NZ785566A - Finger Grip for Shears - Google Patents
Finger Grip for ShearsInfo
- Publication number
- NZ785566A NZ785566A NZ785566A NZ78556622A NZ785566A NZ 785566 A NZ785566 A NZ 785566A NZ 785566 A NZ785566 A NZ 785566A NZ 78556622 A NZ78556622 A NZ 78556622A NZ 785566 A NZ785566 A NZ 785566A
- Authority
- NZ
- New Zealand
- Prior art keywords
- finger grip
- shears
- lever
- thumb
- finger
- Prior art date
Links
- 210000003811 Fingers Anatomy 0.000 claims abstract description 108
- 210000003813 Thumb Anatomy 0.000 claims abstract description 55
- 210000000988 Bone and Bones Anatomy 0.000 claims abstract description 4
- 238000003780 insertion Methods 0.000 claims abstract description 4
- 150000002500 ions Chemical class 0.000 claims description 4
- 230000000875 corresponding Effects 0.000 claims 2
- 238000005520 cutting process Methods 0.000 abstract description 30
- 230000035882 stress Effects 0.000 description 6
- 210000003205 Muscles Anatomy 0.000 description 5
- 239000000463 material Substances 0.000 description 4
- 239000002184 metal Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000006011 modification reaction Methods 0.000 description 2
- 230000036633 rest Effects 0.000 description 2
- 210000004247 Hand Anatomy 0.000 description 1
- 210000003491 Skin Anatomy 0.000 description 1
- 229940035295 Ting Drugs 0.000 description 1
- 210000000707 Wrist Anatomy 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000002708 enhancing Effects 0.000 description 1
- 210000001699 lower leg Anatomy 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002035 prolonged Effects 0.000 description 1
- 239000007779 soft material Substances 0.000 description 1
Abstract
shears upper finger grip has a lower substantially flat inner surface arranged in a transverse plane substantially normal to a cutting plane and dimensioned and configured to enable substantially full insertion of a thumb metacarpal bone from a right lateral side and for receiving the ball of the thumb to enable the thumb to be moved to a position on a left lateral side to an orientation substantially parallel to the cutting plane and to position the hand’s thenar eminence into abutment against the flat inner surface while positioning at least exterior right lateral portions of the upper finger grip in abutment against the palm beyond the hand’s thenar crease and into the region of at least one of the hand’s palmar creases to enable the thenar eminence and palm of the hand to oppose the forces applied by the fingers acting on the lower finger grip. thumb to enable the thumb to be moved to a position on a left lateral side to an orientation substantially parallel to the cutting plane and to position the hand’s thenar eminence into abutment against the flat inner surface while positioning at least exterior right lateral portions of the upper finger grip in abutment against the palm beyond the hand’s thenar crease and into the region of at least one of the hand’s palmar creases to enable the thenar eminence and palm of the hand to oppose the forces applied by the fingers acting on the lower finger grip.
Description
IN THE UNITED STATES PATENT AND TRADEMARK OFFICE
A Non-Provisional Patent Application for a:
FINGER GRIP FOR SHEARS
Invented by:
Michael H. Panosian
Joshua M. Keeler
CROSS-REFERENCE(S) TO RELATED APPLICATION(S)
The present application is a Divisional of, and claims the benefit of the filing date of
US ation No. ,935, filed on 25-February-2021, entitled " FINGER GRIP FOR
SHEARS," the contents of which are hereby expressly incorporated by reference in their
entirety, under 35 U.S.C. § 120.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to hand operated g tools and, more
specifically, to a finger gripping structure for cutting tools such as shears, snips and scissors.
2. Description of the Prior Art
Many hand-operated tools, such as scissors, shears and snips, have been proposed over
the years in us configurations to facilitate the cutting of various materials ranging from
light or soft materials to heavy materials such as sheet-metal. While the goals of most of these
cutting tools have been design to allow for the comfortable use of the tools, most designs
frequently cause user stress, strain and fatigue.
While it is generally understood that the strengths of all the fingers of the hand are more
or less the same or equal, gripping or squeezing the handles of scissors, shears or snips normally
involves one finger, the thumb, acting on one upper finger grip while the remaining four s
act on the other or opposing finger grip to counter the force applied by the thumb. The thumb,
therefore, must apply a disproportionate force by one finger to counter the collective opposing
forces applied by the remaining four fingers. This results in increased stresses on the flexor
muscles of the thumb. Consequently, this results in user fatigue, especially with extended use
and the cutting of heavier materials such as cardboard, metal and the like.
