Note: Descriptions are shown in the official language in which they were submitted.
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TOOL BLADE
FIELD OF THE INVENTION
[1000] This invention is directed toward a tool blade that can
be used in a number of tools. The invention is more particularly
directed toward a tool blade particularly useful in tools used in
lifting or prying material from a support surface. The tool blade
can also be used to remove various fasteners holding material to
a support surface. The tool blade is particularly useful in a
roofing tool used in removing roofing material, such as asphalt
shingles, and in removing roofing material fasteners, such as
shingle nails. The tool blade can be used in tools used to remove
tiles or other floor coverings. The tool blade could be used in
tools used to renovate or demolish buildings, the blade
particularly useful in removing panels, flooring, siding, molding
and the like. The tool blade could be used in tools to remove ice
from walkways. The invention is also directed toward tools
employing the tool blade.
BACKGROUND ART
[1001] Lifting tools are known having a straight, flat, blade
at the end of a handle with the blade having a tapered front
edge. The blade can be slid under the edge of a piece or layer of
material on a flat support surface using the tapered front edge.
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The blade can extend at an angle to the handle of the tool so
that the tool can be levered by the handle about the front or
back edge of the blade to try to lift the material off the
support surface with a part of the blade under the material.
These known tools are used to lift and remove roofing materials
from roofs; floor coverings from flooring; and panels from walls,
by way of example.
[1002] Other lifting tools are known where the blade itself is
bent to form front and rear blade portions. The front of the
front portion is tapered to its front edge. The blade is levered
by the tool handle about the bend joining the front and rear
portions to lift the front of the front portion of the blade.
More leverage can be applied to the front portion of the blade by
the handle since the front portion provides a shorter lever arm
between the front edge and the bend relative to the long lever
arm provided by the handle. However, a bent or angled blade is
limited as to how far it can be inserted under the material to be
removed and thus it can take longer to remove a given amount of
material than when using a straight, flat blade.
[1003] The known tools usually have slots in the blade
extending rearwardly from at least the front edge of the blade.
The slots separate forwardly extending teeth on the blade. The
slots are used to remove material fasteners connecting the
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material, being removed, to the support surface. The slots can
receive the shanks of material fasteners, such as roofing nails,
with the heads of the fasteners resting on adjacent teeth. The
tool is operated to lever the fasteners, caught in the slots, out
of the supporting surface, the leverage applied by pivoting the
blade about either its front or rear edge.
[1004] However, the known lifting tools with straight, flat,
blades can have trouble lifting material that is tightly held on
the support surface. The known lifting tools can have particular
trouble lifting 'frozen' fasteners, fasteners that have rusted
slightly in place and/or are tightly held by dried wood. The
problem exists when lifting panels held by 'frozen' fasteners or
when trying to lift the fasteners themselves. The lifting
leverage provided by a tool with a straight blade is not always
sufficient to lift tightly held fasteners or panels held with
such fasteners. Some known roofing tools with straight blades can
be bent when trying to Lift 'frozen' fasteners thereby limiting
their use.
[1005] Also, the slots in the blades in all known lifting
tools, particularly roofing tools, are usually designed to take
one size only of a fastener. Further the slots are usually
designed to merely capture the fasteners and not help 'crack' the
fasteners from the support surface while guiding the fasteners
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into the slots. The tools are also not designed to remove
fasteners from under covers such as, for example, roof flashing.
In addition, the known lifting tools do not have handles designed
to more easily and safely lift material and/or fasteners with the
blade of the tool.
