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US4718771A Expired / Lapsed US ⏱️ 0.0 years remaining

Closed mixing machine

Assignee: Kobe Steel Ltd
•
Filing: 1986-08-15
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Granted: 1988-01-12
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Expires: 2006-08-15
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Abstract

Abstract A closed mixing machine suitable for mixing rubber materials, which includes a closed mixing chamber and a pair of rotors received in the chamber for rotating in opposite directions, wheren the rotor tips' clearance and the rotor rotation speed are increased up to values greater than typical values of the conventional mixing machine. Accoridng to this arrangement, mixing productivity is increased by a maximum of 70% with the even discharge temperature and energy consumption is reduced in comparison with the conventional machine.

Inventors

  • 👤 Toshihiro Asai
  • 👤 Katsunobu Hagiwara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 14:20
CPC Classifications
B; B29; B29B; B29B7/00; B29B7/02; B29B7/06; B29B7/10; B29B7/18; B29B7/183; B29B7/186; B29B7/74; B29B7/7476; B29B7/7495

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 167 words
A closed mixing machine, comprising: a closed mixing chamber formed by a casing and a pair of end frames; a pair of rotors disposed in parallel in the mixing chamber for rotating in opposite directions with respect to each other, each said rotor having at least one longer vane and at least one shorter vane, wherein a ratio α of a tip clearance ho to a rotor diameter R[(=ho/R)] is represented by the relationship 0.015<α<0.04, a rotation speed of said rotors is 70-250 rpm, a rotation speed ratio of one of said rotors to the remaining rotor is 1.0-1.2, a rotor length/diameter ratio is 1.2-2.2, a rotor inclusion angle is 15°-35°, a rotor vane length ratio Ls/Ll is 0.1-0.48, a helix angle θl is 20°-45°, and helix angle θs is 0°-45° wherein Ls is the length of the shorter vane, Ll is the length of the longer vane, θs is the helix angle of the shorter vane, and θl is the helix angle of the longer vane.
Claim 2
Dependent Claim 167 words
A closed mixing machine, comprising: a closed mixing chamber formed by a casing and a pair of end frames; a pair of rotors disposed in parallel in the mixing chamber for rotating in opposite directions with respect to each other, each said rotor having at least one longer vane and at least one shorter vane, wherein a ratio α of a tip clearance ho to a rotor diameter R[(=ho/R)] is represented by the relationship 0.015<α<0.04, a rotation speed of said rotors is 70-250 rpm, a rotation speed ratio of one of said rotors to the remaining rotor is 1.0-1.2, a rotor length/diameter ratio is 1.2-2.2, a rotor inclusion angle is 15°-35°, a rotor vane length ratio Ls/Ll is 0.1-0.48, a helix angle θl is 20°-45°, and helix angle θs is 0°-45° wherein Ls is the length of the shorter vane, Ll is the length of the longer vane, θs is the helix angle of the shorter vane, and θl is the helix angle of the longer vane.

References Cited (Backward Citations)

US4113822A Cited
US4284358A Cited
US4300838A Cited
US4456381A Cited
US4474475A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-01-11 1991-07-13 1992-01-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-01-11 1995-07-13 1996-01-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-01-11 1999-07-13 2000-01-12 $7700.00 Window Closed / Lapsed

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