JP6079571B2 - Solenoid valve drive - Google Patents

Description

  The present invention relates to a solenoid valve driving device that controls opening and closing of a solenoid valve by controlling a current flowing through the solenoid valve.

  An injector that injects fuel into each cylinder of an internal combustion engine includes an electromagnetic valve that opens and closes when power is disconnected from the solenoid. A solenoid valve driving device for driving a solenoid valve is provided between a booster power supply unit that boosts battery voltage and charges a capacitor, a discharge switch provided between the booster power supply unit and the solenoid, and a power supply line and the solenoid. A constant current power supply unit that outputs a constant current by controlling the switching element, a cylinder selection switch that forms a current path to the solenoid, and the like.

  When a drive signal is given, the solenoid valve drive device turns on a cylinder selection switch corresponding to the drive signal throughout the injection period. In order to improve the responsiveness of the solenoid valve, the discharge switch is first turned on to allow the discharge current to flow until the solenoid drive current reaches a predetermined current value. Thereafter, a constant current necessary for maintaining the valve open state is supplied by the constant current power source until the drive period ends.

  The constant current power supply unit executes hysteresis control to turn on the switching element when the current value becomes equal to or lower than the lower limit threshold value and to turn off the switching element when the current value becomes equal to or higher than the upper limit threshold value. The solenoid valve driving device described in Patent Document 1 changes the hysteresis width according to input change information. The change information is set so that the hysteresis width is widened when the temperature increase of the electromagnetic valve driving device is suppressed, and the hysteresis width is narrowed when the decrease in the opening / closing accuracy of the electromagnetic valve is suppressed. Further, this solenoid valve driving device detects the temperature of the solenoid valve driving device and sets a hysteresis width according to the detected temperature.

JP2013-160305A

  The electromagnetic valve driving device of the conventional configuration changes the hysteresis width according to the required characteristics among the suppression of heat generation in constant current control and the suppression of fluctuations in the valve opening period. However, if the hysteresis width is widened in order to suppress heat generation, the timing at which the solenoid valve starts to close depends on the magnitude of the drive current at the end of the drive signal, and the valve is actually opened according to the drive signal. As a result, the injection amount accuracy varies. That is, the variation in heat generation and valve opening period could not be reduced at the same time.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electromagnetic valve driving device capable of reducing heat generation and reducing variations in the valve opening period in constant current control.

  When the electromagnetic valve driving device according to the first aspect receives the opening / closing command, the electromagnetic valve driving device opens / closes the electromagnetic valve by controlling the current flowing through the electromagnetic valve. The electromagnetic valve driving device includes switch means provided in an energization path to the electromagnetic valve, current detection means for detecting a current flowing through the electromagnetic valve, control means, and change means. The control means turns on the switch means when the detected current value detected by the current detection means becomes equal to or lower than the lower threshold value, and turns off the switch means when the detected current value becomes equal to or higher than the upper threshold value. As a result, the current flowing through the solenoid valve is controlled at a constant current within a settling range sandwiched between the lower limit threshold and the upper limit threshold. The changing means changes the lower limit threshold and / or the upper limit threshold in the middle of the constant current control period in which the control means receives the opening / closing command and executes constant current control, thereby narrowing the width of the settling range.

  According to this configuration, since the width of the settling range is set relatively wide until the middle of the constant current control period, the number of times of switching by the switch means is reduced and heat generation can be reduced. And since the width of the settling range is narrowed from the middle of the constant current control period to the end point, the variation in the current flowing through the solenoid valve at the end of the constant current control period is reduced, and the variation in the timing at which the solenoid valve closes Variations in the solenoid valve opening period are reduced.

  According to a second aspect of the present invention, when the constant current control period is started, the changing means acquires the switching period of the switch means, and the switching period is at least one cycle before the end of the constant current control period. Narrow the width of the settling range at According to this configuration, the time point for changing the width of the settling range is set on the basis of the end point of the constant current control period, so that a period in which the width of the settling range is narrow is reduced to the minimum necessary to reduce variation in the valve opening period. It is possible to secure the other period as a period in which the width of the settling range is wide in order to reduce heat generation. Further, since the time of one or more switching cycles is secured from the change of the width of the settling range to the end of the constant current control period, the current can be set within the new settling range during this period.

