Abstract:
A lawnmower comprising a chassis and a mower deck movable with respect to the chassis. A cylinder assembly is mounted to said chassis, and includes an actuating cylinder, and a piston shaft selectively extendable and retractable with respect to the cylinder under the influence of fluid pressure within the cylinder. A deck lift assembly is interconnected to the chassis and the mower deck for adjusting the height of the mower deck with respect to the chassis. The deck lift assembly includes a pivot member pivotally connected to the chassis. A jack is removably coupled to the pivot member, such that the chassis is raised and lowered in response to movement of the piston shaft with respect to the cylinder. The jack utilizes the existing hydraulic system and cylinder assembly of the lawnmower to raise the lawnmower with respect to the ground.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates to a jack device for power implements such as utility tractors, lawnmowers, landscaping equipment, trimmers, tillers, snow throwers, or other similar implements.  
         BACKGROUND OF THE INVENTION  
         [0002]    Power implements commonly include devices such as utility tractors, lawnmowers, landscaping equipment, trimmers, tillers, snow throwers, or other similar implements, and are used for general outdoor applications such as landscaping, gardening, lawn care, or snow removal. Lawnmowers generally include a cutting blade rotating near the ground to cut vegetation, and a mower deck or protective housing that encloses the rotational path of the cutting blade. Access to the mower deck, cutting blades or underside of the lawnmower is often required to perform regular maintenance on the lawnmower. Lawnmowers, particularly riding lawnmower and lawn tractors, are relatively heavy. A jack may be used to lift a portion of the lawnmower to provide access under the lawnmower and to the cutting blade.  
         SUMMARY OF THE INVENTION  
         [0003]    The present invention provides a lawnmower comprising a chassis and a mower deck movable with respect to the chassis. A cylinder assembly is mounted to said chassis, and includes an actuating cylinder, and a piston shaft selectively extendable and retractable with respect to the cylinder under the influence of fluid pressure within the cylinder. A deck lift assembly is interconnected to the chassis and the mower deck for adjusting the height of the mower deck with respect to the chassis. The deck lift assembly includes a pivot member pivotally connected to the chassis. A jack is removably coupled to the pivot member, such that the chassis is raised and lowered on the jack in response to movement of the piston shaft with respect to the cylinder. The mower deck is raised with respect to the chassis simultaneously as the chassis is raised with respect to a ground surface.  
           [0004]    Independent features and independent advantages of the present invention will become apparent to those skilled in the art upon review of the following detailed description and drawings.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]    [0005]FIG. 1 is a perspective view of a lawnmower embodying the present invention.  
         [0006]    [0006]FIG. 2 is an assembly view of a portion of the lawnmower of FIG. 1.  
         [0007]    [0007]FIG. 3 is an enlarged view of a portion of the lawnmower of FIG. 1.  
         [0008]    [0008]FIG. 4 is a side view of the lawnmower of FIG. 1, illustrating the lawnmower in a lowered position.  
         [0009]    [0009]FIG. 5 is a side view of the lawnmower of FIG. 1, illustrating the lawnmower in a raised position. 
     
    
       [0010]    Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.  
       DETAILED DESCRIPTION  
       [0011]    [0011]FIGS. 1 and 2 illustrate a lawnmower  10  including a chassis  14 , a seat  18  for an operator to sit in, a pair of control levers  22 , front wheels  24  and rear wheels  26  supporting the chassis  14 , a mower deck  30 , and a deck lift assembly  32 . In the illustrated embodiment, the lawnmower  10  is a belly-mount zero turn radius mower. The lawnmower  10  may also include a front mount mower. Although the illustrated lawnmower  10  is a riding lawnmower, it is possible to use a deck lift assembly on a walk-behind lawnmower or any other implement for which it is desirable to provide access to the underside of the chassis or deck, and the invention is therefore not limited to riding lawnmowers.  
