EP0098231B1 - Gas cock with a piezoelectric system, and gas heated apparatus having such a gas cock - Google Patents

Description

The present invention relates to gas taps coupled to piezoelectric ignition systems of a gas burner, for which the rotation of the operating button in the direction of opening of the valve actuates and triggers the piezoelectric system.

In accordance with French patent FR-A-2 330 960 (application no. 7,534,369) in the name of the present Applicant, a gas tap has already been proposed coupled to a piezoelectric system, consisting of at least:

said valve comprising a body, a rotary control axis, comprising at its free end an operating button

said piezo-electric system; this system itself comprises a rectangular housing, a piezoelectric element contained in the latter, a striker movable in the housing relative to the piezoelectric element, a lug for actuating the movable striker, a spring or elastic means disposed in the housing; this system is actuated from its rest position, by means of the lug, by charging the spring, then by projecting the striker against the piezoelectric element, under the effect of the loaded spring;

an intermediate part for actuating the piezoelectric system, consisting of a toothed wheel; this intermediate piece is mounted coaxially with respect to the rotary control axis, and more precisely around a hub belonging to the operating button, between the valve body and said button; each tooth on the periphery of the wheel is capable of actuating the striker of the piezoelectric system;

a means for coupling in rotation the rotary control axis and the intermediate actuating part, in the direction of opening of the valve, the piezoelectric system remaining or returning to its rest position, during the rotation of the control axis in the direction of closing the valve.

In the case of this French patent FR-A-2330960, the latter means is obtained in the following manner:

the toothed wheel is locked in rotation on the hub of the operating button, both in the closing direction and in the opening direction of the valve;

the toothed wheel is free in translation relative to the control axis, and it is pushed against a stop axially fixed relative to the valve body, by a spring disposed between said wheel and the operating button;

in the closing direction of the tap, each tooth of the wheel is pushed back by the lug of the piezoelectric system, and the wheel moves backwards against the spring, with each passage of a tooth against the 'pin, while returning against the stop between two teeth; in this way, the piezoelectric system remains in the rest position, when the tap is closed.

The present invention proposes to improve the technical solution proposed by French patent FR-A-2 330 960, in two aspects: on the one hand, a connection is sought between the tap and the piezoelectric system independent of the gas appliance in which the tap is integrated, and in particular its frame,

on the other hand, in the case where the rotary control axis consists of an axial adjustment screw, a means must be found which makes it possible to actuate the piezoelectric system, whatever the axial position of the axis, during operation of the tap or over time, for example due to wear of the adjusting screw.

In general, according to the invention, there is provided a separate and independent connection of the valve body and the operating button, completely free to rotate relative to the rotary control axis; this connection is mounted at least in part between the valve body and the operating button, and is linked to the piezoelectric system.

According to one embodiment of the invention, the link supports the entire piezoelectric system and at least one means is provided to stop the rotation of the link, at least in the direction of opening of the valve, under the effect of the intermediate actuating part of the piezoelectric system.

One can thus end up with a tap-piezoelectric system connection, in the form of a component independent of the gas appliance, which it suffices to mount on the rotary control axis of the latter: also results in a gain. appreciable in terms of space.

According to another embodiment of the invention, for which the rotary axis is an axial adjustment screw; an axial stop is provided on the rotary control axis, and the link is mounted. at least in part between this stop and the start button. In this way, the piezoelectric system is permanently subjected in translation to the axial movement of the control axis. If, moreover, the intermediate actuating part is itself fixed in translation relative to the adjusting screw, this completely frees itself from the axial displacements of the rotary control axis, in order to actuate the piezoelectric system with from the tap rotation.

• Figure 1 est une coupe longitudinale d'un système piézo-électrique de type simplifié.
• Figure 2 montre en perspective avec arrachement un système piézo-électrique à fonctionnement autonome.
• Figure 3 illustre l'utilisation d'un système piézo-électrique tel que celui de Fig. 1, associé à une pièce d'actionnement assujettie à l'axe rotatif d'un robinet à gaz.
• Figure 4 est une vue partielle avec arrachement, montrant la liaison entre la pièce d'actionnement et l'axe rotatif du robinet.
• Figure 5 est une vue éclatée de la pièce d'actionnement illustrée en fig. 3 et 4 et de son moyen d'accouplement à échappement avec l'axe rotatif.
• Figure 6 illustre en perspective une autre manière de réaliser la pièce intermédiaire d'actionnement du système piézo-électrique.
• Figure 7 montre un robinet à gaz couplé à un système piézo-électrique au moyen d'une pièce intermédiaire d'actionnement telle que celle illustrée en fig. 6.
• Figures 8 à 15 sont des schémas qui illustrent le fonctionnement de la pièce intermédiaire d'actionnement illustrée en fig. 6 en association avec un bouton de manœuvre.
• Figures 16 et 17 montrent un robinet à gaz couplé à un système piézo-électrique similaire à celui montré selon fig. 7 à 15, mais différent de celui-ci par le mode de support du mécanisme piézo-électrique.

