KR102406077B1 - Coupled Torsion Beam Axle for vehicle - Google Patents

Abstract

The present invention relates to a CTBA of a vehicle capable of increasing turning stability by inducing toe-in of the vehicle when the vehicle is turning.
The CTBA of the vehicle according to the present invention includes a torsion beam 11 provided in the width direction of the vehicle, and a trail provided at both ends of the torsion beam 11 in the front-rear direction of the vehicle, and rear wheels RW are mounted at the rear end. In the CTBA of a vehicle including a ring arm (12) and a trailing arm bush (15) mounted on the front end of the trailing arm (12), when the rear wheel (RW) is bumped or rebounded, the trailing arm (12) is mounted on the vehicle. It is characterized in that it comprises a posture control means for moving in the front-rear direction.

Description

{Coupled Torsion Beam Axle for vehicle}

The present invention relates to a CTBA (Coupled Torsion Beam Axle), which is one of the rear wheel suspensions of a vehicle, and more particularly, to a CTBA of a vehicle capable of increasing turning stability by inducing a toe-in of the vehicle when the vehicle is turning. .

Recently, as one of the vehicle's suspension devices, the CTBA (coupled torsion beam axle) is being applied as a rear wheel suspension that has a simple structure compared to other suspensions, requires fewer parts, and is lightweight.

The approximate configuration of the CTBA is, as shown in FIG. 1 , a torsion beam 11 provided in the width direction of the vehicle, a trailing arm 12 provided at both ends of the torsion beam 11, and the trail It includes a wheel mount bracket 13 on which the rear wheel RW is mounted at the end of the ring arm 12 , and a spring seat 14 on which the spring is seated.

As shown in detail in FIG. 2 , in the CTBA 10 , a trailing arm bush 15 is inserted between the brackets 17 on the vehicle body side installed at the tip of the trailing arm 12 in the CTBA 10 .

The CTBA 10 of the vehicle reduces the impact transmitted through the wheel while the rear wheel RW of the vehicle passes through the unevenness of the road surface or when the vehicle turns, bumps or rebounds.

On the other hand, in the CTBA of a vehicle according to the prior art, the trailing arm 12 and the trailing arm bush 15 are installed to be tilted. As (15) is deformed, wear occurs. In particular, as shown in FIG. 3 , the phenomenon of contact with the bracket 17 is repeated while the trailing arm bush 15 is deformed when a bump occurs, and thus a specific portion of the trailing arm bush 15 is worn. concentration occurs. That is, it can be seen that the portion indicated by A, which is the upper front portion of the vehicle in FIG. 4 , is more severely damaged than the normal portion B. If abrasion is concentrated on a portion of the trailing arm bush 15 , the CTBA may not fully exhibit its function while the vehicle is running.

In addition, the vehicle to which the CTBA 10 is applied does not have a wheel alignment function, and there is a limit to alignment induction due to the behavior of the CTBA 10 according to driving conditions, so there is a fear that steering stability when turning of the vehicle is lowered.

The following prior art document relates to 'structure of a dual characteristic trailing arm bush', and discloses a technology related to a structure of a dual characteristic trailing arm bush for simultaneously improving ride comfort and durability of the bush.

KR 10-2008-0024739 A

The present invention was invented to solve the above problems, and an object of the present invention is to provide a CTBA of a vehicle capable of increasing turning stability by inducing understeer of the vehicle when turning the vehicle.

The CTBA of a vehicle according to the present invention for achieving the above object is a torsion beam provided in the width direction of the vehicle, and a trailing arm provided at both ends of the torsion beam in the front and rear directions of the vehicle, respectively, and a rear wheel is mounted at the rear end and a trailing arm bush mounted on the front end of the trailing arm, wherein the CTBA includes posture control means for moving the trailing arm in the front-rear direction of the vehicle when the rear wheel bumps or rebounds. .

The posture control means moves the trailing arm toward the front of the vehicle when the rear wheel is bumped, and moves the trailing arm toward the rear of the vehicle when the rear wheel rebounds.

The posture control means includes a fixing block installed on the trailing arm, and a shaft screwed to the fixing block and engaged with a fixing shaft of the trailing arm bush that passes through the trailing arm bush and is fixed to the vehicle body. do.

When the fixing block and the shaft rotate in a direction in which the rear end of the trailing arm is upwardly rotated about the fixing shaft of the trailing arm bush, the shaft is screwed to move the fixing block toward the front of the vehicle. .