  According to a third aspect of the present invention, when the constant current control period is started, the changing means narrows the width of the settling range at a time point that is a predetermined time before the end point of the constant current control period. . According to this configuration, similarly to the means described in claim 2, only a necessary minimum period in which the width of the settling range is narrowed is reduced in order to reduce variation in the valve opening period, and other periods are set in order to reduce heat generation. It can be secured as a period with a wide range.

  According to the fourth aspect of the present invention, the temperature detecting means for detecting the temperature of the electromagnetic valve driving device is provided. The changing unit narrows the width of the settling range on condition that the detected temperature detected by the temperature detecting unit is lower than the specified temperature. According to this configuration, in the overheated state where the detected temperature is equal to or higher than the specified temperature, it is possible to enhance the heat generation reduction effect.

  According to the fifth aspect of the invention, the operation state detection means is provided for detecting the operation state of the peripheral device that is electromagnetically or electrostatically coupled to the electromagnetic valve driving device. The changing means narrows the width of the settling range on condition that the operation state detecting means detects that the peripheral device is not operating. According to this configuration, since the width of the settling range is kept wide during the operation of the peripheral device, the number of switching operations does not increase, and the electromagnetic valve drive device to the peripheral device by electromagnetic or electrostatic coupling. Intrusion noise can be reduced.

The block diagram of the solenoid valve drive device which shows 1st Embodiment Waveform diagram when driving a solenoid valve Flow chart of constant current control (A) is a drive current waveform when the hysteresis width is narrowed in the middle of the constant current control period, and (b) is a diagram showing a drive current waveform when a constant hysteresis width is used. FIG. 1 equivalent diagram showing the second embodiment 3 equivalent figure FIG. 1 equivalent view showing the third embodiment 3 equivalent figure

In each embodiment, substantially the same parts are denoted by the same reference numerals and description thereof is omitted.
(First embodiment)
A first embodiment will be described with reference to FIGS. A fuel injection control device for a vehicle drives an injector to control fuel injection into each cylinder of the engine. This fuel injection control device includes a solenoid valve driving device 10 shown in FIG. For example, in the case of a two-cylinder engine, when the electromagnetic valve driving device 10 receives an opening / closing command by a drive signal TQ, the electromagnetic valve driving device 10 controls the current flowing through the electromagnetic solenoid type electromagnetic valves 11, 12 included in each injector to control the electromagnetic valves 11, 12. Open / close drive.

  The solenoid valves 11 and 12 include solenoids 11s and 12s, respectively. When the solenoids 11s and 12s are energized, the valve body is displaced from the valve closing position to the valve opening position against the biasing force of the return spring, and fuel injection is performed. When the solenoid is de-energized, the valve body is returned to the closed position by the urging force of the return spring, and the fuel injection is stopped.

  The electromagnetic valve drive device 10 includes a microcomputer 13, a drive control unit 14, a boost power supply unit 15, a discharge driver 16, a constant current driver 17, selection drivers 18, 19, a buffer circuit 20, a current detection resistor 21, and diodes 22-25. ing. The microcomputer 13 controls the drive control unit 14. The current detection resistor 21 corresponds to current detection means, and one end thereof is connected to the ground.

  A battery voltage VB is supplied to the power supply terminal Pd of the electromagnetic valve driving device 10, and solenoids 11s and 12s are connected between the output terminal Pc and the output terminals Pa and Pb, respectively. The discharge driver 16, the constant current driver 17 and the selection drivers 18 and 19 provided in the energization path to the solenoid valves 11 and 12 are constituted by switch means such as MOS transistors.

  In order to open the solenoid valve 11 or 12 at high speed immediately after the start of driving, the boost power supply unit 15 generates a boost voltage Vp for allowing a discharge current to flow through the solenoid valves 11 and 12. Between the power supply terminal Pd and the ground, a boosting coil 26, a MOS transistor 27 as a boosting driver, and a current detection resistor 28 are connected in series. Further, a diode 29 and a capacitor 30 are connected in series between the drain and source of the MOS transistor 27, and the common connection point is an output node of the boost power supply unit 15.

  A voltage dividing circuit including resistors 31 and 32 divides the boosted voltage Vp and outputs a detected boosted voltage. The boost control unit 33 in the drive control unit 14 drives the MOS transistor 27 on when the current flowing through the current detection resistor 28 reaches the lower limit current value so that the detected boost voltage is boosted to the target boost voltage. When the value is reached, the MOS transistor 27 is driven off. As a result, the energy accumulated in the coil 26 is transferred to the capacitor 30 through the diode 29, and the boosting operation is performed.

