US3828857A

US3828857A - Apparatus for filling and emptying containers for use in firefighting

Info

Publication number: US3828857A
Application number: US00205507A
Authority: US
Inventors: A Mason
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-12-07
Filing date: 1971-12-07
Publication date: 1974-08-13
Anticipated expiration: 1991-08-13

Abstract

A container which may be filled by immersing the lower portion thereof into a fluid and allowing the fluid to enter the container through a main valve and a number of one-way secondary valves in this lower portion. The main valve is connected to a float which closes the valve when a predetermined level of fluid has entered the container. The secondary valves are closed by the action of the fluid when the container is raised from the reservoir of fluid. The main valve is held closed by a latch mechanism which may be tripped from a remote station allowing the valve to open and discharge the fluid from the container.

Description

United States Patent [19 10/1960 Morin .j. 294/69 R Mason 5] Aug. 13, 1974 APPARATUS FOR FILLING AND 3,710,868 l/l973 Chadwick l69/2 A EMPTYING CONTAINERS FOR USE IN FIREFIGHTING Primary Examiner-J-louston S. Bell, Jr. [76] Inventor: Athol James Malcolm Mason, 6 Attorney Agent or Firm-Holman & Stem lngle Ave., Box 298, Taupo, New A Zeakmd {57] ABSTRACT 2 Filed, Dec 7 1971 A container which may be filled by immersing the lower portion thereof into a fluid and allowing the [2]] Appl. No.: 205,507 fluid to enter the container through a main valve and a number of one-way secondary valves in this lower portion. The main valve is connected t o a float which "f 169/5? closes the valve when a predetermined level of fluid [58] Fieid 111 112 has entered the container. The secondary valves are 141/1 5 i 1 7 closed by the action of the fluid when the container is 294/69 169/2 2 raised from the reservoir of fluid. The main valve is held closed by a latch mechanism which may be f tripped from a remote station allowing the valve to g g open and discharge the fluid from the container. 2,956,833 I 22 Claims, 7 Drawing l igures PATENTEUAUGIBISH V 3,828,857

"sum 2 0r 5 v PATENIE mm 3 I974 SHEET 3 OF 5 KKK- PArami-znwsla w 3,828,857

SHEET 9 [IF 5 BACKGROUND OF THE INVENTION This invention relates to apparatus for filling and emptying containers, and has been devised particularly though not solely for use in firefighting.

At present, in many areas such as in forests or bush, effective firefighting is difficult or sometimes impossible, owing to poor roads or lack of roads, distance, topography and lack of local water supplies. Any fire which may break out in such an area, can only be controlled when the fire spreads, and endangers a more accessible area. The only practicable way of fighting such a fire before the fire spreads to more valuable areas, is to employ aircraft and, in particular, a helicopter. Some methods are in use for transporting water or other fire extinguishing materials using a helicopter, but these methods'are generally slow and inefficient, and therefore ineffective.

' provide apparatus for filling and emptying a container,

which will obviate or minimize the foregoing disadvantages in a simple yet effective manner, or which will at least provide the public with a useful choice.

It is also an object of the present invention in a preferred form thereof to provide apparatus for firefighting which will obviate or minimize the foregoing disadvantages in a simple yet effective manner, or which will at least provide the public'with a useful choice.

Accordingly, the invention consists in apparatus for filling and emptying a container, comprising a valve adapted to be mounted in a lower part of such a container, said valve havinga movable valve member, and comprising holding means adapted to hold said movable valve member in the closed position, opening means adapted to allow an opening force to be applied to said movable valve member to open said valve, and closing means adapted to allow a closing force to be applied to said movable valve member to close said valve, the construction and arrangement being such that in use, upon the container being at least partially immersed in a fluid to a suitable depth with said valve open, fluid will enter the container through said valve, and said valve will be closed by said closing force on operation of said closing means, and said valve will be opened, to permit discharge of the container contents, by said opening force on operation of said opening means.

In a further aspect, the invention consists in a container having a valve mounted in a lower part thereof, said valve having a movable valve member, holding means adapted to hold said movable member in the closed position, opening means adapted to allow an opening force to be applied to said movable valve member to open said valve, and closing means adapted to allow a closing force to be applied to said movable valve member to close said valve, the construction and arrangement being such that in use, upon the container being at least partially immersed in a fluid to a suitable depth with said valve open, fluid will enter the container through said valve, and said valve will be closed by said closing force on operation of said closing means, and said valve will be opened, to permit discharge of the container contents, by said opening force on operation of said opening means.

