U.S. patent application number 09/919615 was filed with the patent office on 2003-02-06 for snow removal tool having an insert-molded wearstrip and method of forming same.
Invention is credited to Parker, Thomas, Schultice, Jan E..
Application Number | 20030025344 09/919615 |
Document ID | / |
Family ID | 25442370 |
Filed Date | 2003-02-06 |
United States Patent
Application |
20030025344 |
Kind Code |
A1 |
Schultice, Jan E. ; et
al. |
February 6, 2003 |
Snow removal tool having an insert-molded wearstrip and method of
forming same
Abstract
An snow removal tool having an insert-molded wearstrip is
disclosed. According to one embodiment of the present invention,
the tool includes: a plastic blade portion and a wearstrip attached
to each other by insert molding. Insert molding is performed by
placing the wearstrip, which has one or more openings therethrough,
in a recess of a mold cavity. Plastic is injected into the mold
cavity and flows through the openings in the wearstrip. Upon
solidification of the plastic, the final molded product has a
cutting edge of the wearstrip protruding from a front edge of said
snowtool. Preferably the wearstrip is made from galvanized steel
and has a fold or ridge across it to increase stiffness of said
snowtool in bending.
Inventors: |
Schultice, Jan E.;
(Senecaville, OH) ; Parker, Thomas; (Columbus,
OH) |
Correspondence
Address: |
BROBECK, PHLEGER & HARRISON, LLP
ATTN: INTELLECTUAL PROPERTY DEPARTMENT
1333 H STREET, N.W. SUITE 800
WASHINGTON
DC
20005
US
|
Family ID: |
25442370 |
Appl. No.: |
09/919615 |
Filed: |
August 1, 2001 |
Current U.S.
Class: |
294/54.5 ;
294/56 |
Current CPC
Class: |
E01H 5/02 20130101 |
Class at
Publication: |
294/54.5 ;
294/56 |
International
Class: |
E01H 005/02 |
Claims
We claim:
1. A tool apparatus comprising: a blade; and a wearstrip attached
to said blade by insert molding.
2. The apparatus of claim 1, further comprising: a shaft coupled to
said blade; and a handle coupled to said shaft.
3. The apparatus of claim 1, wherein said wearstrip comprises at
lest one perforation.
4. The apparatus of claim 3, wherein said blade comprises a
moldable material that fills said one or more openings during
insert molding.
5. The apparatus of claim 4, wherein said moldable material is
plastic.
6. The apparatus of claim 1, wherein said wearstrip is
L-shaped.
7. The apparatus of claim 1, wherein said wearstrip comprises
metal.
8. The apparatus of claim 7, wherein said wearstrip comprises
galvanized steel.
9. The apparatus of claim 1, wherein the wearstrip is
scalloped.
10. The apparatus of claim 1, wherein the apparatus is a snow
removal tool.
11. A method for attaching a wearstrip to a tool blade, comprising:
placing a wearstrip comprising one or more openings therethrough in
a recess in a mold cavity of the tool blade; injecting a fluid
material into said mold cavity, wherein said fluid material flows
through said one or more openings; solidifying said fluid material
to obtain a final molded product; wherein said final molded product
has a cutting edge of said wearstrip protruding from a front edge
of said snowtool.
12. The method of claim 11, wherein said fluid material is
plastic.
13. The method of claim 11, wherein said wearstrip is metal.
14. The method of claim 11, further comprising: shaping the
wearstrip after solidification.
15. A snowtool comprising: a plastic digging end; and a wearstrip
having a first portion comprising one or more openings
therethrough; wherein said plastic digging end covers said first
portion and fills said one or more openings.
16. The snowtool of claim 15, wherein said wearstrip comprises a
second portion not in direct contact with said plastic digging
end.
17. The snowtool of claim 15, wherein said second portion has a
cutting edge.
18. The snowtool of claim 15, wherein said wearstrip is metal.
19. The snowtool of claim 18, wherein said metal is galvanized
steel.
20. The snowtool of claim 15, wherein said wearstrip comprises a
fold or ridge across it to increase stiffness of said snowtool in
bending.
Description
FIELD OF THE INVENTION
[0001] The invention relates to snow tools; in particular, it
relates to a snow removal tool having an insert-molded
wearstrip.
DESCRIPTION OF THE RELATED ART
[0002] Many snow tools, such as snow shovels and snow pushers, on
the market today are made of molded plastic. Some of these tools
feature a metal wearstrip attached to the front edge of the tool.
The function of this metal wearstrip is to reduce the wear on the
front edge of the tool as it is used on abrasive surfaces such as
asphalt and concrete. In addition, the metal wearstrip can provide
a sharper cutting edge which allows snow and ice to be removed more
cleanly and completely.
[0003] In general, these metal wearstrips are attached using metal
rivets. Riveting requires that holes be formed in the plastic
snowtool by drilling or molding, and carefully aligning the
wearstrip and snowtool while rivets are inserted and clinched. A
disadvantage of riveting is that riveting equipment is expensive
and the act of riveting is costly and labor intensive.
