Abstract:
A convertible mower deck which, in one embodiment, encloses the blade when it is in a mulching mode is provided. In a discharge mode, the deck provides one or more gaps, troughs or ducts through which cut material clippings can escape. The deck is convertible convert to a rear discharge mode by removal of a plug or insert that extends along the rear of the cutting chamber walls of the deck. The plug or insert is configured to seat into a slot, windfoil or ridge provided in the deck. A quick connect fastener at one end secures the plug to the deck. The ridge, windfoil or slot is flared outwardly and/or downwardly to provide a discharge opening. Because the material clippings in a discharge mode are permitted to exit through the opening(s) before they impact a mulch ramp deflector (on the underside of the mower deck or on the blade) the clippings “leak” out the opening and onto the top of the lawn or into a bag.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to a mower and more specifically to a mower deck that is quickly and easily converted between a mulching mode and at least a partial rear discharge mode.  
         [0002]     Many municipalities now require that grass cuttings be disposed of in an environmentally responsible manner. Frequently, this means that the homeowner must either pay additional sums to have the clippings bagged and removed from their site or dispose of them on their own. One solution has been to use a mulching mower deck that cuts and recuts the grass clippings and then drives them down into the standing uncut grass. In that way, there are no clippings to be collected and disposed.  
         [0003]     It may occur on occasion that a homeowner fails to cut the grass frequently enough to permit it to be mulched, for example, when the homeowner has been on vacation. In those situations, when the grass has grown too long to be mulched (for example, when the initial clippings would exceed one third the total grass blade length), the homeowner may prefer to simply cut and bag or discharge the grass cuttings onto the surface of the lawn. If discharged onto the lawn, the homeowner can then recut the grass in a mulch mode to mulch the precut clippings. To do so, the operator has to either use a different mulching mower, or if the homeowner has acquired a mower with a convertible mulch/discharge deck, convert the deck to the a mulch mode.  
         [0004]     Many of today&#39;s convertible mower decks require significant time, energy and tools to make the discharge/mulch or mulch/discharge conversion. Commonly, those mowers require a blade change as well as the removal of a baffle or mulch plug. Blades that are useful for mulching do not employ the lift contour at the end of the blade used by discharge blades to create a strong air current, which is necessary to propel the discharged cuttings out of the deck and especially into a bagging structure. Those non-contoured mulching blades have to be changed to a contoured discharge blade, so that the grass can be expelled sufficiently.  
         [0005]     Further, the mulch plug or baffle that is provided on the underside of the deck to deflect the cuttings down and into the standing grass must be removed to provide a discharge opening through the sidewall of the deck and through which the cuttings can be propelled. Removal of those plugs frequently requires tools and/or the opening of the deck to gain access to the plug. If the opening is in the side of the deck, the chute and objects projecting therefrom can hinder or prevent the mower from trimming on both sides thereof.  
         [0006]     It would therefore be desirable to provide a mower deck that is convertible between a mulching mode and a discharge mode. Specifically, it would be desirable to provide such a deck that does not require the changing of the blade, and in which the mulch plug could be quickly and easily removed without the need for tools, and wherein the mower can trim on both sides in a discharge mode.  
       SUMMARY OF THE INVENTION  
       [0007]     Toward those ends, the present invention provides a convertible mower deck that encloses the mowing blade when it is in the mulching or partial mulching mode. In a discharge mode, the deck provides one or more gaps, troughs or ducts through which cut grass clippings can escape. To convert the deck to a rear discharge mode requires merely the removal of a plug or insert that extends along the rear of the sidewall of the deck. The plug or insert is configured to fit into a slot, ridge or duct provided in the deck. A quick connect fastener at one end of the insert secures the insert to the deck. The quick disconnect fastener can be spring-loaded or otherwise configured so that no tools are required for connection, removal or replacement.  
