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Description  |
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This invention relates to web processing apparatus and method. More particularly, it relates to a system of modular web
processing units which may be easily reconfigured to perform different overall web finishing functions of diverse types.
This application is a continuation in part of my earlier co-pending, commonly assigned U.S. application Ser. No. 695,963 filed Jan. 29, 1985 (now U.S. Pat. No. 4,648,540) which is, in turn, a continuation in part of my still earlier
co-pending commonly assigned U.S. application Ser. No. 675,149 filed Nov. 27, 1984 abandoned. The contents of both these earlier applications are hereby incorporated by reference.
Elongated webs of paper product are often used to produce finished paper business forms of various types. For example, checks, ledger sheets, statements of accounts, invoices, etc. often start out as large rolls of blank paper web. The web is
then processed in many different ways to produce a finished form which may include partial perforations so as to permit easy separation of one form from the next or of one part of the form from other parts thereof. Numbering, imprinting, printing with
bar codes, MICR printing, punching, gluing, placing, etc. processes are typically sequentially performed on the web to produce a finished roll or "pad" of web product. If the forms are designed for later utilization in automated printing equipment, they
typically include so-called tractor drive sprocket holes along the outside edges of the web (with associated partial perforations so as to permit such sprocket drive portion later to be detached). The forms may include multiple layers such as to result
in carbon copies, chemically sensitized copies, or the like.
Heretofore, there have been some limited stand-alone web processors (e.g. a reciprocating numbering tool having "stop and go" paper advancement so as to achieve some depth control). An early "stand alone" bar code numbering unit module including
some features already described in my aforementioned parent applications (e.g. the web drive followed a programmed velocity profile albeit the process drive was free-running) has been producing commercial product since about July 1984 in one of the
assignee's forms processing facilities.
However, for the most part, the complete web finishing process has heretofor been characterized by relatively inflexible processing system design. For example, in some systems, a very complex "line" of processing stations is especially designed
and built into a unitary finishing machine with mechanically coupled process and web tractor drives along the length of the entire machine. Even where "stand-alone" individual web processors have been employed, the tractor and process drive have
typically also been mechanically linked such that only one fixed pattern of web processing operations can be performed without shutting down the machine and physically changing gears, cylinders, rings, etc. so as to set up the machine for a different
mode of operation.
Typically, such web processing operations use web process units having cylinders, rings or the like on which tools or work elements such as numbering modules, imprinters, punches or knives or the like are rotated so as to periodically contact
with and operate on the webs. Such tools typically are of relatively high mass and therefore preferably are rotated at constant velocities. Since a rotational tool is involved, they typically also are "balanced" with respect to the rotational axis.
Since the paper web is then typically also passed through the process at a constant velocity, it follows that only one fixed pattern of web processing operations may be performed unless the machine is physically reconfigured.
Non-limiting examples of some such typical prior art web processing techniques may be found in the following documents:
U.S. Pat. No. 2,549,605-Huck (1951)
U.S. Pat. No. 3,468,201-Adamson et al (1969)
U.S. Pat. No. 3,539,085-Anderson et al (1970)
U.S. Pat. No. 3,561,654-Greiner (1971)
U.S. Pat. No. 4,406,389-Mowry, Jr. et al (1983)
U.S. Pat. No. 4,473,009-Morgan (1984)
U.S. Pat. No. 4,484,522-Simeth (1984)
U.S. Pat. No. 4,528,630-Sargent (1985)
Almost all such prior systems include some "registration" adjustment feature for making fine changes in the relative location of tool or printing press contact with a moving web. Some even use microprocessor-based controls for controlling
registration. Sargent, for example, senses web movement and uses a microprocessor-based system for responsively controlling printing process motions. Morgan uses an infinitely variable mechanical transmission coupled between the web and the process
drivers with the transmission ratio being controlled by a microprocessor-based controller to maintain proper printing registration. However, such "fine-tuning" of the web/process registration is still based on an underlying assumption that, at any given
time for any given machine set-up, only one form depth is to be processed. Mowry does provide an arrangement for handling variable length documents --but still appears to handle only one document length at any given set up condition.
