Injection Moulding

How does an Autoloading Hopper work?

  • Posted by Mark Serisier
  • October 5, 2018

How does an Autoloading Hopper work? An autoloading Hopper is just like a regular hopper, except that it can load material from storage bags around the machine. It does that by using a vacuum placed on top of the hopper.

This vacuum is caused by a fan, connected to an electric motor. As the fan spins it sucks air out of the sealed hopper chamber, causing a significant drop in pressure. The lower pressure wants to equalize with the air around it. This happens with the air from the hose connected to the excess material in the storage bags. The air in the tube rushes up the tube, trying to equalize the pressure. The air carries any plastic granules up with it, filling the hopper.

Different autoloading hoppers are actuated differently, most are activated when the weight in the hopper falls below a certain level, causing the electric fan to kick in. Some hoppers can be programmed to top up the hopper periodically by manually inputting the required weight and period between suction. Other more advance systems talk to the injection moulding machines and calculate how much to fill up the hopper with by analyzing the injection moulding shots and cycle time.

It’s best practice to set your hopper to load several shots worth every time they load plastic into the hopper. This is more efficient, as you get a load of material every few minutes. This will help to reduce your maintenance on the fan, as it’s not turning on an off every 30 seconds. It’s also slightly more efficient from an electricity consumption point of view.

If you’d like to learn more about hoppers, please don’t hesitate to contact us about a free 1-hour meeting.