Patent Publication Number: US-2009223729-A1

Title: Power-driven device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from and the benefit of U.S. Provisional Application No. 61/068,741 entitled UTILITY CART PROPELLED BY STRING TRIMMER POWER HEAD, filed Mar. 10, 2008, which is hereby incorporated by reference in its entirety and U.S. Provisional Application No. 61/124,489 entitled UTILITY CART PROPELLED BY STRING TRIMMER POWER HEAD, filed Apr. 18, 2008, which is hereby incorporated by reference in its entirety. 
    
    
     FIELD 
     The present disclosure generally relates to a power-driven device and method for powering a power-driven device. In particular, the present disclosure relates to a modular device having a drive interface configured for releasably rotatably communicating with a motor-driven flexible drive shaft. 
     BACKGROUND 
     Hauling loads has long been a task performed by individuals. Wheelbarrows, carts, and hand trucks have long been used to facilitate hauling loads. Generally these devices include a hauling portion and an operator portion. The hauling portion carries the load and the operator portion is controlled by the operator. These devices assist individuals in hauling loads that would not otherwise be too heavy or too awkward. However, the loads can remain too heavy for many people to handle. In addition, repetitive hauling of the loads can result in health problems and/or physical stress. Similarly, for example, mowing lawn, snow-blowing, aerating lawn, spreading substances on lawns or other areas may result in health problems and/or physical stress. Often, each of these tasks is performed by a different device. This results in individuals purchasing and storing numerous tools to perform separate tasks. 
     Generally, motorized devices can aid in the above tasks. Motorized devices can include a hauling portion similar to those in wheelbarrows, carts, and hand trucks. Motorized hauling devices typically include a permanently installed motor. Having a permanent motor can result in motorized hauling devices being heavy and expensive. For example, the cost of the motorized hauling device may include the cost of the hauling portion, the cost of the operator portion, and the cost of the motor. In addition, the motor is difficult and expensive to maintain and repair. Electric motorized hauling devices can require recharging and/or may have power limitations. 
     Motorized hauling devices having permanently installed motors typically include a motor mounted near the ground. Positioning the motor near the ground can increase risk of contaminants entering the motor and/or prevent operation in shallow water. Positioning the motor near the ground can also result in more weight being distributed on the hauling portion of the motorized hauling device. In addition, positioning the motor near the ground can require additional features and/or equipment to permit control of the motor at the operator portion of the motorized hauling device. 
     What is needed is a device having improved capability of providing power and/power assistance for performing a plurality of tasks, having decreased production costs, is easily maintained and repaired, is lightweight and includes improved operational features. 
     SUMMARY OF THE DISCLOSURE 
     One aspect of the present disclosure includes a power-driven device includes a body, at least one wheel configured to support the body, and a drive shaft in rotational communication with one or more of the at least one wheel, the drive shaft being in rotational communication with a drive interface, the drive interface being configured to releasably rotatably communicate with a motor-driven flexible drive shaft. 
     Another aspect of the present disclosure includes a gas-powered device includes a body for hauling, at least one wheel configured to support the body, and a drive shaft in rotational communication with one or more of the at least one wheel, the drive shaft having a drive interface, the drive interface being configured to releasably rotatably communicate with a motor-driven flexible drive shaft. In the embodiment, the drive interface is further configured to releasably rotatably communicate with the motor-driven flexible drive shaft by manual engagement, the motor-driven flexible drive shaft is a disengaged portion of a rotary cutting assembly, and the motor-driven drive shaft is configured to be rotated by a motor, the motor having a horse power of less than about five horse power. 
     Still another aspect of the present disclosure includes a method of powering a device includes providing a body, providing at least one wheel configured for supporting the body, providing a drive shaft in rotational communication with one or more of the at least one wheel, the drive shaft having a drive interface, the drive interface being configured to releasably rotatably communicate with a motor-driven flexible drive shaft of a disengaged portion of a rotary cutting assembly, and manually inserting the disengaged portion of the rotary cutting assembly into the drive interface, thereby placing the motor-driven flexible drive shaft in rotational communication with the drive interface. 
     One advantage of the present disclosure includes the ability to provide power to assist in moving a device that does not include a permanently installed motor. 
     Another advantage of the present disclosure includes using a motor from another device, which is easily removed for repair and/or maintenance. 
     Another advantage of the present disclosure includes the ability to operate the device in conditions, such as shallow water. 
     Another advantage of the present disclosure includes a lightweight device that is easily stored and/or transported. 
     Other features and advantages of the present disclosure will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a rotary cutting assembly. 
         FIG. 2  shows a sectional view of the rotary cutting assembly of  FIG. 1 . 
         FIG. 3  shows a sectional view of the rotary cutting assembly of  FIG. 1  in a detached configuration. 
         FIG. 4  shows a top view of the device according to one embodiment of the disclosure. 
         FIG. 5  shows a top view of the device according to another embodiment of the disclosure. 
         FIG. 6  shows a top view of the device according to another embodiment of the disclosure. 
         FIG. 7  shows a top view of the device according to another embodiment of the disclosure. 
         FIG. 8  shows a right side view of the device according to the embodiment of  FIG. 7 . 
