JP2007015564A - Elastic bush for suspension - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an elastic bush for a suspension capable of replacing either a main bush or a stopper bush. <P>SOLUTION: The elastic bush for the suspension is provided with the main bush 32 fitted in an attachment shaft 31 attached to a chassis frame 16 and inserted into an attachment hole 23a formed on a base end of a suspension arm 23 in order to attach the base end of the arm 23 to the chassis frame 16, and the stopper bush 36 disposed on a hole edge of the attachment hole 23a. The main bush 32 is equipped with an outer cylinder 34 capable of being press-fitted into the attachment hole 23a, and a cylindrical elastic body 35 intervening between the outer cylinder 34 and the attachment shaft 31. The stopper bush 36 is provided with a short pipe part 37a capable of being fitted in the outer cylinder 34 and capable of being press-fitted into the attachment hole 23a, a ring-shaped flange part 37b having an inner edge continuously formed on one end of the short pipe part 37a and having an inner surface capable of being seated on a hole periphery edge of the attachment hole 23a, and a ring-shaped elastic body 38 adhered to an outer surface of the flange part 37b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a suspension elastic bush for attaching an arm of a vehicle suspension to a chassis frame.

Conventionally, independent suspensions represented by a so-called double wishbone type or the like have been adopted for front wheels of vehicles such as buses, and arms in this suspension are attached to chassis frames via elastic bushings. The suspension elastic bushing includes an elastic body, and the elastic body is interposed between the arm and the chassis frame, so that vibration generated in the suspension is prevented from being directly transmitted to the chassis frame, thereby improving the riding comfort in the vehicle. It can be improved.
On the other hand, the arm in the suspension swings with respect to the chassis frame and also moves in the vehicle longitudinal direction. Therefore, in the elastic bush for attaching the arm to the chassis frame, the main bush for attaching the base end of the suspension arm to the chassis frame so as to be swingable, and the stopper bush for suppressing the movement of the suspension arm in the longitudinal direction of the vehicle. One having both is known (for example, see Patent Document 1).
Japanese Utility Model Publication No. 4-75246 (utility model registration request, Fig. 1)

However, in the above-described conventional suspension elastic bush, the main bush and the stopper bush are integrally formed, so when one of them reaches the end of its life, it is necessary to replace the entire elastic bush including both of them. Therefore, it was difficult to make effective use of materials. In order to eliminate this point, it is conceivable to divide them. However, removing the elastic bush once attached makes reuse impossible. It is desirable not to interfere with each other.
An object of the present invention is to provide an elastic bush for a suspension in which one of a main bush and a stopper bush can be replaced.

As shown in FIG. 1, the invention according to claim 1 is inserted into an attachment hole 23 a that is fitted into an attachment shaft 31 attached to the chassis frame 16 and formed at the base end of the suspension arm 23 together with the attachment shaft 31. A main bush 32 that attaches the base end of the suspension arm 23 to the chassis frame 16 and a stopper bush 36 that is provided at the hole edge of the attachment hole 23a and suppresses the movement of the suspension arm 23 relative to the attachment shaft 31 in the axial direction. This is an improvement of the elastic bush for suspension.
The characteristic configuration is that the main bush 32 includes an outer cylinder 34 that can be press-fitted into the mounting hole 23 a, and a cylindrical elastic body 35 that is interposed between the outer cylinder 34 and the mounting shaft 31. The short tube portion 37a that can be fitted into the outer cylinder 34 and can be press-fitted into the mounting hole 23a, and the inner edge is formed continuously at one end edge of the short tube portion 37a, and the inner surface is formed at the peripheral edge of the mounting hole 23a There is a ring-shaped flange portion 37b that can be seated, and a ring-shaped elastic body 38 that is bonded to the outer surface of the flange portion 37b.

