U.S. patent application number 14/591216 was filed with the patent office on 2016-07-07 for split walking beams for raising and lowering respective sides of a vehicle or implement frame to control a tilt angle or height thereof.
The applicant listed for this patent is Ashley Sawatsky. Invention is credited to Ashley Sawatsky.
Application Number | 20160194853 14/591216 |
Document ID | / |
Family ID | 56286202 |
Filed Date | 2016-07-07 |
United States Patent
Application |
20160194853 |
Kind Code |
A1 |
Sawatsky; Ashley |
July 7, 2016 |
Split Walking Beams for Raising and Lowering Respective Sides of a
Vehicle or Implement Frame to Control a Tilt Angle or Height
Thereof
Abstract
Vehicles or implements feature walking beam assemblies each
having a front wheel and rear wheel carried adjacent opposite ends
of the walking beam on opposite sides of a pivot point thereof. The
conventional single beam is replaced by a split beam arrangement in
which front and rear beams are pivotal relative to one another by
an actuator, whereby changing the angle between the front and rear
beams lifts or lowers the main pivot of the walking beam in order
to adjust the height of the respective side of the vehicle frame.
The split walking beam can be used to adjust the tilt angle of a
scraper blade or other ground working arrangement in a land leveler
or other earth working machine.
Inventors: |
Sawatsky; Ashley; (Altona,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sawatsky; Ashley |
Altona |
|
CA |
|
|
Family ID: |
56286202 |
Appl. No.: |
14/591216 |
Filed: |
January 7, 2015 |
Current U.S.
Class: |
172/799.5 ;
172/421; 29/897.2 |
Current CPC
Class: |
E02F 3/844 20130101;
E02F 3/7677 20130101; E02F 9/024 20130101 |
International
Class: |
E02F 9/02 20060101
E02F009/02; E02F 3/76 20060101 E02F003/76 |
Claims
1. A vehicle or implement comprising: a frame situated having
opposing sides disposed on opposing sides of a longitudinal plane
that runs in a longitudinal direction of the vehicle or implement;
a pair of wheel assemblies, each being attached to the frame
adjacent a respective one of the opposing sides thereof so as to
reside on and rollably carry a respective one of the opposing sides
of the longitudinal plane, at least one of the wheel assemblies
comprising: a split walking beam assembly pivotally coupled to the
frame for pivotal movement of the split walking beam assembly about
a first walking beam pivot axis lying transversely to the
longitudinal direction, the split walking beam assembly comprising:
a front beam having front and rear ends spaced apart in the
longitudinal direction; and a rear beam having forward and rearward
ends spaced apart in the longitudinal direction, the front end of
the front beam being situated forwardly of the forward end of the
rear beam in the longitudinal direction, the rearward end of the
rear beam being situated rearwardly of the rear end of the front
beam in the longitudinal direction, the front and rear beams being
coupled together adjacent the rear and forward ends thereof, and
the rear beam being pivotal relative to the front beam about a
second walking beam pivot axis lying transversely of the
longitudinal direction; a front wheel rotatably coupled to the
front beam adjacent the front end thereof; a rear wheel rotatably
coupled to the rear beam adjacent the rearward end thereof; and a
wheel assembly actuator coupled between the front and rear beams of
the split walking beam assembly and operable to pivot the front and
rear beams relative to one another to adjust an angle measured
between the front and rear beams at an underside thereof, whereby
an increase of the angle lowers the respective side of the frame
and respective lateral end of the blade and a decrease of the angle
raises the respective side of the frame and the respective lateral
end of the blade.
2. The vehicle or implement of claim 1 comprising: a tongue having
fore and aft ends spaced apart in the longitudinal direction; a
hitch connector at the fore end of said tongue for coupling of the
hitch connector to a hitch of a towing vehicle; a ground working
arrangement coupled to the tongue adjacent the rear end thereof
with opposing lateral ends of the ground working arrangement
disposed on opposing sides of the longitudinal plane of the vehicle
or implement at outboard positions spaced laterally from said
longitudinal plane; wherein the frame is situated behind the ground
working arrangement in the longitudinal direction, whereby
increasing the angle of each wheel assembly lowers the respective
lateral end of the ground working arrangement and decreasing the
angle raises the respective lateral end of the blade of the ground
working arrangement.
3. The vehicle or implement of claim 2 further comprising: a
pivotal connection between the frame and the ground working
arrangement that allows relative pivoting between the frame and the
ground working arrangement about a pitch axis that lies in the
transverse direction; and a pitch actuator coupled between the
frame and the blade and operable to tilt the ground working
arrangement relative to the frame about the pitch axis.
4. The vehicle or implement of claim 2 wherein the frame comprises
a cross-member lying transversely to the longitudinal plane and a
pair of rearward reaching frame members extending therefrom in the
longitudinal direction adjacent opposing ends of the cross-member
on the opposing sides of the longitudinal plane, each rearward
reaching frame member having a respective one of the wheel
assemblies connected thereto and split walking beam assembly being
pivotally connected to the respective rearward reaching frame
member.
5. The vehicle or implement of claim 4 wherein the rearward
reaching frame members are respectively connected to the
cross-member at opposing ends thereof, and each extend forwardly
past the cross-member to attach to the ground working
arrangement.
6. The vehicle or implement of claim 2 wherein the ground working
arrangement comprises a scraper blade lying transversely of the
longitudinal plane with opposing ends of the blade defining the
lateral ends of the ground working arrangement on the opposing
sides of the longitudinal plane.
7. The vehicle or implement of claim 1 wherein the wheel assemblies
both comprise a respective walking beam assembly, and the walking
beam assemblies are arranged to be adjustable into different
respective angles, thereby adjusting an angular position of the
frame about a roll axis that extends in the longitudinal
direction.
8. The vehicle or implement of claim 7 comprising a control system
operable to control movement of the wheel assembly actuators.
9. The vehicle or implement of claim 8 wherein the control system
is arranged to automatically extend one of the walking beam
actuators while collapsing the other, thereby increasing the angle
between the front and rear beams of one walking beam assembly while
decreasing the angle between the front and rear beams of the other
walking beam assembly so as to raise one side of the frame while
lowering the other side of the frame.
10. The vehicle or implement of claim 9 wherein: each walking beam
actuator comprises a hydraulic cylinder with a respective extension
port and respective retraction port; the control system comprises a
four-way, three-position, spring centered directional valve with a
pressure port for coupling to the output of a hydraulic pump, a
return port for coupling with a hydraulic fluid reservoir, and a
pair of output ports connected to either the extension ports or the
retraction ports of the walking beam actuators; and a hydraulic
connection line coupling together the other of the extension ports
or the retraction ports of the walking beam actuators.
