Note: Descriptions are shown in the official language in which they were submitted.
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CUITING SYSTEM FOR ROT~RY L~WN MOVVER
CROSS-REFERENCE TO R]ELATED APPLICATION
This application is a continl1~tion-irl-part of U.S. Ser. No. 08/671,333 filed
June 27, 1996.
TECHN~CAI FIELD
The present invention relates generally to a cutting system for a power
rotary lawn mower. More particularly, the present invention relates to baffles
10 that cooperate with a rotary mower blade to finely shred vegetation clippings.
Specifically, the present invention relates to a cutting system that includes a
plurality of baffles disposed above a rotary cutting blade that cooperate with
vertically-oriented mulching cutters that extend from the rotary blade to
repeatedly cut vegetation clippings.
BACKGROUND ART
In recent years the demand for mulching lawn mowers has greatly
increased. The demand has increased partially because the cost of l~n~lfilling
lawn clippings has caused some communities to ban curbside collections of lawn
20 clippings. Another reason is that a mulching mower eliminates the need for the
person mowing the lawn to collect the grass clippings and remove them from the
lawn, thus reducing the amount of time required to mow the lawn.
To effectively mulch vegetation clippings, a lawn mower must cut each
clipping multiple times. One problem with cutting the clipping multiple times is25 positioning the clippings so that the blade may repeatedly strike them. Typically,
once a blade of grass is cut, the clipping is forced up by the air flow pattern to the
area between the blade and the mower deck:. The clipping then may swirl above
-the blade briefly until it falls back down through the plane of the blade towards
the ground due to the influence of gravity a~nd air streams. The likelihood that30 the clipping will be cut again by the blade depends on the speed of the blade and
the size of the clippings and the random orientation of the clippings when passing
. . .
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through the plane of the blade. As a result, an undesirable number of clippings
fall back to the ground without being recut. It is thus desirable to provide a
cutting system that more predictably and reliably positions the clippings so that
they may be recut one or more times by the blade.
Many improvements have been made to rotary lawn mower blades to
facilitate mowing and related mulching or shredding action. Typically, the
improvements have been directed toward the geometry of the mower blade. For
instance, extra cutters have been positioned above or below the plane of the blade
to provide additional cutting surfaces. Another blade configuration has the endsof the blade bent upwardly so as to direct the clippings upwardly where they fall
back through the plane of the blade to be: recut. Still another configuration
includes multiple-armed blades having cutting surfaces disposed in different
cutting planes. These prior designs attempt to solve the problem of multiple
cuttings by increasing the chance that a clipping will be cut more than once
primarily by increasing the number of CUttiIIg surfaces.
DISCLOSURE OF TH]E INVENTION
In light of the foregoing, it is an object of the present invention to provide
a cutting system for a rotary lawn mower that predictably positions clippings sothat the probabilities that the cutting surfaces of a rotary mower blade will recut
the clippings one or more times are greatly enhanced.
Another object of the present invention is to provide a cutting system, as
above, that includes a plurality of baffles that position and temporarily retain the
clippings such that they are more likely to be recut by the cutting surfaces of a
rotary mower blade.
A further object of the present invention is to provide a cutting system for
a rotary lawn mower that will effectively mulch vegetation into very fine
particulate matter and spread it relatively randomly over the ground being
mowed.
Still another object of the present invention is to provide a cutting system
for a rotary lawn mower that includes a rotary blade having a plurality of cutters
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extending upwardly from the top surface of the blade, with the cutters cooperating
with a plurality of slotted baffles to recut vegetation clippings.
Yet another object of the present invention is to provide a cutting system
for a rotary lawn mower that includes a plurality of channels that direct clippillg~
into a baffle where the clippings are positioned to be recut by a blade.
In general, the present invention con,templates a cutting system for a rotary
lawn mower having a mower deck including a mower blade rotatably supported
substantially within the mower deck, cutters positioned along the mower blade,
and at least one baffle assembly carried b~y the mower deck and extending to a
position adjacent to but spaced from the cutters of the mower blade.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view of a rotary lawn mower blade arm and an
exemplary baffle assembly according to the concepts of the present invention.
Fig. 2 is a top plan view of a mower deck supporting the cutting system of
Fig. 1, with a portion of the deck top being broken away and portions of the
baffle assembly shown in plan and portions shown in section.
