Abstract: Interruption in supervisory position control signals can cause problems with respect to actuators which upon loss of such control signals for the actuator will generally slew to a fixed idle position. In such circumstances a machine such as a gas turbine engine in which an actuator is associated will not sustain performance even though there is continued local power supply to the actuator. By utilizing a local controller which stores actuator response profiles for certain machine status stages through perturbation or marginal activation of the actuator an appropriate actuator response profile can be chosen and therefore sustaining control signals presented to the actuator to maintain machine operation.

Abstract: A device for the automatic control of a clutch, in particular of vehicles in which the degree of clutch engagement is determined by the position of an accelerator of the vehicle, such as an accelerator pedal or handle. The device includes an actuation member connected to the clutch and two movable elements whose positions are associated with the degree of clutch engagement of the vehicle and the position of the accelerator, respectively. The movable elements include a switch for making or breaking an electric contact in dependence on the positions of the elements relative to one another.

Abstract: A control system for a work vehicle transmission includes a sensor for detecting the output speed of the vehicle engine and an operator-movable command device for placing the transmission in a neutral condition. The transmission includes a plurality of intermeshing gears, and clutches associated with certain of the gears for selectively placing the transmission in various gear ratios for driving the vehicle. The clutches are engaged and disengaged by fluid valving in response to energization of solenoid coils driven by valve driver circuits. The sensor, the command device and the driver circuits are coupled to a control circuit, preferably including a microprocessor, for controlling engagement and disengagement of the transmission clutches. Upon startup, the control circuit disables the driver circuits to place the transmission in a neutral condition despite the position of the command device.

Abstract: The clutch actuation system provides for control of the clutch of a manual transmission in a motor vehicle. By use of hydraulics, a vacuum booster and a gradual pressure relief valve a smooth easy control of the manual transmission is accomplished. The vacuum booster provides an assist to the hydraulic system when the clutch must be disengaged or engaged. The power assist facilitates rapid engagement of the clutch and gears. The gradual pressure relief valve provides for a smooth transition in the hydraulic system to engage and disengage the clutch. The rapid smooth assist is aided by the vacuum system of the motor vehicle. For certain motor vehicles the engine oil system is also used to assist.