Note: Descriptions are shown in the official language in which they were submitted.
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Title of the Invention
RANDOM AUTOMATIC CASE SEALER
Field of the Invention
This invention relates to box or case sealers for closing the open ends
of cardboard boxes or cartons.
Background of the Invention
In the packaging industry, many products are packed in cardboard
boxes or cartons for shipping. Often, one end of the box, namely the bottom,
is sealed shut before the box is filled, and after the box is filled, the open
top
end of the box usually has end and side flaps that are folded inwardly and
downwardly. The box can be sealed by applying glue to the inside of the
mating surfaces of the folded flaps prior to them being folded shut, or by
applying tape to the outside of the flaps after they have been folded shut.
In many cases, the boxes are uniform in size, so providing apparatus
that will fold the flaps and apply adhesive or tape thereto is not
particularly
difficult to do. The apparatus can be adjusted to suit the known width and the
height of the boxes and there is usually no problem running the boxes
through the case sealer once it has been adjusted properly.
However, sometimes the boxes are of different sizes coming down the
same conveyor line. In these instances, a random case sealer is required,
wherein the apparatus for folding the box flaps and applying adhesive or tape
thereto adjusts automatically to suit the size of the box.
A difficulty with the prior art case sealers is that there are limits as to
the length, width or height of the boxes that they can seal. The box end flaps
usually are folded down first, and then the side flaps. It becomes a timing
problem to coordinate the various operations required, and this also affects
or
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is affected by the speed of travel of boxes through the case sealer.
Summary of the Invention
In the present invention, boxes having a wide range of the length
measurement can be accommodated by having a longitudinally movable flap
closer for the trailing end flap of the box.
According to the invention, there is provided a case sealer comprising a
frame having a longitudinal axis and including an entrance conveyor for
moving boxes entering the case sealer along the axis. A pair of longitudinal,
spaced-apart lateral conveyors is located to receive boxes from the entrance
conveyor. A floating head is spaced above the lateral conveyors. Means are
provided for raising and lowering the floating head to suit the height of the
box. The floating head includes an upwardly inclined entrance ramp adapted
to engage and fold inwardly a forward end flap on a box, and a pivoting arm
assembly including a pivot arm pivotable downwardly after the box passes
thereunder to fold inwardly a rearward end flap on the box. A boom extends
toward the entrance conveyor and has a distal end. The pivot arm assembly
is slidably mounted on the boom. Means are provided for sliding the pivoting
arm assembly along the boom to accommodate and close the end flaps of
boxes of varying length. The floating head further includes diverging side
bars for engaging and folding inwardly side flaps on the box after the
rearward end flap has been folded inwardly. Also, a seal dispensing platform
is located downstream from the floating head. The seal dispensing platform
includes holding means for holding the box flaps shut and is adapted to mount
a seal dispenser centrally thereon for sealing the box flaps shut.
Brief Description of the Drawings
Preferred embodiments of the invention will now be described, by way
of example, with reference to the accompanying drawings, in which:
Fig. 1 is a side elevational view of a preferred embodiment of a case
sealer according to the present invention;
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Fig. 2 is a plan view of the low friction conveyor used in the case sealer
of Fig.l;
Fig. 3 is a plan view of the lateral conveyors and means for linking
them together in the case sealer of Figs. 1 and 2;
Fig. 4 is an elevational view similar to Fig. 1, but with components
removed for the purposes of clarity, illustrating the operation of the
pivoting
arm assembly;
Fig. 5 is an elevational view similar to Fig. 4, but with still further
components removed for the purposes of clarity, and showing another
1o embodiment of the height measuring proximity sensors; and
Fig. 6 is a plan view of the case sealer of Fig. 1 with components
removed for the purposes of clarity, and showing another embodiment of the
width sensors.
Detailed Description of the Preferred Embodiments
Referring to the drawings, a preferred embodiment of a case sealer
according to the present invention is generally indicated in the drawings by
reference numeral 10. Case sealer 10 includes a frame 12 mounted on
castors 14, so that the case sealer is easily transportable or movable from
one
packaging line to another. Retractable feet (not shown) may be threadably
2o mounted in frame 12 to engage the floor and make case sealer stationary, if
desired. Alternatively, casters 14 can be of the locking type, for the same
purpose. Frame 12 has a longitudinal axis 18 (see Fig. 2) which indicates the
direction in which boxes or cartons or cases travel to be closed and sealed
shut in case sealer 10.
