Note: Descriptions are shown in the official language in which they were submitted.
CA 02545744 2006-05-03
SNOW SHOVEL
TECHNICAL FIELD
[0001 ] The present invention relates generally to snow shovels and snow
pushers and in
particular to a snow shovel/pusher having a blade and a shaft, wherein the
blade is pivotable in a
horizontal plane along a side-to-side arch with respect to the shaft and the
shaft maintains a constant
angle with respect to the blade.
BACKGROUND
[0002] The common snow shovel or pusher has been around for years and
generally
comprises a large flat or curved blade for pushing snow lying on a horizontal
working surface such as
a sidewalk or driveway. A shaft is rigidly affixed at a 90 degree angle to the
back of the blade and is
angled upward for gripping by a user standing behind the blade. One
disadvantage of this type of
snow shovel is that since the blade is fixed rigidly at a 90 degree angle to
the shaft, it is only useful
for pushing or shoveling snow in a forward direction. The problem is that snow
tends to build up in
front of the blade when being pushed forward in this manner. To push snow to
the side, the user has
to twist his or her body to the left or right, thereby straining the back and
neck muscles and risking
injury.
[0003] Another disadvantage of the common snow shovel or pusher occurs when
working
against a wall or fence. To move the snow away from a wall one must angle the
blade sufficiently
with respect to the wall so as to direct the snow away from the wall and allow
it to slide off the
shovel. However, one is impeded in this movement by contact between the shaft
of the shovel and
the wall, which prevents the attainment of a sufficient working angle for
efficient movement of the
snow away from the wall.
[0004] One solution is described in U.S. Patent No. 4,597,204, which provides
a snow
pusher having a handle pivotally attached to an angled latch plate at the back
of a blade, allowing the
angle of the handle relative to the length of the blade to be adjusted. This
allows the blade to be
positioned at an angle with respect to the shaft for pushing snow to the side.
However, the problem
with this design is that in order to keep the shovel blade flat and parallel
to the ground during use, the
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user has to lower the working angle of the shaft relative to the ground. This
puts the user in an
awkward position relative to the blade and could cause strain and injury.
[0005] A further disadvantage of the common snow shovel or pusher is that the
normal
working surface is usually made of asphalt or concrete and is often irregular,
having cracks and
raised areas. Therefore, the blade tends to wear rather quickly and/or become
damaged, necessitating
replacement of the blade or, in most cases, the entire shovel. Other
components of the common snow
shovel are likewise not replaceable, so that when a part breaks or wears out
it cannot be easily
replaced. In the past, the only solution has been to replace the entire shovel
with a new one.
SUMMARY
[0006] Accordingly, in view of the foregoing, there is a need for a snow
shovel or snow
pusher that will overcome the disadvantages of the prior art.
[0007] There is a further need for a snow shovel or pusher having a blade that
is pivotable
in a horizontal plane right and left with respect to the shaft on a central
axis perpendicular to the
working surface.
[0008] There is additionally a need for a snow shovel or pusher having a blade
that is
pivotable in a horizontal plane right and left with respect to the shaft while
at the same time
maintaining the shaft at a constant working angle relative to the working
surface to prevent strain and
injury to the user.
[0009] There is also a need for a snow shovel having a pivotable blade and a
releasable
locking mechanism operable for releasing and relocking the blade at various
angles relative to the
shaft and wherein releasing the locking mechanism is accomplished with only a
slight movement of
the user's hand or foot and does not require great effort.
[0010] There is a further need for a snow shovel having a pivotable blade as
described
above, wherein the releasable locking mechanism can be released remotely using
a trigger
mechanism within easy reach of the user.
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[0011 ] There is also a need for a snow shovel having a reversible, two-sided
blade with two
working edges, so that when one working edge wears or breaks, the blade can be
turned around or
reversed to expose or activate the second working edge.
[0012] There is a further need for a snow shovel having replaceable parts so
that when one
part breaks or wears out the worn or broken part can be easily replaced.
[0013] According to one aspect then, there is provided a snow shovel for
pushing snow on a
generally horizontal working surface, the snow shovel comprising: an elongated
shaft for gripping by
a user during use; a shovel blade having a front side and a rear side and a
horizontal bottom working
edge for engaging the working surface during use, the rear side of the shovel
blade attached to one
end of the shaft with a yoke mechanism for pivotally retaining the shovel
blade at various angles
relative to the shaft, the shovel blade being pivotable relative to the shaft
in a horizontal plane on a
vertical central blade axis perpendicular to the working surface; and a
releasable locking mechanism
operable for releasing and relocking the shovel blade at the various angles
relative to the shaft
between an extreme right and an extreme left position.
[0014] According to another aspect, there is provided a snow shovel for
pushing snow on a
generally horizontal working surface, the snow shovel comprising: an elongated
shaft for gripping by
a user during use, the shaft having a proximal end and a distal end and a
central longitudinal axis; a
yoke having a proximal end and a distal end, the proximal end of the yoke
connected to the distal end
of the shaft; a shovel blade having a front side and a rear side and an
elongated horizontal bottom
working edge for engagement with the working surface during use, the rear of
the shovel blade
pivotally connected to the distal end of the yoke for pivotable movement of
the shovel blade relative
to the shaft in a horizontal plane on a vertical central blade axis
perpendicular to the horizontal
bottom working edge; and a locking mechanism for locking the shovel blade at
various angles
relative to the shaft during use between an extreme right position and an
extreme left position, the
proximal end of the yoke being angled vertically upward relative to the
working surface to thereby
retain the shaft at a constant working angle with respect to the working
surface during use and during
the pivotal movement of the shovel blade relative to the shaft between the
extreme right and the
extreme left positions.
