Because the factory is in high production mode, quality control has to be able to keep up. There are multiple dimensional gages measuring at the same time, and all of the data are routed into computers through multiplexers set up nearby. The largest number of gages Mohr has connected to a single multiplexer is eight, but he noted that the environment determines that number rather than the instrumentation. Each gage is assigned a channel, which is sent as part of the serial output on the multiplexer. The MPX multiplexers have their own software, which transfers the information from their serial ports into Crown s statistical software.
Quality control can then run reports and create charts and graphs based on the real-time results.
Installing the multiplexers was a bit of a challenge, not because the instrumentation was complicated, but because it was necessary to interface the boxes with the statistical software carefully. The multiplexer will provide the measurement data to the software, but the software has to know where to collect the information from the various channels on the multiplexers. Also, Crown wanted to sequence the multiplexers to reflect the gaging process. To do so, the multiplexer box and software had to be correlated so that when an operator triggered the box, he accessed the correct gage. If you had multiple gages, and you were looking for a number, and somebody happened to hit the wrong switch, it may have triggered a different gage.