Backpack for self contained breathing apparatus

CROSS-REFERENCE TO RELATED APPLICATIONS

0001This application claims the priority benefit of U.S. Provisional Patent Application No. 60/925,036, filed Apr. 18, 2007, which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

00021. Field of the Invention

0003The present invention generally relates to a backpack assembly for a self contained breathing apparatus.

00042. Description of the Related Art

0005Self contained breathing apparatuses (“SCBA”) are used by firefighters, for instance, while fighting fires. The SCBA generally include backpack assemblies that support many of the components of the SCBA. Because many of the components are modular in nature, many of the components dangle from the backpack assembly and can form potential snag points during movement within a structure. Firefighters have grown accustomed to this but improvement over the prior constructions is possible.

0006In addition, the backpack assemblies are strapped to the hip/waist region of the firefighters using hip pads. To improve comfort, the pads can be configured to move relative to the balance of the backpack assembly. Such movement, however, can cause some psychological discomfort if the firefighter does not believe that the backpack assembly is tightly secured in position.

SUMMARY OF THE INVENTION

0007Accordingly, an improved backpack assembly features several components that are integrated into a streamlined body such that potential snag points are greatly reduced. The integrated body also results in a sleek design that greatly reduces or eliminates bulky protrusions that restrict movement.

0008In addition, a swiveling and pivoting hip plate is provided to attach the hip pad to the balance of the backpack assembly. The configuration disclosed limits movement in manners that improve the fit while improving the feedback from the backpack assembly to the firefighter.

0009Other improvements also include: an improved tank band assembly that can facilitate rapid exchanges of air cylinders including air cylinders having varied diameters and valve stem configurations; colorized straps to quickly identify twists in the straps when the backpack assembly is being put on; a low air warning (audible and/or visual) on a back surface of the backpack assembly so others following the firefighter will be able to identify a low air supply condition if the firefighter does not identify it himself; handles and carabineer attachment points on the backpack assembly that have a pull strength of 1000 pounds or more; enlarged grabs to help tighten the backpack assembly straps while wearing gloves; and an adjustable hip plate assembly that enables the backpack assembly to be customized for various body sizes and shapes.

0010Some aspects of some embodiments of the present invention involve a backpack assembly for a self contained breathing apparatus. The backpack assembly comprises a back frame that has a forward surface and a rearward surface. The forward surface has a lower portion. A hip plate is positioned along the lower portion of the forward surface. A bushing is positioned between the hip plate and the forward surface of the back frame. A plate covers at least a portion of the bushing. A pin connects the hip plate to the back frame and the pin is positioned between at least a portion of the bushing and at least a portion of the plate. In some embodiments, the bushing comprises fingers that contact the pin. In some embodiments, the pin is adapted for rotational movement in a radial direction of the pin such that the hip plate can swivel relative to the back plate about a first axis while pivoting relative to the pin about a second axis. The first axis preferably is generally normal to said second axis. In some embodiments, the bushing can be mounted to the back frame in multiple locations such that the height of the hip plate relative to the back frame can be adjusted.

0011Some aspects of some embodiments of the present invention relates to a self contained breathing apparatus comprising a backpack assembly. The backpack assembly comprises a back frame. A body is mounted to the back frame. The body has an outer periphery defined by an outer periphery of the back frame. The body houses one or more accessories for the backpack assembly and is disposed on an opposite side of the back frame relative to a body of a user of the self contained breathing apparatus. One of the accessories comprises a low air visual alert. In some embodiments, the accessories further comprise a first stage regulator and a power source. In some embodiments, the accessories further comprise a PASS unit, the PASS unit comprising at least one audible alert device and at least one visual alert device. In some embodiments, the accessories further comprise a low air alert device and a low battery alert device. Preferably, at least one audible alert device is located on a first side of the backpack assembly and at least one audible alert device is located on a second side of the backpack assembly where the first side of the backpack assembly being opposite of the second side of the backpack assembly. More preferably, two audible alert devices are located on the first side of the backpack assembly and two audible alert devices are located on the second side of the backpack assembly. The audible alert on the first side of the backpack assembly can be positioned on an upper half of the backpack assembly. The audible alert on the second side of the backpack assembly also can be positioned on an upper half of the backpack assembly. Preferably, at least one of the audible alert devices comprises a bell, a whistle device or a warble whistle.

0012Some aspects of some embodiments of the present invention involve a backpack assembly for a self contained breathing apparatus. The backpack assembly comprises a back frame that comprises at least one opening formed just inside of a peripheral surface of the back frame. The at least one opening defines a handle that supports about 1000 pounds of load. Preferably, a carabineer attachment point is positioned proximate the handle and the carabineer attachment point is capable of supporting 1000 pounds of load. In some embodiments, the carabineer attachment point is positioned between the at least one opening and the peripheral surface of the back frame.

0013Some aspects of some embodiments of the present invention also involve a backpack assembly for a self contained breathing apparatus where the backpack assembly comprises a back frame. A tank band assembly is secured to the back frame and the tank band assembly comprises a tank band, a first handle and a second handle. The first handle is coupled to an adjustment mechanism that adjusts a circumference of the tank band and the second handle is connected to the tank band such that the tank band can be opened and closed. In some embodiments, the first handle and the second handle are on opposite sides of a tank. In some embodiments, the second handle comprises a spring loaded cam locking mechanism.

0014Some other aspects of the present invention relate to a backpack assembly for a self contained breathing apparatus. The backpack assembly comprises a back frame that comprises a rearward surface and a forward surface. The rearward surface and the forward surface are connected by at least one peripheral surface. At least one handle is defined by an opening that is positioned along the peripheral surface. A waist pad is connected to the back frame with a hip plate and the hip plate is connected to a forward surface of the back frame. A shoulder strap is connected to the back frame and a front PASS device is supported by the shoulder strap. The front PASS device is connected by a conduit to an upper housing. The upper housing is mounted to the rearward surface of the back frame. The upper housing comprises a low air audible alarm, a low air visual alarm, a low battery visual alarm and a transducer for a heads-up display. A middle housing is mounted on the rearward surface of the back frame generally below the upper housing. The middle housing comprises a back PASS device. The back PASS device comprises at least one audible alarm device, at least one visual alarm device and at least one firefighter locating beacon. The front and back PASS devices preferably provide two alarms on the front and two alarms on the back such that the PASS devices are not muffled regardless of the positioning of a downed firefighter. A tank band assembly is mounted on the rearward surface of the back frame. The tank band assembly is positioned generally below the middle housing and a tank being mounted within the tank band assembly. A lower housing is mounted on the rearward surface of the back frame. The tank is supported by the lower housing. The lower housing comprises a central power supply and a first stage regulator. A CGA wheel is connected an offset swivel assembly, the offset swivel assembly is connected to a hose and the hose is connected the first stage regulator.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of certain embodiments of the present invention will become apparent from consideration of the description below, which makes reference to the appended drawings.

<figref idref="DRAWINGS">FIG. 1</figref> is a front perspective view of a backpack assembly that is arranged and configured in accordance with certain features, aspects and advantages of the present invention.

<figref idref="DRAWINGS">FIG. 2</figref> is a rear perspective view of the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIG. 3</figref> is a front elevation view of a back frame assembly for the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIG. 4</figref> is a perspective view of a portion of the back frame assembly of <figref idref="DRAWINGS">FIG. 3</figref>.

<figref idref="DRAWINGS">FIG. 5</figref> is an enlarged perspective view of a portion of the back frame assembly of <figref idref="DRAWINGS">FIG. 3</figref>.

<figref idref="DRAWINGS">FIG. 6</figref> is sectioned perspective view of a bushing used in the back frame assembly of <figref idref="DRAWINGS">FIG. 3</figref>.

<figref idref="DRAWINGS">FIG. 7</figref> is a perspective view of the bushing and a pin used in the back frame assembly of <figref idref="DRAWINGS">FIG. 3</figref>.

<figref idref="DRAWINGS">FIG. 8</figref> is a perspective view of a portion of the back frame assembly of <figref idref="DRAWINGS">FIG. 3</figref>.

<figref idref="DRAWINGS">FIG. 9</figref> is an exploded perspective view of the back frame assembly of <figref idref="DRAWINGS">FIG. 3</figref>.

<figref idref="DRAWINGS">FIG. 10</figref> is an enlarged perspective view of a portion of the back frame assembly of <figref idref="DRAWINGS">FIG. 3</figref> in which an ordinate system is introduced.

