# US 12,771,209 B2 · Drive device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,771,209 B2 - Document ID: US12771209B2 - Status: Granted - Kind: B2 - Application number: 18/741,477 - Filed: 2024-06-12 - Published: 2024-12-26 - Granted: 2026-10-20 - Earliest claimed: 2023-06-20 - Assignees: Toyota Jidosha Kabushiki Kaisha - Applicants: Toyota Jidosha Kabushiki Kaisha - Inventors: Nobuhito Mori - Web page: https://patentgrep.com/patent/US12771209B2 ## CPC - H02K 9/193: with provision for replenishing the cooling medium; with means for preventing leakage of the cooling medium - H02K 7/116: with gears - H02K 11/33: Drive circuits, e.g. power electronics (H02K11/38 takes precedence) - B60K 11/02: with liquid cooling - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES ## Abstract A device includes: a motor; a gear unit; a power conversion unit; a casing that includes a first chamber and a second chamber separated from each other by a partition wall; and a cooling system that circulates a thermal transfer medium to at least one of the first chamber and the second chamber, wherein the cooling system includes a partition wall cooling route that supplies the thermal transfer medium to the partition wall, and is configured such that a supply amount of the thermal transfer medium to the partition wall cooling route is greater in a state in which vehicle speed of the vehicle is low and output torque of the motor is high, as compared to a state in which the vehicle speed is high and the output torque is low. ## Claims ### Claim 1 A drive device for a vehicle, the drive device comprising: a motor; a gear unit that is mechanically connected to the motor; a power conversion unit that is electrically connected to the motor; a casing that includes a first chamber and a second chamber separated from each other by a partition wall, at least one of the motor and the gear unit being housed in the first chamber, and the power conversion unit being housed in the second chamber; and a cooling system that circulates a thermal transfer medium to at least one of the first chamber and the second chamber, wherein the cooling system includes a partition wall cooling route that supplies the thermal transfer medium to the partition wall, and is configured such that a supply amount of the thermal transfer medium to the partition wall cooling route is greater in a state in which vehicle speed of the vehicle is low and output torque of the motor is high, as compared to a state in which the vehicle speed is high and the output torque is low, and the partition wall cooling route includes a part for jetting the thermal transfer medium to the partition wall. ### Claim 2 (depends on 1) The drive device according to claim 1, wherein, when a vehicle speed index correlated with the vehicle speed is lower than a first threshold value, the greater a torque index correlated with the output torque is, the more the cooling system configured to increase the supply amount of the thermal transfer medium to the partition wall cooling route, stepwise or continuously. ### Claim 3 (depends on 2) The drive device according to claim 2, wherein the cooling system is configured to: adjust the supply amount of the thermal transfer medium to the partition wall cooling route to a first supply amount when the vehicle speed index is lower than the first threshold value and also the torque index is lower than a second threshold value; and adjust the supply amount of the thermal transfer medium to the partition wall cooling route to a second supply amount when the vehicle speed index is lower than the first threshold value and also the torque index is higher than the second threshold value, the second supply amount being greater than the first supply amount. ### Claim 4 A drive device for a vehicle, the drive device comprising: a motor; a gear unit that is mechanically connected to the motor; a power conversion unit that is electrically connected to the motor; a casing that includes a first chamber and a second chamber separated from each other by a partition wall, at least one of the motor and the gear unit being housed in the first chamber, and the power conversion unit being housed in the second chamber; and a cooling system that circulates a thermal transfer medium to at least one of the first chamber and the second chamber, wherein the cooling system includes a partition wall cooling route that supplies the thermal transfer medium to the partition wall, and is configured such that a supply amount of the thermal transfer medium to the partition wall cooling route is greater in a state in which vehicle speed of the vehicle is low and output torque of the motor is high, as compared to a state in which the vehicle speed is high and the output torque is low wherein, when a torque index correlated with the output torque is higher than a second threshold value, the greater a vehicle speed index correlated with the vehicle speed is, the more the cooling system is configured to reduce the supply amount of the thermal transfer medium to the partition wall cooling route, stepwise or continuously, and wherein the cooling system is configured to: adjust the supply amount of the thermal transfer medium to the partition wall cooling route to a second supply amount when the torque index is higher than the second threshold value and also the vehicle speed index is lower than a first threshold value, and adjust the supply amount of the thermal transfer medium to the partition wall cooling route to a third supply amount when the torque index is higher than the second threshold value and also the vehicle speed index is higher than the first threshold value, the third supply amount being smaller than the second supply amount. ### Claim 5 A drive device for a vehicle, the drive device comprising: a motor; a gear unit that is mechanically connected