U.S. patent application number 09/824445 was filed with the patent office on 2002-04-18 for method and apparatus for monitoring parameters corresponding to operation of an electrophotographic marking machine.
Invention is credited to Eck, Edward M., Hockey, David, Regelsberger, Matthias H., Stern, Philip.
Application Number | 20020044783 09/824445 |
Document ID | / |
Family ID | 24288203 |
Filed Date | 2002-04-18 |
United States Patent
Application |
20020044783 |
Kind Code |
A1 |
Eck, Edward M. ; et
al. |
April 18, 2002 |
Method and apparatus for monitoring parameters corresponding to
operation of an electrophotographic marking machine
Abstract
An electrophotographic marking machine is described including a
first set of data with a plurality of parameters corresponding to a
plurality of prior electrophotographic markings or frames. The
electrophotographic marking machine further includes a second set
of data selected from the first set of data based upon a
predetermined set of criteria. In addition, the electrophotographic
marking machine has a volatile storage device for storing the first
set of data, and a non-volatile storage device for storing the
second set of data. A method for assessing operability of an
electrophotographic marking machine is also described. The method
includes the steps of recording a first set of data including a
plurality of parameters corresponding to a plurality of prior
electrophotographic markings, storing the first set of data in a
volatile storage device, selecting a second set of data from the
first set of data based upon a predetermined set of criteria, and
storing the second set of data in a non-volatile storage
device.
Inventors: |
Eck, Edward M.; (Lima,
NY) ; Regelsberger, Matthias H.; (Rochester, NY)
; Stern, Philip; (Spencerport, NY) ; Hockey,
David; (Brockport, NY) |
Correspondence
Address: |
Matthew J. Sampson
McDonnell Boehnen Hulbert & Berghoff
32nd Floor
300 S. Wacker Drive
Chicago
IL
60606
US
|
Family ID: |
24288203 |
Appl. No.: |
09/824445 |
Filed: |
April 2, 2001 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09824445 |
Apr 2, 2001 |
|
|
|
09572524 |
May 17, 2000 |
|
|
|
Current U.S.
Class: |
399/10 |
Current CPC
Class: |
G03G 15/5079 20130101;
Y02P 90/14 20151101; Y02P 90/02 20151101; G03G 2215/00118 20130101;
G03G 15/553 20130101; G03G 15/55 20130101; G03G 2215/00109
20130101 |
Class at
Publication: |
399/10 |
International
Class: |
G03G 015/00 |
Claims
What is claimed is:
1. An electrophotographic marking machine comprising: a first set
of data including a plurality of parameters corresponding to a
plurality of prior electrophotographic markings; a second set of
data selected from the first set of data based upon a predetermined
set of criteria; a volatile storage device for storing the first
set of data; and a non-volatile storage device for storing the
second set of data.
2. The electrophotographic marking machine of claim 1 wherein the
volatile storage device is a memory buffer that is maintained on a
first in, first out basis.
3. The electrophotographic marking machine of claim 1 wherein the
non-volatile storage device is a hard disk.
4. The electrophotographic marking machine of claim 1 wherein the
volatile storage device is a memory buffer that is maintained on a
first in, first out basis, and the non-volatile storage device is a
hard disk.
5. The electrophotographic marking machine of claim 1 wherein the
predetermined set of criteria includes at least one error code.
6. The electrophotographic marking machine of claim 1 wherein the
first set of data includes parameters corresponding to a
predetermined number of electrophotographic markings.
7. An electrophotographic marking machine for producing a plurality
of frames comprising: a first set of data including a plurality of
parameters corresponding to the plurality of frames; a second set
of data selected from the first set of data based upon a
predetermined set of criteria; a volatile storage device for
storing the first set of data; and a non-volatile storage device
for storing the second set of data.
8. The electrophotographic marking machine of claim 7 wherein the
plurality of frames are sequential.
9. The electrophotographic marking machine of claim 7 wherein the
volatile storage device is a memory buffer that is maintained on a
first in, first out basis.
10. The electrophotographic marking machine of claim 7 wherein the
non-volatile storage device is a hard disk.
11. The electrophotographic marking machine of claim 7 wherein the
volatile storage device is a memory buffer that is maintained on a
first in, first out basis, and the non-volatile storage device is a
hard disk.
12. The electrophotographic marking machine of claim 7 wherein the
predetermined set of criteria includes at least one error code.
