Note: Descriptions are shown in the official language in which they were submitted.
CA 02539739 2006-03-15
JOINT DEVICE FOR WOOD-HANDLED WOODTURNING TOOLS
FIELD OF THE INVENTION
The present invention relates to the field of wood turning.
BACKGROUND OF THE INVENTION
In the field of wood turning, various tools, such as bowl gouges and spindle
gouges, are
used for shaping wood.
Historically, woodturning tools included a wooden handle having a recess
defined
therein at one end; a metal wood-cutting bit fitted in and extending from the
recess; and
a ferrule fitted around the handle, overlying the recess, to strengthen the
end of the
handle and prevent splitting therein.
It is known for wood turners to self-manufacture woodturning tools, by
assembling
purchased wood-cutting bits and purchased ferrules with self-manufactured
handles.
This reduces cost to the wood turner, and permits the wood turner to self-
manufacture a
handle that is customized in terms of shape and wood to his or her liking.
However,
proper application of a ferrule to a wooden handle is not an easy task, and is
typically
facilitated by the use of specialized ferrule clamping equipment, which is not
always
readily available to wood turners.
Accordingly, specialized handles have been developed, which releasably,
securely
receive wood-cutting bits. One known handle of this type includes a handpiece
having
a recess at one end. The recess is adapted to receive a wood-cutting bit, such
as a
spindle gouge or bowl gouge, such that the wood-cutting bit projects from the
recess.
In the handle, a pair of threaded bores are provided, in which are threaded
conventional
set screws. In use, a wood-cutting bit is fitted in the recess, and the set
screws are
engaged, to bear against the wood-cutting bit and releasably secure same in
position.
This fastening mechanism enables bits to be easily replaced.
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These specialized handles render it possible for the wood turner to avoid the
costs
associated with the purchase of wooden handles and the procurement of
specialized
ferrule clamping tools. However, these specialized handles are relatively
costly, and
providing same in a wide variety of shapes and sizes, to meet the specific
desires of
individual wood turners, would add even further to costs.
SUMMARY OF THE INVENTION
A device for use with a bit and a wooden handle forms one aspect of the
invention.
The bit and handle with which this device is used have respective ends. This
device
comprises a body. The body defines a first recess, a second recess and at
least one
threaded bore. The first recess receives the end of the bit in use. The second
recess
securely receives the end of the handle in use. The at least one threaded bore
extends
from the first recess through the body. This device further comprises a set
screw for
each threaded bore and threadably engaged therein, in use, to bear against the
bit and
releasably lock the bit in the first recess, to form a hand tool.
A device for use with an elongate wood-cutting bit and an elongate wooden
handle
forms another aspect of the invention. The bit and handle with which this
device is used
have respective ends. This device comprises a body. The body defines a first
recess,
a second recess and at least one threaded bore. The first recess receives the
end of
the wood-cutting bit in use. The second recess securely receives the end of
the handle
in use. The at least one threaded bore extends from the first recess through
said body.
This device further comprises a set screw for each threaded bore and
threadably
engaged therein, in use, to bear against the bit and releasably lock the bit
in the first
recess, to form a wood-turning tool.
A device for use with an elongate wood-cutting bit and an elongate wooden
handle
forms another aspect of the invention. The bit with which this device is used
has a
shank portion and a cutting portion. The handle with which this device is used
has a
handpiece and a frustoconical end. This device comprises a body defining a
first
recess, a second recess and at least one threaded bore. The first recess
receives the
shank portion of the wood-cutting bit in use. The second recess securely
receives the
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end of the handle in use. The at least one threaded bore extends from the
first recess
through the body. This device further comprises a set screw for each threaded
bore
and threadably engaged therein, in use, to bear against the bit and releasably
lock the
bit in the first recess, to form a wood-turning tool.
These devices permit a wood turner to relatively inexpensively self-
manufacture a hand
tool, having a turned handle that is customized in terms of shape and wood to
his or her
liking, without the need to press-fit a ferrule. Other advantages, features
and
characteristics of the present invention, as well as methods of operation and
functions
of the related elements of the structure, and the combination of parts and
economies of
manufacture, will become more apparent upon consideration of the following
detailed
description and the appended claims with reference to the accompanying
drawings, the
latter being briefly described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a perspective view of a joint device according to a first
preferred
embodiment of the invention;
FIGURE 2 is a perspective view of the device of FIGURE 1 in use;
FIGURE 3 is a front elevational view of the device of FIGURE 1;
FIGURE 4 is a longitudinal cross-section of the device of FIGURE 1;
FIGURE 5 is a rear elevational view of the device of FIGURE 1;
FIGURE 6 is a front elevational view of a joint device according to a second
preferred
embodiment of the invention;
FIGURE 7 is a longitudinal cross-section of the device of FIGURE 6;
FIGURE 8 is a rear elevational view of the device of FIGURE 6;
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FIGURE 9 is a front elevational view of a joint device according to a third
preferred
embodiment of the invention;
FIGURE 10 is a longitudinal cross-section of the device of FIGURE 9;
FIGURE 11 is a rear elevational view of the device of FIGURE 9;
FIGURE 12 is a front elevational view of a joint device according to a fourth
preferred
embodiment of the invention;
FIGURE 13 is a longitudinal cross-section of the device of FIGURE 12; and
FIGURE 14 is a rear elevational view of the device of FIGURE 12.