SUMMARY OF THE INVENTION
[1006] It is purpose of the present invention to provide a
lifting tool blade that can provide a strong lifting force to
provide initial movement to most tightly held material on a
support surface that is to be lifted and removed. It is a further
purpose of the present invention to provide a lifting tool blade
that can more easily lift and remove tightly held fasteners
holding material onto a support surface. It is another purpose to
provide a straight lifting tool blade that can be easily inserted
far under material to be removed. It is another purpose of the
present invention to provide a lifting tool blade with slots that
can receive different sizes of material fasteners while initially
lifting them: It is another purpose of the present invention to
provide a lifting tool blade with different teeth on the front
and back edges of the blade so the blade can be used for pulling
one type and size of material fastener with the teeth on the
front edge and for pulling another type and size of material
fastener with the teeth on the back edge. It is another purpose
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of the present invention to provide a lifting tool having means
on the blade for removing fasteners from underneath covering
material. It is another purpose of the present invention to
provide a stronger lifting tool that has a straight blade that is
not easily bent during use. It is a further purpose of the
present invention to provide a lifting tool with a handle that
can more easily and safely manipulate the blade of the tool.
[1007] In accordance with the present invention, a lifting
tool blade is provided with front and rear edges. The blade has
top and bottom surfaces joining the front and rear edges. The
bottom surface is slightly bent intermediate the front and rear
edges to form a straight, front, bottom section and a straight,
rear, bottom section joined at a~ridge. The ridge extends across
the blade and is parallel to the front edge. The front, bottom
section diverges slightly away from the top surface toward the
ridge from the front edge to form a relatively long thin wedge
shape ending in a thin front edge at the front of the blade. The
blade is thickest at the ridge and thinnest at the front edge.
Preferably, the rear, bottom section also diverges slightly away
from the top surface toward the ridge from the rear edge to form
a relatively long thin wedge shape ending in a thin front edge at
the rear of the blade. The ridge provides a fulcrum point about
where the blade can be slightly pivoted when resting on a support
surface.
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[1008] The front of the tapered front section of the blade,
when on a lifting tool, can be inserted under the edge of
material to be removed while sliding along the support surface on
the front, bottom surface section. The blade can then be pivoted
about the ridge to rest on its rear,~bottom surface section to
initially slightly lift the material to release it from its
support surface. The blade can then be further pivoted about its
front or back edges to further lift the material to loosen it for
removal. Often, a major portion of the tapered front section of
the blade can be inserted under the material to be removed if the
material is not tightly held, the blade caroming the material
upwardly to loosen it.
[1009] The front edge of the blade can have slots therein
extending rearwardly and forming teeth between them at the front
of the blade. The blade can be maneuvered to position a fastener
in a slot in the front edge of the blade, the head of the
fastener supported by the adjacent teeth. The blade is then
pushed forward riding on its front, bottom surface section. The
fastener can often be 'cracked' or raised out of the support
surface by its head being caromed up by the tapered front section
of the blade as the blade is pushed forward. If the fastener does
not move as the blade is pushed forward, the blade can be pivoted
about the ridge while the fastener is in the slot to crack the
fastener initially a short distance. The lever arm for the front,
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bottom surface section of the blade is relatively short, so
greater leverage is obtained to lift the fastener initially than
is obtained from a straight blade of uniform thickness which has
to be pivoted about the rear edge of the blade to provide
leverage. Once the fastener has moved initially, the fastener is
removed by pivoting the blade about its front or rear edges while
the fastener is in the slot.
[1010] The blade with the bottom ridge can have one set of
slots on the front edge for receiving one size of fastener and
the another set of slots on the back edge for receiving a
different size of fastener. A tool with this blade can be used
with to remove two different sizes of commonly used fasteners.
While the blade used with the two sets of slots has been
described as a blade with a bottom ridge, the blade can also be a
flat blade with no bottom ridge.
[1011] The slots between the teeth in the front or back edge
of the blade can be shaped to receive different sizes of
fasteners. Each slot can be shaped to have an outer slot section
which is quite wide initially and tapers down to the mouth of an
intermediate slot section which in turn tapers down to the mouth
of an inner slot section. The inner slot section extends to the
end of the slot. The tapered outer slot section is large so as to
be able to easily catch and direct fasteners into the slots. In
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addition, the outer slot section, with a wide taper, very
gradually engages and raises a fastener. The head of the fastener
can initially be engaged by one side of the slot only. The
portion of the teeth adjacent the intermediate slot section will
pick up the heads of the most commonly used material fasteners.
