Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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CONTAINER INSPECTION AND SORTING SYSTEM
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
This invention relates to the inspection of containers and, in particular,
containers such as bottles,
which are transparent or translucent and allows the passage of light
therethrough. More
particularly, the present invention provides for the non-contact examination
of an individual
bottle in a line or stream of similar bottles travelling along a moving
conveyor, the bottles being
filled with an aqueous liquid such as a potable water-based beverage such as
beer or a soft drink.
The required inspection is effected and any cansequential action such as
sorting or rejecting the
bottles taken without the movement of the bottles being affected.
DESCRIPTION OF PRIOR ART
Various inspection systems have been proposed for examining a stream of
containers such as
glass bottles moving along a conveyor and these systems may be used to sort
the containers
based upon one or more of the bottle characteristics disclosed by the
examination. Many
previous systems of this type employ apparatus that are regularly disruptive
of smooth flow.
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Examples of such disruptions may be, for example, devices that remove
containers from a
straight conveying path for inspection; kickers; separators and diversion
elements that are prone
to knock containers down; and inspection stations that require some or all of
the containers to be
slowed, spun or even stopped in place.
Reference may be made to various arrangements by which bottle rim or side wall
inspection are
carried out for example, U.S. Patent 4,454,542 discloses a video rim
inspection technique; U.S.
Patent 4,391,373 discloses rim inspection using photocell pairs and US Patent
3,932,042 teaches
sidewall inspection techniques. U.5. Patent 4,121,103 teaches absorption in
the visible and
infrared regions and base analysis devices. U.S. Patent 5,903,006 teaches
using the absorption of
light in the infrared region to detect and evaluate the concentration of water
in an aqueous
solution. The light source used is a light-emitting laser diode emitting light
having a wavelength
within the range 1.3 to 1.9 Vim.
U.S. Patent 6,043,504 also teaches the use of a semiconductor light-emitting
device to "inter
alia" detect the presence of water and, in Col. 1 et seq. discusses the issues
with conventional
photoelectric switches and the available semi-conductor light-emitting
devices, particularly
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lasers which can provide light of the desired wavelength to the significant
exclusion of light of
other wavelengths. This means that the amount of the projected light, which is
absorbed upon
contact with water, is very high and a significant percentage of that
initially projected.
Consequently, it is possible to detect the large decrease from a beam which is
attributed to water
absorption of the light and hence to evaluate the presence or absence of
water. This patent also
teaches the general use of the photoelectric switch to detect the level of a
liquid composed
mostly of water. However, the method as taught leaves something to be desired
when applied to
the problem of determining whether a bottle containing a water-based beverage
is filled to the
correct level as the bottle is rapidly moving on a conveyor subsequent to it
being filled. The
problem arises not only because the meniscus of the beverage liquid is not a
planer surface but it
is exaggerated since the neck of a beer or soft drink bottle usually has a
small cross-sectional
area: Also because the filled bottle may be subjected to significant sway or
wobble because of
the high speed of the conveyors transporting the filled bottles to the next
stage in the process and
bottle contact with adjacent bottles and conveyor guide rails. This bottle
wobbling results in the
beverage liquid in the bottle becoming subject to agitation or oscillation.
More importantly,
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these systems scan the full width of the bottle or bottle neck and hence the
light beam encounters
all the material "creeping" up the bottle wall which, as discussed, can be
agitated and oscillate
making locating the actual fill height difficult and inexact. The result is
that it becomes most
difficult to locate the level of the beverage in the bottle. Consequently, in
the prior art devices
when the light beam scans the whole neck of the bottle it can encounter
several situations which
can result in an invalid evaluation of the liquid level resulting in, for
example, the rejection of a
bottle when the liquid level may actually meet the required level. To explain
more fully when
the liquid in a bottle is subject to oscillation such that, when the bottle is
at the evaluation station,
the liquid surface meniscus is momentarily at an angle such that the light
beam does not
encounter sufficient liquid to be absorbed to the degree necessary register as
meeting the
required standard level, it will register that bottle non-compliant with a set
standard. This results
in rejection when that should not have been the case.