         [0008]     The sidewall defining the ridge or duct is flared outwardly and downwardly to provide a discharge opening in the bottom of the deck in one embodiment. In another embodiment, an aperture is defined by the back side of the deck, wherein clippings are discharged horizontally out the back of the deck. In the discharge mode, because the grass clippings are permitted to exit through the openings before they impact a mulch hump deflector (on the underside of the mower deck or on the blade) the clippings leak or blow into the opening and onto the top of the lawn or into a bag.  
         [0009]     In one embodiment, the mower deck is configured to facilitate trimming on both sides thereof. Here, one or more discharge chutes are positioned at the rear portion of the deck so as to not interfere with trimming. The outer sides of the mower deck are identical or substantially identical in shape in one embodiment.  
         [0010]     Two primary embodiments are disclosed herein for the inserts and the openings made in the mower deck. In one embodiment, lower rear portions of the cutting chambers of the mower deck are bent or flared outward and downward from the edge of the blade to create an opening adjacent to the blade in the rear of the deck. In that embodiment, the grass clippings fall vertically out of the mower deck before being cut a second time or mulched. In another embodiment, portions of the rear ends of the cutting chambers of the deck are cut away, bent and formed so as to create a duct or airfoil opening in the sidewall of each of the chambers of deck. A windfoil or other type of directional member extends from opening to direct air and grass clippings towards a desirable destination.  
         [0011]     In one embodiment, the grass clippings are blown out the back of the mower deck on an angle towards a centerline of the lawnmower, so as to place the clippings behind the mower in a suitable position to be bagged by the mower or swept by a sweeper attached to and carried by the mower. To that end, the mower blade drives are configured to spin the blades in opposite directions, which causes the blades to provide a centripable force to the clippings exiting the duct so that the direction of the clippings exiting the deck is substantially in line with the windfoil or directional members extending from the openings in the back wall of the deck. The ducting and direction of the discharge chute force the clippings to blow towards the reward centerline destination.  
         [0012]     The inserts in one embodiment are inserted and removed readily via a single fastener or a quick disconnect per insert. The housing defines a slot or notch, which receives one end of the insert or a member extending therefrom. The other end of the insert is then attached via the fastener or quick disconnect. To remove the inserts, the fastener is removed or the quick disconnect is moved and the insert is slid, e.g., down and away from the notch or slot in the housing. The inserts are generally elongated horizontal members that are relatively “low profile” with respect to known larger side discharge covers. The low profile provides a rigid, strong insert that can withstand the rigors of mowing.  
         [0013]     In the partial discharge mode, some or the grass clippings are cut once and the blown from the deck. In the partial discharge mode, however, some of the clippings are recut or reprocessed, like a mulch. In one embodiment about half the clippings are mulched and half are discharged. The release of some of the clippings allows the mower to cut tall grass, continuously, without the mower becoming clogged or leaving behind clumps of grass. In a mulch mode, i.e., with the inserts in place, most all the clippings are reprocessed and mulched. It is therefore an advantage of the present invention to provide a mulching and discharge mowing deck for a lawnmower.  
         [0014]     It is another advantage of the present invention to provide a mulching/discharge mowing deck that is easy to convert back and forth from a mulching mode to a discharge mode.  
         [0015]     It is another advantage of the present invention to provide a mulching/discharge mower that blows grass towards a central destination behind the lawnmower, where it can be bagged by the lawnmower or swept by a sweeper that is pulled by the lawnmower.  
         [0016]     Yet another advantage of the present invention is to provide a mulching/discharge deck that does not discharge grass and other objects out the side of the lawnmower.  
         [0017]     Still another advantage of the present invention is to provide a mulching/discharge deck that enables the mower to trim grass against a dwelling or other structure with substantially the same degree of precision on both sides of the mower.  
         [0018]     Still further, it is an advantage of the present invention to provide a mulching/discharge deck for a lawnmower that does not require the removal and replacement of a mowing blade for converting the lawnmower from a mulching mode to at least a partial discharge mode and vice versa.  
