Title:
VOLUME SPEED MEASURING METHOD AND DEVICE
Document Type and Number:
Japanese Patent JP3656357
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To carry out an accurate and speedy arithmetic operation of a volume speed by arithmetically operating the volume speed based on a sound pressure generated by a sound source oscillation face which is measured by a microphone installed in a guiding pipe having a constant sectional area and the sectional area of the guiding pipe.
SOLUTION: A guiding pipe 12 has a constant sectional area, which opposed ends are opened in the vicinity of an oscillation face 11 of a sound source which faces one end of the pipe 12 in which a microphone 13 is installed. An output signal of the microphone 13 is given to an FFT arithmetic unit 15 via an amplifier 14. The unit 15 which preliminarily stores a known constant such as a sectional area of a guiding pipe therein calculates a volume speed by integrating the sound pressure measured by the microphone 13 and converted into a digital signal through the amplifier 14 and the sectional area of the guiding pipe by using a specified numerical relation. Accordingly, it is possible to obtain a volume speed accurately and in a short time without measuring the area of sound oscillation face and the oscillation speed individually.
Inventors:
Masahiro Nakamura
Application Number:
JP7764097A
Publication Date:
June 08, 2005
Filing Date:
March 28, 1997
Export Citation:
Assignee:
Isuzu Motors Limited
International Classes:
G01H3/12; G01H5/00; (IPC1-7): G01H5/00; G01H3/12
Domestic Patent References:
| JP8159864A | ||||
| JP2049123A | ||||
| JP9229758A | ||||
| JP62115326A | ||||
| JP61140826A |
Attorney, Agent or Firm:
Shuji Moizumi