KR20200060848A - Coupled torsion beam axle for vehicle - Google Patents

Abstract

The present invention provides a coupled torsion beam axle for a vehicle, wherein a natural bump, rebound behavior occurring during the turning of the vehicle, and vertical angular rotation behavior of a trailing arm thereby are used to allow left and right tilting of the trailing arm according to the left or right transfer of the trailing arm, thereby increasing driving stability by inducing understeer when turning.

Description

Coupled torsion beam axle for vehicle}

The present invention relates to a coupled torsion beam axle (CTBA), which is one of a rear wheel suspension of a vehicle, and more specifically, a coupled torsion for a vehicle to induce an understeer during turning to increase turning stability. It is about the beam axle.

As is well known, the suspension system of a vehicle provides flexibility in the vertical direction to enable driving without affecting riding comfort even on irregular road surfaces, and responds to the horizontal and lateral forces generated by the wheels, and the braking and driving forces, as well as the body's It serves to suppress rolling.

Such suspension devices include axle beam type, pivot beam type, and coupled torsion beam axle (CTBA), among which a coupler torsion beam axle type is frequently used as a rear wheel suspension device for small and medium-sized passenger cars.

1, the coupled torsion beam axle (CTBA) type rear wheel suspension is provided with a torsion beam 101 extending in the vehicle width direction, and tires (not shown) at both ends of the torsion beam 101. The trailing arm 105 equipped with the carrier 103 for mounting the wheel and the one side is fixed by welding.

Further, each trailing arm 105 is equipped with a shock absorber 107 and a trailing arm bush 109 for connection with a vehicle body frame (not shown), and is also mounted on a spring seat 111 to support the vehicle body. Spring 113 is installed.

In particular, the coupled torsion beam axle, as shown in Figure 2, the torsion beam 101, carrier 103, trailing arm 105, trailing arm bush 109, spring seat 111 is integrated It is manufactured in a structure.

The coupled torsion beam axle is characterized in that the wheel is deformed due to the torsional deformation characteristics of the centrally located torsion beam 101, and the torsional deformation and the position of the trailing arm 105 and the characteristics of the bush 109 It has a feature that can be induced by toe-in during bump.

However, the conventional coupled torsion beam axle (CTBA) has a structure in which a torsion beam 101, a carrier 103, a trailing arm 105, a trailing arm bush 109, a spring seat 111, etc. are integrated. As it is made of, there is no function of wheel alignment, and there is a limit to induction of alignment due to behavior according to driving conditions.

In particular, there is a problem that the stability of the turning driving is somewhat unstable because it cannot cope with the behavior of natural bumps and rebounds during the turning driving.

The present invention has been devised to solve the above-described conventional problems, and using the natural bump and rebound behavior and the angular rotational motion of the trailing arm and the resulting natural bump and rebound behavior generated when the vehicle is turning, the left or the trailing arm An object of the present invention is to provide a coupled torsion beam axle for a vehicle that can increase driving stability by inducing understeering during turning while allowing left and right tilting of the trailing arm according to the right transfer.

In order to achieve the above object, the present invention includes: first and second trailing arms integrally mounted at left and right ends of the torsion beam, and first and second trailing arms mounted at the front end of each trailing arm. In a coupled torsion beam axle for a vehicle including a bush, the first and second trailing arm bushes are provided with an inner cylinder formed with a male screw on an outer diameter surface, and at the ends of the first and second trailing arms It is for an automobile characterized by integrally connecting an outer cylinder having an arm screw formed on an inner diameter surface, and rotating the female screw of the outer cylinder rotatably with respect to the male screw of the inner cylinder, and fixing the inner cylinder at a predetermined position in the vehicle body. Provides a coupled torsion beam axle.

Preferably, the screw spiral direction in which the female screw of the outer cylinder mounted on the end of the first trailing arm and the male screw of the inner cylinder constituting the first trailing arm bush mesh with each other, and of the second trailing arm The screw spiral direction in which the female screw of the outer cylinder mounted on the end and the male screw of the inner cylinder constituting the second trailing arm bush are engaged with each other is characterized in that they are formed opposite to each other.

