GB2258920A

GB2258920A - Valve actuating apparatus dependent on liquid level

Info

Publication number: GB2258920A
Application number: GB9117835A
Authority: GB
Inventors: Lawrence Burns
Original assignee: KERAFLO Ltd
Current assignee: KERAFLO Ltd
Priority date: 1991-08-17
Filing date: 1991-08-17
Publication date: 1993-02-24
Anticipated expiration: 2011-08-17
Also published as: GB9117835D0; GB2258920B

Abstract

A valve-actuating apparatus includes an actuator 6 tiltable in one sense by a float 21 which, by way of a vertical tube 20 and as a liquid level approaches an upper position, turns the actuator 6 anti-clockwise until a ball 9 in a tube 7 of the actuator 6 causes the actuator 6 to tilt to one extreme end position to close a liquid supply valve. The actuator 6 is tiltable in the opposite sense by a weight 15 which is substantially weightless when fully submerged in the liquid. As the liquid level approaches a lower position L, the weight 15 pulls a cord or chain 14 to tilt the actuator 6 until the ball 9 causes the actuator 6 to tilt to an opposite extreme position to open the valve. <IMAGE>

Description

ACTUATING APPARATUS According to one aspect of the present invention, there is provided actuating apparatus dependent upon fluid level, comprising an actuator, a float device arranged to respond to said fluid level rising to an upper position by operating said actuator in one sense, and a weight device arranged to respond to said fluid level falling to a lower position by operating said actuator in the opposite sense, the float device and the weight device having substantially no direct influence one upon the other.

This arrangement has the advantage that each of the float device and the weight device carries out its own actuator-operating function without substantially interfering with the actuator-operatinJ function of the other device. Thus, one device can be changed or adjusted, particularly as to the height of the upper position, or the lower position, as the case may be, independently of the other device.

The weight device is preferably sufficiently heavy not to float in the fluid, advantageously substantially weightless in the fluid when fully submerged therein, desirably slightly heavier than weightless.

According to a second aspect of the present invention, there is provided actuating apparatus dependent upon fluid level, comprising an actuator, a float device arranged to respond to said fluid level rising to an upper position by operating said actuator in one sense, and a weight device arranged to respond to said fluid level falling to a lower position by operating said actuator in the opposite sense, at least one of the float device and the weight device being adjustably displaceable relative to the other.

This arrangement has the advantage that at least one of the actuator-operating positions of the fluid level can be simply adjusted relative to the other.

According to a third aspect of the present invention, there is provided actuating apparatus dependent upon fluid level, comprising an actuator, and an actuator-operating device arranged to respond to said fluid level moving to a pre-determined position by operating said actuator in one sense, the arrangement being such that, immediately upon said device having operated said actuator in said one sense, said device substantially loses its influence upon said actuator.

This arrangement has the advantage that, once the device has performed its actuator-operating function, for which it necessarily has an influence upon the actuator, the actuator is substantially free to be subjected solely to other operating influence According to a fourth aspect of the present invention, there is provided actuating apparatus dependent upon fluid level, comprising an actuator, and a weight device arranged to respond to said fluid level falling to a lower position by operating said actuator in one sense, the arrangement being such that the weight device is substantially weightless in the fluid except when the fluid level is in the region of said lower position.

Advantageously, the weight device is slightly heavier than weightless when fully submerged in the fluid.

According to a fifth aspect of the present invention, there is provided actuating apparatus dependent upon fluid level, comprising an actuator, and a weight device arranged to respond to said fluid level falling to a lower position by operating said actuator in one sense, the density of the weight device being substantially equal to the density of the fluid.

Advantageously, the density of the weight device is slightly greater than the density of the fluid.

These arrangements have the advantage that the weight effect of the weight device upon the actuator occurs as the lower position is approached, so producing operation of the actuator.

In order that the invention may be clearly understood and readily carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a diagrammatic front elevation of a valve-actuating apparatus, with a liquid level in an upper position, and Figure 2 is a diagrammatic partly-sectional front elevation of the apparatus, but with the liquid level in a lower position.

Referring to the drawings, there is seen a valve device 1 which has a horizontal axis and which is advantageously of the character disclosed in European Patent Application Publication 0144117. Mounted in the device 1 so as to the turnable about the horizontal axis of the device 1 is a radial arm (not shown) which is fixed to a turning valve disc (not shown) in the device 1. The device 1 includes a co-axial fixed spigot 4 upon which is freely turnably mounted a radial plate 5 of an actuator 6. The actuator 6 also includes a tube 7 closed at both ends by caps 8 and containing a heavy ball 9 and damping liquid 10. The tube 7 extends perpendicularly to the horizontal valve axis and is fixed along the radially outer edge of the plate 5.Between the spigot 4 and that radially outer edge the plate 5 is formed with an arcuate slot 11 co-axial with the device 1 and receiving a horizontal pin 12 fixed to the radially outer end zone of the abovementioned radial arm and whereby turning of the actuator 6 about the horizontal axis of the valve device 1 results, after an angular delay in each sense, in turning of that radial arm and thus opening and closing of the device 1.

