Note: Descriptions are shown in the official language in which they were submitted.
'79~
T~lis invention relates to labelling equipment for applying
labels to portions of containers such as bottles and more particularly
to equipmellt for applying lahels that wrap around the outer surface
of the container and may be heat shrunk to the contours of the
container.
It is well known to utilize mechanical handling equipment
to apply labels to a container or the like. Such equipment usually
includes a drum upon which the label is secured and which moves the
label into engagement with the outer surface of the container. The
label adheres to the container and is subsequently wrapped around the
container by rolling it along a fixed surface.
In order to improve the efficiency of such machines it has
been proposed to derive the rolling motion of the container from the
rotation of the drum. The container is located between a stationary
surface and the drum so that continued rotation of the drum will roll
the container along the stationary surface. Whilst this arrangement
simplifies the machine it has been found unsatisfactory in the
handling of large labels.
In order to increase the capacity of the machine it has been
proposed to mount the containers on a large wheel which rotates in
synchronism with the label carrying drum. As each container passes
the drum it is rotated on its own axis partially to wrap the label
onto the container. Whilst this arrangement offers certain benefits
in terms of machine capacity compared with prior art machines, it
requires each container to be mounted on the wheel so as to be
rotatable about its own axis. This necessarily complicates the
machine and increases its cost. Further it does not overcome the
problems of applying large labels to containers.
It has previously been proposed to provide a
labellinq machine includinq a label carrier havinq a
plurality of support portions each operahle to receive and
retain a label and move the label alonq a predetermined path
at a predetermined speed, a container feeder operable to
- 2 -
9~
direct containers to a position adjacent the predetermined
path, and a drive system including transfer means to bring
a portion of the label into contact with the container and
drive means to rotate the container at a peripheral speed
greater than the predetermined speed whereby upon contact
of the label with the container, the label is drawn under
tension from the support portion and onto the container.
It has been found that by inducing rotation of the
container at a speed greater t~an the peripheral speed of
the drum, the label is drawn off the drum under tension.
This prevents bucking of t~e label and enables large labels
to be applied to containers. It is preferred to induce
rotation of the container by means of a belt entrained
around the drum, but moving at a greater speed than the drum.
~5 The belt leaves the drum at a location to engage a container
and carries the label with it. Thus the container, belt and
label are moving at a speed greater than the periphery of
the drum to pull the label under tension from the drum.
This drive arrangement avoids the need for separate rotatable
pads for each container and thereby results in reduced cost,
simplification a~d increased versitility for the machine.
The general improvement in labelling machines has
resulted in increased use of rolls of labels which are
individually severed as they are placed on the drum. The use
of such rolls has avoided the problems associated with feeding
individual precut labels from a batch, but some difficulty
has been encountered in severing labels from the roll.
Flying knife shears have been utilized, but these require
accurate adjustment to prevent rapid wear of the cutting
edge whilst ensuring the label is completely cut.
In our Canadian patent 951,685 there is disclosed
a knife arrangement in which a stationary knife is inclined
to the axis of rotation of a rotating knife to achieve a
progressive cut across the width of the label. This arrange-
ment has been successful in achieving complete cutting of
the label without premature wear of the cutting edge. With this
arrangement the label is engaged by a drum prior to severing and
a tension induced in the label by rotating the drum at a greater
peripheral speed than the feed rate of the label roll. It has
now been found that the induced tension may cause the label to
be torn from the roll as the knife approaches the end of its
cutting action. This is due to the progressive reduction in
width of unsevered paper which must resist the tension applied
to the label. The tearing of the label is undesirable because
of its appearance and hecause of the misregistration of the
label on the drum.
In the prior proposal there was provided for use in a
labelling machine having a feed mechanism to feed a strip of
labels along a predetermined label path and into engagement with
a label carrier, a cutter assembly located in the path for
severing labels from the strip, a cutter assembly comprising a
fixed support, a first cutting element attached to the fixed
support to extend transverse to the strip, a rotatable knife
carrier mounted for rotation about a first axis, a second knife
element attached to the rotatable knife carrier Eor movement
therewith, a drive means to rotate the rotatable knife carrier
about the first axis and move the second knife element past the
first knife element to produce a cutting action, the knife
elements diverging in the direction of travel of the second
knife element to provide progressive severing of the strip in a
direction transverse to the strip, and cam means associated with
the rotatable knife carrier and moveable into the path to engage
the strip and during a latter part of the cutting action out of
3~
the path to disengage the strip whereby tension is removed from
strip between the cutter assembly and the label carrier during
the latter part of the cutting action.
