Abstract:
An easily pulled, rolling cooler for storing refrigerables which can be manually towed by pulling a handle that is designed to resist torsion. The cooler has two wheels that are located directly under the cooler center of gravity to minimize pulling strain for the user. Provision is made for the handle to be folded down and stored on the cooler lid when not being used for towing. The cooler bottom is V-shaped, providing good ground clearance for the back end of the cooler when being towed over uneven ground. The cooler is light weight, compact and easily fitted in a car trunk or in a van for travel to picnics.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to coolers for temporary storage of refrigerables, and in particular to a rolling cooler having attached wheels and a handle for pulling. 
     2. Background 
     Portable coolers, such as those typically used for storing cold cans of beer and soda for picnics, are usually light in weight unloaded and are designed to be carried. When fully loaded with cans and bottles, these coolers can prove to be heavy and awkward to carry any significant distance. 
     Some types of rolling coolers for temporary storage of refrigerables have been available for decades. These are mostly used by summertime street vendors, and range all the way from those set up on a tricycle wheel driven arrangement, to those which include two or four wheels and are manually pulled using an attached handle. 
     These known rolling coolers are usually designed for heavy usage and, as a result, are relatively heavy in weight and expensive to manufacture. They are also unsuitable in configuration for easy storage in the back of a car or light truck. There is thus a need for an inexpensive rolling cooler that can be easily pulled without undue strain on the hand and arm, over flat or uneven surfaces, and can be carried in the back of a car or light truck. 
     SUMMARY OF THE INVENTION 
     The invention is a rolling cooler for storing refrigerables that can be manually towed, using an attached pivoted pulling handle that is designed to resist torsion. 
     Two cooler wheels are located directly under the cooler center of gravity to minimize pulling strain for the user. Provision is made for the pulling handle to be stored on the lid of the cooler when not being used for towing. The cooler has thick walls for insulation, with the bottom wall being V-shaped to provide adequate ground clearance for the back end of the cooler when being towed on its two rubber tired wheels. 
     Accordingly, it is a prime object of the present invention to provide a rolling cooler that can be pulled easily without undue strain on the hand and arm of a user over flat or uneven ground. 
     An advantage of the present invention is low weight as compared with other available rolling coolers. Another advantage is the cooler compact storage form. when not in use. This facilitates storage of the cooler for travel or picnics, in the back a car or truck. 
     A further advantage is the relatively low cost of the cooler. 
    
    
     Further objects and advantages of the invention will be apparent from studying the following portion of the specification, the claims and the attached drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a pullable rolling cooler according to the present invention, particularly showing the pulling handle folded forward and stored in a groove in the top of the cooler lid; 
     FIG. 2 is a side elevation view of the invention cooler being pulled, particularly showing the handle fixed rigidly to the cooler case for pulling, and the cooler V-shaped bottom surface having good ground clearance; 
     FIG. 3 is a perspective view of the invention cooler lid, particularly showing the cut-out grooved portion for storing the handle; 
     FIG. 4 is a perspective view of the invention cooler case, particularly showing a pivotal mounting plate for the handle and a latch plate fastened to the front end of the cooler case; 
     FIG. 5 is a partial perspective view of the bottom of the invention cooler; particularly showing two rubber-tired wheels mounted on an axle attached to the cooler case bottom surface; 
     FIG. 6 is a partial perspective view of the front end of the cooler, particularly showing details of the pulling handle and the attached strut assembly that is used to hold the handle rigid; 
     FIG. 7 a perspective elevation view of the cooler handle, particularly showing detail of its anti-torsion construction. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring particularly to FIG. 1, there is shown a perspective view of a pullable, rolling cooler  1  according to the present invention, which is shown in a stationary mode, with its pulling handle stored in the cooler lid  2  on top of the cooler case  4 . The handle  6  has one end attached pivotally to a mounting plate  12  at the front end of the case  4 , and is stored, removably fastened to a groove  8  which is cut in the lid  2 . A slotted latching plate  14  is attached to the front end of the case  4  and serves to secure the handle  6  rigidly in position when extended. Two rubber tired wheels  10  on an axle fixed to the bottom portion of the case  4 , support the stationary cooler  1 . 
     In this condition, the lid  2  can be lifted off the top of the case  4 , with the attached handle  6  pivoting on its mounting plate  12 , for full access to the case contents. 
     In FIG. 2, the cooler  1  is shown being pulled by its handle  6 , which is braced rigidly by a strut assembly  18  that pivots on the handle  6  at one end and locks in to the latching plate  14  on its distal end. It should be noted that the bottom portion  16  of the case  4  is V-shaped, and the wheels  10  are located at the center of the V which corresponds approximately to the cooler center of gravity. There is therefore good ground clearance for the back end of a cooler when being pulled, while the wheels  10  carry most of the cooler weight. Because of this design, relatively little weight and strain is transmitted through the handle  6  for pulling by a user. 
