U.S. patent application number 10/680551 was filed with the patent office on 2004-07-01 for lightweight portable stage.
Invention is credited to Quam, Grant S., Wiese, Steven E..
Application Number | 20040123529 10/680551 |
Document ID | / |
Family ID | 32659210 |
Filed Date | 2004-07-01 |
United States Patent
Application |
20040123529 |
Kind Code |
A1 |
Wiese, Steven E. ; et
al. |
July 1, 2004 |
Lightweight portable stage
Abstract
A self-contained mobile stage system for outdoor performances
that is transportable with a light tow vehicle, and with features
for easy deployment by one person alone. The mobile stage trailer
includes a chassis having a pair of decks, including an upper deck
and a lower deck vertically spaced apart from the upper deck. A
retractable hitch assembly is coupled with the chassis for coupling
the trailer with the tow vehicle. A wing deck is coupled with the
chassis at each lateral edge. The wing decks are selectively
positionable in a first favored position proximate the upper deck
of the chassis portion so that the upper deck and the wing decks
together present an upwardly directed surface for performances. The
wing decks are further selectively positionable in a second favored
position for towing wherein the system presents a system width
dimension generally equal to the width of the chassis alone.
Inventors: |
Wiese, Steven E.; (Owatonna,
MN) ; Quam, Grant S.; (Owatonna, MN) |
Correspondence
Address: |
PATTERSON, THUENTE, SKAAR & CHRISTENSEN, P.A.
4800 IDS CENTER
80 SOUTH 8TH STREET
MINNEAPOLIS
MN
55402-2100
US
|
Family ID: |
32659210 |
Appl. No.: |
10/680551 |
Filed: |
October 7, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60416954 |
Oct 7, 2002 |
|
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|
Current U.S.
Class: |
52/6 ;
52/79.1 |
Current CPC
Class: |
E04H 3/28 20130101 |
Class at
Publication: |
052/006 ;
052/079.1 |
International
Class: |
E04H 003/10; E04H
001/00 |
Claims
What is claimed is:
1. A portable stage system adapted for towing by a tow vehicle, the
system comprising: a chassis portion having a pair of ground
engaging wheels and a pair of vertically spaced apart decks
including a generally planar upper deck and a lower deck, the pair
of decks defining a cargo space therebetween for storing and
transporting cargo, the chassis portion presenting a chassis width
dimension; and at least one generally planar wing deck operably
coupled to the chassis portion, the at least one wing deck being
selectively shiftable between a first favored position adjacent and
substantially coplanar with the upper deck of the chassis portion
and a second favored position for towing wherein the system
presents a towing width dimension, the towing width dimension being
equal to or less than the chassis width dimension.
2. The portable stage system of claim 1, further comprising at
least one selectively deployable accessory item.
3. The portable stage system of claim 2, wherein the at least one
selectively deployable accessory item is selected from the group
consisting of a guardrail, a railing, a stair, a canopy, and a
modular stage component.
4. The portable stage system of claim 2, wherein the at least one
selectively deployable accessory item is adapted to be stowable in
said cargo space.
5. The portable stage system of claim 1, wherein the lower deck has
a plurality of tie-down structures for securing cargo.
6. The portable stage system of claim 1, further comprising a
plurality of closure panels for enclosing the cargo space.
7. The portable stage system of claim 1, further comprising a hitch
on the chassis portion for coupling the stage system to the tow
vehicle.
8. The portable stage system of claim 7, wherein the hitch portion
is selectively operably positionable in a first extended position
wherein the hitch portion is projecting forwardly from the chassis
portion and in a second retracted position wherein substantially
all of the hitch portion is disposed under the lower deck of the
chassis portion.
9. The portable stage system of claim 1, wherein the chassis
portion has a plurality of selectively operably positionable
leveling jacks for supporting and leveling said stage.
10. The portable stage system of claim 1, wherein the chassis
portion has a plurality of leveling indicators for determining
whether said stage is disposed in a level condition.
11. The portable stage system of claim 1, wherein the at least one
wing deck has a plurality of selectively positionable support legs
operably attached thereto.
12. The portable stage system of claim 11, wherein each of the
plurality of support legs includes means for adjusting the length
of the support leg.
13. The portable stage system of claim 1, further comprising means
for attaching at least one modular stage component to the
system.
14. The portable stage system of claim 1, wherein the stage
includes a second wing deck operably coupled to the chassis
portion, the second wing deck being selectively shiftable between a
first favored position adjacent and substantially coplanar with the
upper deck of the chassis portion and a second favored position for
towing wherein the system presents a towing width dimension, the
towing width dimension being equal or less than the chassis width
dimension.
