U.S. patent number 3,613,885 [Application Number 04/854,877] was granted by the patent office on 1971-10-19 for bottle label detector-label inspecting and sorting apparatus.
This patent grant is currently assigned to Pfizer Inc.. Invention is credited to Michael J. Bilello, Alfred P. Brooks, Denis O. Rehse.
United States Patent |
3,613,885 |
Rehse , et al. |
October 19, 1971 |
BOTTLE LABEL DETECTOR-LABEL INSPECTING AND SORTING APPARATUS
Abstract
A starwheel turntable abstracts articles from a conveyor and
returns properly labeled objects to it. Inadequately labeled
objects are diverted and segregated. Labels are sensed in an
initial portion of the turntable and accept signals generated
thereby are advanced to the diverter when the articles pass through
an advance triggering device. A verifying reject signal for the
following article is generated when the immediate article is
passing between the triggering device and the diverter. The release
of this reject signal is delayed until after the next article has
time to pass through the advance triggering device and is cancelled
if such next advance triggering is accomplished. This prevents any
article slipping by the signal advancing trigger without actuating
it from being accepted. The reject signal is accordingly held in a
bistable switch long enough to reject the following article if it
does not trigger the advance of its own label detecting signal. The
advance and verifying signals are conveniently triggered by
photoelectric devices. Label detecting is effectively accomplished
for transparent and semitransparent articles by a series of
photoelectric sensing heads having illuminated scanning chambers
past which the articles pass closely adjacent. A label disperses
sufficient light back into the chamber to generate an accept
signal, whereas, the transparent or semitransparent unlabeled wall
transmits the light away without generating a signal.
Inventors: |
Rehse; Denis O. (Long Island
City, NY), Brooks; Alfred P. (Cranbury, NJ), Bilello;
Michael J. (Staten Island, NY) |
Assignee: |
Pfizer Inc. (New York,
NY)
|
Family
ID: |
25319759 |
Appl.
No.: |
04/854,877 |
Filed: |
September 3, 1969 |
Current U.S.
Class: |
209/528; 209/563;
209/919; 209/658 |
Current CPC
Class: |
B07C
5/3412 (20130101); Y10S 209/919 (20130101) |
Current International
Class: |
B07C
5/34 (20060101); B07c 005/34 () |
Field of
Search: |
;209/111.7,73 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Schacher; Richard A.
Assistant Examiner: Church; Gene A.
Claims
We claim:
1. An apparatus for inspecting whether articles are labeled and
sorting them comprising an article-transporting means,
article-diverting means connected to said transporting means for
abstracting unlabeled articles, said article-transporting means
including a track, label-sensing means mounted upon an initial
portion of said track, signal-generating means connected to said
label-sensing means for generating "accept" signals when said
sensing means detects a label upon an article, signal storage means
for holding said "accept" signal while said article is being
traversed along said track, actuating means connected to said
diverting means for causing it to move from article accepting to
diverting positions, said signal storage device being connected to
said actuating means, a signal advance triggering means being
disposed on said track a predetermined distance after said sensing
means, gate means connecting said signal advance triggering means
with said storage device whereby the condition of said storage
device is advanced to said actuating device to position said
diverting means in the "accept" position if said sensing means has
detected a label upon said article, verifying means for said signal
advance triggering means connected to said actuating means, said
verifying means being timed with respect to the passage of articles
along said track for generating reject signals and transmitting
them to said actuating means after said article has passed through
said signal advance triggering means, said signal advance
triggering means being connected to said verifying means for
cancelling reject signals generated thereby in response to
actuation of said signal advance triggering means whereby said
diverting means is maintained in the article-accepting position
when labeled articles are detected and said signal advance
triggering means is actuated.
2. An apparatus as set forth in claim 1 wherein said verifying
means includes verifying triggering and reject signal generating
means said verifying triggering means being disposed on said track
between said signal advance verifying means and said diverting
means, said verifying triggering means being connected to said
reject signal generating means which it triggers to generate a
reject signal, and time delay means connected between said reject
signal generating means and said actuating means whereby a reject
signal generated by the passage of an article is stored a
predetermined time sufficient to allow the succeeding article to
traverse the track past said signal advance triggering means and to
thus cancel said reject signal if said succeeding article actuates
said signal advance triggering means.