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[0015] In other aspects, the yoke is angled vertically upward relative to the
working surface
to thereby retain the shaft at a constant desirable working angle with respect
to the working surface
during use and during pivotal movement of the shovel blade relative to the
shaft. The shovel blade
may be symmetrically constructed about a central horizontal blade axis
parallel to the horizontal
bottom working edge and the shovel blade may also have a horizontal top
working edge oriented
opposite the horizontal bottom working edge, the shovel blade being removably
connected to the
yoke thereby permitting the shovel blade to be reversed, resulting in the
engagement of the top
horizontal working edge with the working surface during use.
[0016] In further aspects, the locking mechanism may include one or more lock
tabs for
selective engagement with one of a plurality of lock slots on the rear side of
the shovel blade.
Engagement of a lock tab with one of the plurality of lock slots will lock the
shovel blade and
prevent the pivotal movement of the shovel blade relative to the shaft. The
lock tab may be spring
biased for positive retention of the lock tab in a selected one of the
plurality of lock slots during use.
The one or more lock tabs may also include a release mechanism for temporarily
disengaging the
lock tab from the selected one of the plurality of lock slots to thereby
permit the pivotal movement of
the shovel blade relative to the shaft so as to permit repositioning of the
shovel blade relative to the
shaft. The locking mechanism may include a lever lock comprising a first end
and a second opposite
end and be pivotally connected to the yoke at a pivot point located between
the first end and the
second end, and a lock tab may be located on the first end of the lever lock
and a release arm may be
located on the second end, so that pressing downward on the release arm will
result in the
disengagement of the lock tab from the selected one of the plurality of lock
slots.
[0017] In other aspects, the locking mechanism may be a lock bar slidably
secured within
the yoke, the lock bar having one or more lock tabs. The lock bar is slidable
in the yoke between a
locked position where one or more of the lock tabs are engaged with one or
more of the blade lock
slots and an unlocked position where one or more of the lock tabs are
disengaged from the blade lock
slots, to thereby permit the pivotal movement of the shovel blade relative to
the shaft so as to permit
repositioning of the shovel blade relative to the shaft. The lock bar may
include a release bar,
connected between the lock bar and the yoke, for moving the lock bar between
the locked position
and the unlocked position. Further, a remote mechanism may be included for
remotely moving the
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release bar and the lock bar between the locked position and the unlocked
position. The remote
mechanism may be a cable connected between the release bar and a trigger
mechanism which may be
conveniently located within easy reach of the user.
[0018] In still further aspects, the snow shovel blade may have a support bar
connected
between the right and left sides of the blade, where the support is slidable
in a horizontal support bar
channel through the yoke or through the yoke and lock bar, as the shovel blade
is pivoted left and
right on a horizontal plane. The support bar may include a plurality of
support bar lock slots for
engagement with the one or more lock tabs of the locking mechanism.
[0019] In further aspects, the snow shovel may include stop means to prevent
the pivotal
movement of the shovel blade relative to the shaft beyond the extreme right
and the extreme left
positions when the releasable locking mechanism is not engaged. The shaft may
be removably
connected to the yoke and the yoke may be removably connected to the shovel
blade to permit
selective replacement of the shovel blade, the yoke and the shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The applicant's snow shovel will be further understood from the
following
description with reference to the drawings in which:
[0021 ] Figure 1 is an exploded, perspective view of one embodiment of the
applicant's
snow shovel showing the various main components thereof.
[0022] Figure 2 is a perspective rear view of the blade of the snow shovel
shown in
Figure I.
[0023] Figure 3 is a perspective front view of the blade of the snow shovel
shown in
Figure 1.
[0024] Figure 4 is a side plan view of the blade of the snow shovel shown in
Figure 1.
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[0025] Figure 5 is a top cross sectional view of the blade of the snow shovel
shown in
Figure 1, viewed along the line marked A in Figure 4.
[0026] Figure 6 is a perspective view of the handle of the snow shovel shown
in Figure 1.
[0027) Figures 7 and 8 are left and right side perspective views,
respectively, of the yoke of
the snow shovel shown in Figure 1.
[0028] Figure 9 is a perspective view of the torsion spring of the snow shovel
shown in
Figure 1.
[0029] Figure 10 is a side perspective view of the lever lock of the snow
shovel shown in
Figure 1.
[0030] Figure 11 is a side plan view of the lever lock of Figure 10.
[0031 ] Figure 12 is a side plan view of an assembled version of the
applicant's snow shovel
shown in Figure 1, with the handle portion removed.
[0032] Figures 13a, 13b, and 13c are top plan views of the applicant's snow
shovel of
Figure 1, showing the various positions of the blade as the blade is pivoted
on a horizontal plane
right (Figure 13a) and left (Figure 13c) with respect to the shaft. Figure 13b
shows the blade in the
standard, central position, oriented at a 90 degree angle with respect to the
shaft.