Case sealer 10 is normally located adjacent to a packaging line (not
shown) to close and seal, one at a time, filled boxes received from such a
packaging line. However, boxes or cartons could be manually placed on case
sealer 10 if desired. Where the cases are received from a packaging line, a
gate mechanism 20 can be provided to space the cases apart prior to being
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closed and sealed, as will be described further below. However, the gate
mechanism could be provided on the end of the packaging line rather than on
case sealer 10, if desired.
Case sealer 10 includes a low friction conveyor 22 which has a plurality
of spaced-apart, transverse, free-wheeling rollers 24, although any other type
of low friction conveyor could be used in case sealer 10. Rollers 24 support
the boxes thereon to be sealed in case sealer 10.
Boxes that are ready to enter case sealer 10 are normally held back by
the gate mechanism 20. When it is desired that the first box on a packaging
line enter case sealer 10, gate mechanism 20 is lowered and the packaging
line conveyor feeds a box to case sealer 10 causing the first box to be moved
on to an entrance portion 50 of conveyor 22. When the box to be sealed
enters entrance portion 50, an entry sensor or a limit switch 56 opens to
sense that the front end of the box has passed that point, and a pair of
longitudinal, laterally spaced-apart, first lateral conveyors 58 and 60, move
inwardly to contact the box entering case sealer 10 and move it along axis 18.
Limit switch 56 is an entry sensor means, and it could be any type of
proximity sensor other than a limit switch per se. Lateral conveyors 58, 60
move at a constant speed, so a proximity sensor could be used on one of the
drive sprockets for lateral conveyors 58, 60 to measure the length of the
boxes, as will be described further below.
Referring next to Figs. 3 and 4, first lateral conveyors 58 and 60 are
slidably mounted on transverse shafts 62 and 64 for inward and outward
movement to adjust for the width of a box being sealed in case sealer 10.
Lateral conveyors 58 and 60 are linked together for equal movement inwardly
and outwardly to match the width of the box passing therethrough. The
linking means includes a continuous belt 65 having a pair of belt portions 66
and 68 (see Fig. 3). Each belt portion has one respective end 70, 72 attached
to the frame of lateral conveyor 60 at a fixed mount 74, and a second
opposed respective end 76, 78 attached to the frame of lateral conveyor 58 at
a fixed mount 80. Sheaves 82 and 84 are rotatably mounted in frame 12, so
that the belt portion 66 passes around sheave 82 and belt portion 68 passes
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around sheave 84, and as a result, when lateral conveyor 60 moves outwardly
away from the longitudinal center line 18 of case sealer 10, belt portion 66
acting through and pulling on fixed mount 80 also causes lateral conveyor 58
to move outwardly away from the longitudinal center line of case sealer 10.
Similarly, when lateral conveyor 60 moves inwardly towards the center line 18
of case sealer 10, belt portion 68 acting through and pulling on fixed mount
80 also causes lateral conveyor 58 to move inwardly towards the center line
of the case sealer. Lateral conveyor 60 is moved inwardly and outwardly by a
pneumatic cylinder 86 mounted in frame 12 and acting through a spring
1o mount 88 attached to the frame of lateral conveyor 60. Spring mount 88 is
simply a spring or other resilient member connected between the piston of
pneumatic cylinder 86 and the frame of lateral conveyor 60. Spring mount 88
provides some flexibility for the relative positioning of lateral conveyors 58
and 60 to accommodate some non-uniformity in the width of the boxes being
sealed in case sealer 10. The belt portions 66 and 68 pass around sheaves 82
and 84 in a U-shaped fashion. Chains and sprockets could be used in place of
belts and sheaves. Other devices, such as racks and a pinion could also be
used to link the lateral conveyors together, so that outward and inward
movement of one lateral conveyor causes respective equal outward and
2o inward movement of the other lateral conveyor. Again, some types of
resilient connection, such as spring mount 88 would be used to prevent
crushing of the boxes, yet providing sufficient frictional force by the
lateral
conveyors 58, 62 against the boxes to move the boxes through case sealer
10.
The normal starting position of lateral conveyors 58, 60 is in the
outermost position, as seen in Fig. 3. When an incoming box hits entry
sensor 56, cylinder 86 causes lateral conveyors 58, 60 to move inwardly to
contact the box. Lateral conveyors 58 and 60 have respective conveyor belts
90 and 92 to move a box therebetween. If a box travelling between lateral
3o conveyors 58 and 60 is off center, it will hit one of the lateral conveyor
belts
90 and 92 first, and this conveyor belt will move the box over toward the
center until it contacts the other of the lateral conveyor belts, and thus be
centered.