Accordingly, when the rebound acts on the first trailing arm and the bump acts on the second trailing arm due to the centrifugal force caused by the left turning of the vehicle, the outer cylinder connected to the first trailing arm rotates upwards. At the same time, the outer cylinder connected to the second trailing arm rotates downwardly, so that the female screw of the outer cylinder connected to the first trailing arm is screwed to the left along the male screw of the inner cylinder and at the same time the second trailing arm It is characterized in that the female screw of the outer cylinder connected to the screw feeds to the left along the male screw of the inner cylinder.

Moreover, when the outer cylinder connected to the first trailing arm and the outer cylinder connected to the second trailing arm are positioned in the same left direction, a coupled torsion beam including a torsion beam connecting the first and second trailing arms It is characterized by a steer in which the axle is tilted to the left as a whole.

On the other hand, when a bump acts on the first trailing arm and a rebound acts on the second trailing arm due to centrifugal force when the vehicle is turning right, the outer cylinder connected to the first trailing arm rotates downwards at the same time. The outer cylinder connected to the second trailing arm rotates upwardly, so that the female screw of the outer cylinder connected to the first trailing arm is screwed to the right along the male screw of the inner cylinder and connected to the second trailing arm. It is characterized in that the female screw of the outer cylinder is screwed to the right along the male screw of the inner cylinder.

Furthermore, when the outer cylinder connected to the first trailing arm and the outer cylinder connected to the second trailing arm are positioned in the same right direction, a coupled torsion beam including a torsion beam connecting the first and second trailing arms It is characterized by a steer in which the axle is tilted to the right as a whole.

Through the above-described problem solving means, the present invention provides the following effects.

Using the natural bump and rebound behavior that occurs when the vehicle is turning, and the resulting angular rotation of the trailing arm, the screw is transported to the left or right side of the trailing arm, and coupled with the trailing arm. By allowing the left and right tilting of the torsion beam axle, understeer can be induced when turning, and thus driving stability can be improved when turning.

1 is a schematic diagram showing a rear wheel suspension of a coupled torsion beam axle (CTBA) type,
Figure 2 is a partially enlarged configuration diagram showing a coupled torsion beam axle for a vehicle according to the present invention,
Figure 3 is a schematic diagram showing the operating state of the trailing arm bush of the vehicle coupled torsion beam axle according to the present invention,
4A and 4B are schematic diagrams showing an operating state when a left-hand turning driving of a vehicle coupled torsion beam axle according to the present invention is performed;
5A and 5B are schematic diagrams showing an operating state when a right-hand turning of the coupled torsion beam axle for a vehicle according to the present invention is performed;
Figure 6 is a schematic diagram showing the principle of calculating the left and right transport distance and rear wheel steering angle of the trailing arm of the vehicle coupled torsion beam axle according to the present invention.

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

Attached FIG. 2 is a partially enlarged configuration diagram showing a coupled torsion beam axle for a vehicle according to the present invention, and FIG. 3 shows an operating state of a trailing arm bush of a vehicle for a coupled torsion beam axle according to the present invention As a schematic diagram, reference numeral 100 denotes a coupled torsion beam axle.

The coupled torsion beam axle 100 is applied to the rear wheel suspension of a vehicle, the torsion beam 101 arranged in the horizontal direction of the vehicle and the left and right ends of the torsion beam 101 are integrally connected to the vehicle body The trailing arm arranged along the front-rear direction, the trailing arm bush mounted on the front end of the trailing arm, and the spring seat 111 on which the spring of the suspension device mounted on the rear end of the trailing arm is seated It is manufactured in an integral structure.

In order to help understanding of the present invention, the trailing arms, which are respectively connected to the left and right ends of the torsion beam 101, are divided into a first trailing arm 105-1 and a second trailing arm 105-2. As described above, the trailing arm bush is also the front end of the first trailing arm bush 109-1 and the second trailing arm 105-2 mounted on the front end of the first trailing arm 105-1. The second trailing arm bush 109-2 mounted to the unit will be described separately.

According to the present invention, the first trailing arm bush 109-1 and the second trailing arm bush 109-2 have the same configuration, and are provided with an inner cylinder 130 on which the male screw 131 is formed on the outer diameter surface. do.

In addition, an outer cylinder 120 having an arm screw 121 formed on an inner diameter surface is integrally connected to ends of the first trailing arm 105-1 and the second trailing arm 105-2.

