Three-dimensional apparatus for a router for producing copies variations of templates

A three-dimensional apparatus for a router for positioning and guiding the router to produce, from a workpiece, at least one of a substantial duplicate of a three-dimensional configuration of a template and a substantial variation of such three-dimensional configuration of such template by routing such workpiece. The three-dimensional apparatus for a router including a workpiece mounting platform for mounting the workpiece, a template mounting platform for mounting the template, a router mounting platform for mounting the router, a router positioning mechanism for positioning the router mounting platform adjacent to the workpiece mounting platform, a probe for tracing the three-dimensional configuration of the template and a linkage interconnecting the probe and the router mounting platform to move the router mounting platform in response to movement of the probe. The router positioning mechanism including a three-dimensional movement mechanism for permitting movement of the router mounting platform in each of three mutually orthogonal directions.

FIELD OF THE INVENTION 
The present invention relates, in general, to woodworking equipment and, 
more particularly, this invention relates to an apparatus for use with a 
widely available router to permit the router to readily and accurately 
duplicate a three-dimensional contour of an object, for example, a 
template. 
BACKGROUND OF THE INVENTION 
As is generally well known in the prior art, routers are in widespread use 
among carpenters, craftspeople and generally anyone involved in 
woodworking. 
Frequently, a craftsperson (e.g., a woodworker) wishes to duplicate a 
contour of an existing object so as to reproduce any of a number of 
already existing decorative or utilitarian designs in wood and/or other 
materials. 
Alternatively, a craftsperson may wish to produce repeated copies of a 
particular three-dimensional design which may be embodied in a template. 
OBJECTS OF THE INVENTION 
It is, therefore, one of the primary objects of the present invention to 
provide a three-dimensional apparatus for a router which allows the router 
to be utilized in a manner that will enable a more accurate reproduction 
of a three-dimensional contour of an existing object, for example, a 
template or an already existing design. 
Another object of the present invention is to provide a three-dimensional 
apparatus which allows the router to produce, working from an existing 
template, three-dimensional designs in a workpiece which are substantial 
variations on the three-dimensional design embodied in the template. 
A further object of the present invention is to provide an apparatus which 
is relatively simple in design and rather rugged in construction and, 
therefore, inexpensive to manufacture and durable in use. 
In addition to the objects and advantages of the present invention 
described above, various other objects and advantages of the invention 
will become more readily apparent to those persons skilled in the relevant 
art from the following more detailed description of the invention, 
particularly, when such description is taken in conjunction with the 
attached drawing Figures and with the appended claims. 
SUMMARY OF THE INVENTION 
In one aspect, the invention features a three-dimensional apparatus for a 
router for positioning and guiding a router to produce, from a workpiece, 
at least one of a substantial duplicate of a three-dimensional 
configuration of a template and a substantial variation of such 
three-dimensional configuration of such template by routing a workpiece. 
The three-dimensional apparatus for a router includes a workpiece mounting 
platform for mounting the workpiece, a template mounting platform for 
mounting the template, a router mounting platform for mounting the router 
and a router positioning mechanism for positioning the router mounting 
platform adjacent the workpiece mounting platform. A probe is provided for 
tracing the three-dimensional configuration of the template and a linkage 
interconnects the probe and the router mounting platform to move the 
router mounting platform in response to movement of the probe. The router 
positioning mechanism includes a three-dimensional movement mechanism for 
permitting movement of the router mounting platform in each of three 
mutually orthogonal directions. 
In another aspect, the invention generally features a three-dimensional 
milling apparatus for mounting a milling tool and for producing, in a 
workpiece, at least one of a substantial reproduction of a template and a 
substantial variation of the template when the template extends along 
three separate and independent axes. The milling apparatus includes at 
least one template platform for mounting the template in a template 
position, a workpiece platform for mounting the workpiece in a workpiece 
position and a milling tool support structure for mounting the milling 
tool in a milling tool position. A probe is provided for determining a 
surface of the workpiece with respect to the workpiece position and a 
linkage mechanism determines the milling tool position in response to the 
determined surface of the workpiece. The template has three separate and 
independent axes and the linkage means is effective to alter the milling 
tool position in each of the three separate and independent axes with 
respect to a position of the probe.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Prior to proceeding to the more detailed description of the invention, it 
should be noted that identical components having identical functions have 
been identified with identical reference numerals throughout the several 
views illustrated in the drawing Figures. 
