# US 10,870,423 B1 · Transfer case control to relieve front driveline residual torque > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,870,423 B1 - Document ID: US10870423B1 - Status: Granted - Kind: B1 - Application number: 16/537,677 - Filed: 2019-08-12 - Granted: 2020-12-22 - Earliest claimed: 2019-08-12 - Assignees: Fca US LLC - Applicants: Jeffrey M Orzechowski; Kenneth Pachucki; Urmit Patel; Robert R Roco; Gregory A Sbroglia; Donald F Schmanski; Swapneel H Gharpure - Inventors: Jeffrey M Orzechowski; Kenneth Pachucki; Urmit Patel; Robert R Roco; Gregory A Sbroglia; Donald F Schmanski; Swapneel H Gharpure - Web page: https://patentgrep.com/patent/US10870423B1 ## CPC - B60K 17/35: including arrangements for suppressing or influencing the power transfer, e.g. viscous clutches - B60W 10/119: including control of all-wheel-driveline means, e.g. transfer gears or clutches for dividing torque between front and rear axle (B60W10/14 takes precedence) - B60K 23/0808: {for varying torque distribution between driven axles, e.g. by transfer clutch} - B60T 8/173: Eliminating or reducing the effect of unwanted signals, e.g. due to vibrations or electrical noise - F16D 48/06: Control by electric or electronic means, e.g. of fluid pressure - B60K 2023/0825: {for adding torque to the front wheels} - B60W 30/18118: {Hill holding} - F16D 2500/1026: Hydraulic - F16D 2500/104: Clutch - F16D 2500/30415: Speed of the input shaft - F16D 2500/30426: Speed of the output shaft - F16D 2500/3118: Slip of vehicle wheels - F16D 2500/50287: Torque control - F16D 2500/5075: Prevention or regulation of vehicle's wheel slip - 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 - 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 - B60T: VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL (electrodynamic brake systems for vehicle, in general B60L; brakes per se, i.e. devices where braking effect occurs, including ultimate brake actuators, F16D); ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES ## Abstract A vehicle includes an engine, a pair of front axle shafts, and a transfer case having a clutch assembly configured to selectively move between a closed position to enable the engine to drive the front axle shafts, and an open position to disable the engine from driving the front axle shafts. A control system is configured to momentarily open the clutch assembly when the vehicle is coming to a stop or is stopped in order to relieve residual torque build-up in the front axle shafts to thereby reduce idle vibration transmission between the engine and a body of the vehicle. ## Claims ### Claim 1 A vehicle having a selective four wheel drive mode of operation, the vehicle comprising: an engine; a pair of front axle shafts; a transfer case having a clutch assembly configured to selectively move between a closed position to enable the engine to drive the front axle shafts, and an open position to disable the engine from driving the front axle shafts; and a control system configured to momentarily open the clutch assembly when the vehicle is coming to a stop or is stopped in order to relieve residual torque build-up in the front axle shafts to thereby reduce idle vibration transmission between the engine and a body of the vehicle. ### Claim 2 (depends on 1) The vehicle of claim 1, wherein the control system momentarily opens the clutch assembly to relieve residual torque build-up only when the vehicle is operating in a four-wheel drive mode or an all-wheel drive mode where the clutch assembly is in the closed position such that the engine drives the front axle shafts. ### Claim 3 (depends on 1) The vehicle of claim 1, wherein the momentary opening of the clutch assembly comprises opening the clutch assembly for less than or equal to 5.0 seconds. ### Claim 4 (depends on 3) The vehicle of claim 3, wherein the momentary opening of the clutch assembly comprises opening the clutch assembly for less than or equal to 1.0 second. ### Claim 5 (depends on 1) The vehicle of claim 1, wherein control system momentarily opens the clutch assembly only when the vehicle is stopped. ### Claim 6 (depends on 1) The vehicle of claim 1, wherein control system momentarily opens the clutch assembly only when the vehicle is coming to a stop. ### Claim 7 (depends on 1) The vehicle of claim 1, wherein the control system includes a controller in signal communication with a drive mode sensor, and the control system momentarily opens the clutch assembly only if the controller receives a signal from the drive mode sensor indicating the vehicle is in an on-road drive mode. ### Claim 8 (depends on 1) The vehicle of claim 1, wherein the control system includes a controller in signal communication with a vehicle speed sensor, and the control system momentarily opens the clutch assembly only if the controller receives a signal from the vehicle speed sensor indicating a speed of the vehicle is below a first predetermined threshold and/or the accelerator pedal position is below a second predetermined threshold position. ### Claim 9 (depends on 1) The