         FIG. 9  shows a left side view of the device according to the embodiment of  FIG. 7 . 
         FIG. 10  shows a top view of the device according to another embodiment of the disclosure. 
         FIG. 11  shows a right side view of the device according to another embodiment of the disclosure. 
     
    
    
     Wherever possible, the same reference numbers will be used throughout the drawings to represent the same parts. 
     DETAILED DESCRIPTION 
       FIG. 1  shows a rotary cutting assembly  12 . The rotary cutting assembly  12  can include a motor  13 , a casing  14 , and a cutting element  15 . Motor  13  can be connected to cutting element  15  by a drive shaft (not shown in  FIG. 1 ) enclosed by casing  14 . Motor  13  can be any suitable gas or electric motor configured for converting a stored power source or fuel into rotational movement of the drive shaft. Motor  13  can include variable speeds, quiet operation features, manual throttle, bidirectional capability, and/or other suitable features. In one embodiment, motor  13  may have a horse power of five horse power or less, between one horse power and five horse power, two or less horsepower or one or less horsepower. By manipulating casing  14 , an operator  11  can position rotary cutting assembly  12  to cut desired areas of vegetation or other suitable areas. 
     Referring to  FIGS. 1 and 2 , the drive shaft in the rotary cutting assembly  12  can be a flexible drive shaft  21 . Flexible drive shaft  21  can be rotated by motor  13 . Flexible drive shaft  21  can include a coupling portion  22  configured to couple a first portion  23  to a second portion  24 . Second portion  24  can be positioned on the end of flexible drive shaft  21  near cutting element  15 . In another embodiment, coupling portion  22  may be positioned within casing  14  farther from cutting element  15 . In this embodiment, first portion  23  may be connected to an additional flexible drive shaft, a rigid drive shaft, or any other suitable element configured for rotational movement. In another embodiment, coupling portion  22 , first portion  23 , and/or second portion  24  may include threaded portions. 
     Referring to  FIGS. 2 and 3 , first portion  23  of rotary cutting assembly  12  can be selectably engaged and disengaged from second portion  24 . To engage first portion  23  with second portion  24 , first portion  23  can be inserted into a coupling portion  22  of second portion  24 . Coupling portion  22  can be threaded and/or include retention features to assist engagement. To disengage first portion  23  from second portion  24 , first portion  23  can be pulled from, screwed out of, and/or otherwise removed from coupling portion  22  of second portion  24 . Upon being disengaged from second portion  24 , first portion  23  can be inserted into a drive interface  42  of a power-driven device  41  (see  FIG. 4 ). In one embodiment, engagement and/or disengagement may be performed manually with or without the assistance of tools. 
       FIG. 4  shows an exemplary embodiment of power-driven device  41 . Device  41  can include a body  43 . Body  43  can be a substantially planar configuration of bars forming a surface for hauling loads. Body  43  can be any suitable material including, but not limited to, metals, composites, and/or wood. Body  43  may be configured for hauling loads, mowing lawns, snow-blowing, plowing, aerating lawns, and/or spreading substances (for example, seed, fertilizer, water, and/or salt). Body  43  can be supported by at least one wheel  44 . Wheel  44  can be in rotational communication with a drive shaft  45 , which may include an axel or similar structure to support and drive wheels  44 . In one embodiment, the rotational communication of wheel  44  and drive shaft  45  may be selectably engaged and disengaged by a control mechanism  51 , thereby selectively providing rotation to wheel  44 . 
     Drive interface  42  can be in selective rotational communication with drive shaft  45 . Drive interface  42  can receive a disengaged first portion  23  of rotary cutting assembly  12 . Drive interface can include coupling portion  22  and/or other suitable features permitting drive interface  42  to releasably rotatably communicate with flexible drive shaft  21 . Thus, drive interface  42  may include belts, chains, couplings, clutches or any other suitable structure that is capable of permitting flexible drive shaft  21  to be in rotational communication with drive shaft  45  and/or wheel(s)  44 . In one embodiment, drive interface  42  directly receives flexible drive shaft  21 . In another embodiment, drive interface  42  receives an intermediate feature (not shown) in rotational communication with flexible drive shaft  21 . In one embodiment, the insertion, removal, engagement, and/or disengagement can be performed manually (for example, by tightening hand screws). 
     Drive interface  42 , as shown in  FIG. 4 , includes a gear mechanism  47 , which rotates a pulley or similar device that drives a belt  52 , which rotates a sprocket or other suitable device that drives a chain  91 . The gear mechanism  47  includes any suitable mechanism capable of converting the high rotational speed of the flexible shaft  21  to a lower speed higher power. Suitable gearing may include a worm gear arrangement that rotates a pulley or other belt driving device. 
     Upon first portion  23  being engaged to drive interface  42 , device can be power-driven by motor  13 . Engagement allows flexible drive shaft  21  to rotatably communicate with drive interface  42  the drive interface and drive shaft  45 . In one embodiment, upon first portion  23  being engaged to drive interface  42 , motor  13  may be positioned distal from body  43 . This may permit operator  11  to control motor  13  and/or use the weight of motor  13  for balance. In another embodiment upon first portion  23  being engaged to drive interface  42 , motor  13  may be positioned elevated in elation to body  43 . This may provide operator  11  additional leverage, additional maneuverability, and/or the ability to used device  41  in other areas (for example, in shallow water or higher brush). 
