GB2490511A - A lawn mower having two auxiliary cutters - Google Patents

Abstract

A lawn mower comprises a spinning rotor 2 which defines a primary cutting circle and at least two auxiliary cutters 1 each cutter defining a smaller cutting circle in use. The cutters maybe forward of the rotor in use. The mower may have three wheels one of which 3 may be positioned between the forward facing cutters. The mower may have at least one roller which may be positioned at the rear of the mower and the roller may be split into two parts which may rotate at different speeds.

Description

A LAWN MOWER CUTTING ARRANGEMENT

Held of the Invention The present invention relates to a lawn mower culling arrangement; more particularly a multi-mower arrangement that maximises cuffing functionality.

Bacçground Lawns or mown grass in general needs regular maintenance.

In particular in institutional or ground keeping situations, or more generally where the lawn has edges that need to be kept trimmed, much attention needs to be paid to trimming or culling neat and straight edges, lines and corners.

In particular corners may not be reached by a lawnmower that has a spinning blade describing a circle or arc, as This requirement for precise and controlled edge culling typically requires at least two pieces of apparatus, that is a general purpose lawn mower and a second edge trimming piece of apparatus, such as shears or an electric or motorised strimmer, spinning a piece of wire.

The requirement for two pieces of apparatus is cumbersome, costly and not preferable. Additionally strimmers, tend to not have any means of collecting strimmings, such that a rake is additionally needed, leading to more work and equipment.

Prior Art

Accordingly the following patent applications have been filed towards protecting apparatus that attempts to solve such a problem: Granted United States patent US 7 658 057 (O'DELL) discloses a lawnmower attached edger/trimmer, the lawnmower having a housing, a handle, a power source, a cutting blade, a shaft having the cuffing blade secured to a bottom end of the shaft, wherein upon activation of the power source said shaft begins to spin which in turn causes said cutting blade to spin, said lawnmower attached edger/trimmer comprising: a cutting member secured to the housing of a lawnmower, said culling member having a rotatable cuffing element; a drive member having a substantially planar upper surface secured to a blade support shaft of the lawnmower above a point where the cutting blade is secured to the shaft and below the power source; a contact member having a rotating portion, said contact member secured to the housing; a first rotatable cable having a first end and a second end, said first end of the first cable secured to the cutting member and the second end of said first cable secured to said contact member; an operating lever secured to a handle of a lawnmower; a second cable having a first end and a second end, said first end of the second cable secured to the operating lever and a second end of the second cable secured to the contact member; wherein upon activating power to the lawnmower the shaft begins to spin which causes said drive member to spin; wherein when the lawnmower is activated upon squeezing of said operating lever moves said contact member such that the rotating portion contacts the upper surface of said spinning drive member causing said first rotatable cable to spin which in turn causes the cutting element of said cutting member to spin.

Granted United States patent US 7 690 177 (SPITZLEY) discloses a string trimmer mechanism intended for mounting on a front end of a tractor comprising: a mounting structure for mounting on the front end of the tractor and including a plate member and a pivot pin extending forwardly from the plate member; a string trimmer assembly; and a trimmer positioning mechanism interconnecting the mounting structure and the trimmer assembly and including an extension power cylinder pivotally mounted at one end thereof on the pivot pin and connected at another end thereof to the string trimmer assembly and operative to move the trimmer assembly laterally relative to the pivot pin.

Granted European patent EP 1 958 496 (DEERE) discloses a shift mechanism for trim mower cutting units comprising a pair of lift arms, each lift arm mounted to a separate slidable carrier, each slidable carrier can slide along a pair of guide rods mounted to a mower frame; characterized by a pair of hydraulic extension cylinders, each extension cylinder connected to one of the slidable carriers and independently extending to move the slidable carrier laterally outward from the mower frame or retracting to move the slidable carrier laterally inward in relation to the mower frame; and a hydraulic shifting cylinder mounted between the two extension cylinders and extendable to shift both slidable carriers laterally inward toward a center position, and retractable to move both slidable carriers laterally outward toward an extended position.

Granted United States patent US 7 677 022 (CHENEVERT et al) discloses a convertible mower deck covering a plurality, preferably three culling chambers with a rotary culling blade in each chamber and a discharge opening from one of the culling chambers; characterized by a plurality of angled pivoting baffles between the culling chambers, each of the angled pivoting baffles being movable between an open position allowing flow of grass clippings between the culling chambers, and a closed position blocking flow of grass clippings between the cutting chambers.

European patent application EP 1 716 734 (KUFNER) discloses a lawn mower with an edge culling unit comprises an additional drive pulley located between the motor and the culling tool, and a front extension of the mower cover for the edge cutting unit. An independent claim is also included for an edge culling unit for the proposed lawn mower.

