JP2548159Y2 - Rack and pinion type steering device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rack and pinion type steering device.

[0002]

2. Description of the Related Art In a rack and pinion type steering device,
As shown in FIG. 2, the pinion teeth formed on the pinion shaft 11 rotated by the handle operation and the rack teeth formed on the rack shaft 12 connected to the wheels mesh with each other in the gear housing 10. A resin sheet 1 made of a low-friction material is provided on the meshing portion from the opposite side of the rack shaft 12 where the rack teeth are provided.
5 is brought into contact with the rack guide 14 and the rack shaft 12
The pinion teeth and the rack teeth are meshed with a predetermined meshing force by the pressing force of the spring 16 between the spring retainer 17 provided on the gear housing 10 and the rack guide 14.

When the pinion shaft 11 is rotated by operating the handle, the rotation of the pinion shaft 11 is transmitted to the rack shaft 12 via the meshing portion, and the rack shaft 12 makes a sliding motion. The rack guide 14 and the rack shaft 1 generated at that time
The relative movement between the two is guided by the slip of the resin sheet 15 inserted between them. In the method of guiding the relative movement by sliding, the sheet 15 is made of a resin having a small friction coefficient, but the sliding resistance at this time has a considerably large value. Since the sliding movement of the rack guide 14 and the rack shaft 12 is performed against the slip resistance, when the rack shaft 12 is slightly moved by applying a small torque to the handle, there is a case where the steering cannot be smoothly performed. is there.

In order to reduce the resistance between the rack guide 14 and the rack shaft 12, as shown in Japanese Patent Publication No. 45-23041, a roller member is rotatably mounted on the rack guide, There is known an apparatus in which a rack shaft is supported by a small rolling resistance.

[0005]

However, during the sliding movement of the rack shaft, the roller member has not only the force in the sliding direction of the rack shaft but also the teeth generated by the meshing of the pinion teeth and the rack teeth. An axial thrust force of the roller member acts on the roller member due to the twist and the action from the tires at both ends of the rack shaft. Due to the axial thrust force of the roller member, sliding resistance occurs between the roller member and the rack guide, and this sliding resistance affects the rolling resistance of the roller member, and the rack shaft may not be smoothly steered. There is.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. A gear shaft is slidably provided on a gear housing, and a meshing portion between the pinion shaft and the rack shaft is provided on the gear housing. A cylinder guide is formed on the opposite side of the rack guide. A rack guide for pressing the rack shaft is inserted into the cylinder hole, and the rack guide is rotated around a pin provided on the rack guide at a position where the rack guide comes into contact with the rack shaft. A rack-and-pinion type steering device in which a roller guide is provided so as to be supported, and a spring is interposed between the rack guide and a spring retainer fixed to the gear housing. interposed a bearing, the low this slide bearing
A pair of slide bearings are arranged on both axial sides of the
A cylinder inserted between the roller guide and the pin
Part and the end of this cylindrical part
Between the end face of the roller guide and the end face of the rack guide.
And a collar portion interposed therebetween .

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 10 denotes a gear housing, on which a pinion shaft 11 rotated by a handle (not shown) is rotatably supported. Pinion teeth 11 a are formed on the pinion shaft 11, and the pinion teeth 11 a mesh with rack teeth 12 a formed on the rack shaft 12. The rack shaft 12 is slidably fitted in the gear housing 10, and wheels (not shown) are connected to both ends.

[0008] A cylinder hole 13 is formed in the gear housing 10 on the opposite side of the rack shaft 12 with respect to the meshing portion of the rack shaft 12 and the pinion shaft 11, and the cylinder hole 13 receives the rack shaft 12. Metal rack guide 14
Is inserted. A rack retainer 17 is screwed into the open end of the cylinder hole 13, and a rack guide 14 is provided between the rack retainer 17 and the rack guide 14.
A spring 16 that presses toward 2 is inserted.
The pressing force of the spring 16 causes the pinion teeth 11 a of the pinion shaft 11 and the rack teeth 12 of the rack shaft 12 to move.
a mesh with a predetermined meshing force.

