Patent classifications
F16H2048/205
System and method for operating vehicle in selected vehicle mode
A system includes a differential, sensors, and a controller. The differential is operable in a first differential mode in which a first shaft and a second shaft are allowed to rotate at different speeds, and a second differential mode in which the differential inhibits relative rotation between the first and second shafts. The sensors are configured to measure vehicle operating conditions. The controller is in communication with the sensors and the differential. The controller, when the vehicle mode is selected, is configured to determine if an intended path of the vehicle is straight, determine if a vehicle speed is less than a predetermined vehicle speed, and operate the differential in the second differential mode for a predetermined time period in response to the controller determining that the intended path of the vehicle is straight and the vehicle speed is less than the predetermined vehicle speed.
TORQUE STEER MITIGATION EMPLOYING A LIMITED SLIP DIFFERENTIAL ON A STEERING AXLE
A method for mitigating torque steer in a vehicle having a steering axle with a limited slip differential and a pair of output members. The limited slip differential includes a pair of differential outputs and a clutch. The method includes: operating the limited slip differential with the clutch in the first condition; determining that the vehicle is in a state in which a torque steer condition is occurring or is likely to occur; and operating the clutch to reduce a torque differential between the differential outputs to mitigate the torque steer condition. A vehicle with a steering axle and a controller that is configured to operate a clutch in the steering axle to attenuate torque steer is also provided.
Differential and electromagnetic differential with main and pilot clutches
A differential can comprise a pilot clutch, a main clutch, a first ball ramp configured to act on the pilot clutch, and a second ball ramp configured to actuate the main clutch when the pilot clutch acts on the second ball ramp. An electromagnetic differential can comprise a carrier, a stator mounted on the carrier, a pilot clutch in the carrier, and a main clutch in the carrier. An electromagnetic differential can comprise a carrier and a first side gear and a second side gear in the carrier. A pilot clutch can be in the carrier surrounding a portion of the first side gear. A main clutch can be in the carrier surrounding a portion of the pilot clutch and surrounding a portion of the first side gear.
DIFFERENTIAL AND ELECTROMAGNETIC DIFFERENTIAL WITH MAIN AND PILOT CLUTCHES
A differential can comprise a pilot clutch, a main clutch, a first ball ramp configured to act on the pilot clutch, and a second ball ramp configured to actuate the main clutch when the pilot clutch acts on the second ball ramp. An electromagnetic differential can comprise a carrier, a stator mounted on the carrier, a pilot clutch in the carrier, and a main clutch in the carrier. An electromagnetic differential can comprise a carrier and a first side gear and a second side gear in the carrier. A pilot clutch can be in the carrier surrounding a portion of the first side gear. A main clutch can be in the carrier surrounding a portion of the pilot clutch and surrounding a portion of the first side gear.
Control of a limited slip differential based on a steering angle of a vehicle
A limited slip differential (LSD) transfers a torque from an engine to left and right wheels of a vehicle. A current angle of a steering device is determined. Rotational speeds of 5 the left and right driven wheels are also determined. A current wheel slip of is calculated as a difference between the rotational speeds of the left and right wheels. Maximum and minimum allowed wheel slips are calculated as a function of the current steering angle. The LSD is controlled so that the current wheel slip stays in a range between the maximum and minimum allowed wheel slips. To this end, the LSD is loaded if the wheel slip falls outside of the range 0 between the maximum and minimum allowed wheel slips.
CONTROL OF A LIMITED SLIP DIFFERENTIAL OPTIMIZED FOR SLIPPERY DRIVING CONDITIONS
A vehicle has an engine, a limited slip differential (LSD) mounted on an axle driven by the engine, and left and right wheels operably connected to the LSD. At least one parameter indicative of a riding condition of the vehicle is determined. A slippery driving condition is detected based on the at least one parameter. The LSD is selectively locked in response to the detection. The slippery driving condition is detected when a torque requested by a user is above a load line of the engine, upon successive wheel slips occurrences, and/or when a wheel slip is detected while a preload is applied to the LSD.
CONTROL OF A LIMITED SLIP DIFFERENTIAL BASED ON A STEERING ANGLE OF A VEHICLE
A limited slip differential (LSD) transfers a torque from an engine to left and right wheels of a vehicle. A current angle of a steering device is determined. Rotational speeds of 5 the left and right driven wheels are also determined. A current wheel slip of is calculated as a difference between the rotational speeds of the left and right wheels. Maximum and minimum allowed wheel slips are calculated as a function of the current steering angle. The LSD is controlled so that the current wheel slip stays in a range between the maximum and minimum allowed wheel slips. To this end, the LSD is loaded if the wheel slip falls outside of the range 0 between the maximum and minimum allowed wheel slips.
CONTROL OF A LIMITED SLIP DIFFERENTIAL BASED ON AN ACCELERATOR CONTROL POSITION
A vehicle has an engine, an accelerator control, a limited slip differential (LSD) mounted on an axle driven by the engine, and left and right wheels operably connected to the LSD. An accelerator control position is sensed. A speed of the vehicle is optionally sensed. In order to prevent wheel spin, a high load is selectively applied to the LSD when the accelerator control position meets or exceeds a predetermined position threshold. Optionally, application of the high load may depend on the speed of the vehicle being less than a predetermined speed threshold, the accelerator control position concurrently meeting or exceeding the predetermined position threshold. In order to enhance directional stability of the vehicle, a stabilization load is optionally applied when the speed of the vehicle meets or exceeds the predetermined speed threshold.
VEHICLE DRIVE SYSTEM
A vehicle drive system configured to achieve a required driving force of braking force without changing an orientation of a vehicle in the event of slippage of a wheel. The vehicle drive system comprises: a torque generating device; a differential mechanism that allows a relative rotation between a right wheel and a left wheel; a differential restricting device that restricts a differential rotation between the right wheel and the left wheel; and a steering mechanism that controls a turning angle of pairs of the wheels. A first controller controls the relative rotation between the right wheel and the left wheel to be smaller than a predetermined value and second controller further controls a turning angle of the wheels controlled by the steering mechanism.
Behavior control device for four-wheel drive vehicle
A behavior control device for a four-wheel drive vehicle that is applied to a vehicle which includes a center differential device that transmits a driving force from a driving device to front and rear wheel rotation shafts, and permits differential of the front and rear wheel rotation shafts; and a braking force distribution ratio of the front and rear wheels being set to a value in which a proportion of front wheels is larger than that in an ideal distribution ratio. The behavior control device includes a differential limiting device that changes the limitation degree of a differential between the wheel rotation shafts, and a control unit that controls the differential limiting device to increase the limitation degree of the differential during the vehicle is braked as a degree of an understeer state of the vehicle is high.