Process of molding seal rings
First Claim
1. A process of molding a seal ring comprising, the steps of;
- positioning a reinforcement in a first mold part, positioning a disc of low friction material in the first mold part, closing the mold with a second mold part to clamp a width C of between about 30% and 70% of the width of the disc between opposed clamping surfaces of the first and second mold parts, drawing a vacuum in the interior of the mold, injecting a plastic material into the mold to form a seal lip connecting the disc of low friction material to the reinforcement, opening the mold and removing the molded ring, and cutting off from the molded ring, an excess portion of the molded lip, and at least that portion of the disc which was clamped between the opposed clamping surfaces of the mold wherein said injecting step comprises injecting the plastic material through circumferentially spaced injection channels on the second mold,said injection channels being spaced radially from the portion of said disc which is clamped between the clamping surfaces of the mold parts.
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Accused Products
Abstract
The seal ring is molded by positioning a frame or reinforcement in one part of an opened mold, and positioning a low friction material disc on a clamping surface of the same part of the mold. The mold is closed with a second part so that between 30% and 70% of the disc is clamped and squeezed between opposed surfaces of the mold parts, and the reinforcement or frame is held in position in the closed mold. A vacuum is drawn in the mold, and an elastomer is injected to form a body or lip connecting the reinforcement to the disc. The molded ring is removed from the mold and excess lip material and at least the portion of the disc which was clamped are cut off to form the finished seal ring. The low friction material disc can contain PTFE.
27 Citations
5 Claims
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1. A process of molding a seal ring comprising, the steps of;
- positioning a reinforcement in a first mold part, positioning a disc of low friction material in the first mold part, closing the mold with a second mold part to clamp a width C of between about 30% and 70% of the width of the disc between opposed clamping surfaces of the first and second mold parts, drawing a vacuum in the interior of the mold, injecting a plastic material into the mold to form a seal lip connecting the disc of low friction material to the reinforcement, opening the mold and removing the molded ring, and cutting off from the molded ring, an excess portion of the molded lip, and at least that portion of the disc which was clamped between the opposed clamping surfaces of the mold wherein said injecting step comprises injecting the plastic material through circumferentially spaced injection channels on the second mold,
said injection channels being spaced radially from the portion of said disc which is clamped between the clamping surfaces of the mold parts. - View Dependent Claims (2, 3, 4, 5)
- positioning a reinforcement in a first mold part, positioning a disc of low friction material in the first mold part, closing the mold with a second mold part to clamp a width C of between about 30% and 70% of the width of the disc between opposed clamping surfaces of the first and second mold parts, drawing a vacuum in the interior of the mold, injecting a plastic material into the mold to form a seal lip connecting the disc of low friction material to the reinforcement, opening the mold and removing the molded ring, and cutting off from the molded ring, an excess portion of the molded lip, and at least that portion of the disc which was clamped between the opposed clamping surfaces of the mold wherein said injecting step comprises injecting the plastic material through circumferentially spaced injection channels on the second mold,
Specification