JP2006273172A - Steering gear box mounting structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering gear box mounting structure for installing a steering gear box of a vehicular steering device to a vehicle body frame capable of facilitating the spacer mounting work and reducing the manufacturing cost. <P>SOLUTION: A first mounting part 17 and a second mounting part 18 are formed on a housing with a space therebetween. An circular hole 17p1 and a spacer mounting hole 17p2 are concentrically arranged in a mounting bolt insertion hole 17p of the first mounting part 17, and a long hole 18p1 long in the longitudinal direction of the housing and a spacer mounting hole 18p2 having the diameter larger than that of the long hole are formed in a mounting bolt insertion hole 18p of the second mounting part 18. A circular hole 20p having the diameter larger than that of the circular hole 17p1 and the long hole 19p1 is formed in a spacer 20, and the spacer can be mounted in the spacer mounting holes 17p2, 18p2 irrespective of the phase (direction) of the long hole 18p1. Since the spacer can be commonly mounted in any mounting hole, the manufacturing cost can be reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mounting structure for attaching a steering gear box to a vehicle or the like.

  As a steering device for a vehicle, a rack and pinion type steering device that transmits rotation of a pinion to a rack is widely used. In such a rack-and-pinion type steering device, a steering gear box having a structure in which a rotational force is transmitted from a pinion shaft to a rack shaft extending in a horizontal direction is used. As will be described later, the steering gear box refers to a mechanism in which a rack of a rack shaft and a pinion of a pinion shaft mesh with each other, and does not refer to a “housing” in which such a mechanism is assembled. In the following description, “housing” is referred to as “steering gear box housing” or simply “housing”.

  FIG. 3 is a front view for explaining the configuration of a conventional steering gear box. A rack shaft (not shown) is horizontally arranged inside the housing 101 of the cylindrical steering gear box 100. Both ends of the shaft are connected to tie rods 103 and 104. Further, a pinion housing 105 is provided in the housing 101 of the steering gear box 100, and a pinion shaft 106 is rotatably supported. Then, a pinion (not shown) of the pinion shaft 106 meshes with a rack (not shown), and the rotation of the pinion shaft 106 moves the rack shaft to the left and right to move the tie rods 103 and 104. The steering wheel is given a steering angle through no steering mechanism.

  In the steering gear box 100, the first mounting portion 107 and the second mounting portion 108 for fixing to the vehicle body frame are formed integrally with the housing 101, and are fixed to the vehicle body frame with two mounting bolts 2. It has a point support configuration.

  4 is also a front view illustrating the configuration of the conventional steering gear box 120. The same members as those shown in FIG. 3 are denoted by the same reference numerals, and detailed description thereof is omitted. In the configuration of FIG. The first mounting portion 111, the second mounting portion 112, the third mounting portion 113, and the fourth mounting portion 114 are formed integrally with the housing 101, and are fixed to the body frame with four mounting bolts. It has become.

  Recently, the housing 101 of the steering gear box 100 is usually made of an aluminum alloy for weight reduction. On the other hand, the body frame to which the housing 101 is attached is made of iron. Since the thermal expansion coefficient of aluminum alloy is larger than that of iron, even if the steering gear box is fixed to the body frame with an appropriate tightening margin when the ambient temperature during assembly at the factory is normal temperature, the vehicle remains at a high temperature. When exposed to the environment, in the configuration shown in FIG. 3, there is a dimensional deviation between the hole interval between the first attachment portion 107 and the second attachment portion 108 formed in the housing and the corresponding hole interval of the vehicle body frame. Occurs. The same problem occurs in the configuration shown in FIG.

  When the vehicle is repeatedly exposed to temperature changes, slipping occurs between the mounting part and the body frame, causing the mounting part to wear, gradually increasing wear and reducing the axial force of the mounting bolts of the mounting part. Loose bolts occur. In order to prevent loosening of the mounting bolt, it has been proposed to mount a spacer (see Patent Document 1).

Further, one of the mounting bolt insertion holes of the first mounting portion or the second mounting portion of the steering gear box housing is formed as an elongated hole in the longitudinal direction of the steering gear box, so that the expansion and contraction between the housing and the vehicle body frame is possible. There has been proposed a mounting structure configured to be able to absorb dimensional errors and manufacturing errors associated with the above (see Patent Document 2).
JP 2001-80528 A. JP 2004-168234 A.

  Hereinafter, the problem in the case of fixing the steering gear box to the sub-frame on the vehicle body side will be described with reference to the configuration shown in FIG. 3, but the same applies to the configuration shown in FIG. In the configuration shown in FIG. 3, spacers 107a and 108a are inserted into the mounting bolt insertion holes of the first mounting portion 107 and the second mounting portion 108 formed in the housing 101 of the steering gear box.

