JPH0635859Y2 - Rack gear case mounting structure for steering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a structure in which a rack gear case in a rack and pinion steering device is mounted on a vehicle body through a mounting bracket, and particularly without increasing the number of parts. The present invention relates to a structure capable of improving the mounting rigidity of a rack gear case.

[Conventional technology]

The steering device is a device that changes the traveling direction of the vehicle to the left or right, and this changes the rotation of the steering wheel into an axial movement by, for example, a pinion connected to the lower end of the steering shaft and a rack shaft with which it meshes. It is configured to convert and thereby steer the front wheels. A rack gear case is generally attached to the rack shaft, and the case is generally fixed to a vehicle body through a mounting bracket. As a mounting structure for such a rack gear case, the conventional structure shown in FIGS. There is something like.

In the figure, reference numeral 1 denotes a rack gear case, which is a gear box 3 for accommodating a pinion portion connected to a lower end of a steering shaft 2, a case bracket 4 formed integrally with the box 3, and a rack extending in the vehicle width direction. A rack tube 6 that houses the shaft 5, and the tube 6
And a case bracket 7 attached in the middle of the. The case brackets 4 and 7 are substantially semi-circular when viewed in the axial direction, the bottom surfaces 4b and 7b are formed flat, and a pair of flange portions 4a and 7a are integrally formed on both side surfaces. Has been formed. The bottom portions of the flange portions 4a, 7a are flush with the bottom surfaces 4b, 7b, and the flange portions 4a, 7a
Bushings 8 are fitted between 4a and between 7a and 7a.

When mounting the rack gear case 1 on the vehicle body, the case brackets 4 and 7 are attached to the front walls 11a and 11a of the mounting brackets 11 and 11 which are fixed to the frame 10 extending in the vehicle width direction by spot welding or the like. Positioned, U-shaped clamps 9 and 9 are fitted on the bush 8 of the bush 8 and fixed to the front wall 11a by bolts.

[Problems to be solved by the invention]

By the way, the conventional mounting structure of the rack gear case 1 has the following problems.

Since the case brackets 4 and 7 have a structure in which the flat bottom surface extending in the height direction (H direction in the drawing) is brought into contact with the front wall 11a of the mounting bracket 11 and the upper and lower two positions are fixed, the H direction Although the mounting rigidity of is not so problematic, it is easy to shift with respect to the external force in the vehicle width direction (W direction in the drawing),
The mounting rigidity in the W direction is low. Also, the above mounting bracket
Regarding the rigidity of 11 itself, due to its structure, the rigidity in the vehicle width direction W is low, and improvement of these rigidity is required. Here, in order to improve the mounting rigidity in the vehicle width direction, for example, as proposed in Japanese Utility Model Laid-Open No. Sho 62-90883,
A method of fixing the case brackets 4 and 7 with a connecting bar can be considered. However, in this case, since the number of parts increases, there arises a problem that the cost increases.

An object of the present invention is to provide a rack gear case mounting structure for a steering device which can improve the mounting rigidity of the case bracket and the rigidity of the mounting bracket itself at low cost without increasing the number of parts.

[Means for solving problems]

Therefore, in the present invention, in a structure in which a rack gear case is mounted on a vehicle body via a mounting bracket, the mounting bracket has a cross section composed of a front wall with which the rack gear case abuts and left and right side walls located on both sides of the front wall. The rack is formed in a substantially U shape in a plan view, and the left and right walls are provided with a bead portion including a recessed portion located at the center in the vertical direction and a vehicle width direction bulging portion located above and below the recessed portion. The gear case is characterized in that a pair of flange portions are formed on the outer periphery of the gear case, and the flange portions are locked in the recesses in the vehicle width direction and the vertical direction.

[Action]

According to the rack gear case mounting structure of the present invention,
The rack gear case is formed with flanges that engage with the recesses formed on both side walls of the mounting bracket, so that the flange engages with the mounting bracket against external force in the vehicle width direction and vertical direction to prevent displacement. Therefore, the mounting rigidity can be improved as compared with the conventional structure in which the plate is simply brought into contact with a flat surface. Further, since the recesses for engaging the flange portions are formed on both side walls of the mounting bracket and the bulging portions in the vehicle width direction are formed above and below the recessed portions, the rigidity of the bracket itself can be improved, which in turn improves the rigidity of the entire rack gear case. Therefore, the above-mentioned request can be met.

Further, the mounting bracket of the present invention can be easily formed by press working in the same process as the conventional one, so that the number of parts is not increased and the cost is hardly increased.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 are views for explaining a rack gear case mounting structure according to an embodiment of the present invention, in which the same reference numerals as those in FIG. 5 denote the same or corresponding parts.

As shown in the figure, a rack gear case 1 of this embodiment includes a gear box 3 for accommodating a pinion portion connected to a lower end of a steering shaft 2, a case bracket 20 integrally formed with the box 3, and a vehicle width direction. It is composed of a rack tube 6 for accommodating a rack shaft 5 extending to the inside, and a case bracket 21 mounted in the middle of the tube 6, and its basic structure is substantially the same as the conventional one.