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Lateral conveyors 58 and 60 also have centering sensors 96 and 98
mounted just above their respective conveyor belts 90 and 92. Centering
sensors 96 and 98 are pivotably mounted bars that actuate limit switches
behind them. When a box hits one of the centering sensors 96 or 98, the
sensor retracts opening its limit switch, but nothing happens until the box is
moved over toward the center of the case sealer, and then it hits the other
centering sensor. When both the centering sensors 96 and 98 are engaged by
the box, the box is centered. The respective limit switches in sensors 96 and
98 are connected in parallel and when both switches are opened, this causes
1o the lateral conveyors 58, 60 to stop moving inwardly. This also causes a
signal to be recorded by a programmable logic controller (not shown) that
controls the operation of case sealer 10.
Lateral conveyors 58, 60 then move the box along in case sealer 10.
The speed of lateral conveyors 58, 60 is faster than the speed of the
packaging line conveyor that feeds the boxes into case sealer 10, so a gap
opens up between a box that has already entered lateral conveyors 58, 60
and the next following box. When the lower back lateral edge of the box
passes entry sensor 56, gate 20 is raised to hold back the next door until the
box presently between lateral conveyors 58, 60 clears those lateral conveyors
and they open up again, as described below.
As mentioned above, the length of the boxes entering lateral conveyors
58, 60 can be measured using signals from entry sensor 56, but the box
length could also be measured using a proximity sensor 91 (see Fig. 3).
Sensor 91 is of the inductive type that counts the teeth on one of the
sprockets 34 that drives lateral conveyors 58, 60. When a front vertical
corner of the box hits a limit switch or sensor 93, which is similar to the
centering sensors 96 and 98, proximity sensor 91 starts counting sprocket
teeth, and when the rear vertical corner of the box passes sensor 93,
proximity sensor 91 stops counting teeth. The number of teeth information is
sent to the logic controller controlling case sealer 10 and the controller
calculates and stores the length of the box information.
Referring next to Figs. 5 and 6, when a box enters case sealer 10 and
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hits or activates entry sensor 56, a horizontal proximity sensor 100 and a
vertical proximity sensor 102 are activated. These proximity sensors are also
of the inductive type that count teeth, but on stationary strips 117 and 119
mounted on frame 12. Proximity sensor 100 has a pick-up head 101 mounted
on lateral conveyor 58, and sensor 102 has a pick-up head 103 slidably
mounted on an upright post 105.
Head 101 moves with the conveyor 58 so that the proximity sensor 100
can count the teeth on the strip 117. The sensor 100 starts to count the teeth
on the strip 117 to determine the width of the box when the entry sensor 56
1o senses the box entering the sealer 10. This sensor 100 will stop counting
teeth when conveyors 58 and 60 engage a box and are stopped. In other
words, when the sensors 96 and 98 contact the box, the sensor 100 stops
counting and the number of teeth signal is received by the case sealer logic
controller.
Head 103 is moved vertically by a cylinder 99 activated by the case
sealer logic controller when the entry sensor 56 senses a box entering case
sealer 10. Head 103 also includes a photo eye 115 which senses the top edge
of the box side flaps and stops the sensor 102 from counting teeth on toothed
strip 119. Proximity sensors 100 and 102 send signals to the logic controller
controlling case sealer 10 based on the number of teeth counted, and these
signals are used to measure or calculate the width and height of the box
entering lateral conveyors 58, 60. The height includes the upright box side
flaps, and since the width of these flaps is one-half the width of the box,
the
height of the box with flaps closed can easily be calculated based on this
ratio.
The area of case sealer 10 including lateral conveyors 58, 60 and proximity
sensors 100 and 102 is called the measuring stage 25 (see also Figure 1) of
case sealer 10, because its primary function is to measure the height and
width of the boxes as they enter case sealer 10. Entry sensor 56 and cylinder
86, together with linking belts 65, centering sensors 96, 98 and proximity
sensor 100, constitute width sensing and actuation means in the preferred
embodiment.
As the box continues to advance in case sealer 10, the box reaches
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another sensor point or limit switch 104 (see Fig. 1) causing the controller
to
close a pair of longitudinal, spaced-apart, second lateral conveyors 107 and
109 that contact the box, and after that, lateral conveyors 58, 60 are opened
to be returned to the home position and be ready to receive the next box.
