US3469597A

US3469597A - Safety device for limiting the amount of gas discharged from a container containing a liquefied gas to a predetermined volume

Info

Publication number: US3469597A
Application number: US680072A
Authority: US
Inventors: Luigi Bagnulo
Original assignee: Individual
Current assignee: Individual
Priority date: 1966-11-07
Filing date: 1967-11-02
Publication date: 1969-09-30
Anticipated expiration: 1986-09-30
Also published as: FR1541625A; BE705543A; GB1209164A; SE327118B; DE1551568A1; NL152650B; NL6714825A; ES346788A1

Abstract

1,209,164. Liquefied gas-storage containers. L. BAGNULO. 7Nov., 1967 [1 Nov., 1966], No. 49637/67. Heading F4P. [Also in Division F2] Means for discharging a predetermined volume of gas from the gas space of a liquefied gas, e.g. petroleum gas storage cylinder 3, Fig. 1, when a two-position discharge valve 21 is opened by moving an external lever 13 from its closed to open position shown in Fig. 3 comprises a float 40 which when the lever 13 is in the open position is latched to a rod 26 extending through the float and having its upper square end 25, Fig. 4, in sliding engagement with a squaresectioned chamber 24 formed in the lower end of the valve 21 and carrying an abutment 36 which when the float 40 sinks a certain distance, irrespective of the liquid level, releases a valveholding pin 30 thereby allowing the valve 21 to be closed by a spring 19 even though the lever 13 remains in the open position. The lever 13 is fixed to an arbor 12 which projects through a fixed member 14 and has a square end 16 slidable in a recess in the upwardly spring-biased head 17 of a shank 20 integral with valve 21. The upper end of the head 17 has diametrically opposed cam lugs 18, 18<SP>1</SP>, Fig. 5, which when the lever, arbor and head are rotated ride over lugs 15, 15<SP>1</SP> on fixed member 14 resulting in opening of valve 21 to a position in which a notch 37 is engaged by the pin 30. The rotational movement of the valve when being opened is transmitted to the rod 26, which after a 90 degrees turn is latched to the float by engagement of diametrical longitudinal extending ribs thereon with spring clips on the float and the rod is thus moved downwardly by the float as the liquefied gas vaporizes until the abutment 36 strikes a lever 33 to withdraw the pin 30 and allow valve 21 to be closed by its spring 19. To effect a further discharge of gas lever 13 is moved from its open to its closed position resulting in rod 26 being rotated 90 degrees and unlatched from the float 40 and returned by its spring 49 so that its square end 25 is near the upper end of chamber 24 in valve 21 and the lever 13 is then turned to the valveopen position. In a modification the upper square end of the rod 26, Fig. 8, is in direct sliding engagement with the arbor 53, and the two-position valve 55 is unseated by an arm 56a of a three-armed lever 56 having an arm 56c engaging a cam slot 51 in an extension 52 of the arbor 53. The third arm 56b when engaged by the abutment 36 on rod 26 in its lower position rotates lever 56 to close the valve 55. As in the previous embodiment rod 26 becomes latched to the float when the manual lever 54 is turned from the valve-closed to valve-open position and the rod remains latched until the lever is returned to the valve-closed position. (For Figures see next page.)

Description

3,469,597 HARGED Sept. 30, 1969 BAGNULQ SAFETY DEVICE FOR LIMITING THE AMOUNT OF GAS msc FROM A CONTAINER CONTAINING A LIQUEFIED GAS TO A PREDETERMINED VOLUME 4 Sheets-Sheet 1 Filed NOV. 2, 1967 3,469,597 HARGED FROM A CONTAINER coummxue A LIQUEFIED GAS Sept. 30. W69 L. BAGNULO SAFETY DEVICE FOR LIMITING THE AMOUNT 05 GAS DISC TO A PREDE'I'ERMIN-BD VOLUME 4 Sheets-Sheet 2 Filed NOV. 2, 1967 -VAI m Sept. 30, 1969 BAGNULO 3.469597 SAFETY DEVICE FOR LIMITING THE AMOUNT OF GAS DISCHARGED FROM A CONTAINER CONTAINING A LIQUEFIED GAS TO A PREDETERMINED VOLUME Filed Nov. 2, 1967 4 Sheets-Sheet 5 9t- 30. .69 L.- BAGNULO 3,469,