3. An apparatus as set forth in claim 1 wherein said label
detecting means comprises a series of label sensing elements for
successively scanning the passage of an article and for generating
at least one "accept" signal if a label is present on said
article.
4. An apparatus as set forth in claim 3 wherein said
article-transporting device is constructed and arranged to rotate
said article past said signal-sensing devices whereby said
label-sensing elements are caused to scan the entire periphery of
said article.
5. An apparatus as set forth in claim 3 wherein said label-sensing
elements are photosensitive devices.
6. An apparatus as set forth in claim 5 wherein said photosensitive
devices comprise a scanning head, said scanning head being disposed
closely adjacent the path of travel of said articles on said track,
an illuminated chamber in said head adjacent the path of travel of
said articles on said track, an outlet port in said illuminated
chamber adjacent said path of travel of said articles, a source of
light in said head connected to said illuminated chamber and
disposed at an acute angle with respect to the side of said
articles passing adjacent said illuminated chamber, a
photosensitive detector connected to said illuminated chamber,
limiting means connected to said photosensitive means, the
threshold of said limiting means being set to generate a signal in
said sensing means when a predetermined amount of light is detected
in said chamber whereby said signal is generated when a
light-reflecting article passes closely adjacent said port and
disperses light back into said illuminated chamber and wherein said
light passes through the transparent wall of said article and out
of said chamber in the absence of a label.
7. An apparatus as set forth in claim 1 wherein said signal advance
triggering means comprises photosensitive means mounted along said
track for actuation by the passage of an article past it.
8. An apparatus as set forth in claim 7 wherein said verifying
triggering means comprises photosensitive triggering means mounted
on a portion of said track between said signal advance triggering
and said diverting means for actuation by the passage of an article
past it.
9. An apparatus as set forth in claim 1 wherein said "accept"
signal generating means comprises electrical switch means.
10. An apparatus as set forth in claim 9 wherein said signal
storage means comprises time delay and reading circuit means, and
said time delay means holding said signal in said storage means
long enough to maintain it available for advance to said actuating
means when said article actuates said signal advance triggering
means.
11. An apparatus as set forth in claim 1 wherein said actuating
means connected to said diverting means comprises electrical memory
and solenoid actuating means.
12. An apparatus as set forth in claim 2 wherein said reject signal
generating means comprises a bistable electronic switching
means.
13. An apparatus as set forth in claim 12 wherein a time delay
means for delaying the release of said reject signal is connected
between said bistable electronic switching means and said actuating
means.
14. An apparatus as set forth in claim 1 wherein said
article-diverting means is biased to the "accept" position.
15. An apparatus as set forth in claim 1 wherein said
article-transporting means comprises a pocketed starwheel and
arcuate track.
16. An apparatus as set forth in claim 15 wherein said track
includes aligned entrance and return sections for abstracting
articles from a conveyor and returning "accepted" articles
thereto.
17. An apparatus as set forth in claim 16 wherein said article
transporting means also includes an exit section connected to said
track, said diverting means being connected between said exit
section and said track whereby rejected articles are removed from
said article-transporting device before they can be returned to
said conveyor means.
18. An apparatus as set forth in claim 17 wherein holding means is
connected to the entrance to said track whereby articles are
delivered one at a time to said starwheel.
19. An apparatus as set forth in claim 15 wherein synchronization
means is provided between said starwheel and said articles being
transported thereby, said synchronization means including starwheel
rotational phase sensing means, starwheel stopping means, said
starwheel rotational phase sensing means being connected to said
starwheel stopping means for stopping its rotation when its pockets
are in position for picking up articles, article-sensing means
mounted on said track where articles are picked up by said
starwheel, and said article-sensing means being connnected to said
starwheel-stopping means for overriding the input from said
starwheel rotational phase sensing means whereby said starwheel is
caused to continue rotation when articles are disposed in positions
for pickup in said pockets.
20. An apparatus as set forth in claim 19 wherein said starwheel
rotational phase sensing means comprises projections on said
starwheel corresponding to the angular phase of said pockets, and
photosensitive means for detecting when said projections are in
positions corresponding to the pickup positions of said pocket.
