GB2207219A

GB2207219A - Valve drive mechanism

Info

Publication number: GB2207219A
Application number: GB08717393A
Authority: GB
Inventors: Hans Stam
Original assignee: Fortress Interlocks Ltd
Current assignee: Fortress Interlocks Ltd
Priority date: 1987-07-23
Filing date: 1987-07-23
Publication date: 1989-01-25
Anticipated expiration: 2007-07-23
Also published as: GB2207219B; GB8717393D0

Abstract

There is mounted on a valve a drive mechanism which includes a lock mechanism 19, a key 34 for the lock mechanism and a one-way clutch 29 for impeding turning of the valve in one direction whilst permitting turning of the valve in the opposite direction, when the key is present. <IMAGE>

Description

Title:Flow-control device and drive mechanism therefore" Description of Invention According to the first aspect of the present invention, there is provided a flow-control device comprising a body, flow-control means arranged for turning relative to the body, a handle for transmitting force from a user to the flow-control means for turning same relative to the body in a forward direction and direction-control means for impeding turning of the flowcontrol means in the reverse direction without impeding turning in the forward direction.

According to a second aspect of the invention, there is provided a drive mechanism for a flow-control device, the drive mechanism comprising a housing, a handle mounted in or mountable in the housing for rotation relative thereto, an output element which is formed on or associated with the handle for transmitting torque from the handle to the flow-control device and direction-control means for impeding turning of the output element relative to the housing in one direction without impeding turning in the opposite direction.

The flow-control means may be constructed and arranged in a known manner for controlling the flow of matter or of energy. For example, the flow-control means may be a valve or an electrical switch. The flow-control means is preferably contained inside the body of the device.

The handle may be demountable from the remainder of the device or from the remainder of the drive mechanism, as the case may be.

Each of a device in accordance with the first aspect of the invention and a drive mechanism in accordance with the second aspect of the invention preferably includes locking means for releasobly locking the flow-control means in a predetermined position or in a selected one of a plurality of alternative positions relative to the body. The locking means may be of a known form, for example a tumbler lock mechanism. The locking means may be arranged to act between the handle and the housing of the mechanism or the body of the device, as the case may be. Furthermore, the locking means may be demountable from the housing or the body, when in a releasing condition.

Alternatively, in the case of a device in accordance with the first aspect of the invention, the locking means may be arranged to act between the body of the device and the flow-control means or an element constrained to turn with the flow-control means. Similarly, in the case of a mechanism in accordance with the second aspect of the invention, the locking means may be arranged to act between the housing of the mechanism and the output element.

In a case where the handle is demountoble, the handle may be adapted to serve as a key for setting the locking means in a releasing condition.

Alternatively, a key which is separate from the handle may be provided for setting the locking means in a releasing condition.

An example of a valve incorporating a drive mechanism in accordance with the second aspect of the invention will now be described, with reference to the accompanying drawings, wherein: FIGURE I shows a side view of the valve and drive mechanism, certain parts being broken away to reveal internal components, FIGURE 2 is a plan view showing the drive mechanism without a key, and FIGURE 3 is a cross-section, on an enlarged scale, on the line 111-Ill of Figure 1.

The flow-control device illustrated in the accompanying drawings is suitable for controlling the flow of a fluid, either a gas or a liquid, between at least three ports defined by respective limbs 11, 12 and 13 of a body 14 of the device. The device may be settable in any selected one of a first condition, in which all of the ports are closed, a second condition in which there is communication between the ports defined by the limbs II and 12 respectively, with the third port being closed, and a third condition in which communication is provided between the ports defined by the limbs 12 and 13, with the port defined by the limb 11 being closed.

The device comprises flow-control means which is contained inside and is arranged for turning relative to the body 10. In the example illustrated, the flow-control means is a valve member 14 defining at least one passageway which can be brought into communication with ports defined by the body 10. The valve member can be rotated an unlimited number of times relative to the body 10. When rotated, the valve member passes successively through respective positions corresponding to each of the conditions of the device. Turning through an angle of 900 may be necessary to change the condition of the device from the second condition to the third condition.