<figref idref="DRAWINGS">FIGS. 11 and 12</figref> show a hip plate of the back frame assembly of <figref idref="DRAWINGS">FIG. 3</figref> in two different modes of movement.

<figref idref="DRAWINGS">FIG. 13</figref> is a view of the hip plate being connected to a hip/waist pad assembly.

<figref idref="DRAWINGS">FIG. 14</figref> is a top down perspective view of the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIGS. 15 and 16</figref> are perspective views of a heads up display transducer housing that is used in the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIG. 17</figref> is a perspective view of a lower portion of the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIGS. 18 and 19</figref> are perspective views of a hose and swivel attachment to a CGA wheel used in the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIGS. 20 and 21</figref> are views of grabs used in the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIG. 22</figref> is a perspective view of a portion of a unified electrical and pneumatic coupler used in the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIGS. 23 and 24</figref> are perspective views of a front PASS unit used in the backpack assembly of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIGS. 25-31</figref> are views of a tank band assembly used in the backpack of <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIG. 32</figref> is a perspective view of a housing containing a back PASS device and ultrasonic beacons used in the backpack of <figref idref="DRAWINGS">FIG. 1</figref>.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

0037With reference initially to <figref idref="DRAWINGS">FIG. 1</figref> and <figref idref="DRAWINGS">FIG. 2</figref>, a backpack assembly <b>30</b> is illustrated therein. The backpack assembly <b>30</b> has particular utility with self contained breathing apparatuses but certain features, aspects and advantages of the backpack assembly <b>30</b> can be used in other applications. The backpack assembly <b>30</b> is shown with an air cylinder or tank <b>32</b> supported thereon. While not shown, the backpack assembly <b>30</b> can be used with a face piece that, in some embodiments, is provided with a heads up display (“HUD”) and a communication system. Any other suitable accessories also can be used.

0038The illustrated backpack assembly <b>30</b> advantageously features several components that have been integrated together to result in a greatly streamlined backpack assembly <b>30</b> when compared to prior backpack assemblies that had many components attached along peripheral portions of the backpack assemblies. The components are connected to or disposed in a body formed by several housing assemblies. The streamlined backpack assembly results in reduced snag points. The integrated construction also has been configured to achieve a desirable aesthetic appearance for the backpack assembly <b>30</b> and for many of the components of the assembly <b>30</b>.

0039Prior to describing the components of the illustrated backpack assembly <b>30</b> in detail, the overall construction will be introduced. With reference to <figref idref="DRAWINGS">FIG. 1</figref>, the backpack assembly <b>30</b> comprises a back frame <b>34</b>. The back frame <b>34</b> defines a chassis to which the remaining components are assembled. In the illustrated configuration, upper padding <b>36</b> is secured to an upper forward portion of the back frame <b>34</b>. A waist pad <b>40</b> is connected to the back frame <b>34</b> with a swivel and pivot hip plate <b>42</b> (see <figref idref="DRAWINGS">FIG. 3</figref>). The waist pad <b>40</b> is positioned generally below the upper padding <b>36</b> and also is positioned on a forward surface of the back frame <b>34</b>. The swivel and pivot hip plate connection provides comfort and ergonomic weight placement in any body position. The connection leads to 35% greater mobility when side bending, up to 30% greater trunk mobility when forward bending and 20% more hip flexion.

0040A harness <b>44</b> also connects to the back frame <b>34</b>. The harness <b>44</b> preferably comprises two shoulder straps <b>46</b>. Ends of the illustrated shoulder straps <b>46</b> are connected to back straps <b>50</b> preferably using parachute-style buckles <b>52</b>. The buckles <b>52</b> allow easy release but other types of connections can be used. Lower ends of the back straps <b>50</b> can be connected to the hip plate <b>42</b>. The harness <b>44</b> also comprises a waist belt <b>54</b>, which can comprise two portions that are connected by a buckle <b>56</b>. The two portions of the waist belt <b>54</b> preferably are connected to the waist pad <b>40</b> in a manner that will be described below. The shoulder straps <b>46</b> and the waist belt <b>54</b> can be adjusted using portions that are connected to large hand grabs <b>60</b>. Preferably, the straps <b>46</b>, <b>50</b>, the belts <b>54</b>, and the pads <b>36</b>, <b>40</b> are easily replaced in the field.

0041With continued reference to <figref idref="DRAWINGS">FIG. 1</figref>, a front PASS device <b>62</b> is supported by the right (as viewed by the user) shoulder strap <b>46</b>. The PASS device <b>62</b> is a personal alert safety system, which is a one-way communications device used by firefighters entering a building to alert others that the wearer of the PASS device <b>62</b> is in trouble and in need of rescue. The illustrated PASS device <b>62</b> also includes a beacon <b>64</b> for a firefighter locating system. The beacon <b>64</b> can comprise an omnidirectional ultrasonic transmitter, as will be described in greater detail below.

0042A pneumatic hose <b>70</b> and an electrical cable <b>72</b> connect the PASS device to an upper housing <b>74</b>, which is connected to the upper portion of the back surface of the back frame <b>34</b>. With reference now to <figref idref="DRAWINGS">FIG. 2</figref>, a second pneumatic hose <b>76</b> also is connected to the upper housing <b>74</b>. With reference again to <figref idref="DRAWINGS">FIG. 1</figref>, the second pneumatic hose <b>76</b> extends along a portion of the left shoulder strap <b>46</b>. A second electrical cable <b>80</b> also extends along a portion of the left shoulder strap <b>46</b>. The second pneumatic hose <b>76</b> and the second electrical cable <b>80</b> are connected to a third pneumatic hose <b>82</b> and a third electrical cable <b>84</b>, respectively. In the illustrated configuration, a single coupler <b>86</b> is used to connect the pneumatic hoses <b>76</b>, <b>82</b> and the electrical cables <b>80</b>, <b>84</b>.

0043The third pneumatic hose <b>82</b> extends to a second stage regulator (not shown), which can be positioned along the lower left side of the back frame <b>34</b>. The second stage regulator (not shown) can be connected to a face mask or the like.

0044With reference again to <figref idref="DRAWINGS">FIG. 2</figref>, the upper housing <b>74</b> in the illustrated configuration contains a low air audible alarm <b>92</b>, which is positioned to the left side of the upper housing <b>74</b>. The right side of the upper housing <b>74</b> comprises a low air light <b>94</b>, a low battery light <b>96</b> and a HUD transducer <b>100</b>. The upper housing <b>74</b> and the components housed therein will be described in greater detail below.

0045A middle housing <b>102</b> is mounted to the back frame <b>34</b> just below the upper housing <b>74</b>. The middle housing <b>102</b> contains one or more back PASS devices <b>104</b>. Accordingly, the middle housing <b>102</b> includes two audible alert devices <b>106</b> and two visual alert devices <b>110</b>. The illustrated middle housing <b>102</b> also houses two beacons <b>112</b> for the firefighter locating system.

0046A tank band assembly <b>114</b> is mounted to the back frame <b>34</b> just below the middle housing <b>102</b>. The tank band assembly <b>114</b> is used to secure the cylinder <b>32</b> to the back frame <b>34</b>. Advantageously, the tank or cylinder <b>32</b> is secured in a lower position (e.g., the top end of the tank is below the top end of the back frame). The lower position of the tank helps the tank to rotate away from the leg and hip region of the user, which provides space for less restricted mobility. In addition, the lower position allows that tank to slide over the buttocks during trunk extension. The tank band assembly will be described in greater detail below.

0047A lower housing <b>116</b> is mounted to the back frame <b>34</b> just below the tank band assembly <b>114</b>. The lower housing <b>116</b> preferably contains a central power supply <b>118</b>, which can comprise 4 C-cell batteries in series. The central power supply <b>118</b> supplies power to the backpack assembly <b>30</b>. The lower housing <b>116</b> also houses a first stage regulator <b>120</b>. The first stage regulator <b>120</b> can be connected to a removable buddy breather (not shown) by a hose (not shown). A removably coupling can be provided at the end of the hose (not shown) that connects to the lower house <b>116</b> such that the buddy breather (not shown) can be removed if desired. In some configurations, the hose (not shown) can be about 36 inches long. Other lengths can be used. The hose (not shown) can be connected to the first stage regulator <b>120</b> with a swivel coupling (not shown) that swivels about an axis of the hose (not shown) such that the likelihood of kinking of the hose (not shown) is greatly reduced. The buddy breather (not shown) can be positioned within a pouch (not shown) that can be connected to a left side of the back frame <b>34</b>.

