JP4961863B2 - Drive control apparatus and combustion apparatus for inductive load - Google Patents

Description

  The present invention relates to a drive control device and a combustion device for an inductive load, and more particularly to a drive control technology for an electromagnetic pump in a combustion device including a fuel pumping electromagnetic pump operated by a half-wave rectified power source.

  2. Description of the Related Art Conventionally, a combustion apparatus using oil as a fuel includes an electromagnetic pump (inductive load) for pressure-feeding oil used as fuel to a combustion unit. This electromagnetic pump uses a direct current (more precisely, a pulsating flow) obtained by half-wave rectification of a commercial power supply (AC 100V AC power supply) as a drive power supply, and the drive / stop is provided on the power supply line. This is done by closing (ON) / opening (OFF) the contact of the mechanical relay (driving relay of the electromagnetic pump) by a control signal from a microcomputer (control unit).

  By the way, when a relay having a mechanical relay contact is used as a driving relay of an electromagnetic pump as described above, it is widely desired that the opening and closing of the relay contact is performed when no current flows through the relay contact in terms of durability of the contact. Known (for example, see Patent Documents 1 and 2 regarding a relay inserted into an AC power supply).

JP-A-6-20551 JP-A-61-51720

  However, even if an attempt is made to open and close the contact when no current is flowing through the relay contact, in the case of a mechanical relay, the contact operating time (the relay contact closing or opening command is issued and the contact is actually Therefore, unless the operation delay time is taken into consideration, the contact cannot be opened / closed when no current is flowing.

  In this regard, Patent Document 1 discloses that the operation delay time of the relay contact is measured and the output timing of the control signal to the drive relay is set in consideration of the operation delay time. No specific method or means for measuring the operation delay time is disclosed.

  On the other hand, the provision of a new circuit to measure the operation delay time of the relay contact reduces the merit of reducing the cost by using a low-rated relay, and instead of the manufacturing cost of the electromagnetic pump drive circuit. May increase.

  The present invention has been made in view of such conventional problems, and measures the operation delay time of a drive relay of an electromagnetic pump using an electric circuit provided in an existing combustion apparatus, and current is supplied to the circuit. The main object is to adjust the output timing of a control signal so that a relay contact operates when not flowing, and to provide a drive control device for an inductive load for that purpose.

In order to achieve the above object, a drive control device for an inductive load according to claim 1 of the present invention is connected to an AC power source, a rectifying element for half-wave rectification, and the AC power source via the rectifying element. An inductive load having an inductive load, a drive relay having a relay contact that opens and closes a path of a current flowing through the inductive load, and a control unit that instructs the drive relay to close / open the contact An input voltage monitoring circuit that generates a pulse wave according to the positive / negative of the voltage of the AC power supply, and outputs a constant voltage when the relay contact is in an open state; A load voltage monitoring circuit that generates a pulse wave according to a voltage pulse applied to the inductive load, and driving the inductive load configured so that the output pulse of each of the monitoring circuits is input to the control unit Control device Then, the control unit measures and stores a time (t2) during which no positive voltage is applied to the inductive load at least per cycle of the AC power supply based on the input waveform from the load voltage monitoring circuit. Based on the voltage non-application time measurement step stored in the means and the input waveform from the input voltage monitoring circuit, the relay contact is closed from being opened in synchronization with the timing (T1) when the AC power source changes from positive to negative. outputs a control signal indicating which, the first relay delay time measuring step of measuring the time (t3) at the output of the control signal from the (T1) until the falling input voltage from the load voltage monitoring circuit and having, by comparing the first relay delay time measurement time measured in step (t3) and the voltage non-application time to the inductive load (t2), the former (t3) is Is shorter than the user (t2), the first data determination step of storing in the storage means as the measured time (t3) operation delay time at the time of the relay contact closing (tcd), the first data determination step When the time (t3) measured in the first relay delay time measuring step is longer than the voltage non-application time (t2) to the inductive load, the measured time (t3) is stored in the storage means. Is not stored, and the next time the relay contact is closed from open, based on the input waveform from the input voltage monitoring circuit, in synchronization with the timing (T2) when the AC voltage changes from negative to positive A control signal is output to close the relay contact from open, and the time (t4) from when the control signal is output (T2) until the input voltage from the load voltage monitoring circuit falls is measured, A second data determination step for storing the measured time (t4) in the storage means as the operation delay time (Tcd) at the time of closing the relay contact, and thereafter controlling the relay contact to be closed from the open state. When a signal is output, the control structure is such that the control signal is output with the output timing of the control signal advanced by the operation delay time (tcd) of the relay.

That is, the drive control device for an inductive load according to claim 1 uses an input voltage monitoring circuit and a load voltage monitoring circuit provided in an existing combustion device to operate delay time (more precisely, drive relay). , The delay time when the relay contact changes from open to closed).

  Specifically, the measurement of the operation delay time when the drive relay is closed is performed by executing the following steps in the control unit.

(1) First, the time (t2) during which no positive voltage is applied to the inductive load is measured, and these values are stored in the storage means (voltage non-application time measurement step). This step is performed based on the input waveform from the load voltage monitoring circuit when the relay contact is closed. The load voltage monitoring circuit is composed of a circuit that generates a pulse wave corresponding to a voltage pulse (pulsating pulse) applied to the inductive load when the drive relay is in a closed state. By measuring each of the Hi period and the Lo period, the voltage application time (t1) and the voltage non-application time (t2) to the inductive load can be measured.

(2) Next, based on the input waveform from the input voltage monitoring circuit, a control signal for closing the relay contact from being opened in synchronization with the timing (T1) when the AC power source changes from positive to negative. The time (t3) from when the control signal is output (T1) to when the input voltage from the load voltage monitoring circuit falls is measured (first relay delay time measuring step).