  FIG. 5 is a cross-sectional view for explaining a first example of the spacer mounting structure of the first mounting portion 107 and the second mounting portion 108, and FIG. 5A is along the axial center of the spacer 107 a of the first mounting portion 107. 5B is a plan view thereof, FIG. 5C is a cross-sectional view taken along the axial center of the spacer 108a of the second mounting portion 108, and FIG. 5D is a plan view thereof.

  The spacer 107a includes an upper spacer 107a1 and a lower spacer 107a2. The upper spacer 107a1 is attached to the attachment portion 107 from the upper side, and the lower spacer 107a2 is attached to the first attachment portion 107 from the lower side. The spacer 108a includes an upper spacer 108a1 and a lower spacer 108a2. The upper spacer 108a1 is attached to the second attachment portion 108 from the upper side, and the lower spacer 108a2 is attached to the second attachment portion 108 from the lower side.

  6 is a cross-sectional view for explaining a second example of the spacer mounting structure of the first mounting portion 107 and the second mounting portion 108, and FIG. 6A is a cross-sectional view of the mounting portion 107 along the axis of the spacer 107a. FIG. 6B is a plan view thereof, FIG. 6C is a cross-sectional view taken along the axial center of the spacer 108a of the attachment portion 108, and FIG. 6D is a plan view thereof.

  Each of the spacer 107a and the spacer 108a is a single cylindrical spacer, and the spacer 107a is attached to the first attachment portion 107 from above, and the spacer 108a is attached to the second attachment portion 108 from above. The outer peripheral edges of the end portions on the mounting side of the spacers 107a and 108a are chamfered to facilitate mounting.

  Assuming that the mounting reference when mounting the housing 101 of the steering gear box to the vehicle body frame is the first mounting portion 107, the mounting bolt insertion hole 107b of the spacer 107a of the first mounting portion 107 on the mounting reference side is formed as a circular hole. 2 The mounting bolt insertion hole 108b of the spacer 108a of the mounting portion 108 is formed as a long hole that is long in the longitudinal direction of the housing 101 (vertical direction in FIG. 5), and the mounting bolt insertion hole of the first mounting portion 107 and the second mounting portion 108 A dimensional error due to a work error or expansion / contraction due to a temperature change between the distance between and the corresponding distance between the mounting holes of the body frame is configured to be absorbed.

  However, according to the structure of the mounting portion of the steering gear box housing described above, it is necessary to prepare two types of spacer mounting bolt insertion holes, one formed as a circular hole and one formed as a long hole, In addition, when a spacer having a long hole is mounted on the mounting portion, it is necessary to mount the spacer so that the direction of the long hole coincides with the longitudinal direction of the housing. there were. An object of the present invention is to provide a steering gear box mounting structure that solves the above-described disadvantages.

  The present invention solves the above-mentioned problems, and the invention according to claim 1 is an attachment structure for fixing a steering gear box for a vehicle to a vehicle body frame, wherein the housing of the steering gear box has a predetermined interval in the longitudinal direction of the housing. A reference mounting portion that defines a mounting position on the vehicle body frame arranged at a distance from each other, and a mounting portion other than the reference mounting portion. A spacer mounted in the spacer mounting hole, and the mounting portion other than the reference mounting portion includes a long hole extending in the longitudinal direction of the steering gear box and a circular spacer disposed coaxially with the central axis of the long hole. A spacer mounted in the mounting hole is provided, and both the spacer mounted on the reference mounting portion and the spacer mounted on a mounting portion other than the reference mounting portion have the same dimensions. A mounting structure of the steering gear box, which is a spacer of cylindrical raised.

  The spacer can be mounted at an arbitrary angle around the central axis of the spacer mounting hole.

  Further, the length in the major axis direction of the long hole of the mounting portion other than the reference mounting portion is between the interval between the reference mounting portion and the mounting portion other than the reference mounting portion, and the interval between the mounting holes of the body frame. This is the length in the major axis direction that allows dimensional errors.

  Further, the long diameter of the long hole of the mounting portion other than the reference mounting portion is a length that allows a dimensional error based on a difference in thermal expansion between the housing of the steering gear box and the vehicle body frame.

  Further, it is preferable that the spacer has a rough surface at least in contact with the body frame to increase the coefficient of friction with the body frame. In this case, the surface is preferably subjected to a zinc phosphate coating treatment to finish the surface rough, and the coefficient of friction with the body frame is increased.

