JP2003227546A - Vibration isolating device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration isolating device and its manufacturing method which drastically improves productivity while maintaining excellent durability. <P>SOLUTION: In this vibration isolating device, a rubber elastic body 3 is provided between a shaft member 1 and an outer cylinder 2, the outer cylinder 2 is fixed to an inner circumferential face of a connecting bracket 4, and a slit 5 is formed in the axial direction of the outer cylinder 2, and the manufacture of the vibration isolating device comprises processes of: forming the vibration isolating device with an interval L of the slit 5 set so that the outer diameter of the outer cylinder 2 when the cylinder is deformed till both ends 5A of the slit 5 are brought into contact with each other is larger than the inner diameter of the connecting bracket 4 and the outer cylinder 2 having the slit 5 by bending a board material 2A; vulcanizing and bonding the rubber elastic body 3 between the shaft member 1 and the outer cylinder 2 to have a partly- finished product; and pressing the outer cylinder 2 of the partly-finished product into the inner peripheral face of the connecting bracket 4. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolator used for automobile suspension arms, engine mounts and the like, and a method for manufacturing the same, and particularly to a vibration isolator excellent in durability and productivity and its manufacture. It is about the method.

[0002]

2. Description of the Related Art Conventionally, by providing a rubber elastic body between a shaft member and an outer cylinder and fixing the outer cylinder to a connecting bracket,
There is known a vibration isolation device that blocks transmission of vibration between a shaft member and a connecting bracket. This type of vibration damping device, after vulcanizing and adhering the rubber elastic body to the shaft member and the outer cylinder,
It is manufactured by pressing the outer cylinder into the inner peripheral surface of the connecting bracket.

As the outer cylinder, a pipe material is cut and both end faces are cut, or a plate material is bent into a cylindrical shape and then abutting portions are welded. Also, in order to alleviate the heat shrinkage after vulcanization and adhesion of the rubber elastic body and improve the durability, the outer cylinder is previously drawn so as to be compressed and deformed in the radial direction before being press-fitted into the connecting bracket. Was there.

[0004]

However, it is difficult to use the outer cylinder as a pipe material because the pipe material itself is expensive, and the welding of the plate material causes a problem in productivity. Further, it is the same that any outer cylinder needs to go through two steps of drawing and press fitting. Moreover,
Since high dimensional accuracy is required in order to obtain sufficient fixing strength by press fitting, it is difficult to use the drawn outer cylinder as it is, and it is necessary to polish it.

On the other hand, a method may be considered in which the outer cylinder is omitted and the rubber elastic body vulcanized and bonded to the shaft member is directly inserted into the inner peripheral surface of the connecting bracket while being compressed, but the outer cylinder is used. Since the rigidity is lower than that in the case where it is carried out, there arises a problem in durability.

Therefore, an object of the present invention is to provide an anti-vibration device and a manufacturing method thereof, which can significantly improve the productivity while ensuring excellent durability by using an outer cylinder. is there.

[0007]

The present invention has been made to solve the above problems, and a first gist thereof is to provide a rubber elastic body between a shaft member and an outer cylinder, A vibration damping device in which an outer cylinder is fixed to the inner peripheral surface of a connecting bracket, and a slit is formed in the axial direction of the outer cylinder, and the outer diameter of the outer cylinder when deformed until both ends of the slit come into contact with each other is The present invention relates to a vibration isolator in which the slit spacing is set so as to be equal to or larger than the inner diameter of the connecting bracket.

Preferably, at least one end of the connecting bracket in the axial direction is an inwardly inclined surface, and more preferably, at least one end of the outer cylinder in the axial direction engages with the connecting bracket. The present invention relates to a vibration isolation device. Here, the locking claw is preferably formed by a notch in the axial direction of the outer cylinder, and further, the locking claw is preferably fitted in the locking groove of the connecting bracket.

