Fully automatic testing system for auto-injectors

				PIA Fact Check
			
			Space-saving overall solution
Fully automatic testing
Configurable for different injectors

Fully automated test procedures with the smallest possible space footprint

Precise testing technology for the highest quality standards

Not every injection has to be given in a medical facility. There are a number of medications that patients can inject themselves. The demand for such auto-injectors is increasing worldwide, partly because lifestyle diseases such as diabetes are still on the rise and partly due to cost pressures in the industry. Understandably, medical products are subject to particularly high safety and functional requirements. This is why a renowned customer from the pharmaceutical industry relies on a fully automated testing system from PIA Automation for the quality control of such injectors.

The use of autoinjectors, which are filled with medication for the treatment of diabetes or rheumatism, for example, is very simple for patients: the cap is removed, the plastic cylinder is pressed against the skin and, when a defined pressure is applied, a fine needle emerges from the tip and injects the medication under the skin.

Product criteria are faultless function and absolute safety

The PIA customer produces large quantities of these autoinjectors every day. Employees take random samples by hand, which the PIA system checks fully automatically for various safety and function-relevant parameters. The employees place the autoinjectors horizontally in trays. A fully loaded tray trolley contains eleven trays with up to 400 injectors. The fully automated testing process begins when the first tray is moved into the system. A gripper removes an autoinjector from it and takes it to a custom handling system with a gripper. This rotates the injector 90 degrees into a vertical position and inserts it into the first station, where the protective cap is removed. The gripper picks up the ready-to-use injector again and transfers it to another handling system, which inserts it into the test station. There, a servo press triggers the injection mechanism.

The test station measures the force for triggering, the distance the pen is compressed until activation, the time from the start to the end of the injection and the amount of active ingredient dispensed. The autoinjector dispenses this into a measuring cup. The station also monitors whether the needle is intact. A visual indicator on the autoinjector signals that it has been used and emptied. This mechanism is also monitored by PIA’s equipment.

To prevent users from injuring themselves on the extended needle in real-life use, the injectors extend a needle shield after dispensing the medication. The system also checks the blocking force of this protective mechanism and tests whether the needle shield holds securely under high pressure.

Maximum precision for minimum tolerances

"The system's measurements are very extensive and have to be extremely precise. Medical products only allow minimal tolerances and absolutely reliable processes," says Ramona Neulinger, Project Manager at PIA. The values for release force, travel and pressure on the needle guard are measured by a servo press. The visual inspection of the needle, drop formation and emptying indicator is carried out by two camera systems that record 500 images per inspection process. The precision scale for measuring the amount of active ingredient dispensed has a resolution in the milligram range. The scales are structurally decoupled from the rest of the system in order to eliminate measurement errors caused by vibrations.

After the inspection, the handling gripper places the injectors back in the tray. If a random sample shows any abnormalities, it is diverted and kept in a separate location, ready for a manual follow-up inspection. Because each autoinjector produced has an individual DMC code, the path of a defective device can be clearly traced back through production.

Configurable for different autoinjectors

With the machine, PIA is continuing a successful client relationship that began in 2010. Since then, PIA Automation has developed and installed several assembly and automated test systems for this customer. A particularly innovative feature of the new system is that it can be configured for more than one type of auto-injector. The customer is initially planning to test two types of auto-injector in the system. The scope of delivery also includes calibration equipment, which is used to test the system and the function of the test processes at specified intervals. The equipment includes various weights to accurately calibrate the precision scales.

"The joint development of the system once again demonstrates the excellent cooperation with the customer and a functioning simultaneous engineering process," Ramona Neulinger, summing up the current project. One of the customer's requirements was to develop the system for the laboratory in as little space as possible and to implement all testing processes in a very confined space. "We were able to meet all the requirements. We constantly monitored progress in weekly meetings and continuously developed the system design on the basis of the results already achieved," says Ramona Neulinger.