U.S. patent application number 10/932134 was filed with the patent office on 2006-03-02 for vertical outrigger leg.
Invention is credited to Martin G. Mayer.
Application Number | 20060043718 10/932134 |
Document ID | / |
Family ID | 35106663 |
Filed Date | 2006-03-02 |
United States Patent
Application |
20060043718 |
Kind Code |
A1 |
Mayer; Martin G. |
March 2, 2006 |
Vertical outrigger leg
Abstract
An outrigger assembly for the support and stabilization of a
mobile work machine, such as a vehicle-mounted telescopic belt
conveyor, while the machine is operating. The outrigger assembly
includes a vertical outrigger leg assembly. The vertical outrigger
leg assembly is attached to the end of a horizontally extending
member and includes multiple telescopically extendable sections
that extend until a support pad is in contact with the work
surface, then raise the mobile work machine off of the ground into
a stabilized position. The multiple leg sections allow for
increased vertical lifting distance, thus improving stability on
uneven work surfaces, and allow the outrigger assembly to be used
on larger machines.
Inventors: |
Mayer; Martin G.;
(Reutlingen, DE) |
Correspondence
Address: |
Joseph D. Kuborn;ANDRUS, SCEALES, STARKE & SAWALL, LLP
Suite 1100
100 East Wisconsin Avenue
Milwaukee
WI
53202-4178
US
|
Family ID: |
35106663 |
Appl. No.: |
10/932134 |
Filed: |
September 1, 2004 |
Current U.S.
Class: |
280/763.1 |
Current CPC
Class: |
B66C 23/80 20130101;
E02F 9/085 20130101 |
Class at
Publication: |
280/763.1 |
International
Class: |
E02F 3/00 20060101
E02F003/00 |
Claims
1. An outrigger assembly for stabilizing a mobile work machine,
comprising: an outrigger leg housing having an open interior; a
hydraulic cylinder having an outer wall and an open interior, the
hydraulic cylinder being operatively positioned within the
outrigger leg housing and movable within the outrigger leg housing
between a retracted position and an extended position; a leg member
telescopically positioned within the hydraulic cylinder, the leg
member being moveable between a retracted position in which the leg
member is contained within the hydraulic cylinder and an extended
position in which the leg member extends from the hydraulic
cylinder, and wherein the hydraulic cylinder and the leg member are
each movable from the retracted position to the extended position
and from the extended position to the retracted position by
hydraulic pressure.
2. The outrigger assembly of claim 1 wherein the outrigger leg
housing, the hydraulic cylinder, and the leg member are centered on
a common axis.
3. The outrigger assembly of claim 2 wherein the common axis is a
vertical axis.
4. The outrigger assembly of claim 3 wherein the movement of the
hydraulic cylinder and leg member is along the vertical axis.
5. The outrigger assembly of claim 1 wherein the hydraulic cylinder
forms a seal between its outer wall and the open interior of the
outrigger leg housing and a seal between its open interior and the
leg member.
6. (canceled)
7. The outrigger assembly of claim 1 wherein the outrigger leg
housing includes a first hydraulic inlet and a second hydraulic
inlet.
8. The outrigger assembly of claim 7 wherein hydraulic pressure is
applied to the first hydraulic inlet to move both the hydraulic
cylinder and the leg member from the retracted position to the
extended position.
9. The outrigger assembly of claim 8 wherein hydraulic pressure is
applied to the second hydraulic inlet to move both the hydraulic
cylinder and the leg member from the extended position to the
retracted position.
10. The outrigger assembly of claim 1 wherein the outer wall of the
hydraulic cylinder includes a hydraulic passage to communicate the
hydraulic fluid to the leg member.
11. The outrigger assembly of claim 1 further comprising a support
pad mounted to a lower end of the leg member.
12. The outrigger assembly of claim 1 wherein the hydraulic
cylinder and the leg member are independently movable between their
respective extended positions and retracted positions.