  In this step, the relay contact is closed (T1) when the AC voltage changes from positive to negative, that is, according to the present invention, the AC power source is half-wave rectified by the rectifier element, so A control signal instructing “off to on” is output. Here, the load voltage monitoring circuit outputs a constant voltage when the relay contact is in an open state, and generates a pulse wave corresponding to a voltage pulse applied to the inductive load when the relay contact is in a closed state. When the relay contact is closed when the voltage applied to the inductive load is 0 (when the AC voltage is in a negative half cycle), the output of the load voltage monitoring circuit at that time The waveform falls. On the other hand, when the relay contact is closed when a positive voltage is applied to the inductive load (when the AC voltage is in a positive half cycle), the output waveform of the load voltage monitoring circuit does not rise at that time. It does not drop and falls when the next voltage applied to the inductive load becomes zero (when the AC voltage enters the next negative half cycle). That is, in this case, the timing at which the relay contact is closed does not appear on the waveform of the load voltage monitoring circuit.

(3) Utilizing such characteristics of the load voltage monitoring circuit, in the next step, the time (t3) measured in the first relay delay time measuring step and the voltage non-application time to the inductive load ( If the former (t3) is shorter than the latter (t2), the measured time (t3) is stored in the storage means as the operation delay time (tcd) when the relay contact is closed (the first t2). 1 data confirmation step).

(4) On the other hand, when the time (t3) measured in the first relay delay time measurement step is longer than the voltage non-application time (t2) to the inductive load in the first data determination step. The measured time (t3) is not stored in the storage means, and the second data determination step is executed.

  That is, in the second data determination step, the next time the relay contact is closed from open, the AC voltage changes from negative to positive based on the input waveform from the input voltage monitoring circuit (T2). Synchronously output a control signal to close the relay contact from open and measure the time (t4) from when the control signal is output (T2) until the input voltage from the load voltage monitoring circuit falls. To do. That is, the operation delay time (Tcd) when the relay contact is closed is measured with a half cycle delay from the first relay delay time measurement step, and the value is stored in the storage means.

(5) When the operation delay time (Tcd) at the time of closing the relay contact is thus measured and stored, the control unit then outputs a control signal for closing the relay contact from the open state. At this time, the control signal is output earlier by the output timing of the control signal by the operation delay time (tcd) of the relay. That is, for example, when it is desired to close the contact of the drive relay when the voltage applied to the inductive load is 0, the relay operation delay time (tcd) from the target time point during the voltage 0 period. The drive relay can be closed at the target timing by advancing the output timing of the control signal.

  In the first data determination step and the second data determination step, the case where the measured time (t3) is compared with the voltage non-application time (t2) has been described. However, the voltage non-application time (t2) and the voltage application Since the time (t1) is almost the same value, the voltage application time (t1) can be used as a comparison target.

An inductive load drive control device according to claim 2 of the present invention includes an AC power supply, a rectifying element for half-wave rectification, an inductive load connected to the AC power supply via the rectifying element, An inductive load drive circuit comprising: a drive relay having a relay contact for opening and closing a path of a current flowing through the inductive load; and a controller for instructing the drive relay to close / open the contact. An input voltage monitoring circuit that generates a pulse wave according to the positive / negative of the voltage of the AC power supply, and outputs a constant voltage when the relay contact is in an open state, and applies it to the inductive load when the relay contact is in a closed state A drive voltage monitoring circuit that generates a pulse wave according to a voltage pulse to be generated, and an inductive load drive control device configured such that an output pulse of each of the monitoring circuits is input to the control unit. The control unit Based on the input waveform from the load voltage monitoring circuit, the time (t2) during which no positive voltage is applied to the inductive load at least per cycle of the AC power supply is measured and stored in the storage means. Based on the measurement step and the input waveform from the input voltage monitoring circuit, a control signal for opening the relay contact from closing is output in synchronization with the timing (T3) when the AC voltage changes from positive to negative. , with a second relay delay time measuring step of measuring the time (t5) until reaching the input voltage from the load voltage monitoring circuit from the time the output of the control signal (T3), the second relay delay The time (t5) measured in the time measurement step and the voltage non-application time (t2) to the inductive load are compared, and the former (t5) is shorter than the latter (t2). Lever, a third data determination step of storing the measured time (t5) in the storage means as the operation delay time at the time of the relay contact opening (tod), in the third data determination step, the second relay When the time (t5) measured in the delay time measurement step is the same as the voltage non-application time (t2) to the inductive load, the measured time (t5) is not stored in the storage means, and When the relay contact is opened from the closed state, the relay contact is opened from the closed state in synchronization with the timing (T4) when the AC voltage changes from negative to positive based on the input waveform from the input voltage monitoring circuit. A control signal to output the output voltage is output, and the time (t6) from when the control signal is output (T4) until the input voltage from the load voltage monitoring circuit rises next is measured, and this measured time (t And 6) a fourth data determination step for storing the data in the storage means as an operation delay time (Tod) when the relay contact is opened, and then outputting a control signal for opening the relay contact from the closed state. Is characterized in that it has a control structure for outputting a control signal by advancing the output timing of the control signal by the operation delay time (tod) of the relay.

That is, the drive control device for an inductive load according to claim 2 uses an input voltage monitoring circuit and a load voltage monitoring circuit provided in an existing combustion device to operate delay time (more precisely, drive relay). , The delay time when the relay contact is closed to open) is measured.

  Specifically, the measurement of the operation delay time when the drive relay is opened is performed by executing the following steps in the control unit.

(1) First, at least the time (t2) during which no positive voltage is applied to the inductive load is measured, and these values are stored in the storage means (voltage non-application time measurement step). This step is the same as the voltage non-application time measurement step described above for measuring the operation delay time when the drive relay is closed.