U.S. Patent 3,784,827 describes a sealed radioisotope source for use in a
container inspection
system. This system involves passing y-radiation through a liquid containing-
container at a
position just below the desired light fill level. If the liquid is filled to
the correct height, the
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radiation is absorbed by the liquid. Alternatively, if the liquid is not at
the desired height, the
radiation passes through the container without absorption. The amount of
radiation passing
through the container indicates whether or not the container has been filled
to the desired height.
However, the x-radiation beam has a fan-like profile, which is less focussed,
and it is difficult to
provide reasonable assurance that no - or only an acceptably small number - of
low fills are
cleared. The system needs to be set in a conservative manner resulting in an
unacceptable
number of bottles being incorrectly designated as low fills and rejected.
In order to reduce the possibility of an incorrect evaluation of the liquid
level in the usually neck
region, of the container it is preferred that steps are taken to stabilize the
meniscus in each
container when it is in the inspection stations i.e. at the point of
evaluation. This can be
accomplished in a number of ways; for example; the bottle may be stopped for a
time sufficient
to allow the liquid to settle or the liquid contents of the bottle can be
rotated. This latter proposal
to some extent stabilizes movement of the meniscus, at least sufficiently to
hope that the critical
central area remains at a constant level. However, this is a complex and
costly operation.
Another method uses mechanical means such as a feed screw arranged to contact
and engage the
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container when in the inspection station and prevent it from as wobbling or
swaying. This
method however has obvious speed restrictions. This can be compared with prior
art devices
which provide continuous scanning across the full width of the container when
the detector can
be confronted with an aggregated signal from a wide beam of radiation, parts
of which may have
encountered liquid of various "thickness" and others no liquid at all. The net
result at best is that
the light received by the photo receiver must be subjected to processing
activities involving
initially an evaluation of the total radiation it receives and a comparison
thereof with a value
which has previously be determined to constitute a "low fill" or acceptable
level situation.
Once obtained, this information may be used to accomplish a number of
objectives, for example,
a container diversion device located downstream of the detection device of the
present invention
could be supplied with the information as to which containers are "low fills"
resulting in such
containers being diverted from the moving stream or line to be further
processed.
It is an object of the present invention to provide an inspection device for
more accurately
determining the fill height of aqueous contents in a bottle thereby reducing
the number of false
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rej ects.
It is another object of the invention to provide such a device which is
relatively inexpensive, easy
to maintain operating and which requires little space for installation.
BRIEF DESCRIPTION OF INVENTION
It has now been found that many disadvantages associated with prior art
contents level inspection
devices can be avoided and, more specifically, a more consistent exact
measurement of the
desired fill level can be obtained by effecting a single point evaluation of
the fill level. This
evaluation is made according to the invention essentially at the intersection
of the desired fill
height and the vertical axis of the bottle or more correctly, the bottle neck
portion. This location
which is arranged to be the central portion of the meniscus of the bottle
content liquid has been
found to be relatively insensitive to the oscillations and like movements of
the liquid content of
the travelling bottles caused by motions of the latter, such as wobbling. This
single evaluation is
effected by projecting a single pulse of light in the form of a narrow or fine
beam of light at the
neck of the bottle to be inspected, the beam being arranged to contact the
bottle substantially at
the intersection of the plane of the desired fill level and the central
vertical axis of the bottle or
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more specifically, the neck portion. The center portion of the meniscus is
arranged to be at or
immediately below the desired fill height. As a consequence, the pulse of
light either:
(i) contacts the body of liquid right up to the surface of that central region
of the meniscus
and is blocked or absorbed by the liquid, and
(ii) if above that central region of the meniscus, "sees" only glass (or
another light
transmitting bottle material) and is detected by the associated light
receptor.
With respect to (i) the receptor is not activated and does not generate a
signal. This signifies that
the filled bottle neck liquid level specifications are met and the bottle is
acceptable.
In the case of (ii), the beam is transmitted to the light receptor which then
generates a signal that
the bottle under test is a low-fill. i.e. unacceptable.
It may be noted that some bottling operation, such as the filler can impact a
small amount of
rotational movement to the bottle and its contents, this assisting
stabilization of the meniscus to
some extent.
