Patent Publication Number: US-5022220-A

Title: Mulcher

Description:
This application is a continuation-in-part of my copending application Ser. No. 453,568, filed Dec. 20, 1989, now U.S. Pat. No. 4,969,321, which, in turn, is a continuation of application Ser. No. 47,372, filed May 6, 1987, now U.S. Pat. No. 4,912,917, issued Apr. 3, 1990. 
    
    
     TECHNICAL FIELD 
     This invention relates to mulching devices and arrangements. 
     BACKGROUND ART 
     Arrangements for producing useful horticultural mulch have been known and previously proposed, for example from U.S. Pat. Nos. 3,908,914; 4,150,796 and 4,169,561; also from West German patent specification No. De-A-3,404,733. 
     A typical known device or arrangement, as available on the market, or as previously proposed, has a cutting circle of perhaps 100 mm to 150 mm diameter, the blades usually being driven by, for example, an electric motor or other suitable prime mover. Prior art arrangements suffer from a number of disadvantages, even though many are quite expensive to purchase. For example, there is a difficulty in some arrangements, with engaging such an arrangement with a motor mower, and thereafter maintaining the motor mower and mulcher in a predetermined position relative to each other and at a predetermined angle relative to the ground. In a number of cases prior art arrangements frequently become clogged with vegetable matter such as for example leaves or cuttings, particularly when wet. This detracts substantially from the effective use and operation of such arrangements. Further, some arrangements suffer from inadequate means of passing vegetable matter to be mulched from a hopper to the area where the mulching takes place. 
     It is therefore an object of at least one aspect of this invention to go at least some way towards overcoming or at least minimizing the problems outlined above. Other objects of the present invention will become apparent from the following description. 
     SUMMARY OF THE PRESENT INVENTION 
     According to one aspect of this invention there is provided a mulching arrangement comprising a base plate an upper surface of which is adapted to mount mulching means; and including a feed hopper attached thereto and being adapted to receive vegetable matter to be converted to mulch; an aperture being provided in said base plate; means being provided to allow said base plate to be held in position above and at an inclined angle relative to, ground surface; said hopper including at least one feed inlet therein and an elongate base and feed passage; said feed hopper base being substantially planar and inclined downwardly at an angle relative to said ground surface; said feed passage extending into a mouth which communicates with said base plate; said feed passage being so formed and mounted relative to said base plate, that on operation of said mulching means, a vibratory moment is imparted therefrom to said feed hopper; the arrangement being such that vegetable matter is fed into said feed hopper through at least one feed inlet; said vibration imparted to said feed passage and the base of said feed hopper, combined with said downwardly inclined base of said feed hopper, enhancing passage of said vegetable matter therethrough and inhibiting or preventing clogging of vegetable matter as it passes over the base of said feed hopper and through said feed passage; said vegetable matter thereafter being drawn through the mouth of said feed passage by suction generated by operation of said mulching means, to enter a cutting and/or mulching zone of said mulching means and to be thereafter discharged therefrom. 
     According to a further aspect of this invention there is provided a mulching arrangement, comprising a base plate an upper surface of which includes or is adapted to mount mulching means, and including a feed hopper attached thereto and being adapted to receive vegetable matter to be converted to mulch; an aperture being provided in said base plate; means being provided to allow said base plate to be held in position above and at an inclined angle relative to, ground surface; said hopper including at least one feed inlet therein and an elongate base and feed passage; said feed hopper base being substantially planar and inclined downwardly at an angle relative to said ground surface; said feed passage extending into a mouth which communicates with said base plate; said feed passage being so formed and mounted relative to said base plate, that on operation of a lawnmower mounted on said base plate, a vibratory moment is imparted from said mulching means and base plate to said feed hopper; the arrangement being such that vegetable matter is fed into said feed hopper through at least one feed inlet; said vibration imparted to said feed passage and the base of said feed hopper, combined with said downwardly inclined base of said feed hopper, enhancing passage of said vegetable matter therethrough and inhibiting or preventing clogging of vegetable matter as it passes over the base of said feed hopper and through said feed passage; said vegetable matter thereafter being drawn through the mouth of said feed passage by suction generated by operation of said mulching means, to enter a cutting and/or mulching zone thereof and to be thereafter discharged therefrom; and wherein a pair of laterally spaced apart swingable arms are pivotally mounted to said base plate, one on each side thereof and both