JP2011226673A - Rotary gas valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary gas valve device having an electromagnetic safety valve and a heat control valve with a simple structure, wherein operativity is excellent and a burner is prevented from being accidentally ignited.SOLUTION: The rotary gas valve device includes a lock mechanism 9 for releasing a locked state at an extinction position by a push-on operation with an operation shaft 6, a first switch 10which turns on during a turning initial stage from the extinction position of the operation shaft 6 to a high heat position, and a second switch 10which turns on at a turning termination stage, and an electronic control board 12. The electronic control board 12 is triggered when the first switch 10is turned on to start forced hold control on the electromagnetic safety valve 3. Further, when the second switch 10is turned on, it starts ignition control, and when an electromotive voltage of a thermocouple B3 for detecting a flame rises to a predetermined level, it stops the ignition control, and then exerts control to close the electromagnetic safety valve 3 at burner flame extinction.

Description

  The present invention relates to a rotary gas valve device in which an electromagnetic safety valve and a rotatable thermal power control valve for adjusting the thermal power of a burner are housed in a valve casing.

  Conventionally, as this type of gas valve device, an operation shaft that can be rotated from an extinguishing position in which the thermal power control valve is fully closed to an ignition position that slightly exceeds the high fire position in which the thermal power control valve is fully opened, and an electromagnetic safety valve A push rod that can be moved back and forth, and a push rod that moves forward in conjunction with the rotation of the operation shaft from the fire extinguishing position to the ignition position, presses and opens the electromagnetic safety valve, and releases the rotational force for the operation shaft at the ignition position. A cam mechanism that retreats the push rod to release the pressure of the electromagnetic safety valve and returns the operation shaft from the ignition position to the high fire position, and an ignition switch that is turned on by turning the operation shaft to the ignition position. Are known (for example, see Patent Document 1).

  In this configuration, the electromagnetic safety valve is pressed and opened via the pressing rod by the cam mechanism by the rotation of the operation shaft from the fire extinguishing position to the ignition position, and the igniter is activated when the ignition switch is turned on at the ignition position. The burner is ignited. When the rotational force with respect to the operating shaft is released after ignition, the operating shaft is returned to the high fire position by the action of the cam mechanism, the ignition switch is turned off, and the operation of the igniter is stopped. In addition, the electromagnetic safety valve is released by releasing the rotational force with respect to the operating shaft, but the electromotive force of the flame detection thermocouple attached to the burner is supplied to the electromagnetic safety valve, and the electromagnetic safety valve is opened. Retained. And if the electromotive force of a thermocouple falls by the misfire of a burner, an electromagnetic safety valve will close and discharge | release of raw gas will be prevented.

  By the way, after ignition, it takes some time until an electromotive force sufficient to open and hold the electromagnetic safety valve from the thermocouple is generated, and it is necessary to continue pressing the electromagnetic safety valve during that time. For this reason, in the above conventional example, the rotational force with respect to the operation shaft cannot be released for a while after ignition, and the operability is deteriorated.

  In addition, the conventional example requires a cam mechanism that moves the pressing rod back and forth in conjunction with the rotation of the operation shaft and also returns the operation shaft from the ignition position to the high fire position. Become. Furthermore, since the burner can be ignited only by rotating the operation shaft, the user's clothes are caught on the operation knob at the shaft end of the operation shaft, the operation shaft is rotated, and the burner is ignited carelessly. There is also.

Japanese Patent Laid-Open No. 9-159053

  In view of the above points, an object of the present invention is to provide a rotary gas valve device having a simple structure that is excellent in operability and can prevent a burner from being ignited carelessly. .