13. A method for assessing operability of an electrophotographic
marking machine, the method comprising the steps of: recording a
first set of data including a plurality of parameters corresponding
to a plurality of prior electrophotographic markings; storing the
first set of data in a volatile storage device; selecting a second
set of data from the first set of data based upon a predetermined
set of criteria; and storing the second set of data in a
non-volatile storage device.
14. The method of claim 13 further comprising the step of using a
memory buffer that is maintained on a first in, first out basis for
the volatile storage device.
15. The method of claim 13 further comprising the step of using a
hard disk for the non-volatile storage device.
16. The method of claim 13 further comprising the steps of using a
memory buffer that is maintained on a first in, first out basis for
the volatile storage device, and using a hard disk for the
non-volatile storage device.
17. The method of claim 13 further comprising the step of using at
least one error code for the predetermined set of criteria.
18. The method of claim 13 further comprising the step of using
parameters corresponding to a predetermined number of
electrophotographic markings for the first set of data.
19. The method of claim 13 further comprising the step of using the
predetermined set of criteria associated with the second set of
data to identify the second set of data on the non-volatile storage
device.
20. The method of claim 13 further comprising the steps of using at
least one error code for the predetermined set of criteria,
associating the at least one error code with the second set of
data, and using the at least one error code associated with the
second set of data to identify the second set of data on the
non-volatile storage device.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This is a continuation-in-part application of U.S. patent
application Ser. No. 09/572,524, entitled "Method and Apparatus For
Monitoring Parameters Corresponding To Operation Of An
Electrophotographic Marking Machine," and filed on May 17,
2000.
FIELD OF INVENTION
[0002] This invention relates to electrophotographic marking
machines, and more specifically to an apparatus and method for
monitoring and storing operating parameters of the marking
machine.
BACKGROUND OF THE INVENTION
[0003] In servicing and repairing electrophotographic (EP) marking
machines, it has long been observed that the accurate analysis of
the root cause of a functional failure or malfunction is critical
in the successful implementation of the proper repair. Accurate and
quick error analysis reduces the costs for troubleshooting itself
as well as the costs for replacement parts. Any tools suited to the
effective and accurate troubleshooting of malfunctions will
ultimately yield higher customer satisfaction.
[0004] In addition, most consumables and components are replaced in
accordance with manufacturer's recommendation which is based on
copy or page-count. The end-of-life for the component or consumable
is thus inferred rather than measured. As the copy count does not
accurately reflect power-up and power-downs of the machine as well
as ambient operating conditions, maintenance based on copy or page
counts is inherently unreliable.
[0005] Therefore, a need exists for monitoring the operating
conditions of an EP marking machine, wherein the operating
parameters correspond to actual usage of the machine. A need also
exists for permitting error analysis and trend analysis, and for
recording information corresponding to such analyses in order to
enable a field/service engineer to troubleshoot/repair the EP
marking machine. Similarly, a need exists to be able to store
error/failure information in at least volatile memory, as well as
to be able to store certain critical error/failure information in
permanent (i.e., non-volatile) storage, such as a hard disk.
SUMMARY OF THE INVENTION
[0006] The present application provides an electrophotographic
marking machine comprising a first set of data including a
plurality of parameters corresponding to a plurality of prior
electrophotographic markings or frames. The electrophotographic
marking machine of the present invention further comprises a second
set of data selected from the first set of data based upon a
predetermined set of criteria. In addition, the electrophotographic
marking machine of the present invention comprises a volatile
storage device for storing the first set of data, and a
non-volatile storage device for storing the second set of data.
[0007] The present application provides a method for assessing
operability of an electrophotographic marking machine. The method
of the present invention comprises the steps of recording a first
set of data including a plurality of parameters corresponding to a
plurality of prior electrophotographic markings, and storing the
first set of data in a volatile storage device. The method of the
present invention further comprises the steps of selecting a second
set of data from the first set of data based upon a predetermined
set of criteria, and storing the second set of data in a
non-volatile storage device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic representation of a diagnostic system
for an EP marking machine.
[0009] FIG. 2 is a schematic representation of an alternative
configuration of a diagnostic system for an electrophotographic
marking machine.
[0010] FIG. 3 is a schematic representation of a further
configuration of a diagnostic system for an electrophotographic
marking machine.
