The customer’s goal was to automate the entire process involved in overmolding stators—from preparing and preheating the parts, to loading them into the injection molding machine, to removing and unloading the finished overmolded components.

To this end, a well-thought-out automation concept was developed: A robot was positioned centrally in a cell next to the injection molding machine, and all peripheral devices were arranged functionally around this robot. The system includes, among other things:

• A large-capacity magazine for the untreated stators, which can be manually reloaded during operation,
• An inspection unit for checking the overall height (number of layers) of the stators,
• A specially developed heating unit for preheating the inspected parts,
• The automated loading of the stators into the injection molding machine, and
• The removal of the finished overmolded stators and their space-saving placement on a wide discharge conveyor.

A central element of the system is a sophisticatedly designed double gripper with a dual gripping function. This allows the robot to simultaneously remove the overmolded parts and load two new stators when the injection molding machine opens. In this way, the mold opening time has been reduced to an absolute minimum — it now takes only a few seconds.

The workflow is as follows: The robot retrieves two parts (stators) from the magazine, then moves to the inspection station and checks their height; this ensures that the stators have a sufficient number of laminated sheets. If the inspection is successful, the two parts are placed in the heater — otherwise, the non-conforming parts are ejected via a chute. The heating unit is also a custom-designed solution that features two slides at the top to minimize heat loss as much as possible. The heating unit can accommodate multiple parts.

The robot then picks up two preheated parts and moves to the injection molding machine. After the mold opens, it first removes the two parts to be overmolded and inserts the two new parts. The mold closes, and the parts are overmolded. Meanwhile, the robot places the removed parts on a conveyor belt. The belt can accommodate many parts, ensuring high autonomy; they can now cool down and be removed by hand.

A new injection molding machine was purchased specifically for this customer order. A unique feature: The machine was delivered directly to Soldati AG to ensure the complete commissioning of the entire system on-site under real-world conditions — an approach that enabled comprehensive functional testing and optimization in-house.