JP2008267639A - Gas combustion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas combustion device capable of allowing a proportional valve to normally operate by performing the fixation releasing operation of the proportional valve when a probability of the fixation of the proportional valve exists, regardless of a combustion stop time. <P>SOLUTION: A control portion 4 of the gas combustion device 1 closes opening and closing valves 6, 7 and the proportional valve 5 (S8), then temporarily opens the proportional valve 5 with a maximum opening, and then closes the valve (S9) when a thermocouple 14 detects defective ignition or fire extinction on the way of a combustor 11, to prevent the fixation of the proportional valve 5. Accordingly, the proportional valve 5 can be allowed to normally operate even if a probability of the fixation of the proportional valve 5 exists, regardless of the combustion stop time of the combustor 11. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention belongs to a technical field of a gas combustion device used for a heater, a water heater, a gas stove, and the like, and particularly relates to a gas combustion device in which a gas supply amount to a combustion unit is adjusted by a proportional valve.

Many gas combustion apparatuses are provided with a proportional valve in a gas supply pipe. This proportional valve has a valve seat formed in the gas passage and a valve body that contacts and separates from the valve seat, and adjusts the amount of gas supplied to the combustion section by varying the gap between the valve body and the valve seat. In some cases, the valve body and the valve seat adhere to each other and the gas supply amount is not properly adjusted.
Therefore, conventionally, when the combustion stop time of the combustor has exceeded a predetermined time, the sticking release operation for releasing the sticking between the valve body and the valve seat by temporarily setting the proportional valve to the maximum opening degree before the start of combustion. Had gone.
Japanese Patent No. 3,596,796

  However, in the gas combustion apparatus, the sticking release operation is not performed unless the combustion stop time elapses over a predetermined time regardless of whether the proportional valve is stuck or not. Therefore, if the operation of starting combustion is performed within a predetermined time after the combustion is stopped when the proportional valve is in a fixed state, the gas supply amount to the combustor is not properly adjusted, and the combustor causes poor ignition or fire extinguishing in the middle. There is a fear. In addition, if the operation of starting combustion is repeatedly performed within a predetermined time after the combustion is stopped, there is a possibility that ignition failure or fire extinguishing may be repeated unless the proportional valve is fixed.

  The present invention has been made in view of the above circumstances. When there is a possibility of the proportional valve sticking regardless of the combustion stop time, the proportional valve is released so that the proportional valve operates normally. It is an object of the present invention to provide a gas combustion apparatus that performs the above-described process.

(1) A gas combustion apparatus according to the present invention comprises:
An on-off valve for opening and closing a gas passage for supplying fuel gas to the combustor;
A proportional valve that adjusts the amount of gas supplied to the combustor by varying the opening of the gas passage;
A detector for detecting poor ignition and fire extinguishing in the combustor;
When the detector detects a poor ignition or a fire extinguishing in the combustor, the proportional valve is temporarily set to the maximum opening degree after the on-off valve is closed or after the on-off valve and the proportional valve are closed. And a control means for controlling so as to be.
Thereby, when ignition failure or fire extinguishing occurs in the combustor, sticking of the proportional valve can be eliminated by temporarily setting the proportional valve to the maximum opening. Therefore, regardless of the combustion stop time of the combustor, when there is a risk of the proportional valve sticking, the proportional valve can be operated normally.

(2) A gas combustion apparatus according to the present invention comprises:
An on-off valve for opening and closing a gas passage for supplying fuel gas to the combustor;
A proportional valve that adjusts the amount of gas supplied to the combustor by varying the opening of the gas passage;
A detector for detecting poor ignition and fire extinguishing in the combustor;
When the above-mentioned detector starts combustion for the first time after detecting an ignition failure or a fire extinguisher in the combustor, control is performed so that the proportional valve temporarily reaches a maximum opening degree before the on-off valve is opened. Means.
As a result, when the combustion is started for the first time after ignition failure or mid-fire extinguishment has occurred in the combustor, the proportional valve can be temporarily set to the maximum opening to eliminate the sticking of the proportional valve. Therefore, regardless of the combustion stop time of the combustor, when the combustion is started for the first time after ignition failure or fire extinguishing occurs in the combustor, the proportional valve can be operated normally.