The appended drawing, given by way of example, will allow a better understanding of the invention, the characteristics which it presents and the advantages which it is capable of providing:

• Figure 1 is a longitudinal section of a piezoelectric system of simplified type.
• Figure 2 shows in perspective with cutaway a piezoelectric system with autonomous operation.
• Figure 3 illustrates the use of a piezoelectric system such as that of FIG. 1, associated with an actuating part subject to the rotary axis of a gas valve.
• Figure 4 is a partial view with parts broken away, showing the connection between the actuating part and the rotary axis of the valve.
• Figure 5 is an exploded view of the actuating part illustrated in fig. 3 and 4 and its exhaust coupling means with the rotary axis.
• Figure 6 illustrates in perspective another way of making the intermediate actuating part of the piezoelectric system.
• Figure 7 shows a gas valve coupled to a piezoelectric system by means of an intermediate actuating part such as that illustrated in fig. 6.
• Figures 8 to 15 are diagrams which illustrate the operation of the intermediate actuating part illustrated in FIG. 6 in combination with an operating button.
• Figures 16 and 17 show a gas tap coupled to a piezoelectric system similar to that shown in fig. 7 to 15, but different from it by the support mode of the piezoelectric mechanism.

The piezoelectric system 8 illustrated in fig. 1 comprises in known manner an elongated housing 1 at the end of which is fixed a piezoelectric element 2, against which a striker 3 is projected displaced by a pushing member 4 against the reaction in the opposite direction of an elastic means 5. As is well known, the striker brought to the bottom of the travel by the thrust member is released, so that under the reaction of the spring 5 it strikes the piezoelectric element causing it to produce a electric tension.

In Fig. 2 a more sophisticated system 8 has been illustrated, the piezoelectric element 2 of which is always retained at one of the ends of the casing or housing 1, but the striker 3 is associated with a pushing member 6 which can be moved telescopic relative to the envelope 1. This member is returned to its rest position by a spring 7. We will not return to the operation of such a piezoelectric system which is well known in practice. It will simply be recalled that from its rest position, the displacement of the thrust member towards the casing 1 makes it possible to load the springs 5 and 7, then to project the striker against the piezoelectric element, the return to the rest position of the pushing member being effected under the sole effect of the spring 7, all thanks to ramps judiciously disposed on the pushing member, as described in EP-A- 0054504 (claiming priority from French patent application 8 026 988) of the present Applicant, this document EP-A-0 054 504 falling under Article 54 (3) of the EPC.

In fig. 3, 4, 5, a piezoelectric system such as that shown in fig.1 is used. We find in these figures the housing of the piezoelectric system produced in one-piece form with the support or link 9, itself comprising an elongated body 9a and two side cheeks 9b determining between them a certain space below which the side wall of the body 9a is cut to form a slot 9c. Inside the body 9a is placed the piezoelectric element 2 held in place by a threaded metal plug referenced 10 with which cooperates an output conductor 11 kept applied against the plug 10 by means of an insulating capsule 12. A inner groove 12a of the capsule 12 engages with a cord 9d formed for this purpose at the periphery of the body 9a. Similarly, a second capsule 12 is secured to the other end of said body in order to serve as a stop at one of the ends of the spring 5 for actuating the striker 3, the opposite end of which bears on the latter or more precisely at the bottom of a depression 3a thereof. An intermediate actuating part 13 placed between the cheeks 9b is mounted for rotation about the rotary axis 14 of a gas tap 15 with an axial adjustment screw; this part is fixed in translation relative to the axis 14. The periphery of the intermediate actuating part 13 is provided with teeth 13a intended to come to cooperate with the front face 3b of the striker 3 in order to make it move back to against the reaction of the spring 5. It is easily understood that the rotation of the intermediate actuating part causes the retractor of the striker then its release so that it can strike the element 2. The electric charge obtained.is routed towards the burner, on the one hand by the electric wire 11, and on the other hand by the striker 3, the wheel 13, the axis 14 and the body 15 of the valve, and if necessary with an electric arc between the striker 3 and the wheel 13.