In contrast to prior art devises, the use of a fine beam means that only a
relatively small amount
of liquid is needed to obtain a definite measurement which results in a simple
"yes" for
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acceptable or "no" for an unacceptable. To enhance this sensitivity, it is
very preferable that a
significant percentage of the light beam used be readily absorbed by the
liquid being detected. In
the present case, a beam tuned to the water molecule is preferred since the
beverage with which
the present invention is advantageously used has significant water content.
There are various
commercially available lasers which provide the desired characteristics and,
since these can be
relatively physically small, they can be installed in a plant without too much
difficulty.
Consequently, it is very preferred that the light source used according to the
present invention be
a laser tuned to the water molecule. It should be noted that these lasers
provide light having a
wavelength predominantly in the range of from about 1.40 to 1.55 microns. One
supplier of such
lasers and associated light guides etc. is IDEC Corporation of Japan.
This generated signal is arranged to activate a bottle rejection system such
as a hopper; slat
rejecter or the like. However, it is preferred that the novel rejecter device
as taught in Assignees'
Pending U.S. Application Serial No. 09/891,616, (F. Linton), the contents of
which application
are incorporated herein in their totality be used and this combination
constitutes another aspect of
the present invention.
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It is further preferred that the combination of detector and deflector
combination of the present
invention be used in combination with a container tracking device which delays
the signal from
the detector to the defector.
It will be appreciated that any located low-fill is not generally rejected at
the inspection station.
The action point of rejection, is usually downstream but it is then necessary
to track the progress
of any found low-fill so that the rejection device is activated to reject it,
and only it, when the
low-fill reaches the rejection station. Such tracking systems axe readily
commercially available
and routinely used the art, one such system is a shift register system, an
example of which is the
"Checkmate" software system of Krones Inc., 9600 South 5$t" Street, Franklin,
WI 53132-0100.
Further and detailed description thereof is felt unnecessary.
DESCRIPTION OF INVENTION
In one aspect, the present invention provides an inspection device for
determining if the level of
an aqueous liquid in a container having a neck portion is at a predetermined
level, at least a zone
in the neck portion containing at the predetermined level being adapted to
transmit light, said
device comprising a first means adopted to emit a single pulse of light in a
narrow beam toward a
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second and opposing means adapted to detect said light, the space between the
first and second
means defining a container inspection station, means to transport containers
to be inspected
through said station and means to initiate projection of said pulse of light
when a container to be
inspected is at a position in said station such that said pulse contacts said
bottle neck portion at a
location representing the intersection of the predetermined level and a
central vertical axis of said
neck.
In another aspect, the present invention provides a sorting device for
separating from a stream of
bottles containing an aqueous liquid travelling along a pathway, which bottles
have a neck
portion which is able to transmit light, those bottles whose liquid content
meets a predetermined
level, which level is located in said neck portion, from those containers
whose content does not
meet said predetermined level, said device comprising:
a first means adopted to emit a single pulse of light in a narrow beam toward
a second and
opposing means adapted to detect said light if the Ievel of liquid in said
container fails to meet
the predetermined level, the space between the first and second means defining
a container
inspection station, means to transport bottles to be inspected through said
station and means to
II
It is furt
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initiate projection of said pulse of light when a container to be inspected is
at a position in said
station such that said pulse contacts said container neck portion at a
location representing the
intersection of said predetermined level and a central vertical axis of said
neck, and container
deflector means which, in response to a signal initiated by said second means,
is adopted to
remove said stream of containers.
In another embodiment, the present embodiment provides a method for detecting
in a stream of
aqueous liquid filled containers travelling along a pathway, which containers
have a neck portion
which is able to transmit light, those containers whose liquid content meets a
predetermined
level, which level is located in said neck portion, from those containers
whose content does not
meet said predetermined level, said method comprising: passing said bottles to
a station where a
pulse of light in a narrow beam is projected at a portion of the neck of each
bottle which includes
the intersection of the said predetermined level and a central vertical axis
of the container and
where the container contents do not meet the predetermined level detect such
beam which passes
through the container neck of the bottle under inspection.