That is, such prior devices generally have been designed merely to repetitively perform only the same process at the same relative registered location(s) on each successively encountered single form depth dimension of the moving web. Thus they
are not truly operator-programmable.
In contrast, the present system is programmable so as to conveniently vary the relationship between process and web drives in accordance with an easily gauged functional relationship. For example, the programmable functions may be chosen to
match the average web throughput of other modules (connected thereto only by slack loops and electrical connectors) and/or to effect successive different progressed form depths between successive process operations.
It has been discovered that a considerable improvement (e.g. greatly increased flexibility in the finishing process, reduced set up time and decreased capital investment) can be realized by arranging an ensemble of modular units to effect a
desired overall web finishing process--and where the web drive within each module is related to its main process drive by a programmable electronic velocity or displacement "profile" and where all of the process drives operate in synchronism in response
to a common electronic "drive shaft".
Some embodiments of an individual stand-alone module are described and claimed in my earlier co-pending parent applications. However, full advantage of the invention is best realized by an ensemble of interconnected modules so as to form an
entire web finishing "line". For example, the modules can be grouped together in clusters so as to form an independent "piece" of production gear or to "speed follow" existing production equipment (arranged to supply, take-up or perform some
intermediate process in conjunction with the assembled cluster of modules) and provide additional web processing capabilities.
Accordingly, a production facility using such clusters of interconnected modules may be custom configured into a great number of different form finishing/production systems by selecting and arranging modules to meet different product
requirements. Each module is preferably mounted on casters for easy portability and movement into and out of any desired manufacturing production "line". The modules can also be clustered in parallel arrangements (e.g. where two different webs being
processed in parallel sub-clusters are subsequently merged or collated into a common multilayered web for further common processing in one or more series arranged further sub-cluster of modules).
Microprocessor-based electrical controls provide a mechanically "decoupled" form of programmed motion control for the web drive with respect to the main process drive within each module. An electrical plug connected bus forms an umbilical cord
to electrically interconnect the modules being utilized within a common "line". The bus connection permits each module's main process drive to be slaved to a common drive pulse source thus making it appear that all of the process drives are driven from
a common drive shaft. At the same time, the bus connections and microprocessor systems are configured so as to permit the entire interconnected system to be operator controlled from the console of any one module and this feature provides great operator
flexibility as well as safety features (e.g. since the process can be stopped, started, etc. from any one of the control panels).
The process being performed in any one module can be programmed to have successive different form depths (e.g. form lengths). In the exemplary embodiment, four different successive form depths are permitted and are initially programmed into the
modules by an operator during a brief preparatory set-up time. Although an individual module may be programmed to have a set of such programmed form depths which is different from other modules in a cluster, the overall sum of all the programmed form
depths in a given module must, of course, define the overall "repeat" period for a given module and therefore should be equal for all modules (assuming, for example, that the process in each module is based upon the same circumference cylinder or the
like). At the same time, use of a "double/normal/half" speed control can cause a given module to effect multiple impressions for each single impression effected in another module and vice versa.
Each module includes a pulse function generator for generating reference pulses which typically each represent a predetermined increment of process drive displacement (e.g., in the exemplary embodiment, one bus drive pulse is generated for each
1/12th inch of process displacement at the circumference of a 17 inch diameter cylinder). In a stand-alone mode, the function generator output is used to provide reference pulses to the main process drive of that same module. In a cluster mode, a
programmed bus arbitration scheme is employed so as to automatically select the module from which the operator happens to initiate operation of the entire cluster as a "master" source of reference pulses transmitted along the umbilical cord bus to
synchronously control the main process drive in each module of the interconnected cluster. As previously mentioned, the system is arranged so as to provide the illusion of duplicate control panels since overall line controls (e.g. stopping, running and
half, normal or double speed or the like) can be controlled from the control panel of any one module.
