U.S. patent application number 10/075116 was filed with the patent office on 2002-09-12 for wheeled lawn care unit.
Invention is credited to Brazell, Kenneth M., Dils, Jeffrey M., Everts, Robert G., Vidal, Raul F..
Application Number | 20020124540 10/075116 |
Document ID | / |
Family ID | 24032332 |
Filed Date | 2002-09-12 |
United States Patent
Application |
20020124540 |
Kind Code |
A1 |
Everts, Robert G. ; et
al. |
September 12, 2002 |
Wheeled lawn care unit
Abstract
A compact, lightweight and easy-to-use wheeled lawn care unit
comprising a two-wheeled carriage, a power source, plurality of
tools which may be alternatively connected to the power source, a
handle and a boom connecting the selected tool to the power source.
The power source is pivotally connected to the carriage at a
location within its footprint. The unit has a low center of gravity
by placing the power source pivot and center of gravity within a
cylinder defined by the wheels. The boom extends horizontally from
the power source and is of a split boom configuration which allows
selective rotation for the boom portions relative to one another.
An edger that can be selected for the unit, which includes a
spring-loaded wheel. The edger may be rotated from a non-working
position where the edger blade does not contact the ground to a
working position by rocking a handle behind the carriage forward
against the bias of the spring. A second more compact version has
the shield positioned on the boom.
Inventors: |
Everts, Robert G.;
(Chandler, AZ) ; Dils, Jeffrey M.; (Chandler,
AZ) ; Brazell, Kenneth M.; (Phoenix, AZ) ;
Vidal, Raul F.; (Gilbert, AZ) |
Correspondence
Address: |
John E. Nemazi
Brooks & Kushman P.C.
22nd Floor
1000 Town Center
Southfield
MI
48075-1351
US
|
Family ID: |
24032332 |
Appl. No.: |
10/075116 |
Filed: |
February 12, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10075116 |
Feb 12, 2002 |
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09510820 |
Feb 23, 2000 |
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6345489 |
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Current U.S.
Class: |
56/12.7 |
Current CPC
Class: |
A01D 34/67 20130101;
A01D 34/824 20130101; A01B 51/02 20130101; A01D 42/04 20130101;
A01D 34/84 20130101; A01D 42/08 20130101; A01D 42/06 20130101 |
Class at
Publication: |
56/12.7 |
International
Class: |
A01D 034/84 |
Claims
What is claimed is:
1. A wheeled lawn care unit comprising: a wheeled carriage, a power
source pivotably connected to the carriage about a generally
vertical axis to allow selective rotation in a substantially
horizontal plane, a plurality of tools, each of which may be
alternatively selected to be joined to the power source so to be
the working tool for the unit, each tool joined to a tool boom
portion, a power source boom portion, which is rigidly joined to
the power source so to be maintained in a substantially horizontal
orientation and to move with the power source about the vertical
axis, and a connector allowing selective joinder of the power
source boom portion to a tool boom portion of a selected tool at
selective rotational angular relationships between the
portions.
2. The lawn care unit of claim 1, further comprising a locking
device for holding the power source at a selected transverse
angular relationship to the carriage.
3. The lawn care unit of claim 2, further comprising a single
control mechanism for the locking device and the connector where
the locking device and connector are jointly controlled by the
control mechanism.
4. The lawn care unit of claim 3, where the control includes a
support that spans the space between the connector and the carriage
and moves with the boom about the pivot and indicators on the
support and carriage that provide for alignment of the boom at
predetermined positions relative to the vertical axis.
5. The lawn care unit of claim 1, where the wheeled carriage has a
pair of wheels and the center of gravity of the unit lies within a
cylinder defined by the wheels.
6. A wheeled lawn care unit having a center of gravity for use on a
surface comprising: a power source having a footprint, a carriage
having a front end, a pair of wheels having a common wheel axis and
a substantially vertical pivot for power source positioned within
power source footprint, a tool positioned forwardly of the front
end of the carriage which turns with the power source on the pivot,
and a center of gravity of the unit within a cylinder defined by
the wheels and forwardly of the wheel axis.