[0011] FIG. 4 is a graph of representative data.
[0012] FIG. 5 is a graph of alternative representative data.
[0013] FIG. 6 is a graph of further representative data.
[0014] FIG. 7 is a schematic representation of a further diagnostic
system for an EP marking machine.
[0015] FIG. 8 is a flow diagram illustrating a method for
monitoring operation parameters of an EP marking machine with the
diagnostic system of FIG. 7.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0016] Referring to FIG. 1, the present invention includes a
diagnostic system 20 for assessing operability of a machine 22. It
should be understood that the diagnostic system 20, as well as the
machine 22, may have more or fewer components than shown in FIG. 1,
depending on manufacturing and/or consumer preferences.
[0017] The diagnostic system 20 includes a plurality of
high-frequency inputs 26 and a plurality of low-frequency inputs 24
from the machine 22, and a process recorder 30 connected to the
inputs 24 and 26. The inputs or signals corresponding to the inputs
are retained in electronic files 32 and 34, containing respectively
data sets of high-frequency data 36 and low-frequency data 38. Each
of the data sets 36 and 38 contains a respective plurality of
subsets 40 and 42, and each subset has a series of consecutive data
points from a different input. FIG. 1 shows, by way of example, two
each of the high and low-frequency inputs 26 and 24, and also one
shared input 28 which provides data for both the high-frequency and
low-frequency data sets 36 and 38. In practice, the total number of
inputs may typically be ten or more, and several may be shared
inputs such as 28. However, it is not precluded that each and every
input will provide data for only one of the data sets 36 or 38.
[0018] The recorder 30 is a storage device for retaining the data
sets 36 and 38. Preferably, the recorder 30 is a memory that
retains the data sets independent to the powered status of the
machine 22. The recorder 30 is selectively or permanently connected
with a computer 44 having a keyboard 46 and a display 48. On
provision of an appropriate command from the keyboard 46, the files
32 and 34 can be downloaded into the computer 44, and selected data
retrieved therefrom. The selected data can be displayed as a
graphic image 50 on the screen 48. Optionally, the computer 44 can
be connected with a printer 52, and the image 50 can be printed out
as a hard copy 54.
[0019] In a preferred embodiment of the invention, shown
schematically in FIG. 2, the machine 22 is an EP marking machine or
engine 60, such as a copier or printer. The EP machine includes the
recorder 30. The EP machine 60 has a keypad 62 for entering
commands, a screen 64 for prompting and displaying commands. A
platen 66 for receiving an original document to be copied, and a
tray 68 which can receive frames 70 printed by the copier 60.
Neither an original for copying, which is placed on the platen 66,
nor a platen cover are represented in the drawings. Also omitted
from the drawings is any representation of an automatic feeder with
which EP machines are commonly equipped. The computer 44 is any of
a variety of computing devices including, but not limited to,
dedicated servicing devices as well as laptop computers. The
computer 44 and the EP machine 60 are configured to provide
operable interconnection during a service call, so that the
computer operably connects to the recorder 30. The operator can
download the files 32 and 34 into the computer 44 and display
selected data on the screen 48 as a graphic image 50. Optionally,
the computer 44 is connected to a printer 52 to generate a hard
copy 54 of the data. Alternatively, for the purpose of generating a
hard copy, the computer 44 may be connected to the data input of
the EP machine 60 to produce said hardcopy. It is understood that
the graphical display and hard copy generation can be done during
the service call or at a later time.
[0020] In another embodiment of the invention, shown schematically
in FIG. 3, the EP machine 60 would host the recorder 30, while the
keypad 62 and the screen 64 would not only serve to provide for the
day-to-day operation of the EP machine, but would also be
interactively connected with the recorder 30. The relationship
between screen 62, the keypad 64 and the recorder 30 would be
identical to that between the computer keyboard 46, the computer
screen 48 and the recorder 30 in the preferred embodiment. This
embodiment would be particularly convenient for a trained operator
who would normally be stationed at the copier site.