11. The vehicle or implement of claim 10 wherein the directional
valve is a double solenoid directional valve arranged to use
electronic signals to control a position of the valve.
12. The vehicle or implement of claim 8 comprising a monitoring
system arranged to monitor an orientation of the frame about a
longitudinal axis, and linked to the control system to
automatically control the walking beam actuators and adjust the
orientation of the frame.
13. The vehicle or implement of claim 1 wherein the first walking
beam pivot axis and second walking beam pivot axis of each wheel
assembly are coincident with one another.
14. The vehicle or implement of claim 1 wherein the first and
second beams of each wheel assembly both pivot about the second
walking beam pivot axis.
15. A method of providing tilt or height adjustment capabilities to
a vehicle or implement that is at least partially supported by a
pair of walking beam wheel assemblies are disposed on opposing
sides of a longitudinal plane of the vehicle or implement and each
feature front and rear wheels that are respectively mounted
adjacent front and rear ends a single walking beam that is
pivotally coupled to a frame of the vehicle or implement at a
longitudinally intermediate location on the walking beam for
pivoting of the walking beam about a walking beam pivot axis lying
transversely to the central longitudinal plane, the method
comprising: replacing at least one walking beam assembly with a
respective split walking beam assembly that is pivotally coupled to
the frame for movement about the same walking beam pivot axis, and
that comprises: a front beam having front and rear ends spaced
apart in a longitudinal direction in which the central longitudinal
plane extends; and a rear beam having forward and rearward ends
spaced apart in the longitudinal direction, the front end of the
front beam being situated forwardly of the forward end of the rear
beam in the longitudinal direction, the rearward end of the rear
beam being situated rearwardly of the rear end of the front beam in
the longitudinal direction, the front and rear beams being coupled
together adjacent the rear and forward ends thereof, and the rear
beam being pivotal relative to the front beam about a second pivot
axis lying transversely of the longitudinal direction; a front
wheel rotatably coupled to the front beam adjacent the front end
thereof; a rear wheel rotatably coupled to the rear beam adjacent
the rearward end thereof; and a wheel assembly actuator coupled
between the front and rear beams of the split walking beam assembly
and operable to pivot the front and rear beams relative to one
another to adjust an angle measured between the front and rear
beams at an underside thereof, whereby, with the front and rear
wheels on a ground surface, an increase of the angle surface lowers
the respective side of the frame and respective lateral end of the
blade and a decrease of the angle raises the respective side of the
frame and the respective lateral end of the blade.
16. The method of claim 15 comprising replacing each walking beam
assembly with a respective split walking beam assembly, and further
comprising equipping the vehicle or implement with a control system
operable to control movement of the wheel assembly actuators.
17. The method of claim 16 wherein the control system is arranged
to extend one of the walking beam actuators while collapsing the
other, thereby increasing the angle between the front and rear
beams of one walking beam assembly while decreasing the angle
between the front and rear beams of the other walking beam assembly
so as to raise one side of the frame while lowering the other side
of the frame.
18. The method of claim 17 wherein each walking beam actuator
comprises a hydraulic cylinder with a respective extension port and
respective retraction port and the control system comprises a
four-way, three-position, spring centered directional valve, the
method comprises coupling a pressure port of the directional valve
to an output of a hydraulic pump, coupling a return port of the
directional valve with a hydraulic fluid reservoir, fluidly
connecting output ports of the directional valve to either the
extension ports or the retraction ports of the walking beam
actuators, and fluidly connecting the walking beam actuators
together at the other of the extension ports or the retractions
ports.
19. The method of claim 18 wherein the directional valve is a
double solenoid directional valve arranged to use electronic
signals to control a position of the valve.
20. The method of claim 16 comprising equipping the vehicle or
implement with a tilt monitoring system arranged to monitor an
angular position of the frame about a roll axis that extends in the
longitudinal direction, and connecting the tilt monitoring system
to the control system to automatically control the walking beam
actuators and adjust the angular position.
21. The method of claim 15 wherein the second pivot axis of each
split walking beam assembly is coincident with the respective
walking beam pivot axis.
22. The method of claim 15 wherein the first and second beams of
each split walking beam assembly both pivot about the second pivot
axis.
23. A towable ground working implement comprising: a tongue having
fore and aft ends spaced apart in a longitudinal direction; a hitch
connector at the fore end of said tongue for coupling of the hitch
connector to a hitch of a towing vehicle; a scraper blade coupled
to the tongue adjacent the rear end thereof and lying transversely
to the longitudinal direction so as to place opposite lateral ends
of the blade on opposing sides of a central longitudinal plane of
the implement at outboard positions spaced laterally from said
central longitudinal plane; a frame situated behind the blade in
the longitudinal direction with opposite sides of the frame
disposed on the opposing sides of the longitudinal plane; a pair of
wheel assemblies, each being attached to the frame adjacent a
respective one of the opposing sides thereof so as to reside on a
respective one of the opposing sides of the longitudinal plane, at
least one of the wheel assemblies comprising: a split walking beam
assembly pivotally coupled to the frame for pivotal movement of the
split walking about a first walking beam pivot axis lying
transversely to the longitudinal direction, the split walking beam
assembly comprising: a front beam having front and rear ends spaced
apart in the longitudinal direction; and a rear beam having forward
and rearward ends spaced apart in the longitudinal direction, the
front end of the front beam being situated forwardly of the forward
end of the rear beam in the longitudinal direction, the rearward
end of the rear beam being situated rearwardly of the rear end of
the front beam in the longitudinal direction, the front and rear
beams being coupled together adjacent the rear and forward ends
thereof, and the beam being pivotal relative to the front beam
about a second walking beam pivot axis lying transversely of the
longitudinal direction; a front wheel rotatably coupled to the
front beam adjacent the front end thereof; a rear wheel rotatably
coupled to the rear beam adjacent the rearward end thereof; and a
wheel assembly actuator coupled between the front and rear beams of
the split walking beam assembly and operable to pivot the front and
rear beams relative to one another to adjust an angle measured
between the front and rear beams at an underside thereof, whereby,
with the front and rear wheels on a ground surface, an increase of
the angle lowers the respective side of the frame and respective
lateral end of the blade and a decrease of the angle raises the
respective side of the frame and the respective lateral end of the
blade, thereby adjusting an angular tilt position of the blade
about a roll axis that extends in the longitudinal direction.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to vehicles or
implements employing walking beam assemblies each having a front
wheel and rear wheel carried adjacent opposite ends of the walking
beam on opposite sides of a pivot point thereof, and more
particularly to a split walking beam assembly in which the
conventional single-beam is replaced is replaced with a multi-piece
beam assembly with front and rear beams that are pivotal relative
to one another by an actuator, whereby changing the angle between
the front and rear beams lifts or lowers the main pivot of the
walking beam to adjust the height of the respective side of the
vehicle frame.