7. The lawn care unit of claim 6, where the center of gravity lies
within two inches of the wheel axis.
8. The lawn care unit of claim 6, where the pivot lies within the
wheel cylinder.
9. A wheeled lawn care unit comprising: a carriage having a front
end, wheels and a substantially vertical pivot, a power source
having a circular footprint defined by the outer perimeter of the
power source when viewed from above, a tool positioned forwardly of
the front end of the carriage and joined to the power source, where
the tool turns on the axis which lies within the footprint of the
power source.
10. The lawn care unit of claim 9, further comprising a boom
connecting the tool to the power source and the tool, power source
and boom turn together on the pivot as a unit.
11. The lawn care unit of claim 9, further comprising a shield
which lies between the power source and the tool and overlies the
boom.
12. The lawn care unit of claim 11, where the shield is connected
to the boom and pivots therewith.
13. The lawn care unit of claim 9, where the power source has a
side profile and the wheels have a common side profile and a common
axis and the unit has a center of gravity that lies within the side
profiles of the power source and wheels forwardly of the wheel
axis.
14. A wheeled lawn care unit comprising: a carriage having a front
end, a back end and a pair of wheels with a common wheel axis, a
handle joined to the carriage and positioned rearwardly of the
carriage wheel axis, and an edger joined to the carriage and
positioned forwardly of the front end having an edging blade that
rotated in a substantially vertical plane and an edger wheel, the
edger wheel having a non-working position where the bottom of the
edger wheel and bottom of the carriage wheels define a
substantially horizontal planar surface that is below the blade and
a work position where the bottom of the edger wheel and bottom of
the carriage wheels define a substantially horizontal planar
surface through which the blade passes, the edger having a bias
that urges the wheel toward the non-working position, where by
rocking the handle forwardly, the edger bias is overcome and the
edger wheel moves from the non-working position to the work
position.
15. The lawn care unit of claim 12, further comprising an edger
shield and where the edger bias is provided by a spring joined to
the edger wheel and edger shield.
Description
TECHNICAL FIELD
[0001] This invention relates to a wheeled lawn care system adapted
to receive a variety of lawn tool attachments including a line
trimmer, a blower, an edger, a cultivator, a snow thrower, etc.
BACKGROUND ART
[0002] Home lawn care equipment takes a variety of forms which are
well known in the art. These include such tools as line trimmers,
blowers, edgers, cultivators, snow throwers and the like. Wheeled
units for individual tools are available and many of these systems
work efficiently and provide the desired result of cutting,
trimming, blower, etc. However, it is often inefficient to maintain
such a wide variety of tools. For hand-held devices, this problem
has been addressed by patents such as U.S. Pat. No. 5,802,724,
which discloses couplings for split-boom power tool with a wide
range of selective attachments. Attempts to develop inexpensive
wheeled units allowing for selective substitution of a wide range
of lawn tools has not been as successful. Units have been developed
but these are often difficult to use, provide for limited selection
of tools that may be attached and/or have other disadvantages that
prevent their wide adoption. Thus, it is desirable to develop a
system which is adaptable to selectively achieve all of these
results while remaining compact, lightweight and easy to use.
DISCLOSURE OF INVENTION
[0003] The present invention is a wheeled lawn care unit which
comprises a wheeled carriage with a power source pivotally
connected to the carriage about a generally vertical axis to allow
selective rotation in a substantially horizontal plane. The unit
includes a plurality of tools which may be alternatively selected
as the working tool. A tool boom portion of the selected tool is
connected for selective angular relationship to a boom portion
joined to the power source which is maintained in a substantially
horizontal orientation. The power source and tool turn on the pivot
axis and may be locked at a selected angular relationship to the
carriage.
[0004] The power source is positioned on the carriage so that the
unit's center of gravity is within a cylinder defined by the wheels
of the carriage and forward of the wheels' axis. The pivot axis of
the tool is positioned within the power source footprint and
preferably within the wheel cylinder also.
