Note: Descriptions are shown in the official language in which they were submitted.
21~S208
ROTARY ~u,~lNG BLADE A8REM~LY FOR A HAND-HE~D CUTTER
FIELD OF THE INVENTION
The present invention relates generally to
hand-held cutting tools and, more particularly, to a
cutting blade having a pinking or wave cutting edge.
RELATED APPLICATIONS
The present invention is a continuation-in-part
of Design Applications Serial No. 07/821,593, entitled
"Circular Pinking Blade Or Similar Article," filed on
January 15, 1992, and Serial No. 07/926,212, entitled
"Circular Wave Blade Or Similar Article," filed on August
5, 1992.
BACKGROUND OF THE INVENTION
A hand-held rotary cutter of the type
contemplated herein is shown and described in U.S. Patent
No. 5,101,564, entitled "Hand-Held Cutter Having A
Rotatable Circular Blade And Safety Guard," issued on
April 7, 1992. The rotary cutter of the type described
in this patent generally includes a hand-held handle
having a generally circular head mounted on one end which
includes an internal cavity and a planar surface on each
side. An activating member is pivotably mounted in the
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cavity for supporting a cutter blade on one of the planar
surfaces of the circular head with the blade b~ing
retractable to a guarded position in close proximity to
the planar surface of the head, and being movable in an
arcuate path to expose the edge of the blade for cutting.
SUMMARY OF THE PRESENT INVENTION
In accordance with the present invention a
cutter blade is provided which includes a cutting edge
having a pinking or wave form which is offset from the
planar surface of the blade, the blade being mountable
upon the rotary head for movement between storage and
cutting positions.
In accordance with another aspect of the
; invention a finger guard is provided which prevents the
forward movement of the fingers during a cutting stroke.
A further advantage of the invention relates to
the ability to interchange the cutter blades to -~
accommodate different cutting patterns.
Other principal features and advantages of the
invention will become apparent to those skilled in the
art upon review of the following drawings, the detailed
description and the appended claims.
BRIEF DESCRIPTION OF THE DRAWING
A preferred exemplary embodiment of the present
invention will be described in conjunction with the
appended drawing, wherein like numerals denote like
elements, and:
Figure 1 is a perspective view of a hand-held
rotary cutter in accordance with the present invention;
Figure 2 is an exploded view of the cutter
assembly o~ the rotary cutter of Figure 1.
Figure 2A is an alternate form of the cutter
blade.
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Figure 3 is an exploded view of the rotary
cutter.
Figure 4 is a side view of the rotary cutter
with a portion broken away to show the pivoting assembly
for the blade.
Figure 5 is an enlarged view of the pivoting
assembly.
Figure 6 is a cross sectional view taken on
line 6-6 of Figure 1.
Figure 7 is a cross sectional view taken on
line 7-7 of Figure 1.
Figure 8 is a cross sectional view taken on
line 8-8 of Figure 2A.
Figure 9 is a cross sectional view taken on
line 9-9 of Figure 2.
Before explaining at least one embodiment of
the invention in detail it is to be understood that the
invention is not limited in its application to the
details of construction and the arrangement of the
components set forth in the following description or
illustrated in the drawings. The invention is capable of
other embodiments or being practiced or carried out in
various ways. Also, it is to be understood that the
phraseology and terminology employed herein is for the
purposes of description and should not be regarded as
limiting.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to Figures 1 and 2, the rotary cutter
10 of the type contemplated herein includes a body 12, a
blade retainer 16, a retainer bolt 18, a spring washer
20, a retainer nut 22, and a lock lever 24. As best seen
in Figure 3, body 12 is formed of respective symmetrical
side parts 12A and 12B which, in assembly, form an
interior cavity therebetween. A pivoting member 28, a
locking pawl 30, and respective elastic bands 32 and 34
:. , . ." , . . .
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are disposed within the body cavity. In accordance with
the present invention cutting blades 14A or 14B are
mounted on retainer bolt 18 and held in abutting relation
to one or the other side of body 12.
sody 12 includes a handgrip portion 36 and a
cylindrical head 38 interconnected by an integrally
formed blending neck 40. As will be further described,
handgrip 36 manifests a three dimensional configuration
which not only comfortably fits either hand, but also, in
cooperation with neck 40, permits the user to guide
cutter 10 using either the thumb or forefinger, and
optimizes downward and longitudinal (forward or rearward)
force on blade 14A or 14B when in use.
