AUTOMATIC TRANSMISSION SHIFTING POINT AND FIRMNESS VARIATION CONTROL

• US 3,827,315 A
• Filed: 01/23/1973
• Issued: 08/06/1974
• Est. Priority Date: 01/23/1973
• Status: Expired due to Term

• Current Assignee: Joseph Paul Lupo
• Original Assignee: Joseph Paul Lupo
• Inventors: Lupo, Joseph Paul
• Primary Examiner(s): Gerin, Leonard H.
• Application Number:
  US05/326,053
• Time in Patent Office: 560 Days
• Field of Search: 74/863
• US Class Current: 477/121
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2540/215 Selection or confirmation of options
• CPC Class Codes: B60W 30/182 Selecting between different operative modes, e.g. comfort and performance modes
• CPC Class Codes: B60W 30/19 Improvement of gear change, e.g. by synchronisation or smoothing gear shift

Abstract

A method and system providing variable vehicle operator control of the shift points and shifting firmness of a stock automatic transmission to obtain high-performance shifting without mechanical modification of the transmission by intercepting the transmission input torque signal to the transmission hydraulic control system and modifying it to be unrepresentative of actual vehicle engine torque and carburetor opening. Particular suitability is achieved with automatic transmissions having an engine vacuum signal responsive modulator valve.

Claims

1. A method of obtaining high-performance shifting in a vehicle automatic transmission having a hydraulic control system by variably controlling the shift point and firmness of the shift of the automatic transmission comprising intercepting the transmission input torque signal to the transmission hydraulic control system, controllably modifying the signal so that it is not representative, under the normal operating design conditions, of vehicle engine torque and carburetor opening, and increasing the transmission hydraulic control line pressure in order that the normal transmission shift point is delayed and the shifting firmness increased.

2. A method as claimed in claim 1, wherein the automatic transmission has an engine vacuum responsive modulator valve and interception and modification of the transmission input torque signal comprises positioning an adjustable valve in the vacuum line which transmits the engine vacuum signal to the vacuum responsive modulator valve and controlling the adjustment of the valve so that vacuum signal is modified to be unrepresentative.

3. A vehicle automatic transmission system including a hydraulic control system responsive to a transmission input torque signal, a source of a vacuum signal normally representative of vehicle engine torque and carburetor opening, a vacuum signal responsive modulator valve and a vacuum line which transmits the vacuum signal to the modulator valve, wherein the improvement comprises a valve body passageway positioned in the vacuum line, a hand actuatable valve plug operatively associated with the valve body and controllably movable to adjustably open or close the valve body passageway and intercept and controllably modify the the vacuum signal so that it is not representative, under normal operating design conditions, of vehicle engine torque and carburetor opening, whereby the hydraulic control system line pressure is increased in order that the normal transmission shift point is delayed and the shifting firmness increased without mechanical modification of the automatic transmission itself.

4. A system as claimed in claim 3, wherein the hand actuable valve plug is located within the vehicle operatoR compartment and is controllably adjustable from an open position permitting the normally representative vacuum signal to reach the vacuum modulator to one blocking the signal entirely.