[0005] A tool that may be part of the unit is a wheeled edger
having an edging blade that is rotated in a substantially vertical
plane. The edger wheel has a non-working position where the bottom
of the edger wheel and bottom of the carriage wheels define a
substantially horizontal planar surface that is below the blade and
a work position where the bottom of the edger wheel and bottom of
the carriage wheels define a substantially horizontal plane to
which the blade passes. The edger has a bias that urges the wheel
towards the non-working position but which may be overcome to move
the wheel to its work position by rocking the handle forwardly.
[0006] Accordingly, it is an object of the present invention to
provide a wheel lawn care unit that allows for selection of a
working tool from a plurality of tools that may be used and for the
positioning of the tool at a variety of positions through selective
angular adjustments between boom portions and between the power
source and carriage.
[0007] Another object of the present invention is to provide a
wheeled lawn care unit with a low center of gravity and a pivot for
the power source which lies within its footprint.
[0008] Still another object of the present invention is to provide
a wheeled lawn care unit with an edger that may be rocked between a
working and non-working position.
[0009] These and other objects, features, and advantages of the
present invention are readily apparent from the following detailed
description of the best mode for carrying out the invention when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is a perspective view of an embodiment of the lawn
care unit of the present invention showing an edger attached.
[0011] FIG. 2 is an exploded view of the unit of FIG. 1.
[0012] FIG. 3 is a perspective view of a blower tool according to
the present invention.
[0013] FIG. 4 is a perspective view of a line trimmer according to
the present invention.
[0014] FIG. 5 is a perspective view of a sickle bar according to
the present invention.
[0015] FIG. 6 is a perspective view of a cultivator according to
the present invention.
[0016] FIG. 7 is a perspective view of a snow thrower according to
the present invention.
[0017] FIG. 8 is a perspective view of a dethatcher according to
the present invention FIG. 9 is a front view of the blower showing,
in phantom outline, the blower rotated about the boom axis.
[0018] FIG. 10 is a plan view of the embodiment of the present
invention of FIG. 1 including a line trimmer and, in phantom
outline, showing the line trimmer transversely angularly
displaced.
[0019] FIG. 11 is a side view of the embodiment the present
invention of FIG. 1 including the edger showing it in a working
position and, in phantom outline, in a non-working position.
[0020] FIG. 12 is a side view of the edger in the working position
and, in phantom outline, in the non-working position.
[0021] FIG. 13 is a side partially cut-away view of a portion of
the coupling of the embodiment of FIG. 1.
[0022] FIG. 14 is a partial front view of the shield, boom and
coupling of the embodiment of FIG. 1.
[0023] FIG. 15 is a bottom view of the carriage of the embodiment
of FIG. 1.
[0024] FIG. 16 is a perspective view of the embodiment of the lawn
care unit of the present invention showing a line trimmer
attached.
[0025] FIG. 17 is a side view of the embodiment of the present
invention of FIG. 16.
BEST MODE FOR CARRYING OUT THE INVENTION
[0026] Referring to FIGS. 1 and 2, the wheeled lawn care unit 10 is
shown according to the present invention. The lawn care unit has a
carriage 12, including body 14, and a pair of relatively large
wheels 16, 18. The wheels are attached to the body by stub axles 20
and have a substantially horizontal common axis 22. To protect the
wheels, side guards 23 extend from the side of the carriage
forwardly of the wheels. The carriage also has shield 24 placed
forwardly of recess 27 in body 14. The recess is for placement of
power source 28. The power source is allowed to selectively rotate
in a substantially horizontal plane about which has generally
vertical pivot axis 30 of the power source pivot 31. Forwardly from
the carriage is tool 32. The tool is connected to motor housing 34
by boom 36. Extending rearwardly and upwardly from the carriage is
handle 37 with appropriate control devices on the handle, in a
manner common to lawn mower and other lawn tools, to allow the
operator convenient control of the unit during operation.
[0027] Power source 28 provides the power to drive the unit's
tools, which will be described later. It may be in the form of a
gas-powered motor or an electric motor. In the preferred
embodiments, it is in the form of a four-cycle gas-powered motor.
Alternatively, it might be in the form of batteries for providing
power to electric motors in the individual tools.
