出版社：National Institute of Occupational Safety and Health
摘要：An acceleration measuring apparatus in Z direction with about 50 gr weight and a mechanical hand for simulating the human hand were constructed so as to measure isolation effectiveness of vibration isolation gloves. The glove, the acceleration measuring apparatus and the model hand were pressed in this order by an air-cylinder by about 1 kg/cm2 on a vibration table of electro-dynamic type. The vibra-tion frequency was swept from 10 to 1000 Hz in order to measure insertion loss of the glove. Thirteen samples of gloves commercially available were examined, but their isolation effectiveness could not be observed below about 200 Hz. The resonance frequency determined approximately from spring constant of the glove, the mass of the acceleration measuring apparatus and the first mass of the model hand (0.05+0.2kg) was quite important to estimate the cutoff frequency of the attenua-tion characteristic of the glove, namely, the gloves were non-effective below this resonance frequency but they showed attenuation near 12 dB/oct above this resonance. The force measurement was made to decide the vibration isolation effectiveness of the glove instead of acceleration measurement, so that the accuracy of the measurement was checked. The results agreed with those derived from the accel-eration measurement above the resonance frequency.
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