Door frame truing apparatus

Claim 1

In a portable machine for truing a continuous door sealing flange of a high temperature furnace or oven, a substantially rectangular base support frame having a pair of transversely spaced-apart substantially parallel longitudinal side members and a first pair of spaced-apart parallel rail members connected across said pair of side members and defining an open central portion therewith, means for removably securing said base support frame in position with respect to the flange being trued, a movable secondary frame having a pair of transversely spaced-apart substantially parallel longitudinal side members and a pair of spaced-apart parallel transverse end members connected across said pair of side members and defining an open central portion therewith, said secondary frame having rail-engaging means for moving it for back and forth movement along said first pair of rail members transversely across said base support frame, a second pair of spaced-apart parallel rail members mounted to extend longitudinally along said pair of longitudinal side members of said secondary frame, an overhead tertiary frame having a pair of transversely spaced-apart parallel longitudinally extending side members and having rail-engaging means for mounting said tertiary frame for back and forth movement along said second pair of rails with respect to said secondary frame in a substantially right angular direction with respect to movement of said secondary frame along said base support frame, said tertiary frame defining an open central portion, motor-driven milling means operatively carried by said tertiary frame and having a truing head extending therefrom through the open central portions of said tertiary and secondary and base support frames for engagement with and movement along the door sealing flange as effected by movements of said tertiary and secondary frames with respect to said base support frame and each other, first motor means mounted on one longitudinal side member of said base support frame, a first screw shaft at one end operatively connected to said first motor means and extending therefrom transversely of said base support frame, a first screw block carried by one longitudinal side member of said secondary frame and receiving a forward end portion of said first screw shaft therein for moving said secondary frame transversely back and forth along said first pair of rails with respect to said base support frame, a second motor means mounted adjacent one end of and on the other longitudinal side member of said pair of said secondary frame, a second screw shaft at one end operatively connected to said second motor means and extending forwardly therefrom longitudinally of said secondary and tertiary frames, a second screw block carried by one longitudinal side member of said tertiary frame and receiving a forward end portion of said second screw shaft therein for moving said tertiary frame longitudinally back and forth with respect to said secondary frame, electrical control means for automatically progressively actuating said first and second motor means forwardly and then backwardly to, in sequence, forwardly advance said secondary and tertiary frames and to, in sequence, backwardly retract them to move said truing head in a full cycle continuous encircling path along the door sealing flange, said control means having switch means for automatically stopping movement of said secondary and tertiary frames on completion of the full cycle path of movement, and said control means having manual means for stopping the automatic progression of said frames at any selected position of their movements and for then thereat reinitiating their automatic progression to continue the truing operation.