JPS60157969A - Steering-force controller for power steering apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a steering force control device for a power steering device used in an automobile, etc., and in particular, to a steering force control device for a power steering device used in an automobile, etc. The present invention relates to a control device.

[Prior art]

As shown in FIG. 1, the above steering force control device includes a pump (
1) extracts the steering hydraulic pressure (PC) supplied to the power cylinder (3) via the power steering and control valve (2), and sends pulses corresponding to the vehicle speed signal from the vehicle speed sensor (8) to the electrical system. By controlling the proportional solenoid (6) via the control device (7), the hydraulic pressure control valve (5) is controlled, the hydraulic pressure (PC) is controlled, and this controlled hydraulic pressure (PR) is transferred to the control valve. (2
) into the reaction force chamber (4) provided in the steering wheel.
A steering force is generated at the wheels according to the steering load and vehicle speed.

However, in the process of manufacturing a vehicle equipped with the above-mentioned steering force control device or when maintaining it at a service shop in the market, it is necessary to check each vehicle to confirm that the steering force increases as the vehicle speed increases. It is often difficult to run.

In addition, checking the steering force at high speed using a special and difficult-to-handle measuring device such as an oscillator, especially at a service shop in the market, has the disadvantage of increasing the burden on the maintenance engineer.

[Summary of the invention]

The present invention solves the above-mentioned drawbacks and provides an electrical system control device that can check the state of the check terminal.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 2 and 8. In Figure 2, (6) is a proportional solenoid, (8)
is a vehicle speed sensor, (9) is a key switch, αQ is an on-board battery, α is a switch or connector connected to a check terminal, and (6) is a high-speed state check resistor. (
7) is a vehicle speed sensor (8) using battery α() as a power source.
This is an electrical control device that receives a signal from the vehicle and outputs a current that is inversely proportional to the vehicle speed to drive the proportional solenoid (6).It has the following internal configuration. (701'1 is a pulse frequency corresponding to the vehicle speed of the vehicle speed sensor (8) (Fig. 8 (a))
(702) is an NPN type transistor (70g ) is a charging resistor, (704) is a discharging resistor, (718) is a charging/discharging resistor, (705) is a resistor (708), (70
4) and (718) form a charging/discharging circuit, and a voltage inversely proportional to the pulse frequency of the vehicle speed sensor (8) (Fig. 8 (C)
) is output to point C in FIG. 2. (706) is an error amplification circuit that operates using the voltage across the capacitor (705), that is, the φ-converted voltage of the vehicle speed, as a reference voltage.

(707) is the output waveform to the solenoid (6) in pWM
( ) (111 width modulation) Fundamental frequency (50
0~t,oo.

This is a triangular wave (or sawtooth wave) oscillation circuit.

(708) is a PWM circuit that compares the output voltage of the error amplification circuit (706) with the output voltage of the triangular wave oscillation circuit (707) and amplifies the error. (709) is the proportional solenoid (6)
A proportional solenoid drive circuit that allows drive current to flow through (
A shaft resistor (710) is inserted in series between the proportional solenoid (6) and ground to detect the drive current.
1) is m1 generated at both ends of the shaft resistance (710).
A solenoid current detection circuit that detects and amplifies the voltage drop and returns a voltage corresponding to the energized current of the solenoid (6) to the error amplification circuit (706). A stabilized power supply (6 to 8
This is a constant voltage circuit that supplies V).

The operation of the device U of the present invention configured as above will be explained. First, turn on the key switch (9) when the vehicle is stopped (switch (B) is off). In other words, when the vehicle is idling, power is directly supplied from the battery αQ to the proportional solenoid drive circuit (709) via the key switch (9). The other circuits are supplied with constant voltage power through a constant voltage circuit (712).

Therefore, a stabilized voltage is also applied to resistors (708) (71B) (704), so point C is connected to resistor (708).
(718) Proportional solenoid (6) has maximum current (approximately IA
)...The output voltage of the solenoid current detection circuit (711) is balanced at the point where the voltage matches the reference voltage, that is, the point where the current flowing through the solenoid (6) is about IA. Therefore, The hydraulic reaction force becomes minimum and the steering force becomes small. Next, when the car starts running and the vehicle speed sensor (8) starts outputting a vehicle speed pulse, a vehicle speed pulse having a waveform as shown in FIG. 8(a) is applied to point a. Upon receiving this signal, one-shot
The multivibrator (701) outputs a constant width pulse having a waveform as shown in FIG. 8(b) at point b.

