An outer ring case includes an annular guide groove housing an end of each of a plurality of inner rollers. A groove width representing a radial length of the guide groove is greater than a diameter of each inner roller. A radius representing a distance from a bearing axis to an inner wall face of the guide groove that is radially outer is smaller than a distance from the bearing axis to an axial center of each of rollers plus a radius of each inner roller.

The invention relates to a bearing arrangement for a drilling head, through which flushing liquid flows, of a deep drilling device, having multiple radially outer and radially inner bearing rings, wherein the radially outer bearing rings are arranged coaxially over the radially inner bearing rings, wherein, radially between the bearing rings, there are arranged balls which roll in raceways of the bearing rings, and wherein the raceways are delimited axially on both sides by shoulders with mutually opposite shoulder surfaces which run parallel to a bearing longitudinal axis. In order for a bearing arrangement of this type, which, as per the prior art, is adjoined in an axial direction by at least one plain bearing, to be designed to be of short axial extent and in order to simplify the construction, the internal diameter (Di) of the shoulder surfaces of the radially outer bearing rings and the external diameter (Da) of the shoulder surfaces of the radially inner bearing rings are dimensioned such that said shoulder surfaces perform the function of parallel radial plain bearings with a radial clearance (S).

A bearing includes a plurality of rolling elements (26) spaced around a three-hundred and sixty degree circumferential extent of the bearing. An odd, non-singular number of high-points are positioned as near to evenly as possible about the circumferential extent of the bearing, the high-points defined by locations at which rolling elements with the largest diameters are positioned. An odd, non-singular number of low-points are positioned as near to evenly as possible about the circumferential extent of the bearing, the low-points defined by locations at which rolling elements having the smallest diameters are positioned. The odd, non-singular number of high-points is the same as the odd, non-singular number of low-points, and each low-point is positioned as near to evenly as possible between two adjacent high-points.

A bearing includes a plurality of rolling elements (26) spaced around a three-hundred and sixty degree circumferential extent of the bearing. An odd, non-singular number of high-points are positioned as near to evenly as possible about the circumferential extent of the bearing, the high-points defined by locations at which rolling elements with the largest diameters are positioned. An odd, non-singular number of low-points are positioned as near to evenly as possible about the circumferential extent of the bearing, the low-points defined by locations at which rolling elements having the smallest diameters are positioned. The odd, non-singular number of high-points is the same as the odd, non-singular number of low-points, and each low-point is positioned as near to evenly as possible between two adjacent high-points.

A method for assembling a tapered roller bearing includes providing a first rolled-on surface element having a raceway and an axial end surface and mounting a plurality of tapered rollers separated by a plurality of bearing cage segments or by a plurality of roller spacers on the raceway, where each of the plurality of tapered rollers has a frustoconical rolling surface and a circular end surface meeting at a junction. Also placing at least one assembly ring around the plurality of tapered rollers to hold the plurality of tapered rollers against the first rolled-on surface element, and moving a second rolled-on surface element coaxially toward the first rolled-on surface element such that a portion of the second rolled-on surface element contacts the at least one assembly ring and pushes the at least one assembly ring axially off the plurality of tapered rollers.

A method for assembling a tapered roller bearing includes providing a first rolled-on surface element having a raceway and an axial end surface and mounting a plurality of tapered rollers separated by a plurality of bearing cage segments or by a plurality of roller spacers on the raceway, where each of the plurality of tapered rollers has a frustoconical rolling surface and a circular end surface meeting at a junction. Also placing at least one assembly ring around the plurality of tapered rollers to hold the plurality of tapered rollers against the first rolled-on surface element, and moving a second rolled-on surface element coaxially toward the first rolled-on surface element such that a portion of the second rolled-on surface element contacts the at least one assembly ring and pushes the at least one assembly ring axially off the plurality of tapered rollers.

An anti-friction radial bearing has an inner track, an outer track, a pair of extension members, load-carrying rolling members, and double coaxial, cylindrical individual spacers. Each of the extension members has an internal cylindrical hoop surface and is securely mounted to at least one of the inner and outer tracks. The rolling members are equidistantly spaced and rotatably engageable with the inner and outer tracks. The spacers are disposed in pure rolling contact at their ends with the internal cylindrical hoop surfaces of the extension members. Each of the spacers is positioned in pure rolling contact between a corresponding adjacent pair of the rolling members.

A rolling guide apparatus having a first member 1, a second member 2, and a rolling body unit 5, the apparatus including a guide path G of the rolling body unit 5 including a rolling path R configured to have a rolling groove 1a and a rolling groove 3a, and a circulation path C allowing communication between a start point and an end point of the rolling path R, the rolling body unit 5 being configured to have a plurality of first rolling bodies 5a and a plurality of second rolling bodies 5b each composed of an elastic material, at least one second rolling body 5b being always positioned in the circulation path C. The rolling guide apparatus is easy to be assembled and is capable of performing stable operations.

An anti-friction radial bearing has an inner track, an outer track, a pair of extension members, load-carrying rolling members, and double coaxial, cylindrical individual spacers. Each of the extension members has an internal cylindrical hoop surface and is securely mounted to at least one of the inner and outer tracks. The rolling members are equidistantly spaced and rotatably engageable with the inner and outer tracks. The spacers are disposed in pure rolling contact at their ends with the internal cylindrical hoop surfaces of the extension members. Each of the spacers is positioned in pure rolling contact between a corresponding adjacent pair of the rolling members.

An aspect of the present disclosure is directed to a housing and rotatable shaft apparatus. The apparatus includes a static structure, a rotor assembly, and a bearing assembly. The bearing assembly includes a first static race coupled to the static structure, a first rotatable race coupled to the rotor assembly, a first rolling bearing element disposed in contact between the first static structure and the first rotatable race, a support member coupled to the first static race, a second static race disposed within and coupled to the support member, and a second rotatable race disposed within the support member. The second rolling bearing element is disposed between the second static race and the second rotatable race.