COMPOSITE MATERIAL MODULAR UTILITY VEHICLE CONSTRUCT

A modular utility vehicle construct that is light weight yet robust is provided. The construct is formed with a composite open area core sandwich structure capable of withstanding typical wear and tear and environmental elements experienced by utility vehicle compartments. The use of the composite sandwich structure allows for replacement of traditional materials such as steel or aluminum, without a loss of strength, in a vehicle's containment construct while also reducing the overall weight of the vehicle and increasing the ability to customize the vehicle's utility features to suit the specific needs of the purchaser.

FIELD OF THE INVENTION

The present invention in general relates to composite materials and in particular to a modular utility vehicle construct formed with a composite open area core sandwich structure.

BACKGROUND OF THE INVENTION

Weight savings in the automotive, transportation, and logistics based industries has been a major focus in order to make more fuel efficient vehicles. In order to reduce the weight of such vehicles, light weight composite materials have been introduced to take the place of typical metal structural and surface body components and panels. Composite materials are materials made from two or more constituent materials with significantly different physical or chemical properties, that when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure. A composite material may be preferred for many reasons: common examples include materials which are stronger, lighter, or less expensive when compared to traditional materials.

A sandwich-structured composite is a special class of composite material that is fabricated by attaching two thin but stiff skins to a lightweight but thick core. The core material is normally a low strength material, but its higher thickness provides the sandwich composite with high bending stiffness with overall low density. While sandwich structures have previously been developed to provide strength and reduced weight, the ability to obtain a vehicle exterior quality high gloss surface has remained a challenge, regardless of whether the surface outermost layer is thermoset resin or thermoplastic. Exemplary of these efforts are U.S. Pat. Nos. 5,087,500A, 4,803,108A, 8,091,286B2, 4,369,608A, 3,553,054A, and WO2018/202473. It is conventional to either not use such structures in settings where vehicle high gloss surfaces are required or resort to an additional outer layer to provide a high gloss outermost layer. Such outermost layers can be applied after structure production or through in mold coatings, both of which add to the cost and complexity of production.

Still another conventional problem with sandwich structures is that the edges are ineffective and allow for infiltration of humidity or moisture that becomes entrained within the core and often inconsistent with finished vehicle surface requirements. With temperature extremes this entrained moisture can reduce the operational lifetime of the structure, while increasing the weight thereof. These problems of moisture infiltration are particularly pronounced in instances when the core is formed of cellulosic materials such as paper. Accordingly, such composite structures have been unsuitable for forming exterior walls of vehicles given that such areas of a vehicle are openly exposed to the elements.

Utility vehicles are a class of vehicle for which replacement of typical metal structural and surface body components and panels with light weight composite materials has proven difficult. This is due in part to the rigorous conditions under which such vehicle are used, the variety of tasks such vehicle must be equipped for, and the versatility required of such vehicles.

Thus, there exists a need for a light weight yet robust modular utility vehicle construct capable of withstanding typical wear and tear and environmental elements experienced by utility vehicle compartments.

SUMMARY OF THE INVENTION

A modular utility vehicle is provided that includes a chassis having a front portion and a rear portion, and an operator cab fixed to the front portion of the chassis. The modular utility vehicle has a plurality of modular panels formed of a composite sandwich material having an open area core defining a plurality of pores, a surface sheet adhered to a first face of the open area core by a first adhesive layer, and a structural skin adhered to a second face of the open area core by a second adhesive layer, the plurality of modular panels forming a containment construct that is fixed to the rear portion of the chassis.

DESCRIPTION OF THE INVENTION

The present invention has utility as a light weight yet robust modular utility vehicle construct formed with a composite open area core sandwich structure capable of withstanding typical wear and tear and environmental elements experienced by utility vehicle compartments. The use of the composite sandwich structure allows for replacement of traditional materials such as steel or aluminum, without a loss of strength, in a vehicle's containment construct while also reducing the overall weight of the vehicle and increasing the ability to customize the vehicle's utility features to suit the specific needs of the purchaser.

