JP5553144B2 - Method for driving solenoid valve and combustion apparatus - Google Patents

Description

The present invention relates to a method for suitably driving an electromagnetic valve used for fluid control and the like, and a combustion apparatus.

  The electromagnetic valve is used for on / off switching of fuel supply in a combustion apparatus, for example. One example of a device for driving such an electromagnetic valve is disclosed in Patent Document 1. The device described in this document drives a solenoid valve by a PWM (Pulse Width Modulation) system, and includes a switching element for turning on and off the DC voltage application to the solenoid of the solenoid valve. A PWM signal is used as a control signal for operating the switching element. When causing the solenoid valve to open, a signal having a duty ratio of 100% is input to the switching element. Further, after the electromagnetic valve is opened, a PWM signal having a duty ratio lower than that during the valve opening operation is input to the switching element as means for maintaining the state. According to such a configuration, during the valve opening operation of the solenoid valve, the power supplied to the solenoid can be increased to ensure the valve opening operation. On the other hand, when the valve open state is maintained thereafter, the amount of power supplied to the solenoid can be suppressed to save energy.

  However, the prior art still has room for improvement as described below.

  That is, in the prior art, during the period in which the solenoid valve is in the open state, the solenoid is merely applied with a voltage having a duty ratio lower than that during the valve opening operation, and the power supplied to the solenoid is always constant. It is suppressed. For this reason, an instantaneous power failure (for example, a power failure for a short time that does not reset the operation control microcomputer) occurs during the valve open state retention period, and once the solenoid valve is closed, the solenoid Even if the power supply is resumed, the power is small, and the electromagnetic valve cannot be properly returned to the open state. In addition, even when a large pressure fluctuation occurs in the piping path to which the solenoid valve is attached, the solenoid valve may unexpectedly switch from the open state to the closed state. In some cases, the solenoid valve cannot be returned to the open state. In this case, the place where the electromagnetic valve should be open in nature is actually in the closed state, and there is a demand for improvement in accurately driving the electromagnetic valve.

JP 58-65384 A

The present invention has been conceived under the circumstances as described above, and the electromagnetic valve is closed due to, for example, an instantaneous power failure while suppressing power consumption during the open state holding period of the electromagnetic valve. It is an object of the present invention to provide an electromagnetic valve driving method and a combustion apparatus that can return the electromagnetic valve to an open state and drive the electromagnetic valve appropriately even if a phenomenon that causes a state occurs.

  In order to solve the above problems, the present invention takes the following technical means.

A driving method of a solenoid valve provided by the first aspect of the present invention includes a burner, a plurality of solenoid valves for switching on / off of fuel supply to the burner, and a drive for driving the plurality of solenoid valves. A combustion apparatus comprising: a solenoid valve driving device;
That is, there is a step of supplying power by intermittently applying a DC voltage to the solenoid of the predetermined electromagnetic valve during the valve opening state holding period after the predetermined electromagnetic valve is opened. In the valve driving method, the duty ratio of the voltage applied to the solenoid is temporarily increased at a predetermined time to increase the power supplied to the solenoid during the valve open state holding period. When the solenoid valve is in a closed state, a re-opening period is provided in which the solenoid valve can be opened again , while some of the plurality of solenoid valves are The other part of the solenoid valve is opened from the closed state to the open state so as to overlap with the time when the re-opening period should be set for the part of the solenoid valves during the valve open state holding period. If there is an operation command to perform Give priority to the corresponding valve opening operation, is characterized by setting the re-valve period for opening after the valve opening operation is completed.

According to such a configuration, even if a situation occurs in which the solenoid valve is closed due to, for example, the occurrence of an instantaneous power failure or other circumstances during the open state holding period of the solenoid valve, a predetermined time thereafter A re-valve opening period is provided to supply a large electric power to the solenoid of the solenoid valve. Therefore, it is ensured that the electromagnetic valve is returned to the open state, and the electromagnetic valve can be appropriately driven to meet the original intention. In addition, the above-described re-valve opening period is only temporarily provided, and during the other periods of the valve opening state holding period, voltage is applied to the solenoid with a low duty ratio, so that power consumption is greatly reduced. There is no problem of rising.
Furthermore, according to the above configuration, when the solenoid valve is caused to perform the valve opening operation, another solenoid valve is used as a re-opening period, and a large amount of power is simultaneously supplied to the solenoid valve. Therefore, a predetermined amount of electric power can be accurately supplied to the solenoid valve that is the target of the valve opening operation, and the valve opening operation can be appropriately performed. Moreover, since it is avoided to supply a large amount of power to a plurality of solenoid valves at the same time, it is preferable to reduce the capacity of the DC power supply.

