JP2709409B2 - Power steering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is used for a power steering device of an automobile. The present invention relates to an improvement in a connection point between a hydraulic assist booster for steering a front wheel and a vehicle frame.

〔Overview〕

The present invention relates to a power steering device that turns a vehicle with a light steering force by adding hydraulic power, and by connecting one end of a hydraulic assist booster that steers front wheels and a frame via an elastic material, This eliminates the sense of incongruity due to the steering force applied by the hydraulic pressure received by the steering wheel.

[Conventional technology]

Applicant has applied for a power steering device comprising a hydraulic auxiliary booster that is separately installed in the steering device.
63-251470.

The configuration and operation of the power steering device using the hydraulic assist booster will be described with reference to FIGS. 1, 2 and 3.

The device includes a steering device 2 that is mechanically connected to the steering wheel 1, a steering force sensor 3 that electrically detects a steering force of the steering wheel 1,
A hydraulic pressure generating means 4 including a pump 4a and a reservoir 4b for generating hydraulic pressure, a hydraulic auxiliary booster 5 connected to the steering device 2 and having one end directly connected to the frame 53 by a ball joint, and a pressure generated by the hydraulic pressure generating means 4. There are provided electromagnetic valves 6a and 6b for introducing oil into the hydraulic auxiliary booster 5, and a program control circuit 7 for taking in the output of the steering force sensor 3 and controlling the electromagnetic valves 6a and 6b. A reaction force hydraulic means 21 for providing a reaction force is included. The reaction force hydraulic means 21 includes left and right correction valves 22a and 22b for introducing pressure oil to be applied to the hydraulic auxiliary booster 5.

In the conventional device configured as described above, when the steering force sensor 3 detects the start of steering and the return of steering, the program control circuit 7 receives the detection output and controls the solenoid valves 6a and 6b to perform left correction. By operating the valve 22a or the right correction valve 22b to supply the hydraulic oil to the hydraulic auxiliary booster 5 to apply the steering force, the hydraulic oil is supplied to the reaction force hydraulic means 21 to apply the reaction force. Further, according to the control of the program control circuit 7,
The reaction force applied to the steering wheel 1 is controlled according to the change in the vehicle speed output from the speed sensor.

[Problems to be solved by the invention]

In the conventional power steering device described above, since one end of the hydraulic assist booster and the frame are directly connected by the ball joint, the pressure generated in the hydraulic assist booster when steering is changed rapidly, and at the same time, the pressure is reduced by the reaction force. There is also a problem that the steering force is transmitted to the steering wheel in a pulsating manner because it is also generated in the hydraulic means, giving the driver an uncomfortable feeling.

An object of the present invention is to solve such a problem, and an object of the present invention is to provide a device that can eliminate a sense of discomfort experienced when operating a steering wheel.

[Means for solving the problem]

The present invention relates to a steering device connected to a steering wheel by a mechanical system, a steering force sensor for electrically detecting a steering force of the steering wheel, a hydraulic pressure generating means, and one end connected to the steering device, and one end of a frame of an automobile. A hydraulic auxiliary booster coupled to the hydraulic pressure booster, a solenoid valve that introduces pressure oil generated by the hydraulic pressure generating means into the hydraulic auxiliary booster, and a program control circuit that receives an output of the steering force sensor and controls the electromagnetic valve. The steering apparatus further includes a reaction force hydraulic unit that applies a reaction force to the steering wheel, and a correction valve that introduces pressure oil to the hydraulic assist booster to the reaction force hydraulic unit. A connecting means made of an elastic material is provided at a connecting point between the auxiliary booster and the frame of the vehicle. To.

[Action]

The elastic material interposed at the connection point between the hydraulic assist booster and the steering device absorbs the pressure pulsation generated in the hydraulic assist booster and eliminates the feeling of discomfort to the steering wheel.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings. First
FIG. 2 is a diagram showing the general configuration of a conventional example and an embodiment of the present invention. FIG. 2 is a diagram showing the general configuration of a conventional example and a hydraulic system including a hydraulic system in a neutral position of a steering wheel, and FIG. FIG. 4 is a cross-sectional view illustrating a joint between a hydraulic assist booster and a frame according to an embodiment of the present invention.

The embodiment of the present invention includes a steering device 2 connected to a steering wheel 1 by a mechanical system, and a steering force sensor 3 for electrically detecting a steering force of the steering wheel 1.
And a hydraulic pressure generating means 4 including a pump 4a and a reservoir 4b
A hydraulic auxiliary booster 5 connected to the steering device 2, electromagnetic valves 6a and 6b for introducing the hydraulic oil generated by the hydraulic pressure generating means 4 to the hydraulic auxiliary booster 5, and an electromagnetic valve 6a which takes in the output of the steering force sensor 3 Control circuit 7 for controlling, 6b
And a speed sensor 8. The steering device 2 includes a reaction force hydraulic means 21 for applying a reaction force to the steering wheel 1.
The reaction force hydraulic means 21 includes a left correction valve 22a and a right correction valve 22b for introducing pressure oil to be applied to the hydraulic auxiliary booster 5. Further, as a feature of the present invention, as shown in FIG. At the connection point between the booster 5 and the frame 53, a coupling means 51 made of an elastic material is provided. As the coupling means 51, for example, a bush made of synthetic rubber is used.