In yet another embodiment, the present invention provides a container sorting
method for
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separating from a stream of liquid filled containers travelling along a
pathway, which have a
neck portion which is able to transmit light, those bottles whose liquid
content meets a
predetermined level which is located in said neck portion from those whose
content does not
meet said predetermined level, said method comprising: passing said bottles to
a station where a
pulse of light in a narrow beam is projected at a portion of the neck of each
container which
includes the intersection of the said predetermined level and a central
vertical axis of the
container neck detecting any such beam which passes through the bottle neck
and using same to
activate a container deflector which removes the container in question from
the stream of
containers without affecting the motion of the other containers in the stream
of bottles.
It will be appreciated that the present invention may be used with advantage
to handle different
types containers which meet the light transmittance requirements but it is
especially useful in the
processing of containers especially bottles and specifically glass bottles
containing soft drinks
but especially alcoholic beverages such as beer.
The present invention will be further described, but not limited by, reference
to the drawings in
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which:
FIG. 1 is a diagrammatic cross-section through an inspection station showing
the adjustable
support which carnes the optical detector system according to the present
invention.
FIG. 2 is a perspective view from upstream of part of the inspection station
of FIG. 1 along the
conveyor and showing the inspection station with an associated bottle infeed
worm arrangement.
FIG. 3 shows in detail the adjusting mechanism for adjustion of the deflector
system according
to the present invention.
FIG. 4 is a detail of the connections of the trigger device and the emitter
head of the inspection
station; and
FIG. 5 is a cross-section of a bottle neck showing the substantially
consistent meniscus level
despite movement of a bottle at the inspection station.
FIG. 6 is a cross-sectional view of a deflector device used according to the
present invention.
FIG. 7A is angled perspective of the paddle unit shown in FIG. 6 and 7B is an
end elevation in
the direction of arrow A in FIG. 6A of the paddle unit.
FIG. 8 comprises diagrammatic cross sectional views showing a bottle on a
conveyor, in FIG.
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8A at the point the paddle plate is initially contacting the bottle, (the
angle of the paddle plate to
the vertical being exaggerated) and in FiG. 8B secondary contact occurring
slightly later in the
rej ection stroke.
FIG. 9 is an angled perspective view of the deflector installed on a bottle
conveyor.
FIG.10 is a diagrammatic plan view of a divertor system used according to the
present invention
this showing a main conveyor, associated secondary bottle take-off conveyor
and bottle rejection
table showing in solid a deflector plate of a divertor of the present
invention in its rest position
and, in phantom, at the end of its diverting position extending across the
pathway of the
conveyor for a stream of travelling bottles.
As best seen in FIG. 1 and FIG. 2, a bottle inspection station, generally
designated 10,
comprises a mounting assembly generally designated 12 and an associated
conveyor 14. The
assembly 12 has a main arm consisting of an L beam 1$ having a horizontal
member 20 and a
vertical member 22. Bolted, via bolts 21, to horizontal member 20 are two L-
shaped brackets 24
and 26. As will be discussed in detail below, the vertical arms 25 and 27
thereof carry the
components of the light emitting and receiving elements of the inspection
system.
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Horizontal member 20 also has provision at 28 for a bottle cap detector 30
which is connected
via line 32 to power and signal transmitting means (not shown).
The previously described assembly is attached to and carried by adjusting
mechanism 34. This
comprises a base plate 36 which is carried by a pedestal 38 which, in turn, is
firmly secured by
bolts (not shown) to the floor 40. It may be noted that only a small area is
required to seat the
pedestal foot 39. Turning to FIG. 3 secured to the edges of base plate 36 via
bolts 42 are
vertically upstanding side plates 44 and 46, the latter being provided with
slot 48. A top plate 50
is secured to the upper edges of side plates 44 and 46 via welds 52 thereby
completing a rigid
box-like housing which is securely affixed to the floor 40 via pedestal 38.
Top plate 50 contains
a hole (not shown) and, concentric therewith, a journal bearing 54 secured by
bolts 55.
