KR20030038518A - Driving timing control circuit of actuator for valve driving, injector and fuel injection system - Google Patents

Abstract

PURPOSE: To constantly drive an actuator at a desired timing regardless of the variation of electrical characteristics of an actuator itself for valve driving and the variation of electronic part constituting a driving circuit. CONSTITUTION: A drive control signal Vst outputted from a microcomputer 1 is set such that, in the actuator drive timing adjusting circuit 52 for valve driving, leading and trailing are set at respective optional timings by a first semi-fixing resistor 8 and a second semi-fixing resistor 9, respectively. Regardless of the variation of the electrical characteristics of the actuator itself for valve driving and the variation of the electronic parts constituting the driving circuit, energizing to a solenoid 14 is carried out at the desired timing.

Description

Actuator Drive Timing Control Circuit, Injector and Fuel Injector for Valve Drives {DRIVING TIMING CONTROL CIRCUIT OF ACTUATOR FOR VALVE DRIVING, INJECTOR AND FUEL INJECTION SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive circuit, an injector, and a fuel injector of a valve driving actuator used for a fuel injection valve of a fuel injector, and in particular, to a valve driving actuator driving timing aimed at compensating for variations in operating characteristics of an actuator. A regulating circuit, an injector and a fuel injection device.

For example, in a fuel injection device of an internal combustion engine, an electromagnetic valve may be used as an actuator for driving a valve in an injection mechanism, but variations in the electrical characteristics of the solenoid valve itself and the electronic components constituting the drive circuit may be used. It is difficult to avoid the influence on the opening and closing timing of the solenoid valve due to the deviation.

Thus, for example, a time constant circuit for smoothly raising and lowering the driving pulse for opening and closing the solenoid valve is provided in the drive circuit of the solenoid valve, so as to mitigate the influence on the opening and closing timing of the solenoid valve due to variations in components and the like. It is proposed (refer to Unexamined-Japanese-Patent No. 9-280410).

Further, the E ² PROM is mounted in the fuel injection pump, and the function difference data for each fuel injection pump is stored in the E ² PROM, and the operation of the fuel injection pump is performed by a control device provided outside the fuel injection pump. Has been proposed to control the operation of the fuel injection pump according to the function difference data by reading the function difference data stored in the E ² PROM via a communication line when controlling the power supply (Japanese Patent Laid-Open No. 8). -284731 publication).

However, the former technique is suitable for injectors having a relatively low response since the driving pulse signal is gradually moderately raised and lowered, but is not suitable for a so-called common rail fuel injector or the like requiring a high speed response. Regardless of the required responsiveness, there is a demand for a method capable of eliminating the influence on the timing of opening and closing the solenoid valve due to variations in the electrical characteristics of the solenoid valve itself and variations of the electronic components constituting the driving circuit.

In the latter case, in addition to the driving circuit of the solenoid valve, a communication circuit for transmitting the E ² PROM and its data to an external control device is required, which not only leads to the complexity of the device but also to the high cost of the device. There is a problem that measures to secure data reliability by preventing data errors when reading data from a ² PROM by an external control device are required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and a valve drive capable of always driving an actuator at a desired timing regardless of variations in electrical characteristics of the valve driving actuator itself, variations of electronic components constituting the driving circuit, or the like. It is to provide an actuator drive timing adjustment circuit, an injector, and a fuel injection device.

Another object of the present invention is a valve drive that can always open and close the valve at a desired timing, regardless of variations in the electrical characteristics of the solenoid valve itself or variations of the electronic components constituting the drive circuit even when a high speed response is required. It is to provide an actuator drive timing adjustment circuit, an injector, and a fuel injection device.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a circuit diagram showing an example of a circuit configuration when a valve driving actuator drive timing adjustment circuit in an embodiment of the present invention is used for a fuel injection device.

FIG. 2 is a timing diagram for explaining the operation of the valve driving actuator timing adjusting circuit shown in FIG. 1, FIG. 2 (a) is a timing diagram showing an output timing of a control drive signal output from a microcomputer, and FIG. b) is a timing diagram showing the shape of the control drive signal at the input terminal of the inverter used in the valve drive actuator drive timing adjustment circuit shown in FIG. 1, and FIG. Fig. 2 (d) is a timing diagram showing the shape at the output end of the inverter when no delay is performed. Fig. 2 (d) shows the timing at the output end of the inverter when the rise of the drive control signal applied to the valve driving actuator drive timing adjustment circuit is delayed. Fig. 2 (e) is a timing diagram showing the shape of the drive control signal applied to the actuator drive timing adjustment circuit. The timing chart which shows the shape in the output terminal of an inverter in case delaying descent | fall.