In a still further aspect, the invention consists in apparatus to be used for firefighting adapted to be attached to a hoverable aircraft, said apparatus comprising a container as aforesaid.

BRIEF DESCRIPTION OF THE DRAWINGS One preferred form of the invention will now be described with reference to the accompanying drawings in which,

FIG. 1 and FIG. 2 are cross sectional views of a container according to the preferred form of the invention showing a valve in the base of the container in the open position and in the closed position respectively.

FIG. 3 is a fragmentary view of the release valve trip mechanism FIGS. 4 and 5 are side and front elevational views respectively of an inlet valve according to the invention,

FIG. 6 is an elevation of the control means, and FIG. 7 is a view similar to FIG. 3 illustrating a second tripping mechanism.

DETAILED DESCRIPTION OF THE INVENTION In the preferred form of the invention, as shown in the drawings, a container 1 has a body 2 in the form of a bucket or hopper. The body is provided with upper cross members 3 and lower cross members 4 which extend across the interior of the container adjacent the top and bottom ends thereof respectively. Cables or other like support means 5 are affixed to the body 2 by which the body may be attached to a lifting means, for example, a hoverable aircraft such as a helicopter.

The bottom of the body 2 includes a valve 6 defined by a valve opening 7 having a valve seat in the form of a rubber sealing ring 8 and a movable valve member 9 in th form of a plate. The valve member 9 is fixed to a support such as a shaft 10 which extends vertically through the interior of the container passing a bearing 12 in the cross member 4. The upper end of the shaft 10 is threaded to connect with a member 16 which extends vertically through a bearing 11 in the cross members 3 and terminates in an adjustable stop block 13. Affixed to the cross members 3, adjacent to the bearing 11 therein is a rubber buffer 14 adapted to bear on the stop block 13. The shaft 10 and its extension 16 are thus constrained to move vertically downwards when the valve 6 is fully opened and the stop block 13 bearing against the buffer 14 as shown in FIG. 1, and upwards until the valve 6 is fully closed and valve member 9 bears against the sealing ring 8 as shown in FIG. 2. The stop block 13 is adjustable relative to the shaft 10 and may be raised or lowered to increase the distance between valve seat 8 and the valve member 9 when the valve is fully opened.

A float 15 is affixed to the shaft 10 and is of sufficient buoyancy to support the shaft 10 and the valve member 9 when at least partially immersed in fluid which the container may be adapted to carry.

A recess in the form of a V-groove is provided in the member 16 which has a horizontal bearing surface 17 and an angled guidesurface thereon. A tripping mechanism is affixed to the container and comprises a V- shaped latch member 18 which is pivotally attached to the upper cross members 3 adjacent to the member 16 and pivoted at pivot points 21. An arm 20 is connected 20 is fixed to. a trip wire 19. The trip wire 19 is connected to a remote control, for example, in a helicopter being used to lift a container. The latch member 18 is normally arranged so that one face of the Vee section is normally horizontal providing a bearing surface to engage the bearing surface 17 in the shaft member 16. The arm 20 is adapted to rest against the stops provided on the cross members 3 when the valve 6 is in the open position.

The body 2 of the container l'is provided with overflow holes 28 at various levelsas shown inFlG. 1. Any

' number of which holes commencing at the'lowermost,

may be plugged to vary the liquid carrying capacity of the container to suit the maximum capacity of the lifting means. Adjacent'the lower end of the container 1 rapid filling inlet valves are provided,'each valve comprising a sealing member 22 fixed to a back plate 23. The back plate 23 is mounted with a valve stop member 24. The valve sealing member 22 is affixed to the wall of the body 2 in'a manner such that it covers an inlet opening '25, with the whole assembly beingpivotal inwardly against the natural resilience of the sealing member 22.

To use the container 1 according to the preferred ,form of the invention, forexample, for firefighting using a hoverable aircraft-such as a helicopter, the'container is first secured by means of cables or the like support means 5' to such helicopter and the control end of the trip wire 19 is attached to a remote control located in the helicopter.

