Portable aircraft maintenance platform

TECHNICAL FIELD

[0001] The present invention relates generally to scaffolds and work platforms. More particularly, this invention relates to a new and unique aircraft maintenance platform of modular construction for knockdown and portability.

BACKGROUND ART

[0002] A variety of scaffolds have been available heretofore. Such scaffolds generally include rigid frames that can be stacked and interconnected together to form an elevated work platform of the desired height, such as for working on walls, ceilings, chimneys or windows of a building, for example. Such scaffolds are generally transported by truck in pieces to the work site for assembly. When assembled, they are generally free-standing, but tend to be rather heavy for adequate strength, rigidity and stability. Such scaffolds usually have adjustable feet for leveling purposes, and may have lockable casters to facilitate location and relocation as desired.

[0003] While the scaffolds of the prior art generally provide elevated work platforms, they do not accommodate much lateral extension during use. They become more top heavy with height and particularly with workers on them in use. The scaffolds of the prior art can become unstable and even tip over if a worker leans out too far. Sometimes they can be temporarily attached to the adjacent structure for safety, such as in a building construction project, but are most often used to access areas directly overhead or immediately next to the scaffold.

[0004] Various specialized scaffolds have also been available heretofore. For example, U.S. Pat. No. 4,592,447 shows a movable pedestal scaffold. U.S. Pat. No. 4,194,591 shows a mobile scaffold with fixed-use-position outriggers. U.S. Pat. No. 4,155,424 shows a mobile scaffold with a main frame and pivotal outer frames so that it can be rolled through narrows doors or aisles. U.S. Pat. Nos. 3,454,131, 2,665,950 and 2,438,173 also show scaffolds representative of the prior art.

[0005] Aircraft maintenance requires the use of specialized scaffolds in order to access areas that cannot otherwise be reached. For example, there may be certain access doors or other areas that cannot be reached without specialized scaffolding due to the aircraft's configuration. Little or no maintenance work can or should be done while standing on the aircraft itself. The scaffolding cannot be temporarily attached to the aircraft as is typical in building construction. As a result, such specialized scaffolds or work platforms must be free-standing, and thus tend to be rather cumbersome and heavy in order to achieve the stability necessary for working in an elevated position over part of the aircraft. Further, different scaffolds or work platforms are usually required for maintaining different types of aircraft, particularly with helicopters and fixed wing aircraft, whose configurations are quite different.

[0006] Such scaffolds or work platforms have not been adapted for use on different aircraft types as needed, and are not readily transportable. They have thus tended to be limited for use in hangars where they are stored. This in turn means that the aircraft must be flown to a facility where the hangar is located for all but the most basic maintenance, resulting in unnecessary downtime and expense. Such logistics problems are severe in military applications due to the variety of aircraft types in service, and the fact that some aircraft, such as helicopters, typically operate in the field. This has been compounded by the fact that aircraft systems today are more complex and require more frequent maintenance for readiness.

[0007] Heretofore there has not been available a portable aircraft maintenance platform that is readily adapted for use on different aircraft types, either on a prepared surface such as in a hangar or on an unimproved surface, such as in the field at a forward base as in military applications.

[0008] A need has thus arisen for a portable aircraft maintenance platform that is readily adapted for use on different aircraft types, either on a prepared surface such as in a hangar, or on an unimproved surface, such as in the field, and which is of modular construction for knockdown and portability so that more maintenance can be done in the field at the point of need.

SUMMARY OF INVENTION

[0009] The present invention comprises a portable aircraft maintenance platform that overcomes the foregoing and other difficulties associated with the prior art. In accordance with the invention, there is provided an aircraft maintenance platform of lightweight, modular construction so that it can be assembled, disassembled, and packaged for air, vehicle or manportability by one or two persons. The maintenance platform herein includes a basic main frame to which other modules can be added as desired to enhance overall versatility and function. The main frame includes two lower sections and two upper extensions interconnected by various braces, couplers and clips. An adjustable balcony and a lower stabilizer can be mounted on one side of the main frame, if desired, depending upon the type of aircraft to be maintained. The modules are interconnected by various releasable connectors, all of which can be done manually without tools, so that the platform can be configured as desired and yet still be capable of knockdown and repacking for transport to another site as needed. The present invention is particularly adapted for use in commercial and military applications conducted in remote or unimproved locations where packaging for transportation is critical, and is capable of rapid assembly into multi-functional structural combinations to suite site-specific and configuration-specific needs meeting aircraft and vehicle requirements.