Explanation of symbols for the main parts of the drawings

1: microcomputer 8: first semi-fixed resistor

9 second semi-fixed resistor 10 first diode for control circuit

11: diode for second adjustment circuit 51: solenoid drive circuit

52: actuator drive timing adjustment circuit for valve drive

101: injector 102: electronic control unit

In order to achieve the object of the present invention, the valve driving actuator driving timing adjusting circuit according to the present invention comprises a driving circuit configured to conduct electricity to the valve driving actuator via a switch element brought into a conductive state by application of a driving control signal. It is provided in the input terminal, it is configured to be able to adjust the timing of the rise and fall of the drive control signal applied to the switch element.

In such a configuration, since the rise and fall of the drive control signal applied to the switch element is adjusted by the valve drive actuator drive timing adjustment circuit, and the actuator can be driven, variations in the electrical characteristics of the valve drive actuator itself, The actuator can always be driven at a desired timing regardless of the deviation of the electronic components constituting the drive circuit.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

In addition, the member, arrangement | positioning, etc. which are demonstrated below do not limit this invention, It can change in various ways within the meaning of this invention.

First, the structure of the actuator drive timing adjustment circuit for valve drive in the Example of this invention is demonstrated, referring drawings.

The valve drive actuator drive timing adjustment circuit 52 in the embodiment of the present invention is a solenoid of a solenoid valve used as an actuator for valve drive in an injector 101 of a fuel injection device of an internal combustion engine represented by an engine. It is an example provided in the solenoid drive circuit 51 for driving 14, In particular, this valve drive actuator drive timing adjustment circuit 52 is provided in the injector 101 (refer FIG. 1). In addition, in FIG. 1, the electronic control part (notation "ECU" in FIG. 1) which outputs the drive control signal Vst mentioned later to the solenoid drive circuit 51 is shown.

First, the electronic control unit 102 is composed mainly of a well-known and known microcomputer (denoted as "CPU" in FIG. 1) 1, and various signals input from the outside and the electronic control unit 102 are not shown. Based on various data stored in advance in a predetermined data storage area, various calculations, determination processing, and the like for operation control of the engine or control of the fuel injection device are performed, and as will be described later, the solenoid drive The drive control signal Vst is output to the circuit 51. In addition, in FIG. 1, the electronic control part 102 has shown only the circuit wiring of the part which concerns on drive of the solenoid 14. As shown in FIG. As a signal input from the outside to the electronic control unit 102, particularly related to the drive of the solenoid 14 of the injector 101, a signal indicating an accelerator opening degree of an engine (not shown) or an engine speed is shown. There is a corresponding signal, and various signals are input to the electronic control unit 102 from the outside.

In the microcomputer 1 of the electronic control unit 102 in the embodiment of the present invention, the N-channel as the first switch element is output to the first output port (denoted as "P ₁ " in Fig. 1) for outputting a control signal. The gate of one MOS-FET 2 is connected. The power supply voltage V _H is applied to the source of the first MOS-FET 2 by a DC power supply (not shown), while the drain is connected to the cathode of the first protective diode 4 whose anode is connected to ground. It is connected to one end of the solenoid 14 which constitutes an electromagnetic valve (not shown) in the injector 101.

In the embodiment of the present invention, the solenoid drive circuit 51 includes a circuit portion constituted by the first MOS-FET 2 and the first protection diode 4 described above, and a valve drive described below provided in the injector 101. It is comprised by the circuit part comprised centering on the actuator actuator timing adjustment circuit 52 and the 2nd MOS-FET3.

That is, in the injector 101, first, the drain of the second MOS-FET 3 is connected to the other end of the solenoid 14, and the source of the second MOS-FET 3 is connected to the electronic control unit 102. It is connected to the ground terminal (denoted as "GND" in FIG. 1) of the microcomputer 1, and is connected to the ground via the resistor 6 in the electronic control unit 102 (see FIG. 1).

In addition, between the drain and the gate of the second MOS-FET 3, in order to prevent the destruction of the second MOS-FET 3 due to the counter voltage generated in the solenoid 14, the zener diode 7 and the second The protective diode 5 is connected in series. That is, the cathode of the zener diode 7 is connected to the drain of the second MOS-FET 3, the anode of the zener diode 7 is connected to the anode of the second protective diode 5, and this second protective diode The cathode of (5) is connected to the gate of the second MOS-FET 3.

In addition, an actuator drive timing adjustment circuit 52 for valve driving is provided between the gate of the second MOS-FET 3 and the microcomputer 1 of the electronic control unit 102 as described below.

That is, firstly, one end of each of the first and second semi-fixed resistors 8, 9 is connected to each other, and this connection point becomes an input terminal of the valve drive actuator drive timing adjustment circuit 52, and the electronic control unit ( It is connected to the second output port (denoted as "P ₂ " in FIG. 1) of the microcomputer 1 of 102. As shown in FIG.

