A radial force device for a contour measuring instrument for measuring a contour of a shaft-shaped workpiece which can be rotated about an axis of rotation. The radial force device has a clamping body, a force introduction roller, at least one counter-roller and a coupling device. The clamping body is shaped for fitting radially around a workpiece portion, received in the contour measuring instrument, of the workpiece. The force introduction roller is designed to apply a mechanical radial force to the workpiece in order to apply a load to the workpiece, wherein the force introduction roller is mounted in a radially movable manner on the clamping body. The counter-roller is mounted in the clamping body and designed to support the workpiece during the application of the force. The coupling device is shaped for coupling the clamping body to the contour measuring instrument.

The invention relates to elastic guiding device to support a mass with respect to a base in a support direction, wherein the stiffness in support direction compared to stiffness in other direction, for example the stiffness in vertical direction compared to the stiffness in horizontal directions is substantially increased. The invention further relates to a positioning device comprising at least one elastic guiding device, and a lithographic apparatus comprising such positioning device.

This percussion apparatus includes a striking piston mounted so as to be displaced inside a piston cylinder and arranged to strike a tool; and a guide bearing comprising a guide surface configured to guide the striking piston during the displacements of the striking piston in the piston cylinder. The guide bearing includes a centering device configured to center the striking piston in the piston cylinder, the centering device comprising centering chambers formed in the guide surface and distributed around the striking piston, each centering chamber being fluidly connected to a high pressure fluid supply circuit; and at least one discharge groove formed in the guide surface of the guide bearing and located proximate to at least one of the centering chambers, the at least one discharge groove being fluidly connected to a low pressure circuit.

A tire testing device includes a road surface, a carriage capable of traveling along the road surface in a state where a test tire is in contact with the road surface, and a guide mechanism configured to guide movement of the carriage. The guide mechanism includes a rail, and a runner. The runner includes a first roller that rolls on an upper surface of a head of the rail, and a second roller that rolls on a lower surface or a side surface of the head of the rail. The tire testing device includes a first guide mechanism and a second guide mechanism. In the first guide mechanism, the rollers except for the first roller are disposed only on one side of the rail, and in the second guide mechanism, the rollers except for the first roller are disposed only on an other side of the rail.

The present disclosure relates to the technical field of rollers, and provides a roller assembly, including: a fixing cover, a roller, a round magnet and a rotating shaft. The roller assembly further includes a bearing. The bearing is coaxially connected to an end of the rotating shaft; the roller is coaxially sleeved on an outer surface of the bearing; and the round magnet is coaxially connected to another end of the rotating shaft. By this way, the bearing structure is more precise, thereby enabling a better customer experience, a longer product life, and a simple structure for easy installation.

The invention relates to elastic guiding device to support a mass with respect to a base in a support direction, wherein the stiffness in support direction compared to stiffness in other direction, for example the stiffness in vertical direction compared to the stiffness in horizontal directions is substantially increased. The invention further relates to a positioning device comprising at least one elastic guiding device, and a lithographic apparatus comprising such positioning device.

Techniques are disclosed for systems and methods for nested gimbal assemblies. A gimbal system may include a base, a yoke, and a gimbal assembly rotatably connecting the yoke to the base. The gimbal assembly may include a motor, a bearing, and a ferrofluid seal. The motor may be configured to rotate the yoke relative to the base about a rotational axis. The bearing may be seated within the base and permit rotation of the yoke relative to the base about the rotational axis. The ferrofluid seal may be positioned to seal an interface between the yoke and the base. The motor may be positioned within an inner diameter of the bearing. The bearing may be positioned within an inner diameter of the ferrofluid seal.

A magnetic device for centring a shaft on a predetermined axis in a clockwork movement includes at least one first magnetic bearing provided with a magnet to exert an attractive force on a first ferromagnetic end pivot of the shaft. The first magnetic bearing includes a central part made of soft ferromagnetic material mounted between the magnet and the first end pivot of the shaft. The central part is positioned centrally in a washer made of non-magnetic material so as to centre the magnetic field flux generated by the permanent magnet through the central part in order to magnetically attract the first end pivot of the shaft on the predetermined axis. The diameter of the central part can be identical to, or 0 to 20% less than, or 0 to 20% greater than, the diameter of the first end pivot.

An apparatus having a shaft, a bearing sleeve for rotatably supporting the shaft, a housing, in which at least one part of the bearing sleeve is arranged, and a sealing element, which seals a gap between a wall of the housing and the bearing sleeve. The sealing element divides the gap gas-tight into a first partial space adjacent to the front side of the sealing element and a second partial space adjacent to the back side of the sealing element, the sealing element having a flexible part, which is in contact with the wall of the housing and/or the bearing sleeve, and the housing having a first barrier gas inlet for introducing barrier gas into the first partial space as well as a second barrier gas inlet for introducing barrier gas into the second partial space.

A cantilever linear motion reference device employing two-layer air suspension. By means of a two-layer force sealed air suspension structure, the invention realizes two-dimensional air suspension support and motion guiding and improves the rotational stiffness per unit for an air suspension working surface. By combining accurate driving and feedback control, the invention achieves high speed, high acceleration, high frequency motion, and enables construction of a small-volume, long cantilever, high torque load two-dimensional motion reference device.