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US4616530A Expired / Lapsed US ⏱️ 0.0 years remaining

Hydraulic control system for automatic transmission such as a continuously variable transmission

Assignee: Nissan Motor Co Ltd
•
Filing: 1984-01-27
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Granted: 1986-10-14
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Expires: 2004-01-27
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Abstract

Abstract A hydraulic control system is provided wherein a predetermined delay is provided by controlling the flow of fluid from or to frictional element which contributes to shifting into a neutral state within the transmission. With this delay, the engine can sustain rotational speed necessary for restarting upon resumption of fuel supply even after the manual valve is shifted to the neutral state during running condition of an automotive vehicle where the fuel supply to the engine is interrupted.

Inventors

  • 👤 Yoshikazu Tanaka
  • 👤 Haruyoshi Kumura
  • 👤 Keiju Abo
  • 👤 Sigeaki Yamamuro
  • 👤 Hiroyuki Hirano

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 05:22
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/66; F16H61/662; F16H61/66254; F16H61/66259; F16D; F16D48/00; F16D48/02; F16D48/0206; F16H61/02; F16H61/0262; F16H61/0276; F16H61/0286; F16D2500/00; F16D2500/10; F16D2500/104; F16D2500/10406; F16D2500/10412; F16D2500/108; F16D2500/1081; F16D2500/1085; F16D2500/1088; F16D2500/30; F16D2500/306; F16D2500/3067; F16D2500/316; F16D2500/3166; F16D2500/50; F16D2500/504; F16D2500/5043; F16H61/04; F16H2061/0485

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 240 words
In an automotive vehicle having driven wheels: an engine; a transmission having an input member drivingly connected with the engine and an output member drivingly connected with the driven wheels, the transmission including frictional element means for interrupting a power delivery path between the engine and the driven wheels; a source of pressurized fluid; a manual valve communicating with said source of pressurized fluid and the frictional element means, said manual valve being shiftable to a forward drive position wherein said manual valve establishes a fluid feed line through which the pressurized fluid is supplied to the frictional element means from said source of pressurized fluid, a neutral position wherein said manual valve establishes a drain fluid line through which the pressurized fluid is discharged from the frictional element means, and a reverse drive position; means for delaying a shift to neutral in the transmission when said manual valve is moved to the neutral position from the forward drive position; and fuel cut control means for interrupting the supply of fuel to said engine as long as the engine speed is higher than a first predetermined value after a predetermined operating state of the automotive vehicle has been established and until the enginge speed drops to a second predetermined value that is lower than said first predetermined value, and allowing the resumption of the supply of fuel to said engine when said manual valve is shifted to the neutral position.
Claim 2
Dependent Claim 240 words
In an automotive vehicle having driven wheels: an engine; a transmission having an input member drivingly connected with the engine and an output member drivingly connected with the driven wheels, the transmission including frictional element means for interrupting a power delivery path between the engine and the driven wheels; a source of pressurized fluid; a manual valve communicating with said source of pressurized fluid and the frictional element means, said manual valve being shiftable to a forward drive position wherein said manual valve establishes a fluid feed line through which the pressurized fluid is supplied to the frictional element means from said source of pressurized fluid, a neutral position wherein said manual valve establishes a drain fluid line through which the pressurized fluid is discharged from the frictional element means, and a reverse drive position; means for delaying a shift to neutral in the transmission when said manual valve is moved to the neutral position from the forward drive position; and fuel cut control means for interrupting the supply of fuel to said engine as long as the engine speed is higher than a first predetermined value after a predetermined operating state of the automotive vehicle has been established and until the enginge speed drops to a second predetermined value that is lower than said first predetermined value, and allowing the resumption of the supply of fuel to said engine when said manual valve is shifted to the neutral position.
Claim 3
Dependent Claim 21 words
An automotive vehicle as claimed in claim 1, wherein said delaying means is in the form of a flow control device.
Claim 4
Dependent Claim 44 words
An automotive vehicle as claimed in claim 2, wherein said manual valve includes a spool having a land formed with a cutout portion serving as said flow control device when said manual valve is shifted from the forward drive position to the neutral position.
Claim 5
Dependent Claim 59 words
An automotive vehicle as claimed in claim 2, wherein said flow control device is in the form of a one-way orifice device fluidly disposed between said manual valve and the frictional element means and so arranged as to provide a throttling effect on the flow of hydraulic fluid when the pressurized fluid is discharged from said frictional element means.
Claim 6
Dependent Claim 28 words
An automotive vehicle as claimed in claim 1 wherein said delaying means produces a delay only during a shift from the forward drive position to the neutral position.

References Cited (Backward Citations)

DE2004004A1 Cited
US3703110A Cited
US3922933A Cited
JPS542339A Cited
US4221193A Cited
US4273009A Cited
US4418587A Cited
US4458560A Cited
US4533340A Cited
US4542665A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-10-13 1990-04-14 1990-10-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-10-13 1994-04-14 1994-10-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-10-13 1998-04-14 1998-10-14 $7700.00 Window Closed / Lapsed

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