JPH1071958A - Power steering device for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce operation force of a steering wheel even if a thick control cable is used by detecting a turning angle of the steering wheel, and rotating a steering wheel side drum by a control motor in response to the detected turning angle of the steering wheel. SOLUTION: When a steering wheel 1 is rotated in one direction, a turning angle is detected by a detecting device 32, and a signal is amplified by an amplifier 33. It is inputted to a control motor 30, and an output shaft 31 of the control motor 30 is rotated by an angle corresponding to the steering wheel 1, and a steering wheel 1 side drum 7 is rotated by the same angle as the steering wheel 1, and a cable is wound round the drum 7. One of an inner cable of a control cable 4 is wound round the steering wheel 1 side drum 7, thereby tension is generated, the inner cable is delivered from the drum 7 on the steering position side, and the drum 7 and a rotary shaft are rotated in one direction. Therefore, tension of the inner cable can easily be adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power steering apparatus for an automobile using two control cables and a power cylinder acting on a pulling force, and more particularly, to improving steering characteristics and safety by using a thick control cable. Also, the present invention relates to a power steering device for an automobile that can reduce the operating force of a steering wheel.

[0002]

2. Description of the Related Art The applicant of the present application discloses a power cylinder having a piston rod connected to a front wheel via a steering link mechanism at both ends, and is supplied to the power cylinder and simultaneously discharged from the power cylinder. A rotary control valve for controlling the direction of pressurized oil, a valve-side drum connected to the rotor of the control valve, a handle-side drum connected to the handle, and a freely sliding inside the flexible outer tube. Patent application for a power steering apparatus for an automobile, wherein the inner cable inserted includes two control cables wound around both drums so that tensile force acts alternately when the handle side drum is rotated in an alternate direction. And
The application was published as JP-A-8-2431.

[0003]

The invention according to this patent application has the advantage that the steering force is transmitted using the control cable, so that the wiring can be freely bent in a narrow engine room. However, it is necessary to use a thick control cable in order to reduce the elongation to enhance the steering characteristics and increase the breaking strength, so that the sliding resistance of the inner cable to the outer tube increases, and the operating force of the steering wheel increases. There is a problem that becomes large.

[0004]

According to the present invention, as a means for solving the above-mentioned problems, in the above-mentioned invention, there is provided a detecting means for detecting a rotation angle of a steering wheel, and a detecting means for detecting a rotation angle of the steering wheel detected by the detecting means. And a control motor for rotating the handle-side drum.

[0005]

The present invention has the above-described structure, and the steering wheel merely indicates the steering angle, and the control motor substantially bears the operation force of the control cable. Therefore, even if a thick control cable is used, the operation force of the handle can be reduced. This has the effect of being significantly reduced.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a handle, which is rotatably supported by a case 2 attached to a vehicle body.

A case 2 having the same structure as the case 2 is disposed at a steering position in front of the vehicle body, and a terminal is fixed to the cases 2 and 2 between the two cases 2 and 2 by a cylindrical fixing member 3. Two flexible control cables 4 are routed.

The control cable 4 is a cable in which the inner cable 6 is slidably inserted into the outer tube 5. As shown in FIG. 3, the cylindrical fixture 3 is crimped to the end of the outer tube 5. A male screw 11 formed on the outer periphery is screwed into a female screw 12 formed in the case 2, and the length of the control cable 4 is adjusted by the rotation of the cylindrical fixture 3, and is fixed by the nut 13. The inner cable 6 is wound around a drum 7 rotatably supported in the case 2. The winding directions of the two inner cables 6 are opposite to each other, and their ends are fixed to the drum 7.

A rotating shaft 8 of the drum 7 protrudes from one surface of the case 2, and is connected to the rotating shaft of the handle 1 on the handle 1 side and a rotary valve 9 described later on the steering position side.
, Respectively.

Numeral 14 denotes a piston 1 in a cylinder tube 15.
6 is a power cylinder in which the piston 6 is slidably fitted, a rack 18 is formed by extending one side of a piston rod 17 fixed to the piston 16, and tie rods 20 are connected to both ends via ball joints 19. The tie rod 20 is connected to a front wheel a via a knuckle arm (not shown).