To do this, it suffices that the intermediate actuation part is integral with the rotary axis 14 in the direction of opening of the valve 15. On the other hand, it is necessary to disengage this intermediate actuation part and the axis 14 when the tap is closed.

For this purpose, the face of the part 13 which is oriented opposite the tap 15 is provided with four ramps 13b (fig.5) ending in steps 13c. Against the face in question of the part 13, comes to carry an open washer 16 surrounding the axis 14 and one of the ends 16a of which is suitably arched cooperates with the ramps 13b as will be better explained below. The opposite end of the washer 16 is deformed in order to form a tab 16b perpendicular to its general plane. This tab 16b enters a slot 17a (FIG. 5) of the operating button 17 of the axis 14, so that the rotation of this button in the direction of opening causes that of the actuating part 13, by abutment of the end 16a of the washer 16 against the steps 13c. In the opposite direction, the washer 16 rubs against the ramps 13b without driving them. Of course, the operating button 17 is force fitted or overmolded on the grooved end 14a of the axis 14. The connection 9 being placed transversely relative to and on the axis 14, the rotation of the intermediate piece 13 could l 'Drive if it had a heel 9th which cooperates with the valve 15 to wedge it angularly.

It is observed that the axis 14 includes a flange 14b against which bears the outer face of one of the cheeks 9b of the support 9, the inner face of this cheek constituting a stop for the actuating part 13, against which bears with operating clearance the end of the hub 17b formed on the operating button 17, itself crossing the other cheek 9b of the support 9. Thus, the latter is linked longitudinally with respect to the axis 14.

Thus, it is possible to use the pleoelectric device and its drive as described above, whether the valve 15 is of the plug or needle type, that is to say that its rotary axis may or may not be subjected to a longitudinal translation, without influencing its operation.

In the embodiments illustrated below, we are no longer dealing with a piezoelectric system according to FIG. 1, but on the contrary with a system such as that illustrated in FIG. 2, and which is oriented parallel to the rotary valve control axis.

In the embodiment of fig. 6 and 7, the intermediate actuating part 20 comprises a ramp 20a which develops from a low point to a high point located on either side of a tongue 20d. The same goes for a control element 21 which is provided with a ramp 21c whose top and bottom points are located on either side of a stop 21d. As the control element remains angularly fixed, the tongue 20d is blocked during the rotation of the part 20 on the side of the low point F of the ramp 21c in the position of closing the valve, and on the side of the point O of the same ramp 21c in its open position. It is observed that the ramps 20a and 21c of the piece 20 and of the element 21 each comprise a neutral zone 20e respectively 21e placed at the low point of each ramp and another neutral zone 20f, 21f disposed at the top of each ramp. The areas in question are actually flat areas, the role of which will be better explained below.

Note that the ends of the tongue 20d and of the stop 21d are respectively in abutment against the ramp 21c and that 20a, when said part 20 and the control element 21 are in abutment against one another.

The housing 1 of the piezoelectric system is contained, parallel to the axis 14, in a support produced in the form of a carcass 19 resting against a face of the valve 15. This carcass is extended by a lateral tab 19a through which the 'rotary axis 14, the end branch of said tab being folded back to cooperate with a second face of the valve 15 oriented parallel to the first. The side tab 19a is trapped between the flange 14b of the rotary axis 14, the control element 21, and an intermediate actuating part 20 on which acts, as will be described better below, the operating button 17 of the tap 15. The intermediate actuating part no longer acts directly on the thrust member 6 of the piezoelectric system, but it is engaged with the control element 21, intended to act on the thrust member 6 of the piezoelectric system. This control element 21 comprises the ring 21a provided with the ramp 21e and the finger 21 b, the end of which enters the carcass 19, with a view to acting on the thrust member 6. Of course, the length of the finger 21 b is calculated so that its curved end remains constantly inside the carcass 19, even when the valve is fully open. To protect the periphery of the intermediate actuating part 20 and the control element 21, the control button 17 is advantageously extended by a tubular sleeve .17d at least partially surrounding said periphery.

The operation of the gas tap comprising a mechanism for actuating the piezoelectric system in accordance with FIGS. 6 and 7 follow from the foregoing explanations.