     Referring to  FIGS. 5-11 , the device  41  can include control mechanism  51 . Control mechanism  51  can selectably engage and disengage drive shaft  45  from rotational communication with wheel  44  of body  43 . Selective engagement and disengagement can be performed by any suitable configuration. For example, selective engagement and disengagement can be performed by depressing a trigger  81 . Trigger  81  can be configured to remain depressed until a separate trigger  83  releases it (see e.g.,  FIG. 8 ). Depressing trigger  81  can rotate secondary shaft  54  by drawing a control wire  85  or other structure to rotate secondary shaft  54 . Rotation of secondary shaft  54  engages or disengages belts  52  and/or chains  91  and places drive shaft  45  and/or wheel  44  in rotational communication with flexible drive shaft  21 . For example, the rotation of secondary shaft  54  may provide increased tension between a belt  52  and one or more pulleys or other structures thereby permitting rotational communication between the flexible drive shaft  21  and drive shaft  45 . When engaged with tension, the motor-driven rotation of the flexible drive shaft  21  provides powered rotation to the wheel  44 . Released tension may permit the drive shaft to spin substantially unrestricted. Increasing the tension can also result in slowing of wheel  44  by frictional force being applied to belts  52  and/or chains  91  and/or rotating wheel  44  when flexible drive shaft  21  is not rotating, such as when the motor  13  is deactivated. The tension and release of tension by the control mechanism  51  may be assisted or driven by a spring  57  or similar device that provides a force to rotate secondary shaft  54 . 
     Referring to  FIG. 6 , device  41  is shown with first portion  23  being disengaged from drive interface  42  of device  41 . As shown, wheels  44  can be positioned within body  43 . In other embodiments more or fewer wheels  44  may be included. One or more wheels  44  may be in rotational communication with drive shaft  45 . Additionally or alternatively, wheels  44  may be positioned in a plurality of rows or other arrangements (for example, one in front and two in back). Likewise drive shaft  45  may include multiple drive shafts  45  or other structures to provide powered rotation to wheels  44 . In other embodiments, more control mechanisms  51  may be included. Additionally or alternatively, multiple motor-driven flexible drive shafts  21  may be included, thereby permitting wheels  44  to be controlled by separate motor-driven flexible drive shafts  21 . 
     Referring to  FIG. 7 , body  43  of device  41  can include attachment features  71  for receiving attachments (not shown). The attachments may be releasably attached to body permitting device  41  to be used for suitable applications as discussed above. Suitable attachments may include having structures such as snow blowing attachment structures, mowing attachment structures, lawn aerating attachment structures, spreading attachment structures, or any other attachment structure desired to be power driven. The attachment feature  71  may include opening latches, hooks, or any other structure or feature that permits mounting of attachment structures. 
     Referring to  FIG. 8 , the control mechanism  51  includes trigger  81 , which draws control wire  85  to rotate secondary shaft  54 . The secondary shaft  54  rotates and increases or decreases the tension in belt  52  in the drive interface  42 . A spring  57  provides a force to allow the wire the trigger to return to an unengaged position and to maintain tension in control wire  85 . Separate trigger  83  includes a latch or lock or feature that permits engagement and disengagement of trigger  81 . 
     Referring to  FIG. 9 , the drive interface  42  includes a gear mechanism  47 , which rotates and drives belt  52 . Control mechanism  51  includes a pulley that increases or decreases tension in the belt  52  to engage or disengage the rotational communication from the flexible drive shaft  21  to the drive shaft  45 . The belt  52  drives a chain  91 , which drives drive shaft  45 . Various gear ratios can be provided in the pulleys and belt  52  and in the chain  91  to provide desired toque for the desired applications. 
     Referring to  FIG. 10 , the device  41  includes two drive interfaces  42  for receiving motor driven flexible drive shafts  21 . In this embodiment additional control can be provided by providing selective power from each of the motor driven flexible drive shafts  21 . In addition, greater power may be provided from the dual motors  13 . Control mechanism  51  may be utilized to engage and disengage flexible drive shafts  21  together or independently. Rotation of secondary shaft  54  may be provided by any suitable technique including handles or triggers to engage or disengage the control mechanism  51 . 
     Referring to  FIG. 11 , an arrangement substantially as shown in  FIG. 8  with a payload  95  mounted on body  43 . While  FIG. 11  is shown with a payload  95 , the device  41  is not so limited and may include any suitable attachment or hauling structure. 
     While the above has been shown and described with exemplary arrangements of gearing, belts and chain configurations, the disclosure is not so limited. The drive interface may include any arrangement that provides torque conversion from the high speed of the motor-driven flexible drive shaft  21  to the drive shaft  45 . In addition, other features, such as brakes, clutches, steering or other controls may include included in the device  41 . 
     While the disclosure has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the disclosure not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this disclosure, but that the disclosure will include all embodiments falling within the scope of the appended claims.