15. The portable stage system of claim 1, wherein the upper deck
and the at least one wing deck are at least partially covered with
an anti-slip material.
16. A mobile stage trailer adapted for towing by a tow vehicle, the
trailer comprising: a chassis having a pair of vertically spaced
apart decks including an upper deck and a lower deck, the chassis
presenting a chassis width dimension; a hitch assembly operably
coupled with the chassis for selectively coupling the trailer with
a tow vehicle; at least two ground engaging wheels operably coupled
with the chassis; and a pair of wing decks operably coupled with
the chassis, each wing deck selectively positionable in a first
favored position adjacent the upper deck of the chassis portion
wherein the upper deck and the pair of wing decks together present
an upwardly directed surface for performances, each wing deck being
further selectively positionable in a second favored position for
towing wherein the system presents a towing width dimension, the
towing width dimension being equal to or less than the chassis
width dimension.
17. The mobile stage trailer of claim 16, wherein the hitch
assembly is selectively operably positionable in a first extended
position wherein the hitch assembly is projecting forwardly from
the chassis and in a second retracted position wherein
substantially all of the hitch assembly is disposed under the lower
deck of the chassis.
18. The mobile stage trailer of claim 16, further comprising at
least one accessory item selected from the group consisting of a
guardrail, a railing, a stair, a canopy, and a modular stage
component.
19. The mobile stage trailer of claim 16, wherein the lower deck
has a plurality of tie-down structures adapted for securing cargo
items thereto.
20. The mobile stage trailer of claim 16, wherein the upper and
lower decks define a cargo space therebetween, and wherein the
trailer further comprises a plurality of closure panels for
enclosing the cargo space.
21. The mobile stage trailer of claim 16, wherein the chassis has a
plurality of leveling jacks selectively operably engagable with the
ground for supporting and leveling the stage trailer.
22. The mobile stage trailer of claim 16, wherein the chassis has a
plurality of leveling indicators for determining whether the stage
trailer is disposed in a level condition.
23. The mobile stage trailer of claim 16, wherein each wing deck
has a plurality of selectively positionable support legs operably
attached thereto.
24. The mobile stage trailer of claim 23, wherein each of the
plurality of support legs includes means for adjusting the length
of the support leg.
25. The mobile stage trailer of claim 16, further comprising means
for attaching at least one modular stage component to the
trailer.
26. The mobile stage trailer of claim 16, wherein the upper deck
and each wing deck are at least partially covered with anti-slip
material.
27. A mobile stage system comprising: a tow vehicle; and a trailer
including: a chassis having a pair of ground engaging wheels, a
first deck, and means for receiving and securing a plurality of
accessory items, the chassis presenting a chassis width dimension;
means for selectively coupling the trailer with the tow vehicle;
and a pair of wing decks operably coupled with the chassis, each
wing deck selectively shiftable between a first favored position
proximate the first deck of the chassis wherein the first deck and
the wing decks together present an upwardly directed surface for
performances and a second favored position for towing wherein the
trailer presents a towing width dimension, the towing width
dimension being generally equal to or less than the chassis width
dimension.
28. The mobile stage system of claim 27, wherein the tow vehicle is
a light truck.
29. The mobile stage system of claim 27, wherein the means for
receiving and securing a plurality of accessory items comprises a
second deck disposed below and spaced apart from the first deck,
the first and second decks defining a cargo space therebetween.
30. The mobile stage system of claim 29, wherein the second deck is
at least partially covered with an anti-slip surface material.
31. The mobile stage system of claim 29, wherein the means for
selectively coupling the trailer with the tow vehicle comprises a
hitch assembly operably coupled to the chassis.
32. The mobile stage system of claim 31, wherein the hitch assembly
is selectively operably positionable in a first extended position
wherein the hitch assembly is projecting forwardly from the chassis
and in a second retracted position wherein substantially all of the
hitch assembly is disposed under the second deck of the
chassis.
33. The mobile stage system of claim 27, wherein the plurality of
accessory items includes at least one item selected from the group
consisting of a guardrail, a railing, a stair, a canopy, a modular
stage component, and a shell.
34. The mobile stage system of claim 27, wherein the first deck and
the pair of wing decks are at least partially covered with an
anti-slip surface material.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application Serial No. 60/416,954 entitled "Lightweight
Portable Stage", filed Oct. 7, 2002, hereby fully incorporated
herein by reference.
