FR2583506A1 - Gas tap equipped with a safety valve and having a reduced height requirement, for hotplates and gas cooking appliances, in particular for cookers - Google Patents

Abstract

The gas tap comprises a safety valve and has a reduced height requirement. It further comprises a tap part proper R controlled by a rod 13 able to move axially, a safety valve part S which comprises a thin actuating rod, a connection part SR for connecting to the gas supply pipe 10 coming from the distribution main, a series of ducts defining a path for the gas leading from the point of connection to the supply pipe 10 to the point of connection 38 to the burner, passing via the three parts R, S, SR; and a kinematic chain allowing the axial movement of the tap part R to be transmitted to the thin rod 34 for manoeuvring the safety valve. Used for equipping gas cookers.

Description

The present invention relates generally to gas taps for hot plates and gas cooking appliances and in particular gas taps provided with a safety device, that is to say the so-called "taps". with safety valve ". These taps are characterized in that they have a reduced vertical footprint, which makes them particularly suitable for use in connection with hot plates of gas stoves and the like.

A particularly important aspect of the present invention relates to the kinematic chain making it possible to maneuver, by means of the usual button, the thin rod of the assembly comprising the safety valve. As is well known, the so-called safety valves of which
are equipped with many types of gas valves including
a small disc that rests on a pierced diaphragm,
in a cylindrical channel, under the effect of an exer spring
cracking a push. This small disc is worn at the end
a small piston, the other end of which is opp
pole pieces of an electromagnet.

This electromagnet receives a produced current
by a thermocouple under the effect of the supplied heat
by the gas flame. The pull of electro
magnet acts in a direction opposite to the force supplied
by the spring and is stronger than the latter. When
that the electromagnet ceases to be excited, that is to say
when the flame is extinguished or in the process of extinction,
the force of the spring pushes the small disc into position
closing. When the flame is active, the current
generated by the thermocouple excites electro-ai-
mant whose force of attraction overcomes the force of res
pulls out and keeps the thin rod attracted and the disc rela
very small in the open position.

This device, acting as described
in the above, is already known per se and widely
used. However, it requires manual operation beforehand to allow the use of the gas stove. Indeed, as the electromagnet is not excited when the flame is nonexistent, and as the valve is then closed, it is necessary to keep it in the open position, by a manual operation, in order to allow a gas flow to pass to allow the ignition of the flame. The valve is manually maintained in the open position, until the flame produced generates the current necessary for the excitation of the electromagnet. When the electromagnet is energized, it keeps the valve open, without manual intervention being necessary.

 In order to avoid the use of two control devices, the operation of the thin valve stem is carried out by means of the ignition or adjustment button stem. As is well known to those skilled in the art, all this implies, for the tap provided with a safety valve of the usual type described above, a considerably increased external bulk in the direction of the axis of the button. . This fact can be of negligible importance, or without interest, in the case of stoves and cooking appliances presenting no problem of limitation of available space. On the other hand, this problem is extremely annoying in the case of cookers. Indeed, one of the main characteristics of the stoves used in cooking is that the axes of their buttons are arranged vertically while it is at the same time required to have very small thickness dimensions, so that it is impossible to use gas taps provided with safety valve.

 The solution to this problem consists, in principle, of making the axis of the button independent of the axis of the safety valve. If it is necessary to avoid the use of two control devices, and if a functional connection is desired between the ignition button and the stem of the safety valve, the solution of this problem involves the production of fairly complicated structures , which are also expensive although providing a long-term safety feature.

 Thus, the general object of the present invention is to provide a gas valve provided with a safety valve, in which the axis of the safety valve is, as regards its position, independent of the axis of the ignition button while being functionally linked to it.

 Another, more particular, object of the present invention is to provide a kinematic chain capable of transmitting an axial movement from the ignition button to the manual actuation rod of the safety valve, to allow the supply of gas and the ignition of the flame when the electromagnet is in the unexcited state.