BACKGROUND
[0002] It has previously been proposed in the prior art to provide
a towed ground leveling or ground scraping implement in which a
tilt angle of the scraper blade about a longitudinal fore-aft axis
of the implement is adjustable by raising and lowering a side of
the frame at an outboard location spaced laterally outward from a
longitudinal mid-plane in which the fore-aft axis is located.
[0003] Such an implement is disclosed in U.S. Pat. No. 4,055,222,
in which a single wheel is provided at each side of a frame that is
situated behind a scraper blade carried on a pull tongue of the
towable implement. On one side of the frame, the axle of the
respective wheel is attached to an inner one of a pair of
telescopically nested tubes that stand upward from the frame, and
an upright hydraulic cylinder has its respective ends coupled to
the vehicle frame and the top end of the inner tube, whereby
extending the cylinder raises the inner tube in order to lift the
respective wheel relative to the frame, thereby lowering the
respective side of the frame to tilt the respective end of the
blade downwardly toward the ground relative to the opposing end of
the blade.
[0004] U.S. Pat. No. 4,189,009 discloses another tilt-adjustable
scraper with a single wheel on each side of the frame. In this
reference, a single axle carrying the two wheels is pivotally
coupled to a rear end of a frame disposed behind the scraper blade
for relative pivoting between the axle and frame on a pivot axis
residing in the central fore-aft longitudinal plane of the
implement. A hydraulic cylinder has one end coupled to an upright
bracket at the center of the axle, and the other end coupled to an
outboard point on the frame, whereby extension and collapse of the
cylinder tilts controls a tilt angle of the axle relative to the
frame and blade in order to adjust the blade angle relative to the
ground.
[0005] U.S. Pat. No. 2,734,293 also discloses another example of a
tilt-adjustable scraper with a single wheel at each end of an axle
that is pivotally coupled to the frame for hydraulically actuated
movement between the frame and axle about a tilt axis.
[0006] U.S. Patent Application Publication 2012/0311894 discloses
another example of a tilt-adjustable scraper with a single wheel at
each end of an axle or subframe that is pivotally coupled to the
main frame for hydraulically actuated movement relative thereto in
order to set the blade angle.
[0007] A potential drawback of the forgoing prior art is that,
because the towed frame is carried only by a single wheel on each
side of the frame, a rock or other ground protrusion in the path of
either wheel will raise the frame and blade by the full height of
the rock as the wheel rides overtop of same. It is known that the
use of walking beam axles can reduce the effective of such ground
deviations, where front and rear wheels carried at respective ends
of a beam pivotally coupled to the frame can `walk` over such an
obstacle, as the front wheel can ride at least partially over the
obstruction before the rear wheel reaches the obstruction.
[0008] However, the prior art provides no teaching or suggestion of
how to implement a walking beam in a setting in which the wheel
position is also to be controlled relative to the frame for use in
controlling a tilt angle of the blade.
[0009] The forgoing prior art implements each move at least one of
the wheels relative to the frame of the implement in order change
the tilt angle of the frame to which the blade is attached. In each
of the above cases, the blade and frame are pivotally connected for
relative movement about a transverse axis to raise and lower the
blade relative to the frame, but the blade and frame remain in a
matching orientation with one another relative to the tilt
axis.
[0010] Another group of adjustable-tilt scrapers have fixed wheel
axles that do not move relative to the frame, and instead employ a
mechanism for tilting the blade relative to the frame. Examples of
such scrapers are disclosed in U.S. Pat. Nos. 2,284,550; 2,520,266;
and 2,883,777.
[0011] In addition to the forgoing references concerning towed
scraper implements, Applicant is also aware of U.S. Patent
Application Publication 2012/0239258, teaches a self-propelled
grader which employs a gyroscope together with blade slope and
blade tilt sensors to monitor the blade position and automatically
adjust same.
[0012] As these references adjustment the blade relative to the
frame instead of adjusting the wheels relative to the frame, they
also lack any teaching or suggestion of how to combine the
advantages of a walking beam arrangement into a blade-tilting
arrangement relying on controlled movement between the frame and
wheels.
[0013] Applicant has developed an adjustable height walking beam
solution that can be employed on the frame of a scraper implement
to address the identified shortcoming of the prior art, and that
can also be employed to advantageous effect on other vehicle or
implement types.
SUMMARY OF THE INVENTION
[0014] According to one aspect of the invention there is provided a
vehicle or implement comprising:
[0015] a frame situated having opposing sides disposed on opposing
sides of a longitudinal plane that runs in a longitudinal direction
of the vehicle or implement;
[0016] a pair of wheel assemblies, each being attached to the frame
adjacent a respective one of the opposing sides thereof so as to
reside on and rollably carry a respective one of the opposing sides
of the longitudinal plane, at least one of the wheel assemblies
comprising: [0017] a split walking beam assembly pivotally coupled
to the frame for pivotal movement of the split walking beam
assembly about a first walking beam pivot axis lying transversely
to the longitudinal direction, the split walking beam assembly
comprising: [0018] a front beam having front and rear ends spaced
apart in the longitudinal direction; and [0019] a rear beam having
forward and rearward ends spaced apart in the longitudinal
direction, the front end of the front beam being situated forwardly
of the forward end of the rear beam in the longitudinal direction,
the rearward end of the rear beam being situated rearwardly of the
rear end of the front beam in the longitudinal direction, the front
and rear beams being coupled together adjacent the rear and forward
ends thereof, and the rear beam being pivotal relative to the front
beam about a second walking beam pivot axis lying transversely of
the longitudinal direction; [0020] a front wheel rotatably coupled
to the front beam adjacent the front end thereof; [0021] a rear
wheel rotatably coupled to the rear beam adjacent the rearward end
thereof; and [0022] a wheel assembly actuator coupled between the
front and rear beams of the split walking beam assembly and
operable to pivot the front and rear beams relative to one another
to adjust an angle measured between the front and rear beams at an
underside thereof, whereby an increase of the angle lowers the
respective side of the frame and respective lateral end of the
blade and a decrease of the angle raises the respective side of the
frame and the respective lateral end of the blade.