     The lid  2  is secured to the case  4  by a stepped portion  3  on the lid underside, which projects into the top of the case cavity and fits closely to the inside surface of the case walls. 
     Refer now to FIGS. 3 and 4 which are respectively, perspective views of the lid  2 and the case  4 . Both the lid  2  and the case  4  are fabricated using rigid, molded foamed plastic with a smooth outer surface. This material provides good thermal insulation properties to protect the contents of a cooler, in addition to being light in weight and sturdy. As an alternative, a light weight composite material could be used for the,case  4  and lid  2 . 
     A deep groove  8  is cut and shaped in the top surface of the lid  2  to store the handle  6  with its strut assembly  18  folded flat against the sides of the handle. The handle  6  is held in the groove  8  by a fastener patch  20  of hook-loop synthetic material that is adhered to the floor of the groove  8 . A mating fastener patch of hook-loop synthetic material is also attached to the handle  6 , and located so that the fastener patch on the handle will engage the fastener patch on the floor of the groove  8  in the lid  2  when the handle  6  is rotated and nested in the groove. The fastener patches can be easily disengaged from each other when desired, and the handle  6  may be removed from the groove for pulling the cooler. 
     The case  4  has thick walls surrounding a large rectangular cavity  5  for storage of ice and refrigerable materials. A mounting plate  12  having two parallel projecting ears which include a hole for a fastening pin, is attached to the front end of the case, adjacent to the case top edge. The mounting plate  12  provides a means of pivotably attaching an end of the handle  6  to the case  4 . A slotted latch plate  14  for bracing an extended handle, and a wheel-axle assembly for supporting the case, complete the list of components that are at attached to the case. The latch plate  14  is made of two opposing curved members made of metal or plastic that each include at least one slot near the lower end of the member. These members may be joined to facilitate their fastening to the case. A standard commercial slotted latch plate may be used where available. As is apparent from FIG. 4, the case assembly is relatively simple, requiring little special manufacture other than molding and forming the case itself. 
     In this connection, it is instructive to observe the partial perspective view of the case bottom surface in FIG.  5 . Here, an axle  22  holding two rubber tired wheels  10 , is fastened by standard metal fastening fixtures to the case bottom surface  16 . 
     Refer now to FIG. 6 which shows the handle  6  and its attached supporting strut assembly  18 , pivotally attached to a mounting plate  12  located on the front end of the case  4 , just below the groove  8  in the lid  2 . As depicted, with the strut assembly  18  folded flat against the sides of the handle  6 , the handle may now be pivoted forward and stored in the lid groove  8 . 
     The handle  6  is a long rigid metal bar that has a handle grip  7  fastened to one end, and has an arcuately-shaped portion  26  forming its distal end which is attached pivotally with a pin to the mounting plate  12 , and thereby to the case  4 . A fastening pad  21  made of hook-loop synthetic material is adhered to the surface of the handle facing the lid groove  8 , and is located to mate and engage with an opposing fastening pad  20  of the same material that is adhered to the lid groove  8 . This provides a means for the handle  6  to be held in a stored position on the cooler lid  2  when desired, and also to be easily disengaged from the cooler lid and erected for pulling when necessary. 
     The strut assembly  18  pivots on the handle  6  about two-thirds of the handle length down from the grip  7  end on a pivot pin  27 . The strut assembly  18  comprises two identical strut members  24  which are plates made of a springy material, and which are joined at their mid-point by a stiffening plate. The stiffening plate is designed to separate the strut members by the handle width plus a small clearance to allow the strut assembly  18  to be folded over the handle for nesting in the groove  8  in the top of the lid  2 . 
     At the free end of each strut member  24  is a portion  25  that is bent outward at an acute angle. These bent portions serve as fastening lips that are used to engage the latching plate  14  which is on the front end of the cooler case below the handle  6 . 
     Referring now to FIG. 7, the handle  6  is designed particularly to resist the torsion that may occur during pulling the cooler. The bar portion of the handle is made wide, and includes a plurality of cut-out triangular shaped cavities  30 . These cavities are specifically shaped and arranged to reduce handle weight while still maintaining high resistance to torsion. A first hole  32  is bored through the handle for pivotally mounting the strut assembly  18 , and a second hole  34  is bored through the arcuate end  26  for attaching to the handle mounting plate  12 . 
     The cooler is light in weight and easy to pull. It is strong enough to store a large quantity of the typical picnic provisions needed for a family, and provides easy access to the cooler contents. Due to its simple construction, it is also low in cost. 
     From the foregoing description, it is clear that the preferred embodiment of the cooler achieves the objects of the present invention. Various modifications may be apparent to those skilled in the art. These modifications are considered to be within the scope and spirit of the present invention and are encompassed thereby.