Abstract:
A cutting chamber for a mower deck blade is comprised of first and second adjoining skirt members of differing lengths to provide for a lifting air stream at the front of the chamber and a discharging air stream at the rear of the chamber. As a result, cut material can be recut in a mulching action and then easily discharged to the rear of the deck.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates generally to mower decks and more particularly to the cutting chamber surrounding the mower blade.  
         BACKGROUND OF THE INVENTION  
         [0002]    Mower decks utilized in cutting vegetation are frequently used in conditions that result in plugging and/or clogging of the cutting chamber and/or the discharge opening of the deck. Conditions which contribute to such clogging include wet, heavy and/or long grass or vegetation. To assist in lifting the vegetation to cut it in these conditions, the blades are enclosed within depending cylindrical chambers comprised of skirts or rings. These chambers contain the air stream generated by the rotating blade and assist in lifting blades of growing vegetation to cut it at the proper height.  
           [0003]    While the chambers improve the cutting of material under these conditions, clogging can still occur as the material is moved to the discharge opening, which is typically at one side of the deck. When a deck is equipped with a plurality of blades and the cut materials move across the deck to a side discharge opening, plugging can become particularly troublesome.  
           [0004]    One attempt to reduce such plugging provides for a discharge opening for each cutting blade with the opening being provided at the rear of the deck. While this design improves the discharge of material, the cutting chamber skirts surrounding the blades and the limited discharge opening still contribute to plugging.  
           [0005]    Accordingly, it would be desirable to provide a cutting deck designed to operate in wet, heavy and/or long vegetation conditions without incurring significant plugging and/or clogging.  
           [0006]    Further, it would be desirable to provide a cutting chamber that can retain the air stream generated by the blade in order to lift the blades and/or stalks of wet, heavy and/or long vegetation prior to it being cut.  
           [0007]    It would further be desirable to provide a cutting chamber and deck that permit the cut material to be effectively discharged.  
         SUMMARY OF THE INVENTION  
         [0008]    Towards these ends, there is provided a deck that includes a cutting chamber for each blade that serves to maintain the air stream necessary to lift wet, heavy and/or long blades and/or stalks of vegetation.  
           [0009]    There is further provided a substantial opening at the rear of the deck that serves as a discharge opening for material cut by the blade.  
           [0010]    To allow the cut material within the chamber to exit easily, the vertical dimension of the rear portion of the chamber adjacent to the discharge opening of the deck is less than that of the forward portion of the chamber.  
           [0011]    With the improved deck and chamber design, a mower capable of cutting and discharging wet, heavy and/or long vegetation is provided. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIG. 1 illustrates a front elevated perspective view of a front mount mower equipped with mower decks utilizing the present invention.  
         [0013]    [0013]FIG. 2 illustrates the underside of a mower deck having a plurality of cutting blades, each blade equipped with a cutting chamber constructed in accordance with the present invention.  
         [0014]    [0014]FIG. 3 illustrates a view similar to FIG. 2, but from a rear perspective and illustrating the discharge opening of the deck as well as the blade chambers.  
         [0015]    [0015]FIG. 4 illustrates a view taken along lines 4-4 of FIG. 2. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0016]    Looking first to FIG. 1, there is illustrated a vehicle in the form of a front mount mower  10  such as would be used to mow the grass and/or vegetation in parks. The vehicle  10  includes a chassis or frame  12  which is supported by steerable front wheels  14  and rear wheels  16  which are driven by an engine. An operator&#39;s platform or station  18  is carried on the frame  12  and takes the form of an enclosed cab in which there is provided an operator seat  20 , steering wheel  22  and standard equipment for maneuvering the vehicle that need not be specifically illustrated.  
         [0017]    At the front of the vehicle frame  12  are carried a pair of support arms  24  that are attached to the front and side of the frame  12 . The other ends of each support arm  24  are attached at the front of the mower deck  26 . A similar deck  28  is carried at each rear side of the vehicle  10 . Since the decks are substantially identical, only the front deck  26  will be discussed in detail.  
         [0018]    At the front of the deck  26  are carried a pair of gauge wheels  30  for supporting the forward end of the deck  26  as it moves over the ground. The gauge wheels  30  are adjustably attached to permit the height of the cut provided by the deck  26  to be adjusted.  
         [0019]    Looking now to FIGS. 2 and 3 which illustrate the underside of the deck  26  in greater detail, there will be found views of the forward underside portion and the rearward underside portion.  
