JPH0622156U - Power steering device - Google Patents

Abstract

(57) [Abstract] [Purpose] The cylinder rod 3 and the bush 20 and the bush 20 and the stopper cylinder end 7 collide with each other due to vibration in the radial direction input from the traveling wheel to the cylinder rod 3, and a striking sound is generated. [Structure] Annular grooves 15 and 16 are formed between the stopper cylinder end 7 and the bush 20 on the stopper cylinder end 7 side and between the bush 20 and the cylinder rod 3 on the bush 20 side, respectively. Power steering device.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a power steering device, and more particularly to a stopper cylinder end of a power cylinder of the power steering device.

[0002]

[Prior art]

 In the conventional power steering apparatus, as shown in FIG. 3, a stopper cylinder end 52 is fitted and screwed to the tip of the power cylinder 50, and the stopper cylinder end 52 is connected to the power cylinder. It is composed of a rod guide portion 53 fitted in the cylinder 50 and an outer cylindrical portion 55. A guide hole 57 is formed in the rod guide portion 53, and an annular groove 60 into which a bush 59 is fitted is formed on the inner peripheral surface of the guide hole 57. The cylinder rod 62 is inserted into the bush 59 with grease lubrication. Has been done.

[0003]

[Problems to be solved by the device]

 In the above conventional technique, due to the accuracy error of the cylinder rod 62, the bush 59, and the stopper cylinder end 52, the clearance between the cylinder rod 62 and the bush 59 and the clearance between the bush 59 and the stopper cylinder end 52. Grows larger. Then, the vibration of the cylinder rod 62 in the radial direction causes a striking sound due to the collision between the cylinder rod and the bush and between the bush and the stopper cylinder end. However, it is difficult to reduce the clearance of each because it consists of three parts. Further, since the grease between the cylinder rod 62 and the bush 59 flows due to the operation of the cylinder rod 62, there is a problem that the impact sound gradually increases.

[0004]

[Means for Solving the Problems]

 A stopper cylinder end formed with a guide hole for slidably guiding the cylinder rod is fixed to the end of the power cylinder, and a bush is fitted to the inner circumference of the inner hole of the stopper cylinder end to fix the bush. An annular groove for filling grease is formed on the inner peripheral surface of the guide hole of the fitted stopper cylinder end, or a guide hole for slidably guiding the cylinder rod is formed at the end of the power cylinder. The stopper cylinder end is fixed, a bush for inserting the cylinder rod is fitted on the inner periphery of the guide hole of the stopper cylinder end, and an annular groove for filling with grease is formed on the inner peripheral surface of the bush.

[0005]

[Action]

 The grease filled in the annular groove formed on the inner peripheral surface of the stopper cylinder end and the annular groove formed on the inner peripheral surface of the bush should be between the bush and the stopper cylinder end, and between the bush and the cylinder rod. Break into. This grease alleviates the collision between the bush and the stopper cylinder end, and between the bush and cylinder rod. Further, since the annular groove is filled with grease, the grease is maintained for a long time.

[0006]

【Example】

 An embodiment of the present invention will be described with reference to FIGS. 1 and 2. In FIG. 1, a rack-and-pinion type power steering device is shown as an example of the power steering device, and in the device, appropriate portions are coaxial wires in the housing 1 supported by a frame (not shown) and at the end of the housing 1. A cylinder rod 3 is axially movably inserted into the power cylinder 2 which is fixed in an extended relationship. Both ends (not shown) of the cylinder rod 3 are connected to traveling wheels via ball joints.

Further, a rack 5 that meshes with a pinion 4 of a pinion shaft that is coupled to the handle shaft via a servo valve device is formed in an intermediate portion of the cylinder rod 3. A piston 6 movably fitted in the power cylinder 2 is fixed to the cylinder rod 3 while being driven by a rotating operation in the axial direction.