13. The outrigger assembly of claim 1 further comprising: a
stationary support housing mountable to the work machine; an inner
housing telescopically positioned within the stationary support
housing, wherein the inner housing is connected to and supports the
outrigger leg housing; and a drive cylinder operatively positioned
between the stationary support housing and the inner housing, the
drive cylinder being operable to move the inner housing between a
retracted position in which the inner housing is positioned within
the stationary support housing and an extended position in which
the inner housing extends from the stationary support housing.
14. The outrigger assembly of claim 13 wherein the outrigger
assembly is connected to a distal end of the inner housing.
15. The outrigger assembly of claim 13 wherein the drive cylinder,
the hydraulic cylinder, and the leg member are independently
movable such that the hydraulic cylinder and the leg member can be
extended while the inner housing is positioned at any location
between its extended and retracted positions.
16. An outrigger assembly for stabilizing a mobile work machine,
comprising: an outrigger leg housing having an open interior; a
hydraulic cylinder having an outer wall and an open interior, the
hydraulic cylinder being operatively positioned within the
outrigger leg housing and movable within the outrigger leg housing
between a retracted position and an extended position; a leg member
telescopically positioned within the hydraulic cylinder, the leg
member being movable between a retracted position in which the leg
member is contained within the hydraulic cylinder and an extended
position in which the leg member extends from the hydraulic
cylinder; a first hydraulic inlet located in the outrigger leg
housing; a second hydraulic inlet located in the outrigger leg
housing; wherein pressurized hydraulic fluid is applied to the
first hydraulic inlet to move the hydraulic cylinder and the leg
member from their retracted positions to their extended positions;
and wherein pressurized hydraulic fluid is applied to the second
hydraulic inlet to move the hydraulic cylinder and the leg member
from their extended positions to their retracted positions.
17. The outrigger assembly of claim 16 wherein the outrigger
assembly is perpendicularly connected to a horizontally oriented
inner housing.
18. The outrigger assembly of claim 17 wherein the inner housing is
positioned within a stationary support housing connected to the
mobile work machine.
19. The outrigger assembly of claim 18 wherein the inner housing is
extendably connected to the stationary support housing by a drive
cylinder.
20. The outrigger assembly of claim 16 wherein the hydraulic
cylinder forms a seal between its outer wall and the outer wall of
the outrigger leg housing and a seal between its outer wall and the
leg member.
21. (canceled)
22. An outrigger assembly for stabilizing a mobile work machine,
comprising: a vertically oriented outrigger leg housing having an
outer wall, a first and second inlet, and an open interior; a
vertically oriented hydraulic cylinder telescopically positioned
within the outrigger leg housing having an outer wall and an open
interior; a vertically oriented leg member with a support pad
attached to a lower end of the leg member, wherein the leg member
is telescopically positioned within the hydraulic cylinder, the leg
member being moveable from a retracted position to an extended
position; a stationary support housing attached to the mobile work
machine; and an inner housing connected within the stationary
support housing, wherein the inner housing is extendable by a drive
cylinder utilizing hydraulic pressure; and wherein the leg assembly
is movable from a retracted position to an extended position by
pressurized hydraulic fluid supplied through the first inlet and
the leg assembly is movable from an extended position to a
retracted position by pressurized hydraulic fluid supplied through
the second inlet; and wherein a plurality of outrigger leg
assemblies are mounted to the mobile work machine and the drive
cylinders and leg assemblies are independently movable.
23. The outrigger assembly of claim 16 further comprising: a
hydraulic passage located within the outer wall of the hydraulic
cylinder; an open interior within the outrigger leg housing; and an
open interior within the hydraulic cylinder; wherein the open
interior of the outrigger leg housing is in fluid communication
with the open interior of the hydraulic cylinder through the
hydraulic passage.
