Patent Publication Number: US-2019193493-A1

Title: Lawn mower cart

Description:
RELATED APPLICATIONS 
     The present application claims the benefit of U.S. Provisional Patent Application No. 62/608,781 to Chris Gaalema entitled “Lawn Mower Cart” and filed on December 2017, which is hereby incorporated by its reference in entirety. 
    
    
     BACKGROUND AND SUMMARY OF THE DISCLOSURE 
     Zero-turn lawn mowers have become more popular among private and commercial consumers due to their increased efficiency and speed in comparison to traditional lawn mowers. Zero-turn lawn mowers typically utilize independently controlled rear wheels rather than rear wheels that are controlled together. Each rear drive wheel of a zero-turn lawn mower is typically controlled independently with a dedicated steering handle. Independently operating the steering handles varies the magnitude and direction of torque applied to each drive wheel, which changes the speed and direction of the zero-turn lawn mower. This steering system reduces the turning radius of the zero-turn lawn mower to near zero, allowing the zero-turn lawn mower to turn substantially within its own footprint. This increases maneuverability and speed, which in turn reduces the time needed to mow a lawn. 
     Zero-turn lawn mowers have become more popular among private and commercial consumers due to their increased efficiency and speed in comparison to traditional lawn mowers. Zero-turn lawn mowers typically utilize independently controlled rear wheels rather than rear wheels that are controlled together. Each rear drive wheel of a zero-turn lawn mower is typically controlled independently with a dedicated steering handle. Independently operating the steering handles varies the magnitude and direction of torque applied to each drive wheel, which changes the speed and direction of the zero-turn lawn mower. This steering system reduces the turning radius of the zero-turn lawn mower to near zero, allowing the zero-turn lawn mower to turn substantially within its own footprint. This increases maneuverability and speed, which in turn reduces the time needed to mow a lawn. 
     One drawback to zero-turn lawn mowers is the difficulty of pulling a trailer and backing up with a trailer behind the lawn mower. Lawn mowers are sometimes used to transport loads such as lawn debris and building materials by towing a trailer behind the lawn mower. The larger turning radius of a traditional lawn mower more suitably matches most trailers, which are less capable of being reversed or backed up. However, pulling and backing up a traditional trailer with a zero-turn lawn mower can more readily cause the trailer to jackknife. This increases the difficulty of pulling and backing up a trailer behind a zero-turn lawn mower. 
     SUMMARY OF THE DISCLOSURE 
     The present disclosure relates to a cart and hitch system designed, in a preferred embodiment, to be attached to the front of a zero-turn lawn mower. In some embodiments, the cart and hitch system is designed to be attached to a drive vehicle, such as a zero-turn mower, with a hitch having two degrees of rotational freedom between the drive vehicle and the cart to facilitate turning of the drive vehicle and reduce jackknifing of the cart. More specifically, in some embodiments, the cart is allowed to rotate about the two horizontal axes of rotation relative to the drive vehicle, but is fixed along the vertical axis of rotation relative to the drive vehicle. In some embodiments, the cart has two caster wheels to facilitate the rotation of the cart about a vertical axis of rotation of the drive vehicle. 
     According to one aspect of the present disclosure, a mower and cart system is provided that comprises a mower having a mower frame, a seat supported by the mower frame, a plurality of wheels supporting the mower frame, and at least one blade supported by the mower frame and configured to cut grass. The plurality of wheels includes first and second wheels configured to power propulsion of the mower and cooperating to define a wheel axis of rotation. The system further includes a cart having a cart frame and at least one wheel supporting the cart frame and a hitch coupling the cart to the mower and defining first, second, and third axes of rotation between the mower and the cart. The first axis of rotation is parallel to the wheel axis. The second axis is vertical and a third axis is perpendicular to the first and second axes of rotation. Rotation about at least one of the first and third axes of rotation is unconstrained to allow rotational movement between the mower and the cart. Rotation about the second axis of rotation is constrained to substantially block rotational movement between the mower and the cart about the second axis of rotation. 
