JPH08128484A - Vibration controller - Google Patents

Abstract

PURPOSE: To provide a vibration controller which can avert the formation of a creased part on a rubber elastic body, when a resin member is formed through the injection molding. CONSTITUTION: A vibration controller consists of an inside member 1 having a cylindrical outer peripheral surface, cylindrical rubber elastic body 2 which is integrally fixed with the outer peripheral surface of the inside member 1 and has a vacant place 21 which penetrates in the axial direction and extends in the circumferential direction, and an outside member 3 which is made of resin and fixed integrally with the outer peripheral surface of the rubber elastic body 2, and the inside member 1 and the rubber elastic body 2 are arranged in an injection molding body, and the outside member 3 is formed through the injection molding. On the rubber elastic body 2, a projection part 22 which projects into the vacant place 21, and is engaged with the molding surface when arranged in the injection molding mold, and regulates the shift of the rubber elastic body 2, when the molten resin which forms the outside member 3 is poured into the injection molding mold and flows on the surface of the rubber elastic body 2.

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 as, for example, an engine mount or a bush.

[0002]

2. Description of the Related Art Conventionally, as an anti-vibration device, an inner member having a cylindrical outer peripheral surface and attached to one mounting portion, and an inner member integrally fixed to the outer peripheral surface of the inner member, penetrating in the axial direction and surrounding the inner member. It is known that a cylindrical rubber elastic body having a space extending in the direction and a resin outer member integrally fixed to the outer peripheral surface of the rubber elastic body and attached to the other mounting portion are known. This anti-vibration device is configured to effectively damp the vibration generated between the inner member and the outer member by elastic deformation of the rubber elastic body, and the rubber elastic body has a predetermined shape with a void or the like. By forming the spring constant, the spring constant is set according to the desired damping frequency. Further, the outer member is made of resin to reduce the weight.

In order to manufacture this vibration isolator, first, a vulcanization molded article is produced by forming a rubber elastic body on the outer peripheral surface of the inner member by vulcanization molding and integrally fixing it. Then, the vulcanized molded product with the outer peripheral surface of the rubber elastic body coated with an adhesive is placed in the cavity of the injection molding die, and resin is injection-molded in the cavity in this state. The vibration isolator is completed by integrally fixing it to the outer peripheral surface of the body.

[0004]

By the way, in the case where the inner member and the rubber elastic body are arranged in the injection molding die and the outer member is formed by injection molding as in the above vibration isolator,
The molten resin forming the outer member is usually 2000 kg / cm
It is injected into the cavity from a gate formed on one side of the injection mold with a high injection pressure of about ² . At this time, the rubber elastic body extends along the flow of the molten resin due to the molten resin flowing on the surface of the rubber elastic body, and a wrinkled portion of the rubber elastic body is formed at a final reaching portion of the molten resin.
In particular, since the rubber elastic body is formed in a tubular shape having a void, such a wrinkled portion is likely to be formed when the rubber elastic body is thin. Therefore, when the molten resin is solidified and the outer member is formed while the wrinkled portion of the rubber elastic body is rolled up, the strength of the outer member is reduced or the set spring constant of the rubber elastic body is changed. A problem occurs.

It should be noted that the injection pressure of the molten resin should be 1/2 to the normal pressure.
By reducing it to 1/3, it is possible to avoid the generation of the wrinkled portion of the rubber elastic body, but in this case, it is not possible to secure the predetermined strength of the outer member. The present invention has been devised in view of the above problems, and it is an object of the present invention to provide a vibration damping device capable of avoiding formation of a wrinkled portion in a rubber elastic body when a resin member is formed by injection molding. It is an issue to be done.