         [0019]     Yet a further advantage of the present invention is to provide an insert for a mower deck that is rugged and durable to withstand forces produced via mowing. Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description of the Invention and the figures.  
     
    
     BRIEF DESCRIPTION OF THE FIGURES  
       [0020]      FIG. 1  is a bottom-side perspective view of a drive train and mower deck in one embodiment of the present invention.  
         [0021]      FIG. 2  is a bottom-side perspective view of one of the cutting chambers in one embodiment of the mowing deck of the present invention.  
         [0022]      FIG. 3  is a top plan view of a portion of one embodiment of the mowing deck of the present invention.  
         [0023]      FIG. 4  is a bottom plan view of a ridge portion of the mowing deck, which receives one of the inserts in one embodiment of the present invention.  
         [0024]      FIGS. 5A and 5B  illustrate one possible shape for the bent ridge and insert of the mowing deck in one embodiment of the present invention.  
         [0025]      FIGS. 6A and 6B  illustrate another possible shape for the bent ridge and insert of the mowing deck in one embodiment of the present invention.  
         [0026]      FIGS. 7A and 7B  illustrate a further shape for the bent ridge and insert in one embodiment of the present invention.  
         [0027]      FIGS. 8 and 9  are perspective views illustrating one preferred mower deck and shapes for the openings therein.  
         [0028]      FIG. 10  is a top-rear perspective view of one embodiment of the mower deck of the present invention showing the inserts removed slightly from one preferred opening and ducting therefore shown in  FIGS. 8 and 9  for discharging grass of the present invention.  
         [0029]      FIG. 11  is a bottom perspective view of the mower deck in one embodiment of the present invention illustrating the operation of the mulching blades in combination with mulch ramps placed in each cutting chamber of the deck shown in  FIG. 10 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0030]     Referring now to the drawings and in particular to  FIG. 1 , a drive train  10  for a riding lawnmower having a motor, engine or other power unit  11  supported by a frame  13  is illustrated. The seat and chassis have been removed for ease of illustration. Drive train  10  includes front wheels  12  supported rotably by front axle  14 . Drive train  10  also includes rear wheels  16  supported by a rear axle  18 . A steering wheel  20  is provided that connects pivotally to drive train  10  via a steering wheel shaft  22 . Controls, such as directional drive settings, speed adjust, gearing, breaking, cutting blade on/off and other control settings are controlled by control devices or controls  24 .  
         [0031]     In one embodiment, the present invention includes a dual blade lawnmower deck  50  located on the underside of drive train  10 . While deck  50  is illustrated operating with a riding mower, deck  50  is alternatively operable with any suitable lawnmower, walk-behind mower or other mowing machine, including walk-behind mowers with one, two or three cutting blades. As the drive train  10  of the lawnmower is propelled forward, the mower deck  50  proceeds along the ground, contacting the grass, plants, leaves and other materials to be mowed as is well known.  
         [0032]     Mower deck  50  includes a housing  52  that defines two mowing chambers  54  and  56 . Each of the chambers  54  and  56  defined by housing  52  is supported by a respective support wheel or roller  58 . Wheels  58  maintain the cutting blades inside chambers  54  and  56  of deck  50  at a relatively constant height above the ground when drive train  10  of the mower is in motion. Wheels  58  help to prevent scalping or uneven cutting when the mower meets a hill or elevation change.  
         [0033]     Drive members, drive shafts or spindles  62  are attached rotatably to the housing  52  substantially at the centers of chambers  54  and  56 . Blades  60  are attached to distal ends of spindles  62 .  FIG. 1  also shows discharge control devices or inserts  64  and  66  of the present invention that are attached to the rear portion of housing  52  in chambers  54  and  56  respectively.  
         [0034]      FIG. 2  illustrates more closely the chamber  54  of mower deck  50 , which is defined by a portion of housing  52 . Blade  60  is supported by spindle  62  via a nut and washer threaded onto spindle  62 .  FIGS. 1 and 2  illustrate discharge control device or insert  64 , which is removeably fixed inside the back half of chamber  54  when mower deck  50  and the lawnmower are intended to be operated in a mulching mode.  
