Claims
- 1. A method of degating molded parts comprising the steps of:
- (a) providing an injection molding material capable of being molded in an injection molding apparatus;
- (b) molding a solid configuration from said molding material comprising parts secured to a runner system by gates of said molding material, said gates having a cross-section substantially smaller than any cross-section of said molded configuration which is contacting and integral therewith;
- (c) cooling the surfaces of said configuration to a temperature and for a time until only said gates become brittle; and
- (d) applying an impact to said configuration while said gates are brittle to cause said configuration to sever at said gates and separate said runner system from said parts.
- 2. The method of claim 1 wherein said step of cooling comprises the step of spraying liquid nitrogen over the surface of said configuration.
- 3. The method of claim 1 wherein said step of applying an impact comprises tumbling said configuration while said gates are brittle.
- 4. The method of claim 2 wherein said step of applying an impact comprises tumbling said configuration while said gates are brittle.
- 5. The method of claim 1 wherein said configuration consists essentially of water soluble polyvinyl alcohol resin.
- 6. The method of claim 2 wherein said configuration consists essentially of water soluble polyvinyl alcohol resin.
- 7. The method of claim 3 wherein said configuration consists essentially of water soluble polyvinyl alcohol resin.
- 8. The method of claim 4 wherein said configuration consists essentially of water soluble polyvinyl alcohol resin.
Parent Case Info
This application is a Division of application Ser. No. 07/780,684, filed Oct. 18, 1991, now abandoned.
US Referenced Citations (14)
Foreign Referenced Citations (3)
Number |
Date |
Country |
2554905 |
Oct 1977 |
DEX |
60-67120 |
Apr 1985 |
JPX |
689835 |
Oct 1979 |
SUX |
Non-Patent Literature Citations (1)
Entry |
Plastics, Dubois and John ed., Reinhold Publishing Corp., N.Y.: 1967, p. 333. |
Divisions (1)
|
Number |
Date |
Country |
Parent |
780684 |
Oct 1991 |
|