[0006]

Means for Solving the Problems A first method for solving the above problems is described below.
The vibration damping device of the invention is an inner member having a cylindrical outer peripheral surface,
A cylindrical rubber elastic body integrally fixed to the outer peripheral surface of the inner member and having a cavity penetrating in the axial direction and extending in the circumferential direction, and a resin integrally fixed to the outer peripheral surface of the rubber elastic body. In a vibration-damping device comprising an outer member made of plastic, the inner member and the rubber elastic body are arranged in an injection molding die to form the outer member by injection molding, the rubber elastic body projects into the cavity. And, when the molten resin that engages with the mold surface when being arranged in the injection molding die and forms the outer member is injected into the injection molding die and flows on the surface of the rubber elastic body, the rubber elasticity It is characterized by having a protrusion that regulates the movement of the body.

A vibration isolator according to a second aspect of the invention is an inner member having a cylindrical outer peripheral surface, and a first member integrally fixed to the outer peripheral surface of the inner member so as to extend axially and extend circumferentially. A tubular first rubber elastic body having a void, and a tubular tubular intermediate member integrally fixed to the outer peripheral surface of the first rubber elastic body,
A cylindrical second member that is integrally fixed to the outer peripheral surface of the cylindrical intermediate member and that has a second cavity that extends axially and extends circumferentially.
A rubber elastic body and a resin outer member integrally fixed to the outer peripheral surface of the second rubber elastic body, and at least the inner member, the first rubber elastic body, and the second rubber elastic body are injection molded. In a vibration isolator that is arranged in a mold and forms the tubular intermediate member by injection molding, the first rubber elastic body and the second rubber elastic body project into the first cavity and the second cavity. Further, the molten resin that engages with the mold surface and forms the tubular intermediate member when placed in the injection molding die is injected into the injection molding die, and the first rubber elastic body and the second rubber elastic body. It is characterized in that it has a protrusion for restricting movement of the first rubber elastic body and the second rubber elastic body when flowing on the surface of the body.

[0008]

In the vibration isolator according to the first aspect of the invention, the rubber elastic body is provided with a protrusion that projects into the cavity and engages with the mold surface when placed in the injection molding mold. The protrusion restricts the movement of the rubber elastic body when the molten resin is injected into the injection mold and flows on the surface of the rubber elastic body when the outer member is formed by injection molding. Thereby, even if the molten resin is injected at a predetermined high injection pressure, it is possible to avoid the formation of the wrinkled portion on the rubber elastic body.

Further, in the vibration isolator of the second invention, the first rubber elastic body and the second rubber elastic body protrude into the first cavity and the second cavity and are disposed in the injection molding die. A protrusion is provided that engages the surface. When the molten resin forming at least the tubular intermediate member is injected into the injection mold by the projections and flows on the surfaces of the first rubber elastic body and the second rubber elastic body, the first rubber elastic body and the second rubber are formed. The elastic body is restricted from moving. Thereby, even if the molten resin is injected at a predetermined high injection pressure, it is possible to avoid the formation of the wrinkled portion on the rubber elastic body.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a side view of a vibration isolator according to this embodiment, FIG. 2 is a side view of a rubber elastic body of the vibration isolator according to this embodiment, and FIG. 3 is a sectional view taken along the line III-III in FIG. 4, and FIG. 4 is a sectional view taken along the line IV-IV in FIG.

The vibration isolator of this embodiment has a cylindrical inner member 1, a cylindrical rubber elastic body 2 integrally fixed to the outer peripheral surface of the inner member 1, and an outer peripheral surface of the rubber elastic body 2. The outer member 3 is made of resin and has a tubular portion 31 that is integrally fixed. The inner member 1 is formed of a metal into a cylindrical shape having a predetermined size, and has a cylindrical outer peripheral surface.