     According to another aspect of the present disclosure, a mower and cart system is provided that comprising a mower having a mower frame, a seat supported by the mower frame, a plurality of wheels supporting the mower frame, and at least one blade supported by the mower frame and configured to cut grass. The plurality of wheels including first and second wheels configured to power propulsion. The system further includes a cart having a cart frame and at least one wheel supporting the cart frame, and a hitch coupling the cart to the mower. The seat faces in a forward direction and the cart is positioned forward of the seat. 
     According to another aspect of the present disclosure, a method of moving material using a mower and cart is provided. The method includes the steps of providing a mower and a cart coupled a front of the mower, loading material into the cart, propelling the mower and cart, constraining movement of the cart relative to the mower about a vertical axis of rotation, rotating the cart relative to the mower about a first horizontal axis of rotation, and rotating the cart relative to the mower about a second horizontal axis of rotation that is perpendicular to the first horizontal axis of rotation. 
     Additional features of the present disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrative embodiment exemplifying the best mode of carrying out the disclosure as presently perceived. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The aforementioned aspects and many of the intended features of this disclosure will grow to be appreciated at a greater level once references to the following accompanying illustrations are expounded upon. 
         FIG. 1  is a perspective view of a zero-turn mower, hitch, and a cart system, illustrating a plurality of degrees of freedom between the cart system and the zero-turn mower provided by the hitch. 
         FIG. 2 a    is a top view of the zero-turn mower and the cart system of  FIG. 1  attached to the zero-turn mower, illustrating the degrees of freedom between the zero-turn mower and the cart system. 
         FIG. 2 b    is a side view of the zero-turn mower and the cart system of  FIG. 1  attached to the zero-turn mower, also illustrating the degrees of freedom between the zero-turn mower and the cart system. 
         FIG. 2 c    is a front view the zero-turn mower and the cart system of  FIG. 1  attached to the zero-turn mower, also illustrating the degrees of freedom between the zero-turn mower and the cart system. 
         FIG. 3  is a top view of the zero-turn mower and a portion of the cart system of  FIG. 1  showing rotation about a vertical axis. 
         FIG. 4  is a top view of a hitch of  FIG. 1  illustrating components of the hitch and connection points among the systems. 
         FIG. 5  is a side view of the zero-turn mower, the hitch, and the cart system of  FIG. 1 , illustrating components of the hitch and connection points among the systems. 
         FIG. 6  is an front view of the zero-turn mower, the hitch including a frame, and the cart system of  FIG. 1   
         FIG. 7  is a front elevation view of the hitch of  FIG. 1  including a mount crossbar, a plurality of mounting arbors, a plurality of mounting arbor clamps, a plurality of mounting rails and a plurality of mounting height clamps. 
         FIG. 8  is a top plan view of the hitch of  FIG. 1  including the mount crossbar, a plurality of end clamps, mounting arbor clamps, and mounting rails. 
     
    
    
     For the purposes of promoting an understanding of the principals of the disclosure, reference will now be made to the embodiments illustrated in the drawings, which are described below. The embodiments disclosed below are not intended to be exhaustive or limit the disclosure to the precise form disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may utilize their teachings. It will be understood that no limitation of the scope of the disclosure is thereby intended. The disclosure includes any alterations and further modifications in the illustrative devices and described methods and further applications of the principles of the disclosure which would normally occur to one skilled in the art to which the disclosure relates. 
