AUTOMOTIVE TESTING DEVICE AND METHOD OF USE

申请公布号：

WO1991009318(A1)

申请号：

US1990006151

申请日期：

1990.10.25

申请公布日期：

1991.06.27

摘要：

<p>A tester and method for testing a variable output sensor (38) such as in an automobile. The sensor (38) to be tested has two device output terminals (14 and 16), one of which may be simply the connection of the sensor body to engine ground. The sensor (38) varies the signals at the output terminals depending upon a sensed condition. The tester includes a zero crossing detector (12) having two input terminals (14 and 16) and an output terminal (18), the latter producing a signal whenever the signals at the two input terminals (14 and 16) are not substantially the same. The tester further includes connections for connecting the input terminals of the zero crossing detector to the output terminals of the sensor, and an indicator (24) connected to the output terminal of the zero crossing detector. The indicator (24) is activated whenever the output terminal of the zero crossing detector produces a signal. In one embodiment the zero crossing detector (12) comprises a voltage comparator (22) which produces a positive signal when the first input signal is greater than the second input signal, a negative signal when the first input signal is less than the second input signal, and no signal when the first input signal is substantially the same as the second input signal. The method includes connecting the tester to the sensor (38), repeatedly activating and de-activating the sensor (38) to cause it to produce varying signals, and observing the indicator (24) to determine whether it changes from active to inactive or vice vesa.</p>