The second gist of the present invention is to bend a plate material to form an outer cylinder having slits, and to vulcanize and bond a rubber elastic body between the shaft member and the outer cylinder to form an intermediate member. The present invention relates to a method for manufacturing the above vibration isolator, which comprises a step of making a product and a step of press-fitting the outer cylinder of the intermediate product to the inner peripheral surface of the connecting bracket, and preferably the inner peripheral surface of the connecting bracket. At the same time that the outer cylinder is press-fitted, the outer cylinder is deformed toward the outside of the connecting bracket.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The vibration isolator of the present invention is similar to the conventional one in that a rubber elastic body is provided between the shaft member and the outer cylinder, and the outer cylinder is fixed to the inner peripheral surface of the connecting bracket. That is, by providing a rubber elastic body, vibration transmission between the shaft member and the connecting bracket is blocked, and by using the outer cylinder, excellent durability is secured.

The vibration damping device of the present invention is characterized by:
A slit is formed in the axial direction of the outer cylinder. That is, even when the plate material is bent into a cylindrical shape, the abutting portions are not welded as in the conventional case and a certain distance is left. Therefore, the welding process becomes unnecessary and the productivity is improved.

Further, due to the presence of the slit, the outer cylinder can be easily compressed and deformed in the radial direction. That is, until both ends of the slit come into contact with each other, only the repulsive force of the rubber elastic body hinders the deformation in the radial direction. Therefore, when the pipe material is used as an outer cylinder as it is or the butted portion of the bent plate material is used. Compared to the case of welding, the material deforms with a much lower compression force.

Therefore, the method of manufacturing the vibration damping device of the present invention is
A step of bending the plate material to form an outer cylinder having a slit; a step of vulcanizing and adhering a rubber elastic body between the shaft member and the outer tube to form an intermediate product; Only the step of press-fitting the outer product cylinder is required. As described above, the vibration damping device of the present invention can compressively deform the outer cylinder together when the outer cylinder is inserted into the inner peripheral surface of the connecting bracket, and as a result, it is not necessary to perform the drawing process in advance. Productivity is greatly improved.

Further, the interval between the slits is set so that the outer diameter of the outer cylinder when deformed until both ends of the slit come into contact with each other is equal to or larger than the inner diameter of the connecting bracket.
With the slits having such intervals, when the outer cylinder is inserted into the connecting bracket, necessary and sufficient precompression can be given to the rubber elastic body with a relatively low insertion pressure until the slit is closed. On the other hand, since a large force input is required for insertion after the slit is closed, the outer cylinder is firmly fixed to the connecting bracket.

Moreover, the pre-compression of the rubber elastic body and the press-fitting of the outer cylinder are performed almost at the same time, and the dimensional accuracy of the outer cylinder does not deteriorate before the press-fitting. Since it is not necessary to apply, it is possible to achieve both high durability and high productivity.

Here, the degree of pre-compression with respect to the rubber elastic body can be adjusted by appropriately adjusting the interval between the slits according to the rubber quality and size of the elastic body. That is, increasing the slit spacing increases the pre-compression of the rubber elastic body,
The smaller the slit spacing, the smaller the precompression.

Further, since the fixing force between the outer cylinder and the connecting bracket correlates with the pressure input, the relationship between the outer diameter of the outer cylinder and the inner diameter of the connecting bracket when the slits are deformed until they contact each other. The fixing force can be adjusted by appropriately setting. That is, the fixing force can be increased by increasing the outer diameter of the outer cylinder with respect to the inner diameter of the connecting bracket. However, it is natural that there is a limit in relation to press-fitting, and if the outer diameter of the outer cylinder is made too large, not only the fixing force will not increase, but also press-fitting work will not be possible.

As described above, according to the vibration isolator of the present invention, the pre-compression of the rubber elastic body and the press-fitting of the outer cylinder are performed in one step. However, in order to facilitate the press-fitting work, the axial direction of the connecting bracket is increased. It is preferable that at least one end of the is an inwardly inclined surface. That is, by utilizing the inwardly inclined surface as a guide at the time of press-fitting, the outer cylinder can be easily deformed in the radial direction.

For smooth press-fitting work, it is desirable that the difference between the outer diameter of the outer cylinder and the inner diameter of the connecting bracket after the slit is closed is small. However, if the difference between the two is small, the fixing force also decreases accordingly. Therefore,
It is preferable to provide a locking claw with the connecting bracket at least at one end in the axial direction of the outer cylinder.

