KR20160041484A

KR20160041484A - Structure for mounting steering gear box

Info

Publication number: KR20160041484A
Application number: KR1020140135523A
Authority: KR
Inventors: 이후광
Original assignee: 현대자동차주식회사
Priority date: 2014-10-08
Filing date: 2014-10-08
Publication date: 2016-04-18
Also published as: KR102053467B1

Abstract

The present invention relates to a structure to prevent a steering gear box assembly from being twisted by directly coupling a steering gear box to a cross member. The present invention provides a structure for mounting a steering gear box, which can prevent assembly deformation of a gear box housing as well as reducing a production cost as a rubber bush is eliminated by realizing a new structure of a gear box assembly method to directly coupling or solid mounting a steering gear box using a mounting adapter to enable a left surface height of a gear box to be flat through a mechanical process and a mounting pipe in which the mounting adapter is pressed.

Description

{Structure for mounting steering gear box}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering gearbox mounting structure, and more particularly, to a structure for preventing steering gearbox assembly from twisting by directly fastening a steering gearbox to a cross member.

Generally, a steering apparatus is a device for changing the running direction of an automobile and is composed of a steering wheel, a steering gear box, a pitman arm, a drag link, a tie rod, a steering knuckle, (Power steering).

Such a steering apparatus includes a steering operation mechanism for transmitting the operating force of the driver to the steering gear mechanism, a steering gear mechanism for changing the direction of the steering operation force and transmitting rotational force to the steering link mechanism, And a steering link mechanism that transmits the motion to the front wheel and maintains the left and right front wheels constantly.

Here, the steering gear mechanism includes a steering gear box that houses a rack gear, a pinion gear, and the like, and the steering gear box is installed in a four-point support structure on a vehicle body, that is, a cross member.

For example, as shown in Fig. 4, two gearbox mounting seating surfaces 110a, 110b, 110c, and 110d are formed on the left and right sides of the cross member 100, respectively, and each gearbox mounting seating surface 110a 110b, 110c, 110d of the gearbox housing (not shown), and then fastened by respective stud bolts (not shown).

5, the mounting pipe 120 is installed on the gear box mounting seating surfaces 110a, 110b, 110c, and 110d of the cross member 100 in a welded manner, The stud bolt 140 is directly fastened to the threaded portion 150 of the mounting pipe 120 or is fastened with the rubber bush 160 interposed therebetween so that the steering gear box 4 And can be installed in a point support structure.

However, the front cross member assembled by arc welding is constrained by a strong jig, and the mounting span (left and right 536mm) is fine on the left and right gear box mounting seat surface due to the thermal deformation even when assembled, There is nothing.

This height difference causes bending and torsional deformation in the gearbox housing of the aluminum die casting material when the four-point solid gearbox is tightened, thereby increasing the friction with the rack bushes inside the gearbox housing, thereby deteriorating steering performance.

This phenomenon occurred as field creel in existing mass production vehicles.

In order to solve this height step difference problem, the present gear box mounting structure employs a structure in which two rubber bushes are applied to one side of the right and left sides, and the gear box deformation due to the height difference is replaced with a rubber deformation.

However, the cost increases due to the application of the rubber bush, and the minimum thickness of the gear box housing in which the rubber bush is press-fitted is required. Therefore, the area of the fastening portion is increased (diameter is 10 mm or more).

Techniques underlying the present invention are disclosed in U.S. Patents US5251932, US6149197, US4314710, and the like.

Accordingly, the present invention has been made in consideration of this point, and it is a new structure for mounting the steering gear box directly (solid mounting) using a mounting adapter capable of flattening the height of the gearbox seat surface through machining and a mounting pipe The present invention provides a steering gear box mounting structure capable of preventing a reduction in cost due to the elimination of a rubber bush as well as an assembling deformation of a gearbox housing.

In order to achieve the above object, a steering gear box mounting structure according to the present invention has the following features.

The steering gear box mounting structure has a structure in which a gear box housing is mounted on a seating surface provided on a cross member, a mounting pipe is installed on an inner seating surface of the cross member, and an upper surface of the mounting seat is coupled to an upper end of the mounting pipe And a stud bolt passing through the bolt fastening portion and the mounting adapter is fastened to the threaded portion of the mounting pipe while the bolt fastening portion of the gear box housing is positioned on the upper surface of the mounting adapter.

