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US4640245A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of controlling an engine mounted on a construction vehicle

Assignee: Komatsu Ltd
•
Filing: 1985-05-28
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Granted: 1987-02-03
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Expires: 2005-05-28
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Abstract

Abstract A method of controlling an engine mounted on a construction vehicle comprising the steps of reducing the rotation of the engine to a primary number of revolutions per minute, which is in the vicinity of the rated number of revolutions per minute of the engine under earth moving operation conditions, immediately after all operating levers associated with all of the control valves for turning the vehicle body, for actuating work implements and for running of the vehicle are shifted to their neutral positions, maintaining the engine under such a low speed running condition for a predetermined period of time, and then reducing further the rotation of the engine to a lower, secondary number of revolutions per minute which corresponds to the number of revolutions per minute under idle running conditions thereby achieving reduction in fuel consumption and level of noise generated by the engine.

Inventors

  • 👤 Yukinobu Matsuda
  • 👤 Takayasu Inui

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 06:32
CPC Classifications
F; F02; F02D; F02D31/00; F02D29/00; F02D29/04; E; E02; E02F; E02F9/00; E02F9/20; E02F9/22; E02F9/2246

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 121 words
The method of controlling an engine mounted on a construction vehicle used for earth moving operations and including operating levers associated with control valves for work implements and a control system, said operating levers having operating positions and neutral positions, said method comprising the steps of: reducing the rotational speed of the engine to a primary number of revolutions per minute immediately after all said operating levers associated with all control valves for work implements and the control system are shifted to their respective neutral positions; maintaining the engine under such a low speed running condition for a predetermined period of time; and then reducing further the rotational speed of the engine to a lower, secondary number of revolutions per minute.
Claim 2
Independent Claim 121 words
The method of controlling an engine mounted on a construction vehicle used for earth moving operations and including operating levers associated with control valves for work implements and a control system, said operating levers having operating positions and neutral positions, said method comprising the steps of: reducing the rotational speed of the engine to a primary number of revolutions per minute immediately after all said operating levers associated with all control valves for work implements and the control system are shifted to their respective neutral positions; maintaining the engine under such a low speed running condition for a predetermined period of time; and then reducing further the rotational speed of the engine to a lower, secondary number of revolutions per minute.
Claim 3
Dependent Claim 67 words
The method of controlling an engine mounted on a construction vehicle as claimed in claim 1, wherein said primary number of revolutions per minute is in the vicinity of the rated number of revolutions per minute of the engine under earth moving operation conditions and is at such a level that change in the rotational speed of the engine has no influence on the earth moving operation.
Claim 4
Dependent Claim 38 words
The method of controlling an engine mounted on a construction vehicle as claimed in claim 1, wherein said secondary number of revolutions per minute is the number of revolutions per minute of the engine under idle running condition.
Claim 5
Dependent Claim 34 words
The method of controlling an engine mounted on a construction vehicle as claimed in claim 1, wherein the duration of said primary number of revolutions is in the range of three to four seconds.

References Cited (Backward Citations)

US3982508A Cited
US4124095A Cited
US4479472A Cited
DE3134068A1 Cited
US4545449A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-02-02 1990-08-04 1991-02-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-02-02 1994-08-04 1995-02-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-02-02 1998-08-04 1999-02-03 $7700.00 Window Closed / Lapsed

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