  According to the present invention, regardless of the combustion stop time, when the ignition failure or the fire extinguishing occurs in the combustor, the sticking of the proportional valve is eliminated, and the opening control of the gas passage is normally performed to the combustor. The gas supply amount is adjusted normally. As a result, it is possible to prevent ignition failure and fire extinguishing due to the fixed proportional valve.

Embodiments of the present invention will be described with reference to the accompanying drawings.
In addition, the following embodiment is a gas hot air heater of one embodiment of the gas combustion apparatus according to the present invention.
As shown in FIG. 1, this gas warm air heater 1 includes a combustor 11 such as a burner for burning fuel gas, a fan 12 for blowing warm air heated by the combustor 11, and a combustor 11 by discharge. An ignition electrode 13 for igniting, a thermocouple (detector) 14 for detecting an ignition failure or a fire extinguishing in the combustor 11, and a gas supply of fuel gas to the combustor 11 provided in the gas supply pipe 2 And a control unit 4 having a microcomputer or the like.

  Further, the gas hot air heater 1 includes an operation switch 15, a temperature setter 16 for setting the room temperature, a room temperature sensor 17 for detecting the room temperature, a display 18, a storage unit 19, and the like. The control unit 4 controls each unit of the gas hot air heater 1 based on signals from the operation switch 15, the room temperature setter 16, the room temperature sensor 17, the storage unit 19, and the like.

  The valve device 3 includes two on-off valves 6 and 7 that open and close the fuel gas passage 30, and a proportional valve 5 that adjusts the amount of gas supplied to the combustor 11 by changing the opening of the gas passage 30. Is provided. In the valve device 3, the fuel gas from the gas supply source passes through the two on-off valves 6 and 7 from the gas inlet 31 and flows into the proportional valve 5. The gas supply amount is adjusted and sent from the gas outlet 32 to the combustor 11.

  The on-off valves 6 and 7 are composed of electromagnetic valves having a valve body, a plunger, an electromagnet, and the like, and are opened when the electromagnet coil is energized, and are closed when the energization of the coil is interrupted. In addition, in the said valve apparatus 3, although the two on-off valves 6 and 7 are provided, one piece may be sufficient.

  The proportional valve 5 includes a valve seat 52 formed in the gas passage 30, a valve body 51 that contacts and separates from the valve seat 52, and an electromagnetic coil 53 that generates an electromagnetic force so as to move the valve body 51 in the valve opening direction. Is provided. The valve body 51 and the valve seat 52 may be fixed due to various circumstances such as the material of the valve body 51, the component of the fuel gas, the temperature environment, and the valve closing time.

  The valve seat 52 is formed at the boundary between the primary chamber 33 that communicates with the gas passage 30 on the gas inflow side and the secondary chamber 34 that communicates with the gas outlet 32. The valve body 51 is suspended by a rod 54 and is urged in the valve closing direction by a spring 55 provided on the secondary chamber 34 side. A diaphragm 56 is attached to the rod 54. The diaphragm 56 is disposed at the boundary between the storage portion 35 and the primary chamber 33, and the outer periphery thereof is sandwiched by the joint portion between the primary chamber 33 and the storage portion 35. The storage unit 35 is released to the atmosphere through the opening 57, and the atmospheric pressure is atmospheric pressure. In addition, the electromagnetic coil 53, the ferrite magnet 53b, and the armature 53a are accommodated in the accommodating portion 35, and the distal end portion of the armature 53a is in contact with the head of the rod 54.