In the elastic bush for suspension according to the first aspect, the main bush 32 and the stopper bush 36 are divided and formed separately. The stopper bush 36 is configured to be fitted into the main bush 32. Therefore, when the life of the main bush 32 is reached, only the main bush 32 can be replaced without removing the stopper bush 36. When the life of the stopper bush 36 is reached, the main bush 32 is removed. Only the stopper bush 36 can be replaced. As a result, the material can be effectively used.
The invention according to claim 2 is the invention according to claim 1, wherein the cylindrical elastic body 35 has a larger elastic modulus than the ring-shaped elastic body 38.
With the elastic bush for suspension according to the second aspect, the ride comfort in the vehicle can be improved.

  In the elastic bush for suspension of the present invention, the mounting shaft attached to the chassis frame can be press-fitted, and the outer tube that can be press-fitted into the mounting hole formed at the base end of the suspension arm, the outer tube and the mounting shaft For the main bush provided with a cylindrical elastic body interposed between the stopper bush, the stopper bush can be fitted into the outer cylinder and can be press-fitted into the mounting hole, It has a ring-shaped flange part with an inner edge continuously formed on one end edge and an inner surface seated on the periphery of the mounting hole, and a ring-shaped elastic body bonded to the outer surface of the flange part. The bush and the stopper bush are divided and formed separately. Since the stopper bushing is configured to be able to fit into the main bushing, when the life of the main bushing is reached, only the main bushing can be replaced without removing the stopper bushing, and the life of the stopper bushing has been reached. In this case, only the stopper bush can be replaced without removing the main bush. Here, if the elastic modulus of the cylindrical elastic body is larger than the elastic modulus of the ring-shaped elastic body, the riding comfort can be improved.

Next, the best mode for carrying out the present invention will be described with reference to the drawings.
As shown in FIG. 5, a chassis frame 16 of a bus 10 that is a vehicle is provided with a pair of side members 16a and 16a extending in the traveling direction of the bus 10, and below the front portions of the pair of side members 16a and 16a. A front lower member 16b fixed to the side members 16a and 16a and a rear lower member 16c provided below the rear of the pair of side members 16a and 16a and fixed to the side members 16a and 16a. The rear portion of the chassis frame 16 is suspended by a rigid air suspension 11. The rigid air suspension 11 has an axle housing 13 that rotatably holds the rear axle 12, and left and right installations extending substantially in the traveling direction (forward direction and backward direction) of the bus 10 with the center substantially fixed to the left and right lower surfaces of the axle housing 13. The members 14 and 14 and a total of four air springs 15 installed at the front and rear ends of the erection members 14 and 14 and having upper ends fixed to the lower surface of the rear lower member 16c, respectively. The left and right rear wheels 19, 19 are fixed to both ends of the rear axle 12 extending in the vehicle width direction.

  On the other hand, the front portion of the chassis frame 16 of the bus 10 is suspended by an independent suspension type air suspension 21. The independent suspension type air suspension 21 on the left side of the bus 10 will be described as a representative. As shown in detail in FIGS. 3 and 4, the independent suspension type air suspension 21 in this embodiment is a double wishbone type suspension. An upper arm 23 having a base end pivotally attached to the front lower member 16b and a tip end pivotally attached to the support shaft 22, and a base end positioned below the upper arm 23 and pivotally attached to the front lower member 16b, and the tip end pivoted to the support shaft 22. And a pneumatic spring 25 having a lower end fixed to the upper end of the support shaft 22 and an upper end fixed to the lower surface of the front sub-member 16d (FIG. 5). Here, referring back to FIG. 5, the front sub-member 16d extends outside the pair of side members 16a, 16a to the pair of front cross members 16e, 16e fixed in the vehicle width direction to the front portions of the pair of side members 16a, 16a. And extend in the direction of travel of the bus 10 and are fixed to each other. The base ends of the left and right front axles 27, 27 are fixed to the left and right support shafts 22, 22, respectively, extending in the vertical direction, and the left and right front wheels 26, 26 are the front ends of the left and right front axles 27, 27 extending in the vehicle width direction. Each is mounted rotatably.

  In this independent suspension type air suspension 21, when a load is applied to the front wheel 26 due to road surface irregularities while the bus 10 is traveling, the front wheel 26 moves in the vertical direction together with the front axle 27 and the support shaft 22, and the air spring 25 is supported. The movement of the shaft 22 in the vertical direction is attenuated to absorb the vibration, thereby improving the riding comfort of passengers on the bus 10. Here, the upper arm 23 and the lower arm 24 each having the support shaft 22 pivotally attached to the tip end move up and down together with the support shaft 22 with their base ends as fulcrums, and the support shaft 22 is allowed to move up and down. The support shaft 22 is configured to be prohibited from moving in the horizontal direction.

