JP3623425B2 - Steering device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a steering apparatus that is assembled by tightening a lock nut to an end of an output shaft through a hole provided in a housing and then closing the hole with an end plug.
[0002]
[Prior art and problems to be solved by the invention]
Generally, in the steering device, the lower end of the output shaft inserted from above the housing is inserted into the inner ring of the rolling bearing in which the outer ring is fixed to the housing.
Next, after inserting the lock nut from the hole at the lower end of the housing, a special tool is inserted into the hole, and the lock nut is tightened to the threaded portion at the end of the output shaft.
Thereafter, the end plug is tightened into the hole using another tool to close the hole and fix the outer ring of the rolling bearing.
[0003]
However, a special tool for tightening the lock nut in the hole and a tool for tightening the end plug are required, and the tool needs to be replaced during assembly. For this reason, there exists a problem that assembly workability | operativity is bad.
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a steering apparatus with good assembling workability.
[0004]
[Means for Solving the Problems]
As a means for solving the problems to achieve the above object,
Aspects of the invention described in claim 1 includes an output shaft rotatably supported via the rolling bearings in the cylindrical housing, the inner race of the bearing are rolling rising in tightened to the threaded portion of the end portion of the output shaft A lock nut that is clamped between the outer peripheral step of the output shaft and fixed, a hole provided in the housing opposite to the end face of the lock nut, and a cylindrical shape surrounding the outer periphery of the lock nut. in steering apparatus and a end plug sandwiched and fixed between the inner peripheral surface screwed with the inner peripheral stepped portion outer ring of the rolling bearing of the housing with close the hole in the circumferential direction of the outer periphery of the lock nut An engagement protrusion formed on a part of the end plug and an engagement protrusion formed on a part of the inner periphery of the end plug and engageable with the engagement protrusion of the lock nut in the circumferential direction of the end plug. With end plug and lock nut It is characterized in that in a state in which the engaging projections engaged with each other are to manipulate tighten the lock nut by the end plug.
[0005]
In this configuration, the lock nut can be tightened using the end plug, so the special tool for tightening the lock nut that has been used in the past can be eliminated, and the tool is a single tool for turning the end plug. It will be better with only the tool. Moreover, since the tool engaged with the end plug for tightening the lock nut can be used as it is for tightening the end plug into the hole without removing it from the end plug, the assembling workability is remarkably improved.
[0006]
According to a second aspect of the present invention, in the first aspect, the engagement protrusion of the lock nut includes a circumferential stopper that engages with the engagement protrusion of the end plug in the circumferential direction, an engagement protrusion of the end plug, and a shaft. And an axial stopper engaged in the direction.
According to a third aspect of the present invention, in the first or second aspect of the present invention, when the lock nut is tightened by the end plug, the screw hole on the outer periphery of the end plug does not interfere with the hole in the housing. The height position of the thread portion is set with respect to the insertion direction.
In this configuration, when the lock nut is tightened by the end plug, since the threaded portion on the outer periphery of the end plug does not interfere with the hole of the housing, the tightening operation can be performed smoothly. After completing the tightening of the lock nut, the engagement between the end plug and the lock nut is released, the end plug is inserted deeper into the hole, and only the end plug is rotated to move to the inner peripheral surface of the hole in the housing. Can be screwed in.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic cross-sectional view showing a main part of a steering apparatus according to an embodiment of the present invention.
Referring to FIG. 1, an output shaft 1 on which a pinion 1a is formed is rotatably supported in a housing 4 by rolling bearings 2 and 3, and a rack shaft 5 is supported by a bearing member (not shown) in the axial direction direction (on the paper surface). It is supported so as to be movable along (perpendicular direction).
[0008]
The output shaft 1 and the rack shaft 5 are meshed with each other in the housing 4. Although not shown, both ends of the rack shaft 5 are connected to the steering wheel via tie rods, and the rack shaft 5 moves in the axial direction along with the rotation of the steering wheel (not shown) to perform the steering. . The torsion bar 6 connects the input shaft that rotates integrally with the steering wheel and the output shaft 1 described above.