The portion of the teeth defining the narrow inner slot section
will pick up half or broken heads of common material fasteners.
The shaped slots are preferably used with a blade having a bottom
ridge but they can be used with a flat blade having no bottom
ridge.
[1012] The blade can be modified with an angled side slot
extending inwardly from at least one side of the blade. The side
slot can be located close to the front edge on the blade and can
be angled rearwardly. The front edge can be with or without
slots. A nail, under a cover, can be caught in the side slot by
sliding the blade under the cover and then drawing the blade with
its side, with the slot, against the fastener until the fastener
enters the slot. The blade can then be rotated to withdraw the
fastener. The angled side slots are preferably used with a blade
having a bottom ridge but they can also be used on flat blades
having no bottom ridge,
[1013] The blade can be strengthened, if desired, by bending
the blade at a point just behind the~front teeth to form a slight
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upstanding ridge extending across the width of the blade, the
ridge parallel with the front edge. Not only does the ridge
strengthen the blade it also helps direct material away from the
blade to help lift the material. The blade is preferably a blade
with a bottom ridge but can also be a flat blade with no bottom
ridge. The blade of the present invention can be employed on
lifting tools with a handle attached.directly to the approximate
center of the blade and extending upwardly and rearwardly or with
a handle attached to a socket on the blade, the socket extending
upwardly and rearwardly.
[1014] The lifting tool can be strengthened by including a
gusset between the top front portion of the blade and the top
front of a handle or handle socket on the top of the blade. The
gusset strengthens the blade against bending and is shaped to
direct the material upwardly as the blade is forced under the
material. The blade is preferably a blade with a bottom ridge but
can also be a flat blade with no bottom ridge. The tool can also
have a handle bent to make the tool more efficient and safe in
use.
[1015] The invention is particularly directed toward a blade
for a lifting tool having front and rear edges joined by sides, a
top surface and a bottom surface. At least the front edge is
thin. The bottom surface has a front section and a rear section.
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The front, bottom surface section extends rearwardly from the
front edge of the blade while angling slightly away from the top
surface, and the rear bottom surface section extends forwardly
from the rear edge. The front and rear sections join to define a
bottom ridge intermediate the front and rear edges of the blade.
The ridge is at the thickest portion of the blade, extends across
the blade, and is parallel to the front edge of the blade.
Preferably, the ridge is located within the middle three-fifths
of the blade between the edges.
[1016] The invention is further particularly directed toward a
blade for a lifting tool having front and rear edges, the front
portion of the blade tapered toward the front edge. The blade has
slots extending inwardly from the front edge to form outwardly
extending teeth. Each slot is defined by adjacent teeth and has
an outer section that tapers inwardly from an outer mouth to
collect and direct a nail into the slot. The slot has an
intermediate section following the outer section that tapers
inwardly, at a lesser angle than the outer section tapers
inwardly, to have the adjacent teeth defining the intermediate
section support fastener heads of varying size. An inner slot
section follows the intermediate section and is of generally
uniform width to receive the shanks of fasteners.
[1017] The invention is also directed toward a blade for a
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lifting tool having front and rear edges, the front portion of
the blade tapered toward the front edge. The blade has slots
extending inwardly from the front edge to form outwardly
extending teeth, the slots sized to receive one size of fastener.
The blade also has slots extending inwardly from the rear edge to
form outwardly extending teeth, the slots sized to receive a
second size of fastener different from the one size of fastener
received by the teeth in the front edge.
[1018] The invention is further directed toward a blade for a
lifting tool having front and rear edges, the front portion of
the blade tapered to the front edge. The blade has slots
extending inwardly from the front edge to form forwardly
extending teeth. A strengthening ridge is formed in the blade,
the front of the ridge located between a position just
encroaching on the teeth and one half inch behind the teeth, the
ridge extending across the width of the blade and above the top
of the blade.