[0028] As shown in FIG. 2, boom 36 includes motor portion 38 joined
to motor housing 34 and extending forwardly and substantially
horizontally from the housing. The boom also includes boom tool
portion 40 joined to the tool.
[0029] Boom connector 42 shown in FIGS. 2, 13 and. 15 joins two
boom portions while allowing them to be rotated relative to one
another about the longitudinal boom axis 43 of the boom motor
portion. Connector 42 includes a substantially cylindrical single
piece joint 44 having first and second ends 46 and 48. Joint 44 is
configured to form a compressible gap between flanges 49 that
extend from the joint. First tightening member is provided in
cooperation with the flanges for selectively decreasing the
cylindrical diameter of the joint at first end 46 of the joint
while squeezing the joint 44 against boom motor portion 38 to
rigidly secure the motor portion of the boom within the joint. In
this embodiment as shown in FIG. 2, first tightening member 50
includes a screw and nut (not shown) to squeeze the flanges
together. Second end 48 of the joint is designed for releasably
securing boom tool portion 40 within the connector. This is
achieved through second tightening member 54 which cooperates with
the flanges for selectively decreasing the cylindrically diameter
of the joint at second end 48 for squeezing the joint against boom
tool portion 40 to reasonably secure the boom tool portion within
the joint. The second tightening member takes the form of a bolt 56
and corresponding nut 57. Knob 58 is attached to the bolt for ease
of tightening and for positioning the boom transversely as will be
explained below.
[0030] Each tool boom portion further includes a resiliently biased
locating pin 60 which has been loaded outward by a biasing
mechanism. A chamfered lead edge portion 61 is formed along the
second end of the joint to facilitate insertion of the locating pin
into the joint so it may selectively located in aperture 62 in the
joint. Additional apertures are provided on the joint so that the
boom tool portion may be rotated within the joint around the axis
of the boom. The placement of the pin in an aperture also acts to
help maintain the boom tool portion in the connector prior to
tightening.
[0031] The power source is operably joined to the tool so to drive
the tool by power transmission device 64. Power transmission
devices are well known in the art, such as wiring for electrically
driven tools or a drive shaft in mechanically driven tools. The
transmission device extends through the boom. The preferred
embodiment takes mechanical power from motor 28 to the tool through
a transmission device in the form of drive shaft 64, which is shown
in FIG. 13.
[0032] Drive shaft 64 is divided into drive shaft motor portion 66
and drive shaft tool portion 68 corresponding to the respective
boom portions. Drive shaft portions are operably connected at the
boon connector by suitable power transmission connectors 70 at the
mating ends of the drive shaft portions. The motor thus provides
power to the drive shaft motor portion which is transmitted through
the power transmission connector then to the drive shaft tool
portion and in turn to the tool. The details of boom connector 42
and power transmission 64, which with alternatives, are disclosed
in U.S. Pat. No. 5,802,724, which is incorporated by reference.
[0033] Carriage shield 24 serves several purposes. As best shown in
FIGS. 10 and 11, it provides some protection to power source 28 and
to a lesser extent the operator from rearwardly thrown debris from
tool 32. Shield 24 also can provide for pull-string eyelet 74 when
using a motor with a forwardly positioned pull-string starter When
pull-string starter 76 is placed in a forward position on the
motor, it is desirable to have the string spaced from the motor
when pulled by the operator while holding handle 37. In the
preferred embodiment, this is achieved by threading pull string 78
of the starter through eyelet 74. This allows the operator to start
the motor while holding the handle with the string free of the
power source.
[0034] The unit also allows transverse movement of boom 36 to
angularly position the selected tool relative to pivot 30 as shown
in FIG. 10. Carriage body 14 extends above the boom and includes
transversely extending slot 72. The slot interacts with a boom
positioning device 55 to allow yet restrict transverse angular
movement of the boom with respect to pivot 30.
