METHOD FOR MOLDING DUAL-LIP SHAFT SEALS WITH A GARTER SPRING MOLDED INTO THE AUXILIARY LIP

• US 3,851,037 A
• Filed: 05/03/1971
• Issued: 11/26/1974
• Est. Priority Date: 05/03/1971
• Status: Expired due to Term

• Current Assignee: Day F, Repella J
• Original Assignee: Day F, Repella J
• Inventors: DAY F, REPELLA J
• Application Number:
  US05/139,618
• Time in Patent Office: 1,303 Days
• US Class Current: 264/229
• CPC Class Codes: B29D 99/0053 Producing sealings B29D99/0085 takes precedence
• CPC Class Codes: B29K 2021/00 Use of unspecified rubbers as moulding material
• CPC Class Codes: B29L 2031/26 Sealing devices, e.g. packaging for pistons or pipe joints
• CPC Class Codes: F16J 15/328 Manufacturing methods specially adapted for elastic sealings moulding B29C
• CPC Class Codes: Y10S 277/924 Deformation, material removal, or molding for manufacture of seal

Abstract

1.A method of molding an integral molded dual-lip seal having a spring molded into the auxiliary lip, said method employing a mold having a plurality of members and providing a pair of facing converging walls that act to define said auxiliary lip, one of said facing walls being of lesser diameter than the other at any radial plane through them both, one of said members being a mold core providing at least said lesser diameter wall, said mold core also including a mold wall of larger diameter than the widest diameter portion of said lesser diameter wall and joined to said lesser diameter wall comprising: stretching a garter spring that is of smaller diameter than said larger diameter wall and to its juncture with said lesser diameter wall, then snapping said garter spring initially into its final position against said said facing converging mold walls that are to define the auxiliary lip, spacing said spring from the sealing edge of that lip by the size of the spring coils relative to the convergence of the walls, preventing said spring from assuming a free or rest position and maintaining it in a stretched position positively by engagement with said walls, preventing retraction of the spring from its correct position by the same walls extending radially outwardly so that before filling said mold with elastomer the spring is snapped into its said final position, where it is stretched less than it would be in any direction in which it can move, filling said mold with a elastomer, and curing said elastomer.

Claims

1. A method of molding an integral molded dual-lip seal having a spring molded into the auxiliary lip, said method employing a mold having a plurality of members and providing a pair of facing converging walls that act to define said auxiliary lip, one of said facing walls being of lesser diameter than the other at any radial plane through them both, one of said members being a mold core providing at least said lesser diameter wall, said mold core also including a mold wall of larger diameter than the widest diameter portion of said lesser diameter wall and joined to said lesser diameter wall comprising:

stretching a garter spring that is of smaller diameter than said larger diameter wall and to its juncture with said lesser diameter wall, then snapping said garter spring initially into its final position against said said facing converging mold walls that are to define the auxiliary lip, spacing said spring from the sealing edge of that lip by the size of the spring coils relative to the convergence of the walls, preventing said spring from assuming a free or rest position and maintaining it in a stretched position positively by engagement with said walls, preventing retraction of the spring from its correct position by the same walls extending radially outwardly so that before filling said mold with elastomer the spring is snapped into its said final position, where it is stretched less than it would be in any direction in which it can move, filling said mold with a elastomer, and curing said elastomer.