vehicle of claim 1, wherein the control system includes a controller in signal communication with a brake pressure sensor, and the control system momentarily opens the clutch assembly only if the controller receives a signal from the brake pressure sensor indicating a brake torque driver request is above a first predetermined threshold and/or an actual brake torque is above a second predetermined threshold. ### Claim 10 (depends on 1) The vehicle of claim 1, wherein the control system includes a controller in signal communication with a gear selection sensor, and the control system momentarily opens the clutch assembly only if the controller receives a signal from the gear selection sensor indicating a vehicle transmission is in Drive. ### Claim 11 (depends on 1) The vehicle of claim 1, wherein the control system includes a controller in signal communication with an incline sensor, and the control system momentarily opens the clutch assembly only if the controller receives a signal from the incline sensor indicating a slope of a surface the vehicle is on is less than a predetermined threshold. ### Claim 12 (depends on 1) The vehicle of claim 1, wherein the control system starts a timer when the clutch assembly is momentarily opened and only closes the clutch assembly when the time since the momentary opening is greater than a predetermined threshold. ### Claim 13 A method of controlling a vehicle having an engine, a pair of front axle shafts, and a transfer case having a clutch assembly selectively movable between a closed position where the engine is enabled to drive the front axle shafts, and an open position where the engine is disabled from driving the front axle shafts, the method comprising: operating the transfer case in a four-wheel drive mode or an all-wheel drive mode where the clutch assembly is in the closed position and the engine drives the front axle shafts; and upon the clutch assembly being in the closed position and the vehicle is coming to a stop or is stopped, momentarily opening the clutch assembly in order to relieve residual torque build-up in the front axle shafts to thereby reduce idle vibration transmission between the engine and a body of the vehicle. ### Claim 14 (depends on 13) The method of claim 13, further comprising determining the vehicle is in an on-road drive mode, wherein said momentary opening of the clutch assembly is not performed if the vehicle is not in the on-road drive mode. ### Claim 15 (depends on 13) The method of claim 13, further comprising determining if a vehicle speed is less than a first predetermined threshold and/or if an accelerator pedal position is less than a second predetermined threshold, wherein said momentary opening of the clutch assembly is not performed if the vehicle speed is greater than the first predetermined threshold and/or if the accelerator pedal position is greater than the second predetermined threshold. ### Claim 16 (depends on 13) The method of claim 13, further comprising determining if a brake torque driver request is greater than a first predetermined threshold and/or if an actual brake torque is greater than a second predetermined threshold, wherein said momentary opening of the clutch assembly is not performed if the brake torque driver request is less than the first predetermined threshold and/or if the actual brake torque is less than the second predetermined threshold. ### Claim 17 (depends on 13) The method of claim 13, further comprising determining if a transmission of the vehicle is in Drive, wherein said momentary opening of the clutch assembly is not performed if the vehicle transmission is not in Drive. ### Claim 18 (depends on 13) The method of claim 13, further comprising determining if a slope of a surface the vehicle is on is less than a predetermined threshold, wherein said momentary opening of the clutch assembly is not performed if the slope is greater than the predetermined threshold. ### Claim 19 (depends on 13) The method of claim 13, further comprising: determining if the vehicle is in an on-road drive mode; determining if a vehicle speed is less than a first predetermined threshold and if an accelerator pedal position is less than a second predetermined threshold; determining if a brake torque driver request is greater than a third predetermined threshold and if an actual brake torque is greater than a fourth predetermined threshold; determining if a transmission of the vehicle is in Drive; and determining if a slope of a surface the vehicle is on is less than a fifth predetermined threshold, wherein said momentary opening of the clutch assembly is performed if the vehicle is in the on-road drive mode, the vehicle speed is less than the first predetermined threshold, the accelerator pedal position is less than the second predetermined threshold, the brake torque driver request is greater than the third predetermined threshold, the actual brake torque is greater than the fourth predetermined threshold, the vehicle transmission is in Drive, and the slope is less than the fifth predetermined threshold.