Note: Descriptions are shown in the official language in which they were submitted.
CA 02538325 1999-03-26
WRITING INSTRUMENT WITH FINGER GRIPPING DEVICE
Technical Field
The present invention relates generally to writing instruments such as ink
pens,
pencils, felt tip markers and the like. More specifically, this invention
relates to a writing
instrument having a gripping device thereon.
Background of the Invention
Handwriting remains an important and useful skill and manual writing
instruments
remain important tools. Most writing instruments include an elongated tube
containing a
writing medium, such as ink or pencil lead, or highlighting medium, such as
yellow, green
and pink highlighters or the likes, and having an end at which the~writing or
highlighting
medium is exposed for contact with the writing surface, such as paper. The
elongated tube
section of the writing instrument, which is grasped and held by the user when
writing, is
ch~acterized typically by a smooth, exterior surface. The smooth surface may
be attractive
and pleasant to the touch, but it can be become slippery during use resulting
in writer
discomfort and impaired legibility of the handwritten text produced.
Devices are known in the prior art to assist a user in manually gripping a
writing
instrument. U.S. patent Nos. 4,601,598 to Schwartz et al., 5,468,083 to
Chesar, 4,167,347
2 0 to Hoyle, and 4,932,800 to Lin et al. illustrate pen or pencil attachment
devices which may
be attached to the writing instrument in an attempt to reduce writer
discomfort, cramp and
fatigue. These writing aids are typically structures designed to fit over the
exterior of a
writing instrument. These independent structures which are slid onto the
exterior of the
instrument tend to be bulky and thick, and create a non-uniform surface
constraining the
2 5 user to hold the writing instrument in a fixed position.
Other structures have contoured grip surfaces constituting complex molded
surfaces
aimed at approximating the anatomical contours of a writer's fingertips during
grasping of
the writing instrument. However, the grip surfaces are not able to match the
differing
anatomical shapes and pen grasping techniques of different individuals. U.S.
Patent No.
3 0 5,221,152 to Chuang discloses a writing instrument having a gripping
segment on a section
of the pen, which screws onto a portion of a main body of the writing
instrument. The
gripping segment comprises a number of annular slip-preventing grooves axially
disposed
CA 02538325 1999-03-26
on its outer peripheral surface to help retain the instrument to the material
or surface it is
clipped to. It is not concerned with providing comfort and ease to the user of
the instrument
when writing.
U.5. Patent No. 5,000,599 to McCall et al. discloses a writing instrument
having a
deformable gripping portion, which deforms in response to manual pressure
during manual
grasping of the instrument to permit reshaping of the gripping portion from an
initial shape
to a custom fit shape generally conforming to the writer's fingertips. The
gripping portion
retains the custom fit shape for a short period after release and returns
substantially to its
initial shape. During operation, the gripping portion requires pressure to be
applied at the
onset to conform the gripping portion to the shape desired by the user.
Thus, there remains a need to provide a gripping surface for a writing
instrument
which is consistent and uniform with the surface of the writing 'instrument,
is comfortable
and easy to use, provides a firm grip and does not require excessive pressure
to conform the
shape desired by the user.
Summary of the Invention
These objects and advantages as well as other objects and advantages are
accomplished in a writing instrument including an elongated cylindrical body
preferably in
the form of a cartridge element carrying a writing or highlighting medium
therein and
2 0 having a writing tip exposed at one end. The cartridge element is
insertable into a barrel
member and may be permanently bonded to the barrel or releasably attached so
that a
replacement cartridge may be inserted into the barrel member when the writing
or
highlighting medium therein is depleted.
In a preferred embodiment of the invention the cartridge element includes a
reduced
2 5 cross-section thereon which forms an annular recessed tapered cavity. A
gripping member is
received by the cavity. The gripping member is preferably tubular in shape and
is tapered to
follow the tapered contour of the cartridge element. The gripping member may
be
penmanently attached to the annular recessed cavity by means of co-extrusion,
two-
component injection molding, or by chemical or mechanical bonding.
3 0 ~e gripping member has a smooth surface which may include a slightly
elevated or
raised pattern thereon. Preferably, the elevated pattern may be constructed in
the form of
hexagons having sides which are contiguous with neighboring hexagonal sections
and are
- 2 -
CA 02538325 1999-03-26
interconnected so as to form a continuous lattice or pattern of hexagons on
the smooth
surface. The pattern is preferably continuous over the entire smooth surface.
