초록 ▼

A method for molding an annular lip type shaft seal 10 of the type having an annular elastomeric shaft seal element 12 and a resin liner 14 (preferably polytetrafluoroethylene) integrally molded therewith and bonded thereto, including providing a step or shoulder 36 on the mold core 26 to prevent th

A method for molding an annular lip type shaft seal 10 of the type having an annular elastomeric shaft seal element 12 and a resin liner 14 (preferably polytetrafluoroethylene) integrally molded therewith and bonded thereto, including providing a step or shoulder 36 on the mold core 26 to prevent the resin liner 14 from flowing axially beyond a predetermined location during molding. The method includes providing a certain range of acute angles “a42 and the liner forming surface 38 of the mold core surface 34, and a certain range of shoulder heights “d”relative to the liner thickness “t”, for various values of the initial viscosity of the elastomeric preform 18. The percentage of rejects due to undesired flow of the resin liner 14 during molding has been greatly reduced.

대표청구항 ▼

A method for molding an annular lip type shaft seal of the type having an annular elastomeric shaft seal element and a resin liner integrally molded therewith and bonded thereto, said method comprising the steps of: (a) placing a resin liner element having a thickness t, an elastomeric preform and a

A method for molding an annular lip type shaft seal of the type having an annular elastomeric shaft seal element and a resin liner integrally molded therewith and bonded thereto, said method comprising the steps of: (a) placing a resin liner element having a thickness t, an elastomeric preform and a seal shell in a mold having an annular lip forming surface; (b) providing, on said lip forming surface, an annular shoulder having a shoulder surface facing said liner element and adapted to contact an outer edge of said liner element during molding for preventing said resin liner element from flowing axially past said shoulder, said shoulder being located axially between a liner forming surface and an elastomeric seal element forming surface, said shoulder making an angle aaa85°and d≥t; and (d) operating said mold for forming said liner element into said liner and causing said elastomer to flow to form said shaft seal element and applying heat and pressure thereto for forming said seal.