[0033] Figure 14 is a rear perspective, partial cut-away view of another
embodiment of the
applicant's snow shovel, showing the pivotal attachment of the yoke to the
back of the blade. The
blade shown in Figure 14 includes additional reinforcement ribs, and the shaft
has been partially cut-
away.
[0034] Figure 15 is a side perspective, partial cut-away view of a further
embodiment of the
applicant's snow shovel, showing an alternate design for the pivotal
attachment of the handle to the
blade. The shaft has been partially cut-away.
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[0035] Figure 16 is a rear side perspective, partial cut-away view of another
embodiment of
the applicant's snow shovel, showing a further alternate design for the
pivotal attachment of the
handle to the blade. The shaft has been partially cut-away.
[0036] Figure 17 is a top plan view of the snow shovel shown in Figure 15.
[0037] Figure 18 is a top plan view of the snow shovel shown in Figure 15,
including the
addition of a remote release mechanism.
[0038] Figure 19 is a side cross sectional view of the blade of the snow
shovel shown in
Figure 17, viewed along the line marked B/C in Figure 17. The lock bar is
shown in the locked,
working position.
[0039] Figure 20 is a side cross sectional view of the blade of the snow
shovel shown in
Figure 17, viewed along the line marked B/C in Figure 17. The lock bar is
shown in the unlocked
position.
[0040] Figure 21 is a side cross sectional view of the blade of the snow
shovel shown in
Figure 18, viewed along the line marked D/E in Figure 18. The lock bar and
release bar are shown in
the locked, working position.
[0041 ] Figure 22 is a side cross sectional view of the blade of the snow
shovel shown in
Figure 18, viewed along the line marked D/E in Figure 18. The lock bar and
release bar are shown in
the unlocked position.
[0042] Figure 23 is a top plan view of the snow shovel of Figure 16, from the
perspective of
a user, showing the blade rotated on a horizontal plane to the right or
clockwise with respect to the
shaft.
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DETAILED DESCRIPTION
[0043] In the following discussion, reference to a working surface is
generally to a flat
driveway or sidewalk, which will be considered as being generally on a
horizontal plane. A user
standing on the working surface is generally oriented in a vertical direction
perpendicular to the
horizontal plane of the working surface.
[0044] Figure 1 is an exploded view of the applicant's snow shovel or pusher
10, including
a blade 12 for pushing or shoveling snow on the above-mentioned generally
horizontal working
surface and an elongated shaft 14 for gripping by a user, the shaft having a
proximal end 15 and a
distal end 13 and a central longitudinal axis "A". A handle 16 may be fitted
onto the proximal end
of shaft 14 and secured using a handle fastening means 17.
[0045] The distal end 13 of shaft 14 is secured to a proximal end 21 of an
angled yoke 22
15 using a shaft fastening means 19. Yoke 22 is angled vertically upward with
respect to the working
surface, the angle of yoke 22 being calculated to provide a desirable upward
working angle with
respect to the working surface for the user gripping shaft 14 to work the snow
shovel. A releasable
locking mechanism comprising a lever lock 24 and a torsion spring 26 are
pivotally secured to yoke
22 with a pin or bolt 25 (as will be discussed in further detail below).
[0046] The blade 12 is pivotally secured to a distal end 23 of the yoke 22
using a blade
fastening means 30. As shown in Figures 1-4, 12 and 14, blade 12 has a
horizontal bottom working
edge 12a. Advantageously, blade 12 also has an oppositely-oriented horizontal
top working edge
12b and may be curved between bottom edge 12a and top edge 12b so as to
facilitate the pushing and
shoveling of snow. Blade 12 may be symmetrically shaped about a central
horizontal blade axis "C"
parallel to the top and bottom edges 12a and 12b, as shown in Figure 3. This
symmetrical shape
provides blade 12 with the same working profile regardless of whether edge 12a
is used against the
working surface, or the blade is turned over and edge 12b is used.
[0047] Blade 12 may include multiple vertical reinforcing ribs 32 and at least
two
horizontal reinforcing ribs 34 (see Figure 2). Vertical reinforcing ribs 32
intersect with horizontal
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reinforcing ribs 34, to form a central cavity 36 having an upper yoke
attachment plate 38, a lower
yoke attachment plate 39, and two side walls 40 and 41. Additional reinforcing
ribs 33, which may
be oriented other than horizontally or vertically, as shown in Figure 14, may
be added to the blade to
provide further stability.
[0048] Blade 12 is generally made from plastic, but may in the alternative be
constructed of
any suitable material, including steel or aluminum or any other suitable alloy
or a polymer composite
material. If made from plastic or a composite material, blade edges 12a and
12b may be reinforced
with a metal strip to prevent wear. The metal strip may be a V-shaped strip
secured to the blade
edges.
[0049] As shown in Figure 5, upper yoke attachment plate 38 includes an upper
pivot hole
42 for alignment with a yoke pivot hole 56 (see Figures 7 and 8) for pivotal
attachment of yoke 22 to
the rear side of blade 12. Yoke attachment plate 38 includes at least three
upper blade lock slots 44a,
44b, and 44c for alignment with a yoke lock slot 58 (see Figures 7 and 8) and
a locking tab 66 on
lever lock 24 (see Figures 10 and 11 ). As shown in Figures 1 and 2, lower
yoke attachment plate 39
has the same matching configuration of at least three lower blade lock slots
for alignment with yoke
lock slot 58 and locking tab 66 when blade 12 is turned over, and a lower
pivot hole for alignment
with yoke pivot hole 56 for pivotal attachment of yoke 22 to the rear side of
blade 12.
