U.S. patent application number 11/268709 was filed with the patent office on 2006-04-06 for simple, durable and easy-to-use earthworking machine.
This patent application is currently assigned to Turfco Manufacturing, Inc.. Invention is credited to Terrence R. Bondeson, Andrew Hawkins, Thomas E. Isaman.
Application Number | 20060070747 11/268709 |
Document ID | / |
Family ID | 25528867 |
Filed Date | 2006-04-06 |
United States Patent
Application |
20060070747 |
Kind Code |
A1 |
Isaman; Thomas E. ; et
al. |
April 6, 2006 |
Simple, durable and easy-to-use earthworking machine
Abstract
A sod cutter (10) is disclosed including a frame (12) formed by
welding the free edges of mount, frame and end plates (46a, 46b
46c) bent relative to one of two side plates (46) to the
corresponding edges of the other side plate (48). An axle assembly
(160) is pivotal relative to the frame (12) by a depth adjustment
lever (198) between a working position where wheels (16) carried by
the axle assembly (160) engage tubular members (168) slideably and
nonrotatably received on a drive shaft (166) and a transport
position where the wheels (16) are spaced from the tubular members
(168). A U-shaped handlebar (210) is positionable between an
operating position for grasping during operation and a storage
position for lifting and handling. A U-shaped control (212) is
pivotably mounted in front of and above the U-shaped handlebar
(210) for actuating the throttle of the engine (18). A threaded
lock (192) provides a connection between the handle mounting tube
(180) and the mast (214) of the handlebar (210) and is not
threadably removable by a spring pin (196) extending from the lock
(192) and received in a gap defined between the mounting tube (180)
and a locking plate.
Inventors: |
Isaman; Thomas E.; (Ham
Lake, MN) ; Bondeson; Terrence R.; (Woodbury, MN)
; Hawkins; Andrew; (Hopkins, MN) |
Correspondence
Address: |
NIKOLAI & MERSEREAU, P.A.
900 SECOND AVENUE SOUTH
SUITE 820
MINNEAPOLIS
MN
55402
US
|
Assignee: |
Turfco Manufacturing, Inc.
Minneapolis
MN
|
Family ID: |
25528867 |
Appl. No.: |
11/268709 |
Filed: |
November 7, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09982126 |
Oct 17, 2001 |
6962209 |
|
|
11268709 |
Nov 7, 2005 |
|
|
|
Current U.S.
Class: |
172/19 |
Current CPC
Class: |
Y10T 403/32508 20150115;
A01B 51/02 20130101; A01G 20/12 20180201; Y10T 74/20798
20150115 |
Class at
Publication: |
172/019 |
International
Class: |
A01B 45/04 20060101
A01B045/04 |
Claims
1-18. (canceled)
19. Method for forming a frame comprising: obtaining first and
second planar elements each having an opening therein; bending a
frame plate generally perpendicular to one of the first and second
planar elements, with the frame plate having a free edge; bending
an end plate generally perpendicular to one of the first and second
planar elements, with the end plate having a free edge; aligning
the openings of the first and second planar elements; welding the
free edge of the bent frame plate to the other of the first and
second planar elements while the openings are aligned; and welding
the free edge of the bent end plate to the other of the first and
second planar elements while the openings are aligned.
20. The method of claim 19 with the frame plate having a rear edge
and the end plate having a top edge, with the method further
comprising welding the rear edge to the top edge while the openings
are aligned
21. The method of claim 20 with bending the frame plate comprising
bending the frame plate generally perpendicular to the first planar
element, and with bending the end plate comprising bending the end
plate generally perpendicular to the first planar element.
22-25. (canceled)
26. Assembly for an earthworking machine comprising, in
combination: a handlebar having a mast secured thereto; a handlebar
mount, with the mast of the handlebar being removably and slideably
connected to the handlebar mount, with the handlebar being
positionable in a working position and in a storage position by
slideably removing the mast while secured to the handlebar from the
handlebar mount, then changing an orientation of the handlebar with
the mast secured thereto relative to the handlebar mount, and then
slideably connecting the mast while secured to the handlebar with
the handlebar mount, with the handlebar in the working position
being positioned for gripping by an operator while operating the
earthworking machine, and with the mast in the storage position
being positioned over the earthworking machine for lifting and
hauling.
27. The assembly of claim 26 with the handlebar being generally
U-shaped and including first and second legs extending from
opposite sides of a center, with the mast extending from the
center, with the first and second legs extending generally
horizontally rearward and the center extending generally
horizontally in the working position, with the first and second
legs extending forward and on opposite sides of the earthworking
machine in the storage position.
