Abstract:
A compact battery powered mover for heavy rollable loads, having a ventilated battery compartment incorporated into the body of the mover and a removable rechargeable ventilated battery that permits the replacement of a spent battery with a fresh battery at the work location. The mover also has incorporated into its compact design a motor controller that enables the use of a heavy current draw when needed for brief periods without developing excessive heating. The configuration of the critical components in and on the mover body permits the substitution of one critical component with another component having different operating properties without significantly changing the compactness of the mover.

Description:
BACKGROUND OF THE INVENTION 
   This invention relates to roll movers for moving large heavy rolls of materials and other heavy rollable loads, and more specifically to roll movers which are compact in size and powered by removable and rechargeable batteries. 
   Surface drive movers of the type wherein a driven roller engages a rolling surface of a vehicle wheel or a roll of material to be moved have long been known in the art. These movers typically receive their energy through an attached electrical cord or a hydraulic or air hose. In use, the movers require long lengths of hose or cord and consequentially the movers suffer from the problems and hazards associated with having long cords or hoses dragged over the surface of a work area. 
   Industry has long desired but heretofore not achieved a compact battery powered surface drive roll mover for moving heavy rolls of material such as paper, plastic and metal. There have been earlier attempts at providing battery powered roll movers for use in moving large heavy rolls of materials. Those attempts have not been completely successful due to problems related to the high energy requirements over short periods of time that are associated with moving large heavy rolls of material. 
   A second set of unmet conditions for a successful battery powered surface drive roll mover are related to size limitations imposed by the limited amount of space under two rolls that are in contact with each other. A successful battery powered surface drive roll mover must be able to be inserted underneath two rolls in contact with each other and turned to engage the roll to be moved. 
   A third unmet set of conditions for a successful battery powered surface drive roll mover are related to the range of weights found in rolls of the same size but of differing materials. A heavy roll of paper that is eight feet long and three feet in diameter will typically weigh approximately one ton. The same size very heavy roll of copper foil will weigh more than fifteen tons. A successful surface drive roll mover for moving very heavy rolls will have the same size restrictions as those for heavy rolls, but significantly different power and component requirements. 
   Early applications of such friction drive apparatus were to move wheeled vehicles such as airplanes, train cars, trailers and the like in difficult to maneuver locations such as parking, repair, and storage areas. 
   U.S. Pat. No. 2,432,156 to Hill (1947), discloses a friction drive for moving rollable loads which employs a mover configured to be positioned under large diameter wheels of heavy rollable loads (railroad car wheels). The mover of Hill utilizes an electrical cord as a power source. 
   U.S. Pat. No. 2,949,972 to Wirkkala (1960) discloses the earliest example of a battery powered friction drive mover of rollable loads known to the inventor. The mover was used for towing aircraft in hangers and repair facilities. 
   U.S. Pat. No. 4,582,154 to England discloses a friction drive for moving rollable loads (vehicles) that is powered by an electrical, pneumatic or hydraulic motor which receives its energy through a cable or hose in the handle. 
   As industry develops larger and heavier rolls, there is a tendency to require greater and greater performance capabilities of a roll mover unit. Heretofore, units that were challenged beyond their performance capabilities simply stalled out, heated up, or broke down. 
   Heretofore, the prior art has not provided a compact battery powered mover for moving heavy and very heavy rolls of materials such as paper, plastic and metal. More specifically, the prior art does not provide a friction-drive heavy roll mover of the type disclosed hereinafter powered by a small, light weight, air cooled, removable, rechargeable battery carried on the roll mover body that can deliver the power required to move a heavy roll of material. 
   Still more specifically, the prior art does not provide the compact battery powered roll mover as described above wherein the battery is a ventilated battery and the battery compartment is ventilated. 
   Still more specifically, the prior art does not provide the compact battery operated heavy roll mover as described above wherein the mover can be configured to have significantly different operating characteristics by modifying the critical components of the mover without significantly changing the compact size of the mover. 
   BRIEF SUMMARY OF THE INVENTION 
   The invention provides a compact battery-powered surface drive roll mover comprising a roll mover body having a front end, a back end, a first side and a second side, a top, and bottom; at least one floor engaging roller deployed across the front-bottom end of the body and at least one roll engaging roller deployed across the front-top end of the body and the floor engaging roller and the roll engaging rollers are driven to rotate in opposite directions at approximately the same surface speed; at least one wheel mounted on the body at the back end of the body; a battery compartment located inside the body; a direct-current motor mounted on the first side of the body and a gear assembly mounted between the first side and the second side of the body and the motor drives the gear assembly and the gear assembly drives the roll engaging roller, and the gear assembly has a reduction capability of at least 20:1; a rechargeable, light weight, battery that is readily placed in and removed from the battery compartment and readily connected to and disconnected from an electrical coupling that feeds electricity from the battery to the electric motor and its related circuitry; an articulated handle secured to the top-center of the body and the handle projects up and away from the body towards the back end of the body and the handle is provided with an on-off switch and a motor controller operably connected to the motor and its related circuitry. 
