Apparatus and method for testing of a rotary movement-electrical signal transducer system

• US 4,428,224 A
• Filed: 07/14/1980
• Issued: 01/31/1984
• Est. Priority Date: 03/23/1979
• Status: Expired due to Term

• Current Assignee: Sun Electric Corp (Snap-On Incorporated)
• Original Assignee: Sun Electric Corp (Snap-On Incorporated)
• Inventors: Frank, Howard L., Farazi, Perry
• Primary Examiner(s): Swisher, S. Clement
• Application Number:
  US06/168,781
• Time in Patent Office: 1,296 Days
• Field of Search: 73/1 R, 73/1 D, 73/2, 73/121, 303/92, 324/186
• US Class Current: 73/1.37
• CPC Class Codes: B60T 2270/406 Test-mode; Self-diagnosis
• CPC Class Codes: B60T 2270/416 Wheel speed sensor failure
• CPC Class Codes: B60T 8/885 using electrical circuitry
• CPC Class Codes: G01P 11/00 Measuring average value of speed by determining time taken to traverse a fixed distance G01P3/64, G01P5/18
• CPC Class Codes: G01P 3/489 Digital circuits therefor
• CPC Class Codes: G01R 23/15 Indicating that frequency of pulses is either above or below a predetermined value or within or outside a predetermined range of values, by making use of non-linear or digital elements (indicating that pulse width is above or below a certain limit)
• CPC Class Codes: G01R 31/00 Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere measuring superconductive properties G01R33/1238; testing or measuring semiconductors or solid state devices during manufacture H01L22/00; testing line transmission systems H04B3/46

Abstract

An apparatus and method for dynamic testing of a rotary movement-electrical signal transducer system, such as found in an automotive anti-blocking system.

Claims

1. A method for testing a rotary movement-electrical signal transducer system of the type generating a series of signals during operation thereof, comprising the steps of:

receiving said signals;

measuring the time of each of said signals to establish the periods therefor;

comparing said periods to determine a maximum period and a minimum period thereof;

determining an average period for said periods;

comparing said average period to said minimum period and said maximum period to provide a first evaluation interval and a second evaluation interval, respectively;

generating a reference interval;

comparing said reference interval to said first evaluation interval and said second evaluation interval; and

generating a postive test signal whenever said first evaluation interval and said second evaluation interval are less than said reference interval.

2. An apparatus for testing a rotary movement-electrical signal transducer system, said system providing a series of pulses during operation thereof, comprising:

input means coupled to said system for receiving said pulses;

means for measuring the time of each of said pulses to establish a series of periods relted to said pulses;

processor means for receiving said series of periods and for determining therefrom a miximum, minimum and average of said periods, said processor means calculating a first evaluation interval from said minimum and said average and a second evaluation interval from said maximum and said average;

said processor means further generating a reference interval and comparing said first evaluation interval and said second evaluation interval thereto, said processor means transmitting a positive test signal whenever said first evaluation interval and said second evaluation interval are less than said reference interval; and

output means for displaying said positive test signal.

3. An apparatus as claimed in claim 2 wherein said input means includes a wave shaping circuit to produce a square wave in response to said pulses.

4. An apparatus as claimed in claim 2 wherein said means for measuring includes a controller, a clock and a counter, said controller being coupled and responsive to said input means, said clock and said counter being coupled and responsive to said controller.

5. An apparatus as claimed in claim 4 wherein said processor means is coupled to said controller and said counter.