FIELD OF THE INVENTION
[0002] The present invention is directed to a portable stage, and
more particularly to a lightweight mobile trailer based stage that
is towable with a light vehicle and that can be deployed and used
by one individual.
DESCRIPTION OF THE RELATED ART
[0003] Outdoor speeches, concerts, and other public performances
are commonplace in everyday life. Often, these performances are by
an individual performer, or a small group of performers, before a
small audience. It is usually advantageous for the performer to be
positioned higher than the audience on a platform or stage for
better visibility and sound quality.
[0004] Numerous examples of portable stage assemblies have been
previously disclosed in the art. One example of a previous portable
stage assembly is disclosed in U.S. Pat. No. 6,006,680 to Quam. The
portable stage platform disclosed therein has a performance
platform with a plurality of collapsible legs coupled to the
underside of the platform. This device may be relatively difficult
to use on uneven ground such as may be encountered at some outdoor
venues, however, because it rolls on casters and does not have
provisions for towing by a motor vehicle.
[0005] In U.S. Pat. No. 5,848,501, a modular portable stage system
is disclosed. U.S. Pat. No. 5,848,501 is commonly owned by the
owners of the present invention and is hereby fully incorporated
herein by reference. This portable stage system includes a number
of standardized modular components that can be used to construct a
platform that is easily adaptable to a wide variety of designs. The
components, although collapsible or capable of disassembly, must be
individually set-up and are not packaged so as to be easily
deployable by an individual.
[0006] Some prior devices have been built on a trailer, towable by
a motor vehicle. One example of such a prior device is disclosed in
U.S. Pat. No. 3,620,564 to Wenger, et. al., which patent is
commonly owned by the owner of the present invention and hereby
fully incorporated herein by reference. Other examples are
disclosed in U.S. Pat. No. 5,078,442 to Rau, et. al., reissued as
U.S. Reissue Pat. No. RE34,468, U.S. Pat. No. 5,152,109 to Boers,
U.S. Pat. No. 5,546,709 to Decker et. al., U.S. Pat. No. 6,176,495
to Decker, each commonly owned by the owner of the present
invention and likewise fully incorporated herein by reference. Yet
another example is the portable stage disclosed in U.S. Pat. No.
6,393,769 to Mertik, et. al. These are generally large and heavy
devices, however, and typically require relatively heavy vehicles
for towing and transport. Also, their large size and weight makes
deployment by an individual difficult.
[0007] Previous smaller scale trailer based mobile stages have
likewise not been entirely satisfactory. Even with a small stage,
it is typically desirable to carry accessory items for use with the
stage, such as railings, access stairs, skirting and the like.
Musical performances may require bulky or heavy items such as large
audio amplifiers and lights. Exhibits, such as for art fairs and
festivals, may involve significant amounts of merchandise and bulky
display structures. Previous small mobile stages typically have had
no, or very limited, ability to carry these items, requiring them
to be transported in the tow vehicle or separately.
[0008] What is still needed is a small-scale self-contained mobile
stage system for outdoor performances transportable with a light
tow vehicle, with features for easy deployment by one person
alone.
SUMMARY OF THE INVENTION
[0009] The present invention substantially meets the needs of the
industry by providing a small-scale self-contained mobile stage
system for outdoor performances transportable with a light tow
vehicle, with features for easy deployment by one person alone. In
the invention, a mobile stage trailer adapted for towing by a light
tow vehicle includes a chassis having a pair of decks including an
upper deck and a lower deck vertically spaced apart from the upper
deck. A hitch assembly is operably coupled with the chassis for
selectively coupling the trailer with the tow vehicle. A wing deck
is operably coupled with the chassis at each lateral edge of the
chassis. The wing decks are selectively positionable in a first
favored position proximate the upper deck of the chassis portion so
that the upper deck and the wing decks together present an upwardly
directed surface for performances. The wing decks are further
selectively positionable in a second favored position for towing
wherein the system presents a system width dimension generally
equal to the width of the chassis alone.
[0010] The portable stage of the present invention may be capable
of deployment in outdoor locations having uneven or soft ground.
The apparatus includes a lightweight chassis having a structural
frame and deck with high load-bearing capacity and low deflection.
The stage has a deck for transporting cargo and another deck that
forms a portion of the performance surface of the stage. The stage
may have one or more fold-out wing decks that may be alternately
configured in an position for towing, and in a performance position
substantially co-planar with the upper deck of the chassis. The
fold-out wing deck portions may also be optimized for light weight,
high strength and low deflection. In the performance position, the
wing portions enlarge the performance surface of the stage. The
lower deck provides cargo space to securely store and transport
accessories and other items that may be needed for a
performance.