  In order to solve the above-mentioned problems, the present invention is a rotary gas valve device in which an electromagnetic safety valve and a rotatable thermal power control valve that adjusts the thermal power of a burner are housed in a valve casing. An operation shaft that can be freely rotated from a fire extinguishing position in which the valve is fully closed to a high fire position in which the thermal power control valve is fully open, a lock means that locks the operating shaft in the fire extinguishing position, and an operation shaft that is operated by pushing the operation shaft. A push rod that is pushed forward by an electromagnetic safety valve, a first switch that is turned on in the initial stage of rotation of the operation shaft from the fire extinguishing position to the high fire position, and a final stage of rotation of the operation shaft from the fire extinguishing position to the high fire position A second switch that is turned on and an electronic control board, and when the operating shaft is pushed in the fire extinguishing position, the lock by the locking means is released and the electromagnetic safety valve is pushed open through the pushing rod, Electronic control board The forced hold that is activated when the first switch is turned on and forcibly holds the electromagnetic safety valve in an open state by energizing the electromagnetic safety valve until a predetermined first set time elapses after the first switch is turned on. Control, ignition control that activates the igniter when the second switch is turned on to ignite the burner, and when the electromotive voltage of the flame detection thermocouple attached to the burner rises to a predetermined flame detection level, Stops ignition control and energizes the electromagnetic safety valve following forced hold control. When the electromotive voltage of the thermocouple falls below the flame detection level due to a burner misfire, energization of the electromagnetic safety valve is stopped and the electromagnetic safety valve is closed. It is characterized by performing safety control to be valved.

  According to the present invention, the operation shaft cannot be rotated unless the operation shaft is pushed at the fire extinguishing position to release the lock by the lock means, and the burner can be prevented from being ignited accidentally. Further, when the operation shaft is pushed in the fire extinguishing position, the electromagnetic safety valve is pushed open, and when the first switch is turned on at the initial stage of rotation from the fire extinguishing position to the strong fire position, the forced hold control is started. The Therefore, even if the operating shaft is rotated without being pushed to the high fire position after that, and even when the operating shaft is rotated to the high fire position and the turning force for the operating shaft is released immediately, the electromagnetic safety valve is in the open state. Therefore, it is excellent in operability.

  Further, when the second switch is turned on by turning to the strong fire position, the burner is ignited by ignition control, and then the operation of the igniter is stopped when the electromotive voltage of the thermocouple rises to a predetermined flame detection level. . Therefore, in order to stop the operation of the igniter, there is no need to provide a mechanism for returning the operation shaft from the strong fire position to the position where the second switch is turned off. Here, in the present invention, the locking means is provided, but the structure is sufficient, for example, to form a hole portion that engages with a rotation-preventing projection formed on the operation shaft on the lid plate through which the operation shaft is inserted. The structure of the gas valve device is simplified as compared with the conventional example having a complicated cam mechanism that moves the pressing rod back and forth in conjunction with the rotation of the operation shaft and returns the operation shaft.

  By the way, even if the burner is ignited, it takes some time for the electromotive voltage of the thermocouple to rise to the flame detection level, and before that, the forced hold control is terminated and the electromagnetic safety valve is not closed. In addition, the first set time is set relatively long. Then, when the forced hold control is started when the first switch is turned on at the initial turning stage of the operation shaft from the fire extinguishing position to the high fire position as in the present invention, the second switch is turned on. If it is stopped before starting, a large amount of raw gas is released until the first set time elapses without ignition control.

  Therefore, the electronic control board performs control to stop the forced hold control when the second switch is not turned on until the second set time set shorter than the first set time elapses from the time when the first switch is turned on. Is desirable. According to this, it is possible to reduce the amount of raw gas released when the rotation operation of the operation shaft is stopped halfway.

  The above-described improvement in operability and simplification of the structure can be achieved by using an electronic control board. Here, even when the temperature detected by the temperature sensor that detects the temperature of the object to be heated attached to the burner rises to the specified overheat temperature, the electronic safety board stops energization and closes the electromagnetic safety valve. If it is configured to perform the safety control to be valved, it is possible to improve operability and simplify the structure using an electronic control board essential for preventing overheating of the object to be heated, which is extremely rational.

Sectional drawing of the rotary gas valve apparatus of embodiment of this invention. The perspective view of the decomposition | disassembly state of the rotary gas valve apparatus of FIG. 1A is a cross-sectional view of the operation shaft cut along the line III-III in FIG. 1 at a fire extinguishing position, FIG. Sectional drawing in the rotation final stage from a fire extinguishing position to a strong fire position, (d) Sectional drawing in the strong fire position of an operating shaft. The flowchart which shows the control content by an electronic control infrastructure.