 Another object of the invention is to produce a structure of the aforementioned type, in which the pressure of the gas from the distribution network is such that it keeps the safety valve closed and ensures the automatic tight closure of the latter, even in the case of overpressures.

 According to the basic embodiment, the valve according to the invention comprises a valve part provided with a control button mounted on an axially movable rod, a safety valve part whose axis is not aligned with the axis of the tap part and more particularly is perpendicular thereto, and provided with a thin rod for manual actuation and a connection part for making the connection to the gas supply pipe coming from the distribution network, a conduit or a series of conduits defining a path for the gas going from the connection point to the supply pipe to the connection point to the burner, passing through the three aforementioned parts as well as a kinematic chain which makes it possible to transmit the axial movement of the button rod from the tap part to the thin rod provided for manual actuation of the safety valve.

 According to a preferred embodiment of the invention, the tap part comprises a lower chamber extending upwards in the form of a conical cavity through which an opening in this leads to the external connection for the burner, and the he well known conical member, carrying holes for maximum flow and minimum flow, adjustable by needle, is housed in said chamber.

This conical member can be actuated by means of a conventional button which can perform, in addition to the rotational movement for adjusting the gas flame by means of the conical member, an axial movement for manual actuation of the valve. of security. A small transverse pin is connected to the rod of the button, this small pin constituting the first element of the above-mentioned kinematic chain.

 According to another preferred embodiment of the present invention, the safety valve part is arranged transversely to the tap part and has an internal cavity which a diaphragm or partition pierced subdivides into an upstream chamber and a downstream chamber. A small piston is housed in the upstream chamber, this piston carrying at one of its ends a small disc or plate which a spring urges towards said diaphragm pierced so as to close the communication between the upstream chamber and the downstream chamber. In addition, the upstream chamber also contains an electromagnet that the current generated by a thermocouple under the effect of the gas flame excites to keep the other end of the small piston attracted despite the antogonistic force of the support spring. , so as to establish communication between the upstream chamber and the downstream chamber. The upstream chamber communicates with the gas supply pipe, while the downstream chamber communicates with the lower chamber of the tap part.

 The connection part, to make the connection to the gas supply pipe, advantageously comprises, to make this connection, a seat with two jaws, which can be moved and tightened, to grip the gas supply pipe, and a spout pierced which is inserted into the supply pipe and communicates, via an internal conduit, with the upstream chamber of the part comprising the safety valve.

 A path for the gas is thus defined by means of the structural characteristics outlined in the foregoing, this path extending from the connection to the gas supply pipe, through the connection part, to the inlet of the part safety, then through the upstream chamber thereof, the pierced diaphragm, and its downstream chamber, then from the outlet of the safety part to the lower chamber of the tap part and, from this chamber, through the holes for the maximum or minimum gas flow from the conical member of the valve, and through the connection pipe going to the burner.

Among the various possible embodiments, the invention further provides, in particular, that
- the kinematic chain for manual actuation (opening action) of the safety valve comprises a transverse pin fixed to the rod of the button, this pin being adapted to rest on the head of an assembled pin so that it can slide vertically in the body of the tap part, in a direction parallel to the axis of the button, a first tongue cooperating with the lower end of the pin sliding vertically, this tongue being fixed to one end of a small shaft so to rotate with the latter which is mounted transversely, in a rotary manner, in the base of the valve body, and a second tab fixed to the other end of this small shaft so as to rotate integrally with it and to cooperate with the thin rod for manual actuation of the safety valve;
- The transverse spindle is small and passes through a slot in the envelope of the tap part, this slot defining the stop positions for rotation of the button;
- The position at which the small spindle is above the head of the spindle mounted for vertical sliding is an intermediate position between the stop positions of rotation of the button rod to which this small spindle is fixed.