Referring to FIGS. 1 and 2, a router apparatus adapted for the reproduction 
of a three-dimensional contour of an object is generally designated by 
reference numeral 10. An object which already embodies the 
three-dimensional contour which it is desired to duplicate is generally 
referred to herein as a "template" and is indicated by reference numeral 
12. 
While the term "template" is used herein, such term should not be 
understood to limit the invention to the reproduction only of so-called 
templates. The invention can be readily used to reproduce a 
three-dimensional contour of a wide range of existing objects, for 
example, to duplicate a molding or filigree design in carpentry, etc. 
The design is to be duplicated from the template 12 into a workpiece 14, 
the work being performed by a router, the router being shown generally in 
phantom and designated by reference numeral 16. 
The router apparatus 10 generally includes a workpiece mounting platform 18 
for mounting the workpiece 14, a template mounting platform 20 for 
mounting the template 12 and a router mounting platform 22 for mounting 
the router 16. The router 16 is positioned adjacent the workpiece 14 and, 
preferably, is suspended over the workpiece 14 by a router positioning 
mechanism 24. 
As will be explained more fully below, the router positioning mechanism 24, 
in combination with a counterbalancing mechanism described herein, is 
effective to permit the router mounting platform 22 and the router 16 
mounted thereon to be moved simultaneously through three mutually 
orthogonal axes, e.g., the x, y and z axes, while additionally supporting 
the weight of the router mounting platform 22 and the router 16 mounted 
thereupon, thereby relieving the operator of the router apparatus 10 from 
supporting such combined weight and allowing for a more controlled and 
dexterous sculpting of the workpiece 14. 
A probe 26 is provided for contacting and tracing (i.e., moving over) a 
three-dimensional contour of the workpiece 14 and a linkage mechanism 
connects the probe 26 to the router mounting platform 22 so as to cause 
the router mounting platform 22 to move in response to movement of the 
probe 26 as it traces the three-dimensional contour of the workpiece 14. 
Preferably, as shown in FIGS. 1 and 2, such a linkage mechanism is 
provided in the form of a rigid offset arm 28 which extends outward from 
the router mounting platform 22. Additionally, in order to allow for a 
rapid switching between different templates, the router apparatus 10 
preferably includes a second template mounting platform 30 and a second 
probe 32 positioned thereover by an additional offset arm 34 extending 
outward from the router mounting platform 22. 
The router positioning mechanism 24 permits simultaneous movement of the 
router mounting platform 22 in three different directions by providing a 
vertical translation mechanism 36, a first horizontal translation 
mechanism 38 and a second horizontal translation mechanism 40. The first 
horizontal translation mechanism 38 and the second horizontal translation 
mechanism 40 permit movement of the router mounting platform 22 along 
horizontal axes which are substantially perpendicular to one another and 
the vertical translation mechanism 36 provides movement of the router 
platform 22 along an axis which is substantially perpendicular to both of 
the horizontal movement axes provided by the first and second horizontal 
translation mechanisms 38 and 40. 
Thus, it should be readily apparent that the presently preferred router 
positioning mechanism 24 permits substantially simultaneous movement of 
the router mounting platform 22 in each of these three mutually orthogonal 
directions, i.e., a vertical direction and two mutually perpendicular 
horizontal directions. 
The vertical, first horizontal and second horizontal translation mechanisms 
36, 38 and 40, respectively, are preferably provided as slide block 
bearing assemblies. To this end, the router apparatus 10 includes a base 
member 46 of generally oblong shape and having four vertical shafts 48 
projecting vertically upward from the four corners thereof. Such router 
mounting platform 22 is mounted on a vertically translatable subassembly 
50 which includes the router mounting platform 22, the first and second 
horizontal translation mechanisms 38 and 40 and at least four vertical 
bearings 52. 