[0050] The reader will appreciate that the above-mentioned handle and shaft
fastening
means 17 and 19 may be any suitable fastening means such as a bolt, screw,
rivet or nail.
Advantageously, fastening means 17 and 19 should be suitable to permit the
removal and
replacement or reorientation of the secured parts. Advantageously, blade
fastening means 30 is a
pivot means, suitable to permit blade 12 to rotate or pivot in a horizontal
plane right (clockwise -
from the perspective of the user) and left (counter-clockwise) relative to the
central longitudinal axis
"A" of shaft 14 on a vertical central blade axis "B", defined by fastening
means 30. Central blade
axis "B" is perpendicular to blade edges 12a and 12b and to the working
surface and central
horizontal blade axis "C". Blade fastening means 30 may be any suitable means
such as a threaded
fastening means (bolt), a rivet or a pin. In particular, the applicant has
found it advantageous if blade
fastening means 30 is also designed to be removable so as to permit blade 12
to be flipped over to
engage the upper edge 12b with the working surface.
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[0051 ] Figure 6 shows handle 16, which may be any of various common
configurations,
providing a working grip for the user. Handle 16 may be secured to the
proximal end 15 of shaft 14
through a hole 50 using handle fastening means 17, which may be a screw, a
bolt, a rivet or a nail. In
the alternative, handle 16 could be affixed to the shaft by any suitable
means, including by glueing or
by forming the handle as an integral part of the shaft.
[0052] Figures 7 and 8 show left and right side views of yoke 22. Distal end
13 of shaft 14
is fitted into a suitable opening 52 in the proximal end 21 of yoke 22 and
secured using shaft
fastening means 19, which may be a screw, a bolt, a rivet, or a nail inserted
through shaft fastening
hole 54. Alternatively, shaft 14 could be affixed to yoke 22 by any suitable
means, including by
glueing or by forming shaft 14 as an integral part of yoke 22. As noted, yoke
22 is angled vertically
upward with respect to the working surface, so as to provide a desirable
upward working angle for
shaft 14 with respect to the working surface. An important advantage of the
applicant's snow shovel
is that this working angle remains constant regardless of the amount of
rotation of blade 12 left or
right with respect to the shaft.
[0053] The distal end 23 of yoke 22 is inserted into central cavity 36 of
blade 12, and
pivotally secured to the rear side of blade 12 using blade fastening means 30,
which is inserted
through upper pivot hole 42 in upper yoke attachment plate 38, through yoke
pivot hole 56, and
through a corresponding lower pivot hole in the lower yoke attachment plate
39. Upon pivotal
attachment to blade 12, yoke lock slot 58 will come into selective alignment
with the upper blade
lock slots 44a, 44b, and 44c on upper plate 38 as the blade 12 is pivoted to
the left, to the right, or to
the center. When blade 12 is turned around or reversed, yoke lock slot 58 will
respectively align
with the corresponding lower blade lock slots in the lower plate 39.
[0054] As shown in Figures 1, 10 and 11, lever lock 24 includes locking tab 66
at one end
and a release arm 68 at an opposite end. Lever lock 24 and torsion spring 26
are pivotally secured to
yoke 22 with pin 25 through holes 60 in yoke 22 and holes 62 in lever lock 24.
Spring 26 is retained
between a set of retaining ribs 64 on yoke 22 and a similar set of retaining
ribs (not shown) located
on the underside of release arm 68. Lever lock 24 is angled to conform to the
angle of yoke 22, and
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locking tab 66 is positioned to fit into yoke lock slot 58 when attached to
yoke 22. Spring 26 creates
a positive bias on lever lock 24, forcing lock tab 66 into yoke lock slot 58.
[0055] Pressing down on release arm 68 will raise lock tab 66 clear of yoke
lock slot 58,
permitting the distal end 23 of yoke 22 to be inserted into central cavity 36
and secured to blade 12,
as shown in Figure 14. Upper plate 38 is positioned between the top of yoke 22
and the bottom of
lever lock 24. Lock tab 66 is aligned with one of blade lock slots 44a, 44b,
and 44c and release arm
68 is let go, thereby engaging lock tab 66 with yoke lock slot 58, through
upper plate 38 and securing
blade 12 in one of three angled positions relative to shaft 14, thereby
preventing rotation of blade 12
relative to shaft 14 during use.
[0056] When it becomes desirable to rotate blade 12 in a horizontal plane left
(counter-
clockwise) or right (clockwise) relative to central longitudinal axis "A" of
shaft 14 (see Figure 1 ),
one merely presses down on release arm 68 to raise lock tab 66 clear of yoke
lock slot 58 and upper
blade lock slots 44a, 44b, and 44c on upper plate 38. Blade 12 is rotated to
the desired position,
aligning yoke lock slot 58 with another one of the upper blade lock slots 44a,
44b, and 44c, and
release arm 68 is let go to once again engage lock tab 66 with yoke lock slot
58 and prevent further
rotation of blade 12. Due to the downward bias of lock tab 66 created by
torsion spring 26, release
arm 68 need only be pressed briefly, sufficient to permit lock tab 66 to clear
upper plate 38 as blade
12 is rotated. Once lock tab 66 aligns with an adjacent upper lock slot 44a,
44b, and 44c, lock tab
66 will automatically engage with yoke lock slot 58, and blade 12 will be once
again locked into the
desired angled position, ready for work.