In the condition of the actuator 6 shown in Figure 1, the valve device 1 is fully closed, whilst in the condition of the actuator 6 shown in Figure 2, the device 1 is fully open. Anchored in an eye 13 in the radially outermost portion of the plate 5 is an elongate member 14, advantageously in the form of a cord or chain. Attached to the lower end of the member 14 is a weight 15. The valve device 1 is carried by a bracket 16 to which is fixel i vertical guide sleeve 17 below the actuator 6. The sleeve 17 is formed with vertical slotting 18 through which extends a horizontal guide pin 19 of a vertical tube 20 having closed upper and lower ends. Encircling the tube 20 are a float 21 and upper and lower collars 22 fixed to the float. The collars 22 and thus the float 21 are releasably fixed to the tube 20 by means of respective set screws 23.The member 14 extends through a vertical slot 24 through the float 21.

The actuating apparatus is contained within a water tank 25 within which the water level may vary between the upper position U in Figure 1 and the lower position L in Figure 2. The weight 15 is substantially weightless when completely submerged in water, advantageously having a very slight weight in water to maintain the member 14 extended. Thus, its density is very slightly greater than the density of the water.

The method of operation of the apparatus is as follows. With the apparatus in the condition shown in Figure 1 and with the water level falling from the position U owing to consumption of water from the tank 25, the float assembly 19 to 24 falls until the pin 19 abuts the lower end of the slotting 18 and then remains held in that position by the sleeve 17. The actuator 6 remains in the condition shown in Figure 1, particularly because of the ball 9 being at the left-hand end of the tube 7. As the liquid level continues to fall, it ultimately begins to uncover more and more of the upper part of the weight 15, so that the weight 15 applies an increasing pull to the member 14, until the pull on the member 14 is sufficient to turn the actuator 6 clockwise.As the actuator 6 approaches the horizontal, the liquid 10 begins to flow from the left-hand end of the actuater 6 to the right-hand end thereof and, as the actuator 6 passes through the horizontal, the ball 9 rolls from the left-hand end thereof to the right-hand end thereof, its impact against the right-hand cap 8 being damped by the liquid 10. Owing to the weight transfer in the actuator 6 from one side to the other of the valve axis, and after an angular delay provided by the slot 11, the plate 5 strikes the pin 12 and displaces it clockwise to open the valve. The apparatus therefore attains the condition shown in Figure 2, in which the weight 15 has been lowered from an uppermost position shown in Figure 1 to a lowermost position, and water begins to flow from the valve 1 into the tank 25. As the water level rises, the actuator 6 remains in the condition shown in Figure 2. As the water level rises around the float 21, it begins to lift the float assembly 19 to 14 upwards until the closed upper end of the tube 20 comes to bear on the plate 5 and then continued rise in the water level turns the actuator 6 anticlockwise until the ball 9 rolls from the right-hand end of the tube 7 to the left-hand end thereof to bring the actuator 6 back into the condition shown in Figure 1, which has the effect of closing the device 1 and of lifting the weight 15 into its uppermost position.

The apparatus described with reference to the drawings has several advantages. The position U, which is substantially the highest position of the water in the tank 25, is infinitely adjustable over a considerable height range by simply adjusting the position of the float 21 along the tube 20 by means of the set screws 23. The only significant limitation to this height range is the practically feasible maximum length of the tube 20. Similarly, the position L is again infinitely adjustable over a considerable height range, this time by simply altering the length of the member 14. The only significant limitation to this height range is the practically feasible maximum length of the member 14. Another advantage is that the positions L and U can be set by the apparatus independently of each other.The further advantage is that the float device 19 to 24 and the weight device 14 and 15 function independently of each other, in other words neither has any direct influence upon the operation of the other, so that adjustment or change of one does not affect the other. In this respect, it should be noted that, once the float device 19 to 24 has caused an anti-clockwise tilting of the actuator 6, the actuator 6 is no longer subjected to any influence from the float device. Similarly, for all of the time that the weight 15 is substantially weightless in the water, it has substantially no influence upon the actuator 6. Moreover, the arrangement whereby there is the sudden weight transfer from one side of the axis of turning of the actuator 6 to the other side of the actuator axis produces strong positive opening and closing of the valve device, thus avoiding wear owing to high-pressure low-rate flows through the valve device. Furthermore, the delay arrangement whereby opening and closing of the valve device take place only when the tank is virtually empty and virtually full, respectively, avoids the wear which would occur for the same water consumption if the tank were instead to be continually refilled when only partially empty.

Claims

1. Actuating apparatus dependent upon fluid level, comprising an actuator, a float device arranged to respond to said fluid level rising to an upper position by operating said actuator in one sense, and a weight device arranged to respond to said fluid level falling to a lower position by operating said actuator in the opposite sense, the float device and the weight device having substantially no direct influence one upon the other.

2. Apparatus according to claim 1, wherein, immediately upon each of said float device and said weight device having operated the actuator in the relevant sense, said device substantially loses its influence upon said actuator.

3. Apparatus according to claim 2, wherein the weight device is substantially weightless in the fluid except when the fluid level is in the region of said lower position.

