Inserts for injection mold machine

• US 4,959,002 A
• Filed: 05/08/1989
• Issued: 09/25/1990
• Est. Priority Date: 08/25/1987
• Status: Expired due to Term

• Current Assignee: Ronald E. Pleasant
• Original Assignee: Ronald E. Pleasant
• Inventors: Pleasant, Ronald E.
• Primary Examiner(s): Woo, Jay H.
• Assistant Examiner(s): Heitbrink, Timothy W.
• Application Number:
  US07/348,714
• Time in Patent Office: 505 Days
• Field of Search: 425/552, 425/547, 425/182, 425/185, 425/190, 425/192 R, 425/554, 425/556, 425/557, 425/444
• US Class Current: 425/192.00R
• CPC Class Codes: B29C 45/2673 with exchangeable mould parts, e.g. cassette moulds B29C45/1756 takes precedence
• CPC Class Codes: B29C 45/2675 Mounting of exchangeable mould inserts

Abstract

A cavity insert for the ejection side and a core insert for the injection side of a mold are each shaped as a generally cylindrical, stepped body provided with circumferentially extending locking grooves and a liquid cooling or heating channel. Insert retainers and lifters having rotatable elements with locking tongues engaging the locking grooves clamp the inserts in the main mold frame. The main mold frame is provided with liquid conduits opening to opposite ends of the liquid channels so that the need for machining liquid conduits and channels for different inserts is avoided. Ejector tooling may be connected to the core insert for insertion and removal with it. The rotatable elements also have shoulders engageable with the inserts and may be axially moved to lift the inserts partly out of the mold frame to enable rapid changeover from one insert to another. Sliding wedges are used to releasably secure the ejector tooling to the master mold ejector plates. Improved ejector return pin assemblies may be used to enable the use of oversized inserts. A guided ejector system may be used as part of the main mold frame.

Claims

1. A quick-changeover mold insert for use in an injection molding machine, said machine having a pair of relatively movable mold sides forming a mold cavity therebetween, said mold sides being separable to expose confronting parts of said mold sides, one of said mold sides comprising a mold plate having a surface confronting the other mold side which surface is exposed when said mold sides are separated, said mold plate having an insert-receiving hole adapted to receive a mold insert, and said machine having insert retainer and lifter means on said mold plate for clamping said mold insert to said mold plate and for lifting said mold insert partly out of said insert-receiving hole, said mold insert comprising:

a generally cylindrical, one-piece body stepped along its length, said body comprising longitudinally-adjacent sections of different diameters including a first diameter locking groove section having an outer peripheral surface, an end face, and locking means forming locking groove segments at portions of said outer peripheral surface, said locking groove segments being engageable by said insert retainer and lifter means for clamping said mold insert to said mold plate with said end face confronting the other mold side and also for partly removing said mold insert from said mold plate, and said sections further comprising a second diameter liquid channel section, said liquid channel section having a liquid channel groove extending substantially completely therearound, said liquid channel section being smaller in diameter than said locking groove section, and a pair of axially spaced O-ring seal-receiving groove means for partly receiving O-rings located on opposite sides of said liquid channel groove.

2. The mold insert of claim 1 wherein said locking groove section has locating means for orienting said mold insert relative to said mold plate.

3. The mold insert of claim 2 wherein said locating means comprises at least one flat on said outer peripheral surface of said locking groove section.

4. The mold insert of claim 1 wherein said liquid channel groove has a first end and a second end spaced from said first end and wherein said liquid channel groove is interrupted by a barrier adjacent each of said first groove end and said second groove end.

5. The mold insert of claim 1 wherein said sections further include a third diameter section, said third diameter section being smaller in diameter than said liquid channel section.

6. The mold insert of claim 5 wherein one of said seal-receiving groove means is located on said liquid channel section immediately adjacent said locking groove section and the other of said seal-receiving groove means is located on said third diameter section immediately adjacent said liquid channel section.