28. The assembly of claim 27 with the mast including a first linear
portion having a lower end and an upper end, with the center being
spaced from the upper end and extending generally perpendicular to
the first linear portion, with the first linear portion being
removably connected to the handlebar mount by being slideably
connected generally vertically to the handlebar mount in the
working position, with the first linear portion being removably
connected to the handlebar mount by being slideably connected at an
acute angle to vertical to the handlebar mount in the storage
position.
29. The assembly of claim 28 with the mast including a second
linear portion extending from the center of the handlebar at an
obtuse angle relative to the first and second legs of the handlebar
and extending from the first linear portion at an obtuse angle.
30. The assembly of claim 29 with the handlebar mount being a first
tube having an inner periphery and an outer periphery; a first
aperture formed in the first tube between the inner and outer
peripheries, with the first linear portion having an outer
periphery of a size for slideable receipt in the inner periphery of
the first tube; a bore formed in the first linear portion aligned
with the opening in the first tube when the first linear tube is
slideably received in the first tube; a lock plate held relative to
the outer periphery of the first tube to define a gap therebetween;
a second aperture formed in the lock plate; a threaded lock
extending through the first and second openings, with the threaded
lock being theadably received in one of the first tube and the lock
plate; and a pin located in the gap and extending radially from the
lock, with the pin preventing the lock from being threaded out of
the said one of the first tube and the lock plate, with the lock
being insertable into the bore to prevent sliding of the first
linear portion relative to the fist tube and being removable from
the bore to allow sliding of the first linear portion relative to
the first tube.
31. (canceled)
Description
BACKGROUND
[0001] The present invention relates generally to earthworking
machines, particularly to earthworking machines involving an
oscillatory blade movement, such as sod cutters, edging machines
and pipe laying machines, and specifically to earthworking machines
which are simple, durable and easy-to-use.
[0002] Sod cutters and other oscillatory blade earthworking
machines have been rather widely employed. One example of a sod
cutter which has enjoyed commercial success is shown in U.S. Pat.
No. 5,009,270. Traditional sod cutters were of complicated design,
providing multiple adjustments, and were largely directed to
commercial applications because of their costs and difficulty in
operation.
[0003] Recently, sod cutters of a greatly simplified design have
been introduced. Such recent sod cutters are unable to perform many
functions of traditional sod cutters such as the ability to adjust
the depth of the oscillatory blades, but have shown that
traditional sod cutters have not met the requirements of many
market niches. However, such recent sod cutters have been unable to
satisfy such requirements and needs of the market because of
deficiencies inherent in their design.
[0004] Thus, a need exists for improved earthworking machines which
overcome the deficiencies of recently introduced machines and which
have application to not only the market niches exposed by such
recently introduced machines but also to traditional machines in
their manner of construction and operation.
SUMMARY
[0005] The present invention solves this need and other problems in
the field of earthworking machines and particularly in the field of
earthworking machines involving oscillatory movement by providing,
in the preferred form, a frame and its method of manufacture where
a frame plate and end plate are bent generally perpendicular to one
of two planar side plates and their free edges are welded to the
other of the side plates while the openings in side plates are
aligned. Thus, the frame is interconnected together in a three
dimensional configuration without fasteners and formed from two
planar elements.
[0006] In other aspects of the present invention, an axle assembly
which rotatably mounts at least one wheel is pivotably mounted to
the frame between a transport position where the outer periphery of
the wheel is spaced from a drive shaft and a working position where
the outer periphery of the wheel engages and is frictionally driven
by the drive shaft for propelling the earthworking machine.
[0007] In most preferred aspects of the present invention, a
friction enhancer in the form of a tubular member is removably and
slideably received on a shaft in a nonrotatable manner and has
noncircular outer periphery cross sections perpendicular to the
shaft for engaging the outer periphery of a wheel to drive the
wheel when the shaft is rotated.
[0008] In still other aspects of the present invention, a threaded
lock is threadably received in a first tube which slideably
receives a mast or in a lock plate spaced from the first tube and
includes a spring pin received in the threaded lock and located in
a gap between the tube and the lock plate to prevent the lock from
being threaded out of the first tube or lock plate, with the lock
being threadable into the first tube and lock plate to extend
against the mast.
[0009] Further, in aspects of the present invention, the center
portion of a U-shaped control of a shape and size corresponding to
a U-shaped handlebar is pivotably mounted relative to the U-shaped
handlebar about an axis spaced in front of and above the center of
the U-shaped handlebar. In an unactuated position, the leg portions
of the U-shaped control extend at an acute angle upward relative to
the legs of the U-shaped handlebar and is pivotal to engage the
legs of the U-shaped handlebar in an actuated position.
