Note: Descriptions are shown in the official language in which they were submitted.
CA 02362611 2001-11-02
MANEUVERABLE AND ADJUSTABLE
LAWN MOWER HAVING AN EDGING-TRIMMING UNIT
FIELD OF THE INVENTION
The present invention relates to the general field of lawn mowers and is
particularly
concerned with a maneuverable and adjustable lawn mower having an edging unit.
BACKGROUND OF THE INVENTION
Lawn maintenance typically involves cutting of grass at regular time
intervals. The most
widely used implement for performing such function is the conventional
gasoline or
electric engine powered rotary lawn mower.
Although the lawn mower is particularly well suited for cutting relatively
large areas of
grass, it is often unable to adequately cut grass particularly around
plantings, flowers,
edges, raised obstructions and the like.
Separate machines are sold for accomplishing such edging and trimming
purposes,
and they usually include a cutting head having a cutting flail extending
therefrom. The
cutting head is typically supported on the end of the long handle that can be
oriented
horizontally for trimming or vertically for edging during use.
Thus, once the lawn is cut with the lawn mower, it is necessary to obtain and
use
another tool for the final trimming of the lawn. This entails additional costs
and requires
additional maintenance for the purchasing and care of a separate implement.
Furthermore, the use of two separate pieces of equipment increases the overall
time
required for performing a given task.
Accordingly, the prior art has shown some attempts at designing a combined
lawn
mower and trimmer thereby allowing the intended operator to trim the lawn
without the
necessity of obtaining a separate tool located remotely from the lawn mower.
However,
the prior art attempts have provided generally complex structures requiring
substantial
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CA 02362611 2001-11-02
or otherwise undesirable modification to the mower in order to receive the
attachment.
The prior art attempts have produced structures having undesirable features
which the
present disclosure seeks to improve.
Another common problem related to conventional grass lawn mowers relates to
their
lack of maneuverability at least in part related to the configuration of the
supporting
wheels. This lack of maneuverability provides for an unergonomical handling of
the
lawn mower leading to frustration and potential injuries to the intended user.
Still further, another common drawback associated with conventional lawn
mowers
relates to the type of connection between the lawn handle and the lawn mower
frame
which also deters the overall ergonomic aspects of the lawn mower.
Accordingly, there exists a need for an improved maneuverable and adjustable
lawn
mower having an edging unit.
Advantages of the present invention include that the proposed lawn mower has a
built-
in edging unit that can be either directly built onto new models or retro-
fitted to
conventional models without requiring substantial modifications thereto. The
edging unit
is of a simple construction so as to provide a unit that will be economically
feasible, long
lasting and relatively trouble free in operation.
Furthermore, the proposed lawn mower is provided with a three wheel support
configuration using a caster-type wheel having a specifically designed height
adjustment mechanism. The height adjustment mechanism of the caster-type wheel
allows for ergonomical and easy customization of the relative position between
the
supporting wheel and the lawn mower frame.
Still further, the proposed lawn mower is provided with a lawn mower handle
being
pivotable about two distinct and substantially orthogonal rotational axis. The
lawn
mower handle pivotal axis is provided with a releasable locking mechanism for
allowing
releasable locking thereof in a set of predetermined relative positions
relative to the
lawn mower frame.
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CA 02362611 2001-11-02
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will now be disclosed, by way of
example, in
reference to the following drawings in which
FIGURE 1 : In a perspective view, illustrates a maneuverable and adjustable
lawn
mower having an edging unit in accordance with an embodiment of the present
invention.
FIGURE 2 : In a partial top view with sections taken out, illustrates part of
the body of
the lawn mower shown in Figure 1.
FIGURE 3 : In a partial side elevational view with sections taken out,
illustrates part of
the lawn mower shown in Figure 1 with its handle in a storage configuration.
FIGURE 4 : In a schematic partial top view with sections taken out,
illustrates part of the
handle unit of the lawn mower shown in Figure 1 with its handle in an
operational
configuration.
FIGURE 5 : In a schematic partial top view with sections taken out,
illustrates part of the
handle unit of the lawn mower shown in Figure 1 with its handle in plier
pivoted
configurations, some of which being shown in phantom lines.
FIGURE 6 : fn a partial elevational view with sections taken out, illustrates
part of the
height adjustment mechanism of the lawn mower shown in Figure 1.
FIGURE 7 : In a partial elevational view with sections taken out, illustrates
the
mechanism shown in Figure 6 with its locking component being lifted away from
the
locking base.
FIGURE 8 : In a partial elevational view with sections taken out, illustrates
the
components shown in Figures 6 and 7 with the locking component being pivoted
relative to the locking base and the adjustment knob being rotated so as to
decrease
the height of the front section of the lawn mower.
