JPH06211153A - Actuator control device of vehicle - Google Patents

Abstract

PURPOSE:To provide an actuator control device for a vehicle which can find the control amount of an actuator at a low cost, accurately, and rapidly. CONSTITUTION:A car speed sensor 1 outputs a car speed pulse with the pulse width corresponding to the car speed, and an edge detecting circuit 3 detects the edge of the car speed and outputs an edge signal. A counter 5 counts a clock signal transmitted between neighboring edge signals. A decoder 11 selects a car speed value data corresponding to the counter value, and furthermore, selects a current value data corresponding to the car speed value data, so as to input the result to a ratch circuit 7. The ratch circuit 7 ratches the current value data in the edge signal output time, and outputs it to a power steering driver. Since the current value data is found by the input and the output of the digital data, the result is more accurate and rapid than the case of converting from frequency to voltage. The cost is lower than the case of using a microcomputer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle actuator control device for controlling various vehicle actuators according to the vehicle speed.

[0002]

2. Description of the Related Art In recent years, various actuators have been mounted on vehicles with the progress of electronic technology. For example, as for the steering device, a power steering device is mounted that assists the driver's steering wheel operation by using hydraulic pressure. In this type of power steering device, the control valve is opened and closed according to the vehicle speed to control the assisting force. In a conventional vehicle, this vehicle speed is variously detected by arranging an electromagnetic pickup sensor near the rotor that rotates with the wheels and detecting it from the pulse width of a pulse signal (hereinafter referred to as a vehicle speed pulse) generated by the electromagnetic pickup sensor. Is used to control the.

Conventionally, when the actuator control amount is determined based on the pulse width of the vehicle speed pulse as described above, the vehicle speed pulse is subjected to frequency-voltage conversion, and the voltage signal is further subjected to various conversions to obtain the actuator control amount. Is being done.

[0004]

However, the frequency-voltage conversion usually requires a large number of parts such as a one-shot circuit, which complicates the configuration of the control device. Further, in the frequency-voltage conversion, the required actuator control amount also varies due to variations in the performance of the components used. Furthermore, a response delay occurs when performing frequency-voltage conversion.

On the other hand, it has been considered to input a pulsed input signal to a microcomputer and obtain the actuator control amount by software. However, in this case, since the CPU or the like is used, the control device becomes expensive. Therefore, the present invention has been made for the purpose of providing an actuator control device for a vehicle that is inexpensive and can accurately and promptly determine the control amount of the actuator.

[0006]

SUMMARY OF THE INVENTION The present invention, which has been made to achieve the above object, provides a vehicle speed pulse generating means for generating a vehicle speed pulse whose pulse width changes according to the vehicle speed, and a clock signal at a predetermined interval. Clock, a counter that counts the clock signal generated between the edges of the vehicle speed pulse, and a decoder that converts the count value of the counter into digital data corresponding to the actuator control amount. The main point is the vehicle actuator control device.

[0007]

In the present invention thus constructed, the counter counts the clock signal generated between the edges of the vehicle speed pulse, and the decoder converts the counted value into digital data corresponding to the actuator control amount.

Here, the clock, the counter, and the input / output signals of the decoder which constitute the present invention are all digital data. Therefore, there is no variation in the obtained actuator control amount due to variations in component performance. Further, no response delay occurs in the conversion of digital data.

Further, according to the present invention, the clock signals generated between the edges of the vehicle speed pulse are counted and converted into digital data corresponding to the actuator control amount as data corresponding to the vehicle speed. Therefore, the following advantages occur as compared with the case where vehicle speed pulses generated in a certain period are counted to obtain data corresponding to the vehicle speed. That is, according to the present invention, digital data corresponding to each vehicle speed pulse width can be obtained. Therefore, even when the vehicle speed fluctuates greatly and the vehicle speed pulse width fluctuates greatly, it is possible to accurately and promptly respond to the vehicle speed fluctuation.

Furthermore, according to the present invention, since the vehicle speed pulse is converted into the actuator control amount by the clock, the counter, and the decoder, the manufacturing cost can be reduced as compared with the case of using the microcomputer.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a block diagram showing a power steering system of an embodiment to which a vehicle actuator control system of the invention is applied.

First, in a vehicle equipped with the actuator control apparatus of this embodiment, a known electromagnetic pickup type vehicle speed sensor 1 is provided in the vicinity of a rotor (not shown) that rotates together with wheels.
Is provided and outputs a vehicle speed pulse whose pulse width becomes shorter as the vehicle speed increases. That is, the vehicle speed sensor 1 corresponds to vehicle speed pulse generation means.

