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US5425335A Expired / Lapsed US ⏱️ 0.0 years remaining

Automobile engine

Assignee: Mitsubishi Motors Corp
•
Filing: 1992-12-25
•
Granted: 1995-06-20
•
Expires: 2012-12-25
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Abstract

Abstract Disclosed is an automobile engine which has different ranges for the partial cylinder operation mode depending upon whether or not the engine is idling. The partial cylinder operation mode is selectable in different operation ranges in response to operating status of an air-conditioner, a power steering switch or a throttle opening sensor. Thus, the engine can reliably assume the partial cylinder operation mode in a wide operation range without stall, thereby accomplishing fuel saving.

Inventors

  • 👤 Katsuhiko Miyamoto
  • 👤 Kazumasa Iida
  • 👤 Tetsuo Chamoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 05:40
CPC Classifications
F; F02; F02D; F02D17/00; F02D17/02; F01; F01L; F01L1/00; F01L1/26; F01L1/267; F02D13/00; F02D13/02; F02D13/06; F02F; F02F7/00; F02F7/006; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 97 words
An automobile engine having a partial cylinder operation mode rendering inoperative some cylinders, comprising: an engine speed sensor for detecting an engine speed; a manifold pressure sensor for providing boost pressure data so as to detect a negative pressure of an intake pipe; and a control unit having a plurality of maps defined by ranges of detected engine speed and boost pressure data for selectively operating the engine in a partial cylinder operation range mode, one of said plurality of maps being selected in response to an output from a load switch for detecting an engine load.
Claim 2
Dependent Claim 97 words
An automobile engine having a partial cylinder operation mode rendering inoperative some cylinders, comprising: an engine speed sensor for detecting an engine speed; a manifold pressure sensor for providing boost pressure data so as to detect a negative pressure of an intake pipe; and a control unit having a plurality of maps defined by ranges of detected engine speed and boost pressure data for selectively operating the engine in a partial cylinder operation range mode, one of said plurality of maps being selected in response to an output from a load switch for detecting an engine load.
Claim 3
Dependent Claim 14 words
The automobile engine of claim 1, wherein the load switch is an idle switch.
Claim 4
Dependent Claim 26 words
The automobile engine of claim 2, wherein an engine speed for rendering inoperative some cylinders is higher during an idling state than during a non-idling state.
Claim 5
Dependent Claim 102 words
The automobile engine of claim 3, wherein the plurality of maps includes a first map in which the partial cylinder operation mode range is set in a manner such that the volumetric efficiency is gradually increased between a desired low speed range and a desired intermediate speed range during the non-idling operation, and a second map in which the partial cylinder operation mode range is set in manner such that the volumetric efficiency is decreased between a desired idle speed and a desired low speed range and is then increased between the desired low speed range and a desired intermediate speed range.
Claim 6
Dependent Claim 14 words
The automobile engine of claims 1, wherein the load switch is an air-conditioner switch.
Claim 7
Dependent Claim 15 words
The automobile engine of claims 1, wherein the load switch is a power steering switch.
Claim 8
Dependent Claim 15 words
The automobile engine of claims 1, wherein the load switch is a throttle opening sensor.
Claim 9
Dependent Claim 32 words
The automobile engine of claim 7, wherein the partial cylinder operation mode is canceled when a variation of the throttle opening detected by the throttle opening sensor is above a predetermined value.
Claim 10
Dependent Claim 24 words
The automobile engine of claim 1, wherein one of said plurality of maps momentarily increases the volumetric efficiency when the engine speed is low.
Claim 11
Dependent Claim 47 words
The automobile engine of claim 9, wherein one of said plurality of maps decreases the volumetric efficiency between a desired idle speed and a desired low speed range but then gradually increases the volumetric efficiency between the desired low speed range and a desired intermediate speed range.
Claim 12
Dependent Claim 40 words
The automobile engine of claim 1, wherein the control unit cancels the partial cylinder operation mode when it detects the idling, and one of the actuation of an air-conditioner, the actuation of a power steering, and an abnormal engine speed.
Claim 13
Dependent Claim 32 words
The automobile engine of claim 11, wherein the control unit inhibits the partial cylinder operation mode for a preset period of time after detecting non-actuation of the air-conditioner and the power steering.
Claim 14
Dependent Claim 43 words
The automobile engine of claim 12, wherein during the actuation of the air-conditioner in the partial cylinder operation mode, an engine output is set to be larger than the engine output during the non-actuation of the air-conditioner in the partial cylinder operation mode.
Claim 15
Dependent Claim 45 words
The automobile engine of claim 12, wherein during the actuation of the power steering in the partial cylinder operation mode, an engine output is set to be larger than the engine output during the non-actuation of the power steering in the partial cylinder operation mode.
Claim 16
Dependent Claim 25 words
The automobile engine of claim 1, wherein the control unit inhibits the partial cylinder operation mode when an engine speed is below a predetermined value.
Claim 17
Dependent Claim 31 words
The automobile engine of claim 1, wherein the control unit varies the partial cylinder operation range depending upon the actuation or non-actuation of the air-conditioner when the engine is not idling.
Claim 18
Dependent Claim 35 words
The automobile engine of claim 16, wherein during the actuation of the air-conditioner, the control unit sets a lowest engine speed to be higher than a lowest engine speed during the non-actuation of the air-conditioner.
Claim 19
Dependent Claim 110 words
The automobile engine of claim 17, wherein the control unit includes a map in which the partial cylinder operation mode range is set in a manner such that the volumetric efficiency is gradually increased between a desired low speed range and a desired intermediate speed range during the actuation of the air-conditioner, and a third map in which the partial cylinder operation mode range is set in a manner such that the volumetric efficiency is decreased between a desired idle speed range between a desired low speed range and is then increased between the desired low speed range and a desired intermediate speed range during the non-actuation of the air-conditioner.
Claim 20
Dependent Claim 44 words
The automobile engine of claim 1, wherein the control unit inhibits for a preset period of time the full cylinder operation mode from being switched over to the partial cylinder operation mode even when the engine becomes ready for the partial cylinder operation mode.
Claim 21
Dependent Claim 24 words
The automobile engine of claim 19, wherein the preset period of time for inhibiting the switchover is lengthened as the engine speed becomes lower.
Claim 22
Dependent Claim 44 words
The automobile engine of claim 1, wherein the control unit inhibits for a preset period of time the partial cylinder operation mode from being switched over to the full cylinder operation mode even when the engine gets ready for the full cylinder operation mode.
Claim 23
Dependent Claim 24 words
The automobile engine of claim 21, wherein the preset period of time for inhibiting the switchover is lengthened as the engine speed becomes lower.
Claim 24
Dependent Claim 55 words
The automobile engine of claim 1, wherein the control unit sets the period of time for inhibiting the switchover of the partial cylinder operation mode to the full cylinder operation mode to be shorter than the period of time for inhibiting the switchover of the full cylinder operation mode to the partial cylinder operation mode.

References Cited (Backward Citations)

US4274382A Cited
JPS58135336A Cited
JPS5951144A Cited
JPS5963338A Cited
US4459960A Cited
US4608952A Cited
JPH03213604A Cited
US5105779A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-06-19 1998-12-19 1999-06-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-06-19 2002-12-19 2003-06-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-06-19 2006-12-19 2007-06-20 $7700.00 Window Closed / Lapsed

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