[0057] The applicant has shown blade 12 having three blade lock slots 44a,
44b, and 44c on
upper and lower plates 38 and 39, however, it will be appreciated that
additional blade lock slots
could be used to provide a greater selection of possible angles for
positioning blade 12 side-to-side
relative to shaft 14. The amount, and therefore the angle of rotation of blade
12 right and left relative
to shaft 14 is limited by side walls 40 and 41 of cavity 36, which act as stop
means when they come
in contact with the sides of yoke 22. Side walls 40 and 41 function to limit
the rotation of yoke 22
beyond the extreme left and right positions, and thereby provide stability to
the shovel when blade 12
is in an angled position relative to shaft 14.
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[0058] In operation, shovel 10 will normally be used in the standard
configuration shown in
Figure 13b, where lock tab 66 is engaged with upper lock slot 44b and blade 12
is positioned at a 90
degree angle relative to shaft 14. If the user desires to move snow to the
left, blade 12 can be angled
left relative to shaft 14, as shown in Figure 13c, by pressing down on release
arm 68, raising lock tab
66 clear of lock slot 44b. Blade 12 is pivoted to the left so as to align lock
tab 66 with upper lock
slot 44c. The user then lets go of release arm 68 causing lock tab 66 to
engage with upper lock slot
44c and yoke lock slot 58. To move snow to the right, the same steps are
followed, except blade 12
is pivoted to the right and lock tab 66 is engaged with upper lock slot 44a.
[0059] One advantage of the applicant's snow shovel 10 is that since lock tab
66 is
positively biased into yoke lock slot 58, pivoting of blade 12 to a different
position is easily
accomplished by a single, brief downward press on release arm 68 with the
user's hand or foot.
Once lock tab 66 has cleared one of the upper blade lock slots 44a, 44b, and
44c in which it was
engaged, and blade 12 is rotated slightly, release arm 68 can be let go and
will automatically re-
engage with the adjacent upper lock slot once re-alignment is attained.
[0060] Another advantage of the applicant's snow shovel is evident when
working against a
wall or fence. To move snow away from a wall on the user's right, the user
merely has to rotate
blade 12 to the left with respect to shaft 14. The user can continue to push
the shovel forward with
the shaft 14 directly parallel to the wall, thereby causing the snow to slide
off the blade 12 to the left
and away from the wall.
[0061 ] A further advantage of the applicant's snow shovel 10 is that the
blade 12 is
constructed symmetrically about horizontal blade axis "C", having two working
edges 12a and 12b
and identical top and bottom yoke attachment plates 38 and 39. Blade fastening
means 30 is
removable, thereby allowing blade 12 to be turned around when one of the
working edges has worn
out or becomes damaged so that the opposite working edge can be engaged with
the working surface.
Once both working edges have worn, blade 12 can be removed and replaced with a
new blade.
Advantageously, all the other parts of snow shovel 10, including yoke 22,
lever lock 24, torsion
spring 26, shaft 14 and handle 16, are removably secured as well making them
easily replaced when
worn or broken.
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[0062] Another important advantage is that when blade 12 is rotated in a
horizontal plane,
side-to-side with respect to shaft 14, on vertical central blade axis "B",
keeping edge 12a (or 12b as
the case may be) parallel to the working surface, shaft 14 is maintained at a
constant working angle
relative to the working surface, thereby reducing strain and preventing injury
to users.
[0063] Figure 15 shows a further embodiment of the applicant's snow shovel or
pusher 100,
including a blade 112 for pushing or shoveling snow on a generally horizontal
working surface, the
blade having lower and upper horizontal edges 112a, 112b, and an elongated
shaft 114, the shaft
having a proximal end (not shown) for gripping by a user, a distal end 113 and
a central longitudinal
axis "A". A handle, similar to handle 16 shown in Figure 6, may be attached to
the proximal end
(not shown) of shaft 114. The distal end 113 of shaft 114 is secured to a
shaft plate 120 at a suitable
working angle. Upper and lower shaft connecting flanges 121, 123 are welded to
the shaft plate 120
at 90 degree angles.
[0064] A pivot yoke 128 is provided having an upper pivot plate 124, a lower
pivot plate
126 and a central pivot bolt 130. Lower shaft connecting flange 123 is
pivotally connected to lower
pivot plate 126 by pivot bolt 130. Upper connecting flange 121 is fixedly
connected to upper pivot
plate 124.
[0065] Upper and lower blade connecting flanges 132, 134 are secured at 90
degree angles
to a blade plate 136 fixed to the middle of the rear of blade 112. Upper blade
connecting flange 132
is pivotally connected to the upper pivot plate 124 of yoke 128 by pivot bolt
130 and the lower blade
cormecting flange 134 is fixedly connected to lower pivot plate 126.
