Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02229783 2006-03-14
ADJUSTABLE WING PLOW
FIELD OF THE INVENTION
This invention relates to plows fitted on vehicles for moving snow and
other materials and, more particularly, to a plow for snow and other materials
for use with
pickup trucks and other vehicles having plow wings which are individually
adjustable for
both extension of the main plow and forward angling for positioning the plow
to prevent
snow or other plowed material from slipping off the ends of the plow.
BACKGROUND OF THE INVENTION
A wide variety of snow plows for pickup trucks and other utility vehicles
are available and in use. These include straight bladed plows of the type
shown in United
States Patent 3,250,026, and center-hinged, V-plows of the type shown in U.S.
4,074,448
and 4,658,519. Other straight bladed plows have been devised with one or both
ends
being slidably extendable as shown in U.S. 2,218,512; U.S. 3,807,064; and
Swedish 323,974. Yet other plows have included straight blades with pivotable,
non-
extendable ends as shown in U.S. 4,145,825 and 3,477,151. At least one plow is
shown in
EPO 140,139 having permanently forwardly angled plow ends, which forwardly
angled
plow ends include slidable extensions wherein the entire plow swings from side
to side so
as to angle the entire plow left or right.
While each of the above types of prior known plows is useful in one or
more situations, the overall flexibility for use of these plows has been
limited. For
example, for pickup truck mounted snow plows which must be transported from
one snow
clearing site to another, it is necessary that the plow be short enough to
allow transport on
public highways which have limited lane width. However, when actually engaged
in
plowing, it is very helpful to have a greater length for the plow so that
larger areas of the
parking lot or other site can be cleared of snow more quickly. Yet another
problem
encountered is when large amounts of snow must be pushed or carried with the
plow from
one area of a clearing site to another such as the side of a parking lot. Many
of the above
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mentioned plows allow snow or other material being cleared to slip off the
ends of the plow thereby
requiring additional time and work to completely clear the site.
Existing, prior known plows have, therefore, failed to provide a plow with
sufficient
flexibility to handle the varying needs encountered in plowing using pickup
trucks or other vehicles,
especially when such vehicles must be driven on public highways. Such needs
include a short
enough plow length to allow transportation on public highways, a long enough
length for fast,
efficient clearing of a job site, and the carrying or pushing of snow from one
area to another without
allowing snow or other material to slip off the plow ends. In addition, plows
should be as light in
weight as possible while sufficiently strong to withstand the various forces
imposed thereon during
plowing of snow and other materials, should allow for proper visibility during
use as well as when
moved to a non-use position on the vehicle, and should allow ease in repair or
replacement of those
parts subject to high wear during plowing use. All of these results should be
accomplished while
minimizing the size and space required for the plow in each of its
arrangements.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides a plow having adjustable wings on
its
ends which can be adjusted to varying positions to allow transport on public
highways, to provide
increased plow length for fast, efficient clearing of snow or other material
being plowed, and to
allow carrying or pushing of snow from one area to another without the snow or
other plowed
material slipping off the plow ends. The present plow may be configured in
various arrangements
to handle each of these situations while minimizing the size and space
required by the plow when in
position on the vehicle. The present plow also allows adjustment to meet these
various situations
from a remote position in the cab of the vehicle without external, hands on
adjustment.
In one form, the invention is a plow assembly for vehicles for plowing snow or
other
materials. The assembly includes a plow having first and second ends, a front
material engaging
surface and a rear surface opposite the front surface. A support is included
for attaching the plow
blade to the vehicle. An extendable plow wing is included on the first end of
the plow. The plow
wing has inner and outer ends, a front, material engaging surface, and a rear
surface opposite the
front surface. The plow wing is mounted for sliding movement along the front
surface of the plow
at the first end between a retracted position in which the outer end of the
plow wing is adjacent the
first end of the plow blade, and an extended position in which the outer wing
end is spaced
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outwardly of the first end of the plow blade with the plow wing front surface
generally aligned with
the plow front surface. The plow wing includes a hinge. The plow wing is
pivotally mounted on
the hinge for movement between the extended position and a forwardly angled
position in which the
wing front surface extends at an angle to the plow front surface. A power
source is connected to the
plow wing and is operable to move the wing between its retracted, extended and
forwardly angled
positions.
In a preferred form of the invention, the plow assembly includes a pair of
extendable
plow wings. A first wing is mounted for sliding movement along the front
surface of the plow at a
first end of the plow. The second wing is mounted for sliding movement along
the front surface of
the plow at the second plow end. Each of the plow wings is moveable between a
retracted position
and an extended position in which the wings are generally aligned with the
plow front surface. Each
wing is also pivotally mounted on a hinge for movement between the extended
position and a
forwardly angled position in which each front wing surface extends at an angle
to the plow front
surface. A power source is operable to move each of the plow wings
independently of the other
plow wing such that the plow wings are independently movable between their
respective retracted,
extended and forwardly angled positions. The plow wings form a general U-shape
with the plow
when both plow wings are in their forwardly angled positions to facilitate
pushing snow or other
material being plowed without such material slipping off the plow ends.
In other aspects of the invention, each plow wing in one embodiment may
include a
latch assembly which prevents pivotal movement of the plow wing to the
forwardly angled position
until the plow wing is in its extended position. Further, each plow wing is
preferably mounted on a
slide, the plow wing hinge and latch assembly all being mounted on and movable
with the slide.
The slide is telescopically mounted within a slide support on the rear surface
of the plow with the
plow including an opening through which the hinge extends to support the plow
wing for sliding
movement along the front surface of the plow. When in the extended and
forwardly angled
positions, the slides cover the openings through the plow to allow continued
movement of the snow
or other material being plowed along the plow front surface.
In yet other aspects of the invention, a stop is included in one embodiment on
one of
the slides and its surrounding slide support or housing and an aperture on the
other of the slide and
housing. The aperture includes opposing ends with the stop engaging one of the
ends when the
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plow wing is in the retracted position and the other of the ends when the plow
wing is in its
extended position.
Movement of the plow wings in one embodiment is preferably made by a pair of
extendable, fluid power cylinders, one end of each fluid cylinder pivotally
connected to the rear
surface of the main plow, and the other end of the fluid cylinder pivotally
connected to the hinge.
The fluid cylinder is preferably connected to the hinge at a distance from the
pivot axis of the hinge
so that movement of the plow wing to its forwardly angled position will result
after the slide reaches
its fully extended position.
In another embodiment of the invention, movement of the plow wings is made by
two pair of extendable, fluid power cylinders, one pair of fluid cylinders
being operable to move the
first plow wing and a second pair of fluid power cylinders operable to move
the second plow wing.
In this embodiment, each of the plow wings is operable independently of the
other plow wing so
that the plow wings can independently move between their respective retracted,
extended and
forwardly angled positions as determined by the plow operator. In a preferred
version of this
embodiment, a first fluid power cylinder having a first extension distance is
connected between the
rear of the main plow and the slide to which the first plow wing is hingedly
attached. A second and
shorter fluid cylinder is attached at one end to the slide and at its other
end to the hinge for the first
plow wing. Movement of the first plow wing occurs when the first cylinder is
fully extended after
which the second fluid cylinder is activated to pivot the first plow wing from
its extended position
to its forwardly angled position.
In yet another embodiment of the invention, the main plow may include a front
material engaging surface having a first section formed from metal and a
second section formed
from polymeric material such that the weight of the second section is less
than that of the first.
Preferably, the first metal section extends from a ground engaging edge to an
intermediate position
spaced above the ground engaging edge, the plow wing being mounted for sliding
movement along
the first section. The second polymeric section extends from the intermediate
position to the top of
the plow.
In yet further aspects of the invention, the plow assembly preferably is
pivotally
mounted on a support frame adapted for attachment to the front of a pickup
truck or other vehicle.
A generally vertical pivot axis allows movement of the plow and plow wings
from a centered
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position to various angled positions to the left or right, regardless of
whether one or both of the
plow wings are angled forwardly or are aligned with the plow. Also included is
a generally
horizontal pivot connection between the plow and support frame to allow
forward pivotal movement
of the plow and plow wings in unison when the plow or wings encounter an
obstacle during
plowing. Further, biasing means and a shock absorber extend between the plow
and an intermediate
support for urging the plow and plow wings to an upright, generally vertically
oriented position
about the horizontal pivot axis. In addition, in one embodiment, the fluid
power cylinders
preferably overlap with one another along the rear of the plow so as to
maintain the overall length of
the plow assembly sufficiently short for travel on public highways.
