JP6926685B2 - Injection control device - Google Patents

Description

The present invention relates to an injection control device that controls the drive of an injection valve that injects fuel into an internal combustion engine.

In recent years, due to stricter exhaust regulations and the like, injection control devices are required to have more precise system control than before. Further, in recent years, the number of vehicles equipped with a start control mechanism (idle stop mechanism) such as start and stop has been increasing, and as an injection control device, it is possible to cope with a drop in power supply voltage at the time of restart such as cranking. It has been demanded.

In such an injection control device, two different voltages, that is, a battery voltage which is a DC voltage given from an in-vehicle battery and a boosted voltage obtained by boosting the battery voltage can be applied to the injection valve. It has become. Then, in order to apply each of these voltages, the injection control device is provided with a switching element such as a MOSFET.

In such a configuration, when the power supply voltage, that is, the battery voltage drops due to cranking or the like, the level of the gate signal for driving the MOSFET also drops. When the level of the gate signal decreases, the MOSFET is turned on with its on-resistance high, its calorific value increases, and its temperature rises. In particular, when a boosting voltage is applied to the injection valve as in the injection control device described above, the MOSFET is driven on with a very high drain-source voltage and a high on-resistance. , The calorific value, and eventually the temperature may rise further. A MOSFET may fail if its temperature rises above the guaranteed temperature.

Conventionally, various measures have been devised to reduce heat generation in transistors such as MOSFETs. For example, Patent Document 1 provides a thermistor that detects the temperature of a transistor that drives a load, and performs protection control when it is determined that the transistor is in an overheated state based on the temperature detected by the thermistor. It is disclosed. Further, Patent Document 2 discloses a technique of calculating the calorific value of MOSFT and performing protection control based on the calculated calorific value.

Japanese Unexamined Patent Publication No. 2008-035684 JP-A-2009-219286

However, it is difficult to accurately detect the actual temperature of the MOSFET by the method of detecting the temperature using a thermistor as in the technique described in Patent Document 1. Further, in the technique described in Patent Document 2, it is a single power supply, and it is not assumed that the power supply voltage is lowered. Therefore, the technique described in Patent Document 2 cannot be applied to an injection control device in which there are two types of power sources and the battery voltage may be significantly lowered due to cranking or the like.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an injection control device capable of suppressing an excessive rise in the temperature of a switching element for driving an injection valve. ..

The injection control device (1) according to claim 1 controls the drive of injection valves (2, 3) that inject fuel into an internal combustion engine, and controls the drive of the first upstream switching element (Q1) and the second upstream side. It includes a switching element (Q2), downstream switching elements (Q3, Q4), a current detection unit (8A), a voltage detection unit (8B), and a drive control unit (7).

The first upstream switching element is provided on the upstream side of the power supply path from the DC power supply line to which the DC voltage supplied from the DC power supply is supplied to the injection valve. The second upstream switching element is provided on the upstream side of the feeding path from the boosted power supply line to the injection valve to which the boosted voltage obtained by boosting the DC voltage is supplied. The downstream switching element is commonly provided on the downstream side of each feeding path. The current detection unit detects the drive current flowing through the downstream switching element. The voltage detection unit detects the voltage between the terminals of the downstream switching element. The drive control unit drives the injection valve by turning on one of the first upstream switching element and the second upstream switching element and turning on the downstream switching element.

In the above configuration, if the detection value of the drive current flowing through the downstream switching element detected by the current detection unit and the detection value of the voltage between the terminals of the downstream switching element detected by the voltage detection unit are used, the downstream switching It is possible to obtain the amount of heat when the element is driven. Then, by integrating the obtained amount of heat, it is possible to accurately estimate the temperature of the downstream switching element. Therefore, the drive control unit estimates the temperature of the downstream switching element based on the detection value of the current detection unit and the detection value of the voltage detection unit, and determines that the estimated temperature exceeds a predetermined threshold temperature. Stops the on drive of the side switching element.

