ABSTRACT
Rotational speed is the primary physics data during the operation of various motors. It's extremely important to measure the rotational speed precisely, instantaneously and conveniently.
Nowadays the rotational speed-measuring methods; which are uncommon use in the country and abroad, includes: the eccentric turn-meter, the rotational speed-measuring dynamotor, the flashlight, the photo electricity coder, the Hall sensor. Via the research into the existing measuring methods of electric motor, it's discovered that electric motors consummates too much power and even some of them cannot run the trumpeter and rotational speed-measuring dynamotor. The recruit is caused because eccentric remitter is attached to electric motor rotor directly. Based on the fact that both tempter and rotational speed-measuring dynamotor don't apply to the rotational speed-measuring of electric motor, it's essential to put-forward non-contact rev-measuring method. With scientific analysis of principle (non-contracture-measuring)of method. More details about how to make photo electricity coder and sensor are introduced in this article. Three types of circuits are presented: ①the photo electricity coder LED-displaying digital circuit ②the photo electricity coder LED-displaying single-chip microcomputer control ③the photo electricity coder LCD-displaying single-chip microcomputer control. Specific circuits designed for each style after analyzing the circuit's composing, operation principle, calculating formula, component's logic parameter and characteristics. To the circuit operated by single-chip microcomputer, the method of software-design is analyzed and the procedure flow diagram/procedure lists are also provided.
With those three methods mentioned above, a new type of trumpeter can be developed. This new trumpeter has advantage in convenience if installation and maintenance. It can operate steadily, measure accurately too. The latest turnmeter's application and dissemination would be marketable and profitable.
KEY WORDS: electric motor, single-chip, sensor, non-contacting, rev-measuring