The valve 6 in the container is then opened by allowing the valve member 9 to fall away from the valve seat 8. If the bearing surface of the latch member is hearing against the lower bearing suface 17 of the shaft exten sion 10, the valve member 9 is held against the valve seat 8, and thus the valve 6 is held closedasshownin FIG. 2, then the trip wire 19 by operating the remote control is pulled upwards, causing the latch member 18 to be rotated by arm 20 thus releasing the shaft member 16 and allowing the valve member 9 to move downwardly from the sealing member 8 until the stop member 13 comes to rest against the buffer 14.

The container is then at least partially immersed into a body of fluid'it is desired to transport, for example, a lake or reservoir of water or other fire extinguishing liquid when the container -is'being used for firefighting. If .the container is lowered into the body of he fluid, it enters the container through the open valve 6 and through the inlet valve hole 25. When the fluid entering the container reaches the float 15, it causes the float to rise causing theshaft and the extension 16 and the valve member 9 to be raised with it. As theshaft extension member 16 is raised, the latch member 18 is forced to rotate until the recess with the bearing surface 17 is adjacentthe trigger latch member 18. When the valve member 9 has been raised by the float until it bears against and preferably compresses the sealing ring valve seat" 8, the latch member 18 engages the bearing surfaces 17 of the shaft extension 16. The valve 6 is thus closed automatically without the necessity of pulling the trip wire 19.

The container is then lifted from the body of fluid. Any fluid in excess of the desired capacity in the container which may have entered during the loading, will be discharged through those overflow holes 28 which 4 are unplugged as the container is raised. The inlet holes 25 will of course now be covered by their sealingv valve flaps 22 due to the action of the fluid 'now contained within the container. Only that quantity of fluid which is below the lowermost of the unplugged holes 28 will be carried by the container, and thus the maximum carrying capacity of the container may be varied as desired by suitably plugging any numberof the holes 28. As the container is lifted from the body of fluid, the valve 9 is forced downwards by the weight of fluid inside the container, until it bears against the latch member 18 and the bearing surface 17 as shown in FIG. 2. Preferably, this downward movement is very short, and insufficient to separate the valve member 9 from the sealing ring 8.

The container is then supported until it is located over the area into which it is desired to discharge the container contents, e.g., over a fire. The valve 6 is then opened by'pulling thetrip wire 19 and allowing the valve member 9 to fall away from the valve seat 8 in the manner described above. When the valve 6 is opened, the fluid in the container falls through the open valve and onto the desired target area. When empty, the container is then returned to the bodyof the fluid for a further load as desired.

Referring to FIG. 6 the trip wire 19 is connected to a release mechanism 29 which ismounted within the hoverable aircraft. The base 30 is affixed to the aircraft frame in a suitable operable position. A pair of side plates 31 apertured to carry a pivot shaft 32 on which is mounted a sheave 33 carrying an arm 34 which terminates in a foot pad 35. The arm 34 is fixably mounted on the sheave 33 such that pressure on the foot pad 35 by an operator will rotate the arm 34 and the sheave 33 about the pivot shaft 32. The lips 36 of the sheave 33 are notched at 37 to provide an anchor for the cable 19 which terminates in a. cross member 38 adapted to engage the notches 37. A tension spring 39, is provided with one end attached to the side plate 31 at a position substantially vertical below the pivot axis of the sheave 33 and with itsother end attached to the sheave 33 in a manner such that a rotational force is applied to the sheave to maintain the cable 19. under sufficient pressure to prevent the cross member 38 from disengaging the notch 37. The force being much less than the force required to release the trip mechanism in the body 2. The cable 19 is encased in a casing 40 which terminates in a hook member 41 which'is adapted to engage a downwardly turned portion of the base 30. The hook member 41 is maintained in engagement with the base 30 by the rotational force applied to sheave 33. Under normal conditions the release mechanism 29 may be operated by pressure on the foot pad 35 thus rotating the sheave 33 and causing movement of the cable 19 causing the trip mechanism in the container to release overcome the rotational force applied to the sheave 33 by the tension spring 39 and the sheave 33 will rotate in the reverse direction until the crossmember 38 disengages the notches 37 thus allowing the cable 19 and the casing 40 to fall away with the container 2 when the 7 container 2 is released from the aircraft under such conditions.

