Abstract:
An adjustable handcart that provides a horizontal platform for transporting items of cargo or people, such as a patient immobilized upon a spine board. The handcart includes a platform and a platform extension slidably connected at one end and held in place by a lock mechanism. A wheel assembly extends downwardly from the platform to support the platform in a substantially horizontal position off the ground. On the end opposite the platform extension, handles are attached. The handles may be detachable and/or rotatable (to facilitate folding), thereby allowing the handcart to be easily cleaned, stacked, or compacted as needed.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates generally to adjustable wheeled devices for manually transporting people or cargo and more particularly to a handcart that is especially useful for transporting people or supplies during mass triage situations. 
   2. Description of the Related Art 
   Many different wheeled devices for manually transporting persons or items of cargo are known to exist. Indeed, devices such as wheelchairs, gurneys, handcarts, or dollies are used everyday to transport everything from injured people to kitchen appliances. Many of these devices utilize extendable and retractable platforms to enable compaction of the device into a small space or to adjust the carrying area of the device to accommodate different size loads. 
   More specifically, adjustable dollies exist that allow for different size or weight loads to be removably attached to the dolly while preventing excessive movement of the load during transport. For example, U.S. Pat. No. 6,386,560 discloses a dolly that includes a dropped center floor area, with pivoting casters disposed at each corner thereof beneath a raised end portion at each end of the dropped center floor. While the dropped central floor area provides the lowest possible overall height (only 1.5 inches from the ground) for overhead clearance through standard doorways, such a design requires bending over to near ground level to retrieve cargo. Moreover, this dolly cannot be used to transport supine patients. 
   In a medical context, spine board dolly apparatuses, such as that disclosed by U.S. Pat. No. 5,871,220 issued to Lombard, allow the conversion of an ordinary spine board into a wheeled transport device. Lombard&#39;s invention essentially consists of a sleeve with wheels that slips over and is attached with a belt to one end of a spine board. While this invention provides a clever way for a single person to transport a patient or cargo on a platform, the spine board is not kept in a preferred horizontal position and has a relatively high center of gravity. This can result in dumped cargo or can leave a patient uncomfortable and at risk of further injury from being tipped over or dropped. Moreover, each of Lombard&#39;s apparatuses must be assembled before use, which could cost precious time in a mass casualty situation. 
   Thus, there remains a need in the art for an adjustable handcart that is adaptable for use with both people and cargo, is easy to clean and disassemble, can be operated by a single person, stores compactly in stacks, and keeps passengers or cargo in a stable, horizontal position. 
   SUMMARY OF THE INVENTION 
   The invention relates in general to adjustable handcarts. More particularly, the invention relates to horizontal handcarts that can be used to transport items of cargo or patients immobilized upon spine boards. In one embodiment, the handcart of the invention includes a substantially horizontal platform and a platform extension slidably connected at one end and held in place by a lock mechanism. To support the horizontal platform off the ground, a wheel assembly is attached to the bottom side of the platform. On the end opposite the platform extension, handle means are attached. The handle means may be detachable and/or rotatable (to facilitate folding), thereby allowing the handcart to be easily cleaned, stacked, or compacted as needed. 
   The platform extension allows the handcart to change size in order to accommodate items of various lengths, such as a pediatric or adult size spine board. Preferably, clamp assemblies, stop tabs or plates, friction strips, and a stand are also included on the platform to ensure the secure attachment of items and to make the platform self-standing in a substantially horizontal position. 
   Thus, the present invention provides significant advancement over the known related art by enabling a single person to readily transport a patient or supplies of a wide range of sizes in a stable, substantially horizontal position. 
   Therefore, it is a primary objective of the invention to provide a handcart that is adjustable for different size loads. 
   Further, an object of the invention is to provide an adjustable handcart that stays substantially horizontal when stationary or moving. 
   Another object of the invention is to provide an adjustable handcart that can be operated by a single person. 
   Still another object of the invention is to provide an adjustable handcart that is easy to disassemble and clean. 
   Yet another object of the invention is to provide an adjustable handcart that facilitates stacking and storage. 
   An additional object of the invention is to provide an adjustable handcart that is durable, economical to produce and inexpensive to utilize. 
   Various other purposes and advantages of the invention will become clear from its description in the specification that follows. Therefore, to the accomplishment of the objectives described above, this invention includes the features hereinafter fully described in the detailed description of the preferred embodiments, and particularly pointed out in the claims. However, such description discloses only some of the various ways in which the invention may be practiced. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  depicts an exploded side perspective view of a preferred embodiment of the invention. 
       FIG. 2A  shows an assembled perspective view of the embodiment of  FIG. 1 . 
       FIG. 2B  shows the embodiment of  FIG. 2A  compacted for storage, with the platform extension all the way in and the handles rotated 180 degrees clockwise from their original position. 
       FIG. 3A  depicts in perspective view a stack of the compacted handcarts of  FIG. 2B . 
       FIG. 3B  schematically illustrates in elevational view the same stack shown in  FIG. 3A . 
       FIG. 4  shows an elevational view of an embodiment of the invention that features a removable spine board. 
       FIG. 5  depicts in side perspective view a basic alternative embodiment of the invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The invention generally relates to a handcart featuring a platform with an extension that adjusts in length between a compact and an extended state to accommodate items of various sizes. The handcart of the invention is suspended off the ground in a substantially horizontal position by a wheel assembly and, preferably, a stand. A handle or handles are attached to the platform on the end opposite to the platform extension and are preferably removable and rotatable for easy cleaning and storage. 
