CURRENT SENSOR

• US 20180321283A1
• Filed: 04/23/2018
• Published: 11/08/2018
• Est. Priority Date: 05/08/2017
• Status: Active Grant

• Current Assignee: Yazaki Corporation
• Original Assignee: Yazaki Corporation
• Inventors: SEI, Makoto, FUKUHARA, Toshiaki
• Granted Patent: US 10,634,702 B2
• Time in Patent Office: Days
• CPC Class Codes: G01R 1/18 Screening arrangements against electric or magnetic fields, e.g. against earth's field
• CPC Class Codes: G01R 15/202 using Hall-effect devices Hall elements in arrangements for measuring electrical power G01R21/08
• CPC Class Codes: G01R 15/207 Constructional details independent of the type of device used
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 3/00 Apparatus or processes specially adapted for the manufacture or maintenance of measuring instruments , e.g. of probe tips
• CPC Class Codes: H01F 3/14 Constrictions; Gaps, e.g. air-gaps in magnetic shunt paths H01F3/12

Abstract

A current sensor includes: a magnetic core member including a core main body obtained by forming a slit-shaped gap portion along a tube axis direction in a tube that surrounds a conductive member, which is an object to be energized, on an inner side with a clearance, the magnetic core member being configured to generate a magnetic flux corresponding to a current flowing through the conductive member; a magnetic sensor configured to output a signal corresponding to magnetic flux density in the gap portion; and a magnetic shield member including a shield main body that surrounds the core main body from an outer side of the core main body with a clearance, the magnetic shield member being configured to block magnetism between inside and outside of the shield main body by the shield main body.

Claims

1. A current sensor, comprising:

a magnetic core member including a core main body obtained by forming a slit-shaped gap portion along a tube axis direction in a tube that surrounds a conductive member, which is an object to be energized, on an inner side with a clearance, the magnetic core member being configured to generate a magnetic flux corresponding to a current flowing through the conductive member;

a magnetic sensor configured to output a signal corresponding to magnetic flux density in the gap portion; and

a magnetic shield member including a shield main body that surrounds the core main body from an outer side of the core main body with a clearance, the magnetic shield member being configured to block magnetism between inside and outside of the shield main body by the shield main body.

2. The current sensor according to claim 1, further comprising:

a sensor housing member housing the magnetic core member, the magnetic sensor, and the magnetic shield member, wherein

the sensor housing member includes;

a housing chamber housing the magnetic core member, the magnetic sensor, and the magnetic shield member; and

a positioning and holding mechanism holding the magnetic core member and the magnetic shield member with a clearance between the magnetic core member and the magnetic shield member.

3. The current sensor according to claim 2, wherein

the positioning and holding mechanism includes:

a core position regulating portion configured to regulate a relative position of the magnetic core member in the housing chamber from an inner side of the magnetic core member;

shield holding portions sandwiching the magnetic shield member from an outer side of the magnetic shield member in order to fix a relative position of the magnetic shield member in the housing chamber; and

a shield position regulating portion configured to regulate the relative position of the magnetic shield member in the housing chamber in a direction intersecting a sandwiching direction of the shield holding portions.

4. The current sensor according to claim 1, wherein

in an alternate current circuit including a plurality of the conductive members, a combination of the magnetic core member, the magnetic sensor, and the magnetic shield member is provided for each of the conductive members.

5. The current sensor according to claim 2, wherein

in an alternate current circuit including a plurality of the conductive members, a combination of the magnetic core member, the magnetic sensor, and the magnetic shield member is provided for each of the conductive members.

6. The current sensor according to claim 3, wherein

in an alternate current circuit including a plurality of the conductive members, a combination of the magnetic core member, the magnetic sensor, and the magnetic shield member is provided for each of the conductive members.

7. The current sensor according to claim 1, wherein

the magnetic sensor is a Hall IC including a Hall element as a magnetic detection element.

8. The current sensor according to claim 2, wherein

the magnetic sensor is a Hall IC including a Hall element as a magnetic detection element.

9. The current sensor according to claim 3, wherein

the magnetic sensor is a Hall IC including a Hall element as a magnetic detection element.

10. The current sensor according to claim 4, wherein

the magnetic sensor is a Hall IC including a Hall element as a magnetic detection element.

11. The current sensor according to claim 5, wherein

the magnetic sensor is a Hall IC including a Hall element as a magnetic detection element.

12. The current sensor according to claim 6, wherein

the magnetic sensor is a Hall IC including a Hall element as a magnetic detection element.