A special stop interlock system is also employed so as to ensure proper interconnection of the umbilical bus lines. In the exemplary embodiment, if any one of the umbilical bus line input sockets (there are three at the input end of each module
so as to permit plural modules to feed web into a downstream module) is not filled with an appropriate umbilical bus line plug from an upstream module (there is a single "output" umbilical bus line with attached plug on the output side of each module),
then the entire line is incapable of being started or of continuing to run. (Spare "dummy" umbilical cords and plugs are provided at the input side to fill any otherwise unfilled socket.)
In addition, the umbilical cord bus connections are arranged in the exemplary embodiment so as to permit arbitrary bus connection points from one module to the next--provided that one maintains proper in/out directionality for the bus line (i.e.
the output umbilical cord and plug from one module always must be plugged into the input socket of a module--unless it is the last downstream module, in which case it is plugged into a special socket on the output side of the module so as to provide
power for the stop interlock circuit).
Although the exemplary embodiment is described using conventional sprocket tractor drives for the web, it will be appreciated that any conventional web driving mechanism may be employed including tractorless paper transports.
Web displacement is controlled to a relatively greater precision (e.g. 1/480 inch increments) such that the web drive may be controllably advanced or retarded at approximately 0.002 inch increments thereby achieving accurate desired placement of
a process function on the web. Furthermore, since the process tool or the like typically comes periodically into contact with the web (e.g. to effect the desired process), it is typically necessary to "match" the velocity of the web with the velocity of
the rotating tool or the like at the time the tool is expected to actually contact the web. At other times, the web velocity is controlled and may be different from the tool velocity so as to achieve different spacing or intervals between tool
operations upon the web.
In the exemplary embodiment, pre-stored or programmed data comprising velocity or displacement profiles for the web drive are utilized to properly control web drive with respect to the process drive. In the exemplary embodiment, each time a
reference main or process drive pulse occurs (representing another 1/12th inch displacement of process drive), a microprocessor interrupt routine is entered to compute the next required number of web drive pulses (each representing 1/480 inch web
displacement) from stored velocity/displacement profile table data. For example, if the velocities are to be "matched", then 40 web drive pulses normally would be required for each process drive pulse--with different numbers of web drive pulses being
generated if it is desired to slow down or speed up the web in accordance with the stored profile data. In addition, both the main process drive and the web drive are included in a velocity controlled digital/analog servo loop such that the motor drive
is adjusted as necessary to compensate for any detected error between desired and actual sensed velocity/position of the web/process.
The main process employed in any given module may be of virtually any desired type. Some typical conventional processes which may be utilized are as follows:
1. A rotating or reciprocating numbering head;
2. A forms folding module (in this case a "flat" web drive velocity profile would be utilized);
3. A cut off/cross-perforation module;
4. A high resolution dot matrix printer or the like (which may also require constant web velocity if the web is always in contact with the printer process);
5. An unwind/punch module;
6. A rewind module (for rewinding earlier processed forms into an output roll);
7. A collation/fastening module;
9. A diecut module (e.g. for cutting address windows into envelope forms or the like);
10. A lithographic print module;
11. A gluing module for "printing" glue onto forms; or
12. A "placing" module (e.g. for placing credit cards on form or glassine over window diecuts or the like).
Those skilled in the art will no doubt appreciate the fact that there are probably many other kinds of web processes that could be performed in any given module. Nevertheless, as will be explained in more detail below, a cluster of
interconnected modules, all performing coordinated processes, will be controlled to have the same average throughput of web material. Transient variations in web length being processed at a given time in different modules is easily accommodated by
simply permitting a sufficiently loose loop of web material to exist between each successive module in the line.