  Referring to FIG. 1, reference numeral 1 denotes a rotary gas valve device according to an embodiment of the present invention that controls gas supply to a burner B provided in a gas appliance such as a gas stove. The burner B is provided with an ignition electrode B2 that performs spark discharge by the operation of the igniter B1, a thermocouple B3 that detects the flame of the burner B, and a temperature sensor B4 that detects the temperature of the object to be heated.

  The rotary gas valve device 1 includes a longitudinally extending valve casing 2, an electromagnetic safety valve 3 accommodated in the rear end portion of the valve casing 2, and a rotatable thermal power control valve 4 accommodated in an intermediate portion of the valve casing 2. And. In the valve casing 2, a gas inlet 2 a communicating with the storage space of the electromagnetic safety valve 3, a gas outlet 2 b communicating with the storage space of the thermal power control valve 4, a storage space of the electromagnetic safety valve 3 and a storage of the thermal power control valve 4 A valve hole 2c between the space is formed.

  The electromagnetic safety valve 3 includes a valve body 3b urged by a spring 3a to a closed position for closing the valve hole 2c, a magnetic piece 3d attached to a rear end of the valve shaft 3c extending backward from the valve body 3b, and a magnetic piece 3d. And an electromagnet 3e facing the. The valve body 3b is pushed by a later-described pressing rod 8 to a position where the magnetic piece 3d contacts the electromagnet 3e. In this state, the electromagnet 3e is energized, so that the electromagnetic safety valve 3 is attracted and held.

  The thermal power control valve 4 is configured by a cylindrical body having an outer peripheral surface as a tapered surface. The polymerization opening degree of the opening 4a (see FIG. 2) opened on the outer peripheral surface of the thermal power control valve 4 and the gas outlet 2b changes as the thermal power control valve 4 rotates, and the gas supplied to the burner B The amount, ie the heating power of burner B, is adjusted.

  An operation shaft 6 inserted into the valve casing 2 through a cover plate 5 attached to the front end of the valve casing 2 and a connector 7 housed in the front end portion of the valve casing 2 are provided. An operation knob 6 a is attached to the front end portion of the operation shaft 6. As shown in FIG. 2, a hole 7 a having a non-circular cross section is formed at the rear end of the connector 7, and the rear end of the operation shaft 6 having a non-circular cross section is fitted therein. A claw piece 7b that protrudes in the front-rear direction dividing groove 4b formed at the front end is projected. The thermal power control valve 4 is rotated via the connector 7 by the rotation of the operation shaft 6. The thermal power control valve 4 is urged rearward by a spring 4c that is contracted between the connector 7 and a sealing property between the outer peripheral surface of the flow control valve 4 and the inner peripheral surface of the valve casing 2 is ensured. Is done.

  In addition, a pair of protrusions 7 c are formed on the outer peripheral surface of the connector 7 with a point-symmetrical positional relationship, and a pair of protrusions 2 d are also formed on the inner peripheral surface of the front end portion of the valve casing 2 with a point-symmetrical positional relationship. Yes. Then, the rotation range of the connector 7, that is, the rotation range of the operating shaft 6, is the fire extinguishing position where the heating power control valve 4 is fully closed by the contact of the protrusions 2d and 7c (FIG. 3A). ) And a high fire position (position shown in FIG. 3 (d)) in which the thermal power control valve 4 is fully opened (for example, an angle range of 110 °).

  Further, a longitudinal pressing rod 8 is provided in the front-rear direction penetrating the thermal power control valve 4. The pressing rod 8 is in contact with the rear end of the operating shaft 6 by the biasing force of the spring 8a. When the operating shaft 6 is pushed, the pressing rod 8 is pushed by the operating shaft 6 and moves forward to the electromagnetic safety valve 3 side. The pressing rod 8 comes into contact with the valve body 3b of the electromagnetic safety valve 3 so that the electromagnetic safety valve 3 The valve is pressed and opened. An O-ring 4 d that prevents gas from leaking forward through a gap between the pressure rod 8 is mounted in the thermal power control valve 4. Further, a flange portion 6b that abuts the back surface of the cover plate 5 is formed in the intermediate portion of the operation shaft 6 so that the biasing force of the spring 8a acting on the operation shaft 6 can be received by the cover plate 5 through the flange portion 6b. I have to.