  As described in detail above, the steering gear box mounting structure according to the present invention includes a reference mounting portion that defines mounting positions on a vehicle body frame arranged at a predetermined interval in the longitudinal direction of the housing of the steering gear box, The reference mounting portion comprises a mounting portion other than the reference mounting portion, and the reference mounting portion includes a circular reference mounting hole and a spacer mounted in a spacer mounting hole arranged coaxially therewith. A long hole extending in the longitudinal direction of the steering gear box and a spacer mounted in a circular spacer mounting hole disposed coaxially with the central axis of the long hole are provided.

  Since the spacer mounted on the reference mounting portion and the spacer mounted on the mounting portion other than the reference mounting portion are both cylindrical spacers finished to the same dimensions, the spacer is mounted in the spacer mounting hole. Sometimes it is not necessary to consider the phase of the spacer, it can be mounted around the central axis of the spacer mounting hole at an arbitrary angle, and the major axis of the long hole is made to coincide with the longitudinal direction of the housing as in the conventional configuration Complex work can be saved.

  In addition, since the spacer is a common spacer that can be mounted on the reference mounting portion and also on a mounting portion other than the reference mounting portion, it has a remarkable effect such as being able to reduce the manufacturing cost. is there.

  Embodiments of the present invention will be described below. The overall configuration of the steering gear box according to the embodiment of the present invention is substantially the same as the configuration described above with reference to FIG. 3, and the difference is the configuration of the mounting portion. Therefore, the steering gear according to the embodiment of the present invention. The description of the overall configuration of the box is omitted, and the configuration of the mounting portion will be described below.

  FIG. 1 is a view for explaining the structure of a steering gear box mounting portion according to an embodiment of the present invention. The mounting portion is a reference mounting portion spaced apart in the longitudinal direction of a housing of a steering gear box (not shown). A certain first attachment portion 17 and a second attachment portion 18 that is an attachment portion other than the reference attachment portion are provided. The first attachment portion 17 and the second attachment portion 18 respectively correspond to the first attachment portion 107 and the second attachment portion 108 of the conventional configuration described above with reference to FIG.

  In the embodiment of the present invention, the spacers attached to the first mounting portion 17 and the second mounting portion 18 use members having the same dimensions. Hereinafter, the spacer will be described with reference numeral 20.

  1A is a sectional view of the first mounting portion 17 along the axis of the spacer 20, FIG. 1B is a plan view thereof, and FIG. 1C is a second mounting portion 18 of the spacer 20. A cross-sectional view along the axis, FIG. 1 (d) is a plan view thereof. FIG. 2 is an external view of the spacer 20 attached to the attachment portion.

  As shown in FIG. 1A, the first mounting portion 17 is formed in a portion protruding from the housing 11, and the mounting bolt insertion hole 17p that serves as a mounting reference when the housing is mounted on the vehicle body frame has a diameter. An α circular hole 17p1 and a spacer mounting hole 17p2 larger in diameter than the circular hole 17p1 having the diameter α are formed coaxially therewith.

  The second mounting portion 18 is also formed at a portion protruding from the housing 11, but the mounting bolt insertion hole 18p when mounting the housing to the vehicle body frame includes a long hole 18p1 having a long diameter k long in the longitudinal direction of the housing, and a long length. A circular spacer mounting hole 18p2 larger than the long diameter k of the long hole 18p1 is formed coaxially with the center of the hole 18p1.

  On the other hand, the spacer 20 has a configuration in which a flange 22 is provided on the lower side of the cylindrical member 21, as shown in FIG. The chamfer is chamfered to facilitate the press-fitting.

  The outer diameter of the spacer 20 is determined in consideration of a predetermined press-fitting allowance for the spacer mounting hole 17p2 or 18p2, and a circular hole 17p1 having a diameter α formed in the first mounting portion 17 is formed inside the spacer 20. A circular hole 20p having a diameter β larger than the long diameter k of the long hole 18p1 formed in the second mounting portion 18 is formed, and an unillustrated mounting bolt inserted into the inner surface of the circular hole 20p at the time of mounting It is configured so that some space remains between the outer diameters of the two.

  The spacer 20 finishes at least the surface abutting against the vehicle body frame to a rough surface, and increases the coefficient of friction to prevent loosening of the mounting bolts. In this case, the inner and outer surfaces of the spacer 20 are subjected to a surface finishing process such as a zinc phosphate coating process, and when the housing is attached to the body frame, the coefficient of friction with the body frame is increased to loosen the mounting bolts. In addition to preventing it, it is good to have a rust-preventing effect.

