U.S. patent application number 11/648788 was filed with the patent office on 2007-05-17 for hole saw slug removal device.
Invention is credited to Abelardo Jasso.
Application Number | 20070110527 11/648788 |
Document ID | / |
Family ID | 35054428 |
Filed Date | 2007-05-17 |
United States Patent
Application |
20070110527 |
Kind Code |
A1 |
Jasso; Abelardo |
May 17, 2007 |
Hole saw slug removal device
Abstract
The hole saw slug removal device is constructed to fit within a
hole saw and provides for automatic ejection of waste slugs from
within the hole saw. The hole saw slug removal device has two discs
affixed on either end of a compression spring. The device is
inserted into the hole saw, and one disc retains the compression
spring within the hole saw by locking onto the drill bit or against
the inner surface of the hole saw. Upon operation of the hole saw,
the spring compresses and the other disc is pushed down by the
force of the sawing, the spring expanding to automatically eject
the slug from within the hole saw when the saw is withdrawn from
the workpiece. The hole saw pilot bit may have an annular groove on
the shank between the flat(s) and fluted cutting edges that is
engaged by one of the discs.
Inventors: |
Jasso; Abelardo; (Fontana,
CA) |
Correspondence
Address: |
LITMAN LAW OFFICES, LTD.
P.O. BOX 15035
CRYSTAL CITY STATION
ARLINGTON
VA
22215
US
|
Family ID: |
35054428 |
Appl. No.: |
11/648788 |
Filed: |
January 3, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10817944 |
Apr 6, 2004 |
7160064 |
|
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11648788 |
Jan 3, 2007 |
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Current U.S.
Class: |
408/68 |
Current CPC
Class: |
Y10T 408/895 20150115;
Y10T 408/51 20150115; Y10S 408/703 20130101; B23B 51/0453
20130101 |
Class at
Publication: |
408/068 |
International
Class: |
B23B 51/04 20060101
B23B051/04 |
Claims
1. A hole saw slug removal device for automatic slug ejection,
comprising: a hole saw pilot drill bit having an upper shank
portion defining at least one flat, a lower portion having fluted
cutting edges, and an annular groove disposed between the upper and
lower portions; a helical compression spring having opposed first
and second ends; a first annular disc attached to the compression
spring at the first end of the spring, the first disc being
slidable over the fluted cutting edges; and a second disc attached
to the second end of the compression spring, the second disc being
annular and defining an inner circumference, the second disc
releasably engaging the groove defined in the pilot drill bit, the
compression spring being concentrically disposed around the bit and
the first disc slidably disposed about the fluted cutting
edges.
2. The hole saw slug removal device as recited in claim 1, further
comprising a plurality of resilient internal teeth formed on the
inner circumference edge of said second disc, the teeth releasably
engaging the annular groove.
3. The hole saw slug removal device as recited in claim 2, wherein
said second disc is convexly shaped.
4. The hole saw slug removal device as recited in claim 1, wherein
said first and second discs are planar.
5. The hole saw slug removal device as recited in claim 1, wherein
said first and second discs are welded to said compression
spring.
6. The hole saw slug removal device as recited in claim 1, wherein
said compression spring is frustoconical, tapering from a wide
diameter adjacent said second disc to a narrow diameter adjacent
said first disc.
7. The hole saw slug removal device according to claim 1, further
comprising: a hollow, elongated, cylindrical body having a base at
one end and a plurality of cutting teeth at an opposing end, the
cylindrical body defining a hole saw; and an arbor attached to the
base, the arbor being releasably attached to the upper shank
portion of said pilot drill bit, said first and second discs and
said spring being disposed within the hole saw, whereby said spring
is compressed when said hole saw cuts into a work surface and
expands when the hole saw is withdrawn from the work surface in
order to eject a slug cut from the work surface out of the hole
saw.
8. A hole saw slug removal device for automatic slug ejection,
comprising: a hole saw pilot drill bit having an upper shank
portion defining at least one flat, a lower portion having fluted
cutting edges, and an annular groove disposed between the upper and
lower portions; and an ejector assembly having: a helical
compression spring having opposed first and second ends; a first
annular disc attached to the compression spring at the first end of
the spring, the first disc being slidable over the fluted cutting
edges; and a second disc attached to the second end of the
compression spring, the second disc being annular and defining an
inner circumference, the second disc having means for releasably
engaging the groove defined in the pilot drill bit in order to
attach the ejector assembly to the pilot drill bit, the compression
spring being concentrically disposed around the bit and the first
disc slidably disposed about the fluted cutting edges.