In an alternative construction, shown in FIG. 7, it is also envisaged that the container described above could be provided with two tripping mechanisms, one adapted to hold the valve closed, and then be operated to allow the valve to open, and the second mechanism adapted to hold the valve open and then be operated to allow the valve to close. This could be achieved, for example, by having each tripping mechanism engageable with one of two V-grooves, similar to the V-groove with bearing surface 17 in the preferred form of the invention, one of the grooves having its bearing surface on its top surface and the other having its bearing surface on its bottom surface. When one groove is release byoperation of its associated tripping mechanism, the other would be automatically engaged on movement of the'shaft. In FIG. 7, the components of the second tripping mechanism bear the same reference numerals with the letter a.

If the invention is being used for firefighting, for example, in conjunction with a helicopter, then a remotely controlled device for injecting an agent, e.g., a wetting agent or fire retarding agent into the water being carried in the container may-be mounted, for example, on a platform attached to the upper cross members 3. The agent is pumped from a storage container, which is attached to the platform by a solenoid operated piston pump. The stroke of the solenoid and piston and, hence, the capacity of the pump, may be varied by means of a moveable stop which intercepts a rocker lever connecting the solenoid to the pump, to ensure that a substantially predetermined proportion of the agent is injected into the water in the container.

The solenoid is activated electrically by a control switch in the helicopter, electric cables being provided to link the solenoid to the control switch.

A further modification within the scope of the invention is to provide a deflector in the form of a funnel or a short piece of tube 26 in the form of a band placed around and concentric with the inlet opening 25. The band extends from just above the bottom opening down to below the level of the valve member 9 at its fully open position. When the water falls from the container immediately after opening, as described above, it is deflected sideways by theupper surface of the open plate. However, when the deflector is fitted the water is deflected downwards on striking the deflector, and thus is concentrated onto a smaller ground area. The deflector may be rigidly fixed to the container, or it may be flexibly fixed thereto such that when the container is placed on the ground, it rests on the plate 7 rather than the lower edge of the deflector, while the deflector has merely to support its own weight as it is raised relative to the body of the container on striking the ground. Yet a further modification would be to provide a remote control raising and lowering means for the deflector so that it may be raised both whenthe container is resting on the ground, and when in use it is desired to provide a less concentrated flow of water from the container.

Although describedabove in relation to firefighting, it is also envisaged that the invention would be used, on a much smaller scale, for example, as a device for measuring or sampling various liquids. In its modified form, being adapted to close automatically when a substantially pre-determined quantity of fluid has entered the container, the invention is particularly suitable for extracting predetermined and measured quantities of fluid from a reservoir of the fluid.

In an alternative construction, the release mechanism 29 which is mounted within the helicopter may be replaced by a solenoid mounted on the upper cross members 3 of the body 2 to operate the latch trip mechanism. The solenoid is activated electrically by a control switch in the helicopter, electric cables being provided to link the solenoid to the control switch and power pply- I claim:

1. Apparatus for filling and emptying a container having a lower part, comprising a valve mounted in said lower part of such a container, said valve having a movable valve member, latch means cooperable with the movable valve member to hold said movable valve member in a closed position, opening means to allow an opening force to be applied to said movable valve member to open said valve, and closing means to allow a closing force to be applied to said movable valve member to close said valve, the construction and arrangement being such that in use, upon the container being at least partially immersed in a fluid to a suitable depth with said valve open, fluid will enterthe container through said valve and said valve will be closed by said closing force on operation of said closing means, and said valve will be opened to permit discharge of the container contents, by said opening force on operation of said opening means.

2. A container having a valve mounted in a lower part thereof, said valve having a movable valve member, latch means cooperable with the movable valve member to hold said movable valve member in a closed position, opening means to allow an opening force to be applied to said movable valve member to open said valve, and closing means to allow a closing force to be applied to said movable member to close said valve, the construction and arrangement being such that, in use, upon the container being at least partially immersed in a fluid to a suitable depth with said valve open, fluid will enter the container through said valve, and said valve will be closed by said closing force on operation of said closing means, and said valve will be opened, to

permit'discharge of the container contents, by said opening force on operation of said opening means.

3. The container as claimed in claim 2 wherein said opening means comprises a support attached to said movable valve member and a movable latch means engageable with said support, the construction and arrangement being such that on said movable latch means disengaging said support, an opening force is allowed to be applied to said movable valve member to open said valve.

