A moveable barrier operator with motor speed controlled according to signal pulse length

摘要

A moveable barrier operator 10, eg for a remote-controlled garage door, comprises an electric motor 12 and a transmission 18 driven by the electric motor and connected to the moveable barrier. The barrier operator automatically detects the type of door (single panel 24 or segmented) and uses this information to set a maximum speed of door travel by adjusting, via a controller which controls a length of pluses in a pulse signal, the speed of the motor 12 linearly from zero to a maximum and from the maximum to zero. This linearly variable speed from start of travel to stop provides a smooth and quiet performance. A voltage frequency is automatically detected and this information is used to set a worklight shut-off time. The operator 10 provides full door closure by driving the door into a floor when a DOWN limit is reached and no auto-reverse condition has been detected. A user selects a minimum stop speed for easy starting and stopping of a sticky or binding door. A flasher light which can indicate that the door is about to be moved by the barrier operator.