| 摘要 |
According to the invention, this device comprises: - a rotor 1 which can revolve about the said axis; - position marking means 4, 5, 13, 14; - a cylindrical skirt 7 integral with the said rotor and coaxial with the said axis, provided with an alternating arrangement of transparent areas 8 and opaque areas 9; - a radiation source 15, arranged stationary and sending a beam through the said skirt; and - two sensors 16, 17 which can pick up the said radiation beam and are arranged in a stationary manner in order to receive the said beam after it has passed through the said skirt. <IMAGE>
|
