Wood turning – Turning tools
Reexamination Certificate
1999-09-28
2001-07-03
Bishop, Steven C. (Department: 3722)
Wood turning
Turning tools
C408S227000
Reexamination Certificate
active
06253812
ABSTRACT:
This invention relates to a turning tool for turning wood. It relates more particularly to a hand-held wood turning tool which is especially adapted to form a recess in a turning workpiece of wood.
BACKGROUND OF THE INVENTION
There are a variety of situations where one may want to form a recess in a workpiece. For example, the interior of a wooden goblet has a curved recess. Also, some goblets are designed with a glass parabola which sits in a recess atop a wooden base. Similar wooden bases are used to support bowls and other convex articles of one kind or another.
Conventionally, to form a recess in a workpiece, a cutting tool such as chisels, gougers and scrapers are used to permit relatively rapid rough cutting and scraping followed by a more careful surface finishing in order to form the recess in that article. The various tools are applied against the end of the workpiece which is being turned around its longitudinal axis. Invariably, these tools only engage the turning workpiece with one cutting edge at the downside of the workpiece rotation. Therefore, the user has to repeatedly check the progress of the recess with a template to be sure that it is symmetrical and centered on the turning axis. Needless to say, this makes the turning task somewhat tedious and time consuming.
Therefore, there is a need for a wood turning tool which can form precisely shaped recesses in wooden workpieces more efficiently than has been possible heretofore.
SUMMARY OF THE INVENTION
Accordingly, the present invention aims to provide a wood turning tool for forming a precisely shaped recess in a turning workpiece in a reliable and efficient manner.
Another object of the invention is to provide a turning tool of this type which is capable of cutting a recess in a turning workpiece to a finished form.
Another object of the invention is to require such a turning tool which eliminates the need for a template to check the accuracy of the recess as it is being formed in the workpiece.
A further object of the invention is to provide a wood turning tool whose working end functions as a template for the finished recess.
Other objects of the invention will, in part, be obvious and will, in part, appear hereinafter.
The invention accordingly comprises the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereinafter set forth and the scope of the invention will be indicated in the claims.
Briefly, my turning tool has a front or working end formed as a flat blade of plow-like shape, the apex of the plow coinciding with the central longitudinal elevation or centerline of the blade. The top and bottom surfaces of the blade are flat and generally parallel to one another. By an undercut ground bevel on the front or working edge of the blade on one side of the elevation, a cutting edge is formed at the top surface of the blade. A second cutting edge is present on the opposite side of the elevation at the bottom surface of the blade due to an overcut ground bevel on the working edge of the blade on that side of the elevation.
In use, the tool is placed on a tool rest so that the apex of the plow engages the end of the turning workpiece at the axis of rotation thereof. As the workpiece rotates, the downwardly moving portions of the workpiece are engaged by the cutting edge at the top surface of the blade while the upwardly moving portions of the workpiece are engaged and cut by the cutting edge at the bottom surface of the blade. Thus, the tool removes twice as much material from the turning workpiece as a conventional turning tool with a single cutting edge.
Furthermore, having two cutting edges disposed on opposite sides of the blade apex at the axis of rotation of the workpiece, the tool is self-centering so that the apex of the plow tends to remain at the center of the workpiece. Resultantly, as the tool is advanced into the end of the workpiece, the recess formed by the tool remains symmetrical and centered on the turning axis during the entire turning process. This means that the recess formed in the workpiece will ultimately have the same shape as the tool blade. In other words, the tool itself functions as a template for the recess. By using tools with different plow curvatures, a variety of differently shaped recesses may be formed depending upon the purpose or function of the workpiece.
REFERENCES:
patent: D. 358080 (1995-05-01), Handler
patent: 622461 (1899-04-01), Glardon-Jacquet
patent: 809567 (1906-01-01), Henckel
patent: 2660039 (1953-11-01), Newell
patent: 2914098 (1959-11-01), McLennan
patent: 3014509 (1961-12-01), Cederblad
patent: 3229731 (1966-01-01), Hilton
patent: 3393819 (1968-07-01), Van De Walle
patent: 4754787 (1988-07-01), Smith
patent: 4924924 (1990-05-01), Stewart
patent: 4998572 (1991-03-01), Lukes
patent: 5137065 (1992-08-01), Stewart
patent: 5190418 (1993-03-01), Nakayama et al.
patent: 5295598 (1994-03-01), Gerlach et al.
patent: 5513764 (1996-05-01), Harrison et al.
patent: 5626446 (1997-05-01), Ching
patent: 5682933 (1997-11-01), Martel
patent: 5850860 (1998-12-01), Memelink
The Woodturners Catalog, Craft Supplies USA, p. 23, Oct. 1992.
Bishop Steven C.
Cesari and McKenna
Woodcraft Supply Corp.
LandOfFree
Wood turning tool does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Wood turning tool, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Wood turning tool will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2491208