Fig. 8 is a developed view of the two ramps 20a and 21c. When the tap is closed, these two ramps are in contact with each other, except for the neutral zones 20f and 21f of each of them. It is observed that the end of the finger 21 b is in abutment against that of the pushing element 6 of the piezoelectric system, in such a way that the depression of this member inside the carcass 19 in no way causes case the triggering of the piezoelectric system. As illustrated in fig. 9, a mark 22 placed on the operating button 17 is located opposite a sign 23 indicating the closing of the valve. If the knob 17 is turned anticlockwise, therefore in the direction of opening the tap, the end of the tongue 20d pushes the control element 21 towards the tap, so that the finger 21 b of this element actuates the member 6 of the piezoelectric system, so as to cause a spark to burst, for example when the mark 22 is at the level of an index 24 (cf. Figs. 10 and 11). At this moment, the end of the tongue 20d arrives just at the start of the flat area 21f of the ramp 21c. Thus, from this position, one can continue to open the tap in order to perfect the adjustment of the gas outlet, without action on the thrust member 6, that is to say that one can adjust the tap at an angle without affecting the piezoelectric system (see fig. 12 and 13). It is observed that in the open position of the valve, the pushing member 6 remains pressed beyond the position in which it has caused the striker to project against the piezoelectric element.

If ignition does not occur, it is of course necessary to return to the initial position of fig. 8 and 9 and repeat the operation.

The presence of the teeth 20c and the teeth 17c allows during wear of the needle or the valve seat to make up for this play by rotation of the control button 17. In fact, if there is wear on the valve seat, the rotation of button 17 should be greater than before to obtain complete closing of the tap, and the closing position will automatically change to a new position (in the F1 direction), thanks to the possibility of rotation of the button 17 relative to the part 20.

As illustrated in fig. 14 and 15, the displacement of the intermediate piece 20 in the closing direction causes the teeth 17c of the operating button to be released relative to the teeth 20c of the piece 20, the latter and the element 21 moving alternately from axially against the reaction of the return means of the thrust member 6.

When a gas appliance incorporates a tap coupled to a piezoelectric system, as described above in these different variants, the support or connection of the piezoelectric system is also independent of the frame of the appliance.

According to the embodiment in accordance with FIGS. 6 to 15, the carcass 19 constitutes both the support of the piezoelectric system 8 and the connection between the latter and the rotary control axis 14 (thanks to the stop 14b), to subject in displacement the movement of said system to that of the axis 14 (adjusting screw).

According to the embodiment according to Figures 16 and 17, all the constituent and structural parts described above with reference to Figures 6 to 15 remain identical in their respective functions.

But according to this embodiment, the support of the piezoelectric system is dissociated and the connection in translation between the latter and the control axis. More precisely, according to FIG. 16 (top view, with partial section along the section plane XVI / XVI of FIG. 17) and according to FIG. 17 (front view, with partial section along the section plane XVII / XVII of Figure 16), the piezoelectric system 8 is disposed in a housing 50 of plastic material, made integral with the valve body 15, by screwing a part (not shown) on the thread 15v, which blocks the housing 50 against the 15w tap barrel. The piezoelectric system 8 can move in translation in the housing 50. The connection between the system 8 and the axis 14 consists of a lug 51 comprising a part 51a in abutment against the part 14b of the axis, another part 51 b at right angles entering the housing 50, along the mechanism 8, and a last 51c at right angles and in the opposite direction from the part 51a, bearing against the rear of the system 8; this support is obtained permanently thanks to the reaction of the pushing member 6 against the finger 21b, provided that the length of the part 51b is correctly dimensioned relative to the stroke of the pushing member 6. In this way , the piezoelectric system 8 continuously follows the axial movement of the axis 14.

Claims (11)

1. Gas cock coupled to a piezoelectric system, constituted by at least :

the said cock (15) comprising a body, a rotary driving axis (14) with an operating button (17) at its free end,

the said piezoelectric system comprising at least one case (1), a piezoelectric element (2) contained in the latter, a movable striker (3) in the case in relation to the piezoelectric element, an elastic means (5) arranged in the said case, the said system being actuated from its position of rest by charging the elastic means, then by projecting the striker against the piezoelectric element under the effect of the charged elastic means,

an intermediate piece (13, 20) to actuate the piezoelectric system, mounted coaxially in relation to the rotary driving axis (14), between the body of the cock (15) and the operating button (17), comprising on its periphery at least one activating member (13a, 20a) of the piezoelectric system,

a means (16, 17b, 20c) allowing the rotary driving axis (14) to be coupled in rotation to the intermediate actuating piece (13-20), in the direction of opening the cock, the piezoelectric system remaining at or returning to its position of rest, when the rotary driving axis is rotating in the direction of closing the cock, characterized in that it comprises a connection (9, 19, 51) which is independent of the body of the cock (15) and of the operating button (17), is free in rotation in relation to the rotary driving axis (14) and mounted at least in part between the said body and the said button, and connected to the piezoelectric system (8).