Extending through the hole and bearing 54 is a shaft 56, the lower portion of
which 57 is
threaded as shown. To the uppermost extremity of shaft 56 is filled a crank 58
having a handle
59, rotation of which rotates shaft 56. Located horizontally in the box-like
housing is a
moveable plate 60 which has a centrally located hole 61 to accommodate the
threaded portion 57
of shaft 56. Affixed to plate 40 and extending upwardly and parallel to shaft
56 are three guide
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rods 62 (only one shown) which are adapted to move vertically through a guide
bore (not shown)
in moving plate 60. The 'three guide rods 62 are spaced apart and form an
isosceles triangle and
provide stability and reduce any possibility for moving plate 60 to quaver.
Moving plate 60
carnes at an edge, a bar (not visible) which is arranged to extend thmugh slot
48 in end plate 46.
The portion of the bar which extends through slot 48 is tapp~ and a washer 64
and a locking
crank 66 are located thereon. Finally, secured to moving plate 40 via bolts 70
is member 20 of
support arm 18.
To adjust the height of moveable plate 60, and thereby arm 18 and items
secured thereto, and in
particular the light detector components, such as emitter 70, photoreceptor
71, their guards 73
locking crank 66 is rotated so as to release moveable plate 60. Subsequently,
rotation of crank
58 results in rotation of shaft 56 whereby moveable plate 60 through rotation
of threaded bar 57
is raised or lowered as desired. Guide rods 62 ensure that moveable plate 60
remains and is
maintained horizontal and that movement is smooth and exact. It may also be
noted that cap
detector 30 is also carried by support arm 18.
Also shown in FIG. 1 is conveyor 14 which carries a line of bottles from a
bottle filler (not
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shown) to a bottle labeller (not shown) at high speed - 920 bottles/minute in
this case. However,
only one bottle 80 is shown located at the inspection station. The location of
the inspection
station is close so that there are no labels especially neck labels, or the
bottles which could
interfere with the light beam. Note that the inspection station assembly, the
combination of
adjusting mechanism 34 and support arm 18 and its attachments are not
connected to the
conveyor assembly but directly to the floor. This ensures that normal movement
or shaking etc.
of the conveyor does not result in movement of the detection device which
could result in the
calibration settings of the beam and receive system being inadvertently
changed.
Refernng again to FIG. 2, there is also shown a fiber optic assembly 70 (IDEC
SA9WTS31)
which is connected via light guides 72 to a laser assembly (IDEC SA1 W-FW2)
not shown. As a
practical matter, the alignment of the laser beam is effected prior to
installing the mounting
brackets and support arm 18 into position in the insp~tion station. In brief,
the fiber optic cable
72 is connected to the laser assembly {not shown) and a voltage of 12-24 volts
DC is applied to
the laser. The emitter end of the cable 72 is then mounted into its associate
bracket member 27
and the amplifier lens is then attached. In fact, the laser beam is
essentially invisible and a led is
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used to achieve the alignment, the laser beam being located in the center of
the led circle. Once
aligned, the fiber optic cable plus amplifying lens can be removed and readily
re-installed when
the bracket assembly has to be installed in the inspection station location at
associated conveyor
14.
SYSTEM OPERATION
The operation of the system may be stated briefly as follows. The arrival of a
bottle 80 at the
inspection station breaks the light beam of trigger 86. The centre of the
trigger is positioned
some three eighths (3/8) of an inch upstream from the centre of the laser
light emitter. This
ensures that the light strikes the centre area of the neck of the bottle as
required by the present
invention. The trigger is also programmed to detect the "back wall" of each
bottle i.e. when the
bottle has left the station and it will not activate the laser assembly again
until it has made that
detection. This ensures that the photodetector can only receive one pulse of
light her bottle and
its decision is based solely on its receiving or not receiving that one
measured pulse of Light.
