Abstract:
A self-propelled, remote-controlled utility cart of the present invention overcomes the disadvantages of present utility cart designs. Through the combination of a utility cart with a drive mechanism and a steering mechanism, the utility cart of the present invention can be used in circumstances in which typical, manual manipulation of the utility car is difficult if not impossible for the average homeowner. In one embodiment, the self-propelled, remote-controlled utility cart takes the form of an ice chest. The combination of an insulated cooler design with a drive mechanism and steering mechanism such that the ice cooler is self-propelled effectively eliminates any hand-carrying requirements which is especially advantageous when the insulated cooler is fully loaded with food and beverages. The utility cart of the present invention further includes a control assembly allowing for remote operation of the drive and steering mechanisms by the user.

Description:
RELATED APPLICATIONS AND PRIORITY CLAIM  
       [0001]     The present invention claims priority to U.S. Provisional Application No. 60/408,449 entitled, “REMOTE/RADIO CONTROLLED, SELF-PROPELLED ICE CHEST,” filed Sep. 5, 2002, and U.S. Provisional Application No. 60/423,942 entitled, “REMOTE/RADIO CONTROLLED, SELF-PROPELLED ICE CHEST,” filed Nov. 5, 2002, both of which are hereby incorporated by reference in their entirety. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates generally to the field of portable utility carts such as portable ice coolers. More specifically, the present invention relates to a steerable, self-propelled utility cart for home use including a control apparatus for remote operation and direction of the utility cart&#39;s drive and steering mechanism.  
       BACKGROUND OF THE INVENTION  
       [0003]     Homeowners have many options when it comes to the use of utility carts for residential improvement projects or for miscellaneous odd jobs around the house. Utility carts can be used to transport dirt, sod, landscaping bricks or firewood. Another popular use is in transporting or holding items, such as food or beverages, necessary for entertaining guests.  
         [0004]     Regardless of the use, most utility cart designs include some form of handle assembly allowing the user to manually direct the utility cart from one location to the next. Depending on the type of function the utility cart is performing, the load will often be heavy requiring a great deal of exertion on the part of the user. In some cases, the weight of the load may exceed the strength of the user such that manual transport of the utility cart is effectively impossible. An example of such a situation is when the utility cart takes the form of a portable ice chest and is filled with items such as ice, food and beverages.  
         [0005]     Portable ice chests or “coolers” are well known by consumers and are frequently used in a wide variety of recreational settings such as camping, sporting events or for spare storage when a household freezer or refrigerator is full. Examples of typical ice chests or coolers include those manufactured by The Coleman® Company (http://www.coleman.com) and the Igloo® Products Corp. (http://www.igloocoolers.com). These coolers can range from small, hand carriable units for soft-drinks all the way to large, wheel borne coolers for transporting large amounts of food or beverages or even for storing freshly caught fish.  
         [0006]     In use, a user will most typically place the food or beverage items which they desire to keep cold within the insulated interior of the ice chest. A cooling means such as ice cubes, ice blocks or refreezable, artificial ice packs are also placed within the interior of the ice chest and the cover is then closed. The combination of the cooling means with the insulated interior keeps the beverages or food items in a cooled state.  
         [0007]     While current cooler designs are meant to be easily transportable, often the amount of food and beverages within the cooler makes them unwieldy and difficult, if not impossible, for a single user to carry. As such, it would be desirable to have a cooler that provides an individual user with the ability to more easily transport a cooler that is heavily laden with food and beverages.  
       SUMMARY OF THE INVENTION  
       [0008]     The self-propelled, remote-controlled utility cart of the present invention overcomes the disadvantages of present utility cart designs. Through the combination of a utility cart with a drive mechanism and a steering mechanism, the utility cart of the present invention can be used in circumstances in which typical, manual manipulation of the utility car is difficult if not impossible for the average homeowner.  
         [0009]     With specific reference to an embodiment of a utility cart taking the form of an ice chest, the combination of an insulated cooler design with a drive mechanism and steering mechanism such that the ice cooler is self-propelled effectively eliminates any hand-carrying requirements which is especially advantageous when the insulated cooler is fully loaded with food and beverages. The utility cart of the present invention further includes a control assembly allowing for remote operation of the drive and steering mechanisms by the user. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is an embodiment of a self-propelled, remote-controlled utility cart of the present invention.  
         [0011]      FIG. 2  is a perspective view of a self-propelled, remote-controlled ice chest assembly of the present invention.  
         [0012]      FIG. 3  is a perspective view of an ice chest of the present invention in an open disposition.  
         [0013]      FIG. 4  is a sectional view of the ice chest of  FIG. 2 .  
         [0014]      FIG. 5  is a top view of the ice chest of  FIG. 2  in an open disposition.  
         [0015]      FIG. 6  is a top view of the ice chest of  FIG. 2  in an open disposition.  
         [0016]      FIG. 7  is a bottom view of a steering mechanism.  
         [0017]      FIG. 8  is a bottom, perspective view of a wheel assembly.  
         [0018]      FIG. 9  is a bottom, perspective view of a drive mechanism.  
