公开(公告)号：US20180320737A1

公开(公告)日：2018-11-08

申请号：US15771892

申请日：2016-10-12

申请人： NTN CORPORATION

发明人： Michio HORI ,  Hideto TORISAWA ,  Hiroshi YUKI ,  Chikara OHKI ,  Kazuhiro YAGITA

IPC分类号： F16C19/38 ,  F16C33/62 ,  F16C33/64 ,  F16C43/04 ,  C21D1/10 ,  C21D1/28 ,  C22C38/22 ,  C22C38/44 ,  C21D9/40 ,  C21D7/06

CPC分类号： F16C19/385 ,  C21D1/10 ,  C21D1/28 ,  C21D7/06 ,  C21D9/40 ,  C22C38/00 ,  C22C38/22 ,  C22C38/44 ,  F03D80/70 ,  F05B2240/50 ,  F16C19/38 ,  F16C33/62 ,  F16C33/64 ,  F16C43/04 ,  F16C2360/31 ,  Y02P10/253

摘要： A method for producing a bearing ring of a double row tapered roller bearing includes the steps of: preparing a formed body; forming a heated region; cooing; and removing. In the step of forming a heated region, an induction heating coil arranged to face part of the groove and induction-heating the fixated body is relatively rotated along the circumferential direction of the groove to form a heated region including the bottom surface of the groove and heated to a temperature of at least an Al point. In the cooling step, the whole of the heated region is simultaneously cooled to a temperature of not more than an Ms point. After the step of forming a heated region before the step of cooling, the method further includes the step of retaining the formed body in a state where heating is stopped.

公开(公告)号：US20180347623A1

公开(公告)日：2018-12-06

申请号：US15771763

申请日：2016-10-12

申请人： NTN CORPORATION

发明人： Michio HORI ,  Hideto TORISAWA ,  Hiroshi YUKI ,  Chikara OHKI ,  Kazuhiro YAGITA

IPC分类号： F16C19/38 ,  C21D9/40 ,  C21D1/42 ,  C21D6/00 ,  C22C38/22 ,  C22C38/04 ,  C22C38/02 ,  C21D1/10 ,  C21D1/28 ,  F16C33/62 ,  F16C33/64

摘要： There is prepared a formed body constituted of steel and having an outer circumferential surface having an annular groove having a bottom surface to serve as a raceway surface of the bearing ring. In the step of forming a heated region, the formed body is induction heated to form a heated region including the bottom surface of the groove and heated to a temperature of at least an A1 point. In the cooling step, the whole of the heated region is simultaneously cooled to a temperature of not more than an Ms point. The step of retaining the formed body in a state in which heating is stopped is performed after the step of forming a heated region before the step of cooling. In the step of retaining, dispersion in temperature in the heated region in the circumferential direction is suppressed to not more than 20° C.

公开(公告)号：US20180347005A1

公开(公告)日：2018-12-06

申请号：US15771723

申请日：2016-10-12

申请人： NTN CORPORATION

发明人： Michio HORI ,  Hideto TORISAWA ,  Hiroshi YUKI ,  Chikara OHKI ,  Kazuhiro YAGITA

IPC分类号： C21D9/40 ,  C21D1/10 ,  F16C19/38 ,  F16C33/64

CPC分类号： C21D9/40 ,  C21D1/10 ,  C21D1/18 ,  C21D2221/00 ,  C21D2221/01 ,  C21D2221/02 ,  C21D2221/10 ,  F16C19/38 ,  F16C19/385 ,  F16C19/386 ,  F16C33/526 ,  F16C33/58 ,  F16C33/583 ,  F16C33/585 ,  F16C33/605 ,  F16C33/64 ,  F16C43/04 ,  F16C2223/18 ,  F16C2240/30 ,  F16C2360/31 ,  Y02P10/253 ,  Y10T29/49684

摘要： A double row tapered roller bearing includes: an outer ring having an annular shape; an inner ring disposed on an inner circumferential side of the outer ring and having an annular shape; and rollers. The inner ring has an outer circumferential surface facing the outer ring and having two rows of grooves having a bottom surface serving as a raceway surface. The rollers are tapered rollers disposed in the grooves in contact with the raceway surface of the inner ring and are also in contact with the outer ring. At outer circumferential surface of the inner ring, a region adjacent to the groove includes a hardened region extending from the inner peripheral surface of the groove to the region adjacent to the groove, and an unhardened region located at a position farther from the groove than the hardened region and being smaller in hardness than the hardened region.