As shown in FIGS. 2 to 4, the rubber elastic body 2 is integrally fixed to the outer peripheral surface of the inner member 1 by vulcanization molding together with the inner member 1, and its cross-sectional outer peripheral shape is this vibration-proof. It is formed in an elliptic cylindrical shape whose major axis is in the direction of application of the load acting on the device. The rubber elastic body 2 has a pair of cavities 21 formed in a peripheral portion on the major axis side, the cavity 21 penetrating in the axial direction and extending in an arc shape along the circumferential direction and having a size of about half of the entire circumference. There is. Then, on the outer side of each cavity 21 of the rubber elastic body 2, there are four ridges (projections) 22 projecting into the cavity 21 toward the centripetal direction and extending in the axial direction, with four circumferentially spaced protrusions. They are provided one by one. This ridge 22
Engages with the mold surface when the rubber elastic body 2 is placed in the injection mold when the outer member 3 described later is formed by injection molding.

The outer member 3 is formed by placing the inner member 1 and the rubber elastic body 2 in an injection mold and performing injection molding, and is integrally fixed to the outer peripheral surface of the rubber elastic body 2. The outer member 3 includes a cylindrical portion 31 that covers the outer peripheral surface of the rubber elastic body 2 and a bracket portion 32 that is formed on one side of the outer peripheral surface of the cylindrical portion 31. Two nuts 34 are embedded in the bracket portion 32 so as to be screwed with a mounting bolt when the outer member 3 is mounted on a mounting partner member.

This vibration isolator is manufactured as follows. First, as shown in FIGS. 2 to 4, a tubular rubber elastic body 2 having a ridge portion 22 that projects into the cavity 21 and extends in the axial direction is formed by vulcanization molding together with the inner member 1,
A vulcanized molded product is produced in which the rubber elastic body 2 is integrally fixed to the outer peripheral surface of the inner member 1. Next, an adhesive is applied to the outer peripheral surface of the rubber elastic body 2 so that the protrusions 22 of the rubber elastic body 2 are engaged with the mold surface in the cavity of the injection molding die forming the outer member 3. A vulcanized molded article is placed, and molten resin is injected into the cavity in that state. At this time, even if the molten resin injected into the cavity flows on the surface of the rubber elastic body 2 and the rubber elastic body 3 is pressed along the flow by the injection pressure of the molten resin, the rubber elastic body 3 still has the mold surface. The movement is restricted by the protruding portion 22 that engages with. This allows
Even if the molten resin is injected at a predetermined high injection pressure, no wrinkled portion is formed on the rubber elastic body 2.

Thereafter, the molten resin solidifies,
The resin outer member 3 integrally fixed to the outer peripheral surface of the rubber elastic body 2 is formed, and the vibration damping device shown in FIG. 1 is completed.
When the vibration damping device of the present embodiment manufactured as described above is used as, for example, an engine mount, the inner member 1 is fitted and fixed to the mounting shaft on the engine side, and the outer member 3 is mounted on the mounting portion on the vehicle body side. It is mounted by a mounting bolt via the nut 34. Then, the vibration generated between the inner member 1 and the outer member 3 is effectively damped by the elastic deformation of the rubber elastic body 2.

As described above, according to the vibration isolator of this embodiment, the rubber elastic body 2 projects into the cavity 21 and engages with the die surface when placed in the injection molding die. Since the portion 22 is provided, when the outer member 3 is formed by injection molding, the movement of the rubber elastic body 3 is restricted by the molten resin injected into the injection molding die, so that the rubber member 3 has a predetermined height. Even if the molten resin is injected with the injection pressure, it is possible to avoid the formation of the wrinkled portion on the rubber elastic body 3. Therefore, the strength of the outer member 3 is reduced due to the formation of the wrinkled portion on the rubber elastic body 3, and the rubber elastic body 2
It is possible to prevent the occurrence of the problem that the set spring constant of 1 changes.

The ridge portion 2 provided on the rubber elastic body 2
In the present embodiment, four cavities 2 are provided in each vacant space 21, but the number, size (width, height), etc. of the lamellas 2 affect the set elastic constant of the rubber elastic body 2 and the like. It can be selected as appropriate in consideration of the above conditions. Further, the ridge portion 22 in the present embodiment is formed so as to continuously extend to both ends along the axial direction in the space 21, but a plurality of ridge portions partially formed in the axial direction. You may comprise by a part (protrusion).

