IE44505B1 - Control device for a valve - Google Patents

Abstract

1512770 Valves APPLICATION DES GAZ 23 March 1977 [30 March 1976] 12290/77 Heading F2V The control knob 6 of a valve (not shown) is coupled to an intermediate member 12 which has a projecting rib 15 arranged to engage a fixed abutment 16 in the open and closed positions of the valve, the coupling between the knob 6 and the member 12 being such that when the rib 15 engages the abutment 16 on closing the valve, the knob 6 may be rotated further independently of the member 12. As shown the coupling comprises a ratchet and pawl. A disc 10 attached to the member 12 carries reference marks which register with a fixed reference.

Description

The present invention relates to valves or taxjs in particular of the needle valve type, and more particularly to a device for controlling the closure member of the valve.

In the needle type of valves or taps the closure member termed a needle is integral- with a screwthreaded rod the rotation of which is controlled by an actuating knob and determines the application of the needle against its seat for closing the valve or the moving away of this needle from the seat for the opening. The repeated actuation of the valve results in a wear Of the needle valve member and of its seat and this causes a progressive displacement, of the angular position of the actuating knob in the valve closing condition.Wow, in many applications it is necessary, if not essential, that the angular closing position of the actuating knob »* be predetermined and fixed and correspond effectively to the closure of the section of passage defined between the needle valve member and the seat. : Thus, for example, the replacement of plug valves by needle valves in domestic gas cooking apparatus(cookers, stoves, etc...) encounters many obstacles from the point of view of the user and the point of view of safety regu. ; lati'ons in particular because the angular closing position of the actuating knob of the needle valves changes over a period of time and that, even if this angular closing position is set by means of an abutment for example, the user is never sure that the needle valve is in fact closed in this predetermined position. Also, according to this needle valve application, it is an illusion - 2 to locate the angular closing position of the needle valve by tha coincidence of a reference carried by the actuating knob and another reference carried by the fixed support of the valve. There are twc possibilities : either the closing position of the actuating knob is not set angularly, and the coincidence of the two references which occurs when the valve is new is no longer obtained in the course of time since the two references become vore and more remote from each other as the needle valve member and the seat become 10 worn; or the closing position of the actuating knob is set angularly and the coincidence of the tvc references no longer provides the user wu-th an effective closure of the needle valve, since the latter becomes slightly open owing to the wear of tin? needle valve member and it? seat.

Thus, there is a long felt need for a device controlling needle valves, the angular position of closure of which is fixed and predetermined while ensuring the user that tha valve is effectively closed in this position.

It is only when these two conditions are satisfied that the reference to the angular position of closure cf the valve can be valid.

An object cf the present invention is to provide a control device for a valve, in particular of the needle valve type, whereby it is possible to overcome the aforementioned drawbacks and which more precisely imparts to the considered device a fixed and predetermined angular position of closure which effectively corresponds to the closure of the valve.

According to the invention, there is provided a control device for a valve., in particular of the needle valve type, comprising an actuating means mounted to be rotatable with respect to a fixed support, said device comprising : an abutment mounted on the fixed support, an intermediate rotary member disposed between the actuating means and the fixed support and provided with a bearing element one side of which bearing element is adapted to bear against one side of the abutment in the closing position of the valve, and a connecting mechanism between the actuating means and the intermediate member to render them connected to rotate together while allowing, if necessary, a continued rotation .of the actuating means independently of the intermediate member in the direction for closing the valve when said sides of the bearing element and abutment bear against each other.

According to one feature of the invention, when the control device comprises two references, one being fixed· and the other movable, respectively associated with the fixed support and the actuating means, for determining at least a reference or set position, the movable reference is carried by the intermediate member and said reference position corresponds to the position of closure of the valve.

According to another feature of the invention, the connecting mechanism is a mechanism comprising a pawl and teeth.