4. The container as claimed in claim 2 wherein said opening force is gravity.

5. The container as claimed in claim 2 wherein said closing means comprises a float attached to said movable valve member, the construction and arrangement being such that a closing force is applied to said movable valve member when fluid enters said container and at least partially immerses said float and causes said float to be raised.

6. The container as claimed in claim 2 wherein a support attached to said movable valve member engages a latch means when said valve is closed by said closing force, the construction and arrangement being such that said latch means holds such movable valve member in the closed position on said valve being closed by said closing force and on said latch means engaging said support.

7. The container as claimed in claim 6 wherein said latch means and said movable latch means comprise a tripping mechanism, arranged so that said movable valve member in the closed position by said tripping mechanism being engaged with a support attached to said movable valve member, and that on said tripping mechanism being operated, said support is disengaged therefrom and an opening force is allowed to be applied to said movable valve member to open said valve.

' such that said movable valve member is held in the open position by said further tripping mechanism being engaged with a support attached to said movable valve I member and that on said further tripping mechanism being operated said support is disengaged therefrom and a closing force is allowed to be applied to said movable member to close said valve.

10. The container as claimed in claim 9 wherein said latch means adapted to hold said movable valve member inthe open position comprises said tripping mechanism, the construction and arrangement being such that said movable valve'member is held in the open position, by said tripping mechanism being engaged with said support attached to said movable valve member and that on said tripping mechanism being operated, said support is disengaged therefrom and a closing force is allowed to be applied to said movable valve member to close said valve.

11. The container as claimed in claim 10 wherein said valve is on the lower part of said container, the construction and arrangement being such that said valve is closed by said movable valve member being raised and said valve is opened by said movable valve member being lowered.

12. The container as claimed in claim 6 wherein said support is a shaft fixed to and extending up from said movable valve member, said shaft having a recess provided therein which is adapted to be engageable with said latch means.

13. The container as claimed in claim 7 wherein said latch means comprises one or more latch members pivotally attached to said container, or to a support attached thereto, one end of each of said latch members having a bearing face provided thereon adapted to engagea bearing surface on said recess and the other end of each of said latch members having a control attached thereto adapted to move said latch members, the construction and arrangement being such that said bearing face engages said bearing surface to hold said movable valve member, and on said bearing face being moved, said bearing face disengages said bearing surface and releases said movable valve member to allow an opening force or a closing force to be applied thereto. I

14. The container as claimed in claim 13 wherein each of said bearing faces is adapted to engage either one or two of said bearing surfaces, the construction and arrangement being such that said bearing face engages one of said bearing surfacesto hold said valve open and said bearing face engages the other of said bearing surfaces to hold said valve closed.

15. The container as claimed in claim 13 wherein there are two of said latch members.

16. The container as claimed in claim 13 wherein said recess has an angled surface leading to said bearing surface, the construction and arrangement being such that on said movable .valve member closing said valve, said bearing faces are moved relative to said recess and are guided by said angled surface onto said bearing surface such that said bearing face engages said bearing surface when said valve is closed and such that said valve is held closed by such engagement.

17. The container as claimed in claim 2 wherein said container is adapted to be supported from above,

18..The container as claimed in claim 2 wherein said container is adapted to be supported by and transported by ahoverableaircraft, such as a helicopter.

19. The container as claimed in claim 7 wherein said tripping mechanism is operated by a control means attached to a hoverable aircraft, such as a helicopter.

20. The container as claimed in claim 5 wherein a plurality of valves are mounted in said lower part thereof, said valves having a movable valve member, hinge means to hinge said movable valve member and stop means to limit movement of said movable valve member, the construction and arrangement being such that, in use, on the container being immersed in a fluid to a suitable depth, said valve will be opened by pressure from said fluid, said fluid will enter said container, and said valve will be closed by said fluid when the container is raised from said fluid.

21. The container as claimed in claim 2 wherein said container is provided with a deflector todeflect fluid being discharged from said container into a more concentrated flow, said deflector comprising a short tube placed around said valve.

22. The container as claimed in claim 19 wherein said control means comprises a cable, a pivotally mounted operating member to engage said cable, tension means to apply a rotational force to said operating member to maintain engagement with and apply tension to said cable, the construction and arrangement being such that in use, rotation of the operating member in the direction of said force applied by said tension means, the cable is taken up to operate said, and should a force greater than and in a direction opposite to the rotational forceapplied by said tension means by applied, said operating member will move in the direction of said greater force and disengage said cable.