         [0020]    The deck  26  includes a housing with depending top, left and right side surfaces  32 ,  34  and  36 . At the rear of the deck  26 , as best seen in FIG. 4, there is provided a discharge opening  38  that extends across the complete width of the deck  26 . The top surface  32  of the deck  26  extends horizontally and includes downwardly sloping extension  40  adjacent the rear discharge opening  38 . It is preferred to put the discharge opening  38  at the rear of the deck  26  so that discharged material is not deposited in the path of uncut grass.  
         [0021]    As illustrated, the deck  26  depicted in FIGS. 2 and 3 are equipped with three separate blades  42  which are drivingly powered in a conventional fashion that need not be shown. Each blade  42  is provided with a cutting edge  44  and a lifting edge  46 , the lifting edge  46  being provided to create the air stream that would be generated to lift the blades of grass or stalks of vegetation upwardly to allow the cutting edge  44  to sever it.  
         [0022]    Surrounding each cutting blade  42  is a chamber  48  that is comprised of downwardly extending rings or skirts attached to the top surface  32  of the deck  26 . These skirts are constructed of metal in the preferred embodiment, but could be made of plastic or composites. At the forward edge of the deck  26  and each blade  42  is provided the first downwardly extending skirt member or portion  50 . This skirt member  50  has a depth sufficient to reach the level of the cutting plane  52  of the blade  42  therein. At the rear of the deck  26 , as best illustrated in FIG. 3, is provided a second downwardly depending skirt member or portion  54  of substantially less depth, the depth being approximately ¼ of the distance between the top surface  32  of the deck  26  and the cutting plane  52  of the blade  42 . In the preferred embodiment, the first and second skirt members  50  and  54  are adjoined by a third skirt member or portion  56  to comprise the center cutting chamber  48 .  
         [0023]    It is the purpose of the first, second and third skirts  50 ,  54  and  56  to provide the cutting chamber  48  within which the blade  42  operates. The first or forward skirt member  50  functions to contain the air stream generated by the cutting blade  42  and create the vacuum to lift the grass for cutting, and then maintain the grass cuttings within the air stream for recufting to achieve a mulching effect.  
         [0024]    The rear or second skirt member  54  of the cutting chamber  48 , in the preferred embodiment being about ¼ of the distance between the top surface  32  of the deck  26  and the cutting plane  52  of the blade  42 , permits air and cut grass particles to escape from the cutting chamber  48  as it is moved toward the rear of the chamber  48  and the discharge opening  38 . Accordingly, the air as well as the cut grass being carried therein are expelled rearwardly and out the discharge opening  38  at the rear of the deck  26 .  
         [0025]    The transitional or third skirt member  56  provides for a reduction in the vacuuming or lifting effect between the front and rear skirts  50  and  54 . These transitional skirt members  56  are provided at the sides of the chamber  48  where the adjacent chambers  48  meet and air flow between them is at a minimum. In the preferred embodiment, the lower edge of the first, second and third skirt members  50 ,  54  and  56  are essentially parallel to the cutting plane  52  of the blade  42  across their full width.  
         [0026]    The second skirt member  54  preferably extends around ½ or less of the width of the cutting chamber  48 . Should it be preferred, the proportion of the chamber  48  equipped with the shortened skirt member  54  could be lessened and the proportion of the chamber  48  surrounded by the longer skirt  50  could be increased in order to increase the vacuum or lifting effect within the chamber  48 .  
         [0027]    Should additional lifting capability be desired, the front or first skirt member  50  could also be extended further around the circumference or periphery of the chamber  48 . Should a greater ability to discharge material be desired, the proportion of the circumference of the cutting chamber  48  around which the second member or smaller ring  54  extends could be expanded.  
         [0028]    In operation, the mower deck  26  is moved across the ground by a vehicle  10  such as that depicted in FIG. 1. As it moves across the ground, the blades  42  would be rotated within their respective cutting chambers  48 . The lifting portion  46  of each blade  42  would create an upwardly directed air stream or vacuum that would tend to lift the grass and/or vegetation. As the cutting edge  44  of the blade  42  then came around, it would then shear the vegetation. The cut vegetation would then move around in a circular air stream that would be contained by the first, second and third skirt members  50 ,  54  and  56 . As the cut material is moved around and around within the chamber  48 , it continues to fall and rise and be recut and recut. As it moves toward the back of the chamber  48 , the vacuum or lifting effect is reduced due to the short dimension of the second or rear skirt member  54  and therefore the air stream and cut material carried therein tends to be expelled through the discharge exit  38  at the rear of the deck  26 .  
         [0029]    In the preferred embodiment, a plurality consisting of three cutting blades are provided in the deck. Of course, a single or any preferred number of blades could be provided in the deck as might be desired.  
         [0030]    Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.