Door construction and closure means therefor

Claim 1

A PREFABRICATED DOOR UNIT OF THE IMPACT TYPE COMPRISING A UNITARY FRAME MEMBER ADAPTED TO BE INSTALLED IN A WALL OPENING, SAID FRAME MEMBER INCLUDING A VERTICAL PORTION AND A HORIZONTAL PORTION, A ROD PIVOTALLY MOUNTED IN THE VERTICAL PORTION OF THE FRAME MEMBER, A DOOR PANEL SECURED TO THE ROD, A COLLAR DETACHABLY SECURED TO EACH END OF SAID ROD, EACH COLLAR BEING PRESS-FIT WITHIN BEARING MEANS CARRIED BY THE FRAME, WHEREBY A DISPLACEMENT OF THE DOOR PANEL DUE TO IMPACT OR VIBRATION MAY BE COMPENSATED; A MOUNTING PLATE, SAID MOUNTING PLATE HAVING SLOTS FORMED THEREIN, BOLT MEANS EXTENDING THROUGH SAID SLOTS FOR ADJUSTABLY SECURING THE MOUNTING PLATE TO THE HORIZONTAL PORTION OF THE FRAME MEMBER, AN IDLER WHEEL ROTATABLY MOUNTED ON THE MOUNTING PLATE, A DRIVE WHEEL SECURED TO THE ROD, DRIVE MEANS INTERCONNECTING THE IDLER WHEEL AND DRIVE WHEEL, AND SPRING MEANS CARRIED BY THE MOUNTING PLATE AND CONNECTED TO THE DRIVE MEANS BETWEEN THE IDLER WHEEL AND DRIVE WHEEL, WHEREBY WHEN THE DOOR IS OPENED THE SPRING IS COMPRESSED.