Claims

1. Apparatus for filling and emptying a container having a lower part, comprising a valve mounted in said lower part of such a container, said valve having a movable valve member, latch means cooperable with the movable valve member to hold said movable valve member in a closed position, opening means to allow an opening force to be applied to said movable valve member to open said valve, and closing means to allow a closing force to be applied to said movable valve member to close said valve, the construction and arrangement being such that in use, upon the container being at least partially immersed in a fluid to a suitable depth with said valve open, fluid will enter the container through said valve and said valve will be closed by said closing force on operation of said closing means, and said valve will be opened to permit discharge of the container contents, by said opening force on operation of said opening means.

2. A container having a valve mounted in a lower part thereof, said valve having a movable valve member, latch means cooperable with the movable valve member to hold said movable valve member in a closed position, opening means to allow an opening force to be applied to said movable valve member to open said valve, and closing means to allow a closing force to be applied to said movable member to close said valve, the construction and arrangement being such that, in use, upon the container being at least partially immersed in a fluiD to a suitable depth with said valve open, fluid will enter the container through said valve, and said valve will be closed by said closing force on operation of said closing means, and said valve will be opened, to permit discharge of the container contents, by said opening force on operation of said opening means.

4. The container as claimed in claim 2 wherein said opening force is gravity.

8. The container as claimed in claim 6 wherein said container has latch means adapted to hold said movable valve member in the open position.

9. The container as claimed in claim 8 wherein said latch means adapted to hold said movable valve member in the open position comprises a further tripping mechanism, the construction and arrangement being such that said movable valve member is held in the open position by said further tripping mechanism being engaged with a support attached to said movable valve member and that on said further tripping mechanism being operated said support is disengaged therefrom and a closing force is allowed to be applied to said movable member to close said valve.

10. The container as claimed in claim 9 wherein said latch means adapted to hold said movable valve member in the open position comprises said tripping mechanism, the construction and arrangement being such that said movable valve member is held in the open position, by said tripping mechanism being engaged with said support attached to said movable valve member and that on said tripping mechanism being operated, said support is disengaged therefrom and a closing force is allowed to be applied to said movable valve member to close said valve.

13. The container as claimed in claim 7 wherein said latch means comprises one or more latch members pivotally attached to said container, or to a support attached thereto, one end of each of said latch members having a bearing face provided thereon adapted to engage a bearing surface on saiD recess and the other end of each of said latch members having a control attached thereto adapted to move said latch members, the construction and arrangement being such that said bearing face engages said bearing surface to hold said movable valve member, and on said bearing face being moved, said bearing face disengages said bearing surface and releases said movable valve member to allow an opening force or a closing force to be applied thereto.

14. The container as claimed in claim 13 wherein each of said bearing faces is adapted to engage either one or two of said bearing surfaces, the construction and arrangement being such that said bearing face engages one of said bearing surfaces to hold said valve open and said bearing face engages the other of said bearing surfaces to hold said valve closed.

16. The container as claimed in claim 13 wherein said recess has an angled surface leading to said bearing surface, the construction and arrangement being such that on said movable valve member closing said valve, said bearing faces are moved relative to said recess and are guided by said angled surface onto said bearing surface such that said bearing face engages said bearing surface when said valve is closed and such that said valve is held closed by such engagement.

17. The container as claimed in claim 2 wherein said container is adapted to be supported from above.

18. The container as claimed in claim 2 wherein said container is adapted to be supported by and transported by a hoverable aircraft, such as a helicopter.

21. The container as claimed in claim 2 wherein said container is provided with a deflector to deflect fluid being discharged from said container into a more concentrated flow, said deflector comprising a short tube placed around said valve.

22. The container as claimed in claim 19 wherein said control means comprises a cable, a pivotally mounted operating member to engage said cable, tension means to apply a rotational force to said operating member to maintain engagement with and apply tension to said cable, the construction and arrangement being such that in use, rotation of the operating member in the direction of said force applied by said tension means, the cable is taken up to operate said, and should a force greater than and in a direction opposite to the rotational force applied by said tension means by applied, said operating member will move in the direction of said greater force and disengage said cable.