[0035] In this embodiment, as shown in FIG. 15, boom positioning
device 55 includes bolt 56 and knob 58 of connector 42. To maintain
and lock the boom in a desired angular relationship, knob 58 is
placed above the slot with bolt 56 extending through slot 72 into
joint 44 as described above. Suitable spacers, in the form of
washers 80, are placed around the bolt on each side of body 14 of
sufficient width to bridge slot 72. An additional spacer 81 may be
placed around the bolt above joint flange 49 for proper positioning
of connector 42 below body 14.
[0036] When knob 58 is tightened nut 57 is pulled toward the knob
by bolt 56. This both tightens the joint to hold the tool portion
of the boom in place and draws spacers 80 together against the
carriage body 14 to fix the boom in the desired transverse
position. When the knob is loosed the bolt can move within the slot
to allow for selection of the desired position. The width of the
slot defines the maximum amount of transverse movement allowed.
Angular displacement should be such as to allow the tool at its
extreme portions to extend beyond the wheels. The slot may allow as
much as 45.degree. of movement, although preferably the range is
30.degree..
[0037] To aid the operator in selecting the appropriate angular
relationship, indicators 82 shown in FIG. 2 may be placed on the
forward portion of shield 24 or body 14 suggestive proper tool
placement. These indicators may be placed on of sticker 82, with
written instructions such as "trimmer left position" or "trimmer
right position", symbols and/or angular descriptions.
Alternatively, the indicators may take the form of a series of
stays 84 or other physical restraints placed along either slot 72
and/or to aid proper angular placement.
[0038] By providing a control mechanism operated by knob 58 to
control both the longitudinal rotation of the boom elements and the
angular transverse relationship of the boom, efficiency and ease of
use is increased. It is envisioned however that on some
applications, separate controls for the transverse angular
relationship in the longitudinal rotational relationship may be
appropriate. Thus, for example, the connector may be placed
forwardly of the slot and a separate boom positioning device be
used to control the transverse angular positioning of the boom.
[0039] Carriage 12 is preferably of foam unibody construction. The
carriage includes a opening 85 below shield 24 and forwardly of
recess 26 shown in FIG. 14. The unibody construction allows for
ease of manufacture and assembly. Once motor housing 34 and boom
motor portion 38 are connected, they can as a unit be positioned in
carriage 12. The motor is positioned over the carriage with the
boom motor portion in opening 85. The motor is then lowered onto
pivot 30 with the boom motor portion moved upwardly against the
lower portion of carriage body 14 with boom positioning device 55
acting to prevent separation of the boom from the carriage.
[0040] By using a split boom and appropriate connector, the
operating tool on the wheeled lawn care unit may be easily changed
and positioned. Thus, numerous lawn care tools may be alternatively
attached, examples of which are shown in FIGS. 2-7. This include
edger 86, shown in FIG. 2; blower 88, shown in FIG. 3; line trimmer
90, shown in FIG. 4; sickle bar 92, shown in FIG. 5; cultivator 94,
shown in FIG. 6; snow thrower 95, shown in FIG. 7 and dethatcher
96, shown in FIG. 8. It is envisioned a wide range of lawn care
tools may be attached, of which these are examples. The specific
designs of the tools is generally well known in the art. Examples
of a blower, snow thrower and trimmer suitable for use with the
wheeled lawn care unit are disclosed in U.S. Pat. No. 5,768,749;
U.S. Pat. No. 5,603,173 and U.S. Pat. No. 5,802,724, both of which
are incorporated by reference.
[0041] As shown in FIG. 11, the motor portion of the boom extends
substantially horizontally forwardly from the power source, so to
allow the carriage and power source to maintain a low profile. To
position the tool in a proper working relationship, it would
normally be necessary to bend each boom tool portion 40 downwardly
with a bend appropriate for the given tool. Thus, most boom tool
portions will have a first substantially horizontal section 97
extending from boom connector 42 and a downward section 98 at the
tool, as shown in FIGS. 2 through 7. The use of a flexible drive
shaft allows this to be accomplished without special design of the
drive shaft for each application.
[0042] It may also be desired to extend the length of the boom so
that the tool is positioned at a further distant from the carriage.