21. An apparatus as set forth in claim 20 wherein said
article-sensing means comprise photosensitive article-detecting
means.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to apparatus for detecting the presence or
absence of labels on articles (such as containers) and more
particularly relates to such apparatus in which inadequately
labeled objects are sorted out and abstracted from the main stream.
It still more particularly relates to such apparatus which
photoelectrically senses the presence or absence of labels on
transparent or semitransparent containers, especially bottles
containing pharmaceutical products, for which labels are absolutely
required.
2. Description of the Prior Art
Many devices have been developed for detecting whether containers
are adequately labeled and for sorting out unlabeled or
inadequately labeled articles. It is essential in packaging
pharmaceutical goods that no unlabeled container be shipped.
Sensitive devices are, however, prone to reject some properly
labeled containers with the inadequately or unlabeled containers.
Rejecting properly labeled articles is time consuming and costly.
The seriousness of false rejection is apparent when one considers
that the false rejection of even 1 will divert more than two
bottles per minute when the production rate exceeds more than 200
articles per minute. Existing devices also require special inks,
marks or holes on the labels or elaborate positioning systems. An
object of this invention is to provide a relatively simple,
economical and dependable device for determining whether packaged
articles are adequately labeled and for minimizing the rejection of
only those which are improperly or inadequately labeled.
SUMMARY
Labeled objects are advanced in predetermined time sequence along a
conveyor. The sorting means in the path of the conveyor has
"accept" and "reject" positions. A photosensitive sensing means
mounted alongside the conveyor generates "accept" signals if it
detects the presence of a label in a predetermined position and
transmits them to an "accept" signal storage means. A signal
advancing station causes the storage device to transmit the signals
to the sorting means in response to passage of the object through
it. This conditions the actuator for the sorting means to hold it
in the position for accepting objects which have generated "accept"
signals. A verifying means is also provided for insuring that
objects are rejected if they have slipped through the signal
advancing means without actuating it. This double-checking function
is conveniently provided by a time-delayed reject signal generating
means, which is actuated by passage of the object between the
signal advancing means and the sorter. THis signal advancing means
is also connected to the signal rejecting generator for cancelling
the preinserted reject signal. The passage of an object past the
signal advancing means therefore accomplishes two functions.
It advances an accept signal from the sensing means to the sorting
actuating means to maintain it in the accept position for a
properly labeled object. It also cancels the reject signal
generated by the passage of the previous object past the reject
signal generator before its delayed transmission to the sorting
actuator is accomplished. This insures that objects are not
accepted unless they have generated "accept" signals as a result of
sensing properly applied labels and have also actuated the signal
advancing means to transmit the results of the label sensing to the
sorting actuator.
A highly efficient photosensitive detecting device has an
illuminated chamber disposed closely adjacent the path of travel of
articles on the track. A port in the chamber is blocked by the
sides of articles passing close by it. Light-reflecting labels
disperse light back into the chamber to generate signals, whereas
the absence of a label permits the light to pass through the
transparent or semitransparent wall of the article and out of the
chamber.
A starwheel transport efficiently traverses articles in the
aforementioned inspection and sorting path. THe movement of the
starwheel is effectively synchronized with the conveyor by a pair
of photosensitive detectors. One of the detectors is disposed in
the entrance portion of the starwheel transport and the other is
disposed to sense the phase of movement of the starwheel. The
starwheel-detecting device interrupts rotation of the Starwheel
when it arrives at a position to receive an article. The
article-sensing device overrides the starwheel-sensing device to
continue rotation of the starwheel when an article arrives in
position to enter the receiving pocket in the starwheel. This
insures that articles enter each pocket of the starwheel as it
rotates without the danger of a bottle jam-up. Extremely rapid
inspection and sorting can thus be accomplished as a result of the
aforementioned features without accepting inadequately labeled
articles or rejecting more than a bare minimum of properly labeled
articles.
BRIEF DESCRIPTION OF THE DRAWING
Novel features and advantages of the present invention will become
apparent to one skilled in the art from a reading of the following
description in conjunction with the accompanying drawings wherein
similar reference characters refer to similar parts and in
which:
FIG. 1 is a plan view of one embodiment of this invention installed
in conjunction with an article-conveying system;
FIG. 2 is a front view in elevation of the embodiment shown in FIG.
