Abstract:
A multi-purpose, collapsible portable cart, for use in camping, hunting and other outdoors activities carries medical rescue carts, canoes, small boats, game, or hauled cargo by hand. The portable cart can be converted to a various uses and the portable cart can be folded down and transported within a backpack, hand carried bag, canoe or boat. It transports injured persons or cargo over long, rough terrain and it can broken down into a carrying position, by hand or by back. Its width can be varied to accommodate cargo of varying widths. Two or four wheeled versions can be assembled with axles and wheels. The cart has optional removable clamps for clamping a conventional transportable carrier, such as a stretcher or stokes-type rescue carrier bed, thereto. The objects being carried can be held by clamps, by fasteners, or through the use of insertions with longitudinally extending channels. An optional pivotable kickstand and/or tie rods can stabilize the cart in a position of rest. It is collapsible, so that it can be disassembled and carried, and then reassembled at another destination along a wilderness journey.

Description:
RELATED APPLICATIONS  
       [0001]    This application in part disclosed and claims subject matter disclosed in my earlier filed provisional patent applications, Serial No. 60/233,138 filed Sep. 18, 2000 and No. 60/246,014 filed Nov. 6, 2000 which both disclose in part subject matter disclosed in my earlier filed patent applications filed under Ser. No. 09/226,838 filed Jan. 7, 1999, Ser. No. 09/479,344 filed Jan. 7, 2000 and Ser. No. 09/745,116 filed Dec. 21, 2000. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to a multiple-purpose collapsible portable cart, for use in camping, hunting, search and rescue, and other outdoors activities. The cart can be easily assembled in a number of uses, and disassembled for easy transporting of the cart in a backpack or hand-carried bag.  
         BACKGROUND OF THE INVENTION  
         [0003]    Various single use carts exist for carrying canoes and small boats by hand. Other outdoors-oriented carts exist for carrying game. In addition, wheelbarrows and small carts are used for transporting gear at outdoors locations. However, none of the existing carts can be converted to a versatile portable cart which can interchangeably function as a rescue cart with a carrier for injured persons, as a portable canoe or boat cart which can be folded down and transported within the canoe or boat, as a game cart for transporting game over long, rough terrain, or as a gear cart, all of which can broken down into a carrying position, by hand or by back.  
         OBJECTS OF THE INVENTION  
         [0004]    It is therefore an object of the present invention to provide a versatile multi-purpose cart, which is quickly assembled or disassembled.  
           [0005]    It is also an object to provide a multi-purpose cart, which quickly converts from one use to another.  
           [0006]    It is further an object to provide a cart which as a stable, flat platform for supporting cooking devices, machinery, camera tripods and the like.  
           [0007]    It is yet another object to provide a cart, which is stable during transport over rough terrain.  
           [0008]    It is yet another object to provide a portable collapsible cart with minimal fasteners.  
           [0009]    It is yet another object to provide a portable collapsible cart, which can be stabilized in a position of rest.  
           [0010]    It is also an object of the present invention to provide a universally adaptable carrier cart.  
           [0011]    It is yet another object of the present invention to provide a cart for carrying medical rescue stretchers, canoes and small boats by hand.  
           [0012]    It is yet another object to provide a portable search and rescue cart adapted to carry a stretcher or other carrier for an injured person.  
           [0013]    It is also an object of the present invention to provide an outdoors-oriented cart for carrying game or injured parties.  
           [0014]    It is yet another object of the present invention to provide a small cart with a well for transporting gear at outdoor locations.  
           [0015]    It is further an object to provide a collapsible, portable cart, which can be assembled with minimal fasteners.  
           [0016]    It is also an object of the present invention to provide a versatile portable cart which can interchangeably function as a portable canoe or boat cart which can be folded down and transported within the canoe or boat, as a rescue cart for injured persons, as a game cart for transporting game over long, rough terrain, or as a gear cart, all of which can be broken down into a carrying position, by hand or by back.  
           [0017]    It is yet another object to provide a portable cart which is either backpackable or which can be carried by hand.  
           [0018]    It is yet another object to provide a carrier for transporting military equipment and ordnance.  
           [0019]    It is yet another object to provide a cart-hauling clamp for pulling the portable cart behind a bicycle while resisting tipping over of the cart during directional change of the cart-hauling bicycle.  
           [0020]    It is yet another object to provide a portable cart which can be used as a wheeled cart on terrain or as a ski cart on snow.  
           [0021]    It is also an object of the present invention to improve over the disadvantages of the prior art.  
         SUMMARY OF THE INVENTION  
         [0022]    In keeping with these objects and others, which may be apparent, the present invention relates to a convertible, multi-purpose portable cart, for use in camping, hunting, search and rescue operations and other outdoors activities, such as for carrying canoes and small boats by hand. It may also carry game, injured parties or be used for transporting gear at outdoors locations. It is a versatile portable cart which can interchangeably function as a medical rescue carrier, cargo carrier, portable canoe or boat cart, which can be assembled with interfitting parts and with minimal fasteners. It can be folded down and transported within the canoe or boat, as a carry cart for transporting game or injured parties over long, rough terrain or snow, or as a gear cart, all of which can be broken down into a carrying position, by hand or by back.  
           [0023]    The cart is moved by manual pushing or pulling force applied to activate vehicle movement actuators, such as wheels upon terrain or skis upon snow or ice, wherein upon the exertion of force the wheels or skis cause forward or rearward movement of the portable cart.  
           [0024]    The cart is easily assembled or disassembled by connecting its parts together, or optionally assembled from a pre-set storage configuration in a carry pack to an assembled structure.  
           [0025]    The cart easily changes from one use to the other. For example, in one embodiment, a hollow cargo well may contain a second loose layer, which turns into a rescue stretcher when the second layer becomes taut when zipped up from a loose, relaxed state within the cargo well to a taut rescue stretcher for carrying injured persons thereon.  
           [0026]    In an alternate rescue embodiment, clamps can be provided on shortened horizontal support members to hold medical rescue stretcher rails, and optional handles or pivotable kickstands can be attached by further clamps to the stretcher rails.  
           [0027]    In military applications, the height of the vertical struts can be lowered to keep the injured person on the stretcher close to the ground, to avoid visible detection.  
           [0028]    The portable cart is preferably under thirty (30) pounds, preferably twenty two (22) to twenty eight (28) pounds, so that it can be carried by hand or within a backpack over rough terrain. It is collapsible, so that it can be disassembled and carried in a canoe or small boat, and then reassembled with minimal assembly steps and parts, at another destination along the canoe or boat&#39;s journey.  
           [0029]    To prevent flat tires, its wheels are preferably solid core tires, which cannot get flat, with stainless steel bearings, over which the wheels rotate. A typical wheel has two press fit bearings adjacent to an integrally molded hub. While the typical wheel is about 2-3 inches wide, for transporting cargo or game on sand or granular terrain, the wheels may be wider, such as 4-6 inches in width.  
           [0030]    For maneuverability in snow-filled winter scenes, optional ski members, including skis, are attached to vertical braces having a length corresponding to the radius of the cart&#39;s wheels. The vertical ski braces are attached to the vertical struts where the wheel axles attach.  
           [0031]    For hardiness, the material of the structural frame components is preferably a lightweight but resilient and strong material, such as, for example, 60-61 T6 fully anodized aluminum, or stainless steel. In a substantially pre-assembled optional embodiment, in a storage position within a carry bag, the vertical struts are connected to horizontal supports, which are further engaged with rails to hold a cargo well or rescue stretcher. Pivoting of the horizontal supports about each respective longitudinal axis to a position of rest biases the resiliently engaged rails to return to their natural position of use when released from the storage position.  
           [0032]    These pivotable support and strut assemblies can be further strengthened by optional V-shaped braces, which are positioned where each vertical strut meets each corresponding horizontal support member.  
