FR2606854A1 - INTEGRATED SAFETY GAS INLET VALVE FOR HOT WATER PRODUCTION APPARATUS WITHOUT PERMANENT PILOT - Google Patents

Abstract

THE INVENTION RELATES TO A GAS INLET VALVE WITH INTEGRATED SAFETY. ACCORDING TO THE INVENTION LEDIT VALVE INCLUDING A ROTARY ARMING BUTTON 1 AND A FLASHING DIAPHRAGM MECHANISM 8, 4 LINKED TO A BULB AND RESPONDING TO A TEMPERATURE RISE OF THE COMBUSTION PRODUCTS INCLUDES A CAM 2 ROTATING AROUND THE AXEAA '' ACTION OF THE BUTTON WHICH COOPERATES WITH THE CONTROL ROD 7, 21 OF THE GAS INTAKE VALVE 6 AND WHICH IS ALSO MOVABLE IN TRANSLATION ON THIS AXIS AA UNDER THE ACTION OF THE BLOCKING DIAPHRAGM MECHANISM 8 TO EXHAUST THE ROD 7 CONTROL OF THE VALVE AND SECURE THE APPLIANCE. APPLICATION TO HOT WATER PRODUCTION EQUIPMENT WITHOUT PERMANENT PILOT.

Description

The invention relates to a gas inlet valve which incorporates a device

  safety device for stopping a hot water production device of the water heater or gas-bath heater type in the event of a draft anomaly, in particular in the flue gas discharge duct, and applies

  especially to appliances without permanent night light.

  It is known that when a gas appliance of a certain power is connected to a flue, it is considered that its operation takes place under normal conditions when all of the combustion products are discharged into this duct. In some cases, because the natural draft is insufficient, an extractor is placed in the duct or in a collection duct of the flue gases of several

  appliances; the installation is then called mechanical ventilation

controlled territory (V.M.C.).

  In any case, whatever the solution adopted, natural draft or VMC., It is necessary that a safety device can react to any anomaly, due for example to a bad draft, to a repression, to an obstruction of the

  led or an extractor failure, an anomaly which causes the

  flow of combustion products in the room.

  There are many security features that are suitable for responding to these anomalies. In some cases the electrical contact of a thermosensitive element placed at the end of the draft hood opens at a certain temperature and closes a gas inlet solenoid valve. In other systems a thermosensitive bulb acts on an expandable membrane which itself cuts the gas inlet to the night light of the appliance or

  acts directly on its thermoelectric safety mechanism

  only to put the device safe. For other

  In the case of a small tube, an abnormality of draft in a duct is detected.

  air and gas pre-mixing pilot and then

safe.

  There is, however, a category of devices for the production of hot water by the gas to which these various devices can not be applied. These are the water heaters and hot-water heaters operating without a permanent pilot light which do not use thermoelectric safety system and therefore can not be used in response to a

  anomaly in the exhaust duct of combustion products.

  To solve this problem, the solution consists in making the gas inlet valve of the apparatus act positively, a safety mechanism using a lever for triggering the cocking member of said valve and a movable member. controlled by a thermosensitive element arranged in good position to react for example of an elevation

  temperature in a flue gas exhaust duct.

  This security mechanism as described in French Patent 1,574,526 in the name of the Applicant

  has a leverage arming mechanism of the

  gas mission to the device that can be snapped on a

  trigger lever whose pivoting causes disarmament

  and closing of said Jaz intake valve under the effect of its return spring and which has an element

  thermally sensitive reaction in a manner known per se

  temperature of the exhaust of the combustion products, which acts positively on said trigger lever of the cocking mechanism by means of an expandable bellows whose displacement causes the

  pivoting a branch of said lever and stopping the

  mera. Apart from the difficulties of realization that may

  ter this mechanisne taking into account the various parts to achieve and assemble, it has the disadvantage, although being positive security that is to say reacting in the direction

  shutdown of the appliance in the event of failure of the said

  not to provide security in case of false

  by a user. Indeed the disarming of the gas inlet valve can always be blocked by the user if it maintains a pressure on the

  arming lever or if he immobilizes it by any means

  than; in this case the gas remains admitted in the device which

  whatever the operating conditions.

  This is why the Applicant has developed a new gas intake valve simpler realization and operation that avoids the disadvantages of the known mechanisms and has a total safety.