A combustion apparatus provided by the second aspect of the present invention includes a burner, a plurality of solenoid valves for switching on / off of fuel supply to the burner, and a solenoid valve drive for driving the plurality of solenoid valves. The electromagnetic valve driving device includes switching means for controlling on / off of DC voltage application to the solenoids of the plurality of electromagnetic valves, and PWM as a control signal for operating the switching means. And a signal output means capable of outputting a signal , wherein the signal output means outputs a PWM signal during a valve open state holding period after the electromagnetic valve is opened. Sometimes, the duty ratio of the voltage applied to the solenoid is temporarily increased at a predetermined time to increase the power supplied to the solenoid, and the solenoid valve is closed. Re valve duration for opening capable again to perform the opening operation on the solenoid valve are configured to be provided if, among the plurality of solenoid valves, the opening part of the solenoid valve It is in the state holding period, and the valve opening operation is performed from the closed state to the open state for the other part of the solenoid valves so as to overlap with the timing for setting the re-valve opening period. When the operation command is received, the valve opening operation corresponding to the operation command is prioritized, and the re-opening period is set after the valve opening operation is completed. Yes.

  According to such a configuration, it is possible to appropriately carry out the electromagnetic valve driving method provided by the first aspect of the present invention, which is the same as that described for the electromagnetic valve driving method of the present invention. An effect can be obtained.

  In a preferred embodiment of the present invention, the predetermined time when the signal output means temporarily increases the duty ratio of the voltage applied to the solenoid is configured to periodically come at predetermined time intervals. ing.

  According to such a configuration, it is possible to almost certainly cause the re-valve opening period thereafter regardless of the time when the electromagnetic valve in the open state is closed. Therefore, it is more preferable to ensure the operation of returning the electromagnetic valve to the open state.

In a preferred embodiment of the present invention, the signal output means further comprises detection means for detecting a predetermined phenomenon of a factor that the plurality of electromagnetic valves are closed during the valve open state holding period. However, the predetermined time when the duty ratio of the voltage applied to the solenoid is temporarily increased is when the predetermined phenomenon is detected using the detecting means.

  According to such a configuration, when the open solenoid valve is closed, the re-opening period is immediately provided, and the operation of returning the solenoid valve to the open state can be speeded up. it can.

In a preferred embodiment of the present invention, when the plurality of electromagnetic valves are in the open state holding period, the set times of the reopening period do not overlap each other.

  Such a configuration is preferable for reducing the capacity of the DC power source for supplying power to the solenoid valve. That is, if the re-opening period is set to overlap with each of the plurality of solenoid valves, the output power from the DC power supply becomes enormous, so it is necessary to increase the DC power supply capacity. According to this, such a thing can be solved. Further, when all of the plurality of solenoid valves are in the closed state, the return timing of the plurality of solenoid valves to the open state is deviated, and the plurality of solenoid valves are prevented from being simultaneously opened. . This is because, for example, when the solenoid valve is used for on / off of fuel supply in a gas combustion device, fuel is supplied to the burners of the gas combustion device all at once, so-called explosion ignition or ignition close to this. It is effective in preventing the occurrence of

  Other features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention with reference to the accompanying drawings.

It is explanatory drawing which shows an example of the structure of the outline of the combustion apparatus which concerns on this invention. It is explanatory drawing which shows the solenoid valve drive device which the combustion apparatus shown in FIG. 1 comprises. It is explanatory drawing which shows an example of the PWM signal output from the control part of the solenoid valve drive device shown in FIG. It is explanatory drawing which shows the waveform of the electric current which flows into the solenoid of a solenoid valve based on the PWM signal shown in FIG. It is a flowchart which shows an example of the operation control procedure of the control part of the solenoid valve drive device shown in FIG. It is explanatory drawing which shows an example in the case of outputting a some PWM signal from the control part of the solenoid valve drive device shown in FIG. It is explanatory drawing which shows the other example at the time of outputting a some PWM signal from the control part of the solenoid valve drive device shown in FIG.

  Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

  1 and 2 show an example of a combustion apparatus provided with an electromagnetic valve driving device to which the present invention is applied. As shown in FIG. 1, the combustion apparatus C of the present embodiment is a gas combustion apparatus, and includes a plurality of gas burners 1 (1a to 1e), a fuel gas supply path 2, a plurality of electromagnetic valves V0 to V5, an electric valve V20, An electromagnetic valve driving device SD configured using the pressure sensor 8 and the control unit 5 is provided.

  Combustion device C is used as a component of a hot water device (not shown) for performing, for example, general hot water supply or bath hot water supply, and supplies combustion gas to a heat exchanger (not shown) for hot water heating of the hot water device. Is used. However, it is needless to say that the combustion apparatus according to the present invention is not limited to those used for such applications. The gas burners 1a to 1c are, for example, for driving and burning when performing hot water supply in the hot water device, whereas the gas burners 1d and 1e are for driving and burning when performing hot water supply to the bath. Above the plurality of gas burners 1, spark plugs 30a and 30b and flame detection frame rods 31a and 31b are provided.

  The fuel gas supply path 2 includes a main pipe 20 that receives fuel gas supply from a gas pipe (not shown) laid outside, and a plurality of gas branches that are branched from the main pipe 20 and connected at one end to each of the plurality of gas burners 1. The branch pipe 21 is provided. The plurality of solenoid valves V <b> 0 to V <b> 5 are open / close valves and are attached to the main pipe 20 and the plurality of branch pipes 21. The motor-operated valve V20 is a proportional valve that can control the fuel gas flow rate steplessly, and is attached to the main pipe 20. The motor-operated valve V20 is controlled by the control unit 5 in the same manner as the electromagnetic valves V0 to V5. However, since the present invention is not intended for control of the motor-operated valve, the description thereof is omitted. The solenoid valves V0 to V5 are both of the valve closing type at the time of power failure, and their structures are the same as those of conventionally known solenoid valves. Therefore, the detailed description is abbreviate | omitted. The solenoid valves V0 to V5 include the solenoids S0 to S5 shown in FIG. 2, and the solenoids S0 to S5 can be individually opened by energizing them.

  As shown in FIG. 2, the electromagnetic valve driving device SD is configured using a DC power supply circuit 4 (DC power supply), for example, an FET, which is a power supply source to the plurality of solenoids S0 to S5, in addition to the control unit 5 described above. The plurality of switching elements SW0 to SW5 and the safety circuit section 6 are provided. The plurality of solenoids S0 to S5 and the switching elements SW0 to SW5 are connected in series to each other, and these are connected in parallel between the connection wiring L1 and the ground wiring L2 of the DC power supply circuit 4. Voltage application (energization) to the plurality of solenoids S0 to S5 is controlled by the on / off operation of the plurality of switching elements SW0 to SW5.

  The control unit 5 is configured by using a microcomputer, and can output PWM signals s0 to s5 as control signals for operating the switching elements SW0 to SW5. Therefore, the control unit 5 corresponds to an example of a signal output unit in the present invention. However, PWM signals are input to the switching elements SW0 to SW5 through AND circuits AND0 to AND5 that receive signal inputs from the control unit 5 and the safety circuit unit 6. More specifically, the safety circuit unit 6 can detect a predetermined abnormality in the combustion device C, and when there is no predetermined abnormality in the combustion device C, the safety circuit unit 6 is always “H” at the input terminals of the AND circuits AND0 to AND5. The signal is output. Therefore, when the PWM signal s0 to s5 is input from the control unit 5 to the other input terminals of the AND circuits AND0 to AND5, the PWM signal having the same waveform as that is switched from the AND circuits AND0 to AND5 to the switching elements SW0 to SW5. Is input. As a result, the switching elements SW0 to SW5 are turned on / off in response to the PWM signal, and DC voltage application to the plurality of solenoids S0 to S5 is intermittently performed.