(2) Next, based on the input waveform from the input voltage monitoring circuit, a control signal for opening the relay contact from the closed state in synchronization with the timing (T3) when the AC voltage changes from positive to negative. The time (t5) from when the control signal is output (T3) to when the input voltage from the load voltage monitoring circuit rises is measured (second relay delay time measuring step).

  In this step, the relay contact is opened (ON) at the timing (T3) when the AC voltage changes from positive to negative, that is, the AC power source is half-wave rectified with a rectifying element in the present invention. A control signal instructing “off” is output. Here, the load voltage monitoring circuit outputs a constant voltage when the relay contact is in an open state, and generates a pulse wave corresponding to a voltage pulse applied to the inductive load when the relay contact is in a closed state. When the relay contact is opened when the voltage applied to the inductive load is 0 (when the AC voltage is in a negative half cycle), the output waveform of the load voltage monitoring circuit at that time Get up. On the other hand, even if the relay contact is opened when a positive voltage is applied to the inductive load (when the AC voltage is in a positive half cycle), the output waveform of the load voltage monitoring circuit has already risen at that time. Since the state of Hi is maintained unless the relay contact is closed, in this case, the timing at which the relay contact is opened cannot be confirmed by the waveform of the load voltage monitoring circuit.

(3) The invention of claim 2 utilizes the characteristics of such a load voltage monitoring circuit, and in the next step, the time (t5) measured in the second relay delay time measuring step and the inductive load are measured. When the former (t5) is shorter than the latter (t2), the measured time (t5) is stored as an operation delay time (tod) when the relay contact is opened. The data is stored in the means (third data determination step).

(4) On the other hand, when the time (t5) measured in the second relay delay time measurement step is the same as the voltage non-application time (t2) to the inductive load in the third data determination step. Does not store the measured time (t5) in the storage means, and executes the fourth data determination step.

  That is, in the fourth data determination step, the next time the relay contact is opened from the closed state, the AC voltage changes from negative to positive based on the input waveform from the input voltage monitoring circuit (T4). Synchronously, a control signal for opening the relay contact from the closed state is output, and a time (T6) from when the control signal is output (T4) to when the input voltage from the load voltage monitoring circuit next rises is output. The measured time (t6) is stored in the storage means as the operation delay time (Tod) when the relay contact is opened.

(5) When the operation delay time (Tod) when the relay contact is opened is measured and stored in this manner, the control unit then outputs a control signal for opening the relay contact from the closed state. In this case, the control signal is output earlier by the output timing of the control signal by the operation delay time (tod) of the relay. That is, for example, when the contact of the drive relay is to be opened when the voltage applied to the inductive load is 0, the control is performed for the relay operation delay time (tod) from the target time point during the voltage 0 period. By advancing the signal output timing, the drive relay can be opened at the target timing.

According to a third aspect of the present invention, there is provided a combustion apparatus comprising an electromagnetic pump for pumping fuel, comprising the drive control apparatus according to the first or second aspect as a drive control circuit for the electromagnetic pump. It is characterized by.

  That is, in this way, in the combustion apparatus equipped with the electromagnetic pump for fuel pressure feeding, as the safety measures of the apparatus, the input voltage monitoring circuit and the load voltage monitoring circuit are provided, so the software of the control unit is loaded. The present invention can be applied only by changing.

A combustion apparatus according to claim 4 of the present invention is a combustion apparatus including an electromagnetic pump for fuel pumping, and includes the drive control apparatus according to claim 1 or 2 as a drive control circuit of the electromagnetic pump. If the data is not confirmed in the first or third data confirmation step, the subsequent second or fourth data confirmation step is performed when the next combustion operation is started or when the combustion operation is stopped. It is characterized by that.

  As a result, when the data cannot be determined in the first or third data determination step, the measurement of the operation delay time and the determination process are performed at the start of the next combustion or at the time of the combustion stop. The relay contacts do not open and close many times during operation.

  According to the drive control device for inductive load according to the present invention, the mechanical operation delay time in the drive relay of the inductive load operated by the half-wave rectified power source is output to the output signals of the input voltage monitoring circuit and the load voltage monitoring circuit. On the basis of the control relay having the function of outputting a control signal for instructing the driving relay to close or open the relay contact, when the control unit controls the driving relay, Relay control with operation delay time taken into account becomes possible.

  Therefore, since the control unit can output a control signal so that the relay contact is closed or opened at a timing when no current flows through the relay contact, it is possible to improve the durability of the relay contact and It is also possible to use a low driving relay.

  Moreover, in a combustion apparatus equipped with an electromagnetic pump for fuel pumping, the present invention can be applied only by replacing the software of the control unit, so that the present invention can be applied at low cost without increasing the number of parts. .

In addition, according to the invention of claim 4, since the relay contact is not opened and closed many times during one combustion operation, when applied to a combustion heating type hot water supply apparatus, the hot water by repeated opening and closing of the relay contact is applied. The operation delay time of the relay can be measured without causing deterioration of the temperature characteristics or significantly reducing the durability of the relay, and a combustion apparatus suitable for application to a hot water supply apparatus can be provided. In particular, this point is extremely useful in a hot water supply apparatus that performs instantaneous general hot water supply that requires high hot water temperature characteristics.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a drive circuit of an electromagnetic pump to which the present invention is preferably applied. This electromagnetic pump drive circuit 1 is a circuit for driving an electromagnetic pump for supplying oil to a combustion section (not shown) in a combustion apparatus using oil as fuel. In the figure, 2 is a commercial power supply of AC 100V 3 is an electromagnetic pump, 4 is a rectifying element (diode) that performs half-wave rectification, and 5 is a drive relay that opens and closes a path of a current flowing through the electromagnetic pump 3 on a power supply line 10 connected to the AC power supply 2. The relay contact 6 generates a control signal that instructs the drive relay (more specifically, the primary coil (not shown) of the relay) to close (open) / open (off) the contact. The control part is shown.