[0066] A series of opposing, spaced-apart lock holes 140 are provided near the
outer
perimeter of lower pivot plate 126, and at least two opposing, spaced-apart
lock holes 142 are
provided in upper pivot plate 124. Two spaced-apart lock pins 150 are fastened
together at the top
with a lock pin top plate 152. Lock pins 150 are dimensioned and spaced-apart
sufficiently so that
they can be inserted through lock holes 142 and 140 opposed across the
diameter of upper and lower
pivot plates 124, 126, for slidable movement therein. Lock pin top plate 152
is fitted with a lock pin
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grip 154, which can be used to easily raise or lower the lock pins. Lock pins
150 are further fastened
together with a lock pin lower plate 156 to assist in stabilizing the lock
pins to facilitate their
insertion into lock holes 140 in lower pivot plate 126.
[0067] When lock pins 150 are raised up and clear of lock holes 140 in lower
pivot plate
126, blade 112 and lower pivot plate 126 are free to rotate. Blade 112 rotates
in a horizontal plane,
left (counter-clockwise from the perspective of the user) or right (clockwise)
relative to central
longitudinal axis "A" of shaft 114 on a vertical central blade axis "B",
defined by pivot bolt 130.
Central blade axis "B" is perpendicular to blade edges 112a and 112b and to
the working surface.
As in the previous embodiment described above, pivot bolt 130 may be any
suitable means such as a
threaded fastening means (bolt), a rivet or a pin.
[0068] One skilled in the art will appreciate that the same function as
described above can
be accomplished if lower shaft connecting flange 123 is fixedly (rather than
pivotally) connected to
lower pivot plate 126 and upper shaft connecting flange 121 is pivotally
(rather than fixedly)
connected to upper pivot plate 124, while upper blade connecting flange 132 is
fixedly (rather than
pivotally) connected to the upper pivot plate 124 and the lower blade
connecting flange 134 is
pivotally (rather than fixedly) connected to lower pivot plate 126. In this
alternate configuration,
when lock pins 150 are raised up and clear of lock holes 140 in lower pivot
plate 126, blade 112 and
upper pivot plate 124 are free to rotate left or right with respect to shaft
114 as desired.
[0069] Shovel 110 can be used in the normal fashion for pushing snow in a
forward
direction by orienting blade 112 at a 90 degree angle relative to shaft 114 so
that shaft plate 120 is
parallel to blade edges 112a, 112b. Lock pins 150 are engaged with lock holes
140 in the lower
pivot plate 126 preventing blade 112 from rotating. When it becomes desirable
to rotate blade 112 in
a horizontal plane left (counter-clockwise) or right (clockwise) relative to
central longitudinal axis
"A" of shaft 114, one raises lock pins 150 clear of lock holes 140 in lower
pivot plate 126 and rotates
blade 112 to the desired left or right position. Once lock pins 150 are
realigned with a different pair
of opposing, space-apart lock holes 140 in lower pivot plate 126, the lock
pins 150 are inserted into
the new set of lock holes 140 and further rotation of blade 112 is prevented.
The shovel is now ready
to direct snow to the left or right as desired. Lock pins 150 may be
constructed with a spring bias
14
CA 02545744 2006-05-03
connection to the top pivot plate 124 or the pivot bolt 130 to assist in
automatically engaging lock
pins 150 with lower lock holes 140 and to maintain their position therein
during operation.
[0070] In Figure 1 S, the applicant has shown lower pivot plate 126 having
three pairs of
opposed spaced-apart lock holes 140, however, it will be appreciated that
additional pairs of
opposing lock holes 140 could be provided to offer a greater selection of
possible angles for
positioning blade 112 side-to-side relative to shaft 114.
[0071 ] Figures 16-23 show a third embodiment of the applicant's snow shovel
or pusher
310. Since many of the components of the third embodiment are identical to
components of the first
embodiment shown in Figures 1-14, some of the same reference numerals will be
used in Figures 16-
23 to show the same components.
[0072] In Figure 16, snow shovel 310 includes blade 12, elongated shaft 14 and
handle 16
fitted to proximal end 15 of shaft 14 (in Figures 16-23, the handle 16 and
proximal end 15 of shaft 14
are not shown but would be identical to those same elements shown in Figure 1
).
[0073] A distal end 13 of shaft 14 is secured to a proximal end 321 of an
angled yoke 322.
Yoke 322 is angled vertically upward with respect to the working surface,
similar to the angle of
yoke 22 shown in Figure 1. As in the first embodiment, the angle of yoke 322
is calculated to
provide a desirable upward working angle with respect to the working surface
for the user gripping
shaft 14 to work the snow shovel. An important advantage of the applicant's
snow shovel is that this
working angle remains constant regardless of the amount of rotation of blade
12 left or right with
respect to the shaft. Another important advantage that the angled yoke 322
provides, is that it limits,
to a certain extent, the amount of snow that can be carned in blade 12. The
angle of yoke 322 (and
of yoke 22 shown in Figure 1 ), combined with the curvature of blade 12,
limits the ability of a user to
tip blade 12 backwards for the purpose of loading it with an excess of snow.
The result is that the
user is not able to pickup and throw large amounts of snow. This can be an
important consideration,
particularly for elderly persons, or those with weak backs, as it prevents
them from over exerting
themselves and limits possible injury.
