Machine for automatically duplicating flat keys

A machine for automatically duplicating flat keys, comprising:

• a. a fixed frame, a movable support having a top portion and being hinged to said frame for movement about a horizontal axis, two sets of jaw means mounted in parallel relationship on said top portion of said movable support for clamping respectively, a model key and a key blank, a feeler carried by said frame engageable by said model key, a motor, a cutter operable by said motor and disposed on said frame having an axis which lies in the median longitudinal plane of the key blank for engagement of the blank by the cutter, two control cam means jointly rotatable for moving said movable support from a departure position to an end position, in respective coordinated reciprocating movements namely a first movement in a direction at least approximately parallel to the axis of said cutter with rapid travel of said support towards said departure position while said model key and said key blank are respectively below said feeler and below said cutter, and with slow travel in the opposite direction during a milling operation, and a second movement in a direction perpendicular to said cutter axis to bring said model key against said feeler and said key blank against said cutter during the milling operation;
• b. parallelogram-like linkage means movable by said control cam means to perform said coordinated movements of said movable support about said horizontal axis and for guiding said movable support in said coordinated movements, comprising a link and a longitudinally extensible rod unit, said link and rod unit being pivotally mounted respectively, about relatively spaced axes on said frame to cause said movable support by rotation of said link in one direction to move perpendicularly to the axis of said cutter in a disengaging direction, and by longitudinal extension of said rod unit, to move parallel to the axis of said cutter in the direction corresponding to its slow travel;
• and
• c. spring return means for resiliently biasing said movable support against both of said two control cam means while they move said linkage means to move said movable support in said slow travel of the first movement and said rapid travel of the second movement, said spring return means being arranged obliquely to the directions of said first and second movements and being interposed between said frame and said movable support for biasing said support towards said departure position.