Autoinjector test equipment

As a final part of the assembly process of autoinjectors, key parameters such as injection time and needle depth are tested. In this connection, TPU A/S has developed a test fixture with associated software that enables time measurement of the injection and distance measurement of the needle optically with a machine camera controlled by a PC. Combined with the customer's own tensile test bench, the test fixture can also be used to measure the force to remove the safety cap, the activation force, as well as the needle protection force. Thus, the main parameters of the autoinjector can be tested on one pen, thereby reducing the total number of pens to be tested. 

When the pen is activated, the recording starts automatically and after the injection is finished, the program analyzes the images using machine vision functions to find the coordinate of the needle tip as well as the start and end time of the injection. The operator has the option of playing back the recording frame by frame and, if necessary, correcting the start and end time as well as selecting which frame is to be used for determining the needle length. 

After the end of the test series, you have a series of images for each test and it is possible to print the found needle lengths and injection times to a PDF as part of the documentation package for the test series.