0048A CGA wheel <b>132</b> can be connected to the first stage regulator <b>120</b> with a hose <b>134</b>. The hose preferably is connected to the CGA wheel <b>132</b> with an offset swivel assembly <b>136</b>, which provides flexibility in locating the CGA wheel <b>132</b> such that various valve stem configurations can be accommodated by the backpack assembly <b>30</b>.

0049Having introduced a basic construction of the illustrated backpack assembly <b>30</b>, several of the components will be discussed in greater detail with reference to the drawings of one example of the backpack assembly <b>30</b>.

Back Frame

0050As discussed above, the back frame <b>34</b> preferably defines the chassis around which the harness <b>44</b> and the balance of the backpack assembly <b>30</b> are constructed. With reference now to <figref idref="DRAWINGS">FIG. 3</figref>, the back frame <b>34</b> and the articulating hip plate <b>42</b> are illustrated.

0051The illustrated back frame <b>34</b> can be formed in any suitable manner. The illustrated back frame comprises a plate member <b>140</b>. The plate member <b>140</b> of the back frame <b>34</b> can be formed of any suitable material. In one configuration, the plate member <b>140</b> is formed of aluminum. The aluminum back frame <b>34</b> provides a lightweight construction with high strength and rigidity. In some embodiments, the back frame <b>34</b> can be constructed of suitable tubular components. In either configuration, the back frame <b>34</b> defines a suitable platform upon which the balance of the backpack assembly <b>30</b> can be mounted or to which the balance of the backpack assembly <b>30</b> can be attached.

0052With reference to <figref idref="DRAWINGS">FIG. 3</figref> and <figref idref="DRAWINGS">FIG. 4</figref>, the plate member <b>140</b> of the back frame <b>34</b> comprises one or more handle openings <b>142</b>. The handle openings <b>142</b> help to define handles <b>144</b> along the periphery of the plate member <b>140</b>. In the illustrated configuration, the plate member <b>140</b> comprises three openings <b>142</b> and three handles <b>144</b>. The openings <b>142</b> and handles <b>144</b> in the illustrated configuration are positioned at a top of the plate member <b>140</b> and at each lateral side of the plate member <b>140</b>. The openings <b>142</b> and the handles <b>144</b> preferably are sized and configured to allow the backpack assembly <b>30</b> to be lifted or pulled as desired. In one preferred configuration, the handles <b>144</b> are sized and configured to withstand a 1000 pound load (i.e., a 1000 pound drag load). The handles, as shown in <figref idref="DRAWINGS">FIGS. 1 and 2</figref>, preferably also comprise a reinforcing plate <b>146</b> that can be secured to the plate member <b>140</b> using fasteners or any other suitable technique.

0053Moreover, in the illustrated configuration, the handles <b>144</b> include carabineer attachment points <b>148</b>. Preferably, each of the handles <b>144</b> includes one or more attachment point <b>148</b>. In some configurations, however, less than all of the handles <b>144</b> may include an attachment point <b>148</b>. The attachment points <b>148</b> can be formed in any suitable manner. In the illustrated configuration, each of the attachment points <b>148</b> is defined by a hole that extends through the handle <b>144</b> and preferably through the associated reinforcing plate <b>146</b>.

0054With continued reference to <figref idref="DRAWINGS">FIG. 3</figref> and <figref idref="DRAWINGS">FIG. 4</figref>, the plate member <b>140</b> preferably comprises one or more channel <b>150</b>. In the illustrated configuration, two channels <b>150</b> extend along a substantial portion of the length of the plate member <b>140</b>. The channels <b>150</b> protrude from the front surface of the plate member <b>140</b>. A lower portion of each of the illustrated channels <b>150</b> forms a crossing pattern. In some configurations, a separate channel can be used to connect the two channels <b>150</b> that extend in a generally vertical direction. The channels <b>150</b> reinforce the plate member <b>140</b> and can be used as a conduit of internal wires, cables, hoses or the like.

Hip Plate

0055With reference now to <figref idref="DRAWINGS">FIGS. 4 through 12</figref>, the hip plate <b>42</b> (see <figref idref="DRAWINGS">FIG. 3</figref>) has been removed from the back frame <b>34</b> so that a hip plate mounting assembly <b>152</b> can be better shown. The mounting assembly <b>152</b> advantageously enables the hip plate <b>42</b> to articulate relative to the back frame <b>34</b>. The articulation allows motion between the back frame <b>34</b>, which is secured to the shoulders when worn, and the hip plate <b>42</b>, which is secured to the hips and shoulders when worn. In one configuration, the mounting assembly <b>152</b> provides some level of movement between back frame <b>34</b> and the hip plate <b>42</b> while limiting that movement to provide a suitably stiff configuration. Preferably, the hip plate <b>42</b> is not capable of substantial lateral movement relative to the back frame <b>34</b>. More preferably, such lateral motion is significantly restricted with a goal of eliminating lateral motion of a mass associated with the cylinder <b>32</b> that is attached to the back frame <b>34</b>.

0056The illustrated mounting assembly <b>152</b> comprises a bushing <b>154</b>. The bushing <b>154</b> can be formed of any suitable material. In one preferred configuration, the bushing <b>154</b> defines means for dampening and limiting rotation within a desired range. Preferably, the bushing <b>154</b> is formed of an elastomeric material. More preferably, the bushing <b>154</b> is formed of an elastomeric material that can sustain a 500 degrees Fahrenheit flash temperature, a 200 degrees Fahrenheit soak temperature and a temperature of 500 degrees Fahrenheit for 5 minutes. Even more preferably, the bushing <b>154</b> is formed of butyl rubber.

0057The illustrated bushing <b>154</b> preferably comprises a generally cylindrical outer surface <b>156</b> (see <figref idref="DRAWINGS">FIG. 5</figref>). The illustrated bushing <b>154</b> also preferably comprises a pair of inner contoured surfaces <b>158</b>, one of which is shown in the cross-section of <figref idref="DRAWINGS">FIG. 6</figref>. Each of the contoured surfaces <b>158</b> in the illustrated configuration defines two fingers <b>160</b>, which will be discussed in greater detail below. The contoured surfaces <b>158</b> also advantageously define a lower stepped region <b>162</b>. A ridge <b>164</b> also can be defined along a portion of each of the stepped regions <b>162</b>. The fingers <b>160</b> preferably extend over a portion of the thickness of the bushing <b>154</b> while the stepped regions <b>162</b> extend over a balance of the thickness of the bushing <b>154</b>. In other words, in the illustrated embodiment, the stepped regions <b>162</b> and the fingers <b>160</b> together extend over substantially the entire thickness of the bushing <b>154</b>.

0058The bushing <b>154</b> also preferably comprises a pair of mounting holes <b>166</b>. The mounting holes <b>166</b> in the illustrated configuration extend through the entire thickness of the bushing <b>154</b>. Other configurations are possible.

0059With reference to <figref idref="DRAWINGS">FIG. 5</figref>, a pin <b>168</b> preferably extends through a recess defined by the stepped regions <b>162</b>. The pin <b>168</b> comprises a centerline CL. The centerline CL preferably is able to sweep through an included angle α of about 30 degrees in each direction relative to a centered position. In other words, a total sweep of about 60 degrees is possible by the pin <b>168</b>.

0060As shown, the fingers <b>160</b> extend toward the pin <b>168</b>. The pin <b>168</b> preferably is contacted by the fingers <b>160</b> in four places. Other configurations are possible. The illustrated configuration, however, provides an unbiased yet stable hold on the pin <b>168</b> by the bushing <b>154</b>. Advantageously, the fingers <b>160</b> are able to flex (see <figref idref="DRAWINGS">FIG. 7</figref>) when the pin <b>168</b> sweeps through all or at least a portion of the full sweep. By flexing, the fingers <b>160</b> dampen the movement of the pin <b>168</b>, and thereby dampen the movement of the hip plate <b>42</b> relative to the back frame <b>34</b>. The flex of the fingers <b>160</b> also helps to return the pin <b>168</b> to a neutral position, which is generally horizontal in the illustrated configuration.

0061The full sweep angle preferably is defined, at least in part, by an outer portion of the contoured surfaces <b>158</b>. In other words, portions of the contoured surfaces <b>158</b> define stops <b>170</b>. The stops <b>144</b> preferably come into contact with the pin <b>168</b> at the limit of the sweep. Other configurations to limit the sweep of the pin <b>168</b> also are possible.

