To provide a compact linear actuator having small back drive force. The linear actuator includes: a hollow rotor that has a magnet fixed to a part of the outer peripheral surface thereof and having an open end and a closed end; a main body that has a hollow structure having an open end and a closed end and rotatably accommodates the rotor in the hollow structure, and is fixed with a stator winding facing the magnet; a linear motion converting section that is arranged in the hollow section of the rotor and is linearly moved in the axial direction by the rotation of the rotor; a linear motion rod that has one end fixed to the linear motion converting section, and the other end extended from the open end of the main body, and has, on the outer periphery thereof, a slide section made to slide in the axial direction with respect to a linear motion seal of the opening of the main body; and a resolver that is configured by a rotator fixed at the radial outer side of the outer peripheral surface of the rotor and on the open end side of the closed end section of the rotor, and a stator fixed to the main body at a part of the angular range on the radial outer side of the rotator, the linear actuator being configured such that the rotor is supported by the main body at the open side and the closed end of the magnet and the stator winding so as to be rotatable about the axis of the rotor, and such that the whole of the hollow rotor is accommodated in the sealed space.

A method includes detecting an out of phase condition and an in-phase condition between a vehicle platform and two or more propulsion units attached to the platform. A first speed from a first propulsion unit is compared to a second speed and a torque of one or more propulsion units is controlled to reduce the out of phase condition and/or the in-phase condition when a difference between the first speed and the second speed is greater than a threshold value. A vehicle includes a platform, two or more propulsion units attached to the platform, and a processor. The processor compares a first speed from a first propulsion unit to a second speed, detects from the comparison an out of phase condition between the platform and the two or more propulsion units, and detects from the comparison an in-phase condition between the platform and the two or more propulsion units.

The present invention relates to an adjustable torsion bar system and an anti-roll method, the adjustable torsion bar system is formed through the adjustable hydraulic connecting rods; and by controlling the flow of the liquid media, the characteristics of the hydraulic connecting rods are changed so that the length of the connecting rods has the characteristics of unchanged, unidirectional follow-up elongation or unidirectional follow-up shortening. Thus, the anti-rolling torsion bar system can provide the bidirectional anti-rolling torque or unidirectional anti-rolling torque to satisfy the safety driving requirements of the railway vehicle on different rails.

The present invention relates to an adjustable torsion bar system and an anti-roll method, the adjustable torsion bar system is formed through the adjustable hydraulic connecting rods; and by controlling the flow of the liquid media, the characteristics of the hydraulic connecting rods are changed so that the length of the connecting rods has the characteristics of unchanged, unidirectional follow-up elongation or unidirectional follow-up shortening. Thus, the anti-rolling torsion bar system can provide the bidirectional anti-rolling torque or unidirectional anti-rolling torque to satisfy the safety driving requirements of the railway vehicle on different rails.

A device for force transfer between a chassis frame and a carriage body of a rail vehicle includes a plurality of lemniscate links which are connected to the chassis frame via first joints, a yoke having a middle linking point in which the carriage body can be mounted, wherein the plurality of lemniscate links are connected to the yoke via second joints and form a Z-shaped assembly, where elastically deformable elements are arranged in the in the yoke and the first and second joints, and includes limiting means for receiving impact loads that exceed the operating load so as to limit the maximum deflection of the middle linking point of the yoke in a tractive force direction parallel to a tractive force acting on the chassis frame.

A device for force transfer between a chassis frame and a carriage body of a rail vehicle includes a plurality of lemniscate links which are connected to the chassis frame via first joints, a yoke having a middle linking point in which the carriage body can be mounted, wherein the plurality of lemniscate links are connected to the yoke via second joints and form a Z-shaped assembly, where elastically deformable elements are arranged in the in the yoke and the first and second joints, and includes limiting means for receiving impact loads that exceed the operating load so as to limit the maximum deflection of the middle linking point of the yoke in a tractive force direction parallel to a tractive force acting on the chassis frame.

Provided is a rail vehicle that efficiently transmits, to a railway vehicle structure, an oscillating force transmitted from a bogie to an underframe via a yaw damper and a yaw damper support portion, and that has sufficient strength. The underframe includes a floor portion, a side beam, and a bolster beam. A side structure is erected on an end portion in a vehicle width direction of the underframe. The bogie supports the underframe from below the underframe. A yaw damper receiving portion is provided to the end portion in the vehicle width direction of the underframe. The yaw damper support portion is fixed to the yaw damper receiving portion. The yaw damper includes one end portion connected to the bogie and the other end portion connected to the yaw damper support portion. The yaw damper is configured to reduce yawing oscillation of the bogie. The yaw damper receiving portion is provided to extend along the side structure, the side beam, and the bolster beam.

Provided is a rail vehicle that efficiently transmits, to a railway vehicle structure, an oscillating force transmitted from a bogie to an underframe via a yaw damper and a yaw damper support portion, and that has sufficient strength. The underframe includes a floor portion, a side beam, and a bolster beam. A side structure is erected on an end portion in a vehicle width direction of the underframe. The bogie supports the underframe from below the underframe. A yaw damper receiving portion is provided to the end portion in the vehicle width direction of the underframe. The yaw damper support portion is fixed to the yaw damper receiving portion. The yaw damper includes one end portion connected to the bogie and the other end portion connected to the yaw damper support portion. The yaw damper is configured to reduce yawing oscillation of the bogie. The yaw damper receiving portion is provided to extend along the side structure, the side beam, and the bolster beam.

An actuator according to the present invention includes a telescopic body, a tank, a first opening/closing valve provided in a first passage that connects a rod side chamber to a piston side chamber, a second opening/closing valve provided in a second passage that connects the piston side chamber to the tank, a pump that supplies a fluid to the rod side chamber, a motor that, drives the pump, an exhaust passage that connects the rod side chamber to the tank, and a valve element provided in the exhaust passage, wherein a telescopic unit is formed by integrating the telescopic body, the first opening/closing valve, and the second opening/closing valve, a driving unit is formed by integrating the pump and the motor, and the telescopic unit and the driving unit are provided as separate bodies.

A railroad car truck including a first side frame, a second side frame, a bolster, and a first plurality of warp restraints, each first warp restraint configured to reduce, inhibit, or minimize warping of the bolster relative to the side frame, and in one embodiment including a first inner bearing race at a first end of the bolster, a second opposing outer bearing race at the first side frame, and a roller positioned in a channel formed by and between the first and second opposing bearing races, and a second plurality of warp restraints, each second warp restraint including a first inner bearing race at a second end of the bolster, a second opposing outer bearing race at the second side frame, and a roller positioned in a channel formed by and between the first and second opposing bearing races.