  According to the invention, said faucet comprising a

  your rotating armament and a metastable mechanism of the kind with

  connected to a bulb and reacting to a rise in tempera-

  The combustion products have a cam mounted rotatably about its axis under the action of said button, which cooperates with the control rod of the valve.

  gas intake and which is also movable in trans-

  on said axis under the action of the blister membrane mechanism to escape the control rod of the

  flapper and put the device in safety.

  According to a main characteristic of

  the invention, the cam has a decent section

  arranged between a cylindrical section of small diameter

  and a cylindrical section of larger diameter, both centered on its axis, a generatrix of the eccentric section extending a generatrix of the small diameter section, another generatrix diametrically

  opposite of this decentralized section prolonging a genera-

  trice of the larger diameter section.

  According to another characteristic of the in-

  vention, the axis of operation of the control rod of the

  pet is resting against the edge of the intermediate cylindrical section of the cam and protrudes above the section

  cylindrical of smaller diameter.

  Special features and others

  advantages of the invention will now emerge from the

  following a non-limitative example of how

  and with reference to the accompanying drawings, which show: FIG. 1 is a diagrammatic sectional view of the valve; FIG. 2 is a perspective view of the cam

shown in Figure 1.

  The body 17 of the gas inlet valve contains a valve 6 putting in communication a conduit

  gas inlet 18 and the conduit 19 to the starting

  mera. A plug 20 closing the body 17 is crossed by

  sealingly by the operating rod 21 of the valve 6 normal-

  The body 17 of the valve is secured to a control box 22, one of which

  tubular portion 15 is aligned with the stem 21 of the valve.

  This tubular portion encloses an axis 7 which abuts against the end of the rod 21, which opens to the other

  side in the housing 22 and bears on a cam 2.

  It can rotate around its axis AA 'and has the form

  shown in Figure 2. It has a cylindrical section

  23 of small diameter, another cylindrical section 24 of larger diameter both centered on the axis AA ',

  and interposed between the two, a cylindrical section 25 de-

  centred which a generator extends the generator section 23 of

  small diameter, and another generator diametrically oppo-

  The first extension extends the generatrix of section 24 of large diameter. In the rest position the axis 7 is in abutment against the edge of the intermediate cylindrical section 25, overflowing even above the cylindrical section 23 of smaller diameter. The cylindrical section 23 of the cam 2 is provided with a recess 26 with two inner flats for receiving without friction a maneuvering needle 27 integral with a rotary control knob 1. This can occupy two positions between the rest position shown and an arming position where it has rotated counter-clockwise,

  against the restoring force of a torrent spring.

  12. An associated ball retainer 14

  a spring 16, integrated in a button 1 is now used to

  the latter in one or other of its two positions by means of two appropriate housings (28, 28 ') provided for in

case 22.

  The other cylindrical section 24 of the cam 2 has a threaded inner orifice 29 to which is fixed a set screw 9. This screw is coaxial with a fixed rod 3 on which it can slide. The rod carries an end stop 30 for a spring 13 bearing against the

screw 9.

  The valve body 17 also supports a security assembly known per se consisting of a metallic blister membrane8 capable of reacting in the direction of a transition to the convex form shown in dotted lines

  during the heating of a bulb placed in the appropriate position

  for example in a VMC sheath and connected to the mem-

  brane through the conduit 5. The membrane 8 is in abutment against the end of a lever 4 pivoting about an axis 10 and

  whose other end abuts the screw 9.

  The fail-safe valve, thus de-

  crit, works as follows.

  Figure 1 shows the elements in posi-

  rest when the valve 6 is closed on its seat. The UTI

  the user, when he wants to arm the apparatus, turns the knob 1 counterclockwise until the ball 14 is engaged in the other housing 28 'of the

  In the course of this movement the maneuvering needle

  vre 27 engaged in the recess 26 rotated so

  cam 2. The shaft 7 bears on the cylindrical section

  drique décentrée 25 of said cam and thrust by it rises in the tubular portion 15, and exerts a thrust on the rod 21 in the direction of the opening of the valve 6 to

  against the restoring force of the spring 11 '. The gas

  From conduit 18 is therefore admitted to the device through the conduit 19. If, during a drawing, the evacuation of the combustion products is carried out normally, the membrane 8 and the lever 4 occupy the position shown. Axis 7 exerting pressure on the portion 25 of the cam 2, normally at the axis AA '(FIG. 2), the button remains in the armed position,

  helped by the snap of the ball 14 in the recess-

  28 'under the action of the small spring 16.