A pin 21 is fixed to the rack guide 14 in parallel with the axis of the pinion shaft 11. A cylindrical steel roller guide 20 having a concave cylindrical surface is rotatably supported around the pin 21. The concave cylindrical surface is in contact with the rack shaft 12. Further, the roller guide 20 is provided between the pin 21 and the sliding bearing 2 made of two low friction materials.
2 is inserted. Each of the plain bearings 22 has a cylindrical portion 23 inserted between the roller guide 20 and the pin 21 to rotatably support the roller guide 20 around the pin 21, and one end of the cylindrical portion 23. A flange 24 is provided and inserted between the end of the roller guide 20 and the rack guide 14. The collar 24 generates the pinion teeth 11 a and the rack teeth 12 a torsion of the teeth and the tires at both ends of the rack shaft 12. The roller guide 20 receives an axial thrust force generated by the action of the roller guide 20.

Next, the operation based on the above configuration will be described. When the operation of the steering wheel is started and the pinion shaft 11 rotates, the rotation of the pinion shaft 11 is transmitted to the rack shaft 12, and the rack shaft 12 reciprocates. At this time, the meshing portion between the rack shaft 12 and the pinion shaft 11 is pressed by the rack guide 14 from the opposite side of the rack shaft 12 so as to mesh with a predetermined meshing force. The part where the rack guide 14 presses the rack shaft 12 is connected to a pin 21 by a sliding bearing 22.
And a roller guide 20 rotatably supported through the roller guide 20. Therefore, when the rack shaft 12 reciprocates, the rotational resistance of the roller guide 20 rotating around the pin 21 is much smaller than the conventional sliding resistance generated between the roller sheet 20 and the resin sheet 15, and the rack shaft 12 has a pinion. It is possible to slide smoothly by the action of a small torque from the shaft 11, and therefore, the movement of the tire to the operation of the steering wheel can be made sensitive.

Further, during the sliding movement of the rack shaft 12,
A thrust force acts in the axial direction of the roller guide 20 due to the torsion of the teeth and the action from the tires at both ends of the rack shaft.
The thrust force is received by the flange portions 24 located at both ends of the slide bearing 22, and the sliding resistance between the rack guide 14 and the roller guide 20 caused by the thrust force can be reduced. It can be prevented that the rolling resistance of the guide 20 is affected and the rack shaft 12 cannot move smoothly.

[0012]

[Effects of the Invention] As described above, the present invention is a roller guide.
Insert a slide bearing between
A pair of rollers are arranged on both sides in the axial direction of the roller guide.
Cylindrical part with bearing inserted between roller guide and pin
And is integrally bent and formed from the end of this cylindrical part.
Between the roller guide end face and the rack guide end face.
Since it is configured by a flange portion which, rotational resistance of the roller guide when the rack shaft reciprocates is very small, the roller guide can be smoothly rotated, the rack shaft is under the action of a small torque from the pinion shaft It can slide smoothly. Further, since the slide bearing is provided with a flange portion for supporting the axial thrust force of the pin, the sliding resistance between the rack guide and the roller guide caused by the axial force of the roller guide can be reduced. it can. In addition, the present invention provides a radial and roller guide.
Reduce the number of sliding bearing parts supported in the thrust direction
To reduce the cost of the rack guide mechanism.
And a pair of sliding bearings from both ends of the roller guide
Since it is only necessary to assemble, it is possible to greatly improve
There is fruit.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a portion where a rack gear and a pinion gear mesh with each other according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a conventional art, in which a rack gear and a pinion gear mesh with each other.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Gear housing 11 Pinion shaft 12 Rack shaft 13 Cylinder hole 14 Rack guide 16 Spring 17 Spring retainer 20 Roller guide 22 Slide bearing 23 Cylindrical part 24 Collar part

Claims (1)

(57) [Scope of request for utility model registration] A gear shaft is slidably provided in a gear housing, and a cylinder hole is formed in the gear housing on a side opposite to a meshing portion between the pinion shaft and the rack shaft. A rack guide that presses the rack shaft is inserted, and a roller guide rotatably supported around a pin provided on the rack guide is provided at a position where the rack guide comes into contact with the rack shaft. In a rack and pinion type steering device in which a spring is inserted between spring retainers fixed to the gear housing, a slide bearing is inserted between the roller guide and the pin, and the slide bearing is connected to the low bearing.
A pair of slide bearings are arranged on both axial sides of the
A cylinder inserted between the roller guide and the pin
Part and the end of this cylindrical part
Between the end face of the roller guide and the end face of the rack guide.
A rack-and-pinion type steering device comprising a collar portion interposed therebetween.