That is, the rear portion of the outer cylinder 120 is integrally connected to the front end portions of the first trailing arm 105-1 and the second trailing arm 105-2, respectively.

At this time, a fixed shaft 132 protrudes from the center of both sides of the inner cylinder 130 constituting the first trailing arm bush 109-1 and the second trailing arm bush 109-2. The inner cylinder 130 is fixed to the vehicle body by fixing the shaft 132 at a predetermined position in the vehicle body.

In particular, before mounting the inner cylinder 130 to the vehicle body, by fastening the female screw 121 of the outer cylinder 120 to the male screw 131 of the inner cylinder 130 so as to be transportable, the inner cylinder 130 and the outer cylinder 120 ) Is made, the male screw 131 and the female screw 121 are adopted as a ball screw type that is coupled with a ball therebetween for easy transport of the outer cylinder 120.

As described above, the first and second trailing arm bushes 109-1 and 109-2 are composed of an inner cylinder 130 provided with a structure in which a male screw 131 is formed on an outer diameter surface, and the first trailing arm ( 105-1) and the outer cylinder 120 integrally connected to the ends of the second trailing arm 105-2 is provided with a structure in which the female screw 121 is formed on the inner diameter surface, and the female screw of the outer cylinder 120 is provided. Coupled torsion beam of the present invention by fastening the 121 to the male screw 131 of the inner cylinder 130 so as to be rotatable and fixing the fixing shaft 132 of the inner cylinder 130 to a predetermined position in the vehicle body Assembly to the axle is made.

Meanwhile, as can be seen in FIGS. 4B and 5B, the female screw 121 of the outer cylinder 120 mounted on the end of the first trailing arm 105-1 and the first trailing arm bush 109 The screw spiral direction of the male screw 131 of the inner cylinder 130 constituting -1) and the female screw 121 of the outer cylinder 120 mounted at the end of the second trailing arm 105-2 ) And the screw spiral directions of the male screws 131 of the inner cylinder 130 constituting the second trailing arm bush 109-2 are formed opposite to each other.

The reason why the screw spiral direction is reversed is that rotational force of the first and second trailing arm bushes 109 and 109-2 is different from each other by bumps or rebounds during turning. Therefore, the outer cylinder 120 mounted on the end of the first trailing arm 105-1 and the outer cylinder 120 mounted on the end of the second trailing arm 105-2 during turning are the same. Screw feed in the direction.

Referring to FIG. 3, when bumps or rebounds are applied to a coupled torsion beam axle including a torsion beam and a trailing arm when the vehicle is turning, the first and the outer cylinders 120 and the outer tube 120 are integrated. Each of the second trailing arms 105-1 and 105-2 rotates around the inner cylinder 130 fixed to the vehicle body.

At this time, when the first and second trailing arms 105-1 and 105-2 rotate with each of the outer cylinders 120, the female screw 121 of the outer cylinder 120 is the male screw 131 of the inner cylinder 130. ), so that the screw transport (pitch transport) is performed, the outer cylinder 120 is positioned to one side or the other along the vehicle body width direction, and at the same time, the outer cylinder 120 and the first and second trails integrated therewith Steer of the coupled torsion beam axle 100 including the ring arms 105-1 and 105-2 and the torsion beam 101 connected to the first and second trailing arms 105-1 and 105-2 (as seen from above) Left or right tilting).

Here, the operation flow for the coupled torsion beam axle of the present invention having the above-described configuration will be described.

When turning left

Attached Figures 4a and 4b is a schematic diagram showing the operating state when the left-hand turning driving of the vehicle coupled torsion beam axle according to the present invention.

As shown in FIG. 4A, a rebound acts on the left side of the vehicle where the first trailing arm 105-1 exists due to centrifugal force when the vehicle is left turning, and at the same time, the vehicle having the second trailing arm 105-2. The bump will act on the right side.

For example, the outer cylinder 120 integral with the first trailing arm 105-1 rotates upward in the center of the inner cylinder 130 fixed to the vehicle body by rebounding, and simultaneously the second The outer cylinder 120 integral with the trailing arm 105-2 is rotated downwardly around the inner cylinder 130 fixed to the vehicle body by bumps.