In the present invention, the tie rod 20, the knuckle arm and the like are collectively referred to as a steering link mechanism.

A pinion 21 is fixed to the rotor 10 of the rotary valve 9 and meshes with the rack 18.

A supply port 22 of the rotary valve 9 is connected to a hydraulic pump (not shown), and a discharge port 23 is connected to a tank (not shown).
5 is connected to two ports 26, 27 of the cylinder tube 15 by pipes 28, 29,
When 0 rotates in one direction, pressure oil is supplied to one side of the piston 16 and is discharged from the other side, and when rotated in the other direction, pressure oil is supplied to the other side of the piston 16 and discharged from one side. , The piston 16 operates together with the piston rod 17.

As described above, in the above-mentioned publication, in the present embodiment, the output shaft 31 of the control motor 30 such as a pulse motor mounted on a vehicle body (not shown) is connected to the handle 1 side drum. 7, and a detection device 32 for detecting the rotation angle of the handle 1 is attached to the handle 1.
An amplifier 33 for amplifying the signal transmitted from the detection device 32 and inputting the amplified signal to the control motor 30 is provided.

Next, the operation of this embodiment will be described.

When the steering wheel 1 is rotated in one direction, the rotation angle is detected by the detection device 32 and the signal is transmitted to the amplifier 3.
3, the signal is input to the control motor 30 and the output shaft 31 of the control motor 30 rotates by an angle corresponding to the handle 1, so that the drum 7 on the handle 1 rotates by the same angle as the handle 1 and the drum 7 rotates. One of the inner cables 6 of the two control cables 4 wound around the drum 7 on the steering position side is the drum 7 on the handle 1 side.
The inner cable 6 is fed out from the drum 7 on the steering position side, and the drum 7 and the rotating shaft 8 rotate in one direction. At this time, the inner cable 6 of the other control cable 4 is drawn out from the drum 7 on the handle 1 side and wound up on the drum 7 on the steering position side.

When the handle 1 is rotated in the other direction, the drum 7 on the steering position side and its rotating shaft 8 rotate in the other direction by the same operation.

When the rotating shaft 8 of the drum 7 at the steering position rotates in one direction, the rotor 10 connected thereto rotates in the same direction, and the engagement between the pinion 21 and the rack 18 causes the piston rod 17 to move in one direction. At this time, the rotation of the rotor 10 causes the rotary valve 9 to rotate.
Pressure oil is supplied from one of the ports 24, 25 to one of the ports 26, 27 of the power cylinder 14, the piston rod 17 operates in the same direction as described above, and the wheel a faces one via the steering link mechanism. .

When the rotation center shaft 8 of the drum 7 at the steering position rotates in the other direction, the wheel a faces the other by the same operation.

The tension of the inner cable 6 is adjusted by the nut 1
This is easily performed by loosening the 3 and rotating the cylindrical fixture 11.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of one embodiment of the present invention.

FIG. 2 is a perspective view of a drum according to one embodiment of the present invention.

FIG. 3 is a partially cutaway front view showing a control cable attachment length adjusting mechanism according to an embodiment of the present invention.

[Explanation of symbols]

 1: Handle 4: Control cable 5: Outer tube 6: Inner cable 7: Drum 9: Control valve 10: Rotor 14: Power cylinder 17: Piston rod 20: Tie rod 30: Control motor 32: Detector 33: Amplifier a: Front wheel

Claims (1)

[Claims] 1. A power cylinder having a piston rod connected at both ends to a front wheel via a steering link mechanism, and a direction control of pressure oil supplied to the power cylinder and simultaneously discharged from the power cylinder. A rotary control valve, a valve drum connected to a rotor of the control valve, a handle drum connected to a handle, and an inner cable slidably inserted into a flexible outer tube. A power steering device for an automobile, comprising: two control cables wound around the two drums so that a tensile force is applied alternately in the rotation of the handle-side drum in an alternating direction; Detecting means corresponding to the rotation angle of the handle detected by the detecting means; A power steering device for an automobile, comprising a control motor for rotating a drum on the side of a handle.