   It is therefore an object of this invention to provide a compact battery powered heavy roll mover that is powered by a small, light weight rechargeable battery that is removable from the unit at the job site and replaceable with a charged battery, thereby obviating the removal of the unit from service to recharge the battery. 
   Further, it is an object of this invention to provide a roll mover as described above wherein the roll mover is provided with electrical circuitry that protects the mover from overheating when operated at a preset maximum current draw for short periods of time and will shut the unit down if temperatures exceed a preset limit. 
   It is further an object of this invention to provide the roll mover described above wherein the critical components of the roll mover can be changed to meet the requirements for moving rolls of specific materials without increasing the size of the unit appreciably. 
   Specifics of how these and other objectives are met by this invention will be made apparent from the following specifications, drawings, and appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side elevation view of a preferred configuration of the roll mover of this invention engaged with a roll to be moved. 
       FIG. 2  is a perspective view of the roll mover of  FIG. 1 . 
       FIG. 3  is a side elevation view of the roll mover of  FIG. 1  inserted under two rolls that are in contact with each other. 
       FIG. 4  is a perspective view of the roll mover of  FIG. 1  illustrating the alternative positions for the articulated handle of the mover. 
       FIG. 5  is a wiring diagram for the roll mover of  FIG. 1 . 
       FIG. 6  is schematic representation of the physical arrangement of the critical components of the mover of  FIG. 1 . 
       FIG. 7  is an exploded view of the roll-engaging roller assembly. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the drawings like numbers refer to like objects, the proportions of some components have been modified, and some non-critical components have been omitted for clarity of illustration. 
   The term “heavy roll” as used herein shall be read to mean rolls weighing 1,000 pounds or more. 
   The term “ventilated battery” as used herein shall be read to mean a battery wherein the cells of the battery are separated to permit air to circulate between the cells and two opposite sides of the battery are open to permit air to flow through the battery. 
   The term “small space” as used herein shall be understood to mean “of a size that can readily be inserted between and under two heavy rolls that are in contact with one another.” 
   The term “compact” as used herein shall be understood to mean “closely and neatly packed together, having all the necessary components or features neatly fitted into a small space.” 
   Referring now to  FIGS. 1 through 4 , a preferred embodiment of this invention is shown. Battery powered roll mover  1  has a roll mover body  2  having a front end  3 , a back end  4 , a first side  5  and a second side  6 , a top  7 , and a bottom  8 . At least one floor-engaging roller  10  is deployed across the front-bottom end of the body and at least one roll-engaging roller  11  deployed across the front-top end of the body. The floor engaging-roller  10  and the roll-engaging roller  11  are driven to rotate in opposite directions at approximately the same surface speed. At least one and preferably two back wheels  12  are rotabably mounted on the body  2  at the lower-back end of body  2 . A ventilated battery compartment  13  is located inside body  2 . A motor  14 , preferably direct-current motor, is mounted within the body  2 , preferably on the first side  5  of body  2 , and a roller drive assembly  18  is also mounted within the body  2 , preferably on second side  6  of body  2 . A gear reducer  19  is also located inside body  2 , and is connected between motor  14  and roller drive assembly  18 . Motor  14  thereby drives the gear reducer  19  and the gear reducer drives roller drive assembly  18 . Roller drive assembly  18  in turn drives roll engaging roller  11 . In the most preferred embodiment, the gear reducer  19  has a reduction of at least 20:1, so as to drive floor engaging roller  10  and the roll engaging roller  11  at a high torque and at a low revolution per minute rate, since motor  14  is therefore turning at least twenty times the rate of the roll engaging roller  11 . The embodiments shown in the figures also provide a rechargeable ventilated battery  16  that is readily placed in and removed from battery compartment  13 . Battery  16  may be composed of any suitable quick charge battery cells, including nickel-cadmium and nickel-metal-hydride as well as other types of suitable quick charge battery cells. Battery  16  is readily connected to and disconnected from an electrical coupling  17  that feeds electricity to the electric motor  14  and its related circuitry, as will be explained subsequently. A handle  20  is secured to body  2 , preferably at the top of the body in front of battery compartment  13  and behind roll engaging roller  11 . Handle  20  projects upward and rearward from body  2  in the direction of back end  4 . Handle  20  is provided with at least an on-off switch  21 , and preferably also a motor control throttle  22 . 
