JPH0139541Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a mold for integrally molding a rubber seal body onto a hard retainer.

(Prior art and its problems) As shown in FIG. 6, a ring-shaped retainer mounting groove 3 is simply formed in the lower mold 1. That is, the retainer 10 is installed directly in the installation groove 3, and the retainer 10
A rubber seal main body 12 is molded into a rubber mold groove 11 by an upper mold 2.

However, if only the retainer mounting groove 3 is formed, the thickness dimension T of the retainer 10 (FIG. 5)
If there are variations in the retainer mounting groove 3.
When there is variation in the depth dimension H shown in FIG. 6 (in the case of a multi-cavity type groove), the following problems occur.

That is, when the thickness dimension T of the retainer 10 is larger than the depth dimension H of the retainer mounting groove 3, the upper surface 10a of the retainer 10 is crushed by the lower surface 2a of the upper die 2 due to the molding pressure of the press, and the retainer 10
will be damaged and you will not be able to obtain a good product.

The thickness dimension T of the retainer 10 is the retainer mounting groove 3.
is smaller than the depth dimension H, the molding pressure of the press is received by the upper surface 1a of the lower mold 1, and a gap (H-T) is created between the upper surface 10a of the retainer 10 and the lower surface 2a of the upper mold 2. . The rubber that has flowed out from the rubber mold groove 11 remains in this gap, producing a product as shown in FIG. Removing the excess rubber that has flowed out from the rubber mold groove 11 takes a lot of man-hours and is a cause of increased costs. Moreover, even after removing the retainer 10 as shown in FIG.
Variations occur in the dimension D (H-T) from the top surface 10a of the rubber seal body 12 to the top of the rubber seal body 12, making it impossible to obtain a product with high dimensional accuracy.

Note that resin molding molds with a structure in which the lower mold or the upper mold itself is biased by an elastic member, as in JP-A-59-26324, JP-A-52-90562, or JP-A-52-90563, are However, biasing the heavy mold itself makes the elastic device and the mold itself large and complex.

(Means for solving the problem) In order to solve the above problem, the present invention provides a
In a mold that includes a retainer positioning pin and an annular retainer mounting groove around the pin, a hard retainer is mounted in the retainer mounting groove, and a rubber seal body is molded in the annular rubber mold groove of the retainer by an upper die. , a telescopic annular metal urging means for pushing up the retainer toward the upper mold is provided on the bottom surface of the retainer mounting groove at a position corresponding to the annular rubber mold groove, and an annular spacer is provided between the retainer and the urging means. I am intervening.

(Example) In FIG. 1, a retainer positioning pin 5 projecting upward is formed in the center of the lower mold 1.
An annular retainer mounting groove 3 having an open upper surface is formed around the pin 5. A guide hole 6 is formed in the center of the upper mold 2, and the upper mold 2 is fitted onto the pin 5 so as to be slidable in the vertical direction. The lower surface 2a of the upper mold 2 has an annular relief groove 7 corresponding to the radially outer end of the retainer mounting groove 3, and an annular relief groove 8 corresponding to the radially inner end of the retainer mounting groove 3. is formed. An annular groove 9 for forming a lip is also formed.

An annular wave spring attachment groove 21 is formed in the bottom surface 3a of the retainer attachment groove 3, and a metal annular wave spring 22 as shown in FIG. 2 is attached to the spring attachment groove 21 as a biasing means. An annular spacer 23 is placed on the upper surface of the wave spring 22 as shown in FIG. 1, and the retainer 10 is placed on the spacer 23. The material of the spring 22 may be a common steel spring material.

The height dimension A (Fig. 3) of the spring 22 is A>H+
It is set to h-T-B. However, H is the depth dimension of the retainer mounting groove 3, h is the depth dimension of the spring mounting groove 21, T is the thickness dimension of the retainer 10, and B is the thickness dimension of the spacer 23. Further, the relationship of H≧T+B and the relationship of A>h are also conditions of this embodiment.

(Function) Place the annular spacer 23 on the wave spring 22,
Place the retainer 10 on the annular spacer 23,
An unvulcanized rubber material is put into the rubber mold groove 11, the upper die 2 is lowered, and the rubber seal body 12 is press-molded. That is, the seal body 12 is vulcanized and molded by applying high temperature and high pressure to the rubber material.