[0011] The portable stage of the present invention is easily
deployed and used by an individual. The stage is lightweight,
making it easily maneuverable by an individual by hand, and may be
towed with a light duty vehicle such as an automobile or light
truck. Lift assist means are provided to assist an individual in
raising and lowering the wing portions. All supports and jacks for
leveling and stabilization of the stage apparatus may be operable
by an individual without assistance from others.
[0012] The stage may be used with other portable stage assemblies
to form larger performance surfaces and may also be used with
modular portable stage components. The hitch assembly is removable
or retractable to facilitate attachment of the stage to other
portable stages or components. In addition, a variety of
accessories, such as a lightweight overhead weather covering,
access stairs, and guardrails may be used with the stage.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a side elevation view of the lightweight portable
stage of the present invention with the stage configured for
towing;
[0014] FIG. 2 is a perspective view of the stage configured for
towing;
[0015] FIG. 3 is a perspective view depicting a selectively
positionable stage leveling jack positioned in a stage transport
position;
[0016] FIG. 4 is a perspective view of the stage leveling jack of
FIG. 3, with the jack positioned for leveling the stage;
[0017] FIG. 5 is a perspective view of a front portion of the
portable stage depicting a retractable hitch assembly in the
extended position;
[0018] FIG. 6 is a perspective view of the retractable hitch
assembly of FIG. 5, depicting the hitch in a disassembled and
retracted condition;
[0019] FIG. 7 is a top cutaway plan view of the retractable hitch
assembly in the extended position;
[0020] FIG. 8 is a top cutaway plan view of the retractable hitch
assembly in the retracted position;
[0021] FIG. 9 is a rear elevation view of the stage depicting
deployment of the wings from a folded-up towing or transport
position to a folded-down performance position;
[0022] FIG. 10 is a side elevation view of an adjustable length leg
assembly according to the invention;
[0023] FIG. 11 is a cut-away cross section view of a portion of the
adjustable length leg assembly depicted in FIG. 10;
[0024] FIG. 12 is a perspective view of a cargo tie-down track and
tie-down ring assembly;
[0025] FIG. 13 is a perspective view of tie down track cover strips
fitted into the cargo track of FIG. 12;
[0026] FIG. 14 is a perspective view of the chassis portion with
the wings in the folded-out position;
[0027] FIG. 15 is an view of a corner portion of the stage;
[0028] FIG. 16 is a side elevation view of the clamp portion of a
detachable railing in an initial stage of installation on an edge
of the stage;
[0029] FIG. 17 is a side elevation view of the clamp portion of the
detachable railing in intermediate and final stages of installation
on an edge of the stage;
[0030] FIG. 18 is a partial perspective view of the portable stage
assembly and accessories in a fully deployed configuration; and
[0031] FIG. 19 is a view of the stage with a weather protective
canopy installed thereover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] Portable stage 20 according to the present invention
generally includes main portion 22, and a pair of wing portions 24,
26 connected to main portion 22 with hinges 28. Main portion 22
generally includes chassis 30 and wheel assembly 32. Chassis 30
generally includes upper frame 34 and lower frame 36, which are
spaced apart and secured together by uprights 38. Upper frame 34
and lower frame 36 may be constructed from hollow metal shape
stock, preferably rectangular tube stock. Each frame 34, 36, has a
pair of side rails 40, which are spaced apart at opposite sides of
the frame 34, 36. Lateral support members 42 span between the pair
of side rails 40. Purlins 44 stabilize and provide bracing for
lateral support members 42. Upper frame 34 supports upper deck 46,
which presents a portion of performance surface 48. Lower frame 36
supports lower deck 50, which presents cargo surface 52. Cargo area
54 is defined between upper deck 46 and lower deck 50. It is most
preferred that upper deck 46 be positioned at about 36 inches above
ground level when stage 20 is deployed.
[0033] Cargo surface 52 may be fitted with suitable tie-down points
56 for securing items of cargo. For example, as depicted best in
FIG. 12, one or more slotted tie down strips 58, commonly known as
"airliner tracks" may be fastened to cargo surface 52. One or more
ring assemblies 60, which are adapted to cooperate with tie down
strips 58, may be inserted as depicted in FIG. 12. Tie down straps
61 may then be looped through the ring assemblies 60 and around the
cargo to be secured, which may be accessories such as railing
section 214. A layer 62 of a high-friction material such as
rubberized polymer may be provided on all or selected portions of
cargo surface 52 to frictionally contact and inhibit sliding of
items placed on cargo surface 52.