  The selection drivers 18 and 19 are provided between the output terminals Pa and Pb and the current detection resistor 21, respectively. For each of the electromagnetic valves 11 and 12, the microcomputer 13 outputs a drive signal TQ having an H level period for instructing valve opening and an L level period for instructing valve closing. The cylinder selection control unit 34 in the drive control unit 14 selects one of the electromagnetic valves 11 and 12 to be energized based on the drive signal TQ, and the drive signal TQ is in the H level (hereinafter referred to as drive). The selection driver 18 or 19 provided for the solenoid valve is turned on. The diodes 23 and 24 provided between the output terminals Pa and Pb and the output node of the boost power supply unit 15 allow the current flowing in the solenoids 11s and 12s to the capacitor 30 when the selection drivers 18 and 19 are turned off. Acts to reflux.

  The discharge driver 16 is provided between the output node of the boost power supply unit 15 and the output terminal Pc. The discharge controller 35 in the drive controller 14 turns on the discharge driver 16 when the drive signal TQ becomes H level, and turns off when the drive current of the solenoid valve detected by the current detection resistor 21 reaches the target discharge current Id. To drive. A period during which the discharge driver 16 is driven ON is referred to as a discharge period.

  The constant current driver 17 is provided between the power supply terminal Pd and the output terminal Pc. Between the constant current driver 17 and the output terminal Pc, a diode 25 for preventing a backflow from the boost power supply unit 15 to the power supply terminal Pd is provided. The constant current control unit 36 in the drive control unit 14 drives the solenoid valves 11 and 12 by turning on and off the constant current driver 17 during the constant current control period after the discharge period has elapsed and until the drive period ends. It is a control means which controls so that the fixed drive current for maintaining a valve opening state may be sent through solenoid 11s, 12s.

  The constant current control unit 36 includes a differential amplifier 37, D / A converters 38 and 39, hysteresis comparators 40 and 41, a multiplexer 42, and an output unit 43. The hysteresis comparators 40 and 41 are composed of comparators 40a and 41a and resistors 40b and 41b, respectively. The microcomputer 13 outputs a threshold signal composed of a digital value from the output port, and the D / A converters 38 and 39 convert the threshold signal into a threshold signal composed of an analog value. The differential amplifier 37 amplifies and outputs a detection signal generated in the current detection resistor 21 by the drive current flowing through the solenoid valves 11 and 12.

The hysteresis comparators 40 and 41 compare the threshold signals Vt1 and Vt2 converted by the D / A converters 38 and 39, respectively, with the detection signal Vi output from the differential amplifier 37. Here, if the resistance value of the resistor 40b is R1, the output resistance of the D / A converter 38 is R3, and the output voltage range of the comparator 40a is Vmin to Vmax, the lower limit threshold value Vt1L of the hysteresis comparator 40, the upper limit threshold value. The value Vt1H and the hysteresis width ΔH1 are the expressions (1), (2), and (3). Vt1L = Vt1 + (Vmin−Vt1) × R3 / (R1 + R3) (1)
Vt1H = Vt1 + (Vmax−Vt1) × R3 / (R1 + R3) (2)
ΔH1 = Vt1H−Vt1L = (Vmax−Vmin) × R3 / (R1 + R3) (3)

Similarly, if the resistance value of the resistor 41b is R2, the output resistance of the D / A converter 39 is R4, and the output voltage range of the comparator 41a is Vmin to Vmax, the lower limit threshold Vt2L of the hysteresis comparator 41, the upper limit threshold. The value Vt2H and the hysteresis width ΔH2 are the expressions (4), (5), and (6).
Vt2L = Vt2 + (Vmin−Vt2) × R4 / (R2 + R4) (4)
Vt2H = Vt2 + (Vmax−Vt2) × R4 / (R2 + R4) (5)
ΔH2 = Vt2H−Vt2L = (Vmax−Vmin) × R4 / (R2 + R4) (6)

Since R1 <R2 and R3 = R4 are set, ΔH1 and ΔH2 are in the relationship of equation (7).
ΔH1> ΔH2 (7)

  Here, the hysteresis range sandwiched between the lower limit threshold value Vt1L and the upper limit threshold value Vt1H and the hysteresis range sandwiched between the lower limit threshold value Vt2L and the upper limit threshold value Vt2H correspond to the settling range, and the hysteresis width ΔH1. And ΔH2 correspond to the width of the settling range. The current values corresponding to the lower threshold values Vt1L and Vt2L are set to values larger than the valve closing current value Ic at which the solenoid valves 11 and 12 are started to close.

