U.S. patent application number 11/272149 was filed with the patent office on 2007-05-17 for bottle filling machine with sensor and method thereof.
This patent application is currently assigned to SIDEL and PRESSCO TECHNOLOGY INC.. Invention is credited to Don W. Cochran, Andrea Lupi, Franco Mutti, Roberto Schianchi.
Application Number | 20070107801 11/272149 |
Document ID | / |
Family ID | 38039508 |
Filed Date | 2007-05-17 |
United States Patent
Application |
20070107801 |
Kind Code |
A1 |
Cochran; Don W. ; et
al. |
May 17, 2007 |
Bottle filling machine with sensor and method thereof
Abstract
A filling apparatus and method including a carrier for
transporting containers and having a plurality of valves, each of
the valves being opened for an individual, specific period of time
to control a flow of liquid into the respective containers, while
the containers are transported by the carrier. An exit feed path
transports the containers after the containers have been filled,
and a sensor, such as a camera, detects a level of liquid in the
respective containers, while the containers are on the exit feed
path. The sensor produces a signal that is stored as data
representing the level of liquid for the individual containers. The
data is then tracked and used for valve optimization. A period of
time that each individual valve is opened for subsequent fillings
is adjusted based on the signal and the historical performance of
each valve.
Inventors: |
Cochran; Don W.; (Cleveland,
OH) ; Schianchi; Roberto; (Octeville sur Mer, FR)
; Mutti; Franco; (Octeville sur Mer, FR) ; Lupi;
Andrea; (Octeville sur Mer, FR) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W.
SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
SIDEL and PRESSCO TECHNOLOGY
INC.
|
Family ID: |
38039508 |
Appl. No.: |
11/272149 |
Filed: |
November 14, 2005 |
Current U.S.
Class: |
141/153 |
Current CPC
Class: |
G01F 13/006 20130101;
G01F 23/292 20130101; B65B 57/145 20130101; G01F 23/20 20130101;
B65B 3/36 20130101; B67C 3/007 20130101 |
Class at
Publication: |
141/153 |
International
Class: |
B65B 43/42 20060101
B65B043/42 |
Claims
1. A filling apparatus, said filling apparatus comprising: a
carrier for transporting containers; a plurality of electrically
controllable valves, each of which is opened for a period of time
to fill a first group of said containers respectively with a
liquid, while said containers are transported by said carrier; an
exit feed path which conveys said containers after said containers
have been filled; and at least one sensor which detects a level of
liquid in said containers, while said containers are on said exit
feed path, such that said sensor produces respective signals which
represent the level of liquid in each said first group of
containers, wherein said plurality of electrically controllable
valves are configured so that the period of time that said
plurality of electrically controllable valves are individually
opened is adjusted for subsequent fillings based on said signals
corresponding to said first group of said containers.
2. The filling apparatus of claim 1, wherein said electrically
controllable valves are electric servo valves which allow control
that provides more than two filling speeds.
3. The filling apparatus of claim 1, wherein the plurality of
valves are provided to correspond to individual ones of said
containers, such that said sensor monitors said containers on said
exit feed path and produces data representing past performances of
each of the plurality of said valves, which is used to determine
individually the period of time that the plurality of valves each
remain open for the subsequent fillings.
4. The filling apparatus of claim 1, wherein said at least one
sensor is a stationary camera and a respective illumination source
positioned to observe said containers in said exit feed path, and
said exit feed path is a path that the containers, which have been
filled, follow after filling and after the valve has been shut
off.
5. The filling apparatus of claim 1, wherein said sensor
communicates with a processor which receives said signals and
controls said period of time that each of said plurality of
electrically controllable valves are kept open.
6. The apparatus according to claim 1, further comprising an
entrance feed path that leads said containers to said carrier, and
at least one auxiliary sensor positioned adjacent to said entrance
feed path to observe said containers while on said entrance feed
path, said auxiliary sensor is operative to determine a volumetric
capacity of said containers before said containers are disposed on
said carrier for filling.
7. The apparatus of claim 6, wherein information pertaining to said
volumetric capacity is utilized to initially determine the period
of time individually that each of said electrically controllable
valves remain open.
8. The filling apparatus of claim 1, wherein said electrically
controllable valves provide a period of high flow and a period of
low flow, such that at least one of said period of said high flow
and said period of low flow is adjusted based on said signals.
9. The filling apparatus of claim 4, wherein the illumination
source is comprised of solid state devices and is equipped to
produce more than one wavelength.
10. The filling apparatus of claim 1, wherein the level of liquid
in multiple containers, filled by one of said electrically
controllable valves, is detected by said sensor before adjusting
said period of time that said one of said electrically controllable
valves is opened, even when the levels of liquid are not consistent
between said multiple containers.
11. The filling apparatus of claim 1, further comprising: one of an
encoding device and a detection sensor that facilitates associating
the containers respectively to said valves, so that fill level data
of each of said valves can be tracked over a period of time,
wherein said period of time that said valves are opened for the
subsequent fillings, is adjusted based on said tracked fill level
data.
12. The filling apparatus of claim 1, wherein said sensor obtains
data from said plurality of containers to provide historic data for
said valves, such that a performance trend of each of said valves
is provided to predict future performance of said valves.
13. The filling apparatus of claim 5, wherein said processor
utilizes an algorithm to determine whether said electrically
controllable valves should be adjusted.
14. The filling apparatus of claim 5, wherein said processor
utilizes an algorithm to determine at least one of how, and how
much to adjust the period of time that said valves are opened.
15. The filling apparatus of claim 1, further including a timing
device which regulates said period of time that each of said valves
remain open so as to fill a predetermined amount of said liquid
into said containers, said timing device being capable of being
periodically updated to new regulation times based on signals from
said at least one sensor.
16. The filling apparatus of claim 12, wherein additional data
besides the level of liquid is used to predict the future
performance of each of said respective valves.
17. The filling apparatus of claim 16, wherein said additional data
includes at least one of temperature of the liquid, pressure of the
liquid, ambient temperature, container mass, container shape,
container wall thicknesses, container volume, liquid flow rates,
machine speed, and valve current.
18. The filling apparatus of claim 1, wherein said carrier is
rotatable.
19. The filling apparatus of claim 6, wherein said at least one
auxiliary sensor is an electronic camera.
20. The filling apparatus of claim 1, wherein said at least one
sensor senses levels of liquid in a plurality of said containers
simultaneously.