The second lateral conveyors 107 and 109 are linked together and moved by
a cylinder 85 (see Fig. 3) in the same way as conveyors 58 and 60, and they
continue at the same speed as lateral conveyors 58 and 60 to move the box
through case sealer 10 until the leading top flap of the box engages an
upwardly inclined entry ramp 106 (see Fig. 1) mounted in a first floating head
108 spaced above the lateral conveyors 107 and 109.
Floating head 108 includes a transverse member (not shown) attached
at its opposed distal ends to slides mounted for vertical sliding movement on
shafts in towers 134. Cylinders 112 mounted in towers 134 are connected to
the slides to move the floating head 108 up and down, as described further
below. Towers 134 further include counterweight devices 136 attached to the
slides to offset the weight of floating head 108. Counterweight devices 136
could be gravitational devices or coil spring type devices, as desired. The
area of case sealer 10 including lateral conveyors 107, 109 and floating head
108 is called the flap folding stage 125 of case sealer 10, because its
primary
function is to fold down the flaps of the boxes.
Prior to the leading top flap of the box hitting entry ramp 106 of
floating head 108, the logic controller controlling case sealer 10 actuates
pneumatic cylinder 112 to raise or lower floating head 108 upwardly or
downwardly to a desired height to fold down the leading end flap of the box.
This height is calculated based on the height and width measurements
provided by proximity sensors 102 and 100 in measuring stage 25. Actually,
it is about 5 percent higher, in case the box side flaps are not perfectly
vertical.
In order to determine in which vertical direction to move floating head
108, the present position of floating head must be known. Referring to Fig. 5,
this is determined by a proximity sensor 94 mounted on floating head 108.
Sensor 94 counts teeth on another vertical toothed strip 95, and sends this
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information to the logic controller controlling case sealer 10. The logic
controller can then determine if floating head 108 is high or low and move it
to the desired height for the box located between lateral conveyors 107, 109.
As the box advances further between lateral conveyors 107, 109 and
the leading top flap of the box has started to be folded down, upwardly and
outwardly disposed side bars 114 and 116 (see Figs 1, 4 and 6) engage the
box side flaps and fold them inwardly. Before the box side flaps are folded
down, however, the trailing end flap of the box is folded downwardly by a
pivot arm 118 actuated by another pneumatic cylinder 120. Pivot arm 118 is
activated when the box hits another sensor point or limit switch 111.
Pivot arm 118 and pneumatic cylinder 120 are part of a pivot arm
assembly 122 slidably mounted in a telescopic boom 124 mounted in floating
head 108. Pivot arm assembly 122 is moved along boom 124 by another
pneumatic cylinder 126 to accommodate and close the trailing end flaps of
boxes of varying lengths up to about 60 inches or even longer simply by
making boom 124 and the lateral conveyors longer, as required.
Since the length of the box is preferably determined by proximity
sensor 91 and limit switch or sensor 93 opening and closing, as soon as the
trailing end of the box passes lateral conveyors 58, 60 based on this length
measurement, the logic controller controlling case sealer 10 can open gate 20
to allow the next box to move into measuring stage 25.
As the first box continues to advance in case sealer 10, the box reaches
another sensor point or limit switch 137 (see Fig. 1) causing the controller
to
close a pair of longitudinal, spaced-apart, third lateral conveyors 140 and
141,
and thereafter to open second lateral conveyors 107, 109. The third lateral
conveyors 140 and 141 are linked together and moved by a cylinder 87 (see
Fig. 3) in the same way as second lateral conveyors 107, 109 and they
continue at the same speed as second lateral conveyors 107, 109 to move the
box through case sealer 10.
As the box passes out through the lateral conveyors 107, 109 and while
the box top flaps are still being held down by floating head 108, the top,
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leading horizontal edge of the box engages an entry ramp 138 (see Fig. 1)
mounted in a second floating head 142. Floating head 142 is similar to
floating head 108 in that it has a transverse member (not shown) having
opposed ends attached to slides slidably mounted on shafts in towers 146
with pneumatic cylinders 148 to move the floating head up or down to match
the height of the boxes entering lateral conveyors 140, 141. Counterweight
devices 150 offset the weight of the floating head 142. Floating head 142 has
a seal dispensing platform 158 on which is mounted a tape head 160 through
spring mounts 159 to provide some flexibility for the relative positioning of
floating head 142 and to accommodate some non-uniformity in the height of
the boxes (up to 5 centimetres) such as may be caused by overfilling, for
example. Sensor point or limit switch 137 sends a signal to logic controller
controlling case sealer 10 to activate cylinder 148 through an appropriate
actuator valve device to raise and lower second floating head 142 to the
desired height of the box as determined in measuring stage 25. This height is
about 5 percent lower than the height at which first floating head 108 was
set, so it is pretty well just above the height of the box with the flaps
folded
down.
