Flow signal for compressed gas tanks

Sept. 22, 1964

E. GAGNAN ETAL

3,149,752

FLOW SIGNAL FOR COMPRESSED GAS TANKS

Filed Dec. 21, 1960

<img file="US3149752A_D0001.tif" />

3,149,752

Patented Sept. 22, 1364

United States Patent Office

3,149,752

FLOW SIGNAL FOR COMPRESSED GAS TANKS Emile Gagnan, Montreal, Quebec, Canada, and Jacques

Yves Cousteau, Monaco, Monaco, assignors to La Spirotechnique

Filed Dec. 21, 1960, Ser. No. 77,371

Claims. (Cl. 22'2—3)

The present invention is concerned with improvements in warning devices adapted for use in combination with compressed gas tanks so as to provide an audible warning when there is flow from such tanks.

Such an arrangement is useful in all installations where gas is stored in pressurized containers and indication is desired when the gas is flowing from such containers. For example, in an industrial set up it is common practice to have cylinders of compressed gas stored in one location with feeding conduits leading to a further and remote location where the gas is actually used. With the present invention an audible signal is provided within each container so that as the gas flows from the container an indication is given at the main storage point. This is particularly useful if the gas being used is toxic or inflammable so that if a signal is noted at the storage point when use is not normal it indicates a leak or failure to shut off the pipeline at the point of use.

A preferred use for the present warning device is in combination with compressed gas tanks used by divers or similar breathing apparatus used in toxic or unbreathable atmospheres.

The normal arrangement in a diver’s compressed gas tank is to provide some means of supplying a reserve flow when the pressure has dropped to a level making it imperative for the diver to surface. Normally a full tank has from about 2000 to 2500 p.s.i. and the reserve is used when the pressure drops to from 200 to 500 p.s.i. This of course will vary with the apparatus being used.

At the present time there are many types of reserve air control valves, most of which operate on the principle that the lack of air serves as a warning to the diver when the pressure drops to near the predetermined reserve pressure. The diver then manually operates a reserve valve which permits the full flow use of the remaining gas in his tank or tanks.

The present invention provides a means whereby an audible warning signal is given to the diver when the reserve pressure is reached.

The device of the invention accomplishes these and other purposes by providing a vibrating or knocking device within the interior and contacting the wall of the tank which is actuated by the flow of gas from the container. Means are provided whereby this knocking device may be actuated only when the gas pressure within the tank drops to a predetermined reserve pressure level, or it may be arranged to operate on any and all flow of gas from the container.

.Having thus generally described the nature of the invention, particular reference will be made to the accompanying drawings, and in which:

FIGURE 1 is a side view in vertical cross-section along the line 1—1 of FIGURE 7 of one preferred form of a gas flow operated audible warning device according to the invention.

FIGURE 2 is a transverse cross-sectional view of the construction of FIGURE 1 along the line 2—2.

FIGURE 3 is a transverse cross-sectional view of the construction of FIGURE 1 along the line 3—3.

FIGURE 4 is a side view in vertical cross-section of a further preferred form of a gas flow operated audible warning device according to the invention.

FIGURE 5 is a transverse cross-sectional view of FIGURE 4 along the line 5—5.

FIGURE 6 is a view in side elevation and partially in section of a typical compressed gas tank assembly embodying an audible warning device as shown in FIGURE 4.

FIGURE 7 is a view in side elevation and partially in section of a typical compressed gas tank assembly embodying an audible warning device as shown in FIGURE 1.

FIGURE 8 is a side view in vertical cross-section of a pressure operated flow control valve particularly suited for use in combination with the audible warning devices of the invention when embodied in the gas tanks of a diving apparatus.

With particular reference to FIGURES 1 and 4 of the drawings, two preferred embodiments of the invention are shown in vertical cross-section.

The first assembly indicated at 10 consists of a main body 12 of substantially hexagonal cross-section which is bored axially to provide a tapering recess 14 suitably tapped to receive a threaded coupling 15, as will be described later, and continuing from the recess 14 a concentric flow passage 16 leading into a transverse boring 18. A further restricted flow passage 20 extends from the boring 18 to an enlarged axial recess 22 having a further enlargement 24 leading outwards of the body 12. A further restricted boring 26 extends transversely through the body 12 to provide a flow passage from the boring 18. A pressure valve consisting of a ball 28 and a spring 30 is mounted in the boring 18 by a pressed-in cap 32 having an O-ring seal 34, as shown in detail in FIGURE 2.