In the preferred embodiment of this prior application a
cam portion is mounted on a rotating knife holder to engage the
label being severed from the roll. The cam portion is
positioned ahead of the knife blade and moves out of engagement
with the label as the knife blade approaches the end of its
cut. The label is then slack as the cut is completed to avoid
tearing of the label.
Increasing use is being made of wrappers which cover a
major area of a container. These wrappers are made from heat
shrinkable material so that they may be printed in planar form
and subsequently shrunk to the shape of the container by the
application of heat. One machine available for applying these
wrappers forms a sleeve around a mandrel and then slides the
sleeve over the container prior to the application of heat.
Such a machine requires the sleeve and container to be moved in
a number of directions to bring them into register and
consequently has a comparatively low through-put. A further
disadvantage is that the sleeve must be of greater diameter than
the container for assembly and therefore heat must be applied to
the whole container to shrink the sleeve to the container.
It has now been realized that the label application and
cutter assembly previously proposed possesses particular utility
in the handling of wrappers since control of the wrapper is
maintained at all times.
It is therefore one object of the present invention to
provide labelling equipment which obviates or mitigates the
above disadvantage.
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11'~'7'~
According to one aspect of the present invention, there
is provided a labelling machine for applying heat shrinkable labels
to a container, said machine comprising a label feeder, a label
applicator to receive labels from said feeder and apply a leading
edge of said label to said container, drive means to move said
container past said applicator and draw the label onto the container
to form a cylindrical sleeve, a heat ch~er and a conveyor to move
least a portion of the container through the heat chamber and cause
said label to shrink and conform to the container.
As the label is tightly wrapped to the body of the container,
only a portion of the container requires heating.
An embodiment of the invention will now be described by way
of example only with reference to the accompanying d~awings in which:-
Figure 1 is a perspective view of a preferred embodiment
of labelling equipment looking generally from an end of the equip-
ment from which bottles are~fed to receive labels or wrappers;
Figure la is an elevation of the equipment shown in
figure 1.
Figure 2 is a plan view having portions sectioned to show
details of the labelling equipment;
Figure 3 is a sectional view on line 3-3 of figure 2 show-
ing a portion of the equipment;
Figure 4 is a further plan ~iew showing a part of a label
feeder assembly to a larger scale than that used in figure 2;
Figure 5 is a view on line 5-5 of Figure 4 to illustrate
the operation of cutting blades used to sever individual labels
from a strip of labels;
-- 6 --
1117t7~7~
Figure 6 is a side view of the label feeder assembly
showing some parts in section;
Figure 7 is a compound view of a label carrier which
receives labels from the label feeder assembly, the right half being
in section and the left half being generally an elevation and
Figure 8 is a section on the line 8-8 of figure 4.
Figure 9 i5 a view on the line 9-9 of figure 1.
The drawings illustrate labelling equipment capable of
handling a strip of labels supplied on a spool, severing these labels
individually, handling the labels and then applying them to bottles
which are controlled and fed through the labelling equipment.
Although the equipment is capable of use with various sizes of
bottles, it is particularly designed for large bottles or other con-
tainers having cylindrical portions for receiving wrap-around labels,
and a tapered portion adjacent the base.
These labels tend to be unwieldy and therefore difficult to handle.
Also, because of the length of the labels they tend to buckle or
apply unevenly with unacceptable results. The present equipment
controls the labels and applies them to the bottles while maintaining
some tension in the labels7 As a result the labels are applied evenly
and positively to the bottles or containers. This control facili-
tates the application of labels that wrap the bottle completely
to provide coverage of the major portion of the bottle and also
permit handling of heat shrinkable film material.
