STEPPING MOTOR AND SYSTEM THEREOF

• US 20150077033A1
• Filed: 05/30/2014
• Published: 03/19/2015
• Est. Priority Date: 09/17/2013
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Kun-woo, Shim, Jae-kyu, Cho, Woo-jong, Koo, Bon-min
• Granted Patent: US 9,293,976 B2
• Time in Patent Office: Days
• US Class Current: 318/696
• CPC Class Codes: H02K 11/215 Magnetic effect devices, e.g. Hall-effect or magneto-resistive elements
• CPC Class Codes: H02K 37/00 Motors with rotor rotating step by step and without interrupter or commutator driven by the rotor, e.g. stepping motors
• CPC Class Codes: H02K 37/14 with magnets rotating within the armatures
• CPC Class Codes: H02P 8/38 the fault being step-out

Abstract

A stepping motor includes a housing, a stator assembly, a rotor, and a sensor portion. The stator assembly is disposed inside the housing. The rotor is rotatably disposed inside the stator assembly and includes a rotation shaft, and opposite ends of the rotation shaft are supported by the housing. The sensor portion is disposed inside the housing and detects a magnetic field of the rotor.

Claims

1. A stepping motor comprising:

a housing;

a stator assembly disposed inside the housing;

a rotor that is rotatably disposed inside the stator assembly and includes a rotation shaft, and opposite ends of the rotation shaft are supported by the housing; and

a sensor portion that is disposed inside the housing and detects a magnetic field of the rotor.

2. The stepping motor of claim 1, wherein the sensor portion comprises a magneto resistive sensor.

3. The stepping motor of claim 2, wherein the magneto resistive sensor is disposed above a top end of the rotor.

4. The stepping motor of claim 3, wherein the magneto resistive sensor is disposed at a position that is spaced apart from the top end of the rotor, and the position is at an intersection of a center line of an upper pole piece of an upper yoke of the stator assembly, a straight line passing through a center of the rotor, and a tangent line of an outer diameter of the rotor.

5. The stepping motor of claim 2, wherein:

the rotor comprises an upper rotor disposed on the rotation shaft and a lower rotor that is spaced apart from the upper rotor and is disposed on the rotation shaft coaxially with the upper rotor; and

the magneto resistive sensor is disposed in a space between the upper rotor and the lower rotor.

6. The stepping motor of claim 1, wherein the sensor portion comprises two magneto resistive sensors that are arranged with a 90 degree phase difference.

7. The stepping motor of claim 2, wherein the sensor portion further comprises a support portion to support the magneto resistive sensor.

8. The stepping motor of claim 1, wherein the sensor portion comprises a Hall sensor.

9. The stepping motor of claim 1, wherein the sensor portion comprises a flexible printed circuit board that is arranged to be spaced apart from an outer circumferential surface of the rotor and to surround the rotor, and the flexible printed circuit board has formed thereon a frequency generating pattern.

10. The stepping motor of claim 1, wherein the sensor portion comprises a disc-like printed circuit board that is arranged to be spaced apart from a top end of the rotor, and the printed circuit board has formed thereon a frequency generating pattern.

11. A stepping motor system comprising:

a stepping motor, wherein the stepping motor comprises;

a housing;

a stator assembly disposed inside the housing;

a rotor that is rotatably disposed inside the stator assembly and includes a rotation shaft, and opposite ends of the rotation shaft are supported by the housing; and

a sensor portion that is disposed inside the housing and detects a magnetic field of the rotor; and

a controller configured to control the stepping motor, wherein the controller comprises;

a step-out determination unit configured to determine whether a step-out phenomenon of the stepping motor has occurred by receiving a signal from the sensor portion; and

a driving unit configured to drive the stepping motor.

12. The stepping motor system of claim 11, wherein when the step-out determination unit detects a step-out phenomenon of the stepping motor, the controller controls the driving unit to increase a driving force of the stepping motor.

13. The stepping motor system of claim 11, wherein the sensor portion comprises a magneto resistive sensor or a Hall sensor.

14. The stepping motor system of claim 13, wherein the magneto resistive sensor is disposed above the rotor.

15. The stepping motor system of claim 14, wherein the magneto resistive sensor is disposed at a position that is spaced apart from a top end of the rotor, and the position is at an intersection of a center line of an upper pole piece of an upper yoke of the stator assembly, a straight line passing through a center of the rotor, and a tangent line of an outer diameter of the rotor.

16. The stepping motor system of claim 13, wherein:

the rotor comprises an upper rotor disposed on the rotation shaft and a lower rotor that is spaced apart from the upper rotor and is disposed on the rotation shaft coaxially with the upper rotor, and

the magneto resistive sensor is disposed in a space between the upper rotor and the lower rotor.

17. The stepping motor system of claim 11, wherein the sensor portion comprises two magneto resistive sensors that are arranged with a 90 degree phase difference.

18. The stepping motor system of claim 13, wherein the sensor portion further comprises a support portion to support the magneto resistive sensor.

19. The stepping motor system of claim 11, wherein the sensor portion comprises a flexible printed circuit board that is arranged to be spaced apart from an outer circumferential surface of the rotor and to surround the rotor, and the flexible printed circuit board has formed thereon a frequency generating pattern.

20. The stepping motor system of claim 11, wherein the sensor portion comprises a disc-like printed circuit board that is arranged to be spaced apart from a top end of the rotor, the printed circuit board has formed thereon which a frequency generating pattern.