公开(公告)号：US20180320737A1

公开(公告)日：2018-11-08

申请号：US15771892

申请日：2016-10-12

Applicant: NTN CORPORATION

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

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

CPC classification number: 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

Abstract: 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：US20160153496A1

公开(公告)日：2016-06-02

申请号：US15016906

申请日：2016-02-05

Applicant: NTN CORPORATION

Inventor： Hiroshi YUKI ,  Chikara OHKI ,  Kazuhiro YAGITA

IPC: F16C33/64 ,  C21D1/42 ,  C22C38/02 ,  C22C38/22 ,  C22C38/04 ,  C21D1/10 ,  C21D9/40

CPC classification number: F16C33/64 ,  C21D1/10 ,  C21D1/42 ,  C21D9/40 ,  C21D2211/008 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/22 ,  C22C38/44 ,  F16C19/38 ,  F16C19/386 ,  F16C23/086 ,  F16C2240/18 ,  F16C2300/14 ,  F16C2360/31 ,  Y02P10/253

Abstract: Disclosed is a method for heat-treating a ring-shaped member, which makes it possible to form a quench-hardened region having a uniform annular shape in the circumferential direction, while the production costs in terms of the quenching apparatus are kept down. The method includes the following steps: a step in which a coil which is disposed in such a way as to face a rolling contact surface of a ring-shaped formed body made of steel and which performs induction heating of the formed body is rotated relative to the formed body in the circumferential direction thereof, whereby an annular heating region which is heated to a temperature at or above an A1 point is formed on the formed body; and a step in which the whole of the heating region is simultaneously cooled to a temperature at or below an MS point.

Abstract translation: 公开了一种用于对环形构件进行热处理的方法，这使得可以在圆周方向上形成具有均匀环形形状的淬火硬化区域，同时使淬火装置的生产成本降低。 该方法包括以下步骤：将由钢制成的环状成形体的滚动面的面向与成形体进行感应加热相对应地设置的线圈相对于 成形体在其周向上，由此在被成形体上形成被加热到等于或高于A1点的温度的环形加热区域; 并且将整个加热区域同时冷却至等于或低于MS点的温度的步骤。

公开(公告)号：US20190338808A1

公开(公告)日：2019-11-07

申请号：US16474525

申请日：2017-12-05

Applicant: NTN Corporation

Inventor： Hiroshi YUKI ,  Miyu SATO ,  Chikara OHKI

IPC: F16C33/64 ,  F16C33/58 ,  F16C33/62 ,  C21D9/40 ,  C21D6/00 ,  C22C38/44 ,  C22C38/42 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00

Abstract: In one aspect of the present invention, a method for manufacturing a bearing component includes: a preparation step of preparing a ring-shaped member of steel having a radially inner surface, a radially outer surface, and a thickness which is a distance between the radially inner surface and the radially outer surface; and a heat treatment step of performing a heat treatment to locally heat one of the radially inner surface and the radially outer surface to a heat treatment temperature and subsequently cool the one of the radially inner surface and the radially outer surface, the method satisfying S≥930/(0.3477 W2−1.594 W−0.804), where S represents an average temperature increasing rate (unit: ° C./sec) applied when the surface is heated and W represents the thickness (unit: mm).

公开(公告)号：US20180347623A1

公开(公告)日：2018-12-06

申请号：US15771763

申请日：2016-10-12

Applicant: NTN CORPORATION

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

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

Abstract: 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

Applicant: NTN CORPORATION

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

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

CPC classification number: 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

Abstract: 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.