In such a case as shown in FIG. 5, one or more extensions 99 may be
used, each including boom extension portion 100 enclosing a
corresponding drive shaft extension portion (not shown). Each
extension will be used with a boom connector 102, and have a power
transmission connector (not shown), corresponding to boom connector
42 and power transmission connector 70. Use of the extension allows
the tool to be used in a wider range of areas since it may be
difficult to wheel the unit into all portions of the work area.
While extensions may be curved for special purposes, it is
preferable that they are straight and maintained in a horizontal
position aligned with the boom motor portion so that the
longitudinal boon axis is maintained.
[0043] FIG. 9 shows how the tool can be rotated around the
longitudinal axis to provide use of the tool, in this case a
blower, with output in opposite directions. Blower 88 is positioned
to direct airflow to the right as shown by arrow 89 in FIG. 9 by
attaching the blower's boom tool portion 40 in boom connector 42 at
an appropriate position and tightening knob 58. If it is desired to
direct airflow in the opposite direction, it is simply a matter of
loosening knob 58 and rotating blower 88 to the new desired
position as shown in phantom outline in FIG. 9 providing air flow
to the left as represented by arrow 89'.
[0044] FIG. 10 is a top view of the wheeled lawn care unit showing
how the tool, in this case, a line trimmer 90 can be positioned at
different transverse angular relationships so to allow the line to
extend beyond either the left or right wheel. Pivot 30 for the tool
preferably lies within footprint 93 of the power source. Footprint
93 is defined by a circle enclosing the perimeter 91 of motor
housing 34 when viewed from above. This allows the lawn care unit,
particularly the carriage and wheels to have a narrow width so to
allow the unit to be moved to otherwise inaccessible areas.
[0045] To allow ease of movement and greater control of the unit,
it is desired that lawn care unit 10 be compact with a low center
of gravity CG. The center of gravity CG of the unit should be as
near as possible to carriage wheel axis 22 while remaining forward
of the wheel axis. The center of gravity CG should preferably not
be higher than the diameter D of the carriage wheel and no more
forward of the radius R of the wheel from wheel axis 22, as shown
in FIG. 11. Carriage wheels 16,18 share an effective axis 22
whether a single axle is used or a pair per each wheel. There is an
area extending between the wheels defining a wheel cylinder having
wheel axis 22 as its axis and an outer perimeter corresponding to
radius R of the wheels. The preferred location of the center of
gravity CG is within in the forward half of the wheel cylinder,
e.g., forward of a vertical plane passing through axis 22 and
between the wheels themselves. For greater ease of movement the
center of gravity should be no more than two inches from the wheel
axis. Placement of the center of gravity in this manner allows for
greater control of lawn care units by the operator. Due to the
close placement of the center of gravity to the wheel axis, when
the tool is removed from the lawn care unit, the effective center
of gravity of the remaining components of the unit will be shifted
rearwardly of the carriage wheel axis 22 to cause the remaining
components of the unit, unless constrained by the operator, to
rotate rearwardly so to rest on carriage wheels 16, 18 and handle
37. This has the benefit of allowing easy access to connector 42
during changing of tools.
[0046] To help ensure proper placement of the center of gravity, it
is preferred that the power source 28 be placed between to the
wheels in close proximity to wheel axis 22 since power source will
normally be a major contributor to the center of gravity. Placement
of pivot 30 within the wheel cylinder further aids in creating a
compact unit.
[0047] Although it is envisioned that many existing tools may be
adapted for use with the unit, edger 86 is particularly suited for
use with the wheeled lawn care unit. As shown in FIGS. 2, 11 and
12, edger 86 includes edger shield 104 and edger blade 106, which
is driven by in a manner known to the art, such as by gear box 107.
The edge blade will rotate in a substantially vertical plane.
Attached to the shield is wheel assembly 108. The wheel assembly
includes wheel bracket 110 and edger wheel 114, which is attached
to wheel bracket 110 by axle 116.