Referring to Figures 1-3 and 7 the head 38
includes a planar disk or platform having substantially
flat side surfaces ~8A and 38B, manifesting a generally
circular periphery. The side surfaces 38A and 38B are of
a diameter greater than the diameter of blades 14A and
14B, and each side includes a transverse through bore 42
and an arcuate-shaped aperture 44 extending transversely
therethrough (Figures 2, 3). The major arcs 44A and 44B
of aperture 44 are concentric with bore 42.
Referring again to Figures 1 and 2, neck 40
provides a smooth, integral connection between handle
portion 36 and head 38, and is contoured to receive a
user's thumb or forefinger on the rear top surface
thereof. Neck 40 includes a forward top transverse
surface 41 comprising an arc concentric with bore 42, in
which a longitudinally disposed slot 46 is formed. As
best seen in Figures 3 and 6, respective apertures 48 are
also formed in the sides of neck 40, rearwardly of bore
42 and slot 46. A pin 50 is formed on the interior of
one or both of body side parts 12A and 12B. The relative
disposition and dimensional relationships of the various
components of body 12 will be described in more detail in
conjunction with Figures 2 and 3.
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The hand grip portion 36 is provided with a
finger guard 35 formed as an integral part of the hand
grip portion 36. In this regard, it should be noted that
one end 37 of the guard 35 is formed as an integral part
of the head 3B and the other end 39 extends rearward and
is formed as an integral part of the end of the hand grip
portion 36. With this arrangement the fingers of the
operator are protected from the cutting edge of the
blades 14A and 14B.
Referring to Figure 3, pivoting member 28 is
pivotally mounted within the head 38 and includes: a
generally planar body 52; a pivot pin 54 extending
perpendicularly from each side of body 52; respective
cylindrical bosses 56 symmetrically disposed on each side
of body 52 and having an axial bore 57 extending
therethrough; a stem 58 terminating in a thumb~lever 60;
a major cammed surface 62 terminating at a ledge 64; and
a hook 66. In assembly, the ends of pin 54 are received
in bores 42; bosses 56 are received in said arcuate-
shaped apertures 44; and stem 58 extends through slot 46,
with lever 60 disposed exteriorly of platform 38.
The blades 14A and 14B are rotatably secured to
boss 56 of pivoting member 28. In assembly, the end
surfaces of the bosses 56 are, as best seen in Figure 2,
substantially coplanar with the flat surfaces 38A and 38B
of head 38. One of the blades 14A or 14B is disposed
adjacent head 38, and blade retainer 16 adjacent to one
of the blades 14A or 14B, with central aperture 16A in
registry with boss bore 57. Retainer bolt 18 is
journalled through blade retainer 16, blade 14A or 14B,
bosses 56, and spring washer 20 and is threadedly engaged
by nut 22. The head 19 of retainer bolt 18 is suitably
received within a counterbore 17 formed in retainer 16.
A portion of the shaft of bolt 18 may be keyed, and bore
57 shaped accordingly, to prevent rotation of bolt 18
relative to pivoting member 28. With this arrangement
.
~ .. : - .. . . . -
2 0 8
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the blade 14 and blade retainer 16 can be quickly and
easily removed from the handle for cleaning and
reassembling to maintain sanitary conditions.
Blade 14A or 14B is rotatable about the shaft
of bolt 18. When nut 22 is fully engaged, spring washer
20 is compressed, causing retainer 16 to bear against
blades 14A or 14B with a predetermined force so that a
predetermined frictional resistance against rotation is
effected. The blade 14A is provided with a cutting edge
13 having a zigzag or pinking pattern as shown in Figures
1, 2, 3 and 9. The blade 14B is provided with a cutting
edge 15 having a wave pattern as shown in Figures 2A and
8.
In this regard the blade 14A is formed from a
relatively thin flat metal disc having a thickness of
approximately .016 inches. The cutting edge 13 on the
outer perimeter of the blade 14A has an angle of
convergence which is the same around the complete
periphery of the blade. It should be noted that the
cutting edge 13 around the periphery of the blade is
formed by indenting the edge 13 of the blade a~
predetermined intervals around the periphery of the blade
with the cutting edge 13 offset from the planar surface
of the disc 11. The cutting edge 13 is offset to one
side of the disc 11 to allow the disc 11 to be in sliding
contact with the planar surface 38A or 38B of the head
38.