CA 02545744 2006-05-03
[0074] As shown in Figure 16, and more particularly in Figures 19 and 20, a
releasable
locking mechanism, comprising a "double-J-shaped" lock bar 324 is slidably
secured within a
vertical main yoke lock channel 327a and a vertical secondary yoke lock
channel 327b in yoke 322,
with a spring 326 (see Figures 19 and 20) and a spring plate 325 secured to
the bottom of yoke 322.
Lock bar 324 includes rear lock bar tab 366a and upper and lower front lock
bar tabs 366b, and 336c,
respectively. Upper and lower front lock bar tabs 366b, and 336c are
positioned to slide up and
down within secondary yoke lock channel 327b, while rear lock bar tab 366a is
positioned to slide up
and down within main yoke lock channel 327a. Spring 326 creates a positive
bias on lock bar 324,
forcing lock tabs 366a, 366b and 366c upward as shown in Figure 19. Pushing
downward on yoke
322, in direction "D" as shown in Figure 20, causes lock bar 324 to slide
downward in yoke lock
channels 327a and 327b. Once pressure is released on the top of yoke 322, lock
bar 324 will return
to its resting, locked/working position as shown in Figure 19.
[0075] One will appreciate that lock bar 324 may be "single-J-shaped" and may
have only
one of upper and lower lock tabs 366b and 366c. In both the "double-J" and
"single-J"
configurations, rear lock bar tab 366a is not essential and may be omitted.
One will also appreciate
that it would also be possible that lock bar 324 is not a "J-shaped"
configuration and that only rear
lock bar tab 366a is included. In this latter configuration, real lock bar tab
366a would be essential.
[0076] The blade 12 is pivotally secured to a distal end 323 of yoke 322 using
blade
fastening means 30. Blade 12 has the same characteristics described earlier,
including horizontal
bottom working edge 12a, oppositely-oriented horizontal top working edge 12b,
and a curved
connecting surface between edges 12a and 12b to facilitate the pushing and
shoveling of snow. As
shown in Figure 3, blade 12 may also be symmetrically shaped about a central
horizontal blade axis
"C" parallel to the top and bottom edges 12b and 12a, permitting blade 12 to
be turned over.
[0077] As previously described, blade fastening means 30 is a pivot means,
suitable to
permit blade 12 to rotate or pivot in a horizontal plane right (clockwise -
from the perspective of the
user) and left (counter-clockwise) relative to the central longitudinal axis
"A" of shaft 14 on a
vertical central blade axis "B", defined by fastening means 30. Central blade
axis "B" is
16
CA 02545744 2006-05-03
perpendicular to blade edges 12a and 12b and to the working surface and
central horizontal blade
axis "C".
[0078] Blade 12 may include multiple vertical reinforcing ribs 32 and at least
two
horizontal reinforcing ribs 34 (see Figure 2). Vertical reinforcing ribs 32
intersect with horizontal
reinforcing ribs 34, to form a central cavity 36 having an upper yoke
attachment plate 38, a lower
yoke attachment plate 39, and two side walls 40 and 41. Additional reinforcing
ribs 33, which may
be oriented other than horizontally or vertically, as shown in Figures 14 and
16, may be added to
blade 12 to provide further stability.
[0079] In the applicant's third embodiment, as shown in Figure 16, blade 12
includes
additional left and right horizontal support ribs 337, located between
horizontal support ribs 34, for
securing a curved "U-shaped" blade support bar 350 (see also Figures 17 and
18, which show top
plan views of snow shovel 310). Support ribs 337 are best located centrally on
central horizontal
blade axis "C"and positioned an equal distance on either side of fastening
means 30. Support bar
350 is fastened on both the left and right sides of blade 12 using support bar
fastening means 352 and
is on the same horizontal plane as central horizontal bade axis "C". The
angled, bottom portion of
"U-shaped" support bar 350 is inserted through a horizontal support bar
channel 354 cut through both
yoke 322 and lock bar 324 (see Figures 19 and 20) and is slidable therein as
blade 12 is rotated
horizontally left and right. One will appreciate that in the first embodiment
of the applicant's snow
shovel, as shown in Figures 1-14, a support bar (not shown), similar to
support bar 350, could also be
added to provide additional support to snow shovel 10 and blade 12. In that
alternate version of
snow shovel 10, support bar channel 354 would only be cut through yoke 22 and
support bar 354
would be slidable therein as blade 12 is rotated horizontally left and right.
[0080] Support bar 350, which when connected becomes part of blade 12, may
include at
least three additional blade or support bar lock slots 355a, 355b, and 355c
(see Figure 23) for
engagement with rear lock bar tab 366a as blade 12 pivots horizontally left
and right. Support bar
350 provides blade 12 with additional support to prevent twisting while
digging or pushing heavy
loads and support bar lock slots 355a, 355b, and 355c provide a means to
prevent blade rotation
when engaged with rear lock bar tab 366a.