In this way, the actual temperature of the downstream switching element can be estimated accurately. Then, in the above configuration, when it is determined that the estimated temperature of the downstream switching element exceeds the threshold temperature, the on drive of the downstream switching element is stopped. In this case, the injection control device further includes a storage unit (5) in which the transient thermal resistance of the downstream switching element is stored. The drive control unit estimates the junction temperature of the downstream switching element based on the detection value of the current detection unit, the detection value of the voltage detection unit, and the transient thermal resistance, and determines that the estimated junction temperature exceeds the threshold temperature. , Stop the on drive of the downstream switching element. Further, the drive control unit determines that the junction temperature exceeds the threshold temperature, stops the on-drive of the downstream switching element, and then uses the transient thermal resistance to reduce the junction temperature of the downstream switching element to less than the threshold temperature. The time required for the process is estimated, and when the estimated time elapses, the on-drive stop of the downstream switching element is released. According to the above configuration, it is possible to obtain an excellent effect that it is possible to suppress an excessive rise in the temperature of the downstream switching element when the DC voltage drops.

The figure which shows typically the structure of the injection control device and the injector which concerns on one Embodiment. The figure which shows typically the content of the control by the microcomputer which concerns on one Embodiment Timing chart schematically showing the operating state of each part according to one embodiment

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The injection control device 1 shown in FIG. 1 is provided in an engine ECU which is one of a plurality of electronic control devices (hereinafter, referred to as ECUs) mounted on a vehicle. The engine ECU integrally controls various actuators based on various sensor signals in various operating states of the vehicle, and realizes operation in the optimum engine state.

The injection control device 1 controls the drive of an injector that injects and supplies fuel compressed to a high pressure into the cylinder of an engine corresponding to an internal combustion engine mounted on a vehicle, for example. The injection control device 1 controls the energization current (hereinafter, also referred to as a drive current) to the solenoid valves 2 and 3 of the solenoid solenoid type included in the injector to open and close the solenoid valves 2 and 3. Although only two solenoid valves 2 and 3 are shown in FIG. 1, in reality, there are a number of solenoid valves corresponding to the number of cylinders of the engine, and the injection control device 1 has a plurality of them. A configuration for driving the solenoid valve of the above is provided. The solenoid valves 2 and 3 correspond to injection valves.

A battery voltage VB output from an in-vehicle battery (not shown) is supplied to the injection control device 1. The in-vehicle battery corresponds to a DC power supply, and the battery voltage VB corresponds to a DC voltage. A solenoid valve 2 is connected between the terminals P1 and P2 of the injection control device 1, and a solenoid valve 3 is connected between the terminals P3 and P4.

In this case, the injection control device 1 performs peak current control for supplying a peak current to the solenoid valves 2 and 3 at the start of the set drive period, and promptly opens the solenoid valves 2 and 3. After that, the injection control device 1 performs constant current control until the end of the drive period, and keeps the solenoid valves 2 and 3 in the open state.

The solenoid valves 2 and 3 are provided with a solenoid, and when the solenoid is energized, the valve body is displaced from the valve opening position to the valve opening position against the urging force of the return spring, and fuel injection is performed. When the solenoid is cut off, the valve body returns to the closed position due to the urging force of the return spring, and fuel injection is stopped. The solenoid valves 2 and 3 are driven and controlled so as not to be opened at the same time.

The injection control device 1 includes a signal input unit 4, a non-volatile memory 5, a thermistor 6, a microcomputer 7, a MOS status monitor circuit 8, a MOS drive IC 9, a drive circuit 10, and the like. The signal input unit 4 is provided with a comparator or the like, inputs a periodically changing input signal S1 output from a magnet pickup coil or the like, and converts the input signal S1 into a signal that can be captured by the microcomputer 7. Output.

The non-volatile memory 5 stores data such as transient thermal resistance information which is information on transient thermal resistance corresponding to the MOSFET used in the drive circuit 10 and various threshold values described later. The non-volatile memory 5 corresponds to a storage unit. The thermistor 6 detects the internal temperature of the ECU provided with the injection control device 1 and outputs a temperature detection signal S2 representing the detected value. The thermistor 6 corresponds to a temperature detection unit that detects the temperature inside the device. The MOS state monitor circuit 8 outputs a MOS state signal S3A representing a detected value of the drive current and a MOS state signal S3B representing a detected value of the voltage between terminals of the MOSFET used in the drive circuit 10.