[0034] Removable or hinged enclosure panels 64, as depicted in FIG.
2, may be provided to partially or completely enclose cargo area
54. Panels 64 may be provided with a latch handle 66 to enable
securing of the panels 64 in place. Additionally, panels 64 may be
equipped with a lock 68 integral with latch handle 66 as depicted,
or as a separate assembly.
[0035] Each wing portion 24, 26, has a wing frame 70 constructed
from a pair of longitudinal members 72 and a number of spanning
lateral members 74. Purlins 76 are again provided for stabilization
and support of the lateral members 74. Each wing portion 24, 26,
has a deck 78, that forms a portion of performance surface 48.
[0036] The lightweight character of portable stage 20 is obtained,
in part, by the selection of materials for chassis 30 and wing
portions 24, 26. It is preferred that rectangular or square
aluminum tubing be used for upper frame 34, lower frame 36, and the
wing frames 70. Although the various component members can be
fastened together in any suitable manner, all-welded construction
is preferred for cost, strength, durability and weight purposes.
The preferred sizes of each member may be selected using standard
structural engineering methods. The structural components of the
stage are preferably designed so that the performance surface has a
design load bearing capacity of at least about 150 pounds per
square foot with a design deflection of no greater than L/240.
[0037] Also in keeping with the lightweight character and
relatively low cost of the device, it is preferred that upper deck
46, lower deck 50, and wing decks 78 be formed from aluminum sheet
material of suitable thickness so as to have appropriate load and
deflection characteristics. Other metal, polymer or composite sheet
materials having the appropriate strength and weight properties may
also be used for decks 46, 50, 78. A layer 80 of a high-friction
material such as rubberized polymer may be provided on all or
selected portions of performance surface 48 to frictionally contact
and inhibit sliding of items on performance surface 52 and to
prevent slips and falls. Again, one or more slotted tie down strips
58, such as airliner tracks may be fastened to performance surface
48 to facilitate securing cargo for transport. Removable covers 58a
may be provided as depicted in FIG. 13 to cover tie down strips 58
when stage 20 is used for performances, so as to alleviate any
tripping hazard.
[0038] The hinged connection of wing portions 24, 26, with main
portion 22 enables the wings to be folded in an upright towing
position as depicted best in FIG. 2, or deployed in a performance
position as depicted in FIG. 14. Hinge 28 may be a continuous hinge
fastened to the outer lateral surface of upper frame 34 and the
inner lateral surface of each wing portion 24, 26. Alternatively,
any other arrangement that enables hinging motion of wing portions
24, 26, with respect to main portion 22, including a number of
smaller, separate hinges or one or more strips of flexible,
resilient material, may be used.
[0039] Chassis 30 presents a maximum width dimension, annotated W1
in the Figures. To optimize the available width of performance
surface 48 while enabling legal towing of stage 20 over public
roads, it is generally preferred that chassis 30 present a maximum
width dimension W1 close to the maximum legal width dimension for
trailers in the locations where stage 20 will be used.
Consequently, it is also generally preferred that the overall width
W2 of stage 20, when wing portions 24, 26, are positioned in the
towing position, be no greater than the width W1 of chassis 30.
[0040] The folding motion of wing portions 24, 26, may be assisted
by a lifting device 86, such as gas cylinder 88. Gas cylinder 88 is
pivotally attached to an upper cylinder mount 90 on wing frame 70,
and pivotally attached to a lower cylinder mount 92 on chassis 30.
Gas cylinders 88 bias wing portions 24, 26, toward the towing
position depicted best in FIG. 9. The biasing force supplied by gas
cylinders 88 works to assist a user in raising and lowering the
wing portions 24, 26. For best results, it is currently preferred
that gas cylinders 88 be selected, based on the weight and size of
the wing portion, so that a force of no more than 100 pounds
applied to the outer edge of the wing portion is necessary for
either raising or lowering the wing. To resist movement of wings
24, 26, from wind or shock forces during transport, removable wing
braces 94 may be installed to brace and support the wings in the
towing position as depicted in FIGS. 5 and 13. Wing braces 94 may
be held in place with threaded fasteners or with any other suitable
means.
[0041] Each wing portion 24, 26, when deployed as depicted in FIG.