According to embodiments, components for forming a modular utility vehicle construct are formed of a sandwich composite structure as detailed in co-pending U.S. Provisional Patent Application No. 62/774,600, filed on Dec. 3, 2018, the contents of which are hereby incorporated by reference. As described therein, embodiments of the sandwich composite structure provide a high gloss surface sheet and structural skin that are adhered to the open area core with an adhesive or glue that is viscous when applied. The viscosity of the adhesive as applied allows for contact with the interior volume of the open area core to create more adhesion surface area yet without excessively running into the pores defined in the open area core before the adhesive cured or hardens thereby providing greater adhered contact area between the components of the sandwich composite structure. As a result, reduced delamination of the components of the sandwich composite structure is observed as well as precluding bond line readthrough into the high gloss surface sheet. It is appreciated that providing a high gloss exterior surface without resort to an additional outmost layer requires a balancing of opposing surface tension properties of the composite sandwich panel structures to avoid a loss in tolerances associated with bowing of the structure. Thus, forming components for forming a modular utility vehicle construct out of such a composite sandwich structure also have utility as watertight and waterproof composite sandwich panel structures.

The present invention will now be described with reference to the following embodiments. As is apparent by these descriptions, this invention can be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. For example, features illustrated with respect to one embodiment can be incorporated into other embodiments, and features illustrated with respect to a particular embodiment may be deleted from the embodiment. In addition, numerous variations and additions to the embodiments suggested herein will be apparent to those skilled in the art in light of the instant disclosure, which do not depart from the instant invention. Hence, the following specification is intended to illustrate some particular embodiments of the invention, and not to exhaustively specify all permutations, combinations, and variations thereof.

Unless indicated otherwise, explicitly or by context, the following terms are used herein as set forth below.

As used herein, the term “high gloss surface” refers to a surface having minimal perceptible surface defects when visually inspected for about three seconds from about 24-28 inches from the viewer and normal to the part surface+/−90 degrees in a well-lit area. That is, the term “high gloss surface” refers to a surface capable of being painted and accepted as a “Class A” autobody part. This is commonly measured by ASTM D523. In the automotive industry, a Class A surface is a surface a consumer can see without functioning the vehicle (e.g., opening the hood or decklid), while a Class A surface finish generally refers to painted outer panels and specifically to the distinctness of image (DOI) and gloss level on the part. It is appreciated that a surface layer may be subjected to sanding, trimming, and priming prior to receiving a paint coating that imparts high gloss, yet must retain dimensionality and adhesion uniformity to primer and paint so as to achieve a high gloss finish.

FIGS.1-3show a rear perspective view of a modular utility vehicle100according to embodiments of the present invention. According to embodiments, a modular utility vehicle100includes a chassis102having a front portion104and a rear portion106, an operator cab108fixed to the front portion104of the chassis102, and a plurality of modular panels110formed of a composite sandwich material10, such as that shown inFIGS.4-7. The composite sandwich panel material10includes an open area core12with walls26defining an ordered array of pores24terminating in faces17and17′, a surface sheet14adhered to a first face17of the open area core12by a first adhesive layer20, and a structural skin16adhered to a second face17′ of the open area core12by a second adhesive layer22. The plurality of modular panels110together form a containment construct112that is fixed to the rear portion106of the chassis102. According to embodiments the containment construct112includes a floor assembly114, a wall assembly116, and a roof assembly118, each of the floor assembly114, wall assembly116, and roof assembly begin formed of at least one of the panels of the plurality of modular panels110.

In some inventive embodiments, a partition202is present between the operator cab108and the rear portion106. It is appreciated that the partition provides a safety function by protecting inhabitants of the operator cab108from contents of the rear portion106shifting forward during a sudden a stop or collision. The partition202is readily formed from materials illustratively including composite sandwich material10as detailed hereafter, sheet metal, sheet molding composition, or combinations thereof. In some inventive embodiments, the partition202include a door204to access the rear portion106from the operator cab108. The door is readily made of any of the materials from which the partition202is made. The door204is movably attached to the partition202with hardware206as hinged door, roller door, pocket door, or sliding door.

