Improved harness for breathing apparatus

0001The present invention relates to a harness for breathing apparatus, in particular, a harness for breathing apparatus having a structural support member comprising guide channels for flexible conduits.

0002Self-contained breathing apparatus (SCBA) harnesses comprise a structural support member in the form of a back plate (or back frame), a pair of shoulder straps and a waist belt. The back plate is provided with a valve towards the lower end and a retaining strap. In use, a cylinder of breathable gas is attached to the valve and is secured to the back plate by means of the retaining strap. A number of flexible hoses extend from the valve to the shoulder straps so that breathing apparatus worn by the user may be conveniently connected thereto.

0003<patcit id="pcit0001" dnum="EP1952719A1"><text>EP1952719A1</text></patcit> discloses a harness comprising a back plate, a sliding plate, a pair of shoulder straps and a belt. The sliding plate is slidably attached to the back plate in such a way that it can move longitudinally with respect to the back plate between the extended position and the un-extended position. A valve is provided at the bottom of the back plate. Two air supply hoses, or conduits, are connected to the valve for supplying breathable gas. The hoses are attached to the sliding plate, one being attached to each side. There is a longitudinally extending guide channel for retaining the hoses on either side of the sliding plate.

0004It is known to provide channels on the back plate for guiding the flexible hoses from the valve to the shoulder strap. The positions of these channels usually determine which of the shoulder straps the hoses are positioned on. However, individual users, or groups of users, have different preferences as to where the hoses are positioned.

0005For example, certain fire-fighting brigades specify that all of the hoses must be worn on the left shoulder strap whilst other brigades specify that the hoses must be worn on the right shoulder strap. Further, an individual may prefer to have one of the hoses on the left shoulder and another on the right.

0006In order to accommodate individual users', or groups of users', preferences, either differently configured back plates must be produced, which is expensive, or the hoses must be routed out of the guide channels, which can result in the hoses presenting a snagging risk.

0007It is therefore desirable to provide a versatile back plate.

0008The invention is defined in the attached independent claim, to which reference should now be made. Further, optional features may be found in the sub-claims appended thereto.

0009According to an aspect of the present invention there is provided a harness for breathing apparatus, comprising: a structural support member having a front for accommodating a gas cylinder and a rear for facing the back of a wearer, and left and right sides; left and right shoulder straps disposed towards the left and right sides of the structural support member respectively, each shoulder strap having a first end attached to an upper portion of the structural support member and a second end attached to a lower portion of the structural support member; a plurality of flexible conduits extending from a lower portion of the structural support member along the structural support member each to a position on either the left or right shoulder strap; left and right guide channels extending longitudinally along the structural support member along left and right sides respectively, for accommodating the flexible conduits; and a cross guide channel, extending transversely across an upper region of the structural support member from one side to the other side for accommodating at least one flexible conduit; wherein the cross guide channel has a first end adjacent to an upper end of the left guide channel and a second end adjacent to an upper end of the right guide channel. Preferably at least one of the left and right guide channels is arranged to accommodate at least two flexible conduits.

0010The guide channels may be located on the rear of the structural support member.

0011In a preferred embodiment, at least one of the flexible conduits extends from the front of the lower portion of the structural support member and passes through an opening in the back plate to the rear of the structural support member before extending along the structural support member in a guide channel.

0012Retaining means may be provided for retaining the or each flexible conduit in the or each guide channel. The retaining means may comprise clamping elements provided in the or each guide channel. Alternatively or additionally, the or each guide channel may be shaped to provide the retaining means.

0013In a preferred embodiment, the upper portion of the structural support member comprises a yoke portion having left and right shoulder strap attachment portions to which the first ends of the left and right shoulder straps are attached respectively, at least one of the shoulder strap attachment strap portions having first and second guide channels arranged to guide the or each flexible conduit to the position on the respective shoulder strap. The left and right shoulder strap attachment portions may each have first and second guide channels.

0014The or each flexible conduit may be arranged to be held between a guide channel of the yoke portion and a shoulder strap.

0015The flexible conduits may include a high-pressure hose and a medium-pressure hose. The flexible conduits may include one or more electrical cables.

0016The invention may comprise any combination of the features and/or limitations referred to herein, except combinations of such features as are mutually exclusive.