Accordingly, the present plow assembly provides numerous advantages over prior
known plows. The present plow has sufficient flexibility to handle varying
needs including being
short enough in length when not extended to allow transport on public highways
without projecting
into adjacent lanes, can be extended to a sufficient length to allow fast,
efficient clearing of snow or
other material being plowed from a large area, and yet can be configured with
either one or both the
extendable ends angled forwardly for highly efficient carrying and/or pushing
of snow from one
location in the area being plowed to another without the snow or other plowed
material slipping off
the plow ends. All of these functions are accomplished in the present plow
with a minimal size and
space due to its compact and efficient construction. The plow may be centered
for pushing or
carrying of snow, or angled to one side or the other for moving snow or other
material to the side of
the vehicle supporting the plow. One or both plow wings at the ends of the
plow may be extended
or pivoted forwardly independently or together, while the entire plow may be
centered or angled to
one side or the other with one or both of the plow wings extended or pivoted
forwardly. In either
case, the plow wings at either end of the main plow are independently
extendable and movable to a
forwardly angled position via remote control from the cab of the vehicle by
means of hydraulic fluid
cylinders mounted along the back of the plow. Either a single fluid cylinder
or a pair of fluid
cylinders may be mounted to move each plow wing. When a pair of fluid
cylinders is used for each
wing, any latch mechanism for preventing forward movement of the wing to its
forwardly angled
position is eliminated since the second fluid cylinder which pivots the plow
between extended and
forwardly angled positions operates to lock the plow wing in whatever pivotal
position it is found.
In addition, both the main plow and the extendable wings pivot forwardly on a
horizontal axis in the
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event an obstacle is encountered during plowing. Further, when the plow wings
are extended, if the
vehicle is moved in reverse and a quantity of snow or other material being
plowed engages the rear
surface of either plow wing, either a latch mechanism or a fluid cylinder
maintains the plow wing in
alignment with the plow blade and prevents movement to the forwardly angled
position until
desired. In addition, the extendable, adjustable plow of the present invention
has been designed in a
highly compact, lightweight manner allowing use on a wide variety of pickup
trucks, utility
vehicles, tractors and other vehicles as well, including bulldozers. It may be
supported at the front
of a vehicle via the preferred support frame or by means such as vertical
supports positioned behind
the plow assembly such as in a road grader. In addition, the plow assembly of
the present invention
is rugged, strong and highly durable to allow use in harsh weather or
environmental conditions over
an extended period of time.
These and other objects, advantages, purposes and features of the invention
will
become more apparent from a study of the following description taken in
conjunction with the
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a rear perspective view of the adjustable wing plow assembly of the
present
invention wherein the plow wings are retracted and the plow is centered on a
support frame;
Fig. 2 is a top plan view, with portions broken away, of the plow assembly
with
wings retracted as shown in Fig. 1;
Fig. 3 is a front elevation of the plow assembly of Figs. 1 and 2;
Fig. 4 is an end elevation of the plow assembly of Figs. 1-3;
Fig. 5 is a rear elevation of the plow assembly of Figs. 1-4 with portions
broken
away to illustrate the fluid cylinders, hinge and slide assembly for each of
the extendable plow
wings;
Fig. 6 is an end elevation of one of the extendable plow wings;
Fig. 7 is a rear elevation of the extendable plow wing of Fig. 6;
Fig. 8 is a top plan view of the extendable plow wing of Figs. 6 and 7;
Fig. 9 is a bottom plan view of the extendable plow wing of Figs. 6-8;
Fig. 10 is rear elevation of the subassembly of a slide, plow wing pivotally
mounted
thereon, latch assembly and fluid cylinder;
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Fig. 11 is a top plan view of the subassembly of Fig. 10;
Fig. 12 is an end elevation of the subassembly of Figs. 10 and 11;
Fig. 13 is a top plan view of the subassembly of Figs. 10-12 illustrating the
plow
wing angled forwardly;
Fig. 14 is an enlarged, fragmentary view of area A in Fig. 10 illustrating the
latch
assembly for one of the extendable plow wings, the latch assembly being
engaged;
Fig. 15 is an enlarged, fragmentary view similar to Fig. 14 but showing the
latch
disengaged from the plow wing hinge;
Fig. 16 is a top plan view of the plow assembly of the present invention with
the
plow wings extended and the plow angled to the left on its support frame;
Fig. 17 is a front elevation of the plow assembly of Fig. 16 with the plow
wings
extended;
Fig. 18 is a rear elevation of the plow assembly of Figs. 16 and 17;
Fig. 19 is a sectional end elevation of the slide assembly for mounting one of
the
extendable plow wings taken along plane XIX-XIX of Fig. 18;
Fig. 20 is a sectional end elevation of one of the extendable plow wings on
its slide
assembly taken along plane XX-XX of Fig. 5;
Fig. 21 is a rear perspective view of the plow assembly of the present
invention with
the plow wings extended and angled forwardly forming a generally U-shaped
plow;
Fig. 22 is a top plan view of the plow assembly in the configuration of Fig.
21 with
portions broken away;
Fig. 23 is a rear elevation of the plow assembly in the configuration of Figs.
21 and
22;
Fig. 24 is a front elevation of the plow assembly in the configuration of
Figs. 21-23;
Fig. 25 is a schematic illustration of the hydraulic system for operation of
the
adjustable plow assembly of the present invention; and
Fig. 26 is a rear elevation of a second embodiment of the adjustable wing plow
assembly of the present invention with portions broken away and showing one of
the plow wings in
retracted position, and the other plow wing extended and angled forwardly;
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Fig. 27 is a top plan view of the plow assembly of Fig. 26 with portions of
the
support frame broken away and the top wall of the slide housing removed;
Fig. 28 is an end elevation of the plow assembly shown in Figs. 26 and 27;
Fig. 29 is a front elevation of the plow assembly of Figs. 26-28 with one plow
wing
retracted and the other plow wing extended and angled forwardly;
Fig. 30 is a front elevation of the plow assembly of Figs. 26-28 with both
plow wings
shown in extended position but not angled forwardly;
Fig. 31 is a rear elevation of one of the extendable plow wings;
Fig. 32 is a top plan view of the extendable plow wing of Fig. 31;
Fig. 33 is a bottom plan view of the extendable plow wing of Fig. 31;
Fig. 34 is a rear elevation of the subassembly of a slide, a plow wing
pivotally
mounted thereon, and the pair of fluid power cylinders for operating the slide
and plow wing
subassembly;
Fig. 35 is a top plan view of the subassembly of Fig. 34;
Fig. 35A is a top plan view of the slide member of the subassembly of Figs. 34
and
35 with portions of the front wall broken away;
Fig. 35B is a side elevation of the slide member of Fig. 35A;
Fig. 36 is a rear elevation of the subassembly of Figs. 34 and 35 illustrating
the plow
wing angled forwardly;
Fig. 37 is a top plan view of the subassembly of Figs. 34 and 35 in the
position
shown in Fig. 36;
Fig. 38 is a sectional end elevation of the slide assembly for mounting one of
the
extendable plow wings as mounted in the main plow taken along plane XXXVIII-
XXXVIII of Fig.
26;
Fig. 39 is a sectional end elevation of one of the extendable plow wings on
its slide
assembly taken along plane XXXIX-XXXIX of Fig. 26; and
Fig. 40 is a schematic illustration of the hydraulic system for operation of
the second
embodiment of the adjustable wing plow assembly of Figs. 26-39.
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIRST EMBODIMENT
Referring now to the drawings in greater detail, a first preferred embodiment
10 of
the adjustable wing plow assembly of the present invention includes a
reinforced main plow 12
pivotally mounted on a support frame 14 via an intermediate support 16.
Slidably mounted at
opposite ends 18, 20 of main plow 12 are extendable plow wings 22, 24 which
are moved by fluid
power cylinders 200, 202 remotely controlled from the cab of the pickup truck
or other vehicle on
which the plow assembly 10 is mounted. Wings 22, 24 are independently slidably
movable
between retracted positions as shown in Figs. 1-5, fully extended positions as
shown in Figs. 16-18,
and forwardly angled positions in which the plow assembly has a generally U-
shaped configuration
shown in Figs. 21-24. Plow assembly 10 is primarily adapted for plowing snow
when attached to
the front of a transport vehicle such as a pickup truck, utility vehicle,
tractor, or the like via support
frame 14. However, other materials such as gravel, bark mulch, and the like
can also be moved with
the plow. In addition, plow 12 can be mounted in other ways besides support
frame 14, such as by
vertical supports secured to the rear of the plow as explained more fully
below.
