GB2041510A - Improvements to gas taps for supplying burners - Google Patents

Abstract

The invention relates to gas taps for supplying burners. The gas tap comprises an electromagnetic valve 5 and thermocouple safety device 6, control means being provided for acting on the valve 8 of the electromagnetic valve 5 during lighting; these control means comprise a cocking lever 18 which is engaged by a locking member 11 and mechanical connection means between this cocking lever and the electromagnetic valve. <IMAGE>

Description

SPECIFICATION Improvements to gas taps for supplying burners The invention relates to gas taps for supplying burners having an electromagnetic valve and thermocouple safety device.

Such gas taps comprise, at the gas inlet, an electromagnetic valve whose electromagnet is connected to the circuit of a thermocouple disposed in the vicinity of the burner supplied by the tap considered.

This electromagnetic valve occupies, when its electromagnet is not excited, a closed position and, when the burner is to be lit, it is necessary to act, through appropriate control means, on the closing element of the electromagnetic valve to maintain it mechanically open, during the time required for a sufficient current to be established in the thermocoupleelectromagnet circuit.

It is known to provide taps of this type with locking means in the closed position provided by a pin or similar carried by the rotating part of the tap, and a housing carried by the nonrotating part of the tap.

Unlocking is then effected by pushing axially the rotating part towards the non-rotating part of the tap so as to disengage said pin from its housing.

It then seemed convenient, to actuate the control means holding the electromagnetic valve open, to have recourse to an additional axial push of the rotating part towards the non-rotating part of the tap.

However, the action of the user to maintain this additional axial push during the time required for current to be established in the circuit of the thermocouple was not obtained naturally in the succession of gestures leading to the lighting of the burner.

Moreover, the rotating part of the tap and its actuating knob must be able to undergo, in relation to the wall of the apparatus on which the burner is mounted, a first depression (unlocking axial push), then a second depression (axial push for maintaining the electromagnetic valve open). This requirement of disposing of two successive depressions resulted, for the tap in the closed position, in the actuating knob being situated unesthetically at a considerable distance from the wall of the apparatus considered.

The invention has precisely as an aim to remedy these disadvantages.

The invention has as an aim a tap which may be actuated, for lighting the burner, by a succession of gestures natural to the user.

The invention has also as an aim a tap whose actuating knob is situated at a minimum distance from the wall of the apparatus.

The gas tap in accordance with the invention comprises an electromagnetic valve and thermocouple safety device, control means for maintaining the electromagnetic valve open during the time required for current to be established in the thermocouple circuit and a locking means in the closed position formed by at least one pin carried by the rotating part and by at least one housing carried by the non-rotating part, and it is characterized by the fact that these control means comprise, -a cocking lever which is engaged by the locking pin when the rotating part has effected a rotational movement and is maintained pushed towards the non-rotating part and which is freed by said locking pin when the rotating part is no longer maintained pushed towards the non-rotating part, -and mechanical connection means between this cocking lever and the mobile part of the electromagnetic valve.

Preferably, these mechanical connecting means are of a type which amplifies the movements between the cocking lever and the mobile part of the electromagnetic valve.

The invention consists, apart from the arrangements which have just been discussed, of certain other arrangements which will be discussed more explicitly hereafter.

The invention will, in any case, be well understood with the help of the complement of description which follows as well as the accompanying drawing, which complement and drawing are relative to a preferred embodiment of the invention.

Figure 1 of this drawing is a schematical view of a tap constructed in accordance with the invention.

Figure 2 is a perspective view showing the essential elements of this tap.

Figures 3, 4 and 5 are partial developed views showing the relative positions of the elements illustrated in Fig. 2 in the different positions which they occupy during lighting of the burner suppied by the tap.

In Fig. 1, there is shown a gas tap for supplying a burner designated, generally, by the reference number 1.

This burner may comprise a burner head 2 fed with an air-gas mixture by a venturi tube 3, itself fed with gas by a gas injector 4.

Such a burner may comprise, in a way known per se, an electromagnetic valve 5 and a thermocouple 6 safety device.

This electromagnetic valve 5 comprises, for this purpose, an electromagnet 7 acting on a valve 8 mounted at the gas inlet 9 and which is maintained in its closed position by means of a spring 10.

This valve 8 is maintained open by the electromagnet 7 when this latter is fed by the thermocouple 6.

This thermocouple 6 is disposed in the vicinity of burner 1 and, when this burner 1 is to be lighted, it is necessary to act, through appropriate control means, on valve 8 to maintain it mechanically open during the time required for a sufficient current to be estab lished in the thermocouple 6-electromagnet 7 circuit.

Moreover, it is known to fit to taps of this type a means for locking in the closed position formed by a pin 11, carried by the rotating part 1 2 of the tap, and a housing 13, carried by the non-rotating part 14 of the tap.

The unlocking of the tap is then effected by axially pushing, for example against a spring 15, the rotating part 1 2 towards the nonrotating part 14 to disengage said pin 11 from its housing 13.

The tap comprises, furthermore, rotated by the rotating part 12, a cock-shell 1 6 cooperating with a tap body 1 7 for opening, closing and possibly adjusting, the gas flow towards gas injector 4.

The control means, for acting on the valve 8 of the electromagnetic valve 5 for maintaining it mechanically open during the time required for a sufficient current to be established in the thermocouple 6-electromagnet 7 circuit, comprise, as shown in Figs. 1 to 5, -a cocking lever 1 8 which is engaged by the locking pin 11, when the rotating part 1 2 has undergone a rotational movement and is maintained pushed towards the non-rotating part 14, and which is released by said locking pin 11 when the rotating part 1 2 is no longer maintained pushed towards the non-rotating part 14, -and mechanical connection means 1 9 between this cocking lever 18 and the valve 8 of the electromagnetic valve 5.