   In the embodiment shown in  FIGS. 1 and 2 , body  2  has two floor engaging rollers  10 . Each floor-engaging roller has its axle  30  mounted in a respective slot  31 . This mounting arrangement permits rollers  10  to maintain frictional engagement with roll-engaging roller  11  as the rollers wear and to transmit loads directly from roll-engaging roller  11  through floor-engaging rollers  10  to the floor. While one floor-engaging roller  10  will serve, two rollers  10  are preferred. 
   In the drawings, roll mover  1  is shown to be provided with two back wheels  12 . While a single back wheel or a roller will serve, the use of two wheels as shown is preferred because it provides more stability and maneuverability when the weight of roll mover  1  is transferred to the back wheels so that roll mover  1  can be wheeled around without the use of power. 
   Referring now to  FIGS. 1 ,  5  and  6 , ventilated battery  16  has cells  33  which are spaced apart from each other so that air can flow around and between the cells, and open ends  34  of battery case  36  will permit air to flow freely through battery case  36 . Air is permitted to enter ventilated battery compartment  13  through vents (not shown) in compartment  13  and to flow through battery  16 . Roll mover  1  is provided with a quick release connector  37  that engages with electrical coupling  17  which serves to transfer electricity to a motor controller  39  or to connect battery  16  to a charger. A non-ventilated battery in a non-ventilated battery compartment will serve, but a ventilated battery and a ventilated compartment are preferred. 
   Referring now to  FIGS. 5 and 6 , which show the electrical components of mover  1 , motor controller  39  is shown connected between the motor  14  and the battery  16 . In this embodiment, motor controller  39  serves two critical functions that are related to the high energy demands for short periods of times and essential to a successful compact battery powered heavy roll mover. The first is related to the heating of the battery  16 , the motor  14  and the motor controller  39 . The second is related to delivering full power in short bursts to the roll contacting roller  11  at times of maximum demand to overcome static inertia while avoiding overheating of the electrical components of mover  1 . 
   The static inertia of a roll requires more power to overcome than the power required for increasing or maintaining the dynamic inertia of the roll. Accordingly, to get a roll moving, a high power draw capability is provided to roll mover  1  for a short interval. The high power draw results in heat build up in ventilated battery  16 , in motor  14 , and in motor controller  39 . To deal with the high current draws needed to overcome the static inertia of heavy rolls, in the most preferred embodiment motor controller  39  includes a pulse width modulation component  43  which will detect when a preset maximum current draw has been reached, at which time pulse width modulator  43  begins to interrupt and reestablish the high current flow rate at short intervals, thereby providing the power needed to get a heavy roll moving, while at the same time slowing the rate of heat buildup in motor  14  and ventilated battery  16 , and motor controller  39  itself. In a preferred embodiment, the motor controller  39  has the additional capability of shutting off the unit in the event of overheating. Alternatively or in addition, conventional overheat thermal switches (not shown) may also be included to interrupt power to the unit if a preset overheat temperature is reached. 
   The space beneath and between two rolls that are in contact with each other places limitations on the size of a roll mover  1  that can be inserted under the gap between the rolls to move one roll away from the other roll. The short term current flow required to overcome static inertia in a heavy roll requires a current limiting system and overheat protection. Prior art attempts to provide a battery powered roll mover for heavy rolls have been unsuccessful due in part to their inability to reduce battery size while providing the current delivery capabilities required to get a heavy roll moving without overheating the critical components of the system. The roll mover of this invention meets those requirements. 
   Referring now to  FIGS. 3 and 4 , the criticality of the compactness of the design of mover  1  and how it cooperates with articulated handle  20  to permit mover  1  to be inserted under two rolls in contact with each other is shown. Handle  20  in  FIG. 4  is shown in position for left hand insertion under the roll to be moved  47  and roll  46 . Handle  20  is joined to pivot  44  about which handle  20  may be pivoted into position  45  (shown dashed) for right hand insertion under rolls  46  and  47 . Handle  20  may also be pivoted into position  50  (shown dashed) for guiding mover  1  when mover  1  is positioned in the middle of the roll to be moved. 