SAFETY DEVICE FOR LIMITING THE CLINT 0F GAS DISCHARGED FROM A CONTAINER CONTAINING A LIQUBFIED GAS To A PREDETERUINBD VOLUME Filed Nov. 2, 1967 4 Sheets-Sheet 4 United States Patent O 3,469,597 SAFETY DEVICE FOR LIMITING THE AMOUNT OF GAS DISCHARGED FROM A CONTAINER CONTAINING A LIQUEFIED GAS TO A PRE- DETERMINED VOLUME Luigi Bagnulo, Via A. Volta 18, Milan, Italy Filed Nov. 2, 1967, Ser. No. 680,072 Claims priority, application Italy, Nov. 7, 1966, 782,751/66 Int. Cl. F16k 21/16; F17c 7/02, 9/02 US. Cl. 137-209 14 Claims ABSTRACT OF THE DISCLOSURE A safety device for limiting the amount of gas discharged from a container containing a liquefied gas to a predetermined volume after each opening of a gas discharge valve connected to the container and including a float floating on the liquefied gas in the container and following the liquid level variations during discharge of gas therefrom, and an intermediate member connectible to the float for movement therewith when the valve means is moved to an open position and cooperating with the valve means to move the latter to a closed position when the float and the intermediate member connected thereto has moved during discharge of gas downwardly a predetermined distance.

BACKGROUND OF THE INVENTION The present invention relates to a safety device for limiting the amount of gas discharged from a container containing a liquefied gas to a predetermined volume after each opening of a gas discharge valve connected to the container. Such a safety device will prevent after opening of the valve complete discharge of the gas from the container when due to an oversight the valve is not manually closed again to prevent discharge of gas from the container beyond a desired volume.

It is an object of the present invention to provide for such a safety device which will automatically close the gas discharge valve after a predetermined amount of gas has been discharged from the container without requiring the operator to close the valve.

It is a further object of the present invention to pro vide for a safety device of the aforementioned kind which is composed of relatively few and simple parts and which will operate in a foolproof manner during extended use.

SUMMARY OF THE INVENTION With these objects in view, the safety device according to the present invention for limiting the amount of gas discharged from a container containing a liquefied gas to a predetermined volume mainly comprises valve means connected to the container and including a valve body movable between an open and a closed position, operating means operable from the exterior of the container for moving the valve body between the positions thereof, a float adapted to float on the liquefied gas in the container and to follow the liquid level variations during discharge of gas therefrom, an intermediate member movable from a starting position in one direction along a limited stroke and back to the starting position, means connecting the intermediate member to the float regardless of the position of the latter during movement of the valve body by the operating means from the closed to the open position and for disconnecting the ice member from the float during reverse movement of the operating means so that the member when connected with the float will move during discharge of gas from the container in the one direction away from its starting position, control means cooperating with the intermediate member and the valve body for moving the latter to the closed position when the float during discharge of gas has been lowered through a predetermined distance and thereby moved the intermediate member connected thereto through this distance in the one direction so as to limit the amount of gas discharged from the container after opening of the valve means, and means cooperating with the intermediate member for moving the latter back to its starting position when the operating means is moved in said reverse direction to thereby disconnect the intermediate member from the float.

In a preferred construction, the device includes also arresting means movable between an active position and an inactive position and cooperating in the active position with the valve body to maintain the latter in the open position and the control means include biasing means cooperating with the valve body to yieldably maintain the latter in the closed position and means between the arresting means and the intermediate member to move the arresting means to the inactive position when the intermediate member has moved together with the float in the one direction through the predetermined distance to thereby free the valve body to move under the influence of the biasing means cooperating therewith to the closed position. In this construction, the operating means preferably comprise an operating member turnably mounted on the valve means and calm means connected to the operating member and cooperating with the valve body for moving the latter at least from the closed to the open position.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially sectioned side View of a container containing a liquefied gas and the safety device according to the present invention incorporated therein;

FIG. 2 is an axial cross section through the safety device according to the present invention and showing the device in its closed position;

