BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates to emery wheel grinding machine with an adjustable
chuck, and more particularly, to an emery wheel grinding machine equipped with an
adjustable drill bit chuck suitable for shaving the drill bit or a cutter of a two
or more faced and variously lengthed blade of a hobbing cutter other than a single
blade one.
Description of the Related Art
[0002] A conventional portable grinding machine, as it was disclosed and published by Taiwan
Pat. No.
286610,
155338, is composed of a housing, a cap covered at one end thereof, a transmission gearing
equipped in the housing, a emery wheel and guiding members. When it is to be used,
the whole unit is set on an electric motor with the grinding machine coupled with
the main shaft of the electrical drill so as to impart the rotational power of the
electrical drill to the emery wheel with transmission gearing for running. At the
same time, a drill bit or cutter to be shaved is affixed to the machine unit with
the guiding members so as to shave and grind the drill bit or cutter blade to a desired
extent.
[0003] With the grinding machine described above, the grinding or shaving effect can only
reach to the very small part surrounding the central pointed drill head without reaching
further to the portion of the blade edge at the recessed clearance, that greatly degrades
the effect of finishing drill bit.
[0004] For an improvement, the applicator invented an innovative Portable Drill Bit Grinding
Machine which was patented by Taiwan Pat. No.
547228. As shown in Fig. 1, this newly developed apparatus is essentially composed of an
emery wheel 20 driven by a power source associated with a work fixture and a drill
bit fixing means 30 for operation. The work fixture is cooperated with a first grinding
base 40 for the purpose of affixing the blade of the drill bit in such a manner that
its clearance angle is closely fitted to the tilted grinding surface 21 of the emery
wheel 20. Then, the work fixture is cooperated with a second grinding base 50 for
the purpose of affixing the blade of the drill bit in such a manner that its spiral
angle to be closely fitted to the tilted grinding surface 21 of the emery wheel 20.
[0005] As shown in Fig. 1, the drill bit fixing means 30 comprises a work fixture fastening
base 31 for setting the work fixture, and a drill bit fastening jig 32. The work fixture
fastening base 31 is provided with a mounting hole that allows the work fixture to
be engaged in, and a rotation limiting post with a prescribed angle provided at the
circumference of the mounting hole.
[0006] The first grinding base 40 is engaged to a machine housing 10 in front of the emery
wheel 20 aligned in the same center line, and is kept a distance with the emery wheel
20 equal to that between the work fixture fastening base 31 and the drill bit fastening
jig 32. The first grinding base 40 is approximately configured in L shape with an
arcuate sliding slot 41 formed at the base surface thereof. By fastening the arcuate
sliding slot 41 with a bolt 42, the first grinding base 40 can practically keep a
relevant angle with the emery wheel 20 so as to grind and shave a variety of drills
such as standard drill, rugged drill, or ebonite drill having the blades of different
clearance angles and recesses.
[0007] The first grinding base 40 has a vertical wall 46 on which being provided with a
mounting hole 43 for engaging the work fixture therein, and two rotation limiting
posts 44, 45 with a prescribed angle and distance are formed at the circumference
of the mounting hole 43. The mounting hole 43 is upwardly inclined with an angle about
10 ~ 25° in order to fit the direction of the blade of the drill bit to be shaved.
[0008] The second grinding base 50 is engaged to the machine housing 10 with a bolt 51 above
the emery wheel 20 keeping a distance with the latter equal to that between the work
fixture fastening base 31 and the drill bit fastening jig 32. The second grinding
base 50 has a mounting hole 52 for engaging the work fixture therein and a rotation
limiting post 53 with a prescribed angle standing on the circumference of the mounting
hole 52.
[0009] However, the improved portable grinding machine patented by No.
547,228 described above is still having a limited use for grinding conventional drill or cutter
only, it is inapplicable to a particular drill or cutter with two or more blades.
[0010] For these defects noticeable on the prior art, further improvement is seriously required.
The inventor has dedicated great efforts for years to studying and improving these
defects and came up with the present invention to be disclosed herein.
SUMMARY OF THE INVENTION
[0011] The present invention is to provide an emery wheel grinding machine with adjustable
bit chuck which has a tilted T-bushing, and its outer flange is provided with several
stop traps with the number corresponding to that of the blades of a hobbing cutter
to be shaved. On the outer flange of the T-bushing is also provided with two stop
pins for defining the turning angle of the head of the hobbing cutter.
[0012] The tilted T-bushing of the present invention is not only able to adjust the chuck
angle according to the figure and number of blades of the hobbing cutter, but also
can control the turning angle of the hobbing cutter with the stop pins so that the
clearance angles and the recesses between the blades can be effectively shaved.
[0013] The above object and other advantages of the present invention will become more apparent
by describing in detail the preferred embodiments of the present invention with reference
to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014]
FIG. 1 is the three dimensional view of The Portable Drill Bit Grinding Machine Patented
by Taiwan Pat. No. 547,228;
FIG. 2 is the three dimensional view of the present invention;
FIG. 3 is the three dimensional view of the T-bushing, chuck head and chuck according
to the present invention;
FIG. 4 is the sectional view of the T-bushing according to the present invention;
FIG. 5 is the three dimensional view of a hobbing cutter;
FIG. 6 is a three dimensional view of the emery wheel with an outer annular ring according
to the present invention;
Fig. 7 is a schematic view of a hobbing cutter whose blades are to be shaved;
Fig. 8 is a schematic view of another example other than that shown in Fig. 7;
Fig. 9 is a schematic view showing the clearance angle of a hobbing cutter which is
under shaving.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0015] Referring to Fig. 2 and Fig. 3, the adjustable drill bit chuck of the present invention
which accommodate a grinder 100, is provided with a first drill chuck 100A and a second
drill chuck 100B. The former has a containment hole 101, and the latter has a T-bushing
200 with a containment hole 102 respectively. One end 201 of the T-bushing 200 can
be inserted into the containment hole 101, while the other end has a larger outer
diameter such that an outer flange 202 is emerged out of the containment hole 101
after insertion. Two, three, or four pairs of stop traps 203 are provided along the
circumference of the outer flange 202 according to the number of blades of the drill
or hobbing cutter to be shaved. The stop traps 203 can be engaged with corresponding
clamp studs 103 which are provided on the outer surface of the drill chuck so as to
hold the T-bushing 200 in place in the containment hole 101 of the drill chuck.