24. The outrigger assembly of claim 23 wherein pressurized
hydraulic fluid is supplied through the first inlet to the open
interior of the outrigger leg housing to move the hydraulic
cylinder and leg member from a retracted position to an extended
position; and wherein pressurized hydraulic fluid is supplied
through the second inlet to the hydraulic passage to move the
hydraulic cylinder and leg member from an extended position to a
retracted position.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an outrigger assembly for
stabilizing a mobile work machine. More specifically, the present
invention is an outrigger assembly for stabilizing a
self-propelled, vehicle-mounted conveyor system used to place
concrete or other materials in a desired location where the
vertical movement of the outrigger leg is actuated by utilizing
multiple cylinders to direct the multiple telescoping leg
sections.
[0002] Vehicle-mounted, extendable material placement systems have
been in use for some time and are the subject of numerous prior
patents. In such vehicles, a telescopic or sectional-unfolding boom
extends from a rotating turret attached to the vehicle. The
substantial amount of weight extending from the vehicle chassis
necessitates the use of outriggers to stabilize the vehicle and
prevent the vehicle from tilting or overturning. Extendable
material placement systems are most typically utilized during the
construction of new buildings. This often requires placement and
operation of the vehicle on rough and uneven ground. The use of
outriggers increases the footprint of the extendable material
placement system thereby making it more stable. For the outrigger
legs to properly serve their function, the outrigger legs must have
sufficient clearance to fully extend out over the uneven
ground.
[0003] Vehicle-mounted, extendable concrete conveyor systems, such
as shown in U.S. Pat. No. 4,624,357 has been in use for some time.
In such vehicles, a discharge conveyor assembly includes a
telescoping boom having its base pivotally mounted to the torque
tube of the vehicle chassis. The substantial amount of weight
extending from the vehicle chassis necessitates the use of
outriggers to stabilize the vehicle and prevent the vehicle from
tilting or overturning.
[0004] The most common type of outrigger system includes a
plurality of telescoping legs that can each be extended from a
stationary housing fixed to the vehicle. An example of this type of
outrigger is shown in U.S. Pat. No. 4,949,808. This common
outrigger assembly employs multiple horizontal telescoping members.
Because both the discharge conveyor assembly and the infeed
conveyor assembly are rotatable about a turnable assembly mounted
to the vehicle chassis, multiple sections must be used to cover the
necessary distance in order to create an outrigger footprint that
will achieve the desired stability. In this common type of
outrigger design, both the horizontal and vertical travel over the
outrigger leg is achieved by a single hydraulic cylinder.
[0005] A vehicle-mounted conveyor system presents unique problems
in the design of the outrigger assembly. The outrigger assembly
must be mounted to the vehicle in a way such that the conveyor
assemblies can rotate about the vehicle without contacting the
outrigger assemblies. However, due to the length of the extendable
boom contained on the discharge conveyor, a significant amount of
weight positioned away from the center of gravity of the vehicle
must be supported by the vehicle chassis. Therefore, in addition to
being designed to avoid contact with the conveyor assemblies, the
outrigger assemblies must extend a sufficient distance from the
vehicle chassis in order to provide the required stability for the
vehicle. The combination of these two requirements dictates that
the height the outriggers at their furthest point from the chassis
will be limited. Because of this height limit, a single-stage
vertical leg will be very limited in its capability to elevate the
entire machine into a stable condition. Additionally, uneven
terrain on the job site prevents a stable set up unless the
vertical legs were of a telescoping design of multiple cylinders
used to drive the multiple leg sections.
[0006] It is an object of the present invention to provide an
outrigger assembly for use with a vehicle-mounted conveyor system
to provide the required stability of the vehicle while preventing
possible contact between the main discharge conveyor assembly and
the individual outrigger. Further, it is an object of the invention
to provide a vertical outrigger leg for use on rough, unmade, or
uneven ground by extending the frame of the machine laterally and
lifting the machine vertically. It is another object of the present
invention to provide a plurality of outrigger assemblies in which
each outrigger assembly is contained within the overall vehicle
width when in its completely retracted position. Additionally, it
is an object of the present invention to provide an outrigger
assembly that includes a multi-section, vertically telescoping
assembly to increase the vertical distance the outrigger leg
assembly can travel in order to make solid contact with the ground
to establish the desired stability.
