Screw-type extruder

Patent metadata

Field	Value
Publication number	US-11027475-B2
Application number	US-201716091815-A
Country	US
Kind code	B2
Filing date	Apr 12, 2017
Priority date	Apr 20, 2016
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

A screw extruder which extrudes a kneaded material includes a screw having a helical flight provided on an outer peripheral surface of a shaft portion thereof, and a chamber housing the screw. In the screw extruder, a flight thickening portion is provided at a part which is a tip portion of the flight and is on the reverse side of a rotation direction of the flight.

First claim

The invention claimed is:

1. A screw extruder which extrudes a kneaded material,
comprising:
a screw having a helical flight provided on an outer peripheral surface of a shaft portion thereof; and
a chamber housing the screw, wherein
a flight thickening portion is provided at a part which is a tip portion of the flight and is on the reverse side of a rotation direction of the flight;

the flight thickening portion extends from the tip portion, along the flight toward the shaft portion, to a reverse surface of the flight thickening portion;
the reverse surface of the flight thickening portion is disposed such that a gap is formed between the reverse surface of the flight thickening portion and the shaft portion; and
a thickness of the flight is uniform from the tip portion to the shaft portion.

2. The screw extruder according to claim 1 , wherein:
an outer peripheral surface of the tip portion where the flight thickening portion is provided is formed in an arc shape in the rotation direction of the flight; and
at least a part of an inner wall surface of the chamber has an arc shape so that a gap having a uniform dimension is formed between the at least a part of an inner wall surface of the chamber and the outer peripheral surface of the tip portion including the flight thickening portion.

3. The screw extruder according to claim 1 ,
wherein the flight thickening portion decreases in thickness toward a center of the shaft portion.

4. The screw extruder according to claim 1 ,
wherein the chamber includes:
a chamber upstream portion including, at a top portion thereof, a kneaded material supply port; and
a chamber downstream portion having a periphery surrounded by a wall surface, and
wherein the part including the flight thickening portion in the flight is disposed in the chamber downstream portion.

5. The screw extruder according to claim 3 ,
wherein the chamber includes:
a chamber upstream portion including, at a top portion thereof, a kneaded material supply port; and
a chamber downstream portion having a periphery surrounded by a wall surface, and
wherein the part including the flight thickening portion in the flight is disposed in the chamber downstream portion.

6. The screw extruder according to claim 4 ,
wherein the part of the flight disposed in the chamber downstream portion comprises a plurality of flight portions.

7. The screw extruder according to claim 5 ,
wherein the part of the flight disposed in the chamber downstream portion comprises a plurality of flight portions.

8. The screw extruder according to claim 2 ,
wherein the flight thickening portion decreases in thickness toward a center of the shaft portion.

9. The screw extruder according to claim 2 ,
wherein the chamber includes:
a chamber upstream portion including, at a top portion thereof, a kneaded material supply port; and
a chamber downstream portion having a periphery surrounded by a wall surface, and
wherein the part including the flight thickening portion in the flight is disposed in the chamber downstream portion.

10. The screw extruder according to claim 8 ,
wherein the chamber includes:
a chamber upstream portion including, at a top portion thereof, a kneaded material supply port; and
a chamber downstream portion having a periphery surrounded by a wall surface, and
wherein the part including the flight thickening portion in the flight is disposed in the chamber downstream portion.

11. The screw extruder according to claim 9 ,
wherein the part of the flight disposed in the chamber downstream portion comprises a plurality of flight portions.

12. The screw extruder according to claim 10 ,
wherein the part of the flight disposed in the chamber downstream portion comprises a plurality of flight portions.

Assignees

• Kobe Steel Ltd

Inventors

• Fukutani Kazuhisa
• Higashi Kosuke

Classifications

• B29B7/484

  with two shafts provided with screws, e.g. one screw being shorter than the other (B29B7/482 takes precedence) · CPC title

• B29C48/525

  Conical screws · CPC title

• B29C48/395 Primary

  using screws surrounded by a cooperating barrel, e.g. single screw extruders · CPC title

• B29C48/505

  Screws · CPC title

• B29B7/48

  with intermeshing devices, e.g. screws · CPC title