         [0012]    The illustrated deck lift assembly  32  includes a cylinder assembly  33  having an hydraulic cylinder  34  with a first end  38  fixed to a post or a pair of flanges  42  that are mounted to the chassis  14 . A pair of bosses or ports  46  on the cylinder  34  receive hydraulic hoses for operation of the cylinder  34 . The cylinder assembly  33  also includes a piston shaft  50  that extends out of a second end  52  of the cylinder  34  and reciprocates in response to hydraulic fluid being pumped into or removed from the cylinder  34 . In this regard, the hydraulic cylinder  34  is preferably a double-acting cylinder.  
         [0013]    [0013]FIG. 2 illustrates other aspects of the deck lift assembly  32 . Threaded onto the end of the piston shaft  50  are a pair of jam nuts  54 . The jam nuts  54  sandwich a disk  58 . Extending from the disk  58  over the cylinder  34  is a height-of-cut strap  62 . The top surface of the cylinder  34  includes markings corresponding to the height of the lawnmower deck  30 . When viewed from above (e.g., from the position of one sitting in the seat  18 ), the end of the strap  62  aligns with the markings on the cylinder  34  and moves with the piston shaft  50  to indicate the height of the mower deck  30 .  
         [0014]    Also threaded onto the end of the piston shaft  50  is a rod end  66  having a bearing or ball joint. The deck lift assembly  32  includes a pivot member  68  having a first vertical link  70 . The pivot member  68  is pivotally coupled to the chassis  14 , and the piston shaft  50  is interconnected to the first vertical link  70  of the piston shaft  50 . A bolt, pin, or other fastener extends through the joint and fastens the joint to the top end of the first vertical link  70 . The pivot member  68  is connected to the mower lift shaft  74 , and the first vertical link  70  is supported at its lower end by a mower lift shaft  74 . The mower lift shaft  74  is supported for rotation with respect to the chassis  14  by a pair of nylon flange bushings  78 . The first vertical link  70  is keyed, welded, fastened, or otherwise fixed for rotation with the mower lift shaft  74 . The pivot member  68 , first vertical link  70 , and mower lift shaft  74  are thus pivoted about the mower lift shaft longitudinal axis in response to linear reciprocation of the piston shaft  50 .  
         [0015]    A horizontal lift assist rod  82  is pinned at a first end to the first vertical link  70  and pinned at a second end to a second vertical link  86 . The second vertical link  86  is supported by a stub shaft  90  to which it is fixed for rotation, and the stub shaft  90  is supported for rotation with respect to the chassis  14  by nylon flange bushings  94 . A pair of horizontal links  98  are fixed for rotation with the respective mower lift shaft  74  and stub shaft  90 . At least one of the horizontal links  98  is connected to the pivot member  68 . A length of chain  100  (FIG. 1) hangs from the free ends of the horizontal links  98  and is attached to the deck  30 . A similar linkage is positioned at the other side of the lawnmower  10 , and the same reference numerals are used for similar parts.  
         [0016]    Through the above-described linkage, the deck  30  is raised in response to the piston shaft  50  being extended out of the hydraulic cylinder  34 , and is lowered in response to the piston shaft being retracted into the hydraulic cylinder  34 . A plurality of cylinder stops  102  are stored on a post  104  (FIG. 1) positioned generally behind the right leg of an operator of the lawnmower  10  when the operator is seated in the seat  18 . The cylinder stops  102  may be attached to the piston shaft  50  and are sandwiched between the disk  58  and the end of the cylinder  34  to limit the extent to which the piston shaft  50  may be retracted into the cylinder  34 .  
         [0017]    [0017]FIG. 3 illustrates a portion of the lawnmower  10  including a jack  110  having a jack connector  114  and a jack shaft  118 . The jack connector  114  is pivotally coupled to the top end of the jack shaft  118 . The jack connector  114  includes two flanges  126  that are substantially parallel to one another. Each flange  126  includes an aperture that aligns with an aperture in the top end of the jack shaft  118 . A pivot pin  130  extends through the aligned apertures to pivotally couple the jack connector  114  to the jack shaft  118 . A base  134  is connected to the bottom end of the jack shaft  118 , and includes a surface area larger than the cross-sectional area of the jack shaft  118 . The base  134  contacts the ground, or other surface, to provide a sturdy foundation when the jack  110  supports the lawnmower  10 .  