Fig. 3 is an end elevational view of the blade arm and baffle assembly
taken subst~nti~lly along the line 3-3 of Fig. 2.
Fig. 4 is a front elevational view of the blade arm and baffle assembly
taken substantially along the line 4-4 of Fig. 2.
Fig. 5 is a front elevational view of the blade arm taken substantially along
line 5-5 of Fig. 2.
Fig. 6 is an end elevational view sirnilar to Fig. 3 of a blade arm and an
alternative configuration for a baffle assembly according to the present invention.
Fig. 7 is a front elevational view similar to Fig. 4 of the blade arm and
baffle assembly depicted in Fig. 6.
Fig. 8 is a top plan view of a mower deck supporting a second alternative
configuration of a cutting system according to the present invention with a portion
of the deck top being broken away and portions of the cutting system shown in
plan and portions shown in section.
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Fig. 9 is a front elevational view of the blade arm and baffle assembly as
well as one of the channeling walls taken substantially along line 9-9 of Fig. 8.
Fig. 10 is a side view of a channeling wall taken substantially along line 10-
10 of Fig. 8.
PREFERRED EMBODIMENT FOR CARRYING OUT THE INVENT~ON
A cutting system according to the concepts of the present invention is
depicted as being installed in a typical rotary lawn mower deck, generally
indicated by the numeral 10 in Figs. 2 and 4. The lawn mower deck 10 has a
10 generally planar or downwardly slightly concave deck top 12 and a substantially
cylindrical sidewall 14 extending downward from the periphery of the deck top 12toward the ground for engagement with grass, leaves, or other vegetation to be
mowed (not shown). The mower deck 10 functions as the frame of the lawn
mower and provides support for a motor (not shown) that drives a mower blade
15 20.
The deck 10 also protects the user from the mower blade 20 by at least
partially enc~ing the mower blade 20 within the deck 10. By encasing the blade
20, the deck 10 creates a swirl chamber 22 bounded by the plane 24 in which the
blade 20 rotates as its lower axial limit, the deck top 12 as its upper axial limit,
20 and the sidewall 14 as its radially outer limit. When the mower is in use, the
rotation of the blade 20 causes air flow in the swirl chamber 22 that is generally
circular and in the direction of the rotation of the blade 20. Grass and leaf
clippings that have been cut by the blade 20 are typically caught in the air flow
and are held in the swirl chamber 22 until the clippings fall out of the swirl
25 chamber 22 back through the plane of the blade 24. While blade rotation in only
one direction is depicted herein, it is to be appreciated that the principles
described herein are equally applicable for either direction of rotation of blade
20.
The cutting system of the present invention includes a plurality of baffle
30 assemblies, generally indicated by the numeral 30, disposed above the rotary
mower blade 20. Each baffle assembly 30 is supported by the mower deck 10 and
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extends downward toward the mower blade 20. The mower blade 20 includes at
least two arms 32 that are supported by an input shaft 34 that transfers rotary
motion from a motor (not shown) to the mower blade 20 (Fig. 2). A primary
cutting surface 40 is formed in the front surface of each arm 32. Each cutting
5 surface 40 is configured to cut through vegetation and create a clipping.
Each arm 32 has a proximal portion 36 and a distal portion 38, the distal
portion 38 being the farthest from the shaft 34 while the proximal portion 36 isclosest to the shaft 34. Each distal portion 38 of each arm has a deflector 42
formed therein. The deflector 42 may be any one of various types that are known
10 in the art. In the embodiment of the invention depicted it he drawings, the
deflector 42 includes a tab 43 disposed angularly above the longitudinal axis 44of the blade 20. The tab 43 is curved upwardly toward the deck top 12 and
inwardly toward the shaft 34. The curve of the deflector 42 at least partially
creates an upward air flow when the mower blade 20 rotates which at least
15 partially creates a circular air flow in the swirl chamber 22. The upward airflow
helps direct clippings into the swirl chamb~ r 22.
A secondary cutting surface 46 is disposed directly behind each deflector
42 on each arm 32. The secondary cutting surface 46 is generally parallel to andis disposed in the same blade plane 24 as the primary cutting surface 40. The
20 secondary cutting surface 46 provides a second cutting chance at any vegetation
that avoids being cut by the primary cutting surface 40.