Other details, characteristics and advantages of the present invention will become apparent in the description below. In the accompanying drawings given by way of nonlimiting example
- Figure 1 is a perspective view, from above, of a gas valve according to the invention;
- Figure 2 is a top view, in partial section, of this gas valve;
- Figure 3 is an axial sectional view of the part comprising the safety valve;
- Figure 4 is a view of the gas valve considered in a longitudinal section made along the axis of the button rod;
- Figure 5 is another perspective view, from above, of the gas valve, showing the arrangement of the kinematic chain for manual actuation of the safety valve by means of the button; and
- Figure 6 is a diagram of the valve adjustment positions.

Referring to the drawings, it can in particular be seen that the gas valve forming the subject of the present invention can be considered to be made up of three main parts, namely a valve part.
R, a safety part S and a connection part SR making the connection to the gas supply pipe 10.

The valve also includes a kinematic chain for transmitting movement between the valve part R and the safety part S.

 In FIG. 4, the tap part R comprises a body 16 having internally a lower chamber 11 extended upwards by a conical or flared cavity 11a in which the conical member 12 is housed, which is linked in a manner allowing an axial sliding, but in a non-rotary manner, to the rod 13 which is inserted in the control button 14. A helical compression spring 15 is placed between the conical member 12 and the base of the rod 13.

 A conduit 21 (see FIG. 6) is provided in the body 16, at a location corresponding to the wall of the conical cavity 11a, this conduit 21 acting as a connection between the conical cavity 11a and the connection member to the outside , to conduct the gas to the burner. The conical member 12 (see FIG. 4) has a lower centered cavity from which there emerge, in known manner, two inclined holes, namely a large hole 17 for the maximum gas flow and a small hole 17a for the gas flow minimal. The minimum flow rate is adjusted by means of a needle-type member 18 carrying a threaded head. This needle is accessible through the longitudinal hole 19 arranged in the rod 13 which is inserted in the button 14.

 A small lateral pin 20 is fixed to the base of the rod 13 of the button, the fixing being obtained for example by screwing. In what follows, we will explain the function of this side pin which represents the first component of the kinematic chain already mentioned.

 The supply of gas flow to the burner nozzle only occurs when one or the other of the two inclined holes 17 and 17a of the conical member comes to occupy a position corresponding to the connecting duct 21 drilled in the wall of the body 16 from the tap. Purely schematic, presented by way of nonlimiting example (in particular as regards the shape, the size and the position of each hole, as well as the angular extent of the ranges of rotation), FIG. 6 shows that, in the closed position, none of the holes 17 or 17a is in correspondence with the hole 21, while in the position of supply of gas at normal flow rate the large hole 17 supplies the gas flow to the hole 21 and that, in the position of supplying gas at the minimum flow rate, it is the small hole 17a which supplies the flow of gas to the hole 21. As already mentioned above, the rotations at 900 are indicated by way of nonlimiting illustration , the shapes and positions of the holes, therefore the angles of rotation, being in practice adapted to the needs of continuity and the degrees of adjustment, as well as to legal regulations and standards.

 It should be noted that there is an intermediate position of maximum flow when passing from the stop position in which the gas flow is interrupted, to the stop position in which the gas flow is minimal, the small spindle 20 being, in this intermediate position, located above the head 22 of the spindle 23 which represents the second component of the kinematic chain.

 The safety part S represented in FIG. 3 comprises a body 24 (which is the same as that identified by the reference 16 in FIG. 4), the interior cavity of which is subdivided into an upstream chamber 25 and a downstream chamber 26 which are separated by a perforated diaphragm or partition 27. An electromagnet 28 is housed in the upstream chamber 25 and acts on the end of a small piston 29 carrying at its other end a small disc or cap 30 provided with a seal suitable sealing. A spring 31 providing a compressive force pushes the small disc or cap 30 against the pierced diaphragm 27, so as to close the latter.

A conduit 32 coming from the connection part
SR leads to the upstream chamber 25, while the pipe 33 leads from the downstream chamber 26 to the lower chamber 11 of the tap part R already described with reference to FIG. 4.

