Abstract:
The conversion kit changes a conventional tracked excavator into a rubber tired excavator in just a matter of minutes. Thus, a tracked excavator can be driven down the road on pavement without the need for a transport truck and without damaging the pavement.

Description:
PRIORITY 
       [0001]    This application claims priority to U.S. Provisional Patent Application No.  61 / 032567 , filed Feb. 29, 2008, which is incorporated herein by reference in its entirety. 
     
    
     FIELD 
       [0002]    This application relates generally to modification of tracked vehicles. In particular, this application relates to converting tracked equipment to ride on tires. 
       BACKGROUND 
       [0003]    Tracked vehicles such as excavators, sometimes referred to as track-hoes, are widely used in excavation and construction. Excavators are generally tracked vehicles to provide stability and traction in a variety of working environments. For example, an excavator generally does not require outriggers required by wheeled vehicles, such as back-hoes. The wide and long track also provides greater and firmer contact with the ground than the tires of a back-hoe. In muddy or loose-soil conditions the large contact surface area of a track allows a tracked vehicle to operate in conditions where wheeled vehicles would be stuck. 
         [0004]    Tracked vehicles such as excavators have a track on each side of the vehicle. Tracked vehicles are driven by turning a drive gear attached to each of the tracks. Each track is supported by other passive gears and pulleys that rotate when the track rotates. The drive gear is driven by the engine through a transmission and causes the track to move when engaged. The drive gears on each side of the tracked vehicle are independently controlled. Tracked vehicles are turned by engaging one track and not the other, or by engaging one track in one direction and the other in the opposite direction, which results in a zero-radius turn. 
         [0005]    When tracked vehicles turn portions of the tracks slide across the ground, and may cause damage to the surface of the ground due to the weight of the vehicle and the sliding. For example, tracked vehicles may destroy or seriously damage paved surfaces when turning. Consequently, tracked vehicles are generally not driven on paved surfaces to avoid damage to those surfaces. This restriction on paved-surface travel can increase costs and time for certain jobs. For example, an excavator may be used to dig foundations and/or basements for a number of building sites in a development. When moving from one building site to another in the same development, it is often necessary to load and secure the excavator on a flatbed trailer for transport to a lot on the other side of the road or within a few hundred yards of the first site. Loading the excavator can take a significant amount of time and requires that the truck be available to transport the excavator frequently, rather than being available to move other loads and equipment. 
       SUMMARY 
       [0006]    This kit is a bolt on kit that may be specifically built for each make of excavator. The kit includes front wheels that may be steerable by attaching them to a push blade, which may be included with the excavator, depending on the make and model. For example, the Kobelco® ED150 includes a six-way hydraulically controlled blade. When wheels with tires are attached to ends of the blade, the controls used to control the blade may be used to steer the excavator when riding on the tires. 
         [0007]    The kit also includes rear wheels that may be attached to one of the sprockets or pulleys in the track drive train of the excavator. For example, the rear wheels may be attached to the rear-most track gear. A wheel adapter may be bolted to the track gear that extends out away from the outside edge of the track to allow the rear wheels to be larger than the track and suspend the excavator above the ground. A hub may be attached to the adapter to provide lugs for the rear wheels. When the tracks of the excavator are engaged, the rear wheels are turned because they are attached to the drive train of the excavator. For example, in many excavators, the two foot pedals that drive the tracks will now drive the two rubber tires mounted to the final drive. The control that operates the angle on the blade now operates the steering on the two front tires. 
         [0008]    These and other aspects of the embodiments of a tracked to wheeled vehicle conversion kit are shown and described in the following figures and related description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0009]    Various embodiments of the present invention are shown and described in reference to the numbered drawings wherein: 
           [0010]      FIG. 1  illustrates a perspective view of an excavator with an embodiment of a conversion kit attached and an exploded view of the rear wheel assembly; 
           [0011]      FIG. 2  illustrates an exploded view of a front wheel assembly attached to a push blade of an excavator; and 
           [0012]      FIG. 3  illustrates a perspective view of an excavator with an embodiment of a conversion kit attached. 