[0021] The term EP History corresponds to the high frequency data
set 36 and the term EP Trend corresponds to the low-frequency data
set 38. A record of EP History (i.e., operation parameters) is
useful for diagnosing the causes of actual malfunctions. For every
printed marking or frame, key EP-parameters are recorded
characterizing the operation of all image-forming subsystems. The
high-frequency data set 36 includes all selected operation
parameters for 1000 frames, i.e., the data recording is structured
such that all selected operation parameters of the last 1000 frames
are always available upon request. Should the printer stop with,
e.g., a fatal error, the field/service engineer is able to access
the last 1000 prints. Typical EP History includes values
corresponding to such operation parameters as print counter,
primary charger voltage, primary power supply setpoints,
electrometer readback, densitometer output, transfer setpoint, film
strain gauges, film voltage before exposure, film voltage after
exposure, toner concentration, toner monitor, fuser thermistor,
toning level sensor, toning bias, replenisher rate, fuser
temperature, and process errors.
[0022] The EP Trend data provides a tool for analyzing the
long-term drift of the operating conditions of the machine 22. The
parameters of the low frequency (EP trend) data set may include
values corresponding to print counter, date and time, film voltage
before exposure, film voltage after exposure, toner concentration,
toner concentration setpoint, developer life counter. Typically,
the machine 22 includes software for setup or power up of the
machine. The setup software applies each time the machine 22 is
powered up. In addition, as many machines will run continuously
(but for maintenance) the software includes an automatic, timed,
execution. The powered up setup and the automatic initiated setup
are termed "autosetups." With every completed autosetup, the
achieved operating conditions are recorded in the low frequency
data set as the EP trend data. Each occurrence of the autosetup
results in the recording of key EP parameters. The EP parameters
include the operating setpoints of the image-forming subsystems.
Although the long term, EP trend data (low-frequency data set 38)
includes all selected data for 500 autosetups, it is understood
that the long term data set may include a fewer or greater number
of points. The particular number of autosetups recorded is at least
partially determined by the specific machine, the operating
conditions as well as desired performance parameters. Thus, in the
present example, the data recording is structured such that the
selected operating conditions of the last 500 autosetups are
maintained at the machine. Since the autosetup is initiated each
time the machine is powered up, and typically every 6 hours (of
continuous operation), approximately 200 workdays of trend data are
normally included in the low frequency data set.
[0023] The following examples will provide a better understanding
of the diagnostic system 20. However, assistance in trouble
shooting the machine 22 accurately and effectively is not limited
to the examples shown.
EXAMPLE 1
[0024] Error Analysis Using Data of the Short-Term Recorder
[0025] In an example depicted in FIGS. 4 and 5, the operator and
the service technician of the printer observed the loss of
developer at apparently random intervals. No cause or machine
malfunction could be identified at the time of trouble shooting.
Repeatedly, the developer was replaced. FIG. 4 shows a plot in
which the x-axis 80 represents the number of frames printed since
the last power-up, and the y-axis 82 represents any of a plurality
of EP process voltages and also transfer current, which are
parameters known in the art. In FIG. 5, the y-axis 82 represents EP
controls over the same sequence of prints as those of FIG. 4. In
particular, the recorded controls were charging efficiency,
densitometer efficiency and bias offset, which again are terms
known in the art. Analysis of the data revealed that the charger
efficiency suddenly dropped causing the offset voltage
V.sub.0-V.sub.bias to drop from the desired 110V to only 40V. The
incident is marked by arrows 84 in FIG. 4 (V.sub.0 and V.sub.0
average) and FIG. 5 (bias offset average). Similarly, the
efficiency of the charger suddenly increased, causing an increase
in the offset voltage from the desired 110V to about 170V. A
material defect in the high-voltage plastic components of the
charger was identified as the root-cause providing a low impedance
electrical path to ground triggered by environmental conditions.
The charger was replaced and the problems were resolved.
EXAMPLE 2
[0026] Trend Analysis Using Date of the Long-Term Recorder
[0027] As components and consumables age, the image-forming
subsystems degrade in their performance. Beyond certain limits, the
image quality will suffer. With the long-term recorder incorporated
into the marking engine controller (MEC), trends in operating
setpoints of the image-forming subsystems can be analyzed and
projections for end-of-life of consumables and/or components are
based on data. In FIG. 6, the x-axis 80 is marked by dates covering
about six weeks. Since each autosetup event is recorded in real
time, the successive events can be plotted with reference to the
x-axis 80, and trends observed. The example of FIG. 6 shows
setpoint data for the primary charging system, the bias voltage,
the voltage after exposure and the transfer current, which are
represented by the y-axis 82. All setpoints are increasing as it is
expected for new developer and a new photoconductor. With a very
low monthly volume of about 55K images, the peak in operating
points is not yet achieved. Towards the end-of-life of the
developer the charge-to-mass ratio of the developer will decrease
and with it the setpoints. At the manufacturer's recommended values
for the setpoints, the developer in terms of charge-to-mass ratio
is very likely the limiting factor in achieving the desired image
quality. The developer should then be changed.