         [0035]     Blade  60  is a mulching blade in one embodiment. Blade  60  has a bent configuration so that airflow created by blade  60  urges grass blades or other material at the end of the blade to stand up when cut a first time. The cut clippings are then moved by blade  60  and a mulch ramp (shown below) toward the inner portion of the blade, wherein the clippings are cut again. The blade is further configured at its inner portion to create a down-draft. The down-draft pushes recut or mulched clippings towards the ground and intersperses such clippings into the cut grass.  
         [0036]     One suitable blade for deck  50  and the lawnmower employing same is described in U.S. Pat. No. 5,191,756 assigned to the assignee of the present invention, the teachings of which are hereby incorporated by reference. That patent at  FIG. 4  shows a mulching blade with an updraft portion at the end thereof and an inner cutting edge which is humped or elevated above an outer cutting edge. The inner humped portion cuts the grass at a different height than does the blade at its outer edges. The different cutting levels cause the grass to be cut into smaller pieces, i.e., to be mulched. The inner portion is also configured to create a down-draft to drive the mulched clippings into the ground.  FIGS. 2, 5 ,  6  and  7  of that patent also describe a mulch ramp, which directs the clippings from the outside of the blade to the inside of the blade to be recut or mulched. Mulching blades without mulch humps are also suitable for operation with deck  50 .  
         [0037]      FIG. 3  shows a top view of one embodiment of one of the chambers  54  or  56  of deck  50 . A rear portion of the chamber  54  or  56  includes a sidewall  54   a  or  56   a , which defines a hollow ridge  68 . One of the inserts  64  or  66  is fitted and fastened into hollow ridge  68 , placing the mower in a mulch mode. The insert  64  or  66  is removed from hollow ridge  68  to allow some of the grass clippings in one embodiment to escape vertically downward in a partial discharge mode between the blade and the housing  52 . Some of the clippings drop away or “leak” from mower deck  50  prior to being cut again or mulched. Other clippings, e.g., from about zero (if ridge is large enough) to about eighty percent of the clippings are mulched, creating a hybrid mulch/discharge operating mode. Different shapes for ridges  68  are illustrated below.  
         [0038]     The discharge control devices or inserts  64  and  66  are blow molded or injection molded hard plastic in one embodiment. In another embodiment, inserts  64  and  66  are cut or stamped from aluminum or other light, strong metal. In a further embodiment, the inserts are formed or bent metal, such as formed steel or stainless steel. The material is rugged and withstands the pounding taken by deck  50  when the mower is in use. Also, as seen below, the inserts are relatively “low profile” and do not create a significant cantilever with respect to the sidewalks of chambers  54  and  56 . Consequently, the inserts and the assembly of the chambers and inserts are well equipped for the rigors of mowing.  
         [0039]      FIG. 4  shows one embodiment of ridge  68  into which insert  64  or  66  is fitted. Ridge  68  includes apertures  26  and  28  or other types of mounting structures for such attachment. Inserts  64  or  66  can be configured and oriented the same way or be made in a left and right pair configuration. In one embodiment, one end of the insert fits into a notch or slot, such as slot  28 , or other type of male or female structural support defined by ridge  68 . The other end of inserts  64  and  66  attach to the ridge  68  or housing  52 , e.g., via mounting hole  26  and a quick-disconnect type of fastener, such as a spring-loaded clip, a bolt and a wing nut, etc.  
         [0040]     The above-described configuration enables discharge control devices or inserts  64  and  66  to be readily fastened to ridges  68  or housing  52  by lodging one end of the insert  64  or  66  against or in the notch, slot or catch of ridge  68  or housing  52  and then fastening the other end of the insert  64  or  66  to the respective ridge  68  via the quick disconnect fastener. Attachment can therefore be performed in one step and with no tools. Likewise, to remove inserts  64  and  66 , the single disconnect is removed or moved and the insert is pulled away from the notch, slot or catch of the associated ridge  68 . Removal can also be performed in one step with no tools.  