Breaking of the beam results in a command or prompt being sent to the laser
assembly which is
activated to send a pulse of light to the emitter. As stated the system is
arranged so that the time
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between the break in the trigger beam and the light pulse being emitted
results in the light pulse
striking the bottle along its vertical axis C-C, refer FIG. 5. Previously the
position of the emitter
70 and the light sensor 71 had been set so that the laser beam would be
located at a height above
the conveyor which equates to the desired fill level when a bottle is at the
inspection station. In
other words, on line with or just below the base of the meniscus - line B-B in
FIG. 5. This
equates to the intersection of the desired fill height and the central axis C-
C of the bottle neck
and, in this case, also the bottle. The laser used (an IDEC SAIW-FN2 laser
assembly, obtainable
for IDEC) Corporation of Japan produces a light which is able to travel
through the glass from
which the bottle is made but is absorbed to a significant extent by water
molecules. The
sensitivity of the system is preset so that the beam which passes above the
meniscus - even if it
travels through the liquid film at the edges of the meniscus i.e. the central
base portion thereof is
below the desired level - is not absorbed or "blocked" but is picked up by
receiver 71 and which
counts it as a "no hit". This equates to a determination that the bottle in
question is a low-fill. A
signal is then generated which passes to a bottle rejecter system using a
divertor device (see
below) and the bottle is removed from the stream or line of bottles at the
appropriate location. If,
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on the other hand, the laser beam encounters the base of the meniscus or
therebelow, the light is
absorbed, in effect blocked, does not pass to the receiver 71, which,
consequently, is not
activated. No signal is generated and the bottle in question simply continues
along the conveyor
to the next series of operations e.g. a labeller etc. It may be noted that,
from a practical view
point a found low-fill may not be removed from the line of bottles
immediately.
The following description relates in detail to the preferred bottle deflector
device which in
combination with the detection unit described above, constitutes a separate
aspect of the present
invention. For convenience, the deflector or divertor device is located
downstream of the
labeller. Consequently, this system utilizes a known tracking system, the
Krones "Checkmate"
software, to trace the progress of a found no-fill bottle through the labeller
to the deflector device
downstream of the labeller.
Turning to FIG. 6, this shows a vertical cross-section through a divertor
device of the present
invention secured to an associated bracket assembly. The divertor unit
generally designated 110
comprises an electric synchronous motor 112 (model BLX234A2E000 from Thompson
Industries Inc., Thompson Control Division, 2 Channel Drive, Port Washington,
NY 11058) and
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secured thereto an article deflector member or paddle unit 114, the latter
consisting of a mount
116 carrying a rectangular bottle-contacting plate 118. Note this Plate 118
has a length of about
the diameter of a bottle. Secured to the upper portion of mount 116 by two
bolts (not shown),
which extend up through the base 120, is a clamping collar 122. Collar 122 has
a grub bolt 124
located in internal bore 126, which bolt 124 extends through the collar 122
across slot 128 to
enter and engage its associated nut (not shown) tapped internally in collar
122. Collar 122 is also
provided with a bore 130. The mount 116 is made of a rigid plastic material
namely polyamide
as is the contact plate 118 which has a relatively smooth surface. Plate 118
is secured to mount
116 by friction via joints 119 and 121 (refer FIG. 2B). Mount 116 is, to some
extent, cut-away
to reduce weight. It will be appreciated that the plate material is very rigid
and hard wearing
requiring essentially no maintenance. It needs to be replaced only after a
prolonged period of
use especially compared with the softer pads used in prior out devices. The
length of plate 118 is
about or just less than the diameter of the bottles travelling on the conveyor
148, namely about
69 mm and its height is about 55 mm. It is angled to the vertical - refer FIG.
8A - about 5°, that
angle being exaggerated for clarity.
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As shown especially in FIG. 7A, the paddle unit 114 is adapted to be secured
to the shaft 132 via
bore 130 which is located toward one longitudinal end of the unit 114. This is
for convenience
in this specific embodiment. In other embodiments, it may be preferable to
locate the bore i.e.
the vertical axis about which plate 118 would rotate, in the center part of
unit 114. The design is
chosen to best suit the specific application requirements.
The paddle unit 114 is secured to the drive shaft 132 of motor 112 by locking
collar 122 and
specifically, by tightening grub bolt 134 when motor drive shaft 132 has been
located within
bore 130. Motor 112 is supplied with power and signals from a detection unit
through
connection 134 via power and information transmission lines 135 - refer FIG.
9.
The divertor unit 110 is supported and carried by a bracket assembly generally
designated 136.
This comprises three separate brackets numbered 138, 140 and 142 respectively.
