Not letting folks know about the filter changing requirement is the one way that they have of keeping those totally unqualified fingers out. And there are a lot of folks so inept that they cross-thread lightbulbs. Of course, some companies go way overboard, like the five-point anti-tamper screws on a seagate external hard drive. They were a pain to remove, but I did remove them and replaced the failed hard drive. Possibly some of it comes from a desire to avoid litigation for somebody injuring themselves, inept people do that a lot.
But on that dishwasher, the well designed ones use a different system to avoid the need for filter cleaning. And some of the other good ones make the filter easy to find. That may be part of the difference between an older expensive unit and a current cheap one.
Not qute designed to fail but it sure is hard to not be paranoid about the failure to tell the user that there was a filter that had to be serviced periodically so some repair person could charge an outrageous sum for a trivial service operation.
That is an evil monkey at work not a dumb monkey like the second issue with the blower.
Maytag is not the only company to cut a corner on squirrl cage blower designs. Our whirlpool dryer, and the one belonging to a friend, also developed the rubbing blower syndrome, but the fix was not that easy. It seems that the main blower is only connected to the drive shaft by a rather weak spring clamp, with no means of positive attachment. But the blower is not perfectly balanced, and not immune to the accumulation of a bit of lint, since it is downstream from the drying clothes. What happens is that the blower wheel vibrates just a bit on the shaft, which the atachment is a split hub made of the same nylon-type of material. The result is that there is wear, resulting in greater clearance, resulting in greater vibration. Eventually the wear will reach the point that the blower wheel no longer engages the shaft, and so it does not spin, resultingin no airflow, which leads to an overheating condition, which causes the non-resettable overtemperature device to open, leaving the system non-functional. The only repair is replacing the blower wheel and the overtemp protection device, which are accessed from opposite acess points on the dryer. But that does not eliminate the problem with the drive connecton to the blower wheel, which the replacement is not improved from the original design. The (sort of) fix is adding a screw type hose clamp in place of the weaker spring clamp, although a real fix would be a solid hub, close fitting, and a different design to keep it on the shaft, such as a bolt in the end of the shaft and a cup-washer to clamp the hub. BUT of course that would mean changing the design and adding a production step or two. Better quality does cost more to build, it seems.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.