       
    
    
       [0013]    It will be appreciated that the drawings are illustrative and not limiting of the scope of embodiments of the invention, which is defined by the appended claims. The embodiments shown accomplish various aspects and objects of the invention, and are exemplary and do not and are not intended to limit the overall scope of the invention and its equivalents. It is appreciated that it is not possible to clearly show each element and aspect of the invention in a single figure, and as such, multiple figures are presented to separately illustrate the various details of the invention in greater clarity. Similarly, not every embodiment need accomplish all advantages of the present invention. 
       DETAILED DESCRIPTION  
       [0014]    The invention and accompanying drawings will now be discussed in reference to the numerals provided therein so as to enable one skilled in the art to practice the present invention. The drawings and descriptions are exemplary of various aspects of the invention and are not intended to narrow the scope of the appended claims. 
         [0015]    The figures illustrate track to wheeled vehicle conversion kit  10 . The excavator  15  illustrated is exemplary only, as embodiments of kit  10  along with aspects and features of kit  10 , may be used with various different tracked vehicles, such as bull-dozers, skid steers, etc. For the purpose of illustration and description, the figures and following description focus on the exemplary embodiments of a wheel conversion kit  10  for excavator  15 . 
         [0016]    As illustrated in  FIGS. 1 and 2 , conversion kit  10  may be attached to tracked excavator  15 , to convert the tracked vehicle into a wheeled vehicle that may be driven on paved surfaces with minimal damage to the paved surface. Conversion kit  10  may include steering wheels or front wheel assembly  140  and drive wheels or rear wheel assembly  110 . 
         [0017]    Rear wheel assembly  110  includes components to attach wheels with rubber tires  112  to track gear  42  of track  40 . Rear wheel assembly  110  may include wheel adaptor  114  and hub  118 . Wheel adaptor  114  may be attached to track gear  42 . Wheel adaptor  114  may be temporarily attached, such as by bolts, or permanently attached, such as by welding, to track gear  42 . In some embodiments, wheel adaptor  114  may be integrally formed with track gear  42  as a replacement track gear. Wheel adaptor  114  may be constructed to provide an extended connection for wheel  112  outside of the outer edge of track  40 . 
         [0018]    In some embodiments, rear wheel assembly  110  may include hub  118  with lugs  116  for attaching to wheel  112 . Hub  118  may be bolted to wheel adaptor  114 . Hub  118  may be selected to provide a bolt pattern for a desired wheel size and make. In some embodiments, hub  118  may be integrally formed with wheel adaptor  114 , or may be welded to wheel adaptor  114 . Thus, in the illustrated embodiment, wheel adaptor  114  is coupled to track gear  42  and to wheel  112  through hub  116 . When track  40  is turned using the controls and engine of excavator  15 , wheel adaptor  114  is also turned, providing power to wheel  112  to move excavator  15 . 
         [0019]    As shown in  FIGS. 1 and 2 , front wheel assembly  140  may be attached to push blade  50  of excavator  15 . Front wheel assembly  140  may include adaptor  150 , wheel  142 , and axle  146 . Push blade  50  may original equipment or previously installed optional equipment for excavator  15 . Push blade  50  may be attached to excavator  15  through attachment  60 , and may be controlled and moved with hydraulic cylinders  52 . 
         [0020]    In some embodiments, conversion kit  10  may include blade  50  and attachment  60  to couple blade  50  through attachment point  56  to excavator  15 . Attachment  60  may be coupled to the frame of excavator  15 . Hydraulic cylinders  52  may be provided at coupled to the hydraulic system of excavator  15 . Many excavators have supplemental controls, such as a thumb control on the vehicle controls, for driving auxiliary attachments on the excavator, and connection points in the hydraulic system for attaching the auxiliary attachments. These supplemental controls and auxiliary attachments may be used to control the steering of front wheel assembly  140 . 
         [0021]    Blade  50  may include mounting points  152  positioned on blade to provide connection for adaptor  150 . Mounting points  152  may be a sleeve, as illustrated, or may be a plate, or other design to allow adaptor  150  to be coupled to blade  50 . Similarly, mounting point  152  may be square, similar to a standard trailer hitch receiver, or may include an angle with bolt holes to attach adaptor  150  to blade  50 . 