[1019] The invention is further directed toward a blade for a
lifting tool having front and rear edges, the front portion of
the blade tapered to the front edge. A handle socket extends
upwardly and rearwardly from about the center of the top of the
blade. A gusset is provided on the top of the blade joined both
to the top of the blade in front of the socket and to the front
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of the socket. The top of the gusset angles up from the blade to
the socket.
BRIEF DESCRIPTION OF THE FIGURES IN THE DRAWINGS
[1020] Fig. 1 is a perspective view of a lifting tool with the
blade of the present invention;
[1021] Fig. 2 is a side view of the blade;
[1022] Fig. 3 is a detail plan view showing the slots and
teeth on the front of the blade;
[1023] Fig. 4 is a side view of the blade, in partial cross-
section, catching a fastening nail;
[1024] Fig. 5 is a side view similar to Fig. 4 but with the
blade in a position after pivoting it about the bottom ridge;
[1025] Fig. 6 is a detail cross-section view showing a tapered
tooth on the blade;
[1026] Fig. 7 is a detail plan view of shaped teeth on the
blade;
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[1027] Fig. 8 is a plan view of a blade with a trapping slot;
[1028] Fig. 9 is a side view of another variation of the
blade;
[1029] Fig. 10 is a side view of a further variation of the
blade;
[1030] Fig. 11 is a side view of yet another variation of the
blade;
[1031] Fig. 12 is a partial side view of the tool, in partial
cross-section, with reinforcing features thereon; and
[1032] Fig. 12 is a side view of the tool showing the handle.
DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION
[1033] The blade 1 of the present invention, as shown in Figs.
1 and 2, is to be used with a handle 3 to provide a lifting tool
5. The blade 1 has front and rear edges 7, 9 and sides 11 joining
the edges. The blade is preferably of quadratic shape and so the
edges 7, 9 are parallel and the sides 11 are parallel and
transverse to the edges. The blade has a top surface 13 that is
preferably flat and a slightly bent bottom surface 15 that has a
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front, bottom, surface section 17 and a rear, bottom, surface
section 19. The front and rear bottom surface sections 17, 19 are
straight. The front, bottom, surface section 17 angles slightly
away from the top surface 13 as it extends rearwardly from the
front edge 7. The rear bottom surface section 19 angles slightly
away from the top surface 13 as it extends forwardly from the
rear edge 9. The front and rear bottom surface sections 17, 19
connect at about the middle of the blade along its length to form
a bottom ridge 21 which is parallel to the front and rear edges
7, 9 and extends across the blade between the sides 11. The blade
tapers in thickness moving from the ridge 21 toward both the
front and rear edges 7, 9 to provide thin edges. The ridge 21 is
shown as sharply defined, a straight line where the two straight
bottom surface sections 17, 19 meet, but the ridge can also be
slightly rounded.
[1034] The drawings exaggerate the angulation of the bottom
surface sections 17, 19 with respect to the top surface 13.
Generally, the blade might be about six inches in length between
the front and rear edges 7, 9 with the ridge 21 being about three
inches from each edge. The blade, at the edges 7, 9, would about
one sixteenth of an inch thick and about three sixteenths of an
inch thick at the ridge 21. The blade is thickest at the ridge
21. The angle ~ between the top surface 13 and the front and rear
bottom surfaces 17, 19 can range between 2° and 6°. The blade
can
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be between four and ten inches long.~The width of the blade is
normally less than it's length. Its thickness, at its thickest
point, can range between one eighth of an inch to five sixteenths
of an inch. The ridge 21 can be located anywhere within the
middle three fifths of the distance between the front and rear
edges 7, 9 of the blade. Thus, for example, for a blade ten
inches long, the ridge 21 can be located anywhere more than two
inches from each edge. The blade is normally manufactured by
machining a piece of steel plate.
