JP4323109B2 - Anti-vibration bushing manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an anti-vibration bush used for an automobile or the like and a method for manufacturing the same.
[0002]
[Prior art and problems to be solved by the invention]
2. Description of the Related Art Conventionally, for example, in a suspension mechanism of an automobile, a cylindrical vibration isolating bush is used as a vibration isolating device that connects a vehicle body and a suspension member in a vibration isolating manner.
[0003]
FIG. 6 shows a cross section of the conventional vibration-proof bushing 100 during vulcanization molding. The anti-vibration bush 100 includes an inner cylinder 101 and an outer cylinder 102 arranged concentrically, and a rubber elastic body 103 interposed therebetween, and is fastened to a vehicle body panel at one end of the inner cylinder 101. A flange 105 having a surface 104 is provided. When this anti-vibration bush 100 is vulcanized and molded, a mold 110 composed of a left and right one mold 111 and the other mold 112 and an intermediate upper mold 113 and an intermediate lower mold 114 therebetween is used. On the other hand, the mold 111 is provided with a recess 115 for receiving the flange 105 of the inner cylinder 101, and vulcanization molding is performed with the peripheral wall of the flange 105 surrounded by the side surface of the recess 115.
[0004]
However, in this case, it is necessary to secure a certain gap between the side surface of the recess 115 and the peripheral wall of the flange 105 in consideration of the mold closing workability and the like. There is a problem that rubber enters the surface 104 and a rubber burr 120 is generated on the fastening surface 104.
[0005]
FIG. 7 is a cross-sectional view at the time of vulcanization molding of an anti-vibration bush 130 according to another conventional example. In this example, rubber is also molded on the outer periphery of the flange 105. In this case, only the contact between the fastening surface 104 of the flange 105 and the wall surface of the recess 115 in the one-side mold 111 prevents the rubber from entering the fastening surface 104, so that the rubber burr 120 is likely to occur on the fastening surface 104.
[0006]
The rubber burr 120 on the fastening surface 104 is loosened by the rubber sag when it is assembled to the mating part as it is. Therefore, it is necessary to remove the rubber burr 120 after the vulcanization molding, which increases the processing cost.
[0007]
The present invention has been made in view of such a point, and an object thereof is to prevent rubber burrs on a fastening surface of a flange provided at an end portion of an inner cylinder.
[0009]
[Means for Solving the Problems]
The vibration-proof bushing manufacturing method according to the present invention is a bush for connecting the first member and the second member in a vibration-proof manner, and a rubber elastic body is provided on the outer periphery of the inner cylinder attached to the first member. Anti-vibration in which a flange having a fastening surface to the first member is provided at the end of the inner cylinder, and a non-fastening surface portion is provided at a peripheral portion of the fastening surface via a stepped portion. A method of manufacturing a bush, wherein when the rubber elastic body is vulcanized and molded, a pressing surface portion provided on a mold is pressed against the non-fastening surface portion to prevent rubber from entering the fastening surface on the inside. It is to prevent.
[0010]
With this anti-vibration bush, a non-fastening surface portion that is dropped through a step portion is provided at the peripheral portion of the fastening surface of the inner cylinder end portion, so that the cavity of the molding die can be used during vulcanization molding of a rubber elastic body This non-fastened surface portion can act as a seal surface portion that seals the intrusion of the rubber that is going to get over the flange from the inside and enter the fastening surface, and rubber burr on the fastening surface can be prevented. That is, the pressing surface portion of the mold is pressed against the non-fastening surface portion to prevent the rubber from entering the fastening surface. However, since the object to be pressed is the non-fastening surface, even if surface roughening occurs due to pressing, the first It does not affect the fastening with the member. Therefore, a sealing projection extending in the circumferential direction can be provided on the pressing surface portion of the mold, and the projection can be pressed against the non-fastening surface portion, thereby preventing the rubber from entering the fastening surface more effectively.
[0011]
The anti-vibration bush of the present invention includes an outer cylinder attached to the second member, the outer cylinder surrounds the inner cylinder in an axial parallel manner, and the rubber elastic body is fixed to the inner periphery thereof by vulcanization molding. The outer cylinder may be provided with a flange facing the flange of the inner cylinder, and a part of the rubber elastic body may be interposed between the flanges.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0013]
FIG. 1 is a cross-sectional view of an anti-vibration bush 10 according to an embodiment of the present invention in a vehicle assembled state, FIG. 2 is a plan view of the anti-vibration bush 10 and FIG. 3 is a cross-sectional view during vulcanization molding. is there.
