Mobile cooler with retractable wheels and handles

A mobile cooler including a compartment having pivotable wheels and a handle assembly for pulling the cooler. A pair of wheel assemblies individually pivot within recesses in the cooler from a raised to a lowered position. In the lowered position the cooler can be transported over smooth or uneven terrain. The handle telescopes partly into the compartment, and partly folds down by a pair of hinges to fit within recesses in the compartment lid. The handle length can be adjusted to suit the user.

FIELD OF THE INVENTION 
The present invention relates to portable cooler chest, and more 
specifically to a portable cooler having a set of wheels and a handle 
enabling a user to transport the cooler over the ground. 
BACKGROUND OF THE INVENTION 
Coolers are generally known in the art. The most commonly used coolers are 
make of plastic, usually having some form of insulation between the inner 
and outer walls. Larger models capable of holding several bottles of 
refreshments, picnic food and copious quantities of ice require the 
recreator to carry the cooler by a pair of handles typically mounted on 
either side of the cooler. When the unit is nearly full, it can weigh in 
excess of fifty or so pounds, making carrying over long distances 
difficult and causing strain to the user. 
In an attempt to remedy this deficiency in design, several patents address 
the problem of transport by adding wheels or a carting assembly to the 
cooler. U.S. Pat. No. 4,846,493, issued to Mason, describes a portable 
cooler with retractable wheels and a folding handle. The wheels are 
mounted on a single axle and must be raised or lowered by pivoting on a 
rod. Mason requires the cooler to be lifted by the handle to raise the 
side opposite the wheels off the ground, thereby still resulting in strain 
to the user. The locking mechanism is subject to jarring when moving over 
uneven terrain, thus potentially causing the wheel mechanism to jump out 
of the retaining hook member. The retracting arm and lock mechanism 
project outward adding additional width to the unit, making it more 
cumbersome to load into a car trunk and the design less aesthetically 
pleasing. 
U.S. Pat. No. 4,724,681, issued to Bartholomew et al., shows a portable 
cooler having foldable handle mechanism whereby the handle segments fold 
at joints to wrap around the cooler compartment. The foldable joint at the 
base of the handle where it connects with the cooler compartment may be 
insufficient to withstand the stress of a fully loaded cooler. Other 
coolers have wheel mechanisms that protrude from the sides of the cooler, 
adding to the width of the unit and lessening its aesthetic appeal. 
It would be desirable to have a cooler that was constructed to have a 
sturdy handle/carrying mechanism that would withstand heavy use, yet 
remain convenient for use by adults or children. Furthermore, such a unit 
would have a retractable wheel mechanism that conveniently and without 
undue manipulation folds the wheels up into the body of the cooler when 
not needed, thus providing a stable compartment. 
SUMMARY OF THE INVENTION 
Accordingly, the above-mentioned deficiencies are remedied by the present 
invention, which provides a portable cooler having a pair of adjustable 
wheels and a telescoping collapsible handle for transporting the cooler 
over the ground. More particularly, the present invention provides a 
cooler compartment having a lid, bottom, sides, front and back; a recess 
in each corner of the lower end of the sides sized to receive a wheel; a 
first arm extending outward from each recess each arm having an aperture 
located at the distal end capable of receiving a pin; a pair of 
essentially parallel apertures disposed vertically in the back; a pair of 
wheel assemblies one disposed within each recess each assembly comprising 
a wheel, an axle disposed axially through the center of the wheel, a 
bracket connected to each end of the axle so as to permit free rotation 
about the wheel axis, a second arm extending from the bracket having an 
aperture at the distal end, a first hinge means comprising a first pin 
capable of pivotably connecting the first arm to the second arm by passing 
through the apertures; and a handle assembly for maneuvering the cooler 
over terrain comprising a pair of support members, each support member 
comprising a handle, an upper section comprising a first tube 
telescopingly engaged with a second tube, the handle being attached to the 
first tube, a lower section comprising a third tube sized to fit slidingly 
within the vertically disposed back aperture, and a second hinge means for 
pivotably connecting the second tube with the third tube. 