Bracket 138
consists of a plate 144 which is secured to a support member 145 of the
conveyor 148 via bolts
150. Extending from plate 144 are bolts 152 which are adapted to extend
through slots 154
vertical limb 155 of L-shaped bracket 138 and be, secured by nuts 156. These
allow bracket 138
to be vertically adjustable and then locked into place via bolts 152. Bracket
138 also has a metal
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gusset 158 welded to and joining both limbs of the bracket to provide
structural rigidity. Turning
to bracket 140 this is similar to bracket 138 but smaller. One limb 160 is
secured to limb 155 of
bracket 138 via bolts 162 which extend through slots 164 - refer FIG. 9. This
arrangement
allows bracket 140 to move horizontally for adjustment toward and away from
the conveyor 148
and then be locked in the desired location by the tightening of screws 162.
Turning to bracket
142, this is secured to bracket 140 via first bolts 166, their associated
holes through vertical limb
168 of bracket 140 being adapted to receive bolts 166 and allow for some
movement in a vertical
plane. Adjustment bolt 170 is tapped into vertical limb 168 of bracket 140.
These in
combination with bolts 170 provide an adjusting system where limb 143 can
rotate to a limited
extent in a vertical plane and be secured at any position within that range of
rotation. Finally,
motor 112 is secured via bolts 172 to the upper limb 143 of bracket 142. The
divertor unit 110
can be seen attached via bracket assembly 136 to a conveyor 148 in FIG. 9. It
should also be
noted that a section has been omitted from conveyor sidewall 180, and the
plate 118 is located in
that opening 181, approximately in line with the two sections of wall 180
adjacent to and
defining opening 181.
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CA 02392579 2002-07-05
In summary, bracket assembly 136 via the combination of the three individual
brackets 138, 140
and 142 provides for vertical adjustment; horizontal adjustment; and angle
adjustment in a
vertical plant. Since paddle unit 114 is secured directly to motor 112 via
shaft 132, adjustment
of the location and angle of the motor 112 relative to the conveyor 148 also
adjusts the location
and angle of the paddle 114 and in particular, the bottle contacting-plate
118. It has been found
that a small deviation from the vertical of plate 118 assists in maintaining
diverted bottles in an
upright condition as they leave the deflector and move across the conveyor
148. In this
embodiment of the present invention, - refer FIG. 8A - a deviation of about
3° - S° anti-
clockwise from the vertical i.e. the upper corner 119 of plate 118 is closer
to the conveyor path
and hence the line of bottles 174 than the lower corner 121, has been found
preferable. Also
shown in FIG. 8B is the point or edge 117 of the bottle, this being radically
opposite the point
where plate 118 contacts and acts on the bottle 174.
Initially, the bottle when resting on and being carried by the conveyor
because of lubricant
located on the conveyor has a tendency to adhere to the conveyor surface.
Consequently, the
initial contact between corner 119 and the bottle can still result in the
bottle tending to rotate
CA 02392579 2002-07-05
about bottle edge 117 and become unstable and under the influence of the
moving conveyor
leave the deflector unit in an uncontrolled condition. Consequently, in the
shown preferred
embodiment, the plate 118 is angled to the vertical about 5°. It is
believed that this small angle is
sufficient to allow the bottle to rotate in a vertical plane a small amount
which is sufficient to
break the "seal" between the bottle base and the conveyor. Immediately
thereafter, the lower
portion of plate 118 contacts the bottle also and allows the bottle to righten
to maintain control of
the movement of the bottle so that when it leaves the paddle plate 118, it is
in a stable
equilibrium and exits the line and successfully moves to the desired location
be it a receptacle or
another conveyor.
Turning to FIG. 10, this is a diagrammatic plan view of a conveyor system
incorporating the
present invention. A bottle input conveyor 170 is provided with a bottle
inspection device 172
adapted to inspect bottles travelling in a stream on conveyor 170 in the
direction of the arrow. A
deflector device 176 of the present invention is located downstream of
inspection station 172 and
adjacent conveyor sidewall or rail 180. Of deflector device 176, only the
paddle unit 182 is
actually shown (in plan) with bottle contact plate 184 being shown (in solia~
in its base or rest
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CA 02392579 2002-07-05
position generally adjacent, and parallel to conveyor sidewall 180. The
vertical position of
paddle unit 182 relative to the conveyor 170 is set so that upon rotation,
bottle contact plate 184
can swing across the conveyor and make contact with a selected bottle at the
desired position on
the bottle wall - refer FIG. 8A - travelling thereon in the direction of the
arrow. The conveyor
wall 180 at the location of the deflector 176 and, more specifically, adjacent
bottle contact plate
184, is cut away to provide a gap to allow for the rotation of the plate 186
of the paddle unit 182
across the conveyor 170.
