Urania

Ink roll coding onto the pouch material is an option for data that remains constant during operation (i.e. lot number, expiration date). The ink roll coder cannot handle serialized or variable data. Because the ink roll coder type is pressed against the pouch material, the placement of the message is restricted to the area above the actual heat seal. If the ink roll coder was below the seal, the type could perforate the pouch material and compromise the pouch integrity.

Some advantages of pouch ink roll coding are:

1. Reliable operation.
2. Relatively low cost.
3. The only consumable item is the hot ink supply roll.
4. Since coding occurs at the exit of the sealer, any rejected pouches will not have an inked code.
5. Ink colors are available to provide good contrast between ink and background pouch material.

The ink roll coder mechanism is comprised of five main components: A ink roll coder frame, a rotating type wheel that holds the information to be ink roll coded onto the pouch, a heating element to heat the ink supply roll and the rotating type wheel, a electrical clutch mechanism that prevents the type wheel from rotating when it is not needed, and a pressure roller used to provide backing to the ink wheel during coding.

The ink roll coder frame provides a mounting base for all other components. The frame is attached to the sealer by two standoff rods located downstream from the sealer cooling bars. The frame slides down these standoffs until the ink roll coder driven gear engages the rear sealer drive gear. A small four-pin connector on the frame provides 24VDC power to the ink roll coder clutch mechanism and 115VAC to the ink supply heater and plugs into a socket mounted on the sealer head.

The ink roll coder utilizes a doubled-sided type wheel. For proper operation, the ink roll type wheel must be loaded with two sets of type, one on each side of the wheel. Otherwise, every other pouch would be marked with ink.

To change an ink roll coder message, the operator must first open the sealing head cover. Then, they may lift the entire ink roll coder mechanism out of the sealer. Since the ink is heated, all components of the ink roll coder must be considered hot at all times. Use insulated gloves to handle the type wheel. The rotating type wheel features a quick-release mechanism to allow easy removal of the type wheel. Once removed from the ink roll coder unit, the operator can remove the silicone rubber stops that retain the characters in the type wheel. Once the type has been changed to the new message, the operator replaces the silicone rubber stops and replaces the type wheel. The ink roll coder then drops back into position, and the operator closes the sealer cover to resume operation. As an option, the customer may purchase a second type wheel and have the next set of ink roll coder type ready for a very quick changeover.

In order for the touch-dry ink to transfer to the pouch material, the ink supply roll and type wheel must be heated. Two small 115VAC heating elements are incorporated into the ink coder unit, one on each side of the ink supply roll. A thermostat regulates the temperature at an optimum level for operation and prevents overheating. As each pouch passes through the ink coder, the opposite side of the type wheel contacts the ink supply roll. The type is re-inked for the next set of pouches. This would be considered an "offset" type of print.

The Programmable Logic Controller (PLC) in the sealer control panel operates the ink roll coder clutch. The PLC detects the presence of the pouch with the same optical sensor used to count the number of pouches passing through the sealer. Once the leading edge of the pouch is detected, the PLC runs an adjustable timer to delay the activation of the ink roll coder clutch. The ink roll code position on the pouch can be adjusted by changing the amount of delay time. The offset is in inches from the leading edge of the pouch, and the PLC automatically converts the distance to time, based on the actual speed of the sealer. The position of the ink roll code can be adjusted from zero inches from the leading edge of the pouch (0.000") to a maximum of thirty-six inches (36.000"). The actual positioning of the ink roll code is accurate to within one-eighth of an inch (+/- 0.125").

When the pouch is in correct position for ink roll coding, the PLC sends a 24VDC signal to the ink roll coder clutch to activate the clutch release solenoid. The solenoid releases the clutch, allowing the type wheel to turn at sealer speed. The ink roll code wheel rolls the type against the pouch material, creating the code on the pouch.

The final component of the ink roll coder is the pressure roller. This roller is covered with a durable silicone rubber and is allowed to freewheel on a set of ball bearings. As the pouch enters the ink coder, it is sandwiched between the pressure roller and the type wheel. A small gap between the pressure roller and type wheel allow the pouch to pass between the two parts. The type characters extend out from the type wheel and press the pouch against the pressure roller. The rubber covering allows the type to properly transfer the message onto the pouch material.