Out of round tool bit holder assembly
View Patent ↗A tool slide assembly mounted on a clamshell lathe where the clamshell lathe is used to machine an out-of-round work piece. The tool slide assembly generally comprises a base mounted on the rotatable ring of the clamshell lathe and a tool bit holder. The tool bit holder comprises a follower member and a tool block adapted to hold a tool bit, where the follower member is urged against an outer surface of the out-of-round work piece by a plurality of springs. The tool block is incrementally translated such that the tool bit gets fed into the out-of-round work piece.
1. In a clamshell lathe assembly for machining a work piece, the clamshell lathe assembly including a rotatable ring operatively coupled to a stationary ring, the rotatable ring carrying a tool bit for machining a work piece, wherein the improvement comprises:
(a) a tool slide assembly comprising a base and tool bit holder slidably mounted on the base for holding the tool bit where said base is adapted to be mounted on the face of the rotatable ring;
(b) a follower assembly operatively coupled to the tool bit holder for following a contour of an outer surface of the work piece as the tool bit is rotated about said outer surface, said follower assembly including at least one roller operatively coupled to a slide plate where a plurality of springs operatively disposed between the slide plate and the base urge the rollers against the outer surface of the work piece; and
(c) the tool bit holder further including a tool block capable of incremental translation upon orbiting at the rotatable ring.
2. The clamshell lathe in claim 1 wherein in the base has a plurality of apertures for bolting the base to the face of the rotatable ring.
3. The clamshell lathe in claim 1 wherein the slide plate has a midline groove for receiving a threaded feed screw therein, the feed screw carrying a feed nut that cooperates with the tool block.
4. The clamshell lathe assembly in claim 3 here the tool block is translated along the slide plate by rotation of the threaded feed screw.
5. The clamshell lathe in claim 3 where the threaded feed screw is supported by a feed screw bracket mounted on the tool bit holder and the feed nut is mounted on a bottom surface of the tool block.
6. The clamshell lathe in claim 3 where the threaded feed screw further includes a starwheel for turning the threaded feed screw upon a predetermined rotation of the rotatable ring.
7. The clamshell lathe assembly in claim 1 wherein the plurality of springs are supported by a plurality of spring linkage rods that extend through first and second spring brackets to first and second rocker links, said first and second rocker being pivotally connected to the tool bit holder.
8. The clamshell lathe assembly in claim 7 where the first and second rocker links individually pivot on a first and second shoulder screws extending through a midpoint of the first and second rocker links into the tool bit holder.
9. The clamshell lathe assembly in claim 7 where the spring linkage rods are attached to the first and second rocker links by dowel pins extending through a clevis affixed to an end of the spring linkage rods and the first and second rocker links.
10. The clamshell lathe assembly in claim 1 where the tension of the plurality of springs is adjustable.
11. The clamshell lathe assembly in claim 1 where the tool block comprises base member and a top cap for capturing the tool bit in the tool block.
12. The clamshell lathe in claim 10 wherein the linkage rods are threaded and carry a hex nut thereon, rotation of the hex nuts varying the spring tension of the plurality of springs.