Duplicating apparatus with variable scale factor

#The invention relates to power tools and specifically to duplicating apparatus utilizing a router for producing a work piece which has a geometric shape which is the same as or smaller than a master object. The prior art includes apparatus which is sold commercially by Sears, Roebuck and Company, Chicago, Ill. Such apparatus is identified as a "router crafter". This apparatus is capable of cooperating with a two dimensional master object to produce a three dimensional work piece. A disadvantage of this apparatus is that the possible geometric shapes of the work piece are severely limited. Another difficulty with such apparatus is that the apparatus which is presently available does not permit variation in the scale between the master object and the work piece.

#It is an object of the invention to provide apparatus which will generate very complex geometric forms such as the "Queen Anne's" furniture legs.

#It is another object of the invention to provide such apparatus which will be simple and inexpensive to construct.

#The invention will be better understood by reference to the accompanying drawing in which:

#FIG. 1 is a simplified partially schematic side elevational view of the apparatus in accordance with one form of the invention;

#FIG. 2 is a simplified partially schematic exploded perspective view of the apparatus shown in FIG. 1; and

#Referring now to FIGS. 1 and 2 there is shown a pivot member 10 on which is carried a router 12. The pivot member 10 includes journal bearings 14 which cooperate with a bar 16 which is carried by end frames 18 and 20. The router 12 includes a blade 21 which extends through a hole 22 in the pivot member 10. The blade 21 cooperates with a work piece 24 which is carried by drive spindle 26 and spindle 29. The end frames 18 and 20 are rigidly connected together by bars 16, 28, 30, and 32. A master object 34 which ordinarily will have three dimensional characteristics to utilize the full capabilities of the apparatus in accordance with the invention is carried between spindle 36 and spindle 38. The spindle 36 is mounted by means of bushing 40 and nut 42. Similarly the spindle 38 is mounted with nuts 44, 44. These spindles are respectively carried on mounting members 46, 48 which each have an elongated slot 50 for carrying the respective spindles. Each mounting member 46, 48 has bores cooperating with bars 32 and 30.

#The mounting for drive spindle 26 includes a handle 60 which cooperates with a drive member 62 which is carried for rotation in end frame 20. The drive member 62 is provided with a cable 64 which encircles the drive member 62 and which also passes over pulleys 66, 68. Rotation of the handle 60 will cause the pivoting member 10 (which may be connected thereto) to translate along the bar 16 so that essentially the entire axial extent of the work piece 24 may be cut by the blade 21 if a clutch mechanism (not shown) in drive member 62 is engaged. Ordinarily the pivoting member 10 will be translated by a force applied directly to the router 12 on pivoting member 10. Rotation of handle 60 will rotate the drive spindle 26 to cause the work piece to rotate. In a similar manner the rotation of the handle 60 will cause the pulley 70 to rotate. Cooperating with the pulley 70 is a belt 72 which also cooperates with a pulley 74 mounted on the spindle 36. Accordingly rotation of the handle 60 also rotates the master object by means of the spindle 36. A belt tensioning member 76 is secured in place by means of nut 42 to insure that adequate tension is maintained on belt 72 so that there is a positive drive between pulleys 70 and 74.

#In some forms of the invention the belt tensioning member will be eliminated and belt 72 will be elastic.