Abstract:
A lawn mower includes a base, a motor that drives a cutting assembly, and a catcher removably coupled to the base. Grass is cut by the blades of the cutting assembly, with the grass being propelled along a channel extending angularly beneath the base of the lawn mower. An exit channel portion delivers the cut grass to a rear opening that communicates with the catcher. A pivotally mounted flap opens and closes the exit channel portion to switch the lawn mower between a catching operational mode and a mulching operational mode.

Description:
This application claims priority to PCT/AU2008/001745 filed Nov. 26, 2008, which claims priority to Australian Patent Application No. AU 2008900090 filed Jan. 9, 2008. 
     TECHNICAL FIELD 
     The present invention relates to lawn mowers and more particularly to lawn mowers that provide a mulching function. 
     BACKGROUND OF THE INVENTION 
     Lawn mowers, including push and self propelled lawn mowers, have a base upon which there is mounted a motor. The motor may be an internal combustion engine or an electric motor. The motor drives a cutting assembly that includes a plate (disc) to which there is attached a plurality of blades. The plate is rotatably driven about a generally upright axis, with the blade being pivotally attached to the plate for angular movement about axes generally parallel to the upright axis. The blades as they are rotated about the generally upright axis engage grass to cut the grass. The grass is propelled angularly beneath the base along a channel in the base. Mulching mowers cause circulation of the cut grass around the channel to cause the grass to engage the blades a number of times to mulch the cut grass. The cut grass is then urged down into the freshly mown lawn. 
     In contrast to the above, frequently mowers are merely equipped with a catcher that collects the cut grass, with the cut grass then disposed of. 
     More recently mowers have been equipped with means via which they are able to operate in a “catching” mode or a “mulching” mode. The lawn mowers being changed in respect of mode by insertion or the removal of a “plug” that closes off the passage leading to the catcher. The “plug” completes a portion of the base that provides a channel along which the cut grass is circulated to be mulched. This type of mower has the disadvantage that the mower cannot be operating at the time the “plug” is inserted or removed. Accordingly, the mower cannot be changed between the two modes of operation while the mower is operative. 
     Also known are mowers having the two mentioned modes of operation, in which there is a plate that is selectively movable to provide for the delivery of grass to the catcher. The plate is also positionable to cause the mower to operate in a “mulching” mode. 
     Examples of the above mowers are described in Australian Patent Specifications 2003203292 and 2003203338. In both these instances it is difficult to change the mode of operation of the mower while the mower is still operative. 
     OBJECT OF THE INVENTION 
     It is the object of the present invention to overcome or substantially ameliorate the above disadvantage. 
     SUMMARY OF THE INVENTION 
     There is disclosed herein a lawn mower including: 
     a base providing a guide channel for cut grass; 
     a motor mounted on the base; 
     a cutting assembly rotatably driven by the motor about a generally upright axis, the assembly being driven to cut grass and to cause the grass to circulate angularly about said axis along said channel; 
     a catcher to receive the cut grass from said channel; and 
     a flap pivotably mounted for angular movement, about a pivot axis generally normal to said upright axis between a first position and a second position relative to said channel, said flap in said first position permitting cut grass to exit said channel for delivery to said catcher, while in said second position directing the cut grass to continue along said channel. 
     Preferably, said flap is resiliently urged to said first position or said second position. 
     Preferably, said flap is resiliently urged to said second position. 
     Preferably, said lawn mower further includes a handle extending upwardly and rearwardly from said base that is gripped by a user to aid in directing movement of the lawn mower over a lawn surface, and a user manipulated member movably mounted on the handle and used by the operator to move the flap. 
     Preferably, said user manipulated member is a lever pivotally mounted on said handle, and said lawn mower further includes a cable extending between said lever and said flap so that movement of said lever results in movement of said flap. 
     In an alternative preferred form, said user manipulated member is a slidably movable actuator, and said lawn mower further includes a housing within which said actuator is slidably moved. 
     Preferably, said actuator is longitudinally slidably movable within said housing and is angularly movable to locate said actuator in a selected position locating said flap in a desired position. 
     Preferably, said lawn mower has a pair of rear wheels that are rotatable about a wheel axis, with said pivot axis being generally parallel to said wheel axis. 
     Preferably, said flap is adjustably movable between the first and second positions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein: 
         FIG. 1  is a schematic rear perspective view of a lawn mower; 
         FIG. 2  is a front schematic perspective view of the lawn mower of  FIG. 1 ; 
         FIG. 3  is a schematic sectioned side elevation of portion of the lawn mower of  FIGS. 1 and 2 ; 
         FIG. 4  is a schematic bottom plan view of the lawn mower of  FIGS. 1 and 2 ; and 
         FIG. 5  is a schematic isometric view of an actuator employed in the lawn mower of  FIGS. 1 and 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the accompanying drawings there is schematically depicted a lawn mower  10 . The lawn mower  10  has a motor  11 . In this embodiment the motor  11  is an internal combustion engine. However it should be appreciated that other motors may be employed, including electric motors. 
