Automatic door control system

An automatic sliding door system of a type wherein at least one door is moved along a linear path between closed and opened positions by means of the rotary drive of an electric motor, said sliding door system comprising:

• sliding door means movable between closed and opened positions;
• motor means to produce bidirectional multispeed rotary drive for driving the sliding door means in opening and closing directions including a drive shaft mounting an encoder means to generate a train of signals upon rotary motion of the drive shaft;
• motor control means to control the direction and speed of said motor means;
• sensor means to detect an activating event and produce an OP signal indicative thereof;
• position means responsive to said train of signals to generate an OCK signal indicative that the door means is opening in an opening check zone, a CCK signal indicative that the door means is closing in a closing check zone, a CP signal indicative that the door means is in a closed position, and a RATE signal indicative of the speed of the drive shaft;
• motion control means responsive to said OP, OCK, CCK, CP, and RATE signals to sequentially control and pace the operation of the motor control means, said motion control means selectively transmitting direction and speed signals to said motor control means;
• and
• reference means to automatically establish a reference open position for said door means, said opening check zone, said closing check zone, and said closed position being defined in relation to said reference open position.

An automatic sliding door system of a type wherein at least one door is moved along a linear path between closed and opened positions by means of the rotary drive of an electric motor, said sliding door system comprising:

• sliding door means linearly movable between opened and closed positions;
• motor means to produce bidirectional multispeed rotary drive for driving said sliding door means;
• motor control means to control the direction and speed of the motor means;
• encoder means to generate a pair of signal trains in accordance with the rotary drive of the motor means;
• decoder means to produce position signals, direction signals and speed signals indicative of the operation of the sliding door means by decoding said signal trains;
• motion control means to provide speed control and direction control signals to the motor control means in response to said position, direction, and speed signals so that said sliding door means is driven by said motor means in a closing direction at a selected speed in accordance with the linear position of the sliding door means and is driven in the opening direction at a selected speed in accordance with the linear position of the sliding door means, said motion control means comprising reference means to automatically establish a reference position for said sliding door means with the linear position of the sliding door means being defined in relation to said reference position.

A method for automatically controlling the operation of a sliding door system of a type wherein at least one door is moved along a linear path between closed and opened positions by means of the rotary drive of an electric motor comprising:

• (a) driving a sliding door system by means of the rotary drive of a multispeed bidirectional motor;
• (b) generating position pulses in accordance with the rotary drive of the motor;
• (c) decoding the position pulses to produce operational position signals indicative of the position and direction of movement movement of said sliding door system;
• (d) processing said operational position signals to produce corresponding motor speed and motor direction signals;
• (e) controlling the speed and direction of said motor in accordance with the motor speed and motor direction signals;
• and
• (f) automatically recording the last stop position of the sliding door system and slowing the sliding door system prior to reaching the last stop position.