The microcomputer 7 has a CPU, a ROM, a RAM, an A / D converter, and the like, and the CPU controls the overall operation of the apparatus by executing a program stored in the ROM and the like. Based on the output signal of the signal input unit 4, the MOS state signals S3A, S3B, and the like, the microcomputer 7 of the MOS drive IC 9 and eventually the drive circuit 10 so that the drive current flowing through the solenoid valves 2 and 3 becomes a desired current value. Control the operation. When the injector drive is requested, the microcomputer 7 has a drive request signal for commanding opening and closing of each of the solenoid valves 2 and 3, a required current value for commanding a current value to be passed through the solenoid valves 2 and 3, and the like. The MOS drive signal S4 representing the above is transmitted to the MOS drive IC 9.

The MOS drive IC 9 controls the operation of the drive circuit 10 based on the MOS drive signal S4 or the like transmitted from the microcomputer 7. Specifically, the MOS drive IC 9 controls the operation of the drive circuit 10 so that a current based on the required current value is supplied to the solenoid valves 2 and 3 corresponding to the injector having a drive request.

The drive circuit 10 includes transistors Q1 to Q4, diodes D1 and D2, shunt resistors R1 and R2, amplifiers 11 and 12, which are N-channel MOSFETs. The drain of the transistor Q1 is connected to the DC power supply line L1 to which the battery voltage VB is supplied, and its source is connected to the terminals P1 and P3 via the diode D1 in the forward direction. The transistor Q1 is provided on the upstream side of the feeding path from the DC power supply line L1 to the solenoid valves 2 and 3, and corresponds to the first upstream switching element.

The drain of the transistor Q2 is connected to the boost power supply line L2 to which the boost voltage VP is supplied, and its source is connected to the terminals P1 and P3. The transistor Q2 corresponds to a second upstream switching element provided on the upstream side of the feeding path from the step-up power supply line L2 to the solenoid valves 2 and 3.

The cathode of the diode D2 is connected to the terminals P1 and P3, and its anode is connected to the ground wire L3 to which the ground potential (0V) which is the reference potential of the circuit is given. The boost voltage VP is for passing the above-mentioned peak current through the solenoid valves 2 and 3, and is generated by a boost circuit (not shown). The booster circuit is configured as a booster type switching power supply circuit, and generates a booster voltage VP by boosting the battery voltage VB.

The drain of the transistor Q3 is connected to the terminal P2, and its source is connected to the ground wire L3 via the shunt resistor R1. The drain of the transistor Q4 is connected to the terminal P4, and its source is connected to the ground line L3 via the shunt resistor R2. The transistors Q3 and Q4 correspond to downstream switching elements commonly provided on the downstream side of each of the above feeding paths. Gate signals Sg1 to Sg4 output from the MOS drive IC 9 are given to each gate of the transistors Q1 to Q4, whereby the drive of the transistors Q1 to Q4 is controlled.

The terminal voltages of the shunt resistors R1 and R2 are input to the amplifiers 11 and 12, respectively. The amplifiers 11 and 12 amplify the voltage between the terminals of the shunt resistors R1 and R2, and their output voltages are given to the MOS state monitor circuit 8. The MOS state monitor circuit 8 detects each drive current flowing through the transistors Q3 and Q4 based on the output voltages of the amplifiers 11 and 12.

Further, the MOS state monitor circuit 8 is given a voltage of each drain of the transistors Q3 and Q4 and a voltage of each source. The MOS state monitor circuit 8 detects the drain-source voltage (hereinafter referred to as voltage VDS), which is the voltage between the terminals of the transistors Q3 and Q4, based on these voltages.

As described above, the MOS state monitor circuit 8 has a function as a current detection unit 8A for detecting the drive current flowing through the transistors Q3 and Q4, and also as a voltage detection unit 8B for detecting the voltage VDS of the transistors Q3 and Q4. Has.

The transistor Q1 opens and closes a path for applying the battery voltage VB to the solenoid valves 2 and 3, and is also referred to as a constant current MOS below. Further, the transistor Q2 opens and closes a path for supplying the boost voltage VP to the solenoid valves 2 and 3, and is also referred to as a discharge MOS below. Further, the transistors Q3 and Q4 open and close between the downstream terminals of the solenoid valves 2 and 3 and the ground wire L3, and hereinafter, these are collectively referred to as a cylinder MOS.

The MOS drive IC 9 selects one that energizes from the solenoid valves 2 and 3 based on the MOS drive signal S4 given from the microcomputer 7, and the period in which the drive request signal commands the valve opening (hereinafter, referred to as a drive period). ), The cylinder MOS provided corresponding to the solenoid valve is driven on. Then, the MOS drive IC 9 drives the discharge MOS on during the period when the peak current control is performed. Further, the MOS drive IC 9 drives the constant current MOS on and off during the period during which the constant current control is performed.