[0023] In one embodiment, there is provided:
[0024] a tongue having fore and aft ends spaced apart in the
longitudinal direction;
[0025] a hitch connector at the fore end of said tongue for
coupling of the hitch connector to a hitch of a towing vehicle;
[0026] a ground working arrangement coupled to the tongue adjacent
the rear end thereof with opposing lateral ends of the ground
working arrangement disposed on opposing sides of the longitudinal
plane of the vehicle or implement at outboard positions spaced
laterally from said longitudinal plane;
[0027] wherein the frame is situated behind the ground working
arrangement in the longitudinal direction, whereby increasing the
angle of each wheel assembly lowers the respective lateral end of
the ground working arrangement and decreasing the angle raises the
respective lateral end of the blade of the ground working
arrangement.
[0028] Preferably there is provided:
[0029] a pivotal connection between the frame and the ground
working arrangement that allows relative pivoting between the frame
and the ground working arrangement about a pitch axis that lies in
the transverse direction; and
[0030] a pitch actuator coupled between the frame and the blade and
operable to tilt the ground working arrangement relative to the
frame about the pitch axis.
[0031] Preferably the frame comprises a cross-member lying
transversely to the longitudinal plane and a pair of rearward
reaching frame members extending therefrom in the longitudinal
direction adjacent opposing ends of the cross-member on the
opposing sides of the longitudinal plane, each rearward reaching
frame member having a respective one of the wheel assemblies
connected thereto and split walking beam assembly being pivotally
connected to the respective rearward reaching frame member.
[0032] Preferably the rearward reaching frame members are
respectively connected to the cross-member at opposing ends
thereof, and each extend forwardly past the cross-member to attach
to the ground working arrangement.
[0033] In one embodiment, the ground working arrangement comprises
a scraper blade lying transversely of the longitudinal plane with
opposing ends of the blade defining the lateral ends of the ground
working arrangement on the opposing sides of the longitudinal
plane.
[0034] Preferably the wheel assemblies both comprise a respective
walking beam assembly, and the walking beam assemblies are arranged
to be adjustable into different respective angles, thereby
adjusting an angular position of the frame about a roll axis that
extends in the longitudinal direction.
[0035] Preferably there is provided a control system operable to
control movement of the wheel assembly actuators.
[0036] Preferably the control system is arranged to automatically
extend one of the walking beam actuators while collapsing the
other, thereby increasing the angle between the front and rear
beams of one walking beam assembly while decreasing the angle
between the front and rear beams of the other walking beam assembly
so as to raise one side of the frame while lowering the other side
of the frame.
[0037] Preferably, each walking beam actuator comprises a hydraulic
cylinder with a respective extension port and respective retraction
port;
[0038] the control system comprises a four-way, three-position,
spring centered directional valve with a pressure port for coupling
to the output of a hydraulic pump, a return port for coupling with
a hydraulic fluid reservoir, and a pair of output ports connected
to either the extension ports or the retraction ports of the
walking beam actuators; and
[0039] a hydraulic connection line coupling together the other of
the extension ports or the retraction ports of the walking beam
actuators.
[0040] Preferably the directional valve is a double solenoid
directional valve arranged to use electronic signals to control a
position of the valve.
[0041] Preferably there is provided a monitoring system arranged to
monitor an orientation of the frame about a longitudinal axis, and
linked to the control system to automatically control the walking
beam actuators and adjust the orientation of the frame.
[0042] Preferably the first walking beam pivot axis and second
walking beam pivot axis of each wheel assembly are coincident with
one another.
[0043] Preferably the first and second beams of each wheel assembly
both pivot about the second walking beam pivot axis.
[0044] According to a second aspect of the invention, there is
provided a method of providing tilt or height adjustment
capabilities to a vehicle or implement that is at least partially
supported by a pair of walking beam wheel assemblies are disposed
on opposing sides of a longitudinal plane of the vehicle or
implement and each feature front and rear wheels that are
respectively mounted adjacent front and rear ends a single walking
beam that is pivotally coupled to a frame of the vehicle or
implement at a longitudinally intermediate location on the walking
beam for pivoting of the walking beam about a walking beam pivot
axis lying transversely to the central longitudinal plane, the
method comprising:
[0045] replacing at least one walking beam assembly with a
respective split walking beam assembly that is pivotally coupled to
the frame for movement about the same walking beam pivot axis, and
that comprises: [0046] a front beam having front and rear ends
spaced apart in a longitudinal direction in which the central
longitudinal plane extends; and [0047] a rear beam having forward
and rearward ends spaced apart in the longitudinal direction, the
front end of the front beam being situated forwardly of the forward
end of the rear beam in the longitudinal direction, the rearward
end of the rear beam being situated rearwardly of the rear end of
the front beam in the longitudinal direction, the front and rear
beams being coupled together adjacent the rear and forward ends
thereof, and the rear beam being pivotal relative to the front beam
about a second pivot axis lying transversely of the longitudinal
direction; [0048] a front wheel rotatably coupled to the front beam
adjacent the front end thereof; [0049] a rear wheel rotatably
coupled to the rear beam adjacent the rearward end thereof; and
[0050] a wheel assembly actuator coupled between the front and rear
beams of the split walking beam assembly and operable to pivot the
front and rear beams relative to one another to adjust an angle
measured between the front and rear beams at an underside thereof,
whereby, with the front and rear wheels on a ground surface, an
increase of the angle surface lowers the respective side of the
frame and respective lateral end of the blade and a decrease of the
angle raises the respective side of the frame and the respective
lateral end of the blade.
[0051] The method may include replacing each walking beam assembly
with a respective split walking beam assembly, and further
comprising equipping the vehicle or implement with a control system
operable to control movement of the wheel assembly actuators.
[0052] The control system may be arranged to extend one of the
walking beam actuators while collapsing the other, thereby
increasing the angle between the front and rear beams of one
walking beam assembly while decreasing the angle between the front
and rear beams of the other walking beam assembly so as to raise
one side of the frame while lowering the other side of the
frame.
[0053] In such instance, the walking beam actuator may comprise a
hydraulic cylinder with a respective extension port and respective
retraction port and the control system may comprise a four-way,
three-position, spring centered directional valve, and the method
may comprise coupling a pressure port of the directional valve to
an output of a hydraulic pump, coupling a return port of the
directional valve with a hydraulic fluid reservoir, coupling output
ports of the directional valve to either the extension ports or the
retraction ports of the walking beam actuators, and coupling the
walking beam actuators together at the other of the extension ports
or the retractions ports.