[0028] Over time, the field engineer based on his own experience
and knowledge of the customer job stream will be able to assess
whether e.g. developer replacement should be performed while he is
at the site or deferred until his next visit. In addition, since
many EP process issues are charge-to-mass (Q/m) related, the field
engineer with his knowledge of the customer's jobstream can select
a particular customer target indicating a Q/m-related artifact. As
part of the field engineer's adaptive learning, the selected target
printed at regular intervals (e.g. every service call) in
conjunction with the recorded trend data will yield a customer
specific profile for end-of-life of consumables and components. A
customer specific profile for usage of consumables or components
can further be augmented and refined by employing the use of fuzzy
logic predictions rather than deterministic predictions of
conventional programming tools. The combination of data recorded by
the marking engine itself together with input by customer or field
engineer into the maintenance database stored on the machine will
after a learning period yield the customer profile.
[0029] The compositions of the high-frequency and low frequency
data sets, 36 and 38 respectively, are selected based on their role
in either short-term or long-term analysis. Each sample data set 36
and 38 is recorded at a different predetermined frequency. Some
data are recorded in common for both long-term and short-term
analysis, albeit at the different frequencies.
[0030] It is theoretically possible that the EP marking machine may
be operable for extended periods with only minimal operation. Such
an extreme but most unlikely circumstance could reverse the
magnitudes of the frequencies or data-gathering periods from those
which would normally be expected. It will therefore be understood
that in the foregoing specification, the usages "short-term",
"long-term", "high frequency" and "low-frequency" are chosen
because they overwhelmingly represent the normal manner of using
the machine.
[0031] Error Context Sensitive Data Logging
[0032] FIG. 7 shows a further embodiment of a diagnostic system 20a
for assessing operability of a machine 22. The diagnostic system
20a shown in FIG. 7 is identical to the diagnostic system 20 shown
in FIG. 1, except that the diagnostic system 20a further comprises
a pair of error tables 39, 39a that are integrated with, or at
least connected to and in communication with, the recorder 30, as
well as a non-volatile storage device 31 connected to and in
communication with the recorder 30. For ease of illustration, and
to avoid unnecessary repetition and redundancy, the diagnostic
system 20a will only be shown and described herein with reference
to a generic machine 22 that is separate from the recorder 30 and
the computer 44. It should be understood, however, that the machine
22 of the diagnostic system 20a may be an EP marking machine or
engine 60, such as a copier or printer, and that the recorder 30
and/or the computer 44 may be integrated into the EP marking engine
60 in the diagnostic system 20a (see FIGS. 2 and 3). In other
words, the previously described embodiments shown in FIGS. 2 and 3
may be modified to include the error tables 39, 39a and the
non-volatile storage device 31 of the diagnostic system 20a.
[0033] In the diagnostic system 20a, every error produced by and
associated with a printed marking or frame is assigned an error
code 41 (referenced in FIG. 7 as "EC"), which in turn is recorded
by and stored in an error logging table 39. The error logging table
39 is preferably integrated into the recorder 30, as stated above,
but may alternatively comprise a separate component of the
diagnostic system 20a. As shown in FIG. 7, the error logging table
39 is preferably connected to and in communication with the
electronic file 32 of the recorder 30 in order to obtain the error
codes produced by a printed marking or frame, and is also
preferably connected to and in communication with the non-volatile
storage device 31. In addition, the error logging table 39 is
further connected to and in communication with an active error
table 39a that contains a predetermined set of criteria, which is
preferably a list of one or more specific and predetermined error
codes 41a (referred to herein as "active error codes" and
referenced in FIG. 7 as "AEC"). As with the error logging table 39,
the active error table 39a is preferably integrated into the
recorder 30, but may alternatively comprise a separate component of
the diagnostic system 20a.