extending downwardly below an underside of said base plate; an elongate transverse axle shaft extending therebetween below, and being mounted to the underside of said base plate; and wheels being rotatably mounted at or adjacent distal ends thereof; lever means being connected to or formed with at least one of said arms; movement of said lever means to a position in substantial juxtaposition with said base plate moving said arms and wheels into a position relative to the base plate and the ground, whereby said base plate is adjacent and/or at a slight angle to the ground surface; further movement of said lever means to a predetermined position, moving the arms and wheels relative to the base plate such that the base plate is positioned substantially above the ground, at a predetermined or desired angle thereto, means being provided to releasably engage with said lever means such as to maintain said base plate in such a position substantially above and at an angle relative to, the ground, for a predetermined or desired period of time. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the reader may gain a better understanding of the present invention, hereinafter will be described some preferred embodiments thereof, by way of example only and with reference to the accompanying drawings in which: 
     FIG. 1 is a schematic side elevation of the mulching arrangement; 
     FIG. 2 illustrates a minor variation thereof; 
     FIG. 3 is a plan view Of FIG. 1; 
     FIG. 4 shows an alternative cutter bar; 
     FIG. 5 is a side elevation of a second preferred embodiment; 
     FIG. 6 is a fragmentary corresponding plan view; 
     FIG. 7 is a side elevation of a further embodiment; 
     FIG. 8 is a corresponding plan view; 
     FIG. 9 shows the attachment in a &#34;collapsed&#34; position; and 
     FIG. 10 is a fragmentary plan view showing the cutter bar arrangement in greater detail. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In one embodiment of the present invention a base plate 1 is provided which has a pair of ground engaging wheels such as 2. The base plate is preferably held at an angle above and relative to the ground or surface. The upper surface of the base plate 1 is provided with or is adapted to mount a mulching means. In this invention mulching means is an appropriate arrangement including a prime mover and rotating blades, which act so as to cut and mulch matter passed therethrough. For example, the mulching means could be in the form of a motor such as for example the motor used in a rotary lawnmower, connected to a drive shaft such as a substantially vertical drive shaft, adapted to rotate a number of blades about the vertical axis of the shaft, so that matter passing therethrough will be cut and mulched. Any appropriate form of engine or prime mover can be utilized to advantage; for example petrol-driven or electric motors. Control means can be provided in association with the engine and blades to allow the mulching means to be operated. If desired, the mulching means can be housed within an appropriate cover or housing. In one form of the invention, the mulching means can be fixedly mounted on to the base plate. In other forms of the invention the mulching means can be portable and can be placed on and removed from the base plate as desired. Appropriate securing means can be provided to locate the mulching means relative to the base plate. If desired, the mulching means can be provided with wheels to enable it to be portable. In use however it is important that the mulching means be mountable on and relative to the base plate so that matter passing through the mulching arrangement of the present invention is eventually passed through the operating blades of the mulching means so as to be cut and mulched, to be thereafter discharged as mulch. If an appropriate housing is provided about the motor and blades, an appropriate discharge port or means will be provided for discharge of said mulch. 
     In one form of the invention a land 5, being a substantially raised and partially circular land, extends at least partially about the upper surface of the base plate, and in the preferred form of the invention, the mulching means will be mounted on or located on the base plate such that it covers the mouth 6 of a feed passage (as will be described hereinafter). In this way, matter having been passed into the feed passage of the mulching arrangement of the present invention (to be described hereinafter) will pass through the mouth and into the cutting/mulching zone of the mulching means. 
     When the attachment is in use, base plate 1 rests at an angle θ to the ground, angle θ being from, say, 5° to perhaps 30°. Base plate 1 may be made of wood, particle board, metal, or a suitable plastic material. 
     Associated with the base plate 1 is a feed hopper 8, which is preferably formed of a plastic or similar resilient material. The feed hopper 8 communicates with the upper face of the base plate by way of a feed passage 9 at or adjacent the base of the feed hopper 8, a mouth 6 being provided and communicating with an opening or aperture in the base plate upper face. A primary feed inlet 10 of the hopper 8 may be provided with a hinged cover 11, and thus vegetable matter to be mulched is able to be fed into the hopper 8 through the feed inlet 10, to be passed through the feed passage 9 for discharge into the cutting region of the mulching means through the mouth 6. 
