Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF THE INVENTION
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(1) Field of the Invention
This invention relates to a power actuated cutting
tool.
Hereinafter the cutting tool of the invention will be
described in relation to the cutting of fibreboard. However,
it will be appreciated that this is not the only application of
the cutting tool and that it can be~used for cutting other
materials, especially sheet material.
(2) Description of the prior art
Hitherto in regard to the cutting of fibreboard, the ~;
usual methods adopted were either manual or power actuated.
Manual methods have not been entirely satisfactory because
they are not suitable in the cutting of fibreboard of strength-
ened characteristics. Although such strengthened fibreboard
could be cut by a power tool equipped with an abrasive circular `
cutting blade, this creates a dust problem which could prove
adverse to the ope.rator's health.
BRIEF SUMMAR~ OF THE INVENTION
It is therefore an object of the invention to provide
a power actuated cutting tool which overcomes or minimizes the
above-mentioned difficulties of the prior art.
The invention, as herein claimed, essentially com- -
prises a power actuated cutting tool for the cutting of sheet
material comprising a cutter body having a cutting blade which
reciprocates in an up and down direction relative to the plane
of the material being cut, said cutting blade being a plate-
like member having a base surface with two opposed cutting
edges, drive means for driving said cutting blade, gear means
interconnecting said drive means and said cutting blade so as
to provide the reciprocatory cutting movement of the cutting
blade, both the gear means and the drive means being housed in
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the cutter body, said cutter body having a base platform located ~
below said cutting blade, said base platform having an elongate ~ -
slot formed therein, said elongate slot having two opposed
cutting edges each of which cooperably mates with a respective
cutting edge of the cutting blade when the sheet material is cut,
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with said base platform-acting as a support for the sheet
material when said cutting blade reciprocates up and down
relative to said slot so as to cut the sheet material there-
between, and further including a cutter blade support shaft which
is attached at one end thereof to said gear means and at its
other end to said cutter blade, and releasable attachment means
between the support shaft and the cutter blade.
The drive means may be of any appropriate type and is
suitably-an electric motor actuated from an A.C. source. Both
the electric motor and gear means are housed in the cutter body
which may be of any appropriate configuration. The support
shaft depends from an aperture located in the undersurface of
the cutter body. The support shaft carries the cutting blade
at its free end.
The c~tting edges of the blade are provided in the
lowermost edge. It is preferred that the cutting edges be
tapered so that they slope downwardly from the leading end
~i.e. that end of the cutting edges that are proximal to the
material being cut) to the trailing end. The reason for this
is that it facilitates the passage of the sheet material being
cut past the cutting blade as the cutting tool of the invention
moves along the sheet material or alternatively if the sheet -
material is pushed through the cutting tool.
As said, the cutting blade is releasably attached
to the support shaft and this may be achieved in any convenient
manner. In one form a locking pin may be inserted through `-
co-aligned apertures provided on opposite sides of the ~
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rectangular cutting blade and mounting aperture in the support
shaft. In an even more preferred form the mounting aperture
may be in the form of an elongate slot to facilitate adjustment
of the cutting blade relative to the material being cut.
- There is also, as said, a base support platform or
foot for the sheet material being cut as it is fed through
the cutting tool so as to maintain the sheet material in an even
horizontal plane and facilitates the cutting operation.
Suitably this base support may be integral with or otherwise
attached to the above-mentioned depending portion of the cutter
body below the guide plate. The base support is desirably
plate-like in configuration. ~;
In the base support there is provided an elongate
slot which suitably has a similar cross-section to the transverse
slot located in the guide plate but desirably of greater width. -
The elongate slot extends throughout the depth of the base ;
platform with the side surfaces thereof preferably tapering
slightly outwardly from the top side edges to the bottom side
edges.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF
'! THE DRAWINGS
Reference is now made to a preferred embodiment of the
invention as shown in the accompanying drawings wherein:
Fig. 1 is a sectional view of a cutting tool cons-
tructed in accordance with the invention;
! Fig. 2 is a front view of the tool shown in Fig. 1
~ith the components of the cutting tool shown separately from
the cutter body and base platform assembly, and
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Fig. 3 is an exploded perspective view of the cutting
blade and base platform assembly.
DETAlLED DESCRIPTION OF THE PREFERRED EMBODIMENTS
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In the drawings, the cutter body 10 includes the drive
motor 11 and gearing means including gear wheel 12, associated
gear wheel 13 which meshes with gear 14. Gear 14 is provided
with eccentric 15 and the connection member 18 (Fig. 2) having
a peripheral bearing 19 fitting about eccentric 15 as shown.
Member 18 is provided with lug 17 which is pivotally attached
to support shaft 20 by pivot pin 28 as shown. Thus as
eccentric 15 rotates in conjunction with gears 12, 13 and 14,
shaft 20 reciprocates up and down relative to the cutter body
10. This is clearly shown in Fig. 2. Member 18 is retained on
eccentric 15 by slip ring 16. Shaft 20 moves up and down in
guide sheeve 21 in cutter body 10.
Cutter blade 26 is shown releasably attached to shaft
20 by bolt 24 inserted through elongate slot 23 of a vertical
extension 22 of blade 26 and through aperture 29 of shaft 20.
Base platform assembly or foot assembly 30 is
releasably attached to cutter body 10 (see Fig. 3). Assembly ,
30 includes base plate 25 and shear plate 27 and elongate
slot 31.
The blade 26 is fastened to shaft 20 utilizing
C adjusting screw 3~ as shown in Fig. 2 and then bolt 24 is
inserted through slot 23 and aperture 29. -
For thicker sheet materials the blade 26 may be set
above the slot 31 so that in the lowermost point of its motion
it is just above slot 31. For thinner materials the blade 26
may be set so that it may protrude into slot 31 on its down-
ward stroke.
By the provision of the base support slot 31, dust and
debris from the sheet material being cut may fall therethrough
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as the cutting~tool of the invention moves along a predetermined
cutting line marked on the sheet material. -
It will be seen in Fig. 3 that the bottom of blade
26 has two opposed cutting edges 32 which cooperate with
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opposed cutting edges 33 of slot 31 for the cutting of the sheet
material. ~here also are provided two adjustment plates 34
which define the width of the slot 31. --
In operation of a preferred embodiment of the invention
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the sheet material to be cut such as fibreboard is fed through
the confines of the cutting tool between the base support 25 and
the bevelled cutting edge of the cutting blade 26. As it is `
cut, the sheet material is divided into two sections with each
section falling on either side of the depending portion of the
cutter body supporting the base support 25. Because of its
j ~ reciprocating up and down movement, the cutting blade has little
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; difflculty in cutting through even sheet material of strengthened
character. Also because of up and down movement of the cutting
, ~ blade very little debris such as dust is generated by the
f~ ` operation of the cutting tool when compared to the dust
l; 20 generated by an abrasive saw.
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