Eyemark Technical Support
MARK I - Intermittent Motion
MARK II - Continuous Motion - Advance and Retard
MARK III - Continuous Motion - Correction by Retard Only
MARK IV - Continuous Motion - Correction by Advance Only
By means of a reciprocating jaw, rack and pinion roller, or other draw device, the web or fillm is intentionally fed slightly longer than the distance between two registration marks. For example, if the repeat length of a printed design is 16 inches, the feed length might be set to 16 1/4 inches. The overfeed guarantees that the printed registration mark will reach the photoelectric scanner, even if a limited amount of slip is present. When the scanner detects the mark, this indicates that the proper length has been reached. A signal is sent to the disable of stop the feed mechanism. This will cause a reciprocating jaw to open or activate the brake on a gear driven feed assembly.
Registration components for Mark I Operations
Method of Operation
The packaging machine is set to feed a precise length of material from a continuous roll. This length matches the repeat length (mark-to-mark distance) of the printed design as closely as possible. The feed errors are minor but cumulative. Without registration control, the machine will produce about 10 packages before correction is needed.
When this condition is met, a relationshop is established between the printed design and the machining cycle. The desired position of the registration mark is constantly compared to the fixed machine cycle through machine-operated timing switches. It the scanning signal arrives early, a correction signal is sent to retard the rate of feed. If a scanner signal arrives late, a correction signal is sent to advance the rate of feed. The machine operator sets the duration of this correction.
Registration componenets for Mark II operation (click Model 5E)
(A.K.A “Feed long, correct by shortening”)
Method of Operation
This registration control system has been designed to reduce the complexity of packaging feed mechanisms by combining the essential functions of length control, fine feed adjustment and registration control. Although originally intended for use on machines using change gears to set the draw (the cut length of the web or film), it is easily adaptable to most feed mechanisms.
Because of the limited number of gear combinations, the variables of a printed material, and the mechanical limitations of machinery, it is likely that any setting or selection will produce an off-sized sheet. The resulting length will be either slightly too long (overfeed) or slightly too short (underfeed). The Mark III system is designed to compensate for intentional overfeed.
Through either a selection of change gears or the setting of a variable drive, the machine is set to produce an -oversized sheet. It should exceed the printed repeat length (mark-to-mark distance) by approximately 3%. A printed web, film, or foil having a 12” repeat length should be fed at the rate of approximately 12 3/8”. The flexibility of the system allows this to vary from 12 1/8” to 12 5/8”.
The excess length is eliminated by reducing the speed of the feed drive mechanism (rollers, fin wheels, etc.) for about half of each cycle. Simply stated, the overfeed of direct drive (advance) is counteracted by an appropriate amount of underfeed from reduced drive (retard).
Direct Drive — the feed roller is driven at the intended overfeed rate. As described above, this overfeed should be approximately 3%. If this rate continued for a completecycle, a 12” sheet would be fed at the rate of 12.3 inches per cycle.
Reduced Drive — the feed rate is reduced 6% through the mechanical action of a retard-only differential (Model 803 Rotary Compensator). If this rate continued for a complete cycle, the 12.3” sheet from the direct drive would be reduced to 11.5”.
Length Control and Fine Feed Adjustment — By means of an adjustment on the Model 804P Selector Switch, each machine cycle is separated into a period of Direct Drive and a period of Reduced Drive. A balance is established that produces a sheet of almost perfect length. This balance is established purely by mechanical means and does not require electronic monitoring. For registration control purposes, the ideal setting will allow an extremely minor overfeed (advance).
Registration Control — After the feed has been adjusted as described above, the final task is to monitor and control the intentional minor advance. This is accomplished by locating a known point on the printed web, film, or foil and comparing it to a known point in the machine cycle. When the accumulated advance reaches a set limit, the period of the Reduced Drive in momentarily increased. By temporarily increasing the duration of the retard, the printed design is returned to the registered position.
Registration components for Mark III operation (click Model to 5E)
(A.K.A “Feed short, correct by lengthening”)
Method of Operation
This type of registration application is similar to the Mark III system, with the following exceptions. Instead of setting the change gears or variable transmission to overfeed, an intentional underfeed is used. Registration control is accomplished by adding a slightly longer sheet. As with the Mark III system, a photoelectric scanner monitors a point in the printed design of the web, film, or foil and compares it to a given point in the machine cycle.
Registration components for Mark IV operation
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