To prevent the pressure loss of the air-flow force even in the change of air-flow direction by mounting a blower part on a turn table for blowing the air from a blast port by means of a motor provided with a fan.

A blower part 14 of an air blower 13 is mounted on an upper part of a carriage 15 through a turn table 16. The blower part 14 comprises a rear duct 18 comprising an inlet port 17, and a front duct 20 comprising an blast port 19 and narrowed along the blasting direction for contracting the air-flow. A motor 22 attached with a fan 21 is mounted on the rear duct 18, and the fixed louvers 23... are laterally arranged on the blast port 19 of the front duct 20 for controlling the air blasting direction approximately same as the flowing direction inside the blower part 14. The air blower 13 is lifted up by a jack 24 mounted on an edge near the inlet port 17 and the blast port 19 of the blower part 14, and positioned and fixed after the air-flow direction of the air blower 13 is determined by means of the turn table 16.