Abstract: A system of a work vehicle includes an engine, a transmission that includes a hydrostatic unit, and a clutch coupled to the transmission. The system also includes a controller communicatively coupled to the engine, the transmission, and the clutch. The controller, in operation, receives a command to disengage the clutch. The controller, in operation, determines an engine speed of the engine. The controller, in operation, also determines a temperature of hydraulic fluid in the clutch. The controller, in operation, further determines a magnitude and time to limit acceleration of the work vehicle based on the engine speed and the temperature. The controller, in operation, also commands the clutch to disengage. The controller, in operation, further limits the acceleration of the work vehicle using the hydrostatic unit based on the magnitude for the time determined.

Abstract: A system for operating a work vehicle may include an engine and a transmission coupled to the engine. The transmission may include a planetary gear unit configured to be selectively coupled to the engine by engaging one of two directional clutches of the transmission. The transmission may also include a hydrostatic drive unit having an input configured to be rotationally coupled to the engine and an output configured to be rotationally coupled to the planetary gear unit. Moreover, the transmission may include a bypass shaft assembly having a bypass shaft configured to be selectively coupled between the output of the hydrostatic drive unit and a given range clutch of the transmission via a bypass clutch. In addition, the system may include a controller configured to operate the transmission in a hydrostatic bypass mode by disengaging the directional clutches and by engaging the bypass clutch and the given range clutch.

Abstract: A system of a work vehicle includes an engine, a transmission that includes a hydrostatic unit, and a clutch coupled to the transmission. The system also includes a controller communicatively coupled to the engine, the transmission, and the clutch. The controller, in operation, receives a command to disengage the clutch. The controller, in operation, determines an engine speed of the engine. The controller, in operation, also determines a temperature of hydraulic fluid in the clutch. The controller, in operation, further determines a magnitude and time to limit acceleration of the work vehicle based on the engine speed and the temperature. The controller, in operation, also commands the clutch to disengage. The controller, in operation, further limits the acceleration of the work vehicle using the hydrostatic unit based on the magnitude for the time determined.

Abstract: A swash plate angle for a hydrostatic power unit of a continuously variable hydromechanical transmission is determined using a feedforward compensation term, to reduce reliance on closed loop control. The feedforward term is based on knowledge of the hydrostatic power unit determined as a function of knowledge of certain parameters, including, but not limited to, hydrostatic power unit pressure, swash plate angle, desired hydrostatic power unit ratio, and pump speed.

Abstract: A swash plate angle for a hydrostatic power unit of a continuously variable hydromechanical transmission is determined using a feedforward compensation term, to reduce reliance on closed loop control. The feedforward term is based on knowledge of the hydrostatic power unit determined as a function of knowledge of certain parameters, including, but not limited to, hydrostatic power unit pressure, swash plate angle, desired hydrostatic power unit ratio, and pump speed.

Abstract: An active suspension system for a rigid beam tractor axle in which the axle is connected to the chassis by two orthogonally oriented pivot points and axle movement is controlled by double-acting suspension actuators managed by a control system to improve the ride and handling characteristics of the tractor.

Abstract: An active suspension system for a rigid beam tractor axle in which the axle is connected to the chassis by two orthogonally oriented pivot points and axle movement is controlled by double-acting suspension actuators managed by a control system to improve the ride and handling characterstics of the tractor.

Abstract: A skid steer vehicle has a chassis with four drive wheels suspended from the chassis that are damped by four damping cylinders. An electronic controller varies the damping of the cylinders in an automatic mode, based on certain operational parameters of the vehicle, and in a manual mode in response to operator selection of a desired degree of suspension damping.

Abstract: A skid steer vehicle has two drive motors that are connected by belts to spring-mounted front and rear wheels.

Abstract: A skid steer vehicle is supported on four gearboxes that function both as control arms and as speed reduction gearboxes. Each side of the vehicle's chassis has two gearboxes to which it is coupled. A hydraulic motor is fixed to each side of the chassis to drive the gearboxes on that side. The motors are arranged such that their drive shafts extend longitudinally along the chassis, with a front shaft engaging the front gearbox and a rear shaft engaging the rear gearbox. The gearboxes include three speed-reducing right angle gear sets coupling an axle extending from the gearbox to the motor driving that gearbox.