Thus, the outer cylinder 120 connected to the first trailing arm 105-1 rotates in the upward direction at the same time, and the outer cylinder 120 connected to the second trailing arm 105-2 rotates in the downward direction. At this time, as shown in Figure 4b, the female screw 121 of the outer tube 120 connected to the first trailing arm 105-1 is screwed to the left along the male screw 131 of the inner tube 130. , Likewise, the female screw 121 of the outer cylinder 120 connected to the second trailing arm 105-2 is screwed to the left along the male screw 131 of the inner cylinder 130, and eventually the first The outer cylinder 120 connected to the trailing arm 105-1 and the outer cylinder 120 connected to the second trailing arm 105-2 are positioned to move in the same left direction.

Therefore, when the outer cylinder 120 connected to the first trailing arm 105-1 and the outer cylinder 120 connected to the second trailing arm 105-2 are moved in the same left direction, the first and first 2 The coupled torsion beam axle 100 including the torsion beam 101 and the like connecting the trailing arms 105-1 and 105-2 is entirely steered to the left, and is over when the vehicle is turning left. The steer can be suppressed and the understeer can be induced at the same time, thereby improving the turning stability.

When turning right

5A and 5B are schematic diagrams showing an operating state when a right-hand turning of the coupled torsion beam axle for a vehicle according to the present invention is performed;

As shown in FIG. 5A, a bump is applied to the left side of the vehicle where the first trailing arm 105-1 exists due to centrifugal force when the vehicle is turning right, and the vehicle having the second trailing arm 105-2 is present. The rebound will act on the right side.

For example, the outer cylinder 120 integral with the first trailing arm 105-1 rotates downward in the center of the inner cylinder 130 fixed to the vehicle body by bumps, and simultaneously the second The outer cylinder 120 integrally connected with the trailing arm 105-2 rotates upward in the center of the inner cylinder 130 fixed to the vehicle body by rebound.

Accordingly, the outer cylinder 120 connected to the first trailing arm 105-1 rotates in the downward direction at the same time, and the outer cylinder 120 connected to the second trailing arm 105-2 rotates in the upward direction. At this time, as shown in Figure 5b, the female screw 121 of the outer tube 120 connected to the end of the first trailing arm 105-1 moves the screw to the right along the male screw 131 of the inner tube 130. And, similarly, the female screw 121 of the outer cylinder 120 connected to the end of the second trailing arm 105-2 is screwed to the right along the male screw 131 of the inner cylinder 130, As a result, the outer cylinder 120 connected to the first trailing arm 105-1 and the outer cylinder 120 connected to the second trailing arm 105-2 are positioned to move in the same right direction.

Accordingly, when the outer cylinder 120 connected to the first trailing arm 105-1 and the outer cylinder 120 connected to the second trailing arm 105-2 are moved in the same right direction, the first and first 2 The coupled torsion beam axle 100 including the torsion beam 101 and the like connecting the trailing arms 105-1 and 105-2 is entirely steered to the right side, and is over when the vehicle is turning right. The steer can be suppressed and the understeer can be induced at the same time, thereby improving the turning stability.

On the other hand, referring to Figure 6 attached to the method for calculating the steer angle of the coupled torsion beam axle 100 for inducing understeer when the vehicle is equipped with the coupled torsion beam axle 100 when turning. .

The pitch at the time of one rotation of the outer tube 120, that is, the pitch at the time of one rotation of the outer tube 120 by the screw transfer of the female screw 121 of the outer tube 120 to the male screw 131 of the inner tube 130 is 10 cm Assuming to, and assuming that the angle of rotation of each trailing arm in the upward or downward direction of each trailing arm according to each rotation of the outer cylinder during bump and rebound is 20 degrees, the left and right transport distance of the outer cylinder is 5.6 mm.

In addition, assuming that the distance between the wheel center and the trailing arm (center of the outer cylinder) is 40 cm, the circumference of the circle in which the distance between the wheel center and the trailing arm (center of the outer cylinder) is calculated as a radius is 2.512 m.

Therefore, the distance between the wheel center and the trailing arm bush (center of the outer cylinder) is calculated as a radius, and the circumference of the circle (2.512m) versus the angle of the circle (360 degrees) is the left or right movement distance of the outer cylinder (0.0056m). Same as the steer angle (X) of the coupled torsion beam axle (coupled torsion beam axle including a trailing arm and torsion bar connected to the outer cylinder).