     DETAILED DESCRIPTION OF THE DRAWINGS 
     Zero-turn mowers  12  are known in the art. As shown in  FIGS. 1-3 , mower  12  includes a plurality of front wheels  20  along with a plurality of independently controlled rear wheels  14 . Mower  12  also includes a mower seat  22  and a plurality of levers  16  that allow mower  12  to spin about a mower or vertical axis of rotation  18  between rear wheels  14 . Particular to the design, each independently controlled rear wheel  14  of mower  12  is independently controlled by an operator using dual levers  16  simultaneously, one for each rear wheel  14  respectively, to move mower  12  in the horizontal plane. By operating rear wheels  14  independently, vertical axis of rotation  18  of mower  12  can move depending on how much and in which direction handles  16  are operated. If handles  16  are operated in opposite directions so rear wheels turn at the same speed in opposite directions, vertical axis of rotation  18  will be positioned substantially between rear wheels  14  as shown in  FIG. 1 . As shown in  FIG. 3 , front wheels  20  of mower  12  are typically caster type wheels, allowing travel of wheels  20  about vertical axis  18  as mower  12  spins around vertical axis  18  between rear wheels  14  along path  72 . As shown in  FIG. 3 , front wheels  20  can travel perpendicular to vertical axis  18  as mower  12  turns and may also travel in other directions. Thus, wheels  20  can rotate relative to the ground and the mower frame/body about a horizontal axis and rotate relative to the ground and the mower frame/body about a vertical axis of rotation giving wheels two unconstrained degrees of freedom. 
     An operator controls zero-turn mower  12  from seat  22  located between levers  16 . As mentioned above, vertical axis  18  may pass through seat  22  when rear wheels  14  drive mower  12  to turn in opposite directions at the same speed. However, the location of vertical axis  18  of mower  12  is dependent on the direction and independent speed of rotation of rear wheels  14 . For example, to maneuver around an object, such as a tree, a user may use levers  16  to slow down one of rear wheels  14 , typically rear wheel  14  closest to the object, relative to other rear wheel  14  while both rear wheels  14  move in the same direction. This results in vertical axis  18  being outside of the footprint of mower  12 , often near the center of the object. As such, the turning radius and direction of turning (i.e. clockwise or counterclockwise) of mower  12  may be controlled by the direction and/or speed of rotation of rear wheels  14  as controlled by the user by levers  16 . 
     Referring again to  FIGS. 1-3 , a cart  10  and a hitch  24  are shown attached to a front  26  of mower  12 . According to the present disclosure, hitch  24  allows two degrees of rotational freedom for cart  10  relative to mower  12 . More specifically, cart  10  is able to rotate about a longitudinal axis  28  and a lateral axes  30 , but remains rotationally fixed with regards to rotation about a vertical axis  18 . Lateral axes  30  is parallel to an axis of rotation of wheels  14 . This embodiment facilitates movement of cart  10  with mower  12  even through tight turns and over uneven terrain. 
     Because of the fixed relationship of mower  12  and cart  10  about vertical axis  18 , cart  10  rotates with mower  12  about vertical axis  18  when mower  12  turns about vertical axis  18 . This fixed relationship reduces, if not eliminates, cart  10  jackknifing with mower  12  during turning of mower  12  about vertical axis  18 . 
     As shown in  FIGS. 4 and 5 , hitch  24  is attached to cart  10  by a plurality of pivot mount extensions  48 . Mounting rails  46  couple to pivot mount extensions  48  with a plurality of hitch pins  50  that go into a plurality of fastener reception holes  59  that define lateral axis  30 . Pivot mount extensions  48  allow for independent movement of mower  12  and cart  10  about lateral axis  30 , as discussed above. To remove cart  10  from mower  12 , hitch pins  50  may be removed from fastener reception holes  59 . 
     Hitch  24  further includes a crossbar  52  extending between pivot mount extensions  48  and sleeve and pin joint  54  that allows cart  10  to rotate relative to mower  12  about longitudinal axis  28 . In addition to allowing either side of cart  10  to rotate up and down about longitudinal axis  28 , sleeve and pin joint  54  allows a user to lift one side of cart  10  to dump material stored in cart  10  from the opposite side of cart  10 . 
     As shown in  FIGS. 5-6 , cart  10  includes a bin  60  being supported by a frame  56 . Further included in one embodiment, frame  56  and a plurality of caster  62  are coupled to cart  10 . Frame  56  is supported by a plurality of caster wheels  62  and is attached to a sleeve and pin joint  54  to allow movement about longitudinal axis  28  of mower  12 . 