A bevel gear is installed in the middle of the fixing shaft of the trailing arm bush and a front end of the shaft, and the bevel gear is meshed with each other.

The shaft is divided into two in the middle part, characterized in that it is connected to each other by a universal joint.

The posture control means includes a fixing part disposed in the longitudinal direction of the trailing arm and having a rear end fixed to one side of the trailing arm, the front end of the fixing part and the outer cylinder are fastened, and disposed in a direction perpendicular to the fixing part It further includes an auxiliary bushing, wherein both ends of the fixing block are connected to both ends of the fixing shaft of the auxiliary bushes installed to pass through the auxiliary bushes by fixing rods.

The CTBA of the vehicle according to the present invention having the above configuration is controlled so as to be toe-in by itself when the vehicle turns or when bumping/rebounding, so that steering stability is improved.

In addition, it is possible to prevent uneven wear of the trailing arm bush installed between the CTBA and the vehicle body, so that the CTBA can fully exhibit its function even when durability is advanced.

1 is a plan view showing the structure of a CTBA of a conventional vehicle.
2 is a plan view showing an enlarged end of the trailing arm in the CTBA of the vehicle according to the prior art.
3 is a plan view illustrating a principle in which wear occurs at an end of a trailing arm in a CTBA of a vehicle according to the prior art;
Figure 4 is a photograph of a state in which wear occurs at the end of the trailing arm in the CTBA of the vehicle according to the prior art.
5 is a plan view showing the main part of the CTBA of the vehicle according to the present invention.
6 is a side view showing a main part of a CTBA of a vehicle according to the present invention;
7 is a side view showing the state of the right rear wheel when the CTBA of the vehicle according to the present invention makes a left turn of the vehicle.
8 is a side view showing the state of the left rear wheel when the CTBA of the vehicle according to the present invention turns left of the vehicle.
9 is a plan view illustrating a state in which understeer is induced when turning by a CTBA of a vehicle according to the present invention.

Hereinafter, a CTBA of a vehicle according to the present invention will be described in detail with reference to the accompanying drawings.

The CTBA of the vehicle according to the present invention includes an attitude control means capable of controlling the attitude of the CTBA 10 when the vehicle turns or passes through irregularities in the conventional CTBA 10 .

The CTBA 10 includes a torsion beam 11 installed in the width direction of the vehicle, a trailing arm 12 disposed in the longitudinal direction of the vehicle and fastened to both ends of the torsion beam 11 , and the trailing arm 12 . ), a trailing arm bush (15) interposed in a portion where the front end of the vehicle body is fastened, a wheel mount bracket (13) installed behind the trailing arm bush (15) to which a rear wheel (RW) is installed, and the trailing arm; and a spring seat 14 for supporting a spring installed between the vehicle body.

At this time, the trailing arm bush fixing shaft 16 passing through the trailing arm bush 15 passes through the trailing arm bush 15 and the bracket 17 installed at the tip of the trailing arm 12 and one side of the vehicle body. Thus, the front end of the trailing arm 12 is fixed to the vehicle body, thereby preventing transmission of an impact from the road surface.

In addition, the trailing arm bush 15 is fastened to the tip of the trailing arm 12 in a tilted state by a predetermined angle.

The posture control means improves the steering stability of the CTBA 10 by making the trailing arm 12 minutely move in the front-rear direction of the vehicle when the vehicle turns or when the rear wheel RW is bumped/rebounded.

When the rear end of the trailing arm 12 rotates about the trailing arm bush fixing shaft 16 as the center, the posture control means converts it into a linear motion, thereby controlling the posture of the CTBA 10, To improve steering stability.

Here, when the posture control means rotates in a direction in which the rear end of the trailing arm 12 rises around the fixing shaft 16 of the trailing arm bush to which the front end of the trailing arm 12 is fixed, the trailing arm 12 ) to the front of the vehicle, and when the trailing end of the trailing rotates in the descending direction, the trailing arm 12 is minutely moved to the rear of the vehicle, thereby controlling the posture of the CTBA 10. .

A detailed configuration of the posture control means shown in FIGS. 5 and 6 is as follows.

The fixing part 21 is arranged in the longitudinal direction of the trailing arm 12 , and a rear end thereof is fixed to one side of the trailing arm 12 , preferably to an end of the trailing arm 12 . The fixing part 21 is fixed to the trailing arm 12 by welding, bolts, or the like.

