JPS61160359A - Power steering device - Google Patents

Abstract

PURPOSE:To make a device compact through electrically connecting a detection part to a motor so as to free the positional relation between both, by electrically detecting input from a handle and putting a motor, provided on the output side, in follow-up rotation corresponding to said detection. CONSTITUTION:When a handle 1 is operated in any direction, due to grounding resistance of a wheel 45, the rack 43 of a side rod 42 engaged with the pinion 40 of an input shaft 2 does not move instantly, and torsion is produced on the input shaft 2. Then the angle of torsion is electrically detected by means of the strain gauge of a detection part 3, and a motor 25 is driven by a control circuit 8 correspondingly to the angle of torsion and the direction of torsion. Thereupon, the pinion 44 of the motor 25 starts its rotation in the same direction as that of the pinion 40 of the input shaft 2 to put the rack 43 in movement and the side rod 42 in stroke, therefore, the wheel 45 is changed in its direction. Due to this structure, which does not impose restrictions on relative positions of the detection part 3 and the motor 25, an expected purpose can be attained.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention provides a power steering system for reducing the steering force of a vehicle.
The present invention relates to a 17 ringing device.

(Prior art) Ichishima Shi6hfpary-1 hand 1 voice Runo S! The input rotation from the handle is mechanically detected and the control pulp is actuated, which drives the hydraulic 7 actuator attached to the output shaft to follow the input rotation in the same direction as the input rotation, thereby converting the operating force of the handle into hydraulic pressure. The system is configured to reduce this by using power assist.

(Problems to be Solved by the Invention) However, in such a configuration, the structure for mechanically interlocking the input hearsay detection part and the control pulp is complicated, and the installation location is restricted, so power steering It was difficult to downsize and simplify the device.

In order to solve these problems, the present invention provides a power steering device that is compact and has a simple structure by electrically detecting the input from the steering wheel and following the rotation of the drive motor provided on the output side. The purpose is to

(Means for solving the problem α) Therefore, the present invention has been developed in Kawamuka's power steering device that power assists the turning force of the wheels according to the rotation of the steering wheel. A rack is provided that interlocks to change the direction of the wheels, and a detection section is attached to the input shaft that electrically detects the twist angle that occurs according to the difference between the steering input and the steering resistance, and based on the output of the detection section. The rack is provided with a drive motor that is reversibly driven by the rack, and the rotational force of the drive motor is transmitted to the rack via a pinion.

(Function) When the handle is rotated, the drive motor is driven in accordance with the rotational direction and rotational force, and the rack is moved in the same direction as the rotation of the handle by the pinion of the motor that meshes with the rack that is interlocked with the rotation of the handle. In addition, the turning operation of the single wheel is assisted by the motor drive force, reducing the steering force of the steering wheel.

(Example) Embodiments of the present invention will now be described based on the drawings.

In the figure, 1 is a handle, 2 is a steering input shaft, and a rotational force detection section 3 is provided in the middle of the input shaft 2. The detection unit 3 includes a strainage that electrically detects a twisting angle that occurs according to the difference between steering input and steering resistance when operating the steering wheel 1, and this strainage is designed to detect twisting angles in any direction of rotation. is attached to the input shaft 2 and electrically connected to form a Pritsuno circuit 7. 5a and 5b are conductive discs attached concentrically and insulated to the input shaft 2, and contact terminals 6a, 5b are attached to the outer circumference of the conductive discs.
6b are in elastic contact. One of the output terminals from the buritsuno circuit 7 is connected to the disk 5a and the other to the disk 5b, and therefore, there is a gap between these terminals 6a and 6b that is proportional to the twist angle of the input shaft 2 and depending on the rotation direction. It is designed to generate a potential difference reversibly. This output is input to a control circuit 8 consisting of an amplifier and the like.