FIGS.4-7show a composite sandwich material10from which the plurality of modular panels110are formed. As shown inFIG.4, a portion of the surface sheet14is cutaway to reveal the adhesive20, a cloth, if present; and the open area core12. The surface sheet14is adhered to a first side of the open area core12by a first adhesive layer20. According to embodiments, the surface sheet14presents an outwardly facing high gloss surface15.FIG.5is an enlarged cross-sectional view of a composite sandwich panel material10used to form modular panels110that are assembled into the inventive modular utility vehicle100according to embodiments of the invention.FIG.5shows further details of the various layers making up the composite sandwich material10. In some embodiments, a cloth19is present intermediate between the face17of the open area core12and the surface sheet14, the cloth19being embedded within the adhesive20. The structural skin16is adhered to an opposing second side of the open area core12by a second adhesive layer22. In some embodiments, a cloth19′ is present intermediate between the face17′ of open area core12and the structural skin16, the cloth19′ being embedded within the adhesive22.

According to embodiments, the open area core12is formed of a lightweight material that defines a plurality of pores24so as to reduce the overall density of the open area core12. The open area core12is formed from a variety of materials that include cellulosics such as corrugated fiberboard, paper board, paper stock; thermoplastics such as poly(methyl methacrylate) (PMMA), acrylonitrile butadiene styrene (ABS), polyamides, polylactides, polybenzimidazoles, polycarbonates, polyether sulfones, polyethylene, polypropylene, polystyrene, polyvinyl chloride, and block copolymers of any one of the aforementioned where at least one of the aforementioned makes up the majority by weight of the copolymer and regardless of the tacticity of the polymer or copolymer; thermosets such as polyesters, polyureas, polyurethanes, polyurea/polyurethanes, epoxies, vinyl esters; metal such as aluminum, magnesium, and alloys of any one of the aforementioned where at least one of the aforementioned metals constitutes the majority by weight of the alloy; a foam formed from polyurethane, polyethylene, ethylene vinyl acetate, polypropylene, polystyrene, polyvinyl chloride, oraerogels, regardless of whether the foam is open-celled or closed-celled. The top edges of the walls26that define the pores24in certain embodiments of the open area core such as 12 form an array of various shapes, such as hexagonal, circular, rhomboidal, triangular, parallelogram quadrilateral, and regular quadrilateral, honeycombs, diamonds, squares, triangles, parallelograms, circles, or a combination thereof. In some embodiments, the ratio of the thickness of a wall26to the maximal linear extent between faces17and17′ is between 0.01-10:1. A wall thickness ranges from 0.1 mm to 100 mm in such embodiments.

The adhesive layers20,22are formed of either a thermoplastic or curable formulation, a polyurethane or polyurethane prepolymer adhesive, which may be in the form of glue, a moisture cure adhesive, a reactive hot melt adhesive, or a polyurethane resin. As shown inFIG.5, due to the compressive force applied to the adhesive layers20,22between the surface sheet14and the open area core12and the structural skin16and the open area core12, the adhesive20,22is engineered to have an initial viscosity on contact with the face17and the walls26so as partially fill the pores24of the open area core12. The viscosity of the adhesive layers20,22ensures that the adhesive does not excessively run into the pores defined in the open area core before the adhesive attains final strength. Accordingly, the adhesive surface area for adhesion between a surface sheet and structural skin and the open area core is at least 5% more than surface area of the walls at the face. This increased surface area of adhesion reduces delamination of the components of the composite sandwich10and surprisingly allows for the use of thinner surface sheets that do not exhibit bond line read through. As a result of increasing the adhesive surface area coverage from 10 to 50 surface areas percent allows for the comparatively expensive high gloss surface sheet to be reduced in thickness from 1.5 mm to between 1.3 and 0.8 mm while still preventing of bond line read through.

