Application example: Motion components on a typical form-fill-seal machine

Form-fill-seal machines are used to package edible powders, dry food, and liquids into bags and pouches. It’s a common machine design that comes in versions for both continuous and intermittent operation. No matter the design, top design objectives for form-fill-seal machines are high throughput with minimal downtime and the ability to reconfigure the machine to satisfy changing production requirements.

Mitsubishi Electric Automation Inc. offers an array of solutions in its Pak/iQ suite to improve the builds of such packaging equipment with reliable machine performance and communication of system analytics for IIoT functionality.

Consider the build shown in the illustration.

Bulk food product enter from the top as servo-driven axes pull bag material off roll stock (spools). The funnel hood shapes the plastic sheet into a cylinder. Then a thermal heat sealer melts together bag edges; bags are filled from above as the web travels downward. Vertical film index drives time this function to match the machine’s operation cycles. From there, the bags get their final cutting and sealing — and then go onward to conveyors that carry them away.

On this machine, a PLC (in the form of an iQ-F compact controller) provides necessary functions while helping OEMs keep cost down. Programming of the PLC is through simple parameter setting: iQ-Monozukuri Packaging software gives engineers sample programs, sample GOT HMI screens, and auto-generated function blocks — including those for rotary-cutter, camming, long-dwell, flying-shear, box-motion, and mark-detection tasks.

To command and drive the motion tasks, the machine build uses an FX5 Simple Motion controller, MR-JE Series servo amplifiers, and (on the conveyor) an FR-E700 Series VFD. Two of the MR-JE Series servos are for web-index control; one is for the sealer axis. The three servo-driven motor axes are networked through fiber-optic-based SSCNETIII/H. Servo-network refresh rates to 0.222 msec allow accurate control.

Capabilities of Mitsubishi-outfitted form-fill-seal machines include auto-generated function blocks for camming as well as advanced synchronization that’s easy to configure … for fully synchronous multi-axis performance. The hardware also allows for direct control of the VFD from the HMI.