21. A method of adjusting an amount of liquid that flows into a
plurality of containers, the method comprising: transporting the
containers by a carrier; flowing liquid respectively through a
plurality of filling valves into the containers; controlling an
amount of liquid that flows into the containers while the
containers are transported by the carrier, the amount of liquid
being controlled by electrically opening the plurality of filling
valves for a predetermined period of time; conveying the containers
along an exit feed path after the containers have been filled;
sensing a level of liquid in the containers while the containers
are on the exit feed path to produce signals which represent the
level of liquid in the containers, respectively; and adjusting the
predetermined period of time that each of the plurality of filling
valves remain open for subsequent fillings based on the
signals.
22. The filling method of claim 21, further comprising: obtaining
information pertaining to the level of liquid in a first group of
the containers, filled by a first of said plurality of filling
valves, to control the period of time that liquid flows into
containers that are to be filled subsequently; and obtaining
information pertaining to the level of liquid in a second group of
the containers, filled by a second of said plurality of said
filling valves, to control a period of time that liquid flows into
containers that are to be filled subsequently by the second filling
valve.
23. The filling method of claim 21, further comprising collecting
data which separately represents the level of liquid provided by
each of the separate valves; and determining the period of time
that each of the valves respectively remain open for subsequent
fillings based on the data.
24. The filling method of claim 21, further comprising providing at
least one stationary electronic camera to perform said sensing.
25. The filling method of claim 21, further comprising providing a
processor to receive the signals and control the period of time
that the liquid flows into each of the containers.
26. The method of claim 21, further comprising: providing an
entrance feed path that leads the containers to the carrier, and
observing the containers while on the entrance feed path to
determine a volumetric capacity of the containers before the
containers are filled.
27. The method of claim 26, further comprising initially
determining the period of time that the liquid flows into the
containers respectively based on at least one of the volumetric
capacity and historical data of the filling valves.
28. The method of claim 21, further comprising providing a period
of high flow of the liquid into the containers and providing a
period of low flow of the liquid into the containers, and adjusting
the period of the low flow based on the signals.
29. The method of claim 21, further comprising providing a period
of high flow of the liquid into the containers and providing a
period of low flow of the liquid into the containers, and adjusting
the period of the high flow based on the signal.
30. The method of claim 21, further comprising detecting the levels
of liquid in multiple containers filled by a corresponding one of
the plurality of valves before adjusting the period of time that
the corresponding valve remains open, even when the levels of
liquid are not consistent between the multiple containers.
31. The method of claim 23, further comprising: correlating the
containers to the valves which respectively provided the flow of
the liquid into the containers, tracking historical data pertaining
to the level of liquid in the containers over a period of time, and
as required, adjusting the time that each of said plurality of
valves remains open based on the historical data which is
tracked.
32. The method of claim 31, further comprising predicting future
flow rates of the liquid through each of the plurality of valves
based on the historical sensor data which is tracked.
33. The method of claim 25, further comprising utilizing an
algorithm to determine whether the period of time that each of the
plurality of valves stays open should be adjusted for subsequent
fillings.
34. The method of claim 25, further comprising utilizing an
algorithm to determine how much to adjust the period of time that
each of the plurality of valves remains open.
35. The method of claim 21, further comprising obtaining additional
data, besides the liquid level, to predict when and how much to
adjust the period of time respectively that the plurality of valves
remain open for subsequent fillings.
36. The method of claim 35, wherein the additional data includes at
least one of temperature of the liquid, pressure of the liquid,
valve current signature, ambient temperature, container
temperature, container mass, container shape, container wall
thickness, container volume, liquid flow rates, machine speed, and
fill reservoir levels.
37. The method of claim 21, wherein the containers are rotatably
transported by the carrier.
38. The method of claim 21, further comprising sensing the levels
of liquid in more than one of said plurality of containers
substantially simultaneously.
39. A filling apparatus, said filling apparatus comprising: a
carrier for transporting containers; means for electrically
controlling a period of time that liquid flows into said
containers, while said containers are transported by said carrier;
an exit feed path which conveys said containers after said
containers have been filled; and means for sensing a level of
liquid in said containers while said containers are on said exit
feed path, such that said means for sensing produces a signal which
represents said level of liquid, wherein said period of time is
adjusted for subsequent fillings based on said signal.
40. The filling apparatus of claim 39, wherein information
pertaining to said level of liquid in a first group of said
containers is obtained by said means for sensing to electrically
adjust the period of time that liquid flows into said containers,
and wherein information pertaining to said level of liquid in a
second group of said containers is obtained, said second group of
containers being filled by a second means for electrically
controlling flow, and is used to adjust a period of time that
liquid flows into said second group of containers.
41. The filling apparatus of claim 39, wherein said means for
sensing communicates with a processor which receives said signal
and controls said period of time for subsequent fillings.
42. The apparatus according to claim 39, further comprising an
entrance feed path that leads said containers to said carrier, and
a second means for sensing positioned adjacent to said entrance
feed path to observe said containers while on said entrance feed
path, said second means for sensing is operative to determine a
volumetric capacity of said containers before said containers are
filled to determine an initial period of time that liquid is to
flow into said containers.
43. The filling apparatus of claim 39, wherein said level of liquid
in multiple containers is detected by said means for sensing before
adjusting said period that liquid flows into said containers, even
when the levels of liquid are not consistent between said multiple
containers.
44. The filling apparatus of claim 39, wherein said means for
sensing obtains data from a plurality of containers that were each
filled by said means for controlling to provide historic data, such
that a performance trend of said means for controlling is monitored
and used to predict future performance of said means for
controlling.
45. The filling apparatus of claim 1, wherein the sensor detects
the level of liquid in said containers by determining respective
weights of said containers, which are filled.
46. The filling method of claim 21, wherein the sensing comprises
determining respective weights of said containers, which are
filled.
47. The filling apparatus of claim 39, wherein said means for
sensing senses the level of liquid in said containers by
determining respective weights of said containers, which are
filled.
48. The filling apparatus of claim 2, wherein said servo valves
allow for an adjustment of a filling speed profile during a filling
period.
49. The filling apparatus of claim 1, wherein a processor is
provided with a memory that includes an algorithm using at least
mathematical statistics including mean and standard deviation
calculations to determine when and how much to adjust the timing
for each of the plurality of valves, and to measure a sample size
for estimating the reliability of a sensor, which performs said
sensing.
50. The method of claim 33, wherein the algorithm uses mathematical
statistics including at least one of mean and standard deviation
calculations to determine when and how much to adjust the timing
for each of the plurality of valves, and a calculated sample size
for estimating the reliability of a measuring sensor, which
performs said sensing.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] Apparatuses and methods consistent with the present
invention relate generally to regulating the dispersion of liquid
into a container. More specifically, the invention relates to
detecting a level of the liquid in the container, so as to obtain
data and appropriately adjust a valve used to regulate the flow of
the liquid.