When the upper mold 2 is lowered, the lower surface 2a of the upper mold 2 first contacts the upper surface 10a of the retainer 10, and then further lowers while compressing the wave spring 22 and contacts the upper surface 1a of the lower mold 1. That is, even if there is some variation in the retainer thickness dimension T, it is adjusted by changing the amount of compression of the wave spring 22, and the lower surface 2a of the upper mold 2 always comes into contact with the upper surface 10a of the retainer 10 and the upper surface 1a of the lower mold 1. come into contact with

For example, when the retainer thickness dimension T is larger than the specified dimension, the amount of compression of the wave spring 22 increases,
No excessive force is applied to the upper surface 10a of the retainer 10. When the retainer thickness dimension T is smaller than the specified dimension, the amount of compression of the wave spring 22 is small, and the state of contact between the upper die lower surface 2a and the retainer upper surface 10a at an appropriate pressure is maintained.

Further, an annular wave spring 22 is arranged at a position corresponding to the position of the rubber mold groove 11 of the retainer 10,
Moreover, since the force is applied via the annular spacer 23, the force applied to the rubber seal body 12 during molding is balanced, pressure can be applied evenly over the entire circumference, and the rubber seal body 12 with uniform density can be molded. .

(Effects of the invention) As explained above, the present invention has the following features: (1) Even if there is some error in the retainer thickness dimension or the retainer mounting groove depth dimension, the upper mold 2 The lower surface 2a of is the retainer 1
0 reliably and without unreasonable load. As a result, the occurrence of defective products as shown in FIG. 7 is reduced, and the trouble of correcting defective products can be saved, and seal processing costs can be saved.

For example, if the thickness of the retainer is somewhat larger than the specified size, the amount of compression of the biasing means will increase, causing the upper surface of the retainer 10 to be pushed against the upper mold 2 by an unreasonable force.
It cannot be harmed by. Furthermore, if the retainer thickness dimension is somewhat smaller than the specified dimension, the compression amount of the biasing means is reduced, so that defective products as shown in FIG. 7 do not occur, and the finished dimensional accuracy of the seal body 12 relative to the retainer 10 is (Figure 5D) is high.

(2) Even if there is some dimensional error in the retainer 10 and the retainer mounting groove 3a, the seal body 12 can be finished to highly accurate dimensions by the action of the biasing means, so mold machining costs and retainer manufacturing costs can be reduced. can be kept low.

(3) The retainer 10, which is a component of the product, is biased by the wave spring 22 via the annular spacer 23, which is more effective than the conventional structure described above in which the mold itself, which is heavy and has a complicated structure, is biased. The structure itself is simple and can be miniaturized, eliminating the need for large-scale equipment.

(4) Since the metal wave spring 22 is disposed at a position corresponding to the position of the rubber mold groove 11 of the retainer 10 and is biased via the annular spacer 23, the retainer 10 is dented by the spring 22. There is no fear, the biasing force against the rubber seal body 12 during molding is balanced, pressure can be applied evenly over the entire circumference, and the rubber seal body 12 with uniform density can be molded.

By the way, the spring 22 is generally made of hard steel, and the retainer material is often made of soft metal such as aluminum in addition to mild steel.
If the retainer 2 is brought into direct contact with the retainer 10, it may be dented, and the annular spacer 23 prevents the occurrence of such dents.

(5) Also, since a metal elastic member is used,
Durability can be maintained during rubber seal molding work that is vulcanized at high temperature and high pressure.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of a mold to which the present invention is applied, Fig. 2 is a perspective view of the wave spring shown in Fig.
4 is a plan view of a combination seal manufactured by the mold of the present invention, FIG. 5 is a sectional view taken along the line V-V in FIG. 4, and FIG. 6 is a vertical sectional view of a conventional example. , 7 and 8 are longitudinal sectional views of defective combination seals. 1...Lower mold, 2...Upper mold, 3...
...Retainer mounting groove, 10...Retainer, 12...
Rubber seal body, 22... wave spring (metal biasing means).

Claims (1)

[Scope of utility model registration request] The lower mold 1 is provided with a retainer positioning pin 5 and an annular retainer mounting groove 3 around the pin 5, a hard retainer 10 is installed in the retainer mounting groove 3, and a hard retainer 10 is installed in the annular rubber mold groove 11 of the retainer 10. In the mold for molding the rubber seal body 12 using the upper mold 2, a retainer 1 is placed on the bottom surface of the retainer mounting groove 3 at a position corresponding to the annular rubber mold groove 11.
1. A mold structure characterized in that a telescopic annular metal urging means for pushing up the 0 toward the upper mold side is provided, and an annular spacer 23 is interposed between the retainer 10 and the urging means.