Patent Abstract:
An apparatus for lifting a deck of a vehicle, such as a lawn mower, by a foot actuated deck lift mechanism. The device includes a lift lever pivotally coupled to a frame and having a pin movably attached thereto. A lift linkage has a first end pivotally coupled to the lift lever and a second end fixedly secured on a front shaft. A connecting linkage pivotally couples the front shaft to a rear shaft. Both the front and rear shafts are rotatably coupled to the frame. The lift lever has a first end fixedly secured to the front shaft and a second free end for operation with the operator&#39;s foot. The deck is attached to the deck lift mechanism. A foot actuated deck lift mechanism, depressed by the operator&#39;s foot, and simultaneously causes the deck to rise and the lift lever to radially pivot. A pin attached to the lift lever rides atop adjustment plates. When the lift lever has pivoted a preset amount, an opening provided in the adjustment plates receives the pin. The pin then locks the deck at a height suitable for transporting the vehicle.

Full Description:
[0001]    This application claims the benefit of U.S. provisional patent application Ser. No. 60/219,520 filed Jul. 20, 2000. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    This invention relates generally to a device for lifting a mower deck suspended from a riding mower, and more specifically, to a foot actuated deck lift mechanism for lifting a mower deck automatically from a cutting position to a transport position.  
         DESCRIPTION OF THE RELATED ART  
         [0003]    There are a number of known devices for lifting a mower deck on a riding mower to a transport position. These devices typically include a hand actuated lift lever. U.S. Pat. No. 5,816,033 to Busboom et al. discloses a riding mower having an improved mower deck height control mechanism including an elongated deck height control lever pivotally movable from a lower position with respect to the frame means, to an upper position wherein, the mower deck is in its uppermost transit position. These types of deck lift arrangements require an operator to remove a hand from the drive controls or stop the mower to raise the deck to the transport position. Additionally, hand adjustment lift levers can require considerable force to raise a mower deck, particularly larger decks.  
           [0004]    In U.S. Pat. No. 5,138,825 to Trefz et al., a pedal operating lifting system is provided for replacing conventional hand operating levers. The pedal also includes a locking mechanism located on the pedal mechanism for locking the deck in the uppermost position. In U.S. Pat. No. 5,351,467 to Trefz et al, a pedal operating lifting system is provided with unlimited adjustability within a range established by the maximum and minimum deck mower heights. The &#39;825 and &#39;467 patents disclose a pedal operated deck lifting system but do not include the advantages of the system disclosed by the present invention.  
           [0005]    Accordingly, there is a need in the art for a mower deck lift mechanism that may be operated without the sole use of an operator&#39;s hands. Furthermore, there is a need for a mower deck lift assembly that may be easily attachable as an after market device addition to a riding mower, as well as a standard feature on a stock mower.  
         SUMMARY OF THE INVENTION  
         [0006]    This invention provides a foot actuated mower deck lift device to lift a mower deck from a cutting position to a transport position without the sole use of the operator&#39;s hands.  
           [0007]    More specifically, the invention is directed towards a lift mechanism that is hand and/or foot actuated for lifting a deck attached to a mower, and particularly, a mower deck attached to a riding lawn mower.  
           [0008]    The present invention discloses a system that includes the cooperation of a lift handle with a foot pedal increasing mechanical system leverage and reducing the force required by the operator to engage the system. The present invention also can be operated solely by a foot pedal and without the use of the operator&#39;s hands. Finally, the present invention includes a locking transport position positively engaged by a lift pin incorporated into the lift lever.  
           [0009]    According to the invention, the deck lift mechanism comprises a frame, a lift lever, inner and outer height adjustment plates, lift linkages, a front lift shaft, a rear lift shaft, shaft connecting linkages, and a pedal lever.  
           [0010]    In accordance with an embodiment of the invention, the lift lever is pivotally coupled to a frame and has a pin movably attached thereto. A lift linkage has a first end pivotally coupled to the lift lever and a second end fixedly secured on a front shaft. A connecting linkage pivotally couples the front shaft to a rear shaft. Both the front and rear shafts are rotatably coupled to the frame. The pedal lever has a first end fixedly secured to the front shaft and a second free end for operation with the operator&#39;s foot.  
           [0011]    In accordance with an aspect of this invention, it is desirable to provide a cutting system that permits the operator to change the cutting height while seated using an adjustment pin.  
           [0012]    In accordance with another aspect of this invention, it is further desirable to provide a cutting system wherein the operator can raise the mover deck without the use of the operator&#39;s hands to a transport position and return the deck to that exact cutting position once the transport is completed.  
           [0013]    In accordance with another aspect of this invention, it is further desirable for the lift assembly to be easily attachable as an after market device, in addition to being a standard stock feature. 