A plurality of cutters 48 extend fronn the top surface of the distal portion
38 of each blade arm 32 behind the primary cutting surface 40. Each cutter 48
has a forward facing cutting surface 52 that is configured to cut vegetation. Each
25 cutter 48 is configured to cooperate with a respective portion of baffle assembly
30 as will be further explained hereinafter. In the embodiment of the present
invention depicted in the drawings, three equal-sized, triangular cutters 48 aredisposed in substantially parallel relation on each blade arm 32. In other
embodiments of the present invention, the size of the cutters 48 may vary, and the
30 position of each cutter 48 with respect to the blade arm 32 may also vary.
Similarly, the overall shape of the cutters 48 need not be limited to the tri:lnFtll~r
.
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cutters 48 depicted in the drawings. Square or rounded cutters 48 may also
perform the function required by the present invention.
The plurality of baffle assemblies 30 are attached to the mower deck top
12 and extend downward toward the blade 20. In the embodiment of the
S invention depicted in the drawings, three baffle assemblies 30 are attached to the
deck 10 and are circumferentially substantially equiangularly distributed about the
deck 10. Preferably, the number of baffle assemblies 30 is in the range from 3
to 7 or more, and it has been found that five baffle assemblies 30 evenly
distributed every 72 degrees about the mower deck 10 is a preferred arrangement.10 However, even a single baffle assembly 30 configured and mounted according to the present invention yields substantially mulching benefits.
The longitudinal axis 50 of each baffle assembly 30 is angularly disposed
with respect to a radius 54 of the mower deck 10. As may be perhaps best seen
in Fig. 2, each baffle assembly 30 is disposed at an acute angle, indicated by the
numeral 56, with respect to a radius 54 passing through the inner end 58 of the
baffle assembly 30. Although each baffle assembly 30 may be mounted parallel
to a radius of the deck, it is preferred that the radially outer end of each baffle
assembly 30 be angularly offset in the direction of blade approach at an angle 56
in the range of approximately 10 to 30 degrees. The angled baffle assemblies 30
help prevent the cutting system from clogging particularly when the mower is used
to cut heavy, wet vegetation.
Each baffle assembly 30 includes a baffle 60 supported by a bracket,
generally indicated by the numeral 62. Each baffle 60 is configured to be spacedfrom but adjacent to or in close proximity to the blade 20 so that clippings held
by the baffle 60 may be recut by the blade 20 as it passes the baffle 60. The
bracket 62 may be supported from the deck top 12 by a plurality of nut and bolt
assemblies 64, as is depicted in the drawings. However, the present invention also
contemplates that the brackets 62 may be attached by other connectors. For
instance, the brackets 62 may be welded to the deck top 12. If desired, the decktop 12 may be contoured to facilitate placement and seating of brackets 62.
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Additionally, the brackets 62 may be supported in whole or in part by the sidewall
14 of the deck 10.
Each bracket 62 includes an attachment portion 70 connected to a
mounting portion 72. As may be seen in Fig. 3, the mounting portion 72 is tiltedforward in the direction of blade 20 rotation, such that the mounting portion 72and the ~tt~chment portion 70 form an acute angle, indicated by the numeral 74.
In other embo(liment~, the attachment portion 70 of the bracket 62 may be
reversed, such that the angle between the mounting portion 72 and the
attachment portion 70 is obtuse. In the preferred embodiment of the present
invention, the acute angle 74 between the mounting portion 72 and the
attachment portion is in the range of approximately 60 to 80 degrees. A third
portion 76 of bracket 62 extends from the lower edge of the mounting portion 72.The third portion 76 is also tilted forward in the direction of blade 20 rotation,
such that the third portion 76 forms an aculie angle, indicated by the numeral 78,
with the mounting portion 72 of the bracket 62. When assembled, the third
portion 76 is spaced from the baffle 60 anàl provides support when the blade 20
causes the baffle 60 to bend and contact the third portion 76.
