A brake actuator for a brake rigging in a railway brake system includes a brake cylinder; a piston rod disposed on the brake cylinder and connected to a piston assembly in the brake cylinder, the piston rod being configured to be moved by the piston assembly in a reciprocal axial motion and including at least one lateral protrusion extending therefrom; and an extension cylinder disposed on the brake cylinder at least partially surrounding the piston rod, the extension cylinder including at least one cam surface engaged by the at least one lateral protrusion of the piston rod. The extension cylinder is configured to be connected to a hand brake mechanism and to be actuated by the hand brake mechanism to rotate such that the cam surface engages the lateral protrusion of the piston rod to cause the piston rod to move to the extended position.

An apparatus includes a drive mechanism, a first cylinder comprising a first piston coupled to the drive mechanism, and a second cylinder comprising a second piston. The first cylinder includes a first fluid reservoir and a second fluid reservoir, with the first piston disposed between the first fluid reservoir and the second fluid reservoir. The second cylinder includes a third fluid reservoir and a fourth fluid reservoir, with the second piston disposed between the third fluid reservoir and the fourth fluid reservoir. The apparatus further includes a first fluid line coupling the first fluid reservoir to the fourth fluid reservoir, and a second fluid line coupling the second fluid reservoir to the third fluid reservoir. The first piston comprises a threaded portion disposed in a threaded aperture of the first cylinder.

An electronic clutch actuator for actuation of a clutch in a transmission of a vehicle includes a clutch master cylinder having a fluid cavity therein and adapted to be in fluid communication with a clutch slave cylinder coupled to the clutch of the transmission and a clutch footpedal of the vehicle, the clutch master cylinder having a first port fluidly communicating with the fluid cavity and adapted for fluid communication with the clutch slave cylinder, a second port fluidly communicating with the fluid cavity and adapted for fluid communication with the clutch footpedal, and a third port fluidly communicating with the fluid cavity and adapted for fluid communication with a fluid bypass, and a movable piston disposed in the fluid cavity of the clutch master cylinder to act as a switch valve to allow fluid flow from the second port to the third port when the electronic clutch actuator is being used and to allow fluid flow from the second port to the first port when the electronic clutch actuator is not being used.

A hydraulic drive system includes a unidirectional pump, a charge pump configured to supply an input of the unidirectional pump with a hydraulic fluid pressurized with a charge pressure, a hydraulic motor, and a flow control valve configured to meter a flow of hydraulic fluid from an output of the unidirectional pump to a fluid input of the hydraulic motor. The hydraulic motor comprises a fluid output configured to be in direct fluid communication with the input of the unidirectional pump. Fluid delivery systems include hydraulic drive systems.

This clutch actuator includes a hydraulic pressure generating mechanism (51) configured to operate a clutch (26) to provide a connected state or a disconnected state, a motor (52) configured to generate a rotary driving force for driving the hydraulic pressure generating mechanism (51) to a driving shaft (52a), a transmission mechanism (54) configured to transmit the rotary driving force generated in the driving shaft (52a) of the motor (52) to a driven member (54b) parallel to the driving shaft (52a) in an axial direction and disposed coaxially with a cylinder main body (51a), and a conversion mechanism (55) configured to convert the rotary driving force transmitted to the driven member (54b) into a reciprocal driving force of a piston (51b) in a stroke direction, wherein the hydraulic pressure generating mechanism (51), the motor (52), the transmission mechanism (54) and the conversion mechanism (55) are integrated as a unit.

A hydraulic drive system includes a unidirectional pump, a charge pump configured to supply an input of the unidirectional pump with a hydraulic fluid pressurized with a charge pressure, a hydraulic motor, and a flow control valve configured to meter a flow of hydraulic fluid from an output of the unidirectional pump to a fluid input of the hydraulic motor. The hydraulic motor comprises a fluid output configured to be in direct fluid communication with the input of the unidirectional pump. Fluid delivery systems include hydraulic drive systems.

The hydromechanical device (102) for supplying each of two opposing active chambers (vr1ca1, vr1ca2) of a double-acting receiving cylinder (vr1) for servo-controlled operation of at least one first output rod (vr1ts1, vr1ts2) INCLUDES: a first double-acting generating cylinder (vg1) INCLUDING a first movement input rod (vg1te1) which is rigidly connected to a first piston (vg1p1) that delimits two first opposing passive chambers (vg1cp1, vg1cp2), each of which is selectively connected to at least one of THE two opposing active chambers of the receiving cylinder (vr1); and an assembly (110) for driving the first rod (vg1te1) of the first generating cylinder (vg1), INCLUDING a movement-transforming screw-nut assembly (112, 114), one movement output component (114) of which is rigidly connected to the first rod (vg1te1) of the first generating cylinder (vg1) and the other movement input component (112) of which is rotated by a drive motor (m1).