FIGURE 9 : In a partial elevational view with sections taken out, illustrates
the
component shown in Figures 6 through 8 with the locking component being biased
back
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towards the locking base and the adjustment knob rotated so as to increase the
height
of the front section of the lawn mower.
FIGURE 10 : In a partial detailed view with sections taken out, illustrates
part of the
drive mechanism used for driving the edging unit, the drive mechanism being
shown in
an non operational configuration.
FIGURE 11 : In a partial detailed view with sections taken out, illustrates
part of the
drive mechanism used for driving the edging unit, the drive mechanism being
shown in
an operational configuration.
FIGURE 12 : In a partial side view with sections taken out, illustrates part
of the locking
mechanism for locking the lawn mower handle in a predetermined position. The
locking
mechanism being shown in the storage position.
FIGURE 13 : In a partial side view with sections taken out, illustrates part
of the locking
mechanism for locking the lawn mower handle in a predetermined position. The
locking
mechanism being shown in the operational configuration.
FIGURE 14 : In a partial top view with sections taken out, illustrates the
locking
mechanism shown in Figures 12 and 13.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring to Figure 1, there is shown a maneuverable and adjustable three
wheeled
lawn mower 10 in accordance with an embodiment of the present invention. The
lawn
mower 10 is typically of the walk-behind type and is provided with a frame 12
supporting a rotary engine 14. The rotary engine 14 is shown as being of a
fuel driven
type including a fuel compartment 16 but could be of the electrical or other
power
source type without departing from the scope of the present invention.
As shown in Figure 3, the engine 14 is mounted on the deck of the frame 12 and
drives
a main engine shaft 18 to which a set of main mower blades 20 are attached.
The
frame 12 includes a downwardly extending skirt 22 for protectively partially
enclosing
the blades 20 as is well known in the art.
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CA 02362611 2001-11-02
The lawn mower 10 is preferably of the three wheeled type including a pair of
rear
wheels 24 rotatably attached to a rear section of the frame 12 and a front
caster-type
wheel 26 rotatably attached to a caster-type wheel attachment bracket 28.
A conventional mechanism including a lever 30 for adjusting the relative
height between
the frame 12 and the rear wheels 24 is also provided. The relative height
between the
frame 12 and the caster-type front wheel 26 is preferably adjusted using a
front wheel-
to-frame height adjustment mechanism 32, illustrated in greater details in
Figures 6
through 9.
The lawn mower 10 is typically further provided with a rear wheel driving
assembly
including a rear wheel driving pulley 194 attached to the engine shaft 18 and
a rear
wheel driving belt 196 mechanically coupling the rear wheel driving pulley 194
and a
driving structure attached to the rear wheel axles 198.
One of the main features of the present invention resides in the presence of
an edging
unit 34 attached to the frame 12 and provided with an actuating lever 36 for
selectively
actuating the driving components of the edging unit 34. The lawn mower 10 is
further
provided with a lawn mower handle component 38.
Another main feature of the present invention resides in the pivotal
connection between
the handle component 38 and the frame 12, allowing for relative movement
therebetween, as shown in Figures 4 and 5 that will be hereinafter disclosed
in greater
details.
The engine 14 is typically provided with conventional external components such
as a
starter rope 40, having a conventional starter handle 42 and a throttle cable
44, having
a conventional throttle fever 46. Other relative standard components such as a
circuit
breaker pivotal rod 48 and the like is also further provided. it should be
understood that
various other items could be added and that modifications to the herein above
disclosed items could be made without departing from the scope of the present
invention.
The edging unit 34 includes : a conventional flail member filament 50,
attached in a
conventional manner to a driven flail head 52. The flail head 52 is solidly
attached to the
frame 12 using a flail head mounting bracket typically including a pair of
flail head
CA 02362611 2001-11-02
mounting legs 54. Alternatively, the flail head 52 could be pivotally attached
to the
frame 12 so as to allow the flail head 52 to pivot so that the flail member
filament 50
may be rotated between a vertical and a horizontal cutting plane.
Another main feature of the present invention resides in the presence of a
guiding
wheel 56, rotatably mounted on a guiding wheel shaft 58 also attached to the
flail
mounting legs 54. The guiding wheel 56 has a peripheral surface adapted to
rollably
abut against guiding surfaces such as edge walls, fences or the like 2T0.
Alternatively,
the guiding wheel 56 could be provided with size adjustment wheels or may be
provided
with relative positioning means so as to allow customization of the relative
position
thereof relative to the frame 12 so as to customize its abutment function to
different
types of environments.