One each of the four vertical bearings 52 slidingly engages one each of the 
four vertical shafts 48, thereby permitting the vertically translatable 
subassembly 50 to move vertically with respect to the base member 46 and 
the four vertical shafts 48. Preferably, the vertical bearings 52 are 
provided as slide block bearings which substantially surround and 
slidingly engage the vertical shafts 48. 
In order to implement the first horizontal translation mechanism 38, the 
vertically translatable subassembly 50 further includes four bracket 
members 54, one each of which extends outward from one each of the 
vertical bearings 52 and a first set of horizontal shafts 56 which extend 
between respective pairs of the bracket members 54 on opposite sides of 
the workpiece mounting platform 18. 
A first set of horizontal bearings 58 slidingly engage the first set of 
horizontal shafts 56 to thereby permit the router mounting platform 22 
(and the probe 26 linked thereto by the offset arm 28) to move in a first 
horizontal direction with respect to the base member 46, with respect to 
the workpiece mounting platform 18 and with respect to the template 
mounting platform 20. The first set of horizontal bearings 58 are also 
preferably provided in the form of slide block bearings which surround and 
slidingly engage the first set of horizontal shafts 56. 
The second horizontal translation mechanism 40 of the router positioning 
mechanism 24 is preferably implemented by providing the router apparatus 
10 with a second set of horizontal shafts 60 that are connected to the 
first set of horizontal bearings 58 through a pair of flange members 62. 
Each of the flange members 62 is connected to and extends horizontally 
from one each of the first set of horizontal bearings 58 and the second 
set of horizontal shafts 60 are aligned in parallel and extend at 
substantially right angles to the first set of horizontal shafts 56. A 
second set of horizontal bearings 64 slidingly engage the second set of 
horizontal shafts 60 and the second set of horizontal bearings 64 are 
connected, e.g., by welding or other suitable means, to the router 
mounting platform 22. Again, preferably, the second set of horizontal 
bearings 64 are of the slide block type. 
In the presently preferred embodiment, the second set of horizontal shafts 
60 are positioned vertically above the first set of horizontal shafts 56. 
Through the provision of each of the vertical translation mechanism 36, the 
first horizontal translation mechanism 38 and the second horizontal 
translation mechanism 40 as described above, the router mounting platform 
22 and the probe 26 linked thereto are enabled for simultaneous movement 
in each of three mutually orthogonal directions. 
Since commercially available routers may be of considerable weight and in 
order to reduce the strain on the operator, the router apparatus 10 
additionally preferably includes a counterbalancing mechanism 66 for 
counterbalancing the combined weight of the router mounting platform 22 
and any router 16 mounted thereon. Such counterbalancing mechanism 
includes a biasing element 68 for resiliently urging the router mounting 
platform 22 in an upwardly direction. Preferably, the biasing element 68 
is provided in the form of an elongated coil spring 70. However, it will 
be apparent that other elastic elements can be substituted therefor. 
In addition, various placements and configurations of the biasing element 
68 can be imagined. For example, the biasing element 68 could be 
configured as an extensible coil spring surrounding any or all of the 
vertical shafts 48 and connected to the vertically translatable 
subassembly 50 so as to be put in tension under the weight of such 
vertically translatable subassembly 50. Alternatively, the biasing element 
68 could be configured as a compressible coil spring surrounding any or 
all of the vertical shafts 48 and be positioned beneath the vertical 
bearings 52 so as to be compressed by the weight of the vertically 
translatable subassembly 50. 
However, the present inventor has discovered that, in either of these or 
similar configurations, the resulting upward force exerted by the biasing 
element 68 is not as "linear" with respect to displacement as could be 
desired. Further, it has been discovered that a configuration utilizing a 
more elongated biasing element 68 produces a more desirable result. 
To this end, the elongated coil spring 70 is extended over at least one, 
and preferably two, supporting members 72 which are positioned above the 
vertically translatable subassembly 50. The supporting members are 
preferably provided as pulleys 74 which are rotatably mounted on cross 
members, preferably in the form of spindles 76, extending between pairs of 
the vertical shafts 48 on opposite sides of and outward of the router 
mounting platform 22. The opposing ends of the elongated coil spring 70 
are connected to a pair of end plates 78 which are, in turn, connected to 
the vertically translatable subassembly by their attachment to the four 
vertical bearings 52. The end plates 78, therefore, move with the 
vertically translatable subassembly 50. In the presently preferred 
embodiment, the ends of the coil spring 70 are provided with hooked 
portions 79 which hook over the lower edges of the end plates 78. 