SUMMARY OF THE INVENTION
[0007] The present invention is an outrigger assembly for use with
a mobile work machine, such as a vehicle-mounted telescopic belt
conveyor, to stabilize the machine when the machine is operating.
The work machine includes a plurality of the individual outrigger
assembly to provide multiple points of stabilization for the
vehicle when the extendable conveyor is in use.
[0008] Each outrigger assembly for stabilizing a mobile work
machine includes an outer support housing having an open interior,
a hydraulic cylinder movable within the outer support housing and
having an open interior, and a leg member telescopically positioned
within the hydraulic cylinder. The hydraulic cylinder is
operatively positioned within the outer support housing and moves
between a retracted position within the outer support housing and
an extended position. The leg member also moves from a retracted
position in which the leg member is contained within the hydraulic
cylinder to an extended position. The outer support housing, the
hydraulic cylinder, and the leg member are all centered along a
common vertical axis and the hydraulic cylinder and leg member move
along this vertical axis.
[0009] The hydraulic cylinder and the leg member of the outrigger
assembly are each movable by hydraulic pressure supplied through a
first hydraulic inlet for movement from the retracted to the
extended position and a second hydraulic inlet for movement from
the extended to the retracted position. The hydraulic fluid is able
to pass from the hydraulic cylinder to the leg member by a
hydraulic passage formed in the wall of the hydraulic cylinder.
[0010] The outrigger assembly additionally includes a stationary
support housing that is mounted to the concrete placing machine, an
inner housing that is telescopically positioned within the
stationary support housing, and a drive cylinder, that is operably
positioned between the support housing and the inner housing. The
drive cylinder is operable to move the inner housing between a
retracted position in which the inner housing is positioned within
the support housing and an extended position in which the inner
housing extends from the stationary support housing. The outrigger
assembly is vertically oriented and connected to the extendable end
of the inner housing. The drive cylinder, hydraulic cylinder, and
leg member are all independently operable such that the hydraulic
cylinder and leg cylinder, or both, can be extended while the inner
housing is in either the retracted position or the extended
position.
[0011] The outrigger assembly of the invention includes a
vertically oriented outrigger leg housing having an open interior,
a vertically oriented hydraulic cylinder having an open interior
and being operably positioned within the support housing, a
vertically oriented leg member that is telescopically positioned
within the hydraulic cylinder, and an inner housing that is
extendably movable relative to the mobile work machine. The
outrigger leg housing is aligned along the same vertical axis as
the hydraulic cylinder and the leg member and is connected to the
distal end of the inner housing.
[0012] In a preferred embodiment of the invention, the inner
housing extends from the mobile work machine until the proper
extended width is achieved. Both the hydraulic cylinder and the leg
member may be extended vertically by use of hydraulic pressure to a
ground-engaging position with the support pad mounted at the lower
end of the leg member contacting the ground. Further extension of
the hydraulic cylinder and the leg member results in the lifting of
the vehicle body off the ground to further stabilize the machine
during operation. An advantage of the outrigger assembly of the
present invention is that it affords greater stabilization for the
mobile work machine because of the expanded outrigger leg
horizontal reach positions, and increased vertical lift whereby the
mobile work machine may be stabilized more effectively in a greater
range of ground types and slopes.
[0013] The preferred embodiment of the invention also calls for the
implementation of a plurality of outrigger legs attached to the
mobile work machine.
[0014] Various other features, objects, and advantages of the
invention will be made apparent from the following description
taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The drawings illustrate the best mode presently contemplated
of carrying out the invention.