The arrangement may be such that the device remains in the first, closed, condition throughout a substantial range of angular positions of the valve member 14, for example through a range of 1800.

The body 10 includes a housing 15 which is of generally cylindrical form and defines an axis 16 which is perpendicular to an axis defined by opposite limbs li and 13. The housing is typically co-axial with the limb 12. The housing may be releasably secured on the remainder of the body 10, for example by means of a grub screw 17. If demounting of the housing from the remainder of the body is unnecessary, the grub screw may be substituted by some other form of pin. As shown in Figure I, a lower end portion of the housing 15 receives with a sliding fit either an upper portion of the remainder of the body or a bush 18 incorporated in the body. The bush may be screwed onto a spigot of the body. Furthermore, the housing 15 may be screwed on to the bush 18 or equivalent part of the body.

A lock mechanism 19 is mounted in an upper portion of the housing 15.

In the example illustrated, the lock mechanism comprises a hollow tumbler housing 20 and a core 21 mounted in the tumbler housing for rotation relative thereto about the axis 16. The lock mechanism niso includes tumblers 22 for restraining rotation of the core relative to the tumbler housing, in the absence of the proper key 32. Turning of the tumbler housing 20 relative to the housing 15 is prevented by a transverse pin 24 driven into aligned holes in the housings. It will be understood that the lock mechanism may have various forms and may be a known lock mechanism.

There is also disposed inside the housing 15 an output element 25 capable of transmitting torque from the lock core 21 to the valve member 14.

In the example illustrated, the lock core has at an end which faces towards the valve member 14 a non-circular spigot 26, not shown in Figure 3, which is received in a complementary socket defined by the output element 25. A similar socket defined by the output element and facing towards the valve member 14 receives a circular end portion of a spindle 27 of the valve member which is pinned to the output element.

The output element 25 is spaced radially inwardly from the internal surface of the housing 15 by an annular gap 28. In this gap, there is disposed direction-control means for controlling the direction of rotation of the output element and other rotatable parts of the device. The direction-control means has the form of a one-way clutch which acts to transmit torque from the housing 15 to the output element 25 in one rotational direction but is incapable of transmitting any substantial torque from the housing to the output element in the opposite rotational direction. The clutch includes a number of rollers 29 which are specked apart about the axis 16 and which lie partly in the gap 28 and partly in respective recesses 30 defined by the housing 15.With each roller, there is associated a biasing spring 31 which urges the corresponding roller out of its recess along a ramp in a direction around the axis 16.

The device further comprises a removable handle 32 which is adapted to serve as a key for the lock mechanism 19. The handle includes a driving portion 33 which, when the handle is applied to the lock mechanism, is inserted into a recess defined by the tumbler housing 20, and a hand grip 34 which remains outside the tumbler housing. The driving portion 33 is adapted to engage the tumblers 22 and move each tumbler into a respective releasing position, thereby freeing the core 21 for turning relative to the tumbler housing 20 and the housing 15. The driving portion 33 is also adapted to transmit torque from a user to the core 21. In the example illustrated, the driving portion includes a tongue which enters a transverse slot 35 defined by the core 21.

Retaining means is provided for retaining the driving portion 33 of the handle in the tumbler housing 20 except when the handle is in a predetermined rotational position relative to the housing 15. The retaining means may be of known form. For example, the retaining means may comprise a hook which is pivotally mounted in the core 21 and which is moved by the tongue 35 to engage in an opening defined by the driving portion 33, the tumbler housing 20 being formed to maintain the hook in an operative position when the handle 32 is out of the predetermined position relative to the housing 15. In an alternative arrangement, the driving portion 33 includes a radially projecting lug which can pass through a notch in a flange defined by the tumbler housing 20 and which engages underneath the flange when the handle 32 is turned relative to the housing 15.The retaining means may be arranged to permit withdrawal of the handle 32 in more than one rotational position.