         [0018]    The pivot member  68  includes a link connector  138  supported by the mower lift shaft  74  near the end of the lift shaft  74  adjacent the first vertical link  70  and the horizontal link  98 . The link connector  138  may be formed integral with the first vertical link  70  and horizontal link  98  and mounted to the mower lift shaft  74 , or may be a separate portion fastened to the first vertical link  70 , horizontal link  98 , and mower lift shaft  74 . The link connector  138 , first vertical link  70 , horizontal link  98 , and mower link shaft  74  all pivot together about the same pivot axis. Since the link connector  138  is connected to the first vertical shaft  70  and the mower lift shaft  74 , the link connector  138  is also pivoted about the mower lift shaft longitudinal axis in response to linear reciprocation of the piston shaft  50 .  
         [0019]    In FIG. 3, the link connector  138  is a hollow tubular portion having a substantially rectangular cross-section. The jack connector  114  is coupled to the link connector  138 . In the illustrated embodiment, the jack connector  114  is inserted into the link connector  138 , with the jack connector  114  including a male coupling portion, and the link connector  138  including a female coupling portion. This embodiment may be reversed, with the jack connector  114  including a female coupling portion, and the link connector  138  including a male coupling portion. Other similar coupling means may also be implemented to couple the jack connector  114  and link connector  138 .  
         [0020]    The link connector  138  includes connector apertures  142  in opposing faces of the link connector  138 . The jack connector  114  also includes a connector aperture  146  extending through the jack connector  114 . The connector apertures  142 ,  146  may be aligned, and a connector pin  150  may be inserted through the aligned connector apertures  142 ,  146  to secure the jack connector  114  to the link connector  138 . A cotter pin  154  may be used to secure the connector pin  150  within the apertures  142 ,  146 .  
         [0021]    The jack shaft  118  includes a stop portion  158  extending from its top end. The stop portion  158  is substantially T-shaped and includes a narrow middle portion  162  extending between the flanges  126 , and a wider upper portion  166  that projects outwardly beyond the width of the flanges  126 . The stop portion  158  resists the jack connector  114  from pivoting upwardly beyond the stop portion  158 .  
         [0022]    The jack connector  114  includes lock apertures  170  in the flanges  126 . When the jack connector  114  pivots upwardly far enough in relation to the jack shaft  118  to expose the lock apertures  170  from the jack shaft  118 , a lock pin  174  may be inserted through the lock apertures  170 . A cotter pin  178  may secure the lock pin within the lock apertures  170 . The lock pin  174  resists the jack connector  114  from pivoting downwardly in relation to the jack shaft  118  and lowering the lawnmower  10 . As the jack connector  114  pivots downwardly, the lock pin  174  may contact the side of the jack shaft  118  to resist the jack connector  114  from pivoting further in relation to the jack shaft  118 . The lock pin  170  may be removed to lower the lawnmower  10 .  
         [0023]    As will be explained below, the above-described arrangement of parts permits the convenient movement of the lawnmower  10  between a lowered position, in which the wheels  24 ,  26  are at ground level, and a raised position, in which at least two of the wheels  24 ,  26  are raised off the ground. FIG. 4 illustrates the lawnmower  10  in the lowered position, and FIG. 5 illustrates the lawnmower  10  in the raised position. In the illustrated embodiment, the front wheels  24  and front end of the lawnmower  10  are raised off the ground when the cylinder assembly  33  is actuated. The two rear wheels  26  remain in contact with the ground, and the lawnmower  10  is raised to pivot on the rear wheels  26 . Therefore, the chassis  14  is raised at an angle with respect to the ground overall, however, the front end of the chassis  14  is raised relatively higher than the rear portion of the chassis  14 . In other constructions, the lawnmower  10  and jack  110  may raise just the rear wheels  26 , one front wheels  24  and one rear wheel  26 , or all wheels  24 ,  26  off the ground.  
