US-12627193-B2 - Motor

US12627193B2US 12627193 B2US12627193 B2US 12627193B2US-12627193-B2

Abstract

A motor is provided that includes a shaft, a rotor coupled to the shaft, a stator disposed to correspond to the rotor, a bearing housing coupled to the shaft, and a bearing that supports the bearing housing. The rotor includes a rotor core and a magnet coupled to the rotor core. The bearing housing includes a first surface in contact with the bearing, a second surface in contact with the rotor core, and a third surface in contact with the shaft.

Inventors

Ju Hwan KU
Jae Young Kim

Assignees

LG INNOTEK CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20220413
Priority Date: 20210413

Claims (10)

1 . A motor comprising: a shaft; a rotor coupled to the shaft; a stator disposed to correspond to the rotor; a bearing housing coupled to the shaft; and a bearing which supports the bearing housing, wherein the rotor includes a rotor core and a magnet coupled to the rotor core, and the bearing housing includes a first surface in contact with the bearing, a second surface in contact with the rotor core, and a third surface in contact with the shaft, wherein the bearing housing includes an insertion region inserted between the shaft and the rotor core, and the insertion region overlaps the shaft in an axial direction and does not overlap the bearing in a direction perpendicular to the axial direction.
2 . The motor of claim 1 , wherein: the shaft includes a first region having a first outer diameter and a second region having a second outer diameter smaller than the first outer diameter, and the bearing housing includes an end portion disposed between the second region of the rotor core and the second region of the shaft.
3 . The motor of claim 2 , wherein: an inner diameter of the end portion of the bearing housing is equal to the second outer diameter of the shaft; and an outer diameter of the end portion of the bearing housing is equal to the second inner diameter of the rotor core.
4 . The motor of claim 2 , wherein the bearing housing includes a step region which extends from the end portion and has an outer diameter equal to an outer diameter of the end portion and an inner diameter smaller than an inner diameter of the end portion.
5 . The motor of claim 1 , wherein the stator includes a coil, wherein the bearing housing is disposed between the rotor core and the shaft, and wherein the bearing is disposed between the bearing housing and the coil.
6 . The motor of claim 5 , wherein a part of the coil and a part of the bearing overlap in a direction perpendicular to the axial direction.
7 . The motor of claim 1 , wherein the bearing housing includes a first surface in contact with the bearing, a second surface in contact with the rotor core, and a third surface in contact with the shaft, wherein the bearing housing includes an insertion region inserted between the shaft and the rotor core, and wherein the insertion region overlaps the shaft in an axial direction and does not overlap the bearing in a direction perpendicular to the axial direction.
8 . The motor of claim 7 , wherein: the first surface and the second surface are an outer surface of the bearing housing; and the third surface is an inner surface of the bearing housing.
9 . The motor of claim 7 , wherein the entire insertion region does not overlap the bearing in a direction perpendicular to the axial direction.
10 . The motor of claim 7 , wherein the rotor core includes a stopper which limits an insertion depth of the insertion region.

Description

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS This application is a U.S. National Stage Application under 35 U.S.C. § 371 of PCT Application No. PCT/KR2022/005365, filed Apr. 13, 2022, which claims priority to Korean Patent Application No. 10-2021-0047810, filed Apr. 13, 2021, whose entire disclosures are hereby incorporated by reference. TECHNICAL FIELD The present invention relates to a motor. BACKGROUND ART A motor includes a shaft, a rotor, and a stator. The rotor and the stator are accommodated in a housing. The stator may include a stator core and a coil wound around the stator core. The shaft may be a hollow member. Bearings which support the shaft may support one side and the other side of the shaft. In this case, one side of the shaft may be coupled to a bearing housing, and the bearings may support the bearing housing. Since one side of the shaft is coupled to the bearing housing, there is a problem of a limitation in reducing the size of the motor in an axial direction. DISCLOSURE Technical Problem Accordingly, the present invention is directed to providing a motor of which a size is reduced in an axial direction. Technical Solution One aspect of the present invention provides a motor including a shaft, a rotor coupled to the shaft, a stator disposed to correspond to the rotor, a bearing housing coupled to the shaft, and a bearing which supports the bearing housing, wherein the rotor includes a rotor core and a magnet coupled to the rotor core, and the bearing housing includes a first surface in contact with the bearing, a second surface in contact with the rotor core, and a third surface in contact with the shaft. Another aspect of the present invention provides a motor including a shaft, a rotor coupled to the shaft, a stator disposed to correspond to the rotor, a bearing housing coupled to the shaft, and a bearing which supports the bearing housing, wherein the rotor includes a rotor core and a magnet coupled to the rotor core, the rotor core includes a first region having a first inner diameter and a second region having a second inner diameter greater than the first inner diameter, the shaft includes a first region having a first outer diameter and a second region having a second outer diameter smaller than the first outer diameter, and the bearing housing includes an end portion disposed between the second region of the rotor core and the second region of the shaft. Still another aspect of the present invention provides a motor including a shaft, a rotor coupled to the shaft, a stator disposed to correspond to the rotor, a bearing housing coupled to the shaft, and a bearing which supports the bearing housing, wherein the rotor includes a rotor core and a magnet coupled to the rotor core, the bearing housing includes an insertion region inserted between the shaft and the rotor core, and the insertion region overlaps the shaft in an axial direction and does not overlap the bearing in a direction perpendicular to the axial direction. Yet another aspect of the present invention provides a motor including a shaft, a rotor coupled to the shaft, a stator which is disposed to correspond to the rotor and includes a coil, a bearing housing coupled to the shaft, and a bearing which supports the bearing housing, wherein the rotor includes a rotor core and a magnet coupled to the rotor core, the bearing housing is disposed between the rotor core and the shaft, and the bearing is disposed between the bearing housing and the coil. Advantageous Effects According to an embodiment, since a part of a bearing housing is positioned inside a rotor core, there is an advantage of reducing a size of a motor in an axial direction. According to an embodiment, since a bearing housing is in contact with a stopper disposed on an inner circumferential surface of a rotor core, there is an advantage of precisely setting a position of the rotor core in an axial direction when the rotor core and a shaft are assembled. According to an embodiment, an outer surface of a bearing housing is used as a region which is fitted to a rotor core and supports a bearing, and an inner surface of the bearing housing is used as a structure which supports a spindle of an external device. DESCRIPTION OF DRAWINGS FIG. 1 is a view illustrating a motor according to an embodiment. FIG. 2 is a view illustrating a shaft illustrated in FIG. 1. FIG. 3 is a side cross-sectional view illustrating the shaft along line A-A of FIG. 2. FIG. 4 is a view illustrating a rotor core illustrated in FIG. 1. FIG. 5 is a side cross-sectional view illustrating the shaft along line B-B of FIG. 4. FIG. 6 is a view illustrating a bearing housing. FIG. 7 is a side cross-sectional view illustrating the bearing housing along line C-C of FIG. 6. FIG. 8(a) to (c) are a set of views illustrating an assembly process of the shaft and a rotor. FIG. 9 is a side cross-sectional view illustrating a portion around the bearing housing of the motor. FIG. 10 is an enlarged view illust