[0016] In the drawings:
[0017] FIG. 1 is a side elevation view of a self-propelled vehicle
including a vehicle-mounted conveyor system and a plurality of
outrigger assemblies constructed in accordance with the present
invention;
[0018] FIG. 2 is a top plan view of the vehicle illustrated with
the outrigger assemblies of the present invention in their fully
extended, ground-engaging position;
[0019] FIG. 3 is a rear view of the vehicle with the rear outrigger
assemblies in their fully retracted position;
[0020] FIG. 4 is a rear view similar to FIG. 3 illustrating the
outrigger assemblies in their fully extended position;
[0021] FIG. 5 is a section view showing an outrigger assembly of
the present invention in its fully retracted position;
[0022] FIG. 6 is a section view of an outrigger leg assembly of the
present invention in which the leg member is extended and the
hydraulic cylinder is in the retracted position;
[0023] FIG. 7 is a cut away view of an outrigger leg assembly of
the present invention in the fully extended, ground-engaging
position with both the leg member extended and the hydraulic
cylinder extended.
DETAILED DESCRIPTION OF THE INVENTION
[0024] A mobile work machine, such as a self-propelled vehicle 20
including a vehicle-mounted conveyor system 22 for transporting an
aggregate material such as concrete is best shown in FIGS. 1 and 2.
The vehicle 20 includes a conventional cab 24 and a torque tube 26.
The vehicle 20 is of a size such that it does not exceed the legal
dimensional limits for over the highway travel.
[0025] The conveyor system 22 includes an in-feed conveyor assembly
28 that receives the supply of aggregate material, such as
concrete, from a supply source 30 and transports the material
upward along a moving in-feed conveyor belt. The in-feed conveyor
assembly 28 is rotatable about the vehicle 20 such that the in-feed
conveyor assembly 28 can receive the supply of material at various
locations around the vehicle 20.
[0026] The conveyor system 22 includes a main turret 32 that is
rotatably mounted to the torque tube 26 of the vehicle 20. A
discharge conveyor assembly 34 is pivotally mounted to the main
turret 32 about a horizontal pivot axis and also rotates along with
the main turret 32. Specifically, the discharge conveyor assembly
34 includes a telescoping boom 36 having its base end mounted in a
cantilever manner to the main turret 32. The discharge end 38 of
the discharge conveyor assembly 34 is extendable away from the main
turret 32 to control placement of the conveyed aggregate from the
discharge end 38.
[0027] As can be seen in FIG. 2, the vehicle 20 includes a pair of
front outrigger assemblies 40a and 40b, and a pair of rear
outrigger assemblies 42a and 42b. Each of the outrigger assemblies
extends from the torque tube 26 in a direction transverse to the
longitudinal axis of the vehicle 20. The outrigger assemblies are
operable to elevate the vehicle 20 above the ground and stabilize
the vehicle to allow the discharge conveyor assembly 34 to be
extended in the manner shown in FIG. 1. In general, each of the
outrigger assemblies 40a, 40b, 42a and 42b includes identical
operating components and function in an identical manner such that
the single description of the outrigger assembly below is
applicable to each of the outrigger assemblies. The four individual
outrigger assemblies shown in FIGS. 1 and 2 provide the required
stabilization for the vehicle 20 during operation of the
telescoping boom 36.
[0028] FIG. 3 illustrates the rear outrigger assembly 42b in its
fully retracted position. The outrigger assembly 42b includes a
stationary support housing 44 that is securely mounted to the
vehicle chassis and is positioned behind the rear wheels 47 of the
vehicle 20.
[0029] The rear outrigger assembly 42b is shown in FIG. 4 in its
fully extended, ground-engaging position. When in the fully
extended position, the movable inner housing 46 extends from the
stationary support housing 44. An outrigger leg assembly 48 is
securely attached to the outermost end of the inner housing 46. The
outrigger leg assembly 48 includes an outrigger leg housing 54, a
hydraulic cylinder 52, and a leg member 50, all of which are
vertically aligned along a common central axis 118. The leg member
50 is telescopically movable into and out of the hydraulic cylinder
52 which, in turn, is telescopically movable into and out of the
outrigger leg housing 54. A support pad 56 is mounted to the leg
member 50. The support pad 56 contacts the ground 60 when the
outrigger assembly 42b is in its fully extended, ground-engaging
position. In addition to the rear outrigger assembly 42b, FIG. 4
also illustrates the rear outrigger assembly 42a in its fully
extended position. The combination of the pair of fully extended
rear outrigger assembles 42a and 42b elevate the rear wheels 47 of
the vehicle 20 above the ground 60, as can be clearly seen in FIG.