3, is supported by hinge 28 at inner edge 96 and by folding wing
support legs 98 at outer edge 100. Each wing support leg 98,
depicted best in FIGS. 10 and 11, generally includes a hollow upper
leg 102 and a hollow lower leg 104. The inner cross-section of
upper leg 102 is dimensioned so as to slidingly receive lower leg
104 axially within. At the bottom end 106 of lower leg 104 is foot
assembly 108, which generally includes an attachment portion 110 in
the form of a web 112 and a ground-engaging plate 114. Foot
assembly 108 is pivotally attached to lower leg 104 at pivot 115,
enabling foot assembly 108 to be folded so that the plane formed by
ground-engaging plate 114 parallels the longitudinal axis presented
by lower leg 104, designated a-a in the Figures. In a preferred
embodiment ground-engaging plate 114 has an area of at least about
35 square inches to enable appropriate load spreading and prevent
the leg from sinking into soft ground. At the top end 116 of upper
leg 102 is upper leg bracket 118, which is attached to wing frame
70. Upper leg bracket 118 is pivotally attached to upper leg 102 at
pivot 120, so that wing support leg 98 may be folded substantially
parallel with the wing frame 70. Latches, clips or other fastening
devices, such as straps 119, may be provided to secure the wing
support legs 98 against wing frame 70 when the stage 20 is in
transport.
[0042] The length of each wing support leg 98 may be adjustable.
Lower leg 104 has a series of regularly-spaced apertures 122 formed
therethrough. It is preferred that apertures 122 be formed
approximately 1/4" apart so as to enable a sufficiently fine degree
of adjustment. Upper leg 102 has a single corresponding aperture
124. Apertures 122 and aperture 124 are dimensioned so as to
receive a pin 126, and enable its insertion therethrough. Pin 126
has a handle 130. In use, lower leg 104 may be slid in and out of
upper leg portion 102 until the desired length is reached. The
nearest aperture 122 may then be aligned with aperture 124, and pin
126 may be inserted though the apertures 124, 126, so that distal
end 128 of pin 126 projects through the opposite side of wing
support leg 98 from which it was inserted. When it is desired to
readjust the length of the wing support leg 98, pin 126 may be
withdrawn by pulling handle 130 away from leg 98. The length of
each wing support leg 98 may thereby be adjusted to accommodate
ground of varying elevation, while still maintaining the wing
portion 24, 26, in a stable, level condition.
[0043] It is currently anticipated that the entire lightweight
portable stage apparatus will preferably have an empty weight of
from about 1,800 pounds to about 3,200 pounds, dependent on the
number of axles and the area of the performance surface provided.
The gross vehicle weight for the stage, fully loaded with cargo, is
anticipated to preferably be from about 3,000 pounds to about 7,000
pounds. It is anticipated that the size of the performance surface
48 may range up to about 400 square feet in area. Stage 20 is
capable of being towed by a light tow vehicle, generally including
half-ton or even quarter-ton pickup trucks and vans.
[0044] Main portion 22 may be stabilized in place and leveled using
jacks 132 disposed at each of the four corners 134 of main portion
22, as is best depicted in FIGS. 2-4 and 14. Jacks 132 may be any
type of jack as are well-known in the art and commonly used for
trailer leveling applications. Each jack 132 includes an upper body
portion 136, and a lower body portion 138 axially movable within
upper body portion 136. Crank handle 140 is attached at the upper
end of upper body portion 136. Rotary cranking motion applied to
crank handle 140 causes lower body portion 138 to move
longitudinally in and out of upper body portion 136, depending on
the direction of rotary motion. Ground engaging plate 142 is
attached to lower body portion 138. Moreover, upper body portion
136 is attached to stage main portion 22 with mounting bracket 146.
Pivot 148 is provided to enable the entire jack 132 to be pivoted
up to ninety degrees in the direction of the arrow, as depicted in
FIGS. 2 and 4. Jack 132 may be secured to pivot 148 with a
removable pin 150. Leveling indicators 152, which may be common
spirit type levels, are provided at each corner 134 of chassis 30,
so as to provide a reference enabling a user to easily level the
stage using jacks 132.
[0045] Stage 20 has features enabling it to be towed over public
roads by a light duty vehicle, such as an automobile or light
truck. An axle assembly 154 is provided, and generally includes a
pair of wheel assemblies 156 disposed at each end of an axle 158.