The housing 4 is provided with a cylindrical portion 7 on the opposite side of the output shaft 1 across the rack shaft 5, and the rack 7 is energized by a compression coil spring 9 in the accommodation hole 8 of the cylindrical portion 7. A support yoke 10 that supports the shaft 5 is slidably accommodated.
[0009]
An end 11 of the output shaft 1 is inserted through the rolling bearing 3, and a lock nut 13 is fastened to a screw portion 12 formed at the end 11. The lock nut 13 fixes the end 11 of the output shaft 1 to the inner ring 14 of the rolling bearing 3.
Further, the housing 4 is provided with a hole 15 facing the end face of the lock nut 13, and an end plug 17 is screwed into the threaded part 16 on the inner peripheral surface of the inlet part of the hole 15 to close the hole 15. . Further, the end plug 17 fixes the outer ring 18 of the rolling bearing 3 to the housing 4.
[0010]
The feature of this embodiment is that the end plug 17 and the lock nut 13 can be engaged with each other so that the lock nut 13 can be tightened by the end plug 17.
That is, FIG. 2 is an exploded perspective view of the end plug 17 and the lock nut 13 and is shown upside down with respect to the assembled state. Referring to FIG. 2, the lock nut 13 has a cylindrical body 13 a having a screw hole 19 that is coupled to the screw portion 12 of the end portion 11 of the output shaft 1. One or more engaging protrusions 20 are formed on the upper portion of the outer peripheral surface of the cylindrical body 13a in the figure.
[0011]
The engagement protrusion 20 has a first portion 21 that extends in the axial direction from the upper end in the figure of the cylindrical body, and second portions 22 and 22 that extend in the circumferential direction on the left and right of the lower end of the first portion 21. It has an inverted T shape.
On the other hand, the end plug 17 has a cylindrical peripheral side wall 23, an end wall 24 that closes the end of the peripheral side wall 23, and a hexagonal columnar head 25 formed on the end wall 24. Yes. One or more engaging protrusions 26 respectively corresponding to the engaging protrusions 20 of the lock nut 13 are formed on the lower part of the inner peripheral surface 23a of the peripheral side wall 23 so as to extend radially inward. The inner diameter of the peripheral side wall 23 of the end plug 17 is set to a size capable of introducing the lock nut 13 with the engagement protrusion 20.
[0012]
In FIG. 2, a stepped portion having a saddle shape is formed by a circumferential stopper 27 formed by the side surface of the first portion 21 of each engagement protrusion 20 of the lock nut 13 and an axial stopper 28 formed by the upper surface of the second portion 22. Each is formed, and the engagement protrusion 26 of the end plug 17 corresponding to this stepped portion is engaged. That is, the engagement protrusion 26 of the end plug 17 engages with the axial stopper 28 to restrict displacement in one axial direction, while it engages with the circumferential stopper 27 and is locked by the end plug 17. 13 can be rotated.
[0013]
Further, a screw portion 29 to be screwed into the screw portion 16 on the inner peripheral surface of the hole 25 is formed at the upper portion in the drawing of the outer peripheral surface of the peripheral side wall 23 of the end plug 17. The height position of the screw portion 29 is set so that the screw portion 29 does not interfere with the screw portion 16 of the hole 15 of the housing 4 when the lock nut 13 is tightened by the end plug 17.
A procedure for assembling the lock nut 13 and the end plug 17 will be described with reference to FIGS. 3A to 3C and FIGS. 4A to 4C, which are schematic cross-sectional views.
[0014]
First, as shown in FIG. 3A, the end portion 11 of the output shaft 1 is inserted into the rolling bearing 3.
Next, as shown in FIG. 3 (b), the lock nut 13 is inserted into the hole 15 of the housing 4 with the engaging protrusions 26 of the end plug 17 engaged with both stoppers 27, 28 of the lock nut 13. Then, by turning the head 25 of the end plug 17 with a tool such as a spanner, the lock nut 13 is fastened to the screw portion 12 of the end portion 11 of the output shaft 1 as shown in FIG. Thereby, the end 11 of the output shaft 1 is fixed to the inner ring (not shown) of the rolling bearing 3 by the lock nut 13.
