Door structure

Claim 1

A DOOR STRUCTURE COMPRISING A PLURALITY OF LATERALLY DISPOSED PANELS IN SUBSTANTIALLY PARALLEL PLANES, SIDE FRAME MEMBERS HAVING A PLURALITY OF SPACED CHANNELS OF PROGRESSIVELY INCREASING LENGTH, EACH PANEL BEING DISPOSED IN A SEPARATE ONE OF SAID CHANNELS, WHEREBY EACH PANEL IS DISPLACEABLE ALONG ITS RESPECTIVE CHANNEL BY AN AMOUNT DETERMINED BY THE LENGTH OF THE CHANNEL, ENGAGEMENT MEANS ON EACH PANEL FOR ENGAGING THE NEXT ADJACENT PANEL WHEN A DISPLACED PANEL HAS BEEN MOVED TO A POSITION SUBSTANTIALLY EQUIDISTANT WITH SAID ADJACENT PANELS FROM A FIXED END PANEL, MEANS FOR RECIPROCABLY DISPLACING THE PANELS SUCCESSIVELY BEGINNING WITH THE END PANEL OPPOSITE SAID FIXED PANEL, SAID DISPLACING MEANS INCLUDING AN ENDLESS FLEXIBLE MEMBER HAVING ONE PORTION COUPLED TO ONE SIDE OF SAID OPPOSITE END PANEL AND A SECOND PORTION COUPLED TO THE OTHER SIDE OF SAID OPPOSITE END PANEL, MOTOR MEANS FOR DRIVING SAID ENDLESS MEMBER, SAID MOTOR MEANS BEING MECHANICALLY COUPLED TO SAID ENDLESS MEMBER TO DRIVE IT, BRAKE MEANS FOR ARRESTING THE DISPLACEMENT OF SAID PANELS AT ANY POSITION, SAID BRAKE MEANS INCLUDING A HOLLOW FLEXIBLE MEMBER EXTENDING ALONG THE END OF SAID END PANEL, SWITCH MEANS RESPONSIVE TO THE DISTORTION OF SAID FLEXIBLE MEMBER FOR CLOSING AN ELECTRIC CIRCUIT, SAID SWITCH BEING CONNECTED IN CIRCUIT RELATION WITH A SOLENOID HAVING A MECHANICAL ACTUATOR, SAID MECHANICAL ACTUATOR BEING CONNECTED TO A PIVOTALLY MOUNTED LEVER, SAID LEVER BEING CONNECTED FOR ROTATING A THREADED MEMBER THREADABLY SUPPORTED BY A BRACKET, A BRAKE DISC CONNECTED TO AND ROTATABLE WITH SAID MOTOR MEANS, SAID THREADED MEMBER BEING MOUNTED WITH ONE OF ITS ENDS ADJACENT SAID DISC, WHEREBY ROTATION OF SAID THREADED MEMBER BY SAID LEVER CAUSES SAID ONE END TO BE LONGITUDINALLY DISPLACED TO FRICTIONALLY ENGAGE SAID DISC.