       
    
    
       [0014]    These and other aspects of this invention are illustrated in the accompanying drawings, and are more fully disclosed in the following specification.  
       DETAILED DESCRIPTION OF THE DRAWINGS  
       [0015]    [0015]FIG. 1 is an elevation view of a riding mower incorporating the deck lift mechanism in a lowered cutting position;  
         [0016]    [0016]FIG. 2 is an elevation view of a riding mower incorporating the deck lift mechanism in a transport position;  
         [0017]    [0017]FIG. 3 is an isolated exploded view of the deck lift mechanism;  
         [0018]    [0018]FIG. 4 is a perspective view of a pedal lever connected to a pedal and a deck lift lever;  
         [0019]    [0019]FIG. 5 is a front view of the pedal lever and pedal;  
         [0020]    [0020]FIG. 6 is a side view of the pedal lever of FIG. 5; and  
         [0021]    [0021]FIG. 7 is a side view of a tightening plate.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    [0022]FIGS. 1 and 2 illustrate a foot actuated deck lift mechanism  10  according to the present invention. The deck lift mechanism  10  is shown in its intended operating position, attached to a riding mower, for lifting a mower deck  12  from a cutting position to a transport position. While the remaining components of a riding lawn mower are not shown in the appended drawings, it is expected that those skilled in the art will be intimately familiar with the omitted components, all which are generally conventional.  
         [0023]    Referring now to FIG. 1, the deck lift mechanism  10  is shown in a lowered cutting position. FIG. 2 illustrates the deck lift mechanism  10  in a raised transport position. Provided in the deck lift mechanism  10  are a pair of height adjustment plates  16 ,  18  for securing the deck  12  in the transport position and for positioning the deck at a plurality of particular vertical cutting positions  58 .  
         [0024]    As shown in FIG. 3, the deck lift mechanism  10  includes a lift lever  14 , inner and outer height adjustment plates  16 ,  18 , lift linkages  20 , a front lift shaft  22 , a rear lift shaft  24 , shaft connecting linkages  26 , and a pedal lever  28 .  
         [0025]    Preferably, the deck lift mechanism  10  is actuated solely by an operator&#39;s foot using pedal lever  28  to raise the mower deck  12  to a transport position. Alternatively, the deck lift mechanism  10  may be raised to the transport position by the use of an operator&#39;s hand using lift lever  14 , or by the use of an operator&#39;s foot using pedal lever  28  assisting the hand using lift lever  14 .  
         [0026]    The lift lever  14  is carried on the frame  29  of the vehicle and has an upper end positioned for engagement with the operator&#39;s right hand and a lower end pivotally coupled with the frame  29 . The lower end provides a peg member  30  formed integral with the lift lever  14 . The peg member  30  is pivotally received by an opening formed in the vehicle frame  29 . The peg  30  defines the axis about which the lift lever  14  pivots. The upper end angles into the operator&#39;s control area  32  to provide a handle for placement of the operator&#39;s hand.  
         [0027]    As shown in FIG. 3, and illustrated by hidden lines in FIGS. 1 and 2, a spring assembly  34  is attached to the lift lever  14  between the upper and lower ends. The spring assembly  34  includes a pair of guides  36 ,  38 , a spring  40  and a lift pin  42 . The upper guide  36  is generally shaped as an inverted L with a body portion and a top portion. The body portion of the upper guide  36 , is fixedly secured to the lift lever  14  by nut and bolt assemblies  44 . The lower guide  38  is welded to the lift lever at the bottom of the upper guide  36 . The spring  40  preferably is a compression spring and is axially positioned between, and restricted by, the guides  36 ,  38 . The lift pin  42  is generally shaped as an inverted L. The upper end of the lift pin  42  is spaced at a distance from the lift lever handle  33  such that the operator&#39;s fingers can grasp the lift pin  42  while maintaining their palm on top of the handle  33 . The lower end of the lift pin  42  slidably extends through coaxially aligned openings  46 ,  48  formed in the top portion of the upper guide  46  and in the lower guide  48 , and through the inside diameter of the spring  40 . A pin  50  is received in an aperature  51  in the lift pin  42  between the lower guide  38  and the bottom of the spring  40 . The pin  50  is longer than the outside diameter of the spring  40  and, therefore, carries the spring  40  upwards when the lift pin  42  is lifted upwards thereby compressing the spring  40  between the pin  50  and the top portion of the upper guide  36 .  