[0003] 2. Description of the Related Art
[0004] In general, the bottling of beverages, sauces, liquid
spices, etc., requires adjusting the bottling amount within a
predetermined range. For example, it is known to regulate an amount
of flow into a container using cam actuated filling valves, wherein
containers are conveyed along circular path on a carrier, while
being filled via nozzles that direct fluid or other material
contents downwardly into the containers. In such a configuration, a
carousel rotates to move the nozzles synchronously with the passing
containers and the cam moves the nozzles downwardly to engage
against or near the containers. Correct positioning with respect to
a container and the rotational location of the carousel causes the
filler to discharge into the container. However, such a cam
arrangement is susceptible to various types of mechanical wear and
misadjustment leading to inaccurate or inconsistent filling levels.
In addition, a skilled technician is needed to adjust, maintain,
and calibrate a substantial number of cam operated devices, which
can result in increased costs, lower productivity, and increased
labor. Stopping to make such mechanical adjustments or to change to
a new filling job also contributes to additional down-time on the
filling line, which is very expensive in terms of lost
production.
[0005] It is also known in the industry to use so-called electric
valve filling machines. In such machines, the filling valves are
actuated electrically instead of mechanically. In most such
machines, the valve is triggered or controlled electrically while
an actual motive force for moving the valve into the actuated
position is performed pneumatically. In most cases, the air
pressure is used to overcome a mechanical spring pressure in order
to open the valve. When the air pressure is exhausted, the spring
returns the valve to its closed position. To gain the long term
filling consistency that is required in the market, most such
machines rely upon an electronic flow control sensor to verify that
the correct amount of liquid has passed through the valve and into
the container such that the valve can then be closed. Conventional
electric valve filling machines have incorporated either volumetric
flow sensors or mass flow sensors, depending on the type of liquid
material being filled into the containers and which technology is
appropriate for sensing the particular liquid. Typically, an
electronic flow sensor is used at each valve. Because the flow
sensors are relatively expensive, it becomes a substantial expense
to build machines that have the same number of costly flow sensors
as filling valves.
[0006] In addition, apparatuses and methods have been proposed for
detecting and controlling an amount of liquid during the filling
process. For example, U.S. Pat. No. 5,427,161 discloses to fill
bottles by sensing an appropriate time to shut a filling valve by
using a camera to provide image based monitoring of a container.
The camera provides image data of the container while it is being
filled and, on the basis of the observed image data, a computer
determines, in real-time, when to stop filling each container.
However, this process requires a complex, close integration between
the camera's findings and the valve control electronics to effect a
precise shut-off. In addition, because the camera is actually
viewing the containers as they are being filled, turbulence is
induced during the imaging period. If the turbulence is not
consistent or the system is lacking a means to correct for the
turbulence, such image based monitoring could vary and be
inaccurate. Also, the camera is not infinitely fast and must snap
images periodically. Even with present day cameras, there is an
amount of inaccuracy due to factors such as, illumination levels,
camera scan speed, image transmission rate, band-widths, image
analysis time, and other latencies that necessarily occur inside a
computer driven imaging system. This type of system must, by
definition, have a large field of view so it can take multiple
images while the container passes through the field of the camera's
view so the system can interpolate between the images to determine
when the valve should close. The inherently larger field of view
reduces systemic resolution since the number of pixels in the
camera is spread over a larger view area. The container is
inherently viewed from different angles for each image snap which
has a detrimental effect on the quality of the image. In effect,
prior systems require a larger or specially adapted light source,
eliminate the ability to have an optimum view angle and require
hardware and/or software to do additional algorithmic work to
account for turbulence and differences in the scene.
[0007] It is also known to use a partial scan from a camera in
order to reduce the time necessary to take the image and improve
accuracy. However, measurements from the image are still limited by
the speed of the camera and require high speed electronic
"hand-shaking" with valve control electronics, such that the system
will not tolerate any level of indeterminacies in the time that
elapses from the initial image capture to sending a valve shut-off
signal, resulting in increased expense and complexity.
SUMMARY OF THE INVENTION
[0008] Illustrative, non-limiting embodiments of the present
invention overcome the disadvantages described above and other
disadvantages. Also, the present invention is not required to
overcome the disadvantages described above and the other
disadvantages, and an illustrative, non-limiting embodiment of the
present invention may not overcome any of the disadvantages.
[0009] An exemplary aspect of present invention is to provide a
filling method and device that is capable of adjusting flow amounts
based on monitoring current and/or past filling levels. It is an
additional aspect to provide a filling method and device which
could be augmented by other sensory inputs, besides the fill
levels, to improve filling performance.
[0010] An exemplary embodiment of the present invention provides a
filling apparatus including a carrier for transporting containers
and at least one valve which is opened for a period of time to
control a flow of liquid into the containers while the containers
are transported by the carrier. The invention may be implemented in
machines that have more than one valve, but it can be practiced
with as few as one valve. In general, typical rotary filling
machines may have from 20 to 180 valves, with the higher speed and
higher production machines utilizing the larger numbers of
valves.
[0011] An exit feed path can be used to convey the containers after
the containers have been filled and a sensor subsystem detects a
level of liquid in the containers, while the containers are on the
exit feed path, such that the sensor produces a signal which
represents the level of liquid and corresponds to each respective
filling valve. A period of time that each valve is opened for
subsequent fillings may be adjusted based on one or more such
historical measurement signals.
[0012] In further accordance with the invention, information
pertaining to the level of liquid in a first group of the
containers is obtained by the sensor to adjust the period of time
that the valve remains open, and information pertaining to the
level of liquid in a second group of the containers, filled by a
second valve, is obtained to adjust a period of time that the
respectively associated second valve remains open.
[0013] A further exemplary aspect of the invention provides a
plurality of valves that are disposed to correspond to individual
ones of the containers, such that sensor devices monitor the
containers on the exit feed path and produce data representing past
performances of each respective valve of the plurality of valves,
which is used to determine the period of time that the plurality of
valves respectively remain open for subsequent fillings.
[0014] An additional exemplary aspect of the invention includes an
entrance feed path that leads the containers to the carrier, and at
least one additional sensor positioned adjacent to the entrance
feed path to observe measured data about each container while on
the entrance feed path. The additional sensor is operative to
determine a wide range of features, such as, for example,
volumetric capacity of the containers, container type, and
container temperature before the containers are disposed on the
carrier. It can also be used to detect flaws in the containers
which may adversely affect the filling operation. Information
pertaining to the volumetric capacity or temperature may be
utilized to initially determine the period of time that the valve
or respective valves remain open.