  Here, the electromagnetic pump 3 is a DC load that operates using a half-wave waveform (pulsating flow) rectified by the rectifying element 4 as a power source, and is configured by an inductive load including a coil component. Further, a power relay provided with a mechanical relay contact is used as the drive relay. Further, the control unit 6 includes a microcomputer including a control program for controlling the operation of each unit of the combustion apparatus as a main part. In the present invention, the control unit 6 is provided with a control program for the drive relay (details will be described later).

  In the illustrated electromagnetic pump drive circuit 1, in addition to the electromagnetic pump 3 described above, an igniter 11 for igniting the combustion section and a pipe (not shown) through which hot water flows are included in the power supply line 10. Are connected to the anti-freezing heaters 12 and 13 and the relay contacts 14 to 16 for controlling the driving / stopping of these heaters, and since these are not directly related to the present invention, the description thereof is omitted. To do.

  The electromagnetic pump drive circuit 1 includes a normally closed high limit switch 7 on the power line 10. The high limit switch 7 is arranged in the vicinity of the combustion can body (combustion section), and automatically detects the temperature when the combustion can body exceeds a predetermined temperature and becomes high temperature regardless of the control by the control section 6. It consists of a switch whose contact is opened. That is, when an abnormality occurs in the combustion apparatus and the combustion can body becomes high temperature, the contact of the high limit switch 7 is automatically opened (opened), power supply to the electromagnetic pump 3 is cut off, and The fuel supply is automatically stopped.

  The electromagnetic pump drive circuit 1 includes a high limit monitoring circuit 8 that monitors whether the high limit switch 7 is open or closed by monitoring the line voltage of the power supply line 10, and the electromagnetic pump 3. There is provided an electromagnetic pump monitoring circuit 9 for monitoring whether the electromagnetic pump 3 is in a driving / stopping state by monitoring the applied voltage, and the circuit outputs of these monitoring circuits 8 and 9 are controlled as described above. It is input to part 6.

  Specifically, the high limit monitoring circuit 8 is an input voltage monitoring circuit that generates a pulse wave according to the positive / negative of the voltage of the commercial power supply 2, and specifically, the power line 10 and the control unit 6. And a direct-current voltage source (DC5V power source in the illustrated example) Vcc that supplies a signal voltage to the control unit 6 are mainly configured.

  In this embodiment, when a positive voltage is applied to the power supply line 10, the high limit monitoring circuit 8 turns on the photocoupler 21, and the control unit 6 receives a 0V signal voltage (Lo signal). On the contrary, when a negative voltage is applied to the power supply line 10, the photocoupler 21 is turned off and the signal voltage (Hi signal) from the DC voltage source Vcc is applied to the control unit 6. (See FIG. 2).

  That is, when the pulse wave corresponding to the positive / negative of the voltage of the commercial power supply 2 is input from the high limit monitoring circuit 8 to the control unit 6, the contact of the high limit switch 7 is closed (closed). When the pulse wave input is stopped and the input signal continues to be in the Hi state, the contact of the high limit switch 7 is in an open state. Then, it is determined that an abnormality has occurred in the combustion device, and a predetermined safe operation is performed.

  On the other hand, the electromagnetic pump monitoring circuit 9 is a load voltage monitoring circuit that monitors the voltage applied to the electromagnetic pump 3, and insulates the power line 10 from the control unit 6 in the same manner as the high limit monitoring circuit 8. The photocoupler 22 and the DC voltage source (DC5V power source in the illustrated example) Vcc2 for supplying a signal voltage to the control unit 6 are mainly configured.

  In the present embodiment, when the relay contact 5 is in the open state, the electromagnetic pump monitoring circuit 9 turns off the photocoupler 22 and outputs the signal voltage (DC5V) from the DC voltage source Vcc2. When the relay contact 5 is in the closed state, the photocoupler 22 is turned on, and a pulse wave corresponding to a voltage pulse (half-wave rectified pulsating pulse) applied to the electromagnetic pump 3 is generated and output. (See FIG. 2).

  That is, when a constant voltage (DC 5 V) is continuously input from the electromagnetic pump monitoring circuit 9, the control unit 6 puts the relay contact 5 into an open state (in other words, the electromagnetic pump 3 is stopped). On the other hand, when a pulse wave corresponding to the half-wave rectified pulsating pulse is input, the relay contact 5 is in a closed state (in other words, the electromagnetic pump 3 is in a driving state). to decide.

  By the way, the high limit monitoring circuit 8 and the electromagnetic pump monitoring circuit 9 configured in this way are both monitoring circuits conventionally provided in a combustion apparatus including the electromagnetic pump 3 for fuel pressure feeding. In the combustion apparatus according to the present invention, using the output signals from the monitoring circuits 8 and 9, the control unit 6 operates the operation delay time of the drive relay (more precisely, when the relay contact 5 is closed from the open state). The operation delay time tcd and the operation delay time tod when the relay contact 5 is opened from the closed state) are measured. This point will be described below with reference to FIGS.

A. FIG. 2 is a timing chart for explaining a procedure for measuring the operation delay time tcd when the relay contact 5 is closed (when the contact is closed) . 2 (a) shows the voltage waveform of the commercial power supply 2, FIG. 2 (b) shows the output waveform of the high limit monitoring circuit, FIG. 2 (c) shows the voltage waveform applied to the electromagnetic pump 3, and FIG. (d) to (f) show output waveforms of the electromagnetic pump monitoring circuit, respectively.

(1) In measuring the operation delay time tcd when the contact of the drive relay is closed, in the present invention, first, the control unit 6 sets at least the time t2 during which no positive voltage is applied to the electromagnetic pump 3. (In this embodiment, the time t1 during which the voltage is applied is also measured), and these values are stored in a memory (storage means) such as a RAM included in the microcomputer constituting the control unit 6 (hereinafter referred to as this The process is referred to as “voltage non-application time measuring step”).