These mechanical connection means 1 9 are advantageously of a type which amplifies the movements between the cocking lever 18 and the valve 8 of the electromagnetic valve.

For this purpose, and as shown clearly in Fig. 2, these mechanical connection means 1 9 may comprise a rod 20, integral with the cocking lever 1 8 and one of whose ends, 20a, is hinged to the end 21a of a lever 21 presenting, in its middle part, a pivot pin 22, the other end, 21 b, of lever 21 cooperating directly, by bearing thereon, with the valve 8 of the electromagnetic valve 5.

A return spring 23 urges the mobile equipment thus formed towards the position which tends to move end 21 b of lever 21 away from valve 8.

Rod 20 is preferably disposed parallel to the axis of the electromagnetic valve 5.

The lever arm which separates pin 22 from end 21 a is less than the lever arm which separates pin 22 from end 21 b.

In Figs. 3, 4 and 5, there is schematically shown, in a developed view, the three relative positions occupied by locking pin 11 and cocking lever 1 8.

In Fig. 3, the tap is in its closed position and locked, pin 11 is in its housing 1 3 and cocking lever 1 8 is maintained in its rest position by retun spring 23.

In Fig. 4, the tap is in its unlocked position and it occupies an open position letting the gas pass, the locking pin 11 has engaged cocking lever 1 8 and brought it to a position which maintains valve 8 of the electromagnetic valve 5 open; this position is occupied as long as the user exerts a pushing and rotational movement on the rotating part 1 2 of the tap.

In Fig. 5, the user is not exerting a push on the rotating part 1 2 of the tap, pin 11 has released cocking lever 18 which then returns to its rest position under the action of spring 23 and the user can bring the rotating part 1 2 of the tap to the chosen position for supplying the burner.

Following which and whatever the embodiment adopted, it will be readily understood that the tap in accordance with the invention presents the following advantages: -the lighting of the burner is effected by a succession of gestures natural to the user for it is much easier to maintain the actuating knob of a tap slightly depressed and turned in a certain position than to maintain it depressed over a much greater distance; this is particularly true when it is question of a tap mounted on a horizontal wall.

-the actuating knob of the tap is situated very close to the wall of the apparatus, which is an advantage from the esthetic point of view, not only in the case of a vertical wall but also in the case of a horizontal wall; by way of example, it can be stated that the travel corresponding to the axial unlocking push is about 2 to 3 mm, whereas the travel corresponding to the axial push for maintaining the electromagnetic valve open is of the order of 5 mm; in other words, according to the prior art, it was necessary for the actuating knob to be removed at least 7 to 8 mm from the wall of the apparatus whereas, in the case of a tap in accordance with the invention, this distance is limited to 2 or 3 mm.

-From the constructional point of view, it should be pointed out that the proposed arrangement leads to the construction of an extremely compact tap which may be constructed in sizes such that it is capable of replacing without any other modification the tap constructed in accordance with the prior art.

-Finally, thanks to the dual role played by the locking pin (role of locking member and role of actuating member for the control means of the electromagnetic valve), it is possible to obtain a simple tap, comprising only a limited number of parts, and at a low manufacturing price.

As is evident, and as it follows moreover already from what has gone before, the invention is in no wise limited to those of its modes of application and embodiments which have been more particularly envisaged; it embraces, on the contrary, all variations thereof.

Claims (2)

1. A gas tap for supplying a burner com prising an electromagnetic valve and thermocouple safety device, control means for maintaining the electromagnetic valve open during the time required for current to be established in the thermocouple circuit and a locking means in the closed position formed by at least one pin carried by the rotating part and by at least one housing carried by the nonrotating part, characterized by the fact that these control means comprise, -a cocking lever which is engaged by the locking pin when the rotating part has undergone a rotational movement and is maintained pushed towards the non-rotating part and which is released by said locking pin when the rotating part is no longer maintained pushed against the non-rotating part, -and mechanical connection means between this cocking lever and the mobile part of the electromagnetic valve.

2. A gas tap according to Claim 1, characterized by the fact that these mechanical connection means amplify the movements between the cocking lever and the mobile part of the electromagnetic valve.

2. A gas tap according to claim 1, characterized by the fact that these mechanical connection means are of a type which amplifies the movements between the cocking lever and the mobile part of the electromagnetic valve.

3. A gas tap according to claim 1 or 2, characterized by the fact that these mechanical connection means comprise a rod integral with the cocking lever and one of whose ends is hinged to the end of a lever presenting, in its middle part, a pivot pin, the other end of the lever cooperating with the mobile part of the electromagnetic valve.

4. A gas tap according to claim 3, characterized by the fact that the rod of the connection means is disposed parallel to the axis of the electromagnetic valve.

CLAIMS (8 Nov 1979)

1. A gas tap for supplying a burner comprising an electromagnetic valve and thermocouple safety device, control means for maintaining the electromagnetic valve open during the time required for current to be established in the thermocouple circuit and a locking means formed by at least one pin carried by a rotating part and by at least one housing carried by a non-rotating part, characterized in that these control means comprise, -a cocking lever which is engaged by the locking pin after said locking pin has been unlocked by an axial pushing action of the rotating part towards the non-rotating part and when the rotating part has undergone a rotational movement and is maintained pushed towards the non-rotating part and which is released by said locking pin when the rotating part is no longer maintained pushed against the non-rotating part, -and mechanical connection means between this cocking lever and the mobile part of the electromagnetic valve.