Next, the operation of the embodiment of the present invention thus configured will be described.

First, when the steering wheel 1 is in the neutral position, the pressure oil from the pump 4a passes through the reaction force hydraulic means 21 and returns to the reservoir 4b as shown in FIG. Will be maintained.

At the same time, the pressure oil supplied to the left correction valve 22a and the right correction valve 22b is held by the solenoid valves 6a and 6b, respectively.

Here, as shown in FIG.
Is turned to the left, the start of steering is detected by the steering force sensor 3, and a detection signal is sent to the program control circuit 7. Upon receiving this detection signal, the program control circuit 7 controls the solenoid valve 6a to operate the left correction valve 22a to move it in the direction of the arrow A.

Due to this movement, the pressure oil supplied from the pump 4a passes through the left correction valve 22a, and one of them is sent to the hydraulic chamber a of the hydraulic auxiliary booster 5, and moves the piston 210 in the direction of arrow B to move the front wheel 9
To steer. The other pressure oil that has passed through the left correction valve 22a is directly supplied to one side (the upper part in FIG. 4) of the piston 210 of the reaction force hydraulic means 21, and also passes through the valve 11 and the right correction valve 22b, and Is also supplied to the other side (lower in FIG. 4) of the piston 210, and a reaction force is applied to the steering wheel 1 by the pressure difference between the pressure oils on both sides of the piston 210.

The valve 11 is opened and closed by a stepping motor 10 controlled by the program control circuit 7, and the program control circuit 7
Performs the control corresponding to the vehicle speed based on the detection output from the speed sensor 8, controls the stepping motor 10 so that the steering force becomes heavy with the increase in the vehicle speed, and changes the hydraulic pressure of the reaction force hydraulic means 21.

Here, the feature of the present invention is that, as shown in FIG.
53 and 53 by means of a pin 54 with connecting means 51 interposed.

If the steering wheel 1 is turned to the left, the steering force sensor 3 sends a detection signal to the program control circuit 7, and the program control circuit 7 controls the solenoid valve 6a based on the detection signal to operate the left correction valve 22a. Make it work.

By the operation of the left correction valve 22a, the pressure oil sent from the pump 4a is supplied to the pressure chamber a of the hydraulic auxiliary booster 5. The pressure oil supplied at a pressure necessary to steer the front wheel 9 moves the piston 210 in the direction of the arrow B shown in FIG. 3, and provides an assisting force to the steering device 2 via the mechanical linkage. At the same time, the pressure oil that has passed through the left correction valve 22a is also guided to the reaction force hydraulic means 21 at the same pressure as the pressure supplied to the pressure chamber a of the hydraulic auxiliary booster 5, and applies a reaction force to the steering wheel 1.

During the transmission of the auxiliary force, the force from the hydraulic auxiliary booster 5 is transmitted to the coupling means 51 for a moment, and the coupling means 51 absorbs the pulsation of the pressure generated in the hydraulic auxiliary booster 5 and is supplied to the reaction force hydraulic means 21. Also absorbs the pulsation of pressure oil.

〔The invention's effect〕

As described above, according to the present invention, there is an effect that the pulsation of the steering force given from the hydraulic assist booster is absorbed, and the sense of discomfort experienced when operating the steering wheel can be eliminated.

[Brief description of the drawings]

FIG. 1 is a diagram showing an entire configuration of a conventional example and an embodiment of the present invention. FIG. 2 is a diagram showing the entire configuration of a conventional example and a steering system including a hydraulic system in a neutral position of a steering wheel according to an embodiment of the present invention. FIG. 3 is a view for explaining left-turn left correction in the conventional example and the embodiment of the present invention. FIG. 4 is a cross-sectional view showing a joint between the hydraulic assist booster and the frame in the embodiment of the present invention. 1 ... steering wheel, 2 ... steering device, 3 ... steering force sensor, 4 ... hydraulic pressure generating means, 4a ...
Pump, 4b ... Reservoir, 5 ... Hydraulic auxiliary booster, 6
a, 6b: Solenoid valve, 7: Program control circuit, 8:
Speed sensor, 9 ... front wheel, 10 ... stepping motor,
11 ... valve, 21 ... reaction force hydraulic means, 22a ... left correction valve, 22b ... right correction valve, 51 ... coupling means, 52 ... rod end, 53 ... frame, 54 ... pin, 210 ……piston.

Claims (1)

(57) [Claims] 1. A steering device connected to a steering wheel by a mechanical system, a steering force sensor for electrically detecting a steering force of the steering wheel, a hydraulic pressure generating means, and one end of the vehicle connected to the steering device. A hydraulic auxiliary booster coupled to a frame, an electromagnetic valve that introduces pressure oil generated by the hydraulic pressure generating means to the hydraulic auxiliary booster, and a program control circuit that receives an output of the steering force sensor and controls the electromagnetic valve. The steering apparatus further includes: a reaction hydraulic pressure unit that applies a reaction force to the steering wheel; and a correction valve that introduces pressure oil to the hydraulic auxiliary booster to the reaction hydraulic pressure unit. A coupling means made of an elastic material is provided at a coupling point between the hydraulic auxiliary booster and the vehicle frame. Power steering device, characterized in that.