         [0041]      FIGS. 5A  to  7 B each show different cross-sectional shapes for the inserts  64  and  66  and ridge  68 .  FIGS. 5A and 5B  show a square or rectangular shaped ridge  68 .  FIGS. 6A  to  7 B show ridges  68  positioned at various angles.  FIGS. 5A, 6A  and  7 A each show corresponding fitted cross-sections of inserts  64  and  66 . Each of the ridges  68  of  FIGS. 5A  to  7 B function as spacers, which serve to create a space or opening as seen in  FIGS. 5B, 6B  and  7 B that allows grass clippings initially cut to pass outside the end of blade  60  and fall to the ground without being cut twice or mulched, e.g., leak out the bottom of deck  50 . When insert  64  or  66  is placed inside ridge  68 , as seen in  FIGS. 5A, 6A  and  7 A, the insert functions as a space filler causing the clearance between the end of blade  60  and an inner surface of chambers  54  and  56  to be substantially the same around the entire circumference struck by the end of blade  60  (except where chambers  54  and  56  open into one another). Such consistent clearance, about one quarter inch (6.4 mm) in one embodiment causes the grass to be mulched by leaving little or no discharge gap. Consequently, when the blade  60  rotates, the space fillers or inserts  64  and  66  retain the grass on the top side of the blades for a suitable period of time to enable a mulching action to occur.  
         [0042]      FIGS. 8 and 9  are perspective views showing the underside of one preferred mower deck  50 . As illustrated, portions of the rear sidewalls  54   a  and  56   a  of chambers  54  and  56  of housing  52  are removed to create low profile openings that enable at least some of the grass clippings in a partial discharge mode to escape out of the back of deck  50  before being reprocessed, cut again or mulched. Some of the clippings in the partial discharge mode be recut or mulched. Depending of the height of the openings created by ducts  70  and  72 , more or less clippings will be discharged rather than mulched. It is possible to open deck  50  enough by making openings via ducts  70  and  72  high enough to create a total discharging mower mode.  
         [0043]     In one embodiment, the height of the openings created by ducts  70  and  72  is about {fraction (1/4)} inch (6 mm) to about 1 inch (25.4 mm), which varies the percentage of clippings discharged to those mulched. Larger or smaller openings are also contemplated by the present invention so that the percentage of clippings discharged to the total grass clippings created is from about zero percent to about eighty percent. In one preferred embodiment, about fifty percent of the clippings are mulched and fifty percent are discharged, which enables tall grass to be cut without stalling or clumping.  
         [0044]     Airfoils  82  and  84  extend from ducts  70  and  72 , respectively, and cooperate with the mower blades to direct and release air and clippings in an efficient and desired manner. Airfoils  82  and  84  extend from ducts  70  and  72  tangentially so as not to disrupt the momentum of the grass and air exiting the ducts  70  and  72 .  
         [0045]      FIGS. 9 and 10  are top and bottom views of one preferred configuration of mulching/discharge deck  50 , respectively, showing ducts  70  and  72  in cooperation with inserts  64 ,  66  and blades  60 . As discussed above, discharge ducts  70  and  72  replace the ridge  68  of the previous embodiments. Discharge ducts  70  and  72  enable grass clippings in the discharge mode to escape freely substantially horizontally from a removed sidewall portions  54   a  and  56   a  of deck  50  (as opposed to the opening defined at the bottom of deck  50  as seen in  FIGS. 5A  to  7 B). The discharge control devices or inserts for ducts  70  and  72  therefore block the grass clippings from exiting through the back of deck  50  as well as through the bottom of deck  50  as opposed to only through the bottom of deck  50  as seen in  FIGS. 5A  to  7 B. Here, the inserts  64  and  66  preferably function as discharge stoppers or closure members that actually create the lower back wall portions of housing  52  of deck  50 .  
