Variable pitch escapement for article infeed in packaging machine

In a packaging machine the articles to be packaged are handled by escapement means that generate gaps between successive articles in each column. The escapement means includes at least two pin conveyors, each of which is driven at a speed which is controlled whereby to permit varying the pitch distance between the pins of each of these two conveyors in order to accommodate a different number of and differently sized articles. The articles are separated by a take away conveyor driven at a slightly greater speed than the pin conveyors to create gaps between the adjacent rows of articles. Partitions may be fed into these gaps, and other gaps are used to permit entry of a flight bar grouper conveyor that ultimately groups the articles so as to create a desired pack pattern for loading.

BACKGROUND OF THE INVENTION 
The present invention relates to packaging machines of the type adapted to 
handle articles fed continuously by line pressure in a downstream 
direction into the machine where groups of the articles can be mated with 
individual trays. More specifically, the present invention relates to a 
unique escapement means capable of creating gaps between adjacent rows of 
articles as the articles move in columns in a downstream direction. The 
articles are then grouped for delivery into a load station. 
DESCRIPTION OF THE PRIOR ART 
Packaging machines of the type adapted to pack groups of articles in trays 
or the like, where the articles move continuously in a downstream 
direction through a load station, generally include means for grouping the 
articles so that these groups can be loaded on individual trays or cases. 
Such continuous motion high speed tray loading machines must be shut down 
for change-over to loading articles of different size. These shut down 
times interfere with orderly production schedules, and can require rather 
extensive re-working of the complicated grouping devices commonly provided 
in such packaging machines generally. 
SUMMARY OF THE INVENTION 
The general purpose of the present invention is to provide a variable pitch 
escapement and grouping mechanism for the article infeed to such a 
packaging machine wherein the line pressure is controlled by the variable 
pitch escapement and each row of articles is separated from an adjacent 
row as the articles move in columns downstream toward the load station. 
The individual rows so segregated can be conveniently fitted with 
partitions in the gaps therebetween. A more important result however is 
that provision is made for an overrunning flight bar or grouper conveyor 
that compresses any convenient number of segregated article rows to form 
groups of desired size so that the groups can be provided on individual 
trays or in individual packing cases at the load station. 
The present invention accomplishes these objects by providing a packaging 
machine with lane guides for handling columns of generally cylindrical 
upright articles as they advance by line pressure into the upstream end of 
the packaging machine. The escapement means holds back the columns of 
articles and releases the articles row on row at a controlled rate. The 
escapement means includes two congruent pin conveyors, one of which pin 
conveyors has its pins driven at a substantially constant speed somewhat 
slower than the speed of the infeed conveyor 16. The articles slip 
relative to the conveyor chain and their resulting traction against the 
chain cause sufficient line pressure to prevent gaps in the rows while the 
rows are controlled by the escapement. The other of said two pin conveyors 
has its pins driven at a controlled speed that varies cyclically in order 
to match the speed of said first pin conveyor only during movement of all 
the pins along upper runs of these conveyors where the pins are spaced at 
a pitch dimension that is thereby kept within a predetermined range. The 
predetermined pitch dimension range allows the pitch to be varied to 
accommodate articles of different size. In fact, pitch distance can be 
varied to accommodate different numbers of articles so that the range of 
pitch dimensions can be kept within a reasonable range, and nevertheless 
accommodate articles of significantly different diameters. 
Another feature of the present invention relates to the capability for 
varying the lateral spacing between the lane guide to accommodate these 
differently sized articles. The lateral adjustment made to the lane guides 
also achieves corresponding adjustment to the spacing between the pins on 
each of the two pin conveyors. 
Still another feature of the present invention can be attributed to the 
fact that the articles are aligned laterally as they move in columns by 
the pin conveyors, and the pin conveyors achieve separation or gaps 
between adjacent article rows so that partitions can be conveniently 
inserted between certain of these article rows within each of the 
ultimately formed groups of articles to be loaded on a particular tray or 
in a particular packing case. 
