PELLETIZING APPARATUS

• US 3,792,950 A
• Filed: 09/08/1972
• Issued: 02/19/1974
• Est. Priority Date: 09/08/1972
• Status: Expired due to Term

• Current Assignee: David W. Cuff
• Original Assignee: David W. Cuff
• Inventors: Cuff, David W.
• Primary Examiner(s): Annear, R. Spencer
• Application Number:
  US05/287,276
• Time in Patent Office: 529 Days
• Field of Search: 425/313,314,378,379,464 264/141
• US Class Current: 425/313
• CPC Class Codes: B29B 7/582 for discharging, e.g. doors
• CPC Class Codes: B29B 7/826 Apparatus therefor
• CPC Class Codes: B29B 9/065 under-water, e.g. underwater pelletizers
• CPC Class Codes: B29C 2793/009 after shaping
• CPC Class Codes: B29C 48/04 Particle-shaped making granules B29B9/00
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/345 Extrusion nozzles comprising two or more adjacently arranged ports, for simultaneously extruding multiple strands, e.g. for pelletising

Abstract

Apparatus for pelletizing synthetic plastic resins, comprising an extruding die assembly having extrusion orifice sleeves pervious to liquid, a water jacket surrounding each sleeve in such manner that water will pass through the walls thereof to chill plastic being extruded therethrough while at the same time lubricating passage of the plastic therethrough. Severing means are provided at the die face for cutting the plastic into pellets as it is extruded. Optionally means are provided for collecting the pellets such as a casing that surrounds the die and the cutting means.

Claims

1. A die-type pelletizing apparatus for synthetic plastic comprising:

a base;

a die adaptor mounted on the base and having inlet and outlet portions;

an extrusion die mounted on the outlet portion of said adaptor and having inner and outer die faces;

conducting means in the adaptor for conducting hot plastic from the inlet portion thereof to the extrusion die;

a plurality of extrusion bores in said extrusion die extending between the latter'"'"''"'"'s inner and outer faces;

bushings having walls pervious to a liquid and mounted in said bores, each bushing having an extrusion passage therethrough;

first means for supplying a cooling liquid to at least a portion of the outer surface of said bushings within said extrusion bores thereby to cause the liquid to pass through said bushings into the extrusion passages thereof to engage the surface of plastic being extruded through the bushings; and

cutting means movably mounted adjacent said outer die face for severing extruded plastic material as it emerges from said extrusion passages, thereby to pelletize said material.

2. The apparatus of claim 1 in which said first means is adapted to receive said liquid at a pressure greater than the plastic being extruded through the extrusion passageways.

3. The apparatus of claim 1 including third means for heating an inner portion of the length of each bushing adjacent the outlet portion of said adaptor.

4. The apparatus of claim 1 including a casing, closure means for the casing at one end thereof, and said adaptor comprising a closure means for the other end of the casing, the pellets when cut from the plastic falling into said casing.

5. The apparatus of claim 1, in which said bushings are detachably fastened into said extrusion bores.

6. The apparatus of claim 3, in which said third means comprises a pair of fluid receiving channels one on each side of the inner ends of said extrusion bores, the channels being interconnected between the bores, and said inner portions of the lengths of the bushings being in thermal conductivity with the die body portions forming the inner ends of the extrusion bores.

7. The apparatus of claim 1 in which said first means comprises a channel in said extrusion die surrounding said portion of each of said bushings, the channel having inlet means whereby said fluid may be introduced into the channel in order to surround each bushing with said fluid.

8. The apparatus of claim 1 in which said cutting means comprises at least one knife which traverses the outer face of the extrusion die as the knife moves, and including drive means to move the knife.

9. The apparatus of claim 8, in which said knife does not touch the external face of the extrusion die but is closely adjacent thereto.

10. The apparatus of claim 6, in which said channels include inlet and outlet means.

11. An extrusion die assembly for pelletizing plastic, including:

a die member having a compression face and an expansion face;

a plurality of extrusion bores in said die member extending between said faces;

bushings having walls pervious to a liquid and mounted in said extrusion bores, each bushing having an extrusion passageway therethrough;

first means for supplying a cooling liquid to the outer surface of said bushings within said extrusion bores thereby to cause the liquid to pass through said bushings into the extrusion passageways thereof to engage the surface of plastic being extruded through said bushings; and

cutting means movably mountEd adjacent the expansion face of the die member for severing extruded plastic material as it emerges from said extrusion passageways, thereby to pelletize said material.

12. The extrusion die of claim 11 in which said first means is adapted to receive said liquid at a pressure greater than the plastic being extruded through the extrusion passageways.

13. The die assembly of claim 11, including third means for heating an inner portion of the length of each bushing adjacent said compression face.

14. The die assembly of claim 11, in which said bushings are detachably fastened into said extrusion bores.

15. The die assembly of claim 11, in which said first means comprises a channel in the extrusion die enveloping said bushings, and having an inlet thereto for receiving said fluid.

16. The die assembly of claim 13, in which said third means comprises a pair of fluid receiving channels one on each side of said extrusion bores and in proximity to said compression face, the channels being interconnected between the bores, and said inner portions of the lengths of said bushings being in thermal conductivity with the die body portions forming the inner end portions of said extrusion bores.

17. The die assembly of claim 13, including inlet and outlet means for the channels, adapted to introduce and remove a hot heating fluid from said channels.

18. The die assembly of claim 15, including fluid receiving inlet means for said channel.

19. The die assembly of claim 11 in which the expansion face of the extrusion die is cylindrical and said bores extend radially with respect to the cylindrical face.

20. The die assembly of claim 11 in which the expansion face of the extrusion die is planar, and said bores are perpendicular to the expansion face.

21. The die assembly of claim 19 in which said bushings are detachably fastened into the extrusion bores.

22. The die assembly of claim 20 in which the bushings are detachably fastened into the extrusion bores.