     As indicated in  FIGS. 4-6 , cart  10  includes frame  56  coupled to sleeve and pin joint  54 , bin  60  supported by frame  56 , and caster wheels  62  that support frame  56  and can rotate freely about vertical axis  18  with frame  56 . In one embodiment, cart  10  is shown with bin  60 , but other embodiments include attachments to cart  10  such as a plug aerator, bagger, mulcher, roller, or similar attachments may be attached to mower  12 . 
     Although cart  10  and mower  12  are fixed or constrained against relative rotation about vertical axis  18 , cart  10  may move relative to mower  12  when mower  12  moves over uneven terrain. For example, if mower  12  pushes cart  10  up an incline (ex. a hill), cart  10  can rotate about lateral axis  30  independent of the angle by which mower  12  is traversing. Similarly, if mower  12  pushes cart  10  down an incline (ex. into a valley, over a crest of a hill, etc.), cart  10  can rotate in an opposite direction about lateral axis  30 . Additionally, if mower  12  pushes one side of cart  10  over an object (or along the side of a hill, etc.), cart  10  can rotate about longitudinal axis  28  so that one side of cart  10  rotates up relative to mower  12  and the opposite side of cart  10  rotates down relative to mower  12 , all things being equal. Little, if any, linear movement is provided between cart  10  and mower  12 . Thus, mower  12  and cart  10  have two degrees of rotational freedom (about axes  28 ,  30 ) between that are unconstrained and the other four potential degrees (about the vertical axis and linear movement along the three axes) of freedom are constrained or fixed. 
     Referring to  FIGS. 4-8 , hitch  24  facilitates both the fixed and unfixed rotational degrees of freedom of cart  10  and mower  12 . Hitch  24  includes a hitch crossbar  32  and a plurality of end clamps  38  attached to hitch crossbar  32 . End clamps  38  further include a mounting clamp  34 , an extension arm  39 , and a crossbar clamp  41 . Mounting clamps  34  facilitate the coupling of end clamps  38  to front  26  of mower  12  (or any other vehicle) using a fastener  58 . Hitch  24  further includes a plurality of mounting arbor clamps  40  that attach a plurality of mounting arbors  42  to hitch crossbar  32 . Hitch  24  also includes a plurality of mount height clamps  44  that are attached to a plurality of mounting rails  46  and secured by a plurality of fasteners  58 . 
     As further shown in  FIGS. 7 and 8 , mounting arbor clamps  40  attach mounting arbors  42  to crossbar hitch  32  and allow mounting arbors  42  to be adjusted horizontally along hitch crossbar  32 . Mounting arbors  42  extend vertically downwards from hitch crossbar  32 . Mount height clamps  44  attach mounting rails  46  to mounting arbors  42 . Mounting rails  46  may be adjusted vertically along mounting arbors  42 . Mount height clamps  44  secure mounting rails  46  in a number of configurations. After adjusting to a desired elevation and alignment, mounting arbors  42  and mount height clamps  44  are secured in place by fasteners  58 , such as set screws, pins, clips or other fasteners, tightened against hitch crossbar  32 . 
     Because of the above-described aspects, cart  10  may be used simultaneously with mower  12  to improve functionality of the system. Mower  12  movement forward or backward along no straight paths will cause caster wheels  62  to independently articulate to align parallel to the direction of motion of mower  12 . When mower  12  turns, using the zero-turn capabilities, casters wheels  62  and mower  12  front wheels  20  rotate independently to align perpendicular to vertical axis  18  of mower  12 . The articulating of caster wheels  62  helps insures that caster wheels  62  will roll parallel to the direction of motion of mower  12  in any combination of movements mower  12  is capable of. Caster wheels  62  also retain contact with the ground independently regardless of the lateral angle by which cart  10  articulates because sleeve and pin joint  54  pivots about longitudinal axis  28  at the same time that hitch pins  50  allow cart  10  to pivot about lateral axis  30 . 
     While this disclosure has been described as having an exemplary design, the present disclosure may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practices in the art to which this disclosure pertains.