           [0033]    The portable cart can hold up to 500 pounds, and for manual pulling easily pulls 300 pounds. The portable cart is durable to carry heavy weight over rough terrain, such as rock-strewn dirt trails or sloping riverbank surfaces.  
           [0034]    To carry a canoe or boat, two horizontal load supports optionally include support cushions upon which the canoe or boat rests. The position of the horizontal load supports can be varied to accommodate various widths of the canoe or boat.  
           [0035]    To function as a game or rescue cart, the frame, such as a pair of U-shaped rails which are joined end to end, is provided upon the horizontal load supports to form a rounded rectangular frame, over which a taunt, but slightly stretchable, bed of fabric is placed, such as canvas or other flexible material, i.e., plastic or netting. The bed includes sewn loops through which portions of the U-shaped rails of the frame are inserted. Other fabric fasteners such as clips, zippers or eyelets can be also used.  
           [0036]    In an alternate embodiment, the boat support cushions are removable from the horizontal load supports and are replaced by a two-piece clamp, which attaches by at least one fastener, such as a pair of screws, to the horizontal load supports of the cart. Conventional stretchers or personal rescue carriers, such as Stokes-type baskets, are clamped to the cart within the clamps on each respective horizontal load support. In this embodiment, the boat support cushions are attached to a thin plate, such as of ⅛ inch aluminum or otherwise, which has at least one fastener such as a pair of threaded studs, insertable with the respective hole or holes in the horizontal load supports, so that the boat support cushions can be removed and replaced by the stretcher-bearing clamps.  
           [0037]    To function as a wagon cart with a well for carrying gear, a hollow fabric well, such as of canvas, is draped between said horizontal load members and over and around the front and rear U-shaped brackets. A cover may be provided to cover the gear therein. The well and cover can also be made of other suitable flexible materials, such as plastic, netting or canvas. An optional removable hard bottom substrate floor layer may be provided within the cargo well. While this floor layer may be of any hard material, materials such as lightweight aluminum, wood or marine polymer plastics are preferred.  
           [0038]    Furthermore, the cargo cart may have an optional handle from which may be draped a further optional accessory cargo bag. In the stretcher embodiment, where the upper layer is fastened taut, the handle may have a removable headrest pillow.  
           [0039]    Kickstands may be optionally provided to stabilize the portable cart during rest or during loading of contents thereon.  
           [0040]    In yet another embodiment, an anti-tipping bicycle attachment is provided to attach the cart to a bicycle while preventing the cart from turning over during transportation.  
           [0041]    In one embodiment, the cart has two wheels for cargoes weighing from 300-500 pounds. However, for heavier loads, such as for 600-1,000 pounds, an optional double axle version includes two pairs of overlapping wheels for heavier cargo. In this embodiment, the portable cart uses four wheels in the overlapped configuration, with an optional hard molded canister. In this overlapping, wheeled version, a long axle attaches a pair of front wheels and a short axle attaches a pair of rear wheels through the respective vertical supports, although the length of the axles can be reversed. Using four wheels doubles the carrying capacity of the cart, and the overlapped positioning of the pairs of wheels maintains a short wheelbase for compactness, for maneuverability and for climbing slopes or ledges.  
           [0042]    In the four-wheeled embodiment, double parallel rails may be provided for additional structural strength. The overlapping, dual axle, four-wheel version gives the user extra pivot points on rough terrain. For example, pushing down upon the optional handle enables the user to lift the further away distal wheels off the ground. Furthermore, pulling upon the handle enables the user to lift the nearer, proximal wheels off the ground.  
           [0043]    The accessory which is placed upon the vertical supports of either the two wheeled or four wheeled carts, such as the rescue stretcher, the boat cushion, the cargo cart, etc., can be attached permanently or by fasteners to each horizontal load support member of the portable cart. However, in an alternate embodiment, the horizontal supports have longitudinally extending channels to slide the accessories in on top of the horizontal supports. Furthermore, the accessory, such as a railed rescue stretcher, can be carried by a clamp which itself is attached to the horizontal support by insertion in such a channel.  
           [0044]    This clamp upon each horizontal support member may be a one piece clamp with a full width top section and short end pieces which mate with and slip into a T-shaped slot channel of the horizontal support member. Alternatively, the clamp may have a full width bottom member which mates with and slides into a T-slot of the horizontal support. In yet another embodiment, two short identical clamp members are inserted into the T-slots of the horizontal member at the two ends. Moreover, the clamping sections can have spring-like gripping action to be retained upon tubular members, such as medical rescue stretcher rails, or the clamps can use fasteners such as fasteners, such as thumbscrews or ball plungers for retention.  
           [0045]    In yet another embodiment, a covered canister can be held in place over the rails of the frame of the cart, in a stable position, by virtue of its weight being held in place upon the rails of the cart, wherein a concave, downward facing channel engages the linear, upper convex support surface of each rail.  
           [0046]    Furthermore, the cart of the present invention can be disassembled and broken down for hand held or backpack transport and it can easily be assembled for its varied uses. Moreover, when a boat or canoe is carried, the cart has a precision balance feature that rotates the wheels to maintain the cart in a horizontal stable position. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0047]    The present invention can best be described in connection with the accompanying drawings, in which:  
         [0048]    [0048]FIG. 1 is an exploded perspective view of the components of the basic cart embodiment broken down for transport within and on the storage backpack;  
         [0049]    [0049]FIG. 2 is a perspective view of the backpack on a user, with the cart contained therein;  
         [0050]    [0050]FIG. 3 is an exploded inverted perspective view of the basic cart embodiment components, disassembled from their original transport configuration;  
         [0051]    [0051]FIG. 3A is a perspective view of an alternate simplified embodiment where the vertical strut is permanently attached to a horizontal member in a “T” configuration;  
         [0052]    [0052]FIG. 3B is a perspective view of an embodiment where the horizontal support is permanently affixed to the vertical strut by welding or other means;  
         [0053]    [0053]FIG. 3C is an alternate embodiment where the vertical strut fits within a hole in the horizontal support and is fastened by a fastener.  