BRIEF DESCRIPTION OF DRAWING

[0010] A better understanding of the invention can be had by reference to the following Detailed Description in conjunction with the accompanying Drawing, wherein:

[0011]
FIG. 1 is an illustration of the portable aircraft maintenance platform of the invention, one positioned in front of and another positioned next to a helicopter;

[0012]
FIG. 2 is a perspective view of the portable aircraft maintenance platform and balcony module herein;

[0013]
FIG. 3 is a side elevational view of the portable aircraft maintenance platform and balcony module herein;

[0014]
FIG. 4 is a partially exploded perspective view of the portable aircraft maintenance platform and balcony module herein;

[0015]
FIG. 5 is a fully exploded perspective view of the portable aircraft maintenance platform herein;

[0016]
FIG. 6 is an exploded, detail view of an adjustable leg;

[0017]
FIG. 7 is an enlarged side view of one end of a brace connected to a frame section;

[0018]
FIG. 8 is an enlarged side view of one end of a walkway connected to a frame section;

[0019]
FIG. 9 is an exploded perspective view of a frame clamp;

[0020]
FIG. 10 is an exploded perspective view of a load transfer coupler;

[0021]
FIG. 11 is an exploded perspective view of the connection between the upper and lower base frames;

[0022]
FIG. 12 is a partial perspective view of the inner balcony frame;

[0023]
FIG. 13 is a partial perspective view of the outer balcony frame;

[0024]
FIGS. 14 and 15 are exploded perspective views of the stabilizer;

[0025]
FIG. 16 is an perspective view showing an alternate clamp;

[0026]
FIG. 17 is a perspective view of the portable aircraft maintenance platform herein with outriggers;

[0027]
FIG. 18 is an illustration of the portable aircraft maintenance platform herein disassembled and ready for packing in cases as a kit for transportation; and

[0028]
FIG. 19 is a perspective view, partially cutaway, showing details of the large transport case for then platform.

DETAILED DESCRIPTION

[0029] Referring now to the Drawing, wherein like reference numerals designate like or corresponding elements throughout the views, and particularly referring to FIG. 1, there is shown a portable aircraft maintenance platform 10 incorporating the invention. The platform 10 is of modular construction, and is adapted primarily for use with aircraft, such as a helicopter as shown, but can also be used with fixed wing aircraft or other types of vehicles. As will be explained more fully hereinafter, the platform 10 can be arranged in various configurations for maximum versatility, while also being adapted for portability and manual assembly/disassembly without tools.

[0030] Referring primarily to FIGS. 1-6, the platform 10 includes a main frame 12 comprising two base frames 14 and 16 which are clamped together to form a rigid assembly. The main frame 12 is preferably comprised primarily of lightweight tubing, such as 6062T6aircraft grade aluminum of about two inch diameter and 0.025 in wall thickness, although any suitable material could be used.

[0031] Each rigid base frame 14 and 16 includes two ladder-like ends 18, each of which includes two laterally spaced uprights 20 interconnected by vertically spaced-apart rungs 22. As shown five rungs 22 are provided, although any suitable number could be used. In the preferred embodiment, each end 18 is about 26 inches wide and about 78 inches tall. A gusset or flat crosspiece 24 is preferably provided beneath the upper rung 22 for carrying assembly instructions.

[0032] Vertically adjustable legs 26 are provided in the lower ends of uprights 20 for leveling attachment, to which are attached lockable swivel casters 28 for use on a hard surface. Swivel platforms 30 can be substituted for casters 28 if platform 10 is to be used in the field on an unimproved surface.

[0033] The ladder-like frame ends 18 are interconnected by diagonal and horizontal cross braces 32 and 34 coupled between rungs 22. In the preferred embodiment, the ends are spaced apart about 98 inches. The ends of each brace 32,34 are curved with spring clips 36 therein so as to positively snap onto the adjacent rung 22, as best seen in FIG. 7.

[0034] Base frame 14 also includes a walkway 38 connected between the rungs 22. Walkway 38 preferably includes a wooden surface 42 secured to the tops of rails 42, the ends of which are notched to fit over rungs 22, as best seen in FIG. 8. In the preferred embodiment, slidable keepers 44 are also provided in the notched ends of rails 42 for positive, releasable attachment to rungs 22. The walkway 38 can thus be connected between any two opposite rungs 22 at the desired height.

[0035] Walkway 38 preferably includes a hinged access door 46, with a ladder 48 also preferably being provided for facilitating movement of personnel between the upper and lower walkways in platform 10. The upper ends of ladder 48 are preferably configured like the ends of braces 32 and 34 for releasable snap engagement with a rung 22 on one of the ends 18.

[0036] The base frames 14 and 16 are releasably secured together at each end by clamps 50 and load transfer couplers 52, the details of which are shown in FIGS. 9 and 10. In the preferred embodiment, two clamps 50 and one coupler 52 are used on each end of subframes 14 and 16. Each split clamp 50 includes mating halves 50a and 50b secured together over opposite sides of the adjacent uprights 20 of the subframes by bolts 54 and wing nuts 56 extending therebetween, as best seen in FIG. 9. The inside surfaces of split clamps 50 are configured for snug receipt of the uprights 20 therein, in parallel arrangement.