  If there is an anomaly in the

  cuation of the products of combustion of the apparatus, characterized

  by heating the bulb, the temperature rise trans-

  put by the conduit 5 will pass abruptly the membrane 8 in the convex position shown in dashed lines. The lever 4 then pivots around the axis 10 and its opposite end exerts a pressure on the screw 9, oriented towards the drawing right. The screw 9 and the cam 2 secured to it by the threaded connection 29 then deviate to the right by sliding on the rod 3 against the force of the spring 13 and away from the operating knob 1. This distance is made possible by the fact that the needle 27 of the button is inserted with clearance into the orifice 26 of the cam '. Axis 7

  jogging on section 25 of the cam will

  per it and fall back on the cylindrical section 23

  under the pressure of spring II which will also close the

  fart 6, interrupting the admission of the gas to the apparatus.

  After this safety, as the bulb has not cooled and the membrane 8 has not returned to its original shape, the cam 2 remains offset from the axis 7 prohibiting the rearming of the device. This means that, even if the user, having brought the button i back to its starting position, wanted to arm it again immediately, its rotation would have no effect on the axis 7 and the flap 6

  could under no circumstances be reopened.

  But as soon as the bulb has cooled and the membrane 8 has returned to its shape, the screw 9 is no longer

  subjected to the pressure of the lever 4, the spring 13 can

  place the cam in its initial position. If, during this movement, the button had remained turned in the armed position, it is sufficient for the user to return the button 1 to the position of

  start then rearm to return to the position of

  normal operation. So we see that this security can act at any time during the opening maneuver and what

  whatever the position in rotation of the button 1.

  The device is positive safety because in case of leakage or failure of the bulb, the blister membrane immediately takes the convex shape for which there is action on the lever 4 and put the device safe.

  It will be noted that the device according to the invention

  tion can not operate with the blistering blade described above, but also with a bellows expansion for example coupled to a buckling blade or with any expandable system whose sealing and metastability functions are not provided by the

same element.

  Finally and independently of this security, the user can stop the device by turning the knob 1 in the direction of a clockwise which

  returns the cam 2 to the position of FIG.

  which the axis 7 went down and the valve 6 closed again

under the action of spring 11.

  The spacing between the screw 9 and the cam 2 can be adjusted, these two parts cooperating by a threaded connection. It is thus possible to adjust the "overhang" of the axis 7 on the part 25 of the cam as a function of the deflection of the

arm 4.

Claims (7)

  I.- Intake gas safety valve   tégrée for hot water production unit without permanent pilot, allowing the closing of the inlet valve in case of anomaly in the evacuation of its combustion products.   tion, comprising a rotating arming knob that operates a cam   on the stem of the valve and a metastebl mechanism of the midembrane type   blister-related bulb responding to a rise in temperature   ture of said combustion products, which mechanism is capable of causing the closure of the valve, characterized in that the cam 0 rotatably mounted about its axis AA 'under the action of the button (1) and cooperating with the control rod ( 7,21) of the valve (6) is also displaceable in translation on said axis under the action of the mechanism (4,9) of the blister membrane type (8), to make it escape from the   valve control rod and secure the device.   2.- Tap according to claim 1, characterized in that the cam (2) has a   an off-center section (25) disposed between a cylindrical section   small diameter (23) and a cylindrical section (24)   of larger diameter, both centered on the axis AA '.   3.- Tap according to claim 2 characterized in that a generatrix of the off-center section (25) extends a generatrix section (23)   small diameter, and another diameter generatrix-   opposite side of this decentralized section prolongs a general   section (24) of larger diameter.   4.- Tap according to claims 1, 2   and 3 characterized in that the axis (7) for operating the valve control rod (21) (6) bears against the edge of the intermediate section (25)   cam (2) and protrudes above the cylindrical section. than (23) smaller diameter.   5.- Faucet according to claim 1 and   2 characterized by the fact that the membrane mechanism closes   quante (8) acts by means of a lever (4) on a set screw (9) integral with the cam (2) the screw-cam assembly slidable on a fixed rod (3) according to axis AA '.   6. Tap according to claim 5,   characterized by the fact that the lever (4) acts on the screw (9) in   the direction of a distance from the cam (2) of its button   (1) against the return force of a spring (13).   7.- Faucet according to claim 5,   characterized in that the spacing between the screw (9) and the cam (2) is adjustable due to the threaded connection that the makes solidarity.