         [0054]    [0054]FIG. 4 is a perspective view of the assembled boat cart;  
         [0055]    [0055]FIG. 5 is a perspective view of the assembled cart with a boat fastened for transport;  
         [0056]    [0056]FIG. 6 is an exploded perspective view, inverted, of the components required to assemble the boat cart;  
         [0057]    [0057]FIG. 7 is an exploded perspective of a typical wheel, showing two press fit bearings adjacent an integrally molded hub;  
         [0058]    [0058]FIG. 8 is a perspective view of an axle-locking member, installed on the assembled axle;  
         [0059]    [0059]FIG. 9 is a sectional elevation view, taken through lines  9 - 9  of FIG. 8, showing the locking member compressing and locking the axle joint;  
         [0060]    [0060]FIG. 10 is a diagrammatic side elevation view of the boat cart in its resting position, with a boat hull contacting the raised edge;  
         [0061]    [0061]FIG. 11 is a diagrammatic side elevation view of the boat cart with the boat hull positioned and fully installed, illustrating the precision balancing feature of the cart;  
         [0062]    [0062]FIG. 12 is a perspective view of the assembled alternate embodiment cart, for hunting/gaming applications;  
         [0063]    [0063]FIG. 13 is an exploded perspective view of the inverted gaming cart, illustrating the framework fastening method;  
         [0064]    [0064]FIG. 14 is an exploded perspective view, inverted, of the gaming cart, illustrating the attachment of the stretcher canvas material to the framework components;  
         [0065]    [0065]FIG. 15 is an exploded perspective view of the attachment of the handlebar component to the locking receptacles on the framework;  
         [0066]    [0066]FIG. 16 is a sectional elevation view, taken through lines  16 - 16  of FIG. 15, showing the locking receptacles acting on the installed leg of the handlebar;  
         [0067]    [0067]FIG. 17 is a perspective view of the gaming cart, with a deer fastened for transport;  
         [0068]    [0068]FIG. 18 is a perspective view of a further embodiment, a cart for transporting cargo, equipped with optional wide tires and axle for use on sand or granular terrain;  
         [0069]    [0069]FIG. 19 is a perspective view of a fully loaded cargo cart, with the cover material partially cutaway to reveal its contents;  
         [0070]    [0070]FIG. 20 is an exploded perspective view, inverted, of the cargo cart, illustrating the attachment of the canvas material to the framework components;  
         [0071]    [0071]FIG. 21 is another exploded perspective detail view of the components for a stretcher-hauling clamp of an alternate embodiment for a search and rescue cart;  
         [0072]    [0072]FIG. 22 is a perspective view of the clamp embodiment shown in FIG. 21, showing the sliding action of the clamp therein, for quick removal of the stretcher therefrom;  
         [0073]    [0073]FIG. 23 is a perspective view of the portable cart of the present invention, showing the clamp as in FIGS. 21 and 22 carrying a rescue stretcher;  
         [0074]    [0074]FIG. 24 is a perspective view of the portable cart carrying a Stokes-type personal rescue carrier;  
         [0075]    [0075]FIG. 25 is an exploded view of components of a further alternate embodiment for a support for removal of a boat support cushion therefrom;  
         [0076]    [0076]FIG. 26 is a perspective view of an alternate embodiment for a hunting cart with an accessory racking system for transport of hunting gear, such as a tree stand chair, archery implements and firearms thereon;  
         [0077]    [0077]FIG. 27 is an exploded detail view of a quick release clamp for rail fastening to the cart shown in FIG. 26;  
         [0078]    [0078]FIG. 28 is an assembled elevational view of the clamp of FIG. 27 attached to a rail;  
         [0079]    [0079]FIG. 29 is an exploded perspective view of a typical clamp for gear support for the cart as in FIG. 26;  
         [0080]    [0080]FIG. 30 is a perspective view of an anti-tipping attachment for connecting a bicycle to the portable cart of the present invention;  
         [0081]    [0081]FIG. 31 is an exploded perspective view of the components of FIG. 30;  
         [0082]    [0082]FIG. 32 is a side elevational view of an alternate embodiment of the portable cart of this invention with four wheels, shown with a covered cargo-hauling bin;  
         [0083]    [0083]FIG. 32A is a top plan view of the cover for a bin used with the cart as in FIG. 32;  
         [0084]    [0084]FIG. 32B is a top plan view of the bin used with the cart as in FIG. 32;  
         [0085]    [0085]FIG. 32C is an exploded view of the cover and bin as in FIG. 32;  
         [0086]    [0086]FIG. 32D is a side elevational view of the cover and bin as in FIG. 32;  
         [0087]    [0087]FIG. 32E is a front elevational view of the cover and bin as in FIG. 32;  
         [0088]    [0088]FIG. 32F is a front cross-sectional view thereof, taken along lines “ 32 F- 32 F” of FIG. 32D;  
         [0089]    [0089]FIG. 32G is an exploded perspective view thereof;  
         [0090]    [0090]FIG. 33 is a perspective view of one embodiment for an assembled frame of a portable cart with four wheels;  
         [0091]    [0091]FIG. 33A is a bottom perspective view of the chassis and wheel portions thereof;  
         [0092]    [0092]FIG. 34 is a perspective view of an alternate embodiment of a channeled horizontal load support member with an integral T-slot;  
         [0093]    [0093]FIG. 35 is a perspective view of the channeled horizontal load support member as in FIG. 34, shown with an extruded support cushion installed in a T-slot;  
         [0094]    [0094]FIG. 36 is a perspective view of the embodiment for an assembled cart with four wheels further incorporating horizontal support members with a T-slot;  
         [0095]    [0095]FIG. 37 is a perspective view of a horizontal support member with a clamp member having two short T-slot engaging members and a full-length top section;  
         [0096]    [0096]FIG. 38 is a perspective view of a horizontal support member with a clamp member having a full-length T-slot engaging bottom member and two short clamping top members;  
         [0097]    [0097]FIG. 39 is a perspective view of a horizontal support member with two short identical clamping members installed in the T-slots at the extreme ends;  
         [0098]    [0098]FIG. 40 is a side elevational view of an alternate embodiment for a rescue carrier cart with shortened horizontal supports and with a pivotable kickstand;  
         [0099]    [0099]FIG. 41 is a front elevational view of the kickstand portion of the rescue carrier cart as in FIG. 40;  
         [0100]    [0100]FIG. 42 is a side elevational view of the rescue carrier cart as in FIG. 40, shown with the kickstand pivoted in a transportable position of rest;  
         [0101]    [0101]FIG. 43 is a side elevational view of a low profile military rescue carrier cart, shown with a handle;  
         [0102]    [0102]FIG. 44 is a front elevational view of the handle as in FIG. 43;  
         [0103]    [0103]FIG. 45 is a side elevational view of an alternate embodiment for a four wheeled rescue carrier cart, shown with stretcher rails and with stabilizing tie rods, for use as a temporary stationary medical gurney;  
         [0104]    [0104]FIG. 46 is a top plan view thereof; shown without the stretcher rails;  
         [0105]    [0105]FIGS. 47, 47A,  47 B,  48  and  49  show respective isometric, left side, top, front and right side views of the clamp used in the embodiments shown in FIGS.  40 - 46 ;  
         [0106]    [0106]FIG. 50 is an isometric view of a half piece thereof, shown with spring pins;  
         [0107]    [0107]FIG. 51 is an isometric perspective view of a further embodiment for a disassembled, single axle cart, stored in a carry bag;  
         [0108]    [0108]FIG. 51A is a further perspective view thereof;  
         [0109]    [0109]FIG. 52 is an exploded perspective view of the cart as in FIG. 51, shown during assembly, wherein arrows indicate directional movement of rotation about the axis of the rails shown therein;  
         [0110]    [0110]FIG. 52A is a perspective view thereof showing one wheel in place upon an axle;  
         [0111]    [0111]FIG. 53 is a close-up cutaway view of the spring stop member regulating outward movement of the optional rails of the cart of the present invention from a storage position to a position of use;  
         [0112]    [0112]FIG. 54 is an overall perspective view in partial cutaway of the cart showing the wagon portion in its cargo-carrying configuration;  
         [0113]    [0113]FIG. 55 is an overall perspective view of the cart of FIG. 54, shown in its rescue stretcher configuration;  
         [0114]    [0114]FIG. 56 shows a detail view of an optional ski attachment instead of wheels, for use in snow and winter environments;  
         [0115]    [0115]FIG. 57 shows a detail view of an optional platform base for supporting objects thereon;  
         [0116]    [0116]FIG. 58 is a perspective view of portable cart frame configured as a multi-victim stretcher;  
         [0117]    [0117]FIG. 59 is a perspective view of multi-victim stretcher using single fabric top surface cover;  
         [0118]    [0118]FIG. 60 is a perspective view of multi-victim cart frame reconfigured to accept separate stretchers;  
         [0119]    [0119]FIG. 61 is a perspective view of multi-victim stretcher using separate stretchers;  
         [0120]    [0120]FIG. 62 is an end view of wheel subassembly attachment mechanism in engaged position;  
         [0121]    [0121]FIG. 63 is an end view of wheel subassembly attachment mechanism in disengaged position;  
         [0122]    [0122]FIG. 64 is an end view of attachment clamp for tubular overhead bar;  
         [0123]    [0123]FIG. 65 is a perspective view of portable cart frame configured as an operating room table/gurney;  
         [0124]    [0124]FIG. 66 is a perspective view of operating room table/gurney;  
         [0125]    [0125]FIG. 67 is an end view of wheel brake mechanism in applied position;  
         [0126]    [0126]FIG. 68 is an end view of wheel brake in an off position;  
         [0127]    [0127]FIG. 69 is an end view of side rail adjustable clamp; and,  
         [0128]    [0128]FIG. 70 is a perspective view of adjustable clamp assembly.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0129]    As shown in the drawing FIGS.  1 - 70 , the present invention is directed to foldable cart  1 , for carrying a boat, such as a canoe, which can also function as a game cart or a wagon for carrying gear in outdoor field applications.  
