Abstract:
A method and apparatus for a resilient and flexible discharge deflecting chute of a lawn mower. A discharge deflecting chute utilizing a flexible sheet shaped into a chute-like form by a frame is disclosed. A flexible, resilient discharge deflecting chute is provided which has memory characteristics and returns to shape even after substantial deflection from obstacle contact. Preferably, a flexible, resilient material selected for this discharge deflecting chute has sufficient stiffness to substantially maintain its shape in normal operation. The flexible, resilient material selected for this discharge deflecting chute has sufficient flexibility to deflect substantially when contacted by obstructions during mowing operations.

Description:
RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of U.S. Ser. No. 10/444,663, filed May 22, 2003, and incorporated herein by reference. 
     
    
     TECHNICAL FIELD  
       [0002]     This invention generally relates to a cutting unit for a turf mower. More particularly, the invention relates to a deflector assembly in selective communication with turf clippings dispersed from the cutting unit of a turf mower.  
       BACKGROUND OF THE INVENTION  
       [0003]     Turf cutting equipment, such as rotary mowers, have a cutting deck carrying one or more turf cutting implements within a cutting chamber. Open access to the cutting chamber may be provided to allow for wide dispersal of grass clippings. Side discharge mowers have an access provided at a laterally disposed side of the cutting deck and are often equipped with a discharge deflecting chute to keep debris thrown from the mower blade at a very low altitude. Known discharge deflecting chute may be formed from metal or plastic parts. These discharge chutes are generally rigid and may be damaged during use from contact with obstacles. Additionally, debris may be deflected off the interior surfaces of the chute and thrown away from the mower at an undesirable trajectory.  
         [0004]     A common problem associated with some typical discharge deflecting chutes is that they interfere with convenient operation of the mower. Common discharge deflecting chutes are often damaged during use due to contact with obstacles. Additionally, these discharge chutes can inflict damage to trees, signposts, and other structures during contact. Areas of turf unevenness may additionally be damaged by the rigid discharge deflecting chutes contacting and scraping the turf to reveal bare soil.  
         [0005]     It is desirable to provide a mower deck which includes a side discharge chute that directs clippings during operation in the side discharge mode. It would also be desirable for such a mower to provide or hinder the chute from becoming permanently bent, deformed or warped when the discharge chute contacts obstacles. It would also be desirable for such a mower to provide or hinder the chute from causing damage to items the chute may come into contact with during operation or transport of the mower.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention is directed to a resilient and flexible discharge deflecting chute. One embodiment of the present invention utilizes a reinforced sheet rubber form which is shaped into a chute shape by a frame. In a preferred embodiment, a flexible, resilient discharge deflecting chute is provided which has memory characteristics and returns to shape even after substantial deflection from obstacle contact. The flexible, resilient material selected for this discharge deflecting chute has sufficient stiffness to substantially maintain its shape in normal operation. The flexible, resilient material selected for this discharge deflecting chute has sufficient flexibility to deflect substantially when contacted by obstructions. The flexible, resilient material selected for this discharge deflecting chute has sufficient resiliency to substantially return to its normal shape after contact and deformation by an obstacle.  
         [0007]     Additional embodiments of the present invention include variations in construction and materials selection. The present invention may be produced as an injection molded resilient and flexible material of equivalent flexural and resiliency characteristics. Furthermore, the frame utilized to control the shape of a rubber sheet may be substantially reproduced in alternate form to provide the same function. The present invention may be produced as an injection molded resilient material of equivalent flexural and resiliency characteristics, with integral rigid plastic or steel portions to control the shape and mounting structure of the discharge deflecting chute.  
         [0008]     Another benefit of the present deflecting chute is that the resilient and flexible material may absorb a greater amount of the kinetic energy of thrown debris as compared to known generally rigid metal or plastic deflecting chutes. A variety of flexible and resilient sheet materials may be utilized to form the discharge chute of the present invention. In a preferred embodiment, the discharge deflecting chute comprises a fiber-reinforced rubber sheet.  
         [0009]     One object of the present invention is to provide an improved grass deflector attachment for a rotary lawn mower which is durable and which is inexpensive and easily manufactured.  
         [0010]     A method of providing a discharge chute is also disclosed to include the steps of providing a sheet element and deforming the sheet element into a chute-like shape with a frame. The frame preferably may include a U-shaped plate or separate brackets which engage the sheet element to generate a chute-like form. In one embodiment, a pair of plates are provided which engage the sheet element in a clamping manner. Alternative embodiments may include more than two plates or elements which engage the sheet element to form the chute shape.  