2. Cock according to Claim 1, characterized in that the connection (9) bears the whole of the piezoelectric system (8), and at least one means (9e) is provided to stop the rotation of the connection, at least in the direction of opening the cock.

3. Cock according to Claim 1, the rotary axis (14) being an axial regulating screw, characterized in that the intermediate piece to actuate the piezoelectric system is fixed in translation in relation to the rotary axis, and an axial stop (14b) is provided on the rotary axis (14), the connection being mounted at least in part between the said stop and the operating button, so as to fix the piezoelectric system (8) in translation on the axial displacement of the driving axis.

4. Cock according to Claim 3, characterized in that a housing (50) is provided which is integral with the body of the cock (15), in which the piezoelectric system (8) is arranged freely in translation.

5. Cock according to claim 2, according to which the piezoelectric system has an elongated shape and contains in an aligned manner on one side the piezoelectric element (2) and on the other side the striker (3) pushed back toward the said element by the elastic means (5), an opening (9c) being provided in the. case for the actuation of the striker, characterized in that the piezoelectric system is positioned on the connection (9), in relation to the intermediate actuating piece (13), in a manner such that by rotation of the latter in the direction of opening the cock, the piezoelectric system is actuated through the opening of the said system, the striker being pushed back in one direction by the actuating member (13a), in opposition to the elastic means (5), then escaping the said member to strike the piezoelectric element (2) in the other direction under the sole effect of the charged elastic means.

6. Cock according to Claim 2, according to which the piezoelectric system comprises a case (8) constituted by a jacket (1) and a thrust _° member (6) which is movable in translation on the said jacket, and a returning means (7) towards the position of rest, the said system being actuated from its position of rest by displacing the jacket and the thrust member one towards the other in translation, this deplacement allowing the returning means and the elastic means of the striker to be charged, then allowing the latter to be prp- jected against the piezoelectric element, the return to the position of rest being carried out under the sole effect of the returning means, characterized in that on the one hand the actuating piece (20) comprises a slope (20a) with a part rising in the direction of opening the cock, and on the other hand the piezoelectric system is positioned on the connection (19), in relation to the intermediate actuating piece, in such a manner that, by rotation of the latter in the direction of opening the cock, the jacket (1) or the thrust member (6) of the piezoelectric system is displaced under the action of the rising part of the slope, at least up to the projection of the striker (3) against the piezoelectric element (2).

7. Cock according to Claim 6, characterized in that a driving element (21), mounted coaxially and movable in translation in relation to the axis (14), is arranged the piezoelectric system and the intermediate actuating piece (20), and comprises on one side a push-piece (21 b) situated against the jacket (1) or the thrust member (6) of the piezoelectric system, and on the other side a counter actuating member (21d) resting against the slope (20a).

8. Cock according to Claim 6, according to which the piezoelectric system returns to its position of rest when the rotary driving axis rotates in the direction of closing the cock, characterized in that on the one hand the slope stretches from a low point to a high -point, situated on both sides of a tongue (20d), and on the other hand a stop (21d) is provided which is fixed angularly in relation to the rotary driving axis against which stop the tongue is locked, when the intermediate actuating piece (20) rotates, from the low point of the slope in the position of closure of the cock, and from the high point in the position of closure of the cock, and from the high point in the position of opening of the cock.

9. Cock according to Claims 3 and 8, characterized in that the means (16, 17c, 30c) allowing the rotary driving axis (14) and the intermediate actuating piece (20) to be coupled in rotation joins these latter together in the direction of opening the cock, and permits, in the direction of closing the cock, a relative rotation between the axis and the intermediate piece, this latter being locked in rotation in the direction of closure.

10. Gas apparatus incorporating a gas cock coupled to a piezoelectric system according to any one of Claims 1 to 9, characterized in that the connection (9, 51) of the piezoelectric system is independent of the framework of the apparatus.

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