  Further, a lock means 9 for locking the operation shaft 6 in the fire extinguishing position is provided. The lock means 9 is formed in a hole 9a extending outward from two places around the insertion hole 5a for the operation shaft 6 formed in the cover plate 5 and a hole 9a protruding from the front surface of the flange portion 6b of the operation shaft 6. And corresponding projections 9b. Then, the projection 9b engages with the hole 9a at the fire extinguishing position of the operation shaft 6, the operation shaft 6 is locked at the fire extinguishing position, and when the operation shaft 6 is pushed, the projection 9b comes out of the hole 9a and is locked. Is released.

  When the pushing operation is released with the operation shaft 6 rotated from the fire extinguishing position, the projection 9b comes into contact with the back surface of the cover plate 5, and the position of the pressing rod 8 is behind the position of the backward stroke end shown in FIG. Sneak away. In this state, if the rear end portion of the pressing rod 8 protrudes rearward from the valve hole 2c, the electromagnetic safety valve 3 cannot be closed. Therefore, the protruding height of the protrusion 9b is set so that the rear end portion of the pressing rod 8 does not protrude rearward from the valve hole 2c in a state where the protrusion 9b is in contact with the back surface of the lid plate 5.

  A micro switch 10 is attached to the cover plate 5, and a cylindrical cam 11 that is in contact with the operation lever 10 a of the micro switch 10 is attached to the operation shaft 6 so as to rotate integrally with the operation shaft 6. In order to prevent the cylindrical cam 11 from coming off, a presser plate 5 b that contacts the front end of the cylindrical cam 11 is attached to the lid plate 5.

Microswitch 10 is intended first switch 10 ₁ and the second switch 10 ₂ and the two-contact type having a built-in, the cylindrical cam 11, the first cam projection 11a and than this of the large diameter second Kamu突A portion 11b is formed. Then, at the initial stage of rotation of the operation shaft 6 from the fire extinguishing position to the high fire position, for example, when the operating shaft 6 is rotated by 20 ° from the fire extinguishing position, the operating lever 10a is moved by the first cam projection 11a as shown in FIG. pushed in, the first switch 10 ₁ is turned on, turning final stage of the high heat position from the extinguishing position of the operating shaft 6, for example, where the 95 ° rotated from the extinguishing position, the operation lever 10a and the second cam projection It is further pushed by 11b, the second switch 10 ₂ is to be turned on.

Referring to FIG. 1, the first switch 10 ₁ is intervening to a circuit for introducing power from the power source 13 consisting of battery to the electronic control board 12 comprising a microcomputer. The second switch 10 ₂ is intervention in the circuit connecting the grounding resistor R and the positive electrode of the power source 13. Then, and the voltage between the second switch 10 ₂ and the ground resistor R as input to the electronic control board 12 determines the second switch 10 ₂ on and off at high and low of the voltage. In addition, an ignition switch 14 is interposed in a circuit for supplying power from the power source 13 to the igniter B1, and a safety valve switch 15 is interposed in a circuit for supplying power from the power source 13 to the electromagnet 3c of the electromagnetic safety valve 3. The ignition switch 14 and the safety valve switch 15 are controlled to be opened and closed by the electronic control board 12. The electronic control board 12 receives an electromotive voltage of the thermocouple B3 and a detection signal of the temperature sensor B4.

Hereinafter, operation of the operation shaft 6 and control by the electronic control board 12 will be described with reference to FIG. First, the operating shaft 6 is pushed at the fire extinguishing position to release the lock by the locking means 9 and the electromagnetic safety valve 3 is pressed and opened via the pressing rod 8 (STEP 1). When rotating the operating shaft 6 from the extinguishing position, first, the first switch 10 ₁ is turned on, the electronic control board 12 is started at power-on from a power source 13 (STEP2). When the electronic control board 12 is activated, first, the safety valve switch 15 is turned on, the electromagnet 3e of the electromagnetic safety valve 3 is energized, and the electromagnetic safety valve 3 that has been pressed open is forcibly held open. (STEP 3).