         [0011]     In accordance with these objects and other advantages which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     This invention will be described hereafter in the Detailed Description, taken in conjunction with the following drawings, in which like reference numerals refer to like elements or parts throughout.  
         [0013]      FIG. 1  is a perspective view of a mower incorporating to the invention;  
         [0014]      FIG. 2  is a perspective view of a rotary cutting unit on the mower of  FIG. 1 ;  
         [0015]      FIG. 3  is a perspective view of the components of a discharge deflecting chute of  FIGS. 1 and 2 .  
         [0016]      FIG. 4  is a perspective view of components of another embodiment of a discharge deflecting chute of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0017]     The mower of this invention is referred to generally by the reference numeral  10  and is seen to be a riding lawn mower in the drawings. Although the invention described herein is ideally suited for use with a riding mower, it is believed that the invention described herein also has applicability with respect to walk-behind mowers. Mower  10  includes a frame  12  having a pair of drive wheels  14  positioned on opposite sides of the frame means  12  at the rearward end of the mower. An internal combustion engine  20  is mounted on frame  12 . Engine  20  is operatively connected to a pair of hydraulic pumps which are operatively connected to hydraulic motors operatively connected to the drive wheels  14 , respectively. Mower  10  also includes an operator&#39;s station  27  and steering controls  27 ′.  
         [0018]     Mower  10  includes a mower deck  28  at the forward end thereof which includes a top wall  30 , front wall  32 , rear wall  34 , and opposite side walls  36  and  38 . Caster wheel assemblies  39  support the forward end of deck  28 . A stabilizer rod assembly connects the rearward end of the mower deck  28  to the frame means  12  in conventional fashion. Mower deck  28  is supported by a plurality of chain members  42  which are connected to a mower deck height control mechanism generally referred to by the reference numeral  44  to enable the mower deck to be raised or lowered with respect to the frame means  12 .  
         [0019]     A rotary cutting unit is shown installed on a mower  10 . Cutting deck  28  includes a downwardly facing cutting chamber which is defined by walls  32 ,  34 ,  36 , and  38  that extends downwardly from top wall  30 . As is well known in rotary cutting decks, this wall arrangement provides a generally enclosed cutting chamber which is enclosed over the sides and top thereof but is open at the bottom thereof. Rotary cutting blades are carried inside this cutting chamber and rotate in a generally horizontal cutting plane about a generally vertical rotational axis. Each rotary cutting blade has sharpened cutting edges which cut the grass as blade rotates in its cutting plane. The height of cut is determined by how far the blades are positioned above the ground which is, in turn, determined by the relative position of cutting deck on roller frame. A means for rotating the cutting blade within cutting chamber is provided on cutting deck  28 . This rotating means may comprise a pulley system. Alternatively, an individual electric or hydraulic motor may be utilized to power the cutting blades. Shroud wall  36  is provided with a grass discharge opening to allow grass clippings to exit through shroud wall  36  in some desired direction, i.e. to the side of cutting deck as shown in  FIG. 1  or to the rear of cutting deck  28 .  
         [0020]     Referring now to  FIGS. 2 and 3 , a discharge deflector assembly is indicated as numeral  50 . Discharge assembly  50  includes a sheet  52  and a frame assembly  54  for deforming sheet  52  into a chute shape and for connecting sheet  52  to the cutting deck  28 . Discharge assembly  50  is movably connected to mower deck  28  via a hinge connection  56  which permits the discharge assembly  50  to assume a guarded position as indicated in  FIG. 2 , and an unguarded position (not shown) where the discharge assembly  50  has pivoted away from the ground surface about a pivot axis. When in the guard position, discharge assembly  50  is generally aligned with side discharge opening so that clippings are directed through an interior region of discharge assembly  50 .  
         [0021]     Discharge assembly  50  includes chute having a top surface  60  and a pair of side surfaces  62 ,  64 . Top surface  60  is directed downwardly at an angle of approximately 5 degrees. Side surface  62  (which is in front of side surface  64  during operation) is generally perpendicular to top surface  60 , while side surface  64  is provided at a backwardly directed angle relative to top surface  60  to facilitate dispersal of clippings. This angle, which is greater than 90 degrees, is indicated as “α” in  FIG. 3 . Side surface  62  has a lower edge  66  which is substantially closer to the turf surface than a corresponding lower edge of side surface  64 . The chute can assume a variety of different shapes. For example, the chute may have a top surface  60  and only a front side surface  62 . The chute may be configured as a portion of a cylinder, etc.  