U.S. Patent 454,735 to ch ses a shears that includes a broad outwardly and
rearwardly extending seat or rest that extends to the e of the palm of the hand and upon
which a n of the hand rests when the shears are used. Extending from the seat or rest is
an extension upon which the thumb and the ball of the thumb rest, the whole palm of the hand
being utilized to sustain the weight of the body when operating the shears. However, the
extended seat or rest continues to rely on the thumb for ation of forces during g.
Also, the shape of the extension and the seed arrest is convex forming one or more peaks that
potentially apply one or more pressure points resulting in excessive points of stress and, with
extended use, pain and fatigue to the user. A similar structure is disclosed in related U.S. Patent
760, 204.
U.S. Patent 968, 219 to Wheeler discloses a shears designed to be used for longer time
and with less fatigue to the operator. The shears includes an oblique thumb loop that lies in a
plane at an angle of 45° to the plane of the finger bow so that ing the thumb into the bow
in alignment with the wrist and after passing through the bow bears against the shank by
ting the thumb bow. The power applied to operate the thumb bow is applied nearly
transversely to the thumb and above the second joint of the thumb. While the orientation of the
thumb bow renders the bow more ergonomic the force applied to r or oppose forces of
the remaining four fingers are still primarily supplied by the thumb.
U.S. Patent 4, 635, 363 to Chapin discloses hand-operated cutting tool that includes a
ring having a central axis A offset from the central plane or axis B by an angle less than 45°.
As with the previous shears, while more mic than other designs, continues to rely on the
flexing of the thumb to oppose the forces applied by the other fingers.
U.S. Published Patent Application 2011/0131813 to Lin discloses a grip structure for a
pair of scissors. The upper grip portion for receiving the thumb is configured to support a
portion of the base of the thumb and configured to receive the thumb at an e angle with
respect to the blades, as in the previous designs. The design is primarily intended to provide
ed stability during opening or g of the scissors by avoiding undesired deflection
of the two blades of the scissors and keeping the two blades in the best al state during the
cutting process effectively improving the cutting quality and safety.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide a cutting tool, such as scissors,
snips or shears that overcomes the inherent disadvantages in most ng cutting tools.
It is another object of the invention to provide a cutting tool that is easy and
convenient to use.
It is still another object of the invention to e a cutting tool to enhance lever
power for operating the tool and, at the same time, facilitate the operation and increase the
comfort to the user.
It is yet another object of the invention to provide a g tool that enables a user to
cut thicker or harder als with less stress on the hand, and particularly the thumb.
It is a r object of the invention to provide a cutting tool of the type under
discussion that is easy to manipulate.
It is still a further object of the invention to provide a cutting tool as aforementioned
that can be used for longer periods of time and with less fatigue to the operator.
It is yet a further object of the invention to provide a cutting tool that is ergonomically
designed that is not only comfortable to use but increases the ion and control over the
cutting operation.
In order to achieve the above objects, as well as others that will become evident
hereinafter, a gripping structure for a pair of scissors or shears in accordance with the
invention comprises two levers pivotably connected at a pivot point and form substantially
el blades at distal ends of said levers. The blades define a medial cutting plane and are
pivotably movable about said pivot point between open and closed positions within said
cutting plane and, in a closed position, define a line or udinal axis with said pivot point.
Each lever is formed at a proximal end relative to said pivot point with a finger grip, a first
finger grip being a superior or an upper finger grip formed above said line or axis and having
a lower portion formed with a ntially flat inner surface closest to and extending
longitudinally along a direction generally parallel to said line or axis in said closed position
of said blades and arranged in a transverse plane substantially normal to said cutting plane.