     The feed hopper 8 is preferably made of plastic, and if so, then the feed passage mouth 6 may be provided with or bounded by one or more cutter bar members 12 which are easily replaceable when they become worn by repeated contact with material being comminuted by the shearing action of mulcher blades against cutter bar means 12. Referring to FIG. 4 of the drawings, such a cutter bar 12 is shown and may have an additional center bar 13 to assist with fine comminution of vegetable matter. It should be appreciated that if desired a plurality of cutter bars 12 may be provided. 
     The feed passage 9 is preferably formed of plastic and is attached or secured to the base plate 8, about the mouth 6, in such a manner that when mulching means mounted or provided on the base plate 8 are duly actuated, the normal vibratory moment that is generated by operation of the prime mover of the mulching means will be imparted to the feed passage 9 which will therefore vibrate. It has been found that this is particularly advantageous in the present invention, as the vibratory moment imparted to the feed passage 9 causes the feed passage to vibrate while remaining attached to the base plate, and while remaining part of the feed hopper 8, the vibration substantially diminishing the chance of vegetable matter becoming clogged in the feed passage during a passage therethrough. As will be appreciated, wet vegetable matter has a tendency to become clogged and the vibration of the feed passage 9, by virtue of the formation of the feed passage 9 and its mounting relative to the base plate, will substantially inhibit or diminish such clogging. It has also been found that the vibratory moment as imparted to the feed passage 9 assists in actual passage of vegetable matter through the feed passage to the base plate. 
     Feed hopper 8 may be provided with an internal baffle 14 which stops just short of the base 15 of the hopper 8 to thus leave a secondary, front-opening feed inlet--the slit 16--through which such vegetable matter as cuttings and twigs, etc. may be fed for mulching. This secondary feed inlet slit 16 may be closed off by a hinged cover 17. While internal baffle 14 serves to guide, or channel, fed vegetable matter to the cutting region the feed hopper may be constructed with a similarly sloped front panel 18, as is to be seen in FIG. 2, in which case the secondary feed inlet is located as indicated at 19 and is closed off by a hinged cover 20. 
     A further embodiment is shown in FIGS. 5 and 6 of the drawings. 
     In this embodiment, all material to be comminuted into mulch is fed through a single opening 21 of a simplified hopper 8. The optimum angle 8 for the base of the hopper with respect to the ground is perhaps 15°, which promotes movement of material into the feed passage 9 where suction then conveys it into the cutting mulching region through feed passage mouth 6. Opening 21 of simplified hopper 8 may well optionally be provided with a hinged cover or lid 11. Long cutting, grass-stems, twigs, etc. are simply placed on the base 15 of feed hopper 8 and fed manually into feed passage 9 for suction into the cutting region at mouth 6. The base plate 8 is preferably mounted or positioned above and at an angle relative to the ground. 
     In a preferred embodiment of the present invention, as illustrated with particular reference to FIGS. 7 to 10 of the accompanying drawings, the mulching arrangement again comprises a base plate 101. In this form of the invention means are provided whereby the base plate can be moved from one position to another, for example from one position adjacent the ground and in which mulching means can be placed on or removed from the base plate with ease to another position in which the base plate is positioned and located substantially above the ground, with mulching means mounted thereon and at a predetermined or desired angle relative to the ground. 
     A pair of elongate and laterally spaced apart swingable arms 103 are provided, mounted on an elongate axle shaft 104 which extends transversely below an underside of said base plate 101, the axle 104 and ends of the arms 103 being housed or journalled such as in support means 104A, wheels 102 are mounted at each end of the laterally spaced apart arms 103, it being preferred that one arm 103 be provided on each side of the base plate 101. Lever means 105 are provided attached to and extending upwardly from one of the arms 103, so that movement of the lever 105 is capable of moving the arms 103 and wheels 102 into a first position in which, as shown for example in FIG. 9 of the drawings, the base plate 101 is adjacent to or positioned on the ground and in which position a mulching means is able to be placed onto or removed from the upper surface of the base plate 101 in a straight-forward and efficient manner. In such a position the lever 105 moves downwardly so as to be substantially flush with and in juxtaposition with the upper surface of the base plate 101. 
     The lever 105 is also so formed and mounted that it is capable of being moved so that it extends substantially upwardly from the swinging arms 103 and wheels 102 (such as for example shown in FIG. 7 of the accompanying drawings) in which position the swinging arms 103 and wheels 102 extend downwardly below the underside of the base plate 101 and maintain the base plate 101 in a position essentially above the ground and angled relative thereto at a predetermined or desired angle. 