   Rolls of differing materials such as rolls of paper, plastic, and metal, have significantly different weights and surface properties. Further, roll contacting roller  11  transmits the energy to move a heavy or very heavy roll and is subject to heavy loading and significant wear. It is therefore critically important that roll contacting roller  11  be readily, quickly and conveniently exchangeable with another roller  11 , which may be made of a different material or have a different kind of surfacing. For example: the surface of roller  11  can be of rubber, plastic, composite material, or metal. Its surface may be smooth or rough or grooved or knurled. The invention includes any suitable mounting of the roll-contacting roller  11  to the body  2 , that satisfies these conditions. Preferably, referring now to  FIGS. 1 and 2  and  7 , for the sake of strength given the heavy loads to be encountered, roll engaging roller  11  is mounted to first side  5  and second side  6  of mover body  2  by mounting screws  23  passing through bearings  32  to secure bearings  32  to roll mover body  2 . When it is desired to remove and replace roll engaging roller  11 , screws  23  are removed and roller  11  is lifted out of slots  24  of sides  5  and  6  in which axle  9  of roller  11  resides A replacement roll engaging roller  11  may then be assembled and attached to body  2  by reversing the disassembly steps. 
   A typical work environment for the roll mover of this invention is one wherein heavy rolls are moved away from roll forming machines, or to roll consuming machines. 
   The following example discloses design values for a general utility roll mover and presents a single set of values in the ranges of values that are within the scope of this invention. 
   EXAMPLE 
   A typical paper roll mover  1  capable of moving a roll weighing 5000 pounds had a ventilated battery having twenty 1.2 volt nickel-cadmium cells and had the capacity to deliver 24 volts at 80 amps. The battery had outside dimensions of about 4.5 inches by 5.5 inches by 2.2 inches and would weigh on the order of about 4 pounds. The dimensions of the body of the roll mover were about 11.2 inches wide at its widest point, 7.3 inches high, and 14.9 inches long. 
   The motor drew 30 amps at 24 volts when a heavy roll was being rolled. 
   The gear assembly produced a 40:1 reduction in rpm. 
   The roll engaging roller had an 85A durometer plastic or rubber coating and was mounted in heavy duty bearings that can be detached from mover  1  for easy replacement. 
   The roll mover has a maximum floor speed of approximately 120 feet per minute. 
   The above disclosures and the example cited are enabling and would permit one of ordinary skill in the art to make and use the invention for its intended purposes without undue experimentation. The inventor has shown that the critical elements of his compact battery powered roll mover are its compactness, a ventilated battery that is removable and rechargeable, and overheat protection. 
   It should be understood that the roll mover of this invention can be applied to tasks such as those taught by the prior art cited above. It also should be understood that it is a part of this invention to provide a compact battery operated roll mover of the type disclosed above that can be configured for application to specific tasks without departing from the basic concept of the invention or appreciably increasing the compact size of the invention. 
   It has been previously disclosed that rolls of the same diameter but of different materials will have significantly different weights and significantly different performance requirements for a roll mover, while still presenting the same need for compactness. The typical components of the heavy roll mover  1  recited in the above example can each be upgraded to meet the performance requirements for moving very heavy rolls without significantly changing the compactness or size of mover  1 . 
   Referring now to  FIGS. 1 through 6 , ventilated battery compartment  13  can be extended in the direction of back end  4  to form extended ventilated battery compartment  52  shown dashed in  FIGS. 1 and 3 . The addition of compartment  52  will not interfere with the turning of mover  1  beneath two rolls in contact with each other. Compartment  52  permits the doubling of the size of battery  16 . The horsepower of motor  14  can be increased with only small increases in the size of the motor housing. The motor controller  39  can be replaced with a motor controller having a different set of power requirements, and even different characteristics, without significantly changing the size of the motor controller. The motor controller  39  can even be programmable, permitting the setting and changing of characteristics without removal. In that event, such parameters as top speed and the ramp slopes for acceleration and deceleration can even be changed. Further, the gear ratio of the gears in gear box  19  can be changed without changing the size of gear box  19 . As previously disclosed, roll engaging roller  11  can be exchanged for a roller  11  with different surfacing or other properties without changing the size of roller  11 . 
   In general, as the weight of the roll goes up, the speed at which the roll can be safely moved goes down because of the inertia of the heavier roll. The above changes in the components of the typical heavy roll mover  1  of the above example permit the conversion of the typical heavy roll mover to a roll mover for very heavy rolls without appreciably modifying the critical compactness of mover  1 . 
   A preferred embodiment of the invention has been disclosed above and it has been shown that numerous variants of the invention can be made without departing from the scope of the invention. Therefore, it should be understood that the scope of this invention should not be limited to the scope of the embodiments disclosed but the scope should also include those variants thereof that would be made apparent thereby to one skilled in the art.