Patent ID: 7835883
Filing Date: 2010-11-16
Classification: G01P,H02P

Abstract:
1. A device for measuring rotation speed of rotating equipment, comprising: a position sensor configured to output position signals indicating M number of rotation positions of a equal phase difference in each one rotation of the rotating equipment where M is an integer equal to or greater than 2; a clock signal generator configured to generate a basic clock signal; a counter configured to count the number of pulses of the basic clock signal; a measuring interval setting unit configured to set a duration coefficient that indicates a ratio of a measuring interval during a first time period between two successively occurring position signals and a second time period between two successively occurring position signals, where the measuring interval setting unit causing the counter to count the number of pulses of the basic clock signal during the measuring interval; a duration coefficient adjusting unit configured to adjust the duration coefficient such that a count value obtained in the measuring interval lies within a limit value; and a calculating unit configured to calculate a rotation speed of the rotating equipment as a function of the frequency of the basic clock signal, the integer M, the duration coefficient, and the count value obtained by the counter during the measuring interval.