Finally, the pin conveyors are driven by motors that are computer 
controlled so that the speed of at least one and preferably both pin 
conveyors can be varied within each cycle. This capability permits the 
pins to remain vertical as they move upwardly between the adjacent 
cylindrical articles and associated lane guides. Each pin conveyor runs on 
an endless chain which moves in a sloped path as the pins move upwardly 
into the spaces between adjacent articles, and also as these pins move out 
of such spaces at the ends of their upper runs. During the return runs of 
at least one of the pin conveyor chains, adjustments are made to the chain 
speed so that the desired pitch distance between the pins can be 
maintained during their active or upper runs. A downstream flight bar 
conveyor system is provided to subsequently group the articles as required 
for loading article groups of desired pack pattern on trays or in packing 
cases.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Turning now to the drawings in greater detail, FIG. 1 shows a portion of a 
packaging machine that is suitable for use in packaging articles fed 
continuously by line pressure from an infeed conveyor 16 in a downstream 
direction, as indicated by the arrow 10, toward the load station of the 
machine where groups of the articles, such as suggested at 12, are mated 
with an upwardly open tray or packing case (not shown). 
These grouped articles 12,12 are advanced on a dead plate 45 by the flight 
bar conveyor 14 and grouped in a pack pattern for a particular tray 
configuration. 
The infeed conveyor 16 operates continuously at a speed that advances these 
articles between lane guides 46,46 to provide one or more columns of 
articles as shown in FIG. 2. The articles are aligned in laterally 
extending rows by operation of an escapement mechanism to be described. 
Only one column of articles is shown in FIG. 1 to present in schematic 
fashion the operation of the escapement mechanism. Two pin conveyor chains 
18,19 operate two sets of pins 20 and 22 so that upper runs of both 
conveyor chains travel in a downstream direction at a speed somewhat 
slower than the speed of the overrunning infeed conveyor 16. The pins 20 
on one conveyor 18 slow the advancing articles to the speed of the pin 
conveyor 18. The second pin conveyor 19 arranged in congruent fashion with 
the first conveyor 18 carries a second set of pins 22, one of which is 
shown between adjacent articles at the downstream end of the four adjacent 
articles (1,2,3,4) and dictates a particular pitch distance X defined by 
the diameter of each article multiplied by the number (four) of such 
articles. 
Riding strips, or dead plate rails 24 are provided for each column of 
articles between the pins, for supporting the articles as they move 
through the escapement pin conveyors 18,19 that drive the pins 20 and 22 
respectively. 
A higher speed take away conveyor 30 is provided downstream of the riding 
strips 24, and serves to create a gap between the adjacent rows of 
articles so as to provide a number of rows (1, 2, 3 and 4 in FIG. 1) on 
this take away conveyor 30. The gaps between the adjacent articles are 
utilized to insert partitions 32,32 from a magazine 34. Each partition is 
driven downwardly into a gap on the fly by suitable partition inserting 
means such as indicated generally at 35 in FIG. 1. 
Since the groups 12,12 of articles to be formed for mating with the trays 
at the load station (not shown) have four rows of articles that comprise 
the group, means is provided for introducing a flight bar 40 of the flight 
bar conveyor 14 into the gap between article 1 and the next following 
article A that is pushed along by one or the other of pins 20 and 22 
associated with the escapement device. Thus, the flight bars 40 and 42 are 
provided one on either side of a prospective group of articles to be 
packaged. Further downstream a flight bar 43 moves the four rows of 
articles (1, 2, 3 and 4) downstream to the load station (not shown). The 
flight bar 42 of conveyor 30 moves the next group 12 across a dead plate 
45 where the flight bar 42 serves to compact or bring together the four 
rows of articles (1, 2, 3 and 4) so as to form an appropriately sized 
group for handling at the load station. The flight bar conveyor 14 
performs the grouping function required for creating the desired pack 
pattern. 
FIG. 2 is a top plan view of the schematically illustrated apparatus of 
FIG. 1, and shows four laterally aligned columns of articles being handled 
by the pins of the escapement pin conveyors described above. Laterally 
spaced lane guides 46,46 are provided over the infeed conveyor 16, and 
along the entire length of the riding strip 24 associated with these pin 
conveyors 18,19 and their associated pins 20 and 22. 