4.
[0030] FIGS. 5, 6 and 7 illustrate the detailed construction of the
rear outrigger assembly 42b, although the following description is
equally applicable to each of the outrigger assemblies. As
previously discussed, the outrigger assembly 42b includes the
stationary support housing 44 securely connected to the chassis of
the vehicle 20. The support housing 44 is formed from a generally
rectangular outer shell 45 constructed from a metallic material,
such as steel. In the preferred embodiment of the invention, the
support housing 44 has an overall length of approximately 98
inches, which is approximately equal to the width of the vehicle
chassis.
[0031] As can be seen in FIG. 5, the outer shell 45 of the support
housing 44 defines a generally open interior 64 that extends
between a closed back end 66 and open-front end 68. The front end
68 of the support housing 44 includes a reinforcing ridge 70
extending upward from the outer shell 45. The reinforcing ridge 70
contacts a corresponding reinforcing ridge 72 formed on an outer
shell 74 that defines the inner housing 46.
[0032] As can be seen in the combined views of FIGS. 2 and 5, the
inner housing 46 is also generally rectangular and defines an open
interior 76 extending between an open back-end 78 and an open-front
end 80. As can be understood in FIGS. 2, 3 and 4, the inner housing
46 is extendable into and out of the open interior 64 defined by
the support housing 44. Specifically, the inner housing 46 is
movable between a retracted position in which nearly the entire
inner housing 46 is contained within the support housing 44, and an
extended position in which a substantial portion of the inner
housing 46 extends from the support housing 44, as shown in FIG.
4.
[0033] In the preferred embodiment of the invention, the means for
moving the inner housing 46 into and out of the support housing 44
is a first drive cylinder 82. The first drive cylinder 82 is a
fluid-actuated cylinder having a cylinder body 84 and an extendable
cylinder rod 86. The cylinder body 84 is contained in the open
interior 76 defined by the outer shell 74 of the inner housing 46
and extends between a first end 88 and a second end 89. The second
end 89 of the cylinder body 84 is securely connected by a pivot pin
91 to the inner surface 90 of a support plate 93 at the closed back
end 66 of the stationary support housing 44. Specifically, the
pivot pin 91 passes through a mounting block 92 to secure the
second end 89 of the cylinder body 84 to the inner surface 90. In
this manner, the cylinder body 84 is securely attached to the
stationary support housing 44.
[0034] The first end 88 of cylinder rod 86 is securely attached to
saddle 94 by a mounting pin 96. The saddle 94 is securely attached
to the inner surface 95 of the mounting beam 49, which is secured
to the inner wall of the inner housing 46. When the first drive
cylinder 82 is actuated, the cylinder rod 86 is forced out of the
cylinder body 84, causing the inner housing 46 secured to the first
end 88 of the cylinder body 84 to move outward. The inner housing
46 continues to move outward relative to the stationary support
housing 44 until the cylinder rod 86 is completely extended. When
the cylinder rod 86 is fully extended, the inner housing 46 is in
its completely extended position.
[0035] In the preferred embodiment of the invention, the first
drive cylinder 82 is a two-directional fluid-actuated cylinder such
that the first drive cylinder 82 can be operated in a reverse
direction to retract the cylinder rod 86 into the cylinder body 84
and move the inner housing 46 from the fully extended position to
the retracted position.
[0036] In the preferred embodiment of the invention, the first
drive cylinder 82 is positioned inside the outer shell 74 of the
inner housing 46. Thus, when the inner housing 46 is in its
extended position, the first drive cylinder 82 is concealed within
the inner housing 46, as can be seen in FIG. 4.