 Concretely, when the electromagnet 28 ceases to be excited, the spring 31 pushes the small disc or cap 30 against the opening made in the diaphragm 27, so as to close this opening and to prevent any communication between the upstream chamber 25 and the downstream chamber 26.

Since the electromagnet is excited under the effect of the thermal current due to the action of the gas flame, for example on a thermocouple, as is well understood, it follows that no gas flow does not pass in the absence of flame. At the beginning, to light the flame it is necessary to intervene from the outside on the small disc 30, so as to open the passage through the perforated diaphragm 27. This operation is carried out by means of an axial rod 34 protruding from the end of the body 24. This rod can act, through the opening in the perforated diaphragm 27, on the small disc or cap 30. More particularly, it can be noted that by pushing the thin rod 34 inwards the small disc 30 can be moved away from the perforated diaphragm 27: communication is thus established between the upstream chamber 25 and the downstream chamber 26, and the gas can flow from the duct 32 to the duct 33. The small disc or cap 30 is maintained forced apart from the pierced diaphragm 27 by means of the thin rod 34 which then opposes the action of the spring 31, until
that the gas flame gives rise to a thermal current sufficient to cause the excitation of the electromagnet 28. At this point, the electromagnet 28 thus excited retains the small piston 29 so as to keep the path open of communication between the upstream and downstream chambers, respectively 25 and 26, and to maintain at its normal value
the gas flow supplied to the flame. The thin rod 34 is returned to its rest position by the pous spring
35. If the flame is extinguished, the electric current of thermal origin exciting the electromagnet 28 is then no longer generated, so that the valve closes and then
that the spring 31 pushes the small disc 30 against the
diaphragm pierced.

Two important remarks must be made, which con
identify the operation of the device described. The first one
is that the attraction force of the electromagnet must
be greater than the pushing force of spring 31, otherwise
the electromagnet could not overcome the force of the
spring 31 to keep the valve open.

The second remark concerns an advantageous aspect.
geux of the present invention: when the valve is
in the closed position, the upstream chamber 25 is located at the
pressure from the gas supply network, and this pressure
acts on the small disc 30 in the same direction
that the spring 31, that is to say in the direction of
the closed position, so that the gas pressure makes it easier to keep the valve in this closed position. All this is very advantageous, not only for safety, but also for the sealing members located downstream of the diaphragm 27. In fact, the latter are exposed to the pressure of the gas only if the tap is open and the burner on.

 Examination of FIGS. 1, 2 and 5 shows that the connection part SR comprises a seat with two jaws 36, 37 by which the tap is connected to the gas supply pipe 10. Such a connection structure is already known per se . We will only mention the spout 32a (Figure 5) which forms the mouth of the conduit 32 leading to the upstream chamber 25 of the safety part.

 To summarize the gas path, we can see that the gas flow from the supply pipe 10 enters through the nozzle 32a, passes through the conduit 32 and enters the upstream chamber 25 of the safety part, then crosses the pierced diaphragm 27 and enters the downstream chamber 26 then passes through the conduit 33 leading to the lower chamber 11 of the tap part, chamber from which the gas flow passes through one of the two inclined holes 17 or 17a of the conical member 12 and through the hole in the connecting duct 21 leading to the pipe 38 for supplying the burner.

 The kinematic chain constitutes an essential aspect of the present invention. This kinematic chain allows the safety valve to be actuated manually to ignite the gas by acting directly on the ignition button.