         [0022]    Adaptor  150  may include axle sleeve  156  and attachment sleeve  154 . Attachment sleeve  156  may be placed in mounting points  152  and then secured to blade  50  with a pin (not shown) or other attachment devices. Adaptor  150  may provide additional forward positioning of wheels  142  to allow for a greater maneuverability of excavator  15  by extending the possible movement of blade  50  before wheels  142  contacts track  40  when turning. Axle  146  may be secured to axle sleeve  156  in a similar manner to that of attachment sleeve  156  and mounting points  152  with pins or other attachment devices, such as bolts or by welding. In some embodiments, adaptor  150  may not be necessary, or may be excluded, as axle  146  may be coupled to mounting points  152 . Axle  146  may be attached to wheel  142  using a hub and lugs. 
         [0023]    In some embodiments, kit  10  may be attached to excavator  15  by attaching wheel adaptor  114  to track gear  42  and hub  118  to wheel adaptor  114 . Adaptor  114  may be attached by removing the OEM bolts, placing the adaptor  114  directly over the final drive track gear  42 , and installing new bolts long enough to secure both adaptor  114  and the track gear  42  to excavator  15 . The bucket of excavator  15  may be used to raise one end of tracks  40 , such as a rear end near track gear  42 . Once the wheel adaptor is sufficiently raised, drive wheel  112  may be attached to hub  118  with lugs  116  for both tracks  40  and tightened. When the tracks  40  are lowered, drive wheels  112  will then contact the ground and maintain a portion of tracks  40  suspended above the ground, such that drive wheels  112  will support a portion of excavator  15 . 
         [0024]    The front end of excavator  15 , near blade  50 , may then be raised with the bucket, or blade  50  may be sufficiently raised using hydraulic controls, and wheels  142  may be attached to adaptor  150  on blade  50 . When excavator  15  is then lowered, the entire weight of excavator  15  will be borne by wheels  112  and  142 . Excavator  15  may then be driven on the wheels. To drive excavator  15  on the wheels, the tracks  40  are driven as normal, thereby driving drive wheels  112  to propel excavator  15 . Excavator  15  may be steered by manipulating cylinders  52  side-to-side, to change direction of front wheel assembly  140 . In the event excavator  15  becomes stuck in the mud or the snow, blade  50  may be raised to allow a portion of tracks  40  to contact the ground for additional traction. 
         [0025]      FIG. 3  illustrates an embodiment of excavator  15  with another embodiment of front wheel assembly  140 . In  FIG. 3 , a solid axle  160  extends between wheels  142 . Axle  160  may be coupled to blade  50  with mounting points similar to mounting points  152  described above. Axle  160  and wheels  142  may be a single, dolly-like assembly that may easily be attached to blade  50  by slipping over a portion of the blade, or with additional attachment devices, such as chains to coupled front wheel assembly  140  to blade  50 . 
         [0026]    In some embodiments, a rear tag axle may be included on excavator  15 , as a replacement for rear wheel assembly  110 . Similarly, a hydraulic dropping axle may also replace front wheel assembly  140 . Wheels  112  and wheels  142  may have tires, which can be manufactured of any material suitable for the purpose and able to carry the weight such as but not limited to solid rubber, plastic, or air filled rubber, or other tire types and designs. 
         [0027]    With kit  10  installed and with excavator riding on wheels  112 ,  142 , excavator  15  can also be used on paved roads for applications such as craning concrete barriers etc. also for snow removal within added snow plow or snow blower. The machine is simply driven by using the drive pedals that normally drive the tracks. It is steered down the road by pushing the control that angles the dozer blade. As will be appreciate by those of ordinary skill, there are many ways that kit  10  and excavator  15  could be built differently. 
         [0028]    In some embodiments, snow chains may be installed on the rubber tires; then a snow play or a snow blower can be used to remove snow on paved roads. The track excavator  15  may be driven on the road like a loader or a regular rubber tired excavator and still have all the advantages of a track excavator once at a jobsite. Tracks  40  may be taken completely off if rubber tires are needed for an extended period of time, or to repair the tracks. Otherwise tracks  40  just turn in the air as excavator  15  is driven down the road on rubber tires of wheels  112 ,  142 . 
         [0029]    It will be appreciated that numerous changes may be made to the present invention without departing from the scope of the claims.