| 摘要 |
PROBLEM TO BE SOLVED: To attenuate noise in a mechanical multistory parking lot to around 40 dB to allow it to be preferably used also at night in a zone where quietness is required.SOLUTION: A soundproof cover 5 for covering a motor 4 is arranged over the motor 4 which lifts a lifting frame 3 having a car-loaded pallet 32. Under a partial opening in an underside of the soundproof cover 5, a cylindrical noise attenuation box 6 with an open underside is arranged. In the attenuation box 6, partial partition panels 62 are provided at vertical intermediate positions of the inner wall surface thereof and an S-shaped or M-shaped curved communication passage 63 is formed inside thereof, and sound of the motor is attenuated by the inner wall and sound absorption and sound insulation materials 7 of the partial partition panels 62. Furthermore, vibration-proof materials 8 are interposed in positions where vibration is generated due to the rotary-driven motor 4. Noise is attenuated by 6 to 7 dB by the vibration-proof materials 8, and further attenuated by a few dB by the soundproof cover 5 and the noise attenuation box 6. Thus, the noise can be suppressed to 50 dB or less. |