The impact or knock creating portion of the assembly 10 consists of a resilient washer 40 having an axial opening 42 and a ball 45 is mounted on the washer 40 and spring loaded by a spring 41 so as to be adapted for seating and unseating on the opening 42. A domed cap 44 having a plurality of gas flow openings 46 is mounted over the washer 40 within the recess enlargement 24 and acts as a support and guide for a headed impact member 48. The stem 49 of the member 48 slidably fits through a central axial opening 47 in the cap 44 into axial alignment with the ball 45. A cylindrical outer shell or cover 50 fits over the body 12 so that the closed end portion 51 holds the impact member 48 in position. The shell 5® is retained to the body 12 by a screw or pin 53, as shown in FIGURE 1.

With this arrangement, flow of gas between the shell 50 iand the body 12 through the passages 54 provided between the inner wall of the shell 50 and the outer surface of the body 12, passes down and is deflected by the shell end portion 51 through the center of the body 12. The gas flow passes through the perforations 46 of the cap 44 so as to act against the washer 40 deflecting the washer and urging the ball 45 clear of the opening 42. The gas flow then passes up through the openings 22, 20, 18 and out through the recess 14 to the discharge fitting 15. The reversal of the gas pressure on the washer 40, by its build up in the recess 22 due to the restricted flow through the passage 20, causes it to deflect in the opposite direction with the ball again blocking the washer opening 42 and coming sharply into contact with the stem 49 of the impact member 48 urging it against the shell 50. VYhen the assembly 10 is installed with a compressed gas tank, as shown in FIGURE 6 and as will be described in more detail later, a sharp audible impact or knock is imparted to the inner wall of the tank.

The alternative preferred assembly 110, as shown in FIGURE 4, operates in a similar manner. In this assembly a main body 112 is provided with a first tapped recess

3,149,752

114 again adapted to receive a threaded gas outlet fitting 115, a recess 116, a transverse boring 118, an axial recess 122 with an enlargement 124 and a restricted boring 120 between the boring 118 and the recess 122. A pressure valve consisting of a ball 128 and a spring 130 acts to con- 5 trol a boring 126 and is also mounted in the boring 118 and retained by a threaded cap 136 having an O-ring seal 134. In this assembly the recess enlargement 124 is contained within the body 112 and a further boring 125 provides a gas flow passage from the lower end of the body jq to the enlargement 124. A resilient washer 140 having a central opening 142 is mounted in the recess enlargement 124 and a valve in the form of a conical valve head 131 is adapted to alternately seat and unseat on the washer opening 142. The conical valve head 131 is guided and is supported by an elongated stem 132 which slidably fits through a further boring 133 provided in the body 112. A clapper or impact head 130 is mounted on a resilient flat spring 151 secured to the lower end of the body 112 with a connection being made from a bracket 153 secured 20 to the soring 151 to the lower end 135 of the valve stem 132.

This arrangement works in a generally similar manner to that previously described with regard to the construction of FIGURE 1; the flow of gas from the con- 25 tainer is through the boring 125 into the recess enlargement to act on the washer 140 and the valve head 131. The flexing of the washer 14Θ and the lifting of the valve head 131 acts to flex the spring 151 and the release of the gas flow pressure by the raising of the valve head 30 131 causes the stem 132, to sharply descend so that the resiliency of the spring 151 brings the impact head or clapper 150 into contact with the inner wall of the container. In the embodiments shown these warning device assemblies 10, 119 are supported inside the re- 35 spective tanks 180, 182, as shown in FIGURES 6 and 7, by metal tubes 184 connected to the gas outlet fittings 15.

While for some industrial applications it is necessary only to connect the other end of the tubes 184 to the existing valve control 'arrangements, this will result in ⁴⁰the warning devices operating at all times when gas is caused to flow from the tanks regardless of the pressure within the tank. Further, for such complete flow arrangements it is not absolutely essential to include the pressure valve arrangements 28, 30, 128, 139 although 45 they are preferable to ensure an adequate gas flow since, as noted, the openings or orifices 20, 120 leading from the recesses 22, 122 are preferably relatively small or restricted for the efficient operation of the impact causing members. 50

For other applications, and particularly when the present devices are utilized as an audible means of advising a diver as to the pressure remaining in his tank, it is necessary to provide a pressure controlled flow valve, as shown in FIGURE 8. For the present examples it 55 will be understood that both embodiments shown in FIGURES 6 and 7 are provided with such an arrangement. It. will also be understood that the warning arrangements shown could be varied in construction, the main requisite in accordance with the invention being the GO provision of some means actuated by the gas flow as described and capable of generating an audible impact or vibration which is transmitted to the inner wall of the container.