The upper finger grip is dimensioned and configured to enable substantially full ion of
a thumb metacarpal bone from a right lateral side through said upper finger grip for receiving
the ball of the thumb to enable the thumb to be moved to a position on a left lateral side to an
orientation substantially parallel to said g plane and to position the hand’s thenar
eminence into abutment against said generally flat inner surface of said first finger grip while
positioning at least exterior right lateral portions of said loop in abutment or contact with the
palm of the hand beyond the hand’s thenar crease and into the region of at least one of the
hand’s palmar creases. A second finger grip, a lower finger grip, is positioned below said first
finger grip and configured and dimensioned to be gripped by at least some of the other four
s of the hand. In this way, the first finger grip enables the thenar eminence and palm of
the hand to oppose the forces applied by the fingers acting on said second finger grip, and
forces applied against the thenar eminence are uniformly applied against the thenar muscles
and transferred to the hand’s palmer e to enable the thumb to guide the direction of
g while minimally applying flexing or gripping forces in tion to forces applied
by the other fingers on said second finger grip to thereby ate or minimize stress or
fatigue of the thumb’s flexar muscles.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other s, es and advantages of the present invention will be
more apparent from the following ption when taken in conjunction with the
accompanying drawings, in which:
Fig. 1 is a left perspective view of a scissors or shears in accordance with the invention,
shown in a fully closed condition;
Fig. 2 is a left lateral side view of the scissors or shears shown in Fig. 1, g in
phantom outline the positions of the fingers of the hand during normal use;
Fig. 3 is similar to Fig. 2 when the scissors or shears are in a partially open condition;
Fig. 4 is a top plan view of the scissors or shears shown in Figs. 1-3;
Fig. 5 is a bottom plan view of the scissors or shears shown in Figs. 1-4, showing in
phantom outline the position of the hand during initial insertion of the thumb and prior to
gripping of the handles;
Fig. 6 is an enlarged fragmented view, as viewed from the right lateral side to show
details of the configuration of the upper finger grip;
Fig. 7 is a sectional view of the upper finger grip shown in Fig. 6, taken along
line 7-7;
Fig. 8 is a bottom plan view of the scissors or shears shown in the previous Figures,
broken away to illustrate the lower configuration of the upper finger grip and the manner that
it is arranged in relation to the thenar eminence and the palmer surfaces of the hand;
Fig. 9 is similar to Fig. 2 and shows another embodiment of a shears in which both
finger grips are angularly offset from the axis to position both grips above the axis;
Fig. 10 is r to Figs. 2 and 9 and shows still a further embodiment of a shears in
which both finger grips are linearly offset from the axis to position both grips above the axis;
Fig. 11 is a cross-sectional view of the finger grips shown in Fig. 2 taken along line 11-
DETAILED PTION
Referring now specifically to the Figures, in which identical or similar parts are
designated by the same reference ls throughout, and first referring to Fig. 1, a scissors,
, snips or other like cutting instrument is generally designated by the reference 10. All
such cutting tools will be tively referred to herein as “shears”.
The shears 10 includes two levers 12, 14 connected to each other at a pivot 16 forming
a pivot point. The levers form substantially parallel blades 12a, 14a. The blades 12, 14 define
a medial cutting plane CP and are pivotably movable about the pivot 16 between open and
closed positions within the cutting plane. In a closed position, the blades 12, 14 define a line
or longitudinal axis A with the pivot 16.
Each lever is formed at a proximal end relative to the pivot 16 with a finger grip. A first
finger grip 12b is a superior or an upper finger grip formed above the line or axis A. The first
or upper finger grip is formed above the line or axis A and has a lower portion 12c formed with
a substantially flat inner surface 12d closest to and extending longitudinally along a direction
generally parallel to the line or axis A when the blades are closed.
The first or upper finger grip 12b is dimensioned and configured to enable ntially
full insertion of a thumb metacarpal bone from a right lateral side through the upper finger grip
12b for receiving the ball of the thumb or thenar eminence (TE), as best shown in Figs. 5 and
8 from a right lateral side through the finger grip 12(b) and for receiving the ball of the thumb
to enable the thumb to be moved to a position on the left lateral side to an orientation
substantially parallel to the cutting plane CP and to position the hands’ thenar eminence TE
into abutment t the lly flat inner surface 12d of the upper finger grip 12b while
positioning at least the exterior right lateral portion 12e of the finger grip into abutment or
contact with the palm P of the hand, as best shown in Fig. 8 beyond the hand’s thenar crease
TC and into the region of at least one of the hand’s palmar s PC1 and PC2.
The second or lower finger grip 14b, in the embodiment shown in Figs. 1-8, is arranged
below the line or axis A and is configured and dimensioned to be gripped by the other four
fingers or at least some of the other four fingers of the hand as shown in Figs. 2 and 3. However,
the positions of the finger grips relative to the axis A is not critical and can be angularly or
linearly offset from the axis. See, for example, Fig. 9 in which both finger grips are angularly
offset from the axis to on both finger grips above the axis, and Fig. 10 in which both
finger grips are linearly offset from the axis to again position both finger grips above the axis.