[0034] The active error codes may be set and configured by the user
and/or field/service engineer of the machine 22. As explained in
more detail below, the active error codes are used to trigger the
permanent storage of the high frequency data set 36 contained
within the electronic file 32 stored within the recorder 30, by
passing the high-frequency data set 36 to the non-volatile storage
device 31. Examples of such active error codes that may be used to
trigger the transfer of the high-frequency data 36 that is to be
stored in the non-volatile storage device 31 include V.sub.0 at
maximum, charging efficiency too low, densitometer reading to high,
electrometer reading less than 150V, V.sub.0 adjustment larger than
allowed, etc. It should be understood that there may be any number
of active error codes listed in the active error table 39a,
depending on service and/or user preferences.
[0035] In the diagnostic system 20a, when an error code 41 is
recorded by the error logging table 39 that matches one of the
active error codes 41a contained within the active error table 39a,
the entire contents of the electronic file 32 (i.e., the entire
high-frequency data set 36), together with the triggering error
code 41, is preferably passed from the recorder 30 into the
non-volatile storage device 31. The comparison between the error
codes of the error logging table and the active error codes of the
active error table is preferably integrated into the recorder 30,
but may also be performed by the processor and software of the
computer 44. Alternatively, additional hardware and/or software
(not shown) other than the computer's processor and software may be
used to for such a comparison.
[0036] The non-volatile storage device 31 is preferably connected
to and in communication with not only the recorder 30, but also the
electronic file 32 that contains the high-frequency data set 36, as
well as the error logging table 39. As a result of this
configuration, data from the high-frequency data set 36 and any
triggering error codes 41 may be passed along to the non-volatile
storage device 31 for more permanent storage. The non-volatile
storage device 31 is a permanent storage device because it is not
maintained on a first in, first out basis (FIFO), such as a hard
disk. In contrast, the recorder 30 of the diagnostic system 20a is
a volatile storage device, such as a memory buffer, that is
maintained on a FIFO basis. As a result, the data stored in the
recorder 30 continuously changes as new prints are run and new
parameters are transferred into the recorder 30, while the data
stored in the non-volatile storage device 31 is "permanently"
maintained until actively deleted by a user. In any event, both the
non-volatile storage device 31 and the volatile recorder 30
preferably retain their stored/recorded data at any given time
independent to the powered status of the machine 22.
[0037] As shown in FIG. 7, the non-volatile storage device 31
comprises one or more electronic files 33 that each contain a data
set 37 of high-frequency data (referred to herein as "error data")
from the electronic file 32 of the recorder 30, and the error code
41 that triggered the transferring and permanent storage of such
error data 37. Each error code 41 is preferably associated with its
electronic file 33 and its error data 37 in such a manner as to
allow a field/service engineer to easily search for and locate an
electronic file 33 and a set of error data 37 based on the
associated error code 41. The error data is preferably comprised of
all of the subsets 40 of the consecutive data points or parameters
stored in the recorder 30 that corresponding to each of a plurality
of printed markings or frames. For example, if data points or
parameters are recorded in the electronic file 32 of the recorder
30 for the last 1000 prints, the same data points or parameters for
those 1000 prints are transferred and stored in the non-volatile
storage device 31 when an active error code is triggered.
Alternatively, however, it is conceivable that fewer than all of
the data points or parameters (e.g., only the data points or
parameters for the last 500 prints, rather than all 1000 prints)
may be transferred to and stored by the non-volatile storage device
31, depending on service and/or user preferences.
[0038] As shown in FIG. 7, the non-volatile storage device 31 is
selectively or permanently connected with the computer 44. As with
the electronic files 32 and 34, any electronic file 33 may then be
downloaded into the computer 44, and selected error data 37
retrieved therefrom. The selected error data may be displayed as a
graphic image 50 (e.g., list, table, graph, etc.) on the screen 48.
Optionally, the computer 44 may be connected with a printer 52, and
the image 50 can be printed out as a hard copy 54. Alternatively,
for the purpose of generating a hard copy, the computer 44 may be
connected to the data input of the EP machine 60 to produce said
hardcopy.
[0039] The operation of the diagnostic system 20a, as well as a
method 100 for monitoring operation parameters of an EP marking
machine with the diagnostic system 20a, will now be described with
reference to FIG. 8. For ease of illustration purposes only, error
codes will be used in the method 100 for the predetermined criteria
that provides the basis for selecting the error data 37 of the
non-volatile storage device. It should be understood that the
predetermined criteria may be any number of different factors,
depending on operating and/or maintenance preferences. The method
100 begins with Step 101, wherein the operation parameters (or data
points) of the marking machine for each printed marking or frame
are sent to the recorder 30 and stored in a first data set (e.g.,
the high frequency data 36 of the electronic file 32). An error
code is then issued in Step 102, and the error code is recorded by
and stored in the error logging table in Step 103.