In the exemplary embodiment, each module utilizes two microprocessor-servo control systems. The main drive servo system controls the main process drive motor which is typically mechanically coupled directly to drive the web processing function
of that particular module. The tractor (or other web drive mechanism) servo system controls the web driving motion so as to meter the correct amount of web travel with respect to process motion. Working together, the microprocessor servo systems are
arranged so as to accomplish the following functions:
1. All module processes are maintained at a coordinated speed;
2. Paper infeed to each process is maintained so as to ensure correct process and web velocity as well as correct registration of the process effect on the web;
3. Form dimensions (both width and depth) may be altered simultaneously on an entire cluster of interconnected modules from the control panel of any individual module in the cluster; and
4. Common press commands such as "stop", "jog", "run slow", and "run fast" may be accomplished by an operator from the control panel of any individual module thus making the entire cluster of modules appear to be mechanically coupled together by
a common drive shaft.
Microprocessor-based motion control systems in each module accept input parameter data and compare them with tables of web operating velocity/displacement profile data stored in memory. Signals to a tractor drive motor thus follow an operating
velocity/displacement profile selected for the inputted parameters.
A tool is driven at substantially constant speed, while the tractors are accelerated, decelerated, stopped and started as dictated by the selected profile. The microprocessor systems each use a reference pulse train and positional feedback
pulses (from rotational encoders) to closely control the motion of the mechanical process/web drive subsystems by comparing actual detected motion to desired motion and output appropriate digital signals which are converted to analog form to control the
process and web driving motors.
Modules electronically coupled together (and/or with other equipment) can perform different web process functions in an independent and yet coordinated manner. For example one module can perform several cutting operations, such as perfing and
punching, and another module can perform several numbering operations, with each module programmed to perform its respective function only, yet synchronized with the other module(s) or equipment as to overall (i.e. average) web throughput.
A cluster of modules can be rapidly reconfigured to build, alter or expand a web processing line without the physical problems typically associated with fixed in-line equipment. The line and modules are to a large degree size independent (i.e. a
wide range of form depth(s) and width(s) can be accommodated under programmed electrical control). Modules may be placed on casters or the like, and a line created by simply wheeling modules into position, plugging them together, and positioning web to
be processed across the modules in loose loop fashion. Any malfunctioning module can be quickly wheeled from the line and replaced. A new line may be created by unplugging unwanted modules and wheeling them away, wheeling and plugging in any desired
additional modules, and wheeling the modules into any desired order. A user may begin with one or a few modules and add modules anytime desired. The modules should find application in traditional business form production facilities, sales offices,
electronic printing ventures, and warehouse form processing installations, among others.
Form depths (lengths) are no longer a significant constraint. Utilizing modules to create forms, forms of any desired depth are possible without change of gearing, rings or the like. Specialized form depths are readily produced without change
of equipment from the equipment utilized for any single, standard form depth.
