In one embodiment, a centrifugal force generating device comprises a first hydraulic rotor, a second hydraulic rotor, and one or more hydraulic control valves. The first hydraulic rotor comprises a first mass and is configured to rotationally drive the first mass around a first axis of rotation using a first flow of hydraulic fluid through the first hydraulic rotor. The second hydraulic rotor comprises a second mass and is configured to rotationally drive the second mass around a second axis of rotation using a second flow of hydraulic fluid through the second hydraulic rotor. The one or more hydraulic control valves are configured to control the first flow of hydraulic fluid through the first hydraulic rotor and the second flow of hydraulic fluid through the second hydraulic rotor.

A shaking unit for the generation of one-dimensional oscillating movements of a machine part mass is provided having a coupling part for mechanical coupling to the machine part mass, a counter-mass which is coupled resiliently to the coupler part and, via the latter, to the machine part mass, and a drive system which acts in a sprung manner between the coupler part and the counter-mass. The coupling part may surround the counter-mass as a frame. At least one of two pneumatic springs of the drive system, which are arranged on both sides of the counter-mass, is loaded with a minimum and/or with a maximum load pressure of the pneumatic springs depending on an oscillation state.

The present invention relates to a vibration generator, an more particularly to a technology in which an actuating shaft protrudes from the opposite ends of a housing such that vibrations generated from the actuating shaft are alternately output in opposite directions of the housing so as to improve vibration efficiency and such that a single vibration generator simultaneously applies the vibrations to a plurality of external objects so as to additionally enhance an economic effect. Furthermore, the present invention relates to a technology in which an actuating shaft protrudes from the opposite ends of a housing, thereby enabling stable installation. In addition, the present invention relates to a technology in which a fluid supply tube is configured to be movable in the axial direction of an actuating shaft so as to prevent breakage of the connected portion of the fluid supply tube, which might otherwise occur during the operation of the vibration generator.

A device and a method for generating percussive pulses or vibrations for a construction machine, in which a piston is reversibly reciprocated in a working space in a housing between a first reversal point and a second reversal point, wherein, for the purpose of generating the percussive pulses or vibrations, the piston is set into a reversible movement by means of a pressure fluid and the said pressure fluid is led into and out of the working space in the region of the first reversal point and the second reversal point. The position of the piston is detected by way of a measuring means, in that depending on the detected position of the piston a control unit controls at least one controllable valve, through which pressure fluid is led into and/or out of the working space, wherein by the control unit the movement of the piston is controlled.

A modular motor is disclosed that includes a piston/harmonic drive assembly that is axially cycled. The piston/harmonic drive assembly is coupled to a ball transfer arrangement that converts the axial motion into rotary motion to rotate a rotor that can be used to rotate a drill bit.

A mechanism with a base; a pendulum mounted pivotally relative to the base about a pendulum axis; first/second eccentric elements generating first/second moments of gravitational force about first/second axes; and a synchronization system of the first/second eccentric elements according to a synchronized counter-rotating rotational movement. The pendulum axis and eccentric elements' axes are parallel and arranged in the plane integral to the pendulum. The eccentric elements' axes are supported by the pendulum, above and below the pendulum axis. The eccentric elements are movable in synchronized counter-rotating rotation, with cross-centrifugations, the pendulum pivots alternately on one side then the other, amplifying the rotational movement of the eccentric elements, by simultaneous cross-thrusts of the pendulum against the eccentric elements' axes, and by the transmission of torque to the synchronization system, and the energy generated by centrifugation within the mechanism is recoverable by coupling an energy recovery system to the synchronization system.

An apparatus is provided for compacting the ballast bed of a track, comprising a machine frame which is movable on the track with a stabiliser unit which runs on rollers on the track and is equipped with a vibration drive for producing a vibration in a plane parallel to the track. The stabiliser unit is preferably equipped with tension rollers engaging around the rail head. The stabiliser unit is linked in a height-adjustable manner to the machine frame with an adjusting drive and can be moved against the track under load. In order to provide advantageous constructional conditions it is provided that the vibration drive comprises at least one cylinder vibrator which is formed by a hydraulic cylinder and is triggered via a proportional or servo valve.

The invention relates to a device and a method for generating percussive pulses or vibrations for a construction machine, with a housing, a piston which is reversibly reciprocable in a working space in the housing between a first reversal point and a second reversal point, a pressure fluid supply, through which pressure fluid can in each case be led into and out of the working space in the region of the first reversal point and the second reversal point, wherein the piston can be set into the reversible movement in order to generate the percussive pulses or vibrations, at least one controllable valve, through which the pressure fluid can be led into and/or out of the working space, and a control unit which is connected to the at least one controllable valve, wherein by the control unit the movement of the piston in the working space can be controlled and changed. According to the invention provision is made in that the control unit is designed to move the piston at a frequency that corresponds to a resonance frequency of an overall arrangement comprising the piston and the pressure fluid.

A pneumatic vibration device with a rotatable piston shaft comprises a piston body and a gas diverter. The piston body comprises a piston shaft, an input shaft and a piston cylinder body. The piston shaft comprises a hollow spindle with two ends connected to a first piston and a second piston through connection bearings respectively. The first piston and the second piston are connected through an inner sleeve. The spindle is connected to a rotary connection member. The input shaft stretches into the inner sleeve and is matched and connected with the rotary connection member. The gas diverter comprises a first gas diversion port and a second diversion port. The pneumatic vibration device is compact in structure and high in adaptability, and can realize rotation and vibration of drilling tools.

A multi-input, multi-output phononic system including a first interface surface and a second interface surface that respond to at least one of a pressure gradient or a velocity gradient in a wave of a turbulent fluid flow or a laminar fluid flow, the pressure gradient or the velocity gradient associated with complex motion of the flow exhibiting a plurality of frequencies exerted on one or more of the interface surfaces; and a subsurface feature extending from the interface surfaces, the subsurface feature comprising a phononic crystal or locally resonant metamaterial adapted to receive one or more of the pressure gradient or the velocity gradient from the fluid flow via the interface surfaces and to alter one or more of a phase and an amplitude of a plurality of frequency components of the fluid flow.