A linear compressor includes a linear motor including a mover that reciprocates with respect to a stator; a compression unit configured to define a compression space in a cylinder while a piston connected to the mover reciprocates in the cylinder; a frame disposed outside of the cylinder; a plurality of discharge covers that define discharge spaces sequentially receiving refrigerant discharged from the compression space; and a gas bearing configured to guide part of refrigerant accommodated in a discharge any one of the plurality of discharge covers to lubricate between the cylinder and the piston with the refrigerant. The discharge cover structure is configured to restrict heat transfer between the discharge covers and the frame.

A linear compressor includes a linear motor including a mover that reciprocates with respect to a stator; a compression unit configured to define a compression space in a cylinder while a piston connected to the mover reciprocates in the cylinder; a frame disposed outside of the cylinder; a plurality of discharge covers that define discharge spaces sequentially receiving refrigerant discharged from the compression space; and a gas bearing configured to guide part of refrigerant accommodated in a discharge any one of the plurality of discharge covers to lubricate between the cylinder and the piston with the refrigerant. The discharge cover structure is configured to restrict heat transfer between the discharge covers and the frame.

Each of mechanical seal devices 7 of a rotary joint 1 includes a first shaft side seal ring 71 and a second shaft side seal ring 72 attached to a shaft body 5, and a first case side seal ring 73 and a second case side seal ring 74 attached to a case body 2. The first shaft side seal ring 71 and the second shaft side seal ring 72 have contact surfaces 71b and 72b axially facing each other and coming into contact with each other, and grooves 421c and 421d for forming a second communication flow passage 42 connecting a second outer flow passage 32 and a second inner flow passage 62 are formed in both the contact surfaces 71b and 72b.

A rolling bearing unit includes: an inner ring member having a recess on a first side in an axial direction along a rotation axis, which is recessed toward a second side in the axial direction; an outer ring member on an outer peripheral side of the inner ring member; a rolling body between the inner ring member and the outer ring member; a non-contact transmitter using electric field coupling capable of transmitting at least one of an electric power or a signal and including a stationary-side transmission part including a stationary-side electrode and a rotary-side transmission part including a rotary-side electrode facing the stationary-side electrode; and a covering member supported by the first side of the outer ring member in the axial direction, covering the first side of the inner ring member in the axial direction, and fixing the stationary-side transmission part to the first side in the axial direction.

A bearing system that accepts a journal of a roll includes a housing defining a cavity and having a forward wall that defines an opening into the cavity, the opening configured to accept the journal through the opening and into the cavity. A sleeve is positioned within the cavity of the housing, the sleeve configured to surround the end of the journal. A first seal is positioned within the cavity of the housing adjacent to the forward wall of the housing, the first seal having an engagement surface. A second seal is positioned within the cavity of the housing and operably connected to the sleeve, the second seal having an engagement surface in contact with the engagement surface of the first seal.

A steering actuator for rear axle steering of a motor vehicle has a spindle drive (5) which comprises pushrods (9) which are connected to a threaded spindle (16) and which are mounted in a housing (6) by means of plain bearings (18), allowing the passage of air, and are connected at each end thereof to an attachment element (12) provided for coupling to a chassis suspension arm, wherein a gaiter (19, 20) is connected on the one side to the housing (6) and on the other side to one of the attachment elements (12) in each case. Each plain bearing (18) is designed as a bearing allowing one revolution of the threaded spindle (16), wherein at least one longitudinal groove (21) abuts one guide bush (23) of the plain bearing (18).

A damper includes: cylindrical damper body, damper body including inner ring and outer ring located concentrically, arc springs located side by side in circumferential direction between inner and outer rings, and slits that separate inner ring, outer ring, and arc springs; sealers on both sides of damper body in axial direction, sealers including sealing surfaces, sealing surfaces facing open ends of slits in axial direction, with gaps between sealing surfaces and open ends of slits; and viscous fluid that fills slits and gaps. Arc springs include first arc spring and second arc spring located side by side in circumferential direction. Each slit includes: inner slit portion that separates first arc spring and inner ring; outer slit portion that separates second arc spring and outer ring; connecting portion that connects inner slit and outer slit portions. Connecting portion includes restrictor that restricts viscous fluid movement between inner and outer slit portions.

A wheel hub bearing for motor vehicles including a rotatable hub provided with a flange for the engagement of the hub to a wheel of a vehicle and provided with a radially outer free portion and a bearing unit provided with a radially outer ring for the engagement of the wheel hub bearing to a knuckle of the vehicle and a radially inner rotatable ring angularly connected to the hub. Furthermore, the wheel hub bearing has a device for detecting a vehicle parameter and provided with an encoder and a sensor in communication with the encoder. The encoder is ridgidly coupled to the radially outer free portion of the flange to jointly rotate with the hub.

A wheel hub bearing for motor vehicles including a rotatable hub provided with a flange for the engagement of the hub to a wheel of a vehicle and provided with a radially outer free portion and a bearing unit provided with a radially outer ring for the engagement of the wheel hub bearing to a knuckle of the vehicle and a radially inner rotatable ring angularly connected to the hub. Furthermore, the wheel hub bearing has a device for detecting a vehicle parameter and provided with an encoder and a sensor in communication with the encoder. The encoder is ridgidly coupled to the radially outer free portion of the flange to jointly rotate with the hub.

In one aspect, an apparatus for retaining lubricant in a wheel hub assembly, the wheel hub assembly including a wheel hub and a spindle nut for securing the wheel hub to a vehicle spindle. The apparatus includes an annular lubricant seal, a mounting portion of the lubricant seal to be mounted to the wheel hub, a central opening of the lubricant seal to receive a running surface of the spindle nut, and a sealing portion of the lubricant seal extending around the central opening of the lubricant seal. The sealing portion is configured to form a dynamic seal with the running surface of the spindle nut and keep the lubricant from escaping between the sealing portion of the lubricant seal and the running surface of the spindle nut as the wheel hub rotates around the vehicle spindle.