Next, the operation of the above configuration will be described.
In the above configuration, the microcomputer 7 controls the drive of the solenoid valves 2 and 3 by performing peak current control and constant current control, and corresponds to a drive control unit. In this way, the microcomputer 7 corresponding to the drive control unit executes the control as shown in FIG. 2 at predetermined intervals during the drive period for driving the solenoid valves 2 and 3.

First, in step S100, the internal temperature of the ECU is measured based on the temperature detection signal S2. In step S110, the discharge MOS and the cylinder MOS are driven on, so that the solenoid valves 2 and 3 are driven. At this time, the measurement of the drive current flowing through the cylinder MOS and the measurement of the voltage VDS of the cylinder MOS are also started. It should be noted that these measurements are executed at least during the period when the peak current control is performed, that is, during the period when the transistor Q2 is on.

In step S120, it is determined whether or not the drive current and the voltage VDS are equal to or less than a predetermined threshold value based on the MOS state signals S3A and S3B. Specifically, it is determined whether or not the value of the drive current and the value of the voltage VDS are within the region where the cylinder MOS can safely operate (safe operation region). Each threshold value used at this time is set based on the characteristics of the MOSFETs (transistors Q3 and Q4) used as the cylinder MOS, and is stored in the non-volatile memory 5 in advance. When the internal temperature of the ECU measured in step S100 is a predetermined determination temperature, for example, room temperature (for example, 25 degrees) or higher, derating is performed based on the measured value of the internal temperature.

If it is determined that the drive current and the voltage VDS are equal to or less than the threshold value, that is, if “YES” in step S120, the process proceeds to step S130. In step S130, the amount of heat at the time of driving the cylinder MOS is obtained from the drive current and voltage VDS obtained based on the MOS state signals S3A and S3B. Then, the junction temperature of the cylinder MOS is estimated based on the integrated heat amount, the transient thermal resistance information stored in the non-volatile memory 5, the internal temperature of the ECU measured in step S100, and the like.

In step S140, it is determined whether or not the junction temperature of the cylinder MOS estimated in step S130 exceeds a predetermined threshold temperature. The threshold temperature used at this time is set based on the characteristics of the MOSFETs (transistors Q3 and Q4) used as the cylinder MOS, and is stored in the non-volatile memory 5 in advance.

When the junction temperature is equal to or lower than the threshold temperature, that is, when "YES" in step S140, the process ends (end). On the other hand, if it is determined that the drive current and the voltage VDS exceed the threshold value, or if the junction temperature is determined to exceed the threshold temperature, that is, if “NO” in step S120 or S140, the process proceeds to step S150.

In step S150, the on drive of the cylinder MOS is stopped, and the cylinder MOS is turned off. In step S160, the junction temperature of the cylinder MOS is estimated in the same manner as in step S130. In step S170, the junction temperature estimated in step S160 and the transient thermal resistance information stored in the non-volatile memory 5 are used to estimate the time required for the junction temperature of the cylinder MOS to drop below the threshold temperature. NS.

In step S180, it is determined whether or not the required time estimated in step S170 has elapsed. If the required time has not elapsed, that is, if "NO" in step S180, the process returns to step S170. On the other hand, when the required time has elapsed, that is, when "YES" in step S180, the process proceeds to step S190. In step S190, the stop of the on drive of the cylinder MOS is released, and the cylinder MOS can be turned on. After the execution of step S190, the process ends (end).

Subsequently, the operating state of each part when the battery voltage VB is unintentionally lowered due to cranking or the like will be described with reference to FIG. When the battery voltage VB decreases, the levels of the gate signals Sg1 to Sg4 also decrease due to the effect. When the solenoid valves 2 and 3 are driven in such a state, the cylinder MOS is turned on with a high on-resistance, so that the voltage VDS becomes higher than before the battery voltage VB drops.

When the voltage VDS rises, the amount of heat when the cylinder MOS is driven, and thus the estimated value of the junction temperature, rises more than before the battery voltage VB drops. Then, when it is determined that the junction temperature has reached the threshold temperature at time t1, the on-drive of the cylinder MOS is stopped. As a result, the on-drive of the cylinder MOS and, by extension, the drive of the solenoid valves 2 and 3 are stopped.