[0015]
Since the height position of the screw portion 29 is sufficiently high, the screw portion 29 of the end plug 17 is connected to the inlet edge of the hole 15 of the housing 4 even when the lock nut 13 is tightened as shown in FIG. It does not interfere with the screw part 16 of the part.
Next, as shown in FIG. 4A, the end plug 17 is rotated at a rotation angle of, for example, several degrees in a direction opposite to that when the lock nut 13 is tightened, and the engagement protrusion 13 and the engagement protrusion 20 are rotated. After releasing the engagement between the end plug 17 and the end plug 17, the end plug 17 is displaced toward the back of the hole.
[0016]
Then, the screw portion 29 on the outer periphery of the end plug 17 is screwed into the screw portion 16 on the inner periphery of the hole 15 to close the hole 15 with the end plug 17 and to fix the outer ring (not shown) of the rolling bearing 3.
From the operation of tightening the lock nut 13 using the end plug 17 to the operation of tightening the end plug 17 in the hole 15, it can be performed consistently with a single tool fitted to the head 25 of the end plug 17. Workability is greatly improved. In addition, a special tool for tightening a lock nut that has been conventionally used can be eliminated.
[0017]
The present invention is not limited to the above-described embodiment. For example, the means for engaging the end plug and the lock nut with each other includes an engagement protrusion provided on one side and an engagement provided on the other side. It may be a concavity, and various other modifications can be made within the scope of the present invention.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing a schematic configuration of a steering apparatus according to an embodiment of the present invention.
FIG. 2 is a partially broken exploded perspective view of a lock nut and an end plug.
FIGS. 3A to 3C are schematic cross-sectional views sequentially showing an operation of tightening a lock nut using an end plug.
FIGS. 4A to 4C are schematic cross-sectional views sequentially showing the operation of tightening the end plug after being used for tightening the lock nut into the hole of the housing.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Output shaft 1a Pinion 2, 3 Rolling bearing 4 Housing 5 Rack shaft 11 End part 12 Screw part 13 Lock nut 13a Cylindrical body 14 Inner ring 15 Hole 16 Screw part 17 End plug 18 Outer ring 19 Screw hole 20, 26 Engagement protrusion (engagement) Means to match)
21 1st part 22 2nd part 23 Peripheral side wall 24 End part wall 25 Head part 27 Circumferential direction stopper 28 Axial direction stopper 29 Thread part

Claims (3)

An output shaft rotatably supported via a rolling bearing in a cylindrical housing;
And a lock nut to a stopping and sandwiched between the outer peripheral step portion of the output shaft to the inner race of the output shaft end of the bearing are rolling rising in tightened to the threaded portion of,
A hole provided in the housing opposite the end face of the lock nut;
It has a cylindrical shape that surrounds the outer periphery of the lock nut, and includes an end plug that is screwed into the inner peripheral surface of the hole to close the hole and that fixes the outer ring of the rolling bearing between the inner peripheral step portion of the housing. In the steering device,
Engagement protrusions formed on a part of the outer periphery of the lock nut;
An engagement protrusion formed on a part of the inner periphery of the end plug, and engageable with the engagement protrusion of the lock nut in the circumferential direction of the end plug;
Steering apparatus characterized by the engagement projections of the end plugs and a lock nut in a state of being engaged with each other are to manipulate tighten the lock nut by the end plug. The engagement protrusion of the lock nut includes a circumferential stopper that engages with the engagement protrusion of the end plug in the circumferential direction, and an axial stopper that engages with the engagement protrusion of the end plug in the axial direction. The steering device according to claim 1. When tightening the lock nut with the above end plug, the height of the threaded part should be set with respect to the direction of insertion into the end plug hole so that the threaded part on the outer periphery of the end plug does not interfere with the hole in the housing. The steering apparatus according to claim 1 or 2, characterized in that.

Images