Further features and advantages of the invention will be apparent from . ..a ensuing description with reference to the accompanying drawings, in which : Figure l· is s?sectional and elevational view of the control device according to the invention, corresponding to the closed position of the valve and taken along line 1-1 of .Figure' 2; Figure 2 -is a sectional view taken on line 2-2 of Figure 1; j,' 4 4S0S Figure 3 ia a view similar to Figure 1, but corresponding io the maximum opening position of the valve, and Figure 4 is an exploded perspective view with a 5 part cut away of the control device according to the invention.

With reference to the Figures and in particular io Fig. 2, there is shown a control device 1 according to the invention mounted on the rod 2 of the needle valve member iO (not shown) of a valve or tap 3 of which there is shown only the end retained by an elastically yieldable washer 3a in an opening 4 of a fixed support 5.

Ths control device 1 comprises an actuating knob 6 which is connected to rctare with the rod 2, and an intermediate member 7 which is rotatably mounted between the knob 6 and the support 5. The actuating knob 6 has a cylindrical skirt 6a and a central boss 8 which projects inside the skirt and has a bore 9 adapted to receive the end of the rod 2 which is provided with a flat face. The outer surface of the skirt 6a is preferably knurled to facilitate the gripping of the knob. The intermediate member 7 comprises a disc 10 having a diameter exceeding the diameter of the skirt 6a which earri-s references 0 and F and which has a central opening 11, and a sleeve 12 whose outside diameter is less than the diameter of the opening 11. The sleeve 12 is connected to the disc 10 by three lugs 13, 14 and 15. The lugs 13 and 14 are cranked in such manner as to extend at a certain distance from the sleeve 12 and to be capable of passing over an abutment 16 which projects from the fixed support 5 through the opening 11 along the sleeve 12. On the _ E _ other hand, the third lug 15 is constituted by a longitudinal rib on the sleeve 12 adapted to cooperate with the abutment for defining the extreme positions of the control device 1 in which the references F and 0 coincide respectively with a fixed reference R carried by the fixed support 5.

The sleeve 12 is arranged to be a slight interference fit on the boss 8 and, in this position, shown in particular in Figure 2, the sleeve 12 is received in the annular space between the boss 8 and the cylindrical skirt 6a of the knob 6. In the illustrated embodiment, the sleeve 12 is shorter than the lugs 13, 14 and 15 so that the end of the body of the valve 3 can project through the opening 11 without abutting the sleeve, which results in a minimum overall size of the valve.

The actuating knob 6 is connected to rotate with the intermediate member 7 by a pawl mechanism comprising an elastically yieldable strip 17 received in a slot in the sleeve 12 and cooperating with a ratchet or teeth 18 provided on the inner face of the skirt 6a of the knob 6. The orientations pf the teeth 18 and strip 17 are arranged to ensure a positive interconnection in the direction for opening the valve, namely in the counterclockwise direction in Figures 1 and 3, but the force of application of the strip again0’'· ^he teeth 18 is sufficient to drive the intermediate member 7 in the opposite direction by means of the knob 6 so long as the member 7 is not stopped by the abutment 16.

In operation, the coincidence of the references F and R defines a reference position corresponding to the closed state of the valve which is shown in Figure 1 in which one of the sides of the lug 15 bears against one side of the abutment 16 - 5 To open the valve, the actuating knob 6 is rotated in the conventional manner in the counterclockwise direction. This ensures a positive connection between the knob 6 and the member 7 through the strip 17, whioh bears against the-bottom of one of the teeth 18, and the member 7 is consequently driven in rotation with the knob 6. Maximum opening is achieved by rotating the knob 6 to the and of its travel, that is to say, until one side of the rib 15 of the sleeve 12 bears against the opposite side of the abutment 15. Continuance of the opening movement is then prevented by the aforementioned positive connection. In this position, the reference 0 and P. coincide. To ensure the closure cf the valve, the knob S is rotated in the opposite direction and the member 7 is also driven owing to the force of application cf the strip 17 againct the teeth 18. When the rib 15 bears against the abutment 16, the member 7 is stopped in the reference position and the valve is normally closed.