The auxiliary bushing 22 is disposed in a direction perpendicular to the trailing arm 12 , that is, in a direction perpendicular to the fixing part 21 . An outer cylinder of the auxiliary bushing 22 is fastened to the front end of the fixing part 21 of the auxiliary bushing 22 . An auxiliary bushing fixing shaft 22a may be installed to pass through the auxiliary bushing 22 . The auxiliary bushing 22 is formed in a structure of an outer housing-rubber-inner housing which is a general structure of a bush. The auxiliary bushing 22 absorbs the shock generated between the fixing part 21 and the fixing block 23 to be described later. By the rubber of the auxiliary bushing 21, an external shock is prevented from being transmitted to the vehicle body between the fixing part 21 and the fixing block 23 made of a metal material. In this case, the auxiliary bush 22 should have the same or greater modulus of elasticity than the trailing arm bush 15 . The reason is to more efficiently induce the deformation of the trailing arm bush 15 .

The fixing block 23 is positioned to be spaced apart from the auxiliary bushing 22 from the auxiliary bushing 22 to the side where the trailing arm 12 is located. The fixing block 23 is disposed in a direction parallel to the auxiliary bush 22 . Both ends of the fixing block 23 are installed to be connected to both ends of the auxiliary bushing fixing shaft 22a, respectively.

In addition, a through hole is formed in the fixing block 23 to penetrate the fixing block 23 in the longitudinal direction of the trailing arm 12 , and a thread is formed in the through hole.

The shaft 24 is disposed in the longitudinal direction of the trailing arm 12 and is screwed to the fixing block 23 . A portion of the shaft 24 is installed to pass through the fixing block 23 so that the shaft 24 has a fixed position. A screw portion 24b processed with a screw thread is formed on the outer surface of the portion where the shaft 24 passes through the fixing block 23 , and is screwed with the screw thread formed in the fixing block 23 . Since the shaft 24 and the fixing block 23 are screwed together, when the trailing arm 12 rotates in the circumferential direction of the shaft 24 when the vehicle turns or when bumping/rebounding, the trailing arm 12 ) to move slightly in the front-rear direction of the vehicle.

The front end of the shaft 24 is meshed with the trailing arm bush fixing shaft 16 . Bevel gears 25 and 26 are installed in the middle of the trailing arm bush fixing shaft 16 and at the front end of the shaft 24, respectively, and are meshed with each other.

The shaft 24 is divided in two in the middle, and is connected to each other by a universal joint 24a. The front end of the shaft 24 is connected to the trailing arm bush 15, and the rear of the shaft 24 is connected to the trailing arm 12. The trailing arm bush 15 and the trailing arm 12 ) is installed in a tilted state. In addition, this is to respond to the relative motion of the outer cylinder of the trailing arm bush 15 due to the deformation of the trailing arm bush 15 .

The operation of the CTBA of the vehicle according to the present invention having the above configuration will be described.

7 shows the action of the right rear wheel RW when bumping. Fig. 7 (a) shows a normal state, and Fig. 7 (b) shows a state when the right rear wheel RW is bumped. When the right rear wheel RW bumps, the right rear wheel RW, which becomes the outer wheel when the vehicle turns left, may be bumped by a greater centrifugal force than the inner wheel (left rear wheel), and the right rear wheel RW is When passing through a protruding part from the road surface, it may be bumped.

When the right rear wheel RW is bumped, the trailing arm 12 rotates in a direction in which the rear end rises centering on the front end fixed to the vehicle body (refer to arrow A in FIG. 7(b) ). Since the rear wheel RW in the trailing arm 12 is mounted adjacent to the rear end, when the right rear wheel RW bumps, the rear end of the trailing arm 12 rises.

When the trailing arm 12 rises, the shaft 24 also rotates together with the trailing arm 12 . Since the trailing arm bush fixing shaft 16 is fixed to the vehicle body, the shaft 24 rotates about the trailing arm bush fixing shaft 16 so that the rear end rises, and the bevel gears 25 and 26 ) are meshed with each other, so that the shaft 24 rotates in the circumferential direction of the shaft 24 .

