Abstract:
A mower apparatus and method for making the same is provided. A mower apparatus may include a multi-wheel drive mower system having at least one mower blade and at least one front wheel positioned proximate the front of the mower system and at least one rear wheel positioned proximate the rear of the mower system. The mower apparatus may also include a zero turn assembly haying at least one caster wheel. The zero turn assembly may be rotatably attached to the multi-wheel drive mower system to provide the mower apparatus with the capability of operating in either a multi-wheel drive mode having at least the at least one front wheel and the at least one rear wheel engaging the ground or a zero turn radius mode having only the at least one caster wheel and the at least one rear wheel engaging the ground.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of and incorporates by reference herein the disclosure of U.S. Ser. No. 61/287,240, filed Dec. 17, 2009. 
     
    
     BACKGROUND 
       [0002]    Zero turn radius lawn mowers are common in the lawn mowing industry and are generally regarded as the standard when it comes to maneuverability. One drawback with the zero turn radius lawn mower is its reduced ability to hold a hillside when mowing. The reason for this short coming is that such zero turn radius mowers have just two drive wheels located at the rear of the machine and two front wheels set on casters. Because the caster wheels spin freely and don&#39;t have their own power, the zero turn radius mowers tend to “steer” down a slope and have some difficulty negotiating steep and/or wet terrain. When an operator of a zero turn radius mower attempts to negotiate steep and/or wet terrain, the rear drive wheels may tear through the turf as they spin in place. Homeowners and commercial grass cutters have been forced to trim such areas with other cutting equipment thus decreasing their efficiency in performing their job. 
         [0003]    Accordingly, there exists a need for a system that can allow mower operators to mow with great maneuverability and safely on uneven and/or wet terrain. 
       SUMMARY 
       [0004]    The present disclosure discloses a mower apparatus and method for making the same. One embodiment of a mower apparatus includes a multi-wheel drive mower system having at least one mower blade and at least one front wheel positioned proximate the front of the mower system and at least one rear wheel positioned proximate the rear of the mower system. The mower apparatus also includes a zero turn assembly having at least one caster wheel. The zero turn assembly is rotatably attached to the multi-wheel drive mower system to provide the mower apparatus with the capability of operating in either a multi-wheel drive mode having at least the at least one front wheel and the at least one rear wheel engaging the ground or a zero turn radius mode having only the at least one caster wheel and the at least one rear wheel engaging the ground. 
         [0005]    One embodiment of a mower includes at least one mower blade, drive wheels and an engine. The mower also includes at least one front wheel positioned relatively closer to a front end of the mower than the drive wheels and at least one zero-turn wheel positioned relatively closer to the front of the mower than the drive wheels. The mower is adjustable between a first position in which the at least one front wheel engages the ground and the at least one zero-turn wheel is disengaged from the ground, and a second position in which the at least one zero-turn wheel engages the ground and the at least one front wheel is disengaged from the ground. 
         [0006]    One embodiment of a method of assembling a mower apparatus includes providing a four wheel drive mower system having at least one mower blade and a first pair of wheels positioned near the front of the mower system and a second pair of wheels positioned near the rear of the mower system and a zero turn assembly having a plurality of caster wheels. The method of assembling also includes attaching the zero turn assembly to the four wheel drive mower system such that the zero turn assembly is capable of rotating relative to the four wheel drive mower system to provide the mower apparatus with the capability of operating in either a four wheel drive mode having at least the first and second pair of wheels engaging the ground or a zero turn radius mode having only the plurality of caster wheels and second pair of wheels engaging the ground. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The features and advantages of this disclosure, and the manner of attaining them, will be more apparent and better understood by reference to the following descriptions of the disclosed method and computer-readable program, taken in conjunction with the accompanying drawings, wherein: 
           [0008]      FIG. 1  shows a mower apparatus according to at least one embodiment of the present disclosure. 
           [0009]      FIG. 2  shows a frame and transmission frame assembly attached together according to at least one embodiment the present disclosure. 
           [0010]      FIG. 3  shows an exploded view of a steering mechanism and transmission frame assembly according to at least one embodiment of the present disclosure. 
           [0011]      FIG. 4  shows a top view of the zero turn assembly shown in  FIG. 1 . 
           [0012]      FIG. 5  shows a perspective view of the zero turn assembly shown in  FIG. 1 . 
           [0013]      FIG. 6  shows the mower apparatus shown in  FIG. 1  in zero turn radius mode. 