  The proportional valve 5 is controlled by the control unit 4 so that the amount of current supplied to the electromagnetic coil 53 is controlled, and the armature 53a is moved by electromagnetic force corresponding to the amount of current supplied to the electromagnetic coil 53. The rod 54 is pushed, and the valve body 51 connected to the rod 54 is separated from the valve seat 52. At this time, the valve body 51 is held at a position where the force by which the armature 53 a is pushed by the electromagnetic coil 53 and the resultant force of the tension of the spring 55 and the pressure received by the diaphragm 56 is balanced, and the valve body 51 and the valve seat 52 are positioned. The opening is set. Thus, the opening degree of the proportional valve 5 is set according to the energization amount to the electromagnetic coil 53, and the gas supply amount to the combustor 11 is adjusted.

  In addition, since the supply gas pressure acts on the diaphragm 56 on the surface side of the primary chamber 33, when the supply gas pressure in the primary chamber 33 fluctuates, a force that displaces the valve body 51 via the rod 54 works. The opening degree between 51 and the valve seat 52 changes. That is, the proportional valve 5 has a governor performance that keeps the gas pressure in the secondary chamber 34 at a substantially predetermined pressure regardless of fluctuations in the supply gas pressure flowing into the primary chamber 33.

Next, the control operation by the control unit 4 will be described with reference to FIG.
Referring to FIG. 2, when the operation switch 15 is turned on after the power is turned on (S1), before the fan 12 is driven and the combustion start operation is executed, this operation start operation is an ignition failure or an error in the middle of the fire. Whether or not the operation is the first operation after the cancellation is confirmed from the storage unit 19, and if it is not the first operation after the error is canceled, the operation immediately proceeds to the ignition operation of the combustor 11.

  On the other hand, if the operation is the first operation after the error is released, the electromagnetic coil 53 of the proportional valve 5 is energized for about 0.5 seconds to temporarily open and close the proportional valve 5 to the maximum opening degree (proportionality of the closed state). After the valve 5 is fully opened and closed (S3), the combustion operation of the combustor 11 is started. As described above, the proportional valve 5 is once fully opened, so that the valve body 51 and the valve seat 52 can be prevented from sticking to each other.

  The ignition operation of the combustor 11 is performed by setting the opening degree of the proportional valve 5 to an ignition opening degree suitable for ignition, opening the on-off valves 6 and 7 (S4), and energizing the ignition electrode 13 for a predetermined time. Discharge. Thereby, the fuel gas of the gas supply amount according to the ignition opening degree of the proportional valve 5 is supplied to the combustor 11, and continuous discharge is started at the ignition electrode 13 to perform an ignition operation.

  During this ignition operation, the thermocouple 14 detects ignition (S5, S6). If the output voltage of the thermocouple 14 does not exceed a predetermined value even after a predetermined time has elapsed after the ignition electrode 13 starts discharging, it is determined that the ignition is defective (S7), and the next error process is executed.

That is, a predetermined error display indicating an ignition failure is displayed on the display 18, and the on-off valves 6 and 7 and the proportional valve 5 are closed (S8). The energization is performed for 5 seconds, and the proportional valve 5 is temporarily opened to the maximum opening degree to perform an opening / closing operation (S9). In this way, when the proportional valve 5 is fully opened, when the ignition failure is caused by the sticking between the valve body 51 and the valve seat 52, the sticking between the valve body 51 and the valve seat 52 can be released. The ignition failure error is stored in the storage unit 19.
Then, when the operation switch 15 is turned off (S10), error cancellation for deleting the error display on the display 18 is performed (S11).

  On the other hand, when the ignition of the combustor 11 is detected by the output voltage of the thermocouple 14 by the ignition operation (S6), the amount of current supplied to the electromagnetic coil 53 of the proportional valve 5 is adjusted to increase the opening of the proportional valve 5. And combustion control in the combustor 11 is performed. For example, at the initial stage of ignition, the proportional valve 5 is operated with the maximum opening degree and the heating capacity is maximized, and then the proportional temperature is set so that the detected temperature (room temperature) of the room temperature sensor 17 becomes the set temperature set by the temperature setter 16. A temperature control operation is performed by appropriately controlling the opening degree of the valve 5. In this way, the heating operation is executed.

