US 12,173,784 B2
Oil shortage determining system
Yosuke Kato, Nisshin (JP)
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed by TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed on Feb. 11, 2022, as Appl. No. 17/650,746.
Claims priority of application No. 2021-024473 (JP), filed on Feb. 18, 2021.
Prior Publication US 2022/0260151 A1, Aug. 18, 2022
Int. Cl. F16H 57/04 (2010.01)
CPC F16H 57/0449 (2013.01) [F16H 57/0412 (2013.01)] 7 Claims
OG exemplary drawing
 
1. An oil shortage determining system comprising:
a motor serving as a driving source of a vehicle;
a power transmission mechanism configured to transmit power of the motor to a drive wheel of the vehicle;
an oil circulation mechanism configured to circulate oil for cooling the power transmission mechanism and the motor;
a first temperature sensor configured to detect a temperature of the motor;
a second temperature sensor configured to detect a temperature of the oil; and
a determining device configured to determine whether there is a shortage of the oil, wherein:
the determining device is configured to execute
an acquisition process of acquiring a temperature of the motor and a temperature of the oil, and
a determining process of determining whether there is a shortage of the oil based on the temperature of the motor and the temperature of the oil;
in the determining process, the determining device is configured to determine that the oil is short when the temperature of the motor is higher than the temperature of the oil and a difference between the temperature of the motor and the temperature of the oil is greater than a predetermined prescribed value;
where a duration from when an ignition switch of the vehicle is turned on to when the ignition switch is turned off is one trip;
the determining device is configured to, when the temperature of the oil to be acquired in the initial acquisition process of each trip is lower than or equal to a predetermined threshold, prohibit a determination that the oil is short in the determining process until the trip ends; and
the determining device is configured to, when the temperature of the oil to be acquired in the initial acquisition process of each trip is higher than the threshold, execute the determining process without prohibiting a determination that the oil is short until the trip ends.