(Embodiment 2) FIG. 5 is a sectional view of a vibration isolator according to this embodiment. The vibration damping device of this embodiment has a double bush structure, and includes a cylindrical inner member 5 and a tubular first rubber elastic body 6 integrally fixed to the outer peripheral surface of the inner member 5. A cylindrical intermediate member 7 made of resin integrally fixed to the outer peripheral surface of the first rubber elastic body 6, and a cylindrical second rubber elastic body integrally fixed to the outer peripheral surface of the cylindrical intermediate member 7. 8 and the second
It is composed of a resin outer member 9 having a tubular portion 91 integrally fixed to the outer peripheral surface of the rubber elastic body 8.

The inner member 5 is formed of a metal into a cylindrical shape having a predetermined size and has a cylindrical outer peripheral surface. The first rubber elastic body 6 is formed into a tubular shape by being vulcanized together with the inner member 5, and is integrally fixed to the outer peripheral surface of the inner member 1. In the peripheral portion of the first rubber elastic body 6,
A pair of first cavities 61 is provided which penetrates in the axial direction and extends in an arc shape along the circumferential direction. A ridge portion (projection) 62 is provided at the center of the outer side of each first cavity 61 of the first rubber elastic body 6 so as to project in the first cavity 61 in the centripetal direction and extend in the axial direction. ing. The ridge portion 62 engages with the mold surface when the first rubber elastic body 6 is placed in the injection molding mold when the cylindrical intermediate member 7 and the outer member 9 to be described later are formed by injection molding.

The tubular intermediate member 7 is formed by arranging the inner member 5, the first rubber elastic body 6 and the second rubber elastic body 8 in an injection molding die and performing injection molding, simultaneously with the formation of the outer member 9 described later. It is formed and is integrally fixed to the outer peripheral surface of the first rubber elastic body 6 and the inner peripheral surface of the second rubber elastic body 8. The second rubber elastic body 8 is formed into a tubular shape by vulcanization molding, and is integrally fixed to the outer peripheral surface of the tubular intermediate member 7 and the inner peripheral surface of the outer member 9. In the axially symmetrical portion of the second rubber elastic body 8, there is formed a pair of second hollows that penetrate the axial direction and extend in an arc shape along the circumferential direction and have a size of about 1/4 of the entire circumference. A pair of third cavities 85 penetrating in the axial direction and extending along the circumferential direction in a portion between the cavities 81 and the second cavities 81.
Is provided. Each second void 81 of the second rubber elastic body 8
In the center of the outer part of the second hollow 81
Two outer ridges (projections) 82 that project inward and extend in the axial direction are provided at intervals in the circumferential direction. Also,
Inner ridges (projections) 83 projecting in the second space 81 toward the centrifugal direction and extending in the axial direction are provided at the center of the inner side of each second space 81 of the second rubber elastic body 8. ing. The outer ridge 82 and the inner ridge 83 are such that the second rubber elastic body 8 is placed in the injection mold when the cylindrical intermediate member 7 and the outer member 9 described later are formed by injection molding. Sometimes it engages the mold surface.

The outer member 9 is formed simultaneously with the formation of the tubular intermediate member 7 by placing the inner member 5, the first rubber elastic body 6 and the second rubber elastic body 8 in an injection mold and performing injection molding. , Is integrally fixed to the outer peripheral surface of the second rubber elastic body 8. The outer member 9 includes a cylindrical portion 91 that covers the outer peripheral surface of the second rubber elastic body 8 and a bracket portion 92 that is formed on one side of the outer peripheral surface of the cylindrical portion 91. The bracket portion 92 has two nuts 94 embedded therein, which are screwed into mounting bolts when the outer member 9 is mounted on the mounting counterpart member.