0017Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: <ul id="ul0001" list-style="none"><li><figref idref="f0001">Figure 1</figref> schematically shows a front view of a back plate for a harness for breathing apparatus according to an embodiment of the present invention;</li><li><figref idref="f0002">Figure 2</figref> schematically shows a rear view of the back plate of <figref idref="f0001">Figure 1</figref>;</li><li><figref idref="f0003">Figure 3</figref> schematically shows a front view of a harness for breathing apparatus comprising the back plate of <figref idref="f0001">Figures 1</figref> and <figref idref="f0002">2</figref>;</li><li><figref idref="f0004">Figure 4</figref> schematically shows a rear view of the harness of <figref idref="f0003">Figure 3</figref>;</li><li><figref idref="f0005">Figure 5</figref> schematically shows a rear view of the back plate alone with flexible conduits located in guide channels in a first configuration;</li><li><figref idref="f0006">Figure 6</figref> schematically shows a rear view of the back plate alone with flexible conduits located in guide channels in a second configuration;</li><li><figref idref="f0007">Figure 7</figref> schematically shows a rear view of the back plate alone with flexible conduits located in guide channels in a third configuration;</li><li><figref idref="f0008">Figure 8</figref> schematically shows a front view of a harness for breathing apparatus comprising the back plate of <figref idref="f0001">Figures 1</figref> and <figref idref="f0002">2</figref> in an alternative arrangement;</li><li><figref idref="f0009">Figure 9</figref> schematically shows a rear view of the back plate alone with flexible conduits located in guide channels in a first configuration;</li><li><figref idref="f0010">Figure 10</figref> schematically shows a rear view of the back plate alone with flexible conduits located in guide channels in a second configuration; and</li><li><figref idref="f0011">Figure 11</figref> schematically shows a front view of the back plate alone with flexible conduits located in guide channels in a third configuration.</li></ul>

0018<figref idref="f0001"><b>Figure 1</b></figref> shows a structural support member 10 (hereinafter referred to as a back plate) for a harness for breathing apparatus. The back plate 10 has a front face 12 which is arranged to have a cylinder of breathable gas mounted thereto. The back plate has a yoke 14 in an upper region of the back plate 10. The yoke 14 comprises left and right shoulder strap attachment portions 16, 18 that allow the upper ends of left and right shoulder straps to be attached to the back plate 10. Towards a lower end of the back plate 10 there is provided left and right shoulder strap attachment portions 20, 22 that allow the lower ends of left and right shoulder straps to be attached to the back plate 10.

0019The lower portion of the back plate 10 also comprises a reducer-valve mounting portion 24 which allows a gas-cylinder reducer valve to be mounted to the back plate 10. An opening 26 is provided in the back plate through which in use, flexible conduits can pass. First and second side handles, or legs 11, are provided which enable the back plate 10 to be carried by a user.

0020<figref idref="f0002"><b>Figure 2</b></figref> shows the rear side 28 of the back plate 10. The rear side 28 of the back plate 10 comprises left and right guide channels 30, 32 that extend longitudinally along the left and right sides of the back plate 10 respectively, from a lower portion to an upper portion. A cross guide channel 34 is also provided that extends transversely across the back plate 10 from a left side to a right side. The left (or first) end of the cross guide channel 34 is adjacent to the upper end of the left guide channel 30 and the right (or second) end of the cross guide channel 34 is adjacent to the end of the upper right guide channel 32.

0021In this embodiment the left and right guide channels 30, 32 are each arranged to accommodate two flexible conduits. The left and right guide channels 30, 32 may in other embodiments comprise a first left channel and a second left channel, and a first right channel and a second right channel. For flexibility, at least one of the left and right guide channels is arranged to accommodate at least two flexible conduits.

0022The guide channels 30, 32 are shaped with projections within and along their length that are arranged to retain flexible conduits within the channels. However, as will be readily apparent to one skilled in the art, other means for retaining flexible conduits within the channels are possible.

0023The left and right shoulder strap attachment portions 16, 18 of the yoke 14 are also adjacent to the upper ends of the left and right guide channels 30, 32 respectively. The left shoulder strap attachment portion 16 is provided with first and second guide channels 36, 38 and the right shoulder strap attachment portion 18 is also provided with first and second guide channels 40, 42.

0024A recess 44 is provided in a central portion of the rear side 28 of the back plate 10. The recess 44 is arranged to accommodate breathing apparatus accessories such as a battery, a pressure transducer or a radio telemetry device, for example. The recess 44 separates the left and right guide channels 30, 32.

0025A waist belt mounting portion 46 is also provided on the rear side 28 of the back plate 10 which enables a waist belt to be pivotally mounted to the back plate 10.

0026<figref idref="f0003"><b>Figure 3</b></figref> shows a harness 100 comprising the back plate 10 as described above. Left and right shoulder straps 110, 120 are attached to the shoulder strap fixing portions 16, 18, 20, 22 and a waist belt 130 is attached to the waist belt mounting portion 46. A gas-cylinder reducer valve 140 is attached to a lower portion of the back plate 10 using the reducer valve mounting portion 24. In this embodiment two flexible conduits 150, 152 extend from the reducer valve 140 to a position on the left shoulder strap 110. The flexible conduits comprise a high-pressure hose 150 and a medium-pressure hose 152. In use, a cylinder of breathable gas (not shown) is mounted to the front 12 of the back plate 10 and is attached at a first end to the reducer valve 140 and at a second end is retained on the back plate 10 using a cylinder-retaining strap (not shown). Breathable gas is delivered through the high-pressure hose 150 to a pressure gauge 160 and through the medium-pressure hose 152 to a connector 162 which can be attached to a breathing mask (not shown). As shown in <figref idref="f0003">Figure 3</figref>, the flexible conduits 150, 152 pass from the front 12 of the back plate 10 to the rear 28 of the back plate 10 through the opening 26.

