Apparatus for testing Hall effect device

• US 5,032,791 A
• Filed: 08/04/1989
• Issued: 07/16/1991
• Est. Priority Date: 08/04/1989
• Status: Expired due to Fees

• Current Assignee: A&E Manufacturing Co.
• Original Assignee: E & E Manufacturing Company, Inc.
• Inventors: Bates, James F. Jr.
• Primary Examiner(s): Wieder, Kenneth A.
• Assistant Examiner(s): Solis, Jose M.
• Application Number:
  US07/389,411
• Time in Patent Office: 711 Days
• Field of Search: 324/381, 324/383, 324/385, 324/386, 324/202, 324/537, 324/117 H
• US Class Current: 324/202
• CPC Class Codes: G01R 31/2637 for testing other individual devices G01R31/2608 - G01R31/2632, G01R31/27 take precedence
• CPC Class Codes: G01R 33/1253 Measuring galvano-magnetic properties

Abstract

An apparatus for testing the operativeness of a Hall effect device (HED), such as in an automotive application, without requiring removal of the HED for testing. The apparatus includes a connector for connection to the HED, a connector for connection to a voltage supply, and an indicator. A permanent magnet is physically positioned with respect to the HED so that a properly functioning HED would produce a Hall effect current within a predetermined range. A ferrous metal strip is provided, shiftable between an interference position between the permanent magnet and the HED and a clear position not between the permanent magnet and the HED. The indicator is connected so as to be lit when the HED is producing a current within the predetermined range, and not lit when the HED is not producing a current within the predetermined range. Also disclosed is a method for testing the operativeness of a HED. The method includes supplying a testing apparatus as described above. The apparatus is connected to inputs of the HED, and the indicator observed. The metal strip is then positioned between the permanent magnet and the HED, and the indicator observed, to determine whether the HED is producing a current of at least the predetermined level. In a disclosed embodiment, the HED constitutes part of a vehicle engine distributor, and the ferrous metal strip may be a distributor rotor vane.

Claims

1. A method for testing the operativeness of a Hall effect part of a vehicle engine distributor, said Hall effect part including a Hall effect device having inputs and outputs, a permanent magnet physically positioned with respect to said Hall effect device so that a properly functioning Hall effect device produces a Hall effect current within a predetermined range, and field blocking means alternatively positionable between and not between said permanent magnet and said Hall effect device, said method comprising the steps of:

supplying a testing device electrically connectable to said Hall effect part, said testing device comprising;

a current supply for providing a current to the inputs of said Hall effect device;

means for connecting said apparatus to said Hall effect device; and

an indicator associated with said connecting means, which indicator is active when said Hall effect device is producing a current within said predetermined range, and not active when said Hall effect device is not producing a current within said predetermined range;

connecting said device to said Hall effect inputs, thereby providing a current to said inputs;

observing said indicator to determine whether said Hall effect device is producing a current of said predetermined level;

positioning said field blocking means between said permanent magnet and said Hall effect device; and

observing said indicator to determine whether said Hall effect device is producing a current of said predetermined level.

2. A hand tool for testing a Hall effect part of a vehicle, said Hall effect part including a Hall effect device having inputs and outputs, a permanent magnet physically permanently positioned with respect to said Hall effect device so that a properly functioning Hall effect device would produce a Hall effect current within a predetermined range, said hand tool comprising:

a battery for providing a current to the inputs of said Hall effect device;

first connecting means for connecting said battery to said hand tool;

second connecting means for connecting said hand tool to said Hall effect device;

a light indicator connected between said first and second connecting means, which light indicator is lit when said Hall effect device is producing a current within said predetermined range, and not lit when said Hall effect device is not producing a current within said predetermined range.

3. A hand tool as recited in claim 2, further comprising field blocking means alternatively positioned between and not between said permanent magnet and said Hall effect device, such that if said Hall effect device is functioning properly said light indicator will be on when said field blocking means is not between said permanent magnet and said Hall effect device and will be off when said field blocking means is between said permanent magnet and said Hall effect device.

4. A hand tool as recited in claim 3 wherein said field blocking means comprises a strip of ferrous metal insertable between said permanent magnet and said Hall effect device.

5. A hand tool as recited in claim 2, wherein said indicator comprises a light emitting diode and a series resistor connected in circuit with said outputs of said Hall effect device.