PROBLEM TO BE SOLVED: To enable a drawing tool to be attached to a part which contacts with another member, and to reduce a part left when collecting a curtain.SOLUTION: In an opening/closing mechanism for a greenhouse curtain, when a drawing tool 20 contacts with a stationary beam 500, the drawing tool 20 is rotated in a direction falling from a standing attitude and becomes in a tilted attitude, and when separating from the stationary beam 500, the drawing tool 20 is rotated in a standing direction from the tilted attitude and becomes in the standing attitude. Consequently, when closing a curtain, in a case where the stationary beam 500 such as a plastic film is stretched in the vicinity of a terminal in a moving direction of a guidance pipe 200, the drawing tool 20 is not caught in the stationary beam and the curtain drawn by the guidance pipe 200 can be closed to a region overlapping the stationary beam since the drawing tool 20 is tilted by contacting with the stationary beam 500. Further, the stationary beam can be arranged on a rack wire, an attachment structure of the stationary beam can be simplified, and a clearance in a vertical direction between the stationary beam and the curtain can be reduced.