Still with reference to FIG. 2, the pack pattern or grouping of articles in 
the rows (1, 2, 3 and 4) is carried out by providing the take away 
conveyor 30 in the form of a belt that moves each row of article in turn 
away from the endmost row of articles A on the riding strips 24 associated 
with the pin conveyors 20 and 22. This take away conveyor 30 preferably 
comprises a series of laterally extending slats as shown, and it is a 
feature of the present invention that the upstream end of the conveyor 30 
will accommodate the flight bars 40,42,43 as each flight bar moves 
upwardly over the top of the take away conveyor 30. As so constructed and 
arranged the flight bar 42 ultimately contacts the upstream row 1 moving 
it into contact with the next row 2 and finally into contact with the 
leading row 4 so as to form the desired pack pattern or group as described 
previously. 
It is an important feature of the present invention that gaps are formed 
between successive rows of article on the take away conveyor 30, and as a 
result of this capability the pitch distance X between the pins 20 and 22 
of the respective pin conveyors need be varied only slightly to 
accommodate articles of quite different diameter. 
Referring now to FIG. 3, it will apparent that the pin conveyor escapement 
device is capable of accommodating three rows of articles (1, 2 and 3), 
which articles are of somewhat greater diameter than the articles referred 
to previously by reference to FIGS. (1 and 2). The articles of FIG. 3 can 
be grouped in any convenient number, as for example three rows as 
illustrated at 12a in FIG. 3. Note that the take away conveyor 30 operates 
at a slightly greater speed than that of the escapement pin conveyors with 
the result that gaps are created between the adjacent rows on the take 
away conveyor 30. The over running flight bar conveyor 14 will cooperate 
with the take away conveyor 30 and ultimately compress the rows of 
articles on the dead plate 45 in groups of appropriate pack pattern size. 
FIG. 4 illustrates the same apparatus as depicted in FIG. 3 but with even 
larger diameter articles. The pitch distance X in the case of such large 
articles can be conveniently adjusted to accommodate two such articles 
rather than three or four as described above with reference to FIGS. 1 and 
3. FIG. 4 also illustrates the gaps formed between the adjacent rows of 
articles (1 and 2) and the gap provided for the flight bar 40 which will 
ultimately compress the rows (1 and 2) for purposes of packing the 
articles at the load station in groups as suggested at 12b in FIG. 4. 
Turning now to a more detailed description of the apparatus referred to 
schematically in FIGS. 1-4, FIGS. 5-8 inclusively illustrate in detail the 
escapement pin conveyor configuration that cooperates with the take away 
conveyor 30 and the flight bar conveyor 14. FIG. 5 shows the articles 
entering by line pressure between lane guides 46 onto the upstream end of 
the riding strips 24. FIG. 6 shows this riding strip 24 as comprising a 
plurality of longitudinally extending pairs of rails 24,24 each of which 
is supported from one of the lane guides 46 by laterally extending posts 
50,50. These posts are provided at adjacent upstream and downstream ends 
of the riding strips 24, and are supported directly from the lane guides 
46. As a result of this construction, lateral adjustment of the lane 
guides 46,46 to accommodate articles of different diameter also achieves 
adjusting movement of the riding strips 24. As shown in FIG. 6 the lane 
guides 46 are supported from threaded cross shafts 52,52 in conventional 
fashion. The ends of each cross shaft 52,52 are supported in upright 
stanchions as best shown in FIG. 5 at 54,54 and the threaded nuts 56,56 
allow horizontal or lateral clamping of the lane guides in a range of 
positions such that the spacing between them can be varied to accommodate 
articles of different diameter. 
The outside lane guides are located against a stop structure illustrated 
generally at 58. A vertically extending post is provided in the frame of 
the machine to support a laterally extending stop guide 60. A stop nut 62 
may be provided on the threaded rod 52 generally opposite the threaded 
hand nut 56 in order to define the maximum lateral spacing accommodated in 
the machine for a particular size and number of columns of articles. 
Still with reference to FIG. 7, the longitudinally extending riding strips 
24,24 are shown supported on the posts 50. The upright stanchions 54,54 
that carry the threaded cross shafts 52 are supported at the lower ends in 
channel shaped side frame members 64,64. The side frame members 64,64 are 
channel shaped and define inwardly open cavities that support the first 
and second pin conveyor chains. These pin conveyor chains are arranged in 
sets or pairs as shown generally at 18,18 and 19,19. Each conveyor chain 
set is independently driven by an associated motor M1 and M2 respectively. 
