Original publication date: April 1992 Heurikon Historical Highlights A series of articles for The Horizon by Jeffrey Mattox The General Electric Company We worked on four interesting projects with General Electric during the early years. Two of them were with GE’s Large Steam Turbine-Generator (LSTG) Division in Schenectady (“Bet-You-Can’t-Pronounce-It-On-Your-First-Try”), New York — a huge factory that makes steam turbines and generators for power plants. One of their critical operations is drilling holes for coolant in the thick copper bars that form the generator rotor coils. Due to the geometry of the generator, each layer of the rotor coil is a different size and shape, but the holes in each layer still have to line up perfectly. GE asked us to build the equipment that would synchronize the numerical data as it was requested by the hole boring machines. The other project with LSTG was a welding machine controller. Most welding machines attach two pieces of metal together, but this one put down a continuous bead of chromium around critical parts of steam valves to prevent wear. Both of those projects used our MLZ-80 processor and a CRT/keyboard controller board. We custom-designed a heavy-duty pedestal enclosure so the equipment was protected from the dirt, metal chips, and oil that pervaded the factory. Another early GE project was with their Housewares Group in Allentown, Pennsylvania. That’s where they assembled their two-slice toasters. Two small calibration screws on each toaster timer had to be adjusted, but the people doing the adjustment had no way to know if they were setting the screws accurately. It could take six hours or more before the timers were actually installed in a toaster and checked, and by that time it would be too late to readjust the setscrews. So, Ben Koltisko, an engineer at GE, having heard about our work from his colleagues in Schenectady, stopped off in Madison to see us on his way back from visiting Intel about his timer calibration problem. After Ben described what he wanted, we offered to make the electronic controls for his timer calibration and testing machine. We proposed a system that had features Ben hadn’t even thought of but realized he could use. Intel, however, merely offered a basic microprocessor, and they wouldn’t do any custom work. Because we fully understood his problem from the get-go, he gave us the order. As with many projects, we were caught short on the schedule and had to innovate. For example, when we couldn’t find anybody willing to give us a short turn-around on finishing our 25 small enclosures, we took the raw computer boxes across the West Beltline to an automobile-painting company — the people there were much more accustomed to repainting vehicles and doing pin stripes, but they obliged us anyway with overnight service. The interesting part about a toaster timer is that it has to account for the residual heat inside the toaster so that the second and third toasting works as well as the first. No small trick. The mechanical timers were really two-cycle thermostats. When you started toasting, a bimetal strip was heated to a set temperature by a special heating coil. When that set temperature was reached, the thermostat clicked, the special heater went off, and the thermostat cooled down. After it cooled sufficiently (to the second setpoint), it triggered the pop-up solenoid and stopped the toaster. That click you may have heard when your toast was almost done was not just a warning for you to get ready with the butter knife; it was actually part of the timing operation. A few years ago, GE’s Housewares Division was purchased by Black & Decker, and the toasters are now sold under that name and made in Taiwan. The reassuring timer click is defunct, too — probably the result of having gone solid-state. The Versatron Toaster-Oven Our fourth GE project was for another toaster-like product, called the Versatron Toaster Oven. It had a control panel with an assortment of buttons, levers, rotary switches, neon indicator lights, and audible alarms. Our task was to build the computer controls for sequencing a pneumatic machine that would fully test all functions of the control panel, including the switches, lights, and alarm. The operator loaded a Versatron panel into the machine and the tester grabbed hold of the switches and went through a sequence of tests, monitoring the panel’s outputs, lights, and alarm. The unit even had a bed of nails, much like our Genrad. The machine took about 45 seconds to test one panel, and the mechanism clicked and clanked and hissed the whole time. Very impressive. But alas, just when we got the unit finished, GE pulled the Versatron off the market. They had started selling the toaster-ovens before they had put a service network in place, and the ovens were not operating as planned — too many needed service. The ovens were being returned for repair faster than GE could fix them. So, they paid us for our work, took the testing equipment we had built, and, for tax purposes, fed the ovens and our testers to a trash compactor (ouch!). |
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