DETAILED DESCRIPTION
With reference to FIGURE 1, a preferred embodiment of the present invention, a
joint
device, is illustrated and is designated by the general reference numeral 20.
The device is shown in use in FIGURE 2 with an elongate wood-cutting bit 22
and a
wooden handle 24. The wooden handle 24 has a handpiece 26 and a frustoconical
end
(not shown). The wood-cutting bit 22 is a gouge, and has a shank portion 28
and a
cutting flute portion 30.
With reference to FIGURE 1 through FIGURE 5, the device 20 comprises a brass
body
32 and a pair of set screws 34.
The body 32 defines a first cylindrical recess 36, a second frustoconical
recess 38 and
at least one threaded bore, specifically, two threaded bores 40, each
extending from the
first recess 36 through the body 32. The first recess 36 and second recess 38
are
substantially coaxial, and the bores 40 are axially spaced from one another.
The body
32 defines an interior thread 44 surrounding the second recess 38,
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In use, as shown in FIGURE 2, the first recess 36 receives the shank portion
28 of the
wood-cutting bit 22, the frustoconical end of the handle 24 is disposed in the
second
recess 38 and securely received by the body 32, by engagement of the thread
44, and
the set screws 34 are threadably engaged in the bores 40 to bear against the
bit 22 and
releasably lock the bit 22 in said first recess 36, to form a wood-turning
tool, specifically,
a bowl gouge, indicated generally with reference numeral 42 in FIGURE 2.
So as to provide a tight, secure fit between the handle 24 and the device 20,
the
frustoconical end of handle 24 is preferably shaped so as to taper at the same
rate as
the thread 44, with a widest end of the frustocone being slightly larger than
the minor
diameter of the thread 44 at thread start, and the length of the frustocone
being about
the length of the thread 44 or the recess 38, whichever is longer.
The structure illustrated in FIGURE 1 - FIGURE 5 is a 5/8" device, that is a
device
intended for use with 5/8" OD bits. FIGURE 6- FIGURE 8 show a'h" device.
FIGURE 9- FIGURE 11 show a 3/8" device. FIGURES 12-14 show a'/a" device.
Structures in FIGURES 6-14 corresponding to structures shown in FIGURES 1-5
are
identified with the same number.
It is notable that the structures of FIGURE 9- FIGURE 14 include only a single
threaded bore 40, since duplicate bores 40 are not necessary for these
devices.
Otherwise, the structures of FIGURES 6-14 are substantially functionally and
structurally substantially identical to the structure of FIGURES 1-5, and no
further
description thereof is viewed as necessary.
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Various specifications for these devices are set forth below:
Bit size (OD) 5/8" '/2'3/8" '/a"
Device length 3" 2.75" 2.5" 2.25"
Thread length 1.31 1.26" 1.16" 1.06"
Bit recess I D .64" .515" .39" .265"
Thread 1 3/16 10 TPI 1 1/16 10 TPI 15/16 10 TPI 7/8 10 TPI
tapered 4 start tapered 4 start tapered 4 start tapered 4 start
included angle included angle included angle included angle
2.60 2.60 2.60 2.60
Maj. Dia. At 1.180" 1.062" .927" .865"
Thread Start
Major Dia. At 1.132" 1.014" .884" .816"
Thread End
Minor Dia. At 1.150" 1.032" .897" .835"
Thread Start
Minor Dia. At 1.092" 0.984" .874" .786"
Thread End
Number of 2 2" 1 1
bores
Bore s acin .63" .5" NA NA
It is to be understood that while but four embodiments of the present
invention have
been herein shown and described, it will be understood that various changes in
size
and shape of parts may be made. For example, whereas the joint devices herein
are
described to be brass, other materials, such as aluminum, could be utilized.
As well,
whereas the devices herein are shown to form a bowl gouge, it will be evident
that the
use of a different bit would produce a different tool. By way of example,
only, spindle
gouges could equally be formed. As well, whereas various sizes, dimensions and
thread arrangements are specified, other sizes, dimensioned and thread
arrangements
can be utilized. For example, the handle from which the tools described herein
are
produced is indicated to have a frustoconical end, into which end the device
thread cuts
during assembly. It is equally possible to utilize a handle with a pre-cut
thread, in which
event it may be desirable to modify the pitch, spacing and/or shape of the
thread
surrounding the second recess. Accordingly, the invention should be understood
as
limited only by the claims appended hereto, purposively construed.
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