U.S. patent application number 09/835421 was filed with the patent office on 2001-09-20 for signature delivery apparatus including two rotating buckets.
This patent application is currently assigned to Quad/Tech, Inc.. Invention is credited to d'Agrella, Ingermar S., Fox, Richard J., Schaefer, Karl P..
Application Number | 20010022421 09/835421 |
Document ID | / |
Family ID | 23119047 |
Filed Date | 2001-09-20 |
United States Patent
Application |
20010022421 |
Kind Code |
A1 |
Schaefer, Karl P. ; et
al. |
September 20, 2001 |
Signature delivery apparatus including two rotating buckets
Abstract
A delivery apparatus for sorting a single stream of signatures
into two or more streams, the apparatus includes two
counter-rotating bucket assemblies. Each bucket assembly includes a
plurality of buckets spaced from one another along a common axis.
The respective common axis of each bucket assembly is disposed
parallel to the common axis of the other. Each of the buckets of
one of the bucket assemblies is disposed adjacent to and in a
respective common plane with a respective one of the buckets of the
other of the bucket assemblies. Further, each of the buckets
includes a plurality of blades, the tips of the blades of each
bucket defining a circumference. A respective circumference of one
bucket overlaps the circumference of the other bucket disposed in
the common plane. Two neighboring blades have respective surfaces
defining a slot therebetween. Each slot includes a first generally
wedge-shaped portion defined by a first planar surface and a second
planar surface disposed at a first angle from the first planar
surface, and a second generally wedge-shaped portion defined by a
third planar surface and a fourth planar surface disposed at a
second angle from the third planar surface. The second angle is
smaller than the first angle.
Inventors: |
Schaefer, Karl P.;
(Brookfield, WI) ; d'Agrella, Ingermar S.;
(Sussex, WI) ; Fox, Richard J.; (Menomonee Falls,
WI) |
Correspondence
Address: |
MICHAEL BEST & FRIEDRICH, LLP
100 E WISCONSIN AVENUE
MILWAUKEE
WI
53202
US
|
Assignee: |
Quad/Tech, Inc.
Sussex
WI
|
Family ID: |
23119047 |
Appl. No.: |
09/835421 |
Filed: |
April 16, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09835421 |
Apr 16, 2001 |
|
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|
09291145 |
Apr 12, 1999 |
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6247692 |
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Current U.S.
Class: |
271/3.18 ;
271/287; 271/315 |
Current CPC
Class: |
B65H 2404/6591 20130101;
B65H 29/40 20130101 |
Class at
Publication: |
271/3.18 ;
271/287; 271/315 |
International
Class: |
B65H 020/00; B65H
005/00 |
Claims
What is claimed is:
1. A delivery apparatus for organizing a separated stream of
signatures into a shingled stream of signatures, the apparatus
comprising: a bucket operable to rotate around an axis, the bucket
including a plurality of blades with tips that define an outer
circle having a diameter of at least 32 inches, wherein a primary
surface of a leading blade together with a secondary surface of a
successive blade define a slot adapted to receive and slow down
signatures, the slots including inner ends defining an inner circle
having a diameter that is at least 24 inches.
2. The delivery apparatus of claim 1 further comprising a second
bucket that includes a plurality of blades having tips that define
an outer circumference, wherein the second bucket is disposed
adjacent to the other bucket such that the outer circle of one
bucket overlaps the outer circumference of the other bucket.
3. The delivery apparatus of claim 2, wherein the outer circle is
at least 32 inches and no fewer than 40 inches.
4. The delivery apparatus of claim 3, wherein the outer circle is
37.5 inches.
5. The delivery apparatus of claim 2, wherein the inner circle is
at least 24 inches and no fewer than 30 inches.
6. The delivery apparatus of claim 3, wherein the inner circle is
27 inches.
7. A delivery apparatus for organizing a separated stream of
signatures into a shingled stream of signatures, the apparatus
comprising: a bucket including at least 10 blades, the blades
including tips that define an outer circle having a diameter of at
least 32 inches, wherein a primary surface of a leading blade
together with a secondary surface of a successive blade define a
slot adapted to receive and slow down signatures.
8. The delivery apparatus of claim 7, wherein the outer circle is
at least 32 inches and no fewer than 40 inches.
9. The delivery apparatus of claim 8, wherein the outer circle is
37.5 inches.
10. The delivery apparatus of claim 7, wherein the bucket includes
at least 10 blades and no fewer than 14 blades.
11. The delivery apparatus of claim 10, wherein the bucket includes
twelve blades.
12. The delivery apparatus of claim 7 further comprising a second
bucket that includes a plurality of blades having tips that define
an outer circle, wherein the second bucket is disposed adjacent to
the other bucket such that the outer circle of the second bucket
overlaps the outer circle of the other bucket.
13. A delivery apparatus for organizing a separated stream of
signatures into a shingled stream of signatures, the apparatus
comprising: a bucket including at least 10 blades, wherein a
primary surface of a leading blade together with a secondary
surface of a successive blade define a slot adapted to receive and
slow down signatures, the slots including inner ends defining an
inner circle having a diameter that is at least 24 inches.
14. The delivery apparatus of claim 13, wherein the bucket includes
at least 10 blades and no fewer than 14 blades.
15. The delivery apparatus of claim 14, wherein the bucket includes
12 blades.
16. The delivery apparatus of claim 13, wherein the inner circle is
at least 24 inches and no fewer than 30 inches.
17. The delivery apparatus of claim 13, wherein the inner circle is
27 inches.
18. A delivery apparatus for organizing a separated stream of
signatures into a shingled stream of signatures, the apparatus
comprising: a bucket including at least 10 blades, the blades
including tips that define an outer circle having a diameter of at
least 32 inches, wherein a primary surface of a leading blade
together with a secondary surface of a successive blade define a
slot adapted to receive and slow down signatures, the slots
including inner ends defining an inner circle having a diameter
that is at least 24 inches.
19. The delivery apparatus of claim 18, wherein the inner circle is
at least 24 inches and no fewer than 30 inches.
20. The delivery apparatus of claim 19, wherein the bucket includes
at least 10 blades and no fewer than 14 blades.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a signature delivery
apparatus for a folder. In particular, the invention relates to a
signature delivery apparatus including two overlapping rotating
buckets which operate to feed signatures alternately to one of two
paths.
BACKGROUND OF THE INVENTION
[0002] In the printing industry, a desired image is repeatedly
printed on a continuous web or substrate such as paper. In a
typical printing process, the continuous web is slit (in the
longitudinal direction which is the direction of web movement) to
produce a plurality of continuous ribbons. The ribbons are aligned
one on top of the other, folded longitudinally, and then cut
laterally to produce a plurality of multi-page, approximately
page-length segments, each of which is termed a "signature". The
term signature also encompasses a single printed sheet that has or
has not been folded. Because more than one different signature can
be printed at one time, it is often desirable to separate the
different signatures by transporting successive signatures in
different directions or paths.
[0003] One way to accomplish the sorting of a single stream of
signatures is to use a diverter mechanism including a stationary
diverter wedge to divert successive signatures to one of two paths.
Examples of such diverter mechanisms are described in U.S. Pat.
Nos. 4,373,713 and 4,729,282.
[0004] Another way to accomplish the sorting of a single stream of
signatures into two or more streams is with the use of rotating
buckets (also known as fans, fan wheels, paddle fans, or rotary
flywheels). One known configuration for sorting signatures includes
two sets of rotating buckets, wherein the two sets have outer
diameters which overlap. This arrangement is disclosed in U.S. Pat.
No. 5,112,033. As described therein, each set of buckets includes
several identical buckets arranged at a spaced distance from one
another along a common axis. Each bucket has multiple blades which
define pockets or slots for receiving signatures. Each blade
includes a recess so that the blades do not collide when the two
sets of buckets rotate. Signature placement alternates from the
slots of the right set of buckets to the slots of the left set of
buckets to thereby sort the single stream of signatures into two
streams.
[0005] The use of recesses in the blades as described in U.S. Pat.
No. 5,112,033 has certain disadvantages. For example, a recess in
the blade presents an obstacle for a signature and may interfere
with the smooth entry or exit of the signature into or out of the
slot. The process of removing a signature from a slot is also
referred to as "stripping" the signature. Additionally, in one
embodiment described in the above-referenced patent, the recess in
the blade has a cover that acts like a spring. The cover can be
depressed, and when the force is removed, the cover will bounce
back. This cover gets depressed by the blade of the opposite bucket
once per signature that is processed in the associated slot. Thus,
the cover can wear out, break, or jam in the open or closed
position. Also, the dust created from the cutting process can cause
problems with jamming of the cover.
[0006] It is desirable to increase the operating speed of a
printing press as much as possible in order to increase the printed
product output. However, as the rotational speed of the buckets is
increased, it is more difficult to ensure the reliable operation of
the buckets while ensuring the quality of the signatures. For
example, signature quality problems that can occur at higher press
speeds include ink offset, dog-eared edges, and defects to both the
leading and trailing edges of the signatures. These and other
defects can lead to paper jams in the folder, resulting in press
downtime and expense.
SUMMARY OF THE INVENTION
[0007] It is a principal object of the present invention to provide
a signature delivery apparatus for a folder for sorting a single
stream of signatures into two or more streams. The delivery
apparatus includes two counter-rotating bucket assemblies. Each
bucket assembly includes a plurality of buckets spaced from one
another along a common axis. The respective common axis of each
bucket assembly is disposed parallel to the common axis of the
other. Each of the buckets of one of the bucket assemblies is
disposed adjacent to and in a respective common plane with a
respective one of the buckets of the other of the bucket
assemblies. Further, each of the buckets includes a plurality of
blades, the tips of the blades of each bucket defining a
circumference. The respective circumference of one bucket overlaps
the circumference of the other bucket disposed in the respective
common plane. Two neighboring blades on a bucket have respective
surfaces defining a slot therebetween. Each slot includes a first
generally wedge-shaped portion defined by a first planar surface
and a second planar surface disposed at a first angle from the
first planar surface, and a second generally wedge-shaped portion
defined by a third planar surface and a fourth planar surface
disposed at a second angle from the third planar surface. The
second angle is smaller than the first angle.
[0008] Also disclosed herein is an improved stripper profile which
lessens the impact shock on the leading edge of the signature
during signature stripping from the bucket.
[0009] Other features and advantages of the invention will become
apparent to those skilled in the art upon review of the following
detailed description, claims and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic diagram of a pinless folder
incorporating a delivery apparatus in accordance with the present
invention;
[0011] FIG. 2 is an illustration of two bucket assemblies and two
stripping assemblies in accordance with the present invention;
[0012] FIG. 3 is a side view of a bucket assembly and associated
stripping assembly in accordance with the present invention;
and
[0013] FIG. 4 is a partial illustration of two overlapping buckets
showing in detail the shapes of the blades and the slots.
[0014] Before one embodiment of the invention is explained in
detail, it is to be understood that the invention is not limited in
its application to the details of construction and the arrangement
of components set forth in the following description or as
illustrated in the drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in
various ways. Also, it is to be understood that the phraseology and
terminology used herein is for the purpose of description and
should not be regarded as limiting.
BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] Illustrated in FIG. 1 of the drawings is a schematic of a
folder 10 which is a portion of a high speed printing press. The
folder 10 includes a forming section 12, a drive section 14, a
cutting section 16, and a delivery section 18.
[0016] In particular, the forming section 12 includes a generally
triangularly shaped former board 20 which receives a web of
material (or several longitudinally slit sections of the web called
ribbons, wherein the ribbons are typically aligned one on top of
the other) and folds the same longitudinally (i.e., in the same
direction as the web travels). The folded web is then fed
downwardly under the influence of a pair of squeeze rolls 21 to the
drive section 14. The drive section 14 includes pairs of upper and
lower drive rolls, 22 and 24 respectively. These drive rolls
transport the web to conditioning rolls 26 in the cutting section
16. The web then passes into engagement with a cutting device 28.
The web is segmented by the cutting device 28 into a plurality of
signatures 30. Suitable timing means, known to those of ordinary
skill in the art, provide accurate longitudinal registration of the
image on the web with respect to the cutting device 28 to ensure
proper cut locations for the web segments.
[0017] Successive signatures 30 enter the delivery section 18 along
a delivery path 32, aided by belts or transport tapes 34. The
opposed tapes 34 are shown apart for clarity, but are actually very
close together and press on each other with the signature between
them. The delivery section 18 also includes stripping assemblies 60
and two bucket assemblies 36. The two bucket assemblies operate to
sort the single stream of signatures into two streams and also slow
down the signatures. The stripping assemblies 60 operate to remove
a signature at a time from a respective bucket 38. The signature
then falls upon a conveyor (not shown) where successive signatures
are arranged in a shingled stream. The movement of the signatures
on the shingling conveyor can be to the left or the right or out of
the plane of FIG. 1.
[0018] Referring to FIGS. 2 and 4, the configuration of each bucket
assembly 36 is illustrated in detail. Although only one bucket 38
per bucket assembly 36 is shown in these figures, each bucket
assembly 36 includes identical buckets 38 spaced at predetermined
distances along a respective common shaft 39, as shown in FIG. 3.
In both FIGS. 2 and 4, the buckets on the left rotate in a
clockwise direction, and the buckets on the right rotate in a
counterclockwise direction.
[0019] In the preferred embodiment, each bucket 38 includes twelve
blades 40 extending outwardly from an inner circular portion 42.
The tips 44 of the blades define an outer circle having an outer
circumference 45. The outer circumference 45 of the left set of
buckets overlaps the outer circumference 45 of the right set of
buckets. In the preferred embodiment, the diameter of the outer
circle is 37.5 inches and the center to center spacing of the
bucket assemblies is 36 inches such that there is 1.5 inches of
overlap.
[0020] The blades 40 are constructed so as to prevent collisions
between blades from opposing buckets when the buckets 38 are
rotating. In particular, as best seen in FIG. 4, each blade 40
includes a primary blade surface 46 and a secondary blade surface
48. The primary blade surface 46 of one blade and the secondary
blade surface 48 of a successive blade together define a slot 49
for receiving signatures.
[0021] The primary blade surface is the main surface that the
signature slides on as it enters the bucket slot. In particular,
each primary blade surface 46 is composed of three portions AB, BC,
and CD. Viewed in profile, portions AB, BC, and CD correspond to
segment AB, which is a straight line, segment BC, which is an arc,
and segment CD, which is also an arc. In the preferred embodiment,
segment AB has a length of five inches, tangentially connected
segment BC has a twenty four inch radius and a length of six
inches, and tangentially connected segment CD has a 4.0 inch radius
and a length of three inches. Thus, the slot 49 has a length
measured along the primary blade surface 46 of fourteen inches and
is intended to receive a signature that is eleven inches long. The
longer slot allows room for the signature to bounce back slightly
from the slot end DE, without interfering with the operation of the
rotating buckets. The three inches of extra slot length also allows
the signature to be completely within the slot before the signature
slows down during the last three inches of travel as it approaches
slot end DE.
[0022] The secondary blade surface is composed of six surface
portions EF, FG, GH, HJ, JK, and KL. Again as viewed in profile,
these portions include corresponding segments EF, FG, GH, HJ, JK,
and KL. In particular, segment EF is an arc having a radius drawn
from the same center as segment CD. Similarly, segment FG is an arc
having a radius drawn from the same center as segment BC.
[0023] The slot width A is therefore constant in the region from E
to G, and in the preferred embodiment is 0.125 inches wide. Segment
GH is an arc, segment HJ is a straight line, segment JK is an arc,
and segment KL is a straight line. Segments AB and KL and the area
between these segments provide the necessary clearance so that an
opposing bucket blade does not collide with a given bucket blade.
Further in the preferred embodiment, segment EF has a 3.875 inch
radius, segment FG has a 23.875 inch radius, segment GH has a four
inch radius, and segment JK has a four inch radius.
[0024] At the tip 44 of a blade 40, portion LM can either be a
planar surface or a convex surface that matches the circumference
of the outer circle 45. The blade edges 50 (shown in FIG. 3) of the
primary and secondary blade surfaces 46, 48 on both sides of the
blade are rounded. The rounded edges reduce or eliminate the sharp
edges that may tear or otherwise cause damage to a signature
30.
[0025] Thus, the primary blade surface 46 and the secondary blade
surface 48 of a successive blade together define slots 49 for
receiving signatures. As shown in FIG. 4, the slots 49 include a
first wedge-shaped section 52, a second wedge-shaped section 54,
and a constant width section 56. The first wedge-shaped section 52
is defined by planar surfaces partially including portions AB and
KL. The second wedge-shaped section 54 is defined by curved
surfaces partially including portions AB, BC and portions GH, HJ,
and JK. The first wedge-shaped section 52 prevents opposing blades
40 from hitting the bucket 38 and allows clearance for the
signature insertion as the bucket rotates. The second wedge-shaped
section 54 functions to further channel the signature into the
constant width section 56 of the slot and prevents flaring out of
the leading edge of the signature which could cause dog ears on the
leading edge.
[0026] The slot 49 meets a tangent to the inner circular portion 42
at an angle of approximately forty-five (45) degrees. Additionally,
the slot ends, surfaces DE, are on the circumference of the inner
circular portion and also have rounded edges on both front and
rear. In the preferred embodiment, the diameter of the inner
circular portion 42 measures twenty-seven inches. For a given
rotational bucket speed, the slot ends in a bucket having a larger
inner diameter travel at a higher rate of speed than do slot ends
in a bucket having a smaller inner diameter. Thus, the impact force
between a moving signature and the slot end is reduced the faster
the slot ends travel because the speed difference between the two
is reduced.
[0027] The speed of the transport tapes 34 is designed to be
approximately 8 to 15% greater than the speed of the web prior to
the cutting device. This speed increase creates a gap between
successive signatures 30 along the delivery path 32. The size of
this gap is independent of machine speed and depends only upon the
speed gain of the transport tapes 34 and the signature length. The
larger the speed gain of the tapes, the larger the resulting gap
between signatures. This gap between successive signatures makes
the diverting of signatures to alternate buckets possible.
[0028] The angular speed of each bucket is such that each bucket
turns one angular slot distance (30 degrees for a bucket with 12
slots) for everv two signatures fed from the cutting device 28.
Each bucket turns at such an angular speed so that it receives
every other signature during the diverting process. To achieve the
proper speeds, the bucket shaft is driven by the printing press
line shaft with the proper speed reduction to take into account the
number of slots per bucket and the fact that every other signature
is directed to a single bucket. A bucket having a smaller number of
slots per given circumference has to turn at a faster angular speed
(RPM) than one with more slots in order to receive all the
signatures coming towards it.
[0029] In operation, the transport tapes 34 move the signatures 30
to a location in the vicinity of the two bucket assemblies 36 along
delivery path 32, which is the centerline between the two buckets.
A signature 30 strikes a primary blade surface 46 of a blade 40
momentarily disposed across the signature path in a position for
receiving the signature. The tip 44 of the blade is about 0.125 to
0.250 inches across the center line 32 as the leading edge of the
signature hits the surface 46. The signature strikes the surface 46
at an angle (shown in FIG. 4) of approximately twenty degrees or
less. The smaller the angle is made, the smaller is the impact
force on the leading edge 29 of the signature. The signature 30 is
directed by the primary blade surface 46 into the slot 49 formed
between adjacent blades. The frictional contact with the primary
blade surface 46 and the ever tightening radius of curvature slows
down the signature 30 as it continues in the slot 49.
[0030] The tips 44 of the next blades to cross center line 32 are
tips from the opposite set of buckets 36. The left hand bucket is
phased with respect to the right hand bucket such that the blades
from the two set of buckets much properly without hitting each
other. These tips 44 act to deflect the trailing edge 31 of the
signature in order to prevent the trailing edge 31 from
accidentally whipping around the tip 44 of the previous bucket
blade. The end of the signature is rounded so that it does not
damage the signature during this hit process. The next signature 30
is then transported by the tapes 34 into the vicinity of these tips
and the signature is placed into this opposite set of blades. Thus,
the signature placement into the slots alternates between the two
bucket assemblies. These steps are repeated in order to place
successive signatures alternately into the two bucket assemblies,
to thereby separate the single stream of signatures into two
streams.
[0031] In order to remove the signatures from the slots, a
stripping assembly 60 is utilized, as illustrated in FIGS. 1-3. The
stripping assembly 60 includes a pivot arm 62, several strippers
64, and a mounting bar 66. The pivot arm 62 is mounted to remain
stationary relative to the axis of the buckets during rotation
thereof, but is adjustable around the bucket axis. As the pivot arm
is adjusted around the bucket axis, the position of the strippers
64 are adjusted relative to the slots. The purpose of this
adjustment is so that one can adjust the amount of time between the
hit at the end of the bucket slot and the subsequent hit on the
stripper. The two hits should not be too close together in time
because it is desirable to have two separate distinct hits to
dissipate the kinetic energy instead of only one hit on the
stripper. As FIG. 3 illustrates, the strippers 64 are mounted in
spaced apart relation along the mounting bar 66. Each stripper 64
is spaced from a respective bucket 38. The strippers 64 are
individually adjustable along the length of the mounting bar
66.
[0032] It is desirable for a signature 30 to approach the inner
circular portions 42 of the buckets 38 tangentially to reduce the
impact force as the signature 30 hits the inner circular portion at
the slot end DE. However, for efficient signature removal by the
stationary strippers, a relatively large angle is preferable
because the impact force is less when the signature hits the
stationary stripping assembly 60 and is ejected from the slots 49.
Thus, an angle of forty-five degrees was chosen as a compromise
between these two competing requirements.
[0033] As best seen in FIG. 2, each stripper 64 includes a smooth
surface, depicted as curve 65, on which the leading edge 29 of a
signature strikes. Ideally, the stripper curve 65 is one that
decelerates a signature over as long of a time period as possible
so that the impact force acting on the leading edge 29 of the
signature 30 when the signature hits the stripper 64 is kept to a
minimum. A smaller impact force on the stripper at a given
rotational bucket speed prevents damage to the leading edge 29 of
the signature 30 and allows for higher rotational bucket speeds
which means faster printing press running speeds. In addition, the
direction of the ejection force that pushes the signature out of
the slot 49 should be in the direction of segment EG (i.e., along
the slot length) rather than perpendicular to segment EG (i.e.,
perpendicular to the sides of the slots). An ejection force having
too large of a force component perpendicular to the segment EG can
damage or tear the signature 30 during the stripping process. This
is especially true at slot end DE where the signature 30 first
makes contact with the stripper 64 to start the stripping process.
Once the signature 30 has started to move partially out of the slot
49 after the initial hit with the stripper 64 (after the leading
edge 29 of the signature 30 has been pushed out by about one inch
from the slot end DE), then the impact force diminishes and its
direction does not have to remain parallel to the direction of the
slot.
[0034] The impulse time can be increased by inclining the signature
ejection force slightly away from the direction of the slot length,
resulting in a small component of the signature ejection force that
is perpendicular to the direction of the sides of the slot. In the
preferred embodiment of the stripper 64, the curve 65 results in an
impact force that is gradually increased from within 10 degrees of
the direction of the slot length during the first portion of the
stripping process to within 20 degrees during the end of the
stripping process.
[0035] In the preferred embodiment, the stripper 64 is constructed
out of a 3/4 inch thick sheet of plastic such as Delrin. This
material allows the leading edge of the signature to slide easily
along the stripper surface 65 during the stripping process. The
impact energy dissipated at the bucket slot end DE associated with
a signature collision with surface DE is less than 70% of the total
impact energy dissipated by the signature 30 as it is brought to a
stop at the end of the printing process. The impact energy of a
signature collision with the stripper is greater than 30% of the
total impact energy. The stripper surface 65 is also rounded along
its two side edges to prevent signature damage.
[0036] The delivery apparatus of the present invention organizes a
separated stream of signatures into a shingled stream of signatures
and includes a bucket having at least ten blades, and preferably
includes at least ten blades and no fewer than 14 blades, and even
more preferably includes 12 blades. In addition, the inner ends
slots on the bucket define an inner circle having a diameter that
is at least 24 inches, and preferably is at least 24 inches and no
fewer than 30 inches, and even more preferably is 27 inches. The
tips of the blades on the buckets define an outer circle having a
diameter of at least 32 inches, and is preferably at least 32
inches and no fewer than 40 inches, and even more preferably is
37.5 inches.
[0037] Various features and advantages of the invention are set
forth in the following claims.
* * * * *