9. The hole saw slug removal device according to claim 8, wherein
said means for releasably engaging the groove comprises a plurality
of resilient teeth formed on the inner circumference of said second
disc.
10. The hole saw slug removal device according to claim 8, wherein
said compression spring is frustoconical, tapering from a wide
diameter adjacent said second disc to a narrow diameter adjacent
said first disc.
11. The hole saw slug removal device according to claim 8, wherein
the upper shank portion of said pilot drill bit has an elongated
hexagonal shape, defining a plurality of flats defining bearing
surfaces for an arbor set screw.
12. A hole saw slug removal device for automatic slug ejection,
comprising: a hole saw pilot drill bit having an upper shank
portion defining at least one flat, a lower portion having fluted
cutting edges, and an annular groove disposed between the upper and
lower portions; and an ejector assembly having: a helical
compression spring having opposed first and second ends; a slug
bearing surface attached to the first end of the compression
spring; and means for releasably attaching the second end of the
compression spring to the pilot drill bit, the second disc being
annular and defining an inner circumference, the means for
releasably attaching engaging the groove defined in the pilot drill
bit, the compression spring being concentrically disposed around
the bit and the first disc slidably disposed about the fluted
cutting edges.
13. The hole saw slug removal device according to claim 12, wherein
said slug bearing surface comprises a flat, annular disc.
14. The hole saw slug removal device according to claim 12, wherein
said compression spring is frustoconical, tapering from a wide
diameter adjacent said second disc to a narrow diameter adjacent
said first disc.
15. The hole saw slug removal device according to claim 12, wherein
said means for releasably attaching comprises a second disc
attached to the second end of the compression spring, the second
disc being annular and defining an inner circumference, the inner
circumference resiliently engaging the groove.
16. The hole saw slug removal device according to claim 12, wherein
said means for releasably attaching comprises a second disc
attached to the second end of the compression spring, the second
disc being annular and defining an inner circumference, the inner
circumference having a plurality of teeth resiliently engaging the
groove.
17. The hole saw slug removal device according to claim 12, wherein
said second disc is convex and formed from resilient material.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is being filed as a continuation-in-part of
U.S. patent application Ser. No. 10/81 7,944, filed Apr. 6,
2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to slug removal devices and,
more specifically, to a hole saw slug removal device used to
automatically eject plugs that have been sawed from material.
[0004] 2. Description of the Related Art
[0005] A hole saw is a type of saw used in drilling circular holes
in various materials, such as wood, metal, drywall, etc. The hole
saw typically has a cylindrical body, one edge of which is
serrated. In addition, the cylindrical body contains openings at
both ends that allow for a drill bit to be extended therefrom. The
drill bit juts out just beyond the serrated edge and stabilizes the
hole saw against the surface of the material. When used with a
drill power source, the serrated edge of the hole saw body rotates,
creating circular holes in the material.
[0006] A substantial problem that is faced in employing the hole
saw to drill holes in a surface is that the waste left over,
typically called a slug, is difficult to extract from within the
body of the hole saw. The user is required to stop after each hole
is sawed and manually extract the slug from the hole saw. This
manual slug removal technique is time-consuming and takes
substantial effort for the user. Thus, a hole saw that allows for
quick removal of the slug provides much greater use for the user.
Automatic removal of the slug would be preferential to
non-automatic slug removal.
[0007] The related art endeavors to solve the problem of slug
removal by either developing different types of hole saws to eject
the slugs or by developing a slug removal device to be connected to
the hole saw.
[0008] U.S. Pat No. 3,390,596, issued Jul. 2, 1968 to Trevathan,
discloses a cutting head assembly that may be utilized to bore
circular holes. The cutting head assembly has a cylindrical body
with a plurality of cutting teeth on one edge of the body. The
plurality of cutting teeth appear to preferably consist of inwardly
and outwardly extending teeth. A spring is positioned within the
body portion, and a spring-actuated disc is inserted within the
cylindrical body, the disc being used to decrease distortion in the
hole shape. The disc and spring appear to be held within the
cylindrical body of the cutting head assembly by the inwardly
extending teeth. When attached to a power source, the cutting head
assembly is rotatably driven about its axis such that a hole is cut
into the surface of the material on which it is placed.