The skirt 22 is provided with a skirt edging unit section 60 extending
integrally
therefrom. The skirt edging unit section 60 is configured, sized and
positioned so as to
at least partially enclose the mounting legs 54 while allowing at least a
section of the
guiding wheel 56 and of the flail member 50 to protrude therefrom. The skirt
edging unit
section 60 typically protrudes sidewardly and frontwardly from the
conventional
peripheral edge of the skirt 22 protectively enclosing the cutting blades 20.
As shown in
greater details in Figure 2, the skirt edging unit section 60 is provided with
an inwardly
bent cutting segment 62 defining a sharp cutting edge 64. The sharp cutting
edge 64 is
positioned so as to contact the distal end of the flail member 50 when the
latter reaches
a predetermined length so as to inherently maintain the flail member 50 at a
predetermined customized length.
The flail member head 52 is mechanically coupled to the conventional driving
cable 68
rotatably inserted within a conventional driving cable sleeve 66. The driving
cable 68
and associated driving cable sleeve 66 typically form an arch from the flail
member
head 52 towards a rearward section of the lawn mower 10.
As illustrated more specifically in Figures 10 and 11, the driving cable 68 is
mechanically coupled to an edging unit driving shaft 70 extending from an
edging unit
driven pulley 72. The edging unit driven pulley 72 is pivotally attached to a
base
segment 74 of the skirt 22 using a driven pulley attachment unit 76.
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The driven pulley attachment unit 76 includes a first attachment bracket 78
attached to
the base wall 74 and a second attachment bracket 80 pivotally attached to the
first
attachment bracket 78 by a hinge component 82 and also attached to a mounting
hub
84 around which the driven pulley 72 rotates. The first attachment bracket 78
is
preferably attached to the base wall 74 using conventional fastening means
such as
bolt 86 and nut 88 arrangements extending through a position adjustment slot
90
formed in the base wall 74 and allowing relative position adjustment between
the first
attachment bracket 78 and the base wall 74.
The shaft 70, the hub 84 and the associated driven pulley 72 are adapted to be
pivoted
relative to the base wall 74 about the pivotal axis created by the hinge
component 82 as
indicated by arrow 100 in Figure 11. A clutch cable 94 extending through a
clutch cable
sleeve 96 is attached to the shaft 70 using an attachment collar 98. The
clutch cable 94
is adapted to be pulled as indicated by arrow 100 by the pivotal movement of
the clutch
lever 36.
An edging unit driving belt 102 is wound around the driven pulley 72. As shown
more
specifically in Figures 2 and 3, the edging unit driving belt 102 is also
wound about an
edging unit driving pulley 104, mechanically coupled to the engine driving
shaft 18.
When the driven pulley 72 is in the inoperative position shown in Figure 10;
the edging
unit driving belt 102 rotates freely therearound without causing rotation of
the driving
shaft 70 and associated driving cable 78. When the actuating lever 36 is
pivoted so that
the clutch cable 94 pulls the driven pulley 72 in the operative position,
shown in Figure
11, the edging unit driving belt 102 becomes taught so that rotation of the
edging unit
driving pulley 104 is mechanically transmitted to the driven pulley 72 and to
the driving
cable 68. In turn, the driving cable 68 causes rotation of the flail member
head 52 and
the corresponding flail member 50 attached thereto. Optionally, a biasing
means could
be used to ensure the pivotal movement of the driven pulley 72 towards the
inoperative
position shown in Figure 10 when the clutch lever 36 is pivoted back to its
original
position.
Preferably, a set of guarding walls 106 extend from the base wall 74 adjacent
the driven
pulley 72 so as to form a partial enclosure for preventing potential contact
with the
rotating components. The protective walls 106 are preferably releasably
mounted to the
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CA 02362611 2001-11-02
base wall 74 by conventional fastening means such as bolts 108 so as to allow
access
to the protected components for maintenance, repairs or the like.
Referring now more specifically to Figures 6 through 9, there is shown in
greater details
the height adjustment means for adjusting the relative height between the
caster-type
wheel 26 and the frame 12. The caster-type wheel mounting bracket 28 is
pivotally
attached to a caster wheel base plate 110 by a set of conventional roller
bearing type
components 112. A caster-type wheel mounting bracket 122 preferably having a
generally "L" shaped configuration is attached to the frame 12 with its
shorter leg
attached to the frame 12 and its longer leg extending frontwardly therefrom.
An adjustment stem 114 extends upwardly from the base plate 110. The
adjustment
stem 114, defines a stem threaded segment 116 positioned proximal to the base
plate
110 and a stem attachment segment 118 positioned distally relative to the base
plate
110.
A first locking disc 120 is threatably mounted on the stem threaded segment
116 by an
internal threaded collar 124. The first locking disc 120 is provided with a
set of locking
recesses 126 formed on its upper peripheral edge 128. A second locking disc
130 is
solidly attached to the stem attachment segment 118 by an attachment screw 132
or
any other suitable means. The second locking disc 130 is provided with a set
of
protruding teeth 134 extending integrally from its lower peripheral edge 136.