         [0019]      FIG. 10  is a side view of a control instrument.  
         [0020]      FIG. 11  is an embodiment of a self-propelled, remote-controlled ice chest assembly of the present invention.  
         [0021]      FIG. 12  is a flow chart depicting a control method for the remote-controlled ice chest assembly of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]     A self-propelled, remote-controlled utility cart  70  of the present invention is depicted in  FIG. 1 . Generally, utility cart  70  comprises a body  72  having a plurality of wheels  74 , a steering mechanism  76 , a drive mechanism  78 , a power supply  80 , a receiver  82  and a control device  84 . Control device  84  may be directly wired to steering mechanism  76  and drive mechanism  78  with a length of control wire  85 . Alternatively, control device  84  can utilize a wireless protocol, such as radio frequency or infrared, to communicate with the receiver. Utility cart  70  can also comprise a manual handle  86  to allow for manual direction of the utility cart  70 . Typically, body  72  includes a loading floor  88  and may comprise side walls  90 . Below loading floor  88  is a mounting floor  92  for mounting components associated with steering mechanism  76 , drive mechanism  78 , power supply  80  and receiver  82 .  
         [0023]     As depicted in  FIG. 2 , an embodiment of a self-propelled, remote-controlled utility cart  100  of the present invention comprises an ice chest assembly  102  and a wireless control device  104 . Ice chest assembly  102  comprises an ice chest  105  having an insulated body  106  and an insulated cover  108 . Insulated body  106  defines a front wall  110 , a rear wall  112 , a pair of side walls  114   a,    114   b  and a bottom surface  116 . To facilitate lifting of the ice chest assembly  102 , a pair of handles  118   a,    118   b  can be located on the front wall  110  and rear wall  112 . Ice chest assembly  102  also includes a pair of drive wheels  120   a,    120   b  and a pair of steering wheels  122   a,    122   b.  Ice chest assembly  102  is further depicted in an open disposition in  FIG. 3 . An interior storage space  124  is defined by front wall  110 , rear wall  112 , side walls  114   a,    114   b,  bottom surface  116  and insulated cover  108 . As shown in  FIG. 4 , interior storage space  124  is divided into a refrigerated space  126  and a component mounting space  128  by an insulated sealing floor  130 . Sealing floor  130  interacts with a perimeter seal  132  and a perimeter bracket  134  to prevent leakage, most typically water from melted ice, from the refrigerated space  126  into the component mounting space  128 .  
         [0024]     As shown in  FIGS. 5 and 6 , ice chest assembly  102  includes a drive assembly  136 , a steering assembly  138 , a power source  140  and a receiver  141  mounted within the component mounting space  128 . Drive assembly  136  comprises a first motor  142 , a second motor  144 , an electrical switch  146 , a pair of timing belt pulleys  148   a,    148   b  and a timing belt  150 . Preferably, first motor  142  is a rotational DC gear motor while second motor  144  is a rotational servomotor. In an alternative configuration, drive assembly  136  can be configured as a direct drive gear system. Steering assembly  138  comprises a third motor  152  and a linkage assembly  154 . Preferably, third motor  152  is a rotational servomotor. As depicted, power source  140  comprises a battery  156  wired to power both the drive assembly  136  and steering assembly  138 . Power source  140  also includes an on/off switch to cut power from the battery  156  to the other components. Preferably, battery  156  comprises a DC rechargeable battery. In alternative arrangements, power source  140  can comprise other power options, either alone or in combination with a battery system, such as solar powered, fuel cells and internal combustion engines. For example, an internal combustion engine can separately power the drive assembly  136  while a battery system powers the steering assembly  138 . Receiver  141  most typically takes the form of a wireless receiver, for example a two-channel radio frequency receiver. Receiver  141  is capable of converting a digital input signal from control device  104  to a proportional signal for controlling the second motor  144  and the third motor  152 .  
         [0025]     Steering assembly  138  is more clearly depicted in  FIGS. 7 and 8 . Steering assembly  138  comprises a connecting arm  158  operably connecting the third motor  152  and one of the steering wheels  122   b.  As depicted, each steering wheel  122   a,    122   b  is mounted on its own axle  160   a,    160   b  which is correspondingly mounted within an axle sleeve  162   a,    162   b,  each including a bearing  164   a,    164   b.  Axle sleeve  162   b  is fixedly attached to a steering arm  166 . Axle sleeves  162   a,    162   b  are also fixedly attached to a pair of linking arms  168   a,    168   b.  Linking arms  168   a,    168   b  are connected with a connecting rod  170  with a pair of connecting pins  172   a,    172   b.  Connecting arm  158  projects through a steering aperture  174  in the front wall  110  of ice chest  105 . As depicted, a drain plug  176  is also shown in front wall  110 .  
         [0026]     As depicted in  FIG. 9 , drive assembly  136  comprises a drive axle  180 , a pair of axle mounts  182   a,    182   b  including a pair of axle bearings  184   a,    184   b  and a drive pulley  186 . Timing belt  150  extends through a drive slot  188  in bottom surface  116  and wraps around drive pulley  186  such that drive assembly  136  and first motor  142  are operably connected. Drive assembly  136  may include a spring suspension for mounting drive axle  180  to reduce the effects of uneven ground.  