[0009] U.S. Pat No. 4,652,185, issued Mar. 24, 1987 to Malrick,
shows a hole saw and slug-removing device. The hole saw has a
cylindrical body through which a drill bit may pass, one edge o the
cylindrical body being serrated such that when the hole saw is
used, a circular hole is drilled into a surface. A plug member is
positioned within the hole saw using a set of screws inserted
through an annular collar and into the plug member. The screws
maintain the plug member within the hole saw. It appears that a
spring may be positioned within the hole saw between an inner
portion of the hole saw and the plug member and become compressed
when the hole saw is operated. After the hole has been made, the
hole saw operator may extract the slug from within the hole saw by
manually pressing down on the annular collar.
[0010] U.S. Pat. No. 5,816,752, issued Oct. 6, 1998 to Benjamin,
describes a slug removal system. The system includes a knockout
device that ejects slugs after a hole is drilled using a hole saw.
The knockout device has a cylindrical body, which is tapered at one
end, and fits inside the hole saw. A spring is included as part of
the slug removal system. As the hole saw is used, the knockout
device is pushed back against the spring. When the hole is
completed, the spring decompresses, ejecting the slug from within
the hole saw. A set of screws secures the knockout device to the
hole saw at predetermined depths.
[0011] Although the related art does address devices for slug
removal, what is needed is a simple device, easily constructed,
that automatically removes slugs. What is further needed is a
device for slug removal that may be attached to hole saws that lack
a slug removal device. The device should allow for simple insertion
within the body of a hole saw and should not require the addition
of attachment means that are situated on the outside of the hole
saw body. Further, it is advantageous to have a slug removal device
that may be removed and later reattached to a hole saw.
[0012] None of the above inventions and patents, taken either
singly or in combination, is seen to describe the instant invention
as claimed. Thus a hole saw slug removal device solving the
aforementioned problems is desired.
SUMMARY OF THE INVENTION
[0013] The hole saw slug removal device is a center device
constructed to fit within a hole saw. The slug removal device
provides for automatic ejection of waste slugs from within the body
of the hole saw. The hole saw slug removal device generally
includes a compression spring fixed between two discs, the discs
being affixed to the spring. The device is then inserted within the
hole saw. Upon operation of the hole saw, the spring compresses,
and one disc is pushed down by the force of the sawing. After
sawing is completed, the spring decompresses, and the disc is
pushed up. The disc then automatically ejects the waste slug that
has become trapped within the hole saw.
[0014] In one embodiment, the disc to be inserted into the hole saw
has a center opening with internal teeth and is convexly shaped.
The hole saw slug removal device is pressed into the hole saw, and
when the user determines, the device will lock into the hole saw by
latching against the drill bit. In another embodiment, the disc to
be inserted into the hole saw has external teeth and is concavely
shaped. Following depression into the hole saw, when the user
determines, the device locks into the hole saw by latching against
the hole saw body. In another embodiment, the lower disc is omitted
and the hole saw slug removal device with the spring and one top
disc is permanently affixed to the bottom of the hole saw.
[0015] One aspect of the invention is that the hole saw slug
removal device provides for automatic removal of waste slugs in
contrast to more time-consuming manual removal of the slugs.
Another aspect of the invention is that the hole saw slug removal
device may be provided as a separate piece from the hole saw. It
may be purchased at a separate time from the hole saw, then
inserted and "locked" within the hole saw for convenient slug
removal. In one embodiment, the device may be removed from the hole
saw, so that the slug removal device may be reused. A further
aspect of the invention is that the slug removal device has a
simple design, allowing for minimal expense in the construction of
the device. The simple design lacks additional costly or obtrusive
elements such as screws or the like to attach the slug removal
device to the hole saw.
