Pattern controlled milling machine with a pantograph and a line scanner

Claim 1

In a pattern controlled machine tool, such as a milling machine, of the type that includes (A) a pantograph carrying, at its free end, a tracer point in contact with a pattern and (B) a mechanism for a line-by-line scanning of said pattern and for cutting a workpiece accordingly, said mechanism includes a slider being linearly movable adjacent pattern support means, the improvement comprising, A. a guide lever, B. a handle attached to a first end of said guide lever; said handle being manually engageable to impart a manual force to said guide lever, C. pivot means securing a second end of said guide lever to said slider and permitting a swinging motion of said guide lever about two axes mutually perpendicular with respect to one another and normal to the direction of motion of said slide and D. ball joint means for angularly movably attaching said free end of said pantograph and said tracer point to said guide lever at a location between said first and second ends thereof; substantially the entire length of said guide lever constituting a power arm and the guide lever portion between said pivot means defined in (C) and said ball joint means defined in (D) constituting a load arm.