FIG. 3 is an axial cross section similar to FIG. 2 and showing the device in its open position;

FIG. 4 is a partial view in axial cross section and showing the valve means of the safety device and elements cooperating therewith to an enlarged scale and in the open position of the valve means;

FIG. 5 is an exploded perspective view of cam means incorporated in the safety device;

FIG. 6 is a cross section taken along the line VI-VI of FIG. 1 and being drawn to an enlarged scale and showing the intermediate member connected to the float;

FIG. 7 is a cross section similar to FIG. 6 and showing the intermediate member disconnected from the float;

FIG. 8 is an axial cross section through another embodiment of the safety device according to the present invention and showing the same in its closed position; and

FIG. 9 is an axial cross section similar to FIG. 8 and showing the device in its open position.

3 DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, and more specifically to FIGS. 1-7 of the same, it will be seen that the safety device according to the present invention illustrated in these figures includes valve means comprising housing means composed of a housing member 1 formed with an axial bore therethrough which in a lower portion of the housing member 1 is enlarged to form a chamber 6 coaxial with the bore 5. The chamber 6 is substantially closed at its lower end by a housing member 9 coaxially arranged with the housing member 1 and screwed into a cavity of enlarged diameter coaxially arranged with the chamber 6 below the latter. The member 9 is formed with a bore extending in axial direction therethrough and forming at its slightly enlarged lower end portion thereof valve seat 11. The housing member 1 is formed at the outer periphery of a lower portion thereof with a screw thread 2 by means of which the housing member 1 is threadingly connected in a corresponding opening formed for instance in an upper wall portion of a container 3 which may have, as for instance shown in FIG. 1, a substantially cylindrical form and which is adapted to contain a liquefied gas 4 under pressure, for instance liquefied natural gas and filling the container up to a certain level as indicated in FIG. 1.

The housing member 1 is further formed with a discharge passage 7 communicating at an inner end thereof with a lower portion of the chamber 6 and extending through a lateral projecting portion of the housing member 1 which is formed at the outer end with a screw fitting 8 for connecting a gas delivery pipe or the like to the outer end of the discharge passage 7.

A valve body 21 is arranged coaxially with the bore 10 through the member 9 movable in axial direction with respect to the valve seat 11 at the bottom end of the member 9 between an open position as shown in FIGS. 3 and 4 and a closed position as shown in FIG. 2, in which a sealing gasket 23 coaxially arranged with the valve body 21 in a cavity at the upper end of the latter engages the valve seat .11 to prevent flow of gas from the interior of the container 3 through the bore 10 and the chamber 6 into the discharge passage 7.

Operating means are provided to move the valve body 21 at least from the closed to the open position, and the operating means may include, as best shown in FIG. 4, an operating member or handle 13 located at the outer end of the housing member 1 and a stem 12 connected to the handle 13 and extending from the handle 13 through the bore 5 fluid-tightly sealed and turnably guided therein into the chamber 6. The stem 12 has at its lower end a portion 16 of non-round, preferably square, cross section which extends with a slide fit into a correspondingly shaped axially extending cavity formed in the upper substantially cup-shaped portions 17 of a connecting member located in the cavity 6 and extending with a coaxial stem portion 20 through and beyond the axial bore 10 and being fixedly connected at its lower end to the valve body 21 by being for instance formed at its lower end portion with an outer screw thread which is threaded in a corresponding screw-threaded central bore in the upper portion of the valve body 21. During turning of the handle 13 in one or the other direction, the valve body 21 therefore will be turned in the corresponding direction while being free to move with the connecting

member

17, 20 in axial direction relative to the stem 12 connected to the handle 13. Biasing means, which may be in the form of a coil compression spring 19', are located in the chamber 6 about part of the connecting

members

17, 20 abutting with the lower end thereof against an upper surface of the housing member 9 and with its upper end against a shoulder face of the cupshaped portion 17 of the connecting member and being biased to move the latter and the valve body 21 connected thereto in upward direction, that is to move the valve body to its closed position in 4 which the gasket 23 engages the valve seat 11. The stem 20 is formed in its peripheral surface with at least one, and preferably a plurality of longitudinally extending grooves 22 so as to permit gas from the interior of the container 3 to flow through the bore 10 into the chamber 6 and from there through the discharge passage 7 to the outside of the container when the valve body 21 is in the open position as shown for instance in FIG. 4. The spring 19 is biased to yieldably maintain the valve body 21 in its closed position.