The wheel assembly permits the wheel to be raised and out of the way when 
the cooler is not in a transport mode, thus providing a stable cooler. 
Accordingly, it is a principal object of the present invention to provide a 
mobile cooler capable of being conveniently transported on the ground. 
It is another object of the present invention to provide a mobile cooler 
having a set of retractable wheels and a collapsible handle. 
It is still another object of the present invention to provide a mobile 
cooler having a set of retractable wheels which can be drawn over soft 
ground, such sand. 
It is yet another object of the present invention to provide a mobile 
cooler having a telescoping handle which can collapse to fit conveniently 
and securely within the general exterior structure of the cooler 
compartment.

DESCRIPTION OF THE INVENTION 
Referring to the drawings in which like numerals describe like parts 
throughout the several figures, FIGS. 1 and 2 are perspective drawings of 
a portable cooler shown generally as an apparatus 10, shown in an extended 
position suitable for being pulled or pushed by a user. A generally 
rectangular cooler 12 comprises a lid 14, left and right sides 16 and 18, 
a bottom 20, a front 22, and a back 24. The cooler 12 can be made of any 
commonly used material, such as plastic, and is preferably of a double 
walled construction with an internal sandwiched layer of insulation, such 
as Styrofoam. The lid 14 is connected to the back 24 by a conventional 
hinge (not shown). Alternatively, the lid 14 is not hinged, but fits 
snugly by a mating set of grooves (not shown) in the inside of the lid 14 
and the cooler 12. The cooler can be held in a closed position by optional 
latch 26, which can be attached to the lid and detachably engages a 
protrusion on the cooler 12, as is commonly known in the art. 
A pair of side handles 28 are attached at the upper portion of sides 16 and 
18 to enable a user to hand carry the cooler 10. 
A pair of wheel assemblies 30 located on the left and right sides 16 and 18 
each comprise a wheel 32, which is made of rubber, plastic, metal, or the 
like, and is relative to its diameter to provide increased surface area, 
making transport easier over variable surfaces, such as sand and gravel. 
The width and diameter of the wheel are not critical, but the wheels are 
intended to be wide enough to easily roll over sand or other soft 
surfaces. In a preferred embodiment, the wheel is approximately four 
inches long and the diameter is three inches. The wheel 32 has an axle 33 
passing axially through the center. The axle 33 is connected at each end 
to a rigid C-shaped bracket 34, which permits free rotation of the wheel 
32 on its axle 33. Extending perpendicularly from the outside of the 
C-shaped bracket 34 is a pivotable arm 36, which connects to a pivot hinge 
37 having a horizontal axis of rotation. The hinge 37 allows vertical 
arcuate movement of the bracket 34 from a position above the hinge 37 to a 
position below the hinge 37. Movement of the arm 36 beyond the vertical 
downward position is restricted by a right triangle shaped stop block 38. 
At the corner of the right angle is pivotably connected the hinge 37, 
connecting the wheel assembly 30 with the cooler 12. The block 38 is 
mounted to the cooler 12 so that the arm 36 abuts one side of the right 
triangle when in the down position, as shown in FIGS. 2 and 5. 
A pair of recesses 40 (one for each wheel assembly) in the rearward portion 
of the cooler 12 permit placement of each wheel assembly 30 when in a 
retracted position, and a recess 42 permits pivoting of the wheel assembly 
30 to the down position to gain contact with the ground when the wheel is 
in the down position. FIG. 3 is a side elevational view which shows the 
wheel assembly 30 in an up position, fitting within the recess 40. 
