Computer controllable 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. 6 figs.
- Inventors:
- Issue Date:
- Research Org.:
- Ford Motor Company, Detroit, MI (United States)
- OSTI Identifier:
- 7168173
- Patent Number(s):
- 4855914
- Application Number:
- PPN: US 7-126064
- Assignee:
- IDO; EDB-94-116114
- DOE Contract Number:
- AC07-85NV10418
- Resource Type:
- Patent
- Resource Relation:
- Patent File Date: 27 Nov 1987
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 33 ADVANCED PROPULSION SYSTEMS; MECHANICAL TRANSMISSIONS; COMPUTERIZED CONTROL SYSTEMS; VEHICLES; MONITORS; OPERATION; REGENERATIVE BRAKING; CONTROL SYSTEMS; MACHINE PARTS; MEASURING INSTRUMENTS; ON-LINE CONTROL SYSTEMS; ON-LINE SYSTEMS; 330602* - Vehicle Design Factors- Engine-Transmission Matching
Citation Formats
Davis, R I, and Patil, P B. Computer controllable synchronous shifting of an automatic transmission. United States: N. p., 1989.
Web.
Davis, R I, & Patil, P B. Computer controllable synchronous shifting of an automatic transmission. United States.
Davis, R I, and Patil, P B. Tue .
"Computer controllable synchronous shifting of an automatic transmission". United States.
@article{osti_7168173,
title = {Computer controllable synchronous shifting of an automatic transmission},
author = {Davis, R I and Patil, P 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. 6 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1989},
month = {8}
}