[0015] It is also contemplated that an exemplary embodiment of the
invention includes a plurality of valves to fill the containers,
and an encoder that provides a signal stream that allows
correlating the containers to the respective valves, so that
historical fill level data and performance characteristics of each
valve can be logged and tracked over a period of time. The period
of time that the valves are opened for subsequent fillings is
accordingly adjusted based on the fill level historical data. The
sensor may obtain data from a plurality of containers that were
each filled by the corresponding valve to provide historic data,
such that a performance trend of the valve is provided to predict
future performance of the valve. Further, additional data, besides
the level of liquid, may be used to predict and adjust the future
performance of the respective valves.
[0016] In accordance with an additional exemplary embodiment of the
invention, a method of adjusting an amount of liquid that flows
into a plurality of containers is provided, including transporting
the containers by a carrier and flowing liquid into the containers
through a filling valve. An amount of liquid that flows into the
containers is controlled while the containers are transported by
the carrier. The amount of liquid is controlled by regulating a
period of time that the filling valve remains open for flow. The
containers are conveyed along an exit feed path after the
containers have been filled, and a level of liquid in the
containers is sensed while the containers are on the exit feed path
to produce a signal which represents the level of liquid.
Accordingly, the period of time that the valve remains open for
subsequent fillings is adjusted based on the signal.
[0017] An additional exemplary embodiment of the invention provides
a carrier for transporting containers and means for controlling a
period of time that liquid flows into the containers, while the
containers are transported by the carrier. An exit feed path is
provided which conveys the containers after the containers have
been filled. The exit feed path may include the last portion of the
rotary travel of the carrier after filling as well as a run-out
conveyor or another rotary or linear carrier that transports the
just filled container along its path to or through a subsequent
machine or material handling operations. Also included is means for
sensing a level of liquid in the containers while the containers
are on the exit feed path, such that the means for sensing produces
a signal which represents the level of liquid. Accordingly, the
period of time is adjusted for subsequent fillings based on the
signal.
[0018] An exemplary feature of the invention is the elimination of
volumetric flow or mass flow control sensors at each individual
valve. Such flow or mass control sensors dedicated to each valve
are expensive and, in accordance with the present invention, can be
replaced by a valve that opens and closes based on a timing recipe,
rather than a sensor that actually measures a volumetric fluid
amount. This is an economical advantage because flow control
sensors are relatively expensive and the more sophisticated mass
flow sensors are even more costly. Therefore, the present invention
is able to eliminate the flow sensors in favor of another
technology which can potentially provide additional functionality
and substantial cost savings.
[0019] The integrated sensing and filling system of the present
invention may not only replace the basic function of the flow
control sensors, but can be implemented to provide other
inspections that are also useful. For example, an exemplary
embodiment of the sensing system can provide inspection for cap
placement, cap integrity, tamper-band integrity, label presence,
and similar inspections, as part of its extended functionality.
[0020] An additional feature of the present invention reduces an
occurrence of a single anomaly that causes an incorrect valve
setting change. This is accomplished by looking at a statistically
significant number of measurements before a change is made in a
timing recipe or a filling time period. By looking at enough filled
bottles to provide a statistically significant sampling, the mean,
standard deviation and statistical trends for each valve can be
determined with a high confidence level and the system can then
correct the timing recipe accordingly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The above aspects and features of the present invention will
become more apparent by describing in detail exemplary embodiments
thereof with reference to the attached drawings, in which:
[0022] FIG. 1 is a top view of a liquid filling machine and sensor
according to an exemplary embodiment of the invention;
[0023] FIGS. 2a and 2b are cross sections of exemplary valves taken
along line A-A of FIG. 1;
[0024] FIG. 3 is a schematic representation of a machine vision
sensing configuration, according to an exemplary embodiment;
[0025] FIG. 4 is a schematic representation of a machine vision
sensing configuration, according to another exemplary
embodiment;
[0026] FIG. 5 is a schematic representation of a machine vision
sensing configuration, according to a further embodiment;
[0027] FIG. 6 is perspective view showing a sensor and a plurality
of containers according to an exemplary embodiment of the
invention;
[0028] FIG. 7 is a flow diagram representing a method according to
an exemplary embodiment of the invention; and
[0029] FIG. 8 is a flow diagram representing a further method
according to an exemplary embodiment of the invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION
[0030] FIG. 1 is a top view of a filling machine 10 having a
rotatable carrier or carousel 12 for transporting containers 14. A
wide variety of containers may be used in the present apparatuses
and methods, such as glass, plastic, metal, paperboard or the like.
For example, the apparatuses and methods may be used to measure
liquids or granular solid materials, such as fine chemicals,
pharmaceuticals or foodstuffs, or materials comprising solids
suspended in liquids. The containers themselves can also vary
widely in size and shape and may have the form of, for example,
drums, carboys, flasks, cartons, jars, cans, and bottles. However,
an exemplary embodiment of the present invention is intended for
use with containers containing liquids and, accordingly, the
detailed description of the processes hereinafter will mainly be
with reference to such bottles of liquid, since the necessary
modifications of the apparatus and method for use with other types
of containers and contents will be readily apparent to those
skilled in the container handling and filling art.
[0031] The incoming containers 14 move on an input path or conveyor
18 and are picked up by the carrier 12 in a traditional manner,
such as a feed star wheel. Electrically controllable valves 20 are
positioned above the carrier 12 to regulate the flow of liquid into
the containers 14 based on a filling recipe and remain with the
containers 14 while they are rotated around a center vertical axis
in either a clockwise or a counter-clockwise direction by the
carrier 12. As used herein, the term "recipe" may represent a
timing configuration use to regulate flow of fluid into the
containers 14.
[0032] It will be appreciated that the carrier 12 can rotate in any
direction depending on the device's configuration and manufacturing
plant layout considerations. FIGS. 2a and 2b show exemplary valves
20a and 20b which are consistent with the present invention. Valve
20a is used with products that do not include carbonation and do
not directly contact the containers 14. Valve 20b is suitable for
use with carbonated products and includes a sealing device 21 that
contacts the containers 14 and maintains pressure between a nozzle
of the valve 20b and the containers 14. The containers 14 are
positioned to have their open tops facing up toward the filling
valves 20a and 20b, such that the valves 20a and 20b are located
above the containers 14 and are axially aligned with the containers
14 for the purpose of filling in a conventional manner.
[0033] The valves 20a and 20b are typically brought into intimate
contact with containers 14 or to a position very close to the
containers 14 by a rotary cam operated mechanism so that an
accurate timing can be provided for a wide range of containers that
may be filled by the machine. The valves 20a and 20b fill the
containers 14, via a conduit 22 that supplies the product, on the
basis of a precisely controlled elapsed time for each filling valve
20a and 20b. Compressed air is introduced through an input 25 and
is used to move internal plungers of the valves 20a and 20b to
start and stop the flow of the product. The valves 20a and 20b in
general may be electrically controlled through solenoid valves,
while being air actuated.