7. A quick-changeover mold insert for use in an injection molding machine, said machine having a pair of relatively movable mold sides forming a mold cavity therebetween, said mold sides being separable to expose confronting parts of said mold sides, one of said mold sides comprising a mold plate having a surface confronting the other mold side which surface is exposed when said mold sides are separated, said mold plate having an insert-receiving hole adapted to receive a mold insert, and said machine having insert retainer and lifter means on said mold plate for clamping a mold insert to said mold plate and for lifting said mold insert partly out of said insert-receiving hole, said mold insert comprising:

a generally cylindrical, one-piece body stepped along its length, said body comprising longitudinally-adjacent sections of different diameters including a first diameter locking groove section having an outer peripheral surface, an end face, and locking means forming locking groove segments at portions of said outer peripheral surface, said locking groove segments being engageable by said insert retainer and lifter means for clamping said mold insert to said mold plate with said end face confronting the other mold side and also for partly removing said mold insert from said mold plate, and said sections further comprising a second diameter liquid channel section, said liquid channel section having a liquid channel groove extending substantially completely therearound, said liquid channel section being smaller in diameter than said locking groove section, and a pair of axially spaced O-ring seal-receiving groove means for partly receiving O-rings located on opposite sides of said liquid channel groove;

an ejector tooling assembly; and

means for retaining said ejector tooling assembly with said body.

8. The mold insert of claim 7 wherein said sections further include a third diameter section, said third diameter section being smaller in diameter than said liquid channel section.

9. The mold insert of claim 8 wherein one of said seal-receiving groove means is located on said liquid channel section immediately adjacent said locking groove section and the other of said seal-receiving groove means is located on said third diameter section immediately adjacent said liquid channel section.

10. A quick-changeover mold insert for use in an injection molding machine, said machine having a pair of relatively movable mold sides forming a mold cavity therebetween, said mold sides being separable to expose confronting parts of said mold sides, one of said mold sides comprising a mold plate having a surface confronting the other mold side which surface is exposed when said mold sides are separated, said mold plate having an insert-receiving hole adapted to receive a mold insert, and said machine having insert retainer and lifter means on said mold plate for clamping said mold insert to said mold plate and for lifting said mold insert partly out of said insert-receiving hole, said mold insert comprising:

a one-piece body comprising a locking groove section having a generally cylindrical outer peripheral surface and an end face and said locking groove mechanism having locking means forming locking groove segments at portions of said outer peripheral surface, said locking groove segments being engageable by said insert retainer and lifter means for clamping said mold insert to said mold plate with said end face confronting the other mold side and also for partly removing said mold insert from said mold plate.

11. The mold insert of claim 10 wherein said locking groove section has locating means for orienting said mold insert relative to said mold plate.

12. The mold insert of claim 11 wherein said locking groove section has a generally cylindrical outer surface and said locating means comprises at least one flat on said outer surface of said locking groove section.

13. A quick-changeover mold insert use in an injection molding machine having a pair of relatively movable mold sides forming a mold cavity therebetween, said mold sides being separable to expose confronting parts of said mold sides, one of said mold sides comprising a mold plate having a surface confronting the other mold side which surface is exposed when said mold sides are separated, said mold plate having an insert-receiving hole adapted to receive a mold insert, and said machine having insert retainer and lifter means on said mold plate for clamping a mold insert to said mold plate and for lifting said mold insert partly out of said insert-receiving hole, said mold insert comprising:

a one-piece body comprising a locking groove section having a generally cylindrical outer peripheral surface and an end face, said locking groove section having locking means forming locking groove segments at portions of said outer peripheral surface of said locking groove section, said locking groove segments being engageable by said insert retainer and lifter means for clamping said mold insert to said mold plate with said end face confronting the other mold side and also for partly removing said mold insert from said mold plate;

an ejector tooling assembly; and

means for retaining said ejector tooling assembly with said body.

14. The mold insert of claim 13 wherein said locking groove section has locating means for orienting said mold insert relative to said mold plate.

15. The mold insert of claim 14 wherein said locating means comprises at least one flat on said outer peripheral surface of said locking groove section.