Reference is now made to Figure 1 which illustrates a
preferred embodiment of labelling equipment 20 for use in applying
wrap-around labels to large plastic bottles which are tapered at
11'~'7'~9~
their lower end. Labels in the fo~m of a strlp or web 22 are
fed f~om a spool 24 to meet individually with bottles 26, 28 which
are initially fed to the equipment by a conveyor 30. The bottles
meet a separator 32 which allows them to be moved individually by
a bottle feeder 34 to a point where each bottle recei~es a label
from a label carrier 36. At this point, each of the bottles is
supported on a rotatable platten 37 to allow the label to extend
below the bottle in a skirt. The platten 37 is part of a conveyor
41 described in detail below. The bottle is then controlled by a
bottle drive system 38 which rolls the bottle to receive the label
and then transfers the bottle to a conveyor 43 over a heat chamber
39 to shrink the label onto the tapered portion of the bottle.
The strip 22 of labels is drawn by a label feeder assembly
40 which also includes a cutting head as will be described later.
As the labels leave the feeder assembly 40 they are attached
individually to the label carrier using a pneumatic vacuum system
in the carrier 36. The labels then pass a glue applicator assembly
42 before being applied to bottles.
The general arrangement can also be seen in Fig. 2. In
this view an end of the strip 22 has been captured by label carrier
36, and preceding labels 44, 46 are attached to the carrier under
the influence of the vacuum system as will be described. A label
48 precedes label 46 and has almost completely separated from the
carrier 36 in the course of application onto a bottle 50. Details
of Fig. 2 will be described more fully in combination with subsequent
views but
~ 9 ~
at this point it is important to note that the peripheral
speed of the portion of the label carrier 36 which receives
the labels is slightly greater than the linear speed of the
strip 22 to maintain some tension in the iabel as it trans-
fers from the label feeder assembly 40 to the label carrier
36. Similarly, the bottle drive system 38 is arranged to
move the periphery of the bottle slightly faster than the
label is moving with the carrier 36. This again ensures
tension in the label as it is transferred from the carrier
36 to the bottle 26
For the sake of convenience the label feeder
assembly 40 will be described in detail before then describ-
ing the label carrier 36 and bottle drive system 38. Other
parts of the equipment will be described where they relate
to the feeder assembly, label carrier, and drive system.
Reference is next made to Figs. 2, 4 and 6 with
particular reference initially to Fig. 4 to describe the
main componen~s of the label feeder assembly 40. The strip
22 of labels is drawn into the label feeder assembly by a
main or drive roll 52 combining with a rubber pinch roll 54
which is biased towards the main roll 52 by a pneulnatic
actuator 56 operating on the end of an L-shaped arm 58 which
is in fixed relation with a pair of arms 60 and which pivots
about an upright spindle 62. The arms 60 support a further
spindle 64 about which the roll 54 is free to rotate. Con-
sequently upon energizing the actuator 56 the pinch roll 54
is biased into engagement with the main roll 52 resulting in
a driving force to progress the strip 22 through the assembly.
The strip is also guided by idlers 66, 68 which both tend to
remove any natural curl from the labels and also ensures
that the strip is in good contact with the main roll 52 before
the strip meets the pïnch roll 54. The strip passes from the
main roll 52 through a cutter assembly 70 and into engagement
with the periphery of the carrier 36 where it is held by
vacuum pads as will be described below. Because of the
yrellter periphcral spe~d of the carrier 36, the strip slips
relative to the carrier so that it is under tension. AS
seen in Fig. 4, the strip is moved from the main roll 52
into a position for severing into individual labels by a
cutter assembly 70. This assembly consists of a stationary
portion 72 and a rotating cutter head 74. The stationary
portion 72 includes a blade 76 attached by screws 78 to a
fixed bracket 80. The blade 76 can be aligned with a
further blade 82 in a notched roll 84 using adjusting screws
lQ 86 before tightening screws 78 completely. The blade 82 is
held in the notched roll 84 by screws 86.
The arrangement of the blades 76 and 82 is such
that the strip is cut progressively across the width of the
strip as indicated in Fig. 5. ~ere it will be seen that
the blade 76 is inclined to a vertical axis whereas the
blade 82 is vertical. As shown, the strip is being cut at
a point 88 and has already been cut up to that point running
from the bottom to the top of the strip 22.