[0034] The valves 20 do not necessarily need to be electric valves
in order to practice the present invention. However, the valves 20
should be electrically "controllable" in some form to provide a
practical application. Alternatively, the valves 20 could be
electric or hydraulic servo controlled and may have an infinite
amount of fill flow rate adjustment that provides for a wide range
of filling rate profiles. The valves 20 could also take the form of
an electrically or servo adjusted cam, driving a mechanically
operated valve, such that the valves 20 can respond to electrically
communicated changes for adjusting the cam timing periods, cam
actuation shapes, or the cam durations.
[0035] In an exemplary embodiment, two-position conventional
electrical solenoid-operated valves are utilized. Such valves 20
will usually have a high flow position and a low flow position and
each position may have its own solenoid operation coil. While being
filled, the containers 14 pass through a high flow rate section 23
and a low flow rate section 24. The times that the respective
valves 20 are open for high speed filling and low speed filling are
adjusted by sensing previous fill levels and utilizing the valves'
20 respective electronics and software on the basis of each valves'
20 historical performance, current sensing data, and trending. As
will be appreciated, the flow rate could alternatively be such that
it continuously increases from its beginning to end.
[0036] An electronic timing device associated with the valve
configuration may be used to shift the valve from the high volume
flow position to the low volume flow position, such that the high
volume flow and low flow volume are maintained for a predetermined
amount of time, and can trigger an end to the flow to complete the
filling procedure. There may be a separate elapsed time for the
high volume filling section 23 and a separate elapsed time for the
low volume section 24. The elapsed time that the valve 20 is opened
may only need to be periodically adjusted in accordance with the
results of the detected liquid levels. Alternatively, the valve
recipe may be defined and controlled on the basis of encoder ticks
or precise rotary positioning if this application provides an
advantage for a particular implementation of the invention. With
such an implementation, the rotational speed (radians per second)
of the filler carrier should be monitored and controlled more
precisely for satisfactory results.
[0037] When it is detected that a sufficient amount of fluid has
been supplied at the high flow rate, the valves 20 are shifted by
an electronic control device to a second or slow fill position. The
electronic control device could range from a dedicated electronic
board that is located near the respective valves 20, for a fast
response, to a conventional programmable logic controller (PLC),
which has been configured to perform this function, as discussed in
more detail below. Various configurations can be utilized
including, for example, controlling multiple valves 20 with a
single PLC. Careful configuration control should be adhered to so
that the PLC based control architecture and software can maintain
timing precision and repeatability that will yield satisfactory
filling results consistency. This can vary substantially based on
the machine design, speed of filling, and the systemic
responsivity.
[0038] The valves 20 may be dual conventional solenoid coils or a
double wound coil, for example. Each coil portion of the solenoid
is fed an electrical current to actuate the solenoid to each of the
valves' two positions. As the valves 20 are electrically shifted to
the second position, they throttle flow at the slow pace for a
duration around the carousel 12 and, as the containers 14 near
their proper fill level, the valves 20 provide the flow at a more
precisely controlled slow pace in the low flow rate section 24.
[0039] In an exemplary embodiment, the "on" point to open a valve
20 may be set to start at a precise time while the container is in
the high volume flow section 23 and the "off" point may be in the
low volume fill section 24. The particular on/off instructions may
be calculated by algorithms stored in a computer, which are chosen
to optimize the filling times to produce accurate amounts of fluid
in the containers 14. The variables used by the algorithms are
based on the liquid levels of the filled containers 14 so that
subsequent filling amounts can be calibrated.
[0040] After the valves 20 are shut off completely, they will
usually retract smoothly by a rotary cam operated mechanism from
their intimate filling position with the containers 14. The filled
containers 14 will generally exit the filling section and enter a
capper or seamer section to have an appropriate type of closure
installed, depending on the container style.
[0041] A sensor or camera 28, which is discussed in more detail
below, is provided along an exit feed path "B" to form part of a
vision based sensing system that captures an image of each
container 14 which has excited the carrier 12, to determine a level
of liquid in the containers 14, as they move along, or are stopped
on, a conveyor 26. It will be appreciated that the exit feed
monitored by the camera 28 may include the area B through the
latter portion of the rotary travel of the carrier 12 after
filling, as well as the conveyor 26, or other run-out conveyor or
another rotary or linear carrier that transports the just filled
container along its path to a subsequent machine or material
handling operations. The sensor 28 images the containers 14 after
they have been filled and have exited the carrier 12 so that
subsequent filling times can be adjusted based on the sensed liquid
levels. The filling time instructions or recipe for each different
filling valve will likely be unique. An additional sensor or camera
30 can also be provided along the input path 18 to observe the
containers 14 before being filled with liquid.
[0042] The sensor 28 is operative to correlate an individual
container 14 on the output conveyor 26 or the exit feed path B to
the valve 20 that provided fluid to that particular container 14.
The container 14 can be correlated to its particular filling valve
20 in any known manner. For example, indexing signals may be used
with an encoder or the sensor to allow the system to correlate each
inspection to the respective filling valve. Also, since the filling
valves 20 are assigned a number, as each container 14 passes the
sensor 28, its valve number is placed into memory along with the
level of liquid in the sensed container 14. Therefore, as each
container 14 is imaged by the sensor 28, the valve number is
extracted from memory and associated with the liquid level and any
other sensory information that has been logged. The vision system
including the sensor 28 functions to observe the containers 14 and,
thus, learn the performance of each individual valve 20 so as to
update the filling recipe periodically.
[0043] The sensor 28, shown in FIG. 1, is disposed just outside the
carrier 12, after an exit point 29, but may be placed at any point
after which filling is complete. A location may be chosen which
minimizes the effects of vibration, turbulence, centrifugal forces,
and other forces that may act on the liquid level in the bottle. By
having the sensor 28 focused on the fill area of a single bottle it
is possible to obtain high levels of resolution combined with a
refined illumination to produce a high quality image, such that the
system can employ sophisticated algorithms for monitoring each
valve's 20 performance.
[0044] FIG. 3 is a schematic diagram of a system consistent with
the present invention that incorporates the sensor 28 and a
container 14 positioned adjacent thereto. The image of the
container 14 acquired by the sensor 28 is stored in a memory of a
computer or processor 34 that performs functions, such as internal
data calculations and determining a volume of the fluid in the
containers 14. The sensor 28 has a field of view which includes a
surface 36 of the container's liquid 35 plus a buffer both above
and below the nominal fill level which is large enough to account
for the variation in fill level that the system may tolerate.