The valve assembly shown in FIGURE 8 consists es- 65 sentially of an outer tube 209 which surrounds the supporting tube 184 connected to the assembly 19, or 119, a passageway 202 leads from the outer tube 290 so as to intersect the air passage 204 in the valve body 296 leading from the tube 184, and a valve spindle 298 having a 70 conical valve seat 219 is spring biased by springs 212, 214 so as to close off a passage 215 leading to the passageway 202 when the pressure has been reduced to the reserve pressure or under.

As shown, the valve 206 is bored transversely to pro- 75 vide a recess 230 which is tapped as indicated at 232 and the valve spindle 208 is mounted for sliding movement in a valve supporting sleeve 234 threadably engaged in the recess 230. The sleeve 234 includes an annular recess 236 and a sealing O-ring 238 is mounted in this recess to provide a gas-tight seal about the valve spindle 298.

For the preferred purpose, it is desirable that the last inward movement of the valve stem, say under pressure conditions from about 700 p.s.i. to the reserve pressure, say 350 p.s.i. be appreciable so that the position of the valve spindle, that is the protruding end portion 209, relative to the exterior of the valve housing 206, will give a visual indication as to the pressure of the gas remaining, particularly when the reserve pressure is drawing near i.e. from 700 to 350 p.s.i. Accordingly the two springs 212, 214 are selected so that the spring 212 is relatively stronger than the spring 214. Also, in the preferred construction shown the portion of the valve spindle 288 supporting the spring 214 is provided with a tubular spacer 240 so that spring 214 cannot be completely crushed. For example, let us assume that the valve spindle portion 209 is fully extended, as indicated at B, under 2300 p.s.i. At 700 p.s.i. it is extended as indicated at A, and from 700 p.s.i to 350 p.s.i. it moves to the position drawn in solid lines. This gives an immediate visual check when the gas supply is near the reserve level. When the reserve level is being used, an audible warning signal is emitted by the container wall.

As will be appreciated with regard to underwater breathing apparatus, when the gas pressure is anywhere from the full pressure, say about 2000 to 2500 p.s.i. depending on the particular apparatus, down to the desired reserve pressure, say about 350 p.s.i., the springs 212, 214 are compressed leaving the passage 215 to the outer tube 209 clear, which means that the gas supply is drawn from both the tubes 200 and 184. The gas flow required to operate the warning device is accomplished only when at least a substantial part of the gas supply is being drawn solely through the tube 184. Accordingly, when the pressure drops to the predetermined reserve level, the spring 214 acts against the valve spindle 298 to seat the valve head 219 and the reserve supply is drawn through the tube 184 which causes the warning devices 10 or 110 to go into action. As the flow passage through the respective devices 10 and 11© is relatively small the loaded pressure valves previously described are used to provide sufficient flow for breathing.

_ It will be appreciated that the present invention provides a means of warning the diver that the reserve supply is being tapped and that this arrangement does not require any manual actuation or adjustment on the part of the diver, as is common in the prior art reserve apparatus.

In order that damage be avoided to the warning devices when the tanks are being filled, it is preferable that a check valve be provided between the respective devices and the discharge outlet fitting through which the gas is usually pumped under pressure in filling the container.

In the construction shown, this check valve is incorporated in the valve 206 and consists of a ball 250 kept in place by a spring 252. As previously mentioned, this check valve couid be anywhere in the tubes 184 or in the housing devices themselves.

It will also be appreciated that the valve construction shown in FIGURE 8 lends itself admirably to prechecking of the warning devices under all pressures since it is merely sufficient to manually depress the valve spindle portion 209. This is particularly useful when the apparatus is employed in connection with underwater breathing arrangements.

As is shown in FIGURES 6 and 7, the tubes or conduits 184 supporting the warning devices of the invention are metal and are formed so as to support the respective warning devices 19 or 11© in contact with the inner wall of the gas containers. The entire assembly is so designed

3.149.752 that it can be readily inserted through the usual neck opening of the tank and retained in position by threaded engagement of the valve body 206 in the usual manner. While it is not illustrated in detail, the usual shut-off valve is included and controlled by a handwheel 270, the end 5 of the valve stem 272 being shown in FIGURE 8.