It has been found that the arranyement of blade
76 relative to blade 82 results in an improved cut because
of the scissor action as the blades come together while the
strip is moving past the blades.
The inclination of the blade to the ~ertical axis
ensures a square edge is cut as the label passes through the
cutter assembly 70 so that it is not necessary to interrupt
movement of the label whilst it is being cut.
It will also be n~ted that the trailing edge of ~he
blade 82 cooperates with blade 76 to perform the cutting action.
In practice it has been found that a slight interference between
the cutting edges is possible without detremental wear of the
cutting edges. The interference is achieved by locating the
blade 76 within the path of the blade 82 by adjustment of
an adjusting screw 91.
A cam lobe 85 is attached to the notched roll 84
in advance of the blade 82. The cam lobe 85 is posit;oned
so that its peripheral surface 87 engages the strip 22 as
it moves past the stationary blade 76. As may best be seen
in Fig. 4, the strip 22 is deflected in its path so that the
effective distance between the stationary blade 76 and the
point of engagement of the strip with the carrier 36 is
increased. Since the strip is firmly held by pinch wheel 54
and main roll 52, the strip will slide relative to the peri-
phery of the carrier 36. ~17 ~ ~9~
-- 10 --
'7~7~
~s the notched roll 84 continues to rotate, as indicated
in chain dot lines in Fig. 4, the cam lobe 85 moves out of the
path of the strip 22 so that there is a temporary slack in the
strip 22. The cam lobe 85 is positioned so as to disengage the
strip 22 as the blades 76, 82 complete the cut. Since the tension
is momentarily released from the strip, the tendency to tear the
label from the strip is reduced.
It will be apparent that the path of the strip may be
modified so that the cam engages the strip over a reduced arc pro-
vided that sufficient slack is created in the label to permit the
cut to be completed before the difference in speed between the
carrier 36 and the main roll 52 again introduces tension in the
label.
When using unsupported film of heat shrinkable material,
such as that sold under the trade name Cellu-lambl(Trade Mark)by
Cellucraft Inc. there may be a tendency for the film to stick
to the rotating cutter 82. As can be seen in figures 4 and 8, the
roll 84 includes an axial passage 300 which is intersected by a
number of radial passages 302 extending to the periphery of the
notched roll 84. A wear disc 304 is attached to the under surface
of the notched roll 84 and includes an arcuate aperture 306 in
register with the passage 300. A manifold plate 308 is attached
to an upper surface of a stand 310 that supports a drive shaft 95 of
the notched roll 84 and is biased into engagement with the wear
disc 304 by spring :312.
A supply line 314 is connected to a port 316 in the main-
fold plate 308 to supply air to an outlet 318 in the upper surface
320 of the mainfold plate 308. The outlet 318 is located at the
same radial spacing as the aperture 306 so that during a portion
of each rotation of the cutter assembly, air is supplied to the
axial passage 300 and radial passages 302.
The radial passages 302 are located behind the knife 82
and the outlet port 318 adjusted so that air is admitted to the
passage just as the strip 22 is cut. The radial passages 302
direct the air against the uncut portion of the strip 22 to push
it away from the blade 82 and onto the drum 36.
-- 11 --
T'ne passages 302 are not trul~ xadial but do in f~ct direct
air from the roll 84 ~t an ~ngle in ~dy~nce of the xadial line.
This forw~rd incli.nation assists in ~eeding film past the knife~
The period of the air blast may be adjusted b~ varying the
¦ 5 length of the aperture 306 and the timing of the air blast may be
¦ adjusted by rotation of the manifold plate 308.
¦ Turning now to Figure 6, it will be seen that the parts
described with reference to Figure 4 are driven ~rom a single input
spur gear 90 (part of which is shown). The
gear meshes with a second gear 92 which is in turn in mesh
with a further gear 94. The gear 92 is attached to the
lower end of a shaft 95 to drive the notched roll 84. Simi-
larly, the gear 94 is attached to the planetary portion of
an epicyclic gear box 96 to drive the sun gear which is
attached to the lower end of a shaft 98 associated with the
main roll 52 (Fig. 4). (~or simplicity, the planetary gears
and sun gear have been omitted from the drawing.) The
epicyclic gear box 96 includes a housing 100 which for the
moment can be considered to be stationary. As a result,
drive from the intermediate gear 92 results in rotation of
the shaft 98 which is attached to the main roll 52 (Fig. 4)
to drive the strip 22.