Accordingly, the sensor 28 is operative to detect an amount of
fluid 35 in the container 14 by detecting the fluid's level 36 and
sending the image information via an input signal line 37, in the
form of electronic data, to the processor or computer 34 for
storage and analysis. The analysis determines the liquid fill level
36 and determines if it is in a normal range of variation that is
acceptable. The processor 34 evaluates the sensed level in light of
previous readings and mathematically determines the mean and
standard deviation of such readings. The processor 34 also
calculates the confidence level and an appropriate statistically
significant sample size that is needed to provide a sufficient
number of liquid level 36 readings, before making a change to the
timing recipe for the particular valve 20 corresponding to the
sampled readings. Thereafter, the processor 34 provides an output
signal along data line 38 to a PLC 40 that compiles a calculated
time adjustment 41 for the valve 20. As shown, three valves 20, 20'
and 20'' are illustrated for the purpose of this description.
However, a typical filling machine would include many more valves.
In an exemplary embodiment, the PLC 40 then sends an "on" or "off"
electric signal 43, 43' and 43'' to air solenoid valve 42, 42' and
42'', which are respectively plumbed to the filling valves 20, 20'
and 20'' responsible for filling the sensed container 14, 14' and
14'' to send compressed air into the appropriate valves 20, 20' and
20'' via the input lines 25, 25' and 25'' to fill subsequent
containers with an updated time recipe 41 corresponding to the
particular valves 20, 20' and 20''. Depending on the processor's 34
configuration, it may include a display for graphically
illustrating the obtained data and for adjusting fill level
settings graphically. It will also be appreciated that the
processor 34 and the PLC 40 could be incorporated into one device
which performs the desired procedure.
[0045] By repeatedly measuring the fluid levels 36 of the
containers 14, 14' and 14'' that are sequentially filled by the
same valve, the historic attributes of the valves 20, 20' and 20''
can be obtained to provide trend data. For example, it can be
observed whether a particular valve stays open too long or not long
enough. It can also observe the repeatability of each valve by way
of the resultant filling consistency and standard deviation from
the mean. It can then be determined whether a flow adjustment needs
to be made in the high flow section 23 or the low flow section
24.
[0046] Based on the measured results of the liquid levels 36, the
processor 34 and the PLC 40 can provide an instruction to adjust
the elapsed time that the valves 20 remain open during the filling
procedure. The processor 34 maintains the historical database of
liquid levels 36 corresponding to the performance of each valve 20,
20' and 20''. Because the present elapsed filling times are known,
in addition to the liquid levels produced by the present filling
times, the system can make accurate recommendations to change the
elapsed times that the valves 20, 20' and 20'' remain open, so as
to continuously improve the accuracy of the filling procedure. For
example, if a particular valve is shown to be over filling or under
filling based on mathematical statistics including, for example,
mean and standard deviation calculations, for a certain sampling of
containers 14, 14' and 14'', the valve opening time may be
appropriately shortened or lengthened depending on the desired
corrections. An exemplary sampling amount may include between 40-60
containers 14, 14' and 14'' that are filled by the same valve, and
the amount of valve timing change may be a factor of
milliseconds.
[0047] The sensing or imaging of the liquid level may be
implemented with a range of technologies, including non-contact
technologies, for example, but not limited to, radio frequency
sensors, ultrasonic sensors, electro optical sensors, x-ray
sensors, laser scanners, infra-red sensors, capacitive sensors and
the like. The particular application, types of material out of
which the container 14 is manufactured, and the cost practicality
of the implementation may dictate which one is most applicable for
a particular filling application.
[0048] In an exemplary embodiment, the imaging system including the
camera or sensor 28 could utilize a machine vision configuration
with a strobed backlighting source. The camera 28 would snap an
image when a part detection sensor indicates the presence of the
filled container 14 at a particular position appropriate for
inspection. An encoder or resolver, operative from an area near the
conveyor 26 or exit feed path B, could then indicate the progress
of the container 14 until it is in an appropriate position for
imaging. At that point, an electronic subsystem or computer 34
would prepare the camera 28 to capture the image, while a strobed
backlighting is triggered to provide an illumination pulse which
freezes the movement of the container 14 for an instant while the
image is taken. An alternative to the strobing of the backlight is
to use a continuously "on" light source and electronically shutter
the camera at a high speed to provide a near equivalent image
capture scheme. It is also possible to use a technique called
smeared imaging which can have certain advantages as well as
drawbacks. With this technique, the camera shutter is purposely
held open when the container is in the field of view. The resultant
image is a smear of the vertical contrast as integrated over the
time that the container is traveling horizontally through the
image. If the smear window is chosen carefully, for some
applications, this provides a sort of averaging that may be
advantageous in reducing the amount of image processing
requirement. The challenge with this technique is that contrast may
be too suppressed for robustness in the inspection.
[0049] A backlit image may also be used which provides a
combination image that is part silhouette and partly a "light
transmission image" in which the liquid absorbs more light than the
unfilled top portion of the container 14. The "fill line" is then
clearly visible and is further amplified and more visible because
of the refraction of the light caused by the meniscus at the
interface of the liquid with the glass with the air space above
it.
[0050] The captured image is read out of the camera 28 and
transmitted into image processor electronics of the computer 34.
The image is then analyzed using algorithms, which may be
particularly designed into the software of the computer 34, for the
purpose of determining the fill level 36 from the image data. For
example, the image processing algorithm in the computer can compare
the contrast as vertical lines that are traced from the region of
the image that should definitely be liquid 35 up through the
transitional zone where the liquid interfaces with the air and then
into the air space. By doing this in the desired number of
locations in the measurement region, it is reasonable to determine
a numerical average that is representative of the liquid level 36.
Upon determination of the fill level 36, further algorithms are
used that are designed to analyze how the currently measured fill
level 36 compares to fill levels 36 of containers 14 that have been
measured previously to provide historical data and to derive
various aspects of trending data. The trending data can be used to
predict maintenance schedules and impending failure modes. For
example, the system may be able to ascertain that a particular
valve 20 is performing in an increasingly erratic way. This may
indicate a sticking solenoid or valve poppet. The historical data
is then used to update the respective filling valve actuation times
to obtain optimum filling results.
[0051] Additional aspects can be implemented to improve the
accuracy of fluid level readings under differing conditions. For
example, it is possible to use different wavelengths of light,
whether in the visible or the non-visible portions of the spectrum,
to provide a better contrast and, therefore, better measurements.