A pair of handle assemblies 50 allows a user to roll the cooler 12 on the 
wheel 32 when the wheels 32 are in the down position and the cooler 12 is 
tilted back. Each handle assembly 50 comprises a handle grip 52, made of 
molded rubber or plastic, which form fits over the short portion of a 
hollow L-shaped tube 54. The long section of the L-shaped tube 54 fits 
telescopingly within a hollow tube 56. The tubes 54 and 56 are 
disengagingly held in a fixed relative position by a spring loaded pin 58 
(not shown) in which the pin 58 attached to the tube 54 fits into a hole 
60 in the tube 56, in a conventional manner. When a user wishes to shorten 
the overall length of the handle, he or she need merely depress the pin 58 
transversely into the tube until it clears the thickness of the tube 56, 
and then slide the tube 54 into or out of the tube 56. Several spaced 
holes 60 are possible so as to provide an adjustable length feature to the 
handle assembly 50. This provides an additional advantage in that shorter 
or taller people can have the same ease of use. Optionally, a series of 
holes can be positioned around the circumference of the tube 56 so that 
the handle 52 can be turned inward or outward at the user's choice, and 
locked in place. 
The tube 56 is connected to a vertically pivotable joint 62. The pivot 62 
is connected in turn to a lower telescoping tube 64. The pivot 62 permits 
movement of the tube 56 from an approximately 90.degree. angle to an 
approximately 180.degree. angle with respect to the lower tube 64, but not 
beyond. In this manner the handle assembly will support the torque when 
used as a lever. The lower tube 64 fits telescopingly within a base tube 
66, shown in phantom in FIG. 4. The base tube 66 is disposed within a 
support base 68 integrated with the back 24. The tubes 54, 56, 64 and 66 
can be hollow lengths of plastic, aluminum, steel, or other strong rigid 
material, cut and formed as necessary. The tube 
A locking pin 69 is built into the support base 68 and extends transversely 
through the base and through an aperture (not shown) in the lower tube 64 
when the tube 64 is in the extended position from the base. The pin 69 
fixedly maintains the tube 64 in the extended position until the user 
withdraws the pin 69 fully or at least partly to be removed from the 
aperture in the lower tube 64. 
The handle assembly 50 is shown fully extended in FIGS., 1 and 5. FIG. 5 
shows the apparatus 10 tilted back on wheels 32 (shown in the down 
position) and ready for transport by a user. FIG. 5 shows an alternative 
embodiment of the positioning of the L-tube 54 and pin/hole 58/60. In this 
embodiment the handle grips 52 have been rotated inward 90.degree., 
providing an alternative arrangement for maneuvering the apparatus 10. 
FIG. 2 shows the handle assembly 50 in a folded position, whereby the tube 
54 is telescoped within the tube 56 and the tube 64 is telescoped within 
the base tube 66. The joint 62 pivots so that the tubes 54 and 56 lie flat 
on the lid 14 in a set of the recessed grooves 70. This provides a flat 
surface on the lid 14 so that boxes or other apparatus 10 can be stacked 
on top. Moreover, the lid can be opened and the handle assembly 50 will 
pivot as well, so that the user does not have to manipulate the handle 
assembly 50 separately merely to gain access to the contents of the cooler 
12. 
In use the apparatus 10 can contain any variety of items, such as food, 
drink, ice and the like in the cooler 12 compartment. The handle grips 52 
are pulled up from their recesses 70 and the handle assembly 50 extended. 
The pin 58 will lock into hole 60 and the joint 62 will not pivot beyond 
the line of the assembly. The wheel assembly 30 is rotated into the down 
position and the apparatus is tilted back using the wheels 32 as a 
fulcrum. 
The present invention has the advantage of allowing a user to transport a 
cooler full of material a great distance that could otherwise result in 
severe strain to the arms, legs and back if carried by hand. The wheel 
assembly 30 conveniently permits the user to shift position of the wheels 
32 without cumbersome movement of gears or levers, or undue lifting of the 
cooler to gain access to the wheel mechanism. 
While the invention has been described in connection with certain preferred 
embodiments, it is not intended to limit the scope of the invention to the 
particular forms set forth, but, on the contrary, it is intended to cover 
such alternatives, modifications, and equivalents as may be included 
within the spirit and scope of the invention as defined by the appended 
claims.