[0014]
The anti-vibration bush 10 is used to connect the vehicle body panel 1 and the suspension member 2 in an anti-vibration manner, and includes a metallic inner cylinder 12 and an outer cylinder 14 disposed concentrically at intervals, A rubber elastic body 16 is provided between the inner and outer cylinders 12 and 14 by vulcanization molding and integrally couples the cylinders.
[0015]
At one end portion of the inner cylinder 12 attached to the vehicle body panel 1, a flange 20 having a fastening surface (that is, a coupling surface) 18 for the vehicle body panel 1 on the outer side in the axial direction is provided. The flange 20 is erected outward in the radial direction on the entire circumference of the inner cylinder 12. The inner cylinder 12 includes an insertion portion 22 that is inserted into the mounting hole 3 of the vehicle body panel 1 on the axial front end side of the flange 20. A nut 4 is welded to the mounting hole 3 of the vehicle body panel 1. With the bolt 5 inserted through the inner cylinder 12, the distal end insertion portion 22 is inserted into the mounting hole 3, and the fastening surface 18 of the flange 20 is attached. The inner cylinder 12 is fixedly attached to the vehicle body panel 1 by tightening the bolt 5 together with the nut 4 against the peripheral edge of the mounting hole 3.
[0016]
At one end portion of the outer cylinder 14 attached to the suspension member 2, a flange 24 that is opposed to the flange 20 of the inner cylinder 12 in the axial direction is provided. The outer cylinder 14 is fixed by press-fitting inside the collar 6 of the suspension member 2 having a similar shape.
[0017]
The rubber elastic body 16 is fixed to both the outer peripheral surface of the inner cylinder 12 and the inner peripheral surface of the outer cylinder 14 by vulcanization bonding means. The rubber elastic body 16 is also interposed between the flange 20 of the inner cylinder 12 and the flange 24 of the outer cylinder 14, and the outer cylinder 14 with respect to the inner cylinder 12 by both flanges 20, 24 and the rubber 16a interposed therebetween. It acts as a stopper to limit the axial displacement of the. The rubber elastic body 16 is molded behind the flange 20 of the inner cylinder 12 by the stopper rubber 16 a, and the outer periphery of the flange 20 is surrounded by the rubber elastic body 16.
[0018]
As shown in FIGS. 1 and 2, the flange 20 of the inner cylinder 12 is provided with a non-fastening surface portion 28 dropped into the peripheral edge portion of the fastening surface 18 to the vehicle body panel 1 via a step portion 26. The non-fastening surface portion 28 is a surface that surrounds the outer periphery of the fastening surface 18 perpendicular to the axial direction of the inner cylinder 12 over the entire circumference, and is an annular shape that is one step lower than the fastening surface 18 and arranged parallel to the fastening surface 18. It is a surface part. Accordingly, as shown in FIG. 1, the non-fastening surface portion 28 is in a non-contact state with the surface of the vehicle body panel 1 in a state where the inner cylinder 12 is fixed to the vehicle body panel 1, and is opposed to the surface through a slight gap. Arranged.
[0019]
The vibration isolating bush 10 is manufactured by setting the inner cylinder 12 and the outer cylinder 14 in a mold 50 and vulcanizing and molding a rubber elastic body 16 therebetween.
[0020]
For vulcanization molding, as shown in FIG. 3, one mold 52 that can receive one end including the flange 20 of the inner cylinder 12, another mold 54 that receives the other end of the inner cylinder 12, and the outer cylinder 14 between them. A mold 50 composed of upper and lower intermediate molds 56 and 58 for fixing the outer periphery of the mold is used.
[0021]
On the other hand, the mold 52 is provided with a recess 60 that receives one end including the flange 20 and the insertion portion 22 of the inner cylinder 12, and the peripheral surface of the stopper rubber 16 a is molded on the side surface of the recess 60. Yes. The other mold 54 is provided with a protrusion 62 that is inserted into the outer cylinder 14 and molds the end surface of the rubber elastic body 16.
[0022]
On the other hand, the concave portion 60 of the mold 52 is provided with a pressing surface portion 64 that presses the non-fastening surface portion 28 of the flange 20 of the inner cylinder 12. The pressing surface portion 64 is provided so as to be pressed against the non-fastening surface portion 28 on the outer periphery rather than the fastening surface 18 when the mold is closed. Then, by pressing the pressing surface portion 64 against the non-fastening surface portion 28 in this way, rubber can be prevented from entering the fastening surface 18 on the inside.
