Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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An Improved Lever Bar
FIELD OF THE INVENTION
[001] The invention relates generally to levers and crowbars but more
particularly to an improved lever bar for removing metal forms used in
construction.
BACKGROUND OF THE INVENTION
[002] The lever and its principle is one of the first tools used by man. The
basic principle of leverage has been used in ancient times from building
the Egyptian pyramids, Roman structures, Medieval buildings etc. and
continues to be used in modem day construction.
[003] There exist a variety of levers which fulfill varying functions. Lever
bars
are a basic tool used in building and demolition and its design, weight
and strength often defines the number of applications it can take on.
[004] Starting from the simple straight metal lever with a flattened end to
ones
with pivotable and interchangeable heads, there exist a choice of lever
bars also called crow bars, pinch bars, timber bars, pry bars, claw
hammers and the like.
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[005] Some levers are designed for a number of needs while the more simple
designs often serve a more specific need. Construction workers often
choose the one that is more suited to their needs while considering
comfort, strength and ease of use.
[006] In order to remove metal forms from buildings, current lever bars fall
short in two respects, they either do not possess the correct angle for
removing metal forms easily or they lack the strength due to movable
joints, two part construction and/or pivotable heads.
[007] The current invention addresses the need for an easier, stronger and
more efficient lever which is more specifically designed to remove metal
forms and brackets besides performing other routine tasks such as
removing nails, prying floorboards,wedging, hammering, moving heavy
objects etc.
SUMMARY OF THE INVENTION
[008] In view of the foregoing disadvantages inherent in the known devices
now present in the prior art, the present invention, which will be
described subsequently in greater detail, is to provide objects and
advantages which are:
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[009] To provide for a lever bar with a curved double sided head at one end
and a flattened point at the other end. The curved head is crescent
shaped and angled to the straight metal shaft or handle in such a way
that it provides for two lever heads with different operating angles. The
ends of these two heads are flattened and claw shaped respectively.
The claws are used to pull or extrude nails and screws from forms,
boards, beams, floorboards or other surfaces that it is used upon.
[0010] Another advantage of this invention is that it is constructed or
moulded
from one piece of metal with reinforcements strengthening the areas
which are subject to maximum stress. This makes the lever bar
extremely durable and able to lift heavier loads as compared to most
lever bars available today.
[0011] The two angles on the double sided curved head are conceived to be
most effective for removing metal forms and brackets which are often
located at a higher elevation. Besides metal forms the two angles of the
curved head are ideal to lift and move heavy objects about. To lift or
move a heavy object such as a garbage dumpster for example, one
inserts one end of the curved head under the dumpster. Depending on
the lift height and/or comfort desired, one chooses one of the two angles
most suited. The handle of the lever is then pressed or leveraged much
as one would use a regular lever, thereby lifting the dumpster.
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[0012] Similarly for removing metal forms and brackets, the nails can first be
removed using the claws on either of the curved heads. Thereafter, one
chooses the curved head with the angle best suited to the part of the
form one wishes to pull. Inserting the flat end into the gaps, one is able
to pull the form off the surface it is attached to with considerable ease
also aided by its long handle. If one requires the traditional straight crow
bar for certain functions or positions, the lever bar is simply reversed so
as to use the flattened end at the other end of the lever bar.
[0013] More specifically, the improved lever bar is comprised of an elongated
shaft having two opposite distal ends; the first of the two opposite distal
ends includes a crescent shaped portion having opposite end portions,
both of the crescent opposite end portions respectively include flattened,
clawed portions; and the second of the two opposite distal ends includes
a flattened, pointed portion.
[0014] In a preferred embodiment, the central focal radial axis of the
crescent
shaped portion is formed at an angle with respect to the linear axis of
the elongated shaft, such that operating angles formed between
respective tangential axes of the crescent end portions and the linear
axis of the elongated shaft are different and thereby offer different
operating angles for different mechanical leverages and purposes.
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[0015] The lever bar further includes an angled neck portion connecting a base
portion of the crescent shaped portion to a lower neck portion of the
elongated shaft and thereby forming the angle between the central focal
radial axis of the crescent shaped with respect to the linear axis of the
5 elongated shaft.
[0016] An elongated reinforcement member is attached to the lower neck
portion, to the angled neck portion, and to the base portion of the
crescent shaped portion in an elongated and contiguous form to thereby
increase the overall strength of the lever bar and thereby withstand the
increased stresses on the portions when the lever bar is in use.
[0017] The material used to form the lever bar is chosen from a group
including
iron, steel, polycarbonate, fiberglass, composites, and ceramics.