[1035] The handle 3 can be a wooden handle fixedly mounted in
a socket 23, the socket welded to the top center of the blade and
angled rearwardly and upwardly about forty five degrees as shown.
Alternatively, the handle 3 can be a metal rod or tube welded
at one end to the top surface 13 of the blade 1, the handle
located generally in the center of the blade and angled
rearwardly and upwardly about forty five degrees.
[1036] The blade described can be used as is to lift and pry
up material from a support surface. The long, wedge-shaped front
portion of the blade is easily pushed and worked farther under
the edge of material on the support surface of a roof, the blade
sliding on the support surface on its front bottom surface 17.
The blade slides quite easily since it is only sliding on the
front bottom surface and not on the whole bottom surface of the
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blade. Once the front portion is well under the material, the
blade can be pivoted by the handle 3 on the ridge 21 to rest on
its rear, bottom surface 19. This has the effect of breaking away
the material away from the support surface. Once the material is
broken away, the blade can be further pivoted about its front or
rear edges 7, 9 to further lift the material clear of the support
surface and loosen it for removal.
[1037] Preferably, at least the front of the blade 1 has
fastener receiving slots 29 extending rearwardly from the front
edge 7 of the blade. The slots 29 define a set 31 of spaced-apart
forwardly extending teeth 33 as shown in detail in Fig. 3. The
sides 35 of the teeth 33 are parallel and the fronts 37 of the
teeth 33 are angled from the sides 35 to a rounded point 39. The
angled fronts 37 of the teeth 33 define a tapered, outer, slot
portion 41 for each slot 29. The tapered, outer, slot portion 41
provides an entrance and leads to an inner, uniform-width, slot
portion 43 defined by the sides 35 of the teeth 33. The inner
slot portions 43 are wide enough to receive the shank of a
standard material fastener but not wide enough to pass the head
of the fastener and are substantially longer than the outer slot
portions 41. The teeth 33 are of course tapered to increase in
thickness moving away from the front of the teeth. The angled
fronts 37 of the teeth can be beveled laterally, if desired, as
shown at 44, to make it easier for the head of the fastener to
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move up onto the teeth.
[1038] If, as the blade 1 is slid under material on a support
surface, sliding on its front bottom surface 17, and it
encounters a tightly held fastener 'N' as shown in Fig. 4, the
shank 'S' of the fastener slides into a fastener receiving slot
29 as the blade moves forward. The head 'H' of the fastener rides
up on the sides of the teeth 33 adjacent the slot. The fastener
riding up on the sides of the tapered teeth 33 may 'crack' it
loose from the support surface. However, if it does not, the
blade is levered about its bottom ridge 21 by the tool handle 3
to slightly lift the teeth 33 until the blade rests on the
support surface on its rear, bottom surface section 19 as shown
in Fig. 5. The relatively short arm from the ridge 21 to the
slots 29 on the front of the blade, compared to the length of the
handle, provides good leverage to 'crack' the tight fastener from
the tight grip of the support surface and slightly lift it. The
fastener does not move far but it is not meant to initially. Once
the fastener is 'cracked' free and initially moved, it can be
more easily pulled out by pivoting the blade about either its
front or back edges 7, 9.
[1039] If desired, the teeth can be made more tapered in
thickness front to back by angling them from front to back at a
slightly greater angle than the angle at which the front bottom
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surface is angled to the top surface. The angling can be on the
top of the teeth 33 as shown by surface 45 in Fig. 6 but it can
also be on the bottom of the teeth if desired. The angling
extends for a length no greater than the length of the teeth. The
more tapered teeth may be shorter and are thinner at their
leading edge making it easier to insert the teeth under material.
The more tapered teeth may also make it easier to 'crack' some
fasteners.
