Testing boards for quality

Introducing smart solenoids into car alarms has necessitated a new set of tests for the hybrid board on which they are mounted. A production line capable of automatically handling a variety of tests for these hybrid boards has been designed and constructed by CPR Automation.

The function of the line is to pass each hybrid through a series of tests involving: a pin alignment test; heating to 125 degrees C +/-5 degrees C; functional test; printing of barcode; verifying the barcode is correct; cooling to ambient temperature; and finally placing the hybrid board into a transport package.

Hybrid packages are delivered direct to the line following an hermetic test. Once they have passed automatically through all the stages of the line process, they are sorted and placed into the correct storage tray. The only operator involvement is to load empty trays to the packing area and take them away when they are full.

At the start of the line the boards are collected from a chute in the correct orientation. They are then transferred to a walking beam which conveys them through a set of heating blocks to raise their temperature to 125 degrees C +/-5 degrees C.

Once at temperature, the packages are transferred to the test station. Here, a linear slide locates a set of test probes, connected by flying leads to the test equipment, against the board’s pins. To prevent damage a non-conducting back stop is provided for the pins to counteract the bending forces exerted by the probes.

The line is capable of handling up to 400 tests/hour and the final result for each board – pass or fail – is stored on a simple mechanical data tag and read at the print/reject station. It is used to trigger either the inkjet printing of a barcode on the board, or its ejection from the line. Using a mechanical tag allows the test result to be stored and read regardless of whether there is power available or not. It also permits the result to be seen and verified.

When the hybrid boards have been tested and coded, a cooling section restores them to ambient temperature, before they enter the packing/storage station. A storage tray is placed in each zone and is filled by an X-Y robot arm.

CPR Automation Tel: 01827 57475