[0048] Extending upwardly along wheel bracket 110 is arcuate slot
120. A pin in the form of bolt 122 is joined to the back of edger
shield 104 and passes through slot 120 so to allow movement of the
wheel bracket on pin 122. A second pin in the form of bolt 124 is
joined to the upper end of bracket 110. Also joined to the second
pin by coiled compression spring 126, the other end of which is
fixed to the edger shield at third pin 128. Spring 126 acts to bias
the wheel assembly downward so that the wheel is normally extended
to a lowered non-cutting position. The edger wheel and carriage
wheels define a plane 129 corresponding to the surface upon which
they travel, such as a sidewalk, as shown in FIG. 11. When edger
wheel 114 is in the lower position 130, the trimmer blade to be
raised above the flat surface to a distance greater than the blade
radius thereby providing a clearance between the surface and blade.
This prevents contact of the blade and surface. When the blade is
properly positioned above the area to be edged, the operator can
then by pushing or rocking the handle forward pivot the lawn care
unit on the carriage wheels. This which will create a force on the
edger wheel so to overcome the spring strength. The wheel assembly
then moves along the slot to raise the edger wheel to a raised work
position 132 and effectively lowers the edger into a work position,
with the blade below plane 129 defined by the edger wheel and the
carriage wheels.
[0049] A second embodiment of the lawn care unit is shown in FIGS.
16-18. Many of the elements of this embodiment correspond to those
of the first embodiment shown in FIG. 1. The lawn care unit 210 has
a carriage 212, including body 214, and a pair of relatively large
wheels 216, 218. The wheels have a substantially horizontal axis
222. Handle 237 extends upwardly and rearwardly from the carriage
body. The second embodiment places boom 236 entirely above carriage
body 214. Shield 238 is moved rearwardly to abut the housing 234 of
power source 228. Shield 238 is attached to boom 236 rather than to
carriage body 214. Boom 236, power source 228, shield 238 and tool
232 share common pivot axis on carriage body 214 beneath the power
source housing 234. This allows for use of a smaller shield since
shield 238 will always be maintained between the power source and
the tool. In FIG. 16, tool 232 takes the form of line trimmer 290.
Other tools can be interchanged by use of connector 242. For
example, edger 286 is shown as the operating tool in FIG. 17.
[0050] Placement of shield 238 next to the power source allows for
connector 242 to be positioned slightly forwardly of the shield yet
still in cooperation with carriage body 214. Positioning support
281 spans the space between connector 242 and the carriage body 214
to support the boom, to aid in controlling of the angular
displacement of the boom and to provide a surface for a tool
angular displacement indicator 284, which in this embodiment takes
the form of a pointer or arrow. Knob 258 controls the tightening of
joint 244 around the boom tool portion. Knob 258 is also part of
boom positioning device 255 for transverse control of boom 236
along slot 272.
[0051] With knob 258 loosened, the selected tool boom tool portion
244 is positioned within connector 242 and held in a position
determined by placement of locating pin 260 in a selected aperture
262. The tool may be then transversely located for use of
indicators 282 on carrier body 214 with indicia at predetermined
locations suggesting optimal angular positions. A pointer 284 is
positioned on support 281 to aid the operator in correctly
positioning the tool. With knob 258 remaining untightened, the tool
is rotated on pivot 230 until pointer 284 is positioned above the
desired indicia 282. Knob 258 is then turned so to tighten bolt 257
causing support 281 and washer 280 to be pressed together against
carriage body 214 so to hold boom 236 at the desired angular
position. Tightening also causes joint flange portions 249 to be
drawn together capturing the boom tool portion 240 within joint
244. The boom motor portion 238 is joined to connector 242 by a
first tightening member 250 which draws the flanges 249 together
over the boom motor portion.
[0052] In this embodiment also the pivot for the tool also lies
under the power source 228 withing the footprint of power source
housing. Placement of shield 238 closer to power source 228 adds to
the compactness of the unit. The center of gravity CG of the unit
in this embodiment again lies just forward of wheel axis 222 and
within the wheel cylinder.
[0053] While embodiments of the invention have been illustrated and
described, it is not intended that these embodiments illustrate and
describe all possible forms of the invention. Rather, the words
used in the specification are words of description rather than
limitation, and it is understood that various changes may be made
without departing from the spirit and scope of the invention.
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