to the motor; a power conversion unit that is electrically connected to the motor; a casing that includes a first chamber and a second chamber separated from each other by a partition wall, at least one of the motor and the gear unit being housed in the first chamber, and the power conversion unit being housed in the second chamber; and a cooling system that circulates a thermal transfer medium to at least one of the first chamber and the second chamber, wherein the cooling system includes a partition wall cooling route that supplies the thermal transfer medium to the partition wall, and is configured such that a supply amount of the thermal transfer medium to the partition wall cooling route is greater in a state in which vehicle speed of the vehicle is low and output torque of the motor is high, as compared to a state in which the vehicle speed is high and the output torque is low, wherein at least the motor is housed in the first chamber, and wherein the cooling system further includes a motor cooling route that supplies the thermal transfer medium to the motor, and is configured to switch, between at least two levels, a ratio of the supply amount of the thermal transfer medium supplied to the partition wall cooling route as to a supply amount of the thermal transfer medium supplied to the motor cooling route, in accordance with a combination of a vehicle speed index correlated with the vehicle speed and a torque index correlated with the output torque. ### Claim 6 (depends on 5) The drive device according to claim 5, wherein, when the torque index is higher than a second threshold value, the greater the vehicle speed index is, the more the cooling system is configured to reduce the ratio, stepwise or continuously. ### Claim 7 (depends on 6) The drive device according to claim 6, wherein the cooling system is configured to: adjust the ratio to a first ratio when the torque index is higher than the second threshold value and also the vehicle speed index is lower than a first threshold value, and adjust the ratio to a second ratio that is smaller than the first ratio when the torque index is higher than the second threshold value and also the vehicle speed index is higher than the first threshold value. ### Claim 8 (depends on 5) The drive device according to claim 5, wherein: the thermal transfer medium is a liquid; and the cooling system further includes a pump that supplies the thermal transfer medium to the partition wall cooling route and the motor cooling route, and a flow rate adjustment unit configured to adjust the ratio of the supply amount of the thermal transfer medium supplied to the partition wall cooling route as to the supply amount of the thermal transfer medium supplied to the motor cooling route. ### Claim 9 (depends on 1) The drive device according to claim 1, wherein: the thermal transfer medium is oil; the first chamber further includes a gear compartment that houses the gear unit; and the oil is stored in the first chamber. ### Claim 10 (depends on 9) The drive device according to claim 9, wherein: the casing further includes a reservoir, for storing the oil, at a lower portion of the gear compartment; a portion of the gear unit is immersed in the oil stored in the reservoir; the cooling system further includes a pump that delivers the oil stored in the reservoir to the partition wall cooling route; and the cooling system is configured to switch a delivery amount from the pump between at least two levels in accordance with a combination of a vehicle speed index correlated with the vehicle speed and a torque index correlated with the output torque. ### Claim 11 (depends on 10) The drive device according to claim 10, wherein, the greater the vehicle speed index is, the more the cooling system is configured to reduce the delivery amount of the oil that is delivered to the partition wall cooling route, stepwise or continuously. ### Claim 12 (depends on 11) The drive device according to claim 11, wherein: the first chamber further includes a motor compartment that houses the motor; the cooling system further includes a motor cooling route that supplies the oil to the motor; the pump delivers the oil stored in the reservoir to the partition wall cooling route and the motor cooling route; and the cooling system is configured to switch a ratio of a supply amount of the oil supplied to the partition wall cooling route as to a supply amount of the oil supplied to the motor cooling route between at least two levels in accordance with a combination of the vehicle speed index and the torque index. ### Claim 13 (depends on 12) The drive device according to claim 12, wherein, when the torque index is higher than a second threshold value, the greater the vehicle speed index is, the more the cooling system is configured to reduce the ratio stepwise or continuously. ### Claim 14 (depends on 13) The drive device according to claim 13, wherein the cooling system is configured to: adjust the ratio to a first ratio when the vehicle speed index is lower than a first threshold value and also the torque index is higher than the second threshold value, and adjust the ratio to a second ratio that is smaller than the first ratio when the vehicle speed index is higher than the first threshold value and also the torque index is higher than the second threshold value. ### Claim 15 (depends on 14) The drive device according to claim 14, wherein the cooling system further includes a flow rate adjustment unit configured to adjust a ratio of the supply amount of the thermal transfer medium supplied to the partition wall cooling route as to a supply amount of the thermal transfer medium supplied to the motor cooling route. ### Claim 16 (depends on 1) The drive device according to claim 1, wherein the partition wall cooling route includes a flow route disposed within the partition wall.