         [0028]    As shown in FIG. 3, the preferred embodiment also provides a pair of height adjustment plates  16 ,  18  for securing the deck  12  in a transport position and for positioning the deck at a plurality of particular vertical cutting positions. The inner adjustment plate  16  is welded to the frame  29 . The outer adjustment plate  18  is fixedly attached to the inner adjustment plate  16  by front and rear nut, spacer and bolt assemblies  52 ,  53 . The spacers  54  maintain the adjustment plates  16 ,  18  a fixed distance apart to provide a channel  56  between the adjustment plates  16 ,  18 . Both adjustment plates  16 ,  18 , have two rows of radially spaced apart height adjustment openings  58  at fixed intervals which provide the variety of cutting positions. The openings  58  in the adjustment plates  16 ,  18  coaxially align and are positioned between the front and rear nut, spacer and bolt assemblies  52 ,  53 . The forward most opening  60  provides the lowest cutting position and each subsequent opening incrementally increases the cutting height.  
         [0029]    Referring again to FIG. 3, the lift lever  14  extends through the channel  56  formed by the adjustment plates  16 ,  18  with the peg member  30  below, and the handle  33  above the adjustment plates  16 ,  18 . The lift lever  14  radially moves along the channel  56  and is configured between the front and rear nut, spacer and bolt assemblies  52 ,  53 .  
         [0030]    As shown in FIGS. 1 and 2, the outer adjustment plate  18  is provided with an arcuate top rail  62 , uniformly distant from the peg member  30  upon which the bottom end of the lift pin  42  slides. A transport opening  64  for setting the deck into the transport position is formed by a contiguous recess, which extends through the top rail  62  into the outer adjustment plate  18 . The transport opening  64  is located rearward of the height adjustment openings  58 .  
         [0031]    The lift pin  42  is biased against the top rail  62  by the spring  40 . When the lift pin  42  is positioned over the transport opening  64 , the spring  40  urges the lift pin  42  into the transport opening  64  thereby securing the deck  12  into the transport position. Preferably, the deck  12  is raised to a six-inch cutting height when in the transport position.  
         [0032]    A height adjustment pin  66 , shown in FIG. 3, provides intermediate positioning of the deck  12 . The deck height is selected by inserting the height adjustment pin  66  through a coaxially aligned pair of height adjustment openings  58  to form a crossbeam through the channel. The lift lever  14  contacts and rests upon the height adjustment pin  66  under the force of gravity when setting the cutting height. For storage purposes and so that it does not get misplaced, the height adjustment pin  66  is attached to the outer height adjustment plate  18  by a wire, rope or chain.  
         [0033]    A pair of laterally spaced lift linkages  20  include first ends pivotally coupled with the lift lever  14 , and second ends pivotally coupled with integral connection lever  68  fixedly provided on the front lift shaft  22 .  
         [0034]    The front and rear lift shafts  22 ,  24  are rotatably coupled to the frame  29  in any known manner. The lift shafts  22 ,  24  are each provided with integral connection levers  70 . A pair of connecting linkages  26  are pivotally secured to the levers  70  on the front lift shaft  22  and the rear lift shaft  24  to form a parallel linkage, thereby pivotally coupling the front lift shaft  22  to the rear lift shaft  24 , such that rotation of the front lift shaft  22  is equally transmitted to the rear lift shaft  24 .  
         [0035]    A pair of deck lift levers  72  are integrally provided on the front and rear lift shafts  22 ,  24 . An opening  74  is provided in an outer end of each of the deck lift levers  72 . Chains  76  having an upper end attached to the openings  74  and a lower end attached to the deck  12 , support the weight of the deck  12 .  
         [0036]    Springs  78 , preferably of the tension type, include a first end attached to the levers  70  on the rear lift shaft  24  and a second end attached to the frame  29 . The springs bias the rear lift shaft  24  towards the direction of rotation in which the deck  12  is lifted. The aggregate force of the springs  78  offsets a portion of the weight of the deck  12  to assist the operator when raising the deck  12 . Additional levers and springs can be provided to increase the biasing force.  
         [0037]    As shown in FIGS. 4 and 5, the pedal lever  28  has a lower portion  80 , a middle portion  82  and an upper portion  84 . The middle portion  82  preferably angles towards the control area  32  from the lower portion  80  by forty-five degrees and the upper portion  84  preferably angles toward the control area  32  from the middle portion  82  by forty-five degrees for ergonomic operation by the operator&#39;s right foot.  
         [0038]    The lower portion  80  is removably secured to the right front deck lift lever  72 . Particularly, a tightening plate  86  cooperates with the lower portion  80  to sandwich an intermediate section of the pedal lever  28  therebetween. Preferably, two groups of three openings  88 ,  90  are provided, one group  88  in the tightening plate  86  and the other group  90  in the deck lift lever  72  as illustrated in FIGS. 4, 6 and  7 . The groups of openings  88 ,  90  coaxially align for receiving nut and bolt assemblies. Two sets of the coaxially aligned openings are positioned above, and one set of the openings below, the deck lift lever  72 . Each group of the openings  88 ,  90  are orientated as vertexes of an obtuse triangle. Each nut and bolt assembly is disposed adjacent the circumferential edge of the deck lift lever  72 , and preferably is connected thereto.  