The surface sheet14of the composite sandwich material10is formed from sheet molding compound (SMC), thermoplastic, dicyclopentadiene (DCPD), overmolded polyurethane (PU), or a combination thereof. According to embodiments, the surface sheet14is a high gloss surface sheet having a high gloss surface15. The surface sheet14can include a filler material30to reinforce and/or serve to decrease the weight of the high gloss surface sheet14. The filler material30is any of glass fibers, carbon fibers, natural fibers, hollow or solid glass microspheres, or a combination thereof. The fibers may be oriented or non-oriented. In some inventive embodiments in which SMC forms the high gloss surface, a resin package sold by Continental Structural Plastics, Inc. under the tradenames TCA® and TCA® ULTRA-LITE™ are used herein. Exemplary formulations of which are detailed in U.S. Pat. No. 7,700,670, WO2017/184761, and U.S. Pat. No. 7,524,547B2. It is appreciated that the high gloss sheet routinely includes additives to retain dimensionality. Such additives routinely including glass fiber; carbon fiber; inorganic particulate fillers such as calcium carbonate, talc, and carbon black; glass microspheres; carbon nanotubes; graphene; low profile additives; moisture scavengers; and combinations thereof. Typical thicknesses of the high gloss surface sheet in the present invention range from 0.5 to 5 millimeters (mm) without regard to edges.

As will be understood by a person having ordinary skill in the art, the high gloss surface sheet tends to be a comparatively dense component and an expensive portion to manufacture given the materials used and necessary forming processes to maintain minimal perceptible surface defects suitable for a Class A autobody part. To reduce costs and weight of the composite sandwich panel material10, it is accordingly desirable to reduce the thickness of the high gloss surface sheet14, making it as thin as possible. It will also be understood that as the thickness of the high gloss surface sheet14is decreased the high gloss surface sheet14tends to deform when supported by limited portions of the face17above the open area core12. While result to a large contact surface area of the first adhesive layer20is advantageous, in some inventive embodiments a cloth19is embedded in the first adhesive layer20.

The structural skin16is adhered to the second side of the open area core12by the second adhesive layer22. The structural skin16is formed of a fiber mat having non-oriented, non-woven fibers, unidirectional, or woven fibers, a thermoplastic sheet, or an SMC. The structural skin16provides a robust and durable surface. In some embodiments, the structural skin16terminates against the backside of the surface sheet14to encapsulate the open area core12.

According to certain embodiments, the composite sandwich material10provides sound damping, fire retardancy, thermal insulation, or a combination thereof by placing a sound and/or heat absorbing material within the pores24of the open area core12. According to embodiments, the pores24of the open area core12are at least partially filled with a fill49. The fill illustratively including foam pellets, fire retardant, or a phase change material. Phase change materials operative herein include waxes or an inorganic salt hydrates.

The surface sheet14and the structural skin16are joined together along an edge33A-33D of the composite sandwich material10to form a seal, as shown inFIGS.6A-6D, respectively. In certain embodiments in which all of the edges of the composite sandwich material assembly10are sealed, the open area core12is fully enclosed and moisture is inhibited from entering the interior of the composite sandwich material assembly10. Given that the components of the inventive containment construct112formed of the composite sandwich material assembly10are exposed to natural elements including sun, snow, humidity, and rain, preventing moisture from entering the interior of the composite sandwich material10is important given that freeze thaw cycles of moisture within the part cause expansion and potentially failure of the composite sandwich material10, leading to damage to the vehicle containment construct112. Additionally, in embodiments in which the open area core12is formed of a hydrophilic material such as paper, moisture within the composite sandwich material assembly10would destroy the open are core12and cause the part to fail.

FIGS.6A-6Dshow various embodiments of ways in which the surface sheet14and the structural skin16are joined together to form a sealed edge33A-33D, respectively according to the present disclosure. In some inventive embodiments an elastomeric gasket34is disposed between the surface sheet14and the structural skin16at the33C to make the edge33C more water resistant. It is appreciated that a gasket is readily included in the other edge joinder33A,33B, and33D. The gasket35enhances maintenance of the edge seal over a wider range of use conditions.

As will be understood by one having ordinary skill in the art, to form an edge seal between the surface sheet14and the structural skin16, at least one of the surface sheet14and the structural skin16requires enough material to wrap around the edge of the composite sandwich10. According to embodiments, at least one of the surface sheet14and the structural skin16is provided in dimensions greater than the dimensions of the final composite part such that the material is able to wrap around the final edge composite sandwich10. According to certain embodiments, the at least one of the surface sheet14and the structural skin16is preformed such that it has edges extending generally perpendicularly from the plane of the sheet material.