[0010] Furthermore, in other aspects of the present invention, a
handlebar is mounted to a mount in a working position for gripping
by an operator and in a storage position where the mast of the
handlebar is positioned over the earthworking machine for lifting
and hauling. In further aspects, a first linear portion of a mast
of a handlebar is slideably connected generally vertically to a
handlebar mount such that first and second legs of the U-shaped
handlebar extend generally horizontally rearward in a working
position and is slideably connected at an acute angle to vertical
such that the first and second legs of the U-shaped handlebar
extend forward and on opposite sides of the earthworking machine in
a storage position.
[0011] It is thus an object of the present invention to provide a
novel earthworking machine.
[0012] It is further an object of the present invention to provide
such a novel earthworking machine having very few moving parts and
a relatively light weight.
[0013] It is further an object of the present invention to provide
such a novel earthworking machine which is simple, durable and
easy-to-use.
[0014] It is further an object of the present invention to provide
such a novel earthworking machine utilizing a frame formed by
bending and welding planar elements.
[0015] It is further an object of the present invention to provide
such a novel earthworking machine utilizing a frame interconnected
in a three dimensional configuration without fasteners.
[0016] It is further an object of the present invention to provide
such a novel earthworking machine including a unique friction
drive.
[0017] It is further an object of the present invention to provide
such a novel earthworking machine utilizing a pivotal axle assembly
in a friction drive.
[0018] It is further an object of the present invention to provide
such a novel earthworking machine utilizing a slideable connection
where a threaded lock cannot be threaded out of the connection.
[0019] It is further an object of the present invention to provide
such a novel earthworking machine utilizing a unique control
assembly.
[0020] It is further an object of the present invention to provide
such a novel earthworking machine having a handlebar positionable
in a storage position for lifting and hauling and in a working
position for gripping during operation.
[0021] These and other objects and advantages of the present
invention will become clearer in light of the following detailed
description of an illustrative embodiment of this invention
described in connection with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The illustrative embodiment may best be described by
reference to the accompanying drawings where:
[0023] FIG. 1 shows a perspective view of a sod cutter fabricated
in accordance with the preferred teachings of the present invention
with the handlebar in the storage position.
[0024] FIG. 2 shows a side plan view of the sod cutter of FIG. 1
with the handlebar in the working position.
[0025] FIG. 3 shows an exploded perspective view of the sod cutter
of FIG. 1.
[0026] All figures are drawn for ease of explanation of the basic
teachings of the present invention only; the extensions of the
Figures with respect to number, position, relationship, and
dimensions of the parts to form the preferred embodiment will be
explained or will be within the skill of the art after the
following teachings of the present invention have been read and
understood. Further, the exact dimensions and dimensional
proportions to conform to specific force, weight, strength, and
similar requirements will likewise be within the skill of the art
after the following teachings of the present invention have been
read and understood.
[0027] Where used in the various figures of the drawings, the same
numerals designate the same or similar parts. Furthermore, when the
terms "axial", "radial", "first", "second", "side", "end", "inner",
"outer", "inside", "outside" "above", "forward", "rearward", "top",
"upper", "lower", "horizontal", "vertical", "front", "rear", and
similar terms are used herein, it should be understood that these
terms have reference only to the structure shown in the drawings as
it would appear to a person viewing the drawings and are utilized
only to facilitate describing the preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] An earthworking machine according to the preferred teachings
of the present invention is shown in the drawings and generally
designated 10. Generally, machine 10 will be suitable for use with
various types of earthworking involving an oscillatory blade
movement. Sod cutters, edging machines and pipe laying machines are
some examples of earthworking machines for which the present
invention will have particular application. In the most preferred
embodiment of the present invention, sod cutter 10 is an
improvement of the type shown and described in U.S. Pat. No.
5,009,270. For purpose of explanation of the basic teachings of the
present invention, the same numerals designate the same or similar
parts in the present figures and the figures of U.S. Pat. No.
5,009,270. The description of the common numerals and sod cutter 10
may be found herein and in U.S. Pat. No. 5,009,270, which is hereby
incorporated herein by reference.
[0029] Referring to the drawings in detail, sod cutter 10 comprises
a frame 12 having front wheels 14 and rear wheels 16. However,
frame 12 can be suitably moveably supported upon the turf by any
suitable means. Mounted on frame 12 is an internal combustion
engine 18 providing the propelling and oscillatory power for sod
cutter 10. Engine 18 has a centrifugal clutch 24 mounted thereto. A
belt 30 is entrained about clutch 24 and a driven pulley 28. Driven
pulley 28 is mounted on a rotatable shaft 32 having eccentrically
or axially offset portions 33.
[0030] A pair of oscillatory side arms 40 are suspended on opposite
sides of frame 12 from an upper pivot shaft 42. Whereas arms 40
swing or oscillate about upper shaft 42, arms 40 have attached at
their lower ends a U-shaped knife blade 44, with knife blade 44
extending horizontally or laterally between the lower ends of side
arms 40. Pitman arms 37 have first ends rotatably mounted upon
offset portions 33 and second ends rotatably mounted to arms 40
spaced from upper shaft 42 and knife blade 44.