An anode of the first regulating circuit diode 10 is connected to the other end of the first semi-fixed resistor 8, while an anode of the second regulating circuit diode 11 is connected to the other end of the second semi-fixed resistor 9. The cathode is connected. The cathode of the first regulating circuit diode 10 and the anode of the second regulating circuit diode 11 are connected to each other, and this connection point is connected to the input terminal of the inverter 12 and one end of the capacitor 13. It is.

In addition, the output terminal of the inverter 12 is connected to the gate of the previous second MOS-FET 3 together with the cathode of the second protective diode 5, and the other end of the capacitor 13 is connected to the second MOS-FET 3. It is connected to the ground terminal of the microcomputer 1 of the electronic control part 102 with the source of ().

Next, the operation in the above configuration will be described with reference to FIGS. 1 and 2. First, in the microcomputer 1, the timing of the target (in other words, the target timing of energization to the solenoid 14, that is, the target driving timing) to perform fuel injection by executing a program for fuel injection control, the fuel injection (In other words, the energization time to the solenoid 14) is calculated based on various input data, stored data, etc., and based on the calculation result, the target driving timing of the solenoid 14 (time t _s in FIG. The drive control signal Vst (refer to FIG. 2 (a)) is output from the second output port P ₂ at a timing earlier than a predetermined time T _{o from the} viewpoint.

In addition, micro-from the first output port P ₁ of the computer 1, the second output while the output control signal from the port P _2, the so-called repetition pulse repetition period is set according to the magnitude of the energizing current to the solenoid 14 is The first MOS-FET 2 is thus put into a so-called switching operation state.

This drive control signal Vst is applied to the valve drive actuator drive timing adjustment circuit 52, but when the logic level is High, the first semi-fixed resistor 8 and the first control circuit diode 10 Is applied to the input terminal of the inverter 12 while the logic level is low, the input terminal of the inverter 12 is logic via the second semi-fixed resistor 9 and the second regulating circuit diode 11. The value will be in the low state.

Then, when the drive control signal Vst of the rectangular wave as shown in Fig. 2 (a) is applied to the valve drive actuator drive timing adjustment circuit 52, the input terminal of the inverter 12 shows that shown in Fig. 2 (b). As described above, when the drive control signal Vst rises from the logic value Low to the high, the drive control signal Vst falls from the logic value High to the low, the drive control signal Vst becomes the logic value Low on the contrary in the section of the logic value High, and the drive control signal Vst Decreases from logic high to low, the signal waveform rises from logic low to high.

Corresponding to this, a signal obtained by inverting the signal VI of the input terminal is obtained at the output terminal of the inverter 12 (see Fig. 2 (c)). Here, the state of the output signal of the inverter 12 shown in FIG. 2 (c) is such that the values of the first and second semi-fixed resistors 8 and 9 are almost zero (unregulated state). The rise of the signal at the output terminal of the inverter 12 is almost delayed by a predetermined time T _{o at the} time when the logic value Low of the drive control signal Vst at the second output port P ₂ of the microcomputer 1 rises to High. . That is, first, the output timing of the drive control signal Vst output from the microcomputer 1 is said to be faster by a predetermined time T _o than the target drive timing, but this indicates that the drive control signal is applied to the gate of the second MOS-FET 3. The delay of the signal which occurs until it is applied is predetermined, and the driving control signal Vst is output earlier than the target driving timing in advance. As a result, the second MOS-FET 3 is in the conduction state almost at the target driving timing. It becomes to become.

In the injector 101 according to the embodiment of the present invention, when the solenoid 14 is in the energized state, the solenoid valve is opened to be injected, and the solenoid valve is closed by the energization stop to the solenoid 14 to the injection stop state. It shall be.

In the embodiment of the present invention, the drive control signal Vst is applied to the second MOS-FET 3 and its timing as described below by the adjustment of the first and second semi-fixed resistors 8 and 9. The pulse width is to be adjusted.

That is, first, the drive control signal Vst applied to the gate of the second MOS-FET 3 via the valve drive actuator drive timing adjustment circuit 52 is appropriately adjusted by adjusting the value of the first semi-fixed resistor 8. The rising timing of the high value at the logic value Low at the gate of the second MOS-FET 3 is delayed by an arbitrary time from the target driving timing ts to be applied to the gate of the second MOS-FET 3 (Fig. 2 ( d)). In addition, in FIG.2 (d), "T1" is based on the rise of the drive control signal (refer FIG. 2 (c)), when there is no delay of the drive control signal by the 1st semi-fixed resistor 8, The delay time of the drive control signal by the 1st semi-fixed resistor 8 from this reference point is shown.