SUMMARY OF THE INVENTION
[0004] Therefore, a need has arisen for a snow removal tool having
an insert molded wearstrip that overcomes these and other
shortcomings of the related art.
[0005] It is an object of the present invention to provide a snow
tool having a wearstrip attached without using rivets or any
secondary operation performed after molding, e.g., crimping.
[0006] According to one embodiment of the present invention, a snow
tool comprises a blade portion and a wearstrip attached to each
other by insert molding. Insert molding is performed by placing the
wearstrip, which has one or more openings therethrough, in a recess
of a mold cavity. A polymer material is injected into the mold
cavity and flows through the openings in the wearstrip. Upon
solidification of the polymer, the final molded product has a
cutting edge of the wearstrip protruding from a front edge of said
snowtool. Preferably, the wearstrip is galvanized steel and has a
fold or ridge across it to increase stiffness of the snowtool in
bending.
[0007] It is a technical advantage of the present invention that
rivets are not required, thereby eliminating the costly and labor
intensive process of riveting. Moreover, the present invention does
not require any secondary attachment operation performed after
molding, e.g., crimping.
[0008] The foregoing, and other features and advantages of the
invention, will be apparent from the following, more particular
description of the preferred embodiments of the invention, the
accompanying drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] For a more complete understanding of the present invention,
the objects and advantages thereof, reference is now made to the
following descriptions taken in connection with the accompanying
drawings in which:
[0010] FIG. 1 depicts a snow tool comprising an insert molded metal
wearstrip according to an embodiment of the invention;
[0011] FIGS. 2(a), 2(b), and 2(c) depict, respectively, a top view,
a cross-sectional view, and an expanded cross-sectional view of the
snow tool shown in FIG. 1;
[0012] FIG. 3 illustrates a metal wearstrip according to an
embodiment of the invention; and
[0013] FIG. 4 depicts a method for forming a tool having a metal
wearstrip according to one embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0014] Preferred embodiments of the present invention and their
advantages may be understood by referring to FIGS. 1-4, like
numerals being used for like corresponding parts in the various
drawings.
[0015] Although the present invention is described in the context
of snow removal tools, the present invention is not so limited. The
inventive concept can be employed in any type of tool comprising a
wearstrip attached to moldable material.
[0016] In the preferred embodiment of the invention, a snow tool
features a wearstrip attached to the digging or pushing end (herein
referred to as the blade element) of the snow tool by means of
insert molding. Referring to FIG. 1, snow tool 100 is shown
comprising blade 110, wearstrip 120, and connector 130 for
connecting blade 110 to a shaft and handle (not shown). Blade 110
is manufactured from a material suitable for molding, such as, but
not limited to, plastic, preferably, polypropylene, high density
polyethylene ("HDPE"), acrylonitrile butadiene styrene ("ABS"),
nylon, reinforced plastic, e.g., graphite-impregnated plastic, and
the like. Wearstrip 120 is preferably metal, e.g., galvanized
steel, but can also be fashioned from any type of solid material,
e.g., ceramic, high strength polymer, or a composite material, that
will remain rigid during injection molding and has suitable
hardness for snow or ice removal.
[0017] FIG. 2(b) depicts a cross-sectional view of snow tool 100
taken along axis A-A, shown in FIG. 2(a). FIG. 2(c) portrays an
expanded view of snow tool 100 at a location where wearstrip 120
and blade 110 are joined together. Wearstrip 120 comprises one or
more openings, e.g., holes, as shown in FIG. 3, to allow blade
material to flow through during molding. Axis A-A dissects one of
these openings as shown in FIG. 2(c).
[0018] Wearstrip 120 is attached by the process commonly referred
and known in the art as insert molding. FIG. 4 depicts method 400
for forming a tool having a metal wearstrip according to one
embodiment of the present invention. Wearstrip 120 is placed (step
410) in a proper recess in an open mold cavity. The mold is closed
(step 420) and the blade material, e.g., plastic, is injected (step
430) and allowed to flow (step 440) through the openings in
wearstrip 120 and then solidify. Upon solidification of the blade
material, the molded tool is removed (step 450) from the cavity.
After molding, the cutting edge of wearstrip 120 protrudes from the
front edge of the snowtool, while a portion of wearstrip 120
remains within the snowtool at a sufficient depth to provide firm
anchoring. After molding, wearstrip 120 may be shaped, if
desired.
[0019] Whereas the wearstrip illustrated in FIGS. 1-3 is flat and
has openings, in other embodiments, wearstrip 120 may include a
fold or ridge in order to increase tool stiffness in bending. In
other embodiments, wearstrip 120 may be L-shaped, scalloped,
notched along one or more surface ends, serrated, or any
combination thereof, with or without perforations, in order to
improve anchoring within the snowtool or to assist in snow or ice
removal.
[0020] Other embodiments and uses of the invention will be apparent
to those skilled in the art from consideration of the specification
and practice of the invention disclosed herein. It is intended that
the specification and examples be considered exemplary only, with
the true scope and spirit of the invention indicated by the
following claims.
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