# US 12,110,961 B2 · Transmission system for an electric vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,110,961 B2 - Document ID: US12110961B2 - Status: Granted - Kind: B2 - Application number: 17/814,379 - Filed: 2022-07-22 - Published: 2022-11-10 - Granted: 2024-10-08 - Earliest claimed: 2020-03-18 - Assignees: Karma Automotive LLC - Applicants: Karma Automotive LLC - Inventors: Shashank Vijay - Web page: https://patentgrep.com/patent/US12110961B2 ## CPC - F16H 57/0443: {for supply of lubricant during tilt or high acceleration, e.g. problems related to the tilt or extreme acceleration of the transmission casing and the supply of lubricant under these conditions} - F16H 57/02: Gearboxes; Mounting gearing therein - F16H 57/0409: {characterised by increasing efficiency, e.g. by reducing splash losses} - F16H 57/0435: {Pressure control for supplying lubricant; Circuits or valves therefor} - F16H 57/0436: {Pumps} - F16H 57/0447: {Control of lubricant levels, e.g. lubricant level control dependent on temperature} - F16H 57/045: {Lubricant storage reservoirs, e.g. reservoirs in addition to a gear sump for collecting lubricant in the upper part of a gear case} - F16H 57/0457: {Splash lubrication} - F16H 2057/02043: {for vehicle transmissions} - F16H: GEARING ## Abstract A transmission system for an electric vehicle. The system includes a gearbox containing gears and a lubricating fluid. A pump is provided for supplying and removing lubricating fluid from the gear box. The operation of the pump is controlled by a controller. A reservoir is provided for storing lubricating fluid. The controller is configured to control the pump so that a portion of the lubricating fluid is removed from the gear box when the vehicle is involved in a high acceleration event. ## Claims ### Claim 1 A method comprising: receiving sensor information from a motor speed sensor of a vehicle, the sensor information representing a motor speed of an electric motor of the vehicle, the vehicle including a transmission that comprises: a gearbox containing a volume of lubricating fluid; and a pump fluidly connected to the gearbox; determining a current acceleration of the vehicle based on the received sensor information representing the motor speed of the electric motor of the vehicle; determining that the current acceleration of the vehicle is greater than a first predetermined acceleration level; and in response to determining that the current acceleration of the vehicle is greater than the first predetermined acceleration level, starting operation of the pump to remove a portion of the volume of lubricating fluid from the gearbox, wherein the pump continuously operates while the current acceleration of the vehicle is greater than the first predetermined acceleration level. ### Claim 2 (depends on 1) The method of claim 1, wherein: the transmission further comprises a reservoir fluidly connected to the pump and the gearbox; and starting operation of the pump to remove the portion of the volume of lubricating fluid from the gearbox comprises operating the pump to move the portion of the volume of lubricating fluid from the gearbox to the reservoir. ### Claim 3 (depends on 1) The method of claim 1, where the operations further comprise: determining that the current acceleration of the vehicle is less than a second predetermined acceleration level, the second predetermined acceleration level less than the first predetermined acceleration level; and in response to determining that the current acceleration of the vehicle is less than the second predetermined acceleration level, operating the pump to return the portion of the volume of lubricating fluid to the gearbox. ### Claim 4 (depends on 3) The method of claim 3, wherein the second predetermined acceleration level is equal to a g-force of at least 0.5. ### Claim 5 (depends on 3) The method of claim 3, wherein the second predetermined acceleration level is less than or equal to a g-force of 1.0. ### Claim 6 (depends on 1) The method of claim 1, wherein the first predetermined acceleration level is equal to a g-force of at least 1.0. ### Claim 7 (depends on 1) The method of claim 1, wherein the pump comprises a screw-type pump. ### Claim 8 (depends on 1) The method of claim 1, wherein the gearbox comprises a single speed gearbox. ### Claim 9 (depends on 1) The method of claim 1, wherein the gearbox comprises a multi-speed gearbox. ### Claim 10 A vehicle comprising: a transmission comprising: a gearbox containing a volume of lubricating fluid; and a pump fluidly connected to the gearbox; an electric motor; a motor speed sensor; and a controller in communication with the motor speed sensor and the transmission, the controller performing operations comprising: receiving sensor information from the motor speed sensor, the sensor information indicating a motor speed of the electric motor; determining a current acceleration of the vehicle based on the received sensor information representing the motor speed of the electric motor; determining that the current acceleration of the vehicle is greater than a first predetermined acceleration level; and in response to determining that the current acceleration of the vehicle is greater than the first predetermined acceleration level, starting operation of the pump to remove a portion of the volume of lubricating fluid from the gearbox, wherein the pump continuously operates while the current acceleration of the vehicle is greater than the first predetermined acceleration level. ### Claim 11 (depends on 10) The vehicle of claim 10, wherein: the transmission further comprises a reservoir fluidly connected to the pump and the gearbox; and starting operation of the pump to remove the portion of the volume of lubricating fluid from the gearbox comprises operating the pump to move the portion of the volume of lubricating fluid from the gearbox to the reservoir. ### Claim 12 (depends on 10) The vehicle of claim 10, where the operations further comprise: determining that the current acceleration of the vehicle is less than a second predetermined acceleration level, the second predetermined acceleration level less than the first predetermined acceleration level; and in response to determining that the current acceleration of the vehicle is less than the second predetermined acceleration level, operating the pump to return the portion of the volume of lubricating fluid to the gearbox. ### Claim 13 (depends on 12) The vehicle of claim 12, wherein the second predetermined acceleration level is equal to a g-force of at least 0.5. ### Claim 14 (depends on 12) The vehicle of claim 12, wherein the second predetermined acceleration level is less than or equal to a g-force of 1.0. ### Claim 15 (depends on 10) The vehicle of claim 10, wherein the first predetermined acceleration level is equal to a g-force of at least 1.0. ### Claim 16 (depends on 10) The vehicle of claim 10, wherein the pump comprises a screw-type pump. ### Claim 17 (depends on 10) The vehicle of claim 10, wherein the gearbox comprises a single speed gearbox. ### Claim 18 (depends on 10) The vehicle of claim 10, wherein the gearbox comprises a multi-speed gearbox.