1;
FIG. 3 is a schematic view in elevation of photoelectrical portions
of the embodiments shown in FIGS. 1 and 2;
FIG. 4 is a cross-sectional view taken through FIG. 1 along the
line 4--4;
FIG. 5 is a schematic diagram of electrical control portions of the
embodiment shown in FIGS. 1 and 2;
FIG. 6A is more detailed electrical diagram showing components
incorporated in the diagram shown in FIG. 5; and
FIG. 6B is an electrical diagram of a starwheel synchronization
circuit for use with the apparatus shown in FIGS. 1-6A.
DESCRIPTION OF PREFERRED EMBODIMENTS
In FIG. 1 is shown a label-detecting and article-sorting system 10
mounted along a conveyor 12 of packaged articles 14, such as
bottles of pharmaceutical tablets. Device 10 includes a starwheel
transport 20 revolving within circular rail 22. Starwheel 20
includes three article-receiving pockets 24 for traversing the
articles about the inspection and sorting path in a predetermined
timed relationship. Six sensing devices 26 are mounted in an
initial section of rail 22 for generating an "accept" signal if
they detect the presence of a label 28 (shown in FIG. 2) upon a
bottle 14. Labels 28 are of a contrasting color relative to bottle
14 and are for example white upon a relatively dark bottle.
However, a white label on a clear bottle with a white powder
content is also detectable. Bottles 14 rotate as they are rapidly
traversed by starwheel 20 and more than one detecting sensor 26 is
therefore necessary to insure that an "accept" signal is generated
by each bottle 14 carrying a label 28. The provision of a number of
sensing devices 26 is more economical and rapid than one sensing
device and elaborate bottle-positioning systems. After bottle 14
traverses sensors 26, it goes through signal advancing detector 30
of a photoelectric type for gate 1 later described in detail in
conjunction with FIGS 3-6. Bottle 14 then passes through verifying
detector 32 for gate 2 which conditions the system for rejecting
the following article if it does not actuate the signal advancing
detector 30 for gate 1.
Diversion of unlabeled articles is accomplished by deflector 34
actuated by rotational solenoid 39. Return spring of rotational
solenoid 39 biases deflector 34 to the bottle rejecting or
abstracting position shown in broken outline in FIG. 1.
Electrical actuation of solenoid 39 forces deflector 34 against the
force of the return spring 38 to the retracted or
bottle-"accepting" position shown in full outline in FIG. 1. In the
full-line position deflector 34 allows bottles 14 carried in
pockets 24 to be returned to conveyor 12 through return chute 40.
Bottles 14 abstracted by deflector 34 in the broken-line position
are delivered to exit chute 42 and exit conveyor 44 for discharge
to a reject-collecting station not shown.
FIG. 3 shows photoelectric aspects of the system including sensors
26 and gate detectors 30 and 32. Sensors 26 each include an optical
head 46 mounted in rail 22. Heads 26 include two small intersecting
holes 48 and 50 which are on the order of one-half of 0.10 inch in
diameter, for example 0.040 inch in diameter. Illuminating hole 50
is disposed at an angle a, for example 70.degree., from horizontal
receptor hole 48. Light is delivered to illuminating holes 50 by
fibre optics 52 (glass strands of 0.001 of an inch diameter) which
are connected in a bundle 54 in block 56 mounted on frame 58
containing light source 60 and infrared-absorbing plate 62. The
light delivered through fibre optic 52 passes through hole 50 and a
joint hole 64 in the side of the head 46 adjacent passing bottles
14. If a label 28 passes adjacent joint hole 64, the light
dispersed therefrom is collected in passage 48 and conducted
through another fibre optic 66 to bundle 68 in sensing block 70. A
photosensitive element 72 is mounted at the lower end of optic
bundle 68 for actuation thereby. Photosensitive element 72 may be
any type of photosensitive element such as a phototransistor, a
photodiode or an ordinary photoelectric cell. Phototransistors are,
however, preferred because of their higher sensitivity and speed.
The sensitivity of photosensitive device 70 is governed by
adjusting potentiometer 74, and its output is connected to the
electronic circuit through wires 76.
