<；P>；PROBLEM TO BE SOLVED: To provide a ventilation apparatus for a greenhouse designed so as to prevent such malfunction that a ventilation member is kept open at a prescribed open angle due to unintended movement of an operative mechanism. <；P>；SOLUTION: The ventilation apparatus for greenhouse is installed in the main body part 2b of the operative mechanism 2. The main body part 2b is provided with a movable member 9 movable up and down independent of the main body part 2b, a push spring 11 intervening between the movable member 9 and the main body part 2b and energizing the movable member 9 in its descending direction, a guide pin 7 installed at the front edge part of a locking member 6, and a path 10 which is formed in the movable member 9 and through which the guide pin 7 is movably inserted. The path 10 has a first area 10a in which the guide pin 7 is engaged to inhibit the locking member 6 from rotating in one direction, and a second area 10b communicating with the first area 10a to rotate the guide pin 7 getting out of the first area 10a. Further the apparatus is provided with a first linear member 12 connected to the movable member 9 and pulled to move the movable member 9 in its rising direction. <；P>；COPYRIGHT: (C)2008,JPO&INPIT