[0023]
Specifically, as shown in FIG. 4, it is preferable that the height a of the pressing surface portion 64 is set to be slightly larger than the step b between the fastening surface 18 and the non-fastening surface portion 28. It can be effectively pressed against the non-fastening surface portion 28. Further, it is preferable to secure a slight gap g between the inner peripheral edge of the pressing surface portion 64 and the stepped portion 26.
[0024]
According to the present embodiment configured as described above, in the inner cylinder 12 having the flange 20 on which the stopper rubber 16a is molded on the surface opposite to the fastening surface 18, a stepped portion is formed on the peripheral edge portion of the flange fastening surface 18 of the inner cylinder 12. 26, a non-fastening surface portion 28 is provided, and the non-fastening surface portion 28 is used as a seal surface portion to press the pressing surface portion 64 of the mold 50 against the non-fastening surface portion 28 at the time of vulcanization molding of the rubber elastic body 16. Intrusion of rubber into the fastening surface 18 can be prevented. In addition, since the sealing surface portion pressed by the mold 50 at the time of vulcanization molding is the non-fastening surface portion 28 as described above, even if surface roughening occurs due to pressing, the fastening surface 18 is not roughened. A sufficient fastening with 1 is possible.
[0025]
FIG. 5 shows a modification of the pressing surface portion 64 in the above embodiment. In this example, the pressing surface portion 64 is provided with a sealing projection 70 having a substantially triangular cross section extending in the circumferential direction. The non-fastening surface portion 28 is pressed into the bite. The cross-sectional shape of the seal projection 70 is not limited to a triangular shape, and may be a semicircular shape or a rectangular shape.
[0026]
When the protrusion 70 is bitten in this way, the pressed surface is uneven, but the non-fastening surface portion 28 does not affect the fastening with the vehicle body panel 1. In this way, by encroaching the sealing protrusions 70, it is possible to more effectively block rubber from entering the fastening surface 18 and prevent rubber burrs on the fastening surface 18 even better.
[0027]
In addition, in the said embodiment, although the inner cylinder 12 which has the flange 20 for fastening only to one end part was demonstrated, in this invention, it is not limited to one end part, A flange is provided in both end parts, and the same seal | sticker A configuration can also be adopted. Further, in the above embodiment, the case where the rubber elastic body 16 is fixed to both the inner cylinder 12 and the outer cylinder 14 by vulcanization molding has been described. It can be similarly applied to a type of anti-vibration bushing that is fixed by vulcanization molding only and used by pressing a rubber elastic body into a collar of a support member such as a suspension member.
[0028]
【The invention's effect】
According to the present invention, since the non-fastening surface portion dropped through the step portion is provided at the peripheral portion of the fastening surface of the inner cylinder end portion, the non-fastening surface portion is fastened to the fastening surface at the time of vulcanization molding of the rubber elastic body. It is possible to act as a seal surface portion that blocks the intrusion of rubber into the rubber, and it is possible to effectively prevent rubber burrs on the fastening surface.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an anti-vibration bush according to an embodiment of the present invention in a vehicle assembled state.
FIG. 2 is a plan view of the vibration isolating bush.
FIG. 3 is a cross-sectional view of the vibration isolating bush during vulcanization molding.
4 is an enlarged cross-sectional view of a main part of FIG. 3;
FIG. 5 is an enlarged cross-sectional view of a main part at the time of vulcanization molding in another embodiment.
FIG. 6 is a cross-sectional view of a conventional anti-vibration bush during vulcanization molding.
FIG. 7 is a cross-sectional view of another conventional anti-vibration bush during vulcanization molding.
[Explanation of symbols]
10 ... Vibration isolating bush 12 ... Inner cylinder 14 ... Outer cylinder 16 ... Rubber elastic body 18 ... Fastening surface 20 ... Flange 26 ... Stepped portion 28 ... Non-fastening surface portion 50 ... Mold 64 ... Press surface

Claims (2)

A bushing for vibration-proof connection between the first member and the second member, wherein a rubber elastic body is fixed to the outer periphery of the inner cylinder attached to the first member by vulcanization molding, and the end of the inner cylinder A method of manufacturing a vibration-proof bushing in which a flange having a fastening surface to the first member is provided in a portion, and a non-fastening surface portion is provided on a peripheral portion of the fastening surface via a stepped portion;
When the rubber elastic body is vulcanized and molded, a pressing surface portion provided in a mold is pressed against the non-fastening surface portion, thereby preventing rubber from entering the fastening surface inside thereof. Bush manufacturing method. Wherein the pressing surface provided with a sealing projection extending in the circumferential direction, the manufacturing method of the vibration damping bush according to claim 1, wherein the pressing the projection on the non-fastening surface.

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