Cutting by use of rotating axially moving tool – With work-engaging structure other than tool or tool-support – Movable relative to tool along tool-axis
Reexamination Certificate
2002-07-03
2003-07-29
Howell, Daniel W. (Department: 3722)
Cutting by use of rotating axially moving tool
With work-engaging structure other than tool or tool-support
Movable relative to tool along tool-axis
C408S11500B
Reexamination Certificate
active
06599064
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for drilling holes, and more particularly, for drilling dowel holes for joining one workpiece to another using, for example, dowels, and for drilling pocket holes for fastening one workpiece to another using, for example, screws.
Traditionally, the drilling of dowel holes and pocket holes has been accomplished with either a jig or a large piece of machinery. The jig, while economical, is time-consuming to set up and use, and often lacks accuracy. Large machinery is suitable for large production job shops but is too expensive and too bulky for a carpenter, a small job shop, or a do-it-yourself woodworker. The invention disclosed addresses the needs of, although not limited to, the carpenter, small job shop, or do-it-yourself woodworker.
Dowel joinery is a very old process and some attempts have been made to mechanize the creation of the dowel hole with limited success. One example of a jig to hold the workpiece appears in U.S. Pat. No. 4,594,032. This jig clamps to the workpiece, possibly causing damage to softer woods, and allows for a very limited number of dowel sizes and workpiece thicknesses. Another example of a jig that holds the workpiece and a powered drill appears in U.S. Pat. No. 4,235,565. This jig is time-consuming to set up for each change of workpiece thickness and requires that it be attached to a bench or table before using it. The present invention does not clamp to the workpiece, so has little chance of damaging it, will support any standard or custom size dowel up to about one inch in diameter, and any workpiece thickness. The present invention is hand-held and portable, so it is easily moved from one drilling operation to the next.
Pocket-hole joinery is a more recent process (reference U.S. Pat. No. 3,496,974) and the jigs developed have mirrored those of the dowel joinery process. One example of a jig to guide a stepped drill bit appears in U.S Pat. No. 5,781,835. The workpiece is clamped in the jig, which can possibly damage the workpiece, the thickness of the workpiece is limited, and it is awkward to use with large workpieces. An example of a powered tool that mechanizes part of the process appears in U.S. Pat. No. 5,375,636. It is a semi-production machine that, in the preferred embodiment, is meant to be mounted to a bench or table. It addresses many of the drawbacks of a jig, but still requires a separate powered hand drill to make the pilot hole cut. The present invention does not clamp to the workpiece, so has little chance of damaging it, and will handle workpieces from about one-half inch to about one and one-half inches thick. The preferred embodiment of the present invention cuts both the bore and pilot hole in one operation and doesn't require any additional steps or equipment to cut a pocket hole.
There is prior art for jigs that guide a drill bit and jigs that guide a portable hand drill, but a dedicated, hand-held, portable, powered drill for creating dowel holes does not currently exist. Similarly, there is prior art for jigs that guide a stepped, pocket-hole drill bit and large, production-sized machines for creating pocket holes, but a dedicated, hand-held,, portable, powered drill for creating pocket holes does not currently exist. The present invention performs the task of drilling both dowel holes and pocket holes and provides the accuracy, versatility, and convenience of use that users desire.
The idea for the present invention came about after building a slatted table top with breadboard ends. The slats were narrow, so each slat had to be joined to the breadboard ends with a dowel joint. The holes for the dowels had to be precisely placed so that all of the workpieces were coplanar once the joints were assembled. This required the use of a doweling jig. The jig was supposed to clamp to the end of the board and guide the drill bit, but because the slats were so narrow, the jig kept slipping off the workpiece making the dowel holes difficult to cut. I envisioned a device somewhat similar to a biscuit cutter or plate jointer, as disclosed in U.S. Pat. No. 4,913,204 to Moores et al., such that a fence would be used to position the device to the workpiece and a plunging motion of the motor and drill bit with respect to the base and fence assembly would produce an accurate dowel hole. However, such a dedicated device would not be economically feasible.
Another project brought up the need to join several workpieces together using a pocket-hole joint. Again, this required a jig to hold the workpiece while the user drilled pocket holes in the workpiece. The choices were either inexpensive jigs that required a lot of setup for each pocket hole, or a relatively expensive jig that reduced the setup time somewhat. Both had the same drawback, as does the doweling jig, that the jig needed to be clamped to the workpiece, which can mar softwoods.
The solution was to take my original idea and give it the ability to drill oblique holes for pocket-hole joints. This device would be able to drill dowel holes quickly, accurately and with very little setup time and, by tilting the motor and drill bit assembly with respect to the base, would be able to drill pocket holes quickly, accurately and with very little setup time. Since my upper and lower fences rest against the workpiece without gripping, to cut either type of hole, it can't mar softwoods. My dual-purpose device is easy to move around the workshop, the workpiece can be brought to the device to cut the holes, or the device can be brought to the workpiece whether it's on the bench or at the work site. This combination dowel hole and pocket hole drill would be economically feasible.
Marring of softwood workpieces also can be produced by hold-down devices. Mastley patent, 6,374,878, utilizes such hold-down members that are “pressed against the workpiece to keep the workpiece from moving upward.” (upon retraction of the drill after the hole is formed); see col. 3, lines 50-60. Such members can make undesirable indentations in soft woods, like the aforesaid gripping action. While Raines 4,842,453 does not require a workpiece clamp or mar producing hold-down device pushing against the softwood workpiece, the fixture holding the workpiece has to be held down to keep it from moving about during the drilling operation. The need to hold the fixture against a support table is eliminated by the present invention. Also, the support table 40 of Raines tilts back to accommodate thicker workpieces. Ideally, the angle of the workpiece to the pocket-hole drill bit should be around 15 degrees. By tilting the support table 40 back, the angle of the workpiece to the drill bit increases substantially. This increases the difficulty in keeping the two workpieces coplanar during assembly. This device was meant to work primarily with ¾ inch thick workpieces.
SUMMARY OF PREFERRED EMBODIMENTS OF THE INVENTION
The present invention provides a single apparatus enabling a user to drill accurate, repeatable dowel holes in an expeditious manner. Further, the present invention provides the ability to drill accurate, repeatable pocket holes in an expeditious manner with such a single apparatus without the need for the user to perform tedious, time consuming, error prone calculations.
An object of the present invention is to provide a portable hand-held drilling machine that is easily carried from place to place by the operator.
Another object of the present invention is to provide a simple and quick means to create a dowel-hole joint that can be secured with a wooden dowel.
Another object of the present invention is to provide a first fence for the purpose of accurate alignment and placement of the tool to the workpiece prior to drilling the dowel hole. A further object of the present invention is to provide an accurate graduated indicator for proper placement of the fence prior to drilling the dowel hole.
Another object of the present invention is to provide a simple and quick means to create a pocket-hole joint in addition to the dowe
Howell Daniel W.
Nathans Robert
LandOfFree
Combined dowel-hole and pocket-hole drilling apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Combined dowel-hole and pocket-hole drilling apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Combined dowel-hole and pocket-hole drilling apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3053501