           [0014]      FIG. 7  shows the mower apparatus shown in  FIG. 1  in four wheel drive mode. 
           [0015]      FIG. 8  shows the mower apparatus shown in  FIG. 1  shows the deck changing in height as the zero turn assembly converts the apparatus from a four wheel drive mode to a zero turn mode. 
           [0016]      FIG. 9  shows various deck components assembled according to at least one embodiment of the present disclosure. 
           [0017]      FIG. 10  shows an oil accumulator attached to the engine of a mower apparatus according to at least one embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be directed to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It should be noted that no limitation of the scope of this disclosure is thereby intended. 
         [0019]    The present disclosure provides a mower apparatus and a method for manufacture of the same.  FIG. 1  shows a perspective view of a mower apparatus  1000  according to one embodiment of the present disclosure. As shown in  FIG. 1 , mower apparatus  1000  includes right and left steering levers or handles  1206 ,  1208  for maneuvering the mower apparatus  1000 , a seat  1850 , a deck portion  1300  including one or more blades  1305  (not shown), front right wheel  1605  and front left wheel  1615 , rear right wheel  1610  (shown in  FIG. 10 ) and rear left wheel  1620 , a zero turn assembly  1700  including caster wheels  1720 ,  1730 , and an engine  1400  for providing power to the mower apparatus  1000  and performing such functions as operating the blades  1305 , front right wheel  1605  and front left wheel  1615 , rear right wheel  1610  and rear left wheel  1620  and operating the zero turn assembly  1700  to provide the mower apparatus  1000  with the ability to alternate between four wheel drive and zero turn radius movement. 
         [0020]      FIG. 2  shows a frame  1100  and a transmission frame assembly  1800  that may be included in the mower apparatus  1000 . The frame  1100  and transmission frame assembly  1800  may be used for connecting and supporting various components of the mower apparatus  1000 . For example, the deck portion  1300 , engine  1400 , and zero turn assembly  1700  may all be connected to the frame  1100 . The front and rear wheels  1605 , 1615 , 1610 , 1620  may also be connected and supported by the frame  1100 . The frame  1100  may be various shapes including, but not limited to, an H-shape, an I-shape, rectangular-shape, and square shape. The frame  1100  may be various sizes. It should be noted that the size of the engine  1400  typically influences the size of the frame  1100 . The frame  1100  may be formed of tubular or solid bars of steel; however other metals and configurations may be used. 
         [0021]    The transmission frame assembly  1800  may serve as a means for mounting components of the mower apparatus  1000  to the mower frame  1100 . Such components may include, but are not limited to, a steering mechanism  1200  (described below), T gear box, left steering pump, right steering pump, and seat  1850  and corresponding seat pan. The transmission frame assembly  1800  may include vertical and horizontal metal (e.g., steel) bars or tubing that are located beneath the seat  1850  and corresponding seat pan. The transmission frame assembly  1800  may be connected to the frame  1100  by various means, such as, for example, four bolts (as illustratively shown in  FIG. 2 ) or using welds. The transmission frame assembly  1800  may be various shapes, including, but not limited to, rectangle, square, or tubular in shape. The transmission frame assembly  1800  may be formed of various materials, including, but not limited to, steel, aluminum, and composites. 
         [0022]    As shown in  FIG. 3 , right and left steering handles  1206 ,  1208  are components of the steering lever mechanism  1200 . The steering lever mechanism  1200  may be attached to the transmission frame assembly  1800  in various ways, including, but not limited to, bolts and welds. The steering lever mechanism  1200 , and consequently the mower apparatus  1000 , can be manipulated by moving handles  1206 ,  1208  forward and backward. For example, by moving the levers  1206 ,  1208  forward in tandem, the mower apparatus  1000  may move forward. By moving the levers  1206 ,  1208  backward in tandem, the mower apparatus  1000  may move backward. Either lever may be moved forward or backward independently to effectuate a turn. Illustratively, the degree at which each lever is independently moved will directly impact the speed at which the associated wheel is driven, and hence the speed at which the mower apparatus  1000  turns. 
         [0023]    The operation of the steering lever mechanism  1200  in the mower apparatus  1000  may be accomplished in a variety of ways. In one example, both steering levers  1206 ,  1208  may be connected to a steering block. Upon manipulation by an operator of the mower apparatus  1000  using the levers  1206 ,  1208 , the steering block manipulates (via a mechanical means) a linkage rod that is attached to a hydraulic pump arm. Depending on the position of the steering levers  1206 ,  1208 , the hydraulic pump arm moves forward or backward. The movement of the hydraulic pump arm causes hydraulic fluid to move to a wheel motor via hydraulic lines. As a result, the wheel motor activates the respective drive wheels  1605 ,  1610 ,  1615 ,  1620  as seen in  FIG. 1 . 