[0031] According to the preferred teachings of the present
information, frame 12 is formed by bending and welding planar
elements or sheet material into a three dimensional configuration
of a generally parallepiped shape. Specifically, frame 12 includes
a pair of planar side plates 46 and 48 of a planar configuration
and generally of an L-shape. Side plate 46 includes an integral
motor mount plate 46a bent generally perpendicular from the front
portion of the upper edge of plate 46. An integral frame plate 46b
is bent generally perpendicular to the back portion of the upper
edge of plate 46 in the same direction as plate 46a. An integral
end plate 46c is bent generally perpendicular to the back edge of
plate 46 in the same direction as plates 46a and 46b. The upper or
top edge of plate 46c is welded to the back or rear edge of plate
46b, with plate 46c extending generally perpendicular to plate 46b.
Plate 46a is spaced from plate 46b perpendicular to plates 46a and
46b and spaced from plate 46b perpendicular to plate 46c. Plates
46a, 46b, and 46c have the same extent relative to plate 46. The
free edges of plates 46a, 46b, and 46c are welded to respective
edges of side plate 48 at generally perpendicular angles, with side
plates 46 and 48 being in a generally parallel and spaced relation.
Thus, the interconnection of plates 46 and 48 is accomplished
without fasteners.
[0032] Front wheels 14 are rotatably mounted on opposite sides of
frame 12 about an axle shaft 15 extending between front portions of
side plates 46 and 48 and spaced from and generally parallel to
plate 46a. In the preferred form, shaft 15 is held in place by
extending through and being welded to collars in turn welded to
side plates 46 and 48.
[0033] In the preferred form, sod cutter 10 further includes a
pivotable axle assembly 160 of a generally H-shape. Specifically,
assembly 160 includes a first leg 160a which is pivotably mounted
to the rear of frame 12. Particularly, in the preferred form, leg
160a is located between plates 46 and 48 and is pivotably mounted
therebetween such as by a pivot shaft extending through collars
welded to side plates 46 and 48, with the pivot axis of leg 160a
being parallel to and spaced from the rotational axis of wheels 14.
Wheels 16 are rotatably mounted on opposite ends of second leg 160b
which defines the rotational axis of wheels 16 spaced from and
parallel to leg 160a, with wheels 16 located on opposite sides of
frame 12. Legs 160a and 160b are held in a spaced, parallel
relation by a corrector 160c so that the axis of wheels 16 are
parallel and spaced from the axis of wheels 14 and leg 160a
[0034] In the preferred form, sod cutter 10 according to the
preferred teachings of the present invention includes a drive shaft
166 rotatably mounted in frame 12 about an axis which is spaced
from and parallel to the axes of shaft 32, wheels 14 and 16, and
leg 160a. In the most preferred form, shafts 32 and 166 are mounted
by flange type bearings 34 and 167 in openings formed in side
plates 46 and 48. It can be appreciated that flange type bearings
34 and 167 are less expensive than pillow block bearings which are
required if shafts 32 and 166 were mounted to a single
longitudinally extending frame member rather than spaced plates 46
and 48 as in the preferred form of the present invention.
[0035] Shaft 166 has a lateral extent generally equal to the
lateral extent of and for engaging the outer peripheries of wheels
16. First and second tubular members 168 are removably and
slideably received on the opposite ends of shaft 166 parallel to
the axis of shaft 166 and removably retained thereon in a
nonrotatable manner relative to shaft 166 such as by use of a
spring pin extending through tubular member 168 and shaft 166 at a
nonparallel angle to the axis of shaft 166. Tubular member 168 has
an outer periphery of a noncylindrical shape and in particular has
cross sections which are noncircular perpendicular to the axis of
shaft 166. In the preferred form, tubular member 168 has an outer
periphery having circular cross sections perpendicular to the axis
of shaft 166 and in the most preferred form having an inner
periphery having square cross sections perpendicular to the axis of
shaft 166 of a diameter generally equal to the diameter of shaft
166 and for slideable receipt on shaft 166. In the most preferred
form, tubular members 168 are formed by cutting and drilling square
steel bar stock.
[0036] Suitable provisions are provided for rotating shaft 166.
Specifically, in the preferred form, shaft 32 includes a sheave 170
located intermediate offset portions 33 and side 46, and shaft 166
includes a sheave 172 located intermediate first tubular member 168
and side 46. A belt 174 extends around sheaves 170 and 172 in a
generally tensioned manner by any suitable manner such as by moving
an idler pulley 176 against belt 174. In the preferred form, sod
cutter 10 includes an idler arm 178 mounted to side plate 46 about
a pivot axis parallel to but spaced from shafts 32 and 166, with
pulley 176 being pivotably mounted to the opposite end of arm 178
about an axis parallel to and spaced from the pivot axis of arm 178
and the axes of shafts 32 and 166.