On the other hand, the pinion 40 fixed to the tip of the input shaft 2 meshes with the hook 43 of the side rod 42 connected to the knuckle arms 41 of the left and right wheels 45, and moves the rack 43 left and right in accordance with the rotation of the handle 1. At the same time, a pinion 44 fixed to the rotation shaft 28 of the drive motor 25, which is reversibly rotated by the output of the control circuit 8, meshes with the rack 43. The rotation of this motor 25 is set to be in the same direction as the rotation of the input shaft 2, and the rotation operation force of the handle 1 is powered and assisted by the motor driving force.

With the above structure, when the handle 1 is moved in any direction, the side rod 42 engages with the pinion 40 of the input shaft 2 due to the ground resistance of the wheel 45.
The rack 43 does not move immediately, and as a result, the input shaft 2 instantaneously twists depending on the difference between the width of the input rotation and the ground resistance (turning resistance of the wheels 45). This twist angle is electrically detected by the strainage of the detection section 3, and the control circuit 8 rotates the drive motor 25 according to the twist angle and the twist direction. Therefore, the pinion 44 of the drive motor 25 starts rotating in the same direction as the pinion 40 of the input shaft 2, moving the hook 43 and stalling the side rod 42, thereby changing the direction of the wheel 45.

Then, when the handle 1 is stopped, the twist of the input shaft 2 disappears with a slight time lag due to the follow-up of the drive motor 25 with a certain time lag, and this causes the detection part 3 to disappear.
The output of the motor z5 becomes zero, the rotation of the motor z5 is stopped, and the wheel 45 is held at its inversion angle.

It will be easily understood that the turning operation described above is performed in the same manner regardless of the direction in which the handle 1 is rotated.

In the above embodiment, the rotation of the drive motor 25 may be transmitted to the pinion 44 in a decelerated state via a speed reduction mechanism, and it is also possible to provide a plurality of motors when the output is insufficient. In addition, the drive motor 25 is connected to input #I2.
For example, a gear may be fixed on an extension of the input shaft 2 and meshed with the pinion 44 of the drive motor 25 so as to directly transmit the rotational force from the input shaft 2 .

(Effects of the Invention) As described above, the present invention provides a rack that changes the direction of the wheels in conjunction with the input shaft to which the rotation of the steering wheel is transmitted, and the input shaft responds to the difference between the steering input and the steering resistance. A detection unit is installed to electrically detect the twist angle generated by the rotation, and a drive motor is reversibly driven based on the output of the detection unit, and the rotational force of this drive motor is transmitted to the rack via a pinion. As a result, the part of the input shaft that detects rotation and the motor that drives the rack can be connected by electrical connection, so there is no restriction on their relative positions, and it can be used in the narrow engine room of the vehicle or the wheels. It can be installed freely around the vehicle, making use of the features of the rack-binion power steering system, which is compact and has a small turning radius, and has the effect of simplifying the overall structure and reducing costs.

[Brief explanation of the drawing]

The drawings are schematic configuration diagrams showing embodiments of the present invention. 1... Handle, 2... Input shaft, 3... Detection section,
5a, 5b... Disc, 7... Bridge circuit, 8...
・Control channel (amplifier), 25... Drive motor, 28.
...rotating shaft, 40...pinion, 43...rack,
44...pinion, 45...wheel. Patent applicant: Kayaba Kogyo Co., Ltd.

Claims (1)

[Claims] In a power steering device for a vehicle that power assists the turning force of a wheel according to the rotation of a steering wheel, a rack that turns the direction of the wheel in conjunction with an input shaft to which rotation of the steering wheel is transmitted is provided, and the input shaft is provided with a rack that turns the wheel. A detection unit that electrically detects the twist angle that occurs depending on the difference between the input and steering resistance is installed, and a drive motor that is reversibly driven based on the output of the detection unit is provided, and the rack is equipped with a drive motor that is reversibly driven based on the output of the detection unit. A power steering device characterized in that rotational force is transmitted via a pinion.