The steer angle X is equal to the steer angle of the wheel being steered together when the coupled torsion beam axle CTBA is steered.

That is, the distance between the wheel center and the trailing arm (center of the outer cylinder) is calculated by the radius of the circle (2.512m): the angle of the circle (360 degrees) = the left or right movement distance of the outer cylinder (0.0056m): coupled torsion beam It is equal to the steer angle (X) of the axle (CTBA).

Accordingly, the steer angle of the coupled torsion beam axle can be calculated to be 0.8 degrees.

As seen above, using the bump and rebound behavior and the angular rotational motion of the trailing arm that occur when the vehicle is turning, the screw is transported to the left or right of the trailing arm to the left or right while being integrated with the outer cylinder. By making the left and right steers (tilting) of the trailing arm and the coupled torsion beam axle, understeering can be induced while suppressing oversteering when turning, and thus driving stability can be improved when turning.

100: coupled torsion beam axle
101: torsion beam
103: carrier
105: trailing arm
105-1: 1st trailing arm
105-2: 2nd trailing arm
107: shock absorber
109: trailing arm bush
109-1: 1st trailing arm bush
109-2: 2nd trailing arm bush
111: spring seat
113: spring
120: external cylinder
121: female screw
130: inner tube
131: male screw
132: fixed shaft

Claims (6)

A coupled torsion beam axle for a vehicle including first and second trailing arms integrally mounted at left and right ends of a torsion beam, and first and second trailing arm bushes mounted at a front end of each trailing arm, respectively. In,
The first and second trailing arm bushes are provided with an inner cylinder having a male screw formed on an outer diameter surface, and an outer cylinder having an arm screw formed on an inner diameter surface is integrally connected to the ends of the first and second trailing arms, A coupling torsion beam axle for a vehicle, characterized in that the female screw of the outer cylinder is fastened to the male screw of the inner cylinder so as to be rotatable and fixed to the inner body at a predetermined position.
The method according to claim 1,
The screw spiral direction in which the female screw of the outer cylinder mounted on the end of the first trailing arm and the male screw of the inner cylinder constituting the first trailing arm bush interlock with each other, and mounted on the end of the second trailing arm A screw-coupled torsion beam axle for a vehicle, characterized in that the screw spiral directions in which the female screw of the outer cylinder and the male screw of the inner cylinder constituting the second trailing arm bush are mutually opposite.
The method according to claim 1,
When a rebound acts on the first trailing arm and a bump acts on the second trailing arm due to the centrifugal force caused by the left turning of the vehicle, the outer cylinder connected to the first trailing arm rotates upwards at the same time. The outer cylinder connected to the second trailing arm rotates downwardly, so that the female screw of the outer cylinder connected to the first trailing arm is screwed to the left along the male screw of the inner cylinder, and at the same time connected to the second trailing arm. An automotive coupled torsion beam axle, characterized in that the female screw of the outer cylinder is screwed to the left along the male screw of the inner cylinder.
The method according to claim 3,
When the outer cylinder connected to the first trailing arm and the outer cylinder connected to the second trailing arm are positioned in the same left direction, a coupled torsion beam axle including a torsion beam connecting the first and second trailing arms Vehicle-coupled torsion beam axle, characterized in that the steering is tilted to the left as a whole.
The method according to claim 1,
When a bump acts on the first trailing arm and a rebound acts on the second trailing arm due to centrifugal force during the right turning of the vehicle, the outer cylinder connected to the first trailing arm rotates downwards at the same time and secondly The outer cylinder connected to the trailing arm rotates upwards, so that the female screw of the outer cylinder connected to the first trailing arm is screwed to the right along the male screw of the inner cylinder and at the same time the outer cylinder connected to the second trailing arm An automobile coupled torsion beam axle, characterized in that the screw is screwed to the right along the male screw of the inner cylinder.
The method according to claim 5,
When the outer cylinder connected to the first trailing arm and the outer cylinder connected to the second trailing arm are positioned in the same right direction, a coupled torsion beam axle including a torsion beam connecting the first and second trailing arms Vehicle-coupled torsion beam axle, characterized in that the steering is tilted to the right as a whole.

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