When the shaft 24 rotates in the circumferential direction of the shaft 24, the fixing block 23 moves slightly toward the front of the vehicle. It moves slightly toward the front of the vehicle (direction A' in Fig. 7 (b)). When the shaft 24 and the fixing block 23 rotate in a direction in which the rear end of the trailing arm 12 is upward, the shaft 24 moves the fixing block 23 toward the front of the vehicle. Since they are coupled, the fixing block 23 and the trailing arm 12 move slightly toward the front of the vehicle.

Meanwhile, FIG. 8 shows a state when the left rear wheel RW of the vehicle rebounds. Fig. 8(a) shows the normal state of the left rear wheel RW, and Fig. 8(b) shows the state when the left rear wheel RW rebounds. The case where the left rear wheel RW rebounds is when the vehicle turns left or when the left rear wheel RW passes through a groove in the road surface.

When the left rear wheel RW rebounds, the reverse action of FIG. 7(b) occurs, so that the trailing arm 12 on which the left rear wheel RW is installed micro-moves to the rear of the vehicle. That is, when the left rear wheel RW rebounds, the rear end of the trailing arm 12 descends (direction B in FIG. The fixing block 23 rotates in the circumferential direction of the shaft 24 in a direction to move to the rear of the vehicle.

As the shaft 24 rotates in the circumferential direction, the fixing block 23 and the trailing arm 12 move together in the rear direction of the vehicle (direction B' in FIG. 8(b)).

Accordingly, when the vehicle turns left, as shown in FIG. 9 , understeer is induced. That is, when the vehicle turns to the left, bumping of the outer wheel (the right wheel in Fig. 9) is larger than that of the inner wheel (the left wheel in Fig. 9) due to the centrifugal force. Accordingly, as shown in FIG. 9 , in the outer ring in which bumping occurs significantly, as the trailing arm bush 15 moves forward more than in the inner ring, the CTBA of the vehicle behaves as shown in the lower right corner of FIG. 9 , resulting in understeer is induced

Meanwhile, when the vehicle turns right, the posture of the CTBA 10 is controlled in the opposite direction to that of FIG. 9 .

In this way, since understeer is induced during turning, steering stability during turning is improved.

10: CTBA 11: torsion beam
12: trailing arm 13: wheel mount
14: spring seat 15: trailing arm bush
16: trailing arm bush fixed shaft 17: bracket
21: fixed part 22: auxiliary bush
22a: auxiliary bush fixed shaft 23: fixed block
23a: fixed rod 24: shaft
24a: universal joint 24b: screw part
25, 26: bevel gear 24b: screw part

Claims (7)

A vehicle comprising: a torsion beam provided in the width direction of the vehicle; a trailing arm provided at both ends of the torsion beam in the front-rear direction of the vehicle, respectively, and a rear wheel mounted on the rear end; and a trailing arm bush mounted on the front end of the trailing arm In the CTBA (coupled torsion beam axle) of
and posture control means for moving the trailing arm in the front-rear direction of the vehicle when the rear wheel bumps or rebounds;
The posture control means,
a fixing block installed on the trailing arm;
and a shaft screwed to the fixing block and engaged with a fixing shaft of the trailing arm bush that passes through the trailing arm bush and is fixed to the vehicle body. According to claim 1,
The posture control means,
When the rear wheel bumps, the trailing arm moves toward the front of the vehicle,
The CTBA of a vehicle, characterized in that when the rear wheel rebounds, the trailing arm moves toward the rear of the vehicle. delete According to claim 1,
The fixed block and the shaft,
When the rear end of the trailing arm rotates in an upward direction around the fixing shaft of the trailing arm bush, the shaft is screwed to move the fixing block toward the front of the vehicle. According to claim 1,
A CTBA of a vehicle, characterized in that a bevel gear is installed in the middle of the fixed shaft of the trailing arm bush and a front end of the shaft, and the bevel gear is meshed with each other. According to claim 1,
The shaft is divided into two in the middle portion, CTBA of a vehicle, characterized in that connected to each other by a universal joint. According to claim 1,
The posture control means,
a fixing part disposed in the longitudinal direction of the trailing arm and having a rear end fixed to one side of the trailing arm;
The front end of the fixing part and the outer cylinder are fastened, and further comprising an auxiliary bush disposed in a direction perpendicular to the fixing part,
Both ends of the fixing block are connected to both ends of the fixing shaft of the auxiliary bush installed to pass through the auxiliary bush by means of a fixed rod.

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