  The multiplexer 42 selects the output signal of the hysteresis comparator 40 when the selection signal supplied from the microcomputer 13 is at the L level and supplies it to the output unit 43, and selects the output signal of the hysteresis comparator 41 when the selection signal is at the H level. To the output unit 43. The output unit 43 outputs a gate voltage to the constant current driver 17 based on the output signal of the multiplexer 42.

  The buffer circuit 20 generates a monitor signal obtained by converting the level of the gate voltage of the constant current driver 17 using a comparator or the like. The microcomputer 13 inputs this monitor signal from the timer input port. The microcomputer 13 obtains the switching cycle of the constant current driver 17 using the built-in timer, and changes the narrowing width from ΔH1 to ΔH2 at a time point one cycle before the switching cycle with reference to the end point of the constant current control period. Function as.

  Next, the operation when the microcomputer 13 outputs the drive signal TQ and the drive control unit 14 controls the drive of the electromagnetic valve 11 will be described with reference to FIGS. FIG. 2 shows waveforms of the drive signal TQ output from the microcomputer 13, the monitor signal input to the port, and the drive current of the solenoid valve 11 (current flowing through the solenoid 11s).

  When the microcomputer 13 outputs an H level drive signal TQ (time t1), the cylinder selection control unit 34 turns on the selection driver 18 provided in the energization path to the solenoid valve 11, and the discharge control unit 35 outputs the discharge driver 16. Drive on. The constant current driver 17 is turned off until the discharge period ends. As a result, the boosted voltage Vp is applied to the solenoid 11s, and the drive current increases rapidly. When the drive current reaches the target discharge current Id (time t2), the discharge control unit 35 drives the discharge driver 16 off.

  The microcomputer 13 and the constant current control unit 36 drive the constant current driver 17 on and off during the period from the end of the discharge period to the end of the drive period (time t2 to t7). Constant current control is performed so as to be within a settling range sandwiched between threshold values. As shown in FIG. 3, the microcomputer 13 first outputs the threshold signal Vt1 and outputs an L level selection signal (step S1).

  As a result, the constant current control unit 36 drives the constant current driver 17 on when the detection signal Vi corresponding to the drive current is equal to or lower than the lower limit threshold value Vt1L, and when the detection signal Vi becomes equal to or higher than the upper limit threshold value Vt1H. The driver 17 is driven off. As a result, the drive current of the solenoid valve 11 is controlled within a relatively large hysteresis width ΔH1 (settling range) sandwiched between the lower limit threshold value Vt1L and the upper limit threshold value Vt1H.

  The microcomputer 13 inputs the monitor signal input to the port to the built-in timer, and measures the switching periods T1, T2,... Of the constant current driver 17 for N periods (step S2; times t3 to t5). Then, an average switching period Tm is calculated from the N switching periods Tn (n = 1,..., N) (step S3). The microcomputer 13 calculates a change time Tc from the start of the drive period to the time when the hysteresis width is reduced from ΔH1 to ΔH2 by subtracting the average switching period Tm from the time TTQ of the drive period (step S4).

  If the microcomputer 13 determines that the change time Tc has elapsed (step S5; YES) (time t6), the microcomputer 13 outputs the threshold signal Vt2 instead of the threshold signal Vt1, and outputs an H level selection signal. (Step S6). The constant current control unit 36 continues the hysteresis control until the drive signal TQ returns to the L level (time t7). The threshold signals Vt1 and Vt2 are determined so that the drive current (average value) is equal to or greater than the holding current required to keep the solenoid valve 11 open.

  FIG. 4A shows an enlarged drive current of the solenoid valve in the present embodiment. The waveform indicated by the solid line is when the drive current flowing when the drive period ends is maximum, and the waveform indicated by the broken line is when the drive current flowing when the drive period ends is minimum. Since one period of the switching period when the hysteresis width is ΔH1 is secured from the time when the hysteresis width is changed until the end of the driving period, the driving current is settled within the hysteresis width ΔH2 at the end of the driving period. Yes.

