Temperature-dependent infinitely variable ratio transmission control system and method
AssigneeGeneral Electronic Company
InventorDavid A. Wallace
Life of this patent
Estimating the term…
Abstract
To prevent overheating of the power system in a vehicle, a control system operates to dynamically adjust the transmission ratio in response to operating temperature so as to establish the degree of engine speed schedule suppression for any given operator speed command requisite to providing maximum possible vehicle performance while maintaining the operating temperature below an unsafe level.
Claims15
A control system for a vehicle equipped with a drive system including an internal combustion engine driving an infinitely variable ratio transmission, said control system comprising, in combination:
- A. a manually operated throttle for generating engine speed commands to the engine;
- B. a first sensor for generating a signal indicative of engine speed;
- C. a transmission controller operatively linked with the transmission, said transmission controller adjusting the transmission ratio in response to said engine speed commands and said engine speed signal to maintain an engine speed schedule corresponding to a given engine speed command;
- D. a temperature sensor monitoring the heat rejected by the drive system, said controller operating in response to said temperature sensor to produce a decrease in engine speed by increasing the transmission ratio when the heat rejected by said drive system reaches an unsafe level and then adjust the transmission ratio to maintain the decrease engine speed as a new engine speed schedule for said given engine speed command.
A method for controlling the speed of an internal combustion engine driving an infinitely variable ratio transmission in a vehicle drive system, said method comprising the steps of:
- A. generating engine speed commands to the engine;
- B. sensing the speed of the engine in response to engine speed commands.
- C. monitoring a temperature indicative of the heat rejected by the vehicle drive system;
- D. adjusting the transmission ratio in response to the engine speed commands and the sensed engine speed to maintain the engine speed normally scheduled for any given engine speed command;
- E. responding to the rejected heat temperature reaching an unsafe level by increasing the transmission ratio to produce a reduction in engine speed;
- and
- F. readjusting the transmission ratio to maintain the reduced engine speed to the new engine speed scheduled for any given engine speed command.
Dependencies are inferred from the claim text.