[0037] Each split load transfer coupler 52 includes mating halves 52a and 52b secured together over opposite sides of the adjacent uprights 20, as well as opposite rungs 22 of subframes 14 and 16 by bolts 58 and wingnuts 60, as best seen in FIG. 10. The inside surfaces of split couplers 50 are configured for snug receipt of the uprights 20 and their respective rung 22 therein, in perpendicular arrangement.

[0038] The use of inline clamps 50 and crisscross load transfer couplers 52 provides for proper load transfer and distribution between base frames 14 and 16 within main frame 12. This comprises a significant feature of the invention.

[0039] Upper frames 62 and 64 are mounted on the base frames 14 and 16, respectively for vertical extension as desired. Again, each upper frame 62, 64 includes two ladder-like ends 66, each having two laterally spaced uprights 68 interconnected by vertically spaced-apart rungs 70. As shown four rungs 70 are provided, although any suitable number could be used. In the preferred embodiment, each frame 62, 64 is about 26 inches wide and about 65 inches tall. Again, the ends 66 are interconnected by diagonal and horizontal cross braces 32 and 34 coupled between rungs 70 as desired to serve as guard rails. Again, clamps 50 are used to secure the upper frames together, two of which are preferably used on each end.

[0040] The upper ends of base frames 14,16 and the lower ends of upper frames 62,64 are adapted for telescoping, releasable locked engagement, as best seen in FIG. 11. In particular, the reduced lower ends of uprights 68 fit into the upper ends of uprights 20, to be interlocked by clips 72 extending through aligned holes 74 and 76 therein. As shown, each interlock clip 72 includes a collar 72a with an pin 72b therein. A second hole 78 is preferably provided below each hole 76 for storing clips 72 in unlocked position when not in use.

[0041] It will thus be appreciated that platform 10 can be assembled with or without the upper frames 62,64 as desired when more working height is needed. The braces 32,34 can be positioned as desired, as can the walkways 38 and ladder 48. The walkways 38 in upper frames 62 and 54 can be positioned at the same or different levels. If positioned at the same level, an extension 80 of generally T-shaped cross-section can be used to close the gap therebetween for better safety.

[0042] In the preferred embodiment, the upper ends of uprights 68 in each end 66 similarly include locking clips 72 and holes 74,76 so that additional upper frames 62,64 can be added, if desired. Additional clamps 50 and load transfer couplers 52 can also be used for additional rigidity.

[0043] Referring to FIGS. 2-5 in conjunction with FIG. 12, platform 10 preferably includes an adjustable balcony 82 for added versatility and lateral extension as desired. Balcony 82 is mounted on one side of mainframe 12, and includes inner frame 84 and outer frame 86. Inner frame 84 includes two rigid ladder-like ends 88, each of which includes two laterally spaced uprights 90 interconnected at their upper ends by vertically spaced-apart rungs 92, with a brace 93 secured between the lower rung and the relatively longer inner upright, as best seen in FIG. 12. As shown five, rungs 92 are provided, although any suitable number could be used. In the preferred embodiment, each end 88 is about 26 inches wide and about 100 inches tall overall.

[0044] The ends 88 of inner balcony frame 84 are each similarly connected to frames 16 and 64 by split clamps 50 and load transfer couplers 52, as shown. Two clamps 50 and one coupler 52 are preferably used on each inner balcony frame 84, although any suitable number could be used. In the preferred embodiment, one mating half 52b of each clamp 50 is welded or otherwise secured to the inner upright 90 in the desired position to facilitate assembly. The ends 88 are also interconnected by at least one horizontal brace 34, with a walkway 38 being connected between rungs 92 as desired.

[0045] Referring to FIGS. 2-5 in conjunction with FIG. 13, the outer balcony frame 86 similarly includes two rigid ladder-like ends 94, each of which includes two laterally spaced uprights 96 interconnected by vertically spaced-apart rungs 98 The outer balcony frame 86 is relatively narrower and shorter than the inner balcony frame 84. As shown four rungs 98 are provided, although any suitable number could be used. In the preferred embodiment, each end 94 is about 11 inches wide and about 46 inches tall.

[0046] Similarly, the ends 94 of outer balcony frame 86 are connected to the respective inner balcony frames 84 by split clamp 50 and couplers 52, as best seen in FIG. 13. Again, half of the clamp 50 is preferably welded or otherwise secured to the inner upright 96 in the desired position to facilitate assembly. The ends 94 are also interconnected by at least one horizontal brace 34, with a walkway 38 being connected between rungs 92 as desired, to provide a step. Since the outer balcony frame 88 is relatively narrower than the inner frame 84, the walkway 38 is connected and supported between rungs 92 and 98.

