KR101337963B1 - Bush for subframe of vehicle - Google Patents

Abstract

The present invention relates to a shock absorbing device of a subframe for a vehicle, which can secure a crash deformation space because a subframe is separated from a car body and descends during a car crash by improving a bush structure mounted on a car body joint of the subframe. A bush structure which combines the front end of a subframe of a vehicle and a car body comprises an upper outer pipe kept to be combined with the car body, and a lower outer pipe which is separated by shock during a car crash. Because the lower outer pipe is separated by shock during a crash along with the subframe, the subframe is moved back and, at the same time and induces shock buffering of lagging downward during a crash in order to significantly reduce the degree of injury of a pedestrian and a passenger.

Description

Collision shock absorber of vehicle subframe {Bush for subframe of vehicle}

The present invention relates to a shock absorber of a vehicle subframe, and more particularly, to improve the bush structure mounted on the body coupling portion of the subframe, to ensure that the collision deformation space is lowered while the subframe is separated from the vehicle body in the event of a vehicle crash accident To a collision buffer of a vehicle subframe.

As is well known, the skeleton of a vehicle is largely composed of a body and a chassis, and one of the components of the vehicle body has a sub-frame in which each corner portion is located at the bottom of the vehicle body. Combined into multiple parts on the right side member and cross member, it supports the main parts such as engine and transmission that are mounted in the engine room.

More specifically, the engine is mounted on the front, rear, and both sides of the subframe via a damping function, and a row member for supporting a radiator is disposed at the front end of the subframe, and at the rear end of the subframe. A dash panel is arranged to distinguish the engine room from the interior.

Here, the subframe is described with reference to FIGS. 3 and 4 attached to the structure coupled to the vehicle body by the bush as follows.

In order to couple the subframe 10 to the vehicle body thereon, the bush indentation cup 12 having a constant inner diameter space is integrally mounted at four corners of the subframe 10, and the bush indentation cup 12 is integrally mounted. By inserting the bush 20 into the vehicle body, the bush 20 is inserted into the vehicle body, thereby coupling the subframe 10 to the vehicle body.

The bush 20 is composed of an inner pipe 22 and an outer pipe 26 spaced apart from each other, and a vibration absorbing tube 24 disposed between the inner pipe 22 and the outer pipe 26, the upper portion of the sub The upper stopper 27 is integrally formed on the upper surface of the outer circumference of the frame 10, and the lower stopper 28 is integrally connected to the lower ends of the outer and inner pipes.

Therefore, the bolt 30 is inserted through the inner diameter portion of the inner pipe 22 of the bush 20, while the head of the bolt 30 is in close contact with the bottom of the lower stopper 28, and at the same time, By inserting and fastening the screw portion to the vehicle body, a firm coupling of the subframe 10 to the vehicle body is achieved.

However, since the subframe 10 is firmly assembled to the vehicle body by the bush 20 during the crash, only the front end portion of the subframe is contracted by the impact, and the subframe does not have any shock absorbing function. It is one of the factors that increases passenger injury.

Therefore, the subframe serves as a skeleton in which a large number of components are mounted, including main components such as an engine and a transmission, but should be designed to maintain overall rigidity and durability. It is to be designed to prevent the injury of the occupants.

Nevertheless, there is an increasing demand for compact engine room packages to improve passenger occupancy through increased vehicle interior space, thereby reducing the gap between the bodywork, engine and suspension subframes, which causes This leads to a reduction in deformation space for shock absorption, thereby increasing passenger injury, leading to a problem of deterioration of collision performance.

Therefore, the subframe is normally firmly coupled to the vehicle body, and in the event of a collision, there is a demand for a method of reducing passenger injury through appropriate deformation or damage.

The present invention has been made in view of the above, and improved the bush structure that combines the front end of the vehicle subframe and the vehicle body to a structure that can be separated by the impact in the event of a collision, and at the same time the subframe is pushed back during the vehicle collision It is an object of the present invention to provide a collision shock absorber of a vehicle subframe that can easily secure a deformation space for absorbing shock during a collision by inducing downward movement.