  As shown in detail in FIG. 3, the upper arm 23 and the lower arm 24 are respectively formed so that the proximal end side extends from the distal end where the support shaft 22 is pivoted to the proximal end, and the proximal ends of the upper arm 23 and the lower arm 24 are respectively The front end and the rear end are pivotally attached to the front lower member 16b, which is the chassis frame 16, via the elastic bush 30 of the present invention. Since the elastic bushes 30 of the present invention in which the front end and the rear end at the base ends of the upper arm 23 and the lower arm 24 are respectively pivotally attached to the front lower member 16b have the same structure, the base end of the upper arm 23 shown in FIG. The elastic bush 30 that attaches the rear end to the chassis frame 16 will be described below as a representative.

  As shown in detail in FIGS. 1 and 2, the elastic bush 30 includes a main bush 32 and a stopper bush 36. The main bush 32 is fitted into a mounting shaft 31 attached to the chassis frame 16 and is inserted into a mounting hole 23a formed at the base end of the arm 23 together with the mounting shaft 31 so that the base end of the upper arm 23 serving as a suspension arm. Is attached to the chassis frame 16. The attachment shaft 31 is attached to a pair of female screw portions 16f, 16f projecting from the chassis frame 16 in the vehicle width direction via bolts 29, whereby the attachment shaft 31 is attached to the pair of female screw portions 16f, 16f on the bus 10. It is installed parallel to the direction of travel. The main bush 32 includes a metal outer cylinder 34 that can be press-fitted into the mounting hole 23 a, and a cylindrical elastic body 35 that is interposed between the outer cylinder 34 and the mounting shaft 31. Both ends of the outer cylinder 34 are processed to have a reduced diameter so that the press-fitting into the mounting hole 23a can be facilitated. In the main bush 32, when the tip of the upper arm 23 moves up and down as shown by a solid line arrow in FIG. 2, the outer cylinder 34 rotates with respect to the mounting shaft 31, and the cylindrical elastic body 35 interposed therebetween is The elasticity allows the rotation and prevents the vibration generated when the tip of the upper arm 23 moves up and down from being directly transmitted to the chassis frame 16 to improve the riding comfort on the bus 10. The

  On the other hand, the stopper bush 36 includes a metal ring 37, and the metal ring 37 can be fitted into the outer cylinder 34 of the main bush 32 and can be press-fitted into a mounting hole 23 a formed at the base end of the arm 23. An inner edge is formed continuously at one end edge of the short pipe portion 37a, and a ring-shaped flange portion 37b whose inner surface can be seated on the peripheral edge of the attachment hole 23a. The mounting hole 23 a has a small diameter portion into which the outer cylinder 34 in the main bush 32 is press-fitted, and a large diameter portion into which a short pipe portion 37 a that can be fitted into the outer cylinder 34 is pressed, and the short pipe portion in the metal ring 37. 37a is press-fitted into the large diameter portion in the mounting hole 23a.

  The stopper bush 36 includes a metal ring 37 and a ring-shaped elastic body 38 bonded to the outer surface of the flange portion 37b. Thus, the stopper bush 36 provided on the peripheral edge of the mounting hole 23a of the upper arm 23 is such that when the upper arm 23 attempts to move in the axial direction with respect to the mounting shaft 31, the tip of the ring-shaped elastic body 38 is attached to the mounting shaft. When the upper arm 23 tries to move further, the ring-shaped elastic body 38 is interposed between the peripheral edge of the mounting hole 23a of the upper arm 23 and the female screw portion 16f. In addition to suppressing the vibration, the vibration generated when the tip of the upper arm 23 comes into contact with the female screw portion 16f is prevented from being directly transmitted to the chassis frame 16, thereby improving the riding comfort on the bus 10. . Here, the ring-shaped elastic body 38 is made of rubber, urethane or the like, and the cylindrical elastic body 35 is made of rubber or the like. And this cylindrical elastic body 35 is comprised so that an elasticity modulus may become larger than the ring-shaped elastic body 38, and, thereby, riding comfort can be improved.

