Method of manufacturing sealing apparatus and mold

• US 5,104,603 A
• Filed: 08/04/1989
• Issued: 04/14/1992
• Est. Priority Date: 08/05/1988
• Status: Expired due to Term

• Current Assignee: NOK Corporation
• Original Assignee: NOK Corporation
• Inventors: Saitoh, Takayuki
• Primary Examiner(s): Silbaugh, Jan H.
• Assistant Examiner(s): Eastley, Brian J.
• Application Number:
  US07/389,484
• Time in Patent Office: 984 Days
• Field of Search: 264/268, 264/249, 264/263, 264/266, 425/DIG. 47
• US Class Current: 264/249
• CPC Class Codes: B29C 2793/009 after shaping
• CPC Class Codes: B29C 43/021 characterised by the shape of the surface
• CPC Class Codes: B29C 43/027 having an axis of symmetry B29C43/102 takes precedence
• CPC Class Codes: B29C 43/18 incorporating preformed parts or layers, e.g. compression moulding around inserts or for coating articles B29C43/206 takes precedence
• CPC Class Codes: B29C 70/84 by moulding material on preformed parts to be joined joining plastic parts by moulding B29C65/70
• CPC Class Codes: B29D 99/0053 Producing sealings B29D99/0085 takes precedence
• CPC Class Codes: B29L 2031/26 Sealing devices, e.g. packaging for pistons or pipe joints
• CPC Class Codes: F16J 15/3216 supported in a direction parallel to the surfaces
• CPC Class Codes: F16J 15/3248 provided with casings or supports
• CPC Class Codes: Y10S 425/047 Seal ring

Abstract

A method of manufacturing a sealing apparatus. A rubber-like elastic material for forming a rubber-like elastic material sealing lip and a resin material for forming a resin sealing lip are placed within a mold for manufacturing a sealing apparatus by effecting vulcanization forming. The mold is clamped with contents placed therein, and the contents are pressurized and heated. During this process, a surface of the resin material is pressed by the forming pressure of the fluidized rubber-like elastic material against a thread formed on an inner wall surface the mold, thereby forming a thread groove on that surface of the resin material pressed against the thread.

Claims

1. A method of manufacturing a sealing apparatus comprising the steps of:

preparing a mold for manufacturing the sealing apparatus by effecting vulcanization forming, said mold having threads formed on an inner wall surface thereof;

placing within said mold a rubber-like elastic material and a resin material for providing sealing lips of the sealing apparatus; and

clamping said mold in such a manner that said rubber-like material is pressurized and vulcanization formed thereby forming a portion of said rubber-like elastic material as a radially-inner sealing lip, so that the radially-inner sealing lip of the rubber-like elastic material overlaps and extends beyond the sealing lip of the resin material while a radially-inner surface of said resin material which is to serve as a surface of the sealing lip is pressed against said threads by forming pressure generated by fluidized rubber-like elastic material during the vulcanization forming, thereby forming a thread groove on that surface of said resin material; and

cutting off a superfluous portion of molded rubber-like elastic material which extends from the radially-inner sealing lip formed of said rubber-like elastic material.

2. A method of manufacturing a sealing apparatus according to claim 1, wherein, before the vulcanization forming, said resin material has a portion already formed as the sealing lip.

3. A method of manufacturing a sealing apparatus according to claim 1, wherein said resin material is washer-shaped, a radially inner end portion of said resin material being bent into a cylindrical shape by forming pressure generated during the vulcanization forming so as to be formed into the sealing lip.

4. A method of manufacturing a sealing apparatus according to any of claims 1, 2 or 3, wherein a back-up ring is placed within said mold together with said resin material and said rubber-like elastic material so that said back-up ring will be formed integrally with said materials.

5. A method of manufacturing a sealing apparatus according to claim 4, wherein said back-up ring has a bore formed therein, said bore allowing the entrance therein of a part of said resin material under forming pressure generated during the vulcanization forming, thereby allowing the integration of said back-up ring and said resin material.