Feeder Module in Planetary Roller Extruder Design

• US 20190329450A1
• Filed: 07/03/2018
• Published: 10/31/2019
• Est. Priority Date: 07/13/2017
• Status: Active Grant

• Current Assignee: Entex Rust & Mitschke GmbH
• Original Assignee: Entex Rust & Mitschke GmbH
• Inventors: Rust, Harald
• Granted Patent: US 11,485,298 B2
• Time in Patent Office: Days
• CPC Class Codes: B29B 7/426 with consecutive casings or screws, e.g. for charging, discharging, mixing
• CPC Class Codes: B29B 7/485 with three or more shafts provided with screws
• CPC Class Codes: B29B 7/487 with consecutive casings or screws, e.g. for feeding, discharging, mixing
• CPC Class Codes: B29B 7/489 Screws B29B7/482 takes precedence
• CPC Class Codes: B29B 7/7495 for mixing rubber
• CPC Class Codes: B29B 7/823 Temperature control
• CPC Class Codes: B29B 7/845 Venting, degassing or removing evaporated components in devices with rotary stirrers
• CPC Class Codes: B29C 48/288 in solid form, e.g. powder or granules
• CPC Class Codes: B29C 48/435 Sub-screws
• CPC Class Codes: B29C 48/44 Planetary screws
• CPC Class Codes: B29C 48/60 Thread tops
• CPC Class Codes: B29C 48/655 having three or more threads
• CPC Class Codes: B60N 3/048 characterised by their structure
• CPC Class Codes: B60R 13/083 for fire walls or floors

Abstract

A planetary roller extruder section forms a feed part of an extruder. The planetary roller extruder has an internally toothed housing and an externally toothed central spindle disposed centrally within and at a distance from the housing. Planetary spindles are arranged to rotate in a void between the central spindle and the housing. Each planetary spindle has an external toothing meshing with both the housing and the central spindle. At least one planetary spindle has two axially spaced areas with less than a full set of teeth. Those axially spaced areas include a first area having a first number of teeth and a second area having a second number of teeth. The second number of teeth is less than a full set of teeth and more than the first number of teeth.

Claims

1-9. -9. (canceled)

10. A planetary roller extruder section forming a feed part of an extruder, comprising:

an internally toothed housing;

an externally toothed central spindle disposed centrally within and at a distance from the housing; and

planetary spindles arranged to rotate in a void between the central spindle and the housing, each planetary spindle having an external toothing meshing with both the housing and the central spindle,

wherein at least one planetary spindle comprises at least two axially spaced areas including

a first area having a first number of teeth, the first number of teeth being less than a full set of teeth, and

a second area having a second number of teeth, the second number of teeth being less than a full set of teeth and more than the first number of teeth.

11. The planetary roller extruder section as in claim 10,

wherein the first area and the second area have the same length.

12. The planetary roller extruder section as in claim 10,

wherein the first area and the second area have different lengths.

13. The planetary roller extruder section as in claim 10,

comprising a transition area between the first area and the second area in which teeth that are present in the second area and not present in the first area gradually taper off from their total depth, a length of the transition area being at least 0.5 times the depth of the teeth.

14. The planetary roller extruder section as in claim 13, wherein the length of the transition area is at least equal to the depth of the teeth.

15. The planetary roller extruder section as in claim 10, wherein the at least one planetary spindle has a drive-side guiding area with full toothing disposed at an end of the planetary roller extruder section proximal to a drive.

16. The planetary roller extruder section as in claim 15, wherein the drive-side guiding area has an axial length which is at least equal to an external diameter of the planetary spindles.

17. The planetary roller extruder section as in claim 15, wherein the at least one planetary spindle has a further guiding area disposed at an opposite end of the drive-side guiding area, a length of the further guiding area being between 0.2 times and 0.7 times an axial length of the drive-side guiding area.

18. The planetary roller extruder section as in claim 15, wherein the at least one planetary spindle has a further guiding area disposed at an opposite end of the drive-side guiding area, a length of the further guiding area being between 0.3 times and 0.4 times an axial length of the drive-side guiding area.

19. The planetary roller extruder section as in claim 10, wherein the internally toothed housing comprises an internally toothed liner disposed within the housing.