Gear system for drive of a multi-shaft extruder

• US 7,594,453 B2
• Filed: 02/27/2004
• Issued: 09/29/2009
• Est. Priority Date: 04/03/2003
• Status: Active Grant

• Current Assignee: Josef A. Blach
• Original Assignee: Josef A. Blach
• Inventors: Blach, Josef A.
• Primary Examiner(s): HO, HA DINH
• Application Number:
  US10/551,912
• Publication Number:
  US 20070163371A1
• Time in Patent Office: 2,041 Days
• Field of Search: 746/65.F, 746/65.G, 746/65.GA, 746/65.GB, 746/65.GC, 746/65.GD, 746/65.DE
• US Class Current: 74/665.00N
• CPC Class Codes: B29B 7/485 with three or more shafts provided with screws
• CPC Class Codes: B29C 48/03 characterised by the shape of the extruded material at extrusion
• CPC Class Codes: B29C 48/252 Drive or actuation means; Transmission means; Screw supporting means
• CPC Class Codes: B29C 48/43 Ring extruders
• CPC Class Codes: B29C 48/435 Sub-screws
• CPC Class Codes: B29K 2021/00 Use of unspecified rubbers as moulding material
• CPC Class Codes: Y10T 74/19084 Spur
• CPC Class Codes: Y10T 74/19135 Spur
• CPC Class Codes: Y10T 74/19219 Interchangeably locked

Abstract

To drive an extruder which has several axially parallel shafts rotating in the same direction, with conveyor elements, arranged around a circle at equal angles with respect to each other, the shafts are attached to the driven shafts of a gear system. Each driven shaft has a pinion, and each driven pinion engages both with an externally-toothed drive wheel and with an internally-toothed hollow gear wheel. The externally-toothed drive wheel and the internally-toothed hollow gear wheel are driven with the same torque.

Claims

1. Gear system to drive an extruder with several axially parallel shafts, rotating in the same direction, arranged around a circle at equal angles with respect to each other, which are attached in a torque-proof manner to conveyor elements, wherewith the conveyor elements of adjacent said axially parallel shafts engage with each other, wherein driven shafts of the gear system are attached coaxially and in a torque-proof manner to the axially parallel shafts, each said driven shaft having an axially offset driven pinion, the driven pinions engaging respectively with an externally-toothed drive wheel provided on a central drive shaft and with a surrounding internally-toothed hollow gear wheel, wherein the respective drive wheel of the central drive shaft and the hollow gear wheel are arranged in similarly offset fashion, wherein the hollow gear wheel has an external tooth gearing, with which an outwardly located drive wheel on an outwardly-located drive shaft engages, so that half of the torque of each said driven pinion is generated via the central drive wheel and half via the hollow gear wheel.

2. Gear system according to claim 1, wherein the outwardly-located drive shaft comprises one of a plurality of short and long outwardly-located drive shafts having different lengths as a result of the axially offset driven pinions of the adjacent driven shafts, and the short outwardly-located drive shafts have a smaller diameter than the long outwardly-located drive shafts.

3. Gear system according to claim 1, wherein at least two said outwardly-located drive wheels are arranged at equal angles with respect to each other and engage with the external tooth gearing of the hollow gear wheel.

4. Gear system according to claim 1, wherein to drive the central drive shaft and the outwardly-located drive shaft, a coaxial floating bush is provided having an internal tooth gearing and an external tooth gearing, wherein the internal tooth gearing engages with an external tooth gearing on the inwardly-located central drive shaft, and wherein the external tooth gearing engages with an internal tooth gearing of a second hollow gear wheel, and external tooth gearing of the second hollow gear wheel engaging, via an axially offset reversing wheel, with a toothed wheel on the outwardly-located drive shaft.

5. Gear system according to claim 4, wherein the external tooth gearing and the internal tooth gearing of the floating bush are formed by skew bevel gearings opposite each other.

6. Gear system according to claim 4, wherein the bush is driven via a straight tooth gearing.

7. Gear system according to claim 1, wherein the axially parallel shafts comprise at least eight said axially parallel shafts rotating in the same direction.

8. Gear system according to claim 1, wherein the hollow gear wheel comprises a first hollow gear wheel driven by said outwardly located drive shaft, and wherein the outwardly located drive shaft comprises a first outwardly located drive shaft, the system including a second hollow gear wheel spaced axially from the first hollow gear wheel, the second hollow gear wheel being driven by a second outwardly-located drive shaft.