[0047] If the outer balcony frame 86 is not needed, then it can be omitted from balcony 82, along with the second walkway 38, in which case the brace 34 would be connected between ends 88.

[0048] Referring to FIGS. 14 and 15, when using balcony 82, or additional upper extension frames 62 and 64, a stabilizer 100 is also provided, which should be connected to the base frames 14 and 16 beforehand. The stabilizer 100 similarly includes two relatively long, but narrow ladder-like ends 102, each preferably including two vertically spaced-apart rungs 104 interconnected by five laterally spaced-apart uprights 106, although any suitable number could be used. In the preferred embodiment, each end 94 is about 104 inches long and about 4.5 inches tall. The inner balcony ends 102 are each preferably connected to frames 14 and 16 by two clamps 50, although any suitable number could be used. Adjustable legs 26 and swivel platforms 30 are provided at the outer ends 102 for leveling, with another cross brace 32 connected therebetween.

[0049] Referring to FIG. 16, there is shown an alternate clamp 110 which can be used instead of clamps 50 and couplers 52 to secure balcony 82 to the mainframe 12. Clamp 110 includes mating halves 110a and 110b connected at one side by a hinge 112. Each clamp half 110a is secured directly to the inner uprights 92. such as by welding, to facilitate assembly. The pivotal clamp half 110b is secured by means of a bolt 114, one end of which is pivoted to the other side of clamp half 110a and the outer threaded end of which is fits into a notch on the pivotal half 110b and is tightened by a wingnut 116.

[0050] Referring again to FIG. 17, corner outriggers 118 may used 10 under some conditions for additional stability, such when upper extension frames 62,64 are installed or when platform 10 is used in the field on a soft unimproved surface. Each outrigger 118 comprises a leg 120, the upper end of which is coupled to an upright of the respective end frame 18 similar to braces 32 and 34, with a pivotal foot 122 being provided on the lower end. A brace 124 is also similarly connected between each leg 120 and the respective upright 20, the inner end of which is preferably pivoted to the leg at 126 so that the outrigger 118 can be folded together when stowed and not in use.

[0051]
FIGS. 18 and 19 show the aircraft maintenance platform 10 in knocked-down condition ready for transportation in collapsible bags or cases 130, 132 and 134. Cases 130, 132 and 134 are preferably constructed of woven plastic, such as cordura nylon, for durability and light weight, although canvas or any suitable material could be used. The relatively smaller cases 130 and 132, which are of the same size, are adapted to carry the smaller components of platform 10, such the clamps 50, couplers 52, etc. In the preferred embodiment, cases 130 and 132 are each about 18 inches long by 18 inches wide by 6 inches deep, closable about three sides by a zipper 136 with a carrying handle 138 sewn to the top as shown. The cases 130 and 132 are dimensioned to fit between the rungs of the main frame 12 when packed into case 134, which is adapted to carry the larger/longer components of platform 10.

[0052] The details of the larger case 134 are best seen in FIG. 19. In the preferred embodiment, case 134 is about 110 inches long by 30 inches wide by 16 inches deep, closable about three sides by a zipper 140 with carrying handles 142 sewn to the sides and ends as shown. Internal inserts 144 are provided in the ends for puncture resistance. The inserts 144 can be formed of wood or other suitable material. Case 134 includes two longitudinal straps 146, which are preferably sewn along substantially the entire length of the case, the ends of which are secured by double D-rings near the zipper 140 as shown. Similarly, case 134 also includes two circumferential straps 148, which are preferably sewn about substantially the entire girth of the case, the ends of which are also secured by double D-rings near the zipper 140 as shown. Straps 142 and 144 can be formed from nylon webbing or other suitable material. A nameplate 150 and clear window inserts 152 are provided on the top of case 134 for identification and documentation as desired. Metal feet 154 are preferably riveted to the bottom of case 134 near the corners for durability.

[0053] From the foregoing, it will be appreciated that the present invention comprises a portable aircraft maintenance platform having several advantages over the prior art. The platform herein is of modular construction for ease of assembly, disassembly and transportation. The platform herein incorporates several common and/or interchangeable components to simplify assembly/disassembly quickly by hand without tools, in a variety of configurations depending on the particular aircraft or vehicle to be maintained. When disassembled, the platform herein can be readily stowed in compact shipping cases as a kit for portability. The platform herein can be configured or reconfigured as desired, for use on either improved or unimproved surfaces in the field. Other advantages will be evident to those skilled in the art.

[0054] Although particular embodiments of the invention have been illustrated in the accompanying Drawing and described in the foregoing Detailed Description, it will be understood that the invention is not limited only to the embodiments disclosed, but is intended to embrace any equivalents, modifications and/or rearrangements of elements falling within the scope of the invention as defined by the following Claims.

Portable aircraft maintenance platform

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