0062With reference now to <figref idref="DRAWINGS">FIGS. 4 and 5</figref>, the bushing <b>154</b> preferably is sandwiched between the plate member <b>140</b> and a bushing plate <b>172</b>. The bushing plate <b>172</b> preferably is formed of a suitably rigid material. In one embodiment, the bushing plate <b>172</b> is formed of aluminum. Other materials also can be used. The bushing plate <b>172</b> preferably has a diameter that is slightly less than a diameter of the bushing <b>154</b>.

0063The bushing plate <b>172</b> can be secured to the plate member <b>140</b> by suitable fasteners. In one configuration, two standoffs <b>174</b> are secured to the plate member <b>140</b>. The standoffs <b>174</b> can be formed of any suitable material. In the illustrated configuration, the standoffs <b>174</b> are formed of stainless steel. The standoffs <b>174</b> extend at least partially through the mounting holes <b>140</b> of the bushing <b>154</b>. In one embodiment, the standoffs <b>174</b> extend fully through the bushing <b>154</b>. The bushing plate <b>172</b> can be secured to the standoffs <b>174</b> by screws <b>176</b> or other suitable fasteners. Preferably, the bushing plate <b>172</b> moderately squeezes the bushing <b>154</b> when mounted to the plate member <b>140</b>.

0064In the illustrated embodiment, one or more bosses <b>175</b> extend from the surface of the bushing <b>154</b>. The bosses <b>175</b> can be integrally formed with the bushing <b>154</b>. The bosses <b>175</b> are used in conjunction with corresponding slots or recesses <b>177</b> formed in the bushing plate <b>172</b> as alignment aids during manufacturing. Other techniques also can be used.

0065The pin <b>168</b> also preferably is compressed between the bushing <b>154</b> and the bushing plate <b>172</b>. The compression of the pin <b>168</b> advantageously provides a small degree of resistance in the mounting assembly <b>152</b> such that the mounting assembly <b>152</b> is less likely to rattle significantly.

0066With reference to <figref idref="DRAWINGS">FIG. 8</figref>, the hip plate <b>42</b> comprises two mounting ears <b>178</b>. The mounting ears <b>178</b> can be integrally formed with the hip plate <b>42</b> or can be separately formed from the hip plate <b>42</b> and secured to the hip plate <b>42</b> in any suitable manner. The pin <b>168</b> extends through the ears <b>178</b> such that the pin <b>168</b> pivotally secures the ears <b>178</b>, and therefore, the hip plate <b>42</b>, to the mounting assembly <b>152</b>. In one embodiment, the pin <b>168</b> is a rivet. Other types of pins also can be used.

0067The ears <b>178</b> extend alongside a portion of the bushing <b>154</b>. Preferably, the ears <b>178</b> do not extend so far alongside the bushing <b>154</b> that they come into contact with the plate member <b>140</b>. Because the bushing plate <b>172</b> is slightly undersized relative to the bushing <b>154</b>, slight movement of the hip plate <b>42</b> in a manner that causes either the left ear or the right ear of the ears <b>178</b> to move toward the plate member <b>140</b> relative to the other of the ears <b>178</b> will cause one or both of the ears <b>178</b> to rub against the bushing <b>154</b> rather than the bushing plate <b>172</b>, which reduces premature wear of the metal members (i.e., the bushing plate <b>172</b> and the ears <b>178</b>) and reduces rattling.

0068With reference again to <figref idref="DRAWINGS">FIG. 3</figref>, the hip plate <b>42</b> comprises an enlarged central opening <b>180</b>. The enlarged central opening <b>180</b> in the illustrated configuration comprises two opposing rolled edges <b>182</b>, which reinforce the hip plate <b>42</b>. The mounting ears <b>178</b> can be integrally formed with the rolled edges <b>182</b> in some configurations. The enlarged central opening <b>180</b> also comprises a header <b>184</b>, which extends across the top of the opening <b>180</b>. Preferably, the enlarged central opening <b>180</b> generally surrounds the mounting assembly <b>152</b>.

0069With reference to <figref idref="DRAWINGS">FIG. 10</figref>, the bushing <b>154</b>, through resistance to compression loads, allows very limited rotation of the hip plate <b>42</b> about a Y-axis. This rotation about the Y axis also is greatly limited by the ears <b>178</b> that contact the sides of the bushing <b>154</b>. By reducing and/or eliminating the movement about the Y axis, a sensation of stability is provided to the user.

0070The hip plate <b>42</b> can move relative to the plate member <b>140</b> about the X-axis (see <figref idref="DRAWINGS">FIG. 11</figref>). The movement of the hip plate <b>42</b> about the X axis generally is limited by the header <b>184</b> of the hip plate <b>42</b>. The header <b>184</b>, or another upper portion of the hip plate <b>42</b>, can contact either the bushing <b>154</b> or the plate member <b>140</b> in the illustrated configuration. Thus, the hip plate <b>42</b> can move relative to the plate member <b>140</b> in a limited range about the X axis.

0071The hip plate <b>42</b> is able to rotate about the Z-axis in the manners described above (see <figref idref="DRAWINGS">FIG. 12</figref>). The movement of the hip plate <b>42</b> is limited by the interplay between the pin <b>168</b>, the fingers <b>160</b> and the stops <b>170</b>. As described above, the fingers <b>160</b> are designed to easily collapse when the pin <b>168</b> rotates off center about the Z axis. When the fingers <b>160</b> collapse, the fingers <b>160</b> allow a natural and minimally restrictive movement of the pin <b>168</b>. When not being worn, the fingers <b>160</b> generally return the hip plate <b>42</b> to a neutral position, which assists the user when putting on the backpack assembly <b>30</b>. In addition, as discussed above, the stops <b>170</b> limit the range of rotation about the Z axis.

0072With reference again to <figref idref="DRAWINGS">FIG. 3</figref>, the plate member <b>140</b> preferably comprises a plurality of mount holes <b>186</b>. The plurality of mount holes <b>186</b> allows the position of the mounting assembly <b>152</b> to be moved upward or downward along the plate member <b>140</b>. In the illustrated configuration, the middle two of six mount holes <b>186</b> have been used to mount the mounting assembly <b>152</b>. Providing the plurality of mount holes <b>186</b> allows a single plate member <b>140</b> to be used while allowing some customization of sizing to accommodate various body structures of the end users. For instance, at least three different hip plate mounting locations are provided in the illustrated configuration. Thus, some configurations provide customization among a small, a standard and a large configuration to accommodate varied body sizes for the end users.

0073With continued reference to <figref idref="DRAWINGS">FIG. 3</figref>, the illustrated hip plate <b>42</b> comprises an inverted generally T-shaped configuration. The mounting assembly <b>152</b> advantageously is located proximate an upper portion <b>188</b> of the hip plate <b>42</b>, while the base <b>190</b> of the hip plate <b>42</b>, which is adapted to rest in the hip region of an ultimate user, is positioned lower than the mounting assembly <b>152</b>. In some configurations, a hip plate <b>42</b> with an elongated upper portion <b>188</b> can be used in addition to, or as an alternative to, the plurality of mount holes <b>186</b>. In other words, an elongated upper portion <b>188</b> can be used to accommodate a user with a longer torso.

0074With reference to <figref idref="DRAWINGS">FIG. 13</figref>, the pivot point (i.e., the pin <b>168</b>) preferably is spaced apart from a center WB of the waist belt <b>54</b> by a suitable distance DY. Locating the pin <b>168</b> above the center WB of the waist belt <b>54</b> creates a small concave pocket in the user's back when the user bends over, which provides increased comfort for the user. The pocket also reduces the amount of shoulder strap restriction experienced by the user. Moreover, by lengthening the distance DY between the waist belt center WB and the pivot point <b>168</b>, the top of the air cylinder <b>32</b> can lie generally flat against the top of the back, which provides the lowest possible profile when a user is crawling.

Harness

0075With continued reference to <figref idref="DRAWINGS">FIG. 13</figref>, the base <b>190</b> of the hip plate <b>42</b> preferably comprises a plurality of belt apertures <b>192</b>. The belt apertures <b>192</b> are sized and configured to accept suitable webbing or the like. In the illustrated configuration, the hip plate <b>42</b> also comprises two enlarged windows <b>194</b>. The windows <b>194</b> provide access to loops <b>196</b> formed on the waist pad <b>40</b>, as will be explained below. As will be appreciated, a coupler belt <b>198</b> extends through the lower belt apertures <b>192</b> and through the loops <b>196</b>, which will be positioned in the region of the windows <b>194</b>. The coupler belt <b>198</b> can be joined to the waist belt <b>54</b> with D rings or the like.