[0040] A determination is then made in Step 104 as to whether the
error code is listed in the predetermined criteria for the
non-volatile storage device 31. In the previously described
embodiment of the diagnostic system 20a, this step would involve
comparing the error code to the list of active error codes
contained within the active error table. If the error code is not
listed (e.g., the error code is not an active error code), then the
operation parameters corresponding to the error code are
temporarily stored on the recorder 30 in the first data set (Step
105), and the method 100 ends. On the other hand, if the error code
is listed in the predetermined criteria (e.g., the error code is an
active error code), then the issued error code and the entire
content of the first data set (e.g., the high frequency data 36 of
the electronic file 32) corresponding to the issued error code are
sent from the recorder to the non-volatile storage device in Step
106. The transferred content preferably comprises the entire
content of the first data set that existed (i.e., present in the
recorder 30) at the time the error code was issued. Thus, since the
content of the first data set is preferably always changing as new
operation parameters are added and old ones are deleted on a FIFO
basis, the content of the first data set that is transferred to the
non-volatile storage device may be referred to herein as a second
data set. As noted above, however, it should be understood that the
second data set may include less than the entire content of the
first data set at any given time.
[0041] In Step 107, the issued error code and the operation
parameters corresponding to the issued error code are permanently
stored as error data (e.g., error data 37) in an electronic file
(e.g., the electronic file 33) located on the non-volatile storage
device. Once stored in the electronic file on the non-volatile
storage device, the error data may be retrieved and accessed by an
operator and/or field/service engineer via a computer (e.g.,
computer 44) in Step 108. More specifically, the field/service
engineer may search for and retrieve the error data based on its
associated error code, which is preferably maintained in the
electronic file stored on the non-volatile storage device.
[0042] It should be understood that while the non-volatile storage
device 31 is shown as a separate component in FIG. 7, it may be
readily combined with the volatile storage device (i.e., recorder
30) to form an integral storage device with both volatile and
non-volatile recording capabilities. It should also be understood
that while data is described as being transferred from the recorder
30 to the non-volatile storage device 31 in the diagnostic system
20a, data may be sent directly to the non-volatile storage device
31 without passing through the recorder 30. For example, the
high-frequency inputs 26 (as well as any shared inputs 28) may be
connected to and run through the computer 44, before being
connected to both the recorder 30 and the non-volatile storage
device 31. In such an example, the computer 44 would include the
error logging table 39 and the active error table 39a for the
necessary comparison of error codes and triggering of permanent
data storage, and the data carried by the inputs 26, 28 may be
directed to either the recorder 30 or the non-volatile storage
device 31, or both, by the computer 44.
[0043] In addition, it should be understood that the active error
code trap and the non-volatile storage device may be disabled and
deactivated in the diagnostic system by the operator and/or
field/service engineer, if so desired. With the active error code
trap being disabled, the operation parameters are stored solely in
the volatile recorder 30.
[0044] While the present invention has been described in terms of
an EP marking machine, it is understood, the invention can be
employed with process lines and manufacturing. In particular, the
invention may be employed with coating processes, production or
creation of products.
[0045] According to the present invention, the error context
sensitive storage of EP-process data, such as operation parameters,
causes the marking engine (or other machine) to automatically
accumulate EP-process data leading to pre-selected errors and
failures. The field/service engineer can retrieve multiple
EP-process data sets from the permanent storage device and analyze
the data, e.g., with respect to similarities leading to the same
error and/or failure. Similarly, with multiple error and/or failure
codes initiating the error context sensitive data logging according
to the present invention, the field/service engineer is enabled to
trouble-shoot marking engine malfunctions without relying on the
operators description and/or the time consuming recreation of the
error and/or failure conditions.
[0046] The present invention has been described in connection with
certain embodiments, but it is not intended to limit the scope of
the invention to the particular forms set forth. On the contrary,
it is intended to cover such alternatives, modifications, and
equivalents as may be included within the spirit and scope of the
invention as defined by the appended claims.
* * * * *