United States patent application US 2005 044 834 (APPLEYARD) discloses a lawnmower and trimmer apparatus comprising: a lawnmower having a deck a skirt depending therefrom, a plurality of wheels mounted to the deck, and a blade mounted on a rotatable power shaft beneath the deck, the skirt having a longitudinal slot defined therein extending between a front wheel and a rear wheel; a trimmer housing disposed on the deck; a trimmer culling head mounted below the deck adapted for dispensing a cutting filament through the slot; and means for selectively rotating the lawnmower blade alone and for rotating the lawnmower blade and the trimmer cutting head simultaneously; whereby the apparatus can cut grass and simultaneously trim grass German patent application DE 10 038 939 (IPPISCH) discloses an extra cutter bar fastens on a support as a grass trimmer or clean cutter and can mow an area at the side and in front that cannot be mown by a grass mower because of technical reasons. This extra cutter bar also fastens on a lever swiveled by Bowden pull wire and can be swung out or in when not in use. The extra cutter bar is driven by the grass mower's motor using a V-belt pulley on a drive shaft.

Granted European patent EP 0 959 660 (GUST) discloses a mower comprising: a traction vehicle; a plurality of cutting units carried on the traction vehicle which cutting units collectively cut a swath of grass as the traction vehicle is operated, wherein the cutting units comprise rotary-type cutling units each having a cutting blade which is rotated in a substantially horizontal cutting plane, wherein the cutting blade has a tip at each end with a sharpened cutting edge on each blade tip; wherein each cutting unit includes a cutting deck having a substantially circular shroud wall that extends vertically downwardly from a top wall to form a substantially circular, downwardly facing cutting chamber, wherein the cutting blade rotates within the cutting chamber without having the blade tips radially extend outside of the shroud wall of the cutting chamber and with the blade tips remaining at all times beneath the top wall of the cutting chamber; wherein each cutting unit includes a plurality of rotatable ground engaging members that allow the cutting unit to roll over the ground during movement of the traction vehicle; wherein each cutting deck has a front side that is forwardmost taken with respect to forward motion of the traction vehicle with the front side of the cutting deck having a pair of laterally spaced front corners comprising a left front corner and a right front corner; and wherein the cutting deck has a pair of front comer cut-outs comprising a left front corner cut-out located at the left front corner of the cutting deck and a right front comer cut-out located at the right front corner of the cutting deck, wherein each front corner cut-out is formed by a cut away portion of a lower edge of the shroud wall, the cut away portion extending high enough up the shroud wall such that an upper edge of the cut away portion is located below the top wall of the cutting deck but above the sharpened cutting edges on the blade tips so that uncut grass can more easily enter the cutting chamber through each front cut-out to be cut by the blade.

United States patent application US 5 465 564 (KOEHN et al) discloses a mower deck which is convertible between a discharge configuration wherein grass clippings are discharged from the deck and a mulching configuration wherein grass clippings are comminuted within the deck, the mower deck comprising: a housing, said housing having a discharge port for discharging grass clippings from said housing when the deck is in its discharge configuration; a plurality of elongated, vertically extending spindles rotatably mounted to said housing and adopted to be drivingly coupled to a drive mechanism; a culling blade for each spindle, said blades being attached to their corresponding spindles; a removable shroud which can be attached to and removed from said housing, the mulching configuration of the deck corresponding to the configuration of the deck with said removable shroud attached to said housing, and the discharge configuration of the deck corresponding to the configuration thereof with said removable shroud detached from said housing; a fixed shroud attached to said housing in disposition wherein the culling path of said blade is substantially enshrouded by a combination of said fixed shroud and said removable shroud when said removable shroud is attached to said housing; and at least one baffle for each blade, respectively, each baffle being attached to said removable shroud, said baffles being positioned substantially perpendicular to the culling path of its respective blade so that the baffles facilitate zones of turbulence in the airstreams created around said blades, whereby said zones of turbulence permit grass clippings to drop to the ground.

Granted European patent EP 0 541 611 (BAUMANN et al) discloses a multi-bladed mulching mower, which comprises: (a) a cutting deck which may be operatively connected to a traction unit for moving the cutting deck over the ground, the cutting deck having an underside facing the ground; (b) a plurality of substantially horizontal cutting blades rotatably carried beneath the cutting deck spaced below the underside of the deck; (c) shroud means extending downwardly from the deck, wherein the blades are located within the shroud means and the shroud means is shaped to confine the circulation of the grass clippings to areas of the cutting deck adjacent the cutting blades; and (d) deflecting means above the cutting blades and within the shroud means to deflect grass clippings downwardly into the path of the blade for eventual disposal in the cut grass path.