These as well as other objects and advantages of this invention will be more completely understood and appreciated by careful reading of the following detailed
description of the presently preferred exemplary embodiment, taken in conjunction with the accompanying drawings, of which:
FIG. 1 is a schematic overview of an exemplary stand-alone module;
FIG. 2 is a more detailed view of the operator control panel for the module of FIG. 1;
FIGS. 3A and 3B are graphical depictions of some typical velocity profiles;
FIGS. 4A and 4B are graphical depictions of some typical, displacement profiles;
FIG. 5 depicts a particular configuration of numbering heads disposed on a rotating 17 inch circumference process cylinder;
FIG. 6 depicts a web with successive form depths A-D after process by the numbering heads of FIG. 5;
FIG. 7 depicts the web velocity profile for effecting the forms process depicted in FIG. 6;
FIGS. 8A and 8B depict a typical forms which may be created by processing webs with the module of FIG. 1;
FIG. 9 is a simplified schematic depiction of two serially connected modules;
FIG. 10 is a simplified schematic depiction of two series connected modules connected to speed follow an existing press or collator or other web processing device;
FIG. 11 is a simplified overall block diagram of the tractor servo and main servo velocity control loops and other circuits such as the umbilical bus line and operator console and the like associated with the module of FIG. 1;
FIG. 12 is a more detailed circuit diagram of the microprocessor-based main servo subsystem of FIG. 11;
FIG. 13 is a more detailed circuit diagram of the microprocessor-based tractor servo subsystem of FIG. 11;
FIG. 14 is a more detailed circuit diagram of the Watchdog Doctor subsystem of FIG. 11;
FIG. 15 is a simplified schematic diagram of the inter-module stop circuitry employed in the exemplary embodiment;
FIG. 16 is a schematic depiction of the geometry of a module suited to a folding web process;
FIG. 17 is schematic diagram of the geometry of a module suited for an infeed web process;
FIG. 18 is a simplified schematic diagram of the geometry suitable for a module performing numbering, diecut or imprinting web process functions;
FIGS. 19A and 19B are simplified schematic diagrams of suitable geometry for a perforation/cut off web process module;
FIGS. 20-24 are simplified flow charts of suitable computer programs for the tractor servo microprocessor-based subsystem of FIG. 11; and
FIGS. 25-29 are simplified flow charts of suitable computer programs for the microprocessor in the main servo drive subsystem of FIG. 11.
FIG. 1 is a generalized depiction of an exemplary web processing module constructed in accordance
with this invention. Although the module is typically connected with other modules to form a more elaborate web finishing process line, it is depicted in a "stand-alone" mode at FIG. 1.
An input pad 102 provides a supply of paper webbing 104 to be further processed. In the exemplary embodiment, a sprocket type of tractor drive 106 positively feeds the input web 104 into a conventional web processing station 108 (e.g. a
numbering process where numbering heads 110,112 are rotated at a constant velocity and cooperate with a counter-rotating platen 114 to print consecutive numbers or the like on the web material as it passes therebetween. In the exemplary embodiment, the
active outer ends of the numbering heads 110,112 are disposed at the periphery of an imaginary cylinder having a 17 inch circumference thus defining an active process area each 8.5 inches of circumferential travel of such an imaginary cylinder (e.g. once
for each 180.degree. revolution of the printing head assembly 110,112). The output web drive 116 then positively outputs processed web 104' for stacking in an output pad 102'. In the embodiment of FIG. 1, the output web drive 116 is mechanically
coupled to the input web drive 106 (e.g. by belting, chains, etc.) as indicated by dotted line 118.
The main web process 108 is driven at a constant velocity by drive motor 120 (e.g. via belt driving or the like as indicated by dotted lines 122). The input and output web drives 106,116 are commonly driven by a tractor servo drive motor 124.
Each of these drive motors is included within its own velocity/displacement-controlled feedback loop. For example, a rotary encoder 126 is mechanically coupled to sense the actual position of the main process and to provide an input to the main drive
servo circuit 128 which generates the necessary electrical drive input to the process drive motor 120 so as to maintain the process drive rotating at a constant velocity (as defined by a succession of reference pulses supplied to the main drive servo
circuit from the inter-module bus at 130). In a stand-alone mode, the reference pulses actually are generated by a pulse frequency function generator included within the main drive servo circuit 128 and controlled from the operator's console 132.
Alternatively, the reference pulses at 130 may be supplied from another module or other source via an inter-module electrical connection bus 134.
Similarly, a rotary encoder 136 is mechanically coupled to the web drive 106,116 so as to sense its actual position and to emit a train of representative pulses to a tractor drive servo circuit 138. The servo circuit 138 also receives its
reference pulses from the process encoder 126 and then supplies an appropriate electrical drive signal to the web drive motor 124 so as to maintain the actual web drive at a desired, predetermined but programmable, relationship with respect to the
process drive. As will be appreciated, if the process only contacts the web at certain times (e.g. twice per process revolution if two numbering heads 110,112 are used), then the web drive speed is only necessarily matched to the circumferential speed
of the process at those times. During intervening times, the web drive mechanism may be programmed so as to slow down, speed up, stop, reverse, etc. the web drive so as to ensure that the next process contact with the web occurs at a desired position on
the web.