According to embodiments, excess material is cut from the composite sandwich once the edge seal is formed. As shown inFIG.6A, excess material of the structural skin16has been trimmed from the composite sandwich assembly10by a knife or router that presses against the divot35A that is formed by the surface sheet14. InFIG.6B, the edge33B formed by removing excess material for tool engagement against a shoulder35B of the surface sheet14. InFIG.6C, the edge33C formed by removing excess material for tool engagement against a shoulder35C of the surface sheet14. Also, as shown inFIG.6D, excess material of one or both the surface sheet14and the structural skin16are trimmed with tool pressure against shoulder35D.

As shown inFIG.7, embodiments of an inventive vehicle containment construct112include a conduit system120embedded within the composite sandwich material10of the vehicle component. As shown inFIG.7, the conduit system120is embedded in the open area core12of composite sandwich panel assembly10that forms the vehicle cargo construct112. According to embodiments, the conduit system120comprises tubing or wires that are molded into the open area core12of the composite sandwich10before the vehicle component is formed. According to embodiments, the conduit system120includes electrical wiring, ventilation ducts, or heating elements. Accordingly, embodiments of the containment construct112of the inventive modular utility vehicle100are capable of including features such as speakers, lights, air vents, and defrosting elements for removing ice or snow present on the vehicle cargo construct112. The conduit systems120of various vehicle components are configured to align with one another to form a single connected conduit system throughout the vehicle to connect electrical wiring, ventilation ducts, and/or heating elements of each of an inventive vehicle cargo construct with like electrical wiring, ventilation ducts, and/or heating elements of the vehicle to function.

As described above,FIGS.1-3show a rear perspective view of a modular utility vehicle100according to embodiments of the present disclosure. The modular utility vehicle100includes a plurality of modular panels110formed of the composite sandwich material10described above. The plurality of modular panels110together form a containment construct112that is fixed to the rear portion106of the chassis102and may abut the operator cab108at the front portion of the chassis102. According to embodiments the containment construct112includes a floor assembly114, a wall assembly116, and a roof assembly118, each of the floor assembly114, wall assembly116, and roof assembly begin formed of at least one of the panels of the plurality of modular panels110.

According to embodiments, the floor assembly114includes at least one floor panel110′ of the plurality of modular panels110positioned horizontally along the chassis102. Generally, the floor surface within the interior of the containment construct112is defined by the structural skin16of the composite sandwich material10that forms the floor panel110′. According to embodiments, the floor assembly114is attached to the chassis102using a plurality of fasteners. According to embodiments, the floor panel110′ includes a plurality of hard points90, as shown inFIG.8. The hard points90are configured to be points at which the vehicle cargo construct112is attached to the vehicle frame or chassis102. According to embodiments, the hard points90are through holes defined in the composite sandwich material10that forms the vehicle cargo construct112. According to embodiments, a fastener, such as a bolt94, is inserted through the hard point90and through an opening defined in the vehicle frame102, securing the vehicle containment construct112to the vehicle frame102using a nut96. According to embodiments, the hard points90are formed in mounting recesses93that are formed in the structural skin16surface of the composite sandwich material10, thus allowing the head of the fastener94to be recesses into the mounting recess93so that the head of the fastener94is flush with the surface of the cargo compartment that is defined by the structural skin16of the composite sandwich material10. According to embodiments, the hard points90include a collar92disposed within the through hole that forms the hard point90. The collar92may be inserted into the through hole defined by the composite sandwich panel material10after the through hole is formed in the composite sandwich material10or the collar92may be pre-positioned and the composite sandwich material10formed around the collars92.

