JPH0546546Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a rack and pinion type steering device used as a steering device for automobiles, etc. In particular, a hollow rack shaft that engages with a pinion is provided in a housing so as to be movable in a reciprocating manner. This invention relates to a rack and pinion type steering device in which a ball joint is screwed and fixed to both ends of a hole, and the left and right bellows surrounding the ball joint are communicated through the hollow hole of the rack shaft.

As this kind of rack and pinion steering device, the third
As shown in the figure, a hollow rack shaft 1 that engages with a pinion 2 is provided in a housing 4 so as to be able to reciprocate, and the screw portions 7 of a ball joint 5 are screwed into both ends of the rack shaft to fix the rack shaft 1. A communication hole 11 extending from the outer periphery of the rack shaft to the hollow hole thereof is provided at the end of the rack shaft, and the inside of the bellows 8 is communicated with the hollow hole of the rack shaft through this communication hole 11. It is known that the left and right bellows are connected to each other. Incidentally, in order to protect the ball joint 5, the volume of the bellows, which is provided to surround the ball joint 5, changes as the rack shaft 1 reciprocates, so it is necessary to keep the left and right bellows in communication with each other. There is. As mentioned above, the structure in which the insides of the left and right bellows are communicated using the hollow hole in the rack shaft has the advantage that piping for communication can be omitted.

As described above, when the rack shaft is provided with a communication hole extending from its outer periphery to the hollow hole to communicate the interior of the bellows with the hollow hole of the rack shaft, the following problems arise. That is, at one end of the housing the pinion 2
a rack guide 3 pressing the rack shaft 1,
An appropriate amount of grease is applied to each sliding surface of the rack bushing 12 supporting the rack shaft at the other end in order to smooth the reciprocating movement of the rack shaft. The communication hole 1
There was a fear that 1 would be blocked and its function would be impaired. If this communication hole 11 is blocked by grease, the fluidity of the air within the bellows 8 will deteriorate during steering operations, resulting in heavy steering operation and discomfort to the driver. Further, providing the communication hole 11 in the hollow rack shaft 1 has the problem that the bending load resistance of the rack shaft 1 is reduced.

The present invention was developed in consideration of these points, and is a rack and pinion type steering system that prevents clogging of the communication hole due to the inflow of grease, allows easy steering operation at all times, and does not impair the strength of the rack shaft. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be described below based on embodiments shown in the accompanying drawings.

Figures 1 and 2 show an embodiment of the present invention.
In the drawing, ball joints 5 are screwed and fixed to both ends of the rack shaft 1 via stopper members 13. In the threaded portion 7 of this ball joint 5,
A first communication hole 10 extending in the axial direction from its tip
is provided. A second communication hole 14 is provided in the hexagonal portion 9 of the ball joint 5 to open the first communication hole 10 between the stopper member 13 and the main body 6 of the ball joint 5. Therefore, the grease applied to the rack shaft 1 is stopped by the stopper member 13, and the grease applied to the rack shaft 1 is stopped by the second communication hole 14 provided in the hexagonal part 9.
The inside of the bellows 8 and the hollow hole of the rack shaft 1 always communicate with each other, so that a light handle operation can be obtained.

As described above, the present invention prevents clogging of the communication hole due to the inflow of grease in a rack and pinion type steering device in which the insides of the left and right bellows communicate with the hollow hole of the rack shaft, and constantly connects the inside of the bellows with the rack shaft. The rack shaft communicates with the hollow hole of the shaft, allowing for easy handle operation, and since the rack shaft itself is not provided with a communication hole, the strength of the rack shaft is ensured.

[Brief explanation of the drawing]

Figures 1 and 2 show an embodiment of the present invention.
FIG. 1 is a sectional view of the main part, FIG. 2 is a front view of the main part seen from above in FIG. 1, and FIG. 3 is a sectional view showing a conventional example. Explanation of symbols, 1...Rack shaft, 2...Pinion, 3...Rack guide, 4...Housing, 5
...Ball joint, 6...Body of ball joint, 7...Thread section, 8...Bellows, 9...
Hexagonal part, 10...first communication hole, 13...stopper member, 14...second communication hole.

Claims (1)

[Scope of utility model registration request] A hollow rack shaft 1 that engages with the pinion 2 is provided in the housing 4 so as to be reciprocally movable, and ball joints 5 are screwed and fixed to both ends of the hollow hole of the rack shaft. In a rack and pinion type steering device in which left and right bellows 8 surrounding a ball joint 5 communicate with each other, the ball joint 5 is screwed and fixed to the rack shaft 1 via a stopper member 13, and the ball joint 5 is screwed. A first communication hole 10 is provided in the portion 7 extending in the axial direction from its tip, and facing the first communication hole 10, the first communication hole 10 is connected between the stopper member 13 and the main body 6 of the ball joint 5. 2nd open between
A rack and pinion type steering device characterized in that a communication hole 14 is provided to communicate a hollow hole of the rack shaft with the inside of the bellows.