Windmill with vertical rotor axis - has sails turned on their lengthwise axes between working and rest positions

摘要

The windmill comprises a rotor on a vertical axis and from which radial sails extend. The sails consist of flat blades (7), each turning on its lengthwise axis between the horizontal rest positon and the vertical working one. A control mechanism holds each in the latter position during that part of a revolution in which it is travelling in the wind direction. This can comprise a cam (12) which is turned round the vertical axis, and against which a follower (14) on each blade works.