Next, the second set time the elapsed time TM from the first turn-on time switch 10 ₁ is set shorter than the first set time YTM1 described later YTM2 (e.g., 3 seconds) to determine whether it has reached (STEP4), if TM <YTM2, the second switch 10 ₂ is determined not to have been turned on (STEP5). Then, from the first turn-on time switches 10 ₁ to the second set time YTM2 has elapsed, when the second switch 10 ₂ is not turned on, and turns off the safety valve switch 15, to stop the forced hold control (STEP6) .

On the other hand, before the first turn-on time switches 10 ₁ second set time YTM2 has elapsed, when the operating shaft 6 is the second switch 10 ₂ is turned on is rotated to near high heat position, the ignition switch 14 The ignition control is performed so that the igniter B1 is energized and the burner B is ignited by spark discharge at the ignition electrode B2 (STEP 7).

Then, the elapsed time TM from the first turn-on time switch 10 ₁ is first set time YTM1 (e.g., 10 seconds) to determine whether reached (STEP 8), if TM <YTM1, thermocouple It is determined whether or not the electromotive voltage VTC of B3 has increased to a predetermined flame detection level YVF (for example, 2.5 mV) (STEP 9). Then, from the first turn-on time switches 10 ₁ to the first set time YTM1 has elapsed, when the result is not as VTC ≧ YVF serves to stop the ignition control of the ignition switch 14 is turned off, the safety valve switch 15 The forced hold control is stopped by turning it off (STEP 10).

On the other hand, before the first turn-on time switches 10 ₁ first set time YTM1 has elapsed, when it becomes VTC ≧ YVF is an ignition switch 14 turns off to stop the ignition control (STEP 11). In this case, the safety valve switch 15 is maintained in the ON state, and energization to the electromagnetic safety valve 3 is continued following the forced hold control. Next, it is determined whether or not the electromotive voltage VTC of the thermocouple B3 is lower than the flame detection level YVF (STEP 12), and whether or not the detected temperature TH of the temperature sensor B4 has increased to a predetermined overheat temperature YTH. (STEP 13) When VTC <YVF, or TH ≧ YTH, the safety valve switch 15 is turned off to stop energization of the electromagnetic safety valve 3 and to perform safety control to close the electromagnetic safety valve 3 ( (STEP 14).

As described above, according to the present embodiment, even when the user's clothes are caught on the operation knob 6a and the turning force acts on the operation shaft 6, the operation shaft 6 is pushed and operated in the fire extinguishing position. Unless the lock is released, the operation shaft 6 does not rotate, and the burner B can be prevented from being ignited accidentally. Further, when pressed the operating shaft 6 in extinguishing position, the electromagnetic safety valve 3 is pressed open, when the first switch 10 ₁ is turned on by turning the initial stage to the high heat position from the extinguishing position, forcing the hold Control begins. Therefore, even if the operating shaft 6 is rotated without being pushed to the high fire position after that, and the rotational force for the operating shaft 6 is immediately released when the operating shaft 6 is rotated to the high fire position, the electromagnetic safety valve 3 Is held in an open state, and is excellent in operability.

Further, when the second switch 10 ₂ is turned on by the rotation in the high heat position, is ignited burner B in the ignition control, then, when the electromotive voltage VTC of the thermocouple B3 increases the flame detection level YVF, ignition switch 14 Is turned off, and the operation of the igniter B1 is stopped. Therefore, in order to stop the operation of the igniter B1, operating shaft 6 second switch 10 ₂ from high heat position it is not necessary to provide a mechanism for rotating the return to a position that is off. Here, in the present embodiment, the locking means 9 is provided, but the structure thereof is a hole portion 9a in which a rotation stop projection 9b formed on the operation shaft 6 engages with the lid plate 5 through which the operation shaft 6 is inserted. It is sufficient to form the gas valve device as compared to the conventional example, which has a complicated cam mechanism that advances and retracts the pressing rod in conjunction with the rotation of the operation shaft and returns the operation shaft. Is simplified.