         [0130]    [0130]FIG. 1 shows cart  1  in a disassembled storage position with a pair of horizontal load support members  10  laid parallel adjacent to each other, supporting wheels  30  thereon. Wheels  30  are secured in place by a transverse connecting rod  31  through wheel hubs  30   a  and by one or more load securing straps  50 . Disassembled storage cart  1  is inserted within carry bag  120 , which includes ledge  121  and fabric loops  122  for holding bracket members  60 ,  70  and handle  80  outside of carry bag  120 .  
         [0131]    To transport portable cart  1  by hand carry straps  124  are attached to carry bag  120 . Conversely as shown in FIG. 2, to transport portable cart  1  upon the back of a user, carry straps  124  are attached to carry bag  120 , which supports portable cart  1  in a weight bearing manner, or else horizontal support members  10  are inverted to support portable cart  1  in a weight bearing manner, and carry bag  120  covers portable cart  1  in a non-weight bearing manner.  
         [0132]    To be disassembled in a carry position, U-shaped bracket rails  60 ,  70 , wheels  30  and axle members  32  are inversely attached to horizontal load supports  10  to comprise a folded manually transportable cart.  
         [0133]    As shown in the exploded view of FIG. 3, in the storage position, in a preferred embodiment, cart  1  includes a pair of parallel, spaced apart inverted horizontal load support members  10 . Support members  10  each have a front-end  10   a  and a rear end  10   b . The front and rear ends  10   a ,  10   b  each have at least one axially placed receptacle aperture  12  extending longitudinally within each load support member  10 , for holding structural components therethrough in a storage position, such as axle members  32  for wheels  30 . In this storage position, axle members  32  are also inserted within aperture of  33  of axle connector  34 .  
         [0134]    [0134]FIG. 3 also shows horizontal load support members  10  having preferably a generally upside down U-shaped configuration when viewed in cross-section, wherein a generally flat member  10   c  has downwardly extending flanges  10   d ,  10   e  including one or more linearly extending slots  10   f  for insertion of holding straps  50  therein.  
         [0135]    Although apertures  12  are shown in the drawings, it is contemplated that other configurations may be applicable to horizontal load support members  10 , so long as other members, such as rails  60 ,  70  and so forth, may be attached thereto by fasteners, preferably in an axis parallel to the axis of horizontal support members  10 .  
         [0136]    While size may vary, support member  10  is preferably sixteen (16) inches long and two and a quarter (2.25) inches wide. Each flange  10   d ,  10   e  extends down about one (1) inch from flat member  10   c . Slots  10   f  are preferably 2.125 inches wide and 0.1875 inches high, to accommodate straps  50 , such as, for example, standard 2-inch wide fabric straps.  
         [0137]    [0137]FIG. 3 also shows vertical struts  20  optionally having at least one small hole  22 , such as kickstand receptacle aperture  22 , for insertion of optional kickstand  40  therein.  
         [0138]    [0138]FIG. 3 also shows horizontal load support members  10  being respectively demountably attached to a pair of vertical struts  20 , having apertures  21  and  22 . In one embodiment, horizontal load support members  10  can be demountably attached to vertical struts  20 , but in an alternate embodiment they can be permanently affixed to each other, such as in the alternate embodiments shown in FIGS. 3A and 3B.  
         [0139]    Moreover, while preferably horizontal struts are U-shaped, as in FIG. 3, in alternate embodiments other configurations can be used, as long as vertical strut  20  can be attached to horizontal support member  10 .  
         [0140]    For example, in FIG. 3A vertical strut  20 ′ is in a unified T-shaped member with horizontal support member  10 ′. In FIG. 3B, vertical struts  20 ′ and horizontal support members  10 ′ are attached by weldment  20 ″. In FIG. 3C, vertical strut  20 ′ is inserted in hole  10 ″ of horizontal support member  10 ′, and attached by fastener  10 ′″, such as a screw or other fastener. In these alternate embodiments shown in FIGS. 3A, 3B or  3 C, horizontal load support members  10 ′ may be solid in cross sectional configuration. One such configuration shown in FIGS. 3A, 3B and  3 C is that of a parallelepiped, namely a solid form, all of whose sides are parallelograms, such as rectangles, and whose opposite sides are parallel to one another.  
         [0141]    In another embodiment vertical strut  20  may be adjustable in length with a sleeve containing a telescopic shaft (not shown) and with a spring urging the shaft in and out of the sleeve, with a lock provided.  
         [0142]    Kickstand  40  is shown deployed in FIG. 4. Kickstand  40  is secured in place by a fastener, such as nylon set screw  37 . Setscrews  37  also hold axle members  32  in the storage position through vertical struts  20 .  
         [0143]    Vertical struts  20  are preferably made from 1 ½×2-inch solid bar stock anodized aluminum, or stainless steel. Vertical struts  20  are preferably about 10.25 inches long, 2 inches wide and 1 ½ inches in depth.  
         [0144]    Also shown in FIG. 3, the plurality of optional larger holes  21 , such as holes, which are 0.765 or 1.625 inches in diameter, are located on a front side of vertical strut  20 . Smaller hole  22  on the bottom accommodates kickstand  40 , which is preferably a hollow aluminum tube of 0.75-inch diameter and 16 inches in length.  
         [0145]    Optional larger holes  21  within vertical strut  20  are provided for weight reduction of portable cart  1 .  
         [0146]    On a side  23  transverse to the front  24  of each vertical strut  20 , at a lower portion  20   a  thereof, is provided a further hole  25  of about 1-inch in diameter for insertion of each axle member  32  therethrough. Hole  25  has a permanently affixed, bushing  26  therein, such as a PVC (polyvinyl chloride) bushing, to prevent wear and tear of each aluminum axle member  32  by the aluminum surface of hole  25 .  
         [0147]    As also shown in FIGS. 3, 4 and  6 , each wheel  30  is demountably attached at an end, respectively, to a pair of axle members  32 , with axle members  32  extending inwardly from and demountably attached to lower portion  20   a  of said respective vertical struts  20 , wherein axle members  32  are in a transverse relationship to horizontal load support members  10 . Fasteners,  36 , such as cotter pins, hold each wheel  30  upon each axle  32 .  
         [0148]    Each axle member  32  is received within each hole  25 , of each lower portion  20   a  of each vertical strut  20 . A compression groove  27  exists from the underside of vertical strut  20  to hole  25  and continues to further through hole  27   a , providing for compression of lower portion  20   a  of vertical strut  20 .  
         [0149]    To accommodate narrow or wider cargo, such as watercraft of varying widths, the distance between vertical struts  20  can be varied along the axle length by loosening and tightening the tightening member  28  and moving vertical struts  20  laterally apart or towards each other along axle members  32 .  
         [0150]    Although optionally a one-piece axle may be used (not shown), preferably the pair of axle members  32  are held in opposite axial orientation by straight rigid axle connector  34 . Axle connector  34  has tightening member  35 , and a pair of receptacles  33  at the respective two ends of axle connector  34 , so that axle members  32  respectively extend outwardly from, and are demountably attached within, said axle connector receptacle bore  33 .  
         [0151]    While the axle may be optionally a one-piece axle, such as shown as reference numeral  606  in FIG. 33 herein, preferably the pair of connected oppositely extending axle members  32  form together an axle for wheels  30 .  