When the handle 32 is absent from the remainder of the device, tuming of the valve member 14 and core 21 relative to the housing 15 is prevented by the tumblers 22. The arrangement may be such that the tumblers can occupy respective locking positions only when the device is in the first, fully closed, condition. If the retaining means is arranged to permit removal of the handle only when the device is in this condition, then the presence of the handle at a remote position is indicative of the closed condition of the device. When the handle 32 has been applied to the lock mechanism 19, the core 21 is released for turning relative to the housing 15 and the handle is able to transmit torque from the user to the core. If torque is exerted in one direction, it is transmitted by the rollers 29 to the housing 15, which is a fixed part of the body 10.Accordingly, there is no turning of the valve member 14 relative to that body. If torque is exerted in the opposite direction, the core 21, output element 25 and valve member 14 turn relative to the body 10 so that the second condition of the device can be established. If the valve member is turned further, the third condition of the device can be established.

However, reverse movement of the valve member to return the device directly to the first condition from the second condition, without passing through the third condition, is prevented. On each occasion when the condition of the device is changed, the several alternative conditions must be established in the same sequence.

Whilst we have described and illustrated a lock mechanism which is an integral part of the device and which is disposed in a housing of the device, it will be understood that there may be used n place of the integral lock mechanism a separable lock, for example a padlock, arranged to act between a handle of the device and a body of the device. In this case, the handle would not be required to serve also as a key for the lock mechanism and would not necessarily be demountable. In a case where the handle is not demountable, the output element may be an integral part of the handle.

The housing 15, lock mechanism 19, output element 25, rollers 29, springs 31 and handle 32 may be provided at a pre-assembled unit for combination with an existing valve to control the direction of rotation of the valve member of that valve. The bush 18 may be provided with that unit to facilitate mounting of the unit on the valve. It will be noted that the unit defines, at an end thereof remote from the handle 32, a wider socket defined by the housing 15 for receiving a portion of a body of the valve, or the bush 18 mounted thereon, and that the output element 25 defines a smaller socket which is an extension of the larger socket and which is adapted to receive an end portion of a spindle of the valve.

It will be understood that the invention may be applied to a valve having four or more ports. The valve may be incorporated in a system for the transmission of hydraulic power or in process plant. Furthermore, the invention may be applied to an electrical switch having a body corresponding to the body 10 described herein and a spindle or other rotatable input element corresponding to the spindle 27.

The features disclosed in the foregoing description, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

CLAIMS:

I. A flow-control device comprising a body, flow-control means arranged for turning relative to the body, a handle for transmitting force from a user to the flow-control means for. turning same relative to the body in a forward direction and direction-control means for impeding turning of the flow control means in a reverse direction without impeding turning in the forward direction.
2. A device according to Claim I wherein the handle is demountable.
3. A device according to Claim I or Claim 2 further comprising locking means for releasably locking the flow-control means in a predetermined position or in a selected one of a plurality of alternative positions relative to the body.
4. A device according to Claim 3, as appendant to Claim 2, wherein the handle serves as a key for releasing the lock mechanism.
5. A device according to Claim 4 comprising.retoining means for retaining the handle in assembled relation with the body, except when the handle is in a predetermined rotational position relative to the body or is in one of a plurality of alternative rotational positions relative to the body.
6. A device according to Claim 3 wherein the locking means is demountable from the body, when in a released condition.
7. A drive mechanism for a flow-control device, the drive mechanism comprising a housing, a handle mounted in or mountable in the housing for rotation relative thereto, an output element which is formed on or is associated with the handle for transmission of torque from the handle to the flow-control device and direction-control means for impeding turning of the output element relative to the housing in one direction without impeding turning in the opposite direction.
8. A mechanism according to Claim 7 wherein the handle protrudes from the housing at one end of the mechanism and wherein the housing defines at an opposite end of the mechanism a socket for receiving a part of the flowcontrol device.
9. A mechanism according to Claim 8 wherein the output element defines a socket for receiving an end portion of a spindle of the device and wherein the socket defined by the output element is an extension of the socket defined by the housing.
10. A mechanism according to any one of Claims 7 to 9 wherein the handle is a key for the lock mechanism and there is provided means for retaining the key in its operative position with respect to the lock mechanism, except when the key is in a predetermined rotational position relative to the housing or is in one a plurality of alternative rotational positions.
II. A flow-control device substantially as herein described with reference to the accompanying drawing.
12. Any novel feature or novel combination of features disclosed herein or in the accompanying drawing.