Each wheel assembly 156 includes a pneumatic tire 160 mounted on a
wheel 162. Tire 160 may be any suitably sized standard tire
manufactured for use with a utility trailer, automobile, or light
truck. Similarly, wheel 162 may be any automotive type wheel of
suitable size and that is compatible with tire 160, such as for
example, a standard steel or aluminum automobile wheel with a 4, 5,
or 6 bolt pattern. A fender 164 is provided over each wheel
assembly 156 to deflect road spray and rocks that may be thrown by
the tires.
[0046] Each wheel assembly 156 is bolted or otherwise attached to a
hub 166. The hubs 166 are fastened to opposite ends of axle
assembly 158. Axle 158, which may be any axle assembly of a type
commonly used for trailers, is secured with U-bolts 168 to a pair
of leaf springs 170. Leaf springs 170 are, in turn, attached to the
underside of chassis 30, and provide a spring suspension for
absorbing road shock and vibration during towing. Although not
depicted, shock absorbers may also be added to provide dampening
for the springs and a smoother ride quality. Of course, it will be
appreciated that any other suitable known suspension arrangement
may be used. For example, coil springs, coil-over shock absorbers,
struts, torsion bars, or any other resilient suspension element may
be used in place of leaf springs 170. Axle assembly 158 may also be
rigidly mounted to chassis 30, although ride quality would be
severely degraded. Moreover, axle assembly 158 may be replaced, for
example, by a differential assembly, or hubs 166 may be
independently suspended. Electric or hydraulic brakes may be
provided in hubs 166 to provide suitable stopping ability for the
device. A second, tandem, axle assembly 172 may also be provided to
increase the load capacity of the device, as depicted in FIG.
1.
[0047] At the front of chassis 30, hitch assembly 174 is provided
as a means of attaching the stage 20 to a tow vehicle 208 for
purposes of towing. Hitch assembly 174 generally includes a tongue
178 and a ball receiver 180. As depicted in FIG. 3, ball receiver
180 is a standard component as is commonly used with utility
trailers, and is adapted to fit over a ball 182 attached to the
towing vehicle. Although any suitably sized ball may be used, it is
currently anticipated that a 2{fraction (5/16)}" inch ball will
provide the best results. Latch 184 secures ball receiver 180 over
ball 182. A hitch jack 185 may be provided on tongue 178 to elevate
and support hitch assembly 174 during hitching and unhitching
operations. Hitch jack 185 has a ground engaging wheel 186, which
has a suitable ground contact patch so as to spread the tongue
weight and prevent the jack from sinking into soft ground. The
hitch jack 185 operates in a similar fashion to screw jacks 132 as
previously described, and is raised and lowered by rotary motion
imparted to crank 188. Hitch jack 185 may be detachable to enable
hitch assembly 174 to be retractable as depicted in FIGS. 5-8.
[0048] Hitch assembly 174 may be retractable to a position
underneath chassis 30, as depicted best in FIGS. 5-8, so as to
enable the attachment of additional platform sections as will be
further described herein below, and to facilitate access around the
perimeter of stage 20. In this embodiment, hitch housing 190 is
attached to chassis 30 below lower deck 50. Hitch housing 190 has
sides 192, bottom panel 194, and an open front 196. Hitch assembly
174 is received in hitch housing 190, extending through open front
196, and is slidable fore-and aft as depicted in FIG. 7. Hitch
assembly 174 is selectively positionable in a first extended towing
position wherein hitch assembly 174 extends forwardly from chassis
30 as depicted in FIG. 7, and a second retracted or stowed position
wherein all or a substantial portion of hitch assembly 174 is
within housing 190 beneath lower deck 50 as depicted in FIG. 8.
Pins 198 extend through apertures 200 in housing 190 on each side
192, engaging corresponding apertures (not depicted) in hitch
assembly 174 to secure it in place when hitch assembly 174 is
positioned in the extended position as depicted in FIG. 7. Cutout
202 may be provided to facilitate access to hitch assembly 174 for
positioning.
[0049] Hitch assembly 174 may also include a suitable electrical
connection cable 204 for connection with a vehicle electrical
system to provide power and signals for running lights 205 and the
brakes. Safety chains may also be included.
[0050] It will be appreciated that a variety of alternatives to the
described ball hitch arrangement exist for attaching the
lightweight portable stage to a vehicle. For example, a pintle
hitch or gooseneck arrangement could be used, with a suitably
equipped towing vehicle.