As is best seen in Figs. 1, 2 and 4, support frame 14 is preferably a
triangularly
shaped, reinforced framework having a base 26, inwardly tapering sides 28, 30
leading to a forward
apex 32, and spaced pairs of rearwardly extending support flanges 34, 36 on
base 26 adapted to
allow frame 14 to be secured to a suitable hitch assembly on the front of a
pickup truck or other
vehicle for pivotal movement about a horizontal axis A extending through the
support flanges.
Laterally extending pairs of vertically spaced cylinder support flanges 38, 40
extend outwardly from
the opposite sides 28, 30 of frame 14 and the outerlnost support flanges 34,
36. A pair of
extendable, single acting, hydraulic fluid cylinders 42, 44 are pivotally
mounted, one on either side
of frame 14, between cylinder support flanges 38, 40 and pivot pins 46, 48 on
intermediate support
16. Pins 46, 48 extend between spaced upper and lower plates 47, 49 of support
16.
Intermediate support 16 is an elongated steel beam having a generally U-shaped
configuration in cross section (Fig. 4), upper and lower plates 47, 49,
forward plate 51, and pairs of
plow mounting flanges 50a, 50b and 52a, 52b welded to the ends of plates 47,
49, 51 and to plate 51
itself and projecting forwardly toward the rear surface of plow 12. Plow 12
includes rearwardly
extending, vertically oriented supports or mounting flanges 54, 56 extending
between flanges 50a,
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50b and 52a, 52b, respectively, for mounting on horizontal rods 58, 60 aligned
on a common
horizontal axis B (Fig. 2) to allow the entire plow 12 to pivot about that
horizontal axis.
Intermediate support 16 is, in turn, pivotally mounted to apex 32 of support
frame 14 by a generally
vertically extending pivot pin 62. By controlling the extension and retraction
of fluid cylinders 42,
44, intermediate support 16 and plow 12, which is mounted thereon, may be
moved to a series of
angled positions such that plow 12 is swung and angled to the left or right
about pivot 62 as shown
in Fig. 16. Plow 12 is biased to an upright position about horizontal axis B
on pins 58, 60 by a
series of biasing members such as coil springs 64 which extend between
mounting flanges 66
extending upwardly from the top surface of intermediate support 16 and support
flanges 68 at the
top of rear surface 84 of plow 12. In addition, a shock absorber 70 is
pivotally mounted between
upstanding support flanges 72 on intermediate support 16 and rearwardly
extending support flanges
74 on the rear surface 84 of plow 12. Shock absorber 70 dampens the pivotal
movement of plow
assembly 10 about horizontal axis B on pins 58, 60 during plowing when the
plow encounters an
obstacle along the surface being plowed thereby causing the plow 12 with wings
22, 24 to tip or
pivot forwardly against the bias of springs 64. Rearward pivoting of the plow
about axis B on pins
58, 60 is limited by the rear, vertical edges of flanges 54, 56 which engage
the forward plate 51 on
intermediate support 16 (Fig. 4). Forward pivotal movement is limited by
springs 64 and shock
absorber 70. When support frame 14 is pivotally secured to a horizontal axis A
on a vehicle via
support flanges 34, 36, the entire support frame 14, intermediate support 16
and plow 12 including
extendable wings 22, 24 may be lifted away from the ground or other support
surface via a
retractable hydraulic cylinder 76 as shown in Fig. 1. Cylinder 76 is
preferably pivotally mounted
between the support frame 14 and a mounting point on the pickup truck or other
vehicle spaced
above the horizontal axis on which support frame 14 is secured.
As will be best seen in Figs. 1-3, 5, 19 and 20, main plow 12 is preferably an
elongated, rectilinear steel moldboard 80 having a concave front surface 82, a
convex rear surface
84 and an integral reinforcing flange 86 extending along its upper edge.
Secured to a lower flange
which extends along the lower edge of moldboard 80 is a reinforcing plate 88
with a replaceable
elongated, rectilinear plow blade 90 secured thereto by fasteners 92 having
countersunk heads
which are flush with the front surface of blade 90 to prevent interference
with the material being
plowed. Alternately, carriage bolts having rounded heads could be used as
fasteners 92. The upper
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portions of the right and left ends of moldboard 80 are curved to extend
outwardly on a large
radius curve (Fig. 5) so as to cover the gap between the inner edge of wing
extensions 22, 24
and the outer edges of moldboard 80 when plow extensions 22, 24 are extended
outwardly as
shown, for example, in Figs. 16-18. The rear surface 84 of moldboard 80 is
reinforced with
vertically extending supports or mounting flanges 54, 56 on either side of its
center, as well as
end flanges 94, 96 welded to rear surface 84 adjacent either end.
Extending parallel to the top and bottom edges of moldboard 80 at either end
are
elongated, rectangular slots 98, 98' best seen in Figs. 3, 17 and 19. On the
rear surface 84 of
moldboard 80 is welded a rectangular, steel slide support or housing 100
having a top wall
102, bottom wall 104, and rear wall 106 forming a generally U-shaped enclosure
which is
larger than slots or openings 98, 98' on the front of the moldboard. As will
be explained
below, slide support or housing 100 is adapted to receive a generally
rectangular inner slide
member 170, 170' best seen in Figs. 10-13 and 16-18. Synthetic, elongated wear
pad strips
108 are secured to the inner surfaces of housing walls 102, 104 and 106 to
slidably support
the slide members inside housing 100 and to maintain the slide members in
contact with the
rear surface of 84 of moldboard 80 adjacent slots 98, 98'. Preferably, wear
pads 108 are
formed from ultra high molecular weight (UHMW) plastic, although other
materials such as
Teflon*, steel and/or other materials could also be used. Mounting flanges 54,
56 and
reinforcing flanges 94, 96 extend over top wall 102, along rear wall 106 and
thereafter along
bottom wall 104 of housing 100 and are welded thereto to reinforce the entire
assembly.
When slide members 170, 170' are received within housing 100 (Fig. 19), their
front walls
178, 178' having a radius of curvature parallel to that of moldboard 80, close
slots 98, 98' on
either end of main plow 12 such that snow or other material being plowed
moving upwardly
along moldboard 80 from plow blade 90 continues along front surface 82 of the
moldboard
without interruption and without packing into the interior of housing 100.
As is best seen in Figs. 3, 5-9 and 20, each plow wing extension 22, 24 is a
substantial
mirror image of the other, only one being described in detail herein, namely,
plow wing 22.
Substantially the same elements are included in plow wing extension 24 but are
shown with
prime numerals.
Plow wing extension 22 includes a moldboard section 120 having a radius of
curvature
substantially the same as that for moldboard 80 and extending parallel to
moldboard 80
* trade-mark
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when mounted on the plow assembly. Wing extension 22 includes an integral,
upper flange 122
extending along the front surface of flange 86 at the top of moldboard 80 and
extends over slot or
opening 98 on the front surface 82 at the end of moldboard 80. A steel
extension blade 124, also
known as a cutting edge or wear edge, is secured to the front surface of the
lower edge of moldboard
120 and extends generally parallel to plow blade 90, as shown in Fig. 20.
Blade 124 engages the
plowed surface during plowing and may be repaired or replaced when worn. A
generally vertical
reinforcing flange 126 extends along the outermost edge 128 of wing extension
moldboard 120.
The innermost edge 130 of moldboard 120 is inclined downwardly and outwardly
from the position
of upper flange 122.
Extending parallel to the upper and lower edges of wing extension 22 on the
rear
surface thereof is a tapered, perforated housing 132 having a series of weight
reducing, generally
rectangular openings 134 formed therethrough, best seen in Fig. 7. Housing 132
is preferably
formed from sheet steel bent into a generally U-shaped configuration and
welded to the rear surface
of moldboard 120. Housing 132 is slightly smaller than both outer housing 100
and inner slide
member 170, as will be understood from Fig. 10. At the inner edge of wing
extension 22, within
housing 132 are a series of three spaced, generally horizontal hinge plates
136, 138, 140 which are
best seen in Figs. 7-9. These hinge plates are welded between the rear surface
of moldboard 120
and the interior of housing 132 and project inwardly a predetermined distance.
Hinge plate 136 is
shorter than plates 138, 140. As will be seen in Figs. 7-9, a vertical hinge
pivot axis X is provided
by aligned apertures 142 extending through the three hinge plates, while a
fluid cylinder pivot axis
Y is provided by apertures 144 extending through longer hinge plates 138, 140.