         [0024]    In operation, the lawnmower  10  is raised onto the jack  110  while the lawnmower  10  is substantially stationary in a horizontal direction. In order to raise the lawnmower  10  onto the jack.  110 , the mower deck  30  is first lowered with respect to the chassis  14  so the jack  110  may be connected to the lawnmower  10 . FIG. 4 illustrates the lawnmower  10  with the cylinder assembly  33  retracted, and the mower deck  30  lowered near the ground. The jack connector  114  is coupled to the link connector  138 , and the base  134  is positioned on the ground surface. The linear actuation of the cylinder assembly  33  is converted into rotational movement by the pivot member  68 . The pivotal movement of the pivot member  68  pivots the link connector  138  downwardly and pivots the horizontal link  98  upwardly with respect to the chassis  14 . This simultaneously raises the mower deck  30  with respect to the chassis  14 , and raises the chassis  14  (on the jack  110 ) with respect to the ground. The dual movement of the mower deck  30  and chassis  14  provides additional clearance for access under the lawnmower  10  and mower deck  30 , and to a cutting blade  182  within the mower deck  30 .  
         [0025]    [0025]FIG. 5 illustrates the lawnmower  10  in the raised position. As the piston shaft  50  extends, the lawnmower  10  may be raised onto the jack  110  until the piston shaft  50  is fully extended, an operator stops the piston shaft  50 , or until the flanges  126  of the jack connector  114  contact the stop portion  158 . The locking pin  174  may be inserted through the locking apertures  170  to secure the jack  110  and lawnmower  10  in the raised position, and resist the lowering of the lawnmower  10 . Additionally, cylinder stops  102  may be connected to the piston shaft  50 , as shown in FIG. 3, to resist the lowering of the lawnmower  10  from the jack  110 . The cylinder stops  102  are sandwiched between the disk  58  (FIG. 2) and the cylinder  34  to resist the piston shaft  50  from retracting into the cylinder  34 , thereby lowering the lawnmower  10 . When the lawnmower  10  is raised as shown in FIG. 5, the bottom portion of the lawnmower  10  and mower deck  30  may be accessed to change the cutting blade  182 , clear obstructions from the mower deck  30 , or perform other maintenance on the lawnmower  10 .  
         [0026]    The cylinder stops  102  (FIG. 3) and locking pin  174  may be removed to lower the lawnmower  10 . The piston shaft  50  retracts into the cylinder  34 , and pivots the pivot member  68  in a counter-clockwise direction, as shown in FIG. 5. As the pivot member  68  pivots, the link connector  138  and jack connector  114  also pivot with respect to the jack shaft  118  to lower the chassis  14  with respect to the ground surface. Simultaneously, the horizontal link  98  lowers the mower deck  30  with respect to the chassis  14 . When the piston shaft  50  is retracted into the cylinder  34 , the lawnmower  10  is in the lowered position and the front wheels  24  may contact the ground, as shown in FIG. 4. The jack connector  114  may then be disengaged from the link connector  138 , and the jack  110  may be removed from the lawnmower  10 .  
         [0027]    The lawnmower  10  may include a lift transport mounted to the lawnmower  10  to store the jack  110  when not in use. The lift transport may be mounted to the front of the lawnmower  10 , or onto a portion of the mower deck  30 , or any other similar location that provides adequate space to store the jack  110 . The jack  110  may be securely fastened to the lift transport.  
         [0028]    In an alternate embodiment, the lawnmower  10  may includes two jacks  110  to raise the lawnmower  10 . A second pivot member  68  may be coupled to the mower lift shaft  74  on the opposite side of the chassis  14 , and a second jack  110  could engage the second pivot member  68 . The second jack  110  would provide additional support for the lawnmower  10 .  
         [0029]    In the illustrated embodiment, the lawnmower includes a cylinder assembly  33  and a pivot member  68 . Preexisting lawnmowers having a cylinder assembly  33 , or other similar hydraulic system, may be modified to include a pivot member  68  or link connector to accommodate the jack  110 . Therefore, the jack  110  may be utilized on preexisting lawnmowers as well as new lawnmowers  10  manufactured to accommodate the jack  110 .  
         [0030]    The foregoing detailed description describes only a few of the many forms that the present invention can take, and should therefore be taken as illustrative rather than limiting. It is only the claims, including all equivalents that are intended to define the scope of the invention.