  When a predetermined abnormality occurs in the combustion device C, the safety circuit unit 6 sets the input signal to the AND circuits AND0 to AND5 to “L”. Therefore, in this case, the switching elements SW0 to SW5 are all turned off, and the energization to the solenoids S0 to S5 is stopped. Then, the solenoid valves V0 to V5 are closed, and the fuel gas supply to the gas burner 1 is shut off. As a safety measure means in the combustion apparatus C, as a means other than the above, a switching element 70 is provided between the DC power supply circuit 4 and the solenoids S0 to S5, and when an abnormality occurs, the safety circuit section 6 and the control section 5 Means for turning off the switching element 70 by switching the signal output to the circuit 71 is also provided. Further, the voltage signal between the solenoids S0 to S5 and the switching elements SW0 to SW5 is configured to be input to the control unit 5 via a plurality of monitoring wiring units L3 including the buffer circuit 72. The control unit 5 determines that an abnormality has occurred when the signal input via the monitoring wiring unit L3 does not appropriately correspond to the PWM signal output by the control unit 5 itself. It is configured.

  The pressure sensor 8 is for detecting a pressure fluctuation of a predetermined value or more in the fuel gas supply path 2 on the upstream side of the electromagnetic valve VO (primary pressure side of the electromagnetic valve V0), for example. It corresponds to an example of means. If the primary pressure of the solenoid valve V0 rises abnormally when the solenoid valve V0 is in the open state, the solenoid valve V0 may be closed. The pressure sensor 8 is for detecting such a phenomenon. When a signal is input from the pressure sensor 8 to the control unit 5, the control unit 5 can determine the presence or absence of the phenomenon. In addition, data indicating the voltage of the DC power supply circuit unit 4 can be input to the control unit 5 via the wiring L4. The means for inputting data indicating the voltage of the DC power supply circuit section 4 to the control section 5 via the wiring L4 corresponds to another example of the detection means referred to in the present invention. When the solenoid valves V0 to V5 are in the open state, if an instantaneous power failure occurs in the DC power supply circuit unit 4, the solenoid valves V0 to V5 are closed. The control unit 5 can determine whether or not an instantaneous power failure has occurred based on the data indicating the voltage. The controller 5 outputs PWM signals s0 to s5 to control the driving of the electromagnetic valves V0 to V5. The specific contents will be described later.

  Next, an example and operation of the electromagnetic valve driving method in the combustion apparatus C described above will be described with reference to the flowchart of FIG. However, for simplicity of explanation, a case where only one solenoid valve V0 is driven among the solenoid valves V0 to V5 will be described as a representative example.

  First, in order to drive and burn the gas burner 1, when the control unit 5 receives a valve opening command (S10: YES), the control unit 5 outputs a PWM signal s1 to execute the valve opening operation of the electromagnetic valve V0. As the valve opening operation period, a first period P1 and a second period P2 are set as shown in FIG. The lengths of the first period P1 and the second period P2 are both 200 ms, for example, but are not limited thereto. In the first period P1, the control unit 5 outputs a PWM signal s0 having a duty ratio of 50%, for example (S11). Although schematically shown in FIG. 3, the PWM signal s0 is a plurality of intermittent pulse train waveforms. In the switching element SW0, an ON / OFF operation corresponding to the PWM signal s0 is performed, and intermittent voltage application with the duty ratio is applied to the solenoid S0. Next, the control unit 5 outputs a signal having a duty ratio of 100% in the second period P2 (S12). As a result, a continuous voltage is applied to the solenoid S0 over the entire period of the second period P2.

  When the voltage is applied as described above, as shown in FIG. 4, the current flowing through the solenoid S0 is larger in the second period P2 than in the first period P1. Therefore, the power supplied to the solenoid S0 is also larger in the second period P2 than in the first period P1. If the power supplied to the solenoid S0 in the first period P1 is suppressed to be relatively small, the electromagnetic force generated by the solenoid S0 is also relatively small. Then, it is possible to cause the solenoid valve V0 to perform the valve opening operation while preventing the loudspeaker and the plunger of the solenoid valve V0 from colliding with the casing (both not shown) and generating a loud sound. If the power supplied to the solenoid S0 is suppressed in the first period P1, for example, when the applied voltage to the solenoid S0 is lower than the original voltage, the valve opening operation is performed in the first period P1. May not execute properly. On the other hand, in the second period P2, since the power supplied to the solenoid S0 becomes large, a relatively strong electromagnetic force can be generated even when a phenomenon such as a decrease in the applied voltage occurs. It is possible to make the solenoid valve V0 perform the valve opening operation accurately. The fact that the valve opening operation is performed in the second period P2 should cause a phenomenon such as a decrease in the applied voltage, so that excessive power is supplied to the electromagnetic valve V0 in the second period P2. Therefore, the valve opening operation can be performed so that the plunger of the electromagnetic valve V0 does not collide with the casing vigorously. Therefore, the generation of a loud noise during the valve opening operation is appropriately suppressed.

