Apparatus and method for sensing electric current based on electric signal from magneto-electric conversion element

• US 6,441,604 B1
• Filed: 08/21/2000
• Issued: 08/27/2002
• Est. Priority Date: 08/20/1999
• Status: Active Grant

• Current Assignee: Yazaki Corporation
• Original Assignee: Yazaki Corporation
• Inventors: Morimoto, Mitsuaki, Gohara, Takashi, Tamai, Yasuhiro, Ikuta, Yoshinori
• Primary Examiner(s): Le, N.
• Assistant Examiner(s): Nguyen, Vincent Q.
• Application Number:
  US09/642,098
• Time in Patent Office: 736 Days
• Field of Search: 324/117.H, 324/117.R, 324/251, 324/127, 324/235, 324/225, 324/207.13, 324/207.12
• US Class Current: 324/117.00R
• CPC Class Codes: G01R 15/202 using Hall-effect devices Hall elements in arrangements for measuring electrical power G01R21/08

Abstract

An electric current sensor for sensing an electric current flowing through a conductor comprises a single hall element having a magnetic-flux sensitive surface, and an angle adjusting mechanism. The angle adjusting mechanism changes an angle between the magnetic-flux sensitive surface and the direction of a magnetic flux induced by the electric current flowing through the conductor. The magneto-electric conversion element outputs an electric signal in response to a magnetic flux density at the magnetic-flux sensitive surface. The electric current sensor detects the electric current flowing through the conductor based on the electric signal output from the magneto-electric conversion element whose magnetic-flux sensitive surface is oriented with respect to the magnetic flux at a selected angle.

Claims

1. An electric current sensor for sensing an electric current flowing through a conductor, the electric current inducing magnetic flux about the conductor, the sensor comprising:

a magneto-electric conversion element having a magnetic-flux sensitive surface and being configured to output an electric signal relative to a magnetic flux density at the magnetic-flux sensitive surface;

a junction box for accommodating a portion of the conductor and having a hole on one face; and

an angle adjusting mechanism for changing an angle between the magnetic-flux sensitive surface and the direction of the magnetic flux, the angle adjusting mechanism including a cock for supporting the magneto-electric conversion element and configured to fit into the hole of the junction box, the cock being rotatable with respect tot he hole of the junction box, wherein the electric current sensor detects the electric current flowing through the conductor based on the electric signal output from the magneto-electric conversion element whose magnetic-flux sensitive surface is oriented with respect to the magnetic flux at a selected angle.

2. The electric current sensor according to claim 1, wherein:

the hole has a plurality of recesses around its circumference at a predetermined interval, and the cock has a plurality of teeth along its periphery at a predetermined interval; and

the angle adjusting mechanism comprises the teeth of the cock and the recesses of the hole which are meshed with and disengaged from each other.

3. The electric current sensor according to claim 1, wherein:

the hole has an internal thread, and the cock has an external thread; and

the angle adjusting mechanism comprises the external thread of the cock and the internal thread of the hole.

6. The electric current sensor according to claim 1, further comprising a clipping frame having a slit and two wings separated by the slit, the conductor being inserted in the slit and pinched by the two wings, wherein the magneto-electric conversion element is a pair of hall elements placed inside the respective wings of the clipping frame, each hall element having a magnetic-flux sensitive surface.

7. The electric current sensor according to claim 6, wherein:

a pair of angle-adjusting projections are formed in the inner faces of the slit, and a plurality of angle-adjusting holes are formed in the conductor at a predetermined interval along an arch, the pair of angle-adjusting projections being fit into one of the angle-adjusting holes; and

the pair of angle-adjusting projections and the plurality of holes constitute the angle adjusting mechanism.

8. The electric current sensor according to claim 6, wherein:

a pair of angle-adjusting recesses are formed in the inner faces of the slit, and a plurality of angle-adjusting projections are formed on the conductor at a predetermined interval along an arch, one of the angle-adjusting projections being fit into the angle-adjusting recesses; and

the pair of angle-adjusting recesses and the plurality of angle-adjusting projections constitute the angle adjusting mechanism.

4. An electric current sensor for sensing an electric current flowing through a conductor, the electric current inducing magnetic flux about the conductor, the sensor comprising:

a magneto-electric conversion element having a magnetic-flux sensitive surface and being configured to output an electric signal relative to a magnetic flux density at the magnetic-flux sensitive surface;

an angle adjusting mechanism for changing an angle between the magnetic-flux sensitive surface and the direction of the magnetic flux, wherein the electric current sensor measures the electric current flowing through the conductor based on the electric signal output from the magneto-electric conversion element whose magnetic-flux sensitive surface is oriented with respect to the magnetic flux at a selected angle.

5. The electric current sensor according to claim 4, further comprising a cock for supporting the magneto-electric conversion element, wherein:

a portion of the cock functions as a part of the angle adjusting mechanism; and

the magneto-electric conversion element is supported by the cock so that the magnetic-flux sensitive surface is oriented at a predetermined angle with respect to the direction of the magnetic flux induced by the electric current flowing through the conductor.

9. A method for sensing an electric current flowing through a conductor, the electric current inducing magnetic flux about the conductor, the method comprising the steps of:

placing a magneto-electric conversion element in the magnetic flux, the magneto-electric conversion element having a magnetic-flux sensitive surface;

adjusting the orientation of the magnetic-flux sensitive surface with respect to the direction of the magnetic flux;

causing the magneto-electric conversion element to output an electric signal relative to a magnetic flux density sensed at the magnetic-flux sensitive surface; and

measuring the electric current flowing through the conductor based on the electric signal output generated from the magneto-electric conversion element.