JPH0743547Y2 - Sealing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a pressure-resistant sealing device including a rubber-like elastic seal lip and a resin ring for backing up the seal lip.

(Prior Art) As a conventional sealing device of this type, for example, there is one as shown in FIG. That is, this sealing device includes a seal body 100 having a first seal lip 101 made of a rubber-like elastic material.
And a resin ring 103 of a lip type having a resin seal lip 102 extending along the first seal lip 101 are integrally assembled. Such a sealing device has heretofore been made by integrally molding by inserting the resin ring 103 into a mold when vulcanizing and molding the seal body 100.

At that time, since the reinforcing ring 104 is embedded in the seal body 100, the reinforcing ring 104 and the resin ring 103 are superposed and inserted into the mold, and the rubber material as a molding material is pressure-heated to be integrated. It is designed to be molded.

(Problems to be Solved by the Invention) However, in the case of the above-mentioned conventional technique, when the dust lip 105 as the second seal lip made of a rubber-like elastic body is provided on the atmosphere side of the resin seal lip 102, the reinforcing ring 1
The flow of the molding material was obstructed by 04 and the resin ring 103, and there was a risk of defective molding at the dust lip 105.

Further, when the resin ring 103 is put into the mold, the resin ring 103 cannot be positioned due to the gap 106 between the resin ring 103 and the reinforcing ring 104, and therefore, be careful when inserting the resin ring. There was a problem that workability was poor because it had to be set to.

The present invention was made in order to solve the above-mentioned problems of the prior art.
(EN) Provided is a sealing device which improves the flow of a molding material to a second seal lip made of a rubber-like elastic body located on the atmosphere side of a reinforcing ring, and can reliably position a resin ring, thereby improving moldability. Is to try.

(Means for Solving the Problem) In order to achieve the above object, in the present invention, a seal body having a first seal lip made of a rubber-like elastic body supports a side surface of the seal lip on the atmosphere side. A resin ring having a resin seal lip is assembled, and a reinforcing ring for supporting the atmosphere side surface of the resin seal lip is further provided. The reinforcing ring has a radial portion and is made of a rubber-like elastic second seal lip. A sealing device integrally provided with the first seal lip and the resin seal lip by vulcanization molding, wherein the reinforcing ring has a plurality of holes through which a molding material passes during vulcanization molding of the rubber-like elastic body, It is characterized in that a support portion for radially positioning the resin ring is provided at the hole edge of this hole.

(Operation) In the sealing device configured as described above, while supporting the outer diameter end of the resin ring by the outer diameter support portion of the reinforcing ring during vulcanization molding,
The second sealing lip is molded by flowing molding material through the hole to the opposite side of the reinforcing ring.

(Example) Below, this invention is demonstrated based on the Example shown in figure. In FIG. 1 showing a sealing device according to an embodiment of the present invention, reference numeral 1 denotes the entire sealing device, which is made of a rubber-like elastic body.
The seal main body 2 includes a seal lip 8 and a resin ring 3 that backs up the first seal lip 8.

The seal body 2 is an outer peripheral rubber type oil seal type, and includes an outer tubular portion 5 fitted to the inner periphery of the housing H, and a lip support portion 6 extending inward in the radial direction from the atmospheric side end edge of the outer tubular portion 5.
And a first seal lip 8 that extends from the lip support portion 6 toward the sealed fluid 0 side and has a lip tip 7 in sliding contact with the outer peripheral surface of the rotating shaft S to form a first seal portion. The outer cylinder portion 5 and the lip support portion 6 of the seal body 2 are formed by integrally baking a rubber-like elastic body with the reinforcing ring 4 made of metal having an L-shaped cross section for reinforcement as a core. The reinforcing ring 8 has a cylindrical portion 9 embedded in the outer cylindrical portion 5.
And a flange portion 10 embedded in the lip support portion 6.

A dust lip 13 as a second seal lip is provided at the inner diameter end of the flange portion 10 of the reinforcing ring 4.

On the other hand, the resin ring 3 is, for example, a fluorocarbon resin such as PTFE (tetrafluoroethylene resin) or another resin-made ring-shaped member having low friction and excellent wear resistance. The rubber-like elastic first seal lip 8 is provided with a resin seal lip 11 extending along the side surface on the atmosphere side. The inner peripheral surface of the resin seal lip 11 is in sliding contact with the rotating shaft S, and the sliding surface is provided with a spiral thread groove 12 that functions as a screw pump. Further, the tip of the resin seal lip 11 extends to the jaw of the lip tip 7 of the rubber seal lip 8 and supports almost the entire length of the first seal lip 8. The outer diameter side end portion 31 of the resin ring 3 is fixed by being sandwiched between the flange portion 10 of the reinforcing ring 4 and the base portion of the first seal lip 8.