After the on-drive of the cylinder MOS is stopped in this way, when it is determined that the time required for the junction temperature of the cylinder MOS to drop below the threshold temperature has elapsed, the stop of the on-drive of the cylinder MOS is released. Will be done. As a result, the on-drive of the cylinder MOS and the drive of the solenoid valves 2 and 3 are restarted.

According to the present embodiment described above, the following effects can be obtained.
In the above configuration, by using the detected value of the drive current flowing through the cylinder MOS detected by the MOS state monitor circuit 8 and the detected value of the voltage VDS of the cylinder MOS, it is possible to obtain the amount of heat when the cylinder MOS is driven. be. Then, by integrating the obtained amount of heat, it is possible to accurately estimate the temperature of the cylinder MOS. Therefore, in the present embodiment, the microcomputer 7 estimates the temperature of the cylinder MOS based on the MOS state signals S3A and S3B representing each detected value given from the MOS state monitor circuit 8, and the estimated temperature is a predetermined threshold value. If it is determined that the temperature is exceeded, the on-drive of the cylinder MOS is stopped.

In this way, the actual temperature of the cylinder MOS can be estimated accurately. Then, in the above configuration, when it is determined that the estimated temperature of the cylinder MOS exceeds the threshold temperature, the on-drive of the cylinder MOS is stopped. Therefore, according to the above configuration, it is possible to obtain an excellent effect that an excessive rise in the temperature of the cylinder MOS when the battery voltage VB drops due to cranking or the like can be suppressed and a failure of the cylinder MOS can be prevented. ..

In the injection control device 1, when the peak current control is performed, a voltage substantially equal to the boost voltage VP higher than the battery voltage VB is applied to the drain of the cylinder MOS. In this case, since the voltage VDS of the cylinder MOS is much higher than when the battery voltage VB is applied, the amount of heat generated by the cylinder MOS when the battery voltage VB is lowered and the gate signals Sg1 to Sg4 are lowered is further increased. To rise. Therefore, in the present embodiment, the microcomputer 7 measures the drive current and the voltage VDS at least during the period in which the transistor Q2 interposed upstream of the supply path of the boosted voltage VP is on-driven, and based on the measurement results. The above-mentioned estimation and judgment are performed. Therefore, according to the present embodiment, even when the temperature rise of the cylinder MOS is likely to rise further, the excessive rise can be suppressed.

Further, the microcomputer 7 determines whether or not the cylinder MOS is operating in the safe operating region based on the detected value of the drive current of the cylinder MOS and the detected value of the voltage VDS, and determines that the microcomputer 7 is not operating in the safe operating region. When it is judged, the on drive of the cylinder MOS is stopped. In this way, regardless of whether the temperature of the cylinder MOS (junction temperature) exceeds the threshold temperature, if it is determined that the cylinder MOS is not operating in the safe operating region, the cylinder MOS Since the on-drive of the cylinder is stopped, it is possible to surely prevent the failure of the cylinder MOS.

Further, when the measured value of the internal temperature of the ECU is a temperature equal to or higher than room temperature, the microcomputer 7 performs derating based on the measured value of the internal temperature in determining whether or not the device is operating in the above-mentioned safe operating region. .. The internal temperature of the ECU is not constant and changes from moment to moment. Therefore, in this way, the above-mentioned determination can be made without being affected by the fluctuation of the internal temperature of the ECU, and as a result, the failure of the cylinder MOS can be prevented more reliably.

The non-volatile memory 5 of the injection control device 1 stores information (transient thermal resistance information) regarding the transient thermal resistance corresponding to the MOSFET used as the cylinder MOS. Then, the microcomputer 7 estimates the junction temperature of the cylinder MOS based on the transient thermal resistance information stored in the non-volatile memory 5 in addition to each detected value by the MOS state monitor circuit 8, and the estimated junction temperature is the threshold value. If it is determined that the temperature is exceeded, the on-drive of the cylinder MOS is stopped. In this way, the temperature of the cylinder MOS can be detected with high accuracy. Therefore, as the threshold temperature, for example, a temperature close to the guaranteed temperature of the MOSFET can be set, so that when the battery voltage VB drops, the cylinder MOS is turned on and the solenoid valves 2 and 3 are driven as much as possible. While continuing, it is possible to prevent the failure of the cylinder MOS.

