An air bearing for calibrating a force measurement device comprises an inner wall, an outer wall, an upper wall, a lower wall, an internal chamber, an object retention opening, and a plurality of air outlets. The inner wall and outer wall each have a cylindrical shape with the outer wall being concentric with the inner wall. The upper wall and lower wall each have an annular shape and are attached to the inner wall and the outer wall. The internal chamber is formed by inner surfaces of the four walls, and is configured to retain compressed air. The object retention opening is formed by an outer surface of the inner wall and is configured to receive and retain an object. The air outlets are positioned along the inner wall and are configured to allow compressed air to flow from the internal chamber to the object retention opening.

The invention relates to a method for determining shifts in position in at least two different spatial directions between a first element and a second element which are movable relative to each other, with at least two sensors which measure contactlessly and are spaced, in the at least two different spatial directions, from at least two standards which are fixed to the second element, sensor areas of the at least two sensors opposing the at least two standards in the respective spatial direction and sensing said standards, wherein: the at least two sensors scan the at least two standards and generate, in interaction with the at least two standards, output signals with which in combination an absolute position of the second element is determined, said absolute position being associated with a linear movement in a further spatial direction or with a rotary movement, andwherein the output signals of the at least two sensors are also used to determine values which characterise the distance between the respective sensor and the corresponding standard of the second element in the associated spatial direction, are corrected as a function of the determined absolute position of the second element, and from which the shift in position of the second element relative to the first element in the respective spatial direction is determined.

A T-film bearing for a vibration fixture including a bottom plate, two spaced apart middle plates positioned on the bottom plate, two spaced apart top plates positioned on the middle plates in which the middle plates and the top plates form a T-shaped linear channel for movement of a T-shaped guide member of a slip plate, and oil distribution grooves positioned on a top surface of each of the top plates and the bottom plate defining an independent pressure area, and each groove having a dedicated flow restrictor for supplying lubricating oil to the groove for lubricating reciprocating travel of the guide member within the linear channel and the slip plate on the top plates.

A bearing system for rock mechanics test under high temperature and high pressure multi-field coupling includes a force sensor lifting seat and a jack. The force sensor lifting seat includes a connecting disk connected with the jack, a support disk, and an operation channel. A groove dented downwards is arranged on the connecting disk, the support disk is disposed in the groove and freely propped upon the connecting disk; through holes of the connecting disk and the support disk form a control operation channel; and a limiting device is arranged for preventing an MTS triaxial force sensor from disengaging from the support disk. A bolt hole of the force sensor can be aligned with a mounting hole on a solid steel column by rotating the connecting disk for convenient and accurate bolting.

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 rheometer has rotary rheometer and a linear DM(T)A analysis unit. A measuring shaft of the rotary rheometer carries a measuring part that faces a measuring part carried on an adjusting rod of the linear analysis unit. The sample under test is placed in a measuring gap between the measuring parts. The DM(T)A analysis unit has a linear motor, in particular magnetically operated, with a stator and a slider, and a magnetically-operated gravitational compensation unit, by way of which it is possible to compensate for the weight force of the adjusting rod, the measuring part on the adjusting rod, the slider, and any optional the components fastened to the slider.

A suspension assembly is described. A suspension assembly including a support member; a moving member; one or more bearings; and one or more bearing limiters. The one or more bearings between the support member and the moving member to space the support member and moving member by a bearing distance about the z axis. And, the one or more bearing limiters between the first and second members to limit movement of the support member and moving member about the z axis to a gap distance that is less than the bearing distance.

The present invention relates to a rotary assembly (1), in particular for a rheological measurement apparatus, comprising: a stator (3), a rotor (2) that can rotate with respect to the stator (3), the rotor (2) being axially retained by an axial retaining means (4) preventing the movement of the rotor (2) along the axis of rotation (A) thereof, the axial retaining means (4) comprising a flexible rod suitable for being attached to a frame (5) and which allows a radial movement of the rotor (2), a magnetic bearing comprising a rotor element (6) made of magnetic material mounted on the rotor (2) and a stator element (7) made of magnetic material mounted on the stator (3), at least one of the rotor and stator elements made of magnetic material being a spherical magnet,
wherein the rotary assembly (1) has a stable position in which the rotor (2) is aligned with the axis of rotation (A) thereof, and the elements made of magnetic material are facing each other along the axis of rotation (A) of the rotor and are separated from each other by a given distance (M), and wherein the elements made of magnetic material are configured to attract each other, so as to generate a return force which opposes the axial misalignment of said rotor (2). The invention also relates to a rheological measurement apparatus comprising at least one such rotary assembly (1).

In the linear motion guide unit, a retainer plate for retaining rolling elements, or rollers, is prevented from deformation so as to smoothly guide the rollers. The retainer plate is composed of a retainer member, frame members fitted into respective through holes formed in the retainer member, and a fixing member disposed in a longitudinally extending recess of the retainer member. The frame members form a predetermined gap between the fixing member and a carriage. Tightening forces of fastening bolts are not applied to the retainer member, thereby avoiding deformation of the retainer member.

Disclosed is a flexible-pivot mechanical component of the type with separate intersecting blades, particularly for timepieces. The mechanical component includes an attachment portion and a movable portion that are connected by first and second resilient blades that intersect in a contactless manner at an intersecting point. The flexible-pivot mechanical component is combined with an adjustment unit making it possible to adjust the position of the intersecting point.