Granted European patent EP 0 119 339 (GULLETI) discloses an apparatus for mowing a lawn and trimming edges comprising, in combination, a wheel-supported central rotary pulley-type mower having a housing with a guard extending around the lower part thereof and wheel-supporting means supporting said housing for movement of said mower, said guard having a plurality of gaps therein, retractable guard elements for covering said gaps, means for retracting said guard elements, a rotary shaft pulley rotatably supported within said housing, means for rotating said pulley, a plurality of whip blade elements arranged peripherally underneath said housing, selected whip blade elements being cooperatively arranged with respect to said gaps and each whip blade element having at least one whip blade, and belt means for turning said whip blade elements.

In contrast the present invention provides a simple arrangement of cutting means, wherewith greater coverage, control and tidiness of cutting may be achieved.

Sjjçnnary of the Invention According to the present invention there is provided a lawn mower cutting arrangement including: a rotor spinning in use to define a primary cutting circle, and at least two auxiliary cutters spinning in use to describe smaller culling circles.

In this way the cutters are able to cut grass that ordinarily is unreachable by a mower, typically the corners of a square defined by a centre of the circle defined by the rotor centre.

In order to help facilitate this arrangement it is preferable that the mower is provided with a central wheel or roller between two smaller cutters with two rear wheels I split roller so as to create a three point mobility arrangement. Throughout, the terms wheel and roller may be read interchangeably and the use of either or both depends upon embodiment.

Such a wheel or roller arrangement allows for greater manoeuvrability in use, with the cutters being positioned to cut grass where in conventional mowers front wheels are located, which hinder the user's cutting freedom.

Typically the auxiliary circles are completely formed outside the primary circle.

However in some embodiments it may be envisaged that the auxiliary circles interlace with the primary circle.

In preferred embodiments where the mower has a first forward direction of movement, in which the mower typically moves, this direction defines where the smaller cutters are located on the mower.

Typically the cutters will be located on the forward direction of the rotor.

Furthermore it is envisaged that the cutters will be located to either side of the rotor, wherein the sides are defined by the forward direction.

In further embodiments it may be possible to include yet further cutters, such as to describe further circles, situate to interlace with or augment the mower's cutting efficiency and range. These may include still smaller cutters.

These cutters may be blades or strings as appropriate and preferable. It is envisaged that some embodiments of the invention may include a combination, wherein for example the main rotor carries a blade and the smaller cutters are rotating plastic strings, which feed out of a bundle common to hedge trimmers and the like.

Additionally by placement of the cutters in relation to the main rotor it is possible to ensure that by cyclonic effect any trimmings or cuttings are all passed through the body of the mower, to be collected at a box or collector, thereby ensuring minimal mess. This box may be situated above a rear roller in any embodiments that use rollers instead of wheels.

It is envisaged that the mower arrangement is preferably for a manually operated mower for pedestrian users however the arrangement is equally applicable to automatic or motorised mowers.

The arrangement is in turn equally applicable to electric and internal combustion mowers.

Some embodiments of the arrangement may combine a central petrol driven rotor with electrically driven cutters.

Brief Description of FiQures

Figure 1 shows a preferred embodiment of the invention from beneath; Figure 2 shows an isometric view of the embodiment from beneath; Figure 3 shows the embodiment from above; And Figure 4 shows a front view of the embodiment.

Detailed Description of Fkgures

The pictured embodiment is a three wheeled, three bladed lawn mower, designed to be able to cut close to fences or the like, cut edges and get into tight spots more easily than a regular lawn mower, and without falling off lawn edges when negotiating them.

The pictured embodiment has wheels to the rear, but it is clearly envisaged that substitution of a single wheel, more wheels, roller or split roller or other arrangement for providing mobility may be included in the invention.

In the pictured and preferred embodiment, two small (i.e. 6 inch diameter, wherein the rotor is 18 inch diameter) culling blades or cutters (1) are situated at the front or forward end of the mower wherein said cutters I in use describe circles or arcs that protrude outside a line defined by the main culling rotor blade (2).

Such an arrangement additionally reduces the risk of the mower falling into sunken flower beds as it is overbalanced in order for a user to position a central blade correctly for culling or trimming edges. Accordingly wheel or roller dimensions are calculated in order to accentuate this benefit.

Preferred embodiments of the lawn mower could be either electric or petrol engine lawn mowers. As pictured the mower has a robust and chunky front wheel 3 for stability and two rear wheels 4.

The cutters I could be changed from or to plastic strimmer wire or string, or metal blades either by a user or at manufacture. Accordingly a mechanism for disengaging the cutters is envisaged, preferably involving easy clip fit and/or resiliently deformable members.

ln the pictured and preferred embodiments a belt (not shown) connects the rotor 2 with the cutters 1, and a belt pulley (not shown) is provided to operate the belt. At least one pulley is ideally sprung to allow the user to easily stretch the belt over the pulleys. The belts and pulleys are not visible as they are hidden by a removable belt cover (100).