         [0022]     Sheet  52  is supported by frame assembly  54  on one end and is unsupported at a free end  72 . Structural integrity is enhanced by formation of side surfaces  62 ,  64 . Sheet  52  may be manufactured by a cutting a form out of a larger sheet of rubber material. Sheet  52  may be manufactured from a wide variety of natural and/or synthetic elastomeric products. A preferred material for sheet  52  is a rubber sheet having a thickness of approximately 0.3 inch, and being manufactured by Goodyear Manufacturing, Inc. Sheet  52  preferably has a width, W, of between 4 and 16 inches. Sheet  52  may have a total surface area of between 100 to 500 square inches. In a preferred embodiment, sheet  52  has a surface area of approximately 350 square inches. Sheet  52  may be selected from a variety of known resilient materials. Reinforced or laminated sheeting may be selected. The chute may contain stiffener elements, such as wires or thickened regions of rubber. The chute may be a molded, preformed component. For example, the chute may include an injection molded or thermal formed polymer part which is secured to frame  54  to provide support and maintain the chute in shape.  
         [0023]     Sheet  52  is formed into its chute shape by engagement with plate elements  80 ,  82  of frame assembly  54 . Plate element  80  is generally U-shaped while plate element  82  is generally planar. Sheet element  52  is retained between plate elements  80 ,  82  by fasteners  84 .  FIG. 3  illustrates the various components of discharge assembly  50  prior to assembly. As the plate elements  80 ,  82  are brought together during manufacture, sheet element  52  is formed into a predetermined shape by engagement with side elements  86  of plate element  80 . Frame assembly  54  may be considered a forming element for imparting a shape upon sheet element  52 . In a preferred embodiment, frame assembly  54  provides a clamping assembly for engaging and forming sheet element  52  into its chute shape.  
         [0024]     Frame assembly  54  includes a pair of frame arms  90  each connected at one end to plate element  80 . Hinge connection  56  includes frame arms  90 , pin  92  and cutting deck supports  96 . Pin  92  generally defines a hinge or pivot axis about which chute element  52  pivots. A biasing element  102 , here in the form of a torsion spring, provides a force tending to bias the deflector assembly into the guard position as indicated in  FIGS. 2 and 3 . If the discharge assembly  50  contacts an obstruction during mowing operations, hinge connection  56  allows discharge assembly  50  to pivot upward into an “unguarded” orientation. Once discharge assembly  50  is clear of the obstruction biasing element  102  helps return the chute into its guard position.  
         [0025]     Aspects of another embodiment of the present invention are illustrated in  FIG. 4 . Frame  54  includes a pair of brackets  100  defining a pair of configured surfaces  102  and a pair of hinge portions  104 . In this embodiment, the hinge connection is defined by the pair of hinge portions, a pin  92 , and the cutting deck supports  96 . In comparison to the embodiment of  FIG. 3 , this alternative embodiment incorporates aspects of the plate element  80  and two frame arms  90  into a pair of bracket  100  forming part of the hinge connection and also deflecting the sheet element  32  into chute shape.  
         [0026]     The term “frame” as used herein and in the appended claims is to be defined in the broadest sense. For example, the “frame” as used herein means a structure used to shape and support the resilient sheet  52  of the present invention. A frame may assume a variety of different shapes, e.g. the frame be generally U-shaped or L-shaped. A frame utilized in the present invention may or may not include planar sections, e.g., sections of the frame could be curved in form yielding a corresponding curved portion of the attached resilient sheet. A frame may be manufactured of a variety of materials, including but not limited to metals, plastics, composites, etc. Preferably, a frame is of a rigid metal (rigid, relative to the resilient chute). A frame may comprise a single part or multiple parts. Sections of the frame may be selectively movable relative to other sections of the frame, e.g. a frame may include two or more parts which are hinged together. In an illustrated embodiment, frame  54  is used to shape and support sheet  52  proximate to one end of sheet  52 . In alternative embodiments, frame  54  may include additional supporting elements which extend outwardly away from deck  28 . In such an alternative embodiment, frame  54  may include elements which engage top surface  60  and/or a bottom surface opposite the top surface. Frame  54  in alternative embodiments may have elements which pass through other apertures of sheet  52 . Frame  54  may include elements at which sheet  52  is adhesively secured thereto. One of ordinary skill in the arts would appreciate that a variety of different frame  54  devices or assemblies would be practicable to implement the present invention.  
         [0027]     Other variants are possible without departing from the scope of the present invention. For example, more than one sheet element  52  may be utilized, or the frame  54  may be differently configured to impart a different shape to the discharge chute. Thus, the scope of this invention is to be limited only by the appended claims.