This anti-vibration device is manufactured as follows. First, a tubular first rubber elastic body 6 having a first protruding portion 62 protruding in the first space 61 and extending in the axial direction is formed by vulcanization molding together with the inner member 5, and the outer periphery of the inner member 5 is formed. The first rubber elastic body 6 produces a vulcanized molded product on the surface, and the second cylindrical body has an outer protruding portion 82 and an inner protruding portion 83 that project into the second space 81 and extend in the axial direction. The rubber elastic body 8 is produced by vulcanization molding.

Next, the outer peripheral surface of the first rubber elastic body 6 and the second
Adhesive is applied to the inner and outer peripheral surfaces of the rubber elastic body 8 to form the cylindrical intermediate member 7 and the outer member 9 at the same time in the cavity of the injection molding die.
The inner member 5, the first rubber elastic body 6, and the second rubber elastic body 8 are arranged so that the outer protruding portion 82 and the inner protruding portion 83 of the rubber elastic body 8 engage with the mold surface of the injection molding die. Then, in that state, the molten resin is injected into the cavity. At this time, the molten resin injected into the cavity flows on the surfaces of the first rubber elastic body 6 and the second rubber elastic body 8, and the first rubber elastic body 6 and the second rubber elastic body 6
Even if the rubber elastic body 8 is pressed along the flow thereof by the injection pressure of the molten resin, the first rubber elastic body 6 and the second rubber elastic body 8 engage with the mold surface and the ridge portion 62 and the outer ridge portion. Movement is restricted by the portion 82 and the inward protruding portion 83. As a result, even if the molten resin is injected at a predetermined high injection pressure, the first rubber elastic body 6 and the second rubber elastic body 8 do not have wrinkled portions.

Thereafter, the molten resin solidifies,
A resinous tubular intermediate member 7 integrally fixed to the outer peripheral surface of the first rubber elastic body 6 and the inner peripheral surface of the second rubber elastic body 8 and the outer peripheral surface of the second rubber elastic body 8 integrally. The fixed outer member 9 made of resin is formed, and the vibration damping device shown in FIG. 5 is completed. When the vibration damping device of the present embodiment manufactured as described above is used as, for example, an engine mount, the inner member 5 is fitted and fixed to the mounting shaft on the engine side, and the outer member 9 is mounted on the mounting portion on the vehicle body side. It is mounted by a mounting bolt via the nut 94. Then, the vibration generated between the inner member 5 and the outer member 9 is effectively damped by the elastic deformation of the first rubber elastic body 6 and the second rubber elastic body 8.

As described above, according to the vibration isolator of this embodiment, the first rubber elastic body 6 and the second rubber elastic body 8 have the ridges 62, the outer ridges 82, and the inner ridges. Since the portion 83 is provided, when the cylindrical intermediate member 7 and the outer member 9 are formed by injection molding, the first rubber elastic body 6 and the second rubber elastic body 6 are formed by the molten resin injected into the injection molding die. It is possible to prevent the wrinkled portion from being formed in the first rubber elastic body 6 and the second rubber elastic body 8 even if the molten resin is injected at a predetermined high injection pressure by restricting the movement of the elastic body 8. You can Therefore, the strength of the tubular intermediate member 7 and the outer member 9 is reduced due to the formation of the wrinkled portions on the first rubber elastic body 6 and the second rubber elastic body 8, and the first rubber elastic body 6 and the second rubber elastic body 8 are reduced. It is possible to prevent the occurrence of the problem that the set spring constant of the elastic body 8 changes.

In the vibration isolator of this embodiment, the tubular intermediate member 7 and the outer member 9 are simultaneously formed of resin by injection molding, but in addition, only the tubular intermediate member 7 is injection molded. When the outer member 9 is formed first by injection molding and then the outer member 9 is formed by injection molding, or the outer member 9 is integrally formed with the second rubber elastic body 8 by injection molding to form the cylindrical intermediate member 7. Even when the cylindrical intermediate member 7 is formed by injection molding by arranging the integrated body and the integrated body of the inner member 5 and the first rubber elastic body 6 in the molding die, the ridge portion 62 and the outward protrusion By providing the ridge portion 82 and the inward ridge portion 83, the same effect as described above can be obtained.