[1040] A set 46 of teeth 47 can be provided on the rear edge 9
of the blade which are the same as the set 31 of teeth 33 on the
front edge. This allows the tool to be used in either direction
to pull fasteners. Preferably, however, one set 31 of teeth are
sized to provide slots that receive one size of fasteners, such
as asphalt shingle nails, and the other set 46 of teeth can be
sized to provide slots that receive smaller size of fasteners,
such as the nails used for cedar shakes.
[1041] The blade can be provided with shaped slots between the
teeth. The shaped slots have several advantages. They make it
easier for the fasteners to enter the slots and to move to the
end of the slots. They make it easier to try to 'crack' the
fastener. They also make it easier to sharpen the teeth to
maintain their utility, particularly the leading portion of the
teeth at the mouth of the slot where most wear occurs. The shaped
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slots 51, as shown in Fig. 7, define shaped teeth 53 between the
slots. The shaped teeth 53 each have an outer, angled section 55
defined by front sides 57 leading rearwardly from a rounded front
point 59 on the tooth and diverging rearwardly from each other by
an angle ranging from between 80° and 100°. The tapered front
sides 57 of the outer section 55 normally diverge from each other
more than the front sides of a normal pointed tooth of the type
shown in Fig. 3. .
[1042] The outer, angled section 55 is followed by an
intermediate, angled section 61 defined by intermediate sides 63
extending rearwardly from the front sides 57. The intermediate
sides 63 are slightly longer than the front sides 57 and diverge
from front to back do but not as much front sides. The
intermediate sides 63 would diverge from each other by an angle
ranging from between 30° and 60°. The tooth has a inner,
straight
section 65, behind the intermediate section 61, defined by
straight, parallel, sides 67 leading, rearwardly from the
intermediate sides 63. The straight sides 67 are longer than the
intermediate sides 63.
[1043] The slot 51 between adjacent teeth 53 has a wide,
tapered, outer, slot section 71 between the front sides 53 of the
teeth, and a tapered intermediate slot section 73, following the
outer slot section 71, between the intermediate sides 63 of the
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teeth. The outer slot section 71 provides entry to the
intermediate slot section 73. The intermediate slot section 73
converges toward a narrow inner slot section 75 of uniform width
between the straight sides 67 of the teeth.
[1044] A front side 57 of the outer angled section 55 of a
tooth initially picks up the fastener head entering a slot and
moves both sideways and forwardly relative to the fastener,
gently and easily raising the head a slight distance due to the
taper in thickness of the outer section of the tooth, and
initially 'cracking' the fastener out of the wood. The fastener
head in this stage moves relatively to the tooth on only one side
of the tooth and moves about as fast sideways as forwardly thus
gently easing the fastener head up. The fastener then moves onto
the intermediate angled section, the tooth now moving relatively
faster forwardly than sideways since the intermediate sides of
the teeth are not angled as much as the outer sides. Since the
tooth has been initially cracked it is now easier to raise the
fastener in the intermediate angled section and in this section
the fastener head becomes supported between two adjacent teeth.
Continued relative movement of the fastener occurs in moving
into, and along the length of, the inner slot section, the taper
in thickness of the blade continually raising the fastener.
[1045] The inner slot in both embodiments has been described
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as having parallel sides. However, the inner slot can also have
the sides converging toward the closed end of the inner slot so
as to be able to pick up fasteners with smaller heads such as
finishing nails. In this case fasteners with larger shanks will
not travel to the closed end of the 'slot.
[1046] While the shaped slots have been described as being in
a blade that tapers in thickness to each edge from a generally
centrally located bottom ridge, the slots can also be used in a
blade that is flat and of even thickness except for being tapered
in the area of the teeth, the teeth tapering to a thin front edge
as is known.