         [0152]    Each axle member  32  is made of solid round stock of anodized aluminum or stainless steel, approximately 0.75 inches in diameter. At the wheel-supporting end  32   a , the diameter is about 0.59 inches in diameter with shoulders  32   b  of about 0.08 inches in height, transverse to the axis of axle member  32 . These shoulders  32   b  provide a resting surface to prevent axial movement of wheel  30  upon axle member  32 .  
         [0153]    As shown in FIG. 7, each wheel  30  rotates about press fit bearings  32   b , while each wheel  30  is positioned upon each respective axle member  32  of FIG. 8. As shown in FIG. 6, at the opposite end of one axle member  32 , there is provided a hollow, threaded recess  32   c  of about 0.75 inches deep, to accommodate a connecting threaded member  32   d  of other axle member  32 , to axially connect both axle members  32  together within axle connector  34 , with a wheel  30  at each end.  
         [0154]    [0154]FIGS. 8 and 9 show how axle connector  34  is compensated along groove  38 , thereby locking axle members  32  within bushing  39 , which is within receptacle bore  33  of axle connector  34 , by tightening of tightening bolt  35   a  of tightening member  35 . Preferably bushing  39  is a PVC (polyvinyl chloride) bushing. Groove  38  is preferably {fraction (1/16)} to ⅛ inch, in width, which allows for the compression of axle connector  34  around axle members  32 . Tightening bolt  35   a  is inserted within a conventional receptacle which is a through hole at the proximal end and which is tapped with threaded grooves at the distal end, to allow for compression of axle connector  34 .  
         [0155]    [0155]FIGS. 4 and 6 also show at least one kickstand  40 , preferably a pair, respectively extending horizontally rearward from each lower portion of vertical struts  20 . Each kickstand member  40  extends rearwardly from the at least one kickstand receptacle aperture  22  of respective vertical struts  20  and each kickstand  40  is demountably attached within each respective kickstand receptacle aperture  22 . Each kickstand member  40  is preferably contoured so as to contact the ground to stabilize portable cart  1  is a parked position of rest.  
         [0156]    As shown in FIG. 5, to hold a canoe, game or cargo in place upon cart  1 , one or more adjustable load-securing straps  50  are slidably attached to both respective horizontal load supports  10  in a transverse relationship to load supports  10 . Straps  50  are preferably reinforced flexible canvas straps of about 2 inches in width.  
         [0157]    To complete portable cart  1  as a canoe or boat cart, FIG. 4 shows support cushions  13  mounted upon respective horizontal load supports  10 . Support cushions  13  are flexible, such as of rubber or foam, to support the weight of boat  2  thereon.  
         [0158]    [0158]FIGS. 10 and 11 show the precision balancing of boat  2  upon cart  1 , wherein the placement of boat  2  upon cart  1  causes cart  1  to rotate from a position of rest in FIG. 10 to a horizontal load position of FIG. 11, in the direction of the arrow.  
         [0159]    FIGS.  12 - 17  show another embodiment that converts portable cart  1  into a game cart. Alternatively, FIGS.  18 - 20  show how to convert cart  1  into a cargo wagon with a hollow well. First, in either situation, carry frame  55  is secured to horizontal load supports  10 . Although a one piece, generally rectangular frame (not shown) may be used, preferably frame  55  includes a pair of U-shaped brackets  60 ,  70  joinable together to form frame  55 .  
         [0160]    Various fasteners may be provided to horizontal load supports  10  to carry objects, such as carriers, thereon.  
         [0161]    Alternatively, for example, a clamp maybe provided to horizontal load supports  10  to carry a frame of a discrete transportable carrier directly thereon, as disclosed hereinafter with respect to FIGS.  21 - 24 . In that case, instead of the frame being integrally part of the portable chart, as in FIGS.  12 - 17 , in FIGS.  21 - 24 , the frame is clamped to the horizontal load supports  10  of portable cart  1 . Other fasteners may include longitudinally extending channel slots, such as in FIGS.  33 - 39  described further below.  
         [0162]    Meanwhile, further with respect to FIGS.  12 - 17 , U-shaped front bracket  60  extends horizontally forward from front-end receptacle apertures  12  of horizontal load supports  10 , wherein front bracket  60  is demountably attached within front-end receptacle apertures  12  at one end of horizontal load supports  10 .  
         [0163]    U-shaped rear bracket  70  extends horizontally rearward from oppositely positioned rear end receptacle apertures  12  of horizontal load supports  10  and rear bracket  70  is demountably attached within each oppositely positioned rear end receptacle aperture  12  of horizontal load supports  10 .  
         [0164]    [0164]FIG. 13 shows how frame  55  is secured to cart  1 . Each distal end of U-shaped front bracket  60  is inserted through apertures in respective ends  10   b  of horizontal supports  10  until each distal end engages a corresponding hole in each vertical support  20 , where they are held in place by pins  29 . Pins  29  engage lateral holes  18  in horizontal supports  10  and corresponding through holes  19  in distal ends of U shaped brackets  60 . Likewise, each distal end of U-shaped rear bracket  70  is inserted through apertures in respective ends  10   a  of horizontal supports  10  until each distal end engages a corresponding hole in each vertical support  20 , where it is also held in place by a pin  29 . Pins  29  engage lateral holes  18  in horizontal supports  10  and corresponding through holes  19  in distal ends of U shaped brackets  60 ,  70  of frame  55 .  
         [0165]    U-shaped brackets  60 ,  70  are preferably of hollow, anodized aluminum tubing of about 0.75 inches in diameter. The length of each distally extending side member thereof is about 23.50 inches and the width of the cross bar connecting the distal side members is about 21.63 inches. About 0.75 inches from each distal end is a scoring, to accommodate a clamp thereon, to form frame  55 .  
         [0166]    As shown in FIGS. 12 and 15 for pulling or pushing game or cargo upon portable cart  1 , handle  80  extends rearwardly at an upward angle from joints  71  of either U-shaped rear bracket  70  for pushing portable cart  1 , or from front U-shaped bracket  60  for pulling portable cart  1  (not shown). Furthermore, handle  80  may be permanently attached to either U-shaped bracket  60  or  70 , or handle  80  may be removable and demountably attached to either front U-shaped bracket  60  or rear U-shaped bracket  70 .  
         [0167]    Handle  80  has preferably two aluminum tubing connecting members about 22.5 inches in length, connected by a hand accommodating transverse bar of solid aluminum, and is 17.5 inches in width. Handle  80  includes connectors  81 , having distal sleeves, such as PVC (polyvinyl chloride) sleeves  82 , permanently affixed thereto, which are insertable within joints  71  by locking member  72 , having threaded member  72   a  which passes through bore  71   a  of joint  71  and bore  81   a  of handle  80 . Compression groove  73  exists in joint  71 , providing compression of joint  71 .  
         [0168]    Handle  80  may optionally have an auxiliary extension member and clamp (not shown), so that it can be attached to the rear frame of a bicycle (not shown), to pull portable cart  1 .  
         [0169]    To carry game  3 , as shown in FIG. 17, or to carry an injured person in a rescue operation, FIG. 12 shows portable cart  1  having fabric stretcher  100  stretched tautly between horizontal load members  10  and preferably mounted over and around front and rear U-shaped brackets  60  and  70  of frame  55 , by threading brackets  60 ,  70  through fasteners such as sewn-in loops  102  of fabric stretcher  100 , which may alternatively be made of plastic or other taut load bearing material. Other types of fasteners can be used. For example, FIG. 14 shows that loop  102   a  is openable, and closed by fastener, such as zipper fastener  102   b.    
         [0170]    As also shown in FIG. 12, handle  80  may include a pair of posts extending obliquely off of a horizontal axis of portable cart  1 , wherein a head rest cushion  85  extends between the posts to support the head and neck of an injured person being transported upon stretcher  100 .  