     An abutment strut 105A is provided against which the lever 105 abuts in its position in which the base plate 101 is above and angled relative to the ground, appropriate releasable locking means being provided so that the lever 105 can be releasably held in position by or against the abutment 105A to hold the base plate 101 (together with any mulching means mounted thereon) in the raised and angled position. 
     When it is desired to return the base plate 101 to a position in juxtaposition with the ground (such as shown in FIG. 9 of the drawings), the lever 105 is released and is moved downwardly so as to move the arms and wheels downwardly into a position adjacent the underside of the base plate 101 into a position generally shown in FIG. 9 of the accompanying drawings. 
     It will be appreciated that the above has substantial advantages in that mulching means may be relatively heavy pieces of equipment and it may often be difficult to effectively mount such mulching means to base plates which are at a fixed raised and angled position. This form of the invention overcomes such a problem. When the base plate is in its lowered position such as shown in FIG. 9 of the drawings, a mulching means may be essentially wheeled or lifted into position above the base plate 101. This is however by way of example. When a mulching means is positioned on the base plate 101 in such a manner, and in the correct and/or desired position, it may be held and secured thereon by means of bolts, toggle clamps, over-center clamps and the like. 
     It should be appreciated that while the invention has been described by way of example only, with reference to a particular means for raising and lowering the base plate, relative to the ground surface, other means can be utilized to advantage. It should be appreciated however that it is particularly important that the base plate be at an angle relative to the ground surface and that means be provided to hold the base plate (and any mulching means provided or mounted thereon) at an angle inclined relative to the ground surface or horizontal. 
     The mulching means is not shown in the drawings, but wheels 106 and 107 are shown from a form of the invention in which the mulching mean can be provided with wheels to enable it to be portable from place to place. Where for example the mulching means is provided with a housing, the skirt of that housing might for example fit over the part-circular land 108 so as to cover mouth 109 at the feed passage. This will form a seal between the skirt and the base plate 101, and elastomeric annular gasket means may be provided within the land 108. The mulching means used in this form of the invention will preferably be as described by way of example only, with regard to earlier embodiments of the invention. The mulching means may be mounted directly to the upper surface of the mounting plate or can be releasably locatable relative thereto. The mulching means including an engine or prime mover and rotating cutting blades will provide a cutting/mulching zone on the base plate, so that matter passing from the feed passage of the mulching arrangement of the invention will pass into the cutting/mulching zone of the mulching means to be thereafter discharged as mulch. 
     In preferred forms of the present invention (with particular reference to FIG. 7 of the drawings), associated with base plate 101 is a feed hopper, generally referenced 110, ideally a plastic molding. Feed hopper 110 is in communication with the upper face of base plate 101 via a feed passage 111 and the said mouth 109. A primary feed inlet 112 of hopper 110 may have a hinged cover or lid 113 so that vegetable matter to be comminuted into mulch may be fed into hopper 110 through feed inlet 112 and which passes through feed passage 111 for discharge into the cutting and mulching region of the mulching means, via feed passage 109. 
     It has become apparent that the base 113A of the hopper 110 must be angled and inclined relative to the ground, the greater the angle between the base 113A of the hopper 110 and the ground, the better the feed characteristics. For example, leaves and the like have less tendency to bunch and obstruct the feed hopper and feed passage, and a faster transfer of material to the mouth 109 is attainable, the greater the angle between the base 113A of the hopper 110 and the ground. The optimum angle may be approximately the same as the angle of elevation of the base plate 101 with respect to the ground, and in certain forms of the invention the base plate 101 and base 113A of the feed hopper may be substantially parallel one with the other. The angle of inclination of the hopper base 113A relative to the ground, may vary but it has been found that an angle of about 15° will give a lower feed rate. On the other hand, an angle of perhaps 30° or more will give a considerably faster feed rate. The angle of inclination above the hopper base 113A can vary, and could for example be 45° relative to the ground surface. 
     Feed hopper 110 has a short &#34;neck&#34; 114 provided with a number of baffles, plates, or fins 15 projecting from wall 116; these are so dimensioned as to prevent entry of an operator&#39;s fingers into the cutting region. 
     In order to provide for the shredding and mulching of elongate vegetable material such as cuttings, twigs, vines, and the like not readily feedable to the cutting region through the primary feed inlet 112, there is a full-width secondary feed inlet 117 in the outwardly facing wall of hopper 110. The lower edge of this secondary feed inlet 117 is contiguous with hopper base 113A, and its height, while being sufficient to permit entry of vegetable matter to be comminuted, is still not great enough to allow an operator&#39;s hand to intrude into the cutting region. 
