Hydraulic accumulator temperature estimation for controlling automatic engine stop/start
AssigneeGM Global Technology Operations LLC
InventorPaul G. Otanez
Life of this patent
Estimating the term…
Abstract
A method of preventing an automatic engine stop includes estimating a temperature of a volume of fluid within a hydraulic accumulator that is in selective fluid communication with a fluidly-actuated torque-transmitting device. The torque-transmitting device is coupled to an internal combustion engine and configured to selectively transmit a torque from the engine to a vehicle wheel. The method further includes comparing the estimated fluid temperature to a temperature range, and preventing the internal combustion engine from automatically stopping if the estimated fluid temperature is outside of the temperature range.
Claims14
A method of preventing an automatic engine stop comprising:
- estimating a temperature of a volume of fluid within a hydraulic accumulator, wherein the hydraulic accumulator is in selective fluid communication with a fluidly-actuated torque-transmitting device coupled to an internal combustion engine;
- comparing the estimated fluid temperature to a temperature range;
- and
- preventing the internal combustion engine from automatically stopping if the estimated fluid temperature is outside of the temperature range.
A vehicle comprising:
- an internal combustion engine configured to combust a fuel to provide a mechanical rotary output, and automatically stop combusting the fuel if vehicle motion is prevented by a braking device;
- a transmission coupled with the internal combustion engine and including a fluidly actuated torque transmitting device configured to selectively transmit the rotary output of the internal combustion engine to a vehicle wheel;
- a hydraulic control system in fluid communication with the torque transmitting device, the hydraulic control system including a fluid circuit in fluid communication with a fluid sump and a hydraulic accumulator, wherein the hydraulic accumulator is configured to selectively retain a volume of fluid;
- a control module in communication with the hydraulic control system and with the internal combustion engine, the control module configured to:
- estimate a temperature of the volume of fluid within a hydraulic accumulator;
- compare the estimated fluid temperature to a temperature range;
- and
- prevent the internal combustion engine from automatically stopping if the estimated fluid temperature is outside of the temperature range.
A vehicle comprising:
- an internal combustion engine configured to combust a fuel to provide a mechanical rotary output, and automatically stop combusting the fuel if a vehicle motion is prevented by a braking device;
- a transmission coupled with the internal combustion engine and including a fluidly actuated torque transmitting device configured to selectively transmit the rotary output of the internal combustion engine to a vehicle wheel;
- a hydraulic control system in fluid communication with the torque transmitting device, the hydraulic control system including a fluid circuit in fluid communication with a fluid sump and a hydraulic accumulator, wherein the hydraulic accumulator is configured to selectively retain a volume of fluid;
- a control module in communication with the hydraulic control system and with the internal combustion engine, the control module configured to:
- maintain an estimate of a temperature of the volume of fluid within the hydraulic accumulator;
- estimate a change in the temperature of the volume of fluid within a hydraulic accumulator using the estimate of a temperature of the volume of fluid, an ambient temperature, and a temperature of a fluid within the fluid sump;
- update the estimate of temperature of the volume of fluid with the estimated change in temperature;
- compare the updated estimated fluid temperature to a temperature range;
- and
- prevent the internal combustion engine from automatically stopping if the estimated fluid temperature is outside of the temperature range.
Dependencies are inferred from the claim text.