The epicyclic gear box 96 permits differential
movement between the shafts 95 and 98. If the housing 100
is stationary, then the shaft 98 will rotate at a speed
dictated by the relationsh~p bet~een the planet and sun
gears in the epicyclic gear box; However it is possible
- 12 -
'7'7~;~
..1
to eithcr aclvance or retard the shaft 98 relative to the
sh~ft 95 by turning the housing 100 about the axis of shaft
98. This is necessary because of the allowance in length
i of each label. If it is found that the labels are being
J 5 cut either in advance or behind the desired cutting line,
then adjustment can be made througn a motor and gear box
102 which drives a pinion 104 in mesh with a ring gear 106
i associated with housing 100. The motor and gear box is
reversible and is driven via a control circuit 108 which
10 receives a signal from a device which senses the location
of a label to determine whether or not the cutter should
be advanced or retarded in relation to the labels. The
device senses a predetermined marking on the labels and
produces a signal to move the motor and gear box in an
15 appropriate direction to ensure the cutter engages the label
at the required position. The structure shown in Fig. 6
has a particular advantage from the standpoint of adjustment
and maintenance. It will be seen that the structure includes
a plate 110 resting on a part 112 of the frame of the equip-
20 ment. The structure is located relative to the part 112 by
a bearing housing 114 attached to the part 112 and containing
a cylindrical portion 116 of the structure. The plate 110
can slide on the part 112 and rotate about the axis of shaft
95 so that the assembly shown in Fig. 6 can be swung about
25 this axis and into a position for more convenient adjustment
and maintenance. This is also made possible by the fact
that such movement takes place about the axis of the shaft 95
so that the engagement of the gears 92, 94 is not affected.
The assembly shown in Fig. 6 can be locked in posi-
30 tion using a simple engagement fitting controlled by a handle
118 and with the structure locked in position by this handle
it assumes the position shown in Figs. 1 and 2. Such movement
is particularly useful for adjusting the blade 76 (Fig. 4)
of the stationary portion 72 of the cutter assembly 70. It
35 will be appreciated that the spur gear 90 shown in Fig. 6
is driven through a suitable drive chain from a bull gear
121 shown at the bottom of Fig. 7. It will become apparent
- 13 -
~i'7'~'79~
that ~his ensures that the label carrier 36 shown in Fig. 1
is driven synchronously with the notched roll 84. The reason
for this will become evident from subsequent description.
Returning to Fig. 2, the label carrier 36 consists
essentially of ~ large wheel having a discontinuous periphery.
Four raised peripheral pads 120, 122, 124 and 126 are pro- `
vided spaced equally about the periphery of the wheel. As
will be described with reference to Fig. 7, these pads are
provided with openings connected to a vacuum system to hold
labels such as labels 44 and 46 on the pads.
Fig. 2 shows a label 129 which is projecting outside
the label feeder assem~ly 40, but has yet to be severed from
the strip 22. It will be seen that the leading edge of the
label projects beyond the leading end of the pad 126 whereas
the label 44 which has been severed from the strip sits on
the pad and does not overhang the pad. This is because the
wheel is made to move with sufficient peripheral speed that
it creates slippage between the pad 126 and the label 129.
Because the vacuum system maintains the label in contact
with the pad, a tension e~ists in the label and this ensures
that the label is drawn into firm engagement with the pad.
When the label is severed from the strip, it will have
slipped on the wheel to a point where the leading end of
the label lies immediately adjacent the leading end of the
pad 126. As soon as the label is severed it will be drawn
onto the pad and take up a position such as that shown for
label 44. This process continues as the severed label pro-
gresses with the wheel past the glue applicator assembly
42. Here glue is applied in a conventional manner, the
applicator assembly being controlled to move out of engage-
ment with the wheel should there be no label on the pad.This control will be described subsequently.