[1047] A blade 1" can also be provided having at least one
fastener trapping slot in a side of the blade. The blade 1" can
be a blade as shown in Figs. 1 and 2., the blade tapering from a
relatively thick middle to thin front and back edges. (The teeth
in the front and rear edges are not shown). The trapping slot 87
is a slot that extends inwardly from the side 85 of the blade,
angled toward the front edge 81 of the blade. Because the blade
tapers in thickness, the trapping slot should be located as close
to the front edge 81 as possible. The sides 89, 89' of the slot
87 are parallel. The slot 87 operates to trap or catch the shank
'S' of a fastener 'N' as the side 85 of the blade is drawn
rearwardly against and past the shank 'S' as shown by the arrow
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'A'. This occurs while the front of the blade, riding on the
front bottom surface section of the blade, is under a layer of
material on a support surface. As the mouth 91 of the slot 87
passes by the shank 'S' as the blade is drawn rearwardly, the
blade moves slightly toward the shank, the shank partly entering
the mouth 91 of the slot 87. The pointed nose 93 of the blade at
the mouth 91 of the slot 87 helps catch the shank 'S' and move it
further into the slot 81 as the blade continues its rearward
movement. The blade 1" can then be rotated while flat on its
front bottom surface section to move the shank to the bottom of
the slot and to then lever the fastener out of the wood.
Preferably, the side 89' of the slot nearest the rear edge 83 can
be rounded at the mouth 91 of the slot as shown at 95 to make it
easier for the shank of a fastener to enter the slot. A trapping
slot 87 can be provided on both sides of the blade. The trapping
slots 87 can also be used in a blade that is flat; without a
bottom ridge, and of even thickness except for being tapered in
the area of the teeth, the teeth tapering to a thin front edge as
is known.
[1048] The blade described in Figs. 1 and 2 has a bottom
surface with both the front and rear sections of the surface
angled with respect to the top surface, the front and rear bottom
sections joining to form a ridge. The blade 101 can be effective
however with a rear bottom section 119 of the bottom surface 115
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that is not angled but rather parallel to the top surface 113 as
shown in Fig. 9. In this embodiment, the front edge 107 of the
blade will not be moved as much about the ridge 121, when the
blade is pivoted about the ridge, before the rear bottom section
119 abuts against the roof surface as it would be moved if the
rear bottom section were also angled. However, the movement will
sufficient to 'crack' many fasteners. In this embodiment, the
rear edge 109 remains thick, as thick as the blade is at the
ridge 121, and this blade would have no rear teeth for use in
withdrawing fasteners. In this blade, the ridge 121 can be
located within the middle three fifths of the distance between
the front and rear edges 107, 109 although it is preferable near
the middle of the blade.
[1049] In another embodiment, the~blade of Fig. 9, may be
modified to have the top rear surface section 122 of the top
surface 113 of the blade angled down to the bottom rear surface
section 119 of the bottom surface 115, as shown in Fig. 10, to
provide a thin rear edge 110 that can have teeth (not shown)
therein. In this embodiment, the bottom rear surface section 119
can be parallel to the top front surface section 124 while still
providing both front and rear tapered portions on the blade.
[1050] In yet another embodiment, the blade could be formed to
have two spaced apart ridges on the bottom surface of the blade.
23.
CA 02558934 2006-09-05
As shown in Fig. 11, the blade 201 has front and rear edges 207,
209 joined by a flat top surface 213. The bottom surface 215 has
a straight, front, bottom surface section 217 that angles
slightly away from the top surface 213 in extending rearwardly
from the front edge 207. The bottom surface also has straight,
rear, bottom surface section 219 that angles slightly away from
the top surface 213 in extending forwardly from the rear edge
209. The blade includes an intermediate bottom surface section
225 that is parallel to the top surface 213. This intermediate
bottom section 225 is normally located in middle of the blade.
The front, bottom section 217 joins to the front of the
intermediate, bottom section 225 to form a front ridge 221 on the
bottom of the blade. The rear bottom section 219 joins to the
rear of the intermediate bottom section 225 to form a rear ridge
222 on the bottom of the blade. Teeth (not shown) can be formed
on the front and rear tapered portions of the blade, Either end
of the blade can be inserted under material on a support surface
and pivoted about the ridge nearest the end to lift the material.