  Since the hysteresis width ΔH2 at the end of the drive period is narrow, regardless of the magnitude of the drive current flowing at the end of the drive period, the time until the drive current becomes equal to or less than the valve closing current value Ic after the drive period ends. The maximum deviation is as small as Δtd1. On the other hand, FIG. 4B shows a drive current waveform of a conventional configuration. Since the drive current is controlled within the hysteresis width ΔH1 (> ΔH2), the time lag until the drive current becomes equal to or less than the valve closing current value Ic after the end of the drive period is as large as Δtd2. In order to reduce this deviation, the hysteresis width may be set to ΔH2 in the constant current control period. However, the number of times of switching increases and heat generation increases. That is, in the conventional configuration, it is not possible to reduce both the heat generation and the variation in the valve opening period every time the solenoid valve is driven.

  As described above, the solenoid valve drive device 10 of the present embodiment increases the drive current at high speed during the discharge period, and then narrows the hysteresis width from ΔH1 to ΔH2 during the constant current control period. Thus, the hysteresis width is set to be relatively wide until the middle of the constant current control period, and the number of times of switching by the constant current driver 17 is reduced, so that switching loss, that is, heat generation of the electromagnetic valve driving device 10 can be reduced.

  Since the hysteresis width is narrowed from the middle of the constant current control period to the end point, the variation in the current flowing through the solenoid valves 11 and 12 at the end of the drive period is reduced, and the timing at which the solenoid valves 11 and 12 are closed. Variation, that is, variation in the valve opening period can be reduced. As a result, the accuracy of the injection amount is increased. That is, it is possible to reduce both the heat generation and the variation in the valve opening period each time the electromagnetic valve is driven once.

  The microcomputer 13 sets the hysteresis width change time with reference to the end of the drive period, that is, the end of the constant current control period, so that a minimum period of the hysteresis width can be secured as much as necessary, and heat generation and valve opening The variation in the period can be reduced in a balanced manner. In the present embodiment, the time during which the hysteresis width is narrowed is secured for one period of the average switching period Tm when the hysteresis width is wide, so that the drive current is within the narrow hysteresis width after the change by the end of the drive period. Can be settled.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS. The electromagnetic valve driving device 10 includes a temperature detection circuit 44 that detects the temperature of the electromagnetic valve driving device 10, particularly the temperature of the constant current driver 17. The temperature detection circuit 44 is configured by a series circuit of a resistor 45 and a thermistor 46, and outputs a temperature signal corresponding to the temperature detected by the thermistor 46. The microcomputer 13 receives the temperature signal and performs A / D conversion to obtain the detected temperature.

  The microcomputer 13 executes the constant current control shown in FIG. This control is different from the constant current control shown in FIG. 3 in that steps S11 and S12 are executed between step S1 and step S2. When detecting the temperature in step S11, the microcomputer 13 determines whether or not the detected temperature is lower than the threshold temperature in step S12. The threshold temperature is a temperature at which the constant current driver 17 is determined to be in an overheated state. If the detected temperature is lower than the threshold temperature, the microcomputer 13 executes the processing from step S2 to S6 described in the first embodiment.

  On the other hand, when the detected temperature is equal to or higher than the threshold temperature, the microcomputer 13 does not execute the change control for narrowing the hysteresis width in order to suppress the heat generation of the constant current driver 17, and only the hysteresis width ΔH1 until the drive period ends. Is used to control the constant current. According to the present embodiment, it is possible to increase the effect of reducing heat generation when an overheating state is detected.

(Third embodiment)
Next, a third embodiment will be described with reference to FIGS. The vehicle is equipped with peripheral devices for the electromagnetic valve driving device 10, such as a radio, a television, and a car navigation device. Some of these peripheral devices are electromagnetically or electrostatically coupled to the electromagnetic valve driving device 10 via an antenna, a vehicle body, a harness or the like. When each driver of the solenoid valve driving device 10 is switched, switching noise enters the connected peripheral device.

  For example, when the radio receiver 47 is mounted on a vehicle and power is supplied to the radio receiver 47 via the switch 48, the electromagnetic valve driving device 10 includes a buffer circuit 49 that detects the operating state of the radio receiver 47. (Operating state detecting means). The resistor 50 is a pull-down resistor for fixing the input voltage of the buffer circuit 49 when the switch 48 is turned off.

