公开(公告)号：US20210040990A1

公开(公告)日：2021-02-11

申请号：US16767285

申请日：2018-12-07

Applicant: NTN CORPORATION

Inventor： Kazuyoshi HARADA ,  Shinji KOMATSUBARA ,  Shouhei OKA ,  Jun HIRADE

IPC: F16C33/74 ,  F16C17/08 ,  F16C17/02

Abstract: A fluid dynamic bearing device 1 includes: a shaft member 2; a bearing sleeve 8 that has the shaft member 2 inserted into the inner periphery thereof; a housing 7 that holds the bearing sleeve 8 on the inner periphery thereof and has a bottomed cylindrical shape having an opening at an end portion on one axial side; and a seal member 9 provided at the opening of the housing 7. The seal member 9 has a disk portion 9a disposed on one axial side of the bearing sleeve 8, and a protrusion (cylindrical portion 9b) protruding to the other axial side from an outer diameter end of the disk portion 9a. An outer peripheral surface 9c of the seal member 9 is fixed to an inner peripheral surface 7a1 of the housing 7.

公开(公告)号：US20200016650A1

公开(公告)日：2020-01-16

申请号：US16335283

申请日：2017-08-31

Applicant: NTN CORPORATION

Inventor： Jun HIRADE ,  Masashi YAMAGOU ,  Mikihisa FUJIWARA ,  Tetsuya KURIMURA

IPC: B21K1/06 ,  B23B1/00

Abstract: A shaft member for a fluid bearing device includes, on an outer peripheral surface thereof, two bearing surfaces (31 and 32) separated from each other in an axial direction, and a middle relief portion (33) formed between the bearing surfaces (31 and 32) and having a diameter smaller than a diameter of the bearing surfaces. The middle relief portion (33) includes a cylindrical surface portion (331) having a ground surface, and stepped portions (332) arranged on both axial sides of the cylindrical surface portion and having a diameter difference from the cylindrical surface portion.

公开(公告)号：US20180178343A1

公开(公告)日：2018-06-28

申请号：US15903556

申请日：2018-02-23

Applicant: NTN CORPORATION

Inventor： Jun HIRADE ,  Shuichi KOMATSU

IPC: B24B5/307 ,  F16C3/02 ,  F16C17/10 ,  B24B5/04 ,  F16C33/14

CPC classification number: B24B5/307 ,  B24B5/04 ,  F16C3/02 ,  F16C17/107 ,  F16C33/14 ,  F16C2220/70 ,  F16C2226/10

Abstract: Grinding is performed on an outer peripheral surface of a shaft member while rotationally driving the shaft member under a state in which both end surfaces of the shaft member are sandwiched between a pair of support portions. A convex surface is formed on one axial end surface of the shaft member or an end surface of one of the pair of support portions, and a flat surface is formed on the other of the one axial end surface of the shaft member and the end surface of the one of the pair of support portions. The flat surface and an apex of the convex surface are brought into contact with each other to support one axial end portion of the shaft member.