JPH06182814A - Insert member - Google Patents

Abstract

PURPOSE:To simply and inexpensively produce an insert member and to certainly prevent the creeping of a rubber material. CONSTITUTION:An insert member 1 is a cylindrical member and both ends 11,12 of the member 1 are gradually made thin by inclined surfaces 1a to be allowed to protrude in the axial direction of the member. The length L of the insert member is set so as to be slightly longer than the opposed interval of the surfaces of a mold and, at the time of mold clamping, both protruding end parts 11,12 come into contact with the surfaces of the mold to be pressed and deformed and the length L of the insert member is shortened to the length equal to the opposed interval and an injection closed space of a rubber material is demarcated and formed in the mold. Since it is unnecessary to accurately set the length of the insert member 1, the insert member is simply and inexpensively produced by forging.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an insert member,
In particular, the present invention relates to an insert member that can reliably prevent wraparound of rubber materials, resin materials and the like in a mold, and that is simple and inexpensive to manufacture.

[0002]

2. Description of the Related Art FIG. 6 shows a cylindrical vibration-proof bush, in which a vibration-proof rubber body 3 is joined between a thick small-diameter metal inner cylinder 1 and a thin large-diameter metal outer cylinder 2. In such a vibration-proof bush, the inner cylinder 1 and the outer cylinder 2 which are insert members are inserted into a mold (only the inner cylinder is shown in FIG. 7), and the upper mold 42 and the lower mold 41 are attached to the upper and lower end surfaces of the inner cylinder. A closed space S is formed outside the inner cylinder 1 by intimately adhering to it, and a rubber material is injected into the space S from a rubber material injection port 43.

In this case, even if the thin outer cylinder 2 is made longer than the facing interval of the mold surfaces, the thin outer cylinder 2 is curved and deformed at the time of contact to absorb the error, but the thick inner cylinder 1 has high rigidity. The mold surface is damaged. On the other hand, when the length of the inner cylinder 1 is shortened, a gap is created between the end surface of the inner cylinder 1 and the mold surface, and the rubber material passes through this gap and flows into the inner cylinder 1 which is the non-molded surface of the rubber body. Therefore, the length of the inner cylinder 1 must be accurately matched with the facing distance of the mold. Further, even if the end surface of the inner cylinder 1 is flawed, it causes a gap.

[0004]

Therefore, the inner cylinder 1 needs to be manufactured by cutting the pipe material accurately and carefully so as not to damage it, and by pressing the pipe surface against the end surface of the pipe. When it deforms slightly, it becomes a burr and bites into the positioning pin 44 that is inserted into the inner cylinder 1. Therefore, it is necessary to chamfer the inner peripheral portion of the end face (G in the figure), which is a labor for manufacturing. And increased costs.

An object of the present invention is to solve the above problems, and an object thereof is to provide an insert member which is simple and inexpensive to manufacture, and which can surely prevent the rubber material from wrapping around.

[0006]

The structure of the present invention will be described. The insert member 1 has a tubular shape, and both end portions 11 and 12 are formed.
Is gradually thinned by the inclined surface 1a so as to project in the axial direction, and the tube length L thereof is set to be slightly longer than the facing interval of the mold surfaces so that both end portions 11 project at the time of mold clamping.
12 is brought into contact with the surface of the mold to be deformed by pressing, so that the cylinder length L is shortened to a length equal to the facing interval and a closed space S for injecting a rubber material is defined in the mold.

[0007]

In the above structure, since the tube length of the insert member 1 may be set to be slightly longer than the facing interval of the molds, it is not necessary to ensure the dimensions accurately. Therefore, instead of the conventional cutting of the pipe material, forging or the like from the round bar can be easily and inexpensively manufactured.

The closed rubber material injection space S is surely defined and formed in the mold by the insert member end portions 11 and 12 which are brought into contact with the mold surface and are deformed by pressing. Since some flaws are also eliminated during the above-mentioned pressure deformation, excessively careful manufacturing is not required.

Further, although burrs are generated along with the deformation, the burrs are generated along the inclined surface 1a and therefore do not interfere with other members.

