JPH0133324B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Application of the Invention] This invention relates to a seal lip portion made of an elastic material such as rubber on the inner and outer periphery of a metal L-shaped reinforcing ring, such as an oil seal, a valve stem seal, a dust seal, etc. The present invention also relates to a method and apparatus for manufacturing a seal having a mounting fitting portion formed thereon, and particularly to a method and apparatus for molding a seal lip portion and a mounting fitting portion from different materials.

"Prior Art" Generally, this type of seal has a seal lip formed on the inner circumference of an L-shaped reinforcing tube, and a mounting fitting on the outer circumference for fitting into a fitting hole in a fixing part that fixes the seal. However, in conventional seals, this seal lip part and mounting fitting part are integrally molded from one type of elastic material such as rubber.
Therefore, in the molding process, a method is adopted in which a molding material such as rubber is sequentially filled into the molding spaces of the seal lip portion and the attachment fitting portion that communicate with each other.

"Problems to be Solved by the Invention" By the way, in this type of seal, the seal part is always in contact with the rotating shaft or sliding shaft to be sealed, so it has poor wear resistance, heat resistance, oil resistance, etc. It is necessary to use excellent, high-quality, and expensive materials, but the mounting fitting part only needs to have enough elasticity to fit tightly into the fitting hole, and the sealing lip part requires more expensive material. There's no need to.

Therefore, in the conventional method of integrally molding the seal lip part and the mounting fitting part, the same expensive material as the seal lip part has to be used for the mounting fitting part, making the seal unnecessarily expensive. Become something.

"Means for Solving the Problems" In order to solve the above-mentioned conventional problems, the present invention has the following features:
The intermediate portion between the inner and outer peripheries of the reinforcing ring is pressed by a pressing portion, which is provided opposite to the opposing surfaces of the molding molds and which is supported by an elastic member at least on one side and is movable back and forth in opposing directions. The molding spaces of the seal lip part and the mounting fitting part, which are formed on the inside and outside of the clamping part when the mold is pressed against the mold, are filled with elastic materials of different compositions from separate filling injection parts. By molding it, the reinforcing ring is easily and reliably held in the clamping part, while the molding space of the seal lip part and the mounting fitting part is hermetically partitioned. This paper proposes a seal manufacturing method and apparatus that makes it possible to fill each part with inexpensive materials and mold them simultaneously as separate parts, thereby reducing the overall cost. .

``Embodiment'' Below, an explanation will be given of an embodiment of this invention shown in the drawings. Figures 1 to 4 show an example of the configuration and operation of a molding device used in this invention, and its basic configuration is It consists of a receiving form and a pressing form that can be pressed against and separated from above the receiving form, and is made of an elastic material on the inner periphery of the metal reinforcing ring H having an L-shaped cross section as shown in Fig. 2. It is configured to form a seal having a seal lip portion S and a mounting fitting portion K made of a different type of elastic material on the outer periphery.

The receiving formwork includes a fixed mold 2 fixed to the base 1,
It is composed of an annular sliding mold 4 that is fitted into a central circular space 3 so as to be slidable up and down.
is applied an upward elastic force by a plurality of compression springs 5 installed between its bottom and the base 1, and is held at the upper limit position away from the base 1 in states other than pressure molding.

A clamping part 6 made of an annular protrusion is formed on the outer periphery of the upper end of the sliding mold 4. The upper end of the clamping part 6 has a flat surface, and the outer peripheral surface is approximately vertical. A reinforcing ring H can be loaded onto the outer peripheral surface of the clamping part 6, and a mold surface 7 for molding the shape of the outer peripheral part of the seal lip part S is formed on the inner peripheral surface of the clamping part 6.

On the circumferential surface of the circular space 3 of the fixed mold 2, a molding surface 8 for molding the outer peripheral part of the mounting fitting part K is formed at the upper end, and a locking part 9 of the sliding mold 4 is formed at the lower end. A stopper 10 is provided for locking and regulating the upper limit position, and a recess 11 provided above the stopper 10 is in pressure contact with the outer periphery of the sliding mold 4 so that the fixed mold 2 and the sliding mold 4 can be connected to each other. A seal ring 12 is attached to seal the gap.

