The modern drives high revolutions need the highest accuracy when producing crankshafts. Quality control is a mandatory. One of the testing jobs is length measurement for the attainment of measuring values in described intervals on the rotating crankshaft. The measuring machine can be inte¬grated straightly in a separate test room or in the manufacturing process.
A SimaticS7 controller manages the crankshaft test station. Additionally to the standard inputs and outputs for light barriers and valves, other I/O, for instance, for an incremental shaft encoder, are needed for testing the crankshaft. The shaft encoder provisions suitable information on angles for recording positioning on the turning test item. The point of view data is then allocated to the appropriate measuring value. The simul¬taneous achievement of the position and the surface allows the work piece to be corrected accurately where the faults of surface are actually there.
This calculation-exhaustive job can only be applied with a PLC at conside¬rable cost and depends, along with other things, on the cycle count.
What the equipment of electronic measuring has to be able to do
• Record surface quality concurrently and position in sequence to be able to carry out precise corrections at known fault sites
• Compute minimum and maximum average values or values in sequence to categorize any abnormalities within or outside a predefined acceptance or to relieve the load on the PLC
• Be arranged directly in the production hall near the test unit
• Work dependably at high temperatures and with splatter water
• Easily link to the PLC
• Correspond via standard Ethernet in order to also forward values to the IT level for punctual measurement of pro¬duction quality
• Carry out parameterization without programming, for instance over an integrated web interface
• Carry out diagnostics and monitoring without SPC or special programs