U.S. Pat. No. 5,365,084 teaches the advantages of wavelength
specific illumination systems that can use different combinations
and permutations of wavelengths from differing angles to highlight
and increase contrast as desired, the disclosure of which is hereby
incorporated, in its entirety, by reference. It may be advantageous
under some applications to use a wavelength specific illumination
system to help improve the measurements that are pertinent to
proper filling valve optimization. For example, some darker colored
bottles, like amber, may be difficult to illuminate with normal
visible backlight sources, but are readily penetrated with near
infrared illumination. At the same time, a green bottle is
penetrated nearly as well as an amber bottle and its grey scale
image does not show a substantially higher contrast than the amber
bottle. By using a combination of light wavelengths, it is possible
to not only better detect the correct fill level, but also to
detect if an incorrect color bottle has been filled.
[0052] It is also possible to use a similar technique with chosen
wavelengths to analyze foam differently than a dense liquid
product. For example, it may be determined empirically that 25 mm
of dense foam equals 10 mm of liquid, while 25 mm of low density
foam may only be the equivalent 4 mm of the same liquid. Such a
correlation may be made by reference to a look-up table.
[0053] The filling time periods for each valve may be even further
optimized beyond an initial timing determination. For example, the
additional camera or input sensor 30, shown in FIG. 1, can also
detect a container that is larger or smaller in volume than a
nominal specification, such that the actuation time of the
corresponding valve 20 can be adjusted proactively to obtain a
correct fill amount. As will be appreciated, it sometimes may be
appropriate to fill the containers by delivering a predetermined
volumetric amount or it may be appropriate to fill to a measured
fill line. The actual dimensions of the container 14 can directly
affect both of these approaches. Therefore, the use of the input
sensor 30 for inspecting incoming containers can be useful in
either situation. These and other features herein described can
contribute to an implementation of an adaptive, self learning, and
"smart" filling machine.
[0054] In further accordance with an exemplary embodiment of the
present invention, information sensed by the additional sensor
pertaining to container type, size, model, design, or style can be
used to trigger access to a database that has historical setting
filling recipes for each respective valve 20 for filling that
specific container. Such a pre-filling, or ingoing sensory system,
using the input sensor 30 can be useful in setting up the system
automatically, with little or no human operator attention.
[0055] The input sensor 30 may also be operative to identify
incorrect containers so that a particular valve in the filling
system is held closed and the incorrect container is not filled at
all, or so that it is rejected after filling. Thus, an incorrect
container, whether filled or empty, can be subsequently rejected
from the stream of containers as a proactive measure.
[0056] The processor 34 may include a programmable logic controller
(PLC) or they may be separate devices, as shown in FIG. 3, with
each having a central processing unit (CPU) and an input/output
interface. In the exemplary embodiment of FIG. 3, the processor 34
calculates and controls the timing recipes and sends them to the
PLC 40 via communications link for storage and execution. The
input/output interfaces facilitate communications between the
processor 34, the sensors (i.e., input), the PLC 40 and the valves
20 (i.e., outputs).
[0057] In operation, the processor 34 reads input data from the
sensor 28 and then "executes" or performs a control program using
the algorithms for optimizing the valves' 20, 20' and 20'' timing.
Based on the algorithms, the PLC 40 updates the elapsed time
instructions for the valves 20, 20' and 20'' via the output
interfaces.
[0058] As an alternative to using a PLC 40 for the valve firing,
electronic boards 39, 39' and 39'' connected to the data line 38
can be dedicated to a number of valves 20, 20' and 20'', as shown
in FIG. 4. The shown configuration includes one electronic board
per valve, but multiple valves could be controlled by a single
electronic board. Each such electronic board 39. 39' and 39'' would
be responsible for executing the timed on and off sequence for both
slow and fast coils of the valves 20, 20' and 20'' and would
perform this repetitive duty for each of the valves 20, 20' and
20'' that it is dedicated to controlling. The valves 20, 20' and
20'' could receive a trigger signal from a photocell or other
similar devices known in the art indicating when each filling valve
20, 20' and 20'' has passed a certain point in the rotation of the
carrousel 12. The electronic boards 39, 39' and 39'' would then
fire or execute a time recipe, to the respective valves 20, 20' and
20'', which is held in its non-volatile memory. Periodically, as
needed, each such electronic board 39, 39' and 39'' could send new
triggering recipes for each of its valves 20, 20' and 20'' based on
the fill level sensing measurements. Such dedicated electronic
boards 39, 39' and 39'' would typically be capable of accurately
and repeatedly executing a precise firing timing that would
facilitate optimization of the filling. FIG. 5 represents an
exemplary embodiment using the PLC 40 and the electronic board 39
together. The PLC 40 and electronic board 39 act together to
provide a signal for controlling the valve 20. For the sake of
simplicity, only one electronic board 39 is shown. However, in use,
multiple electronic boards 39 could be used to control multiple
valves 20.
[0059] In general, it may not be necessary to communicate to each
valve 20 for each individual filling procedure because the control
electronics of the valves 20 should accurately provide repeatable
elapsed times for the respective valves 20. The system will
periodically update the elapsed times as needed to maintain
accurate fluid levels though multiple fillings over a period of
time. As will be appreciated, there are variances in the
responsiveness and performance between different valves 20.
However, the most frequently changing component of the valve's 20
variable attributes may be the elapsed filling times, which are
sampled and analyzed to optimize fill levels.
[0060] A situation that should be avoided when sampling and
adjusting the valves 20 is known as valve setting "hunting".
"Hunting or oscillation" phenomenon is understood in many fields,
such as classical PID (Proportional-Integral-Derivative Control)
theory and/or mathematical statistical sampling theory. It is a
circumstance whereby an adjustment is made, which is not correct,
followed by a further adjustment, which is also not correct. In
effect, the system goes into a loop of corrections, never finding a
stabilized adjustment. By way of example, suppose an adjustment
appears to be required to the valve "on-time," based on previously
gathered measurements, but the timing adjustment recommended by the
system is based on one or more inaccurate measurements. Because the
recommended change is based on inaccurate measurements, the change
is based on the wrong input. The valve, however, faithfully
executes its filling time with the new lengthened or shortened
setting. Subsequently, as new measurements of the fill level are
made, it is again recognized that the fill level has been
improperly adjusted. A new adjustment is then required which may
also be based on an inaccurate measurement and may similarly assign
an improper value. As this type of flawed adjusting continues, it
is possible to create a continual "hunting" or oscillation
situation which does not promote optimized valve settings for the
filling machine. Therefore, a statistically significant change
should be reliably detected by way of the chosen statistically
significant sample size before a change in the valve triggering
timing is warranted. Thus, although it is possible to practice this
invention using single measurements of the fill level, it is not
recommended for most optimized results.
[0061] FIG. 6 is a perspective view of the sensor 28 positioned
approximate to the containers 14 so as to analyze the fluid level
of multiple containers 14 at one time. The operation of the sensor
28 and computer 34 in this embodiment is similar to that of FIGS.