The microcomputer 7 estimates the time required for the junction temperature of the cylinder MOS to drop below the threshold temperature using the transient thermal resistance information stored in the non-volatile memory 5 after the on-drive of the cylinder MOS is stopped. When the estimated time elapses, the on-drive stop of the cylinder MOS is released. In this way, when the on-drive of the cylinder MOS is stopped and the temperature drops below the threshold temperature, the on-drive stop of the cylinder MOS is immediately released and the driving of the solenoid valves 2 and 3 is restarted. can do.

(Other embodiments)
The present invention is not limited to the embodiments described above and shown in the drawings, and can be arbitrarily modified, combined, or extended without departing from the gist thereof.
The transistors Q1 to Q4 are not limited to N-channel MOSFETs, and various types of semiconductor switching elements can be used.
The specific configuration of the current detection unit that detects the drive current flowing through the cylinder MOS and the voltage detection unit that detects the voltage between the terminals of the cylinder MOS does not have to be limited to the configuration shown in FIG. If it has a configuration, it can be changed as appropriate.

In step S120 in FIG. 2, that is, in the process of determining whether or not the cylinder MOS is operating in the safe operation region, derating based on the internal temperature of the ECU may be performed as necessary. Further, the determination process itself in step S120 may be performed as needed, and may be omitted.

Although the present disclosure has been described in accordance with the examples, it is understood that the present disclosure is not limited to the examples and structures. The present disclosure also includes various modifications and modifications within a uniform range. In addition, various combinations and forms, as well as other combinations and forms that include only one element, more, or less, are also within the scope of the present disclosure.

1 ... Injection control device, 2, 3 ... Solenoid valve, 5 ... Non-volatile memory, 6 ... Thermistor, 7 ... Microcomputer, 8A ... Current detector, 8B ... Voltage detector, L1 ... DC power supply line, L2 ... Boost power supply line , Q1 to Q4 ... Transistor.

Claims (3)

An injection control device (1) that controls the drive of injection valves (2, 3) that inject fuel into an internal combustion engine.
A first upstream switching element (Q1) provided on the upstream side of the feeding path from the DC power supply line (L1) to which the DC voltage supplied from the DC power supply is supplied to the injection valve, and
A second upstream switching element (Q2) provided on the upstream side of the feeding path from the boosted power supply line (L2) to which the boosted voltage obtained by boosting the DC voltage is supplied to the injection valve.
Downstream switching elements (Q3, Q4) commonly provided on the downstream side of each feeding path, and
A current detection unit (8A) that detects the drive current flowing through the downstream switching element, and
A voltage detection unit (8B) that detects the voltage between the terminals of the downstream switching element, and
A drive control unit (7) that drives the injection valve by turning on one of the first upstream switching element and the second upstream switching element and turning on the downstream switching element.
With
The drive control unit estimates the temperature of the downstream switching element based on the detection value of the current detection unit and the detection value of the voltage detection unit, and determines that the estimated temperature exceeds a predetermined threshold temperature. , Stop the on drive of the downstream switching element ,
Further, a storage unit (5) in which the transient thermal resistance of the downstream switching element is stored is provided.
The drive control unit estimates the junction temperature of the downstream switching element based on the detection value of the current detection unit, the detection value of the voltage detection unit, and the transient thermal resistance, and the estimated junction temperature is the threshold value. When it is determined that the temperature is exceeded, the on drive of the downstream switching element is stopped, and the temperature is exceeded.
The drive control unit determines that the junction temperature exceeds the threshold temperature, stops the on-drive of the downstream switching element, and then uses the transient thermal resistance to set the junction temperature of the downstream switching element to the threshold. An injection control device that estimates the time required for the temperature to drop below the temperature, and releases the on-drive stop of the downstream switching element when the estimated time elapses. The injection control according to claim 1, wherein the drive control unit makes the determination based on the detection value of the current detection unit and the detection value of the voltage detection unit during the period when the second upstream switching element is on. Device. Further, a temperature detection unit (6) for detecting the temperature inside the device is provided.
Claim 1 or 2 in which the drive control unit makes the determination based on the detection value of the current detection unit and the detection value of the voltage detection unit during a period in which the detection value of the temperature detection unit is equal to or higher than a predetermined determination temperature. The injection control device according to.

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