  During this heating operation, the thermocouple 14 is constantly monitored to see if a fire extinguishing is occurring in the combustor 11. When it is detected during the heating operation that the output voltage of the thermocouple 14 continues to be less than a predetermined value for a certain period of time, fire extinguishing of the combustor 11 is confirmed (S12, S13), and the next error is detected. Process.

That is, a predetermined error message indicating fire extinguishing on the way is displayed on the display 18 and the on-off valves 6 and 7 and the proportional valve 5 are closed (S8), and then, as in the case of the ignition failure, the proportional valve 5 is energized for about 0.5 second, and the proportional valve 5 is temporarily opened to the maximum opening degree to be opened and closed (S9). In this case as well, once the proportional valve 5 is fully opened, when the fire extinguishing is due to the sticking between the valve body 51 and the valve seat 52, the sticking between the valve body 51 and the valve seat 52 can be released. This fire extinguishing error is stored in the storage unit.
Then, when the operation switch 15 is turned off (S10), error cancellation for deleting the error display on the display 18 is performed (S11).

  When the operation switch 15 is turned off during the heating operation (S14), the on-off valves 6 and 7 and the proportional valve 5 are closed (S15), and the fan 12 is driven after the post-purge operation for a predetermined time. Stop and end the heating operation.

  As described above, according to the present embodiment, when ignition failure or fire extinguishing occurs in the combustor 11, an opening / closing operation for temporarily setting the proportional valve 5 to the maximum opening degree is performed (S9 in FIG. 2). Thus, at least the sticking of the valve body 51 and the valve seat 52 of the proportional valve 5 can be eliminated, and the proportional valve 5 can be operated normally. Therefore, when combustion is started next, poor ignition or fire extinguishing due to the fixed proportional valve 5 can be prevented.

  In addition, regardless of the combustion stop time of the combustor 11, when combustion is started for the first time after ignition failure or fire extinguishing occurs in the combustor 11, an opening / closing operation for temporarily setting the proportional valve 5 to the maximum opening degree is performed. (S3 in FIG. 2) By this, at least sticking of the valve body 51 and the valve seat 52 of the proportional valve 5 can be eliminated, and the proportional valve 5 can be operated normally. Therefore, at the start of combustion, it is possible to prevent ignition failure and fire extinguishing due to the sticking of the proportional valve 5.

  In this way, regardless of the combustion stop time, when there is a possibility that the proportional valve 5 is stuck, the proportional valve 5 is released so that the proportional valve 5 operates normally. Ignition failure and fire extinguishing due to sticking can be prevented.

  Further, conventionally, when the combustion stop time of the combustor 11 has exceeded a predetermined time regardless of whether the proportional valve 5 is fixed, an operation is performed to temporarily set the proportional valve 5 to the maximum opening degree at the start of combustion. Even when the proportional valve 5 is not fixed, the proportional valve 5 is operated to the maximum opening every time combustion is started. Therefore, even when the proportional valve 5 is not fixed, if the operation of the proportional valve 5 is frequently performed as described above, the hysteresis characteristic of the proportional valve 5 changes, the position of the valve body 51 is shifted, and the like. May occur and the gas pressure (gas secondary pressure) to the combustor 11 may fluctuate significantly from the design time.

On the other hand, in this embodiment, regardless of the combustion stop time of the combustor 11, the maximum opening operation of the proportional valve 5 is performed only when ignition failure or mid-fire extinguishment occurs in the combustor 11. The opening degree control of the proportional valve 5 can be stably performed over a long period of time without causing large fluctuations in the characteristics of the proportional valve 5.
From the above, in the present embodiment, the opening degree of the proportional valve 5 is normally controlled during the combustion operation of the combustor 11, and ignition failure and fire extinguishing can be prevented.

