An inner sliding surface for a radial plain bearing, including four circle arcs in at least one cross section. A first arc and a second arc of the four circle arcs lie on different sides of a longitudinal sectional plane which intersects a third arc of the four circle arcs, a fourth arc of the four circle arcs and a common center point of the third arc and the fourth arc. The first arc and a center point of the first arc lie on different sides of the longitudinal sectional plane, and the second arc and a center point of the second arc lie on different sides of the longitudinal sectional plane.

A device for machining rolling element pockets in a workpiece includes a workpiece support, a main spindle, a clamping means fastened to the main spindle, a pressure cylinder and a machining tool. The clamping means includes a receiving arrangement for fastening the clamping means to the main spindle and a pressure plate for pressing the workpiece on the workpiece support. The pressure plate has a passage opening. The pressure cylinder connects the receiving arrangement to the pressure plate. The pressure cylinder is arranged to provide a force to adjust a contact pressure of the pressure plate on the workpiece. The machining tool is fastened to the main spindle and guidable through the passage opening to machine the workpiece.

Provided are a hollow drive shaft using an upsetting method and a method of manufacturing the same, in which hot forging and upsetting processes are applied to both ends of a workpiece so that an outer diameter at both ends of the workpiece is greater than an outer diameter of a middle part of the workpiece, thereby reducing a weight of the drive shaft and enabling the drive shaft to transmit higher driving power. According to the present invention, the upsetting process is applied during the hot forging process to manufacture the hollow drive shaft, portions to be substantially processed are limited to portions at both ends of the workpiece, and the number of upsetting processes is limited to a minimum number (2 or the like), such that initial investment costs and manufacturing costs are low because the number of processes is small.

Provided are a hollow drive shaft using an upsetting method and a method of manufacturing the same, in which hot forging and upsetting processes are applied to both ends of a workpiece so that an outer diameter at both ends of the workpiece is greater than an outer diameter of a middle part of the workpiece, thereby reducing a weight of the drive shaft and enabling the drive shaft to transmit higher driving power. According to the present invention, the upsetting process is applied during the hot forging process to manufacture the hollow drive shaft, portions to be substantially processed are limited to portions at both ends of the workpiece, and the number of upsetting processes is limited to a minimum number (2 or the like), such that initial investment costs and manufacturing costs are low because the number of processes is small.

An improved arrangement and method for preventing bearing ring creep is disclosed herein. The method includes providing a bearing ring including a radial surface having at least one spiral groove. The at least one groove has edge breaks connecting lateral sides to the radial surface of the bearing ring. The method includes arranging the bearing ring inside of a housing or around a shaft such that the radial surface of the bearing ring is arranged adjacent to an inner surface of the housing or an outer surface of the shaft. The edge breaks of the bearing ring frictionally engage with the shaft or the housing to prevent creep of the bearing ring.

A method for surface treatment of a workpiece includes providing the workpiece with hardened workpiece surface, clamping the workpiece, removing material from the hardened workpiece surface with a material removal tool to produce a machined surface with first machining tracks, and rolling the machined surface with a rolling tool by overlapping the first machining tracks to produce a rolled surface with second machining tracks. A distance between the material removal tool and the rolling tool measured in an axial direction of the workpiece is varied in an oscillating manner. The material removal tool may be advanced in the axial direction at a constant speed and the rolling tool may be advanced in the axial direction at an oscillating speed, or the rolling tool may be advanced in the axial direction at a constant speed and the material removal tool may be advanced in the axial direction at an oscillating speed.

A roller for a roller bearing has a first end surface and a second end surface and a rolling surface between the first and second end surfaces. The first end surface has an at least partially ground profile having a non-constant curvature such as a logarithmic profile. Also, an assembly including a grinding tool and a roller with an end surface having a ground non-constant curvature.

A rolling-element bearing includes first and second rings having axial and radial raceways and a row of first radial rolling elements between the axial raceways. At least one row of axial rolling elements is located between a first radial raceway of the first ring and a first radial raceway of the second ring and radially located between an axial guiding face of the first ring and an axial guiding face of the second ring. The axial rolling elements are mounted in the pockets of a cage having a plurality of cage segments, and at least one second radial rolling element is circumferentially interposed between two adjacent cage segments of the plurality of cage segments and radially interposed between the axial guiding faces.

A thin-wall bearing, including an outer ring and an inner ring. The inner ring surface of the outer ring is provided with an outer ring raceway, and the outer ring surface of the inner ring is provided with an inner ring raceway. A steel ball and a cage for installing the steel ball are arranged between the outer ring raceway and the inner ring raceway. A plurality of screw holes are evenly distributed in a circle around the side wall of the outer ring, and knurled screws are provided in the screw holes, respectively. The fit between the knurled screw and the screw hole 10-Φ9 is to be N6/h5. The radial clearance of the thin-wall bearing is greater than or equal to 0.01 but less than or equal to 0.09. A processing method of the thin-wall bearing.

Provided are a hollow drive shaft using an upsetting method and a method of manufacturing the same, in which hot forging and upsetting processes are applied to both ends of a workpiece so that an outer diameter at both ends of the workpiece is greater than an outer diameter of a middle part of the workpiece, thereby reducing a weight of the drive shaft and enabling the drive shaft to transmit higher driving power. According to the present invention, the upsetting process is applied during the hot forging process to manufacture the hollow drive shaft, portions to be substantially processed are limited to portions at both ends of the workpiece, and the number of upsetting processes is limited to a minimum number (2 or the like), such that initial investment costs and manufacturing costs are low because the number of processes is small.