[0054] The directional valve may be a double solenoid directional
valve arranged to use electronic signals to control a position of
the valve.
[0055] The method may include equipping the vehicle or implement
with a tilt monitoring system arranged to monitor an angular
position of the frame about a roll axis that extends in the
longitudinal direction, and connecting the tilt monitoring system
to the control system to automatically control the walking beam
actuators and adjust the angular position.
[0056] Preferably the second pivot axis of each split walking beam
assembly is coincident with the respective walking beam pivot
axis.
[0057] Preferably the first and second beams of each split walking
beam assembly both pivot about the second pivot axis.
[0058] According to a third aspect of the invention, there is
provided a towable ground working implement comprising:
[0059] a tongue having fore and aft ends spaced apart in a
longitudinal direction;
[0060] a hitch connector at the fore end of said tongue for
coupling of the hitch connector to a hitch of a towing vehicle;
[0061] a scraper blade coupled to the tongue adjacent the rear end
thereof and lying transversely to the longitudinal direction so as
to place opposite lateral ends of the blade on opposing sides of a
central longitudinal plane of the implement at outboard positions
spaced laterally from said central longitudinal plane;
[0062] a frame situated behind the blade in the longitudinal
direction with opposite sides of the frame disposed on the opposing
sides of the longitudinal plane;
[0063] a pair of wheel assemblies, each being attached to the frame
adjacent a respective one of the opposing sides thereof so as to
reside on a respective one of the opposing sides of the
longitudinal plane, at least one of the wheel assemblies
comprising: [0064] a split walking beam assembly pivotally coupled
to the frame for pivotal movement of the split walking about a
first walking beam pivot axis lying transversely to the
longitudinal direction, the split walking beam assembly comprising:
[0065] a front beam having front and rear ends spaced apart in the
longitudinal direction; and [0066] a rear beam having forward and
rearward ends spaced apart in the longitudinal direction, the front
end of the front beam being situated forwardly of the forward end
of the rear beam in the longitudinal direction, the rearward end of
the rear beam being situated rearwardly of the rear end of the
front beam in the longitudinal direction, the front and rear beams
being coupled together adjacent the rear and forward ends thereof,
and the beam being pivotal relative to the front beam about a
second walking beam pivot axis lying transversely of the
longitudinal direction; [0067] a front wheel rotatably coupled to
the front beam adjacent the front end thereof; [0068] a rear wheel
rotatably coupled to the rear beam adjacent the rearward end
thereof; and [0069] a wheel assembly actuator coupled between the
front and rear beams of the split walking beam assembly and
operable to pivot the front and rear beams relative to one another
to adjust an angle measured between the front and rear beams at an
underside thereof, whereby, with the front and rear wheels on a
ground surface, an increase of the angle lowers the respective side
of the frame and respective lateral end of the blade and a decrease
of the angle raises the respective side of the frame and the
respective lateral end of the blade, thereby adjusting an angular
tilt position of the blade about a roll axis that extends in the
longitudinal direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0070] One embodiment of the invention will now be described in
conjunction with the accompanying drawings in which:
[0071] FIG. 1A is an overhead plan view of a land leveler of the
present invention with a blade thereof residing in a level
horizontal orientation parallel to the ground.
[0072] FIG. 1B is left side elevational view of the land leveler of
FIG. 1A.
[0073] FIG. 1C is a rear elevational view of the land leveler of
FIG. 1A.
[0074] FIG. 2A is an overhead plan view of the land leveler of FIG.
1A with the blade residing in a tilted orientation in which the end
of the blade on a left side of the machine is lowered into closer
proximity to the ground than the opposing end of the blade on the
right side of the machine.
[0075] FIG. 2B is a right side elevational view of the land leveler
of FIG. 2A.
[0076] FIG. 2C is a left side elevational view of the land leveler
of FIG. 2A.
[0077] FIG. 2D is a rear elevational view of the land leveler of
FIG. 2A.
[0078] FIG. 2E is a partial rear perspective view of the land
leveler of FIG. 2A from the right side thereof.
[0079] FIG. 2F is a partial rear perspective view of the land
leveler of FIG. 2A from the left side thereof.
[0080] FIG. 3A is a schematic overhead plan view illustrating a
hydraulic control system for controlling the tilt angle of the land
leveler of FIG. 1A.
[0081] FIG. 3B is side elevational view of select components of the
hydraulic control system of FIG. 3A.
[0082] FIG. 3C is a schematic perspective view of the hydraulic
control system components of FIG. 3B.
[0083] FIG. 3D is another schematic perspective view of the
hydraulic control system components of FIG. 3B.
[0084] FIG. 4 is a closeup perspective view of a split walking beam
tandem wheel assembly of the land leveler of FIG. 1A with wheels
thereof omitted for illustrative purposes.
[0085] FIG. 5 is a perspective view of a conventional walking beam
tandem wheel assembly for which the split walking beam tandem
wheels assembly of FIG. 4 may be substituted in order to provide a
tilt or height adjustment functionality to a vehicle or implement
previously lacking same.
[0086] FIGS. 6A through 6E are various views of a directional valve
and manifold assembly of the hydraulic control system of FIG.
3.
[0087] In the drawings like characters of reference indicate
corresponding parts in the different figures.
DETAILED DESCRIPTION
[0088] FIGS. 1A through 2D illustrate a towed land leveler
implement 10 of the present invention. The implement 10 features a
pull tongue 12 equipped with a hitch connector 14 at a fore end of
the tongue for coupling to the hitch of a tow vehicle for pulling
of the implement along the ground in forward working direction F. A
box blade assembly 16 is rigidly attached to the tongue and
features a rear blade 18 spanning transversely of the tongue 12 in
a position therebeneath adjacent an aft end 18 thereof that lies
opposite to the fore end at which the hitch connector 14 is
mounted.
[0089] When the implement is in a level-blade configuration holding
the box blade parallel to the underlying ground, the pull tongue 12
lies in a vertically oriented central longitudinal plane of the
implement. The rear blade 18 spans from one side of the central
longitudinal plane to the other in an orientation perpendicular
thereto, thus placing each lateral end of the rear blade 18 at an
outboard location horizontally outward from the tongue 12. At each
end of the blade 18, a respective planar end wall 20 projects
forwardly therefrom in a plane parallel to the tongue 12. Box blade
structures of this type are known in conventional land leveler
designs, and thus are not described herein in further detail. As is
also well known in the art, the tongue 12 extends forwardly from
the box blade assembly 16 to the hitch connector 14 at the fore end
of the tongue, which therefore defines the forward or leading end
of the overall machine by which it is pulled by a tractor or other
suitable tow vehicle.