Gate detectors 30 and 32 are part of photosensitive devices for
detecting the passage of objects. They utilize a fiber optic 52
conducting a beam of light through transmission hole 78 in
channeled gate block 80 for detection by a photoelectric cell 82 in
hole 83 in the opposite walls of block 80. Holes 78 and 83 are
aligned with each other and their centerline 85 is disposed at an
angle below the horizontal, which is for example 7.degree., to
cause the gate-actuating beam to catch bottles which might be
missed or tilted. The passage of an article 14 through the
transmitted beam of light accordingly actuates photoelectric cell
82 in a conventional manner.
FIGS. 5 and 6A show electrical portions of the device in
conjunction with a schematic representation in simplified linear
form of apparatus 10, deflector 34, return chute 40 and exit chute
42. The electrical portions of the device include six
photoelectrical sensors 26 connected to photosensitive element 72
within the block designated sensor A. Sensor A is in turn connected
to connected devices including amplifier B, flip-flop C, time delay
D, reading circuit E, memory F and actuator for solenoid G.
Photosensitive detector 30 is connected to a series of electrical
devices including gate 1 and amplifier H.
Photosensitive detector 32 is connected to a series of devices
including gate 2, amplifier J, bistable flip-flop K and time delay
L. Amplifier H is also cross-connected to reading circuit E and to
bistable flip-flop K.
FIG. 6A shows the components in correspondingly lettered blocks in
FIG. 5. The output of flip-flop C goes through diode 100, used to
charge capacitor 102 which is the timing element of time delay D.
Diodes 104 and 106 are used to prevent the breakdown of the
emitter-base junctions of transistors 108 and 110. Capacitor 112 is
a memory element capacitor. Diode 116 discharges memory capacitor
112 into resistor 118 when transistor 120 is off. Diode 114 has a
leakage current to match that of diode 116. Transistor 122 is a
phase inverter for gate 1. Transformer 124 is used to isolate the
AC line, which is required for proper grounding.
When a bottle enters the sensing area, it can generate from one to
six pulses if it has a label because there are six sensing stations
26 to insure that a signal is generated as the bottle rotates. Such
signal is amplified at B and fed to flip-flop C which is set to a
preselected threshold. The output from flip-flop C is fed to time
delay holding circuit D and a signal is fed to the open switch of
reading circuit E and temporarily blocked from the memory circuit
F.
Meanwhile, the bottle advances to photosensitive detector 30 for
gate 1, where it breaks a photocell beam. This generates a signal
which is amplified at H and fed to reading circuit E, allowing
transmittal to the memory unit F of the signal previously generated
in the time delay circuit. The memory unit directly operates the
actuator for solenoid G, placing it in the open or accept position.
Then the bottle leaves photosensitive detector 30 and removes the
read signal. Between this time and the time the next bottle enters
the sensing area, the time delay by circuit D will elapse. This
will have no effect on the memory because the read signal has
previously been removed.
If the bottle entering the sensing area has no label, no signal
above the threshold is generated by the sensing station A, and the
time delay circuit D is not energized. Thus, there will be no
signal at the input to the reading circuit E, and when the bottle
passes gate 1, giving the reading command, the memory unit F will
be discharged. This now places solenoid G in the reject mode. An
accept signal is always represented by a positive voltage in the
actuator for solenoid G, whereas a reject signal is represented by
a lack of voltage.
Assume that an accepted bottle has placed the solenoid in accept
mode. As a second labeled bottle enters the system, it in turn
generates a signal as before at A, and the same is amplified at B,
accepted by flip-flop C and a time delay signal is generated at D.
The second bottle then proceeds to pass gate 1, providing a signal,
which is amplified to refresh the memory F, and the solenoid G
remains in the accept mode.
This sequence requires further refinement because of the
possibility that a bottle without a label may fail to break the
gate 1 photobeam at detector 30, e.g. if it is tipped on its side.
Thus, there would be no signal at the reading circuit E, no reading
command would be generated at gate 1. Memory F would remember the
previous label and stay in the accept mode, thus potentially
accepting a nonlabeled bottle. This remote possibility is
eliminated by the inclusion of verifying gate 2.
Continuing with the sequence of an accepted bottle which has passed
the sensor and gate 1, the same now passes photosensitive detector
32 for gate 2. Here, a photocell beam is again interrupted,
generating a further signal which is amplified at J and fed into
bistable flip-flop K. The output of K is a reject signal which is
time delayed at L and which will cause memory F to go into the
reject mode. This causes solenoid G to reject if and only if gate 1
does not reset bistable flip-flop K and cancel the reject signal
before the time delay has elapsed.