[1051] Any of the blades shown, and including flat blades of
uniform thickness with a tapered front edge portion, can be
strengthened by bending the blade 301 just behind the front teeth
302 to form a small ridge 304 in the blade extending across the
width of the blade as shown in Fig. 12. The ridge 304 is parallel
to the front edge 307 of the blade. The ridge 304.a1so serves to
24.
CA 02558934 2006-09-05
direct the roofing material upwardly away from the blade. The
front portion of the ridge 304, while shown just behind the teeth
302, can be located anywhere between just encroaching on the
teeth to being about a half inch behind the teeth.
[1052] Any of the blades shown, including flat blades of
uniform thickness with a short tapered front edge portion, can be
further strengthened by welding a gusset 320 between the top
surface 313 of the blade in front of a handle socket 323 and the
front portion 322 of the handle socket 323 as shown in Fig. 12.
The gusset 320 merges the top surface 313 of the blade to the
front portion 322 of the socket 323. The gusset 320 strengthens
the blade 301 and also directs roofing material away from the
blade and up the handle. The top of the gusset has been shown
straight. It can also be made slightly concave to more smoothly
merge the top of the blade to the front of the socket. While the
blade has been shown with a handle socket, the gusset could also
be used with a blade connected directly to a metal handle, the
gusset connected to both the top of the blade and the handle.
[1053] The tool has been shown in Figs. 1 and 2 with a socket
and a wooden handle extending from the socket. The tool 405, as
shown in Fig. 13, can also have a metal handle 403, the handle
welded at its front end 424 to the tQp surface 413 of the blade
401 and having a relatively short front portion 426 extending
25.
CA 02558934 2006-09-05
upwardly and rearwardly from the blade at an angle of about forty
five degrees. The handle can be tubular or solid. The handle 403
can have a slight downward bend 428 near the blade 401 to
position the grip portion 430 of the handle 403 of the tool in a
better position for the user of the tool. The grip portion 430 is
relatively long compared to the front portion 426, the grip
portion being gripped during use near its far end spaced
from the front portion 426. The grip portion 430 extends at an
angle to the blade which is substantially less than the angle at
which the front portion of the handle extends to the blade. The
grip portion 430, being lowered during use due to bend 428,
allows the user to more easily insert the tool blade under
material, while the front portion 426 of the handle, extending at
about a forty five degree angle to the blade, still allows the
user to lever the blade upwardly. The handle 403 can have a
second bend 432 just behind the grip portion 430 to angle the
rear portion 434 of the handle, just behind the grip portion 430,
downwardly. This allows the rear portion 434 of the handle to hit
the support surface first and protect the hand of the user on the
grip portion 430, just above the rear portion 434, from hitting
the support surface when maneuvering the tool to lift material
and fasteners. The tool 405 with the handle 403 is shown with a
blade as shown in Figs. 1 and 2. However, the tool can have any
kind of blade with any type of teeth and any type of blade
reinforcing means.
26.
CA 02558934 2006-09-05
[1054] The tool can also include an impact receiving member
436 on the handle 403 just above the blade 401 as shown in Fig.
13. The member 436 can comprise a cylindrical bar 438, the bar
438 welded onto the front portion 426 of the handle 403 and
extending transverse to it, the bar 438 parallel with the front
edge 407 of the blade 401. The bar 438 can be hit by the user
with a hammer to force the tool forward when needed, such as when
cutting material being removed. The impact receiving member 436
could be a square bar instead of cylindrical, or it could have
other shapes. The member 436 could also be attached to the top of
the blade 401 if desired instead of on the handle as shown. The
impact receiving member is also wide enough to allow the user to
step on it to help force the blade under into the material. The
impact receiving member could also be attached to the socket of a
tool employing a wooden handle.
27.