         [0024]    The wheels  1605 ,  1610 ,  1615 ,  1620  of the mower apparatus  1000  may be formed of any type of material and may vary in size. For example, one or more of the wheels  1605 ,  1610 ,  1615 ,  1620  may be formed of rubber or plastic and having the following dimensions: 27 inches high×13 inches wide×12 inches inside tire diameter. In the illustrated embodiments, the front wheels  1605 ,  1615  and rear wheels  1610 ,  1620  are powered; however, it is within the scope of this disclosure for the front wheels  1605 , 1615  to be temporarily or permanently unpowered but fixed or partially fixed to prevent undesired turning movement of the wheels. Also, in the illustrated embodiments, the mower apparatus  1000  includes two front wheels  1605 ,  1615  and two rear wheels  1610 ,  1620 ; however, it is within the scope of this disclosure for there to be only one or more than two front wheels or only one or more than two rear wheels. 
         [0025]    As mentioned above and shown in  FIG. 1 , mower apparatus  1000  includes a zero turn assembly (or ZTA)  1700 . The ZTA  1700  provides the mower apparatus  1000  with the capability of being operated in either zero turn radius style mowing or multi-wheel drive mowing. As shown in  FIGS. 1 ,  4 , and  5 , the ZTA  1700  includes two caster wheels  1720 ,  1730  and a hydraulic actuator cylinder  1710 . In  FIGS. 1 ,  4 , and  5 , the ZTA  1700  also includes a framework  1715  that connects the caster wheels  1720 ,  1730  to the frame  1100  or other portion of the mower apparatus  1000  such that the ZTA  1700  is able to rotate relative to the other components of the mower apparatus  1000  (e.g., frame  1100 ). As shown in  FIG. 4 , the ZTA  1700  may be attached to the frame  1100  using two hinges  1705 ,  1707 . The hydraulic actuator cylinder  1710  itself may be attached to the frame using a bolt and a clevis pin. In  FIG. 4 , the ZTA  1700  is able to rotate about the hinges  1705 ,  1707  and, therefore, about the frame  1100 . While  FIG. 4  shows the use of a hydraulic actuator cylinder  1710 , it should be noted that the ZTA  1700  may be rotated relative to the other components of the mower apparatus  1000  using various other mechanisms. 
         [0026]      FIG. 6  shows the mower apparatus  1000  in the zero turn radius configuration. As shown in  FIG. 6 , the ZTA  1700  has been actuated such that the caster wheels  1720 ,  1730  come into contact with the ground, resulting in the two front wheels  1605 ,  1615  of the mower apparatus  1000  suspended above the ground. When the two front wheels  1605 ,  1615  are suspended above the ground, the mower apparatus  1000  is capable of operating like a zero turn radius mower. As shown in  FIG. 7 , the ZTA  1700  may be actuated such that the two caster wheels  1720 ,  1730  are suspended above the ground, resulting in the two front wheels  1605 ,  1615  being in contact with the ground. When the two front wheels  1605  and  1615  are in contact with the ground, the mower apparatus  1000  is capable of operating in four wheel drive. 
         [0027]    In order to adjust the mower apparatus  1000  such that it can operate in either zero turn radius or four wheel drive mode, the operator may manipulate an electric switch  1210  (shown in  FIG. 1 ) which sends an electric signal to a solenoid operated valve. By pressing the switch  1210 , the operator manipulates the solenoid operated valve which in turn causes hydraulic fluid to be funneled to the hydraulic actuator cylinder  1710  through a two-way check valve  2400 . As shown in  FIG. 4 , there are two hydraulic lines that run from the check valve  2400  to the hydraulic cylinder  1710 . Depending on how the hydraulic actuator cylinder  1710  is actuated, the ZTA  1700  rotates either upwards or downwards. 
         [0028]    While the mower apparatus  1000  is illustratively depicted as having an electric switch  1210 , it should be noted that any type or kind of switching may be used. For example, the switching may be carried out manually, electronically, or hydraulically. In addition, it should be noted that the hydraulic piston described herein may be replaced or complemented with any other kind of actuator that allows the ZTA  1700  to move or rotate relative to the frame  1100  or other portion of the mower apparatus  1000 . 
