Wall surface suction-type travel device

A wall surface suction-type travel device configured to travel on a wall surface while being suctioned on the wall surface, the wall surface suction-type travel device comprising:

• a plurality of decompression chambers being recessed and facing the wall surface;
• an intermediate chamber communicating with each of the plurality of decompression chambers;
• a suction device sucking in air from the intermediate chamber to decompress the intermediate chamber;
• a plurality of principal communicating parts allowing the respective decompression chambers to communicate with the intermediate chamber;
• a plurality of secondary communicating parts allowing the respective decompression chambers to communicate with the intermediate chamber;
• and
• a plurality of valves facing openings of the respective principal communicating parts,
• wherein an area of an opening of each of the plurality of secondary communicating parts is smaller than an area of the opening of a corresponding one of the plurality of principal communicating parts, and
• wherein on condition that pressure in one of the plurality of decompression chambers gets higher than pressure required for wall surface suction, a consequent difference in pressure between the one of the decompression chambers and the intermediate chamber causes a corresponding one of the plurality of valves to close the opening of a corresponding one of the plurality of principal communicating parts.