Hinge pivot axis X
is offset from fluid cylinder pivot Y by a predetermined distance, as shown in
Figs. 7-9 and 11, to
provide a moment arm providing torque for pivoting the wing extension on its
hinge axis, as will be
explained more fully below. Also mounted within housing 132 is a hollow,
rectangular cross
section beam 146 which extends along the lower rear surface of moldboard 120
in opposition to the
upper edge of extension blade 124. Countersunk, threaded fasteners 148 are
passed through the
front surface of extension blade 124 and beam 146 to both reinforce the lower
edge of the extension
moldboard and secure the wing extension blade 124 to the front surface of the
moldboard. A pair of
generally vertical reinforcing plates 150, 152 are welded within housing 132
at spaced positions,
reinforcing plate 152 being adjacent the inner edges of horizontal hinge
plates 136, 138, 140, as is
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best seen in Fig. 7. A diagonal reinforcement or gusset 154 extends between
plate 152 and the top
surface of beam 146 in each wing extension for additional strength. As will be
understood from
Fig. 5, plow wing extension 24 is a substantial mirror image of wing extension
22 except that
uppermost hinge plate 136' is longer than hinge plate 136. Intermediate hinge
plate 138' is spaced
more closely to upper plate 136' to allow fastening of the extension rod 203
from a fluid power
cylinder 202 which is offset from the position of the fluid power cylinder 200
engaging hinge plates
138, 140 on wing extension 22. In addition, diagonal reinforcing gusset 154'
transfers stress from
the upper fluid power cylinder 202 to the reinforcing beam 146' in wing
extension 24.
With reference to Figs. 10-15 and 19, each plow wing extension 22, 24 is
pivotally
mounted to the end of a generally rectangular slide member 170, 170', only one
of which is
described in detail herein. The subassemblies 160, 160' of slide member 170
and wing extension
22, or slide member 170' and wing extension 24 (Figs. 10-13 and 18), are both
adapted to be
slidably mounted telescopingly within housing 100 on the rear surface of main
plow moldboard 80
to allow extension, retraction and forward angling of the plow wing extensions
22, 24 by fluid
power cylinders 200, 202 as referenced above and as explained more fully
below.
Each slide member 170, 170' is an elongated beam having a generally
rectangular
cross section, formed from welded steel, and including a top wall 172, rear
wall 174, bottom wall
176, and concave front wall 178. The cross-sectional shape generally
corresponds to the cross-
sectional shape of housing 100. The radius of curvature of front wall 178 is
substantially the same
as for moldboard 80 such that front wall 178 closes slot 98 or 98' when the
plow wing extensions
are in their extended positions or angled forwardly. Rear walls 174, 174'
include elongated, closed
slots 180, 180', each adapted to receive a projecting, cylindrical stop 240,
242 which limit the
extension and retraction of the slide members, and thus, wing extensions 22,
24, as explained below.
The right-hand most fluid power cylinder 200 extends through the interior
space within slide
member 170, as shown in Figs. 5, 10, 11, 13 and 19. Fluid cylinder 202 extends
through the interior
space in slide member 170'.
Plow wing extensions 22, 24 are pivotally mounted to the outer ends of
elongated
slide members 170, 170', respectively, by hinge plates 136, 138, 140. As shown
in Figs. 10 and 11,
a hinge pin 182 is welded between top and bottom walls 172, 176 of slide
member 170 to extend
generally vertically and parallel to the outer end 184 of slide member 170.
Hinge pin 182 extends
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CA 02229783 1998-03-18
vertically through aligned apertures 142 in the hinge plates such that wing
extension 22 pivots on
axis X from a position in which moldboard 120 is generally rectilinearly
aligned with concave front
wall 178 of slide member 170 (Figs. 10 and 11) to a forwardly angled position
in which moldboard
120 extends at an obtuse angle to the front wall 178 of slide member 170 (Fig.
13). Similarly, a
shorter hinge pin 186 extends vertically through hinge plates 138, 140 and
apertures 144 on axis Y
to pivotally secure the outer end of extendable rod 201 from fluid cylinder
200. Because of the
offset between the pivot axes X and Y provided by hinge pins 182, 186, when
fluid cylinder rod 201
is extended from cylinder 200, the moment arm of the offset created by longer
hinge plates 138, 140
rotates wing extension 22 forwardly about hinge pin 182 when slide member 170
reaches its full
extension and can no longer be pushed outwardly by the extension of fluid
cylinder rod 201.
Likewise, wing extension 24 is rotated by rod 203 from cylinder 202 when slide
member 170'
reaches its fully extended position.
As shown in Figs. 5, 12-15 and 18, the pivoting of wing extensions 22, 24 from
their
extended, rectilinear positions to their forwardly angled positions is
prevented until slide members
170, 170' are fully extended by means of latch assemblies 210, 210'. In latch
assembly 210 the
lower most hinge plate 140 includes a rectangular notch or recess 212 on its
rear most edge (Figs.
13 and 15). A latch member 214 including an upwardly extending keeper 216 is
pivotally mounted
on pin 218 between the inside of rear wall 174 of slide member 170 and an
upstanding support 218a
on the inside of bottom wall 176 (Fig. 12) for pivotal movement in a generally
vertical plane. An
opening 219 extends through bottom wall 176 of slide 170 while an opening 220
extends through
the bottom wall 104 of outer housing 100 at the outer end of housing 100
adjacent outer end 18 of
the main plow moldboard. A similar pivotal latch member 214' is mounted in
slide member 170'
and similar openings extend through slide member 170' and outer housing 100
adjacent outer end 20
of plow 12. Hence, as slide members 170, 170' are slidably extended and
retracted, keepers 214,
214' travel with the slide members. When pivoted upwardly as shown in Fig. 14,
keeper 216 on
latch member 214 engages notch 212 to prevent rotation of the hinge plates
about pin 182 and, thus,
prevent forward angling movement of the wing extension to the position shown
in Fig. 13 unless the
slide member is fully extended. In its fully extended position, the latch
member 214 and opening
219 are aligned with opening 220 in the outer housing bottom wall allowing
latch member 214 to
pivot downwardly moving keeper 216 out of engagement with notch 212 and
allowing pivotal
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movement of the hinge plates. Such downward pivotal movement of the latch
member normally
occurs due to gravity when slide member 170 reaches its outermost position.
However, because
plow assembly 10 is designed for use in extreme weather conditions, which,
over time, could cause
corrosion or other restriction in pivotal movement of latch member 214 about
pin 218, a wedge
member 222 is welded to the inside surface of rear wall 106 of outer housing
100. Wedge member
222 has an inclined face 224 (Figs. 14 and 15). A pin or projection 226
extends rearwardly from
latch member 214 through a recess or opening in rear wall 174 and is engaged
by the inclined
surface 224 of wedge member 222 to force the latch member 214 to pivot
downwardly as the slide
member reaches its outermost position. Simultaneously, latch member 214 and
opening 219 come
into alignment with opening 220 in bottom wall 104 allowing the latch member
to pivot
downwardly in the intended manner. Likewise, when slide member 170 is
withdrawn or retracted
by movement to the left as shown in Figs. 10-15, pin 226 is moved out of
engagement with wedge
member 222 while the edge of opening 220 engages the downwardly inclined edge
228 of latch
member 214 to cause upward pivotal movement of the latch member. This causes
keeper 216 to re-
engage with notch 212 to lock wing extension 22 in its aligned position with
the front wall 178 of
slide member 170 and moldboard 120 in alignment with the main plow moldboard
80. Latch
assembly 210' operates in the same manner as latch assembly 210 to prevent
pivoting of wing
extension 24 until slide 170' is fully extended.
With reference to Figs. 2 and 5, it will now be understood that the
subassemblies
160, 160' of slide members 170, 170' and their pivotally attached plow wing
extensions 22, 24,
respectively, are telescopingly mounted within the interior of outer housing
100 on wear pads 108
for sliding rectilinear movement within the outer housing along a common axis.
Movement of each
slide member 170, 170' is accomplished by a power source, preferably a pair of
independent,
overlapping, double acting, hydraulic fluid cylinders 200, 202 as noted above.