[0090] With reference to FIG. 1A, a frame assembly 22 resides
behind the blade 18 so as to trail the same during pulling of the
implement by a tow vehicle. The frame 22 features a main
cross-member 24 lying parallel to the blade 18 and perpendicularly
transverse to the tongue 12. The cross-member 24 spans across the
central longitudinal plane of the machine to place each of the
cross-member 24 at an outboard location spaced laterally outward
from the central longitudinal plane, just like the blade 18. The
length of the cross-member between these two ends is parallel to,
but shorter than, the length of the blade 18, whereby each end of
the cross-member 24 lies inboard of the respective end wall 20 of
the box blade assembly 16. A respective longitudinal frame member
26 is attached to the main cross-beam at each end thereof, lies
perpendicular to the cross-member 24, and extends both forwardly
and rearwardly therefrom. As best seen in the plan views of FIGS.
1A and 2A, the relative positioning of the cross-member 24 and each
longitudinal member 26 fixed thereto may be reinforced by a
respective gusset plate 27.
[0091] The forward end of each longitudinal frame member 26
features a pivotal connection 28 to the blade 18, which enables
pivoting of the frame assembly 22 relative to the box blade
assembly 16 about a pivot axis that lies perpendicularly transverse
to the tongue and parallel to the blade 18 and the main
cross-member 24. The pivotal connections 28 of the two longitudinal
frame members 26 to the blade 18 share this same pivot axis, which
due to its orientation, may be considered to be a pitch axis P of
the implement 10. As perhaps best shown in FIGS. 2E and 2F, each of
these pivotal connections 28 may be formed by pinning of the
respective longitudinal frame member 26 to a respective pair of
rearwardly extending lugs 30 on the rear face of the blade 18. A
central lug 32 is fixed on the main cross-beam 24 and projects
rearwardly therefrom at a midpoint therealong, and one end of a
hydraulic cylinder actuator 34 is pivotally coupled to the lug 32
by a pivot pin whose pivot axis is parallel to the pitch axis P.
The opposing end of the hydraulic cylinder actuator 34 is likewise
pivotally pinned to a pair of mounting brackets 36 on the rear of
the blade 18, as perhaps best shown in FIG. 2E. Extension and
retraction of the actuator 34 thus pivots box blade assembly 16 and
attached tongue 12 relative to the frame 12 about the pitch axis P,
for example in order to lower the blade 18 down into engagement
with the ground to perform a ground-working, earth-moving
operation, or to raise the blade out of contact with the ground for
transport of the machine.
[0092] Each longitudinal frame member 26 defines a respective side
of the frame 22 on a respective one of the two opposing sides of
the central longitudinal plane of the machine. Near the rearward
end of each longitudinal frame member 26 that lies distally of the
cross-member 24, a pivot pin or stub shaft 38 passes transversely
through the longitudinal frame member 26 in a direction parallel to
the pitch axis P, and projects outwardly from the longitudinal
frame member 26 through front and rear beams 40, 42 of a respective
split walking beam assembly 44 in order to pivotally connect same
to the frame 22. Like a conventional walking beam, this split
walking beam assembly 44 rotatably supports a pair of wheel axles
46, 48 near its opposing ends, so that two wheels 50, 52 mounted on
these axles are rotatably carried on the walking beam in tandem
positions relative to one another. The wheel axles 46, 48 lie
parallel to the pivot pin or stub shaft 38. However, in the present
invention, instead of the front wheel 50 and rear wheel 52 being
rotatably supported on the same rigid beam, the front wheel 50 is
rotatably carried on the front beam 40 that spans a front half of
the overall walking beam assembly 44, and the rear wheel 52 is
rotatably carried on a rear beam 42 that spans a rear half of the
overall walking beam assembly 44. In the fore-aft longitudinal
direction of the implement, the front end of the front beam is
spaced forwardly of the forward end of the rear beam in the long,
the rearward end of the rear beam is spaced rearwardly of the rear
end of the front beam, and the front and rear beam overlap one
another at the forward end of the rear beam and rear end of the
front beam.
[0093] In each split walking beam assembly 44, the front and rear
beams 40, 42 lie side-by-side with one another a short distance to
the outside of the respective longitudinal frame member 26, and
each feature a respective upright lug 58, 60 projecting upward from
the topside of the beam 40, 42. A respective hydraulic cylinder
actuator 62 of each walking beam assembly 44 has its opposing ends
pivotally coupled to the front and rear top lugs 58, 60 by pivot
pins whose axes lie parallel to the pitch axis P of the
machine.
[0094] The stub shaft or pivot pin 38 passing through the
respective longitudinal frame member 26 also passes through both
the front and rear beams 40, 42 of the respective walking beam
assembly 44 at an area where the two beams 40, 42 overlap in the
longitudinal direction of the machine. The stub shaft or pivot pin
38 thus defines a main walking beam pivot axis W on which the
collective walking beam assembly is pivotal relative to the frame
22, and also defines a coincident second walking beam pivot axis
about which the front and rear beams 40, 42 are pivotable relative
to one another by extension and retraction of the walking beam
actuator 62. This direct coupling together of the front and rear
wheel carrying beams of the walking beam assembly by the same shaft
or pin that couples the walking beam assembly to the frame 22
reduces the number of parts by avoiding an intermediary between the
front and rear beams on which the front and rear wheels are mounted
and sharing the same pivot point for both the relative pivoting
between the front and rear beams and the pivoting of the overall
walking beam assembly relative to the frame.
[0095] When the length of the walking beam actuator 62 is
maintained, an angle .alpha. measured between the front and rear
beams 40, 42 about the axis of the stub shaft or pivot pin 38
walking beam assembly 44 is likewise maintained, and the walking
beam assembly acts as a conventional walking beam in which the
positions of the two wheels 50, 52 are stationary relative to one
another. On the other hand, each side of the frame 22 can be raised
and lowered relative to the ground G by varying the angle .alpha.
between the front and rear beams 40, 42 through extension and
retraction of the respective walking beam actuator 62.
