Tester for mass airflow sensor
US5379627A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 3, 1992 |
| Grant date | Jan 10, 1995 |
| Priority date | — |
| Expiry date | Jun 3, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F25/10
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device for testing the mass airflow sensor for a motor vehicle provides for connecting the positive and negative terminals of dc source to the corresponding positive and negative terminals on the mass airflow sensor. A circuit comprised of an LED and a resistor connected in series has one end connected to the positive terminal of the dc source and another end connected to the signal output terminal of the MAF sensor during a test. If, after the tester is connected to the dc source and to the MAF sensor the LED does not flash at all or burns continuously, it is a first indication of a defective MAF sensor. Because the flash or pulse rate of the signals driving the LED are too fast for visual counting, a tachometer or frequency meter is connected between the LED circuit and the negative terminal of the dc source. The meter needle deflects on a scale calibrated in terms of frequency or engine rpm which quantities are both related to mass airflow. The relationship between airflow variations as represented by the tachometer or frequency meter readings is determined by referring the meter readings to charts provided by the manufacturer of the mass airflow sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.