| 摘要 |
PROBLEM TO BE SOLVED: To open and close a vertical film in greenhouse by a simple and inexpensive device. SOLUTION: The upper edge of a film (27) is fixed to a horizontal supporting lever (25) and the lower edge of the film is fixed on a horizontal winding shaft (29) and a nearly conical body (33) is provided at the end of the horizontal rolling shaft (29) and a double-thread screw (35a) is formed on the nearly conical body and a reel (41) is provided on an output shaft of a motor (37) whose position is fixed and the upper end of a first string (43) is fixed on the reel and the lower end of the first string is fixed around either screw of the nearly conical body and the upper end of the second string (45) is fixed around the other screw of the nearly conical body and the lower end of the second string is fixed to the lower position. Then, the first string and the second string are inserted into each screw at the position having nearly same diameter as a diameter (31a) of a roll-shaped part (31) in which the film is rolled around the horizontal winding shaft. |