[0051] The operation and use of stage 20 may now be understood with
reference to FIGS. 1-19. With the stage 20 configured for towing as
depicted in FIGS. 1 and 2, an individual user may hitch the stage
20 to a suitably equipped vehicle 208 by elevating hitch jack 185
to a sufficient height so as to clear the vehicle ball 182,
positioning the vehicle 208 so that the ball 182 is under ball
receiver 180, lowering hitch jack 185 so that ball receiver 180
engages ball 182, and closing latch 184 to secure ball 182 in
place. Stage 20 may then be towed to a desired location using
vehicle 208. Once in location, stage 20 may be unhitched from
vehicle 208 by the user using the reverse of the procedure
described above. Jacks 132 are lowered so as to engage the ground
surface, and the stage is leveled using jacks 132 and with
reference to leveling indicators 152. Once main portion 22 is
leveled, wing portions 24, 26, may then be unlatched and lowered
into a position generally coplanar with upper deck 46 of main
portion 22, forming performance surface 48. Wing portions 24, 26,
are lowered by grasping outer edge 210 and pulling downward. Gas
cylinders 88 provide a resisting force so as to support a portion
of the weight of wing portions 24, 26, and enable an individual
user to easily support wing 24, 26, as it lowers. Once each wing
portion 24, 26, is lowered, wing support legs 98 may be pivoted
downward and adjusted for length so that plate 114 of each leg
engages the ground and the wing portion is substantially level with
upper deck 46.
[0052] Suitable accessories, for example steps 210, and railings
212 may be attached to stage 20 as desired. Each section 214 of
railing 212 generally includes a pair of uprights 216 connected by
a top rail 218, a mid-rail 220, and a lower rail 221. Each upright
216 has a c-clamp assembly 222 for attaching to stage 20. C-clamp
assembly 222 generally includes upper jaw 224, which may welded
directly to upright 216, and a lower jaw portion 226 which slides
over lower end 228 of upright 216. Lower jaw portion 226 has notch
230, which is dimensioned to receive structural member 232 at an
edge of stage 20, which may be part of upper frame 34 of chassis 30
or of wing frame 70. Lower jaw portion 226 also includes threaded
t-handle lever 234, which is slidable in elongate slot 236. Once
upper jaw 224 and lower jaw portion 226 are engaged around an edge
of stage 20, threaded t-handle lever 234 may be slid under lower
jaw portion 226 and tightened to clamp structural member 232
tightly between upper jaw 224 and lower jaw portion 226, thereby
securing railing section 214 on the edge of stage 20. Accessories,
including steps 210 and railing sections 214 may stowed in cargo
area 54 or on upper deck 46 and secured with tie down straps to
prepare stage 20 for transport.
[0053] As an alternative to railing 212 described above, a railing
as is described in U.S. Pat. No. 5,263,550 may be used. U.S. Pat.
No. 5,263,550 is commonly owned by the assignee of the present
invention, and is hereby fully incorporated herein by
reference.
[0054] In addition, a weather protective canopy may be deployed to
cover the performance surface 48 as depicted in FIG. 19. As
depicted, fabric canopy 242 is supported and secured in tent-like
fashion over a lightweight space frame 244. It is currently
preferred that fabric canopy be fashioned from canvas, but other
suitable materials such as rip-stop nylon may also be used.
[0055] A fabric towing cover 246 may be provided to cover and
protect stage 20 from moisture and road debris when stage 20 is
configured for towing. Cover 246 may be secured to chassis 30 with
straps 248.
[0056] Moreover, the available area of performance surface may be
increased by positioning one of more stages 20 in proximity to each
other, or by using modular stage components such as are disclosed
and depicted in U.S. Pat. Nos. 5,848,501 and 6,106,186, both of
which are commonly owned by the assignee of the present invention,
and both of which are hereby fully incorporated by reference
herein. As will be appreciated, the attachment apparatus and
methods disclosed therein may be applied to attach multiple
lightweight portable stages 20 together, and to attach modular
components to the stages.
[0057] As will also be appreciated, a variety of alternative
configurations of the lightweight portable stage are possible.
Although the embodiments depicted herein include a main portion 22
with a pair of laterally disposed wing portions, 24, 26,
embodiments having no wing portions, one wing portion, or any other
number of wing portions are also possible. As an alternative, wing
portions could also be configured so as to fold outward from the
fore and/or aft ends of the chassis if desired.
[0058] The present invention has been described with respect to
particular illustrative embodiments. It is to be understood that
the invention is not limited to the above-described embodiments and
modifications thereto, and that various changes and modifications
may be made by those of ordinary skill in the art without departing
from the spirit and scope of the appended claims.
* * * * *