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Title: Computer controlled synchronous shifting of an automatic transmission

Abstract

A multiple forward speed automatic transmission produces its lowest forward speed ratio when a hydraulic clutch and hydraulic brake are disengaged and a one-way clutch connects a ring gear to the transmission casing. Second forward speed ratio results when the hydraulic clutch is engaged to connect the ring gear to the planetary carrier of a second gear set. Reverse drive and regenerative operation result when an hydraulic brake fixes the planetary and the direction of power flow is reversed. Various sensors produce signals representing the torque at the output of the transmission or drive wheels, the speed of the power source, and the hydraulic pressure applied to a clutch and brake. A control algorithm produces input data representing a commanded upshift, a commanded downshift, a commanded transmission output torque, and commanded power source speed. A microprocessor processes the inputs and produces a response to them in accordance with the execution of a control algorithm. Output or response signals cause selective engagement and disengagement of the clutch and brake at a rate that satisfies the requirements for a short gear ratio change and smooth torque transfer between the friction elements.

Inventors:
 [1];  [2]
  1. 9214 Abbey La., Ypsilanti, MI 48198
  2. 10294 W. Outer Dr., Detroit, MI 48223
Issue Date:
Research Org.:
Ford Motor Company, Detroit, MI (United States)
OSTI Identifier:
867071
Patent Number(s):
4855914
Assignee:
Davis, Roy I. (9214 Abbey La., Ypsilanti, MI 48198);Patil, Prabhakar B. (10294 W. Outer Dr., Detroit, MI 48223)
Patent Classifications (CPCs):
Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10T - TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
F - MECHANICAL ENGINEERING F16 - ENGINEERING ELEMENTS AND UNITS F16H - GEARING
DOE Contract Number:  
AC07-85NV10418
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
computer; controlled; synchronous; shifting; automatic; transmission; multiple; forward; speed; produces; lowest; ratio; hydraulic; clutch; brake; disengaged; one-way; connects; gear; casing; results; engaged; connect; planetary; carrier; set; reverse; drive; regenerative; operation; result; fixes; direction; power; flow; reversed; various; sensors; produce; signals; representing; torque; output; wheels; source; pressure; applied; control; algorithm; input; data; commanded; upshift; downshift; microprocessor; processes; inputs; response; accordance; execution; selective; engagement; disengagement; rate; satisfies; requirements; change; smooth; transfer; friction; elements; response signal; output torque; signals representing; speed ratio; drive wheels; forward speed; control algorithm; ratio change; automatic transmission; hydraulic pressure; computer controlled; power source; gear set; drive wheel; data representing; commanded power; pressure applied; input data; computer control; ratio results; transmission output; source speed; produce signals; reverse drive; various sensors; hydraulic clutch; hydraulic brake; power flow; clutch connects; operation result; one-way clutch; multiple forward; gear ratio; speed automatic; transmission produces; various sensor; lowest forward; /701/477/

Citation Formats

Davis, Roy I, and Patil, Prabhakar B. Computer controlled synchronous shifting of an automatic transmission. United States: N. p., 1989. Web.
Davis, Roy I, & Patil, Prabhakar B. Computer controlled synchronous shifting of an automatic transmission. United States.
Davis, Roy I, and Patil, Prabhakar B. Sun . "Computer controlled synchronous shifting of an automatic transmission". United States. https://www.osti.gov/servlets/purl/867071.
@article{osti_867071,
title = {Computer controlled synchronous shifting of an automatic transmission},
author = {Davis, Roy I and Patil, Prabhakar B},
abstractNote = {A multiple forward speed automatic transmission produces its lowest forward speed ratio when a hydraulic clutch and hydraulic brake are disengaged and a one-way clutch connects a ring gear to the transmission casing. Second forward speed ratio results when the hydraulic clutch is engaged to connect the ring gear to the planetary carrier of a second gear set. Reverse drive and regenerative operation result when an hydraulic brake fixes the planetary and the direction of power flow is reversed. Various sensors produce signals representing the torque at the output of the transmission or drive wheels, the speed of the power source, and the hydraulic pressure applied to a clutch and brake. A control algorithm produces input data representing a commanded upshift, a commanded downshift, a commanded transmission output torque, and commanded power source speed. A microprocessor processes the inputs and produces a response to them in accordance with the execution of a control algorithm. Output or response signals cause selective engagement and disengagement of the clutch and brake at a rate that satisfies the requirements for a short gear ratio change and smooth torque transfer between the friction elements.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1989},
month = {1}
}