A baffle 60 is attached to each bracket 62 by a suitable connector, such as
a plurality of nut and bolt assemblies 80 having flat, broad heads 82. The
configuration of the heads 82 provides support to the baffle 60 when the baffle
6û is subjected to bending forces. The baffle 60 may be a solid unitary member
fabricated from a variety of materials such as metal, rubber, or plastic. In this
respect, an elastomer, such as neoprene, with a single thin reinforcing layer
encapsulated therein constituting one example. In lieu of a solid piece, the baffle
60, as depicted in Figs. 1-4, may include a plurality of bristles 84, as depicted in
Figs. 6-7, which may preferably have an arcuate thickness on the order of one-half
inch. In this latter instance, a polycarbon material of the type used in utilitybrushes constitutes one example. When the baffle 60 is fabricated from a solid
piece, a slot 90 is formed in the baffle 60 that corresponds with the contour ofeach cutter 48 on the blade arm 32. The slots 90 allow the cutters 48 to pass
through the baffle 60 without contacting or a~t least deflecting the baffle 60 to any
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substantial extend. The slots also prevent the baffles 60 from being destroyed by
the blade. When a bristle-type baffle 84 is used, the slots 90 may be preformed
by removing sections of bristles or the blade 20 may be used to form the slots 90
as it rotates through the baffle 84.
Each slot 90 is configured to allow the cutter 48 to pass through the baffle
60 without substantially contacting the baffle 60. As may be perhaps best seen
in Fig. 4, the slots 90 are generally triangularly shaped to allow the angled,
triangular cutters 48 to pass therethrough. In other embodiments of the present
invention where the cutters 48 are configured differentially, or are perpendicularly
disposed to the blade axis 44, the configuration of the slots 90 would change toaccommodate the cutters 48.
The present invention operates in the following manner. When the mower
is operated, the blade 20 rotates at a relatively high rate of speed that is suitable
for cutting vegetation. ~s the primary cutting surface 40 contacts a piece of
vegetation such as a blade of grass or leaf, the vegetation is cut and the clipping
is thrown above the blade 20 toward the cutters 48. If the clipping contacts thecutters 48 solidly, the clipping is immediately recut. Not all clippings, however,
are recut by the cutters 48.
Both the whole clippings and the recut clippings are then trapped in the
swirl chamber 22 by the air flow. The air flow carries these clippings into a baffle
assembly 30 where the clippings are supported by a baffle 60 or 84. As they are
being supported, the blade 20 continues to rotate and drives the cutters 48 against
clippings that are lying over or projecting into the slots 90 in the baffle 60 or 84.
The cutters 48 recut these clippings into smaller pieces until the clippings aresmall enough to avoid the baffles 60 or 84 and fall down through the plane of the
blade 24 where they may be cut again. Similarly, the clippings that are held at
the edges of the baffles 60 or 84 that are adjacent to the blade 20 are also recut
by the primary cutting surfaces 40. The resulting recut clippings are small enough
to be reclaimed by the ground being mowed and are normally sufficiently
dispersed such as not to damage the existing vegetation.
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An alternative embodiment of a cul:ting system according to the concepts
of the present invention is depicted as being installed in a typical rotary lawnmower deck, generally indicated by the numeral 100 in Figs. 8-10. The lawn
mower deck 100 has a generally planar or downwardly slightly concave deck top
112 and a subst~nti~lly cylindrical sidewall 114 extending downward from the
periphery of the deck top 112 toward the ground for en~ement with grass,
leaves, or other vegetation to be mowed (not shown). The mower deck 100
functions as the frame of the lawn mower and provides support for a motor (not
shown) that drives a mower blade 120.
The deck 100 also protects the user from the mower blade 120 by at least
partially encasing the mower blade 120 within the deck 100. By encasing the
blade 120, the deck 100 creates an inner spindle grass compression swirl chamber122 bounded by the plane 124 in which th~e blade 120 rotates as its lower axial
limit, the deck top 112 as its upper axial limit, and the sidewall 114 as its radially
outer limit. When the mower is in use, the rotation of the blade 120 causes air
flow in the swirl chamber 122 that is generally circular and in the direction of the
rotation of the blade 120. Grass and leaf clippings that have been cut by the
blade 120 are typically caught in the air flow and are held in the swirl chamber122 until the clippings fall out of the swirl chamber 122 back through the plane124 of the blade 120. While blade rotation in only one direction is depicted
herein, it is to be appreciated that the principles described herein are equallyapplicable for either direction of rotation c,f the blade 120.
The cutting system of the alternative embodiment of the present invention
includes a plurality of baffle assemblies, generally indicated by the numeral 130,
disposed above the rotary mower blade 120. Each baffle assembly 130 is
supported by the mower deck 100 and extends downwardly toward the mower
blade 120. The mower blade 120 inclucles at least two arms 132 that are
supported by an input shaft 134 that transflers rotary motion from a motor (not
shown) to the mower blade 120. A primary cutting surface 140 is formed in the
front surface of each arm 132. Each cutting surface 140 is configured to cut
through vegetation and create a clipping.