Abstract: A skid steer vehicle has a suspension that includes two bogies pivotally connected to the sides of the vehicle and extending fore-and-aft along each side of the vehicle. The bogies are pivotally connected to the vehicle in the middle and have a wheel mounted at each end. A hydraulic motor is coupled to each of the bogies and drives the two wheels on each bogie.

Abstract: A control system for a skid steer vehicle reads a load height sensor, a load amount sensor, and a vehicle speed sensor to derate the otherwise commanded acceleration, deceleration and turning rate on the vehicle when the vehicle has too great a load, too high a load, or the vehicle is going too fast.

Abstract: A skid steer vehicle has a chassis with an engine mounted thereon and is supported by four suspensions located at the left front, the left rear, the right front and the right rear of the vehicle. The suspensions include control arms that extend laterally away from the vehicle that are connected to struts for steering the vehicle. Wheels are connected to the struts to support the vehicle. Two wheels on the left side of the vehicle are driven by a first hydraulic motor and two wheels on the right side of the vehicle are driven by a second hydraulic motor. The wheels can be steered such that the front wheels point to the left and the rear wheels point to the right, and such that the front wheels point to the right and the rear wheels point to the left.

Abstract: A skid steer vehicle with steerable suspension has hydraulic motors coupled to four steerable wheels. The wheels are turned by hydraulic actuators and the vehicle is steered either by turning the wheels or by driving the wheels on opposite sides of the vehicle in opposite directions and skid steering the vehicle.

Abstract: A skid steer vehicle is supported on four gearboxes that function both as control arms and as speed reduction gearboxes. Each side of the vehicle's chassis has two gearboxes to which it is coupled. A hydraulic motor is fixed to each side of the chassis to drive the gearboxes on that side. The motors are arranged such that their drive shafts extend longitudinally along the chassis, with a front shaft engaging the front gearbox and a rear shaft engaging the rear gearbox. The gearboxes include three speed-reducing right angle gear sets coupling an axle extending from the gearbox to the motor driving that gearbox.

Abstract: A skid steer vehicle has sprung suspensions, variable displacement pumps and motors connected to those pumps that drive the wheels on the vehicle as well as an electronic controller that receives signals that indicate fore-and-aft acceleration of the skid steer vehicle. Based on these signals, the controller determines whether the forward acceleration exceeds a predetermined value and locks up the rear suspensions if that value is exceeded. It also determines whether the forward deceleration exceeds a predetermined value and locks up the front suspensions if that value is exceeded. The signals can be provided by an accelerometer, a satellite receiver, wheel/motor speed sensors, sensors in the pumps that signal the specific displacement of the pumps such as their swash plate positions, or memory locations that contain previously calculated specific displacement commands that are used to drive the pumps to a particular specific displacement.

Abstract: A skid steer vehicle has sprung suspensions that can be locked to prevent vertical movement with respect to the chassis of the vehicle. The operator controls include a switch that the operator can manipulate to lock the suspensions on command. The switch is mounted on a joystick that is used to perform other vehicle functions such as moving the vehicle, raising loader arms, or tilting the bucket or other implement attached to the loader arms. The switch is located on the joystick such that the operator can manipulate the switch without having to remove his hands from the joystick.

Abstract: A skid steer loader has a chassis with spring-loaded suspensions that are pivotally coupled to the chassis closer to the center of gravity than the wheels. The suspensions include fore-and-aft extending swing arms that pivot about a lateral axis with respect to the chassis. A torsion spring such as a torsion bar is coupled to the control arm to provide torsional support for the suspension. The torsion spring is anchored to the chassis nearer the center of gravity than the point where the swing arm is coupled to the chassis.

Abstract: A skid steer loader has a chassis having front and rear ends, and an engine mounted to the rear end of the chassis. There are four suspensions pivotally coupled to the chassis to pivot with respect to the chassis. Two of the suspensions are extended laterally outward from the left side of the chassis and the other two suspensions are extended laterally outward from the right side of the chassis. Wheels on the suspensions are driven by drive shafts extending from a longitudinal splitter box that, in turn, are coupled to two hydraulic motors.

Abstract: A skid steer vehicle includes a chassis mounted on four sprung suspensions that are controlled by an electronic controller. The controller monitors the speed of the vehicle and locks the suspensions when the vehicle falls below a predetermined speed.