- 14 -
7'~9~
After a label such as l~bel ~6 has passed the applicator
asse~bly 42 a leading end is stripped off the wheel by ~ pai~ of
belts 128 (one of which is seen in Figure 2 and both of which can
I be seen in Figure 7?~ These belts pass around the wheel 119 driven
¦ 5 by a roll 130 whlch causes a linear velocity in the belts greater
¦ than the peripheral velocity of the wheel 119. Bottle feeder 34
is driven also from the bull gear 121 (Figure 7) to cause bottles
to be in position to receive labels from the wheel 119. The bull
¦ gear 121 also drives the conveyors 41 and 43 so that the plattens
~ 10 37, 342 are in synchronism with the bottles transferred by the
¦ bottle feeder 34. The conveyor 41 can best be seen in figure la and
¦ includes a pair of endless linked chanins 326 interconnected by
lateral webs 328. The plattens 37 are rotatably mounted on spindles
330 and are of sufficient height to allow a skirt formed by the label
to depend from the bottle. The diameter of the plattens 37 is
chosen to correspond to the largest diameter of the bottle to which
¦ the label is applied. The periphery of the platten therefore provides
a support for the lower edge of the label enabling the seam in the
label to be pressed down as it is rolled. In the event that the skirt
does not extend fully to the base of the bottle, the platten 37 may
be formed with an upstanding`edge so as to provide the desired support
for the label. The chains 326 are entrained around a drive gear
332 driven by the bull gear 121 an idler 334. As the bottles are fed
by the separator 32 into the bottle feeder 34; the platten 37
engages the underside of the bottle and moves in synchronism toward
the drum 36 and into position to receive the label. The bottle 50
for instance has reached a reaction pad 132 supported by a wall 134
and is biased into contact with the belt 128 so that the bottle is
driven linearly along the conveyor 30 at half the speed of the belt.
The belt guides the leading edge of the label into contact with the
outer surface of the bottle 50 which is moving faster than the label,
so that as soon as the adhesive on the label comes into contact with
the bottle, the label begins to adhere to the bottle and is pulled
off the wheel while maintaining sliding engagement with the assoc-
'7'~9~
iated one of the raised pads on the wheel. This tension ensures aneven ~nd controlled application of the label ~s the bottle rolls in
contact with the pad 132. An ~uxilia~ ~aCuum pad 136 is provided
to further support the label after it has slid off the pad 132 and
before it ls applied completely to the bottle 50. This will be
better understood with reference to Figure 3 which shows a sectional
view through the auxiliary vacuum pad 136. Once the label has be~n
applied, the conveyor 41 passes over the idler 334 to remove the
platten 37 from the bottle. The bottle is transferred onto conveyor
43 across a bridge 340 by a further single belt 138, which is also
driven by the roll 13. The bottle is engaged by a platten 342
mounted on the conveyor 43 and of significantly smaller diameter
than the base of, the bottle. The conveyor 43 is supportedalong its
length by a rail 341 to provide a stable support for the bottle 28. The surfaoeof reaction pad 132 is provided with inclined ribs which cooperate
with the bottle surface to force it down onto the conveyor 43. As
the bottleis advancedby the conveyor 43, it passes over the heat
chamber 39 where the heat causes the label to shrink and conform to
the shape of the bottle with the skirt shrinking onto the lower
surface of the bottle. Typically, the temperature required to shrink
the material is as low as possible and dependant upon a variety
film materials, but in the range of 100 - 250F. The cooperation
of the belt 138 and reaction pad 132 causes rotation of the bottle
to ensure the skirt is uniformily heated. Thereafter the bottle
passes onto a conventional conveyor.
Details of the heat chamber 39 can best be seen in figure 9.
