System and related methods for detecting an obstruction in the path of a garage door controlled by an open-loop operator

An internal entrapment system for a sectional door movable between a closed position proximate a door frame and an open position displaced therefrom, wherein the door frame includes vertically spaced apart jamb members connected at their tops by a horizontal header, comprising:

• a housing affixed to the horizontal header;
• a counter-balancing system which has a motor with a drive gear carried by said housing;
• a drive shaft coupled to said drive gear, said drive shaft coupled to the door for moving the door from the closed position to the open position and said drive shaft freely rotating when the weight of the door is released as it moves from the open position t the closed position;
• a potentiometer having a slider element coupled to said drive gear to provide a plurality of positional locations of the door as the door moves between the open and closed positions;
• a pulse counter coupled to said drive shaft to detect the speed thereof;
• and
• a controller connected to said motor, said potentiometer and said pulse counter, said controller determining a torque value applied by said drive shaft from said pulse counter and associating the torque value with each said plurality of positional locations of the door determined by said potentiometer, wherein said controller takes corrective action if the difference between the motor torque value for one of said plurality of positional locations and one of a plurality of door profile data points associated with each of said plurality of positional locations exceeds a predetermined threshold, and wherein said controller updates said plurality of door profile data points to the motor torque values for each respective said plurality of positional locations if the predetermined threshold is not exceeded by any of the differences between the motor torque values and said plurality of door profile data points.

An internal entrapment system used with an open-loop garage door operator for at least stopping motion of a sectional garage door during a closing or opening cycle when the door is interfered with by an obstruction, comprising:

• means for moving the garage door between an open position and a closed position, wherein said moving means includes a motor with a drive shaft that only drives the door from said closed position to said open position, said drive shaft freely rotating when the weight of the door is released as the door moves from the open position to the closed position;
• a potentiometer coupled to said moving means to detect a plurality of speed values of the moving garage door and to set an upper and a lower limit of door travel, wherein said potentiometer includes a slider element coupled to the door which generates a voltage value that is directly proportional to the door position to establish said upper and lower limits of door travel, and wherein said voltage value changes depending upon the door position and wherein said slider element remains in place even if a power supply is removed from said potentiometer;
• and
• a processor with memory to store said plurality of speed readings, said processor calculating a plurality of force values from said plurality of speed values between the upper and lower limits and taking corrective action by controlling said moving means when said processor detects that a force applied by said moving means is beyond a predetermined threshold.

An internal entrapment system for a garage door controlled by a garage door operator, comprising:

• means for transferring the garage door between vertical and horizontal positions;
• an emitter having an unobstructed view of the garage door, said emitter projecting an incident signal toward the garage door which returns a reflected signal;
• a receiver for receiving said reflected signal;
• and
• a processor for analyzing a plurality of said reflected signals and stopping operation of said transferring means when the analysis reveals that the garage door is no longer moving and said processor receives signals from said transferring means that the garage door should be moving.

A motion-initiated system for a garage door controlled by a garage door operator, comprising:

• means for transferring the garage door between vertical and horizontal positions;
• an emitter having an unobstructed view of the garage door, said emitter projecting an incident signal toward the garage door which returns a reflected signal;
• a receiver for receiving said reflected signal;
• and
• a processor for analyzing a plurality of said reflected signals and starting operation of said transferring means from one of an open and closed positions to the other position when the analysis reveals that the movement is initiated by means other than said means for transferring.