Gm Global Technolgoy Operations, Inc.

Allison Transmission, Inc.

Thomas H Wilson

Charles Francis Long

Travis A Brown

Phillip F McCauley

William M Murray

Darren J Weber

Ronald A Lee

Linus L Happ

Rebecca Lynn Schenk

Joshua Gilberg

Robert T Niemczyk

A method, apparatus and system for controlling transmission clutch system output pressures is provided. A transmission control unit and a pressure control device including an electro-hydraulic valve and a pressure switch cooperate to provide self-calibrating clutch pressure control systems.

Method and apparatus for clutch pressure control

A vehicle performance system and method for determining and displaying vehicle performance data includes a display device in communication with a transmission controller, an engine controller, and a plurality of vehicle condition sensors. The transmission controller calculates vehicle performance data from data signals sent by the plurality of vehicle condition sensors and from stored performance maps. The display device communicates the vehicle performance data to a user of the vehicle performance system.

Motor vehicle performance monitoring system and method

A method, apparatus and system for controlling transmission clutch and/or variator system pressures is provided. A transmission control unit and a pressure control device including an electro-hydraulic valve and a pressure switch cooperate to provide self-calibrating clutch and/or variator pressure control systems.

A system for calibrating an input electrical signal to an individual pressure control device includes the steps of providing a target pressure-to-current (P/I) threshold, providing a lower estimated P/I threshold, and providing an estimated P/I curve that passes between the target P/I threshold and the lower estimated P/I threshold. Next, the method determines a lower actual P/I threshold at a pressure equal to the pressure at the lower estimated P/I threshold. A maximum offset current is calculated from the difference between the currents at the lower actual P/I threshold and the lower estimated P/I threshold. Finally, the system calculates a calibrated P/I curve. The calibrated P/I curve includes the target P/I threshold and the lower actual P/I threshold. The slope of the calibrated P/I curve is calculated as a proportional value of the maximum offset current.

System and method for controlling solenoid pressure

A shift selector apparatus is provided. The apparatus includes a first operational zone and a second operational zone. The apparatus provides separation between the two operational zones to prevent accidental shifting between ranges.

Shift selector apparatus

A method for calibrating an input electrical signal to an individual pressure control device includes the steps of providing a target pressure-to-current (P/I) threshold, providing a lower estimated P/I threshold, and providing an estimated P/I curve that passes between the target P/I threshold and the lower estimated P/I threshold. Next, the method determines a lower actual P/I threshold at a pressure equal to the pressure at the lower estimated P/I threshold. A maximum offset current is calculated from the difference between the currents at the lower actual P/I threshold and the lower estimated P/I threshold. Finally, the method calculates a calibrated P/I curve. The calibrated P/I curve includes the target P/I threshold and the lower actual P/I threshold. The slope of the calibrated P/I curve is calculated as a proportional value of the maximum offset current.

Method for controlling solenoid pressure

The present invention provides a solenoid and electrical connector assembly which includes a solenoid body having a pair of electrical terminals disposed on opposite sides of a plunger component and a connector having two corresponding electrical terminals and a non-conductive blade or tongue disposed therebetween. When assembled, the tongue of the connector seats between the terminals on the solenoid body and inhibits corrosion and ingress of foreign matter in the region between the terminals of the solenoid.

Solenoid and connector assembly

Shift control valves for controlling the engagement of a transmission friction devices have a solenoid control chamber pressurized to initiate shifting and a latch chamber pressurized to sustain the selective friction device in an engaged position. The latching chamber pressure is delivered through a latch valve which is also solenoid controlled to direct pressure to the chamber when the solenoid is de-energized and to exhaust the latch chamber when the solenoid is energized.

Transmission control valves

An engagement control valve for a fluid operated torque transmitter, such as a clutch, has a pulse width modulated (PWM) solenoid, a valve spool and an accumulator. The PWM solenoid supplies control pressure through a flow restrictor to a control chamber adjacent one end of the valve spool which responds by establishing a proportionate engagement pressure for the torque transmitter. The accumulator has a piston slidably disposed in the valve spool, adjacent the control chamber, for fluid communication with the control pressure from the PWM solenoid. A damping chamber is formed adjacent the other end of the valve spool and is in fluid communication with an exhaust port via a flow restrictor.

Control valve with integral accumulator

An apparatus and technique for fluid level determination in automatic transmissions. The invention employs an electronic control unit in association with an automatic transmission for a vehicle, the electronic control unit receiving data corresponding to transmission oil level, transmission oil temperature, engine speed, transmission speed, and transmission selected range. Upon determining that such data satisfies certain diagnostic tests, the level of transmission fluid within the transmission is determined and adjusted or otherwise normalized to ideal test conditions. The electronic control unit compensates an oil level signal for deviations in oil temperature from an optimum test temperature, and makes further compensation for deviations in engine speed and settling time at the time that the test data is acquired. Additionally, variations in oil density as a function of oil temperature are also compensated.

Apparatus and technique for fluid level determination in automatic

A single capacitor is used to measure the oil level in an engine or transmission and compensate the sensed capacitance for changes in dielectric constant. Measurements are made for two different running conditions, one giving a capacitance reading dependent only on dielectric constant and one giving a capacitance dependent on oil level as well as dielectric constant. The transmission application uses a capacitor that is fully immersed in oil when the engine is off and partly immersed when the engine is idling, so that both types of measurements can be obtained. The engine application uses a capacitor having an upper section spaced from a lower section. Only the lower section is immersed during engine idle to render dielectric constant information, while the upper section is partly immersed when the engine is off.

Growing community of inventors

Indianapolis, IN, United States of America

Thomas H Wilson