Further, as shown in FIG. 2, a stopper cylinder end 7 is screwed into the tip of the power cylinder 2, and a collar 14 is attached to the piston 6 side of the stopper cylinder end 7. The oil seal 13 is fitted in through. The stopper cylinder end 7 is composed of a rod guide portion 8 fitted in the power cylinder 2 and an outer cylindrical portion 9, and an end surface of the power cylinder 2 comes into contact with a step portion 10 on the outer peripheral surface of the boundary, so that the power cylinder 2 An O-ring 11 seals between the inner peripheral surface of the rod and the outer peripheral surface of the rod guide portion 8.

A guide hole 12 is formed in the rod guide portion 8, an annular groove 15 for accommodating grease is formed on the inner peripheral surface of the guide hole 12, and a bush 20 is fitted inside the groove 15. Has been. The grease is lubricated between the bush 20 and the stopper cylinder end 7. A cylinder rod 3 is slidably fitted into the bush 20 and an annular groove 16 is formed on the inner peripheral surface of the bush 20 on the cylinder rod 3 side. The annular groove 16 is filled with grease, and the space between the bush 20 and the cylinder rod 3 is lubricated with grease.

The operation of the above rack and pinion type power steering apparatus, particularly the operation of the rod guide portion 8, will be described. The pinion 4 rotates due to the steering rotation of the handle shaft, and the rack 5, that is, the cylinder rod 3 moves left and right in the axial direction, and at the same time hydraulic oil acts on the power cylinder 2 by the servo valve device, and hydraulic operation is performed on the left and right movements of the cylinder rod 3. Added. Accordingly, the traveling wheels on both ends of the cylinder rod 3 are deflected in a desired direction. When the cylinder rod 3 moves in the axial direction, the cylinder rod 3 is guided by the guide hole 12 of the rod guide portion 8 and slides in the bush 20.

The cylinder rod and the bush and the bush and the cylinder end collide with each other due to the radial vibration input from the traveling wheel to the cylinder rod 3. However, since each part is lubricated with grease, this grease alleviates the collision.

[0012]

[Effect of device]

 According to this invention, an annular groove for filling the stopper cylinder end side with grease is formed between the stopper cylinder end and the bush, or an annular groove for filling the bush side with grease is formed between the bush and the cylinder rod. Since the groove is formed, collision between the bush and the stopper cylinder end and between the bush and the cylinder rod is mitigated, so that the impact sound generated is reduced.

Further, the grease is filled in the annular groove to retain the grease for a long period of time. There are advantages.

[Brief description of drawings]

FIG. 1 is a partial sectional view of a rod guide portion of a rack-and-pinion type power steering apparatus according to this embodiment.

FIG. 2 is a sectional view of a rod guide portion in FIG.

FIG. 3 is a partial sectional view of a rod guide portion of a rack and pinion type power steering apparatus according to a conventional technique.

[Explanation of symbols]

 2 Power Cylinder 3 Cylinder Rod 4 Pinion 5 Rack 6 Piston 7 Stopper Cylinder End 8 Rod Guide 9 Cylindrical 12 Guide Hole 13 Oil Seal 14 Collar 15, 16 Annular Groove 20 Bush

Claims (2)

[Scope of utility model registration request] 1. A power steering apparatus, wherein a cylinder rod moved axially through a rack and a pinion by steering a steering wheel is inserted into a power cylinder, and the power cylinder applies hydraulic operation to the cylinder rod to perform steering. A stopper cylinder end having a guide hole for slidably guiding the cylinder rod is fixed to the end of the power cylinder, and a bush is fitted to the inner circumference of the guide hole of the stopper cylinder end, and the bush is fitted. A power steering apparatus characterized in that an annular groove for filling grease is formed on an inner peripheral surface of a guide hole of a stopper cylinder end which is attached. 2. A power steering apparatus, wherein a cylinder rod moved axially through a rack and a pinion by steering a steering wheel is inserted into a power cylinder, and the power cylinder applies hydraulic operation to the cylinder rod to perform steering. A stopper cylinder end having a guide hole for slidably guiding the cylinder rod is fixed to the end of the power cylinder, and a bush for inserting the cylinder rod is fitted to the inner circumference of the guide hole of the stopper cylinder end. A power steering apparatus is characterized in that an annular groove for filling grease is formed on the inner peripheral surface of the bush.