Gear noise evalutation system

• US 5,574,646 A
• Filed: 02/29/1996
• Issued: 11/12/1996
• Est. Priority Date: 02/29/1996
• Status: Expired due to Fees

• Current Assignee: Isuzu Motors Limited
• Original Assignee: Isuzu Motors Limited
• Inventors: Kawasaki, Yoshiki, Karube, Masahiko, Nishioka, Tatsuhiko
• Primary Examiner(s): Voeltz, Emanuel T.
• Assistant Examiner(s): MILLER, CRAIG S
• Application Number:
  US08/609,944
• Time in Patent Office: 257 Days
• Field of Search: 73/660, 364/431.01, 364/431.03, 364/431.04, 364/431.07, 364/431.08, 364/511, 364/551.01, 364/274.9, 364/276.6, 364/156, 364/157, 364/972.4 , 364/424.03, 364/424.04, 364/507, 364/508
• US Class Current: 701/111
• CPC Class Codes: G01M 13/028 Acoustic or vibration analysis

Abstract

A gear noise evaluation system having a neuro-computer which is provided with sound pressure values from an FFT analyzer. At this time, an evaluator simultaneously presets an absolutely sensual evaluating value as a teacher signal from a control bench. The neuro-computer repeatedly performs a learning so that the pressure values may become the absolutely sensual evaluating value until the difference between the sound pressure value and the sensual evaluating value lies in a permissive error range thereby determining a function value.

Claims

1. A gear noise evaluation system comprising;

a tachometer for detecting a rotative speed of a shaft on which a gear is mounted;

a microphone for detecting a noise from said gear;

an FFT analyzer which repeatedly receives as an input the rotative speed from said tachometer and the noise from said microphone and provides as an output a sound pressure value with respect to the rotative speed for a predetermined gear position;

a control bench where the rotative speed of the shaft is indicated and changed by an evaluator presetting an absolutely sensual evaluating value as a teacher signal with respect to the rotative speed of the shaft; and

,

a neuro-computer which receives as an input the sound pressure value from said FFT analyzer, learns to attain the absolutely sensual evaluating value, stops learning when the difference between the sound pressure value and the absolutely sensual evaluating value from said control bench lies in a permissive error range thereby determining a function value.

2. A gear noise evaluation system as claimed in claim 1, wherein said neuro-computer comprises a sensually evaluating screen for displaying the absolutely sensual evaluating value obtained by a predetermined operation based on the function value.

3. A gear noise evaluation system as claimed in claim 1, further comprising a digital audio tape for taking in the rotative speed from said tachometer and the noise from said microphone and means for sampling data of said digital audio tape and for providing the sampling data for said FFT analyzer.

4. A gear noise evaluation system comprising;

a tachometer for detecting a rotative speed of a shaft on which a gear is mounted;

a microphone for detecting a noise from said gear;

a converter for converting the frequency of the rotative speed from said tachometer into a plurality of side band frequencies;

an FFT analyzer which repeatedly receives as inputs the side band frequencies from said converter and the noises from said microphone and provides as outputs side band sound pressure values with respect to the side band frequencies from said converter for a predetermined gear position;

a control bench where the rotative speed of the shaft is indicated and changed by an evaluator presetting an absolutely sensual evaluating value as a teacher signal with respect to the rotative speed of the shaft; and

,

an operation unit which repeatedly receives as inputs the side band sound pressures from said FFT analyzer to determine the average value of sound pressure values other than the side band sound pressure values and performs operations corresponding to the changed frequency of the rotative speed so that the square root of the sum of the squared value, multiplied with a coefficient, of the deviation between the side band sound pressure values from said FFT analyzer and the average value becomes the absolutely sensual evaluating value from said control bench, the coefficient being determined by simultaneous equations.

5. A gear noise evaluation system as claimed in claim 4, wherein said operation unit comprises a sensually evaluating screen for displaying the absolutely sensual evaluating value obtained by a predetermined operation based on the coefficient.