Electric drive for stage curtain - with DC motor inside guide rail with plastic stops and pickup wipers for conductor rails

摘要

The stage curtain is draped from a series of runners inside hollow section guide rails. The edges of the curtain have electrically driven trolleys (5) which pick up the current using wipers (3) on each side and conductor rails (4) on the inside walls of the guide rails. The wipers are set to point fore and aft and the circuitry is arranged so that the leading wiper picks up the drive current for the DC motor, while the trailing wiper is blocked by a diode. In order to stop the drive at selected points special plastic inserts (7) are slid into the guide rails. These engage the leading wiper and lift it of the track, and stop the drive. The trailing wiper remains in contact with the track and when the polarity is reversed it provides traction for the motor.