A pulley device for a transmission element having a pulley, a bearing, and at least one sleeve mounted freely in the bore of the inner ring of the bearing. The pulley device includes at least one annular protection shield, the shield retained axially in a first element from the pulley and coming into immediate proximity with the other element, the other element having at least one shoulder projecting radially ensuring that it is axially retained with the shield.

A charging roll includes a core member, a rubber base material disposed around the core member, and a surface layer disposed around the rubber base material. The ten point height of irregularities R.sub.Z of a surface of the surface layer is equal to or greater than 3.9 micrometers, and is equal to or less than 6.1 micrometers. The mean spacing between peaks S.sub.m of the surface of the surface layer is equal to or greater than 12.5 micrometers and is equal to or less than 13.5 micrometers.

A roller assembly for a mobile cleaning system for cleaning a work surface can include a drive shaft, a sheath, a bushing, and a bushing shroud. The drive shaft can be rotatable about a drive axis, and the drive shaft can include a driven end and an opposite bushing end. The sheath can be supported by the drive shaft and the sheath can be rotatable with the drive shaft. The sheath can include a shell engageable with the work surface. The bushing can be located about the bushing end of the drive shaft. The bushing shroud can be connected to the bushing. The sheath and the drive shaft can be together rotatable with respect to the bushing and the bushing shroud, the bushing shroud can include an outer portion defining a first radius of curvature and a recessed portion connected to the outer portion.

A pulley assembly for belt tensioners having a bearing unit provided with a rotating outer ring and made of metal, an outer wheel body overmoulded onto the outer ring to rotate with the outer ring and interact with a belt, a gripping surface at the interface between the outer wheel body and the outer ring to prevent circumferential slipping between the outer wheel body and the outer ring; and an axial retainer integral with the outer ring and having two lateral edge members located axially on opposite sides of the gripping surface to engage the outer wheel body and prevent axial movement of the outer wheel body relative to the outer ring.

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.

An object of the present invention is to provide an actuator capable of reducing a shock in acceleration at the time of a turn caused by a load in a lateral direction orthogonal to an axis of the actuator even when the load is excessive while reducing manufacturing cost and manufacturing man-hours, and a tripod structure including the actuator. An actuator according to the present invention includes: a pipe; a ball screw used as a feed screw; a conversion nut used as a feed nut and screwed with the ball screw; a piston fixed integrally to the conversion nut and driven to expand and contract from a free end which is one end of the pipe; and a rolling bearing unit being provided on a tip of the free end of the pipe and including a plurality of roller followers holding the piston movably.

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.

A roller assembly includes a roller having an axial hole and an axle portion disposed in the axial hole to allow the roller to rotate about the axle portion; a sleeve with a first end disposed at a first end of the axle portion and a second end having a fitting portion, the fitting portion being fitted to a carried object, the sleeve has a first blocking portion positioned proximate to a first side of the roller to allow the roller to rotate between the first blocking portion and the fitting portion, wherein one of the axle portion, the axial hole and the first blocking portion has a substance conducive to reduction of friction between the roller and the sleeve.

A bearing includes an outer ring with a first outer roller race, a second outer roller race, and a radially inward facing outer ball race. The bearing includes a first and second inner rings that axially abutting one another at an abutment interface. The first inner ring has a first inner roller race, the second inner ring has a second inner roller race that are disposed in an interior area coaxially with the outer ring. A plurality of first rollers rollingly engage the first outer roller race and the first inner roller race. A plurality of second rollers rollingly engage the second outer roller race and the second inner roller race. A plurality of balls rollingly engage the outer ball race and the inner ball race.

A pulley device configured to support a belt of a chain tensioning idler or a runner roller includes a bearing having inner and outer rings and a pulley having at least one C-shaped pulley part mounted on the bearing outer ring with an inner cylindrical portion of the pulley part press-fitted on the bearing outer ring, the bearing outer ring having a material projection and the inner cylindrical portion of the pulley part having an axial groove configured to allow the material projection to slide axially through the groove when the pulley part is slid axially onto the outer ring, the material projection forming an axial stop for the pulley part when the pulley part is rotated relative to the bearing outer ring.