The entire sequence is now reviewed as it applies to several
bottles passing through the stations. Assuming that bottle No. 1
enters the system, sensor A detects a label. The amplified signal
is fed from B to flip-flop C and in turn to time delay circuit D.
Bottle No. 1 now passes gate 1, providing a signal which is
amplified at H and fed to reading circuit E. Memory F then enters
the accept mode and actuator G for solenoid G goes into the accept
position. Bottle No. 1 now proceeds to gate 2, generating a further
signal, which is amplified at J and fed to flip-flop K. The reject
output from this flip-flop is fed into time delay circuit L.
Meanwhile, bottle No. 2 enters the system, sensor A detects the
label, and the amplified signal is fed from B to C and into the
time delay circuit D. Bottle No. 2 now passes gate 1 and the signal
from this station is amplified and simultaneously does two things:
(a) it resets flip-flop K, cancelling the reject signal before the
time delay at L has elapsed; and (b) it is simultaneously fed to
reading circuit E and memory F remains in the accept mode. Solenoid
G remains in the accept position and thus diverter or deflector 34
is not closed at any time in a normal sequence of labeled
bottles.
Starwheel synchronization device 84 is shown in FIGS. 1 and 2 and
electrical components thereof are shown on FIG. 6. Synchronization
device 84 includes photosensitive gate 3 shown in FIG. 1 in
position to detect an article 14 in an initial portion of device
10. Gate 3 includes a photosensitive detector 86 similar in
structure to detectors 30 and 32 for gates 1 and 2. When an article
14 has entered within photosensitive detector 86 for gate 3 as
shown in FIG. 1, it is in position to be received within
article-receiving pocket 24 in starwheel 20.
Gate 4 is mounted under rail 22 in position to detect the phase of
rotation of shaft 88 of starwheel It senses such phase of rotation
by sensing the position of one of three tabs 90 extending at angles
120.degree. relative to each other from shaft 88 to correspond to
the relative angles of pockets 24 in starwheel 20. Gate 4 includes
sensing means 92 similar to aforementioned photosensitive detecting
means 30. 32, and 86. Gates 3 and 4 are connected as shown in FIG.
6A to the starwheel synchronization circuit 94 which is described
in detail in FIG. 6B.
Diode 130 prevents the 40 -volt signal from feeding into the 5
-volt supply. Transistor 126 feeds a precise voltage into the
timing unit of the flip-flop. Transformer 128, having a 36 -volt AC
and a 5 -volt AC output, is the AC source for the two power
supplies.
FIGS. 1 and 2 show the components of the electrical circuit for
accomplishing the following functions gate 3 senses if a bottle is
in the proper position to be picked up by the wheel. If it is,
starwheel 20 continues uninterrupted; but if it is not, then
synchronization solenoid operated clutch and brake 96 stops
starwheel 20 at a given point determined by gate 4. When a bottle
14 does get to the proper position, synchronous clutch and brake 96
drops out and allows the wheel to continue. The pause in operation
occurs at a time when the system is not sensitive to a delay.
Synchronization solenoid-operated clutch and brake 96 is activated
with a higher than normal voltage to insure fast, positive pull in
which is then lowered to permit continuous operation.
Synchronization of starwheel 20 takes place when synchronous
solenoid-operated clutch and brake 96 is activated to stop the
rotation of the starwheel three times when the photoelectric beam
of gate 4 is interrupted. The signal to activate synchronous clutch
and brake 96 from gate 4 is overridden when gate 3 senses a bottle
14 is completely entered within the starwheel transport slot ready
for transport. At this point, the signal of gate 4 to synchronous
clutch and brake 96 is overridden, resulting in the deactivation of
the synchronous solenoid, and allowing the starwheel to rotate. The
electrical circuitry for accomplishing these functions is shown in
FIG. 6B.
Sorting system or apparatus 10 thus operates at an extremely fast
rate of speed with remarkable efficiency. It does not pass any
inadequately labeled items even at article transport rates of over
200 bottles per minute. It falsely rejects only 0.1 percent even at
these high rates of speed. In so doing it does not require any
special inks, markings or critical positioning of bottles or
labels.
* * * * *