         [0171]    FIGS.  18 - 20  show that to carry cargo, hollow fabric cargo well  110  is attached in the same manner to frame  55 . Hollow cargo well  110  may also alternatively be made of plastic or other taut load bearing material, and covered by cover  112 . FIGS. 18 and 19 also show wider wheels  130  for use on sand or granular terrain.  
         [0172]    Assembly and Disassembly  
         [0173]    The various embodiments of the multiple-purpose portable cart can be quickly and easily assembled and disassembled. For example, for making a canoe cart from the disassembled portable cart  1 , wheel-retaining members, such as cotter pins  36 , are taken out of axle members  32  in their stored position, and wheels  30  come out. Axle members  32  are then removed from between vertical struts  20 . The axle members  32  are then clamped in a horizontal use position into receptacles  33  of rigid axle connector  34 . Axle members are inserted between vertical struts  20  and locked in place. Wheels  30  are placed upon axle members  32  and secured by cotter pins  36 . Kickstand  40  is loosened from its rest position and placed in place in receptacles within vertical struts  20 . Canoe supporting cushions  13  are installed upon horizontal load supports  10  to support a canoe or boat thereupon. Straps  50  hold the canoe or boat installed upon cushions  13  in a secure transportable position.  
         [0174]    To convert portable cart  1  into a game cart as in FIG. 17 or a rescue cart as in FIG. 12, kickstands  40  are removed and fabric stretcher  100  is installed on U-shaped frame members  60 ,  70  of frame  55  frames by fasteners such as sewn loops  102  thereof. U-shaped frame members  60 ,  70  are placed on horizontal load supports  10 , and kickstand members  40  are installed as braces for fabric stretcher  100 . Straps  50  are then installed to securely hold game or an injured party upon stretcher  100 . Then handle  80  is installed upon U-shaped bracket  60  or  70  of frame  55  to pull or push portable cart  1 .  
         [0175]    To convert portable cart  1  into a wagon to haul cargo, as in FIGS. 18 and 19, fabric stretcher  100  is removed and hollow well  110  is installed over U-shaped members  60 ,  70  of frame  55 .  
         [0176]    To make the portable chart  1  portable again, the components are disassembled in reverse into bag  120 . Strap or straps  50  are used as a carry handle or for backpack shoulder loops.  
         [0177]    While the rescue stretcher shown in FIG. 12 has its own customized stretcher  100 , in another embodiment shown in FIGS.  21 - 24 , to convert portable cart  1  to a retrofit disabled person-bearing transportable carrier cart for search and rescue operations, using conventional railed stretcher  230 , support cushions  13  are removable from horizontal load supports  10  and replaced by clamping assembly  200 . Clamping assembly  200  includes lower jaw  202 , and upper jaw  204 . While different jaw configurations can be used, the embodiment shown in FIGS.  21 - 24  shows each having longitudinally extending recesses  206  and  208  therein to grip perimeter frame rails of a load supporting transportable carrier, such as conventional railed stretcher  230  therebetween, as shown in FIG. 23.  
         [0178]    Lower jaw  202  of clamping assembly  200  includes an engaging surface  210  with threaded studs  212  which are inserted into through-holes  214  of load supports  10 , and permanently locked with nuts  216 . Upper jaw  204  is provided with a pair of oblong through-slots,  218 , to allow upper jaw  204  to slide on upper surface of lower jaw  202 , when threaded T-handles  220  are loosened. As shown by the arrows in FIG. 22 this sliding action allows for quick removal of any stretcher frame rail secured between jaw assembly  200 .  
         [0179]    [0179]FIGS. 23 and 24 are perspective views of a typical stretcher  230 , and a Stokes-type rescue basket  240 , securely clamped to portable cart  1  utilizing the previously described clamping assembly  200 .  
         [0180]    As shown in FIG. 25 in this embodiment, instead of being permanently attached to each horizontal load support  10 , removable support cushion  13  is permanently attached to removable plate  302  with an adhesive  304 . This cushion assembly is removably attachable by nuts  316  and threaded studs  312 , to each horizontal load support  10 .  
         [0181]    [0181]FIG. 26 illustrates portable cart  1 , outfitted with a plurality of racking assemblies  400 , each comprising a rail clamp  410 , an upstanding post  424 , and a hanger clamp  430 . Rack assembly  400 , when used in conjunction with additional rack assemblies  400 , allows for transportation and quick removal of essential hunting gear such as a chair stand  440 , archery equipment  441 , and rifle  442 . Other related items such as knapsacks and bedrolls may be supported by rack assembly  400 , as well. Rack assembly  400  is easily disassembled from cart  1  upon reaching a chosen destination, and the components are conveniently transported within cart l&#39;s storage backpack, such as carry bag  120  shown in FIG. 1.  
         [0182]    Also illustrated in FIG. 26 are stabilizing assemblies  450  and  460 . Assembly  450  makes use of post  420 , which is friction-fit into an inverted rail clamp  410 . Assembly  460  comprises an inverted tubular sleeve  462 , optionally permanently welded to the handle assembly crosspiece. Sleeve  462  accepts kickstand post  424  in a similar fashion to rail clamp  410 . These assemblies  450   460  serve to brace the cart  1  when it is parked.  
         [0183]    Moreover, kickstand post  424  may be used with any embodiment having a handle, such as handle  80  of FIGS. 12 and 17- 19 , or handle  81  of FIGS. 32 and 33.  
         [0184]    Turning to FIG. 27, which is highlighted in FIG. 26, an exploded perspective close-up detail view of rail clamp  410  is presented. Clamping block  411  is provided with a bore  412  to receive post  424 , an attachment face  413  including a semi bore  414 , and notch  415 , and threaded bore  416 . Plate  417  includes semi bore  418 , through hole  419 , and protruding rib  420 .  
         [0185]    As shown in FIG. 28, when threaded knob  422  is inserted into hole  419  of plate  417  and tightened into threaded bore  416  of block  411 , clamping is achieved against frame member  60 . Rib  420  is secured within notch  415  by a camming action in the direction of arrow “A”.  
         [0186]    [0186]FIG. 29 shows cantilevered hanger clamp  430 , poised to slide down upstanding post  424 . Hanger clamp  430  is provided with a bore  431 , which is notched in a similar manner to clamping receptacles  71  of the handle assembly. The notch separates the body of hanger clamp  430  into two walls. Threaded knob  422  will compress the walls surrounding the notch, thereby tightening bore  431  around post  424 . L-shaped region  432  is integrally formed with the body of the hanger clamp, and provides a strong and durable support for transporting hunting or other gear.  
         [0187]    [0187]FIG. 30 is a perspective view of an anti-tipping linkage  500 , which couples cart  1  to a bicycle. Linkage  500  counteracts cart rollover caused by centrifugal force as the bicycle negotiates turns.  
         [0188]    [0188]FIG. 31 illustrates the components of linkage  500 . Bicycle seat-stem compression clamp  510  is formed of a body portion  511 , and plate  512 , fastened by screws  513 . Bore  514  is angled so that clamp  510  remains perpendicular when installed on a typical bicycle seat-stem. Clamp  510  is provided with a bore  515  on rear face  516 , which accepts a shaft  520 . Pin  517  passes through clamp and fixes shaft  520  via a through-bore. Shaft  520  includes through-bore  522  at its distal end. Another through-bore  523  is provided slightly proximal of aperture  522 . When shaft  520  is inserted into coil spring  530 , hooked leg  531  of the spring will fit into bore  522 . A sliding collar  524  will then extend over leg  531  to prevent pull-out, and a pin  526  will be fitted into collar hole  525 , and into bore  523  of the shaft  520 , thereby securing the collar to the shaft and preventing removal of the coil spring.  
         [0189]    A shaft  540  is provided for the opposite end of coil spring  530 . Hooked leg  532  fits into bore  542  of the shaft, and collar  544  slides over and is fixed by pin  546 , fitted into collar hole  535  and shaft bore  543 .  