For each pulse of the slave-7 lever, the transistor (702)
The capacitor (705) is conductive for a certain period of time, and the charge stored in the capacitor (705) is discharged through the resistor (718) and the transistor (702), and the average potential across the capacitor (705) decreases. In other words, since the reference voltage of the error amplification circuit (706) decreases, the flow of the solenoid (6) reaches a level at a point where the flow also decreases, and the hydraulic reaction force increases in accordance with the vehicle speed, making the steering wheel operation heavy. It is now possible to obtain stable mE force.

Therefore, a steering force test is conducted under high-speed running conditions on a vehicle equipped with a power steering system that exhibits characteristics such that the steering reaction force gradually increases with respect to the vehicle speed as detailed above. In this case, when the car is stopped and the switch Oυ is turned on and the variable resistor 04 is decreased, the vehicle speed characteristics at the six points are as shown by the broken line B in Fig. 8(C) when the switch aη is turned off. The solenoid current decreases compared to +11 A, and a reference voltage equivalent to that in the high-speed state is output to the error amplifier circuit (706), the current flowing through the proportional solenoid (6) decreases, and the hydraulic reaction force increases. , it is possible to realize a heavy steering force state corresponding to a high-speed driving state.

In this embodiment, a variable resistor is connected to the check terminal via the switch αη so that the high-speed state can be changed as appropriate. However, a connector is attached in place of the switch Ql), and the variable resistor (2) is By incorporating a fixed resistor corresponding to the high-speed state instead of attaching it to the high-speed state and grounding one end of the connector, it is possible to realize the high-speed state at one point with a simpler configuration.

Furthermore, although the discharge switching element is configured with a transistor (702), the same effect can be obtained by using a comparator instead.

〔Effect of the invention〕

As described above, according to the present invention, the simple structure has advantages.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a steering force control device to which this invention is applied, FIG. 2 is a block diagram of an electrical system control device of the steering force control device of this invention, and FIG. 8 is a block diagram of each part of the device according to this invention. FIG. 3 is a characteristic diagram showing characteristics. In the figure, (6) is a proportional solenoid, (7) is an electric control device, (8) is a vehicle speed sensor, (9) is a key switch, α1 is a battery, 0υ is a switch, Qa is a variable resistor, (70
1) is a multi-vibrator, (702)
is a transistor, (708) (704) (718)
is a resistor, (705) is a capacitor, (706) is an error amplifier circuit, (707) is a triangular wave oscillation circuit, (708) is a P
WM circuit, (709) is proportional solenoid drive circuit, (7
1G) is a resistor, (711) is a solenoid current detection circuit, and (712) is a constant voltage circuit. Agent Masuo Oiwa Figure 1 Figure 3 1 hour 1 hour 1 storage

Claims (2)

[Claims] (1) A power steering system that applies a control signal according to the vehicle speed to a proportional solenoid and adjusts the W1 current flowing through the coil of the proportional solenoid to control the hydraulic control valve and obtain an appropriate steering reaction force hydraulic pressure. In the control device, an F/V conversion circuit inputs a vehicle speed signal from a vehicle speed sensor and outputs an output voltage inversely proportional to the vehicle speed, and compares the output of this FA conversion circuit with a feedback voltage corresponding to the current flowing through the proportional solenoid. An error amplification circuit that amplifies the difference, a proportional solenoid drive circuit that controls the proportional solenoid based on the output of this error amplification circuit, a terminal that draws the output of the F/V conversion circuit to the outside, and a terminal that is connected between this terminal and ground. A high-speed running state setting resistor and a switch means are provided, and by connecting the resistor with the switch means, the output voltage of the F/V conversion circuit is lowered and the high-speed running state is set even though there is no vehicle speed signal from the vehicle speed sensor. A steering force control device for a power steering system that allows similar steering reaction forces to be obtained. (2) A steering force control device for a power steering device according to claim 1, wherein the resistance is a variable resistance so that the high speed state can be varied in various ways.