According to embodiments, the floor assembly114includes a plurality of tie down points121. The tie down points121are positioned on and formed in the floor panel110′ on the side that is positioned on the interior side of the containment construct112. The tie down points121provide hard points to which equipment may be tied or strapped for secured transport within the modular utility vehicle100. According to embodiments, the floor assembly114includes a track system124. The track system124is formed in the floor panel110′ to allow equipment to be slidably secured into the track system124. That is, equipment with a foot or foot attachment that corresponds to the shape of the track system124, for example a T-shape, may be slidably secured into the track system124such that the equipment is prevented from uncontrollably sliding around the containment construct112, for example when the utility vehicle100is underway, but the track system124allows the associated equipment to be controllable moved within the track system124in the event a user needs to move a piece of equipment within the containment construct112. According to embodiments, the floor assembly114includes an extendable ramp122, which according to embodiments is formed of the same composite sandwich material10as the plurality of modular panels. The extendable ramp122is useful for moving heavy objects into and out of the contained volume defined by the containment construct112of the modular utility vehicle100. The extendable ramp122either slides out from the floor panel110′ on a pair of rails or folds out via the ramp's hinged connection to the floor panel110′. According to embodiments, the extendable ramp122is actuated by any of manual operation or electronic control.

According to embodiments, a bed liner84is positioned on the upper surface of the floor panel110′ of the containment construct112. According to embodiments, the bed liner84is formed of the composite sandwich material10. According to embodiments, the bed liner84is removable from the cargo construct112such that the bed liner84may be removed, easily washed, or replaced, thus protecting the floor panel110′.

According to embodiments, the wall assembly116of the containment construct112of the modular utility vehicle100includes a plurality of wall panels110″ of the plurality of modular panels110. The wall assembly116is positioned perpendicularly to the chassis102and perpendicularly to the floor assembly114. The plurality of wall panels110″ of the wall assembly116may be formed of a single piece of composite sandwich material10or may be formed of several separate panels of composite sandwich material10that are joined together to form the wall assembly116. The wall panels110″ may be joined together using ordinary fasteners or the hard points90as shown inFIG.8. According to embodiments, any of the wall panels110″ are formed of a double wall of composite sandwich material10. In such embodiments, a void may be formed between the two walls of composite sandwich material10. Within such a void, at least one compartment for housing various items is formed. The compartment may have a locking door formed in either one or both of the surrounding walls of composite sandwich panel material10.

According to embodiments, the wall assembly116additionally includes a plurality of wheel wells76each having an interior surface and an exterior surface. Each of the wheel wells76configured to receive a wheel of the vehicle on the side of the exterior surface of the wheel well76and partially surround the wheel of the vehicle. According to embodiments, the plurality of wheel wells76are defined by and are integrally formed with each of the side wall panels110″. Alternatively, the wheel wells76are structures formed separately from the side wall panels110″. Each of the wheel wells76is positioned between one of the side wall panels110″ and the floor panel110′.

According to embodiments, a wall panel110″ of the wall assembly116includes a window56formed therein. The window56is disposed in a through opening62that is defined in the wall panel110″. The through hole62extends from a first exterior surface of the wall panel110″ to an interior surface of the wall panel110″. The window56is formed of a transparent material, such as a transparent resin or glass. According to embodiments, the window56is formed by injection molding. In such embodiments, a transparent resin that forms the window56is injected into a mold, preferably the same mold that is used to form the shape of the wall panel11″. Thus, the panel110″ is capable of being formed as a single unit from a single mold or manufacturing device. This presents significant time and monetary savings for manufacturers.

According to embodiments, the transparent resin of the window56is a thermoplastic resin having high impact resistance and toughness, such as acrylonitrile butadiene styrene (ABS). Additionally, the window56formed by a resin is significantly lighter in weight than a typical glass window, thereby significantly reducing the weight of the vehicle component construct. According to embodiments, the ABS resin includes from 15 to 35% acrylonitrile, 5 to 30% butadiene, and 40 to 60% styrene. Components formed from ABS resin have high impact resistance and toughness, making ABS particularly well suited for forming a vehicle window. The transparent resin can be tuned to improve impact resistance, toughness, and heat resistance. For example, impact resistance can be amplified by increasing the proportions of polybutadiene in relation to styrene and also acrylonitrile, although this causes changes in other properties. Impact resistance does not fall off rapidly at lower temperatures. The transparent resin can be further tuned by modifying the conditions under which the material is processed to the final product. For example, molding at a high temperature improves the gloss and heat resistance of the product whereas the highest impact resistance and strength are obtained by molding at low temperature. Fibers (usually glass fibers) and additives can be mixed in the resin pellets to make the final product strong and raise the maximum operating temperature as high as 80° C. (176° F.). According to embodiments, particles are added to the transparent resin such that the window56is tinted to provide UV protection within the vehicle. According to embodiments, additives are provided in the transparent resin to increase the window's56ability to withstand the harmful effects of ultraviolet radiation.