It has been found preferable to utilize, in addition to the four vertical 
bearings 52 already described, two additional vertical bearings 80 (also 
preferably of the slide block type). Each of the two additional vertical 
bearings 80 are slidably mounted on one of the four vertical shafts 48 
above one of the four vertical bearings 52 and are vertically spaced 
therefrom. Thus, preferably, there are three each of the vertical bearings 
52 and 80 that are positioned on each flanking side of the router mounting 
platform 22. A pair of longitudinal bars 82 run lengthwise connecting 
pairs of the vertical shafts 48 and providing an upper travel limit when 
the additional vertical bearings 80 contact the longitudinal bars 82. 
Similarly, bolsters 84 are located at the bases of the vertical shafts 48 
and adjacent the base member 46 to thereby limit the lower travel of the 
vertically translatable subassembly 50 by the contact of the vertical 
bearings 52 therewith. 
A template clamping mechanism 86 is provided for clamping the template 12 
to the template mounting platform 20. In the presently preferred 
embodiment, the template clamping mechanism 86 is provided in the form of 
four threaded template clamping screws 88. A workpiece clamping mechanism 
90 is similarly provided for clamping the workpiece 14 to the workpiece 
mounting platform 18, presently preferred as being in the form of four 
threaded workpiece clamping screws 92. 
Typically, a commercially available router has a base plate which is 
provided with screw holes, etc. to allow the router to be attached to an 
accessory such as a router table. The router mounting platform 22 is 
preferably configured to mate with the base plates of such routers through 
provision of appropriately placed screw holes 94, etc. 
To allow the probe 26 to be conveniently traced over the three-dimensional 
contour of the template 12, each of the offset arms 28 and 34 is provided 
with an upstanding handle 96. 
Preferably, the router 16 is of the so-called "plunge router" type, thereby 
allowing the router bit to be plunged into the workpiece 14 until the 
slack is removed from the plunge mechanism, whereupon the probe 26 is then 
moved down into contact with the template 12. 
FIG. 3 is a detailed enlarged view of a portion of FIG. 2, showing one of 
the first set of horizontal bearings 58, the flange member 62 connected 
thereto and one of the second set of horizontal shafts 60 extending from 
the flange member 62. The horizontal bearings 58, as well as all of the 
remaining slide block type bearings 52, 64 and 80, preferably include a 
pillow block 98 and a "ball binding bearing" 100 positioned within the 
pillow block, the ball binding bearing 100 sliding along the respective 
shaft 48, 56 or 60. 
Applicant has achieved good results utilizing for the pillow blocks 98, 
ball binding bearings 100 and shafts 48, 56 and 60 the following 
components obtained from Thompson Industries, Inc.: 
Pillow Blocks: Part No. SPB16 
Ball Binding Bearings: Part No. B162536 
Shafts: ground and hardened 
In operation, a template 12 positioned in either template mounting platform 
20 or 30 may be substantially duplicated into a workpiece 14 positioned in 
the workpiece mounting platform 18 by tracing the three-dimensional 
contour of the template 12 with the respective probe 26 or 32. In order to 
substantially duplicate the template, substantially the same or a similar 
set of router bits are used as were originally used in producing the 
template 12. 
Additionally, however, the applicant has discovered that new and unusual 
patterns can be produced by fitting the router 16 with a different 
assortment of bits which vary from those used to produce the original 
template. Accordingly, the present invention can also be utilized to 
produce alternative and/or derivative designs by fitting the router 16 
with different sets of bits. 
While the present invention has been described by way of a detailed 
description of a particularly preferred embodiment, it will be readily 
apparent to those of ordinary skill in the art that various substitutions 
of equivalents may be affected without departing from the spirit or scope 
of the invention as set forth in the appended claims.