     The lawn mower  10  of the accompanying drawings is a “push” mower. However in the present instance the mower  10  may also be a self propelled mower. 
     The mower  10  includes a base  12  upon which the motor  11  is mounted, with the motor  11  having a generally upright central rotational axis  13 . The motor  11  includes an output drive shaft  14  also having as its axis the rotational axis  13 . Attached the shaft  14  is a cutting assembly  15  that includes a disc  16  fixed to the shaft  14  so as to rotate therewith about the axis  13 . The disc  16  extends radially outward from the shaft  14  and has at least two blades  17  that engage the grass to cut the grass. The blades  17  are pivotally attached to the discs  16  for angular movement about axes  18  that are upright so as to be generally parallel to the axis  13 . 
     The base  12  has a central aperture  19  through which the shaft  14  projects. Surrounding the aperture  19  are mountings  20  to which the motor  11  is attached. The base  12  also has a channel  21  extending angularly about the axis  13  to which cut grass is delivered by the blades  17 . Preferably the channel  21  follows a circular path. The blades  17  cause the cut grass to move angularly about the axis  13 , as well as downward into the cut grass when operating in a “mulch” mode. The channel  21  has an exit channel portion  22  that extends rearwardly towards the rear opening  23  of the base  12 . 
     Attached to the base  12  so as to extend from the rear opening  23  is a removable catcher  24 . The catcher  24  has a front opening aligned with the channel portion  22  so as to receive cut grass therefrom. 
     The base  12  is supported on four wheels including two rear wheels  25  that may be driven in the instance where the mower  10  is self propelled. The wheels  25  are supported by a transverse rear axel  26  providing the wheels  25  with a rotational axis  27 . 
     Attached to an extending upwardly from the base  12  is a handle  28  that is gripped by a user at the upper end thereof to direct and/or propel the lawn mower  10 . 
     The base  12  has a radially outer skirt  29  that at least partly defines the channel  21 . 
     Attached to and supported by the base  12  is a flap  30 . The flap  30  is mounted on a transverse shaft  31  that provides a pivot axis  32  for the flap  30 . The axis  32  is generally normal to the axis  13  (but displaced therefrom) and is therefore generally horizontal when the mower  10  is positioned on a generally horizontal surface. The flap  30  is operatively associated with the channel portion  22  so as to selectively close the rear opening  23  that provides communication with the interior of the catcher  24 . More particularly the flap  30  is movable angularly about the axis  32  between a closed position at which the flap  30  is generally upright at least substantially closing the channel portion  22 , and an open position at which the flap  30  is generally horizontally oriented so as to provide for the flow of cut grass to the interior of the catcher  24 . However it should be appreciated the flap  30  can also be located in any desired position between the closed and open positions therefore providing for adjustment in respect of the volume of cut grass being delivered to the catcher  24 . When closed the channel portion  22  is closed by the flap  30 , the cut grass is caused to circulate about the channel  21  thereby causing “mulch” of the grass cuttings. As the flap  30  is moved to the open position at least some of the grass is ejected so as to be delivered to the interior of the catcher  24 . 
     Wound about the shaft  31  is a coil spring  33  that urges the flap  30  to a generally upright position closing the channel portion  22 . 
     Pivotally mounted on the handle  28  is a lever  34  that is pivotable about an axis generally parallel to the axis  27 . The lever  34  is manipulated by an operator to cause movement of the flap  30 . Attached to and extending from the lever  34  is a cable  35  that extends to the flap  30 . By causing pivoting of the lever  34 , the flap  30  is moved between the first and second positions thereof, or any desired position therebetween. Preferably the flap  30  is adjustably movable through 90°. 
     As best seen in  FIG. 4 , when the flap  30  is closed, the cut grass is caused to circulate about the channel  21  in the direction of the arrows  36 . When the flap  30  is opened so as to provide for the delivery of grass to the interior of the catch  24 , the grass travels in the direction of the arrows  37 . 
     In  FIG. 5  there is schematically depicted an alternative arrangement to the lever  34  of  FIG. 3 . In this embodiment a slidably movable actuator  38  is coupled to the inner cable of the cable  35 , with the outer sheath thereof attached to the housing  39  within which the actuator  38  is slidably captively located. The outer sheath of the cable  35  is attached to a connector  40  mounted on the housing  39 . 
     The housing  39  has a longitudinally extending passage  41  within which the actuator  38  is slidably located. The actuator  38  is longitudinally elongated and is slidably movable along the axis  42  extending longitudinally of the housing  39 . 
     The housing  39  has a plurality of “notches”  43  within which the handle  44  of the actuator  38  is locatable, to locate the flap  30  in a desired position. 
     Fixed to or formed integral with the housing  39  is a mounting bracket  45  that is attached to the handle  28  by fasteners.