The present invention is not limited to the above embodiment, and various design changes can be made.
For example, as the control of the control unit 4, when the combustion start is the first time after the error cancellation of the ignition failure or the fire extinguishing in the middle, the operation of setting the proportional valve 5 to the maximum opening degree is performed (S 3 in FIG. 2). Even in the first combustion start after the cancellation, the proportional valve 5 may be operated to the maximum opening only when the combustion stop time has passed for a predetermined time (for example, about 5 minutes) or more. In this case, it is because the proportional valve 5 is operated to the maximum opening degree and the sticking release operation of the proportional valve 5 is performed when the previous ignition failure or fire extinguishing occurs (S9 in FIG. 2).

  Further, in the control of the control unit 4, when the first combustion start is performed after the error is released, the proportional valve 5 is temporarily set to the maximum opening degree (S3 in FIG. 2), and at this time, the proportional valve is closed. You may make it make it the opening degree suitable for ignition, without making the valve 5 close, after making the valve 5 into the maximum opening degree.

  Further, in the control of the control unit 4, if ignition failure or fire extinguishing occurs, the proportional valve 5 is closed together with the on-off valves 6 and 7 (S8 in FIG. 2). At this time, the on-off valve 6 , 7 may be closed first, and the proportional valve 5 may be operated at the maximum opening without closing.

  In the control of the control unit 4, if ignition failure or fire extinguishing occurs several times in succession, combustion may be prohibited by not opening the on-off valves 6 and 7. Note that the number of occurrences of poor ignition or fire extinguishing may be stored in the storage unit 19.

  The valve device 3 may be one in which the proportional valve 5 is disposed between the two on-off valves 6 and 7, or the on-off valves 6 and 7 and the proportional valve 5 are configured as separate units. But you can.

  Further, the proportional valve 5 and the open / close valves 6 and 7 are not limited to electromagnetic valves driven by electromagnets, but are special valves driven by electric valves driven by motors, electric forces of piezoelectric elements, magnetic forces of magnetostrictive elements, and the like. An electrically driven valve such as a driven valve may be used.

  Moreover, the gas combustion apparatus which concerns on this invention can be used not only as a warm air heater but as various combustion apparatuses, such as a water heater and a gas stove.

It is a mimetic diagram showing a schematic structure of a gas warm air heater which is one embodiment of a gas combustion device concerning the present invention. It is a flowchart which shows the control flow of the gas warm air heater by embodiment.

Explanation of symbols

1 Gas hot air heater (gas combustion device)
2 Gas supply pipe 3 Valve device 4 Control unit (control means)
5 Proportional valves 6, 7 On-off valve 11 Combustor 14 Thermocouple (detector)
30 Gas passage 51 Valve body 52 Valve seat

Claims (2)

An on-off valve for opening and closing a gas passage for supplying fuel gas to the combustor;
A proportional valve that adjusts the amount of gas supplied to the combustor by varying the opening of the gas passage;
A detector for detecting poor ignition and fire extinguishing in the combustor;
When the detector detects a poor ignition or a fire extinguishing in the combustor, the proportional valve is temporarily set to the maximum opening degree after the on-off valve is closed or after the on-off valve and the proportional valve are closed. And a control means for controlling the gas combustion apparatus. An on-off valve for opening and closing a gas passage for supplying fuel gas to the combustor;
A proportional valve that adjusts the amount of gas supplied to the combustor by varying the opening of the gas passage;
A detector for detecting poor ignition and fire extinguishing in the combustor;
When the above-mentioned detector starts combustion for the first time after detecting an ignition failure or a fire extinguisher in the combustor, control is performed so that the proportional valve temporarily reaches a maximum opening degree before the on-off valve is opened. And a gas combustion apparatus.

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