However, if, owing to wear of the needle valve member and its seat, the closing travel tends to increase, the intermediate member 7 remains in the reference position whereas the knob 6 can continue to rotate until the complete closure of the valve is achieved and this is achieved while applying thereto sufficient force to cause the elastically yieldable strip 17 to move past one or more teeth 18. If will therefore be understood that notwithstanding the wear of the needle valve member and its seat, the reference position of the closure of the valve does not vary, so that it is possible ts avoid the aforementioned drawback due to the offsetting of the fixed and movable references.

It must be understood that many modifications may be made in the control device according to the invention.

Thus, the elastically yieldable strip could be carried by the knob and the lugs 13, 14 and 15 could be replaced by a ring carrying the teeth on its outer surface. The connecting mechanism including the pawl could also be carried by the end face of the sleeve 12 and the adjacent end of the knob 6 respectively. Moreover, the connection could be achieved in a manner other than by means of a pawl mechanism, In particular by means of a friction mechanism, for example Including a spring, or by any other suitable mechanism.

Furthermore, the shape and the dimensions of the intermediate member 7 are not critical and the disc 10 of the described embodiment could be for example replaced by a disc having a • diameter less than or equal to that of the knob and have on its periphery an index, whereas the references F and 0, and possibly a graduation, would be carried by the fixed support.

It is also possible to eliminate the disc and merely provide an index integral with the sleeve 12. The control device according to the invention is not limited to its utilisation with a needle valve and it could be applied to the control of any type of valve or like device in which there is a progressive displacement of a reference position of the actuating means.

Claims (11)

1. A control device for a valve, in particular of the needle valve type, comprising an actuating means mounted to be rotatable with respect to a fixed support, 5 said device comprising ; an abutment mounted on the fixed support, an intermediate rotary member disposed between the actuating means and the fixed support and provided with a bearing element one side of which bearing element is adapted to bear against one side 10 of the abutment in the closing position of the valve, and a connecting mechanism between the actuating means and the intermediate member to render them connected to rotate together while allowing, if necessary, a continued rotation of the actuating means independently of the intermediate IS member in the direction for closing the valve when said sides of the bearing element and abutment bear against each other.

2. A device according to Claim 1, comprising two references, one of which references is fixed whereas 20 the other is movable, respectively associated with the fixed support and the actuating means for determining at least one reference position, wherein the movable reference is carried by the intermediate member and said reference position corresponds to the position of 25 closure of the valve.

3. A device as claimed in Claim 1 or 2, wherein the connecting mechanism is a pawl and teeth mechanism. ’

4. A device as claimed in Claim 3, wherein . .1 4450® ί’ i the pawl bears against the teeth with sufficient force to ensure the driving of the intermediate member by the actuating means in the direction in which the pawl and the teeth are not positively interengaged.

5. 5. A device as claimed in Claim 3 or 4, wherein the teeth are carried by the actuating means and the pawl is an elastically yieldable strip carried by the intermediate member.

6. A device as claimed in Claim 5, wherein 10 the actuating means is a knob which has a skirt carrying said teeth internally and has a central boss defining a cavity for mounting it on a control rod of the closure member of the valve.

7. A device as claimed in claim 6» wherein 15 the intermediate member comprises a sleeve which is mounted to be a slight interference fit on said boss and, opfcionnally, a disc carrying a movable reference.

8. A device as claimed in claim 7, comprising a disc having a central opening whose diameter exceeds 20 the outside diameter of the sleeve and said abutment projects through said opening along said sleeve.

9. A device as claimed in Claim 8, wherein the disc is connected to the sleeve by at least two cranked lugs which allow the passage of said abutment 23 and by a longitudinal rib formed on the sleeve and forming said bearing element which bears against said abutment.

10. A device as claimed in Claim 9, wherein 30 the other side of the rib bears against the other side of the abutment to determine the maximum opening position of the valve.

11. A control device for a valve, substantially as hereinbefore described with reference to and as shown in the accompanying drawings.