[0016] In another embodiment, the hole saw slug removal device
extends to the combination of a pilot bit and a resilient slug
ejection assembly as described above, the pilot bit having an
annular groove defined in the shank that is resiliently engaged by
the internal teeth of the bottom or proximal disc. The compression
spring may be a helical spring having coils of progressively
smaller diameter extending from the bottom disc to the top or
distal disc, giving the helical spring a frustoconical shape. This
gives the outer diameter of the coils adjacent the top disc, which
bears against the slug, more room to expand within the hole saw as
the spring is compressed in order to prevent the spring from
binding in the hole saw.
[0017] The invention provides improved elements and arrangements
thereof for the purposes described and is inexpensive, dependable
and fully effective in accomplishing its intended purposes.
[0018] These and other features of the present invention will
become readily apparent upon further review of the following
specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is an elevational side view of a hole saw and hole
saw slug removal device, partly in section, according to a first
embodiment of the present invention.
[0020] FIG. 2 is a perspective view of the hole saw and hole saw
slug removal device as shown in FIG. 1.
[0021] FIG. 3 is an exploded, perspective view of the hole saw slug
removal device of the first embodiment.
[0022] FIG. 4 is an elevational side view of a hole saw and hole
saw slug removal device, partly in section, according to a second
embodiment of the present invention.
[0023] FIG. 5 is an exploded, perspective view of a hole saw slug
removal device of the second embodiment.
[0024] FIG. 6 is an elevational side view of a hole saw and hole
saw slug removal device, partly in section, according to a third
embodiment of the present invention.
[0025] FIG. 7 is an exploded, perspective view of a fourth
embodiment of a hole saw slug removal device according to the
present invention.
Similar reference characters denote corresponding features
consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] The present invention is a hole saw slug removal device,
designated generally as 10 in the drawings. The hole saw slug
removal device 10 is designed to fit inside a hole saw 12, as shown
in FIGS. 1, 2 and 4. The hole saw 12 includes a cylindrical body 14
having two openings to allow for a drill bit 30 to be inserted
therein. A serrated edge 16 of the cylindrical body 14 is used for
cutting into a material surface 60.
[0027] Referring first to FIG. 3, the hole saw slug removal device
10 is shown with a drill bit 30. The slug removal device 10 allows
for the drill bit 30 to fit within the device 10. The drill bit 30
guides the hole saw 12 against a surface 60 of the material to be
cut. The slug removal device 10 is made up of a compression spring
20 fixed between two discs 22 and 24. The top disc 22 is a disc of
any type, for example, a washer, and may be flat or shaped in a
different manner. The top disc 22 may be permanently attached to an
end of the spring 20. A bottom disc 24, which may be a washer, may
be permanently affixed to the other end of the spring 20. The top
22 and bottom 24 discs may be annular. Both discs 22 and 24 have a
hole in the center to allow for the drill bit 30 to fit through
each disc 22 and 24.
[0028] As shown in FIGS. 1 and 4, the bottom disc 24 serves as a
locking mechanism with which to retain the compression spring 20
within the hole saw 12. The bottom disc 24 contains a means for
retaining the compression spring 20 within the hole saw 12. In one
embodiment, shown in FIG. 1, a means for retaining the compression
spring 20 within the hole saw 12 is a set of inner teeth 26 of the
bottom disc 24 that lock the slug removal device 10 onto an outer
portion of the drill bit 30. As shown in FIGS. 1 and 3, the bottom
disc 24 is convexly shaped. In another embodiment, shown in FIG. 4,
a means for retaining the compression spring 20 within the hole saw
12 is a set of outer teeth 28 of the bottom disc 24 that lock the
slug removal device 10 onto an inner surface of the cylindrical
body 14 of the hole saw 12. As shown in FIGS. 4 and 5, the bottom
disc 24 is concavely shaped.
[0029] Following use of the hole saw 12, the hole saw slug removal
device 10 may be removed from the hole saw 12, depending on the
type of disc used. For example, if a convex inner-toothed bottom
disc 24 is utilized, as in FIG. 1, after the drill bit 30 is
disconnected from the hole saw 12, the slug removal device 10 may
easily slip out of the hole saw 12. In contrast, if a concave
outer-toothed bottom disc 24 is utilized, as in FIG. 4, even after
the drill bit 30 is removed from within the hole saw 12, the slug
removal device 10 will stay lodged within the hole saw 12.