  When assembling the housing having the above configuration to the vehicle body, first, a mounting bolt (not shown) is inserted into the spacer 20 of the first mounting portion 17 of the housing serving as a mounting reference, and is loosely assembled to the vehicle body frame. Next, a mounting bolt (not shown) is inserted into the spacer 20 of the second mounting portion 18 of the housing and loosely assembled to the vehicle body frame. Further, the position is adjusted and the mounting bolt is tightened to complete the mounting.

  Since the mounting bolt insertion hole 18p of the second mounting portion 18 is formed as a long hole having a long diameter k that is long in the longitudinal direction of the housing, the mounting bolt hole on the vehicle body frame side and the mounting bolt insertion hole 18p of the second mounting portion 18 are formed. Even if there is a deviation in the allowable error range at the time of manufacturing, or a deviation in the allowable error range due to temperature change, it can be assembled without any problem.

  Further, since the spacer 20 having the above-described configuration is finished in a cylindrical shape and the same size, the phase (orientation) of the spacer is set when the spacer 20 is mounted in the spacer mounting hole 18p of the second mounting portion 18. There is no need to consider it, and it can be mounted at any angle around the center axis of the spacer mounting hole, so that the complicated work of matching the long diameter of the long hole in the longitudinal direction of the housing as in the conventional configuration can be omitted. it can.

  Furthermore, since one type of spacer can be used in common for the first and second mounting portions, the manufacturing cost of the spacer can be reduced.

  When assembling the housing of the steering gear box of the steering device for a vehicle to the frame of the vehicle body, a spacer is press-fitted into a plurality of mounting bolt insertion holes provided in the housing to prevent loosening of the mounting bolts. This is a steering gear box mounting structure in which spacers having the same dimensions are commonly used for holes, so that the spacer can be easily press-fitted and the manufacturing cost can be reduced.

The figure explaining the structure of the attaching part of the steering gear box of embodiment of this invention. The external view of the spacer with which an attachment part is mounted | worn. The front view explaining the structure of the conventional steering gear box (the 1). The front view explaining the structure of the conventional steering gear box (the 2). Sectional drawing explaining the 1st example of the mounting structure of the spacer of the 1st attaching part of the conventional steering gear box, and the 2nd attaching part. Sectional drawing explaining the 2nd example of the mounting structure of the spacer of the 1st attaching part of the conventional steering gear box, and a 2nd attaching part.

Explanation of symbols

11 Housing 17 First mounting portion 17p Mounting bolt insertion hole 17p1 Circular hole 17p2 Spacer mounting hole 18 Second mounting portion 18p Mounting bolt insertion hole 18p1 Long hole 18p2 Spacer mounting hole 20 Spacer

Claims (6)

In a mounting structure for fixing a steering gear box for a vehicle to a vehicle body frame,
The steering gear box housing includes a reference mounting portion that defines a mounting position on a vehicle body frame that is disposed at a predetermined interval in the longitudinal direction of the housing, and a mounting portion other than the reference mounting portion.
The reference mounting portion includes a spacer mounted in a circular reference mounting hole and a circular spacer mounting hole arranged coaxially therewith, and the mounting portions other than the reference mounting portion extend in the longitudinal direction of the steering gear box. A long hole and a spacer mounted in a circular spacer mounting hole disposed coaxially with the central axis of the long hole;
The steering gear box mounting structure, wherein the spacer mounted on the reference mounting portion and the spacer mounted on a mounting portion other than the reference mounting portion are cylindrical spacers finished to the same size. 2. The steering gear box mounting structure according to claim 1, wherein the spacer can be mounted around the central axis of the spacer mounting hole at an arbitrary angle. The major axis of the long hole of the mounting part other than the reference mounting part is a dimension that allows a dimensional error between the distance between the reference mounting part and the mounting part other than the reference mounting part and the distance between the mounting holes of the body frame. The steering gear box mounting structure according to claim 1, wherein the steering gear box mounting structure is provided. The long diameter of the long hole of the mounting part other than the reference mounting part is a dimension allowing a dimensional error based on a difference in thermal expansion between the housing of the steering gear box and the vehicle body frame. Steering gear box mounting structure. 2. The steering gear box mounting structure according to claim 1, wherein at least a surface of the spacer that contacts the vehicle body frame is roughened to increase a coefficient of friction with the vehicle body frame. 2. The steering gear box mounting structure according to claim 1, wherein a surface of the spacer is subjected to zinc phosphate coating treatment to increase a coefficient of friction between the spacer and the body frame. 3.

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