Here, the mounting adapter may be coupled to the mounting pipe in a structure in which the mounting adapter is press-fitted into the adapter groove at the upper end of the mounting pipe.

The mounting adapter may be made of the same aluminum material as the gear box housing material.

As a preferred embodiment, the mounting adapter mounted on each seating surface of the cross member can be made to have the same height at the left and right sides of the upper end of each mounting adapter through upper machining.

In a preferred embodiment, the mounting adapter mounted on the mounting seat and coupled to the mounting pipe may be subjected to an electrodeposition coating process prior to machining to planarize the seat surface height.

The steering gear box mounting structure provided by the present invention has the following advantages.

First, the cost can be saved by eliminating the rubber bush.

The mounting space of the mounting adapter made of the same material as the gearbox housing is the same as the space of the gear box housing of the existing solid mounting condition, so there is no additional material cost.

However, machining cost is increased by machining the upper part of the mounting adapter before assembling the gear box, but the roughing of the aluminum material with low strength is sufficient, so the machining speed is fast and the increase of the machining cost is small.

Secondly, since the assembly of the gear box housing is not deformed at all while applying the solid mounting structure, it is possible to eliminate the deterioration of the merchantability, such as the loss of the steering force due to the steering friction and the deterioration of the steering feeling.

In addition, it is possible to eliminate the possibility of stiffness degradation due to the lateral load which may be deteriorated when applying the bush mount, so that the lateral stiffness of the front wheel can be further increased compared with the rubber bushing specification.

Third, because the rubber bush can be eliminated (the mounting space is the same as the existing solid mounting gearbox), it is advantageous in terms of layout.

In addition, the shape of the crossmember in which the left and right mounting surfaces are formed only in a plane can be freely designed due to the difficulty in flatness management of the left and right side cross members.

In the present invention, since the flatness of the left and right gear box mount seat can be adjusted through machining, it is possible to design a complicated seating surface.

This increases the degree of freedom in designing the shape of the cross member, thereby facilitating layout design.

Fourth, since the electroplating is performed after the mounting adapter is press-fitted, there is no possibility of corrosion of the potential difference due to the use of different materials between the cross member top plate of the steel sheet material and the mounting adapter of the aluminum material.

1 is a perspective view showing a cross member in which a gear box housing is installed in a steering gear box mounting structure according to an embodiment of the present invention;
FIG. 2 is a cross-sectional view showing a gearbox housing assembling state in a steering gear box mounting structure according to an embodiment of the present invention; FIG.
3 is a cross-sectional view illustrating a method of leveling the seating surface height of a gearbox housing in a steering gear box mounting structure according to an embodiment of the present invention.
4 is a perspective view showing a cross member on which the steering gear box is mounted;
5 is a cross-sectional view showing various examples of a mounting structure of a conventional steering gear box

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a cross member in which a gearbox housing is installed in a steering gearbox mounting structure according to an embodiment of the present invention, and FIG. 2 is a perspective view of a gearbox housing in a steering gearbox mounting structure according to an embodiment of the present invention. Sectional view showing an assembled state.

As shown in FIGS. 1 and 2, the steering gear box mounting structure employs a mounting adapter and a planar structure of the gearbox seat surface height, thereby solving the height step difference problem and reducing the cost .

To this end, a total of four mounting seating surfaces 11 are formed in the cross member 10, two on each of the left and right sides, and the gear box housing 13 is fastened with the mounting seating surfaces 11, As shown in FIG.

In the mounting seat 11, the mounting pipe 12 is vertically installed in an arc-welded structure.

At this time, an adapter groove 18 is formed on the upper end surface of the mounting pipe 12 so that the mounting adapter 16 can be coupled thereto. The inner circumferential surface of the mounting pipe 12 is connected to the stud bolt 14 And a threaded portion 15 for fastening the threaded portion 15a.

In particular, a mounting adapter 16 is mounted on the mounting seat 11, which is the place where the bolt fastening portion 17 of the gearbox housing 13 is placed.