4. Apparatus according to claim 3, wherein the weight device is slightly heavier than weightless when fully submerged in the fluid.

5. Apparatus according to claim 2, wherein the density of the weight device is substantially equal to the density of the fluid.

6. Apparatus according to claim 5, wherein the density of the weight device is slightly greater than the density of the fluid.

7. Apparatus according to any preceding claim, wherein at least one of the float device and the weight device is adjustably displaceable relative to the other.

8. Apparatus according to any preceding claim, wherein the weight device is connected to the actuator by way of a readily flexible, elongate member by way of which said weight device pulls said actuator in said opposite sense.

9. Apparatus according to claims 7 and 8, wherein the effective length of said elongate member between said weight device and said actuator is adjustable.

10. Apparatus according to any preceding claim, wherein said float device operates said actuator by way of a relatively rigid, elongate member by way of which said float device pushes said actuator in said one sense.

11. Apparatus according to claim 10 as appended to claim 2, wherein said relatively rigid, elongate member acts on said float device in only the region of the beginning of movement of said actuator in said one sense.

12. Apparatus according to claim 7 and claim 10 or 11, wherein the effective length of said relatively rigid, elongate member between said actuator and said float device is adjustable.

13. Apparatus according to claim 9 or 12, wherein the or each said effective length is infinitely adjustable.

14. Apparatus according to any preceding claim, wherein said one sense and said opposite sense are of turning about an axis.

15. Apparatus according to claim 14, wherein said axis is substantially horizontal and said actuator comprises an elongate guide tiltable about said axis which is spaced inwardly from the ends of the guide, and a mass guided by said guide for limited movement along said guide to-and-fro past said axis.

16. Apparatus according to claim 15, wherein said mass comprises a circular, rolling member.

17. Apparatus according to claim 15 or 16, wherein said guide comprises a tube closed at both ends and containing a damping liquid.

18. Apparatus according to any preceding claim and further comprising means limiting the range of movement of said actuator in said one sense and said opposite sense.

19. Apparatus according to any preceding claim, and further comprising means limiting to within the region of said upper position the extent to which the float device can fall with the fluid level.

20. Actuating apparatus dependent upon fluid level, comprising an actuator, a float device arranged to respond to said fluid level rising to an upper position by operating said actuator in one sense, and a weight device arranged to respond to said fluid level falling to a lower position by operating said actuator in the opposite sense, at least one of the float device and the weight device being adjustably displaceable relative to the other.

21. Apparatus according to claim 20, wherein the weight device is connected to the actuator by way of a readily flexible, elongate member by way of which said weight device pulls said actuator in said opposite sense.

22. Apparatus according to claim 21, wherein the effective length of said elongate member between said weight device and said actuator is adjustable.

23. Apparatus according to claim 20, 21, or 22, wherein said float device operates said actuator by way of a relatively rigid, elongate member by way of which said float device pushes said actuator in said one sense.

24. Apparatus according to claim 23, wherein said relatively rigid, elongate member acts on said float device in only the region of the beginning of movement of said actuator in said one sense.

25. Apparatus according to claim 23 or 24, wherein the effective length of said relatively rigid, elongate member between said actuator and said float device is adjustable.

26. Apparatus according to claim 22 or 25, wherein the or each said effective length is infinitely adjustable.

27. Actuating apparatus dependent upon fluid level, comprising an actuator, and an actuator-operating device arranged to respond to said fluid level moving to a predetermined position by operating said actuator in one sense, the arrangement being such that, immediately upon said device having operated said actuator in said one sense, said device substantially loses its influence upon said actuator.

28. Apparatus according to claim 27, wherein the device is a weight device which is substantially weightless in the fluid except when the fluid level is in the region of said position.

29. Apparatus according to claim 28, wherein the weight device is slightly heavier than weightless when fully submerged in the fluid.

30. Apparatus according to claim 27, wherein the device is a weight device whereof the density is substantially equal to the density of the fluid.

31. Apparatus according to claim 30, wherein the density of the weight device is slightly greater than the density of the fluid.

32. Apparatus according to claim 27, wherein the device is a float device which operates said actuator by way of a relatively rigid, elongate member by way of which said float device pushes said actuator in said one sense, and wherein said relatively rigid, elongate member acts on said float device in only the region of the beginning of movement of said actuator in said one sense.

33. Actuating apparatus dependent upon fluid level, comprising an actuator, and a weight device arranged to respond to said fluid level falling to a lower position by operating said actuator in one sense, the arrangement being such that the weight device is substantially weightless in the fluid except when the fluid level is in the region of said lower position.

34. Apparatus according to claim 33, wherein the weight device is slightly heavier than weightless when fully submerged in the fluid.

35. Actuating apparatus dependent upon fluid level, comprising an actuator, and a weight device arranged to respond to said fluid level falling to a lower position by operating said actuator in one sense, the density of the weight device being substantially equal to the density of the fluid.

36. Apparatus according to claim 35, wherein the density of the weight device is slightly greater than the density of the fluid.

37. Actuating apparatus dependent upon fluid level, substantially as hereinbefore described with reference to the accompanying drawings.