According to embodiments, the window56is formed of glass. In such embodiments, a glass window56may be positioned in such a way that the wall panel110″ is molded around the glass window56. Alternatively, the glass window56is bonded to a lip that surrounds the through opening62formed in the wall panel110″.

According to embodiments, the window56, formed of either glass or a transparent resin, includes window defroster elements that are molded into the window56. According to embodiments, the window defroster elements are a plurality of wires that are configured to be electrically heated such that any frost, fog, or ice that forms on the window56can be removed by the heating of the wires. According to embodiments, the window defroster elements of the window56include a connector that is positioned outside of the window56. The connector is configured to be connected with a corresponding connector positioned on the wall panel110″.

According to embodiments, a wall panel110″ or a door panel110′″ having a window56includes a wiper blade72pivotably mounted to the exterior surface of the panel110. The wiper blade72is configured to engage with the window56to wipe liquid, debris, and dirt from the surface of the window56. According to embodiments, the wiper blade72is attached to the panel110after the panel110is formed. Accordingly, attaching the wiper blade72may include drilling an attachment hole into the exterior surface of the panel110and attaching the wiper blade72thereto with a fastener.

According to embodiments, a wall panel110″ of the wall assembly116includes at least one accessory mounting point126and/or an accessory track128positioned on an interior surface thereof, that is the surface of the wall assembly116that is positioned within the containment construct112. Such mounting points126or tracks128may be embedded into the open areas core12of the composite sandwich material10that forms the wall panel110″ in order to provide strength to the mounting points126or tracks128. The exact nature and position of the mounting points126or tracks128are variable and configurable to suit the needs of the user of the particular modular utility vehicle100. For example, the mounting points126or tracks128may be configured to hold various tools, equipment of supplies based on the necessary uses of each modular utility vehicle100.

According to embodiments the wall assembly116of the containment construct112of the modular utility vehicle100includes at least one door panel110′″ of the plurality of modular panels110. According to embodiments, the door panel110′″ is a tailgate, liftgate, hatch door, or pivoting door that is attached to the wall assembly116by a plurality of hinges68. According to embodiments, the door panel110′″ is or sliding door that moves relative to the wall assembly116on a sliding door track system. According to embodiments, the hinges68are attached to the interior surface of the door panel110′″ of the wall assembly116. According to embodiments, the door panel110′″ includes a plurality of cutouts that correspond in shape and desired location to the hinges68. Such cutouts are formed in the composite sandwich material10that forms the door panel110′″ by either cutting the cutouts out from the material of the door panel110′″ or by forming the cutouts in the door panel110′″ by molding when the door panel110′″ is formed. According to embodiments, the cutouts are positioned along a side outer edge of the door panel110″″, as shown inFIGS.1-3. In such a case, the door panel110′″ pivots about the hinges68to move an open position. According to embodiments, the hinges68are positioned at a lower edge of the door panel110′″ such that when the door panel110′″ pivots to the open position, the door panel folds out into a ramp that may be used to move users and items into and out of the containment construct112of the modular utility vehicle100. According to embodiments, the door panel110′″ includes a safety cable51that is configured to be attached between the door panel110′″ and another portion of the wall assembly116.

According to embodiments, the safety cable51is embedded in the door panel110′″ at a first end of the safety cable51and is attachable at the opposite end of the safety cable51to the frame of the wall assembly116. The safety cable51thus connects the door panel110′″ to another portion of the modular utility vehicle100at a point in addition to the hinges68. Thus, in the event of a crash or failure of the hinges68, the door panel110′″ remains connected to the vehicle.

