US 12,152,727 B2
Oil temperature estimation apparatus and oil temperature estimation method
Ryusei Wada, Tokyo (JP); Taishi Kobayashi, Tokyo (JP); and Junji Harada, Tokyo (JP)
Assigned to SUBARU CORPORATION, Tokyo (JP)
Filed by SUBARU CORPORATION, Tokyo (JP)
Filed on May 22, 2023, as Appl. No. 18/200,176.
Claims priority of application No. 2022-088438 (JP), filed on May 31, 2022.
Prior Publication US 2023/0383905 A1, Nov. 30, 2023
Int. Cl. F16N 29/00 (2006.01); F16H 59/44 (2006.01); F16H 59/64 (2006.01); F16H 59/74 (2006.01)
CPC F16N 29/00 (2013.01) [F16H 59/44 (2013.01); F16H 59/64 (2013.01); F16H 59/74 (2013.01); F16N 2210/04 (2013.01); F16N 2250/11 (2013.01)] 9 Claims
OG exemplary drawing
 
1. An oil temperature estimation apparatus configured to estimate an oil temperature and perform high temperature protection of a driving system of a vehicle, the oil temperature estimation apparatus comprising:
a vehicle speed sensor configured to detect a vehicle speed of the vehicle;
an outside air temperature sensor configured to detect an outside air temperature;
one or more processors and one or more memories storing instructions configured to cause the one or more processors to:
acquire an estimated oil temperature initial value;
use, at a start of estimating the oil temperature, the estimated oil temperature initial value as an estimated oil temperature previous value;
acquire a saturated oil temperature in a running state of the vehicle based on the running state and on the outside air temperature, the running state at least including the vehicle speed;
acquire an oil temperature deviation between the saturated oil temperature and the estimated oil temperature previous value;
acquire an oil temperature feedback value based on the oil temperature deviation and the vehicle speed;
acquire an estimated oil temperature current value based on the estimated oil temperature previous value and the oil temperature feedback value, the estimated oil temperature current value including a current value of the estimated oil temperature that is estimated one time after the last value of the estimated oil temperature, wherein the estimated oil temperature current value is used as the estimated oil temperature previous value one time after the current value of the estimated temperature in a next estimation of the oil temperature; and
in response to the estimated oil temperature current value being higher than or equal to a predetermined value, restrict the vehicle speed of the vehicle.