         [0190]    Support rails  550  and  551  are fixed to handle clamps  71  of cart  1 . The rails are bent into an inverted V configuration, and permanently affixed to block  552 . Block  552  is provided with bore  553 , into which the free end of shaft  540  is fitted. Pin  555  is inserted into through bore  554  of block  552 , and passes through bore  547  of shaft  540 , creating the continuous, secure anti-tipping linkage  500  between cart  1  and a bicycle. It is understood that during maneuvers of the bicycle, there will be no problems associated with a typical universal or pivot joint; the coil spring will absorb and disperse any rotational stresses, and will react as a 360° “living hinge”.  
         [0191]    FIGS.  32 A- 32 G,  33  and  33 A show an alternate embodiment  600  of the portable cart using four wheels  30  in an overlapped configuration. A hard molded cover  601  is illustrated although any cover or no cover can be used as well. Cover  601  covers bin  602  with lower overlapping edge cap  601   a  fitting over peripheral shoulder  602   a  of bin  602 . Bin  602  also has longitudinally extending concave channels  603 , which rest upon rails  604  of cart  600  of FIG. 32. Downward pressure of the weight of bin  602  and its contents helps stabilize bin  602  upon rails  604 , which may be optionally covered with rubber or other resilient linearly extending cushions.  
         [0192]    Although FIG. 32 illustrates portable cart  600  with covered bin  602 , portable cart  600  can be used with other embodiments, such as, for example, boat cushions  13  shown in FIG. 4, framed rail stretchers  100  as in FIG. 12, the game cart of FIG. 17, the cargo cart of FIG. 18, the conventional rescue carriers of FIGS. 23 and 24 or the gear rack of FIG. 26, among others.  
         [0193]    [0193]FIG. 33 shows a perspective view of the frame of cart  600 . Long axle  606  attaches front wheels  30  while short axle  605  attaches rear wheels  30  through respective vertical support pairs  20 . The use of four wheels doubles the carrying capacity of the cart of this invention while the overlapped positioning of the wheels maintains a short wheelbase for compactness and for maneuverability such as turning with fixed axles and the ability to easily climb ledges. For durability, the rails  604  may be a double pair of parallel rails.  
         [0194]    Double axled cart  600  has increased maneuverability, since user pushing upon an optional handle  81  enables user to lift the farther away, distal pair of wheels  30  off the ground, and the user pulling upward of handle  81  raises the nearer proximal wheels  30  off the ground.  
         [0195]    [0195]FIGS. 34 through 39 are concerned with an alternate embodiment of the horizontal load support member  10 . The alternate embodiment  610  has an integral T-slot channel  611  in its top surface to facilitate easy installation and removal of a variety of attachments, such as cushions  615  shown in FIGS.  35 - 36 , clamps  620 ,  630 ,  640 , shown in FIGS.  37 - 39 , or platform  1450  shown in FIG. 57. Load member  610  can be conveniently extruded of aluminum or magnesium; it can be used either with the two-wheel cart  1  or the four-wheeled embodiment  600 .  
         [0196]    [0196]FIG. 35 shows a resilient cushion  615  installed in the T-slot  611  of support member  610 . This cushion  615  can be extruded of a variety of rubber or thermoplastic elastomers and serves the same purpose as cushion member  13  described above. A perspective view of FIG. 36 shows cushions  615  installed on a four-wheel cart  600 .  
         [0197]    As described above, clamp assembly  200  is used to convert portable cart  1  to a disabled person-bearing transportable carrier cart. Three separate alternate embodiments of clamp assembly  200  are presented; all are compatible with the use of horizontal support member  610 .  
         [0198]    [0198]FIG. 37 shows a one-piece clamp  620  with full width top section  622  and short end pieces  621 , which mate with, and slip into the T-slot  611  of horizontal support member  610 .  
         [0199]    [0199]FIG. 38 shows clamp  630  with a full width bottom member  631  which mates with and slides into T-slot  611  of horizontal support  610 .  
         [0200]    [0200]FIG. 39 shows another alternate embodiment consisting of two short identical clamp members  640  which are inserted into the T-slots  611  of member  610  at the two extreme ends.  
         [0201]    In all cases, the short clamping sections can be sized to offer spring-like gripping action on the tubular members, or fasteners, such as thumbscrews or ball plungers (not shown) can be used for retention.  
         [0202]    FIGS.  40 - 50  show alternate embodiments for converting a conventional hand carried, railed medical rescue stretcher to a lightweight wheeled version.  
         [0203]    For example, FIGS.  40 - 42  show shortened horizontal support members  710  with tightening members  711 . Rails  713  are held either by clamps, such as shown in FIGS.  37 - 39 , or alternatively through apertures in horizontal support members  710 , as shown in FIG. 14. Horizontal support members  710  are demountably attached to vertical struts  720  having extending therethrough transverse axles  732  supporting wheels  730 . Optional pivotable kickstand  740  is attached to rails  713  by clamp  800 .  
         [0204]    As also shown in FIGS.  47 - 50 , clamp  800  includes two jaws  801 ,  802  having aperture recess  803  for insertion of rails  713  therethrough. Clamp  800  is closed and tightened by fastener  804  operated by rotatable knob  805 . Internal spring pins  806 , as shown in FIG. 47, cooperate with fastener  804  and knob  805  to tighten clamp  800  about rail  713 . Internal grooves  807 ,  808  accommodate kickstand  740  in the respective positions of support and rest, as shown in FIG. 40 and FIG. 42 respectively.  
         [0205]    [0205]FIG. 43 shows an alternate embodiment for a military rescue carrier cart  900  with a profile set low to the ground, including shortened horizontal members  910  with tightening fasteners  911 . Rails  913  are also held by clamps as in FIGS.  37 - 39 , or alternately through apertures in horizontal support members  910 , as in FIG. 14. Horizontal support members  910  are demountably attached to shortened vertical struts  920  to keep stretcher rails  913  close to the ground. Optional bent handle  945  is connected by clamps  800  disclosed in FIGS.  47 - 50 , as discussed above.  
         [0206]    FIGS.  45 - 46  show how the stretcher version shown in FIGS.  40 - 42  can be converted to a stationary medical gurney  1000 . Rails  1013  are supported by horizontal support members  1010 , which hare demountably attached to vertical struts  1020 , having axles  1032  supporting wheels  1030 . To stabilize gurney  1000 , horizontally extending tie rods  1036 ,  1037  are joined by threaded clamp  1038  or other fastening means.  
         [0207]    FIGS.  51 - 53  show a further embodiment for portable cart  1101  which folds down to a disassembled storage position as in FIG. 51 and which unfolds to an assembled position of use as in FIG. 52. Cart  1101  includes a pair of horizontal load support members  1110  laid parallel to each other, which rotate axially to move perpendicularly extending vertical struts  1120  outward from a position within a storage bag  1101   a , where vertical struts  1120  face each other&#39;s distal ends, to a position of use 90 degrees perpendicular to the storage position, where vertical struts  1120  extend in the same plane but outward from horizontal load support members  1110 .  
         [0208]    In this embodiment shown in FIGS.  51 - 53 , the resilient rails  1178  are engaged to horizontal supports  1110  such that when in a position of storage the rails  1178  are biased to return to their normal position of use, when released from the storage position, thus causing vertical struts  1120  attached to horizontal supports  1110  to pivot upward and bow, thus increasing the strength of the cart.  
         [0209]    The same is true with other embodiments of the present invention. For example, placing a boat  2  upon cart  1  causes horizontal support members  10  and wheel axles  31  to bow, giving it the strength of an uncollapsible Roman arch. The same is true with respect to stretcher or cargo hauling embodiments shown in FIGS.  12 ,  17 - 19 ,  40 - 45  and  58 - 66 , for example, wherein putting weight makes the carrier portion taut and bows the frame members into a position of strength. Also the multiple floating overlapping rails as in FIG. 14, for example, bow the rails and strengthen the cart with a load supported thereon.  