To move the valve body 21 during turning of the handle 13 from its closed to its open position, the device includes further cam means comprising an annular member 14 fixedly mounted in an upper portion of the chamber 6 and having a pair of downwardly extending and diametrically oppositely arranged camming portions 15 and 15', as best shown in FIG. 5, and a second pair of diametrically oppositely arranged camming portions 18 and 18' in form of prong-shaped projections projecting upwardly from the upper surface of the cup-shaped portion 17 of the connecting member and adapted to cooperate with the fixed

camming portions

15 and 15 during turning of the handle 13 to depress the connecting

members

17, 20 against the action of the compression spring 19 to move thereby the valve body 21 to the open position, as shown in FIG. 4, when the apexes of the camming portions 15 and 15' are respectively aligned with the

camming portions

18 and 18 and to free the connecting

member

17, 20 to move in upward direction under the action of the compression spring 19 to thereby move the valve body 21 to its closed position when the

camming portions

18 and 18 have been moved past the camming portions 15 and 15'.

The embodiment according to the present invention illustrated in FIGS. 1-7 includes further arresting means for arresting the valve body 21 in its open position. The arresting means comprise an arresting pin 30 having an enlarged diameter portion which is slidably guided in a cylindrical housing 31 screwed into an opening in an L- shaped bracket 28, the longer leg of which extends spaced from and parallel to the axis of the valve body 21 and the shorter upper leg of which is connected, for instance by a screw 29, to the bottom end of the housing member 1. A compression spring 32 located in the cylindrical hous ing 31 engages with opposite ends thereof the enlarged diameter portion of the arresting pin 30 and a closure cap screwed onto the open rear end of the cylindrical housing 31, so as to bias the arresting pin 30 towards the valve body 21. The latter is provided intermediate its ends with a cam groove 37 vertically aligned with the front end of the arresting pin 30 when the valve body 21 is in its open position, as for instance shown in FIG. 4, so that the front end of the arresting pin will engage into the cam groove 37 to hold thereby the valve body 21 in its open position. It is pointed out that the depth of the cam groove 37 decreases from its maximum depth shown in FIG. 4 in direction of turning the handle 13 towards the closed position, i.e., a position in which the valve will close, and becomes zero in the latter position, so that by turning the handle 13 to the closed position, the arresting pin 30 will be pushed back against the action of the compression spring 32 so that when the handle 13 i moved to the closed position the valve body 21 will be free to move upwardly to its closed position under the action of the compression spring 19.

In order to move the valve body 21 from its open to its closed position without actuating the handle and after a predetermined volume of compressed gas has been discharged from the container, the device of the present invention includes float 40 adapted to float on the liquefied gas 4 in the container 3 and to follow the level variations of the liquefied gas during discharge of gas from the container, an intermediate member 26 which, in the embodiment shown in FIGS. 1-7, is in the form of an elongated rod coaxially arranged with the valve body 21 and extending with an upper portion 25 of non-round and preferably square cross-section with a slide fit into a correspondingly shaped cavity 24 formed in the bottom end portion of the valve body 21 so as to be connected to the latter for turning movement about its axis while being free to move relative to the valve body in axial direction from an upper starting position, as for instance shown in FIG. 4 along a limited stroke downwardly to a position as for instance shown in FIG. 2.