[0010]

[Embodiment 1] FIG. 1 shows an inner cylinder 1 which is an insert member of the vibration-proof bush described above. The inner cylinder 1 is a thick metal cylindrical body, and the upper and lower end surfaces thereof are inclined surfaces 1a that incline downward. Then, both ends of the inner cylinder 1 are gradually thinned toward the outer peripheral edge and protrude vertically with triangular cross sections respectively, and the cylinder length L between the protruding ends is made slightly longer than the facing interval of the molding die. There is.

When the inner cylinder 1 is inserted into the mold and clamped, for example, at the lower end 11, as shown in FIG. 2, a thin projecting end having a triangular cross section is kept within a certain range from the top with a relatively small pressure. It is pressed and deformed so as to come into close contact with the surface of the die 41 and form a closed space S outside the cylinder.

Thus, the rubber material injection space S can be reliably formed without damaging the surface of the mold 41 by the inner cylinder 1 molded with an appropriate length slightly longer than the facing distance of the mold.

The burr at the time of deformation is inclined from the outer periphery to the inclined surface 1
Since it occurs along a, it does not interfere with the positioning pin inserted in the cylinder.

The inner cylinder 1 can be easily and inexpensively manufactured by forging, and the flaws produced at the end face at the time of manufacturing are eliminated at the time of press deformation, so that excessive caution in manufacturing is not required.

[0015]

[Embodiment 2] The present invention is not limited to the inner cylinder of the vibration-proof bush, but can be applied to the ring weight 5 of the damper pulley as shown in FIG. In the figure, a ring weight 5 as an insert member has a belt suspension groove 53 on the outer circumference, a rubber layer 6 of a constant thickness is formed on the inner circumference thereof, and a tubular holding plate 7 joined to the inner circumference thereof. It is fitted and fixed to a metal boss (not shown).

Both end surfaces of the ring weight 5 are inclined surfaces 5a which are inclined downward toward the outside.
As shown in FIG. 4, one of the inner peripheral edges of the reference numerals 1, 52 projects in a substantially trapezoidal cross section that gradually becomes thinner.

However, when the mold is clamped at the time of injection molding of the rubber layer, the projecting end of the end portion 51 is pressed and deformed as shown by the chain line in the figure, and the same effect as the above-mentioned embodiment is obtained.

[0018]

Third Embodiment As shown in FIG. 5, inclined surfaces 5a and 5b are formed on the inner and outer circumferences of the ring weight end portion 51, and the projecting end has a mountain-shaped cross section, as shown by the chain line in the figure. Even if it is pressed and deformed, the same effect as that of each of the above embodiments can be obtained.

[0019]

As described above, the insert member of the present invention can surely partition and form the closed rubber material injection space in the mold, and is simple and inexpensive to manufacture.

[Brief description of drawings]

FIG. 1 is an overall sectional view of an inner cylinder of a vibration isolation bush.

FIG. 2 is an enlarged cross-sectional view of an end portion of an inner cylinder.

FIG. 3 is an overall sectional view of a ring weight of a damper pulley.

FIG. 4 is an enlarged cross-sectional view of an end portion of the ring weight, which is indicated by A in FIG.
FIG.

FIG. 5 is an enlarged sectional view of an end portion of the ring weight.

FIG. 6 is an overall sectional view of a conventional vibration damping bush.

FIG. 7 is a cross-sectional view showing a state in which a conventional inner cylinder is inserted into a mold.

[Explanation of symbols]

 1 Inner Cylinder (Insert Member) 1a Inclined Surface 11,12 End 5 Ring Weight (Insert Member) 5a Inclined Surface 51,52 End

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B29L 23:22 4F

Claims (1)

[Claims] 1. A cylindrical body, both ends of which are gradually thinned by inclined surfaces so as to project in the axial direction, and the length of the tube is set to be slightly longer than the facing interval of the mold surfaces so that it projects during mold clamping. The both ends of the cylinder abut on the surface of the mold and are deformed by pressing, so that the cylinder length is shortened to a length equal to the facing interval and a closed space for injecting a rubber material, a resin material or the like is formed in the mold. An insert member characterized by being.