Hall-effect sensor with integrally molded frame, magnet, flux guide and insulative film

• US 5,196,794 A
• Filed: 04/08/1991
• Issued: 03/23/1993
• Est. Priority Date: 03/14/1989
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Murata, Shigemi
• Primary Examiner(s): Strecker, Gerard R.
• Application Number:
  US07/681,307
• Time in Patent Office: 715 Days
• Field of Search: 324/173, 324/174, 324/207.2, 324/207.21, 324/207.25, 324/235, 324/251, 324/252, 338/32 H, 323/368, 310/70 R, 310/DIG. 3, 123/146.5 A, 123/617, 174/52.2
• US Class Current: 324/251
• CPC Class Codes: F02P 7/07 Hall-effect pick-up devices
• CPC Class Codes: G01D 5/147 influenced by the movement of a third element, the position of Hall device and the source of magnetic field being fixed in respect to each other
• CPC Class Codes: G01P 3/488 delivered by variable reluctance detectors
• CPC Class Codes: H03K 17/9505 Constructional details
• CPC Class Codes: H03K 17/9517 using galvanomagnetic devices

Abstract

A Hall-effect sensor, wherein a Hall element is disposed in a magnetic path being formed by a magnet and a flux guide, and the magnet, flux guide, and Hall element are integrally held with a molded frame, and the Hall element is fixed to the magnet (or flux guide) or the molded frame. This Hall-effect sensor can easily position the Hall element with higher sensitivity.

Claims

1. A Hall-effect sensor, comprising:

flux generating means for generating a magnetic flux, wherein said flux generating means includes a magnet for generating magnetic flux, a first flux guide disposed in contact with said magnet, and a second flux guide arranged in a position to face said magnet and said first flux guide with a gap therebetween;

a Hall element disposed in the path of said magnetic flux, and wherein said Hall element is fixed to one of said magnet and said second flux guide;

holding means for holding said flux generating means and said Hall element integrally therewith, said holding means comprising a molded frame;

a peripheral circuit provided with said Hall element such that said peripheral circuit is commonly mounted with said Hall element; and

an insulative film formed integrally on said magnet or said second flux guide,

wherein said Hall element is fixed to said magnet or said second flux guide with said insulative film therebetween, said molded frame completely encapsulating said Hall element, said flux generating means, and said peripheral circuit to fixedly position said Hall element, said flux generating means, and said peripheral circuit relative to each other.

2. A Hall-effect sensor as set forth in claim 1, further comprising:

a printed conductor formed on said insulative film, and

connecting means for electrically connecting said Hall element to said printed conductor.

3. A Hall-effect sensor as set forth in claim 2, wherein said connecting means is solder.

4. A Hall-effect sensor as set forth in claim 1, wherein said first and second flux guides are adapted to transmit the generated magnetic flux.

5. A Hall-effect sensor as set forth in claim 1, wherein said Hall element is a bare Hall chip.

6. A Hall-effect sensor as set forth in claim 5, wherein said Hall chip is a Hall IC.

7. A Hall-effect sensor, comprising:

flux generating means for generating a magnetic flux, wherein said flux generating means includes a magnet for generating magnetic flux, a first flux guide disposed in contact with said magnet, and a second flux guide arranged in a position to face said magnet and said first flux guide with a gap therebetween;

a Hall element disposed in the path of said magnetic flux, and wherein said Hall element is fixed to one of said magnet and said second flux guide;

holding means for holding said flux generating means and said Hall element integrally therewith, said holding means comprising a molded frame; and

a peripheral circuit provided with said Hall element such that said peripheral circuit is commonly mounted with said Hall element;

wherein said Hall element is fixed to said magnet or said second flux guide, said molded frame completely encapsulating said Hall element, said flux generating means, and said peripheral circuit to fixedly position said Hall element, said flux generating means, and said peripheral circuit relative to each other, and

wherein said magnet or said second flux guide comprises an insulative film formed integrally therein, and said Hall element is fixed to said magnet or said flux guide with said insulative film therein. i