         [0039]    As shown in FIGS. 4 and 5, a pedal  92  is fixedly secured to an inward facing edge of the upper portion  84 . The pedal  92  is formed of a unitary piece of metal and includes upper and lower inwardly facing engagement surfaces  94 ,  96 , and a top  98 , and left and right sides  100 ,  102 . The upper engagement surface  94  is rectangular. The lower engagement surface preferably is trapezoidal wherein an edge  104  of the lower surface is disposed adjacent to the middle portion  82  of the pedal lever  28 . The engagement surfaces  94 ,  96  slightly angle together to form an outwardly facing obtuse angle. The inward surface of both the upper and lower engagement surfaces  94 ,  96  can be engaged with the operator&#39;s foot for operation of the deck lift mechanism  10 . Preferably, the inward surfaces have attached an abrasive material, or high friction material such as rubber, to reduce slippage of the operator&#39;s foot. The top  98  and left and right sides  100 ,  102  perpendicularly extend outwardly form the upper engagement surface  94  to partially enclose the pedal lever upper portion  84 .  
         [0040]    The operation of the preferred embodiment will now be discussed. To place the deck  12  in the transport position, the operator places their right foot on the pedal  92  wholly retaining their hands on the drive controls and remaining seated on the vehicle seat. As the operator depresses the pedal lever  28  with their foot, the foot and rear lift shafts  22 ,  24  rotate causing the outer end of the deck lift levers  72  to radially rise upwards. The deck  12 , carried by the chains  76  attached to the deck lift levers  72 , is lifted upwards. Alternatively, the deck can be placed in the transport position by the operator moving the lift lever  14  backwards, or using a combination of the lift lever  14  and the pedal lever  28 .  
         [0041]    Simultaneously, upon engagement of the pedal lever, the rotating front lift shaft  22  transmits movement to the lift lever  14  through the pair of lift linkages  20 . As the lift lever  14  pivots the lift pin  42 , carried by the lift lever  14 , radially moves rearward sliding atop the top rail  62  towards the transport opening  64  provided in the top rail  62 . Sufficiently depressing the pedal lever  28  moves the lift lever  14 , which carries the lift pin  42  where the potential energy of the spring  40  forces the biased lift pin  42  into the transport opening  64 . The lift pin  42  sufficiently extends into the transport opening  64  so as not to be inadvertently removed or jostled therefrom, yet require minimal lifting to be removed from the transport opening  64 . When fully inserted into the transport opening  64 , the lift pin  42  extends between ⅛ and 1½ inches therein, and preferably between ¼ and ¾ inch. The lift pin  42  fits within the transport opening  64  with little lateral play. When the lift pin  42  is within the transport opening  64 , the deck  12  is in the transport position corresponding to about a six-inch cutting height.  
         [0042]    The deck can alternatively be placed in the transport position by the operator grasping the handle  33  with their right hand and pulling the lift lever  14  backwards, until the lift pin  42  reaches the transport opening. Similarly, the operator can simultaneously pull the handle  33  and depress the pedal lever  28  to place the deck into the transport position, which supports the deck at the desired cutting height.  
         [0043]    To remove the deck  12  from the transport position to a cutting position, the height adjustment pin  66  is inserted into a pair of coaxially aligned openings  58  that correspond to the desired cutting height. Then, the operator places their palm on the handle  33  with fingers extending downward grasping the lift pin  42 . The operator applies moderate pressure to the pedal  92  and/or handle  33  to offset the weight of the deck  12 , thereby, reducing the force required to remove the lift pin  42  from the transport opening  64 . The operator closes their hand forcing the lift pin  42  upwards and out of the transport opening  64 . The lift lever  14  pivotally rotates forward under the weight of the deck  12 , partially offset by the operator, until contacting the height adjustment pin  66 , and consequently setting or re-setting the cutting deck position.  
         [0044]    The cutting deck may be vertically adjusted for a plurality of cutting height settings. If the cutting deck is locked in its uppermost transport position, it may then be returned to the pre-selected cutting height set by the height adjustment pin once removed it is from the transport position.  
         [0045]    Although the invention has been shown and described with respect to certain embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon reading and understanding of the specification. The present invention includes all such equivalent alterations and modifications, and is limited only by the scope of the claims.

Technology Classification (CPC): 0