Two pairs of
vertically aligned and spaced fluid cylinder support plates 230, 232 are
welded to extend rearwardly
from the rear surface 84 of main plow moldboard 80 (Figs. 2 and 5). The
nonextendable end of
fluid cylinder 200 is pivotally mounted between the lower pair of support
plates 232 on pivot pin
234. The nonextendable inner end of fluid cylinder 202 is pivotally supported
between plates 230
on pivot pin 236 (Fig. 18). Extendable rods 201, 203 from each fluid cylinder
200, 202 are
pivotally mounted between hinge plates 138, 140 and 136', 138', respectively.
Although two,
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double acting, hydraulic fluid cylinders are preferably shown for use in the
preferred embodiment of
the invention, it is within the scope of the invention to utilize other power
sources such as a single,
double acting, hydraulic fluid cylinder having extendable rods projecting from
either end.
Alternately, threaded rods rotated by at least one electric motor or a pulley
and cable system could
be used to move slides 170, 170' outwardly or inwardly for extension and
retraction.
Sliding movement of slide member 170, 170' is limited by projecting,
cylindrical
stop members 240, 242 which are mounted in the rear wall 106 of outer housing
100 (Figs. 1 and
18) in alignment with slots 180, 180' in the slide members. As fluid cylinders
200, 202 are operated
to extend rods 201, 203, slide member 170, 170' are moved rectilinearly
outwardly on wear pads
108 until stops 240, 242 engage the inner ends of slots 180, 180' stopping
further outward extension
of the plow wings. In the extended positions, as shown in Figs. 16-18, the
outer wing ends 128,
128' are spaced outwardly of the outer ends 18, 20 of main plow moldboard 80.
Since the upper
ends of the main plow moldboard 80 taper outwardly, the gap between the edges
130, 130' of the
wing extensions and the outer edges of the main plow moldboard are
substantially closed when the
wings are fully extended as shown in Figs. 16-18.
At the point of full extension, latch members 214, 214' are aligned with
openings
220, 220' in the bottom wall 104 of outer housing 100 as shown in Figs. 14, 15
and 18. In addition,
wedge member 222 on the inner surface of outer housing rear wall 106 engages
pin 226 to force
latch member 214 to pivot downwardly releasing keeper 216 from notch 212 in
hinge plate 140.
The same occurs with latch assembly 210' such that wing extension 24 is
released. Thus, at the
fully extended position, plow wing extensions 22, 24 are unlocked, released
and freed to pivot
forwardly from their extended positions in which the moldboards 120, 120' are
substantially parallel
to the front surface 82 of moldboard 80 and in rectilinear alignment
therewith. Further extension of
pivotally mounted fluid cylinders 200, 202 causes rotation of wing extensions
22, 24 forwardly
about hinge pins 182, 182' due to the distance between pivot axes X and Y as
shown in Fig. 7 and
because further outward extension of slide member 170, 170' is prevented by
stop members 240,
242 engaging the ends of slots 180, 180'. Such cylinder extension causes
rotation of the plow wings
to the positions shown in Figs. 21-24 such that both wing extensions are
pivoted forwardly at an
obtuse angle to the main plow moldboard and thereby forming a generally U-
shaped configuration
for the plow assembly. In such position, as shown in Figs. 22-24, ends 18, 20
of main plow
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CA 02229783 1998-03-18
moldboard 80 substantially overlap the inner edges 130, 130' of the wing
extensions. The outward
taper of edges 130, 130' allows the extensions to be pivoted to the forward
position without
interference between those edges and the main plow moldboard. Hydraulic
pressure within
cylinders 200, 202 keeps the wing extensions in the forwardly pivoted
positions for pushing or
carrying snow such that the snow does not slip off the ends of the plow
assembly. At the same time,
front walls 178, 178' of slide member 170, 170' cover the openings 98, 98' in
the main plow
moldboard and prevent snow from being packed into the inside of the outer
housing and allow the
plow assembly to function normally.
Likewise, when fluid cylinders 200, 202 are retracted, the opposite motions
occur.
First, wing extensions 22, 24 are pivoted rearwardly into alignment with main
plow moldboard 80
about pivot pins 182. When housings 132, 132' are aligned with slide members
170, 170' further
retraction of the fluid cylinders causes latch members 214, 214' to pivot
upwardly and engage
notches 212, 212' as the slide members are retracted. Further retraction of
the fluid cylinders causes
the plow wings 22, 24 to move along the front surface of the main plow
moldboard to the retracted
positions shown in Figs. 1-3 and 5. Inward movement of the slide members 170,
170' is limited by
the stop members 240, 242 engaging the outer ends of slots 180, 180'
preventing further inward
sliding movement of the slide members. In each position, openings 98, 98'
allow the hinged wing
extension to be mounted on slides 170, 170' adjacent the rear surface 84 of
main plow moldboard 80
with the hinges extending through the openings for movement of wing extensions
22, 24 along the
front surface of the main plow. Thus, the plow assembly may be used in its
retracted position to
plow snow when either centered or angled to the left or right, the preferred
length of such plow in
the retracted position being approximately 8 feet. Secondly, cylinders 200,
202 can be extended
simultaneously or independently of one another such that wing extensions 22,
24 are in their fully
extended positions as shown in Figs. 16-18 and the plow may also be used
either centered or angled
left or right by extending one or the other of fluid cylinders 42, 44. With
the wing extensions fully
extended, the plow assembly has an overall length of approximately eleven
feet. Further, as shown
in Figs. 21-24, yet further extension of cylinder 200, 202 causes forward
pivotal movement of plow
extensions 22, 24 to the positions shown therein providing a substantial U-
shape for the plow
assembly allowing snow or other material to be pushed or carried from one
position along a
horizontal surface to another without the snow slipping off the ends of the
plow assembly. It is also
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CA 02229783 1998-03-18
possible to extend only one or the other of wing extensions 22, 24 such that
the plow may be used
with only one end extended or pivoted forwardly, or one end extended with the
opposite end
extended and pivoted forwardly.
As shown in Fig. 25, each hydraulic fluid cylinder 200, 202 is controlled by a
pair of
solenoid operated valves 250, 252 and 250', 252' which direct hydraulic fluid
from the hydraulic
system into the fluid cylinder to either extend or retract rods 201, 203.
Pressure release valves 254,
254' are included within the system to prevent over pressurization of each of
cylinders 200, 202.
Likewise, angling of the plow assembly to the left or right is accomplished by
fluid cylinders 42, 44
which are controlled by solenoid operated fluid valves 256, 258, respectively.
Again, pressure
release valves 260, 262 are included between the hydraulic lines leading to
cylinders 42, 44 to
prevent over pressurization. Pressure release valves 254, 254' release
pressure exerted on the
system should wings 22,24 encounter an obstacle or other sudden rearward load
when extended and
pivoted forwardly and allow hydraulic fluid to be directed back to storage to
provide system relief
when forces generated exceed specified system pressures. Likewise, valves
260,262 release
overload pressures exerted on angling cylinders 42,44 in the event an obstacle
engages the plow.
In the event a lift cylinder 76 is included on support frame 14, it too may be
operated
by a solenoid operated fluid valve 264 with a hydraulic lock valve 266
included in the system to
hold the lift cylinder 76 in position when raised. All of these fluid
cylinders can be easily controlled
with the solenoid operated fluid valves 250, 252, 250', 252', 256, 258, 264,
and 266 having electrical
controls which are positioned on a control panel in the cab of the vehicle for
easy access by the
driver to allow operation without leaving the vehicle cab. Such remote control
greatly increases the
speed and efficiency of adjustment of the plow assembly without the need for
exiting the cab.
SECOND EMBODIMENT
Referring now to Figs. 26-40, a second preferred embodiment 300 of the
adjustable
wing plow assembly of the present invention is illustrated including a
reinforced main plow 312
pivotally mounted on a support frame 314 via intermediate support 316.
Slidably mounted at
opposite ends 318, 320 of main plow 312 are extendable plow wings 322, 324
each of which are
moved by pair of fluid power cylinders 500a, 502a or 500b, 502b remotely
controlled from the cab
of the pickup truck or other vehicle on which the plow assembly 300 is
mounted. Wings 322, 324
are independently slidably movable between retracted positions as shown in
Figs. 26-29, fully
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CA 02229783 1998-03-18
extended positions as shown in Fig. 30, and forwardly angled positions in
which the plow assembly
has a generally U-shaped configuration as shown in Figs. 26-29, 36 and 37.