[0037] The outrigger leg assembly 48 is perpendicularly connected
to the mounting beam 49, which is securely attached to the inner
surface of the inner housing 46. The outrigger leg assembly 48 is
vertically oriented and is shown in its completely retracted
position in FIG. 5 and in its extended position in FIG. 7. The
outrigger leg assembly 48, and specifically the hydraulic cylinder
52 and leg member 50, is vertically movable along the common
vertical axis 118 from the retracted position (FIG. 5) to the
extended ground-engaging position (FIG. 7) in which the support pad
56 contacts the ground 60. The support pad 56 is connected to a
first end 50a of leg member 50. The second end 50b of the leg
member 50 is movably positioned within hydraulic cylinder 52.
[0038] As shown in FIG. 7, the hydraulic cylinder 52 has a first
end 52a and a second end 52b and is movably positioned within
outrigger leg housing 54. The hydraulic cylinder 52 is further
comprised of an outer wall 52c having a hydraulic passage 102
disposed within the outer wall 52c and an open interior 98
surrounded by the outer wall 52c.
[0039] The outrigger leg housing 54 generally includes a bottom end
54a, a top end 54b, and an outer wall 54c. The outer wall 54c
defines an open interior 100. The outer wall 54c includes a first
hydraulic inlet 58 and second hydraulic inlet 60 connected to the
outrigger leg housing 54 at top end 54b and bottom end 54a
respectively. A first hydraulic channel 59 passes through outer
wall 54c connecting the first hydraulic inlet 58 to the open
interior 100 and a second hydraulic channel 61 connects second
hydraulic inlet 60 to a first hydraulic cavity 104. As shown in
FIG. 6, the first hydraulic cavity 104 is defined as the space
between the second end 52b of the hydraulic cylinder and the bottom
end of the outrigger leg housing 54a.
[0040] In the preferred embodiment of the invention, the means for
moving the leg assembly 48 from its retracted position depicted in
FIG. 5 to its extended position depicted in FIG. 7 is hydraulic
pressure. Starting in the retracted position depicted in FIG. 5,
hydraulic fluid is pumped through first hydraulic inlet 58 and
first hydraulic channel 59 of leg assembly 48 into the open
interior 100. As the pressure within the open interior 100
increases, the pressure is displaced against the second or top ends
of the leg member 50b and the hydraulic cylinder 52b. A first
cylinder seal member 108 and a second cylinder seal member 112
allow the hydraulic pressure in the open interior 100 to force the
hydraulic cylinder 52 to telescope out of the outrigger leg housing
54 and the leg member 50 to telescope out of the hydraulic cylinder
52.
[0041] As shown in FIG. 6, the leg member 50 continues to extend
until the first end 52a of the hydraulic cylinder 52 comes in
contact with the second end 50b of the leg member 50. As shown in
FIG. 7, the hydraulic cylinder 52 also continues to extend until
the second end 52b of the hydraulic cylinder comes in contact with
the bottom end 54a of the outrigger leg housing 54 and the
outrigger leg assembly is in its fully extended position. The
hydraulic pressure is maintained in the open interior 100 while the
outrigger leg 48 is extended by the first cylinder seal 108 located
between the outer surface of the second end 52b of the hydraulic
cylinder and the inner surface of the outrigger leg housing outer
wall 54c. A cylinder seal 112 is positioned between the outer
surface of the leg member second end 50b and the inner surface of
the hydraulic cylinder outer wall 52c.