  In the valve opening state holding period P3 after the second period P2 has elapsed, the control unit 5 returns the duty ratio of the PWM signal s0 to 50% (S13). As a result, the open state of the electromagnetic valve V0 can be maintained while suppressing power consumption. However, after entering the valve-opening state holding period P3, the control unit 5 counts time using a timer, and when the predetermined time has elapsed, resets the timer and then sets the duty ratio of the PWM signal s0 to a predetermined value. Only time is set to 100% (S14, S15: YES, S16, S17). Thereafter, the duty ratio of the PWM signal s0 is restored to 50%, and if the valve closing command is not received, the above-described processing is repeated (S18, S19: NO). When the valve closing command is received, the output of the PWM signal s0 is stopped, and the drive combustion of the gas burner 1 is thereby terminated (S19: YES, S20).

  The period in which the signal output with a duty ratio of 100% in step S17 is the revalve opening period P3 ', and its length is, for example, 200 ms. As shown in FIG. 3, the re-valve opening period P3 'is set repeatedly at a predetermined period T (for example, a period of 2.4 s). Further, as shown in FIG. 4, in the re-valve opening period P3 ', the current flowing through the solenoid S0 increases as in the second period P2. If the re-valve opening period P3 ′ is repeatedly provided at a predetermined period T, even if the electromagnetic valve V0 is closed due to some reason, the solenoid S0 is greatly increased when the re-valve opening period P3 ′ arrives. Electric power is supplied, and the electromagnetic valve V0 can be returned to the open state.

  On the other hand, even when the control unit 5 detects a predetermined phenomenon during the valve-opening state holding period P3, a re-valve opening period P3 ′ is provided, and the PWM signal s0 is set to a duty ratio of 100% for a predetermined time. (S21: YES, S17). Here, the predetermined phenomenon is an instantaneous power failure of the DC power supply circuit unit 4 or an abnormal increase in the primary pressure of the electromagnetic valve V0. As described above, these phenomena are factors that cause the electromagnetic valve V0 to be closed, and are detected by the control unit 5. If the above-described predetermined phenomenon occurs and the re-opening period P3 ′ is provided immediately when the control unit 5 detects that, the operation of returning the closed electromagnetic valve V0 to the open state is performed early. Can be performed. When the solenoid valve V0 is closed due to a factor different from the instantaneous power failure or the abnormal increase in the primary pressure of the solenoid valve V0, the solenoid valve V0 is used in the re-valve opening period P3 ′ set at a predetermined cycle. Can be returned to the open state. Note that when the solenoid valve V0 is temporarily closed, the drive combustion of the gas burner 1 may be stopped, but this can be determined using the frame rods 31a and 31b, and the drive combustion is not performed. Of course, the ignition operation is executed when the operation is stopped. In the above, the electromagnetic valve V0 has been described as a representative example, but the other electromagnetic valves V1 to V5 other than this can be appropriately driven in the same manner as described above.

  On the other hand, when all or any one of the electromagnetic valves V0 to V5 is in the valve open state holding period P3, the control unit 5 performs operation control as described below.

  That is, as shown in FIG. 6, the control unit 5 outputs a PWM signal s0 to s5 with a duty ratio of 50%, for example, during the valve open state holding period P3, while having a constant cycle T or a predetermined period. When the phenomenon (the phenomenon described in step S21 described above) occurs, the re-valve opening period P3 ′ is temporarily set. However, the respective re-opening periods P3 'of the PWM signals s0 to s5 are controlled so as not to overlap with each other in time.

  Such a control is preferable for reducing the capacity of the DC power supply circuit unit 4 because large power is not simultaneously supplied from the DC power supply circuit unit 4 to each of the solenoid valves V0 to V5. . Further, when all of the electromagnetic valves V0 to V5 are in the closed state, the return timing of the electromagnetic valves V0 to V5 to the open state is shifted. In contrast to this, when the solenoid valves V0 to V5 are simultaneously returned to the open state, the fuel gas supply to each of the gas burners 1a to 1e is resumed at the same time. Therefore, when the ignition operation is performed in this state, The so-called explosion ignition or ignition in a state close to this is performed. According to the control, an effect of appropriately preventing such a problem can be obtained.