The blade 14B shown in Figures 2A and 8 is also
formed from a thin flat metal disc 11 having a thickness
of approximately .016 inches. The cutting edge 15 on the
outer perimeter of blade 14B also has an angle of
convergence which is the same around the complete blade
circumference. The cutting edge 15 around the periphery
of the disc 11 is formed by indenting the cutting edge 15
from one side of the blade so that the cutting edge is
offset from the plane of disc 11.
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Pivoting member 28 is employed to controllably
move blade 14A or 14B relative to head 38 between cutting
and retracted positions. Referring now to Figures 4 and
5, stem 58 may be made to travel the extent of slot 46,
causing member 28 to pivot about pin 54, such that bosses
56 (and thus the axis of blades 14A and 14B to~ travel
through the arc defined by aperture 44. As shown in
Figure 4, when member 28 is in the rearmost (retracted)
position, the edge of blades 14A and 14B is contained
within the area of head 38. The blade is thus retracted.
As shown in Figure 5, when actuator lever 60 is pushed
forward, to place stem 58 in the vicinity of the forward
extremity of slot 46, member 28 rotates counter-clockwise
into a forward (cutting) position, in which a portion of
the periphery of blade 14A or 14B extends beyond the
periphery of cylindrical head 38. Blade 14A or 14B is
thus disposed in an exposed (cutting) position.
Locking pawl 30, also pivotally mounted within
handle 36, cooperates with lever 24 to selectively lock
the blade 14A or 14B in the cutting position. Referring
now to Figures 3 and 6, locking pawl 30 includes a
terminal portion 68, respective cylindrical posts 70
keyed for rotation with internal key bores in levers 24
and 26, and an end hook portion 72. Posts 70 are
journalled through apertures 48 in body sides 12A and
12B, and are affixed to levers 24 and 26 such that
terminal portion 68 is selectively pivoted about the axis
defined by posts 70 in response to rotation of either
lever 24 or lever 26. Elastic band 32 is fixed over hook
portion 72 of actuator pawl 30, and extends over post 50
to provide a counter-clockwise rotational bias on locking
pawl 30. Member 28, on the other hand, is biased for
clockwise rotation by elastic band 34; elastic band 34 is
fixed to hook 66 at one end, and at the other to post 50.
As shown in Figures 4 and 5, the relative
dimensions and dispositions of member 28 and pawl 30 are
-... : , .. . . . . . .
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- 8 -
such that pawl terminal portion 68 normally rides on cam
surface 62 of member 28. When member 28 is rotated
counter-clockwise (by forward movement of stem 58 within
slot 46), cam surface 62 moves relative to pawl 30, and
5 pawl terminal portion 68, under counter-clockwise
rotational bias, ultimately drops off cam surface 62 at a
step or ledge 64 (at a point corresponding to stem 58
being located at the forward extremity of slot 46 and
bosses 56 at the lower extremity of arcuate-shaped
aperture 44) (Figure 5). The end of pawl 30 lodges
against ledge 64 of member 28, locXing member 28 in the
forward position.
To release pivoting member 28 from the forward
position, lever 24 or 26 is rotated in a clockwise
direction in Figure 1, causing pawl 30 to likewise
rotate, and lift out of ledge 64. The bias from elastic
band 34 causes clockwise rotation of member 28, again
disposing cam surface 62 under pawl 30. Member 28 thus,
under bias, resumes the retracted position.
As previously mentioned, handgrip 36 manifests
a contoured configuration which fits either the right or
left hand comfortably, and permits the user to guide
cutter 10 using either a thumb or forefinger, while at
the same time exerting the necessary downward and forward
force on blade 14A or 14B. The finger guard 35 provides
protection from the blade 14A or 14B by preventing .
forward motion of the fingers of the operator.
Thus, it should be apparent that there has been
provided in accordance with the present invention a
rotary c~tting blade assembly for a hand-held cutter that
fully satisfies the aims and advantages set forth above.
Although the invention has been described in conjunction
with specific embodiments thereof, it is evident.that
many alternatives, modifications and variations will be
apparent to those skilled in the art. Accordingly, it is
intended to embrace all such alternatives, modifications
21 D~ 2 08
and variations that fall within the spirit and broad
scope of the appended claims.
