Claims
- 1. A molding apparatus comprising:
- a cavity member having a first circular end surface with a first circumferential skirt having a first inside diameter;
- a core member spaced from said cavity member and comprising a second circular end surface with a second circumferential skirt having a second outside diameter less than the first inside diameter of the first circumferential skirt;
- said cavity member and said core member being aligned along a common axis transverse to the surface of said first and second ends and passing through the center of said first and second circular ends;
- a fluid passage terminating at one of said ends for carrying injection molding compound to a molding volume defined by space between said cavity member and said core member; and
- a retaining ring axially aligned with said core and cavity members, surrounding said core member and having a third inner diameter less than said first inner diameter and greater than said second outer diameter,
- wherein the injection molding compound has a predetermined shrinkage and the retaining ring has an inner diameter that is less than the inner diameter of the cavity skirt by an amount not in excess of half the shrinkage of the injected molding compound.
- 2. The apparatus of claim 1 wherein the first circumferential skirt has a cylindrical surface with a design displaced from the surface of the skirt.
- 3. The apparatus of claim 2 wherein the design includes an embossing.
- 4. The apparatus of claim 2 wherein the design includes an engraving.
- 5. The apparatus of claim 2 wherein the design is selected from a group consisting of an embossing and an engraving.
- 6. A molding apparatus comprising:
- a cavity member having a first circular end surface with a first circumferential skirt having a first inside diameter;
- a core member spaced from said cavity member and comprising a second circular end surface with a second circumferential skirt having a second outside diameter less than the first inside diameter of the first circumferential skirt;
- said cavity member and said core member being aligned along a common axis transverse to the surface of said first and second ends and passing through the center of said first and second circular ends;
- a fluid passage terminating at one of said ends for carrying injection molding compound to a molding volume defined by space between said cavity member and said core member; and
- a retaining ring axially aligned with said core and cavity members, surrounding said core member and having a third inner diameter less than said first inner diameter and greater than said second outer diameter,
- wherein said first circumferential skirt has a substantially seamless surface and is one piece, said second circumferential skirt has a substantially seamless surface and is one piece, and said retaining ring is one piece.
- 7. A molding apparatus comprising:
- a cavity member having a first circular end surface with a first circumferential skirt having a first inside diameter;
- a core member spaced from said cavity member and comprising a second circular end surface with a second circumferential skirt having a second outside diameter less than the first inside diameter of the first circumferential skirt;
- said cavity member and said core member being aligned along a common axis transverse to the surface of said first and second ends and passing through the center of said first and second circular ends;
- a fluid passage terminating at one of said ends for carrying injection molding compound to a molding volume defined by space between said cavity member and said core member; and
- a retaining ring axially aligned with said core and cavity members, surrounding said core member and having a third inner diameter less than said first inner diameter and greater than said second outer diameter,
- wherein the first circumferential skirt has a cylindrical surface with a design displaced from the surface of the skirt, the injection molding compound has a predetermined shrinkage and the size of the design is less than half of said shrinkage.
- 8. The apparatus of claim 7 wherein said ejector comprises a circular face with an engraved decorative region and an endless witness camouflaged by said decorative region.
- 9. A molding apparatus comprising:
- a cavity member having a first circular end surface with a first circumferential skirt having a first inside diameter:
- a core member spaced from said cavity member and comprising a second circular end surface with a second circumferential skirt having a second outside diameter less than the first inside diameter of the first circumferential skirt;
- said cavity member and said core member being aligned alone a common axis transverse to the surface of said first and second ends and passing through the center of said first and second circular ends;
- a fluid passage terminating at one of said ends for carrying injection molding compound to a molding volume defined by space between said cavity member and said core member; and
- a retaining ring axially aligned with said core and cavity members, surrounding said core member and having a third inner diameter less than said first inner diameter and greater than said second outer diameter,
- wherein said core further comprises a fluid passage for apply a source of pressurized air on end surface of a molded part.
- 10. A molding apparatus comprising:
- a cavity member having a first circular end surface with a first circumferential skirt having a first inside diameter;
- a core member spaced from said cavity member and comprising a second circular end surface with a second circumferential skirt having a second outside diameter less than the first inside diameter of the first circumferential skirt;
- said cavity member and said core member being aligned along a common axis transverse to the surface of said first and second ends and passing through the center of said first and second circular ends;
- a fluid passage terminating at one of said ends for carrying injection molding compound to a molding volume defined by space between said cavity member and said core member; and
- a retaining ring axially aligned with said core and cavity members, surrounding said core member and having a third inner diameter less than said first inner diameter and greater than said second outer diameter,
- wherein said core further comprises a piston for bearing against a molded part to urge said core away from said molded end surface.
- 11. A molding apparatus comprising:
- a cavity member having a first circular end surface with a first circumferential skirt having a first inside diameter;
- a core member spaced from said cavity member and comprising a second circular end surface with a second circumferential skirt having a second outside diameter less than the first inside diameter of the first circumferential skirt;
- said cavity member and said core member being aligned along a common axis transverse to the surface of said first and second ends and passing through the center of said first and second circular ends;
- a fluid passage terminating at one of said ends for carrying injection molding compound to a molding volume defined by space between said cavity member and said core member; and
- a retaining ring axially aligned with said core and cavity members, surrounding said core member and having a third inner diameter less than said first inner diameter and greater than said second outer diameter,
- wherein said core comprises a concentric ejector reciprocally moveable within said cavity to urge a molded part out of said cavity in a direction toward said core.
Parent Case Info
This is a division of application Ser. No. 08/632,712 filed on Apr. 15, 1996, now U.S. Pat. No. 5,695,706 which is a continuation of Ser. No. 08/252,935 filed on Jun. 2, 1994 now abandoned.
US Referenced Citations (15)
Divisions (1)
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Number |
Date |
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Parent |
632712 |
Apr 1996 |
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Continuations (1)
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Number |
Date |
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252935 |
Jun 1994 |
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