Figs. 26-29 are shown
with one wing extended and angled forwardly, and one wing fully retracted
which is another
optional position in which the plow may be used. In addition to the use of a
pair of fluid power
cylinders for movement of each of the plow wings, embodiment 300 of the
adjustable wing plow
also incorporates a modified main plow construction in which an upper section
of the main plow
moldboard 380 is preferably formed from a sheet polymeric material such as
opaque UHMW
polyethylene or clear polycarbonate. Such material lessens the overall weight
of the plow assembly
and also provides additional visibility through the clear material at the top
of the plow moldboard
especially when the plow assembly is mounted on a vehicle and lifted to an
inoperative position. In
addition, the construction of the plow wings and main plow is modified for
ease and strength of
attachment of the extension blade 424 of the main plow moldboard and
rectilinear plow blade 390
secured to the lower edge of each plow wing 322, 324. In addition, support
skids 410 are mounted
at either end of the rear of the main plow assembly.
As is best seen in Fig. 27, support frame 314 is preferably a triangularly
shaped,
reinforced framework substantially similar to support frame 14 including
inwardly tapering sides
328, 330 leading to a forward apex 332. Not shown in Fig. 27 are a series of
support flanges at the
rear of support frame 314 to allow frame 314 to be secured to a suitable hitch
assembly on the front
of a pickup truck or other vehicle for pivotal movement about a horizontal
axis extending through
such support flanges. A pair of extendable, single-acting, hydraulic fluid
cylinders 342, 344 are
pivotally mounted one at either side of frame 314 in a manner similar to that
shown for support
frame 14 between the support frame and pivot pins 346, 348 on intermediate
support 316. Pins 346,
348 extend between spaced upper and lower plates 347, 349 of support 316.
Intermediate support 316 is an elongated steel beam having a generally U-
shaped
configuration in cross section and substantially similar to support 16
described above in connection
with embodiment 10. Included are upper and lower support plates 347, 349, a
forward plate 351,
and two pair of plow mounting flanges 350a, 350b and 352a, 352b welded to the
ends of plates 347,
349, 351 and to plate 351 itself and projecting forwardly toward the rear
surface of plow 312. Plow
312 includes rearwardly extending, vertically oriented supports or mounting
flanges 354, 356
extending between flanges 350a, 350b and 352a, 352b, respectively, for
mounting on horizontal
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CA 02229783 1998-03-18
rods 358, 360 aligned on a common horizontal axis B (Fig. 27) to allow the
entire plow 312 to pivot
about that horizontal axis. Intermediate support 316 is, in turn, pivotally
mounted to apex 332 of
support frame 314 by a generally vertically extending pivot pin 362. By
controlling the extension
and retraction of fluid cylinders 342, 344, intermediate support 316 and plow
312, which is mounted
thereon, may be moved to a series of angled positions such that plow 312 is
swung and angled to the
left or right about pivot pin 362 just as in the case of embodiment 10
described above.
Plow 312 is biased to an upright position about horizontal axis B on pins 358,
360 by
a series of biasing members such as coil springs 364 which extend between
mounting flanges 366
extending upwardly from the top surface of intermediate support 316 and
support flanges 368 at the
top of rear surface 384 of plow 312. In addition, a shock absorber 370 is
pivotally mounted
between upstanding support flanges 372 on intermediate support 316 and
rearwardly extending
support flanges 374 on the rear surface 384 of plow 312. Like shock absorber
70, shock absorber
370 dampens the pivotal movement of plow assembly 300 about horizontal axis B
on pins 358, 360
during plowing when the plow encounters an obstacle along the surface being
plowed being thereby
causing plow 312 with wings 322, 324 to tip or pivot forwardly against the
bias of springs 64.
Rearward pivoting of the plow about axis B on pins 358, 360 is limited by
contact of flanges 354,
356 with intermediate support 316. Forward pivotal movement is limited by
springs 364 and shock
absorber 370. When support frame 314 is pivotally secured to a horizontal axis
on a vehicle, the
entire support frame 314, intermediate support 316 and plow 312 including
extendable wings 322,
324 may be lifted away from the ground or other support surface via a
retractable hydraulic cylinder
376 or other power source (Fig. 40) in the manner described above in
connection with embodiment
10.
As will be best seen in Figs. 26-30, 38 and 39, main plow 312 is preferably an
elongated, rectilinear moldboard 380 having a concave front surface 382, a
convex rear surface 384,
and an integral steel reinforcing flange 386 extending along its upper edge.
Secured to a lower
flange which extends along a lower edge of moldboard 380 is a reinforcing
plate 388 with a
replaceable, elongated, rectilinear plow blade 390 secured thereto by
fasteners 392 having
countersunk heads which are flush with the front surface of blade 390 to
prevent interference with
the material being plowed. As in embodiment 10, carriage bolts having rounded
heads could also
be used in place of countersunk fasteners 392. Carriage bolts 392 are
elongated for additional
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CA 02229783 1998-03-18
strength and extend through spaced, cylindrical mounts 393 welded to the rear
surface of plate 388
(Figs. 26, 38, 39). The upper portions of the right and left ends of moldboard
380 are curved to
extend outwardly on a large radius curve (Fig. 26) so as to cover the gap
between the inner edge of
wing extensions 322, 324 and the outer edges of moldboard 380 when plow
extensions 322, 324 are
extended outwardly and forwardly as shown, for example, in Figs. 26-29. The
rear surface 384 of
moldboard 380 is reinforced with vertically extending supports or mounting
flanges 354, 356 on
either side of its center, as well as end flanges 394, 396 welded to flange
386 and plate 388 adjacent
either end.
As is best shown in Figs. 29, 38 and 39, rectilinear moldboard 380 is
preferably
formed in two sections, a first, steel section 383 which extends from the top
of plow blade 390 to a
position approximately two-thirds up the overall height of the moldboard. A
second, upper, curved
section of the moldboard 385 is preferably formed from a polymeric sheet
material such as opaque
UHMW polyethylene or clear polycarbonate which is preferably bolted to
mounting flanges 354,
356 and end flanges 394, 396 with its free lower edge 387 fitted in a pocket
formed by the upper
edge of moldboard section 383 and a horizontally extending reinforcing flange
389 secured on the
rear surface of the main plow. Accordingly, when material to be plowed, such
as snow, engages the
plow blade 390 it is forced upwardly along first moldboard section 383 which
bears the principal
amount of force causing the material to change directions, while the remainder
of first section 383
and second section 385 impart a rolling action or a continuation of the change
in direction to force
the snow forwardly as the plow is moved in the same direction. The preferred
polymeric sheet
material 385 saves a significant amount of weight in the overall plow
assembly, namely,
approximately 30 pounds in an eight foot plow assembly, and also provides the
ability to view
through the upper section of the plow, especially when the plow assembly is
raised to its inoperative
position when mounted on a truck.
Extending parallel to the top and bottom edges of moldboard 380 at either end
are
elongated, rectangular slots 398, 398' best seen in Figs. 29, 30, 38 and 39.
On the rear surface 384
of moldboard 380 is welded a rectangular, steel slide support or housing 400
having a top wall 402,
bottom wall 404, and rear wall 406 forming a generally U-shaped enclosure
which is larger than
slots or openings 398, 398' on the front of the moldboard section 383. The
slide support or housing
400 and its corresponding slots or openings 398 or 398' are thus aligned along
the first, steel section
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CA 02229783 1998-03-18
383 of the moldboard in this embodiment of the plow. Mounting flanges 354, 356
and reinforcing
flanges 394, 396 extend over top wa11402, along rear wall 406 and thereafter
along bottom wa11404
of housing 400 and are welded thereto to reinforce the entire assembly.
Additional reinforcement
for main plow 312 is provided by L-shaped plates 408 welded to the corner of
housing 400 between
rear wall 406 and bottom wall 404 and to the lower edge of plate 388 (Figs.
38, 39). Plates 408
extend laterally within the spaces between bolt mounts 393 (Fig. 26). In
addition, as shown in Figs.
26-28 and 39, a pair of support skids 410 are each telescopingly mounted in a
mounting box 412
welded to rear wall 406 and to outermost plate 408 at each end of plow 312.
Skids 410, which
include concave shoes, extend downwardly to engage the ground or pavement
surface and support
blade 390 at the proper height above that surface by a series of metal washers
414 stacked on the
shaft 411 of skid 410 (Fig. 39). The extension of skids 410 is limited by stop
pins 416 passed
through an aperture in shaft 411 of the skid. As ground engaging plow blade
390 wears during use,
the plow operator manually removes individual washers 414 from between the
shoe of skid 410 and
box 412 and places them between pin 416 and box 412 keeping the bottom of the
skid shoe even
with the bottom of the plow blade
As will be explained below, slide support or housing 400 is adapted to receive
generally rectangular, inner slide members 470, 470' best seen in Figs. 34,
35, 35A, 35B and 36-39.
