Vibration motor

Patent metadata

Field	Value
Publication number	US-12191748-B2
Application number	US-202218568807-A
Country	US
Kind code	B2
Filing date	Aug 5, 2022
Priority date	Aug 31, 2021
Publication date	Jan 7, 2025
Grant date	Jan 7, 2025

Abstract

A vibration motor is provided. The vibration motor comprises: a rotor shaft; a first magnet and a second magnet arranged on the rotor shaft so as to face each other; a circuit board having a hollow hole through which the rotor shaft passes and coils arranged thereon, the coils respectively facing the first and second magnets; a housing forming an inner space in which the rotor shaft and the circuit board are mounted; a shaft passing through the rotor shaft and fixedly erected in the housing; a first yoke and a second yoke on which the first and second magnets are respectively installed and which are fixedly coupled to the rotor shaft so as to integrally rotate along with the rotor shaft; a weight installed on the first yoke or the second yoke; and a bearing portion comprising a plurality of bearings coaxially arranged with the shaft.

First claim

What is claimed is:

1. A vibration motor, comprising:
a rotor shaft;
a first magnet and a second magnet arranged on the rotor shaft to face each other;
a circuit board, wherein the circuit board comprises a hollow hole, wherein the rotor shaft passes through the hollow hole, and coils arranged thereon, wherein the coils respectively face the first and second magnets;
a housing, wherein the housing forms an inner space, the rotor shaft and the circuit board are mounted in the inner space, to fix the circuit board;
a shaft passing through the rotor shaft and fixedly erected in the housing;
a first yoke and a second yoke, wherein the first and second magnets are respectively installed on the first yoke and the second yoke, and the first yoke and the second yoke are fixedly coupled to the rotor shaft to integrally rotate along with the rotor shaft;
a weight installed on the first yoke or the second yoke; and
a bearing portion, wherein the bearing portion comprises a plurality of bearings coaxially arranged with the shaft, at least one of the plurality of bearings is arranged to surround the shaft,
the rotor shaft is fitted with the plurality of bearings to rotate relative to the shaft, the rotor shaft comprises a cylindrical shape in close contact with outer rings of the plurality of bearings, and the rotor shaft comprises a diaphragm portion, wherein the diaphragm portion extends toward the shaft and is interposed between the plurality of bearings.

2. The vibration motor according to claim 1 , wherein the bearing portion comprises first and second bearings, the first and second bearings are arranged side by side in vertical direction and fixed to the shaft, and
wherein the rotor shaft is formed to be in close contact with outer rings of the first and second bearings, and the diaphragm portion is interposed between the first and second bearings.

3. The vibration motor according to claim 1 , wherein the housing has an insertion hole formed on one side, wherein an upper end of the shaft is inserted and fixed thereto.

4. The vibration motor according to claim 1 , wherein the housing has a pressing member formed on one side, wherein the pressing member protrudes downward to press an inner ring of a first bearing.

5. The vibration motor according to claim 1 , wherein the housing and the circuit board are closely fixed by ultrasonic welding.

6. The vibration motor according to claim 1 , wherein the housing is formed with a concave space, wherein the rotor shaft, second magnet and second yoke are accommodated therein, and the housing is provided with a support member in surface contact with at least a part of the circuit board outside the concave space to support the circuit board, and
wherein the support member is provided with at least one protrusion, wherein the at least one protrusion is formed to protrude upward, and the circuit board has a through-hole, wherein the through-hole is formed at a position corresponding to the at least one protrusion to allow the at least one protrusion to pass therethrough.

7. The vibration motor according to claim 1 , further comprising:
a bottom portion, wherein the bottom portion is formed in a shape of a plate, and placed and fixed to a lower case of the housing,
wherein the bottom portion is formed with a fixing member, wherein the fixing member protrudes upward at a predetermined height, wherein a lower end of the shaft is inserted and fixed therein.

8. The vibration motor according to claim 1 , wherein an upper case of the housing is provided with a first coupling portion, wherein the first coupling portion has a curved shape on at least a part of an outer edge,
wherein a lower case of the housing is provided with a second coupling portion, wherein the second coupling portion is formed in a shape corresponding to the first coupling portion to engage with the first coupling portion, and
wherein the first coupling portion and the second coupling portion are coupled to each other by ultrasonic welding.

9. The vibration motor according to claim 1 , wherein the shaft is fixed only to a lower case side of the housing,
wherein the rotor shaft comprises a rod portion, wherein the rod portion is disposed coaxially with the shaft and formed in a rod shape; and a cylindrical portion, wherein the cylindrical portion is disposed at a lower part of the rod portion and provided with a space inside where the shaft is located, and
wherein the bearing portion comprises a first bearing, an inner ring is fixed in the first bearing by being coupled to the rod portion and an outer ring is fixed in close contact with an upper case of the housing; and a second bearing, wherein an inner ring is fixed in the second bearing by being coupled to the shaft and an outer ring is in close contact with the cylindrical portion and fixed thereto.

Assignees

• Jahwa Electronics Co Ltd

Inventors

• Ryu Jong Soo
• Sung Hyun Gyu
• Jang Jung Hoon
• Lee Jun Ki

Classifications

• H02K2203/03

  Machines characterised by the wiring boards, i.e. printed circuit boards or similar structures for connecting the winding terminations · CPC title

• H02K21/24

  with magnets axially facing the armatures, e.g. hub-type cycle dynamos · CPC title

• H02K7/086

  radially supporting the rotor around a fixed spindle; radially supporting the rotor directly (H02K7/09 takes precedence) · CPC title

• H02K5/1737

  radially supporting the rotor around a fixed spindle; radially supporting the rotor directly · CPC title

• H02K3/26

  consisting of printed conductors · CPC title