Operator control and interface with the module 100 (and with any other module 100 appropriately coupled thereto via the inter-module bus 134) is accomplished via a control panel 132 which includes various manually actuated switches and visual
displays (shown in more detail at FIG. 2).
At the output side of the module 100, the inter-module bus 134 extends into an external umbilical cord with connecting plug 140. At the input end of module 100, the inter-module bus 134 terminates in three sockets 142 which may each receive a
connecting plug 140 from an upstream module (or from a suitable "translator" from other conventional devices located upstream or downstream in the web processing "line"). Plural input sockets 142 are provided so that plural upstream modules 100 may be
connected in parallel to a single downstream module with appropriate merging of web materials for further common processing in the downstream module.
A safety stop interlock circuit is preferably also used so as to require a properly wired plug 140 to be inserted within each socket 142 before the module will operate. Accordingly, three additional "dummy" umbilical bus plug connectors 140' are
also provided at the input side of module 100. In case there are any unfilled sockets 142 after a desired cluster configuration has been arranged, then any of the available dummy plugs 140' may be plugged into any empty sockets 142 to complete the stop
circuit. There is also a special socket at the output side of each module. The umbilical cord of the final downstream module is plugged into its own such special socket to provide power to the stop circuit (which is actually a series loop circuit
passing multiple times through all modules). In the "stand-alone" mode, all three of the dummy plugs 140' must be plugged into the infeed side sockets 142 and the umbilical cord must be plugged into its own special socket at the outfeed of the module to
supply 24 volts to the stop circuit interlock.
It should also be noted that the module 100 is mounted upon casters 144 so that it may be easily rolled into and out of position within any given cluster of modules comprising a desired web finishing process line.
The module control panel 132 is shown in more detail at FIG. 2. Here, it will be seen that the left side 202 of the panel permits the operator to control the web process functions via main drive servo 128. The preferred layout of this left half
202 of the control panel is in a format that is more or less "standard" for the printing industry and thus easily understood by most operators. A speed control 202' is also available at the extreme right side of the panel for controlling the main servo
drive speed (at start-up time) in relationship to other module process speeds.
The right half 204 of the control panel 132 permits the operator to program the tractor drive servo circuit 138. As will be explained in more detail below, when a plurality of modules 100 are connected in a cluster arrangement, the module
control panel 132 of any one module 100 may be utilized to control the entire cluster of modules thus giving the illusion of a plurality of duplicate control panels distributed all up and down the process line (i.e. one at each module site).
The speed of the web drive relative to the process drive is controlled by a microprocessor-based servo circuit 138. By manipulating control panel switches at section 204, an operator may select a suitable "velocity profile" or form depth (i.e.
length dimension). This operator selected and programmed profile is utilized by the tractor servo to match the speed of the web with that of the process while the process is in contact with the paper. It may then be used, if desired, to alter the web
speed during the non-contact periods so as to move more or less paper under the process per process revolution. Up to four different sequential form depths may be selected by the operator to define the distances between process functions performed on
the web. The form width simply defines the overall width of the web, and, in the exemplary embodiment, is used to control a transverse tractor drive system so as to space the tractor sprocket drive mechanisms at the appropriate cross machine dimension
for the elongated web product to be processed.
For example, if a successive web numbering process is involved, and if programmed form depths of (a) two and one-half inches, (b) three inches, (c) five and one-fourth inches and (d) seven inches have been selected, the second imprinted number
will print two and one-half inches after the first, the third imprinted number will print three inches after the second, the fourth imprinted number will print five and one-fourth inches after the third and, to complete the overall "repeat" cycle, the
first imprinted number will print seven inches after the fourth.
The process drive h | | |