As already indicated above, the rod 13 on which the button 14 is inserted is linked to the conical member 12, so as to allow sliding, but not rotation, relative to this member, according to a well known practice. This means that this rod can transmit a rotational movement to the conical member 12 and that this rod can also slide longitudinally relative to this member. The rod 13 carries a transverse pin 20 which is fixed to the rod 13, for example by screwing, this small pin imposing the positions for stopping the rotation of the button 14 coming into abutment against the ends of a slot provided in the '' - from the tap part. This small spindle 20, when placed in an intermediate position between said stop positions, is superimposed on the head 22 of spindle 23. In addition to these first two components 20 and 22, the kinematic chain for manual actuation
(opening action) of the safety valve further comprises a first tab 39 (see Figure 5) which is fixed to one end of a small shaft 40 so as to rotate with it. This small shaft is mounted, with the possibility of rotation, in the base of the valve body, and carries at its other end a second tongue 41 which can rotate with it in an integral manner, like the first. The first tongue 39 cooperates with the lower end of the pin 23, while the second tongue cooperates with the outer end of the thin rod 34.

 The device operates as follows.

Starting from the closed position in which the small pin 20 occupies its stop position, the button 14 is rotated to an intermediate position corresponding to the maximum gas flow, so that the small pin 20 is superimposed on the head 22 of pin 23.

The button 14 is then pressed, pushing the pin 23 down. This pin 23 pushes, by its lower end, the first tongue 39 which rotates so as to rotate the small shaft 40 at the same time as the second tongue 41 disposed at its other end.

 This second tongue 41 rotates so as to push the thin rod 34 inwards, against the action of the spring 35, while the thin rod 34 presses on the small disc or cap 30 of the safety valve.

Thus, this safety valve (small disc or cap 30 and pierced diaphragm 27) is kept open until the button 14 is pressed so as to allow the passage of the gas flow necessary for ignition. When the electromagnet 28 is energized, the button can be released and turned to the desired setting, while the kinematic chain is brought back to the initial conditions under the action of the spring 35.

 An advantage of the gas valve as shown and described in the foregoing resides in the fact that this valve has a reduced size allowing it to be mounted in place of other gas valves not provided with a safety device. Thus, the cooking plates of cookers can be indifferently provided with taps with or without safety device, without the need for auxiliary devices, covering members and other equipment, to achieve the same result.

 In addition, the kinematic chain described allows the entire valve to be arranged to the right or left of the valve, the values of the distances, heights and angles being able to be adapted to the different material requirements.

 The accompanying drawings and the preceding description simply relate to a preferred embodiment of the invention, which is not limiting. Modifications, as well as the use of equivalent means, are possible without departing from the scope of this invention.

Claims (13)