The chamber 39 comprises a duct 343 along which the conveyor 43
passes. The duct includes a base 344 and a pair of side walls 346
each having an inclined lip 348~ ~ manifold 350 is mounted on each
of the lips 348 and delivers hot air from a heat source and blower
(not shown) to the interior of the duct through a series of nozzles
352. The nozzles 352 are spaced along the length of the duct 343
and directed to the base 344. The nozzles 352 are formed from slits
in the manifold inclined at 45 to the longitudinal axis of the
manifold. This provides an air knife that sweeps across the skirt
from top to bottom as the bottle passes along the heat chamber 39p
- 16 -
:1~'7'~
Air from the interior of the duct i~ removed from each
end and reci~culated through the heater and blowers, The air
discharged from the nozzles 352 impin~es on'.the skirt depending
from the bottle 50 and causes the label material to shrink to
conform to the shape of the bottle.
It will be observed that only the lower portion of the
bottle is subjected to heat minimising the hot air required and the
risk of damage to the bottle. It will also be appreciated that
the label can be shaped to the neck of the bottle in a similar manner
by arranging a heat chamber at the appropriate level along the length
of the conveyor 43.
Returning now to the details of construction of the label
carrier 36, it is evident from Fig. 2 that the wheel 119 includes
two groups of vacuum pipes, an outer group 140 and an inner group
142. It will be seen that the outer pipes 140 serve the ends of the
labels whereas the inner pipes 142 serve the centres of the labels.
With this arrangement it is possible to release or more positively
secure the centre of the label independently of the ends and vice
versa.
Reference is next made to Fig. 7 to describe the
structure of the label carrier 36. The carrier rotates
- 16a -
about all axi~ dcfined by a vertical shaft 1~ driven from
a main drive and gear ~ox 146. The bull gear 121 is attached
to the shaft 144 and drives all of the other parts of the
equipment through a conventional drive chain.
The shaft 144 passes through a bearing housing 148
and is supported at ends of the housing by suitable bearings
150, 152 which include a thrust bearing. The bearing housing
148 includcs a flange 154 sitting on a part 156 of the frame
of the equipment and attached by suitable bolts 158.
The bearing housing 148 also supports a vacuum
distributor 160 having a lower part 162 fixed to the bearing
housing by a further flange 164 and an upper or movable
portion 166 which rotates with the wheel 119 driven by a
pin 168 as will be described. The portions 162 and 166 are
machined to define smooth faces in engage~ent with one ~
another to facilitate the upper portion riding on the lower
portion as the upper portion rotates.
The lower portion 162 defines an annular recess
170 covered by a plate 172 and seal 174. These parts com-
bine to define an annular manifold served by a vacuum con-
nection 176. This manifold then serves the pipes 140, 142
by way of concentric rows of openings 178, 180 in the
fixed part 162 and corresponding openings lfl2, 184 associ-
ated with the pipes 140, 142. The openings 178, 180 extend
partially about the part 162 as illustrated in broken out-
line in Fig. 2. Consequently, as the wheel 119 rotates
the openings 182, 184 are affected by vacuum when they coin-
cide with openings 178, 180. It w;ll be evident that the
size of openings 178, 180 can be varied to provide different
degrees of vacuum in the pipes 140, 142 as the wheel 119
rotates.
Each of the pipes 140, 142 terminates at its upper
extremity in a fitting which connects the pipe to one of
a series of upright bores lB6. Each of these ~ores acts
as a manifold to a series of radial openings 188 for
drawing air from the front of one of the raised pads such
9~
as ~ 120. ~ bel is shown in ghost outline fixed to
such a pad. In f~ct, these p~ds are preferably of an
elastomeric m~terial bonded to an outer ring 190 which is
made up of two halves and attached to the main body of the
wheel.
~ ach of the bores la6 is associated with the pipes
140 at the leading end of a label has a vacuum sensor 192
at its lower end. This sensor normally rides on a *rack
194 until it passes a point at which a label should be picked
up. In the event that a label is picked up there will be a
build up of negative pressure in the bore 186 which will
retain a loose plunger 196 against a seat 198 to thereby
seal the bore 186. The plunger 196 will then be in a raised
position and as the wheel 119 rotates the plunger will pass
above an electrical switch 200. However, in the event that
a label is not supplied to the wheel for som~e reason there
will be insufficient vacuum built up in the bore 186 to
maintain the plunger in its upper position and it will then
drop off the end of the track into the position shown in
Fig. 7. As the wheel ro~ates the plunger will contact the
switch 200 and this switch will be used to energize an
actuator 202 (Fig. 2~ associated with the glue applicator
assembly 42. Energizing this actuator results in moving
the applicator assembly away from the wheel to avoid applying
glue to the wheel in the absence of a label.