The vehicle speed pulse output from the vehicle speed sensor 1 is input to the edge detection circuit 3. The edge detection circuit 3 detects the rising edge of the input vehicle speed pulse and outputs a short pulse-shaped edge signal. The edge signal of the edge detection circuit 3 is input to the counter 5 as a reset signal and also to the latch circuit 7 as a clock signal. The latch circuit 7 is a well-known circuit that holds (latches) the signal input from the input terminal when the clock signal is input.

The counter 5 receives a clock signal transmitted by the clock 9 at a predetermined interval, and inputs a value obtained by counting the clock signal (hereinafter referred to as a counter value) to the decoder 11. The counter 5 is reset at the falling edge of the reset signal (edge signal) from the edge detection circuit 3.

The decoder 11 comprises a vehicle speed value ROM 11a for storing a large number of vehicle speed value data and a current value ROM 11b for storing a large number of current value data. Each ROM1
The vehicle speed value data and the current value data stored in 1a and 11b are in one-to-one correspondence with each other as shown in FIG.
Then, when the counter value is input from the counter 5, the decoder 11 selects the vehicle speed value data corresponding to the counter value, further selects the current value data corresponding to the vehicle speed value data, and causes the latch circuit 7 to select the current value data. input.

Returning to FIG. 1, the latch circuit 7 latches the current value data output from the decoder 11 when the clock signal (edge signal) input from the edge detection circuit 3 falls. Then, this current value data is D /
Output to the power steering drive unit 20 via the A converter 13. As will be described later, the power steering drive unit 20 controls the current supplied to the solenoid 21 based on the current value data, and adjusts the opening degree of a control valve (not shown) of the power steering device.

Next, based on the time chart of FIG. 3, changes in signals input and output between the above circuits will be described. As shown in the figure, the vehicle speeds are akm / h, bkm / h, ckm / h, dkm / h,
... changes accordingly, the pulse width of the vehicle speed pulse,
As a result, the interval between adjacent edge signals changes. The counter 5 is reset at the falling edge of the edge signal. Therefore, the counter value of the counter 5 becomes 0 at the falling edge of the edge signal and continues to increase until the next falling edge signal. Further, at this time, the vehicle speed value data selected from the vehicle speed value ROM 11a also changes with the change in the counter value. As described above, the pulse width of the vehicle speed pulse becomes shorter as the vehicle speed increases. Therefore,
As the counter value increases, the corresponding vehicle speed value data decreases.

The current value data of the current value ROM 11b has a one-to-one correspondence with the vehicle speed value data of the vehicle speed value ROM 11a. Therefore, the current value data input to the latch circuit 7 also changes in accordance with the change in the vehicle speed value data. Here, as illustrated in FIG. 2, the correspondence relationship of each data is set such that the corresponding current value data decreases as the vehicle speed value data increases. Therefore, the current value data input to the latch circuit 7 increases as the vehicle speed value data decreases. When the edge signal falls, the latch circuit 7 receives the current value data (I
a, Ib, Ic, ...) are latched. Then, the current value data is output to the D / A converter 13 as a target current value until the edge signal falls next time. The D / A converter 13 outputs to the power steering drive unit 20 a voltage Vi having a correspondence relationship to be described later with the input target current value.

Next, returning to FIG. 1, the configuration of the power steering drive unit 20 and the operation of the power steering drive unit 20 when the voltage Vi is input will be described.
One end of the solenoid 21 is connected to the DC power supply 25 via the collector / emitter of the transistor 23. The other end of the solenoid 21 is connected to the ground electrode 29 via the resistor 27. Therefore, a voltage VR having a magnitude proportional to the current flowing through the solenoid 21 is applied across the resistor 27. The voltage VR is amplified by the amplifier 31 to become the voltage VF, which is input to the differential amplifier 33 together with the output voltage Vi of the D / A converter 13.

The output terminal of the differential amplifier 33 is connected to the base of the transistor 23 via the duty converter 35 and the amplifier 37. Therefore, the differential amplifier 33
The voltage Vi corresponding to the target current value is compared with the voltage VF corresponding to the energization current of the solenoid 21, and the difference (Vi-
The voltage Vo proportional to VF) is output to the duty converter 35. The duty converter 35 converts the voltage Vo into an ON / OFF signal having a duty ratio according to its magnitude, and inputs the ON / OFF signal to the base of the transistor 23 via the amplifier 37.