0076The waist pad <b>40</b> also comprises an upper loop <b>200</b>. The upper portion <b>188</b> of the hip plate <b>42</b> is inserted into the upper loop <b>200</b>. With the upper portion <b>188</b> inserted in the upper loop <b>200</b>, the coupler belt <b>198</b> is passed through the outer belt aperture <b>192</b> at one side of the hip plate <b>42</b>. The coupler belt <b>198</b> then is passed through the first waist strap loop <b>196</b>, which generally is positioned in the region of the window <b>194</b>. The coupler belt <b>198</b> then is passed through the central belt apertures <b>192</b> prior to being passed through the second loop <b>196</b>, which also generally is positioned in the region of the other window <b>194</b>. Finally, the coupler belt <b>198</b> is passed through the other outer belt aperture <b>192</b>. In this manner, the waist pad <b>40</b> can be mounted to the hip plate <b>42</b>.

0077The coupler belt also passes through outer loops <b>202</b> prior to being passed through the D-ring or other suitable coupler plate <b>204</b> (see <figref idref="DRAWINGS">FIG. 1</figref>) and being doubled back on itself. Each lateral end of the coupler belt <b>198</b> can extend through the coupler plate <b>204</b>. The coupler plates <b>204</b> can be used to connect the waist belt <b>54</b> to the coupler belt <b>198</b>. In one preferred configuration, each end of the coupler belt <b>198</b> folds back upon itself and is secured thereto with a belt button <b>206</b>. The belt button <b>206</b> preferably comprises two portions that can be threaded together such that the coupler belt <b>198</b> is removably secured in position. Such a configuration enhances the ability to service the backpack assembly <b>30</b> in the field. For example, the waist pad <b>40</b> can be readily removed and replaced with a coin or screwdriver.

0078The hip plate <b>42</b> also preferably comprises back strap apertures <b>208</b>. The back straps <b>50</b> can be secured to the hip plate <b>42</b> through the back strap apertures <b>208</b> in any suitable manner.

0079Preferably, at least the webbing used for the back straps <b>50</b> and the webbing used for the waist belt <b>54</b> is color coated on one side. In other words, the two sides of the strap have different appearances from each other. The color coating enables twists in the belts and straps to be quickly identified. The color coating can be provided by using a spray on coating or the like. Preferably, the coating is fire retardant. More preferably, the coating stiffens the webbing. In some configurations, the color coating can be woven or silk screened. Other manners of providing webbing that has a color marking on only one side or different color marking on opposing sides also can be used.

Hand Grabs

0080At the end of the back straps <b>50</b> and at the ends of the waist belt <b>54</b> are the oversized hand grabs <b>60</b>. The hand grabs <b>60</b> provide a tactile confirmation as well as a visual confirmation that the backpack assembly <b>30</b> has been properly put on. Moreover, the oversized hand grabs <b>60</b> improve the grip of a gloved hand while putting on the backpack assembly <b>30</b>.

0081With reference now to <figref idref="DRAWINGS">FIG. 20</figref> and <figref idref="DRAWINGS">FIG. 21</figref>, the hand grabs <b>60</b> preferably comprise a two-piece construction. The illustrated hand grabs <b>60</b> comprise a sleeve <b>240</b> and an insert <b>242</b>. The sleeve <b>240</b> preferably comprises a passage through which an end of a belt or strap can be threaded. The insert <b>242</b> preferably comprises a pseudo-D-ring construction with a passageway <b>244</b> defined through a tab <b>246</b>. The tab <b>246</b> preferably comprises studs <b>250</b> on each side with serrated teeth <b>252</b> positioned within the passageway <b>244</b>. Other grabbing structures can be used.

0082The end of the belt or strap can be threaded trough the passageway <b>244</b> and folded back over the tab <b>246</b>. With the end of the belt or strap folded over the tab <b>246</b>, the insert <b>242</b> is pulled back into the sleeve <b>240</b> such that the belt or strap is locked in position relative to the insert <b>242</b> and the sleeve <b>240</b>.

0083With continued reference to <figref idref="DRAWINGS">FIG. 20</figref> and <figref idref="DRAWINGS">FIG. 21</figref>, the sleeve <b>240</b> preferably comprises two lateral slots <b>254</b> and the insert <b>242</b> preferably comprises two posts <b>256</b> that, when the insert <b>242</b> is positioned in the sleeve <b>240</b>, extend laterally outward through the slots <b>254</b>. These posts <b>256</b> reinforce the hand grabs <b>60</b> and provide structure that can be used to guide the insert <b>242</b> fully into the sleeve <b>240</b>.

0084In one configuration, the insert <b>242</b> can be snap fit into the sleeve <b>240</b>. In the illustrated construction, a hole <b>260</b> in the sleeve <b>240</b> can align with a hole in the insert <b>242</b> such that a threaded fastener of the like can be passed into the hole in the insert through the hole <b>260</b> and can be used to secure the insert <b>242</b> within the sleeve <b>240</b>. Other configurations also can be used.

0085The hand grabs <b>60</b> can have any suitable external appearance. In one configuration, a plurality of ribs <b>264</b> is provided to enhance the ability of a user to grip the hand grabs <b>60</b> with a gloved hand. Other configurations also can be used.

Upper Housing

0086With reference now to <figref idref="DRAWINGS">FIG. 14</figref>, a rear perspective view of the backpack assembly <b>30</b> is presented with the tank removed for improved clarity. As shown in <figref idref="DRAWINGS">FIG. 14</figref>, the upper housing <b>74</b> is provided proximate a top portion of the plate member <b>140</b>. The upper housing <b>74</b> in the illustrated configuration houses a heads up display transducer <b>100</b>, alert lights <b>94</b>, <b>96</b> and an audible alarm <b>92</b>.

0087With reference to <figref idref="DRAWINGS">FIGS. 14-16</figref>, the HUD transducer <b>100</b> preferably is positioned within a HUD transducer housing <b>210</b>. The HUD transducer housing <b>210</b> preferably comprises a manifold <b>212</b>. The HUD transducer <b>100</b> is in fluid communication with the manifold and is in electrical communication with a printed circuit board (not shown) or the like. The HUD transducer housing <b>210</b> also comprises a low air LED (not shown) and a low air LED cover <b>214</b>. The HUD transducer housing <b>210</b> also comprises a low battery LED (not shown) and a low battery LED cover <b>216</b>. Thus, the HUD transducer housing <b>210</b> contains visual alarms for both a low battery condition and a low air condition. For low air supply conditions (e.g., less than about ¼ tank), the audible alarm <b>92</b> can emit an audible alert. For instance, a bell, a whistle, a warble whistle or the like can be emitted. In addition, the low air LED, which is positioned below the low air LED cover <b>214</b>, preferably flashes at a first rate when a first level of air (e.g., ¼ tank) is detected and preferably flashes faster when a second level of air, which is lower than the first level or air, is detected (e.g., 1/10 tank).

0088The circuitry contained with the upper housing <b>74</b>, and more specifically the HUD transducer housing <b>210</b>, monitors battery power. The battery power is supplied from the central power supply <b>118</b>, through the HUD transducer circuitry and then to the back PASS <b>104</b> and finally to the front PASS <b>62</b>. The circuitry in the HUD transducer housing <b>210</b> also preferably tracks the air supply using the HUD transducer <b>100</b> in combination with the manifold <b>212</b>. When air pressure is sensed, the circuitry turns on the front PASS <b>62</b>, the back PASS <b>104</b> and any display associated with the HUD transducer. In one particular configuration, the circuitry wakes up the HUD and back PASS <b>104</b> and the back PASS <b>104</b> wakes up the front PASS <b>62</b>.

0089The circuitry also preferably calculates and tracks the airtime remaining based upon the air supply remaining in the tank <b>32</b>. This information, together with information from the PASS devices, is logged and the information regarding remaining air time can be presented to the user through a HUD or other display, such as in the mask, for instance. In one configuration, a data log is created for each time the PASS devices <b>62</b>, <b>104</b> are turned on, turned off or enter an alarm mode. In another configuration, the data log records the intervals of air remaining while the air is being used. In one preferred configuration, the data log captures the most recent 2,000 events. Other numbers of events also can be captured and retained for downloading. Further, the data logged can be downloaded to a personal computer or the like for analysis. For this reason, a data port can be provided. The data port can be housed in a water-resistant portion of the backpack assembly <b>30</b>. In the presently preferred configuration, the data port is positioned behind the upper back support padding <b>36</b> in a water tight compartment. Other configurations are possible.

