Abstract: A retainer of an outer ring guide type, includes a retainer guide surface, a relief surface (edge relief groove), and an axial groove. The retainer guide surface is provided on at least one axial end portion of a retainer outer diameter surface and is guided by the outer ring. The relief surface is formed on the retainer outer diameter surface along a circumferential direction, located on an axial center side with respect to the retainer guide surface, and has an outer diameter smaller than that of the retainer guide surface. The axial groove extends from the pockets to an axial end on the retainer outer diameter surface, forms an axial step portion by axially traversing the retainer guide surface, and has a groove bottom on a radial inner side with respect to the relief surface.

Abstract: A synthetic resin rolling bearing retainer is to be arranged between an inner ring and an outer ring of a rolling bearing. A plurality of guided portions protruding radially outward from an outer diameter surface of the retainer is provided along a circumferential direction of the outer diameter surface. Each of the guided portions has a guide surface protruding to be in sliding contact with the outer ring, a chamfered portion formed at an edge portion of the guide surface, and a groove portion formed at a portion of the guide surface in an axial direction. The guide surface and the chamfered portion have surface properties where an arithmetic average roughness Ra is 1.0 to 9.8 ?m and a maximum height Rt is 10.1 to 102.9 ?m. A parting line is provided radially inside the guide surface.

Abstract: A retainer of an outer ring guide type, includes a retainer guide surface, a relief surface (edge relief groove), and an axial groove. The retainer guide surface is provided on at least one axial end portion of a retainer outer diameter surface and is guided by the outer ring. The relief surface is formed on the retainer outer diameter surface along a circumferential direction, located on an axial center side with respect to the retainer guide surface, and has an outer diameter smaller than that of the retainer guide surface. The axial groove extends from the pockets to an axial end on the retainer outer diameter surface, forms an axial step portion by axially traversing the retainer guide surface, and has a groove bottom on a radial inner side with respect to the relief surface.

Abstract: A synthetic resin rolling bearing retainer is to be arranged between an inner ring and an outer ring of a rolling bearing. A plurality of guided portions protruding radially outward from an outer diameter surface of the retainer is provided along a circumferential direction of the outer diameter surface. Each of the guided portions has a guide surface protruding to be in sliding contact with the outer ring, a chamfered portion formed at an edge portion of the guide surface, and a groove portion formed at a portion of the guide surface in an axial direction. The guide surface and the chamfered portion have surface properties where an arithmetic average roughness Ra is 1.0 to 9.8 ?m and a maximum height Rt is 10.1 to 102.9 ?m. A parting line is provided radially inside the guide surface.

Abstract: Retained austenite amounts of surface layer parts of an inner ring and an outer ring are set at more than 0% by volume. A ball (rolling element) is obtained by processing a raw material including alloy steel in which an Si content is 0.3 to 2.2% by weight and an Mn content is 0.3 to 2.0% by weight and Si/Mn is 5 or less (by mass) and then performing thermal treatment including carbonitriding or nitriding. Si.Mn nitride including nitride of silicon (Si) and nitride of manganese (Mn) is present in a rolling surface of the ball in a range of 1.0 to 20.0% by area. An N content of a surface layer part of the ball is 0.2 to 2.0% by weight, and a retained austenite amount is 0 (exclusive) to 50% (inclusive) by volume and the following formula (1) is satisfied.

Abstract: The present invention provides a rolling bearing capable of suppressing the generation of retainer noise and abnormal vibration by specifying the circumferential width of axial grooves formed on the guide face of an outer ring guide retainer or an inner ring guide retainer. In a rolling bearing 1 according to the present invention, axial grooves 13 are formed on the outer circumferential face of the outer ring guide type retainer 10 thereof.

Abstract: The present invention provides a rolling bearing capable of suppressing the generation of retainer noise and abnormal vibration by specifying the circumferential width of axial grooves formed on the guide face of an outer ring guide retainer or an inner ring guide retainer. In a rolling bearing 1 according to the present invention, axial grooves 13 are formed on the outer circumferential face of the outer ring guide type retainer 10 thereof.

Abstract: A positioning apparatus has a stage, guide elements provided on both ends of the stage, and drive elements which are provided at one of both ends of the stage and move the stage along the guide elements. Like linear guide rails 61A, 61B and linear guide bearings 23A, 23B, two guide elements are provided in an area where a ball screw shaft 52 serving as a drive element is placed. One guide element is provided in an area where a non-drive element is provided.

Abstract: A positioning apparatus has a stage, guide elements provided on both ends of the stage, and drive elements which are provided at one of both ends of the stage and move the stage along the guide elements. Like linear guide rails 61A, 61B and linear guide bearings 23A, 23B, two guide elements are provided in an area where a ball screw shaft 52 serving as a drive element is placed. One guide element is provided in an area where a non-drive element is provided.