After the plunger 196 has met the switch 200, it
will continue in the dropped or lower position until it
reaches an incline 204 at a leading end of the track 194
which raises the plunger back to a position in which it
engages seat 198.
The wheel 119 includes a central boss 206 which
locates on an upper extremity of the shaft 144 and is engaged
on the shaft by a key 208. An extension 209 on the upper
extremity of the shaft is threaded to receive a knob 212
which retains the wheel on the shaft. ft will be evident
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'7';'"79~
that once the knob is removed it is possible to disconnect
the pipes 140, 142 and to lift the wheel off the equipment.
Once this is done the distributor can be. removed so that
it is quite simple to service the equipment and to change
parts if this is necessary for different labels.
Returning to the operation of the equipment, in
I the position shown in Fig. 2, pipe 140 adjacent label 128
is applying vacuum and has picked up the forward end of the
label. As the wheel 119 rotates this label remains in con-
tact although it will slide on the wheel until the label
is separated from the strip 22. At this point it will have
dropped back from label 44 by the amount of the space between
pads 126 and 120 and will then effectively take up a position
similar to that shown for label 44. Because a label has
been attached to the wheel, the sensor 192 (Fig. 7) will fail
to touch the switch 200 so that glue will be applied to the
label as it continues to move into position for application
to a bottle. It should be noted that it is possible with the
arrangement of pipes 140, 142 to apply more vacuum at the
centre of the label during gluing if required and in fact
to vary the vacuum effect on the label by changing the sizes
of the holes in the parts of the distributor serving the
pipes. As mentioned earlier, the leading end of the label
is stripped from the wheel by the belts 128 and at this
point vacuum is no longer applied to the leading end of the
labei. Also, at this point the label becomes attached to a
bot~le and in order to simplify slippage of the label on the
wheel it is preferable to discontinue vacuum through the pipe
142 to the centre of the label and to rely on vacuum on the
trailing edge of the label through ~ne of the pipes 140.
Thus the holes 180 terminate ata position corresponding to
the circumferential position of the conduit 140 just after
the leading edge of the label is detached from the suction
pad. The initial contact between the label and the bottle
takes place just where the belt leaves the wheel and the
differential speed between the belt and the wheel ensures
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11'7'~ 3i~
t~nsion in the lab~l. This clifferential speed is achieved
using a particul~r arrangcment of belt engagement on the
wheel 119 as will be described.
Reference is again made to Fig. 7 to describe the
S parts of the wheel 119 associated with containing the belts
; 128. These ~elts sit in respective recesses 210~ 212 in
radial engagement with slip rings 214, 216 made up in segments
and of a low friction plastic material such as polytetra-
fluoroethylene. In turn, these slip rings are in radial
engagement with brass wear strips 218, 220 which are also
positioned in the ring 190 at the bottom of the respective
recesse~ 210, 212. As ~ result of this arrangement the belt~
128 can be driven at a llnear speed grca~cr ~han the peri-
phcral spe~d of the wheel without interfering with the labels
lS before they are ready to be stripped from the wheel. However,
as soon as a label is stripped off the wheel and in engagement
with a bottle, the speed of the label becomes that of the belt
thereby ensuring tension in the label as it is stripped off
the wheel.
The belts 128 are driven continuously by roll 130
which in turn is driven from the bull gear 121 (Fig. 7)
through suitable drive members. Tension is maintained in the
belt by an idler 222 and, as mentioned earlier, the single
belt 138 is also driven by the roll 130. This belt passes
around an idler i!24 and tensioning idler 226 so that the
belts 128 and 138 combine to roll the bottles along the
reaction pad 132 and subsequent pad 228 with a linear velocity
substantially equal to that of the conveyor 30. Guides 230
are shown in ghost outline to support the bottles at the neck
and to limit the possibility of thé bottles being toppled by
engagement with the label etc.
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