  In the gas burners 1a to 1c shown in FIG. 1, if the central gas burner 1a starts driving combustion, then the gas burners 1b and 1c can be burned and driven to burn. Similarly, in the gas burners 1d and 1e, it is possible to cause a fire transfer from the gas burner 1d to the gas burner 1e. Further, in the configuration shown in FIG. 1, only one frame rod 31a is used for, for example, three gas burners 1a to 1c, and this frame rod 31a is shared by two gas burners 1a and 1b. Has been. According to such a configuration, the manufacturing cost can be reduced by reducing the total number of frame rods. In addition, as described below, it is possible to prevent problems from occurring when the gas burners 1a to 1c are driven. In other words, during the drive combustion of the gas burners 1a to 1c, for example, even if the solenoid valves V1 and V3 are closed and the gas burners 1a and 1c are misfired, if the gas burner 1b is in drive combustion, Flame detection is performed. In this case, the control unit 5 cannot detect that the gas burners 1a and 1c are in a misfire state, and it is determined that the gas burners 1a to 1c are in the drive combustion. On the other hand, if the solenoid valve V1 is returned to the open state by the control intended by the present invention, the gas burner 1b can be transferred to the gas burner 1a to appropriately drive and burn the gas burner 1a. Moreover, if the solenoid valve V3 returns to an open state after that, the gas burner 1c can be transferred to the gas burner 1c, and the gas burner 1c can be driven and burned. Thus, by returning the solenoid valves V1 and V3 to the open state, the entire gas burners 1a to 1c can be appropriately driven. However, such a return of the solenoid valve to the open state is performed. As a means for achieving this, it is meaningful to provide a reopening period intended by the present invention.

  As shown in FIG. 7, for example, during the valve-opening state holding period P3, when the PWM signal s0 is output, the re-opening period P3 ′ is scheduled to be performed at a predetermined time t1, whereas that time The valve opening command for the electromagnetic valve V4 may be received substantially at the same time as t1. In such a case, the control unit 5 gives priority to the valve opening operation of the electromagnetic valve V4, sets the first period P1 and the second period P2 as the valve opening operation period, and outputs the PWM signal s4. The re-valve opening period P3 'for the PWM signal s0 is provided after the end of the second period P2. For the other PWM signals s1 to s3, the timing of the re-valve opening period P3 'is shifted in accordance with the above. Although omitted in FIG. 7, the PWM signals s0 to s0 are also avoided so as to avoid this valve opening operation timing even when the valve opening operation of the electromagnetic valve V5 is started following the valve opening operation of the electromagnetic valve V4. The timing of the re-valve opening period P3 ′ at s3 is shifted.

  According to the control as described above, it is more preferable to prevent a large amount of power from being simultaneously supplied from the DC power supply circuit unit 4 to the solenoid valves V0 to V5 and to reduce the capacity of the DC power supply circuit unit 4. . In addition, since the valve opening operation of the solenoid valves V4 and V5 is prioritized over the setting of the re-opening period P3 ′ in the solenoid valves V0 to V3, a shortage of power supplied to the solenoid valves V4 and V5 is avoided. Thus, the opening operation of the electromagnetic valves V4 and V5 can be performed more reliably.

  The present invention is not limited to the contents of the above-described embodiment. The specific configuration of the driving method of the solenoid valve according to the present invention can be changed within the intended scope of the present invention. The specific configuration of each part of the solenoid valve driving device and the combustion device according to the present invention can be varied in design in various ways.

  The specific value of the duty ratio of the PWM signal in the valve-opening state holding period referred to in the present invention is not limited to the above values (50% and 100%). The duty ratio in the reopening period only needs to be higher than the duty ratio in the normal state (excluding the reopening period) of the valve opening state holding period.

  Factors that cause the solenoid valve to be closed during the valve open state retention period include, for example, a mechanical load on the solenoid valve in addition to the occurrence of the instantaneous power failure and the abnormal increase in the primary pressure of the solenoid valve described in the above-described embodiment The impact generated by the direct action of the can also be considered. Therefore, it is possible to provide a revalve opening period when such an impact is detected, and the specific contents of the factors can be selected as appropriate. Further, unlike such a configuration, the control means does not use a detection means for detecting a predetermined factor, and the control means is a predetermined device (such as a device that may cause a load that causes the electromagnetic valve to be closed). It is also possible to provide a re-valve opening period when an output for driving is performed.