The arrangements includes further means connecting the intermediate member to the float, regardless of the position of the latter, during movement of the valve body 21 by the operating means including the handle 13 from the closed to the open position of the valve and for disconnecting the intermediate member 26 from the float 40 during reverse movement of the operating means so that the intermediate member 26, when connected with the float 40, will move during discharge of gas from the container 3 in downward direction from its starting position as shown in FIG. 4. The aforementioned connecting means for connecting the intermediate member 26 to the float 40 preferably comprise, as shown in FIGS. 6 and 7, a pair of

spring clips

45 and 46 arranged diametrically opposite to each other in a central bore extending through the float 40 and being connected at one end in any convenient manner to the bore surface. The intermediate member or rod 26 extends with considerable clearance through the aforementioned central bore of the float 40 and the rod has an oblong cross section or is provided at diametrically opposite sides with a pair of longitudinally extending

ribs

47 and 48 so that the rod 26, when the valve is turned by the handle 13 to its closed position, will assume the position as shown in FIG. 7 in which the

ribs

47 and 48 are disengaged from the

spring clips

45 and 46 so that the rod 26 and the float 40 may move freely relative to each other and so that when the valve is turned by the handle 13 to its open position, the rod 26 with its ribs will assume the position as shown in FIG. 6 in which the ribs engage the

spring clips

45 and 46 so that the rod 26 will be, by the frictional forces thus developed, connected to the float for movement therewith in axial direction.

To prevent, during turning of the rod 26 between the positions as shown in FIGS. 6 and 7, the float 40 from turning with the rod before the

ribs

47 and 48 on the rod are properly engaged with or disengaged from the

spring clips

45 and 46, the float 40 is provided with a pair of guide portions or noses 41 and 42 projecting diametrically opposite each other from the peripheral surface of the float and cooperating with guide grooves 43, 44, respectively, provided in a tubular guide member 38 guiding the float for movement in axial direction and being connected at the upper end in any convenient manner to a bottom portion of the housing member 1, as best shown in FIGS. 2 and 3. The guide tube 38 is provided along its length with a plurality of large openings 39 so that liquefied gas in the container 3 may freely pass through the openings 39 into the interior of the guide tube 38. Preferably, the

guide tube 38 is surrounded with a cylindrical wire netting 50 preventing impurities in the form of small particles which may be contained in the liquefied gas 4 to penetrate into the interior of the tube and thereby increase the friction between the inner tube surface and the outer surface of the float.

The arrangement includes further control means cooperating with the intermediate member or the rod 26 and the valve body 21 for moving the latter to the closed position independent from an operator, when the float 40 during discharge of gas from the container 3 has been lowered through a predetermined distance and thereby moved the intermediate member 26 connected thereto through this distance in downward direction so as to limit the amount of gas discharged from the container after opening of the valve to a predetermined volume in a fully automatic manner. The control means in the embodiment illustrated in FIGS. 1-7 include a transverse member or disk 36 fixed to an upper portion of the rod 26 and cooperating with the lower portion of a lever 33 pivoted at the upper end at 34 to a small bracket extending laterally from the bracket 28. The lever 33 is connected intermediate its ends to a pin 35 extending through the enlarged diameter portion of the arresting pin 30 and a slot in the cylindrical housing 31 in such a manner that the lever under the action of the compression spring 32 in the housing 31 will be obliquely inclined to the axis of the rod 26 and remain in engagement with the disk 36. The inclination of the lever 33 and the diameter of the disk 36 are chosen in such a manner that when the intermediate member or rod 26 moves downwardly with the float 40 connected thereto through a predetermined distance, the lever 33 will be turned about the pivot pin 34 in clockwise direction from the position shown in FIG. 3 to the position shown in FIG. 2 to thereby retract the pivot pin 30 from the cam groove 37 so as to free the valve body 21 to move in upward direction to its closed position under the influence of the compression spring 19.

The device includes further means which may be in the form of a compression spring 49 about an upper portion of the rod 26 and abutting with opposite ends thereof against the bottom face of the disk 36 and the top face of a transverse wall through the guide tube 38. Spring 49 cooperates with the intermediate member 26 for moving the latter back to its starting position, i.e., in engagement with the end face of the cavity 24 in the valve body 21 when the handle 13 is moved to the closed position in which the rod 26 is turned to the position as shown in FIG. 7 and thereby disconnected from the float.