 1. Gas tap provided with a valve and having a reduced overall height, for hot plates and gas cooking appliances, in particular for stoves, characterized in that it comprises a tap part proper (R) provided with a control button (14) mounted on an axially movable rod (13), a safety valve part (S) whose axis is not aligned with the axis of the tap part and more particularly is perpendicular to this axis , and comprising a thin rod (34) for manual actuation, a connection part (SR) for making the connection ad pipe (10) of gas supply from the gas distribution network, a conduit or a series of conduits defining a path for the gas from the point of connection to the supply pipe to the point of connection to the burner, passing through the three aforementioned parts (R, S, SR), and a kinematic chain capable of transmitting the axial movement of the rod (13) of the button (14) of the part tap (R) with thin rod (34) for manual actuation of the safety valve.  2. Tap according to claim 1, characterized in that the tap part (R) comprises a body (16) which internally comprises a lower chamber (11) extending upwards in the form of a flared cavity (lla) in which is housed a conical member (12) which is aligned with the rod (13) of the button (14) and with which it is connected in a sliding manner axially but not rotatable, and in that a connecting duct (21) is provided in the conical body which extends through the wall of the flared cavity (IIa). this conduit connecting the flared cavity to the external connection of the burner.  3. Tap according to claim 2, characterized in that the conical member (12) has a central cavity from which extend two inclined holes (17, 17a) which are designed for the maximum flow and the minimum flow of gas flow and which are adapted to occupy a position corresponding to the duct (21) to establish the connection with the external connection of the burner.  4. Tap according to claim 3, characterized in that the minimum flow hole (17a) can be adjusted by means of a needle element (18) having a threaded head and which can be reached through an axial hole (19) formed in the rod (13) of the button (14).  5. Tap according to claim 1, characterized in that the valve forming the safety part (S) comprises a body (24) whose inner cavity is subdivided into an upstream chamber (25) and a downstream chamber (26), these chambers being separated by a pierced diaphragm (27), and in that an electromagnet (28) is housed in the upstream chamber (25), this electromagnet being excited by the electric thermal current generated by the action of the flame of the burner on a thermocouple and acting on the end of a small piston (29) having at its other end a small disc or cap (30) provided with a seal, a spring (31) being designed to push the disc or cap (30) against the drilled diaphragm (27) so as to close it, in that a conduit (32) coming from the connection part (SR) leads to the upstream chamber (25) while another conduit (33) leads to the lower chamber (11) of the tap part from the downstream chamber (26), and in that a mi This axial rod (34) is mounted in the downstream chamber (26), this rod projecting from the end of the body and being capable of acting on the small disc or cap (30) by crossing the opening in the diaphragm (27 ), and being kept apart from the disc (30) by means of a compression spring (35).  6. Tap according to claim 5, characterized in that the attraction force of the electromagnet (28), when the latter is excited, is greater than the pushing force that the spring (31) exerts on the small disc (30) in the direction of the pierced diaphragm (27).  7. Valve according to claim 5, characterized in that, when the valve (27.30) is closed, the pressure of the gas in the upstream chamber (25) pushes the small disc (30) against the pierced diaphragm (27) .  8. Tap according to claim 1, characterized in that the connection part (SR) for making the connection to the gas supply pipe coming from the gas distribution network comprises a seat with two jaws (36, 37) and a spout (32a) penetrating into said supply pipe (10), the inner conduit of this spout leading to the upstream chamber (25) of the part comprising the safety valve.  9. Valve according to one of the preceding claims, characterized in that the series of conduits defining a path for the gas flow from the nozzle (32a) to which the gas supply pipe (10) is connected to the point for connection to the burner comprises a first conduit (32) between the spout (32a) connecting to the supply pipe (10) and the upstream chamber (25) of the safety part, a second conduit (33) between the downstream chamber (26) of the safety part and the lower chamber (11) of the tap part (R), as well as a third conduit (21) between the flared cavity (11a) of the tap part and the connection point to the burner.  10. Valve according to claim 9, characterized in that the path of the gas flow passes through the following components: the spout (32a) for connection to the gas supply pipe (10); the first conduit (32); the upstream chamber (25); the drilled diaphragm (270 and the downstream chamber (26) of the safety part valve (S); the second conduit (33); the lower chamber (11); the hole (17, 17a) for maximum or minimum flow gas which is formed in the conical member (12); and the hole in the flared wall (lla) of the tap part (R); and, finally, the third conduit (21).  11. Tap according to claim 1, characterized in that the kinematic chain for manual actuation (opening action) of the safety valve comprises a transverse pin (20) fixed to the rod (13) of the button, this pin being able to rest on the head (22) of a pin (23) assembled so as to be able to slide vertically in the body (16) of the tap part (R) in a direction parallel to the axis of the rod of the button , a first tongue (39) cooperating with the lower end of the spindle (23) sliding vertically, this tongue (39) being fixed to one end of a small shaft (40) so as to rotate with the latter which is mounted transversely and rotatably in the base of the tap, and a second tongue (41) fixed to the other end of this small shaft (40) so as to rotate with it and to cooperate with the thin rod (34) for manual actuation of the safety valve.  12. Tap according to claim 11, characterized in that the transverse pin (20) is small and passes through a slot in the envelope of the tap part (R), this slot defining the stop positions for rotation of the button (14 ).  13. Tap according to claim 11, characterized in that the position in which the small spindle (20) is above the head (22) of the spindle (23) mounted with vertical sliding is an intermediate position between the stop positions of rotation of the rod (13) of the button to which this small pin (20) is fixed.