  The PWM signal for operating the switching means does not necessarily have to be output from the control unit using a microcomputer. For example, a dedicated circuit for generating a PWM signal may be provided, and the PWM signal may be output from this circuit toward the switching means. The electromagnetic valve driving method according to the present invention is intended for a valve-opening state maintaining process after the electromagnetic valve is opened, and the specific contents of the other processes are not limited. Therefore, for the normal valve opening operation before the electromagnetic valve shifts to the valve opening state holding period, for example, a signal with a duty ratio of 100% is simply output without providing the first period P1 and the second period P2. You can make it happen by doing it alone.

The combustion apparatus according to the present invention is not only used as a constituent element of a hot water apparatus such as a hot water supply apparatus, but may be configured as a combustion apparatus used for various other applications (for example, a gas fan heater, a gas stove, etc.). it can. Moreover, it can also be comprised as a combustion apparatus which uses substances other than gas (for example, fuel oil etc.) as a fuel.

C Combustion device SD Solenoid valve drive device V0 to V5 Solenoid valve S0 to S5 Solenoid (solenoid valve)
SW0 to SW5 Switching element (switching means)
s0 to s5 PWM signal L4 wiring (detection means)
P3 Valve open state holding period P3 'Revalve opening period 1 Gas burner (burner)
5 Control unit (signal output means)
8 Pressure sensor (detection means)

Claims (5)

A combustion apparatus comprising: a burner; a plurality of solenoid valves for switching on / off of fuel supply to the burner; and a solenoid valve driving device for driving the plurality of solenoid valves. Among the valves, there is a step of supplying power by intermittently applying a DC voltage to a solenoid of the predetermined electromagnetic valve during a valve open state holding period after the predetermined electromagnetic valve is opened. A method for driving a solenoid valve,
During the valve open state holding period, the duty ratio of the voltage applied to the solenoid is temporarily increased at a predetermined time to increase the power supplied to the solenoid, and the predetermined electromagnetic valve is closed. In this case, a re-opening period is provided so that this solenoid valve can be opened again .
Among the plurality of solenoid valves, another solenoid valve is in the open state holding period, and another one of the solenoid valves overlaps with the time when the re-valve opening period should be set. When there is an operation command for performing the valve opening operation from the closed state to the open state, the valve opening operation corresponding to the operation command is given priority, and after the valve opening operation is completed, A method for driving an electromagnetic valve, characterized in that an opening period is set . A burner, a plurality of solenoid valves for switching on and off the fuel supply to the burner, and a solenoid valve drive device for driving the plurality of solenoid valves,
The electromagnetic valve driving device includes:
Switching means for ON / OFF control of DC voltage application to the solenoids of the plurality of solenoid valves;
A signal output means capable of outputting a PWM signal as a control signal for operating the switching means;
A combustion device comprising:
The signal output means temporarily increases the duty ratio of the voltage applied to the solenoid at a predetermined time when outputting the PWM signal during the valve open state holding period after the electromagnetic valve is opened. The power supply to the solenoid is increased, and when the solenoid valve is in a closed state, a re-valve opening period is provided in which the solenoid valve can be opened again. Has been
Among the plurality of solenoid valves, another solenoid valve is in the open state holding period, and another one of the solenoid valves overlaps with the time when the re-valve opening period should be set. Electromagnetic part
When there is an operation command for performing the valve opening operation from the closed state to the open state, the valve opening operation corresponding to the operation command is given priority, and after the valve opening operation is completed, the re-valve opening period Is set so as to be set . 3. The combustion according to claim 2, wherein the signal output means is configured to periodically come at predetermined time intervals when the duty ratio of the voltage applied to the solenoid is temporarily increased by the signal output means. Equipment . A detector for detecting a predetermined phenomenon of a factor that the plurality of solenoid valves are closed during the valve open state holding period;
The predetermined timing when the signal output means temporarily increases the duty ratio of the voltage applied to the solenoid is when the predetermined phenomenon is detected using the detection means. The combustion apparatus as described. The combustion apparatus according to any one of claims 2 to 4, wherein when the plurality of solenoid valves are in the open state holding period, the set timings of the reopening period do not overlap each other .

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