NOISE REDUCING DEVICE FOR CONSTRUCTION MACHINE OPERATOR' S CAB AND CONSTRUCTION MACHINE OPERATOR'S CAB

摘要

PROBLEM TO BE SOLVED: To provide a noise reducing device for a construction machine operator's cab capable of sufficiently reducing the noise in the operator's cab without deteriorating comfortability and to provide the construction machine operator's cab. SOLUTION: This noise reducing device for the construction machine operator's cab 3 is provided in the operator's cab 3 of a construction machine having operation levers 41, 42 for controlling the pressure oil fed to hydraulic cylinders 7a-7c from the hydraulic pump 33 of the construction machine. The noise reducing device is provided with a microphone 43 detecting the noise in the operator's cab 3, an extraction section 45b extracting the component of the prescribed frequency band in the detected noise, a phase extraction section 45d extracting the component of the frequency baud and a speaker 44 and outputting the inverted component in the operator's cab 3.