A parallel bearing includes a rotary shaft bearing and a stator bearing, wherein the rotary shaft bearing is a contact bearing, and the rotary shaft bearing is sleeved on a rotary shaft; and the stator bearing is a non-contact bearing, the stator bearing is sleeved on the rotary shaft bearing, and a clearance is provided between the stator bearing and the rotary shaft bearing. The parallel bearing is cost-effective, reduces the relative rotational speed of each stage of bearing, breaks through the limitation of the theoretical DN factor and has the low dependency on the lubricating oil. In the rotor system having the parallel bearing, rotational speeds of multiple parallel bearings on the same rotary shaft can be adaptively adjusted to achieve the synchronous rotation, and thus the rotor system has the desired stability in high-speed operation.

According to the embodiment of the present disclosure, a hydraulic bearing (1) is provided, comprising an inner core (2), an outer shell (3) which radially surrounds the inner core (2), an elastomer body (4) which resiliently interconnects the inner core (2) and the outer shell (3) in order to allow a relative displacement between the inner core (2) and the outer shell (3), a first working chamber (5) and a second working chamber (6) which are fluidically interconnected by means of a working channel, a bypass chamber (8) which is connected to the first working chamber (5) by means of a first bypass channel (9), wherein the first working chamber (5) and the second working chamber (6) are configured such that an amount of a volume change in the case of a displacement of the inner core (2) relative to the outer shell (3), in a predetermined radial direction, is larger for the first working chamber (5) than for the second working chamber (6).

A plain bearing of a planetary gearbox has first and second rotationally connected components. Oil adjacent an oil feed pocket of the first component is directed into the bearing clearance between the components by a first line that opens into the pocket. The line includes a first portion and a downstream second portion. The flow cross section of the first portion is smaller than the flow cross section of the second portion. The flow cross section for the oil, in the feed direction, in the circumferential direction of the clearance and in the main rotation direction of the second component relative to the first component increases more than counter to the main rotation direction of the second component, or in the circumferential direction of the clearance and counter to the main rotation direction of the second component increases more than in the main rotation direction of the second component.

A supporting device including an installation assembly; a first supporting arm assembly having a longitudinal direction, a first end, and a second end; a switching bracket; a bearing unit pivotally connected to the switching bracket; and at least one gas spring is provided. The first end is pivotally connected to the installation assembly. The switching bracket is pivotally connected to the second end of the first supporting arm assembly. The gas spring is disposed in the first supporting arm assembly and is respectively connected to the switching bracket and the installation assembly to provide a supporting force. Each gas spring has a hollow tube, a piston rod, and a compression spring. The piston rod is slidably disposed through the hollow tube and has a head. The head may be varied between maximum and minimum protruding positions relative to the hollow tube. The compression spring is sleeved on the piston rod.

A non-contact air bearing having electrostatic discharge properties may comprise: a porous media element having a bearing surface; a supply line configured supply an externally pressurize gas or fluid to the porous media; and an electrostatic dissipative porous bearing layer on the bearing surface of the porous media element; wherein the externally pressurized fluid flows through the porous media element and creates a thin film between the electrostatic dissipative layer and a substrate supported by the air bearing.

A high-precision air floating motion platform and method for wafer test, wherein the air floating motion platform includes: a base; a beam installed on the base; a sliding table configured to carry a wafer; a linear motor configured to drive the sliding table to slide along the beam; at least three sensors configured to detect a vertical straightness of the wafer; air bearings including a first air bearing, a second air bearing and a third air bearing; the air bearings being configured for suspension of the sliding table; and a compensation device configured to compensate the vertical straightness of the wafer based on a real-time data detected by the sensors.

An actuator comprising a linear electrical machine (LEM) having a stator with a stator bore and a translator axially movable within the stator bore and defining a magnetic circuit airgap therebetween, at least one fluid bearing journal formed on the translator, at least one fluid bearing providing a bearing gap adjacent the translator to allow the translator to move axially within the stator bore, a preload chamber for applying a preload force to the translator, wherein the preload chamber is defined by a side wall, a first end wall and a second end wall at least part of which is movable with the translator, and wherein the bearing gap and the magnetic circuit airgap are coaxial.

An actuator comprising a linear electrical machine (LEM) having a stator with a stator bore and a translator axially movable within the stator bore and defining a magnetic circuit airgap therebetween, at least one fluid bearing journal formed on the translator, at least one fluid bearing providing a bearing gap adjacent the translator to allow the translator to move axially within the stator bore, a preload chamber for applying a preload force to the translator, wherein the preload chamber is defined by a side wall, a first end wall and a second end wall at least part of which is movable with the translator, and wherein the bearing gap and the magnetic circuit airgap are coaxial.

A gantry-type positioning device includes a planar base parallel to first and second directions. Two first linear axes are arranged in the first direction, each having a first linear drive. A frame held by the first linear axes is movable in the first direction, and comprises two transverse and two longitudinal beams. The transverse beams carry second linear axes with second linear drives parallel to the second direction, so that a movable element arranged between the transverse beams is movably held by the second linear actuators. The frame is flexibly constructed such that the movable element is rotatable about a third direction which is perpendicular to the first and second directions. With respect to the third direction, the movable element is guidable by a guide surface of only one of the transverse beams serving as a guide beam for the movable element.

A gas bearing for a compressor includes a bearing portion and a sealing portion mounted to a bearing housing of the compressor via one or more dampers, and the sealing portion being fixedly connected to the bearing portion, and a vent with an inlet in the bearing. The bearing portion has an inner radial surface for radially supporting a shaft of the compressor. The sealing portion has a sealing surface. The inlet of the vent disposed between the inner radial surface and the sealing surface. The sealing surface and a rotating surface form a path that extends along the sealing surface. The path extending from a pressurized volume of the compressor to the vent, and the pressurized volume containing a fluid.