  Here, the measurement and storage of the voltage application time t1 and the voltage non-application time t2 are performed based on the input waveform from the electromagnetic pump monitoring circuit 9 when the relay contact 5 is closed (FIG. 2 (d). )reference). That is, as described above, the electromagnetic pump monitoring circuit 9 generates and outputs a pulse wave corresponding to the voltage pulse (pulsating pulse) applied to the electromagnetic pump 3 when the relay contact 5 is in the closed state. By measuring each of the Hi period and Lo period of the pulse wave, the voltage application time t1 and the voltage non-application time t2 to the electromagnetic pump 3 are measured.

  Note that this step can be measured based on the output waveform of the high limit monitoring circuit 8, or can be obtained by calculation from the frequency of the commercial power source 2, but as will be described later, in the present invention, Since the operation delay time of the drive relay is measured based on the output waveform of the electromagnetic pump monitoring circuit 9, it is desirable to measure the voltage application time t1 and the voltage non-application time t2 based on the output waveform of the electromagnetic pump monitoring circuit 9. This embodiment is also configured as such.

  In the present embodiment, the measurement and storage of the voltage application time t1 and the voltage non-application time t2 are performed when the combustion device is installed (installed on site) and the combustion device is turned on (in other words, the control unit). 6 is the first combustion operation after the power supply is started (here, the combustion operation is an artificially instructed start of combustion (in the case of a combustion heating type hot water supply device, the passage through the operation of opening the hot water tap). (Including the case where combustion is started upon detection of water). In other words, this process can be performed before the construction of the combustion device (in other words, at the time of shipment inspection at the time of factory shipment), but in this case, the nonvolatile memory is used as a memory for storing these values. Memory is required. In this embodiment, since the memory (specifically, volatile RAM) provided in the microcomputer is used as a storage means for these values, this step is executed at the time of the first combustion operation after the construction of the combustion apparatus. I am going to do that.

(2) When the voltage application time t1 and the voltage non-application time t2 for the electromagnetic pump 3 are measured and stored in this way, the control unit 6 performs the high limit monitoring circuit during the next combustion operation. 8, based on the input waveform from 8, the relay contact 5 is closed from the open state in synchronization with the timing T 1 when the voltage of the commercial power supply 2 changes from positive to negative (the timing when the waveform of the high limit monitoring circuit 8 falls) ( A control signal indicating that the control signal is off to on) is output to the drive relay, and a time t3 from when the control signal is output T1 until the input voltage from the electromagnetic pump monitoring circuit 9 falls is measured (hereinafter referred to as “the control signal”). This process is referred to as “first relay delay time measurement step”).

  In this step, the timing T1 at which the voltage of the commercial power source changes from positive to negative, that is, in this embodiment, the commercial power source is half-wave rectified by the rectifying element 4 and supplied to the electromagnetic pump 3, so this timing T1 is The timing is the same as the timing at which the voltage supplied to the electromagnetic pump 3 becomes 0 V, and the control unit 6 outputs a control signal instructing closing of the relay contact (off to on) in accordance with the timing T1.

  Here, the electromagnetic pump monitoring circuit 9 outputs a constant voltage (DC 5 V in this embodiment) when the relay contact 5 is in an open state, and generates a voltage pulse applied to the electromagnetic pump 3 when the relay contact 5 is in a closed state. Since the circuit is configured to generate a corresponding pulse wave, the relay contact is closed while the applied voltage to the electromagnetic pump 3 immediately after the timing T1 is 0 V (when the AC voltage is in a negative half cycle). When the generation operation is completed, the output waveform of the electromagnetic pump monitoring circuit 9 falls at that time (see t3 in FIG. 2 (d)).

  On the other hand, when the closing operation of the relay contact 5 is completed when a positive voltage is applied to the electromagnetic pump 3 (when the AC voltage is in a positive half cycle), at this time, along with the operation of the relay contact 5 The output waveform of the electromagnetic pump monitoring circuit 9 does not fall, and falls when the voltage applied to the electromagnetic pump 3 becomes 0 V again (when the AC voltage enters the next negative half cycle) (FIG. 2 (e ) T3)). That is, in this case, since the output waveform of the electromagnetic pump monitoring circuit 9 is in the Hi period even when the relay contact 5 is closed, the timing when the relay contact 5 is closed appears on the output waveform of the electromagnetic pump monitoring circuit 9. Absent.

(3) When the time t3 until the input voltage from the electromagnetic pump monitoring circuit 9 falls is measured in this way, the control unit 6 then determines the time t3 measured in the first relay delay time measurement step. If the former t3 is shorter than the latter t2 by comparing the voltage non-application time t2 to the inductive load, the measured time t3 is stored in the memory as the operation delay time tcd when the relay contact is closed ( Hereinafter, this process is referred to as a “first data determination step”).

(4) On the other hand, in the first data determination step, when the time t3 measured in the first relay delay time measurement step is longer than the voltage non-application time t2, the relay contact closing starting from the timing T1 is performed. The measurement of the operation delay time tcd at the time of formation is failed, and the control unit 6 stores the fact that the measurement has failed without storing the measured time t3 in the memory, and in this combustion operation, when the relay contact is closed The operation delay time tcd is not measured, and the operation delay time tcd is measured again in the following procedure when the combustion operation is performed next time.

  That is, at the time of the next combustion operation performed after the previous failure (when the relay contact is closed again from the open state), the control unit 6 reads the previous combustion from the record of “measurement failure” stored in the storage means. When it is confirmed that the measurement of the operation delay time tcd has failed during operation, this time, based on the input waveform from the high limit monitoring circuit 8, this time in synchronization with the timing T2 when the voltage of the commercial power supply changes from negative to positive. A control signal for closing the relay contact 5 from the open state is output. Then, the time t4 from when the control signal is output T2 to when the input voltage from the electromagnetic pump monitoring circuit 9 falls is measured. That is, in the second measurement, the operation delay time Tcd when the relay contact is closed is measured by delaying the output timing of the control signal by a half cycle (1/2 cycle) from the first relay delay time measurement step described above. The value is stored in the memory (hereinafter, this process is referred to as “second data determination step”).