The case brackets 20 and 21 have a semicircular shape when viewed in the axial direction, the bottom surfaces 20b and 21b of each case are formed flat, and the flange portions 20a and 21a are formed over the entire circumference of both side surfaces.
Are integrally formed. That is, the flange portion 20 of the present embodiment
The a and 21a are also formed on the bottom surfaces 20b and 21b of the case brackets 20 and 21, and project from the bottom surfaces 20b and 21b.

Further, the mounting brackets 22 and 22 of the present embodiment are fixed by spot welding to the box-shaped frame 10 having a closed cross section extending in the vehicle width direction, and the bolt insertion holes 23 are provided above and below each front wall 22a. Has been formed. Further, on both side walls 22b of the mounting bracket 22, a bead portion 24 is formed in which the central portion of the side wall 22b is recessed inward and the upper and lower portions thereof are swollen outward. In the assembled state, the bead portion 24 is locked to the flange portions 20a and 21a, and regulates the movement of the case brackets 20 and 21 in the vehicle width direction and the vertical direction.

Next, the function and effect of this embodiment will be described.

In the mounting structure of the present embodiment, in order to mount the rack gear case 1 on the vehicle body, the case brackets 20 and 21 are mounted on the mounting brackets 22 and 22, and the flange portions 20a and 21a thereof are locked to the beat portions 24 and 24. The case brackets 20 and 21, the U-shaped clamps 9 and 9 are fitted between the flange portions 20a, 20a, 21a and 21a of the case brackets 20 and 21 so as to cover the bush 8, and the clamps 9 are fixed by bolts 26. It is fixed to the mounting bracket 22.

As described above, in this embodiment, the flange portions 20a and 21a are formed on the entire circumferences of both end surfaces of the case brackets 20 and 21, and
A concave bead portion 24 is formed in the central portion of both side walls 22b of the mounting bracket 22, and each of the flange portions 20a,
Since 21a is locked, movement of the case brackets 20 and 21 in the horizontal and vertical directions can be regulated, and the rigidity of the mounting bracket 22 itself can be improved. It is possible to improve the mounting rigidity of the rack gear case 1 in the vehicle width direction as compared with the structure in which the abutment is made.

Further, the mounting bracket 22 of the present embodiment can be easily formed by press working, and the flange portions 20a, 21a of the case brackets 20, 21 can also be easily formed by, for example, casting, thus increasing the number of parts. Also, the cost increase can be suppressed.

Furthermore, in the present embodiment, the brackets 20 and 21 can be positioned simply by attaching the flange portions 20a and 21a of the case brackets 20 and 21 to the bead portion 24, and the workability can be improved accordingly.

In the above embodiment, the case where the flange portions 20a and 21a are formed on the case brackets 20 and 21 has been described as an example. However, the present invention forms the flange portion on the outer circumference of the rack tube 6 and attaches it to the bead portion. You may stop it.

FIG. 4 shows a modification of the above embodiment, which is an example in which the left and right mounting brackets are integrally formed. Also in the case of this mounting bracket 30, each flange portion is locked to the central portion of the side wall. By forming the bead portion 31, the same effect as that of the above embodiment can be obtained. Further, in this case, the rigidity of the frame can be further improved, and the number of parts and the number of man-hours for mounting the bracket on the vehicle body can be reduced because they are integrally formed.

[Effect of device]

According to the rack gear case mounting structure for a steering device according to the present invention, a beat portion including a concave portion which is concave in the vehicle width direction and a vehicle width direction bulging portion is formed on both sides of the mounting bracket, and the rack gear case is formed in the bead portion. Since the flange portion is locked, there is an effect that the mounting rigidity of the rack gear case can be improved without increasing the number of parts.

[Brief description of drawings]

1 to 3 are views for explaining a rack gear case mounting structure according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view thereof, FIG. 2 is a partial sectional side view thereof, FIG. 3 is a sectional view taken along the line III-III of FIG. 2, and FIGS. 4 (a) and 4 (b) are mounting brackets, respectively. A perspective view, a plan view, FIG. 5 and FIG. 6 showing a modification of the above are an exploded perspective view and a sectional view showing a conventional mounting structure, respectively. In the figure, 1 is a rack gear case, 10 is a frame (vehicle body), 20 and 21 are case brackets (rack gear case), 20a and 21a are flange portions, 22 and 30 are mounting brackets,
22b is a side wall, and 24 and 31 are bead portions.

Claims (1)

[Scope of utility model registration request] 1. A rack gear case mounting structure for a steering device, wherein a rack gear case extending in the vehicle width direction is mounted on a vehicle body via a mounting bracket. A front wall against which the rack gear case abuts the mounting bracket, and a vehicle on the front wall. The left and right side walls, which are located on both sides in the width direction, have a substantially U-shaped cross section in a plan view, and the left and right side walls have a concave portion in the vehicle width direction located at the center in the vertical direction and the upper and lower sides of the concave portion. And a pair of flange portions are formed on the outer periphery of the rack gear case, and the flange portions are engaged with the recesses of the mounting bracket in the vehicle width direction and the vertical direction. Rack gear case mounting structure for steering device characterized by being stopped.