   The invention is especially useful in mass triage situations due to its ease of handling, stability, and adaptability in accommodating loads (e.g., spine boards) of various sizes. Moreover, the preferred embodiment of the invention allows one to compactly stack a plurality of carts at a desired location, thereby enabling a large-scale response in areas with a high density of people (e.g., airports, sports stadiums, etc.). 
   Turning to  FIG. 1 , a preferred handcart  2  of the invention in shown in an exploded, side perspective view. The handcart  2  has a platform  4  that includes a first end  6  and a second end  8  that are connected to a first side bar  10  and a second side bar  12 . Ideally, one or more crossbars  11  may be welded or otherwise affixed to the platform  4  in increase durability. A platform extension  14  having a first side piece  16 , a second side piece  18  and a connecting end  20  is manufactured such that the platform extension  14  slidably engages first end  6  of platform  4  in coaxial alignment with first and second side bars  10  and  12  (as shown by arrows  22 ). Platform extension  14  is then secured in a predetermined position with pull pin  23  and removable bolt  24 , each of which is placed through, and secured to, a nut  25 . In this case, the position of the platform extension  14  is determined by locking the pull pin  23  and removable bolt  24  into a desired hole  26 . Preferably, a stop plate  27  is also attached to end  20  (or formed as a single piece with end  20 ) to provide a means for better securing a load to the handcart  2 . 
   Although not illustrated herein, it would be understood by one skilled in the art that the platform of the invention may take other forms without departure from the invention. For example, the platform might be manufactured from a single piece of light, flat metal with brackets on one end to slidably engage the platform extension. Thus, the preferred embodiment should not be construed to limit the invention to the particular structure just described. 
   Proximate to the second end  8  of platform  4 , handles  24  are connected with an variety of known joining means, such as bolts  28 , washers  29 , and nuts  30 . Preferably, the joining means allow the handles  24  to be rotatable (for compactness during storage) in the plane defined by the platform and removable for decontamination/cleaning. In such a case, a stop tab  31  extends from the second end  8  to prevent rotation of the handles  24  past the point of horizontal alignment with side bars  10  and  12 . The handles  24  are ideally made up of a pair of handle bars  32  and  34  connected by a bar  36  for added durability. For added comfort and safety, soft hand-grips  38  and end caps  40  may be added to the handle bars  32  and  34  as shown. 
   Mounted proximally to the first end  6  of platform  4  is wheel assembly  42 , which includes an axle  44  and wheels  46 . Preferably, the axle  44  is threaded through a pair of pipe sections  48  that are welded or otherwise attached to a pair of angled support bars  50 . Although it is not shown, it should be understood that a single wheel or more than two wheels could be part of the assembly  42  in lieu of design shown. Preferably, the tires on wheels  46  are maintenance free (e.g., puncture proof tires). Also preferred is the addition of a stand  52  extending downwardly from the platform  4  such that the platform is held in a substantially horizontal position when not being held by a user. The stand  52  also helps to prevent accidents or damage to cargo caused by a user dropping the handles  24 . 
   Several accessories can be attached to the platform  4  to increase its versatility. Referring again to  FIG. 1 , a strap  54  can be added to provide a support for cargo, a stretcher, a spine board, or other item. Moreover, clamp assemblies, such as brackets  56 , and friction strips  58  provide a means for securing items to the handcart  2 . Preferably, friction strips  58  are made from hard rubber and are attached to the platform with adhesive. 
   As shown in  FIGS. 2A and 2B , the handcart of the invention can assume a range of configurations, from fully extended ( 2 A) to full compacted ( 2 B). Moreover, the compacted state facilitates the stacking of handcarts as shown in  FIGS. 3A and 3B . 
   As shown in side elevational view in  FIG. 4 , the invention is especially useful in combination with a spine board. Hence, a “mobile spine board” is created by securing a spine board  60  to the platform  62  through clamps  64 . 
   Turning to  FIG. 5 , an alternative embodiment of the invention is shown. Here, the handcart  66  includes a first end  68 , a second end  70  and two side bars  72  and  74 . A platform extension  76  is slidably attached to the first end  68  as shown in  FIG. 1 , and a simplified handle means  78  is attached proximal to the second end  70 . Wheel assembly  80  then completes the handcart. 
   As will now be clear from the description above, the handcart of the invention has many advantages over existing carts. Its low profile and center of gravity provides stable mode of transportation for supplies or patients. Moreover, in critical mass casualty situations where “manpower” can be very limited, the invention allows one person to gather and transport victims to a triage center. Furthermore, the compact and lightweight design of the invention allows one person to deploy multiple stacked handcarts or up to 350 lbs. of cargo. Preferably, the platform, platform extension, and handle means of the invention are constructed from aluminum. However, any suitably durable and lightweight material may be utilized. All of these features make the handcart of the invention ideal for rapid deployment applications in both military and civilian settings. 
   Various changes in the details and components that have been described may be made by those skilled in the art within the principles and scope of the invention herein described in the specification and defined in the appended claims. Therefore, while the present invention has been shown and described herein in what is believed to be the most practical and preferred embodiments, it is recognized that departures can be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent processes and products.