     The feed hopper 101 is preferably made of a plastic material or similar resilient material, and the feed passage 109 may well be bounded by a primary cutter bar 118, at or adjacent the mouth 109 thereof. However, the mulching blades may be enhanced by the provision of ancillary cutter bars 119, such as for example disposed radially with respect to the drive shaft of a mulching means. All the cutting bars may have hardened edges to prolong their cutting lives, or may alternatively be made from one of a number of forged, cast, fabricated metals or other suitable materials. 
     It is an important feature of the present invention that the passage of vegetable matter through the feed hopper is substantially assisted and enhanced by the combination of the downward inclination of the base 113A of the hopper and the vibration of the hopper (and the hopper base 113A and feed passage 111) having regard to the mounting of the hopper and feed passage to the base plate, in such a manner that when the mulching means is actuated, vibrations therefrom will be imparted to the feed hopper and thus to the base 113A of the feed hopper and to the feed passage 111. This vibratory moment causes the vegetable matter to vibrate and prevent or substantially diminishes clogging. The vibration, in association with the inclined planar surface of the base 113A substantially increases passage of matter through the feed hopper and diminishes substantially or avoids clogging of matter. When the vegetable matter reaches the feed passage 111, the action of the operating mulching means above the mouth 109 of the feed passage 111, will cause suction which will suck the vegetable matter up through the mouth into the mulching zone of the mower, whereafter the matter will be subjected to action of the blades of the mulching means, and thereafter discharged. 
     It will be appreciated that to operate the mulching arrangement of the present invention, the mulching means is provided on, or placed upon the base plate and (if appropriate) secured thereto by suitable means, so that any skirt of the mulching means or housing therefor is substantially sealed to or in juxtaposition with the upper surface of the base plate except at the discharge gap. For use, the base plate is raised above and relative to the ground at a predetermined angle, by operation of the lever means 105, the arms 103 and wheels 102. It will be appreciated that the wheels 102 allow the mulching arrangement of the present invention to be moved from place to place. Once the base plate is in its raised and desired position, the mulching means is started and this causes a vibratory moment which is imparted to the base plate and which is also imparted to the attached feed passage of the hopper. The matter to be mulched, such as vegetable matter, is passed through either one or both of the feed inlets of the hopper and is thereafter moved through the feed passage, clogging being substantially diminished or avoided by the vibratory moment imparted thereto. As indicated and described hereinbefore, the combination of the vibration of the feed hopper (and in particular the base thereof and feed passage) together with the downward inclination of the base of the feed hopper relative to the ground surface, contributes to and substantially assists in the passage of matter through the feed hopper, this also minimizing clogging of matter within the feed hopper. Where material to be mulched is of a generally small dimension, it will usually be fed into the primary feed inlet while the secondary feed inlet is closed. On the other hand, where material is in the form of twigs, cuttings and similar elongate matter, it may be fed into the secondary feed inlet. It has been found that by using the present invention, even tough material such as eucalypt leaves, bark, conifer cones and large twigs and canes are able to be converted into mulch. The selection of the appropriate feed inlet is of course at the discretion of an operator, depending upon the nature and size of the matter to be processed. 
     The mulching attachment is easily portable and light in weight, especially when its construction is of plastic. Moreover, it can be taken to the site of material to be mulched, being independent of electrical power outlets. The PG,17 efficiency and effectiveness of the present invention is high due to several advantageous factors, for instance, an average l/C-engined (for example from a rotary mower) when used in a mulching means, makes about 3.5 H.P. available for mulching as against the 1.5 H.P. of the electric motor of a conventional mulcher. There again the peripheral velocity of the mulcher blades can be approximately three times that of conventional mulchers for the same R.P.M. figure--that is to say, an average rotary mower has a cutting circle of about 450 mm diameter compared to perhaps a 150 mm diameter cutting circle of the conventional mulcher. The mulching attachment is largely self-cleaning and, as will be appreciated, the chances of the feed passage becoming clogged with green, and often wet, vegetable matter is substantially diminished. From the abovegoing it will be readily appreciated by those skilled in the art that numerous variations and modifications may be made to the invention without departing from the scope thereof, as defined in the appended claims.