[0037] Frame 12 in the most preferred form includes a handlebar
mounting tube 180. Specifically, in the most preferred form, tube
180 has inner and outer peripheries each having noncircular and
particularly square cross sections. In the most preferred form,
plate 46b intermediate its side edges and at its back edge includes
an opening 181 of a size and shape for slideable receipt of tube
180 adjacent to plate 46c. First and second tabs 182 are cut from
and bent inwardly generally perpendicularly from plate 46c at a
spacing for abutting on opposite sides of and for slideable receipt
of tube 180 received in opening 181. It can be appreciated that
opening 181 and tabs 182 allow for ease of positioning of tube 180
which in the preferred form is secured by welding.
[0038] In the most preferred form, a storage position tube 184 is
suitably secured to handle mounting tube 180 adjacent to its upper
end such as by welding. Tube 184 is at an acute angle in the order
of 45.degree. relative to tube 180, with the upper end of tube 184
located in front of the lower end. Tube 184 includes a through bore
186 for slideable receipt of a lynch pin 188 which in the preferred
form is tethered.
[0039] In the most preferred form, a C-shaped member 190 has its
free ends welded to the back side of tube 180 and with its center
portion defining a lock plate held relative to the outer periphery
of tube 180. A gap is defined between the outer periphery of tube
180 and the lock plate of C-shaped member 190. A handlebar lock 192
extends through an aperture or opening in member 190 through a nut
194 welded to tube 180 or member 190 and through an aperture or
opening formed in tube 180 between the inner and outer peripheries.
Thus, lock 192 is threadably received in one of tube 180 and the
lock plate of member 190. The gap exists between nut 194 and member
190 or nut 194 and tube 180 where nut 194 is positioned between
tube 180 and member 190 in the preferred form. However, the gap
could be formed between tube 180 and number 190 (which could have
other shapes) if member 190 is located intermediate nut 194 and
tube 180. A spring pin 196 or the like extends radially from lock
192 and is located in the gap defined by member 190. It can be
appreciated that pin 196 allows rotation of lock 192 but prevents
removal of lock 192 from tube 180 as pin 196 will abut with the end
of the gap before lock 192 is threadably out of and removed from
nut 194.
[0040] Sod cutter 10 includes suitable provisions for adjusting the
depth that knife blade 44 extends below the tangential plane of the
turf extending between wheels 14 and 16 or in other words the depth
of the sod cut by knife blade 44. Specifically, a depth adjuster
lever 198 is pivotably mounted relative to handle mounting tube 180
and frame 12 between its upper and lower ends about a lever axis
parallel to and spaced from the axes of shafts 32 and 166, wheels
14 and 16 and leg 160a. Lever 198 is operatively connected to
assembly 160 in the preferred form by a depth adjuster bar 200
pivotably mounted to leg 160b of assembly 160 and to the lower end
of lever 198. Thus, by pivoting lever 198, assembly 160 and wheels
16 are pivoted about the pivot axis of leg 160a relative to frame
12 and wheels 14 mounted thereto.
[0041] In the most preferred form, assembly 160 and wheels 16 are
lockable in a cutting or working position and a transport position.
Specifically, in the most preferred form, a generally U-shaped
trigger slide bracket 202 is mounted by its center to lever 198. A
first leg of an L-shaped trigger 204 is slideably mounted to lever
198 by being slideably received in apertures in the ears of bracket
202 for slideable movement perpendicular to the axis of lever 198
between an engaged position and a disengaged position. Trigger 204
is biased in the downward, engaged position such as by a spring 206
positioned around the first leg of trigger 204 sandwiched between
the upper ear of bracket 202 and a pin extending through the first
leg of trigger 204. For ease of manual actuation, lever 198
includes a handle extending parallel to but spaced from the second
leg of L-shaped trigger 204 so that the handle and second leg can
be grasped in the operator's hand and squeezed together to thereby
move trigger 204 against the bias of spring 206.
[0042] The lower end of the first leg of trigger 204 can be
received in notches fixed relative to frame 12 and particularly in
a depth adjuster brace 208 having an arched upper surface
concentric to the axis of lever 198. When trigger 204 is in a first
notch of brace 208, assembly 160 and wheels 16 are held in the
transport position with knife blade 44 located above a tangential
plane between wheels 14 and 16. When trigger 204 is in one of two
second notches of brace 208 of the most preferred form, assembly
160 and wheels 16 are held in the working position with knife blade
44 located below a tangential plane between wheels 14 and 16 at a
fixed depth corresponding to the particular depth associated with
the notch in which trigger 204 is received. In the preferred form,
notches are formed in brace 208 corresponding to different cutting
depths. Thus, in the working position, knife blade 44 will be
located below the turf upper surface and cuts a strip of sod as sod
cutter 10 is propelled forward.