  1 and 2 illustrate the elastic bush 30 for attaching the rear end of the base end of the upper arm 23 to the chassis frame 16, so that the stopper bush 36 is press-fitted into the attachment hole 23a from the rear of the bus. Indicates. Although not shown, in the elastic bush 30 for attaching the front ends of the upper arms 23 and the lower arms 24 to the chassis frame 16, the stopper bush 36 is press-fitted into the attachment hole 23a from the front of the bus. Accordingly, when the upper arm 23 and the lower arm 24 try to move rearward with respect to the mounting shaft 31 parallel to the traveling direction of the bus 10, the ring-shaped elastic body in the stopper bush 36 that is press-fitted from the rear to the rear end of their base ends. When the upper arm 23 and the lower arm 24 try to move forward with respect to the mounting shaft 31, they are pressed into the front ends of their base ends from the front. Further, the ring-like elastic body 38 in the stopper bush 36 abuts on the female screw portion 16f in the chassis frame to suppress further movement.

  In the suspension elastic bush 30 configured as described above, the main bush 32 and the stopper bush 36 are divided and formed separately. The short pipe portion 37 a that defines the inner diameter of the stopper bush 36 is configured to be fitted into the outer cylinder 34 that defines the outer diameter of the main bush 32, so that the stopper bush 36 is fitted into the main bush 32. Configured to be possible. Therefore, for example, when the life of the main bush 32 is reached, only the main bush 32 is extracted from the mounting hole 23a without removing the stopper bush 36, and the stopper bush 36 is press-fitted into the remaining mounting hole 23a. By press-fitting the main bush 32, only the main bush 32 can be replaced. When the stopper bush 36 has reached the end of its service life, only the stopper bush 36 is removed from the mounting hole 23a without removing the main bush 32, and the main bush 32 is press-fitted into the hole edge of the remaining mounting hole 23a. By press-fitting a new stopper bush 36, only the stopper bush 36 can be replaced. As a result, the material can be effectively used.

It is the A section expanded sectional view of Drawing 3 showing the elastic bush for suspensions of the embodiment of the present invention. It is the side view which looked at the base end of the arm attached using the elastic bush from the front. It is a top view of the suspension. It is a front view of the suspension. It is a block diagram of the skeleton of a bus provided with the suspension.

Explanation of symbols

16 Chassis frame 23 Upper arm (Suspension arm)
23a Mounting hole 31 Mounting shaft 32 Main bush 34 Outer cylinder 35 Cylindrical elastic body 36 Stopper bush 37a Short pipe portion 37b Flange portion 38 Ring-shaped elastic body

Claims (2)

The suspension arm is inserted into a mounting hole (23a) which is inserted into a mounting shaft (31) attached to the chassis frame (16) and formed at the base end of the suspension arm (23) together with the mounting shaft (31). A main bush (32) for attaching the base end of (23) to the chassis frame (16), and a shaft with respect to the attachment shaft (31) of the suspension arm (23) provided at the hole edge of the attachment hole (23a) In the elastic bush for suspension provided with a stopper bush (36) that suppresses movement in the direction,
The main bush (32) includes an outer cylinder (34) that can be press-fitted into the mounting hole (23a), and a cylindrical elastic body (between the outer cylinder (34) and the mounting shaft (31)). 35)
The stopper bush (36) can be fitted into the outer cylinder (34) and can be press-fitted into the mounting hole (23a), and one end of the short pipe portion (37a). A ring-shaped flange portion (37b) in which an inner edge is continuously formed on the edge and an inner surface can be seated on the periphery of the hole of the mounting hole (23a), and a ring-shaped elastic body bonded to the outer surface of the flange portion (37b) (38) and an elastic bush for suspension. The elastic bush for suspension according to claim 1, wherein the cylindrical elastic body (35) has a larger elastic modulus than the ring-shaped elastic body (38).

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