With the above configuration, in the power steering drive unit 20, the solenoid 21 is set so that VF = Vi.
It is possible to control the energizing current to. Where voltage V
i is set so that the energizing current of the solenoid 21 and the target current value match when VF = Vi. Therefore, the energizing current of the solenoid 21 can be controlled to the target current value by the D / A converter 13 and the power steering drive unit 20.

The collector of the transistor 23 is connected to the ground electrode 29 via the diode 39. When the transistor 23 is turned off, a negative surge voltage is generated in the collector, but this surge voltage can be absorbed by the current flowing from the ground electrode 29 through the diode 39.

With the above-described structure, in the power steering system of this embodiment, the current supplied to the solenoid 21 can be controlled according to the vehicle speed, and the opening of the control valve can be adjusted. Further, in the power steering apparatus of the present embodiment, the current value data is obtained by inputting / outputting digital data by the edge detection circuit 3 to the decoder 11.
Therefore, there is no variation in the obtained current value data due to the variation in the performance of each of the circuits 3 to 11 constituting the present embodiment. Furthermore, no response delay occurs in the conversion of the digital data.

Further, in this embodiment, the clock signal generated between the edges of the vehicle speed pulse is counted, and the current value data is obtained by using this as the data corresponding to the vehicle speed. Therefore, compared to the case where the number of vehicle speed pulses for a certain period is counted, it is possible to accurately respond to the vehicle speed fluctuation even when the vehicle speed fluctuates significantly.

Therefore, in this embodiment, the current value data, that is, the control amount of the power steering device can be accurately and promptly obtained. On the other hand, it is also possible to input the vehicle speed pulse of the vehicle speed sensor 1 into a microcomputer and perform the same calculation as in the present embodiment by software.
In this case, the device becomes expensive. On the other hand, in the present embodiment, the vehicle speed pulse is converted into the current value data by the edge detection circuit 3, the counter 5, the clock 9, and the decoder 11, so that it is manufactured at a lower cost than when a microcomputer is used. can do.

Although the control amount of the power steering device is obtained in the above embodiment, the vehicle actuator control device of the present invention is an antiskid device, a constant speed traveling device, or any other device for controlling the actuator according to the vehicle speed. The control amount can be obtained by applying the control amount to the above device. Further, in the above embodiment, the vehicle speed value data is selected by the counter value counted between the rising edges of the vehicle speed pulse, but the counter value between the falling edges may be used, and the rising and falling edges may be used. You may use the counter value between the included edges. In the latter case, the change in vehicle speed can be grasped more finely.

[0027]

As described in detail above, in the vehicle actuator control device of the present invention, the actuator control amount is obtained by the input / output of digital data by the clock, the counter, and the decoder. Therefore, there is no variation in the required actuator control amount due to the variation in the performance of the components constituting the present invention. Also,
No response delay occurs in the conversion of digital data.

Further, in the present invention, the clock signals generated between the edges of the vehicle speed pulse are counted, and this is converted into digital data corresponding to the actuator control amount as data corresponding to the vehicle speed. Therefore, even when the vehicle speed fluctuates significantly, it is possible to accurately and promptly respond to the vehicle speed fluctuation.

Therefore, according to the present invention, the actuator control amount can be obtained accurately and quickly. Further, according to the present invention, since the vehicle speed pulse is converted into the actuator control amount by the clock, the counter, and the decoder,
It can be manufactured at a lower cost than when a microcomputer is used.

[Brief description of drawings]

FIG. 1 is a block diagram showing a power steering device of an embodiment.

FIG. 2 is a block diagram showing an internal configuration of a decoder of the power steering device.

FIG. 3 is a time chart showing changes in input / output signals of the power steering device.

[Explanation of symbols]

1 ... Vehicle speed sensor 3 ... Edge detection circuit
5 ... Counter 7 ... Latch circuit 9 ... Clock
11 ... Decoder 13 ... D / A converter 20 ... Power steering drive unit 21 ... Solenoid

Claims (1)

[Claims] 1. A vehicle speed pulse generating means for generating a vehicle speed pulse whose pulse width changes according to a vehicle speed, a clock for generating a clock signal at a predetermined interval, and the clock signal generated between the edges of the vehicle speed pulse. An actuator control device for a vehicle, comprising: a counter that counts; and a decoder that converts a count value of the counter into digital data corresponding to an actuator control amount.