[0016] Referring to Fig. 4, the T-bushing 200 has a tapered hole 204 in it with a taper
angle such that the blade of the drill or hobbing cutter can keep a prescribed inclination
angle with the emery wheel when the drill or cutter head is inserted into the tapered
hole 204.
[0017] Returning to Fig. 3, in the present invention, the adjustable drill chuck is provided
with two pairs of stop pins 301, 302 along the outer flange 202 of the T-bushing 200
so as to control the turning angle of the drill bit chuck. As shown in Fig. 3, after
inserting the adjustable check head having confinement grooves 401, 402 into the tapered
hole 204, the confinement grooves 401, 402 and the stop pins 301, 302 cooperate to
control the turning angle of the chuck head 400 by their mutual positional relation
thereby defining the length of the cutter blade to be shaved.
[0018] Referring to Fig. 5, in the present invention, the T-bushing 200 of the adjustable
chuck is not only for holding a hobbing cutter 500 to be shaved by exposing a blade
length 501, but also can serve in the second drill chuck 100B to finish the clearance
angles 502 or recesses 503 of the cutter blades.
[0019] Referring to Fig. 6, if a tilted T type emery wheel 600 is used in the present invention,
it is provided an outer ring 601 with larger diameter than that of the main wheel
600 at one side thereof, the grinding surface of the outer ring 601 is covered with
a preferably thick emery compounds.
[0020] Referring to FIG. 7, when the blades of a hobbing cutter 500 is to be shaved, at
first the T-bushing 200 is inserted into the Z direction containment hole 101 of the
first drill bit chuck 100A, then the chuck head 400 holding the hobbing cutter 500
at the chuck side is inserted into the tapered hole 204 in the T-bushing 200 so as
to bring the hobbing cutter 500 in contact with the main body of the emery wheel 600
with a tilted angle θ. As the emery wheel 600 rotates, by turning the chuck head 400
according to the mutual positional relation between the confinement grooves 401, 402
and the stop pins 301, 302, the hobbing cutter 500 can be settled to shave its blade.
Taking the cutter with two-faced blade for example, as soon as one side of the blade
is finished, turning the T-bushing 200 180° and inserting it into the Z direction
containment hole 101 of the first drill bit chuck 100A so as to continue shaving the
other side of the blade.
[0021] Since the hobbing cutter 500 is in contact with the main body of the emery wheel
600 with a tilted angle θ, the tilted blade can be easily shaved. As shown in Fig.
8, by means of inclining center 500A of the cutter 500 against the corner 602 of the
emery wheel 600, the blades 504, 505 with different length can be effectively shaved
by turning the chuck head from 0° to 180°.
[0022] Referring to Fig. 9, when a clearance angle θ1 of the hobbing cutter 500 is to be
shaved, at first the T-bushing 200 is inserted into the Y direction containment hole
101 of the second bit chuck 100B, and then by inserting the chuck head 400 which holds
the hobbing cutter 500 into the tapered hole 204 of the T-bushing 200 such that the
hobbing cutter 500 is in contact with the outer ring 601 of the emery wheel 600 with
a tilted angle θ thereby making the cutter 500 to incline a certain angle against
the edge 602 of the outer ring 601. By so, the clearance angle of the blade of the
cutter 500 can be easily shaved.
[0023] Accordingly, by utilizing the T-bushing 200 with the tapered hole 204 together with
the emery wheel 600 with the outer ring 601, the present invention can be applied
to shave and finish the hobbing cutter 500 with two, three or even four blades conveniently
and easily only by turning the T-bushing 200.
[0024] Although the present invention has been disclosed and illustrated with respect to
preferred embodiments thereof, it is to be understood that the invention is not to
be so limited and that other changes and modifications can be made within the full
intended scope of the invention as hereinafter claimed.
1. Emery wheel grinding machine with adjustable drill bit chuck comprising:
an emery wheel for grinding and shaving a drill bit; a drill bit chuck for fastening
a drill bit; and a bushing in said chuck for insertion of the head of said drill bit;
wherein said bushing is a T-shaped bushing, one end thereof can be inserted into a
containment hole, while the other end is emerged out of said containment hole with
an outer flange, said outer flange in provided with several pairs of stop traps along
its circumference and can be engaged with corresponding clamp studs provided on the
outer surface of said drill bit chuck, and said T-bushing has a tapered hole in it.
2. The grinding machine as in claim 1, wherein the surface of said outer flange of said
T-bushing is provided with two pairs of stop pins for controlling the turning angle
of said drill bit chuck.
3. The grinding machine as in claim 1, wherein the number of said stop traps provided
along the circumference of said outer flange of said T-bushing is determined according
to number of cutter blades to be shaved.
4. The grinding machine as in claim 1, wherein the grinding wheel used in said grinding
machine is an emery wheel provided with an outer ring with larger diameter than that
of the main wheel.