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A plurality of cutters 148 extend upwardly from the top surface of the
outer portion of each blade arm 132 behind the primary cutting surface 140.
Each cutter 148 has a forward facing cutting surface 152 that is configured to cut
vegetation. Each cutter 148 is configured to cooperate with a respective portion5 of the baffle assembly 130, as will be further explained hereinafter. In the
embodiment of the present invention depicted in Figs. 8-10, three e~ual-sized
triangular cutters 148 are disposed in substantially parallel relation on each blade
arm 132. In other embodiments of the present invention, the size of the cutters
148 may vary, and the position of each cutter 148 with respect to the blade arm
132 may also vary. Similarly, the overall shape of the cutters 148 need not be
limited to the tri~ngul~r cutters 148 depicted in the drawings. Square or rounded
cutters 148 may also perform the function required by the present invention.
The plurality of baffle assemblies 130 are attached to the mower deck top
112 and extend downwardly toward the blade 120. In the embodiment of the
invention depicted in Figs. 8-10, four baffle assemblies 130 are attached to thedeck 100 and are circumferentially, substantially equiangularly distributed about
the deck 100. Preferably, the number of baffle assemblies 130 is in the range
from three to seven or more, and it has been found that four baffle assemblies
130 evenly distributed every 90 degrees about the mower deck 100 is a preferred
arrangement. However, even a single baffle assembly 130 configured and
mounted according to the present invention yields substantial mulching benefits.In the embodiment of the invention depicted in Figs. 8-10, each baffle assembly
130 is disposed subst~nti~lly parallel to a radius of the mower deck 100.
Each baffle assembly 130 includes a baffle 160 supported by a bracket,
generally indicated by the numeral 162. Each baffle 160 is configured to be
spaced from but adjacent to or in close proximity to the blade 120 so that
clippings held by the baffle 160 may be recut by the blade 120 as it passes the
baffle 160. The bracket 162 may be supported from the deck top 112 by a
plurality of nut and bolt assemblies 164, as is depicted in the drawings. However,
the present invention also contemplates that the brackets 162 may be attached byother connectors. For instance, the brackets 162 may be welded to the deck top
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112. If desired, the deck top 112 may be contoured to facilitate placement and
seating of the brackets 162. Additionally, lhe brackets 162 may be supported in
whole or in part by the sidewall 114 of the deck 100.
Each bracket 162 includes slotted portion 170 connected to a mounting
S portion 172. The mounting portion 172 is substantially flat and is configured to
abut the inner surface of the deck top 112. The slotted portion 170 eYtçn(lc
downwardly from the mounting portion 172 and is configured to slidingly receive
the upper end of the baffle 160. The baffle 160 is held by slotted portion 170
through the engagement of a pair of lips 174 extending inwardly from the bottom
of the slotted portion 170 with a rail 176 disposed at the top of the baffle 160.
The rail 176 and lips 174 are configured such that the rail 176 may slide withinthe slot 178 in the slotted portion 170 without falling through the bottom of the
slotted portion 170. The rail 176 may be :~ormed by clamping slotted length of
metal around a bar 180 about which individual bristles 184 are wrapped. When
the rail 176 is damped on the bristles 1~4 and bar 180, the bristles 184 are
subst~nti~lly retained by the rail 176 and cannot be removed without being
broken.
The manner in which the brackets 162 hold the baffles 160 allows the
baffles 160 to be quickly and easily changed without the step of unassembling a
nut and bolt combination. As may be perhaps best seen in Fig. 8, each slotted
portion 170 abuts the sidewall 114 of the deck 100 such that the baffles 160
cannot move radially outwardly out of the slotted portions 170. The sidewall 114cooperates with a pin 182 that is received through holes in the slotted portion 170
to hold the baffle 160 in the bracket 162. The pin 182 is removed when one
desires to remove the baffle 160 from the bracket 162. The baffle 160 is then slid
inwardly until free of the bracket 162. A new baffle 160 may then be inserted
and the pin 182 replaced.
