Distance-controlled electrically powered unit for actuating rail-mounted curtains

A motor-driven unit that can be remotely controlled for moving a curtain or similar items fitted on a rail and having an operation cord, comprising:

• an electrical power supply,
• a motor with a reversible operation,
• at least one pulley by which the unit can be suspended on the operation cord for a curtain moving operation, without being secured to the wall, such that the operation cord is partially housed over at least part of a perimeter of the at least one pulley and in such a way that the weight of the unit tends to maintain cohesion between the operation cord and the at least one pulley, this weight being enough to compensate for friction exerted by the curtain or the rail itself, and the pulley being provided with the a channel along which the operation cord for operating the curtain is partially housed, said channel having a convergent cross-section,
• a mass which, when held on the operation cord, keeps said operating cord taut,
• a signal receiver,
• a remote control for generating a signal in such a way that movement of the motor in one direction or the other is determined by an order of receipt of a signal from the remote control by the signal receiver, and
• the mass which keeps the operation cord taut and the electrical supply together being comprised of a battery which forms a substantial part of the mass of the motor-driven unit, and
• an electrical circuit for reception and operation of signals received from the remote control, said electronic circuit including:
• said signal receiver,
• an energy-saving circuit which includes a clock circuit that provides timing cycles,
• a program circuit,
• a motor control circuit which controls the motor, and
• a main controller which acts through the program circuit to control the motor control and which opens reception of said signal receiver for a short space of time in each timing cycle.