Particularly, if angle .alpha. is measured between the undersides
of the two beams 40, 42, then extending the length of the actuator
62 pushes apart the front and rear lugs 58, 60 at the topsides of
the beams 40, 42, thus forcing the undersides of the two beams
toward one another and reducing the angle .alpha.. This pushes each
of the two wheels 50, 52 downwardly against the ground G on an
arcuate path about the stub shaft or pivot pin 38, thereby lifting
the respective side of the frame 22 upwardly away from the ground
G. Conversely, retracting the length of the actuator 62 draws the
front and rear lugs 58, 60 toward one another, thus drawing the
undersides of the two beams away from one another and increasing
the angle .alpha. in order to lower the respective side of the
frame 22 downwardly toward the ground G. By using the actuator 62
of each walking beam assembly to vary the positions of the two
respective wheels 50, 52 relative to one another about the
respective stub shaft or pivot pin 38, the height of each side of
the frame can thus be varied, and the heights at the opposing sides
of the frame can be set to different values in order to tilt the
frame 22 and the connected box blade assembly 16 about a
longitudinal roll axis R that lies perpendicular to the pivot axes
W of the walking beam assemblies 44.
[0096] In the illustrated embodiment, the front beam 40 of each
split walking beam assembly 44 resides adjacent the outer side of
the respective longitudinal frame member 26, and the rear beam 42
resides opposite the longitudinal frame member 26 to the outside of
the front beam 40. The rear wheel 52 is mounted to the inside of
the rear beam 42, thus riding on the ground in a position trailing
behind the longitudinal frame member 26 in the shadow of same. The
front wheel 50 is mounted to the outside of the front beam 40, i.e.
on the side thereof opposite the frame 22. The front wheel 50
resides nearer to the plane of the respective end wall 20 of the
box blade assembly 16 than the rear wheel, but still a short
distance inboard from this plane. By placing the two wheels of each
walking beam assembly on opposite sides thereof, the wheels are
slightly spaced apart from one another in the transverse direction
of the machine. This way, a rock, bump or other surface disruption
on the ground that is met by one wheel will not necessarily be hit
by the other.
[0097] To demonstrate the functionality of the variable-angle split
walking beams, comparison is made between FIGS. 1 and 2. FIG. 1C
shows the blade in a level orientation parallel to the ground G,
i.e. in a horizontal orientation when all four wheels are resting
on a planar, horizontal ground surface. As shown in FIG. 1B, the
value of angle .alpha. is the same for the two walking beam
assemblies when the blade is level, specifically at a value of
180-degrees in the case of the illustrated scenario. In comparison,
FIG. 2D shows the box blade and frame in a tilted orientation with
the left side thereof lowered into a position closer to the ground
G than the right side. From the perspective views of this tilted
blade orientation in FIGS. 2E and 2F, it can be seen that this
orientation is achieved by using the actuators 62 of the walking
beam assemblies to set the angle .alpha. of the left walking beam
assembly to a greater value than that of the right walking beam
assembly. From the initially level orientation of FIG. 1, this
tilted orientation was achieved by collapsing the actuator 62 of
the left walking beam assembly in order to increase the angle
.alpha. thereof, and extending the actuator of the right walking
beam assembly in order to decrease the angle .alpha. thereof.
[0098] The illustrated embodiment is equipped with a control system
70 for monitoring and automatically controlling the tilt angle of
the frame and blade about the roll axis R. This system 70 is
schematically illustrated in FIG. 3A. A four-way, three-position,
double-solenoid, spring-centered directional valve 72 is used to
control operation of the hydraulic cylinder actuators 62 of both
walking beam assemblies so as to automatically extend one of these
actuators while collapsing the other during any adjustment of the
blade tilt angle. Accordingly, tilting motion is achieved by
simultaneous inverse operation of the two actuators 62 so to raise
one side of the box blade 16 and frame 22 while lowering the other
side thereof. A hydraulic manifold block 74 is cooperatively
attached to the valve 72 for connection of the necessary hydraulic
hoses to the valve. In the illustrated embodiment of the machine,
the valve/manifold assembly 72, 74 is mounted atop the cross-beam
24 of the frame at a slightly off-centre position beside the
mounting lug 32 of the pitch-angle blade 34 actuator, although
other mounting positions can alternatively be employed.
[0099] Using the manifold block 74, a hydraulic supply hose 76 is
coupled between a pressure inlet port of the valve 72 and a
hydraulic pump 78 in order to provide fluid communication between
same. The pump 78 may be part of the implement 10 or part of the
tow vehicle. For example, conventional agricultural tractors have
an onboard hydraulic system for powering hydraulically driven
implements, in which case the existing pump of the tractor can be
used to power the control system of the implement 10 by running the
supply hose 76 along the tongue 12 from the directional control
valve to the fore end of the tongue 12, where the supply hose has a
suitable fitting for coupling to a power hose of the tractor that
is fed by the tractor's hydraulic pump. Via the manifold block 74,
a hydraulic return hose 80 is coupled between a tank return port of
the valve 72 and a hydraulic fluid reservoir 82 in order to provide
fluid communication between same. The valve 72 has two output
ports, each connected to a respective one of the walking beam
actuators 62, via the manifold block 74, by a respective hydraulic
output hose. More specifically, via the manifold block 74, a first
hydraulic output hose 84 is coupled between one output port of the
valve 72 and the extension port 86 of one of the walking beam
actuators 62 (i.e. the port of the actuator on the side of its
piston that drives extension of the actuator's piston rod when
pressurized). A second hydraulic output hose 88 is likewise coupled
between one output port of the valve 72 and the extension port 90
of the other one of the walking beam actuators 62. Finally, a
hydraulic connection hose 92 completes the final hydraulic
connection among the valve and walking beam actuators by connecting
the retractions ports 93 of the two actuators 62 together (i.e. the
port on the side of the piston that drives retraction of the piston
rod further back into the cylinder when pressurized).
[0100] Through these connections, the two walking beam actuators 62
are connected together in series such that extension of one
actuator automatically collapses or retracts the other. The valve
72 is a normally closed valve, in which the spool of the valve 72
is spring biased into a central closed position, blocking off the
pressure port from both of the output ports. A respective solenoid
72a is attached to each end of the spool so that activation of
either solenoid pulls the spool into a respective one of two open
positions, each of which communicates the pressure port with a
respective one of the two output ports and communicates the return
port with the other one of the two output ports. In each open
position, one of the walking beam actuators 62 is extended by
pressurizing the extension side of the cylinder, which drives the
internal piston toward the retraction port of that cylinder,
thereby exhausting hydraulic fluid from the retraction side of that
cylinder into the retraction side of the other hydraulic cylinder
actuator, thereby pressurizing same. The second cylinder is thus
retracted, with the hydraulic fluid on the extension side thereof
being conveyed back to the manifold/valve for exhaust back to the
reservoir tank 82. Accordingly, the two actuators 62 act inversely
to one another, with one actuator being automatically retracted by
the extension of the other.