For example, if the end portion of the outer cylinder is bent along the inclined surface of the end portion of the connecting bracket to form the locking claw, the axial disengagement can be more reliably prevented. It is sufficient that the locking claws can be prevented from slipping out in the expected direction. However, if both ends of the connecting bracket are inclined surfaces and both ends of the outer cylinder are bent, the locking claws can be engaged in any direction. Become a nail.

For the locking claw, for example, the outer cylinder is used as it is,
It can be formed by notching the end of the outer cylinder in the axial direction. A plurality of notches are formed if necessary, and if there is a slit at a position of 0 ° in the circumferential direction, 90 °,
It may be provided at three positions of 180 ° and 270 °.

It is also effective that the locking claws are fitted in the locking grooves of the connecting bracket. That is, when both ends of the outer cylinder are bent along the inclined surface of the connecting bracket to form the locking claws, the locking claws are prevented in the axial direction, but do not contribute to the prevention of rotation in the circumferential direction. Therefore, a locking groove is provided in the connecting bracket to engage with the locking claw to restrain the movement in the circumferential direction.

The locking claw may be made to exhibit its function by press-fitting the outer cylinder to the inner peripheral surface of the connecting bracket and then bending the outer cylinder separately. It is preferable that the engaging claw is formed by deforming the connecting bracket toward the outside. For example, the press-fitting jig may be provided with an inclined portion corresponding to the inclined surface of the connecting bracket, and the inclined portion of the press-fitting jig may bend the locking claw when the press-fitting is completed.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific examples of preferred embodiments of the present invention will be described below with reference to the drawings. 1A and 1B are views showing an example of an intermediate product in the vibration isolator of the present invention. FIG. 1A is a top view thereof, FIG. 1B is a side view, and FIG. 1C is FIG. )
FIG. 2 is a diagram showing a vibration isolator using the intermediate product of FIG. 1, FIG. 2 (A) is a top view thereof, and FIG. 2 (B) is a sectional view taken along line BB of FIG. 2 (A). Is.

As shown in FIG. 1, the intermediate product of the vibration isolator of the present invention has a rubber elastic body 3 provided between the shaft member 1 and the outer cylinder 2, and has a space in the axial direction of the outer cylinder 2. An L slit 5 is formed. Further, locking claws 6 formed by notches in the axial direction are provided at both ends in the axial direction of the outer cylinder 2.

Here, the interval L between the slits 5 is set so that the outer diameter of the outer cylinder 2 when it is deformed until both ends 5A contact each other is larger than the inner diameter of the connecting bracket 4 shown in FIG. Has been done. Therefore, in the completed vibration damping device shown in FIG. 2, the outer cylinder 2 is press-fitted into the inner peripheral surface of the connecting bracket 4, and the outer cylinder 2 and the connecting bracket 4
And are firmly fixed.

Next, this point will be described in more detail based on the method of manufacturing the vibration isolator of the present invention shown in FIG. Due to the presence of the slits, as shown in FIG. 3, the outer diameter of the outer cylinder 2 before press fitting is larger than the inner diameter of the connecting bracket 4.
Therefore, the outer cylinder 2 cannot be inserted into the connecting bracket 4 as it is. Therefore, a load is applied to the press fitting jig 10. Then, the outer cylinder 2 is attached to the inclined surface 4A of the connecting bracket 4.
Is compressed and deformed in the radial direction.

At this time, in the slit 5 shown in FIG.
Until the state before both ends 5A contact each other (L ≧
0) is easily deformed even when the press-fitting load is small, and the rubber elastic body 3 is given necessary and sufficient precompression. On the other hand, even after the slit 5 is closed (L = 0), since the outer diameter of the outer cylinder 2 is larger than the inner diameter of the connecting bracket 4, the outer cylinder 2 can be press-fitted thereafter unless a considerable load is applied. Disappear. Therefore, the vibration isolation device of FIG.
A high contact pressure acts between the connection bracket 4 and the connection bracket 4, and serves as a fixing force.