[0018] The lever bar can be formed from a single mould technique.
[0019] The lever bar has its flattened, clawed portions, and flattened,
pointed
portion further hardened using methods that include heating and
tempering techniques.
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[0020] There has thus been outlined, rather broadly, the more important
features of the invention in order that the detailed description thereof
that follows may be better understood, and in order that the present
contribution to the art may be better appreciated. There are additional
features of the invention that will be described hereinafter and which will
form the subject matter of the claims appended hereto.
[0021] In this respect, 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 to the arrangements
of the components set forth in the following description or illustrated in
the drawings. The invention is capable of other embodiments and of
being practiced and carried out in various ways. Also, it is to be
understood that the phraseology and terminology employed herein are
for the purpose of description and should not be regarded as limiting.
[0022] As such, those skilled in the art will appreciate that the conception,
upon
which this disclosure is based, may readily be utilized as a basis for the
designing of other structures, methods and systems for carrying out the
several purposes of the present invention. It is important, therefore, that
the claims be regarded as including such equivalent constructions
insofar as they do not depart from the spirit and scope of the present
invention.
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[0023] These together with other objects of the invention, along with the
various
features of novelty which characterize the invention, are pointed out with
particularity in the claims annexed to and forming a part of this
disclosure. For a better understanding of the invention, its operating
advantages and the specific objects attained by its uses, reference
should be made to the accompanying drawings and descriptive matter
which contains illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Fig. I Side view of the invention.
[0025] Fig. 2 Isometric view of the invention.
[0026] Fig. 3 View of the invention on its side.
[0027] Fig. 4 Side view of the invention.
[0028] Fig. 5 Top plan view of the curved head the handle being omitted.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
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[0029] An improved lever bar (10) has an elongated shaft (12) having two
opposite distal ends The first of those two opposite distal ends includes
a crescent shaped portion (14) which has opposite end portions. Both of
the crescent opposite end portions respectively include clawed portions
(18, 20) which are flattened to gain easy access to small gaps and
clawed ( as seen in fig.2, flg.3 and fig.5) to be able to pull out nails,
screws etc. (not shown). The second of the two opposite distal ends
includes a flattened, pointed tip (16). The flattened pointed tip (16)
serves as a normal straight crow bar along with the handle (12).
[0030] The central focal radial axis of the crescent shaped portion (14) is
formed at an angle with respect to the linear axis of the elongated shaft
(12) such that operating angles formed between respective tangential
axes of the crescent shaped portion (14) and the linear axis of the
elongated shaft (12) are different and thereby offer different operating
angles for different mechanical leverages and purposes such as for
removing metal forms (not shown) from building walls, ceilings and other
surfaces (not shown).
[0031] The lever bar (10) further includes an angled neck portion (24)
connecting a base portion (22) of the crescent shaped portion (14) to a
lower neck portion (26) of the elongated shaft (12) and thereby forming
the angle between the central focal radial axis of the crescent shaped
portion (14) with respect to the linear axis of the elongated shaft (12).
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[0032] An elongated reinforcement member (28) is attached to the lower neck
portion (24), and to the base portion (22).
[0033] The material used to form the lever bar (10) is chosen from a group
including iron, steel, polycarbonate, fiberglass, composites, and
ceramics. Additionally, the lever bar (10) can be formed from a single
mould technique.
[0034] The lever bar (10) has its flattened, clawed portions, and flattened,
pointed portion further hardened using methods that include heating and
tempering techniques.
[0035] When in use, depending on the angle and access available, one of
either clawed portions (18) and (20) can be chosen. With its flattened
end inserted into the gaps between the forms (not shown) and the
handle (12) pulled and/or leveraged to remove the forms (not shown)
from the surface (not shown) it is adhering to.
[0036] Nails and screws (not shown) can also be removed using the clawed
portions (18) and (20) during the process. The elongated shaft (12)
allows one easy reach to the metal forms (not shown) which are often
located high and close to ceilings of buildings.
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[0037] As to a further discussion of the manner of usage and operation of the
present invention, the same should be apparent from the above
description. Accordingly, no further discussion relating to the manner of
usage and operation will be provided.
5 [0038] With respect to the above description then, it is to be realized that
the
optimum dimensional relationships for the parts of the invention, to
include variations in size, materials, shape, form, function and manner of
operation, assembly and use, are deemed readily apparent and obvious
to one skilled in the art, and all equivalent relationships to those
10 illustrated in the drawings and described in the specification are
intended to be encompassed by the present invention. Therefore, the
foregoing is considered as illustrative only of the principles 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 equivalents may be
resorted to, falling within the scope of the invention.