[0043] It should be appreciated that in the transport position, the
outer peripheries of wheels 16 are radially spaced from tubular
members 168 and shaft 166. Thus, wheels 14 and 16 are free wheeling
and sod cutter 10 can be pushed by the operator to the desired work
area as knife blade 44 also does not engage the turf. However, in
the working position, wheels 16 engage shaft 166 and tubular
members 168 which act as friction enhancers between wheels 16 and
shaft 166. Due to the noncylindrical shape of tubular members 168,
rotation of shaft 166 and tubular members 168 causes wheels 16 to
rotate or be driven due to a friction drive between the outer
peripheries of pneumatic wheels 16 and tubular members 168. In this
regard, this friction drive does not utilize a gearing or similar
interlocking relation between tubular members 168 and wheels 16
which would require wheels 16 having a particular configuration and
which would be subject to clogging when engaging the turf. As
wheels 16 engage the turf, rotation of wheels 16 by rotation of
tubular members 168 causes sod cutter 10 to be propelled forward.
As shaft 166 is rotated by being rotatably connected to shaft 32,
knife blade 44 is simultaneously oscillating while sod cutter 10 is
being propelled forward to thereby cut a strip of sod.
[0044] Although friction drive of the type of the present invention
has been utilized in prior sod cutters, it is believed that the
friction drive of sod cutter 10 of the preferred form obtains
synergistic results. Specifically, prior friction drives in sod
cutters provided a bead of welding directly upon shaft 166.
However, if it was ever necessary to service shaft 166 or
components associated therewith, it was necessary to grind off the
welded bead. Additionally, when the welded bead wore off, it may be
possible to add another welded bead, with at least some operators
not having access to a welder, but often required replacement of
shaft 166 especially after repeated replacement of the welded
beads. According to the preferred teachings of the present
invention, tubular member 168 is the wear element, is formed by
simply cutting and drilling standard size square stock, and can be
readily removed and installed for either replacement or servicing
purposes.
[0045] Additionally, prior friction drives utilized screw type
adjustment of wheels 16 relative to frame 12. The problem is that
an operator could adjust wheels 16 relative to shaft 166 with too
little or too much pressure. Too little pressure could result in
excessive slippage between wheels 16 and shaft 166. Too much
pressure could result in excessive wear of wheels 16, shaft 166,
bearings 167, and the like. Sod cutter 10 according to the
preferred teachings of the present invention allows assembly 160 to
always be positioned relative to shaft 166 such that the pressure
of tubular members 168 upon wheels 16 is present within desired
levels. Additionally, a common operation is to cut a series of
strips of sod with the sod cutter being moved from its working
position to its transport position multiple times. Sod cutter 10 of
the preferred form can rapidly move between its working and
transport positions simply by pivoting lever 198 in comparison to
the time necessary to turn a screw type adjustment. Further, the
depth of knife blade 44 of the associated second notch engaged by
trigger 204 will be the same every time, sod cutter 10 according to
the teachings of the present invention is moved to its working
position for consistency, which could be variable for screw type
adjustment as the depth is dependent upon the number of times the
screw is rotated which is often very difficult to be consistent
every time.
[0046] Further, the square shape of the outer peripheries of
tubular members 168 according to the preferred teachings of the
present invention provides a variation in the contact pressure
applied between tubular members 168 and the pneumatic tires of
wheels 16. This variation in contact pressure causes a change in
the roundness of the outside diameter of the tires such that
debris, such as mud and grass clippings, will be more easily
dislodged from the tire and fall to the ground. Additionally, the
square shape of the outer periphery of tubular members 168
automatically furnish sharp comers which provide the variation in
the penetration depth of tubular member 168 into the outside
diameter of the pneumatic drive tire. The depth variation will
provide a constant change in the amount of friction created between
tubular members 168 and the tires making it nearly impossible to
cause slipping and the loss of power to drive wheels 16. Other
shapes for prior friction drives and particularly the circular
types utilizing welding beads, will slip easily and often when
moisture, mud or grass clippings are encountered during use.
[0047] Sod cutter 10 according to the preferred teachings of the
present invention includes a U-shaped handlebar 210 having legs
extending at an obtuse angle outwardly from the opposite ends of a
center portion. A U-shaped control 212 has a shape and size
generally corresponding to handlebar 210. Control 212 is pivotably
mounted relative to handlebar 210 about the center portion of
control 212 defining the pivot axis extending parallel to but
spaced in front of and above the center portion of handlebar 210.