0090The circuitry can be connected to circuitry contained in the middle housing <b>102</b> using a pin sleeved cable <b>216</b>. The cable can be hardwired to the circuitry contained in the HUD transducer housing <b>210</b> and can use spring pins <b>218</b> to connect to the circuitry in the middle housing <b>102</b>. Other configurations also are possible.

0091The upper housing <b>74</b> also comprises the low air audible alarm <b>92</b>. The audible alarm <b>92</b> can comprise speakers, bells or the like. The audible alarm <b>92</b> advantageously is positioned proximate an ear of a user and to a lateral side of any tank that may be carried by the backpack assembly <b>30</b>.

Middle Housing

0092The middle housing <b>102</b> can contain one or more PASS devices <b>104</b>. In the illustrated configuration, the middle housing <b>102</b> contains the left PASS device <b>104</b> and the right PASS device <b>104</b>. As described above, the PASS device <b>104</b> is a personal alert safety system, which is a one-way communications device used by firefighters entering a building to alert others that the wearer of the PASS device is in trouble and in need of rescue. In the illustrated configuration, each PASS device <b>104</b> comprises the transducer or speaker <b>106</b> and the visual alert, such as the LED <b>110</b>. Advantageously, each speaker <b>106</b> is angled outward such that the speaker <b>106</b> is angled away from the air cylinder <b>32</b> that is secured to the back frame <b>34</b> during use. In this manner, the sound emitted from the speaker <b>106</b> is less likely to be obstructed by the tank. The speakers preferably emit a sound pressure level of at least 95 dBA and preferably are tested to temperatures of at least 900° F.

0093The PASS device <b>104</b> can comprise a sensor configuration. For example, the sensor configuration can comprise a three-axis accelerometer or the like. In a preferred configuration, however, the signals regarding movement are provided to the back PASS device <b>104</b> from a sensor associated with the front PASS device <b>62</b>, which experiences significantly more movement than the back PASS device <b>104</b> because the front PASS device <b>62</b> is dangling from the shoulder strap <b>46</b>. Nevertheless, any suitable sensor configuration can be used. When the sensor configuration senses that no movement has occurred for a predetermined period (e.g., approximately 20 seconds), an alarm sequence is activated, which causes a sound to be emitted from the speaker <b>106</b> and causes the LED <b>110</b> to flash. The LED <b>110</b> also can flash to indicate that the PASS device <b>104</b> is operational and/or to indicate whether the PASS device <b>104</b> is in a sensing or alarm mode. The back PASS device <b>104</b> preferably powers the alert devices <b>106</b>, <b>110</b>.

0094Power is supplied to the back PASS devices <b>104</b> from the central power supply <b>118</b>. The power is supplied separately to the HUD transducer <b>100</b> and the back PASS devices <b>104</b>, which therefore can be separately powered. The separate power supplies also enable the back PASS devices <b>104</b> to be powered down without powering down the HUD transducer <b>100</b> and its associated circuitry. In addition, the back PASS devices <b>104</b> can be provided as separate modules and, therefore, the separate supply of power to the two devices enables simplified manufacture regardless of whether the optional back PASS devices <b>104</b> are included or not.

0095The back PASS device <b>104</b> also can provide power to the beacons <b>112</b>. In a preferred configuration, the beacons <b>112</b> are not powered unless the PASS devices <b>104</b> enter an alarm mode. The beacons <b>112</b> can be positioned to the lateral sides of the middle housing <b>102</b>. Preferably, the beacons <b>112</b> are somewhat protected by cages <b>113</b> that are positioned over the beacons <b>112</b>. By positioning the beacons <b>112</b> to each lateral side, the beacons <b>112</b> are much more likely to be detected during a rescue operation.

Lower Housing

0096The lower housing <b>116</b> preferably comprises a central power source housing portion <b>222</b> positioned to one side of the lower housing <b>116</b>. The housing portion <b>222</b> preferably is sized and configured to contain the four C-cell batteries in series described above. Other configurations also are possible. Preferably the power source housing portion <b>222</b> comprises a lower closure <b>224</b> that substantially seals an opening into a power source chamber defined within the central power source housing portion <b>222</b>. The closure <b>224</b> preferably comprises a recessed portion that allows the closure to be removed with the use of a coin or a flathead screwdriver. Thus, the closure <b>224</b> protects the central power source while facilitating a rapid replacement of the central power source while in the field.

0097With reference again to <figref idref="DRAWINGS">FIG. 1</figref>, a bumper <b>226</b> preferably protects a lower portion of the back frame <b>34</b>. In the illustrated configuration, the bumper <b>226</b> covers a lower portion of the back frame <b>34</b>. The bumper <b>226</b> reduces the likelihood that the backpack assembly <b>30</b> will slip on a floor surface when not being worn and also reduces the likelihood that the backpack assembly will scratch a floor surface due to sliding on the floor surface when not being worn.

0098With reference to <figref idref="DRAWINGS">FIG. 17</figref>, a lower portion of the lower housing <b>116</b> preferably comprises at least one tank support <b>228</b> and a central tank recess <b>230</b>. In the illustrated configuration, two tank supports <b>228</b> are positioned to support the tank, which is partially received within the central tank recess <b>230</b>. In particular, the illustrated tank supports <b>228</b> are positioned on each side of the tank <b>32</b> and limit the downward movement of the tank <b>32</b> relative to the tank band assembly <b>114</b>. The tank supports preferably <b>228</b> have a rubberized surface although other constructions are possible.

0099As shown in <figref idref="DRAWINGS">FIG. 2</figref>, a rapid intervention crew/company universal air connection system (RIC UAC) <b>232</b> is positioned at the bottom of the illustrated lower housing <b>116</b> proximate to the CGA wheel <b>132</b>. The RIC/UAC <b>232</b> allows emergency replenishment of breathing air to the tank <b>32</b> in manners known to those of skill in the art.

Offset Swivel Assembly

0100The offset swivel assembly <b>136</b> connects the hose <b>134</b> to the CGA wheel <b>132</b>. With reference to <figref idref="DRAWINGS">FIG. 18</figref> and <figref idref="DRAWINGS">FIG. 19</figref>, the swivel assembly <b>136</b> will be described in greater detail. As illustrated in <figref idref="DRAWINGS">FIG. 19</figref>, the illustrated swivel assembly <b>136</b> facilitates rotation about three axes: A<b>1</b>, A<b>2</b> and B<b>1</b>. The first two axes A<b>1</b>, A<b>2</b> are generally parallel to each other and the third axis B<b>1</b> is generally perpendicular to the first two axes A<b>1</b>, A<b>2</b>. An offset link <b>234</b> connects the wheel <b>132</b> to a fitting <b>236</b> at the end of the hose <b>134</b>. Preferably, a fluid passage is defined through a first pivot shaft that connects the fitting <b>236</b> and the offset link <b>234</b> and a fluid passage is defined through a second pivot shaft that connects the offset link <b>234</b> and the wheel <b>132</b>. The offset link <b>234</b> also comprises a fluid passage. Accordingly, while the offset link <b>234</b> can rotate about the axis A<b>1</b> and the axis A<b>2</b>, a fluid passage extends through the coupling between the hose <b>134</b> and the CGA wheel <b>132</b>.

Quick Disconnect

0101With reference to <figref idref="DRAWINGS">FIG. 1</figref> and <figref idref="DRAWINGS">FIG. 22</figref>, the coupler <b>86</b> provides a simultaneous quick disconnect between two pneumatic hoses and two electrical cables. With reference to <figref idref="DRAWINGS">FIG. 22</figref>, a first portion <b>266</b> and a second portion <b>282</b> of the coupler <b>86</b> are shown. As illustrated, the coupler <b>86</b> features an electrical portion <b>270</b> and an air portion <b>272</b> that are integrated into a single component. The electrical portion of the first portion <b>266</b> can comprise a gasket <b>273</b>. A raised wall <b>268</b> of the second portion <b>282</b> can be positioned within a recess <b>269</b> formed within the first portion <b>266</b>. The raised wall <b>268</b> can be received within the recess <b>269</b>, or other slot or opening, formed within the second portion <b>282</b>, which mates with the first portion <b>266</b>. The mating wall and slot align in only one angular orientation, which results in the pins of the electrical portion being properly aligned with respective sockets during coupling. Accordingly, the coupler <b>86</b> enables a connection between the air portions only when the electrical portions are properly aligned.

0102The coupler operates similar to most quick disconnects. To separate the two portions <b>266</b>, <b>282</b> of the coupler <b>86</b>, a push ring on the second portion <b>282</b> is urged toward the first portion <b>266</b>. When the push ring moves, the two portions can be disconnected.