[0027]

According to the vibration isolator of the first invention, the rubber elastic body is a molten resin which projects into the cavity and engages with the mold surface when the rubber elastic body is placed in the injection molding mold to form the outer member. Has a protrusion that restricts the movement of the rubber elastic body when it is injected into the injection molding die and flows on the surface of the rubber elastic body, so that the rubber elastic body is formed when the resin outer member is formed by injection molding. It is possible to avoid the formation of wrinkled parts on the body.

According to the vibration isolator of the second invention, the first
The rubber elastic body and the second rubber elastic body project into the first cavity and the second cavity and engage with the mold surface when placed in the injection molding die, and the molten resin forming the tubular intermediate member is A protrusion for restricting movement of the first rubber elastic body and the second rubber elastic body when injected into the injection mold and flowing on the surfaces of the first rubber elastic body and the second rubber elastic body. Therefore, it is possible to avoid the formation of the wrinkled portion on the first rubber elastic body and the second rubber elastic body when the resin-made tubular intermediate member is formed by injection molding.

[Brief description of drawings]

FIG. 1 is a side view of a vibration isolation device according to a first embodiment of the present invention.

FIG. 2 is a side view of the rubber elastic body of the vibration isolator according to the first exemplary embodiment of the present invention.

3 is a sectional view taken along the line III-III of FIG.

4 is a sectional view taken along the line IV-IV of FIG.

FIG. 5 is a sectional view of a vibration control device according to a second embodiment of the present invention.

[Explanation of symbols]

1, 5 ... Inner member 2 ... Rubber elastic body 21 ... Cavity 22 ... Ridge portion (projection) 3, 9 ... Outer member 6 ... First rubber elastic body 61 ... First cavity 62 ... Ridge portion (projection) 7 ... Cylindrical intermediate member 8 ... 2nd rubber elastic body 81 ... 2nd space 82 ... Outer ridge part (projection) 83 ... Inward ridge part (projection)

Claims (2)

[Claims] 1. An inner member having a cylindrical outer peripheral surface, and a cylindrical rubber elastic body integrally fixed to the outer peripheral surface of the inner member and having a cavity penetrating in the axial direction and extending in the circumferential direction. A resin outer member integrally fixed to the outer peripheral surface of the rubber elastic body, wherein the inner member and the rubber elastic body are arranged in an injection molding die to form the outer member by injection molding. In the vibration isolator, the rubber elastic body projects into the cavity and engages a mold surface when placed in the injection molding die, and molten resin forming the outer member enters the injection molding die. An anti-vibration device having a protrusion for restricting movement of the rubber elastic body when injected and flowing on the surface of the rubber elastic body. 2. An inner member having a cylindrical outer peripheral surface, and a cylindrical first member integrally fixed to the outer peripheral surface of the inner member and having a first cavity extending axially therethrough and extending circumferentially. A rubber elastic body, a resin-made cylindrical intermediate member integrally fixed to the outer peripheral surface of the first rubber elastic body, and an integrally fixed outer peripheral surface of the cylindrical intermediate member, and penetrates in the axial direction. And a cylindrical second having a second cavity extending in the circumferential direction
A rubber elastic body and a resin outer member integrally fixed to the outer peripheral surface of the second rubber elastic body, and at least the inner member, the first rubber elastic body, and the second member.
In a vibration damping device that arranges a rubber elastic body in an injection molding die to form the tubular intermediate member by injection molding, the first rubber elastic body and the second rubber elastic body include the first cavity and the first cavity. The molten resin that protrudes into the second cavity and engages with the mold surface when arranged in the injection molding die and forms the cylindrical intermediate member is injected into the injection molding die and the first rubber elastic body And an anti-vibration device having projections for restricting movement of the first rubber elastic body and the second rubber elastic body when flowing on the surface of the second rubber elastic body.