The operation of the device described above will be as follows:

Assuming the valve is in the open position, further discharge of gas from the container 3 may be stopped by manually turning the handle 13 to its closed position, whereby the valve body 21 is likewise rotated through the same angle and becomes disengaged from the arresting pin 30 since, as described above, the depth of the cam groove 31 decreases in direction of rotation of the handle 13 and the valve body 21 connected thereto for rotation therewith to the closed position and becomes zero in the latter position so that the valve body is freed to move under the influence of the compression spring 19 in upward direction in engagement with the valve seat 11 and further discharge of gas from the container is stopped. During such turning of the handle 13, the rod 26 will be turned to the position as shown in FIG. 7, that is to be disengaged from the float, and move upwardly relative to the latter under the influence of the spring 49 until the upper end of the rod 26 is stopped by the end face of the cavity 24. When it is now desired to again draw gas from the container 3, the operator will turn the handle 13 from its closed to its open position and during this turning movement the stem 12, the connecting

member

17, 20, the valve body 21 and the rod 26, all connected to each other for simultaneous turning, will turn through a corresponding angle. During this turning of the connecting

member

17, 20, the prong-shaped cam portions 18 and 18' projecting upwardly from the cup-shaped portion 17 of the connecting member will cooperate with the camming portions 15 and 15' of the cam 14 fixedly mounted in the chamber 6 to move the connecting member and the valve body 21, fixed thereto for movement in axial direction, downwardly to a position in which the cam groove 37 will be aligned with the arresting pin so that the latter will hold the valve body 21 in its lower open position, while the camming portions 18 and 18' move beyond the camming portions 15 and 15'. When the handle 13 is moved to the open position, the valve body 21 will therefore be held in its lowered open position as shown in FIGS. 3 and 4 only by the arresting pin 30 engaged in the cam groove 37. During turning of the handle 13 to the open position, the intermediate member 26 is turned to the position as shown in FIG. 6

in which the intermediate member or rod 26 is coupled with the float 40 for movement in axial direction with the latter.

When the elements of the device are in the position relative to each other as described above, gas forming in the upper portion of the container 3 from the liquefied gas 4 may flow freely from the interior of the container through the longitudinal grooves 22 in the stem 20 into the chamber 6 to pass from there through the discharge passage 7 to any utilization apparatus connected to the pipe coupling 8, while the liquid level in the container is gradually lowered and the float 40 as well as the rod 26 connected thereto will move in downward direction. It should be noted that the force of the compression spring 49 is only suflicient to lift the rod 26 alone, but the force of this compression spring will be overcome when the float 40 is connected to the rod, i.e., the spring 49 will not prevent lowering of the rod 26 and the float connected thereto during lowering of the liquid level in the container 3.

As the rod 26 is lowered, the disk 36 fixedly connected to the rod will act on the lever 33 to turn the latter gradually in clockwise direction about its pivot pin 34 so that after the rod 26 has moved downwardly a predetermined distance, the arresting pin 30 will be disengaged from the cam groove 37 and the valve body 21 be freed to move under the action of the compression spring 19 to its closed position to thereby automatically stop further discharge of gas from the container. The amount of gas delivered is a function of the stroke traveled by the disk 36 and can be preset by adjusting the ratio between the arms of the lever 33, the diameter of the disk 36 and other parameters.

FIGS. 8 and 9 illustrate another embodiment of the safety device according to the present invention. In this embodiment, the valve body 55 and the discharge passage through the housing member controlled by the valve body is located laterally of the bore through which the stem 53 connected to the operating member or knob 54 extends. The stem 53 is in its lower portion formed with an elongated cavity extending in axial direction and, preferably, of square cross section, in which the upper portion of corresponding cross section of the intermediate member or rod 26 extends with a slide fit so that the rod 26 is again connected to the stem 53 for turning movement therewith while being free to move relative thereto in axial direction. The rod 26 extends as described in connection with the first embodiment through an axial opening of the float 40 and is connectible with and disconnectible from the latter in the manner as described in connection with the first embodiment. A compression spring is again coiled about a portion of the rod 26 and cooperates with the latter to bias the rod in upward direction so that the rod, when disconnected from the float, will move under the force of the compression spring coiled thereabout to its starting position as shown in FIG. 9.