When slide members 470, 470' are received within housing 400 (Figs. 28, 38,
39), hinges 442, 442'
extend through slots 398, 398' to support wing extensions 322, 324 on the
front of the main plow.
Also, front walls 478, 478' of housing 400 have a radius of curvature parallel
to that of moldboard
380, and close slots 398, 398' on either end of main plow 312 such that the
snow or other material
being plowed moves upwardly along moldboard 380 from plow blade 390 continues
along front
surface 382 of the moldboard onto the polymeric moldboard section 385 without
interruption and
without packing into the interior of housing 400.
As best seen in Figs. 31-33, each plow wing extension 322, 324 is a
substantial
mirror image of the other, only one being described in detail herein, namely,
plow wing 322.
Substantially the same elements are included in plow wing extension 324 but
are shown with prime
numerals.
Plow wing extension 322 includes a moldboard section 420 formed entirely from
sheet steel having a radius of curvature substantially the same as that for
moldboard 380 and
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CA 02229783 1998-03-18
extending parallel to moldboard 380 when mounted on plow assembly 312 as shown
in Fig. 39.
Wing extension 322 includes an integral, upper flange 422 extending along the
front surface of
flange 386 at the top of moldboard 380 and over slot or opening 398 on the
front surface 382 at the
left end of moldboard 380. A replaceable, steel extension blade 424, also
known as a cutting edge
or wear edge is secured to the front surface of the lower edge of moldboard
420 and extends
generally parallel to plow blade 390, as shown in Fig. 39. Blade 424 engages
the plowed surface
during plowing and may be repaired or replaced when worn. A generally vertical
reinforcing flange
426 extends along the outermost edge 428 of wing extension moldboard 420. The
innermost edge
430 of moldboard 420 is inclined inwardly and outwardly from the position of
upper flange 422.
Extension blade 424 includes a rearwardly extending, triangular reinforcing
flange 425 at its outer
edge which is bolted to the lower extremity of vertical reinforcing flange 426
as shown in Figs. 26
and 28.
Extending parallel to the upper and lower edges of wing extension 322 on the
rear
surface thereof is a tapered, reinforcement housing 432 best seen in Figs. 28
and 31-33. Housing
432 is preferably formed from sheet steel bent into a generally U-shaped
configuration and welded
to the rear surface of steel moldboard 420. Housing 432 is slightly smaller
than both outer housing
400 and inner slide member 470 as will be understood from Fig. 28. Spaced
along the lower portion
of housing 432 are a series of three elongated securing bolts 436a, 436b, 436c
of successively longer
length which extend through cylindrical bolt mounts 438a, 438b, 438c which
correspond in length
to the successively longer bolts 436 and are welded at a downwardly extending
angle to the inner,
rear surface of moldboard 420 and project through the outer surface of the
rear wall of housing 432
as shown in Fig. 39. Bolts 436 are countersunk in and received through
apertures at the upper edge
of blade extension 424 and pass completely through mounts 438 to receive
fastening nuts thereon to
secure the blade extension in position on the front surface of moldboard 420.
With reference to Figs. 31-37, a vertical support plate 440 is welded to the
edges of
the housing 432 at the inner edge of wing extension 332. At the forward most
edge of support plate
440 adjacent the inner edge 430 of moldboard 420, is a vertically oriented
hinge support tube or
hinge cylinder 442 welded to plate 440. Intermediate the ends of support tube
442 are a pair of
spaced hinge plates 444, 446 which are welded to both support tube 442 and
support plate 440 and
extend parallel to one another outwardly away from the inner edge of the wing
extension. As was
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CA 02229783 1998-03-18
the case in embodiment 10 of the plow assembly, and as shown in Figs. 34-36, a
vertical hinge pivot
axis X is provided by support tube 442 while a fluid cylinder pivot axis Y is
provided by aligned
apertures 448 extending through hinge plates 444, 446. Hinge pivot axis X is
offset from fluid
cylinder pivot axis Y by a predetermined distance creating a moment arm
providing torque for
pivoting the wing extension on its hinge axis as will be explained more fully
below.
As is best seen in Figs. 34-37, each plow wing extension 322, 324 is pivotally
mounted to the end of a generally rectangular slide member 470, 470', only one
of which is
described in detail herein. Subassemblies 460, 460', comprising slide member
470 and wing
extension 322, or slide member 470' and wing extension 324, are both adapted
to be slidably
mounted telescopingly within housing 400 on rear surface of main plow
moldboard 380 to allow
extension, retraction and forward angling of plow wing extensions 322, 324 by
fluid power
cylinders 500, 502 as referenced above and explained more fully below.
As shown in Figs. 35A, 35B, each slide member 470, 470' is an elongated beam
having a generally rectangular cross section, formed from welded steel and
including a top wall 472,
rear wall 474, bottom wall 476, and a concave front wall 478. The cross-
sectional shape generally
corresponds to the cross-section shape of housing 400. The radius of curvature
of front wall 478 is
substantially the same as for moldboard 380 such that front wall 478 closes
slot 398, 398' when the
plow wing extensions are in their extended positions or angled forwardly. A
pair of parallel hinge
plates 479, 480 are welded to the top and bottom walls 472, 476, respectively,
on the interior of
slide members 470, 470'. Hinge plates 479, 480 project outwardly from the
outer end of slide
member 470, 470' and provide vertically spaced, vertically aligned apertures
482a, 482b and 484a,
484b in the projecting portion of the hinge plates. On the inner surface of
rear wall 474, a vertically
oriented, U-shaped bent steel inner support 486 extends from top wall 472 to
bottom wall 476.
Spaced, parallel cylinder mount plates 488, 490 are welded to support 486 and
the inner surface of
rear wall 474 as shown in Figs. 35A, 35B. Mount plates 488, 490 include two
pair of vertically
aligned apertures 492a, b and 494a, b which receive pivot pins for mounting
the outer end and inner
end of the pair of fluid cylinders for operating the wing extensions as will
be more fully explained
below. As shown in Figs. 34-37, fluid power cylinder 500a extends into the
interior space of slide
member 470 from its inner end while fluid cylinder 502a is mounted within the
interior space of
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CA 02229783 1998-03-18
slide member 470 and extends out of the outer end of the slide member for
engagement with the
wing extension 322.
Plow wing extensions 322, 324 are pivotally mounted to the outer ends of
elongated
slide members 470, 470', by means of hinge plates 479, 480. As shown in Figs.
34, 35, 36 and 37, a
hinge pin 496 extends through vertically aligned apertures 482a, 482b and
through cylindrical hinge
tube 442 along axis X to provide the hinged movement. Wing extension 322
therefore pivots on
axis X from a position in which moldboard 420 is generally rectilinearly
aligned with concave front
wa11478 of slide member 470 to a forwardly angled position in which moldboard
420 extends at an
obtuse angle to the front wa11478 of slide member 470 (Fig. 37). In addition,
slide members 470
include elongated, synthetic wear pads or strips 498 secured to the outer
surface of rear wall 474
adjacent and along the upper and lower edges of the rear wall to slidably
support the slide members
inside housing 400. Preferably, wear pads 498 are formed from ultra high
molecular weight
(UMHW) polyethylene, although other materials, such as Teflon, steel and the
like could also be
used. As shown in Figs. 38 and 39, however, the bottom wa11476 of slide member
470 engages the
inner surface of bottom wall 404 of housing 400 to slidingly support the slide
member 470 within
the housing using suitable lubricants.
As best seen in Figs. 26, 34, 35, 36, and 37, each subassembly of a slide
member
470, 470' and wing extension 322, 324 is operated between its retracted,
extended and forwardly
angled positions by a pair of extendable, hydraulic fluid power cylinders
500a, 502a and 500b,
502b. Fluid cylinders 500a, 500b include extendable piston rods 504a, 504b
while fluid cylinders
502a, 502b include extendable piston rods 506a, 506b. Fluid cylinders 500a,
500b are longer and
extend piston rods 504a, 504b a greater distance than fluid cylinders 502a,
502b and piston rods
506a, 506b. The inner end of fluid cylinders 500a, 500b are pivotally mounted
by pivot pins 501a,
501b extending between cylinder mount plates 508, 510 welded to the interior
surface of upper wall
402 and bottom wall 404 of slide housing 400 as shown in Fig. 26. A
rectangular aperture is
provided through rear wall 406 adjacent plates 508, 510 for access to the
fluid cylinders. The outer
end of extendable piston rods 504a, 504b is pivotally secured by pivot pins
505a, 505b mounted
through vertically aligned apertures 492a, 492b or 492a', 492b', respectively.
