Tubular linear synchronous motor door and encoder-less control

A method for controlling elevator mounted tubular linear synchronous motor doors comprising the steps of:

• inputting a position control profile (40) to a master-slave control circuit (50);
• measuring an actual master position (53) of a master door having a master status;
• providing as an input to said master door said position control profile (40);
• comparing said measured actual master position (53) to said position control profile (40) to compute a master position error (51);
• using said computed master position error (51) to calculate a master electrical force (57);
• transmitting said calculated master electrical force (57) to said master door;
• recomputing said actual master position (53);
• providing as an input said actual master position (53) to a slave door having a slave status;
• measuring an actual slave position (54) of said slave door;
• comparing said measured actual slave position (54) to said inputted actual master position (53) to compute a slave position error (52) using said computed slave position error (52) to calculate a slave electrical force (58);
• transmitting said calculated slave electrical force (58) to said slave door;
• and
• toggling the status of said slave door and said master door when an absolute value of said slave position error (52) exceeds a predefined threshold.

An apparatus for controlling tubular linear synchronous motor doors comprising:

• a master-slave control circuit (50) capable of measuring an actual master position (53) of a master door having a master status and an actual slave position (54) of a slave door having a slave status;
• a position control profile (40) accessible to said master-slave control circuit (50);
• means for comparing said measured actual master position (53) to said position control profile (40) to compute a master position error (51);
• means for calculating a master electrical force (57) from said computed master position error (51);
• means for transmitting said calculated master electrical force (57) to said master door;
• means for providing as an input said actual master position (53) to said slave door;
• means for measuring an actual slave position (54) of said slave door;
• means for comparing said measured actual slave position (54) to said inputted actual master position (53) to compute a slave position error using said computed slave position error (52) to calculate a slave electrical force (58);
• means for transmitting said calculated slave electrical force (58) to said slave door;
• and
• means for toggling the status of said slave door and said master door when an absolute value of said slave position error (52) exceeds a predefined threshold.