Moreover, the
pattern may be formed from shapes which are not connected, but which are
disposed
throughout the smooth surface.
The elevated pattern formed,on the smooth surface provides friction between
the
gripping section and a user's fingers, and is resiliently compressible by the
user's fingers for
an improved grip. When in use, the writing instrument is grasped by a user at
the gripping
section. The gripping section provides a soft, textured and compressible
surface which is
comfortable to the touch and is not prone to slippage between the user's thumb
and fingers.
Since the gripping surface is penmanently attached to the body of the pen, the
possibility of
having the gripping member becoming loose during use is greatly reduced. In
another
aspect of the invention, a cap may be provided on the cartridge element and
fitted over the
gripping member and the~writing tip to cover same.
Brief Description of the Drawings
Features of the present invention are disclosed in the accompanying drawings,
wherein similar reference characters denote similar elements throughout the
several views,
and wherein:
Fig. 1 is a front view of the writing instrument of the present invention
showing the
2 0 gripping section thereon; .
Fig. 2 is a partial sectional view of the writing instrument shown in Fig. 1
illustrating the features of the gripping section;
Fig. 3 is a sectional view of the writing instrument of Fig. 1 shown with a
cap
member thereon;
2 5 Fig. 4 is a front view of the writing instrument shown in Fig. 1 with the
cap
member;
Fig. 5 is a cross-sectional view of the cap member; and
Fig. 6 is a top view of the cap member.
3 0 Detailed Description of the Invention
Turning to Figs. 1 through 3, an embodiment of a writing instrument 10
constructed
in accordance with the present invention is shown with the understanding that
those of
- 3 -
CA 02538325 1999-03-26
ordinary skill in the art will recognize many modifications and substitutions
which may be
made to various elements.
Writing instrument 10 generally includes an elongated cylindrical body 12
preferably in the form of a cartridge element carrying a writing or
highlighting medium
therein and having a writing tip 14 exposed at one end of the cartridge
element. Cartridge
element 12 is insertable into a barrel member 13 and may be permanently bonded
thereto or
releasably attached so that a replacement may be inserted into barrel member
13 when the
writing highlighting medium therein is depleted. Methods of attachment include
but are not
limited to press fitting, snap fitting, chemical bonding and ultrasonic
bonding.
Additionally, it is preferred that cartridge element 12 comprises threads 21,
as shown in Fig.
2, configured and dimensioned to be received by corresponding internal threads
22 defined
on the inside of barrel 13, as shown in Fig. 3, so that barrel 13
and~cartridge element 12 can
be releasably attached to each other. Writing instrument 10 may also include a
writing or
highlighting medium that is retractable with respect to cartridge element 12,
so that the
sting or highlighting medium may be selectively positioned outside cartridge
12 when
writing is desired and be retracted into cartridge 12 for storage and
transport.
In a preferred embodiment of the invention and as depicted in Fig.2, cartridge
element 12 includes a reduced cross-section, which forms an annular recessed
tapered
cavity 15. Gripping member 16 is received in cavity 15 and is flush with a
stepped member
17 on body 12. As shown stepped member 17 has a diameter that is slightly less
than the
diameter of section 19 of body 12, such that section 19 can facilitate the
insertion of a cap
member, as discussed below. Preferably, gripping member 16 is suitably
dimensioned and
shaped to fit smoothly within recess 15 of cartridge element 12. Gripping
member 16 is
also preferably tubular in shape and is tapered to follow the tapered contour
of cartridge
2 5 element 12. Thus, as will be appreciated, a tubular gripping member 16
preferably has a
smooth interior surface to fit smoothly within recess 15 as illustrated in
Fig. 2. Preferably,
gripping member 16 is fabricated of a thermoplastic elastomer, including but
not limited to
polypropylene, rubber, polyurethane, polyisobutylene, polybutadiene. Moreover,
in order
to provide comfort and ease during operation of the writing instrument, it is
important that
3 0 gripping member 16 be of a suitable softness, preferably softer than the
cartridge element
12. Preferably, the hardness of the material of gripping member 16 is in the
range of Shore
A hardness of 3 to 40 durometer, and more preferably in the range of 3 to 25
durometer, and
- 4 -
CA 02538325 1999-03-26
most preferably in the range of 3 to 15 durometers. However, the gripping
member may
also have a hardness of less than 3 durometer.