[0101] An electronic tilt monitoring system 94 features a tilt
sensor mounted somewhere on the box blade assembly 16 or frame 22
and operable to monitor the angular position of same about the roll
axis R. Output signals from the tilt sensor are employed as an
input for automatic control the directional valve 72 based at
partially on these signals. The tilt monitoring system may be
preconfigured or programmed with a target angular position that is
to be maintained by this automated control, for example a tilt
angle of 0-degrees, representing a level blade orientation. In
preferred embodiments, the user can set or select a target angle,
preferably on the fly from the operator cabin of the tow vehicle.
Deviation from the target angular position in either direction
activates the respective one of the solenoids 72a that extends the
actuator 62 on the side of the frame that needs to be raised
relative to the other in order to regain the target tilt angle of
the blade, and holds this open condition of the valve until the
target tilt angle is re-established, at which point the solenoid is
deactivated, at which the spring-centered spool of the valve is
returned to the closed position.
[0102] Directional control valves of the described type are
well-known and commercially available. As an example, a model
D1VW001CNCK4 directional control valve from Parker Hannifin
Corporation of Elyria, Ohio may be employed. The illustrated
embodiment is based on a prototype featuring a model ADO3P012S
parallel circuit valve manifold from Daman Products Company Inc. of
Mishawaka, Ind., which features two tank return ports T, two
pressure ports P, a first output port A, and second output port B,
but has been repurposed for the control system of the present
invention from its original configuration by closing the T port on
one face and the P port on the opposing face with threaded. plugs
73, using the A port as the tank/return port for the reservoir tank
82, using the B port as the pressure port from the pump 78, using
the remaining T port on one face of the manifold block as the
output port to one actuator 62 and using the remaining P port on
the opposing face of the manifold block as the output port to the
other actuator. Use of a specially produced manifold, or
commercially available manifold of appropriate port and passage
configuration, may of course be used in place of the repurposed
Daman manifold.
[0103] U.S. Patent Application Publication 2012/0239258, the
entirety of which is incorporated herein by reference, discloses
and example of a tilt monitoring system that employs a blade tilt
angle sensor in combination with a gyroscope and a blade tip angle
sensor to provide optimal input to a hydraulic blade-tilt control
system. The tilt measurement system of the incorporated reference
may be employed as the blade tilt monitoring system 94 in the
present invention, with the output therefrom controlling operation
of the solenoids 72a of the directional control valve 72 so as to
operate the walking beam actuators 62 of the present invention to
lift and lower the frame and blade, instead of controlling the
blade-tilt actuators 112, 114 of the prior art reference that act
directly between a grader blade and primary frame of a grader
vehicle. Other automated tilt monitoring systems and methods known
in the art may alternatively be used as input to the hydraulic
control system 70 of the present invention. For example, the tilt
monitoring system 94 may use a single tilt sensor alone (i.e.
without the accompanying gyroscope and tip-angle sensor from the
incorporated reference) as the sole measurement source, although
this may be prone to slower response time in control of the blade
and reduced accuracy in the measurements, as outlined in the
incorporated reference.
[0104] Although some embodiments of the present invention employ
the above described automated control of the blade angle, other
embodiments may be manually controlled by the operator of the tow
vehicle, for example by conveying electrical control signals from a
manual lever or other control mechanism in the operator cabin of
the tow vehicle to the directional control valve, for example via
suitable wiring run along the pull tongue 12 of the implement, or
by way of a wireless communication link. The solenoid-operated
valve 72, and the monitoring system 94, may be powered from the
electrical system of the tow vehicle, thus avoiding the need for a
dedicated power supply onboard the implement itself, although such
an option may be employed in other embodiments.
[0105] While the illustrated embodiment features two split walking
beam assemblies 44, another embodiment may feature replacement of
one of the split walking beam assemblies 44 with a conventional
fixed-beam walking assembly, whereby the tilt angle of the blade is
set by adjusting the one split walking beam assembly to set the
height at one side of the frame, without changing the height of the
other side of the frame. While the illustrated embodiment features
a hydraulic control system that automatically operates the two
actuators in inverse of one another, other embodiments are also
contemplated. For example, split walking beam assemblies on
opposing sides of a vehicle or implement (whether a land leveler,
or other machine) may be beneficial even with other control
configurations, for example in a control configuration where the
two walking beam actuators are again operated simultaneously, but
in the same direction, so as to control and overall height of the
vehicle, or in a control configuration in which the two walking
beam actuators are operable independently of one another, for
example to set a desired height at one side of the frame, and a
desired tilt angle of the frame. Split walking beam assemblies can
thus be used for a variety of different vehicle or implement types,
including self-conveying vehicles or implements (as opposed to the
towed implement of the illustrated embodiment), earth-working
implements other than levelers (for example implements of varying
types of ground engagement arrangements, such as gangs, groups or
arrays of ground working members with discrete ground engagement
points instead of a continuous blade running fully from one end of
the ground working arrangement to the other), and vehicles or
implements that lack an earth-working function, but nonetheless
could benefit from height and/or tilt control in an adjustable
angle split walking beam assembly.
[0106] With reference to FIGS. 4 and 5, a conventional rigid-beam
walking axle assembly 100 of the type shown in FIG. 5 can be
substituted for a split walking beam assembly 44 of the present
invention simply by replacing the existing stub shaft or pivot pin
102 of the existing walking beam 100 with a longer stub shaft or
pivot pin 38 of sufficient length to pass through both beams of the
new split walking beam assembly 44, which is thus mounted on this
new stub shaft or pivot pin 38. Walking beams on opposing sides of
the frame of the previously-conventional vehicle can thus be
replaced in this manner. The hydraulic actuators 62 of the split
walking beams then be connected to an existing hydraulic system of
the vehicle or implement, if so equipped, or a hydraulic system can
be added to the vehicle or implement if it previously lacked a
suitable hydraulic power system for the split walking beams.
Examples of vehicles in which an adjustable angle split walking
beam axle may be useful include rock trucks, semis, mining
equipment, military equipment such as troop transporters, or
possibly even for idler wheels of track-equipped vehicles.
[0107] Since various modifications can be made in my invention as
herein above described, and many apparently widely different
embodiments of same made within the scope of the claims without
departure from such scope, it is intended that all matter contained
in the accompanying specification shall be interpreted as
illustrative only and not in a limiting sense.
* * * * *