         [0029]    As shown in  FIG. 1 , the electronic switch  1210  may be located on either steering handle  1206 ,  1208 . Of course, the electronic switch  1210  may be located in other places and on other components. While the two-way check valve  2400  is attached to the frame  1100  adjacent to the front left wheel  1615 , it may be located anywhere on the frame  1100  or other component. It should be noted that the framework  1715  of ZIA  1700  may be various shapes and sizes and formed of various materials. For example, in  FIG. 4 , the framework  1715  resembles the shape of a trapezoid. Alternatively, the framework  1715  may be another shape, such as, for example, a rectangle or a square. The framework  1715  may be formed of various materials, including, but not limited to, metal and composites. 
         [0030]    The caster wheels  1720 ,  1730  of the ZTA  1700  may be formed of any type of material and may vary in size. For example, one or more of the wheels  1720 ,  1730  may be formed of rubber or plastic. While caster wheels  1720 ,  1730  are illustratively depicted as such that they can spin freely, it is within the scope of this disclosure for one or more caster wheels to be coupled to be steerable or otherwise moveable to accommodate a generally highly steerable or near zero-turn capability. In other words, it is within the scope of this disclosure for the caster wheels  1720 ,  1730  to be temporarily or permanently powered and/or temporarily or permanently steerable. Also, in the illustrated embodiments, the ZTA  1700  includes two caster wheels  1720 ,  1730 ; however, it is within the scope of this disclosure for there to be only one or more than two caster wheels. 
         [0031]    The deck  1300  of the mower apparatus  1000  houses the blades  1310 , which may be spun with the aid of a belt that is attached to the engine  1400  to cut grass and the like. It should be noted that the blades  1310  may be attached to a spindle underneath the deck  1300 . According to one embodiment of the present disclosure and as exemplified in  FIG. 8 , the deck  1300  of the mower apparatus  1000  includes a deck leveling system that can change the height of the deck  1300  relative to the frame  1100  by manual operation or based on the orientation of the ZTA  1700 . In this way, the mower apparatus  1000  may compensate for the change in height between the ground and the blades  1310  that occurs when the mower system  1000  shifts between a four wheel drive configuration to a zero turn radius configuration. As a result, the mower apparatus  1000  can continuously mow at a consistent height regardless of the terrain being negotiated. 
         [0032]    In  FIG. 1 , the deck  1300  is located beneath the frame  1100  itself. The deck  1300  may be connected to the frame  1100  using a variety of components. In one example, as shown in  FIG. 9 , the deck  1300  may be hung from the frame  1100  via four chains, where long chain  1351  is wrapped over sprockets  1352 ,  1353  and long chain  1354  is wrapped over sprockets  1355 , 1356 , It should be noted that long chains  1351 ,  1354  may be permanently attached to sprockets  1353 ,  1356  via master links towards the front of the mower apparatus  1000 . As shown in  FIG. 9 , sprockets  1353 ,  1356  may be welded to the deck lift cross shaft  1357 , which may be held in place beneath the frame  1100  via six steel saddles that are welded to the bottom of frame  1100 . The rear sprocket rotating bolt  1358 ,  1359  may be attached to the frame  1100  via two steel saddles that are welded to the bottom of frame  1100 . As shown in  FIG. 9 , the rear sprocket rotating bolts  1358 ,  1359  may have sprockets  1352 ,  1355 , respectively, attached to said rotating bolts  1358 ,  1359 . The tension on chains  1351 ,  1354  may keep sprockets  1552 ,  1355  properly aligned laterally along their respective rear sprocket rotating bolts. 
         [0033]    The right and left front short chain sprockets  1360 ,  1361  may be attached to deck lift cross shaft  1357  via welds but may be attached by other means, such as, for example, bolts. The front short chain sprockets  1360 ,  1361  may have short chains  1370 ,  1372  wrapped around them that are permanently connected to the sprockets  1360 ,  1361  themselves via a master link in the chain. The short chains  1370 ,  1372  may also be connected to respective deck leveling studs  1362 ,  1363  via master links in the chains. The deck leveling studs  1362 ,  1363  may pass through holes in the mower deck  1300  and may be fastened in place via a nut. In  FIG. 9 , there are two deck leveling studs  1364 ,  1365  that attach to the long chains  1351 ,  1354  respectively in the same manner as described above. The two deck leveling studs  1364 ,  1365  may be further attached to the rear of the deck in substantially the same manner as described above. 
