Revolution indicator and a program for the revolution indicator
First Claim
1. A revolution indicator, comprising:
- a detecting portion which detects a physical phenomenon resulting from the revolving movement of a measuring object;
a FFT computation portion which performs a fast Fourier transform of the data detected by the detecting portion under a specific data length, and computes and outputs the analytical data; and
a revolution computing portion which computes the number of revolutions of the measuring object based on the analytical data output from the FFT computation portion, whereina variation determination portion is equipped, which makes the FFT computation portion compute the first analytical data continuously based on the data successively detected by the detecting portion under the first data length and determines whether there is any variation or not in the first analytical data computed continuously, andwhen there is a variation in the first analytical data computed continuously, the variation determination portion makes the FFT computation portion output the first analytical data computed under the first data length to the revolution computing portion, andwhen there is no variation in the first analytical data continuously computed, it makes the FFT computation portion compute the second analytical data under the second data length which is longer than the first data length and output to the revolution computing portion.
1 Assignment
0 Petitions
Accused Products
Abstract
The object of the invention is providing a revolution indicator and a program for the indicator, which can detect a varying number of revolutions precisely. The indicator includes: a detecting portion detecting a physical phenomenon resulting from the revolution movement of a measuring object; a FFT computation portion performing a fast Fourier transform of the data detected by the detecting portion under a specific data length, and computing and outputting the analytical data; and a revolution computing portion computing the number of revolutions of the measuring object based on the analytical data output from the FFT computation portion. A variation determination portion is equipped, which makes the FFT computation portion compute the first analytical data continuously, based on the data successively detected by the detecting portion under the first data length and determines whether there is any variation or not in the first analytical data computed continuously.
-
Citations
7 Claims
-
1. A revolution indicator, comprising:
-
a detecting portion which detects a physical phenomenon resulting from the revolving movement of a measuring object; a FFT computation portion which performs a fast Fourier transform of the data detected by the detecting portion under a specific data length, and computes and outputs the analytical data; and a revolution computing portion which computes the number of revolutions of the measuring object based on the analytical data output from the FFT computation portion, wherein a variation determination portion is equipped, which makes the FFT computation portion compute the first analytical data continuously based on the data successively detected by the detecting portion under the first data length and determines whether there is any variation or not in the first analytical data computed continuously, and when there is a variation in the first analytical data computed continuously, the variation determination portion makes the FFT computation portion output the first analytical data computed under the first data length to the revolution computing portion, and when there is no variation in the first analytical data continuously computed, it makes the FFT computation portion compute the second analytical data under the second data length which is longer than the first data length and output to the revolution computing portion. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A program to make the revolution indicator execute the following steps, including:
-
a detecting step to detect a physical phenomenon resulting from the revolving movement of a measuring object; a FFT computation step in which the detected data in the detecting step is fast-Fourier-transformed under a specific data length and the analytical data is computed and output; and a revolution computing step to compute the number of the revolutions of the measuring object based on the analytical data output in the FFT computing step, wherein the program for revolution indicator includes following steps; a step to make the FFT computing step compute the first analytical data continuously under the first data length based on the data successively detected in the detecting step, and makes it execute a variation determination step to determine whether there is a variation or not in the continuously computed first analytical data, and when there is a variation in the first analytical data computed continuously, the variation determination step makes the FFT computing step output the first analytical data computed under the first data length to the revolution computing step, and when there is no variation in the first analytical data computed continuously, it makes the FFT computing step compute the second analytical data under the second data length which is longer than the first data length and output to the revolution computing step.
-
Specification