Likewise, fluid
cylinders 502a, 502b are respectively pivotally connected via pivot pins 503a,
503b passed through
vertically aligned apertures 494a, 494b or 494a', 494b' and through the end of
the fluid cylinders.
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CA 02229783 1998-03-18
The outer end of extendable piston rods 506a, 506b are pivotally connected via
hinge pins 507a,
507b passed through the vertically aligned apertures 448 defining axis Y in
hinge plates 444, 446 or
444', 446. Because of the offset between pivot axes X and Y, when fluid
cylinder rods 506a, 506b
are extended from cylinders 502a, 502b, the moment arm of the offset created
by the positioning of
the cylinder rods rotates wing extensions 322, 324 forwardly about hinge pins
496, 496' when slide
members 470, 470' reach their full extension after being pushed fully
outwardly by the extension of
fluid cylinder rod 504a, 504b. Fluid cylinders 500, 502 act to hold and
restrain the wing extensions
322, 324 in the position in which they are located without the need for a
latch assembly of the type
used in embodiment 10 described above.
With reference to Figs. 38 and 39, it will now be understood that the
subassemblies
460, 460' of slide members 470, 470' and their pivotally attached wing plow
extensions 322, 324,
respectively, are telescopingly mounted within the interior of housing 400 for
sliding rectilinear
movement within the outer housing along a common axis. When extension of
either wing 322, or
324 is desired, the respective fluid cylinder 500 is activated by means of a
hydraulic control system
described more fully below to extend piston rod 504 thereby moving slide
member 470 or 470'
outwardly along with wing extensions 322 or 324. Fluid cylinder 500 moves
slide member 470,
470' outwardly to its full extension while moldboard 420 remains substantially
parallel to the front
surface of main plow 312 and its moldboard sections 383, 385. At the position
of full extension,
curved front walls 478, 478' of slide members 470, 470' substantially close
slots 398, 398' along
the front surface of the plow so that the snow or other material being plowed
continues to move
along the moldboard without interruption. In the event it is desired to pivot
one or both of the wing
extensions 322, 324 forwardly, the second fluid cylinder 502a, 502b,
respectively, or both, are
activated to pivot the wings about pivot 496, 496' until the wings are angled
forwardly as shown in
Figs. 27, 36, 37 and 40 such that the entire plow has a U-shaped
configuration. As explained below,
the plow operator simply operates a single switch to extend fluid cylinder
500a, 500b after which
the fluid pressure is automatically transferred to the second fluid cylinders
502a, 502b, respectively,
such that the slide member is fully extended and the wing extensions are
pivoted forwardly all in a
continuous movement or motion. Unlike embodiment 10 of the plow assembly, no
separate stop or
latch mechanisms are necessary to control extension or retraction of slide
members 470, 471 since
such control is automatic based on the amount of extension of the piston rods
from fluid cylinders
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CA 02229783 1998-03-18
500, 502. Likewise, the hydraulic pressure in the fluid cylinders resists
rearward pivoting of the
forwardly angled wing extensions during plowing. In the event an obstacle is
encountered, extreme
pressure created within the fluid cylinders 502a, 502b would be relieved
through the hydraulic
system to prevent rupture of hydraulic lines or damage to any of the
components.
As shown in Fig. 40, each pair of fluid cylinders 500a, 502a or 500b, 502b is
controlled by its own respective set of solenoid operated hydraulic valves and
cooperating hydraulic
relief valves via electrical switches mounted in the cab of the plowing
vehicle. A conventional
hydraulic pump 550 creates hydraulic line pressure which is directed by an
electric solenoid
operated spool valve 552a or 552b through line 554a or 554b to the inner end
of fluid cylinder 500a
or 500b thereby extending piston rod 504a or 504b upon closure of an
appropriate electrical switch
in the vehicle cab by the vehicle/plow operator. This shifts solenoid valve
552a or 552b to the left
or right, respectively, in Fig. 40. Once piston rod 504a or 504b is fully
extended, the buildup of
hydraulic pressure in line 554a or 554b activates hydraulic relief valve 556a
or 556b to allow fluid
pressure through hydraulic line 558a or 558b to fluid cylinder 502a or 502b
causing extension of
piston 506a or 506b thereby pivoting wing extension 322 or 324 forwardly as
shown in Fig. 40.
Thus, the plow operator need only depress a single switch causing fluid
pressure to extend cylinder
500a or 500b and then subsequently cylinder 502a or 502b through the operation
of relief valves
556a, 556b. Release of the switch causes solenoid valves 552a, 552b to return
to their centered
positions thereby holding fluid cylinders 500a, 502a, and/or 500b, 502b in
their extended and
forwardly pivoted positions.
When return of wing extensions 322, 325 to their extended positions and
subsequent
retraction of slide members 470, 470' is desired, however, solenoid valve 552a
or 552b is activated
in the reverse direction by moving or depressing the appropriate electrical
switch shifting the spool
valve to the right or left, respectively, in Fig. 40. Hydraulic pressure is
directed through lines 560a,
560b to the outer end of fluid cylinder 502a or 502b causing retraction of
piston rod 506a or 506b
and pivoting wing 322 or 324 to its extended position from its forwardly
angled position. When
piston rod 506a, 506b is fully retracted, increased hydraulic pressure in line
560a, 560b is directed
through relief valve 562a, 562b and lines 564a, 564b to the outer end of fluid
cylinders 500a, 500b
causing retraction of piston rods 504a, 504b and hence, slide members 470,
470' including wing
extension 322, 324. Again, such sequential retraction of the piston rods in
the fluid cylinders occurs
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CA 02229783 1998-03-18
continuously without the necessity of the operator throwing separate switches
through the operation
of the relief valves 562a, 562b. If desired, cam operated, micro switches
565a, 565b may be
mounted on housing top wal1402 (Figs. 26, 27, 38, 39) to stop extension of the
cylinders 500 and
slide members 470, 470', followed by activation of a separate switch to cause
extension of cylinders
502. Micro switches 565a, 565b each include a flexible strap which extends
through an aperture in
top wall 402 of housing 400 and flexes away from the plunger on an electrical
switch when slide
member 470, 470' is extended, but is flexed into contact with the switch
plunger when the slide
member is retracted.
As shown in Fig. 40, valving for operating the fluid cylinders 342, 344 to
pivot the
plow assembly about support 314 and axis 362 to the left or right is provided
through solenoid
operated valve 566 which is shifted to the right by operation of an electrical
switch to angle the
plow assembly to the left, and shifted to the right through the reversal of
the same switch to angle
the plow assembly to the right with fluid cylinder 344 through hydraulic line
570. Appropriate
relief valves 572, 574 are connected, respectively, to lines 568, 570 in the
event pressure on the
plow during plowing forces the plow in the opposite pivotal direction and
creates extreme pressure
within the hydraulic system.
Likewise, as shown in phantom in Fig. 40, a solenoid operated valve 576 and an
electrically operated check valve 579 may be shifted to the left to activate
the lift cylinder 376 in the
event such a cylinder is included on the support 314. Retuln of check valve
579 to its right-hand
position retains cylinder 376 in its extended position. Similarly, to retract
cylinder 376, solenoid
operated valve 577 and check valve 578 are shifted to the left, after which
release of check valve
578 holds cylinder 376 in its retracted position.
As will also be appreciated, it is also possible to support the plow assembly
including
main plow 12 or 312 and wing extensions 22, 24 or 322, 324 on a support other
than support frame
14 or 314 and intermediate support 16 or 316 at the front of a vehicle. For
example, should the
plow be used on a grader, an overhead beam may include downwardly extending
rods or other
supports which engage rear mounting flanges 54, 56 or 354, 356 from above to
support the
assembly in the normal horizontal position shown in the drawings. Other
supports such as bulldozer
type support arms extending from the rear of the plow to a support frame on a
vehicle may also be
used with this plow assembly.
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CA 02229783 1998-03-18
While several forms of the invention have been shown and described, other
forrns
will now be apparent to those skilled in the art. Therefore, it will be
understood that the
embodiments shown in the drawings and described above are merely for
illustrative purposes, and
are not intended to limit the scope of the invention which is defined by the
claims which follow as
interpreted according to the principals of patent law, including the Doctrine
of Equivalents.
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