  The above-described improvement in operability and simplification of the structure can be achieved by using the electronic control board 12. Here, the electronic control board 12 is indispensable for attaching the temperature sensor B4 to the burner B to prevent overheating of the object to be heated. Simplification is extremely reasonable.

By the way, even if the burner B is ignited, it takes some time for the electromotive voltage VTC of the thermocouple B3 to rise to the flame detection level YVF. Before that, the forced hold control ends and the electromagnetic safety valve 3 is closed. In order to prevent this, the first set time YTM1 is set to a long value, for example, 10 seconds. In this state, if you've stopped rotational operation of the control shaft 6 before the first switch 10 ₁ is turned on by forced hold control is ₂ second switch 10 from the start with is turned on, the ignition control is performed A large amount of raw gas is released until the first set time YTM1 elapses.

However, in the present embodiment, when the second switch 10 ₂ until the second set time YTM2 be shorter than the first set time YTM1 from the first turn-on time switch 10 ₁ has elapsed is not turned on, the forced hold control The operation is stopped and the electromagnetic safety valve 3 is closed. Therefore, it is possible to reduce the amount of raw gas released when the rotation operation of the operation shaft 6 is stopped halfway.

As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to this. For example, in the above embodiment, the first switch 10 ₁ and although the second switch 10 ₂ is constituted by a micro-switch 10 of the two-contact, and micro-switches of the first switch 10 for ₁ of the second switch 10 for ₂ A micro switch may be provided separately. Moreover, in the said embodiment, although the operating shaft 6 and the press rod 8 are made into a different body, both 6 and 8 can also be integrated.

B ... burner, B1 ... igniter, B3 ... thermocouple, B4 ... temperature sensor, 1 ... rotary gas valve device, 2 ... valve casing, 3 ... electromagnetic safety valve, 4 ... thermal power control valve, 6 ... operating shaft, 8 ... press Rod, 9 ... Locking means, 10 ₁ ... First switch, 10 ₂ ... Second switch, 12 ... Electronic control board.

Claims (3)

A rotary gas valve device in which an electromagnetic safety valve and a rotatable thermal power control valve for adjusting the thermal power of a burner are housed in a valve casing,
An operation shaft that can be freely rotated from a fire extinguishing position where the thermal power control valve is fully closed to a high fire position where the thermal power control valve is fully opened, a locking means for locking the operating shaft to the fire extinguishing position, and a push operation of the operating shaft A push rod that is pushed by the operating shaft and moves forward to the electromagnetic safety valve side, a first switch that is turned on at the initial stage of rotation of the operating shaft from the fire-extinguishing position to the high-fire position, and rotation of the operating shaft from the fire-extinguishing position to the high-fire position A second switch that is turned on at the final stage, and an electronic control board,
When the operating shaft is pushed in the fire extinguishing position, the lock by the locking means is released, and the electromagnetic safety valve is pressed open through the pressing rod,
The electronic control board is activated when the first switch is turned on, and energizes the electromagnetic safety valve until the predetermined first set time elapses from the time when the first switch is turned on to forcibly open the electromagnetic safety valve. Forced hold control to hold, ignition control to activate the igniter when the second switch is turned on to ignite the burner, and the electromotive voltage of the thermocouple for detecting the flame attached to the burner rises to a predetermined flame detection level The ignition control is stopped and the electromagnetic safety valve is energized following the forced hold control.When the electromotive voltage of the thermocouple falls below the flame detection level due to burner misfire, the energization of the electromagnetic safety valve is stopped. A rotary gas valve device that performs safety control for closing an electromagnetic safety valve.   The electronic control board is configured to stop the forced hold control when the second switch is not turned on until a second set time set to be shorter than the first set time elapses after the first switch is turned on. The rotary gas valve device according to claim 1, wherein:   The electronic control board stops energization of the electromagnetic safety valve and closes the electromagnetic safety valve even when the temperature detected by a temperature sensor for detecting the temperature of an object to be heated attached to the burner rises to a predetermined overheating temperature. The rotary gas valve device according to claim 1 or 2, wherein safety control is performed.

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