# US 10,308,255 B2 · Slip control method and arrangement for a driveline including a continuously variable transmission > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,308,255 B2 - Document ID: US10308255B2 - Status: Granted - Kind: B2 - Application number: 15/112,175 - Filed: 2015-01-12 - Published: 2016-11-17 - Granted: 2019-06-04 - Earliest claimed: 2014-01-16 - Assignees: Transmission Cvtcorp Inc. - Applicants: Transmission Cvtcorp Inc. - Inventors: Jean-François Dionne; Jean-Robert Desmeules; Jonathan Guérin; Daniel Girard - Web page: https://patentgrep.com/patent/US10308255B2 ## CPC - B60W 30/1884: {Avoiding stall or overspeed of the engine} - B60W 10/02: including control of driveline clutches - B60W 10/101: Infinitely variable gearings - F16D 48/06: Control by electric or electronic means, e.g. of fluid pressure - F16H 61/66: specially adapted for continuously variable gearings (control of exclusively fluid gearing F16H61/38) - B60W 2510/0241: Clutch slip, i.e. difference between input and output speeds - B60W 2510/0657: Engine torque - B60W 2710/025: Clutch slip, i.e. difference between input and output speeds - B60W 2710/1005: Transmission ratio engaged - F16D 2500/1088: CVT - F16D 2500/30406: Clutch slip - F16D 2500/3065: Torque of the engine - F16D 2500/3067: Speed of the engine - F16D 2500/5048: Stall prevention - F16D 2500/70426: Clutch slip - F16D 2500/7044: Output shaft torque - F16D 2500/70488: Selection of the gear ratio - F16H 59/56: dependent on signals from the main clutch - F16H 63/46: Signals to a clutch outside the gearbox - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - F16H: GEARING ## Abstract A slip control method and arrangement for a driveline including a continuously variable transmission is described herein. The driveline includes a clutch that is so controlled as to slip when a torque higher than the usable torque attempts to pass through. Accordingly, the clutch prevents the prime mover from stalling. ## Claims ### Claim 1 A method to control the slippage of a driveline including a prime mover having an output shaft, a continuously variable transmission having an input connected to the output shaft of the prime mover and an output, a clutch having an input connected to the output of the continuously variable transmission and an output; the clutch having a controllable slippage level between its input and output, and a load connected to the output of the clutch, the slippage control method including: determining the usable torque of the prime mover; and controlling the slippage level of the clutch so as to allow the usable torque to pass therethrough and to cause the clutch to slip should a torque between the input and output of the clutch be greater than the usable torque. ### Claim 2 (depends on 1) The slippage control method of claim 1, wherein the usable torque determining includes determining an available torque of the prime mover according to an instantaneous speed of an output shaft of the prime mover and calculating a usable torque at the instantaneous speed of the prime mover. ### Claim 3 (depends on 1) The slippage control method of claim 1 further comprising: detecting a slippage level of the clutch; setting the CVT ratio as a function of the slippage level of the clutch so as to increase the usable torque. ### Claim 4 (depends on 1) The slippage control method of claim 1 further including integrating the driveline to an off-highway vehicle. ### Claim 5 A driveline including: a prime mover having an output shaft; a prime mover speed sensor measuring the rotational speed of the output shaft; a CVT having an input associated with the output shaft of the prime mover and an output; a clutch having an input associated with the output of the CVT and an output; a clutch slip controller controlling the level of torque allowed to pass through the clutch before slippage occurs therein; and a main controller associated with the prime mover speed sensor and with the clutch slip controller; the main controller being so configured as to determine a usable torque of the prime mover and to set the clutch slip controller so that the clutch slips when a torque higher than the usable torque attempts to pass through the clutch. ### Claim 6 (depends on 5) The driveline recited in claim 5, wherein the usable torque is determined as a function of the rotational speed of the output shaft of the prime mover. ### Claim 7 (depends on 5) The driveline recited in claim 5, further comprising means to detect slippage in the clutch and a ratio controller setting the output/input ratio of the CVT; wherein the ratio controller decreases the CVT ratio when slippage is detected. ### Claim 8 (depends on 7) The driveline recited in claim 7, wherein the means to detect slippage includes an input speed sensor measuring the speed of the clutch input and an output speed sensor measuring the speed of the clutch output. ### Claim 9 (depends on 5) The driveline recited in claim 5, further comprising a user control to manually disengage the clutch. ### Claim 10 (depends on 7) The driveline recited in claim 7, wherein the ratio controller and the clutch slip controller are integrated with the main controller. ### Claim 11 (depends on 5) The driveline recited in claim 5, where the driveline is integrated in an off-highway vehicle.