The present invention for achieving the above object is: to couple the subframe with the vehicle body, the inner and outer pipes spaced apart from each other, and the vibration absorbing tube disposed between the inner and outer pipes, and through the inner pipe to the body In the collision buffer device of a vehicle subframe including a bolt that is inserted and fastened, the outer pipe is composed of an upper outer pipe and a lower outer pipe pressed into the inner diameter of the bush indentation cup of the subframe, the upper outer pipe in the event of a vehicle crash Is coupled to the vehicle body together with the inner pipe and the vibration absorbing tube, and the lower outer pipe is separated from the upper outer pipe and pushed back together with the subframe so as to move downward. .

In particular, the upper end of the upper outer pipe is press-fitted into the upper inner diameter of the bush press-fit cup, characterized in that the lower outer pipe receiving step space is formed on the outer diameter surface of the lower end of the upper outer pipe as much as the thickness of the lower outer pipe.

In addition, a lower stopper is integrally formed at the lower end of the lower outer pipe, so that the inner circumferential end of the lower stopper is fitted between the lower end of the inner pipe and the head of the bolt.

Through the above-mentioned means for solving the problems, the present invention provides the following effects.

According to the present invention, the bush structure for coupling between the front end of the subframe of the vehicle and the vehicle body is composed of an upper outer pipe that is held and coupled with the vehicle body, and a lower outer pipe that is separated by an impact during a crash, By allowing the outer pipe to be separated together with the subframe, it is possible to greatly reduce the injury of pedestrians and passengers by inducing shock buffers that push the subframe backwards and sag downwards in the event of a collision.

1 is a cross-sectional view showing a collision buffer of a vehicle subframe according to the present invention,
2 is a cross-sectional view illustrating the operational flow of the collision buffer of the vehicle subframe according to the present invention;
3 is a cross-sectional view showing a conventional bush structure,
4 is a schematic diagram illustrating a bush mounting position of a subframe.

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

According to the present invention, the subframe supporting parts such as the engine and the transmission are pushed backward and moved downward while being separated from the vehicle body, thereby ensuring a buffer space for pedestrians and providing shock buffering power to pedestrians and passengers. The focus is on providing more and reducing injuries.

Referring to FIG. 2, as a means for coupling the subframe 10 to a vehicle body above it, the subframe 10 is press-fitted in the bush press-fit cup 12 having a constant inner diameter space at four corners of the subframe 10. And a bush 30.

At this time, the bush 20 is composed of a vibration absorbing tube 24 disposed between the inner pipe 22 and the outer pipe 26 and the inner pipe 22 and the outer pipe 26 spaced apart from each other, The outer pipe 26 is in direct contact with the inner diameter of the bush press-fit cup 12 of the subframe 10 and becomes a press-fitted portion, and the bolt 30 is inserted through the inner diameter of the inner pipe 22.

Accordingly, while the bush 20 is pressed into the bush press-fit cup 12 of the subframe 10 as described above, the bolt 30 is inserted through the inner diameter of the inner pipe 22, but the bolt 30 By inserting and fastening the screw portion to the vehicle body, the subframe 10 is coupled to the vehicle body.

Bush 20 according to the present invention, as shown in Figure 1 and 2 attached, the outer pipe 26 is provided with a two-piece structure that can be separated from each other, such as the upper outer pipe (26a) and the lower outer pipe (26b) It is characterized by one point, the upper outer pipe (26a) and the lower outer pipe (26b) that can be separated up and down are press-fitted to the inner diameter of the bush indentation cup 12 of the subframe 10 at the same time, by impact in the event of impact It is fastened in a structure that is separated from each other.

More specifically, the outer pipe 26 of the bush 20 is composed of an upper outer pipe 26a and a lower outer pipe 26b that can be separated up and down, and the upper end of the upper outer pipe 26a has a bush indentation cup. The lower outer pipe 26b is pressed into the lower inner diameter portion of the bush indentation cup 12 while being pressed into the upper inner diameter portion of the upper portion 12.

In particular, the receiving step space 29 is formed on the outer diameter surface of the lower end of the upper outer pipe 26a of the outer pipe 26 so that the lower outer pipe 26b can be inserted and seated, and the receiving step space 29 ) Is formed to be equal to the thickness of the lower outer pipe (26b).

Therefore, when the lower outer pipe 26b is pressed into the lower inner diameter portion of the bush press-fit cup 12, the outer diameter surface of the lower outer pipe 26b is in close contact with the lower inner diameter portion of the bush press-in cup 12. The inner diameter surface of the lower outer pipe 26b comes into close contact with the outer diameter of the accommodation step space 29.