The control means which cooperate with the intermediate member or rod 26 and the valve body 55 are in this embodiment constituted by a three-armed lever 56 which is pivoted about a fixed pivot axis. The arm 56a of the lever 56 is connected, in a manner not shown in the drawing, to the valve body 55, for instance by a pin fixed to the arm 56a and extending through a slot in the downwardly extending portion of the valve body 55 and arranged transverse to its axis, whereas the arm 56b is arranged to interfere with the stroke of the disk 36 fixed to an upper portion of the rod 26 and the third arm 56c is engaged in a cam slot 51 formed in a cylindrical sectoral extension 52 integral with the stem 53 connected to the handle 54 for rotation therewith.

The embodiment illustrated in FIGS. 8 and 9 will operate as follows:

By turning the handle 54 from the closed position to the open position, the cam sector 52 is turned through the same angle and the cam slot 51 extends spirally through the sector 52 in such a direction that during this movement of the handle 54 the valve body 52 is brought from the closed position, as shown in FIG. 8, to the open position, as shown in FIG. 9, since the tail portion of the arm 56c moving over the profile of the cam slot is brought to the upper end of the cam slot. Simultaneously, the rod 26 is engaged with the float 40 as described in connection with the first embodiment. When, now, during discharge of gas from the container, the level of liquefied gas in the container drops through a predetermined distance, the float and the rod 26 connected thereto will move downwardly until the transverse disk 36 engages the tail end of the arm 56b of the lever 56 so that the latter will move the valve body 55 connected to the arm 56a of the lever from the open position, as shown in FIG. 9, to the closed position, as shown in FIG. 8.

Whenever it is desired to deliver gas again from the container, the handle 54 should first be restored to its closed position and then be brought to the open position, in the same manner as in the previously described embodiment, so that the rod 26 will become disconnected from the float and be free to move to its starting position under the influence of the compression spring coiled about an upper portion of the rod.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of safety devices for limiting the amount of gas discharged from a container containing a liquid gas to a predetermined volume after each opening of a valve connected to the container differing from the types described above.

While the invention has been illustrated and described as embodied in a safety device for limiting the amount of gas discharged from a container to a predetermined volume and including a float adapted to float on the liquefied gas in the container and means connecting the float to the valve for automatically closing the latter after discharge of a predetermined volume of gas from the container and corresponding dropping of the liquid level therein, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characeristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

I claim:

1. A safety device for limiting the amount of gas discharged from a container containing a liquefied gas to a predetermined volume comprising, in combination, valve means connected to the container and including a valve body movable between an open and a closed position; operating means operable from the exterior of the container for moving said valve body at least from one to the other of the positions thereof; a float adapted to float on the liquefied gas in the container and to follow variations of the level of the liquefied gas during discharge of gas from the container; an intermediate member movable from a starting position in one direction along a limited predetermined stroke and back to its starting position; means connecting said intermediate member to said float regardless of the position of the latter during moving of said valve body by said operating means from said closed to said open position and for disconnecting said member from said float during reverse movement of said operating means so that said member, when connected with said float, will move during discharge of gas from the container in said one direction away from its starting position; control means cooperating with said intermediate member and said valve body for moving the latter to said closed position when said float during discharge of gas has been lowered through a predetermined distance and thereby move said intermediate member connected thereto through said distance in said one direction so as to limit the amount of gas discharge from said container after opening of said valve means; and means cooperating with said intermediate member for moving the latter back to its starting position when said operating means is moved in said reverse direction and thereby disconnects said intermediate member from said float.

2. A safety device as defined in claim 1, wherein said means for moving said intermediate member back to its starting position comprise biasing means which are biased to yieldably maintain said intermediate member in its starting position.

3. A safety device as defined in claim 2, wherein said intermediate member is in the form of an elongated rod movable in axial direction and turnable about its axis by said operating means for connecting said rod with and for disconnecting it from said float.

4. A safety device as defined in claim 3, wherein said valve means comprises housing means formed with a bore therethrough coinciding with the axis of said rod and with a discharge passage laterally of said bore and having an inner portion forming a valve seat engaged by said valve body in said closed position of the latter, said operating means including a stem extending fluid-tightly sealed through said bore turnably about said axis, said rod being connected to said stem for turning therewith about said axis and movable in axial direction relative thereto, said control means including lever means turnable about a fixed pivot axis and connected at one end to the valve body, and a transverse member fixed to said rod and adapted to engage said lever means when said rod has been moved by said float from its starting position through said predetermined distance to turn said lever means in a direction which moves said valve body to its closed position in engagement with the valve seat.