In use the spinning rotor blade 2 and/or cutter(s) I create a cyclone effect, collecting grass cuttings, passing them backwards through channels 5 and moving them via a grass cuttings exhaust (6) to the grass box (7).

Clutch plates may allow the mower engine (9) and body (10) to be separated, when there is a need to get inside the mower. The plates also allow for snags as the clutch will just slip causing less damage. There are clutch plates on the base of the engine (9) and on the body (10).

Preferably the engine (9) is mounted to the body (10) and a drive shaft (20 in Figure 3) takes rotary motion from the engine 9 to the small cutters I and main rotor blade (2).

In order to separate the engine 9 from the body 10 it is necessary in the pictured embodiment to disconnect the drive shaft 20 so preferably the drive shaft is separated or intersected by a separation clutch wherein one plate is attached to driveshaft towards the engine and the other to the driveshaft towards the rotor.

Such an arrangement has two purposes; one being easy disconnection of drive (as when the engine 9 is lifted the two plates separate) and secondly it also allows for if the cutters get blocked or snagged when the plates will slip, causing less damage.

A built in handle 11 allows the user to pull the engine 9 back into place.

Ideally the mowers cutting height is adjustable, typically by adjustment of the back wheels (4). This may be by means of ratchet or other reversible means for adding to or reducing the height of the mower body (10) in relation to the wheels (4).

Accordingly the cutters (1) and rotor (2) as mounted on the mower body 10 will be adjusted in height of cutting.

Alternatively, or in addition the height of the front wheel may be adjusted, such as by a lever and cable to a vertical lever that is attached to a horizontal arm supporting the wheel with a gas strut for stability.

In some embodiments a different wheel configuration may be envisaged, such as for example whereby the mower is manoeuvrable from the rear and a central rear wheel is flanked by the smaller cutters. Alternate embodiments may have a roller at the rear or front.

The lawn mower will not start unless a locking bolt (12 as shown in Figure 4) and the engine (9) are secure.

Ideally the engine may be flexibly or adjustably mounted in order that the engine (9) may be pushed back to allow access to the belts (not visible).

For example if a user is experiencing problems with the drive belts and needs to gain access to them, they must firstly release the locking bolt (12).

Releasing this lock automatically kills the engine, stopping the mower from functioning. In the pictured and preferred embodiment the user must use the handle (11) on top of the engine, and pull the engine back.

The user now has access to the internals and will need to remove screws that are holding the belt cover in place and take away the belt cover.

The user now has access to the drive belts (not visible). To change a belt in an embodiment such as the pictured embodiment the user must stretch the belt over pulleys. The pulleys are sprung to allow the belts to be stretched over more easily.

Once done the user places the belt cover (100) back, securing it using the screws and rotate the engine back down wherein the engine snugly fits and the clutch plates will re-engage. The engine 9 must be secured using the locking bolt 12. The engine will not start until the engine is locked in place and is secure.

To change the mower cutting height, the user must: pull the wheel height adjustment handle (13) towards the wheel (4), releasing the lock; move the handle (13) to one side, lowering the wheels (4), thus increasing the cutting height; and once the cutting height has been chosen, push the handle (13) back towards the mower, locating the handle in a locking hole.

Alternatively the user may adjust the height of the culling by internal mechanisms and controls, affecting the blade and/or cutter heights.

A grass catcher or scoop may be provided on some embodiments, such as a small horizontal scoop or raised section of the mower body on the forward facing side of the cutter's housing which preferably allows or encourages grass to enter towards the cutters, even if the grass is longer. This is pictured in the preferred embodiment as an indented section (101 on Figure 4). The purpose of such a scoop or lacuna would be to direct or collect grass into the cutter, for example rather than allowing it to slip around the cutter housing.

Claims (6)

1. ciaims 1. A lawn mower cuffing arrangement including: a rotor spinning in use to define a primary cutting circle, and at least two auxiliary cutters spinning in use to describe smaller cutting circles.
2. 2. A mower cuffing arrangement including to claim I wherein the cutters are situate to a forward-facing side of the rotor in use.
3. 3. A mower according to claims I or 2 wherein the mower has three wheels.
4. 4. A mower according to claim 3 wherein the mower has a front wheel between the auxiliary cutters.
5. 5. A mower according to claims I or 2 wherein the mower has at least one roller.
6. 6. A mower according to any preceding claim wherein the cutter and rotor are connected by at least one channel to a collector.A mower according to claim 4 wherein the roller is split into parts, wherein the parts may rotate at different speeds, and it is provided to the rear of the mower.