  Here, the reason why the output timing of the control signal is delayed by a half cycle is that the operation delay time Tcd when the relay contact is closed is longer than the half cycle of the commercial power supply due to the previous failure. This is because when the closing operation is completed, the result appears in the output waveform of the electromagnetic pump monitoring circuit 9 as a voltage fall.

(5) When the operation delay time Tcd when the relay contact is closed is measured and stored in this way, the control unit 6 opens the relay contact 5 after that, that is, after the next combustion operation is performed. When the control signal for closing is output, the output timing of the control signal is advanced by the operation delay time tcd of the drive relay and the control signal is output. Specifically, since it is preferable for durability of the contact to close the relay contact 5 when the voltage applied to the electromagnetic pump 3 is 0 V (see t0 in FIG. 2B), for example, this period When it is desired to close the contact at the midpoint of t0, the drive relay can be closed at the target timing by advancing the output timing of the control signal from the midpoint by the operation delay time tcd of the relay. .

B. Next, an operation delay time tod when the relay contact 5 is opened (when the contact is opened) will be described with reference to FIG. FIG. 3 is a timing chart for explaining the procedure for measuring the operation delay time tod when the contact of the drive relay is opened. FIG. 3 (a) shows the voltage waveform of the commercial power supply 2 and FIG. 3 (b). 3 shows the output waveform of the high limit monitoring circuit, FIG. 3C shows the voltage waveform applied to the electromagnetic pump 3, and FIGS. 3D to 3F show the output waveform of the electromagnetic pump monitoring circuit.

(1) In measuring the operation delay time tod when the contact of the drive relay is opened, in the present invention, as in the case of the operation delay time tcd when the relay contact is closed, first, the control unit 6 controls the electromagnetic pump 3. A voltage application time t1 and a voltage non-application time t2 are measured, and these values are stored in the storage means. Note that this step is the same step as the voltage non-application time measurement step described in the above-described measurement of the operation delay time tcd when the drive relay is closed, and therefore, the control unit 6 should once execute this step. There is no need to run again.

(2) Next, when the combustion operation is stopped (when the relay contact 5 of the drive relay is opened), the control unit 6 performs the above operation based on the input waveform from the high limit monitoring circuit 8. In synchronization with timing T3 when the voltage of the commercial power source changes from positive to negative, a control signal for opening the relay contact 5 from closed is output, and from the time T3 when the control signal is output, the electromagnetic pump monitoring circuit 9 The time t5 until the input voltage rises is measured (hereinafter, this process is referred to as “second relay delay time measurement step”).

  That is, in this process, the timing T3 at which the voltage of the commercial power source changes from positive to negative, that is, in this embodiment, the commercial power source 2 is half-wave rectified by the rectifier element 4 and supplied to the electromagnetic pump 3. The timing T3 is the same as the timing when the voltage supplied to the electromagnetic pump 3 becomes 0V, and the control unit 6 outputs a control signal instructing opening of the relay contact (ON to OFF) in accordance with the timing T3.

  Here, the electromagnetic pump monitoring circuit 9 outputs a constant voltage (DC 5 V in this embodiment) when the relay contact 5 is in an open state, and generates a voltage pulse applied to the electromagnetic pump 3 when the relay contact 5 is in a closed state. Since it is configured by a circuit that generates a corresponding pulse wave, the relay contact 5 is in a period when the applied voltage to the electromagnetic pump 3 that comes immediately after the timing T3 is 0 V (when the AC voltage is in a negative half cycle). When the opening operation is completed, the output waveform of the electromagnetic pump monitoring circuit 9 rises at that time (see t5 in FIG. 3 (d)).

  On the other hand, when the opening operation of the relay contact 5 is completed when a positive voltage is applied to the electromagnetic pump 3 (when the AC voltage is in a positive half cycle), the electromagnetic pump monitoring circuit is already at that time. The output waveform of No. 9 has risen (becomes a Hi period), and even if the relay contact completes the opening operation during this Hi period, the operation point does not appear in the output waveform of the electromagnetic pump monitoring circuit 9. Specifically, for example, as shown in FIG. 3 (e), when it takes (t2 + tα) time to complete the opening operation of the relay contact 5, the output waveform of the electromagnetic pump monitoring circuit 9 is t2 from the timing T3. In this case, even if the time t5 until the output voltage of the electromagnetic pump monitoring circuit 9 rises is measured (t5 = t2), the timing at which the relay contact 5 is opened is grasped. I can't.

(3) Therefore, when the control unit 6 measures the time t5 until the input voltage from the electromagnetic pump monitoring circuit 9 rises in this way, next, the time t5 measured in the second relay delay time measurement step. If the former t5 is shorter than the latter t2, the measured time t5 is stored in the memory as the operation delay time tod when the relay contact is opened (hereinafter, this step is referred to as “ This is referred to as “third data determination step”).

(4) On the other hand, in the third data determination step, when the time t5 measured in the second relay delay time measurement step is the same as the voltage non-application time t2, the relay contact starting from the timing T3 is opened. Since the measurement of the operation delay time tod is failed, the control unit 6 does not store the measured time t5 in the memory, and the measurement of the operation delay time tod when the relay contact is opened is performed when the combustion operation is stopped at this time. Instead, when the combustion operation is stopped next time, the operation delay time tod is measured again by the following procedure.

  That is, at the time of the next combustion operation stop performed after the previous failure (when the relay contact is opened again from the closed state), the control unit 6 is now based on the input waveform from the high limit monitoring circuit 8. Outputs a control signal for opening the relay contact 5 from the closed state in synchronization with the timing T4 when the voltage of the commercial power source 2 changes from negative to positive. This time, the time t6 from when the control signal is output T4 until the input voltage from the electromagnetic pump monitoring circuit 9 rises next is measured, and the measured time t6 is used as the operation delay time Tod when the relay contact is opened. Is stored in the memory. That is, in the second measurement, the operation delay time Tod when the relay contact is opened is measured by delaying the output timing of the control signal by a half cycle (1/2 cycle) from the second relay delay time measurement step described above. Is stored in the memory (hereinafter, this process is referred to as a “fourth data determination step”).

  Here, the output timing of the control signal is delayed by a half cycle in the same way as the measurement of the operation delay time tcd when the relay contact is closed, as described above, due to the previous failure. Therefore, when the relay contact completes the opening operation, the result appears as a voltage rise in the output waveform of the electromagnetic pump monitoring circuit 9.

(5) When the operation delay time Tod when the relay contact is opened is measured and stored in this manner, the control unit 6 again outputs a control signal for opening the relay contact from the closed state. The control signal is output by advancing the output timing of the control signal by the operation delay time tod of the relay. Specifically, since it is preferable for durability of the contact to open the relay contact 5 when the voltage applied to the electromagnetic pump 3 is 0 V (see t0 in FIG. 3C), for example, during this period t0 If it is desired to open the contact at the intermediate point, the drive relay can be closed at the target timing by advancing the control signal output timing from the intermediate point by the relay operation delay time tod.

  Thus, according to the combustion apparatus shown in the present embodiment, the operation delay time of the drive relay of the electromagnetic pump 3 is measured based on the output waveforms of the high limit monitoring circuit 8 and the electromagnetic pump monitoring circuit 9 that are normally provided in the combustion apparatus. Therefore, when the present invention is applied, the present invention can be easily applied only by replacing the software of the control unit 6. In other words, the number of parts does not increase and the present invention can be applied at low cost. In addition, since relay control in consideration of the operation delay time of the drive relay is possible, a relay having a low rating can be used as the drive relay of the electromagnetic pump 3.

  Note that the above-described embodiments merely show preferred embodiments of the present invention, and the present invention is not limited to these, and various design changes can be made within the scope thereof.

  For example, in the above-described embodiment, the control unit 6 delays the operation of the relay contact both when the combustion operation is started (when the relay contact 5 is closed) and when the combustion operation is stopped (when the relay contact 5 is opened). The case where the time tcd and tod are measured has been described, but the operation delay time is measured only for either one of the start of the combustion operation or the stop of the combustion operation according to the setting of the program of the control unit 6. It is also possible to configure to perform relay control.

  In the above-described embodiment, the case where only the operation delay time of the relay contact is considered in relation to the relay control has been described. However, in the case of an inductive load as shown in the present embodiment, a current delay occurs. It is also possible to perform relay control in consideration of the delay time.

  In the above-described embodiment, when the times t3 and t5 measured in the first and second relay delay time measurement steps are not fixed in the first and third data determination steps (measurement is determined to have failed). In the case of the next combustion operation or when the next combustion operation is stopped and the measurement timing is delayed by half a cycle and the measurement is performed again. For example, the next combustion operation or the next combustion operation is stopped. It is also possible to set to continue measurement without waiting. That is, for example, when the time t3 measured in the first relay delay time measurement step is longer than the voltage non-application time t2, the combustion operation is stopped at that time and the second data determination step is executed. It is also possible to configure such that the measurement timing is delayed by half a cycle and measured again.

  In the above-described embodiment, the case where the voltage non-application time measurement step is first executed when measuring the operation delay time of the relay contact is described. For example, the voltage after the second relay delay time measurement step is executed is described. It is also possible to configure to measure the application time t1 and the voltage non-application time t2.

  Moreover, although embodiment mentioned above demonstrated the case where neither operation | movement delay time tcd and tod of a relay contact exceeded one period of the frequency of the commercial power source 2, it measured by the 1st data determination step mentioned above, for example. If the time t3 to be exceeded exceeds one cycle, the value can be set as the operation delay time tcd.

  In the above-described embodiment, the case where the measurement of the operation delay time of the relay contact is performed after the construction of the combustion device has been described. It is also possible to measure the operation delay time. That is, in this case, a command signal for requesting the start of measurement of the relay operation delay time from the board inspection device side to the substrate of the control unit 6 is communicated between the board of the control unit 6 and a predetermined board inspection device. To output the control unit 6 to measure the operation delay time in the above-described procedure. And the result after construction can be eliminated by storing the result in the nonvolatile memory of the control unit 6.

  Moreover, although the case where this invention was applied to the combustion apparatus provided with the electromagnetic pump 3 for fuel pumping was shown in embodiment mentioned above, this invention is an inductive load which operate | moves with the power supply which carried out the half wave rectification of AC power supply. If it is a control device of a drive relay and has a circuit equivalent to the above-mentioned input voltage monitoring circuit (high limit monitoring circuit) and load voltage monitoring circuit (electromagnetic pump monitoring circuit), it can be applied to other devices. Is possible.

It is a circuit diagram of the drive circuit of the electromagnetic pump to which this invention is applied suitably. FIGS. 2A and 2B are timing charts for explaining a procedure for measuring an operation delay time when the contact of the drive relay according to the present invention is closed, in which FIG. 2A shows the voltage waveform of the commercial power supply 2 and FIG. FIG. 2C shows the output waveform of the limit monitoring circuit, FIG. 2C shows the voltage waveform applied to the electromagnetic pump 3, and FIGS. 2D to 2F show the output waveform of the electromagnetic pump monitoring circuit. FIG. 3 is a timing chart for explaining a procedure for measuring an operation delay time when the contact of the drive relay according to the present invention is opened, in which FIG. 3 (a) shows a voltage waveform of the commercial power supply 2 and FIG. FIG. 3C shows the output waveform of the monitoring circuit, FIG. 3C shows the voltage waveform applied to the electromagnetic pump 3, and FIGS. 3D to 3F show the output waveform of the electromagnetic pump monitoring circuit.

Explanation of symbols

1 Electromagnetic pump drive circuit 2 Commercial power supply 3 Electromagnetic pump (inductive load)
4 Rectifying element 5 Relay contact (relay contact of drive relay)
6 Control unit 7 High limit switch 8 High limit monitoring circuit (input voltage monitoring circuit)
9 Electromagnetic pump monitoring circuit (load voltage monitoring circuit)
10 Power Line 11 Igniters 21, 22 Photocoupler

Claims (4)

AC power supply, rectifying element for half-wave rectification, inductive load connected to the AC power supply via the rectifying element, and drive relay provided with a relay contact for opening and closing a path of current flowing through the inductive load And an inductive load drive circuit having a control unit for commanding closing / opening of the contact point to the drive relay,
An input voltage monitoring circuit that generates a pulse wave according to the positive / negative of the voltage of the AC power supply, and outputs a constant voltage when the relay contact is in an open state, and is applied to the inductive load when the relay contact is in a closed state. A load voltage monitoring circuit that generates a pulse wave corresponding to a voltage pulse to be output, and an inductive load drive control device configured to input an output pulse of each of the monitoring circuits to the control unit,
The controller is
Based on the input waveform from the load voltage monitoring circuit, at least the time (t2) during which no positive voltage is applied to the inductive load per cycle of the AC power supply is measured and stored in the storage means. Steps,
Based on the input waveform from the input voltage monitoring circuit, a control signal for closing the relay contact from the open state is output in synchronization with the timing (T1) when the AC voltage changes from positive to negative. And a first relay delay time measuring step for measuring a time (t3) from the output (T1) to the time when the input voltage from the load voltage monitoring circuit falls .
By comparing the time (t3) measured in the first relay delay time measurement step with the voltage non-application time (t2) to the inductive load, if the former (t3) is shorter than the latter (t2), A first data determination step for storing the measured time (t3) in the storage means as an operation delay time (tcd) when the relay contact is closed ;
In the first data determination step, when the time (t3) measured in the first relay delay time measurement step is longer than the voltage non-application time (t2) to the inductive load, the measured time The timing at which the AC voltage changes from negative to positive based on the input waveform from the input voltage monitoring circuit when (t3) is not stored in the storage means and the relay contact is next closed from open. In synchronization with (T2), a control signal is output to close the relay contact from open, and the time from when the control signal is output (T2) to when the input voltage from the load voltage monitoring circuit falls ( a second data determination step of measuring t4) and storing the measured time (t4) in the storage means as the operation delay time (Tcd) when the relay contact is closed,
After that, when outputting a control signal for closing the relay contact from the open state, it has a control configuration for outputting the control signal by advancing the output timing of the control signal by the operation delay time (tcd) of the relay. An inductive load drive control device characterized by the above. AC power supply, rectifying element for half-wave rectification, inductive load connected to the AC power supply via the rectifying element, and drive relay provided with a relay contact for opening and closing a path of current flowing through the inductive load And an inductive load drive circuit having a control unit for commanding closing / opening of the contact point to the drive relay,
An input voltage monitoring circuit that generates a pulse wave according to the positive / negative of the voltage of the AC power supply, and outputs a constant voltage when the relay contact is in an open state, and is applied to the inductive load when the relay contact is in a closed state. A load voltage monitoring circuit that generates a pulse wave corresponding to a voltage pulse to be output, and an inductive load drive control device configured to input an output pulse of each of the monitoring circuits to the control unit,
The controller is
Based on the input waveform from the load voltage monitoring circuit, the time (t2) during which no positive voltage is applied to the inductive load at least per cycle of the AC power supply is measured and stored in the storage means. Measuring steps;
Based on the input waveform from the input voltage monitoring circuit, a control signal for opening the relay contact from the closed state is output in synchronization with the timing (T3) when the AC voltage changes from positive to negative, and this control signal A second relay delay time measuring step for measuring a time (t5) from when the output voltage (T3) to when the input voltage from the load voltage monitoring circuit rises .
By comparing the time (t5) measured in the second relay delay time measurement step with the voltage non-application time (t2) to the inductive load, if the former (t5) is shorter than the latter (t2), A third data determination step for storing the measured time (t5) in the storage means as an operation delay time (tod) when the relay contact is opened ;
In the third data determination step, when the time (t5) measured in the second relay delay time measurement step is the same as the voltage non-application time (t2) to the inductive load, this measured time ( The timing at which the AC voltage changes from negative to positive based on the input waveform from the input voltage monitoring circuit when t5) is not stored in the storage means and the relay contact is next opened from closing. In synchronization with T4), a control signal for opening the relay contact from the closed state is output, and the time from when the control signal is output (T4) until the input voltage from the load voltage monitoring circuit rises next ( a fourth data determination step of measuring t6) and storing the measured time (t6) in the storage means as an operation delay time (Tod) when the relay contact is opened,
Thereafter, when a control signal for opening the relay contact from the closed state is output, the control signal is output by advancing the output timing of the control signal by the operation delay time (tod) of the relay. An inductive load drive control device characterized by the above. A combustion apparatus provided with an electromagnetic pump for fuel pressure feeding, comprising the drive control apparatus according to claim 1 or 2 as a drive control circuit for the electromagnetic pump. A combustion apparatus having an electromagnetic pump for fuel pressure delivery, wherein the drive control circuit according to claim 1 or 2 is provided as a drive control circuit for the electromagnetic pump, wherein the first or third data determination step is performed. When the data is not confirmed in the above, the combustion apparatus is characterized in that the second or fourth data confirmation step that follows is performed when the next combustion operation is started or when the combustion operation is stopped.

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