         [0027]     An embodiment of control device  104  is illustrated in  FIG. 10 . Control device  104  includes controller body  190  including a hand grip  192  and a battery storage compartment  194 . Control device  104  further comprises an antenna  196 , a remote wheel  198  and a throttle lever  200 . Most preferably, control device  104  transmits digital proportional signals over the two channels via a wireless protocol such as radio frequency or infrared. An example of a suitable control device  104  includes those manufactured by the Futaba® Company. For example, the Futaba® Models 2PH &amp; 2PHKA controllers are two-channel radio frequency controllers that are envisioned for use with the self-propelled, remote-controlled utility cart  100  of the present invention. Alternatively, a control device  184  including a length of control wire  85  similar to that illustrated in  FIG. 1  could be used to communicate directly with the drive assembly  136  and the steering assembly  138 .  
         [0028]     An alternative embodiment of an ice chest assembly  202  is depicted in  FIG. 11 . Ice chest assembly  202  is comprised of an insulated body  204  and an insulated cover  206 . Insulated cover  206  can be hingedly attached or include means for slidably inserting into the insulated body  204 . As depicted, insulated body  204  includes an insulated storage space  208  and a separate and distinct mounting space  210 . Preferably, insulated body  204  is integrally molded such that a storage floor/mounting roof  212  prevents any possibility of leaking, such as water from melting ice, from the insulated storage space  208  into the mounting space  210 . Using mounting space  210 , drive assembly  136 , steering assembly  138  and power source  140  are wired and mounted to insulated body  204 . Insulated body  204  further includes a manual handle  214  allowing a user to pull the ice chest assembly  140  in appropriate situations.  
         [0029]     In actual use, the self-propelled, remote-controlled utility cart  100  is most typically loaded with a combination of ice and food and/or beverages. With respect to ice chest assembly  102 , a user must first sealingly install sealing floor  130  within interior storage space  124  to prevent potential water damage to components comprising the drive assembly  136 , the steering assembly  138 , power source  140  and receiver  141 .  
         [0030]     Once the self-propelled remote-controlled utility cart  100  has been loaded, a user can remotely direct the utility cart  100  through manipulation of the control device  104 . As illustrated in  FIG. 12 , control device  104  comprises a remote control unit having at least two separate controls channels, for instance first channel  220  and second channel  222 . First channel  220  and second channel  222  are used to provide radio frequency communication between the control device  104  and the receiver  141  within the ice chest assembly  102 . Control device  104  typically operates at a radio frequency range of 27 MHz, 50 MHz, 72 MHz or 75 MHz. For a control device  104  operating at 75 MHz, first channel  200  could correspond to 75.410 MHz while second channel  222  could correspond to 75.430 MHz. In the present invention, first channel  220  is used to communicate user inputs from the throttle lever  200  to the second motor  144  of the drive assembly  136  while the second channel  222  is used to communicate user inputs from the remote wheel  198  to the third motor  152  of the steering assembly  138 . Alternatively, control device  104  can transmit control signals via alternative wireless protocols such as an infrared signal.  
         [0031]     With respect to drive assembly  136 , a user depresses throttle lever  200  causing a digital signal to be transmitted to receiver  141  over first channel  220 . Receiver  141  converts the digital signal to a proportional signal which subsequently controls the second motor  144 . Second motor  144  is linked to a speed controller such that when the second motor  144  turns in one direction, positive DC voltage is applied to the first motor  142  and when the second motor  144  turns in the opposition direction, negative DC voltage is applied to the first motor  142 . Timing belt  150  is coupled to the first motor  142  at one end and to the drive pulley  186  at the other end. As motor  142  causes timing belt  150  to turn, drive pulley  186  is forced to rotate such that drive axle  180  turns and drive wheels  120   a,    120   b  cause ice chest assembly  102  to be propelled forward or backward depending upon the DC voltage applied to the first motor  142 .  
         [0032]     With respect to steering assembly  138 , a user turns the remote wheel  198  causing a digital signal to be transmitted to receiver  141  over second channel  222 . Receiver  141  converts the digital signal to a proportional signal which subsequently controls the third motor  152 . Third motor  152  is linked to the connecting arm  158  such that when the second motor  144  turns, connecting arm  158  causes steering arm  166  to move in a left or right direction. As steering arm  166  moves, the steering wheels  122   a,    122   b  are directed in the desired direction through the interconnection of the linking arms  168   a,    168   b  and the connecting rod  170 . Through the combination of the drive assembly  136 , steering assembly  138  and control device  104 , a user can remotely direct the movement of the self-propelled, remote-controlled utility cart  100  as desired.  
         [0033]     Although various embodiments of the present invention have been disclosed here for purposes of illustration, it should be understood that a variety of changes, modifications and substitutions may be incorporated without departing from either the spirit or scope of the present invention.