As shown in FIG. 2, the flange portion 10 of the reinforcing ring 4 is provided with a plurality of holes 15 in four places in this embodiment, and through the holes 15, the sealed fluid side and the atmosphere side are provided. And are in communication.

Further, on the inner diameter side edge of the hole 15, an outer diameter support portion as a support portion protrudingly formed toward the axially sealed symmetrical fluid side.
16 are provided. The resin ring 3 is attached to the outer diameter support portion 16.
The resin ring 3 is positioned by abutting the outer diameter ends of the. The protruding width of the outer diameter support portion 16 is set to be approximately the thickness of the resin ring 3.

The sealing device having the above-described structure has a reinforcing ring 4 and a resin ring 3 in a mold.
Are inserted, and the rubber material G is pressed and heated to be integrally vulcanized and molded. This molding is performed by using a mold 20 as shown in FIG. 3, for example.

The mold 20 is composed of an upper mold 20A and a lower mold 20B, and a core 20C having a thread groove 20D on the outer circumference is inserted in the center of the lower mold 20B.

Thus, the rubber material that has been fluidized during the vulcanization process flows around to the back side of the reinforcing ring 4 through the hole 16 provided in the flange portion 10 of the reinforcing ring, and smoothly flows around to the dust lip forming portion. Therefore, the molding failure of the dust lip is prevented. Further, since the outer diameter end of the resin ring 3 is positioned in contact with the outer diameter support portion 16 of the reinforcing ring 4, the centering between the resin ring 3 and the seal body 2 is surely performed.

(Effects of the Invention) The present invention has the above-described configuration and operation, and provides a sealing device in which the first and second seal lips made of a rubber-like elastic body, the resin seal lip and the reinforcing ring are integrally formed by vulcanization molding. , By providing the outer diameter support portion for positioning the outer diameter of the resin ring on the hole edge of the hole provided in the radial portion of the reinforcing ring, the resin ring can be positioned easily and the resin ring can be positioned accurately. Can be formed by molding, and the concentricity does not vary from product to product.

Further, since the reinforcing ring is provided with a plurality of holes through which the molding material passes during molding of the rubber-like elastic body, the molding material flows smoothly during the molding of the rubber-like elastic body, and the cavity of the molding die is efficiently and quickly provided. The molding material can be filled.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a main part of a sealing device according to an embodiment of the present invention, and FIG. 2 shows the reinforcing ring of FIG. 1, and FIG.
Is a plan view, FIG. 2B is a sectional view taken along line BB of FIG.
FIG. 3 is a longitudinal sectional view of an essential part showing a molding state of the sealing device of FIG. 1, and FIG. 4 is a longitudinal sectional view of an essential part of a conventional sealing device. Explanation of reference numerals 1 ... Sealing device, 2 ... Seal body 3 ... Resin ring, 4 ... Reinforcing ring 5 ... Outer cylinder part, 6 ... Lip support part 7 ... Lip tip, 8 ... First seal Lip 9 …… Cylinder, 11 …… Resin seal lip 12 …… Screw groove 15 …… Hole, 16 …… Outer diameter support 20 …… Mold, 20A …… Upper mold 20B …… Lower mold, 20C… … Core 20D …… Screw groove H …… Housing, S …… Rotating shaft

Claims (1)

[Scope of utility model registration request] 1. A seal body having a first seal lip made of a rubber-like elastic body is assembled with a resin ring having a resin seal lip for supporting a side surface of the seal lip on the atmosphere side, and the atmosphere of the resin seal lip is further assembled. A reinforcing ring for supporting the side surface is provided, and the reinforcing ring has a radial portion, and a second seal lip made of a rubber-like elastic body is integrally formed with the first seal lip and the resin seal lip by vulcanization molding. In a sealing device provided with, a plurality of holes through which a molding material passes at the time of vulcanization molding of the rubber-like elastic body are provided in the reinforcing ring, and a supporting portion for radially positioning the resin ring at the hole edge of the hole. A sealing device comprising: