Methods and systems for controlling a pneumatic starter air valve of a gas turbine engine are described herein. The starter air valve is controlled in a first mode of operation by actuating a first solenoid of the starter air valve with a steady-state input signal. Passage of the steady-state input signal to a second solenoid of the starter air valve is allowed, to actuate the second solenoid and enable pressure regulation of the starter air valve. The starter air valve is controlled in a second mode of operation by actuating the first solenoid with a pulse-width modulation input signal. Passage of the pulse-width modulation input signal to the second solenoid is prevented, to disable the pressure regulation in the second mode of operation.

Methods and systems for controlling a pneumatic starter air valve of a gas turbine engine are described herein. The starter air valve is controlled in a first mode of operation by actuating a first solenoid of the starter air valve with a steady-state input signal. Passage of the steady-state input signal to a second solenoid of the starter air valve is allowed, to actuate the second solenoid and enable pressure regulation of the starter air valve. The starter air valve is controlled in a second mode of operation by actuating the first solenoid with a pulse-width modulation input signal. Passage of the pulse-width modulation input signal to the second solenoid is prevented, to disable the pressure regulation in the second mode of operation.

Over-acceleration protection mechanism for ICE or turbine speed regulator with a bushing driven by the gears. The bushing, the component, the washer, the thread, are joined together. The component screws to the thread through the thread. The weights are fitted to the component through the pins and the safety clips, including the valve which is secured by the nut. The lid is screwed to the bushing by means of the screws, while the counterweights come out of the openings of the lid. The thrust bearing and the pressure spring are mounted on the component, adjusted by the screw. The device operates through the centrifugal force which forces the counterweights to rotate in its direction of rotation and to displace the valve by compressing the spring. Then the holes of the fittings communicate with each other, allowing the oil to pass through the joints and the tube and actuate the system.

A linear motion mechanism, including a drive portion, a screw shaft which is rotationally driven about an axis by the drive portion and in which a first spiral screw groove is formed on an outer peripheral surface, a nut in which a second spiral screw groove facing the first screw groove is formed on an inner peripheral surface and which moves forward or backward relative to the screw shaft in an axial direction, in which an axis of the screw shaft extends, according to a rotation of the screw shaft, a plurality of load balls which are disposed in a transfer path formed by the first screw groove and the second screw groove and advance while rolling on the transfer path, a plurality of retainer frames which are disposed between the plurality of load balls and advances on the transfer path along with the load balls.

Provided is a steam turbine overspeed protection system, includes a drive gear arranged to match a rotation speed of a rotor of a steam turbine; a rotating shaft parallel to an axis of the drive gear and capable of rotating at a critical rotation speed; a protective gear arranged on the rotating shaft and forming a lead screw nut mechanism with the rotating shaft, and arranged to be capable of engaging with the drive gear when the rotation speed of the drive gear exceeds the critical rotation speed; and an operating rod connected to the protective gear; wherein, when the drive gear engages with the protective gear, the protective gear can move in the axial direction of the rotating shaft and thereby drive the operating rod to move and produce an action that activates a protection device for preventing steam turbine overspeed.

A turbine pump assembly has a turbine, a centrifugal pump, and a passive electrical speed control system. The turbine has a peak efficiency at a first speed that is lower than a second speed at which the centrifugal pump is operating at a peak power requirement. A rocket thrust vector control system is also disclosed.

A system may comprise a sensor configured to measure a characteristic of an engine component. A valve assembly may have an airflow outlet in fluid communication with the engine component. The valve assembly may include a first valve. A first valve control device may be coupled to the first valve and configured to control the first valve based on a measurement by the sensor. A second valve may be in fluidic series with the first valve. A second valve control device may be coupled to the second valve and configured to control the second valve based on the measurement by the sensor.