PURPOSE: To reduce the resistance of air pressure, by providing a dodger so that its one end is secured on a winding shaft in a housing and can be wound up like a shutter in the housing and by winding up the dodger in the housing when not needing the dodger.

CONSTITUTION: A housing 4 is provided at the end of a dodger. The end of the dodger is secured on a winding shaft in the housing 4 so that the main part 3 of the dodger can be wound up like a shutter. A pair of upper and lower guide rails 2a, 2b are provided at the upper and lower edges of the doger. A guide bar 6 is provided at the middle part of the dodger. When the main part 3 of the dodger is moved into and out of the housing 4, the main part is guided by the rails 2a, 2b and the bar 6. A wind breaker 7 may be rotatably provided on the upper guide rails 2a over the dodger. Since the main part 3 of the dodger is wound up into the housing 4 when the dodger is not needed, the resistance of air pressure is diminished.