In order to determine in which vertical direction to move second
floating head 142, the present position of floating head 142 must be known.
Referring again to Fig. 5, this is determined by a proximity sensor 161
mounted on floating head 142. Sensor 161 counts the teeth on another
vertical toothed strip 163, and sends this information to the logic controller
controlling case sealer 10. The logic controller can then determine if
floating
head 142 is high or low and move it to the desired height for the box located
between lateral conveyors 140, 141.
If desired, floating head 142 can be raised a bit higher than the
measured height of the box, and it can then be moved back down a bit until a
proximity sensor or limit switch 113 engages the box. This determines the
exact height of the box. In this way, floating head 142 rises to the desired
height, even if the box is over filled.
If desired, the logic controller controlling case sealer 10, could be
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programmed to reset or return floating heads 108 and 142 to their highest or
home positions after the boxes clear the respective flap folding and sealing
stages, to ensure that the floating heads are precisely set at the desired
height.
When the box passes under seal dispensing platform 158 and the rear
corner of the box passes another sensor point or limit switch 162, the third
lateral conveyors 140, 141 move outwardly. The area of case sealer 10
including lateral conveyors 140, 141 and the floating head 142 is called the
sealing stage 225, because its primary function is to seal the flaps of the
boxes.
If desired, floating heads 108 and 142 could be combined into a single
floating head by attaching second head 142 to first floating head 108. The
advantage of using separate floating heads, however, is that as soon as a box
is picked up by lateral conveyors 140, 141 and the box has cleared floating
head 108, the lateral conveyors 107, 109 and first floating head 108 can be
reset to receive the next box, thus proving faster operation for case sealer
10.
As seen best in Figs. 1 and 3, lateral conveyors 58, 60; 107, 109 and
140, 141 are driven by a motor 26 and gear box 28 driving a series of
sprockets 34 and drive chains 30. All of the lateral conveyors preferably
operate at the same speed.
Referring again to Fig. 4, the longitudinal distance between sensor 56
and sensor 104 is indicated as "A". The longitudinal distance between sensor
104 and sensor 137 is indicated as "B", and the longitudinal distance between
sensor 137 and sensor 162 is indicated as ~~C". Distance °A" is greater
than
distance "B", which in turn is greater than distance "C". This ensures that
any
given box will move out of its respective one of the measuring stage 25, flap
folding stage 125 or sealing stage 225, before the box next behind it enters
that stage. Alternatively, lateral conveyors 140, 141 could be made to
operate at a higher speed than lateral conveyors 107, 109 (say 20 percent
faster), and lateral conveyors 107, 109 could operate at a faster speed than
lateral conveyors 58, 60 to accomplish the same thing. If differential speeds
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are used to separate the boxes, however, the preceding set of lateral
conveyors should open immediately after the succeeding set of lateral
conveyors picks up the box, or there would be frictional scraping of the sides
of the box by the two sets of lateral conveyors in contact with the box.
In the operation of case sealer 10, the case sealer can be made to
operate in several different modes as selected by a control box (not shown)
containing the programmable logic controller for case sealer 10. Where the
boxes are all of the same height, width and length, after the first box enters
measuring stage 25, the height and width of all the boxes being sealed are
1o known, so lateral conveyors 58, 60; 107, 109 and 140, 141 and the height of
floating heads 108 and 142 can be set and not moved thereafter. Gate 20 is
used to allow the boxes to be separated by a space of about 15 inches to
allow the box rear flaps to be folded down by pivot arm 118. A box can go on
to have its flaps folded down while a box behind it is entering the measuring
stage 25. Similarly, a box can be sealed by the floating sealing head 142
while another box is entering lateral conveyors 107 and 109 to have its flaps
folded down by floating head 108. Once a box enters case sealer 10, it moves
continuously or non-stop until it exits the case sealer.