At this time, the mounting adapter 16 has an integral structure of the circular boss portion 16a and the flange portion 16b formed at the upper end of the boss portion.

Here, the mounting adapter 16 can be made of the same aluminum material as the gear box housing 13 made of aluminum.

This mounting adapter 16 is installed in a structure to be coupled to the upper end of the mounting pipe 12.

For example, the mounting adapter 16 is installed in the adapter groove 18 formed on the upper surface of the mounting pipe 12 using a boss 16a, The flange portion 16b of the flange portion 16 is placed in a structure in close contact with the mounting seat surface 11. [

Thus, the electrodeposition coating process can be performed in a state where the mounting adapter 16 and the mounting pipe 12 are mounted on the mounting seat surface 11 of the cross member 10.

That is, the electrodeposition coating process is performed on the entire cross member 10 including the mounting adapter 16 before the mounting adapter 16 is subjected to the flattening process after the mounting adapter 16 is press-fitted and fixed .

This is to eliminate the possibility of potential difference erosion due to the use of different materials between the cross member of steel sheet material and the mounting adapter of aluminum material.

On the other hand, in order to eliminate the height difference due to the long span of the left and right sides of the gear box mounting seat surface 11, the height of the gear box seat surface can be flattened.

3, the upper end of each mounting adapter 16 mounted on each mounting seat 11 of the cross member 10 has the same height at the right and left, So that machining can be performed.

For example, after the electrodeposition coating is performed, the upper ends of the four mounting adapters 16 are fixed to the jig (not shown) by machining to an appropriate depth so that the left and right heights are the same, that is, ) To make the height of the left and right sides of the gear box seat the same.

Since the gear box mounting height of the cross member 10 thus machined is completely free from errors in the right and left directions, no deformation due to twisting, bending, or the like occurs at the time of directly fastening the gear box.

In order to substantially mount the gearbox housing 13, the threaded fastening portion 17 of the gearbox housing 13, with the upper end of each mounting adapter 16 being flattened by machining, As shown in FIG.

Since the bolts 17 and the mounting adapter 16 are sequentially passed through the stud bolts 14 and the stud bolts 14 are fastened to the threaded portions 15 of the mounting pipe 12, The installation of the gear box housing by the stud bolt fastening structure is completed.

As described above, the present invention adopts a mounting adapter and a mounting pipe machined to press the mounting adapter, and the mounting adapter improves the height difference between the left and right sides by machining before assembly of the gear box, The rubber mounting method of the gear box and the cross member can be improved by a solid fastening method in which some structures of the gear box are integrated. Therefore, there is an advantage of cost reduction, increase in steering rigidity, prevention of steering feeling deterioration, and layout improvement.

10: Cross member
11: Mounting seat
12: Mounting pipe
13: Gear box housing
14: Stud bolt
15:
16: Mounting adapter
16a: boss part
16b: flange portion
17: bolt fastening portion
18: Adapter home
19: Milling machine

Claims

In the structure in which the gear box housing 13 is mounted on the mounting seat surface 11 provided on the cross member 10,
A mounting pipe 12 is installed inward on the mounting seat 11 of the cross member 10 and a mounting adapter 16 is mounted on the upper surface of the mounting seat 11 to be coupled to the upper end of the mounting pipe 12. And a stud bolt 14 passing through the bolt fastening portion 17 and the mounting adapter 16 in a state where the bolt fastening portion 17 of the gear box housing 13 is positioned on the upper surface of the mounting adapter 16 Is fastened to the threaded portion (15) of the mounting pipe (12).

The method according to claim 1,
Characterized in that the mounting adapter (16) is press-fitted into the adapter groove (18) at the top of the mounting pipe (12) and is coupled to the mounting pipe side.

The method of claim 2,
Wherein the mounting adapter (16) is made of the same aluminum material as the gear box housing material.

The method according to claim 1,
Wherein a mounting adapter (16) mounted on each mounting seat (11) of the cross member (10) has a left and right height at the top of each mounting adapter through upper machining.

The method according to claim 1 or 4,
Wherein the mounting adapter (16) mounted on the mounting seat (11) and coupled to the mounting pipe (12) is subjected to an electrodeposition coating process before machining for leveling the seating surface height.