[0042] In the preferred embodiment of the invention, the leg
assembly 48 also moves from its fully extended position depicted in
FIG. 7 to its retracted position depicted in FIG. 5 by means of
hydraulic pressure. To effect such movement, hydraulic fluid is
pumped into the second hydraulic inlet 60 and through the outrigger
leg housing outer wall 54c by means of the second hydraulic channel
61. The supply of hydraulic fluid is received in the first
hydraulic cavity 104, as shown in FIG. 7. As the hydraulic pressure
within the first hydraulic cavity 104 increases, the pressure is
exerted on the hydraulic cylinder second end 52b, forcing the
hydraulic cylinder 52 to retract into the open interior 100 of the
outrigger leg housing 54. As the hydraulic cylinder 52 retracts
into outrigger leg housing 54, the first hydraulic cavity 104
increases in volume. Hydraulic pressure is maintained in the first
hydraulic cavity 104 due to the first cylinder seal 108 and a
second cylinder seal 110. The second cylinder seal 110 is between
the interior surface of the outrigger leg housing bottom 54a and
the outer surface of the hydraulic cylinder outer wall 52c. As the
hydraulic cylinder 52 is retracted, hydraulic fluid is allowed to
flow out of the open interior 100 through the cavity 59 and the
inlet 58.
[0043] When the hydraulic cylinder 52 sufficiently retracts into
the open interior 100 of the outrigger leg housing 54, the inflow
end 116 of hydraulic passage 102 connects to the first hydraulic
cavity 104 and allows hydraulic fluid to flow from the first
hydraulic cavity 104 to a second hydraulic cavity 106 located
between the bottom surface of the leg member second end 50b and the
top surface of the hydraulic cylinder first end, as shown in FIG.
6. As the hydraulic pressure within the second hydraulic cavity 106
increases, the leg member 50 is retracted into the open interior 98
of the hydraulic cylinder 52. As the hydraulic pressure within the
first hydraulic cavity 104 and the second hydraulic cavity 106
continues to increase, the hydraulic cylinder 52 and the leg member
50 are further retracted into the open interiors 100 and 98. As
discussed, the hydraulic fluid that had been residing in the open
interiors 100 and 98 is forced back through the first hydraulic
channel 59 and the first hydraulic inlet 58.
[0044] Although the first drive cylinder 82, the outrigger leg
housing 54 and the hydraulic cylinder 52 are shown and described as
being fluid-driven cylinders, it is contemplated by the inventors
that each of these cylinders could be replaced by an equivalent
means for driving the inner housing 46, the hydraulic cylinder 52,
and the like member 50 between their extended and retracted
positions. For example, it is contemplated by the inventors that a
rotating screw drive mechanism, air cylinder, or other equivalent
structure could replace the fluid-driven cylinders shown.
[0045] In the preferred embodiment of the invention the outrigger
assemblies 40a, 40b, 42a, and 42b operate as discussed above
utilizing a single source of hydraulic pressure. This results in
optimal operation of the outrigger assembly during use upon ground
of a varying elevation. When the outrigger assemblies 40a, 40b,
42a, and 42b begin to extend from their fully retracted position,
hydraulic pressure will be supplied to each assembly evenly and the
leg members 50 and hydraulic cylinders 52 will extend evenly.
However, once a support pad 56 of one of the outrigger leg
assemblies 40a, 40b, 42a, and 42b contacts the ground, it will
require less pressure to extend the other outrigger leg assemblies.
The outrigger leg assembly in contact with the ground will stop
extending while the other outrigger leg assemblies continue to
extend until all of the support pads are in contact with the
ground. The pressure required to extend each of the outrigger leg
assemblies will then be even and the mobile work machine 20 will
rise and be supported in a level fashion despite the uneven
extension of each of the outrigger leg assemblies. This maintains
the mobile work machine's center of gravity between the outrigger
leg assemblies, thus ensuring the stability of the mobile work
machine 20 in its raised position, despite the ground underneath
each outrigger leg assembly being of a different elevation.
[0046] Various alternatives and embodiments are contemplated as
being within the scope of the following claims particularly
pointing out and distinctly claiming the subject matter regard as
the invention.
[0047] While the invention has been described with reference to a
preferred embodiment, those skilled in the art will appreciate that
certain substitutions, alterations and omissions may be made
without departing from the spirit thereof. Accordingly, the
foregoing description is meant to be exemplary only and should not
be deemed limitative on the scope of the invention set forth with
the following claims.
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