A drive sprocket 66 is associated with the motor M1 and the drive sprocket 
68 being associated with the other motor M2 for purposes of driving these 
pin conveyor chain sets. Thus, each pin conveyor comprises a set of 
laterally spaced chains, and it is a feature of the present invention that 
these laterally spaced chains are driven at different speeds over 
congruent paths so that the pins associated with each pin conveyor can be 
independently driven. This feature allows the pitch distance X referred to 
previously to be conveniently varied so that the pins associated with each 
pin conveyor can travel at substantially the same speed during their 
active or upper runs where they are received between the adjacent rows of 
articles. Any make up in speed is accommodated by the return run of the 
pin conveyor chains illustrated at the lower portion of FIG. 8, for 
example. The motors M1 and M2 are preferably motors driven by a 
programmable computer represented schematically by controllers C2 and C1 
as shown in FIG. 7. These controllers C2 and C1 associated with the motors 
M1 and M2 respectively permit the speed of both motors to be repeatably 
controllable, preferably by a programmable computer in accordance with 
well known techniques. Thus, each pin conveyor 18 and 19 and its 
associated pins 20 and 22 can be driven at individually controlled speeds. 
Preferably, each one of these pin conveyors is kept at constant horizontal 
speed while it moves up the ramp 70 of the cam path along the upper flat 
section and down the ramp 72. The motors make speed corrections, during 
the pin travel up ramp 70 and down ramp 72, such that the horizontal speed 
remains constant. FIG. 8 also shows the camming mechanism that maintains 
the vertical orientation for the pins 20 and 22 as the pins move upwardly 
along the ramp 70 into the space provided between the containers, and 
subsequently move downwardly out of that space in the ramp area 72. The 
term "constant" speed provided for at least one of the pin conveyors is 
intended to convey the concept that the horizontal component of motion of 
the pins 20 and 22 in the ramp areas 70 and 72 will correspond very 
closely to the linear speed of the pins as they travel in parallel along 
the same path as the articles on the riding strips 24,24 as described 
previously. Thus, the entry point at which the pins penetrate the plane 
defined by these riding strips 24 can be varied in time to accommodate 
articles of different size and different number, all as referred to 
previously with reference to FIGS. 1-4 inclusively. 
It is an important feature of the present invention that the pins are 
themselves arranged in pairs within each pin conveyor chain circuit, and 
as best shown in FIG. 7 each pair of pins is provided one on either side 
of a lane guide 46. These paired pins are provided on blocks that are 
slidably supported on pin bars 75,75 associated with one or the other of 
the two pin conveyor chains. Each block is slotted for receiving a lane 
guide to couple them for movement with one another. As so constructed and 
arranged lateral adjustments to the locations for lane guides 46,46, to 
accommodate articles of different size, will also achieve corresponding 
adjustment between the respective pairs of pins. These pins are slidably 
mounted on the pin bars 75,75 of each of the two pin conveyor systems for 
this purpose. 
Turning next to a more detailed description of the take away belt conveyor 
30 and the associated flight bar conveyor 14, FIG. 5 illustrates the belt 
conveyor 30 as comprising a plurality of laterally extending plates, and 
shows the upper run or path of this conveyor 30 as common with a portion 
of the path of the flight bar conveyor 14. Note that the flight bar 40 
follows the upper run of the take away conveyor 30 for at least a short 
distance adjacent the upstream end thereof, after which it will ramp 
upwardly as illustrated at 15 in FIG. 5. It is this upward ramp on the 
flight bar conveyor 14 that moves the flight bar 40 into a gap between 
adjacent article rows as provided for this purpose. Other gaps provided 
for by the take away conveyor 30 may be fitted with partitions as shown in 
FIG. 5, each partition being indicated generally at 32 in this view. The 
mechanism for inserting the partitions 32 preferably operated in 
synchronism with the flight bar conveyor 14. A motor M3 drives the flight 
bar conveyor 14 and the partitions are fed from the magazine 34 containing 
a plurality of such partitions by conventional means, such as illustrated 
schematically at 35 in FIG. 5. 
The flight bar conveyor 14 has its flights 40 and 42 etc. so spaced that as 
the articles are moved off the belt conveyor 30 onto the dead plate 45 
they are compressed into predetermined groups (in this case each column 
has three articles for example). Thus, escapement means of the present 
invention combined with this grouping feature permits pack patterns of 
various configurations to be achieved.