[0030] As shown in FIGS. 1, 2, and 4, after the hole saw slug
removal device 10 is inserted within the hole saw 12, an arbor 40
is used to attach the hole saw 12 to a portable drill for powering
the hole saw 12. When operated, the hole saw 12 cuts into a
surface, such as drywall or the like. The top disc 22 is depressed,
compressing the spring 20. A volume of waste material, or slug,
then becomes wedged into the hole saw 12. Following operation of
the hole saw 12, the spring 20 decompresses and the top disc 22 is
forced out of the hole saw 12. The slug is then automatically
ejected from within the hole saw 12.
[0031] Alternatively, as illustrated in FIG. 7, the drill bit 30,
which is a pilot bit for a hole saw, may have an annular groove 100
formed along the outer surface thereof above the fluted cutting
edges of the bit 30 and below the flat(s) on the upper portion of
the shank that the arbor's set screw bears against. It will be
understood that hole saw pilot bits come in a variety of
configurations, and may be provided with a single flat or a
plurality of flats that may be engaged by the set screw, and the
flats may extend continuously along the entire length of the upper
shaft, or may be formed in one or more discrete notches. For
example, the upper portion of the shank may be octagonal,
hexagonal, or cylindrical through about 270.degree. of its
circumference, with a flat being formed across the remaining
90.degree., the flats being continuous along the length of the
upper portion of the shaft so that the arbor may be adjustably
positioned along the shaft in order to adjust the length of fluted
cutting edges extending below the teeth of the cylindrical hole saw
body 14. Alternatively, the upper portion of the shank may be
cylindrical, with a flat formed in one notch for use with a single
hole saw. The upper portion of the shank of the pilot bit 30 of the
present invention may have any of these configurations, the annular
groove 100 being disposed between the flat(s) on the upper shank
and the fluted cutting edges of the bit 30.
[0032] The inner circumference 110 of bottom disc 24 may be
positioned within groove 100 of the drill bit 30, the internal
teeth 26 resiliently engaging the groove 100, allowing for secure
positioning of the device 10 with respect to the drill bit 30, and
allowing the device 10 to rotate freely with the bit 30. In FIG. 7,
the spring 20 is shown as having a substantially frustoconical side
profile, with the diameter of the helix forming spring 20 adjacent
the bottom disc 20 being greater than diameter the diameter of the
helix adjacent the top disc. The annular top disc 22 is slidable
over the fluted cutting edges of pilot bit 30, so that the slug
bears against top disc 22 and compresses spring 20 as the teeth of
cutting cylinder 14 penetrate work surface 60. When the hole saw 14
is withdrawn from the work surface, 60, compression spring 20
expands, thereby ejecting the slug from cylindrical body 14. The
tapered, frustoconical shape of compression spring 20 allows room
for the coils adjacent top disc 22 to expand laterally as spring 20
is compressed within cylindrical body 14, preventing the spring 20
from binding against the wall of cylindrical body 14 and ensuring
ejection of the slug.
[0033] In another embodiment shown in FIG. 6, the hole saw slug
removal device 10 is permanently attached to the hole saw 12.
According to this embodiment, the slug removal device 10 consists
of the compression spring 20 and the top disc 22, which is attached
to one end of the compression spring 20. The other end of the
compression spring 20 is permanently affixed to the bottom end 18
of the hole saw 12. When the hole saw 12 is operated, the top disc
22 is depressed further into the hole saw 12 by the force of the
sawing, compressing the spring 20. A waste slug becomes lodged into
the hole saw 12. After the sawing is completed, the compression
spring 20 presses the top disc 22 forward and the waste slug is
automatically ejected from the hole saw 12.
[0034] Preferably, device 10 is formed from stainless steel, which
is then electro-polished. The elements forming device 10, i.e.,
discs 22 and 24 and spring 20, are preferably laser-welded
together. It will be understood that instead of resilient teeth 26,
bottom disc 24 may have any other means for resilient engaging
drill bit 30, e.g., a spring-biased detent mechanism.
[0035] It is to be understood that the present invention is not
limited to the embodiments described above, but encompasses any and
all embodiments within the scope of the following claims.
* * * * *