公开(公告)号：US20180051791A1

公开(公告)日：2018-02-22

申请号：US15660347

申请日：2017-07-26

Applicant: Johnson Electric S.A.

Inventor： Jing Ning TA ,  Lap Wah LO ,  Xing Ju YI ,  Qiu Mei LI

IPC: F16H55/17 ,  F16H57/08 ,  F16H1/28

CPC classification number: F16H55/17 ,  F16H1/28 ,  F16H1/46 ,  F16H57/08 ,  F16H2055/176

Abstract: The present invention relates to a ring gear and a gear reduction device. The ring gear includes an annular body with a plurality of mounting portions, and a plurality of teeth arranged on an inner circumferential surface of the annular body. The annular body and the teeth are integrally formed from powder metal, and the mounting portions and the teeth are at least partly overlapped in an axial direction of the annular body. The mounting portions are integrally formed with the annular body and the teeth, which results in concentricity between the mounting portion and the teeth being improved and cost of the ring gear being reduced. Furthermore, the mounting portions are overlapped with the teeth, which reduces the axial size of the ring gear.

公开(公告)号：US20180051777A1

公开(公告)日：2018-02-22

申请号：US15660321

申请日：2017-07-26

Applicant: Johnson Electric S.A.

Inventor： Jing Ning TA ,  Lap Wah LO ,  Xing Ju YI ,  Qiu Mei LI

IPC: F16H1/46 ,  F16H55/17 ,  F16H57/08 ,  B22F5/08 ,  B22F3/03

CPC classification number: F16H1/46 ,  B21J5/025 ,  B21K1/30 ,  B21K1/305 ,  B22F3/03 ,  B22F5/08 ,  F16H55/17 ,  F16H57/08 ,  F16H2055/176

Abstract: The present invention provides a ring gear and a gear reduction device. The ring gear includes a one-piece annular body made from powder metallurgy material, and a first ring gear part and a second ring gear part formed on a surface of the annular body. The first ring gear part and the second ring gear part are arranged along an axial direction of the annular body. The ring gear has a density less than 92% of its theoretical density and a mass of 6.0 to 8.0 grams per cubic millimeter. The present invention further provides a mold for manufacturing the ring gear. The ring gear of the present invention includes two ring gears integrally formed at once, and the two ring gears have improved concentricity.