Front PASS Device

0103The front PASS device <b>62</b> is illustrated in <figref idref="DRAWINGS">FIG. 23</figref> and <figref idref="DRAWINGS">FIG. 24</figref>. In some configurations, the front PASS device <b>62</b> may not be included with the backpack assembly <b>30</b>. When included, however, it preferably is positioned along the right shoulder strap <b>46</b>. The front PASS device <b>62</b> contains various circuitry, sensors and other components.

0104In one configuration, the front PASS device <b>62</b> comprises an outer housing <b>290</b>. The outer housing <b>290</b> preferably is rugged and substantially liquid resistant. A motion detection apparatus can be positioned within the outer housing <b>290</b>. The motion detection apparatus can comprise a three axis accelerometer. Other types of motion detection apparatuses can be used, including but not limited to, mercury switches and laser beams targeting a mirror on a spring.

0105The motion detection apparatus preferably is connected to circuitry that can be used to detect when the front PASS device <b>62</b> has been stationary for a preset period. In one configuration, the preset period is about twenty seconds. If the front PASS has been stationary for the preset period, then an alarm mode is entered. During the alarm mode, the front PASS drives a speaker <b>292</b> that is mounted in the outer housing <b>290</b>. The front PASS <b>62</b> also drives the back PASS <b>104</b>.

0106With reference still to <figref idref="DRAWINGS">FIG. 23</figref>, an LED lens <b>294</b> is mounted in the outer housing <b>290</b> or boot. The LED lens <b>294</b> overlies two or more status lights. The multiple LED lights positioned under the lens <b>294</b> provide improved visibility and provide redundant backup in case of LED failure. The multiple LED lights preferably flash periodically to indicate that the front PASS is operational and the multiple LED lights preferably flash more rapidly or in a different pattern to indicate that the power supply is running low. The multiple LED lights also enable green lights to be used with the front PASS <b>62</b> is in the sensing mode, while red lights are used with the front PASS <b>62</b> is in alarm mode and yellow (amber) lights are used to give a user battery status information, even when the backpack assembly <b>30</b> is not being used.

0107An analog gauge (see <figref idref="DRAWINGS">FIG. 24</figref>) is positioned under a gauge cover <b>300</b>. The analog gauge is a redundant feature that advantageously works independent of the electronic sensing systems using data from the HUD transducer <b>100</b>. The gauge preferably comprises a photoluminescent face <b>302</b>, which improves the visibility of a needle <b>304</b>. If power is needed for the analog gauge, an external power source can be provided.

0108As illustrated, an alarm button <b>306</b> can be provided. The alarm button <b>306</b> can be mounted in any orientation on the front PASS <b>62</b>. Preferably, the alarm button <b>306</b> is large enough for easy manipulation by a gloved hand. The alarm button <b>306</b> allows a user to put the front PASS into alarm mode at any time simply by pressing the button <b>306</b>. Thus, in the event of an emergency experienced by the user, the alarm button <b>306</b> can be depressed such that the front PASS, back PASS and any beacons enter the alarm mode. To reset the alarm, the alarm button <b>306</b> can be depressed two consecutive times.

0109To connect the front PASS <b>62</b> to the back PASS <b>104</b>, a power cable <b>310</b> can be provided. Within the power cable <b>310</b> can be 2 power wires and three signal wires. The signal wires can comprise the following wires: low battery, signal, and ground. The power cable <b>310</b> can be hard wired to the front PASS <b>62</b> and can be connected to the back PASS <b>104</b> with spring pin couplers. In the illustrated configuration, a five spring pin coupler can be used. In some embodiments, more data can be transmitted with a power cable <b>310</b> having additional wires and a corresponding number of spring pins can be found on the associated spring pin coupler.

0110The illustrated front PASS <b>62</b> also has the beacon <b>64</b> built in to the front PASS housing <b>290</b>. Because the beacon <b>64</b> can be an optional element, the beacon <b>64</b> is secured to the housing <b>290</b> with threaded fasteners and is positioned within its own protective housing <b>312</b>. Other configurations are possible.

Tank Band Assembly

0111The tank band assembly <b>114</b> advantageously allows loosening with a single hand and facilitates rapid tank exchanges. As will be described with reference to <figref idref="DRAWINGS">FIG. 25</figref>, the tank band assembly <b>114</b> preferably comprises a locking mechanism <b>320</b> that can be released with a thumb and a cam latch mechanism <b>322</b> can be operated with a hand to loosen a tank band <b>324</b>.

0112In one preferred configuration, the tank band <b>324</b> can be lengthened to expand a diameter of the tank band <b>324</b> or shortened to shrink a diameter of the tank band <b>324</b> by operating the cam latch mechanism <b>322</b>, which is positioned to one side of the cylinder <b>32</b> in the illustrated configuration. Thus, the illustrated tank band assembly <b>114</b> facilitates the rapid exchange of cylinders having different diameters. In a preferred configuration, the tank band assembly <b>114</b> enables the backpack assembly <b>30</b> to accommodate tanks with diameters ranging from at least about 5 inches to at least about 7.3 inches. Once a cylinder is positioned within the tank band assembly <b>114</b>, the slack of the tank band <b>324</b> can be slid into the cam latch mechanism <b>304</b>, which can be snapped to a locked position prior to the tank band locking mechanism <b>320</b> tightening the tank band <b>324</b> around the cylinder <b>32</b>.

0113With reference to <figref idref="DRAWINGS">FIG. 25</figref>, the illustrated tank band assembly <b>114</b> comprises a base <b>330</b>. The base <b>330</b> can be used to secure the tank band assembly to the back frame <b>34</b>. In the illustrated configuration, the base <b>330</b> comprises four mounting holes <b>332</b>. The mounting holes can receive mechanical fasteners, which secure the base <b>330</b> to the back frame <b>34</b>. In some configurations, the base <b>330</b> can be secured in other manners, including but not limited to, interlocking mechanical structures, adhesives and the like.

0114The illustrated base <b>330</b> comprises two pairs of ears <b>334</b>. One set of the ears <b>334</b> pivotally connects the tank band locking mechanism <b>320</b> to the base <b>330</b> and the other set of ears <b>334</b> pivotally connects the cam latch mechanism <b>322</b> to the base <b>330</b>. Other mounting configurations also can be used to secure the tank band locking mechanism <b>320</b> and the cam latch mechanism <b>322</b> to the base <b>330</b>. A central portion of the base <b>330</b> also comprises a recess <b>336</b> that is generally cylindrical in shape. The recess <b>336</b> accommodates a portion of the tank band <b>324</b> that is not being used to secure the cylinder <b>32</b>.

0115The cam latch mechanism <b>322</b> allows excess tank band to be removed from between the cam latch mechanism <b>322</b> and the tank band locking mechanism <b>320</b>. The cam latch mechanism comprises a main pivot arm <b>340</b>. The main pivot arm <b>340</b> preferably is pivotally connected to the base <b>330</b>. In the illustrated configuration, a pivot shaft <b>342</b> connects the main pivot arm <b>340</b> to the respective ears <b>334</b>. The shaft <b>342</b> can be secured in position in any suitable manner, such as through the use of snap rings <b>344</b>, for instance but without limitiaton. In one configuration, the main pivot arm <b>340</b> can include ribs <b>345</b> (see <figref idref="DRAWINGS">FIG. 27</figref>) that abut upon the base <b>330</b> such that the range of pivotal movement of the main pivot arm <b>340</b> relative to the base <b>330</b> can be limited. The limited range advantageously reduces or eliminates the ability of the main pivot arm to flop from side to side when a tank is not mounted to the backpack assembly <b>30</b>.

0116The main pivot arm <b>340</b> preferably defines a slot <b>346</b>. The slot is sized and configured to receive the width and thickness of the tank band <b>324</b>. In the illustrated configuration, the slot <b>346</b> is formed at least in part by an inner surface <b>350</b>. Preferably, the inner surface is generally cylindrical in shape and defines a portion of a cylindrical surface in which the tank <b>32</b> will be positioned.

0117An upper portion of the main pivot arm <b>340</b> defines a through bore that contains a shaft <b>352</b>. The shaft <b>352</b> supports two torsion springs <b>354</b> at each end of the shaft <b>352</b>. The torsion springs preferably are housed within the portion of the main pivot arm <b>340</b> through which the shaft extends. The main pivot arm <b>340</b> also comprises slots <b>356</b> that receive one end of the torsions springs <b>354</b>. The other end of the torsion springs <b>354</b> preferably connect to a locking bracket <b>360</b>. Thus, the locking bracket <b>360</b> can be biased into an open position when no tank <b>32</b> is mounted to the backpack assembly <b>30</b>.