The teeth
134 are configured, sized and positioned so as to be insertable within the
locking
recesses 126 of the first locking disc 120 so as to selectively prevent
relative rotation
therebetween.
The second locking disc 130 is stidably mounted on a knob spacing segment 140
extending integrally from a knob component 138. A biasing means for biasing
the
second locking disc 130 away from the knob component 138 is further provided.
The
biasing means preferably takes the form of a helicoidal-type spring 142
compressively
positioned between the lower face of the knob component 138 and the upper face
of
the second tocking disc 130.
In order to adjust the relative height between the caster-type wheel 26 and
the frame
12, the intended user merely needs to use his/her finger to grasp the grasping
legs 144
and lift the second locking disc 130 away from the first locking disc 120 as
indicated by
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CA 02362611 2001-11-02
arrows 146. The second locking disc 130 is lifted away from the first locking
disc 120
until the locking teeth 134 disengage the locking recesses 126 as shown in
Figure 7.
As shown in Figure 8, the knob 138 is then rotated according to arrow 148
causing
simultaneous rotational movement of the second locking disc 130 attached
thereto
through the locking screw 132.
The longitudinal channel 150 formed in the spacing segment 140 allows for
vertical
displacement of the second locking disc 130 as the threaded segment 116 causes
relative vertical displacement between caster-type wheel mounting bracket 122
and the
base plate 110 in both vertical directions as shown by arrows 152. When the
desired
relative height is reached between the caster-type wheel 26 and the frame 12,
the
grasping legs 144 are released and the locking teeth 134 inserted within
corresponding
locking recesses 126 to prevent relative rotational displacement between the
first 120
and second 130 locking discs.
Another main feature of the present invention resides in the configuration of
the pivotal
connection 154 between the handle 38 and the lawn mower frame 12. The pivotal
connection 154, as shown in Figures 4 and 5, allows the handle stem 156 to
pivot
simultaneously in two different geometrical planes relative to the handle
pivot axis 158.
A handle pivot sleeve 160 allows pivotal movement of the handle stem 156
according to
arrow 162 in a geometrical plane substantially perpendicular to the axis 158
while also
allowing pivotal movement of the handle stem 158 in a generally perpendicular
geometrical plane as indicated by arrows 164. The pivotal movement in the
perpendicular axis indicated by arrows 164 is at least partially restricted by
a stopper
bracket 166 extending from the pivotal sleeve 160 and having an abutment leg
thereof
adapted to abut against the pivotal axis 158 as shown in Figure 5.
Yet another main feature of the present invention resides in a locking means
for
releasably locking the handle 38 in a predetermined storage configuration. The
locking
means 168 shown schematically in Figures 4 and 5 is illustrated in ,greater
details in
Figures 12 through 14. A rear wheel adjustment brace 170 extends from the base
wall
74 in a conventional manner. A locking plate 172 is solidly attached to the
brace 170
using weld-lines or any other suitable means. The locking plate 172 is
provided with a
pair of locking notches 174, 178 formed on its preferably arcuate peripheral
edge 178.
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CA 02362611 2001-11-02
The handle pivotal axis 158 includes a pivotal rod 180 rotatably mounted about
a pair of
rod pivotal mounting pins 182 - only one of which is shown in Figure 14 -
extending
through both the brace 170 and the locking bracket 172. The pivotal rod 180 is
adapted
to rotate freely about the mounting pins 182 attached to the brace 170.
A locking handle 184 extends radially from the outer surface of the pivotal
rod 180. The
locking handle 184 is provided with a locking pin 186 slidably mounted
thereonto. The
locking pin 186 is preferably mounted on a locking pin mounting bracket 188
having a
guiding pin 190 slidiingly guided through a guiding slot 192 formed in the
locking handle
184.
A biasing means for biasing the locking pin towards its retracted position
shown in
Figure 14 is further provided. The biasing means preferably takes the form of
a
helicoidal-type spring 194 attached at a first end thereof to the pivotal rod
180 and at a
second longitudinal edge thereof to a spring attachment leg 196 extending from
the
mounting bracket 188. The mounting bracket 188 further defines a grasping peg
192 for
allowing the fingers of an intended user to slide the mounting bracket 188 and
associated locking pin 186 within the guiding slot 192.
The locking pin 186 is adapted to be releasably inserted within the locking
notches 174,
176 for selectively locking the handle stem 156 in either its storage position
shown in
Figures 3 and 12 or in its operational configuration shown in Figures 1, 4, 5,
and 13.
The helicoidal-type spring 194 is adapted to prevent unwanted release of the
locking
pin 186 form the locking notches 174, 176 as is well known in the art.
