Selective damping apparatus comprises at least one sensor (7) for detecting, and producing signals indicative of at least the frequency and amplitude of vibrations of a first structural component ("the resonant structure") (6) having one or more resonant frequencies, at least one vibration generator (40) for generating damping vibrations for application to the resonant structure, a controller (8) for controlling the operation of the vibration generator (40) in delayed response to the signals produced by the at least one sensor (7), and wherein at least one of said at least one sensor (7) and of said at least one vibration generator (40) is adapted to operate in co-operation with a second structural component ("the non-resonant structure") (2) relatively insensitive to the resonant frequencies of the resonant structure (6) and connected or coupled to said resonant structure (6) either directly or indirectly via one or more intermediate structural components.

The invention concerns a vibration damper (1) for rails (3) of a railway, resting on sleepers (4) which are situated at a certain distance (10) from one another, which damper (1) is designed to be fixed to said rails between two successive sleepers (4), whereby said damper (1) comprises at least one damping element (7) which must be placed against the rail flange (3a) and/or the top side of the rail foot (3b) of the rail (3), so that the far end (6) of the damping element (7) which is turned away from the rail (3) can freely vibrate.

1. A vibrating grinding machine with a container (1) for receiving the mass to be vibrated and a generator of vibrations (2), characterized in that the container (1) comprises at the bottom (3, 3') a discharge device (14) for the mass to be vibrated, on which is disposed a free internal jacket (10), the bottom being concave, convex or flat-shaped in the region of the discharge device.

Accumulator with cell container(s) incorporates a hardenable casting compound which fixes the respective plate blocks in these containers so that their vibration is virtually prevented. The casting compound at least partially fills the space between the surface of the plate blocks and the pole bridges. Accumulator with one or more cell containers (16) incorporates a hardenable casting compound which fixes the respective plate blocks (15) in these containers in such a way that their vibration is virtually prevented. The casting compound at least partially fills the space between the surface of the plate blocks and the pole bridges (3a, 3b). Casting compound guide elements (7) serve to bound the plate block surfaces which are to be kept free from the casting compound. An Independent claim is also included for a method for producing such a vibration-proof accumulator.

A hydraulic striking device (1) includes a percussion piston (3) which reciprocates in an operating cylinder (2) and strikes a bit (4). The reciprocation is governed by a control valve (10) which is connected to the operating cylinder by a control conduit (27). A holding valve (30) in the control conduit has three connections (27a, 27b, 31): one with the control valve, one with the operating cylinder, and one with the return conduit (17). The connections (27a, 31) which are connected with the operating cylinder and with the control conduit are axially aligned and form the outlets of a hollow cavity (53) in which a preferably spherical movable valve body (54) is disposed, the cross-sectional area of the valve body being smaller than that of the cavity. The connection (27b) with the control valve opens radially into the cavity. If the valve body rests against the valve seat (55) which faces the return conduit, the axis of the connection (27b) passes through that half of the valve body which faces this valve seat. When the striking device operates, energy that is reflected from the bit to the percussion piston can be utilized for the following stroke and thus the total performance of the striking device is increased.

The conveyor has a driver, a useful mass and a counter mass which can be brought into a mutually oppositely oscillating rotational vibrating movement about a central axis of rotation by the driver. The useful mass and the counter mass are mounted so that they can be moved with respect to one another over spring arrangements which are distributed about an axis of rotation. A portion of the useful mass is a pot which is located detachably and exchangeable. The moments of inertia of the useful mass and of the counter mass are in a defined ratio to one another. The pot, which can be mounted exchangeably, is designed so that the moment of inertia of the useful mass and, with that, the ratio of the moments of inertia remain essentially unchanged. The moments of inertia are identical or that the moment of inertia of the useful mass is larger than that of the counter mass.

The device (1) comprises a base (2), carrying a servo motor (3) and attached to the frame of a machine center. A carriage (6) with a vertical shaft (8) on top can be moved on two telescopically arranged rails (4,5) joined horizontally to the base (2). The tool holding elements (16,17) are positioned at the upper end of the shaft (8) and can be fixed with a locking unit (18). A control plate (12) is located at the second rail (5) acting in combination with a guiding roll (10) in order to facilitate a swivel motion of the tool carrier (15).

The invention relates to an ultrasound linear piezoelectric motor comprising an ultrasound oscillator (1) embodied in the form of a piezoelectric plate (4) or a cylinder shell part (3), acoustic oscillation generators (5) and a friction element (6) which frictionally interacts with a driven element (8) and is disposed in a holder. The inventive holder is embodied in the form of an elastic clamp (13) which embraces a driven element, is fixed to the ultrasound oscillator and made of a sound-conducting material.

An apparatus is provided for permitting commercial-off-the-shelf (COTS) electronics to be utilized in harsh environments for which the COTS electronics are not designed, including environments having ambient temperature variations, ambient pressure variations, shock and vibration exposure, environmental contaminants and/or electromagnetic radiation which may be beyond the design specification of the COTS components. The device includes a sealed enclosure having racks or other suitable mounts for the COTS components and having an environmental controlled unit (ECU) which circulates a fluid such as air through the enclosure and through the mounts. The temperature in the enclosure is monitored and the ECU operated to heat or cool fluid passing therethrough to maintain temperature in the enclosure within the design limits of the COTS electronics. A flow channel for ambient fluid, which channel is sealed from the internally circulating fluid, may be provided for removing heat from a cooling unit of the ECU. The enclosure may also have shock mounts, thermal insulation and appropriate shielding to deal with other environmental concerns.

The arrangement has an extractor unit for a cover foil of a component belt. A stretching unit stretches the removed foil, where the stretching unit is movably supported relative to a housing. A sensor (26) is provided for acquiring the position of a clamping unit/clamping piece. A control unit (12) is connected with the sensor and is formed to detect an error condition based on the acquired position of the clamping unit. Independent claims are also included for the following: (1) a control method for an electrical component feeding arrangement (2) a control method for a supply system.