The baffle 160 may be a solid, unitary member fabricated from a variety
of materials, such as metal, rubber, or plastic. In this respect, an elastomer, such
as neoprene, with a single thin reinforcing layer encapsulated therein, constitutes
one example. In lieu of a solid piece, the baffle 160, as depicted in Fig. 9, may
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12
include a plurality of bristles 184 that form a baffle 160 having a thickness on the
order of one-half inch. In this latter instance, a polycarbon material of the type
used in utility brushes constitutes one example. The baffles 160 are fabricated
such that each baffle 160 has a slot 190 that corresponds with a cutter 148. Theslots 190 allow the cutters 148 to pass through the baffle 160 without contacting
or at least deflecting the baffle 160 to any substantial extent. The slots 190 also
prevent the baffles 160 from being destroyed by the blade 120. When a bristle-
type baffle 160 is used, the slots 190 may be preformed by removing sections of
bristles, or the blade 120 may be used to form the slots 190 as it rotates through
10 the baffle 160.
As may be perhaps best seen in Fig. 8, a plurality of channeling walls 200
extend downwardly from deck top 112 to form tapered channels 202. Each
tapered channel 202 becomes narrower or tapers in the direction of blade
rotation, with only one direction being depicted for purposes of example. A
15 baffle assembly 130 is disposed at the narrow portion of each channel 202. The
tapered channels 202 function to direct the clippings contained in the swirl
chamber 122 into the baffle assemblies 130 where the clippings may be recut by
cutters 148.
Each channeling wall 200 is arcuate and has a first end 204 and a second
20 end 206. As may be perhaps best seen in Fig. 10, the first end 204 of each
channeling wall 200 is substantially shorter than the second end 206 of the
channeling wall 200. That is, first end 204 of channeling wall 200 does not extend
downwardly from deck top surface 112 as far as the second end 206 of a
channeling wall 200 extends downwardly. In the embodiment of the invention
25 disclosed in Figs. 8-10, the second end 206 of the channeling wall 200 extends
downwardly, such that it is substantially even with the lower ends of the bristles
184 and does not contact the blade 120. The height of the first end 204 is
indicated generally by the numeral 210 and is approximately one-third of the
height of the second end 206 which is generally indicated by the numeral 212. Of30 course, other configurations of the channeling walls 200 will also function with the
concepts of the present invention. For instance, the first end 204 of the
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channeling wall 200 may be substantially the same height as the second end 206
of the channeling wall 200. Further, the first end 204 may be substantially evenwith the interior surface of the deck top 112.
This alternative embodiment of the present invention operates in the
following manner. When the mower is operated, the blade 120 rotates at a
relatively high rate of speed that is suitable for cutting vegetation. As the primary
cutting surface 140 contacts a piece of vegetation, such as a blade of grass or leaf,
the vegetation is cut, and the clipping is thrown above the blade 120 toward thecutters 148. If the clipping contacts the cutters 148 solidly, the clipping is
immediately recut. Not all clippings, however, are recut by the cutters 148.
Both the whole clippings and the recut clippings are then trapped in the
inner spindle grass compression swirl chamber 122 by the air flow created by theblade rotation. The air flow carries these clippings into one of the tapered
channels 202 that directs the clippings into a baffle assembly 130 where the
clippings are supported by a baffle 160. As the clippings are supported against
the ba~le 160, the blade 120 continues to rotate and drives the cutters 148 against
the clippings that are Iying over or projecting into the slots 190 in the baffle 160.
The cutters 148 recut these clippings into smaller pieces until the clippings are
small enough to avoid the baffles 160 and fall down through the plane 124 of theblade 120 where they may be recut again. Similarly, the clippings that are held
at the edges of the bristles 184 that are adljacent to the blade 120 are also recut
by the primary cutting surfaces 140. Tble resulting recut clippings are small
enough to reclaimed by the ground being mowed and are normally sufficiently
dispersed such as not to damage the existing vegetation.
Thus, it should be evident that the cutting systems disclosed herein fulfill
the various objects of the present invention set forth above and otherwise
constitute an advantageous contribution to the art. As will be apparent to persons
skilled in the art, modifications can be madle to the preferred embodiments of the
present invention disclosed herein without departing from the spirit of the
invention. For instance, the cutting system disclosed herein may be used with
mower configurations having two, three, or more, blades that are disposed next
.
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14
to each other. Such mowers cut substantially wider swaths than mowers with a
single cutting blade, and it is just as desirable in these mowers to recut clippings
as in single-blade mowers. The scope of the invention is thus limited solely by the
scope of the attached claims.