         [0046]     Ducts  70  and  72  provide a more open and streamlined area or room for the grass clippings in the discharge mode to escape versus the ridge  68  of  FIGS. 5A  to  7 B. In the mulch mode, however, inserts  64  and  66  create again a constant clearance between the blade and the sidewalls of chambers  54  and  56 , except where those chambers open into one another. Inserts  64  and  66  complete the inner profile defined by chambers  54  and  56 , so that the clearance between the inner surface of the chambers and the mower blade remains substantially unchanged. Inserts  64  and  66  can extend from about 60 degrees to about 120 degrees about the outside of the chambers  54  and  56 . As seen in  FIG. 10 , inserts  64  and  66  bolt to or otherwise fasten easily to ducts  70  and  72 , respectively.  
         [0047]      FIG. 10  illustrates that a guide or member  74  extends from each insert  64  and  66  at a point located near the inner ends of the inserts. To attach inserts  64  and  66  to ducts  70  and  72 , respectfully, the first step is to insert a larger radius portion of members  74  through a larger diameter portion of a keyed aperture  76 . Once the larger diameter head of member  74  is inserted through aperture  76 , the inserts  64  and  66  are slidably moved against the ducts  70  and  72 , respectively, until a threaded hole  78  of inserts  64  and  66  comes into alignment with a mounting hole  80  provided on ducts  70  and  72 . Once holes  78  and  80  are aligned, a pin, screw, bolt or other type of fastener is used to fixedly attach inserts  64  and  66  to chambers  54  and  56  of the housing  52  of the mower deck  50 . Likewise, to remove inserts  64  and  66 , the fasteners are removed from threaded holes  78  of inserts  64  and  66  and the inserts are slidably moved in the opposite direction until the larger diameter portion of members  74  can be dropped through the larger diameter portion of keyed aperture  76 . While the method of attachment is easy to perform, the attachment system is sturdy and withstands the rigors of repeated and continuous mowing.  
         [0048]      FIGS. 10 and 11  illustrate that cutting chamber  54  is set slightly ahead of cutting chamber  56  with respect to the forward direction of travel of the lawnmower. The offset nature of the blades  60  within chambers  54  and  56  helps to insure a smooth overlapping cut provided by the dual blade lawnmower.  FIG. 11  also illustrates that the blades  60  travel in opposite rotational directions (as indicated by the illustrated arrows). The blade rotation is set to align the momentum or flux of air and grass exiting ducts  70  and  72  with the taper or direction provided by the associated windfoils  82  and  84 . Spoilers or airfoils  82  and  84  are arranged to be in line with the direction of the air path at the beginning of openings via ducts  70  and  72  created by blades  60 .  
         [0049]     As seen in  FIG. 10 , discharge chute or duct  70  includes a material director, spoiler or windfoil  82  that tends to direct air and grass clippings exiting through duct  70  towards a centerline running in the direction of travel of the lawnmower. The blade  60  as seen in  FIG. 10  of chamber  54  runs counter clockwise around spindle  62  and thus carries the grass along the outer edge of housing  52  of chamber  54  and throws the grass out along and through airfoil  82  towards the inner portion of the lawnmower. Likewise, discharge chute or duct  72  includes a material director, spoiler or windfoil  84  that directs air and grass towards the inner portion of the lawnmower. Blade  60  of chamber  52  in  FIG. 10  rotates clockwise and carries the air and grass clippings along the outer edge of housing  52  towards and through airfoil  84  of duct  72 . Airfoils  82  and  84 , therefore, cooperate to create a stream of grass that is placed relatively centrally behind the lawnmower. Again, at least in some embodiments, a portion of the clippings are recut or mulched when inserts  64  and  66  are removed. The portion that is not recut is carried along the sidewalls of chambers  54  and  56  and thrown out along airfoils  82  and  84  through ducts  70  and  72 , respectively. The portion that is recut is forced via the down-draft created by blades  60  to fall to the ground.  