0118The locking bracket <b>360</b> is pivotally connected to the main pivot arm <b>340</b> by the shaft <b>352</b>. In the illustrated configuration, the locking bracket <b>360</b> comprises a tab <b>362</b> that ends in at least one tooth <b>364</b>, but preferably two teeth <b>364</b> are provided. The two teeth <b>364</b> extend into the slot <b>346</b> when the locking bracket <b>360</b> is in a closed position, which is shown in <figref idref="DRAWINGS">FIGS. 26 and 27</figref>. When the teeth are engaged with the tank band <b>324</b>, the ends of the teeth maintain the locking bracket <b>60</b> in the closed position. Preferably, the inner surface <b>350</b> of the main pivot arm <b>340</b> also comprises corresponding apertures <b>366</b>. The apertures, in one configuration, accommodate the teeth <b>364</b> when the locking bracket <b>360</b> is pivoted to the closed position.

0119For aesthetic reasons and for improving the grip one can get on the locking bracket <b>360</b>, a handle <b>370</b> (omitted from <figref idref="DRAWINGS">FIG. 27</figref> to clearly show the locking bracket <b>360</b>) can be secured over the outer portion of the locking bracket <b>360</b>. The handle <b>370</b> can be sized and configured as desired. In the illustrated configuration, the handle <b>370</b> is secured to the locking bracket <b>360</b> with rivets <b>372</b> or other mechanical fasteners. Other suitable fastening techniques also can be used.

0120As explained above, the torsion springs <b>354</b> urge the locking bracket <b>360</b> toward the opened position. Thus, to limit the movement of the locking bracket <b>360</b> and the handle <b>370</b> in the opened direction, a rib <b>374</b> is positioned on the main pivot arm <b>340</b>. When the handle <b>370</b> is moved toward the opened position, an upper surface of the illustrated handle <b>370</b> comes into abutment with the rib <b>374</b> such that the range of handle movement can be limited. Other constructions can be used.

0121With reference now to <figref idref="DRAWINGS">FIG. 28</figref>, the tank band locking mechanism <b>320</b> will be described in further detail. The mechanism <b>320</b> also comprises a main pivot arm <b>380</b>. A pivot shaft <b>382</b> pivotally couples the main pivot arm <b>380</b> to the ears <b>334</b> of the base <b>330</b>. The pivot shaft <b>382</b> can be secured in position in any suitable manner, such as through the use of snap rings <b>384</b> or the like.

0122The main pivot arm <b>380</b> preferably comprises structure that works together with structure on the base <b>330</b> to limit the pivot range of the main pivot arm <b>380</b> relative to the base <b>330</b>. In the illustrated arrangement, the main pivot arm <b>380</b> comprises ribs <b>386</b> (<figref idref="DRAWINGS">FIG. 29</figref>) that abut on the base <b>330</b> to limit the movement of the main pivot arm <b>380</b> toward the other main pivot arm <b>340</b>. Because the tank band <b>324</b> connects the two pivot arms <b>340</b>, <b>380</b> and because the main pivot arms <b>340</b>, <b>380</b> each limit the range of movement in opposing directions, the overall movement of the three components can be limited in each direction when no tank <b>32</b> is enclosed by the assembly <b>114</b>.

0123A support bracket <b>390</b> (see <figref idref="DRAWINGS">FIG. 30</figref>) has a tab that extends downward into a pocket formed in the main pivot arm <b>380</b>. Helical springs <b>392</b> are mounted to shafts <b>394</b> at their upper ends and are mounted to rivets <b>396</b> or other mechanical fasteners or structures formed in the main pivot arm <b>380</b>. The springs <b>392</b> allow some relative movement between the support bracket <b>390</b> and the main pivot arm <b>380</b>.

0124With reference to <figref idref="DRAWINGS">FIG. 31</figref>, a cam bracket <b>400</b> is pivotally coupled to the support bracket <b>390</b> with the shafts <b>394</b>. The cam bracket <b>400</b> therefore can pivot about the shafts <b>394</b> relative to the support bracket <b>390</b>. An end portion <b>402</b> of the tank band <b>324</b> preferably is rolled or otherwise connected to a member forming a passage. The passage receives a shaft <b>404</b> (<figref idref="DRAWINGS">FIG. 30</figref>). The shaft <b>404</b> is supported by the cam bracket <b>400</b>. Advantageously, the shaft <b>404</b> is positioned lower (in the figures) than the shafts <b>394</b>. Thus, when the cam bracket <b>400</b> pivots downward relative to the support bracket <b>390</b>, the end portion <b>402</b> of the tank band <b>324</b> is moved such that the band tightens around the cylinder <b>32</b>. In addition, by virtue of the forces loaded on the locking mechanism <b>320</b> when the cylinder <b>32</b> is captured by the band <b>324</b>, the cam bracket <b>400</b> tends to stay in the closed position without any retaining feature.

0125A handle <b>406</b> (<figref idref="DRAWINGS">FIG. 29</figref>) can be secured to the cam bracket <b>400</b> in any suitable manner. In the illustrated configuration, the handle <b>406</b> is secured with rivets <b>410</b> or other mechanical fasteners. The handle <b>406</b> can comprise a first portion or strike <b>412</b> of a latch lock assembly <b>414</b>. The strike <b>412</b> can be positioned within a generally enclosed passage at one side of the handle <b>406</b>. A finger <b>416</b> preferably is joined to the support bracket <b>390</b> by a mechanical fastener <b>420</b> of the like. The finger <b>416</b> engages the strike <b>412</b> of the latch lock assembly <b>414</b> when the handle <b>406</b> is pivoted to the closed position. In this manner, the latch lock assembly <b>414</b> assists in maintain the tank band locking mechanism <b>320</b> in a closed position. Of course, to unlock or open the tank band locking mechanism <b>320</b>, a user can push the finger <b>416</b> over the strike <b>412</b> and raise the handle <b>406</b> to release the tension on the band <b>324</b>.

0126The tank band <b>324</b> preferably comprises a plurality of apertures <b>420</b>. In the illustrated configuration, the apertures <b>420</b> correspond in size, shape and position to the teeth <b>364</b> of the cam latch mechanism <b>322</b>. Preferably, the teeth are punched from the inside surface of the tank band <b>324</b> to reduce the likelihood of damage to the tank by the minimal burring that could result. A portion of the tank band <b>324</b> also comprises a central slot <b>422</b>. While the illustrated slot <b>422</b> is positioned centrally, other locations also can be used. The slot <b>422</b> preferably also is formed from the inside surface of the tank band <b>324</b>. Moreover, in some configurations, the tank band <b>324</b> features rolled outer surfaces to further protect the tank <b>32</b>.

0127The slot <b>422</b> advantageously does not extend fully to either end of the tank band <b>324</b>. A protrusion formed in the cam latch mechanism rides in the slot <b>422</b>. In one configuration, the protrusion is formed on a back side of the inner surface <b>350</b>. The protrusion and the slot cooperate to limit the amount of outfeed or infeed of the tank band <b>324</b> relative to the cam latch mechanism <b>322</b>.

0128With continued reference to <figref idref="DRAWINGS">FIG. 28</figref>, the base <b>330</b> preferably also comprises sloping bosses <b>424</b> or other such surfaces to reduce the likelihood that the tank band <b>324</b> will feed between the base <b>330</b> and the main pivot arm <b>380</b>. Other suitable configurations also can be used.

0129In accordance with the description above, the distance of the tank to the lumbar spine can be minimized. In addition, the center of the tank can better align with the lower thoracic region, which allows a more upright trunk posture. Moreover, pressures measured at the scapular and sacral regions are negligible (equal or less than about 5 pounds) while traditional SCBAs measure up to 15 pounds of pressure at the scapular region and 22 pounds at the sacral region.

0130Although these inventions have been disclosed in the context of a certain preferred embodiments and examples, it will be understood by those skilled in the art that the present inventions extend beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the inventions and obvious modifications and equivalents thereof. In addition, while a number of variations of the inventions have been shown and described in detail, other modifications, which are within the scope of the inventions, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or subcombinations of the specific features and aspects of the embodiments may be made and still fall within one or more of the inventions. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combine with or substituted for one another in order to form varying modes of the disclosed inventions. Thus, it is intended that the scope of the present inventions herein disclosed should not be limited by the particular disclosed embodiments described above.