BALL SCREW DEVICE AND DOUBLE-ROW BEARING DEVICE

• Main Author: TOMIKAWA TAKASHI
• Format: Patent
• Language: English; Japanese
• Published: 31.10.2019
• Subjects: BEARINGS; BLASTING; ELEMENTS OR CRANKSHAFT MECHANISMS; ENGINEERING ELEMENTS AND UNITS; FLEXIBLE SHAFTS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MECHANICAL ENGINEERING; ROTARY BODIES OTHER THAN GEARING ELEMENTS; SHAFTS; THERMAL INSULATION IN GENERAL; WEAPONS

To provide a ball screw device which can reduce a pressing force necessary for imparting a sufficient preload to a double-row bearing device irrespective of a dimension of the double-row bearing device, and the double-row bearing device.SOLUTION: A double-row bearing device 10 comprises: an outer ring 120; a first inner ring main body 131 which is arranged at a cylinder part 82 so as to be integrally rotatable to an external peripheral face of the cylinder part 82; a second inner ring main body 141 fit to the external peripheral face of the cylinder part 82 with an interval between the first inner ring main body 131 and itself in an axial line direction; and a portion being at least either of a first region protruding toward the second inner ring main body 141 from a first end face 136 of the first inner ring main body 131 opposing the second inner ring main body 141, and a first region protruding toward the first inner ring main body 131 from a second end face 146 of the second inner ring main body 141 opposing the first inner ring main body 131, and small in a projection area smaller than the first end face 136 and the second end face 146 when viewed from the axial line direction.SELECTED DRAWING: Figure 3 【課題】複列軸受装置の寸法に関わらず、複列軸受装置に十分な予圧を付与する際に必要とされる押付力を小さくすることができるボールねじ装置及び複列軸受装置を提供すること。【解決手段】複列軸受装置１０は、外輪１２０と、筒部８２の外周面に対して筒部８２と一体回転可能に設けられる第一内輪本体１３１と、軸線方向において第一内輪本体１３１との間に隙間を隔てた状態で筒部８２の外周面に嵌合される第二内輪本体１４１と、第一内輪本体１３１の第二内輪本体１４１と対向する第一端面１３６から第二内輪本体１４１へ向けて突出する第一部位、及び、第二内輪本体１４１の第一内輪本体１３１と対向する第二端面１４６から第一内輪本体１３１へ向けて突出する第一部位の少なくとも一方であって、第一端面１３６及び第二端面１４６よりも軸線方向から見た投影面積が小さい凸部とを備える。【選択図】図３