         [0210]    Moreover, vertical struts  1120  can be further strengthened in place to horizontal supports  1110  by connecting braces, such as V-shaped braces  1121 .  
         [0211]    Wheels  1130  are held by axle  1131 , which in a storage position is placed within the storage bag  1101   a . To lengthen cart  1101 , rails  1178  move away from each other within holes  1112  within horizontal supports  1110 , and are stopped from further movement by spring stop buttons  1171 .  
         [0212]    FIGS.  54 - 55  show portable cart  1201  which can be converted from a cargo hauling wagon configuration with cargo well  1290  attached to frame  1255 , to a rescue stretcher with taut rescue canvas or other stretcher  1292  when stretcher  1292 , which sits loosely above hollow well  1290  during the cargo hauling configuration, but which becomes taut when peripheral fasteners, such as zippers  1296 , snaps or the like tighten stretcher  1292  in place about frame  1255 .  
         [0213]    Optional kickstand  1240  or handle  1280  may be attached to cart  1201  by joints  1271 . A further accessory arm bag  1201   b  may be draped down from handle  1280  for further storage. An optional hard floor member  1294  may be provided below stretcher layer  1292  within cargo well  1290  for cargo hauling strength.  
         [0214]    [0214]FIG. 56 shows optional ski attachments  1330  for cart  1301 , wherein ski portions  1331  are attached by braces  1332  to vertical struts  1320 . The length of braces  1332  is equal to the radius of wheels  30  in previous embodiments.  
         [0215]    [0215]FIG. 57 shows optional platform base  1450  for supporting object such as camera tripods, cooking devices, ordnance, etc. upon cart  1401 . Platform base  1450  slides within channels  1411  and is secured in place by fasteners such as recessed hex nuts.  
         [0216]    [0216]FIG. 58 shows a portable cart frame of this invention configured as a cargo hauler or as a multi-victim stretcher. The cart includes two outer longitudinal horizontal parallel rigid load support frame members  1501  which are preferably tubular. The cart also may include an optional center frame member  1502 , also preferably tubular, as well as optional transverse frame members  1503 , overhead tube frame  1505 , two vehicle actuators, such as wheels  30  and axle  32 . It is contemplated that in snow conditions the vehicle actuators can alternatively be skis, such as shown in FIG. 56 herein.  
         [0217]    Also as shown in FIG. 58, fasteners, such as cotter pins  1504  are used to attach horizontal support members  1501  and  1502  within holes, such as circular holes for tubular shaped horizontal support members in transverse members  1503 .  
         [0218]    Also as in FIG. 58, vertical struts having the wheel subassembly with wheel  30  are attached to outer horizontal support members  1501 , such as tubes, with mechanisms  1506  which permit quick attachment and detachment. Attachment clamps  1507  secure overhead handle  1505  to outer ends of horizontal support members  1501 .  
         [0219]    Although not shown in the drawings, any of the embodiments herein shown in all the drawing FIGS.  1 - 70  may have vertical length adjustment means (not shown), such as a sleeve containing a telescoping shaft, the sleeve having a spring means for urging said shaft in a selectably extendable manner out of the sleeve and a lock for locking the telescoping shaft into a selected extended position.  
         [0220]    [0220]FIG. 59 shows a single cargo or person hauling fabric top surface sheet  1512  which can be made of canvas or similar material. Sheet  1512  preferably has sewn longitudinal pockets at the outer edges to accept horizontal support members  1501  and a central pocket  1513  to accommodate optional central frame member  1502  when inserted in direction  1514  as shown. Optional apron sections  1513  can be flipped over the side edges.  
         [0221]    [0221]FIG. 60 shows the frame of this cargo hauling or multi-victim cart readjusted to foreshorten the distance between transverse members  1503  by securing cotter pins  1504  in holes in horizontal support members  1501  and  1502  which are located farther in from the ends.  
         [0222]    As shown in FIG. 61, this adjustment can be used to accommodate separate stretchers  1525  with locating extensions  1526  and handles  1527 .  
         [0223]    [0223]FIGS. 62 and 63 show end views of the quick disconnect/connect mechanisms  1506  (in viewing direction “6262” in FIG. 58) with horizontal support member  1501  shown optional as tubular in cross section. Top clamping member  1532  has slot  1531  which permits it to slide from the locking position shown in FIG. 62 to the unlocked position of FIG. 63 thereby releasing side horizontal support member  1501  from the wheel  32  subassembly which continues below lower clamp jaw  1533 .  
         [0224]    In FIG. 62, spring  1534  is compressed since the locking shaft concentric with it has been threaded downward by turning handle  1530  in a clockwise direction.  
         [0225]    In FIG. 63, handle  1530  has been turned about 180 degrees counter-clockwise thereby permitting spring  1534  to push up on top member  1532  releasing horizontal support member  1501 .  
         [0226]    [0226]FIG. 64 is a partial end cross section (in plane “6464” of FIG. 58) of clamp  1507 . The split  1544  in clamp body  1540  permits selective grasping of horizontal support member  1501  as per the clamping force from screw  1542  as applied through knob  1541 . Stainless steel insert  1543  prevents collapse of the end of tube  1505  of the overhead assembly.  
         [0227]    [0227]FIG. 65 shows yet another embodiment of the cart of this invention as a frame for a portable operating room table or a gurney. This portable operating room table/gurney includes side horizontal support members  1550 , such as, for example, frame tubes, auxiliary side bars  1551 , transverse frame members  1552 , vertical struts  1553 , overhead support frames  1554 , overhead rails  1555 , trolley  1556 , and attachment clamps  1557 . The portable operating room table/gurney rides on four wheels  30  with axles  32 .  
         [0228]    The fully configured gurney is shown in FIG. 66. Additional features shown include flexible fluid capture collection sling  1562 , fluid collection tube  1563 , fluid collection tank  1564 , adjustable side clamp  1560 , side rest or surgical instrument table  1561 , wheel brakes  1558 , and overhead accessory  1569  for attaching lights or other surgical accessories.  
         [0229]    [0229]FIGS. 67 and 68 show the construction and operation of wheel brake assembly  1558 . Brake frame  1570  is rigidly attached to vertical strut  1553 . Upper pivot frame  1572  works in conjunction with handle/link  1574 , curved spring link  1573 , and plunger shaft  1575  to form an “over-center” mechanism with two stable states, clamped or unclamped.  
         [0230]    In FIG. 67, handle  1574  is pushed down into a snap-locked position pushing tip  1576  into contact with wheel  32  tire  1571  thereby contacting the top surface and deforming it to prevent wheel  32  from rotating.  
         [0231]    [0231]FIG. 68 shows the “brake-off” position which is obtained by lifting handle  1574  past the center position thereby lifting tip  1576  out of contact with tire  1571 .  
         [0232]    [0232]FIG. 69 is an end view of adjustable side clamp  1560  with side tube  1550  and auxiliary rod  1551  in cross section (see plane “ 69 - 69 ” in FIG. 66). Instrument table  1561  attached to clamp body  1580  can be moved longitudinally along tube  1561  and locked in place as desired by turning knob  1581  which impinges the end of screw  1582  against horizontal support member  1550 .  
         [0233]    [0233]FIG. 70 shows an exploded view of attachment clamp  1557  used in a variety of locations on overhead frames  1554 . It includes main body  1590  with groove  1591 , outer clamp member  1593  with lip  1593  and screw  1596  with knob  1595 . In operation, lip  1593  pivots within groove  1591 ; tube  1554  is grasped by the concave surfaces of body  1590  and outer member  1593  as tightened by screw  1596 . A tube end  1594  which can represent a tube  1555  or an accessory  1568  is inserted in the hole in the end of body  1590  and locked.  
         [0234]    It is further noted that other modifications may be made to the present invention, without departing from the scope of the invention.