Located adjacent and parallel to, conveyor 170, but on the opposite side
thereof to deflector 176,
is a bottle take-off, conveyor 188. On the other side of conveyor 188 is a
bottle receiving table
190 this being located to receive totally unrecoverable rejects. Rotation of
the paddle 182 in an
anti-clockwise direction results in the bottle contact plate 184 moving across
conveyor 180 - the
new position thereof being shown in phantom at 192 contacting bottle 174a.
Also shown in
phantom are previously deflected or rejected bottles 174b and 174c.
As indicated earlier, in the case of the specific synchronous motor BLX234,
the full count is
8000. Since the paddle is mounted on the motor shaft 132, this means that the
paddle member
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CA 02392579 2002-07-05
would rotate 360° an a full count. In this specific case, a 21°
rotation of the paddle which is
required to provide the thrust necessary to move the bottles out of the line
on to the take-off
conveyor is achieved by programming the motor with a count of 525 (525/8000 x
360=21°). The
count of 525 represents the distance from the base or rest position of the
paddle 118 adjacent a
conveyor to its full extension over the conveyor required to effect the
desired rejection of the
bottles. Following completion of the initial rotation, the programmed reverse
rotation
immediately occurs returning the paddle to its original and rest position
outside the pathways this
completing the cycle. The motor cannot respand to another signal, and hence
the paddle cannot
move to reject another bottle, until that cycle is complete. However, the
characteristics of the
motor are such that it is able to complete that cycle extremely rapidly and
sufficient to handle the
high-speed rejection of bottles required by modern facilities. It should be
noted that even with
the high rates involved, the device is able to reject a single bottle even
when the bottles in the
rapidly moving line are in contact with each other. Further, it should also be
noted that even
when adjacent bottles are required to be rejected, the present invention
completes a full cycle in
respect of each bottle. Consequently, each bottle is smoothly removed by the
same sweeping
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CA 02392579 2002-07-05
action and the second and subsequent adjacent bottles in a line to be rejected
do not encounter a
paddle resting in the in pathway. This is important since the synchronous
motor can be
programmed to provide a different rejection action, and thereby controllably
direct even adjacent
bottles to different destinations, in response to it receiving different
signals from a sensing
station. The above calculation is given only for bottles to be moved to the
adjacent conveyor.
The motor parameters required to mane bottles to the 190 or other destinations
can readily be
calculated. Such calculations might require taking into account a different
deflector plate design,
weight etc. but this is readily achieved by simple system tests. Consequently,
say 50 adjacent
bottles are to be rejected - some for absence of crowns; some far being low
fills etc., each can be
dispatched to the correct area for that defect. Articles to be simply sorted
are handled in the
same manner.
Moreover, the two rotational movements in a cycle can be effected at the same
or different rates
of acceleration but in any event, are preferably at a maximum relative to the
motor characteristics
to ensure the cycle is completed as soon as possible and the paddle is in its
rest position outside
of the pathway. For example, in the situation described above for movement to
conveyor 188,
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CA 02392579 2002-07-05
the initial acceleration is at about 38,000 rps and deceleration toward the
stop at about 11,000 rps
for a velocity of b700 rps.
The devices of the present invention have significant advantages over prior
art devices, namely:
(i) simple in construction;
(ii) easily installed requiring minimal scarce space and utilities;
(iii) require little maintenance
(iv) have rapid response times;
(v) the detector device reduces false low-fill calls
(vi) is able to reject or sort articles moving at high speeds for prolonged
periods with no
reduction in efficiency
(vii) is inexpensive
(viii) the detection and sorting device can operate with available deflection
devices but is
advantageously used with the deflection device of the present invention.