On the other hand, the press mold frame includes a lower press mold 13 that is located above the pressure contact part 6 of the sliding frame 4 and the fixed mold 2 on the outside and moves up and down, and a lower press mold 13 that is located above the press mold 13 and moves up and down. It is composed of an upper pressing mold 14.

The lower pressing mold 13 has a circular space 15 in its center, and the upper peripheral surface of this circular space 15 is formed into an inclined inward downward slope 16, and the lower end peripheral surface is filled with a molding material such as rubber. A loading part 17 consisting of an annular protruding step part to be held is formed, and a pressure contact part 16 of the sliding mold 4 is formed at the corner of the lower end of the loading part 17.
A press-contact portion 18 consisting of an annular protrusion is formed opposite to the press-contact portion 18, and the press-contact portion 18 has a downwardly projecting lower surface forming a flat surface and an inner peripheral portion protruding toward the circular space 15 side.

The lower pressing mold 13 is provided with a concave loading portion 19 into which an elastic material such as rubber is loaded from above, and an inlet passage 20 that communicates with this and penetrates the bottom surface of the pressing mold 13. 20, when the lower pressing die 13 is pressed against the fixed die 2, both dies 2,
The molding space 21 of the mounting fitting part K formed between 13
It communicates with an inflow path 22 to the inlet.

The upper pressing mold 14 is provided with a convex portion 23 inserted into the circular space 15 of the lower pressing mold 13 at the center of its lower surface, and a material pressurizing portion inserted into the loading portion 19 of the lower pressing mold 14 on the lower surface around the convex portion 23 . A section 24 is provided, and the material pressurizing section 24 comes into close contact with the lower pressing mold 13 when the material pressurizing section 24 is lowered to the lower limit position within the loading section 19 .

The convex portion 23 of the upper pressing mold 14 is provided with a joint surface 25 at its lower part that is in close contact with the upper end of the sliding mold 4, and the circumferential surface above this joint surface 25 is provided with the inner surface of the seal lip portion S of the seal. A molding surface 26 for molding the shape of the peripheral surface is provided, and when the joint surface 25 comes into pressure contact with the upper end of the sliding mold 4, it forms a molding space 27 of the seal lip portion S together with the molding surface 7 of the sliding mold 4. ing.

Further, on the circumferential surface of the convex portion 23 on the molding surface 26, an annular material pressing portion 28 having a hook-shaped cross section is provided. When descending against the lower press type 1
A molding material inflow channel 29 with a predetermined gap is formed between the molding material inflow channel 29 and the loading section 17 of No. 27 is filled.

Further, an upper pressing die 1 is provided on the upper circumferential surface of the convex portion 23.
4 is pressed against the lower pressing die 13, the circular space 15
An inclined surface 30 is provided which closely fits the inclined peripheral surface of the material pressing section 24, and an air vent chamber 31 is formed at the bottom between the upper end of the inclined surface 30 and the upper end of the peripheral surface of the material pressurizing section 24.

When manufacturing seals using the above equipment,
First, the pushing formwork is lifted above the receiving formwork, and a reinforcing ring H is fitted around the clamping part 6 of the sliding die 4 protruding to the upper limit position to support it in the middle of its horizontal part. In this state, the lower pressing mold 13 is lowered and its pressing portion 18 is pressed against the middle of the horizontal portion of the reinforcing ring H. As a result, the horizontal part of the reinforcing ring H receives the weight of the lower pressing die 13 from above and below and the elastic force of the spring 5 of the sliding die 4, and is clamped and clamped in a sealed manner by the clamping parts 6 and 17. become.