10
20
30
- 4g -
CA 02538325 1999-03-26
Gripping member 16 is adhered to cartridge element 12 by kinetic, ultrasonic
or
laser welding. Alternative methods of adhering gripping member 16 to cartridge
element 12
include but are not limited to solvent bonding and co-injection molding. The
gripping
member and the cartridge element may also be manufactured by a two-component
injection
molding process, which produces a chemical bond between these two members.
Gripping member 16 has a smooth surface 18 which may include a slightly
elevated
or raised pattern thereon. Preferably, the pattern comprises a plurality of
slightly elevated
sections 20. As shown in Fig. 1, elevated sections 20 are in the form of
hexagons having
sides which are contiguous with neighboring hexagonal sections and
interconnected so as to
form a continuous lattice or pattern of hexagons on smooth surface 18. The
pattern is
preferably continuous over the entire smooth surface 18. The elevated pattern
20, which
preferably has less surface area than the smooth surface 18, is resiliently
deformable by the
user's fingers, so that additional traction between the gripping member and
the user's fingers
is provided in addition to the friction between the gripping member and the
user's fingers.
Moreover, the pattern may be formed of shapes which are not connected, but
which are
disposed continuously throughout smooth surface 18.
When in use, the writing instrument is grasped by a user at the gripping
section.
The gripping section provides a soft, textured surface which is resiliently
deformable and is
therefore not prone to slippage between the user's thumb and fingers. Since
the gripping
2 0 surface is permanently attached to the body of the pen the possibility of
having the gripping
member becoming loose during use is greatly reduced. The thickness of gripping
member
16 is preferably in the range of 0.50 to 2.0 mm as measured from smooth
surface 18 to
elevated sections 20. The elevated pattern 20 is preferably in the range of
0.1 to 0.5 mm as
measured from smooth surface 18.
2 5 As shown in Fig. 3, another aspect of the invention includes a cap 24
provided on
cartridge element 12, which is dimensioned to fit over at least a portion of
gripping member
16 and writing tip 14 to cover same. Preferably, cap 24 cooperates with raised
section 19 to
ensure a tight connection between cap 24 and cartridge 12. Gripping member 16
is of
sufficient size, shape and thickness to provide a comfortable, flexible
surface having anti-
3 0 slip properties. It is not bulky to grip, is able to fit neatly on
cartridge 12 and can be easily
covered by cap 24.
- 5 -
CA 02538325 1999-03-26
Referring to Figs. 4-6, writing instrument 10 is shown with cap member 24. Cap
24
is configured and dimensioned to be releasably attached to cartridge element
12. Cap 24
protects writing tip 14 when the writing instrument 10 is not in use, and it
also isolates the
ink from writing tip 14 from contaminating the surrounding areas. Cap 24
comprises a
hollow body 26 defining an open end, clip member 28, vented plug 30 and well
32. When
not in used writing tip 14 is inserted into well 32, which is preferably
attached to vented
plug 30 by snap fitting, threading, chemical bonding or ultrasonic bonding.
Well 32 can
also be formed integrally with vented plug 30. Plug 30 defines a plurality of
apertures 34
therein such that air communication is established between the interior of cap
24 and the
outside environment through plug 30.
The writing instrument of the present invention may be manufactured by
providing a
cartridge element having a writing or highlighting medium therein and a
writing tip thereon.
A tubular shaped gripping member is provided and is adhered to the cartridge
element by a
two-step injection molding process to chemically bond the gripping member to
the cartridge
element. Alternatively, the gripping member may be mechanically bonded to the
cartridge
element by laser or ultrasonically welding or solvent bonding the member to
the cartridge
element.
While various descriptions of the present invention are described above, it
should be
understood that the various features can be used singly or in any combination
thereof.
2 0 ~erefore, this invention is not to be limited to only the specifically
preferred embodiments
depicted herein.
Further, it should be understood that variations and modifications within the
spirit
and scope of the invention may occur to those skilled in the art to which the
invention
pertains. Accordingly, all expedient modifications readily attainable by one
versed in the
2 5 ~ from the disclosure set forth herein that are within the scope and
spirit of the present
invention are to be included as further embodiments of the present invention.
The scope of
the present invention is accordingly defined as set forth in the appended
claims.
- 6 -