Accordingly, in order to couple the subframe to the vehicle body, the bolt 30 is inserted through the inner diameter portion of the inner pipe 22 of the bush 20, and the head of the bolt 30 has a bottom surface of the lower stopper 28. By tightly inserting and fastening the threaded portion of the bolt 30 to the vehicle body, a rigid coupling of the subframe 10 to the vehicle body is achieved.

Meanwhile, the lower stopper 28 is integrally formed at the lower end of the lower outer pipe 26b, and the inner circumferential end of the lower stopper 28 is between the lower end of the inner pipe 22 and the head of the bolt 30. The upper surface of the inner circumferential end of the lower stopper 28 supports the inner pipe 22, and the head of the bolt 30 is in close contact with the bottom surface.

As such, the outer pipe 26 press-fitted into the bush press-fit cup 12 of the subframe 10, that is, the upper and lower outer pipes 26a and 26b is press-assembled, and the release force is 4,000 under normal use conditions. Since the level is ˜5,000 kgf, the subframe 10 may be firmly fixed to the vehicle body.

In addition, the upper and lower loads applied to the subframe 10 and the bush 20 during the frontal collision are 10,000 kgf or more, which is a level at which the lower outer pipe 26b is sufficiently separated from the upper outer pipe 26a. 10 can be easily separated from the vehicle body together with the lower outer pipe 26b.

Here, the operation flow for the collision buffer of the vehicle subframe of the present invention having the above structure will be described with reference to FIG. 2.

In the frontal collision of the vehicle, impact loads are simultaneously applied in the front direction and the up direction of the subframe, and a heavy load of about 10,000 kgf is applied in the vertical direction.

Therefore, the subframe 10 is pushed backwards, and the subframe 10 is separated from the vehicle body by the up and down impact, and moved downward, thereby providing a shock absorbing function while providing a shock buffer space.

More specifically, due to the impact in the event of a vehicle crash, the lower outer pipe 26b is separated from the upper outer pipe 26a and pushed backward together with the subframe 10 and moved downward, and the upper outer pipe 26a. ) Is in a state of being continuously coupled to the vehicle body together with the inner pipe 22 and the vibration absorbing tube 24.

As described above, according to the present invention, the lower outer pipe 26b is separated from the vehicle body together with the subframe 10 due to the impact at the time of collision, and the subframe is pushed backward and sag downwards, thereby providing a shock buffer space for the pedestrian. Shock absorbing function can be provided while the injury of pedestrians and passengers can be greatly reduced.

10: subframe
12: bush indentation cup
20: bush
22: inner pipe
24: vibration absorption tube
26: outer pipe
26a: Upper outer pipe
26b: lower outer pipe
27: upper stopper
28: lower stopper
29: lower outer pipe receiving step space
30: Bolt

Claims (3)

In order to couple the subframe 10 to the vehicle body, the inner tube 22 and outer pipe 26 spaced apart from each other, and the vibration absorbing tube 24 disposed between the inner pipe 22 and the outer pipe 26 and In the collision buffer of the vehicle subframe comprising a bolt 30 is inserted into the vehicle body through the inner pipe 22,
The outer pipe 26 is composed of an upper outer pipe 26a and a lower outer pipe 26b press-fitted into the inner diameter of the bush press-fit cup 12 of the subframe 10,
In the event of a collision of the vehicle, the upper outer pipe 26a is held and coupled to the vehicle body together with the inner pipe 22 and the vibration absorbing tube 24, and the lower outer pipe 26b is separated from the upper outer pipe 26a and is separated from the subframe ( 10) and the shock absorber of the vehicle subframe characterized in that it is pushed back and moved downward.
The method according to claim 1,
The upper end of the upper outer pipe 26a is press-fitted into the upper inner diameter of the bush press-fit cup 12, and the lower outer pipe accommodating the thickness of the lower outer pipe 26b on the outer diameter surface of the lower end of the upper outer pipe 26a. Collision shock absorber of the vehicle subframe, characterized in that the stepped space 29 is formed.
The method according to claim 1,
The lower stopper 28 is integrally formed at the lower end of the lower outer pipe 26b so that the inner circumferential end of the lower stopper 28 is sandwiched between the lower end of the inner pipe 22 and the head of the bolt 30. Impingement shock absorber of the vehicle subframe, characterized in that.

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