         [0034]    As shown in  FIG. 9 , the electric deck lift sprocket  1366  is attached to the right side of the deck lift cross shaft  1357 . The electric deck lift sprocket  1366  may be welded to the deck lift cross shaft  1357  or attached in some other fashion, such as, for example, using fasteners. As shown in  FIG. 9 , the electric deck lift chain  1367  is wrapped around and secured to the sprocket  1366  via a master link. In  FIG. 9 , the electric deck lift chain  1367  is attached to a steel flat bar  1368  via a master link. As shown in  FIG. 9 , the steel flat bar  1368  may be connected to the electric actuator  1369  via a bolt and nut. The electric actuator  1369  may be controlled by the operator so as to lift and lower the mower deck  1300  at will or controlled automatically in response to the adjustment between zero turn and four wheel drive configurations. The operator may operate the electric actuator  1369  in various ways, such as, for example, using a toggle switch located on the instrument control panel. 
         [0035]    In  FIG. 1 , the mower apparatus  1000  also includes an engine  1400  that provides power to the entire mower apparatus. The engine  1400  is connected to various systems via belts so as to turn the blades  1310 , turn pulleys that are connected to the T gear box, and operate various components. As generally describe above, the rotation of the T gear box results in hydraulic fluid being sent to hydraulic pumps and then to the wheel motors. The engine  1400  may also be connected directly to the hydraulic pumps, thereby eliminating the need for a T gear box. The engine  1400  may be affixed to the frame  1100  in various ways, such as, for example, four bolts. The engine may be propelled by gasoline, natural gas, diesel, propane or other fuels. 
         [0036]    As shown in  FIG. 1 , the mower apparatus  1000  includes a seat  1850 . The seat  1850  may be supported by the frame  1100  and bolted to a seat pan, which is bolted to the transmission frame assembly  1800 . Gasoline and diesel powered mower apparatus  1000  machines may include fuel tanks attached to fender assemblies, which may be coupled to the lateral sides of the transmission frame assembly  1800 . For a mower apparatus  1000  powered by fuels other than gasoline, the fuel tanks may be attached directly to the transmission frame assembly  1800 . It should be noted that in some instances a mower apparatus  1000  may not include a seat  1850 . For example, the mower apparatus  1000  may be designed for an operator to stand while operating the apparatus  1000 . 
         [0037]    As shown in  FIG. 10 , the mower apparatus  1000  may optionally include an oil accumulator  3500  to aid in operating the apparatus  1000  on steeper grades. In  FIG. 10 , the oil accumulator  3500  is attached to the engine  1400 . When the engine  1400  is started and oil pressure increases, oil pressure overcomes the spring force exerted by a spring within the accumulator  3500 , causing oil to be introduced in the accumulator  3500  and displacing an internal piston of the accumulator  3500 , During operation of the mower apparatus  1000 , the oil accumulator  3500  essentially functions to send engine oil to the engine  1400  for continual lubrication despite the terrain the mower apparatus  1000  is traversing. As the mower apparatus  1000  ascends or descends a steep grade, gravity pulls the engine oil away from the oil pump thus reducing lubrication and placing the engine  1400  at risk of lack of lubrication. The oil accumulator  3500  forces engine oil back to the oil pump so that it can be picked up by the oil pump and circulated to lubricate the engine  1400 . When the engine  1400  is stopped and oil pressure reduces, the spring tension causes the piston to force oil from the accumulator  3500  to the oil sump of the engine  1400 . In one example, additional oil is added to the engine  1400  and or other components of the mower apparatus  1000  to assure adequate oil will be present in the oil sump and the accumulator  3500  to compensate when operating on a grade. 
         [0038]    While various embodiments of a mower apparatus and method for manufacturing the same have been described in considerable detail herein, the embodiments are merely offered by way of non-limiting examples of the disclosure described herein. It will therefore be understood that various changes and modifications may be made, and equivalents may be substituted for elements thereof, without departing from the scope of the disclosure. For example, any number of components referenced herein may have one or more features/configurations of another component referenced within the present disclosure. Indeed, this disclosure is not intended to be exhaustive or to limit the scope of the disclosure. 
         [0039]    Further, in describing representative embodiments, the disclosure may have presented a method and/or process as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. Other sequences of steps may be possible. Therefore, the particular order of the steps disclosed herein should not be construed as limitations of the present disclosure. In addition, disclosure directed to a method and/or process should not be limited to the performance of their steps in the order written. Such sequences may be varied and still remain within the scope of the present disclosure.