The press-fitting jig 10 shown in FIG. 3 has an inclined portion 10A corresponding to the inclined surface 4A of the connecting bracket 4. Therefore, when the press-fitting is completed, the inclined portion 10A has the locking claw 6
Fold. As a result, as shown in FIG. 2, the locking claws 6 restrain both ends of the connecting bracket 4 and prevent the outer cylinder 2 from coming off in the axial direction.

FIG. 4 is a diagram showing a method for manufacturing an outer cylinder used in the vibration isolator of the present invention. FIG. 4 (A) is a developed view of the outer cylinder, FIG. 4 (B) is its top view, and FIG. 4 (C) is a side view. As shown in FIG. 4, the outer cylinder 2 is formed by bending a plate material 2A. That is, the plate material 2A is provided with notches at equal intervals to form the locking claws 6, and then the plate material 2A is roll-bent to form the outer cylinder 2 having the slits 5.

According to the method shown in FIG. 4, the inexpensive plate material 2A is used.
The outer cylinder 2 can be formed by using, and the welding is not required only by performing the roll bending. When the circumferential position of the slit 5 is 0 °, the locking claw 6 is 90 °,
It exists at the positions of 180 ° and 270 °.

[0032]

According to the vibration isolator and the method of manufacturing the same of the present invention, a slit is formed in the axial direction of the outer cylinder, and the outer diameter of the outer cylinder when deformed until both ends of the slit come into contact with each other, ,
Since the slit spacing is set so that it is equal to or larger than the inner diameter of the connecting bracket, vibration transmission between the shaft member and the connecting bracket is blocked, ensuring excellent durability, and the outer cylinder can be drawn and polished. It becomes unnecessary, the manufacturing process is simplified, and the productivity is greatly improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of an intermediate product in a vibration isolation device of the present invention.

FIG. 2 is a diagram showing a vibration isolation device using the intermediate product of FIG.

FIG. 3 is a diagram showing an example of a method for manufacturing a vibration isolation device according to the present invention.

FIG. 4 is a diagram showing an example of a method for manufacturing an outer cylinder used in the vibration isolator of the present invention.

[Explanation of symbols]

1 ... Shaft member 2 ... Outer cylinder 2A: Plate material that becomes the outer cylinder 3. Rubber elastic body 4 Connection bracket 4A ... Inclined surface of connecting bracket 5 ... Slit 5A: Both ends of the slit 6 ... locking claw 10: Press-fitting jig 10A ... Inclined part of press-fitting jig L: Slit spacing

Claims (7)

[Claims] 1. A vibration isolator in which a rubber elastic body (3) is provided between a shaft member (1) and an outer cylinder (2), and the outer cylinder (2) is fixed to an inner peripheral surface of a connecting bracket (4). The outer diameter of the outer cylinder (2) when the slit (5) is formed in the axial direction of the outer cylinder (2) and is deformed until both ends (5A) of the slit (5) contact each other. The anti-vibration device, wherein the interval (L) of the slits (5) is set so as to be equal to or larger than the inner diameter of the connecting bracket (4). 2. The vibration isolator according to claim 1, wherein at least one end of the connecting bracket (4) in the axial direction is an inwardly inclined surface (4A). 3. The vibration proof according to claim 1, wherein a locking claw (6) for engaging with the connecting bracket (4) is provided on at least one end of the outer cylinder (2) in the axial direction. apparatus. 4. The vibration isolator according to claim 3, wherein the locking claw (6) is formed by a notch in the axial direction of the outer cylinder (2). 5. The locking claw (6) has a connecting bracket (4).
5. The fitting groove is fitted in the locking groove of the above.
The anti-vibration device described in. 6. A step of bending a plate material (2A) to form an outer cylinder (2) having a slit (5), and a rubber elastic body () between the shaft member (1) and the outer cylinder (2). 3. A step of vulcanizing and adhering 3) to form an intermediate product, and a step of press-fitting the outer cylinder (2) of the intermediate product into the inner peripheral surface of the connecting bracket (4). 5. The method for manufacturing the vibration damping device according to any one of 5 above. 7. The outer cylinder (2) is pressed into the inner peripheral surface of the connecting bracket (4), and at the same time, the outer cylinder (2) is deformed toward the outside of the connecting bracket (4). 7. The method for manufacturing a vibration isolator according to item 6.