Measuring closing force with a universal testing machine

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This test measures the force required to close a lid on a travel coffee mug.  We used our eXpert 2610 universal testing machine to perform the test, but it would have worked just as well with one of our smaller single column eXpert 7601 or eXpert 5601 testers.

This test is very simple- the compression platen moves down to press the lid onto the coffee mug and measures the peak force required to close the lid.  However, the technology required to perform repeatable testing is complex.  The closing event happens quickly so you need to record the data very fast.  For this test our data collection rate was 1000 Hz, or in other words, we took 1000 load and position measurements every second.  The peak load measurement is significantly impacted by the speed of the test.  Therefore, a servo controlled testing machine is required to maintain a constant testing speed (in this case 10" per minute).  Servo control senses the slow down in speed caused by the load of the test specimen and tells the motor to move faster to keep the speed constant.

This type of test is applicable for a wide range of products.  A few examples we have tested that are similar in concept are: automotive center console lids, headphone jacks, and consumer goods packaging.

You can see a video of the test below.