Then, a predetermined amount of the masticated elastic material G mixed for the seal lip S is loaded into the loading part 17 of the lower pressing die 13, and the loading part 19 is provided with appropriate elasticity and strength as the mounting fitting part K. A predetermined amount of another relatively inexpensive molded elastic material G' is loaded. (3rd
(Figure) Next, the upper pressing die 14 is lowered and the lower pressing die 13 is lowered while pressing the materials G and G' with the material pressing parts 24 and 28. At this point, the sliding die 4 that is in contact with the reinforcing ring H is lowered. Then, the upper pressing mold 1
4, the material G' pressurized by the material pressurizing part 24 gradually flows into the molding space 21 through the injection port 20 and the inflow path 22, and is filled by the material pressurizing part 28. The pressurized material G gradually flows into and fills the molding space 27 through the inflow path 29, and when the upper pressing mold 14 reaches the lower limit position, the receiving mold frame and the pressing mold frame are completely combined. Materials G and G' are densely filled into molding spaces 21 and 27, respectively, which are precisely formed into a predetermined shape. (Fig. 4) When the molding spaces 21 and 27 are filled with different materials G and G' separately in this way,
The molding spaces 21 and 27 are hermetically partitioned by the clamping parts 6 and 17 that are constantly in pressure contact with the middle of the horizontal part of the reinforcing ring H to prevent the materials G and G' from mixing with each other. A seal lip portion S and a mounting fitting portion K made of separate materials are independently molded on the inner and outer peripheral portions of the reinforcing ring H, respectively.

After molding, when the pressing molds 13 and 14 are raised, the sliding mold 4 is automatically raised by the elasticity of the spring 5, and the seal molded at its upper end protrudes (Fig. 5).
This is taken out and surrounding burrs are cut off to create a complete product. (Fig. 2) "Effects of the Invention" As described above, according to the present invention, at least one side of the molds provided opposite to the opposing surfaces of the molds that are in contact with each other in a separable manner is supported by the elastic member so as to move in the opposite direction. The clamping part, which can move forward and backward, makes it possible to reliably clamp the intermediate part between the inner and outer circumferential parts of the reinforcing ring from the front and back from the beginning of the press-welding operation of both molds. The molding spaces of the seal lip part and the mounting fitting part formed on the inner and outer peripheral sides of the reinforcing ring are partitioned into separate molding spaces, and molded elastic materials of different compositions can be filled and molded separately without mixing them into separate molding spaces. can do.

Therefore, in addition to molding the seal lip part using an expensive material that satisfies various conditions such as abrasion resistance and heat resistance required for the seal lip part, it is also necessary to create a mounting fitting part that does not require as many conditions as the seal lip part. It can be molded using inexpensive materials, and the overall cost of the sealing member can be reduced.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of the main part of a molding apparatus according to the present invention, FIG. 2 is a partial vertical cross-sectional view showing an example of the position of a seal member molded according to the present invention,
The drawings and FIG. 5 are partial vertical cross-sectional views sequentially showing the molding process. 2... Fixed type, 4... Sliding type, 5... Compression spring, 6... Pressing part, 7... Molding surface, 8... Molding surface, 13... Lower pressing mold, 14... Upper pressing type,
17... Material loading section, 18... Pressing section, 19...
Material loading section, 21...Molding space, 26...Molding surface, 27...Molding space, H...Reinforcement ring, S...Seal lip part, K...Mounting fitting part, G, G...Molding material.

Claims (1)

[Scope of Claims] 1. In a method for manufacturing a seal having an elastic material sealing portion and a mounting fitting portion on the inner and outer peripheral portions of a reinforcing ring, a method for manufacturing a seal having a seal portion made of an elastic material and a mounting fitting portion on the inner and outer peripheral portions of the reinforcing ring, wherein An intermediate portion between the inner and outer peripheries of the reinforcing ring is clamped between clamping parts, at least one of which is supported by an elastic member and is movable in opposite directions. A method of manufacturing a seal, comprising filling molded elastic materials of different compositions into the molding spaces of the seal lip portion and the attachment fitting portion, which are formed on the inner and outer peripheral sides of the reinforcing ring. 2. In a seal manufacturing apparatus that has an elastic material sealing part and an attachment fitting part on the inner and outer peripheral parts of a reinforcing ring, the inner and outer peripheral parts of the reinforcing ring are placed on the opposing surfaces of molds that are in contact with and can be separated from each other by pressure. a clamping part which is provided facing each other so that the intermediate part thereof can be clamped by clamping, and at least one of which is supported by an elastic member and can move forward and backward in opposite directions; and a molding surface provided on each mold so as to form a molding space for the seal lip part and the attachment fitting part on the outside, respectively, and a filling injection part for separately filling each molding space with a molded elastic material. A seal manufacturing device characterized by: