U.S. patent number 3,661,243 [Application Number 04/877,110] was granted by the patent office on 1972-05-09 for conveyor system.
This patent grant is currently assigned to Kraftco Corporation. Invention is credited to Robert J. Piatek.
United States Patent |
3,661,243 |
Piatek |
May 9, 1972 |
CONVEYOR SYSTEM
Abstract
An apparatus for transferring a plurality of individual units
from a conveyor having one velocity in a given direction and
changing the velocity of the units to a second value in the same
direction. The units are engaged individually by elements of a
second conveyor having a velocity component in the given direction
the same as that of the units at the time of engagement of the
elements with the units.
Inventors: |
Piatek; Robert J. (Prospect,
IL) |
Assignee: |
Kraftco Corporation (Chicago,
IL)
|
Family
ID: |
27088848 |
Appl.
No.: |
04/877,110 |
Filed: |
November 17, 1969 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
621095 |
Feb 23, 1967 |
3479024 |
Nov 18, 1969 |
|
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Current U.S.
Class: |
198/475.1;
198/449; 198/792; 198/800; 198/802 |
Current CPC
Class: |
B65G
47/681 (20130101); B65B 35/54 (20130101) |
Current International
Class: |
B65B
35/54 (20060101); B65B 35/30 (20060101); B65G
47/68 (20060101); B65g 047/26 () |
Field of
Search: |
;198/20,32,34,76 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Sroka; Edward A.
Parent Case Text
This application is a division of application Ser. No. 621,095,
filed Feb. 23, 1967, for Method and Apparatus for Arranging
Articles in a Row, now U.S. Letters Pat. No. 3,479,024, issued Nov.
18, 1969.
Claims
I claim:
1. A conveyor system for changing substantially the velocity of
continuously traveling units without substantial shifting of the
arrangement of the units from a given disposition relative to each
other, comprising, in combination, a first conveyor having a
surface for supporting and continuously advancing a plurality of
units along a first path at a predetermined linear velocity with
the units thereon disposed in predetermined positions relative to
each other, and a second conveyor for receiving said units from
said first conveyor and for advancing said units upwardly along a
second path at a linear velocity substantially different from the
linear velocity imparted to the units by said first conveyor, said
second conveyor having a plurality of upwardly moving carrier
unit-supporting surfaces each adapted to receive one of said units,
said first and second conveyors being disposed relative to each
other with said second path intersecting said first path at an
angle such that the component of the linear velocity of each of
said unit-supporting surfaces of said carriers in the direction of
movement of the unit-supporting surface of said first conveyor at
the intersection of said paths is equal to the linear velocity of
the unit-supporting surface of said first conveyor at said
intersection so that the only significant additional force imparted
to the unit is in the direction substantially normal to the unit
receiving surface of said conveyors, and the arrangement of the
units relative to one another will not be effected, said conveyors
being adapted to effect a transfer of units between said first and
second conveyors at said point of intersection.
2. A conveyor system comprising, in combination, a first conveyor
having a surface adapted to support and continuously advance a
plurality of units along a first path at a predetermined linear
velocity, and a second conveyor having a plurality of carriers
defining unit-supporting surfaces each adapted to advance a single
one of said units along a second path at a linear velocity
different from the linear velocity imparted to the units by said
first conveyor, said first and second conveyors being disposed
relative to each other with said second path intersecting said
first path at an angle such that the component of the linear
velocity of each of said unit-supporting surfaces of said conveyors
in the direction of movement of the unit-supporting surface of said
first conveyor at the intersection of said paths is equal to the
linear velocity of the unit-supporting surface of said first
conveyor at said intersection, said conveyors being adapted to
effect a transfer of units between said first and second conveyors
at said point of intersection, said portion of said path of said
second conveyor being arcuate and a tangent to such arcuate portion
at said point of intersection forming with said given direction an
angle whose cosine is equal to the ratio of said first velocity
component in the given direction to the resultant of the velocities
of each of said elements in the given direction and in a direction
normal thereto at the intersection point.
3. A conveyor system comprising, in combination, a first conveyor
having a surface adapted to support and continuously advance a
plurality of units along a first path at a predetermined linear
velocity, and a second conveyor having a plurality of carriers
defining unit-supporting surfaces each adapted to advance a single
one of said units along a second path at a linear velocity
different from the linear velocity imparted to the units by said
first conveyor, said first and second conveyors being disposed
relative to each other with said second path intersecting said
first path at an angle such that the component of the linear
velocity of each of said unit-supporting surfaces of said conveyors
in the direction of movement of the unit-supporting surface of said
first conveyor at the intersection of said paths is equal to the
linear velocity of the unit-supporting surface of said first
conveyor at said intersection, said conveyors being adapted to
effect a transfer of units between said first and second conveyors
at said point of intersection, said first conveyor path and said
given direction being horizontal at said intersection point and
said portion of said second conveyor path at the intersection point
being a vertically ascending arcuate portion and beyond that point
along the second path merging with a straight horizontal portion,
the acceleration of each of said units and the element engaging the
same being essentially vertical at said intersection point with
velocities of the elements becoming ultimately horizontally
directed as the unit and element advance into said horizontal
portion of said second path.
4. A conveyor system comprising, in combination, a first conveyor
having a surface adapted to support and continuously advance a
plurality of units along a first path at a predetermined linear
velocity, and a second conveyor having a plurality of carriers
defining unit-supporting surfaces each adapted to advance a single
one of said units along a second path at a linear velocity
different from the linear velocity imparted to the units by said
first conveyor, said first and second conveyors being disposed
relative to each other with said second path intersecting said
first path at an angle such that the component of the linear
velocity of each of said unit-supporting surfaces of said conveyors
in the direction of movement of the unit-supporting surface of said
first conveyor at the intersection of said paths is equal to the
linear velocity of the unit-supporting surface of said first
conveyor at said intersection, said conveyors being adapted to
effect a transfer of units between said first and second conveyors
at said point of intersection, said first conveyor path and said
given direction being horizontal at said intersection point, said
portion of said second conveyor path at the intersection point
being a vertically ascending arcuate portion, and a tangent to such
arcuate portion forming with the horizontal an angle whose cosine
is equal to the ratio of the horizontal velocity of the first
conveyor at the intersection point to the resultant of the
horizontal and vertical velocities of each of said elements at the
intersection point.
Description
This invention relates generally to a conveyor system for handling
a plurality of individual units such as cheese slices and, more
particularly, to a system for changing the velocity of such units,
for example, accelerating the units as may be desired when
converging a plurality of adjacent moving lines of individual
cheese slices into a single output line of individual cheese
slices.
Presliced cheese is a readily saleable item due to the ease with
which it may be used in the preparation of food, both at home and
on a commercial basis in restaurants, etc. In one type of automated
system for making presliced cheese, a continuous sheet of warm
cheese is cooled by passing it over a large chilled cylindrical
roll. As the sheet of cheese leaves the chilled roll, it is slit to
form continuous ribbons, each of which is then guided over suitable
means and through a cutting station. As the ribbons move through
the cutting station, they are cut transversely of their length to
form individual cheese "slices" which move in lines from the
cutting station. The slices are then stacked and wrapped in
moisture proof airtight packages, preferably by automated
means.
Naturally, it is costly to provide a separate automated wrapping
operation for each ribbon of cheese moving from the chill roll.
Furthermore, it is possible to build automatic wrapping machines
having a capacity considerably greater than that which a single
ribbon of cheese moving from the cheese roll could provide. It is
therefore desirable that the individual cheese slices in a
plurality of rows formed by cutting a plurality of ribbons at a
cutting station be converged into a single moving composite line of
individual cheese slices. Such converging may be effected by
accelerating the slices to a velocity greater than their velocity
as they leave the cutting station, thereby spacing the slices so
that they may be shifted transversely into alignment in a single
row.
Accordingly, it is an object of the invention to provide an
improved apparatus for changing the velocity of a plurality of
individual units such as cheese slices advancing in a row.
Another object of the invention is to provide a novel conveyor
system for accelerating a plurality of individual cheese slices
while maintaining close control over the position of the slices so
as to avoid slippage and misalignment of the slices.
A more detailed object is to provide a novel conveyor system in
which a plurality of cheese slices advancing horizontally at one
velocity are picked up individually and accelerated to a higher
horizontal velocity.
Various other objects of the invention, and the various advantages
of the invention, will become apparent to those skilled in the art
from the following description taken in connection with the
accompanying drawings wherein:
FIG. 1 is a schematic diagram of a cheese packaging system
incorporating the invention;
FIG. 2 is a perspective view of a portion of a chill roll and
various elements associated therewith used in the cheese packaging
system of FIG. 1;
FIG. 3 is a perspective view of an apparatus for cutting cheese
ribbons used in the system of FIG. 1;
FIG. 4 is an enlarged sectional elevational view taken along the
line 4--4 of FIG. 3;
FIG. 5 is a top plan view showing a preferred pattern in which the
cheese ribbons are cut by the apparatus of FIGS. 3 and 4;
FIG. 6 is a top plan view of an apparatus forming a portion of the
system of FIG. 1;
FIG. 7 is a fragmentary elevational view of the apparatus of FIG.
6;
FIG. 8 is an enlarged sectional end view taken along the line 8--8
of FIG. 7;
FIG. 9 is an enlarged sectional end view taken along the line 9--9
of FIG. 7;
FIG. 10 is a sectional plan view taken along the line 10--10 of
FIG. 7; and
FIGS. 11 through 14 are fragmentary elevational views, partially in
section, illustrating successive steps in the operation of a
portion of the apparatus of FIG. 7, as viewed in the direction of
the arrows 14--14 of FIG. 10.
The invention is shown in the drawings for purposes of illustration
embodied in apparatus for handling individual slices 22 of cheese
in each of a plurality of single file rows 21 which have been
transformed from a plurality of ribbons 20. In the illustrated
embodiment, a continuous sheet of cheese 24 is slit to provide the
ribbons 20 which are advanced in side-by-side relation to a cutter
26. The cutter transforms each of the ribbons into a row of slices
22, thereby creating advancing side-by-side rows 28 of slices equal
in number to the original number of ribbons 20.
Individual slices are then selected from the multiple rows 28 in a
predetermined order by a converger 29 and shifted into successive
alignment with one another to form the desired lesser number of
single file rows 21, these rows representing a combination of
several of the ribbons 20. The single file rows 21 are then
delivered to a wrapping and packaging apparatus 30. After being
formed from the ribbons 20 and prior to achieving single file
orientation in a composite row 21, the individual slices 22 are
accelerated to a given output velocity which closely approximates
the product of the number of ribbons combined into one row and the
velocity of the ribbons.
In the illustrated embodiment, 16 ribbons are combined or converged
to provide four single file rows of slices. The invention is not
limited, of course, to the transformation of any specific number of
ribbons into a specific number of rows of slices and the particular
arrangement selected is intended by way of illustration and not
limitation. The following discussion will be directed principally
to the convergence of eight ribbons into two single file rows, it
being understood that convergence of the remaining eight ribbons is
accomplished in an identical manner.
More specifically, and with reference to FIG. 2, the sheet 24 of
cheese is produced through the use of a chill roll 36 onto which
molten cheese is allowed to flow and cool. The sheet is removed
from the chill roll by means of a scraper 37 and passed over a
takeoff roll 38 where it is slit into a plurality of ribbons by a
plurality of disc blades 41 mounted on a suitable axle 39. After
being cut, the individual ribbons are passed over a guide roll 42
supported by a pair of arms 43, only one of which is shown in FIG.
2.
When a long chill roll is utilized and, thus, a large number of
cheese ribbons are produced, it has been found convenient to employ
at least two automatic wrapping and packaging machines 30 and to
divide the plurality of cheese ribbons into several groups, each
group serving a corresponding one of the wrapping machines. Space
considerations are often such that the wrapping machines must be
spaced laterally from each other or from a position in direct
alignment with the ribbons as they leave the takeoff roll 38. In
order to effect a spacial separation of the plurality of adjacent
ribbons into a number of groups, the ribbons are first collated to
move them in a stack parallel with the axis of the chill roll, and
then are decollated in separate groups having the desired
spacing.
The collating operation is performed by a plurality of flanged
collator rollers 44 which are mounted for rotation about axes which
are disposed to effect a 90.degree. twist in each of the cheese
ribbons. A decollator conveyor 45 is disposed beneath the collator
rollers 44 and the ribbons are stacked one upon the other on this
conveyor as they leave the rollers and are moved in a direction
parallel to the axes of the chill roll 36 and the takeoff roll
38.
Decollating of the stacked ribbons carried on the decollator
conveyor 45 may be accomplished in groups at desired positions
along the path of the decollator conveyor. In FIG. 1, the 16
ribbons formed are decollated in groups of eight in order to feed
two wrapping machines 30. FIG. 2 is an enlarged view in perspective
of the decollating of eight of the cheese ribbons. Decollating is
accomplished by means of a plurality of flanged decollator rollers
46 which have axes parallel to the axes of the collator rollers 44.
The decollator rollers are disposed beneath the moving stack of
cheese ribbons just past the end of the decollator conveyor 45. The
ribbons are collated or stacked with each successive ribbon from
right to left being supported on top of the next preceding ribbon;
the stack of ribbons is decollated by diverting the ribbons one at
a time from the bottom of the stack. Thus, the first ribbon into
the stack is the first out of the stack.
After passing over and around a given one of the decollator rolls
46, the lowermost cheese ribbon of the stack is directed
downwardly, twisted approximately 90.degree., and guided around one
of a plurality of horizontal flanged rollers 47 disposed in axial
alignment with each other and supported on a common shaft. After
passing around a horizontal roller 47, each of the cheese ribbons
engages and is supported on a horizontal moving decollator
discharge conveyor 47a, only a portion of which is shown in the
drawings (FIG. 2). Thus, the cheese ribbons, as they move on the
discharge conveyor 47a, are disposed adjacent each other, are
coplanar, and are moving at the same generally constant speed. The
discharge conveyor 47a delivers the ribbons to a cutter conveyor 48
which in turn delivers cut slices 22 to the converger 29.
The cutter conveyor 48 (FIG. 3) operates in a timed relationship
with the decollator discharge conveyor 47a, with the cutter 26, and
with the converger 29 so that the size of the slices and their
removal from the conveyor may be accurately controlled. The
conveyor 48 comprises a plurality of continuous timing belts 49
provided with transversely extending ribs 50 and grooves 51 on
their under surface. Alternate belts 49a are supported at their
forward ends by splined pulleys 65 rotatably carried individually
on the forward ends of brackets 67. The remaining belts 49b are
supported at their forward ends by splined pulleys (not shown)
carried on a shaft 69. The shaft 69 is rotatably mounted somewhat
rearwardly of the rollers 65 so that the belts 49b terminate
rearwardly of the termination of the belts 49a. The earlier
termination of the belts 49b provides gaps 71 intermediate the
forward ends of the belts 49a to facilitate the removal of the
cheese slices from the belts, as will become apparent shortly.
As will be noted from FIG. 3, the ribbons 20, prior to being cut,
are supported so as to span the belts 49b, with an edge portion of
each ribbon resting upon the edge portion of each of two belts 49a.
This relationship between the cheese and the belts is preserved
after the ribbons are cut. Thus, each of the slices 22 of the rows
28 also spans a belt 49b and is supported at its side edges by each
of a pair of the belts 49a. When the cheese slices reach the area
where the belts 49b have terminated, therefore, they span the gaps
71 for a brief duration, enabling them to be engaged from beneath
by a portion of the converger 29, as hereinafter described.
The ribbons 20 are moved by the cutter conveyor 48 to and past the
cutter 26. The cutter 26 comprises (FIG. 3) a plurality of
cylindrical sections 73 of substantially the same diameter keyed to
a common drive shaft 75 journaled between two upright plates 77
attached to opposite walls of a frame 79 of the machine. A gear 81
is drivingly secured on the drive shaft 75 and is maintained in
engagement with an idler gear 83 mounted on an idler shaft 85. The
idler shaft 85 is journaled in one of the plates 77 and carries a
sprocket 87 connected by means of a chain 89 to a sprocket 91 keyed
to the spindle 93 of a gear box 94 suitably mounted, by means not
illustrated, on the frame 79 of the machine. A motor (not shown) is
drivingly connected to the gear box 94. Preferably, the motor which
drives the gear box 94 is also drivingly connected to the conveyor
48, either through the gear box 94 or otherwise so that the same
motor drives both the conveyor 48 and the cutter 26, thereby
insuring synchronization between the two.
Each of the cylindrical sections 73 of the cutter 26 carries a
plurality of radially directed blades 95 spaced circumferentially
about the periphery thereof. As may be seen in FIG. 4, the blades
95 are secured in their respective cylindrical sections 73 by means
of mounting blocks 97 which fit in suitable recesses 99 formed in
the surfaces of the sections. The blocks 97 are secured to the
section by means of bolts 101. Each of the recesses 99 has an
inclined wall therein and, upon tightening of each of the bolts the
block 97 associated therewith is forced against the blade. This
wedges the blade against the wall of the recess opposite the
inclined wall and holds the blade securely in place within the
recess.
The circumferential spacing of the outer ends of the blades 95
about their respective cylindrical sections 73 corresponds to the
desired length of the individual cheese slices. In the drawings,
four blades are shown about the circumference of each section, but
it is to be understood that variations are possible within the
scope of the invention. The tips of each of the blades 95 are
sharpened and the motor (not shown) drives the shaft 75 such that
the tangential velocity of the tips equals the linear velocity of
the cheese ribbons 20 moving beneath. At the lower extent of their
arcuate travel, the blades cooperate with the belts 49 of the
cutter conveyor 48 to cut the ribbons transversely to form the
individual cheese slices. Because the blades are moving in the same
direction and at the same speed as the ribbons, there is no
bunching or tearing of the cheese during the cutting process. In
fact, the cheese ribbons are under a slight tension prior to being
cut. This tension is relaxed as the ribbons are cut, permitting a
slight shrinkage of each individual slice and creating a slight gap
103 between each slice and the immediately preceding and succeeding
slices (FIG. 3).
Referring to FIG. 5, it will be observed that the individual slices
of cheese leaving the cutter 26 are in staggered positions, that
is, not directly abreast of each other, for reasons subsequently
explained in connection with the operation of the converger 29.
More specifically, the ribbons are cut so that each transverse cut
of any one ribbon is spaced longitudinally from rather than aligned
with the transverse cuts of an adjacent ribbon. This longitudinal
spacing is approximately equal to the quotient of the distance
between cuts in any one strip divided by the given number of
strips. The slices are aligned in pairs spaced transversely of the
direction of movement, each pair being comprised of one slice from
one of the four lines toward the left, and of one slice from one of
the four lines to the right when considering the slices produced
from eight ribbons. In this manner, two slices are presented for
pickup by the converger at the same time. Thus, the slices shown in
FIG. 5 and designated 22a through 22h are typical of those formed
by a fraction of a revolution of the cutter shaft 75. It will be
seen that slices 22a and 22g are in transverse alignment, as are
slices 22b and 22f, 22c and 22e, and slice 22d and a slice 22h of a
succeeding set. This specific arrangement has been found to be
preferable in that it avoids interference between the slices as
they are picked up by the converger.
The slices 22 are delivered by the cutter conveyor 48 to the
converger 29, the basic function of which is to converge or combine
each set of four adjacent horizontal input lines of cheese slices
28 into a single output line 21 of individual cheese slices. In the
illustrated apparatus, the converger combines two groups of four
input lines into two single output lines, one for each group.
The particular structure of the converger is illustrated in FIGS. 6
through 10. Some elements in these figures are broken away or left
out for clarity.
The converger includes a plurality of cheese-carrying elements or
pickers 105, each of which is adapted to carry an individual cheese
slice 22. In FIGS. 7 and 8, the details of the pickers includes a
pair of projecting prongs 107 having flattened tips or shelves 109
for contacting the underside of the cheese slice which it supports.
The width of the pickers at the prongs is such as will enable the
prongs to fit into the gaps 71 intermediate the belts 49a and
engage the cheese slices from beneath. The prongs extend from a
tubular body 111 of rectangular external and internal cross
section, and may be welded to the body 111 or may be formed
integral therewith in a casting. Plastic has been found to be a
suitable material from which the pickers can be fabricated.
The pickers 105 are supported on a plurality of cross bars 113,
each of which carries two pickers. The cross bars 113 are of
rectangular cross section and extend through the tubular bodies 111
of the pickers. The tubular bodies are free to slide longitudinally
along the cross bars 113 but, because of the rectangular mating
cross sections of the pickers and cross bars, the pickers will turn
when the cross bars are rotated.
Each of the cross bars carries a pivot element 115 and 117,
respectively, at its opposite ends. Basically, the pivot elements
comprise a cylindrical body with a pair of spaced flanges on each
end thereof. The pivot elements 115 are all rotatably mounted
intermediate the links of a traveling conveyor chain 119.
Similarly, the pivot elements 117 are all rotatably mounted
intermediate the links of a traveling conveyor chain 121. (In FIGS.
6-10, parts of the chains 119 and 121 are broken away to show
sprockets 123 and 125, discussed below, by which they are
supported.) The chains are of identical size and the spacing of the
pivot elements 115 and 117 therealong is such that the cross bars
extend between the chains perpendicularly thereof and are evenly
spaced from each other. The cross bars move with the chains and,
because of the pivot elements 115 and 117, are free to rotate with
respect thereto.
In order to guide and drive the two chains 119 and 121
simultaneously, four sprockets 123, 125, 127 and 129 are provided,
each of which have teeth which drivingly engage one of the chains.
Thus, the two sprockets 123 and 127 engage the chain 119, whereas
the two sprockets 125 and 129 engage the chain 117. The sprockets
123 and 125 are mounted on a drive shaft 131 near the opposite ends
thereof, and the sprockets 127 and 129 are mounted on an idler
shaft 133 near its opposite ends. The shafts 131 and 133 are
suitably journalled at their ends in the frame 79. Driving torque
is transmitted to the drive shaft 131 through a drive sprocket or
gear 135 keyed to the shaft near the sprocket 123. The drive
sprocket or gear 135 is drivingly connected to an output shaft of a
gear box (not shown) driven by the motor which also powers the
cutter 26 and cutter conveyor 48. Upon rotation of the drive shaft
131, the sprockets 123 through 129 and the conveyor chains 119 and
121 are simultaneously driven so that the cross bars 113 move
parallel with each other and with the chains, forming a continuous
conveyor for carrying the pickers 105. Two chain tracks 137 (FIGS.
8 and 9) are supported, by means subsequently explained, between
the sprockets 123-129 and serve to support and guide the upper runs
of the chains, as they pass between the sprockets, by engaging the
undersides of the chains.
The position of the pickers 105 is regulated both as to the
orientation of the shelves 109 of the prongs 107 with respect to
the horizontal and as to the position of the pickers on the cross
bars 113 upon which they are slidably mounted. Movement of the
pickers along the cross bars 113 initially places them in position
to engage from beneath the individual slices of cheese delivered by
the cutter conveyor 48 and subsequently causes them to converge the
several input lines 28 of cheese slices into a pair of output lines
21. Control over the orientation of the pickers causes the shelves
109 to lie in a horizontal plane from immediately prior to the
pickup of the cheese slice until after the slice has been removed
from the picker, thereby minimizing shifting movement of the slice
on the shelf.
Referring first to the orientation of the pickers, the pickup of
the cheese slices by the pickers occurs while the pickers are
moving in an arcuate ascending path, i.e., at the point of travel
of the pickers at which the cross bars carrying them are passing
around the sprockets 127 and 129. Normally during such movement,
the flat slice-engaging surface 109 of the prongs 107 would be
inclined relative to the horizontal. However, such a disposition of
the surface would not be conducive to an orderly pickup of the
slices. Accordingly, the pickers are guided in their movement so
that the flat upper surface of the prongs remains generally
horizontal as the picker moves upwardly from beneath the slice and
engages the slice, and until the slice is removed from the surface
109.
In this regard, a cam track or groove 139 in the shape of a closed
loop (FIG. 7) is provided in a vertical plate 141 which is secured
to one wall of the frame 79 of the machine. Each of the pivot
elements 117 of the cross arms 113 has an arm 143 keyed thereto on
the opposite side of the chain 119 from the pickers. The arms
extend inwardly toward the camming groove 139 and terminate
adjacent thereto. Each of the arms carries a cam follower roller
145 which is received in the groove and moves therein as the chain
117 moves about the sprockets 125 and 129. The arms 143, being
keyed to their respective pivot elements 117, control the rotative
orientation of the cross bars 113 according to the contour or
configuration of the groove 139. Due to the mutual rectangular
cross sections of the pickers 105 and the cross bars 113, the
position of the arms 143 will also regulate the rotative
orientation of the prongs 107 and shelves 109 on the pickers with
respect to the horizontal.
The effect of the camming groove 139 on the position of the pickers
105 and, more, particularly, on the shelves 109 thereon may be seen
best in FIG. 7. As viewed in that figure, the movement of the
pickers 105 is clockwise, approaching the slices 22 in an arcuate
path from underneath. The camming groove 139 is shaped such that
the position of the shelves 109 on the pickers will be as shown in
phantom at the left-hand edge of the figure. Just prior to and
following passage of the pickers 105 between the belts 49a of the
cutter conveyor 48, the shelves 109 are maintained in a horizontal
position. Thus, they evenly engage the underside of the cheese
slices and lift them from the conveyor. The shelves are maintained
in a horizontal disposition until they have deposited the cheese
slices on an output conveyor 147 as will be subsequently
described.
In order for the converger to carry away all of the cheese slices
delivered to it from the plurality of input lines which it
services, the pickers are moved at a velocity which is several
times greater than the input velocity of the ribbons 20. The order
of magnitude by which the output velocity is greater than this
input velocity preferably corresponds at least to the number of
ribbons being converged into a single row. In the illustrated
apparatus, four input lines are being converged into a single
output line and, consequently, the pickers 105 travel at a speed
which is about four times that of the ribbons 20. By making the
output velocity at least this magnitude, the slices in the output
line will not overlap but will be spaced to the same degree as when
they are cut. They are therefore easily handled by the wrapping
machine 30. This assumes, of course, that approximately the same
spacing is desired between the slices in the output row as in the
input rows. It may be desirable to effect a greater spacing between
the slices in the output row to facilitate wrapping, in which case
the output velocity would be an even greater multiple of the input
velocity. It would be possible, of course, to accelerate the slices
in two stages through the use of an intermediate conveyor so that
the acceleration imparted by the picker would be less than the
product of the number of ribbons and their input velocity, although
the total acceleration would remain the same. In the illustrated
embodiment, a unit is removed from each row in a predetermined
sequence, such selection being made at a time interval which
approximates the quotient of the time elapsing while one unit
travels a distance equal to its own length divided by the number of
rows of units being condensed into a single row.
Transfer of cheese slices between the cutter conveyor 48 and the
converger pickers 105 could conceivably cause slippage or
disorientation of the cheese slices with respect to each other and
their direction of movement since the pickers are moving at a much
greater speed than the conveyor, and since the change in speed of
the cheese slice occurs over a relatively short interval of time,
necessitating a rapid acceleration of the slice. Where the cheese
slices are subsequently to pass into a wrapping machine, this
misalignment could prevent proper wrapping of the cheese slices.
Furthermore, such misalignment may be severe enough that the cheese
slices could topple into the machinery and become destroyed.
The converger 29 of the present invention avoids this problem by
effecting engagement between the cheese slice and the picker at
that point in the travel of the picker in which it has a horizontal
velocity component which is equal to the speed of the cutter
conveyor and a resultant speed equal to the desired ultimate speed
of the slice. The acceleration of the slice is therefore
essentially entirely vertical, causing the slice to bear down upon
the shelf 109 of the picker but creating no horizontal forces which
could cause the slice to shift on the shelf.
In determining the precise location of this ideal point of
transfer, it will be recalled that the ultimate velocity of the
cheese slices is at least equal to the product of the velocity of
the cheese ribbons and the number of ribbons. This ultimate
velocity has a horizontal component equal to the velocity of the
input conveyors, i.e., the velocity of the ribbons, when the
direction of the ultimate or resultant velocity is at an angle to
the horizontal whose cosine is equal to the ratio of the velocity
of the ribbons to the desired ultimate velocity. Since the
resultant velocity is a tangential velocity as the pickers move in
a curved path at the entry end of the converger, the desired point
is that point at which a tangent to this path is at the
above-mentioned angle to the horizontal. The path, of course, is
the path of the cross bars 113 on which the pickers are supported.
If a slightly greater ultimate velocity is desired, a slightly
greater angle will be used.
EXAMPLE
Four ribbons are delivered to an input conveyor which is moving at
a velocity of 500 in/min. The ribbons are cut into slices which
move at the same velocity. The slices are converged into a single
row of slices moving at a velocity of 2,000 in/min. The ratio of
the initial velocity of the ribbons (500 in/min) to the ultimate
velocity of the slices (2,000 in/min) is 0.250, which is the cosine
of 75.5.degree.. The pickup point, therefore, lies approximately on
a line drawn through the point where a tangent to the arcuate path
of the cross bars is at an angle of 75.5.degree. to the horizontal.
The line drawn through this point is at the complementary angle of
14.5.degree. to the horizontal.
Thus, at the instant each cheese slice is picked off the cutter
conveyor 48 by the pickers 105, the horizontal velocity of the
conveyor and the horizontal velocity of the shelves 109 of the
pickers will be the same. As the pickers complete their arcuate
path and begin moving only horizontally, the horizontal velocity of
the pickers and, hence, the cheese slices carried thereby will have
accelerated from the velocity of the cutter conveyor to the
velocity of the output conveyor 147.
As the pickers 105 move through their arcuate paths to engage and
lift the cheese slices from the input conveyors, they are
maintained in alignment with the gaps 71 between the conveyor belts
49a such that the prongs 107 on the pickers will pass into the
gaps. This alignment is accomplished by a plurality of guides 149
(see FIG. 8) which are mounted on a cylindrical drum 151 coaxial
with the sprockets 127 and 129. The drum 151 is mounted on the
shaft 133 and is spaced from the sprockets 127 and 129 by spacer
bushings 153. Each of the guides 149 includes a pair of spaced
apart rectangular sides 155 which extend radially outwardly from a
web 156 secured to the drum 151. The guides are positioned in a
predetermined pattern about the periphery of the drum in accordance
with the order and position of the respective pickers 105 as they
are returned to the input conveyor end of the converger, as will be
explained subsequently.
In order to effect engagement between the pickers 105 and the
guides 149, each picker is provided with a forwardly extending
appendage 158 (FIGS. 11-14) on which is mounted a cam follower
wheel 157. The spacing of the rectangular sides 155 on the guides
149 is such as to accommodate the cam follower wheel 157 of the
pickers. The underside of each picker is provided in addition with
a downwardly extending appendage 158 which carries a pair of spaced
cam follower wheels 159 mounted for rotation about axes normal to
the axis of the cross bar 113 on which the picker is carried. A the
drum 151 rotates, at the same angular velocity as the sprockets 127
and 129, the guides 149 move with the pickers 105 as the links of
the chains 119 and 121 to which they are coupled are passed around
the sprockets. The walls or sides 155 prevent movement of the
pickers 105 along the cross bars 113 upon which they are slidably
mounted, and thereby proper alignment of the pickers with respect
to the gaps 71 between the conveyor belts 49a is maintained. The
precise manner in which each of the pickers is aligned with the
proper one of the guides 149 on drum 151 as the pickers return from
the output conveyor end of the converger will be explained in
detail subsequently.
The converger includes a system of cams for guiding the pickers 105
from their diverged positions at the cutter conveyor 48 into single
file alignment in the direction of movement. This enables the
pickers to deposit the cheese slices on the output conveyor 147 in
a single line. The convergence cam system includes a pair of cross
bars 161 (FIGS. 7 and 8) which are mounted to extend between
opposite walls of the machine frame 79 by flanges 163. A pair of
mounting brackets 165 are attached to each of the two bars 161
toward the ends thereof and support eight convergence cam tracks
169, each of which consists of a wide metal strip fastened on its
edge to the top surface of the brackets 165. The cam tracks 169 are
received intermediate the cam wheels 159 of the pickers and are
shaped to displace the pickers 105 along the cross bars 113 to
which they are slidably fastened, and to thereby cause the pickers
to converge into a single line moving toward the output conveyor.
As may be seen in both FIGS. 6 and 7, the cam tracks overhang the
brackets 165 toward the drum 151 and approach the periphery of the
drum closely.
As the guides 149 on the drum 151 drop away from the pickers 105 at
the beginning of the horizontal movement of the pickers between the
two ends of the converger, one of the cam wheels 159 on each of the
pickers engages the side of one of the cam tracks 169. The cam
tracks at this end are spread out across the width of the converger
in order to receive pickers from each of the guides 149 on the
drum. As the chains 119 and 121 continue to move the pickers toward
the output conveyor, the convergence cam tracks guide each of the
pickers into alignment with one of two output lines. The heights of
the cam tracks varies, the two middle tracks in each group of four
being higher than the outer two. This is to allow for clearance of
the other of the cam wheels 159, the latter being mounted at
varying levels for selection of the pickers as they are diverged in
their return path, as explained below.
Because of the staggered cut of the cheese slices, as explained
previously in connection with the cutter 26, and because of the
positioning of the pickers and the horizontal acceleration thereof,
the apparatus illustrated converges two groups of four input lines
each of individual cheese slices into two output lines, with each
of the two pickers on one of the cross bars 113 serving a different
output line. The cam wheels 159 on the pickers 105 are spaced from
each other such that, at the sharpest angle of the convergence cam
track, both rollers will contact the cam track and roll against the
surface thereof to prevent binding.
After moving from the input end of the converger 29 at which the
cheese slices are picked up by the pickers 105, the pickers move
toward the output end of the converger where the individual slices
22, which are now moving in two output lines 21, each of which
represents the total slices in four input lines 28, are deposited
upon the output conveyor 147. The output conveyor (FIGS. 6 and 7),
like the cutter conveyor 48, is constructed so as to provide spaced
conveyor sections so as to define gaps 148 which permit the pickers
to pass through the gaps while depositing the slices on the
conveyor, as hereinafter described. The upper level of the output
conveyors is very slightly below that of the highest level of the
shelves 109 of the pickers 105. Thus, as the pickers pass through
the gaps 148 of the output conveyors 147, the cheese slice carried
on each picker moves over the output conveyor, straddling the gap.
As the chains 119 and 121 pass around the sprockets 123 and 125,
the pickers drop through the gap so that each cheese slice becomes
deposited on and entirely supported by the conveyor. The output
conveyor is caused to travel at the speed of the pickers and there
is no change in the velocity of the slices.
In order to maintain the position of the pickers 105 so that they
remain within the gaps of the output conveyors 147 after the
convergence cam tracks 169 terminate, and so that they arrive at a
diverging station in a predetermined position, a pair of flanged
wheels 173 and 175 are provided and are mounted on the drive shaft
131 (FIGS. 6, 7 and 9). The flanged wheels rotate with the shaft
131 and, hence, with the sprockets 123 and 125. Each of the wheels
is in alignment with one of the output lines 21, each wheel
servicing a converged group of four input lines 28. As the pickers
105 approach the periphery of the wheels 173 and 175, the wheel
flanges pass on either side of one of the rollers 159 on the
undersides of the picker. The particular roller which is guided
varies in succeeding pairs of pickers, as explained below, and by
guiding the roller therein between the flanges of the wheel, the
picker 105 is precisely positioned on the cross bar 113 upon which
it is mounted.
Provision is made for maintaining alignment of the pickers with the
flanged wheels after the cam tracks terminate. This is accomplished
by guide rails 177 supported on brackets 179 which, in turn, are
bolted to further brackets 181. The brackets 181 extend from the
previously referred to brackets 165 which support the cam tracks
169, and may be welded to such brackets. As may be seen in FIG. 9,
the rails are positioned to contact opposite ends of the body 111
of each picker 105 to prevent it from moving along the cross bar
113 on which it is secured.
After depositing the cheese slices on the output conveyors, the
pickers are returned to the input conveyors and to their diverged
position in order to once again pick up the incoming lines of
cheese slices. The cams for accomplishing the divergence of the
pickers are supported on a cam support plate 183, which is mounted
to a pair of cross bars 185 by means of four brackets 187, two on
each cross bar. Each of the cross bars 185 is mounted to the frame
79 by flanges 189 and extends between the two walls of the frame at
a location between the sprockets 123-129 driving the chains 119 and
121. The lower portions of the chains between the sprockets are
kept from sagging by two chain tracks 191 (FIG. 8) supported on
brackets 193 attached to the frame 79.
Each successive picker, as it leaves the area of guidance by one of
the wheels 173 and 175, is diverged to a different position with
respect to the input conveyers. The return cam guidance system
provided is designed to select the proper picker for each of
several divergence cam tracks 195. Referring particularly to FIGS.
11 through 14, it may be seen how the apparatus selects each of
four immediately successive pickers to guide same along a different
one of the cam tracks as the pickers leave the guide wheel 173 and
begin their return movement in the direction of the cutter conveyor
48. By comparing the various figures, it will be seen that the two
appendages 158 on the pickers 105 vary in their length. Thus, as
the picker in FIG. 11 leaves the wheel 173, the wheel 159 furthest
to the right will engage the cam track 195d and be diverted along
this cam track. As will be noted in FIG. 10, the forward end of the
track 195c, i.e., the end nearest the output end of the converger,
is located far enough rearwardly of the forward end of the cam
track 195d to avoid interference between the wheel furthest to the
left (FIG. 11) and the track 195c.
The picker which is immediately behind the one illustrated in FIG.
11, shown in FIG. 12, has a sufficiently short right-hand appendage
158 to permit the right-hand wheel 159 thereon to pass under the
cam track 195d. Thus, divergence of the picker of FIG. 12 will not
occur until the right-hand one of the wheels 159 strikes the
surface of the cam track 195c. The cam track 195c projects a
sufficient distance from the support plate 183 to engage the wheel
159 furthest to the right.
In so far as the picker shown in FIG. 13 is concerned, the
appendage 158 is on the left side of the body 111. Furthermore, the
left-hand portion of the appendage is sufficiently short to permit
the wheel 159 thereon to clear the cam track 195a. As a result,
divergence of the picker of FIG. 13 will not occur until the
left-hand wheel 159 strikes the cam track 195b, the latter
projecting a sufficient distance from the support plate 183.
Finally, in the picker shown in FIG. 14, the wheels 159 are of
equal elevation and the left-hand wheel 159 is guided by the cam
track 195a. As a result, when the picker of FIG. 14 leaves the
guide wheel 173, the wheel 159 on the left-hand side will strike
the surface of the cam track 195a to be guided thereby. Location of
the forward end of the track 195b rearwardly of the forward end of
the track 195a prevents interference between the track 195b and the
right-hand roller 159.
Returning now to FIG. 10, it will be seen that the plan
configuration of the cam tracks 195 is such that the pickers will
be guided to four positions spaced along one-half of the axial
length of the drum 151. Upon returning to the drum in these
positions, the guides 149, which are suitably positioned on the
drum, will guide the pickers between the appropriate belts of the
cutter conveyor 48. The cam tracks 195e through 195g are of a
similar configuration to the four cam tracks just described, and
the pickers being guided by the wheel 175 will be returned to these
cam tracks in the same manner as just described.
Referring now more specifically to the construction of the output
conveyor 147, as illustrated in FIGS. 6 and 7, it will be seen that
the conveyor comprises a frame which includes two pair of
horizontally spaced vertically arranged side plates 197. Each plate
carries a stud shaft 199 adjacent its rearward end, with each stud
shaft projecting inwardly toward the opposite plate of the pair.
Each stud shaft 199 has rotatably mounted on it a sprocket 201. In
addition, a shaft (not shown) extends between each pair of plates
forwardly of the shafts 199 and carries a pair of sprockets (not
shown), each of which is aligned with a sprocket of a stud shaft
199. The sprockets carry a chain to which are attached bars 203
which define a flat surface for receiving the cheese slices 28. The
rearward shaft also carries a drive sprocket (not shown) suitably
connected to a power source for driving of the shaft and associated
chain.
Thus, between each pair of plates 197 two bar conveyors 205 are
provided, these conveyors being horizontally spaced a sufficient
distance to permit passage of the pickers therebetween. As the
picker moves downwardly through the gap between the conveyors 205,
the lateral edge portions of the slices which overhang the lateral
edges of the pickers, engage the bar conveyor and are supported
thereby.
In order that the central portion of the slice deposited by the
pickers may also be supported, a plate 197 of each pair carries a
bracket 207 having mounted on it a rearwardly extending arm which
carries at its rearward end a rotatably mounted pulley 209. A
similar pulley 211 is mounted rearwardly of the pulley 209 on a
shaft 213 which carries a sprocket 215 for imparting rotation to
the shaft through a suitable power source. The pulleys 209 and 211
carry an O-ring belt 217 of very narrow diameter which, together
with the arm of the bracket 207, is narrow enough to pass between
the prongs 107 of the pickers 105 as the pickers in turn pass
between the conveyors 205. Thus, the central portion of the slice
is supported by the O-ring belt 217.
To review the operation of the apparatus from the beginning, and in
connection with the formation of a single output line 21 of
individual cheese slices 22, the cheese leaving the chill roll 36
is cut into ribbons by the blades 41. The ribbons of cheese 20 are
collated into a stack by the collator rollers 44. Upon reaching the
decollator rollers 46, the ribbons are peeled off and carried on
the flat cutter conveyor 48 in adjacent horizontal relationship.
The cutter 26 cuts the ribbons transversely to form a plurality of
slices of cheese. These cheese slices are carried in lines,
referred to herein as input lines 28, by the cutter conveyor to the
converger 29.
The cheese slices of four of the input lines are picked up by the
converger 29 and are converged into a single output line which is
moving at a velocity which is four times that of the ribbons 20.
This is accomplished by a plurality of pickers 105 which pick up
cheese slices having a horizontal velocity which is the same as the
velocity of the cutter conveyor 48, accelerate them to the velocity
of the output conveyors 147, and move them into a single line. The
converger then transfers the cheese slices to the output conveyor
147 which carries the cheese on to a wrapping and packaging machine
30. Thus, the four ribbons 20 are formed into four input lines 28
of individual cheese slices 22, and then are converged into a
single output line 21 of individual cheese slices, all
automatically.
It may therefore be seen that the invention provides an improved
method and apparatus for producing an output line of individual
cheese slices from a plurality of adjacent cheese ribbons. The
invention also provides an improved method and apparatus for
converging a plurality of adjacent moving lines of individual
cheese slices into a single output line of individual cheese
slices. The spacing between the cheese slices in the output line is
such as to prevent overlap and the quantity of cheese slices being
conveyed by an output line is the same as the total quantity of the
converged input lines.
Various other embodiments and modifications thereof in addition to
those shown and described herein will be apparent to those skilled
in the art from the foregoing description. For example, it should
be clear that the invention is not limited to the handling of
cheese and may be equally effective in the conversion of strips of
various other materials into a single file row of units. Such other
embodiments and modifications thereof are intended to fall within
the scope of the appended claims.
* * * * *