0027Referring now to <figref idref="f0004"><b>Figure 4</b></figref><b>,</b> the high-pressure hose 150 and the medium-pressure hose 152 are located in the left guide channel 30 in the rear side 28 of the back plate 10. They both extend longitudinally up the left side of the back plate 10 in the left guide channel 30. As shown in <figref idref="f0005"><b>Figure 5</b></figref><b>,</b> the high-pressure hose 150 exits the left guide channel 30 and passes into the first guide channel 36 of the left shoulder strap attachment portion 16 and the medium-pressure hose 152 exits the left guide channel 30 and passes into the second guide channel 38 of the left shoulder strap attachment portion 16. The hoses 150, 152 are retained in the first and second guide channels 36, 38 by the shoulder strap 110. The hoses 150, 152 then extend down the shoulder strap 110 as shown in <figref idref="f0003">Figure 3</figref> and are held in place by a flap 112.

0028As shown in <figref idref="f0006"><b>Figure 6</b></figref><b>,</b> if the wearer desires, the high-pressure hose 150 and the medium-pressure hose 152 can be taken out of the left guide channel 30 and located in the right guide channel 32. The hoses 150, 152 are then located in the first and second guide channels 40, 42 of the right shoulder strap attachment portion 18. This allows the high-pressure hose 150 and the medium-pressure hose 152 to be located on the right shoulder strap 120.

0029In a further configuration and as shown in <figref idref="f0007"><b>Figure 7</b></figref><b>,</b> the high-pressure hose 150 and the medium-pressure hose 152 are located in the right guide channel 32. The high-pressure hose 150 is then located in the cross guide channel 34 to take it from the right side of the back plate 10 to the left side of the back plate 10. The high-pressure hose 150 is then located in the second guide channel 28 of the left shoulder strap attachment portion 16. The medium-pressure hose is located in the first guide channel 40 of the right shoulder strap attachment portion 18. This allows the high-pressure hose 150 to be located on the left shoulder strap 110 and the medium-pressure hose 152 to be located on the right shoulder strap 120.

0030As will be readily apparent to one skilled in the art, other configurations are possible with the guide channel arrangements provided in the back plate.

0031As shown in <figref idref="f0008"><b>Figure 8</b></figref><b>,</b> in a second configuration three flexible conduits 150, 152, 154 extend from the reducer 140 mounted to the back plate 10. A second medium-pressure hose 154 is provided to allow a second user's breathing mask to be attached in an emergency. The three hoses 150, 152, 154 pass through the opening 26 in the back plate 10 to the rear side 28 of the back plate. A high-pressure hose 150 extends to a position on the right shoulder strap 120, a first medium-pressure hose 152 extends to a position on the right shoulder strap 120 and a second medium-pressure hose 154 extends to a position on the left shoulder strap 110. The hoses 150, 152, 154 are held in place by flaps 112, 122.

0032Referring to <figref idref="f0009"><b>Figure 9</b></figref><b>,</b> the high-pressure hose 150 and the second medium-pressure hose 154 are located in the left guide channel 30 in the rear side 28 of the back plate 10. The first medium-pressure hose 152 is located in the right guide channel 32. The high-pressure hose 150 is then located in the cross guide channel 34 which takes it from the left side of the back plate 10 to the right side of the back plate 10. The high-pressure hose 150 is then located in the second guide channel 42 of the right shoulder strap attachment portion 18. The first and second medium-pressure hoses 152, 154 are located in the first guide channels 40, 36 of the right and left shoulder strap attachment portions 18, 16 respectively.

0033In a further configuration shown in <figref idref="f0010"><b>Figure 10</b></figref><b>,</b> the high-pressure hose 150 and the first medium-pressure hose 152 are located in the right guide channel 32 and the second medium-pressure hose 154 is located in the left guide channel 30. The first medium-pressure hose 152 then extends from the right side of the back plate 10 to the left side of the back plate 10 in the cross guide channel 34. The high-pressure hose 150 is located in the first guide channel 40 of the right shoulder strap attachment portion 18 and the first and second medium-pressure hoses 152, 154 are located in the guide channels 16, 18 of the left shoulder strap attachment portion 16. This allows the high-pressure hose 150 to be located on the right shoulder strap 120 and the first and second medium-pressure hoses 152, 154 to be located on the left shoulder strap 110.

0034As will be readily apparent to one skilled in the art, other configurations of the hoses in the guide channels provided are possible.

0035As shown in <figref idref="f0011"><b>Figure 11</b></figref><b>,</b> in an alternative arrangement the high-pressure hose 150 extends from the reducer 140 and is attached to a pressure transducer (not shown) that converts the pressure delivered by the hose 150 into an electrical signal. The electrical signal is output through an electrical cable 156 which is located in the left guide channel 30. The electrical cable 156 is positioned on the left shoulder strap 110 and is attached to an electronic display device 162.

0036The arrangement of the guide channels allows a user to configure his breathing apparatus to suit his particular needs or preferences. Different users prefer different arrangements and different breathing apparatuses have different numbers of hoses. The back plate 10 according to the present invention allows a wide range of hose configurations.