3-5, except for data of multiple containers is obtained at one
time. It will be appreciated that the embodiments of FIGS. 3-5 may
similarly sense multiple containers simultaneously. The sensor 28
can work in conjunction with a backlight 44, which may be strobed
and extends the length of an area encompassing the sensed
containers 14. The data obtained by the sensor 28 is then
transferred to the computer 34 for analysis and, in a manner
similar to that described above, the derived information is
manipulated to provide fill time instructions to the respective
filling valves 20.
[0062] In a further embodiment, dimensional measurements of the
containers 14 are obtained by the additional sensor or camera 30,
shown in FIG. 1, prior to the filling operation. From the measured
dimensions, the volumetric capacity of individual containers 14
could be calculated by the computer 34 where further intelligence
is applied to modulate the filling recipes accordingly. The
volumetric calculation can be used to point to a particular filling
recipe, from a selection included in a look-up table, provided in
the valve's electronics or the computer 34, for example. This
process can be more efficient than transmitting a completely new
filling recipe for each bottle and could result in more precise
filling levels for certain types of bottles. For example, it is
known that certain types of bottles have a much greater level of
manufacturing variation than other types, such that this additional
feature could be useful to extend the basic functionality of the
smart, vision-based filling system.
[0063] It is contemplated that there are many other aspects that
the system can learn and incorporate in the performance history for
each valve besides the filling times. Accordingly, to affect a
reliable and consistent filling in an exemplary embodiment of the
invention, it is beneficial that other parameters of the filling
machine, besides the filling times, be held to tightly controlled
levels. For example, the pressure of the filling liquid should be
consistent so that it does not create another variable that affects
the system.
[0064] Therefore, additional aspects of learning and acquiring
feedback may be utilized. A number of data aspects could be used to
more precisely characterize each valve's performance over time. In
an exemplary embodiment, the computer 34 could become a central
repository for sensory data input which would relate to overall
filling performance. For example, additional data such as
temperature, pressure, valve current signature, flow rates at other
points in the machine, and many other pieces of data could be
incorporated into the historical performance chart. One could,
therefore, use this information to mathematically project
performance in the future and could incorporate the information
into a learning neural network which would predict performance,
enhance filling repeatability, and predict machine maintenance as
well.
[0065] Contact sensing technology may be used which weighs the
filled container 14 to provide historical data. For example, the
weight of a currently measured filled container 14 could be
compared with past measurements to provide historical data used to
evaluate and determine optimum filling valve actuation durations
and settings.
[0066] Moreover, the containers 14 may be sensed from multiple
different directions and angles to get different views. This
sensing may apply to the "pre-look" (unfilled container) which is
carried out by the camera or sensor 30 as well as the "post-look"
(filled container) which may be carried out by the camera or sensor
28. This feature is useful for prospectively determining the exact
size (volume) of each bottle that will be or has been filled.
Various types of sensor technologies could be used for performing
this procedure such as, for example, the mass sensing technology
described in U.S. Pat. No. 6,872,895, which is hereby incorporated
in its entirety by reference.
[0067] FIG. 7 represents a flow chart of an exemplary method of the
invention. The process begins with transporting the containers 14
by the carrier 12 (S100). The liquid is then dispensed into the
containers 14 through the filling valve 20 (S110), such that the
flow is controlled by manipulating the precise amount of time that
each filling valve 20 remains open (S120). The containers 14 are
then conveyed along the exit feed path B after they have exited the
carrier 12 (S130), such that the level 36 of liquid in the
containers 14 is detected to produce a signal (S140). After the
level of liquid 36 is sensed, data is gathered and, when needed, a
period of time that the valve remains open for subsequent fillings
is adjusted (S150).
[0068] The flow of liquid into a plurality of the containers 14 is
controlled using separate filling valves 20, such that data is
collected to represent the level of liquid 36 provided by the
separate valves 20. Based on the data, the period of time that each
of the separate valves 20 remains open for subsequent fillings can
be adjusted. It will be appreciated that the levels of liquid in a
single container or, more preferably, but not necessarily, multiple
containers, may be detected before making an adjustment, even when
the levels of liquid are not consistent between the multiple
containers, as long as the detected levels are within an acceptable
range. By providing the entrance feed path 18 to the carrier 12,
the containers 14 can be preliminarily observed by the input sensor
30 to determine the volumetric capacity of the containers before
the containers are disposed on the carrier.
[0069] FIG. 8 represents a method according to a further exemplary
embodiment that incorporates pre-fill sensing, using the camera or
sensor 30 shown in FIG. 1, for example. Operations of FIG. 8 are
similar to those in of FIG. 7, while further including an operation
which detects physical attributes and/or specifications of the
containers using a pre-fill sensor or camera (S102). After the
containers are viewed by the pre-fill sensor or camera, access is
made to a database to obtain stored filling recipe information
corresponding to the detected container (S104). Therefore,
predetermined elapsed times for the valves 20 can be initially
used, which may then be adjusted based on the data gathered by the
sensor 28, and/or sensor 30, or provided by other sensory
inputs.
[0070] The method also contemplates utilizing all other additional
aspects of the invention discussed above, including the aspects of
learning and acquiring feedback. For example, the method may
include using a number of data aspects to more precisely
characterize each valve's performance over time and use the
computer 34 as the central repository for sensory data input that
would relate to overall filling performance.
[0071] Inaccuracy in the sensing or measuring of the liquid may be
inevitable because of waves, ripples, turbulence, foam, bubbles,
sloshing and other disturbances that occur at the liquid to air
interface at the top of the liquid, which has just been filled,
into the container 14. To improve such disturbances, a length of
the output conveyor 26 may be provided to allow for some settling
time before the liquid is measured by the sensor 28.
[0072] Another contributor to inaccurate measurements of a fill
level includes a range of normal process variations in the
containers 14 themselves. For example, the container 14 can have
bubbles or blisters in a sidewall through which the sensor 26 must
view. Because of the nature of glass or plastic containers, this
causes an anomalous refraction or reflection that can change the
image from which the measurement is made. Many other similarly
detrimental anomalies, such as ridges or partially choked necks can
cause inaccurate measurements. Therefore, the various types of
sensors and cameras described above, along with an appropriate
sampling amount, should be taken into consideration based on the
particular filling application.
[0073] The previous description of the exemplary embodiments is
provided to enable a person skilled in the art to make and use the
present invention. Moreover, various modifications to these
embodiments will be readily apparent to those skilled in the art,
and the generic principles and specific examples defined herein may
be applied to other embodiments without the use of inventive
faculty. Therefore, the present invention is not intended to be
limited to the embodiments described herein, but is to be accorded
the widest scope as defined by the limitations of the claims and
equivalents thereof.
* * * * *