  The microcomputer 13 executes the constant current control shown in FIG. This control is different from the constant current control shown in FIG. 3 in that steps S21 and S22 are executed between step S1 and step S2. In step S21, the microcomputer 13 detects the operating state (power on / off state) of the radio receiver 47, and determines whether the radio receiver 47 is operating (power on / off) in step S22. . When the radio receiver 47 is not operating, the microcomputer 13 executes the processing from steps S2 to S6 described in the first embodiment.

  On the other hand, when the radio receiver 47 is in operation, the microcomputer 13 does not execute the change control for narrowing the hysteresis width in order to reduce the intrusion of switching noise into the radio receiver 47, and the drive period ends. Constant current control using only the hysteresis width ΔH1. According to the present embodiment, during the operation of the radio receiver 47, the number of switching times of the constant current driver 17 is reduced, so that the electromagnetic valve driving device 10 enters the radio receiver 47 by electromagnetic or electrostatic coupling. Noise can be reduced.

(Other embodiments)
As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to embodiment mentioned above, A various deformation | transformation and expansion | extension can be performed within the range which does not deviate from the summary of invention.

The solenoid valve drive device 10 can be applied to devices other than the fuel injection control device.
The microcomputer 13 changes the hysteresis width by setting the threshold signal to Vt1 or Vt2. As shown in the equations (1), (2), (4) and (5), when the threshold signal is changed, both the upper threshold and the lower threshold change. Instead, the hysteresis width may be changed by changing only one of the upper threshold and the lower threshold in each embodiment.

  In each embodiment, the timing for narrowing the hysteresis width may be any time as long as it is in the middle of the constant current control period. In this case, it is preferable that the time point is one cycle or more before the switching cycle when the hysteresis width is ΔH1, with reference to the end point of the constant current control period.

In each embodiment, the buffer circuit 20 is omitted, and the microcomputer 13 skips the processes of steps S2 and S3, and sets the hysteresis width at a time point that is a predetermined time before the end point of the constant current control period. It may be narrowed. That is, in step S4, the microcomputer 13 may calculate the change time Tc by subtracting a predetermined time Ts from the drive period time TTQ.
It is good also as a structure which combined 2nd, 3rd embodiment.

  In the drawing, 10 is a solenoid valve drive device, 11 and 12 are solenoid valves, 13 is a microcomputer (changing means), 17 is a constant current driver (switch means), 21 is a current detection resistor (current detection means), and 36 is a constant current. A control unit (control unit), 44 is a temperature detection circuit (temperature detection unit), 47 is a radio receiver (peripheral device), and 49 is a buffer circuit (operation state detection unit).

Claims (5)

In the electromagnetic valve drive device (10) for controlling the current flowing through the electromagnetic valves (11, 12) upon opening / closing commands to drive the electromagnetic valves to open / close,
Switch means (17) provided in the energization path to the solenoid valve;
Current detection means (21) for detecting a current flowing through the solenoid valve;
When the detected current value detected by the current detecting means is less than or equal to a lower threshold value, the switch means is turned on, and when the detected current value is greater than or equal to the upper threshold value, the switch means is driven off, Control means (36) for controlling the current flowing through the solenoid valve within a settling range sandwiched between the lower threshold and the upper threshold;
Changing the lower limit threshold value and / or the upper limit threshold value to narrow the width of the settling range during the constant current control period in which the control means receives the opening / closing command and executes the constant current control And a means (13).   When the constant current control period is started, the changing unit obtains a switching cycle of the switch unit, and the settling is performed at a time one cycle or more before the switching cycle with reference to an end point of the constant current control period. The electromagnetic valve driving device according to claim 1, wherein the range is narrowed.   When the constant current control period is started, the changing unit narrows the width of the settling range at a time point that is a predetermined time before the end point of the constant current control period. Item 2. The electromagnetic valve driving device according to Item 1. Temperature detecting means (44) for detecting the temperature of the electromagnetic valve driving device;
The electromagnetic wave according to any one of claims 1 to 3, wherein the changing unit narrows the width of the settling range on condition that the detected temperature detected by the temperature detecting unit is lower than a specified temperature. Valve drive device. An operation state detecting means (49) for detecting an operation state of a peripheral device (47) electromagnetically or electrostatically coupled to the electromagnetic valve driving device;
The change means narrows the width of the settling range on condition that the operation state detection means detects that the peripheral device is not operating. The electromagnetic valve driving device according to Item.

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