Control 212 is pivotal between an unactuated position with the leg
portions extending at an acute angle upward relative to the legs of
handlebar 210 and a fully actuated position with the leg portions
engaging the the legs of handlebar 210. A jacketed cable 213 is
connected to the throttle for engine 18 of sod cutter 10. A spring
215 is connected to the throttle of engine 18 for biasing control
212 from the actuated position towards the unactuated position.
Other engine controls including but not limited to an on/off
switch, a fuel shutoff switch, and a choke can be located on
handlebar 210 such as mounted to a control box connected to
handlebar 210 and/or components connected to handlebar 210.
[0048] A mast 214 is secured to handlebar 210 and in the most
preferred form is removably secured to tube 180 or 184. In the most
preferred form, mast 214 includes a first linear portion 214a
extending from center portion of handlebar 210 at an obtuse angle
in the order of 135.degree. relative to the legs of handlebar 210.
Mast 214 includes a second linear portion 214b extending at an
obtuse angle in the order of 140.degree. relative to linear portion
214a and having an outer periphery of a size for slideable receipt
in the inner periphery of tube 180. The lower end of linear portion
214b includes a through bore 214c which in the most preferred form
is threaded at least adjacent the rear side thereof.
[0049] In the most preferred form, handlebar 210 can be positioned
relative to frame 12 in operating and storage positions. In the
operating position, linear portion 214b is inserted into and
slideably received in tube 180 until the aperture formed in tube
180 and handle lock 192 are aligned with bore 214c. At that time,
handle lock 192 can be rotated in nut 194 and inserted into and
most preferably threaded into through bore 214c. Alteratively, the
end of handle lock 92 can sandwich linear portion 214b against the
opposite side of tube 180, with bore 214c providing a positioning
as well as slide removal prevention function in this arrangement.
It should be appreciated that in the operating position, the legs
of handlebar 210 extend generally horizontally rearward and the
center portion extends generally horizontally at generally the
rearward extent of wheels 16. It can be appreciated that the
threadable or sandwich type connection between tube 180 and linear
portion 214b provided by lock 192 virtually eliminates relative
movement of handlebar 210 relative to tube 180 and frame 12 and
reduces the transmission of vibration to handlebar 210 and thus the
operator.
[0050] The shape and arrangement of control 212 according to the
preferred teachings of the present invention relative to handlebar
210 are advantageous as the operator's hand(s) tend to rest upon
and press down on handlebar 210 and thus control 212 in normal
operation of sod cutter 10. In the most preferred form of the
present invention, when control 212 is moved to the actuated
position, the throttle to engine 18 is opened to increase the
rotational speed of the output shaft and centrifugal clutch 24
which then rotates shafts 32 and 166 resulting in oscillation of
knife blade 44 and propelling of sod cutter 10 Particularly, it is
desirable to apply downward pressure on handlebar 210 during
operation of sod cutter 10 to increase traction of wheels 16 and
assist in forward movement of sod cutter 10. Thus, control 212
would be sandwiched against handlebar 210 when downward pressure is
placed upon handlebar 210. To stop operation, control 212 is simply
released. Thus, operation of sod cutter 10 according to the
teachings of the present invention is simple.
[0051] The location and position of wheels 16 of sod cutter 10
according to the preferred teachings of the present invention are
such that wheels 16 provide a means to hold the cut sod down on the
soil thus preventing it from rising and then bunching up and
causing sod cutter 10 to jam. Wheels 16 are placed close together
and positioned to be directly over the cut sod and close enough to
knife blade 44 to control the rising action of the cut sod. This
feature allows the operator of sod cutter 10 to continue the
cutting task uninterrupted without having to stop and clear sod
jams before resuming operation. This feature plus the geometry of
position of the other cutting elements allow sod cutter 10
according to the preferred teachings of the present invention to
cut sod in very wet conditions.
[0052] When it is desired to store sod cutter 10 including but not
limited to in the trunk or storage space of a vehicle, handle lock
192 is rotated in the unthread direction relative to nut 194 to
pass through hole 214c until handle lock 192 is in a noninterfering
relation to linear portion 214b to allow sliding of linear portion
214b relative to tube 180. It should be appreciated that according
to the preferred teachings of the present invention, lock 192 can
not be threaded completely out of nut 194 or be separated from sod
cutter 10. In particular, spring pin 196 will abut with the end of
the gap to prevent further movement therebeyond. This is an
especially advantageous feature when sod cutter 10 is utilized in a
rental environment where often separable components can be lost by
the rental customer.
[0053] After lock 192 is in a noninterfering relation, linear
portion 214b can be slid from tube 180. Once removed from tube 180,
handlebar 210 can be turned forward such that the legs of handlebar
210 extend forward of linear portion 214b. In particular, the first
leg on the right side of sod cutter 10 in the operating position is
positioned on the left side of sod cutter 10 in the storage
position, and the second leg on the left side of sod cutter 10 in
the operating position is positioned on the right side of sod
cutter 10 in the storage position. Linear portion 214b can be slid
into tube 184 until bores 186 and 214c are aligned at which time
pin 188 can be inserted therethrough to thereby lock linear portion
214b relative to tube 184. Due to the angle of tube 184 relative to
tube 180, the angle between portions 214a and 214b, and the angle
between portion 214a and handlebar 210, the center portion of
handlebar 210 generally abuts with engine 18 and the legs of
handlebar 210 extend downwardly therefrom on opposite sides of
engine 18. In the storage position, mast 214 can be utilized to
lift and haul sod cutter 10. It can be appreciated that in the
storage position, sod cutter 10 has a lesser longitudinal length
generally to the rear extent of wheels 16 rather than handlebar 210
when in the operating position and has a lesser height to the top
of lever 198 rather than control 212 when in the operating
position. The reduced size of sod cutter 10 according to the
preferred teachings of the present invention is advantageous for
reduced storage requirements but especially for shipping such as
from the manufacturer to the customer and for moving between work
sites and particularly in the rental environment where the rental
customer may wish to transport in an automobile, van or SUV rather
than in a pickup truck, or trailer as in commercial operations.
Additionally, it can be appreciated that sod cutter 10 can be
shipped in a relatively small shipping container while being
completely assembled. Once removed from the shipping container, sod
cutter 10 according to the teachings of the present invention can
be placed into its working position ready for use in a short time
and without requiring use of tools.
[0054] It should be appreciated that frame 12 according to the
teachings of the present invention is very strong and durable and
relatively inexpensive to fabricate. In particular, generally
frames are of two types and specifically those that include pillow
block bearings and those that include flange type bearings. For
ease of fabrication, it is desired to have the openings for flange
type bearings or for any other members which are desired to have
somewhat accurately placed to be stamped in the sheet material.
Bending the sheet material is not always consistent so forming
frame 12 from a single part containing two bends and properly
aligned paired holes in each of sides 46 and 48 is impossible.
Thus, prior to the present invention, frames were made of multiple
pieces connected together with fasteners to allow adjustment.
However, the costs of the fasteners and of assembly significantly
increased the cost as well as resulted in strength deficiencies.
The present invention overcomes these deficiencies by utilizing
jigs which align the openings of side plates 46 and 48 after plates
46a, 46b, and 46c are bent during the welding of the free edges of
plates 46a, 46b, and 46c to plate 48. Similarly, tube 180 can be
quickly welded in place. Thus, the use of fasteners is eliminated
and the costs of components and assembly are significantly reduced
while providing frame 12 of increased strength and lesser weight
according to the preferred teachings of the present invention, with
the total weight of sod cutter 10 of the preferred form being only
63.5 kilograms (140 pounds). The lesser weight of frame 12 and of
sod cutter 10 according to the teachings of the present invention
is a major factor in allowing ease of use of sod cutter 12 compared
to prior sod cutters.
[0055] It should be appreciated that sod cutter 10 is relatively
easy to operate for anyone from a novice homeowner to a
professional landscaper. Specifically, sod cutter 10 includes
relatively few moving parts and thus minimizes costs of fabrication
and servicing. Additionally, none of the components are needed to
be removed from sod cutter 10 for normal operation, with connection
components being either tethered or nonremovable. This is
especially advantageous for the rental environment. Because of its
light weight and ease of operation, sod cutter 10 according to the
teachings of the present invention can be used in many applications
including those of traditional sod cutters as well as others such
as for flower beds, sculpting lawns, patio installation and ball
field trimming where traditional sod cutters were not used because
of their size and complexity. Now that the basic teachings of the
present invention have been explained, many extensions and
variations will be obvious to one having ordinary skill in the art.
For example, although sod cutter 10 of the most preferred form
includes the combination of several, unique features believed to
obtain synergistic results, earthworking machines could be
constructed according to the teachings of the present invention
including such features singly or in other combinations. As an
example, the unique friction drive of the present invention could
be utilized in other types of frames including but not limited to
conventional frames.
[0056] Thus since the invention disclosed herein may be embodied in
other specific forms without departing from the spirit or general
characteristics thereof, some of which forms have been indicated,
the embodiments described herein are to be considered in all
respects illustrative and not restrictive. The scope of the
invention is to be indicated by the appended claims, rather than by
the foregoing description, and all changes which come within the
meaning and range of equivalency of the claims are intended to be
embraced therein.
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