According to embodiments, the door panel110′″ includes a locking mechanism64. The locking mechanism64is positioned on the interior surface of the door panel110′″ that is defined by the structural skin16of the composite sandwich panel material10. According to embodiments, the locking mechanism is attached to the door panel110′″ after the door panel110′″ is shaped and formed, which may include cutting an opening in the interior surface of the door panel110′″ that corresponds to the shape and desired location of the locking mechanism64. The locking mechanism64may include a latch and a catch that are configured to cooperate with one another in order to hold the door panel110′″ in a closed position relative to the wall assembly116.

According to embodiments, the door panel110′″ includes a handle66. The handle66is positioned on the exterior surface of the door panel110′″ that is defined by the high gloss surface sheet14of the composite sandwich material10. According to embodiments, the handle66is attached to the door panel110′″ after the door panel110′″ is shaped and formed, which may include drilling attachment holes in the exterior surface of the frame that corresponds to the shape and desired location of the handle66.

According to embodiments, the roof assembly118of the containment construct112of the modular utility vehicle100is formed of at least one roof panel110″″ of the plurality of modular panels110. The roof assembly110″″ is positioned horizontally above the chassis102. According to embodiments, the roof assembly118is attached to the wall assembly116using a plurality of fasteners. The fasteners may be ordinary fasteners or may utilize hard points90as described with reference toFIG.8. According to embodiments, the roof panel110″″ includes a refrigeration unit130that is configured to maintain the containment construct112at a temperature suitable for frozen or refrigerated goods. According to embodiments, the roof assembly118is configured to vertically expand such that uses of the modular utility vehicle100are not limited by the height of the containment construct112.

According to embodiments, the lower surface of the floor panel110′ is defined by the surface sheet14of the composite sandwich material10and the oppositely opposed upper surface of said floor panel110′ is defined by the structural skin16of the composite sandwich panel material10. According to embodiments, the exterior surface of each of the wall panels110″ or door panels110′″ is defined by the surface sheet14of the composite sandwich material10and the oppositely opposed interior surface of each of the side wall panels110″ or door panels110′″ is defined by the structural skin16of the composite sandwich material10. As noted above, in embodiments surface sheet14of the composite sandwich material10is a high gloss surface sheet with a high gloss finish value of 15 with minimal perceptible surface defects suitable for a Class A autobody part. Accordingly, in some embodiments the exterior surface of each of the wall panels110″ or door panels110′″ is a high gloss surface sheet14.

According to embodiments, the upper surface of the floor panel110′ and the interior surface of each of the wall panels110″ or door panels110′″ define a cargo compartment within the vehicle cargo construct112. Given that these surfaces are defined by the structural skin16of the composite sandwich10, these surfaces that define the cargo compartment are high strength, robust, and resistant to scratches, punctures, and other damage.

According to embodiments, the panels110that form the containment construct112are integrally formed of a single piece of composite sandwich material10or are each formed of a separate piece of composite sandwich material10. Accordingly, the vehicle containment construct112is a single unitary construct that is configured to be attached to a vehicle chassis according to some embodiments. Alternatively, the vehicle containment construct112is formed a several separate pieces that are configured to be joined together and to a vehicle chassis. In instances in which the vehicle containment construct112is formed of a single piece of composite sandwich material10, the containment construct112is formed by folding the wall panels110″ up from the floor panel110′. According to embodiments, the folding includes crushing portions of the composite sandwich material10, particularly the open area core12along the fold lines.

According to embodiments, the vehicle containment construct112includes a plurality of break lines88or corrugations formed in the panels110. Such break lines88provide a predetermined crumple path in the event of an impact so that the composite sandwich material10of each part crumples and absorbs impact energy. According to embodiments, the break lines88are formed by crushing the open area core12of the composite sandwich material10in pre-determined locations.

Patent documents and publications mentioned in the specification are indicative of the levels of those skilled in the art to which the invention pertains. These documents and publications are incorporated herein by reference to the same extent as if each individual document or publication was specifically and individually incorporated herein by reference.