The offsets can also on the finger grips below the axis and can result from offsets opposite
from the ones shown in Figs. 9 and 10, and can also include combinations of linear and angular
offsets.
The first or upper finger grip 12b is configured as an r loop preferably formed
with a recessed curved surface 12f the at the leading or distal end that is a continuation of the
flat inner surface 12d, on the left lateral side, to accommodate the thenar webspace or skin web
between the thumb and the index finger, when the thumb is substantially aligned with the
blades 12a, 14a.
Referring to Fig. 4, the upper finger grip 12b defines a central axis A’ that diverges or
is angularly offset from the cutting plane CP or the axis A at an angle ϴ that is within the range
of 50°-60°. Preferably, the angle ϴ is equal to approximately 55°.
The inner surface 12d is substantially flat, as shown in Fig. 11, to distribute the forces
uniformly across the thenar eminence or the ball of the thumb and the thenar muscles. Without
having any meaningful curvature or peaks in this surface 12d force concentrations on the thenar
s are avoided, preventing potentially significant pain to the user. Also, in order to render
the tool more mic and comfortable to use the flat surface 12d may be somewhat ed
upwardly from the right lateral side towards the left lateral side to conform to the shape of the
hand while in gripping engagement with the upper finger grip 12b. The inclination of the flat
surface is best shown in Fig. 11 where the surface is shown inclined downwardly from the left
to the right side relative to a plane NP substantially normal to the cutting plane CP. The
inclination angle γ is within the range of 10°-20° and, preferably within the range 15°-17°.
In preparation for use of the shears, referring to Fig. 5, the thumb is fully inserted into
the upper finger grip 12b so that the thenar eminence TE rests upon the substantially flat surface
12d and the thumb can be moved to the position shown in Fig. 8 where the thumb is
substantially aligned with the blades 12a, 14a. Once the fingers are flexed to gripping positions,
the right exterior lateral portion or edge 12e is placed into abutment with the palmer surface
PS, beyond the thenar crease TC and into contact with the palmar creases PC1 and/or PC2.
Importantly, the thumb, once in the position shown in Fig. 3, serves to primarily stabilize and
guide the direction of cutting while eliminating or substantially reducing the flexing forces
d by the thumb in opposition or to r the ing forces of the other four fingers
that act on the lower finger grip 14b, those forces being absorbed or countered by the palm of
the hand. Thus, the thenar muscles do not need to flex during operation of the shears but can
remain ntially nary, substantially reducing stress and strain on the thumb. The
design is not only mic but renders the shears more comfortable and easy to use while
ng fatigue especially with prolonged use or while cutting heavier materials.
While the shears 10 shown in Figs. 1-8 shows a shears in which the upper grip 12b is
generally located above the axis A and the lower grip 14b is positioned below the axis the
invention may be used with other configured shears, scissors or snips. Thus, referring to Figs.
9 and 10 other common configurations of shears are illustrated in which both the upper and
lower grips are positioned above the axis A. In all cases the configuration aforementioned for
the upper grip 12b is substantially the same.
The foregoing is considered as illustrative only of the ples of the invention.
Further, since numerous modifications and changes will readily occur to those skilled in the
art, it is not desired to limit the invention to the exact construction and operation shown and
described, and accordingly, all suitable modifications and lents may be resorted to,
falling within the scope of the invention.
Claims (20)
1. Shears for ng stress on a thumb of a user during ion of the shears, comprising: a first lever and a second lever pivotally connected to the first lever at a pivot, wherein each lever is pivotable from an open position to a closed on, a blade is formed on each lever, wherein the blades in the closed position define a longitudinal axis; and a first finger grip formed on the first lever, and a second finger grip formed on the second lever, wherein the first finger grip comprises a substantially flat inner surface adapted to receive a thenar eminence of the thumb of the user, and the second finger grip defines a second inner surface adapted to receive at least one finger of the user, such that combined pressure of the thenar eminence against the substantially flat inner surface and the at least one finger against the second inner e urges the first lever and the second lever to their corresponding closed positions; n both the ntially flat inner surface and the second inner surface are positioned on a same side of the longitudinal axis.
2. The shears of claim 1 wherein the first finger grip defines a first opening adapted to allow the thumb to extend h the first opening such that the thenar surface of the thumb is positioned at the substantially flat inner surface during operation.
3. The shears of claim 2 wherein the first opening is formed by an annular loop of the first finger grip, and the substantially flat inner surface is formed on the r loop.
