GB2192971A - Gas taps - Google Patents

Abstract

In a gas valve assembly comprising a normally-closed valve 14 linked for movement with a rotary valve 20 by means of a single operating member 22, the axis of valve 14 is transverse to the axis of operating member 22 and a cam 30 is provided on member 22 for actuating valve 14. Preferably the cam has a lobe which is aligned with valve 14 only in one predetermined angular disposition of member 22, and member 22 is spring-urged to a position in which the cam is ineffective. <IMAGE>

Description

SPECIFICATION Gas taps This invention relates to gas taps of the kind comprising a first normally closed valve which is arranged to be held open by a flame sensor or by manual overide against a spring. Because this first valve does not need any intermediate positions and is either on or off, the usual construction is as a plug which is displaced axially reiative to a seat. The tap also comprises a second valve which may require to be movable to at ieast one intermediate position between off and on to vary the flow rate. For this purpose an angular movement is chosen. The two valves are in series.An angularly movable member which is also axially displaceable is used to control both valves in the ignition sequence and by suitable means such as nitings controlling the angular position in which axial movement is also possible this enables the designer to ensure that the second valve is in a suitable position when the first valve is overridden. A tap having the two valves so linked for movement of a single operating member angularly and axially is herein called "of the kind referred to".

The object of the invention is to provide an improved construction.

In accordance with the invention a valve of the kind referred to has the axis of said first valve generally transverse to the axis of movement of the operating member, and a cam is provided on the said operating member for actuating for said first valve.

The second valve may be a disc valve and the operating member may be keyed or likewise anguiarly fast with the disc but axially movable relative to the latter.

One embodiment of the invention is now more particularly described with reference to the accompanying diagrammatic drawings wherein: Figure 1 shows a tap in the off position; Figure 2 shows the tap in the ignition position; and Figure 3 shows the same in the on position.

In the drawings, the tap has an inlet 10 connected with a chamber 12 via the flame failure operated thermal magnet valve 14. The latter is opened, or held open, by a flame at the burner, and in order to provide gas for ignition before the flame is lit, the valve can be held open (over-ridden) by displacement of cam follower 16 against the return spring 18.

The second valve comprises disc 20 keyed to spindle 22 and urged against valve face 24 by spring 26. When the disc is in one angular position, no flow from the chamber 12 to the outlet (not shown) is possible: in another position low flow, and so on.

Spindle 22 carries cam 30, likewise angularly fast with the spindle. The spindle is rendered gas tight in the casing by an 0 ring 32 and carries a niting pin 34 controlling its position angularly and axially. the niting slot and pin are shown in Figs. 1A, 2A and 3A, corresponding to the positions of the parts in the main figures.

In Fig. 1, showing the parts in the off position, the pin 34 is in a relatively deep pocket 36 in the niting, preventing movement of the spindle inadvertently, and requiring a positive action to displace the pin.

Fig. 2A shows the effect of an initial purely axial displacement of the spindle 22 to take the niting pin out of the said pocket, and Fig.

2 (the main view) also shows the cam 30 having been displaced angularly, by a corresponding movement of the spindle so as to move the cam follower 16 and open the valve 14 for flow of gas from the inlet via the chamber and through the outlet to the burner.

Fig. 3 (main view) shows the axial pressure released so as to disengage the effective cam lobe from the cam follower 16, with the disc turned to an intermediate position for partial flow, and Fig. 3A shows the niting pin in that partial flow position. The recess 40 may for example provide a resting place for the pin 34 in a predetermined low flow or simmer position.

1. Valve of the kind referred to having the axis of said first valve generally transverse to the axis of movement of the operating member, and a cam provided on said operating member for actuating the said first valve.

2. A valve as claimed in Claim 1 wherein the cam is angularly fast with a control spindle and has a lobe for displacing the first valve member to an open position, which lobe is aligned with said first valve member only in one predetermined angular position of the spindle.

3. A valve as claimed in Claim 2 wherein the spindle is spring urged to a position in which the cam is ineffective.

4. A gas valve substantially as described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Gas taps This invention relates to gas taps of the kind comprising a first normally closed valve which is arranged to be held open by a flame sensor or by manual overide against a spring. Because this first valve does not need any intermediate positions and is either on or off, the usual construction is as a plug which is displaced axially reiative to a seat. The tap also comprises a second valve which may require to be movable to at ieast one intermediate position between off and on to vary the flow rate. For this purpose an angular movement is chosen. The two valves are in series.An angularly movable member which is also axially displaceable is used to control both valves in the ignition sequence and by suitable means such as nitings controlling the angular position in which axial movement is also possible this enables the designer to ensure that the second valve is in a suitable position when the first valve is overridden. A tap having the two valves so linked for movement of a single operating member angularly and axially is herein called "of the kind referred to". The object of the invention is to provide an improved construction. In accordance with the invention a valve of the kind referred to has the axis of said first valve generally transverse to the axis of movement of the operating member, and a cam is provided on the said operating member for actuating for said first valve. The second valve may be a disc valve and the operating member may be keyed or likewise anguiarly fast with the disc but axially movable relative to the latter. One embodiment of the invention is now more particularly described with reference to the accompanying diagrammatic drawings wherein: Figure 1 shows a tap in the off position; Figure 2 shows the tap in the ignition position; and Figure 3 shows the same in the on position. In the drawings, the tap has an inlet 10 connected with a chamber 12 via the flame failure operated thermal magnet valve 14. The latter is opened, or held open, by a flame at the burner, and in order to provide gas for ignition before the flame is lit, the valve can be held open (over-ridden) by displacement of cam follower 16 against the return spring 18. The second valve comprises disc 20 keyed to spindle 22 and urged against valve face 24 by spring 26. When the disc is in one angular position, no flow from the chamber 12 to the outlet (not shown) is possible: in another position low flow, and so on. Spindle 22 carries cam 30, likewise angularly fast with the spindle. The spindle is rendered gas tight in the casing by an 0 ring 32 and carries a niting pin 34 controlling its position angularly and axially. the niting slot and pin are shown in Figs. 1A, 2A and 3A, corresponding to the positions of the parts in the main figures. In Fig. 1, showing the parts in the off position, the pin 34 is in a relatively deep pocket 36 in the niting, preventing movement of the spindle inadvertently, and requiring a positive action to displace the pin. Fig. 2A shows the effect of an initial purely axial displacement of the spindle 22 to take the niting pin out of the said pocket, and Fig. 2 (the main view) also shows the cam 30 having been displaced angularly, by a corresponding movement of the spindle so as to move the cam follower 16 and open the valve 14 for flow of gas from the inlet via the chamber and through the outlet to the burner. Fig. 3 (main view) shows the axial pressure released so as to disengage the effective cam lobe from the cam follower 16, with the disc turned to an intermediate position for partial flow, and Fig. 3A shows the niting pin in that partial flow position. The recess 40 may for example provide a resting place for the pin 34 in a predetermined low flow or simmer position. CLAIMS

1. Valve of the kind referred to having the axis of said first valve generally transverse to the axis of movement of the operating member, and a cam provided on said operating member for actuating the said first valve.

2. A valve as claimed in Claim 1 wherein the cam is angularly fast with a control spindle and has a lobe for displacing the first valve member to an open position, which lobe is aligned with said first valve member only in one predetermined angular position of the spindle.

3. A valve as claimed in Claim 2 wherein the spindle is spring urged to a position in which the cam is ineffective.

4. A gas valve substantially as described with reference to the accompanying drawings.