         [0050]     In one embodiment, a material or grass catch or collector (not illustrated), such as a hopper, is attached to the lawnmower and communicates fluidly with ducts  70  and  72  so that grass is blown into the grass catch as is well known. In another embodiment, the lawnmower includes a hitch (not illustrated) that enables a lawnmower sweeper be pulled behind the lawnmower to sweep up and capture the grass clippings after being thrown from the back of the lawnmower opposite to the direction of travel of same.  
         [0051]      FIG. 11  illustrates that blades  60  and deck  50  cooperate with a material director or mulch ramp  86  fitted inside chamber  54  and a material director or mulch ramp  88  fitted inside chamber  56 . Mulch ramps  86  and  88  can be formed from a single piece or formed in separate pieces. In one embodiment, mulch ramps  86  and  88  are made of hard plastic. Alternatively, mulch ramps  86  and  88  are metal, such as steel or aluminum.  
         [0052]     Mulch ramps  86  and  88  cooperate with blades  60  and their respective direction or rotation to guide grass once it has been cut a single time towards an inner portion of the blade  60 , where the blade cuts the grass a second or third time. Blades  60  are shown having an irregularity, an elevation change or a mulch hump  90 , which cuts the grass clippings as they are pressed against mulch ramps  86  and  88  and forced across mulch hump  90  and towards the inner portion of the blades  60 . As discussed above, in connection with U.S. Pat. No. 5,191,756 the outer edges of blades  60  are oriented to create an updraft that stands the grass blades up to cut them initially. The inner portion of the blade  60  has a raised leading edge with a cutting blade to recut or mulch the initially cut clippings and a lowered trailing edge to create a down-draft to drive the mulched clippings into the ground. Mulching occurs when inserts  64  and  66  are installed and to a lesser extent when inserts  64  and  66  are removed (allowing some of the initially cut grass clippings to be thrown from and exit the back of deck  50 ).  
         [0053]     In another alternative embodiment, not illustrated, inserts  64  and  66  are combined to form a one-piece or integral discharge control device or insert that bolts or fastens in one or more places to a single duct or ridge provided in a middle portion of the back of an alternative deck, where the chambers  54  and  56  interface together. The blades  60  would then rotate in the opposite direction than the directions shown in  FIG. 9  to throw grass out the middle of the back of the deck when the one piece insert is removed.  
         [0054]     In operation of one embodiment, when inserts  64  and  66  are in place, the inserts inhibit or prevent the initially cut grass from escaping, and the grass is forced to be carried across ramps  86  and  88  for further cutting and mulching. The downward draft created by the middle portion of blades  60  then forces air and the mulched grass clippings towards the ground and between the remaining lawn blades extending therefrom. When inserts  64  and  66  are removed, however, at least a potion of or substantially all of (depending on size of openings via ducts  70  and  72 ) the initially cut clippings are carried by blades  60  along the outside edges of chambers  54  and  56  and are pushed out through ducts  70  and  72  via airfoils  82  and  84 , e.g., through the back out of deck  50 . That is, in the discharge mode, the initially cut clippings are not forced or directed against mulch ramps  86  and  88  for further cutting. The mulch ramps  86  and  88  can also be used with the bent ridges  68  described above.  
         [0055]     The discharge chutes or ducts  70  and  72  and ridge  68  described above have a relatively low profile with respect to large side discharge openings common to many known lawnmowers. The low profile helps to reduce noise from escaping from the chambers as well as to keep rocks and other particles from being thrown therefrom.  
         [0056]     It should be appreciated that the mower deck of the present invention can be installed and used on any vehicle, tractor, mowing machine, lawnmower, walk-behind lawnmower, riding lawnmower, string or blade-type trimmer or any other machine which mows, cuts, mulches, trims or shapes lawn, grass, weeds, plants, leaves or other materials.  
         [0057]     It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.