4. The shears of claim 3 wherein the first finger grip further comprises an exterior right lateral portion which is adapted to abut against a palm of a hand of the user, beyond a thenar crease of the hand toward a palmar crease of the hand.
5. The shears of claim 2 wherein the first finger grip further comprises a lower portion, where the substantially flat inner surface is formed from the lower portion, and the second finger grip comprises a second inner surface, wherein the substantially flat inner surface and the second inner surface are generally parallel to one another when the first lever and the second lever are moved to their closed positions.
6. The shears of claim 3 wherein the first finger grip has a recessed curved surface adapted to receive a web of the hand between the thumb and an index finger during ion of the shears.
7. The shears of claim 2 wherein the closed position of the first lever and the closed position of the second lever are defined by abutment of the first finger grip t the second finger grip.
8. The shears of claim 2 n the opening allows for insertion of the rpal bone of the thumb through the opening.
9. The shears of claim 2 wherein the second finger grip defines a second opening adapted to allow at least one finger to extend through the second opening and be positioned on a second inner surface during operation of the shears.
10. The shears of claim 9 wherein a second inner surface is formed as part of a second r loop.
11. The shears of claim 1 wherein the first finger grip extends from the longitudinal axis at an angle within a range of 50° to 60°.
12. The shears of claim 2 wherein the first finger grip further comprises a flat bottom e, and the substantially flat inner surface of the first finger grip is inclined at an inclination angle with respect to the flat bottom surface.
13. The shears of claim 12 wherein the inclination angle is 10°-20°.
14. The shears of claim 13 wherein the inclination angle is 15°-17°.
15. Shears for reducing stress on a thumb of a user during operation of the shears, comprising: a first lever and a second lever pivotally connected to the first lever at a pivot, wherein each lever is pivotable from an open position to a closed position, a blade is formed on each lever, wherein the blades in the closed position define a longitudinal axis; a first finger grip formed on the first lever, and a second finger grip formed on the second lever, wherein the first finger grip comprises a substantially flat inner surface d to receive a thenar eminence of the thumb of the user, and the second finger grip defines a second inner surface d to receive at least one finger of the user, such that combined pressure of the thenar ce against the substantially flat inner surface and the at least one finger against the second inner surface urges the first lever and the second lever to their corresponding closed positions; wherein both the substantially flat inner surface and the second inner surface are oned on a same side of the longitudinal axis; and wherein the first finger grip further comprises a lower portion, where the substantially flat inner surface is formed from the lower portion, and the second finger grip comprises a second inner surface, wherein the substantially flat inner surface and the second inner surface are generally parallel to one another when the first lever and the second lever are moved to their closed positions.
16. The shears of claim 15 wherein the first finger grip defines a first g adapted to allow the thumb to extend h the first opening such that the thenar surface of the thumb is positioned at the ntially flat inner surface during operation; and the second finger grip defines a second opening adapted to allow at least one finger to extend through the second opening and be positioned on a second inner surface during operation of the shears.
17. The shears of claim 16 wherein the first opening is formed by an r loop of the first finger grip, and the substantially flat inner surface is formed on the annular loop; the first finger grip further comprises an exterior right lateral portion which is adapted to abut against a palm of a hand of the user, beyond a thenar crease of the hand toward a palmar crease of the hand; the first finger grip further comprises a lower portion, where the substantially flat inner surface is formed from the lower portion, and the second finger grip comprises a second inner surface, wherein the substantially flat inner surface and the second inner surface are generally parallel to one another when the first lever and the second lever are moved to their closed positions; and the first finger grip has a recessed curved surface adapted to receive a web of the hand n the thumb and an index finger during operation of the shears.
18. The shears of claim 17 wherein the second finger grip defines a second opening adapted to allow at least one finger to extend through the second opening and be positioned on a second inner surface during operation of the shears, and a second inner surface is formed as part of a second annular loop.
19. The shears of claim 17 wherein the first finger grip extends from the longitudinal axis at an angle within a range of 50° to 60°.
20. The shears of claim 17 wherein the first finger grip further comprises a flat bottom surface, and the ntially flat inner surface of the first finger grip is ed at an inclination angle with respect to the flat bottom surface.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US17/184,935 | 2021-02-25 | ||
US17/674,735 | 2022-02-17 |
Publications (1)
Publication Number | Publication Date |
---|---|
NZ785566A true NZ785566A (en) | 2022-03-25 |
Family
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