Further, by appropriately adjusting the second semi-fixed resistor 9, at the logic value High of the drive control signal Vst applied to the gate of the second MOS-FET 3 via the valve drive actuator drive timing adjustment circuit 52. The time constant for falling to Low changes. In other words, it is possible to delay the OFF timing of the drive control signal applied to the gate of the second MOS-FET 3 at any time (see Fig. 2 (e)). In addition, in FIG.2 (e), "T2" is based on the fall of the drive control signal (refer FIG. 2 (c)), when there is no delay of the drive control signal by the 2nd semi-fixed resistor 9, The delay time of the fall of the drive control signal by the 2nd semi-fixed resistor 9 from this reference point is shown.

The drive control signal Vst output from the second output port P ₂ of the microcomputer 1 is applied to the gate of the second MOS-FET 3 via the valve drive actuator drive timing adjustment circuit 52, By appropriate adjustment of the one semi-fixed resistor 8, the timing of the rise from the logic value Low to High is delayed from the target driving timing (see FIGS. 2 (c) and 2 (d)), while the second semi-fixed resistor ( By the appropriate adjustment of 9), the falling timing of the logic value High to Low is delayed (see Figs. 2 (c) and 2 (e)).

Then, the second MOS-FET 3 is brought into a conducting state by turning its gate from logic low to high, while a so-called repeat pulse signal is output from the first output port P ₁ while the drive control signal is being output. As a result, the on / off of the first MOS-FET 2 is repeated, and the energization of the solenoid 14 is performed, and the amount of energization corresponds to the on / off cycle of the first MOS-FET 2. .

In the above-described configuration example, the energization of the solenoid 14 is performed via the first and second MOS-FETs 2 and 3, but the configuration may be such that the energization is performed via only one of them.

It goes without saying that a switch element other than the MOS-FET may be used.

In addition, the valve drive actuator drive timing adjustment circuit 52 allows the time constants of the condenser 13 and the first and second semi-fixed resistors 8 and 9 to be changed so that the delay times T1 and T2 can be adjusted. However, of course, it does not need to be limited to such a structure.

For example, it is a matter of course that the actuator driving timing adjustment circuit 52 for valve driving may be configured by using a known and known so-called timer IC that outputs a pulse having a predetermined pulse width at a predetermined timing by an external trigger signal. . Such a timer IC is comprised so that the output timing of the output pulse signal and its pulse width can be adjusted by the variable resistor provided in an external terminal, for example.

Instead of the solenoid valve serving as the valve driving actuator, for example, an actuator made of a piezoelectric element is used, the valve driving actuator driving timing adjusting circuit according to the present invention is provided to the driving circuit to adjust the driving timing. Of course, you may apply.

In addition, the fuel injection device in the embodiment of the present invention does not need to be limited to a specific type, and is of course related to a new type such as a so-called common rail type injection device that has been developed and put into practical use in addition to the conventional configuration. none.

As described above, according to the present invention, since the drive timing of the valve drive actuator of the injector can be adjusted, it is related to the deviation of the electrical characteristics of the valve drive actuator itself, the deviation of the electronic components constituting the drive circuit, and the like. The actuator can be driven at a desired timing at any time, and can be applied regardless of the need for high-speed response. Therefore, the versatility is high, and the effect of ensuring the proper injector operation can be ensured. have.

Claims (6)

It is provided at the input end of the drive circuit configured to conduct electricity to the valve drive actuator via the switch element brought into a conductive state by the application of the drive control signal, And adjusting the rise and fall timing of the drive control signal applied to the switch element. Actuator drive timing adjustment circuit for valve drive. It is provided at the input end of the drive circuit configured to conduct electricity to the valve drive actuator via the switch element brought into a conductive state by the application of the drive control signal, First and second semi-fixed resistors, one end of which is connected to each other to apply a drive control signal; A first regulating circuit diode having an anode connected to the other end of the first semi-fixed resistor; A second regulating circuit diode having a cathode connected to the other end of the second semi-fixed resistor; The cathode of the first regulating circuit diode and the anode of the second regulating circuit diode are connected to an input terminal and the input terminal has an inverter connected to ground via a capacitor, and the output signal of the inverter is Characterized in that configured to be applied to the switch element Actuator drive timing adjustment circuit for valve drive. An injector configured to open and close a valve by injecting a valve driving actuator to inject fuel, The injector is a valve drive actuator driving timing adjustment circuit according to claim 1 is housed, characterized in that the injector. An injector configured to open and close a valve by injecting a valve driving actuator to inject fuel, The injector is a valve drive actuator drive timing adjustment circuit according to claim 2 is housed, characterized in that the injector. A fuel injector having an injector configured to be able to inject fuel by opening and closing a valve by driving a valve driving actuator, The injector is a fuel injection device, characterized in that the valve drive actuator drive timing adjustment circuit according to claim 1 is accommodated. A fuel injector having an injector configured to be able to inject fuel by opening and closing a valve by driving a valve driving actuator, The injector is a fuel injection device, characterized in that the valve drive actuator drive timing adjustment circuit according to claim 2 is accommodated.