In a second mode of operation where the height and width of the boxes
are the same but the lengths of the boxes vary and exceed a length of about
24 inches, the cylinder 126 moves the pivot arm assembly 122 out to the end
of boom 124, and as soon as the rear end of the box is sensed passing limit
switch 56, cylinder 126 retracts the pivot arm assembly 122, so that pivot
arm 118 travels along at the same speed as the box. As the box hits sensor
point 111, and just prior to the box side flaps being folded down on top of
the
box front flap by side bars 114, 116, pivot arm 118 comes down to close the
back flap of the box. Again, in this mode of operation, since the height and
width of the boxes are known after the first box enters the measuring stage
25, lateral conveyors 58, 60; 107, 109 and 140, 141 and the height of
floating heads 108 and 142 can be set and not moved thereafter.
In a third mode of operation where the boxes vary in length, width and
height between about 20 and 60 centimetres, the pivot arm assembly 122
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stays in its inward or retracted position. The gate mechanism 20 is not
lowered to let the next box enter the case sealer until the rear end of the
previous box clears lateral conveyors 58, 60. Limit switch 111 is used to
activate pivot arm 118.
In a fourth mode of operation, where the boxes vary in width and
height, and also in length between about 60 centimetres and about 1.5
metres, the pivot arm assembly 122 extends to the outer end of boom 124
and retracts with the box as in the second mode above. However, when the
front end wall of the box hits limit switch 111, and just prior to the box
side
1o flaps being folded down by side bars 114, pivot arm 118 comes down to close
the back flap of the box.
In a fifth mode of operation, where most of the boxes are under 24
inches in length, and only occasionally are longer, the position of pivot arm
118 on boom 124 could be set based on the length of the boxes being less
than 24 inches. If the box is over 24 inches in length, the pivot arm assembly
122 would extend pivot arm 118 to the outer end of boom 124 and retract, as
in the second mode above.
It will be appreciated that as soon as a box is picked up by the next set
of lateral conveyors 107, 109 or 140, 141, the respective previous set of
lateral conveyors 58, 60 or 107, 109 can be returned to their home positions,
or positioned to fit the width of the next box entering them, as measured in
measuring stage 25. In other words, as soon as a box clears any of the sets
of lateral conveyors, the next box can enter the cleared set of lateral
conveyors in front of it. In this way, one box can be measured in measuring
stage 25, while another box is having its flaps closed in flap folding stage
125,
and yet another box can be having its flaps taped or glued shut in sealing
stage 225. This results in a very fast operation for case sealer 10. The
operation is a little slower when one floating head is used for both the flap
folding stage 125 and the sealing stage 225.
3o Having described preferred embodiments of the invention, it will be
appreciated that various modifications may be made to the structures
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described above. For example, instead of using pneumatic cylinders to
control the various components of the case sealers, it will be appreciated
that
hydraulic devices or electric motors or solenoids could be used as well.
Programmable logic controllers are preferred for controlling the various
components of the case sealers, but other types of controls could be used as
well, such as simple timers. Limit switches have been described as the
preferred position sensors, but other devices such as photoelectric, infrared
or
other motion sensors or proximity sensors could be used as well.
Alternatively, the logic controller could provide the necessary inputs that
are
provided by limit switches 104, 111, 137 and 162. Instead of using toothed
strips 117, 119 to measure the width and height of the boxes, chains and
sprockets, with the pulses being picked up from the sprockets, can be used
with sensors 100 and 102 to measure height and width, if desired. In other
words, instead of using a cylinder 99 coupled directly to pick-up head 103, a
continuous chain running around sprockets could be used with head 103
mounted to pick-up pulses from one of the sprockets, and photo eye 115
mounted on the chain.
If desired, when a box arrives at sensor 137 of the flap folding stage
125, the logic controller could activate cylinders 85 and/or 87 (see Fig. 3)
to
move the conveyors 107, 109 and/or 140, 141 inward to a desired width, as
this is the same width measured in the measuring stage 25. For example, if
the box width measured by the measuring stage 25 is 10 inches (or counted
40 teeth) the controller could calculate and then activate the cylinders 85
and
87 to move lateral conveyors 107, 109 and 140, 141 to suit the 10 inch width
box. In order to do this, however, the logic controller must know the position
of the lateral conveyors 107, 109 and 140, 141. This can be accomplished by
using proximity sensors 165 and 166 (see Fig. 6) and toothed strips 167, 168,
in much the same manner as in the case of proximity sensor 100 and toothed
strip 117. Sprocket teeth pickups could also be used with proximity sensors
100, 165 and 166, as mentioned above.
As will be apparent to those skilled in the art in light of the foregoing
disclosure, many alterations and modifications are possible in the practice of
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this invention without departing from the spirit or scope thereof.
Accordingly,
the scope of the invention is to be construed in accordance with the substance
defined by the following claims.
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