5. A safety device as defined in claim 4, and including cam means having a cam face and being connected to said stem for turning therewith about said axis and cooperating with said lever means for turning the latter in the direction which moves said valve body to its open position.

6. A safety device as defined in claim 5, wherein said lever means includes a three-armed lever, one arm of which is connected to said valve body, the second arm of which engages said cam face, and the third arm of which is located in the path of said transverse member so that the latter engages said third arm during movement of said rod in said one direction through said predetermined distance to thereby move said valve body to said closed position.

7. A safety device as defined in claim 3, wherein said rod extends substantially coaxially arranged with said float with clearance through an axial bore in the latter, and wherein said means for connecting said rod to said float comprise resilient means in said bore, said rod having a cross section to engage and compress said resilient means during turning of the rod about its axis to a first position to connect the float to the rod and to disengage the rod during its turning to a second position from said resilient means to free said rod and said float for relative movement with respect to each other.

8. A safety device as defined in claim 7, and including guide means cooperating with said float for guiding the same in axial direction but preventing said float from turning about its axis.

9. A safety device as defined in claim 1 wherein said operating means comprises an operating member turnably mounted on said valve means and cam means connected to said operating member and cooperating with said valve body for moving the latter at least from said closed to said open position.

10. A safety device as defined in claim 9, wherein said operating member is turnable about an axis coaxial with said valve body.

11. A safety device as defined in claim 10, and including arresting means movable between an active and an inactive position and cooperating in said active position with said valve body to maintain the latter in said open position, said control means including biasing means cooperating with said valve body to yieldably maintain the latter in said closed position and means between said arresting means and said intermediate member to move said arresting means to said inactive position when said intermediate member has moved together with said float in said one direction through said predetermined distance to free said valve body to move under the influence of said biasing means cooperating therewith to said closed position.

12. A safety device as defined in claim 11, wherein said arresting means comprise a peripheral cam groove, in said valve body and a spring pressed arresting pin guided for movement in and out of said cam groove, and wherein said means between said arresting means and said intermediate member comprise a lever pivoted at one end about a fixed pivot axis and being connected intermediate its ends to said arresting pin, and means on said intermediate member adapted to engage said lever in the region of its free end to turn said lever about its pivot axis in the direction to withdraw the pin from said cam groove when said intermediate member is moved through said predetermined distance in said one direction.

13. A safety device as defined in claim 12, wherein said valve means include housing means formed with an axial bore therethrough coinciding with said turning axis of said operating member and having an outer and an inner end, a chamber coaxial with said bore intermediate the ends of the latter, a discharge passage communicating with said chamber, a valve seat at the inner end of said bore and adapted to cooperate with one end of said valve body, said operating means comprising a stem, connected to said operating member and extending fluid-tightly sealed from the outer end of said bore into said chamber, a connecting member extending from said chamber through said inner end of said bore and being connected at one end to said stem for turning therewith about the turning axis and for movement relative thereto in axial direction and at the other end to said valve body, and said cam means comprising at least two camming portions extending in axial direction toward each other, a first of said two camming portions being fixedly mounted in said chamber, and the second of said two camming portions being mounted on a portion of said connecting member in said chamber, said camming portions engaging each other during turning of said operating member so as to move said valve body to its open position spaced from said valve seat and said camming portions become disengaged from each other during further movement of said operating member so that, when the arresting means are moved to its inactive position, said valve body will be free to move under the action of said biasing means cooperating therewith to its closed position in engagement with said valve seat.

14. A safety device as defined in claim 13, wherein said intermediate member comprises an elongated rod coaxial with said turning axis and connected to the other end of said valve body for turning therewith about said axis and for movement relative thereto in axial direction.

(References on following page) 11 12 References Cited WILLIAM F. ODEA, Primary Examiner UNITED STATES PATENTS DAVID R. MATTHEWS, Assistant Examiner 2,820,419 1/1958 Albertson 137-420 X 2,889,846 6/1959 Glasby et a1 137 420 X 3,082,785 3/1963 Radway 137-386 5 137 420, 429; 251-66, 229, 263