17
CA 02545744 2006-05-03
[0081 ] As shown in Figure 5, upper yoke attachment plate 38 of blade 12
includes upper
pivot hole 42 for alignment with a yoke pivot hole 356 (see Figure 19) for
pivotal attachment of yoke
322 to the rear side of blade 12. Upper yoke attachment plate 38 includes at
least three upper blade
lock slots 44a, 44b, and 44c for alignment with secondary yoke lock channel
327b (see Figure 19)
and for engagement with upper front lock bar tab 366b. As shown in Figures 1
and 2 and in Figures
19 and 20, lower yoke attachment plate 39 has the same matching configuration
of at least three
lower lock slots for alignment with secondary yoke lock channel 327b, and for
engagement with
lower front lock bar tab 366c. A lower pivot hole in lower plate 39 is also
provided for alignment
with yoke pivot hole 356 and upper pivot hole 42, for pivotal attachment of
yoke 322 to the rear side
of blade 12 using fastening means 30. As shown in Figures 17-20, upper plate
38 includes a lock slot
cover plate 347 secured with attachment means 30 to prevent snow and ice
buildup in upper blade
lock slots 44a, 44b, and 44c.
[0082] In the normal, locked working position shown in Figure 19, lock bar 324
is biased
upward by spring 326 pushing against spring plate 325 so that upper front lock
bar tab 366b is
engaged with one of upper blade lock slots 44a, 44b, or 44c in upper plate 38
and lower front lock
bar tab 366c is engaged with the corresponding lower blade lock slot in lower
plate 39. Rear lock bar
tab 366a is engaged with one of the at least three support bar lock slots
355a, 355b or 355c, thereby
locking blade 12 in a selected working position and preventing horizontal
rotation left or right.
Pushing downward on lock tab 324, in direction "D" as shown in Figure 20,
causes lock bar 324 to
slide downward in yoke main and secondary lock channels 327a and 327b, causing
lock bar tabs
366a, 366b and 366c to disengage from the lock slots, thereby permitting
horizontal rotation of blade
12. Once pressure is released on the top of yoke 322, lock bar 324 is forced
upward by spring 326,
and as soon as the lock bar tabs 366a, 366b and 366c come into alignment with
a corresponding lock
slot, lock bar 324 will return to its locked, resting/working position, as
shown in Figure 19.
[0083] One advantage of the applicant's snow shovel 310 is that due to the
upward bias of
lock bar 324 created by spring 326, pivoting of blade 12 to a different angled
position is easily
accomplished by a single, brief downward press on the top of lock bar 324 with
the users hand or
foot, sufficient to permit all lock bar tabs 366a, 366b and 366c to disengage
their respective blade
18
CA 02545744 2006-05-03
and support bar lock slots. Once lock bar tabs 366a, 366b and 366c have
cleared blade and support
bar lock slots and blade 12 is rotated slightly, downward pressure on the top
of lock bar 324 can be
released. As the blade 12 is rotated further, lock bar tabs 366a, 366b and
366c will align and
automatically engage upward into adjacent blade and support bar lock slots, to
once again
automatically lock blade 12 into the desired position, ready for work.
[0084] A further variation of the applicant's snow shovel 310 is shown in
Figures 21 and 22
to provide a means for remotely disengaging lock bar tabs 366a, 366b and 366c
from blade and
support bar lock slots, thereby permitting rotation of blade 12 without having
to bend over to push
downward on the top of lock bar 324. An "L-shaped" release bar 360 is
pivotally connected at the
angle-point 362 to yoke 322. A upper first arm 363 of release bar 360 is
fastened to lock bar 324 at
point 364 and a lower second arm 365 is connected to a cable 370 at a point
366. Cable 370 may be
located within an internal channel 380 cut into shaft 14, and extends upward
to a trigger mechanism
(not shown), near the proximal end 15 of shaft 14. Release bar 360 is, secured
as described above,
within a grove cut into the back of lock bar 324 and into the back side of
lock bar channel 327a of
yoke 322.
[0085] As shown in Figure 22, pulling upward on the trigger will pull cable
370 upward in
the direction of the arrow, and move lower second arm 366 of release bar 360
upward toward the
proximal end 321 of yoke 322. Release bar 360 pivots on the angle-point 362
forcing upper first arm
363 downward, driving lock bar 324 downward in lock bar channels 327a and
327b, to thereby
disengage lock bar tabs 366a, 366b and 366c from blade and support bar lock
slots and permit
horizontal rotation of blade 12. Releasing the trigger, allows spring 326 to
return lock bar 324 to its
resting, locked/working position, as shown in Figure 21, for engagement of
lock bar tabs 366a, 366b
and 366c with blade and support bar lock slots, thereby preventing horizontal
rotation of blade 12.
[0086] Figures 17 and 18 show the applicant's snow shovel 310 in the locked,
working
position, with blade 12 perpendicular to shaft 14 and lock bar tabs 366a, 366b
and 366c engaged
with corresponding blade and support bar lock slots. In Figure 23, snow shovel
310 has been rotated
on a horizontal plane to the right (clockwise) so that blade 12 is positioned
at an angle to shaft 14 for
pushing snow to the right. In all Figures 17, 18 and 23, the bottom edge 12a
of blade 12 remains
19
CA 02545744 2006-05-03
parallel to the working surface as shovel blade 12 is pivoted relative to the
shaft in a horizontal plane
on vertical central blade axis "B".
[0087] The applicant's snow shovel as described herein may be embodied in
other specific
forms without departing from the spirit or essential characteristics thereof.
The present embodiments
are therefore to be considered as illustrative and not restrictive, the scope
of the invention being
indicated by the appended claims rather than by the foregoing description, and
all changes that come
within the meaning and range of equivalency of the claims are therefore
intended to be embraced
therein.
