Good points, LloydP. In 2008, the automation industry was wringing its hands over the boomers retiring. Then the crash happened. 401s tanked and thousands of engineers put off retirement. But it has got to be a problem. I was talking to a vendor who noted that the last engineer who knew how to shut down a utility plant had retired. They had to hire the vendor to teach the control engineers how to shut down the plant.
Haven't you people heard of a ground fault circuit interrupter? If you had one in your main fuse box (mandatory in some enlightened countries) it would have cut the power as soon as the fault occured. (it trips when there is an imbalance in the phase and neutral currents, which would happen if current flows to ground).
I have seen nichrome coils break in an electric-range oven and in a toaster. Failures happen.
I'd be surprised if the dryer didn't include thermal cut-off sensors. A company called Klixon makes a wide range of accurate thermal switches and I've seen them in dryers. When the temp gets above the switch's limit, power shuts off. The next time you open a dryer for repairs--usually a broken belt--look for temperature sensors on the exhaust tube and on the dryer compartment. They should be there.
"In reality, the cause of the problem that you describe is almost always indicative of a long-term clogged vent or lint filter."
Very true. Don't forget to inspect the vent line for obstructions when you relocate to a new home/apartment.
Upon doing my first load of laundry in an apartment which I had just moved into, I had a brand new electric dryer run very hot (saw red coming from the coils underneath).
Upon inspection I found wadded up plastic groacery bags shoved down the vent tube to stop cold air entry during the winter.
Sad thing was that the apartment had been the complex's office until a new office/pool building was built. That showed how much pre-inspection was NOT done by the "maintenance" person. Had this been any other apartment with the same issue and a less than aware tenant, the issue probably would have caused a fire for the entire building.
Did the issue do damage to the dryer? I don't know. Since the washer/dryer was provided by the management in the rent package, I did not really care.
The dryer still worked 3 years later when I sold the units.(This was after the management removed the washer/dryer in rent provision package, I had moved to a different building and apartment unit [moving the washer and dryer under the old lease terms], and finally the complex was sold and changed management firing all the prior management maintenance/office personnel. At my final checkout inspection from the complex, the new manager said that if I didn't remove the units I would be charged a clean out fee. Of course I said "Sorry, my friend was late to pick the washer/dryer up with his pickup." The units were removed post haste and I received my entire deposit back... )
Actually, open nichrome heating elements, with their superior heat transfer characteristics, have been used with very few problems since the electric dryer was first invented. Before blaming the engineering (I have seen these machines in use for more than 50 years and still going strong), ask yourself about your maintenance habits. Clothes dryers, both gas and electric, should be cleaned of lint at least once a year. The residue of modern synthetic fabric materials that escapes around seals and clogged lint filters is much more flammable than that of cotton or wool. In reality, the cause of the problem that you describe is almost always indicative of a long-term clogged vent or lint filter.
I doubt that there is a "wealth of engineering knowledge" behind any of these products anymore. Most of those with that wealth of knowledge have been retired (if they are lucky), downsized, outsourced, or just plain let go. That's the way it is with the employer I retired from with 30+ years of design experience.
Both GM and Chrysler (disclaimer: I was an engineer at GM in the '80s and '90s) are now desperately trying to hire skilled engineers to repalce the ones they let go over the past 5 years. They can't find people with the skills they need, at the wages they are willing to pay.
Since this is not a common problem, I suspect an isolates assembly error or a one time faulty part. So we probably have just one Monday morning monkey.
1) The FIRST thing you must recognize is that KENMORE is a SEARS, ROEBUCK brand. They do not manufacture appliances. For the past 40 + (maybe 50+) years your good friends @ WHIRLPOOL have been the manufacturer of the KENMORE washers & dryers & other large appliances. So, it is more fitting in light of the many negative posts here to blame the WHIRLPOOL CORP. for shoddy engineering / design.
2) With the increased complexity and feature lists of modern appliances, it seems entirely reasonable that a particular model might have been designed w/ effective & high quality sensors to start, BUT when the "value engineering" group got together w/ the "bean counters", many of these sensors got "dumbed-down" in quality, ultimately leading to premature failures. It would NOT have surprised me to be able to view the ORIGINAL design for the heating elements section and notice that there were several more ceramic standoffs in place, BUT ........
3) We had a HAMILTON (natural) gas dryer along side a 1950s era LADY KENMORE washer, which served the needs of the family for several decades WITHOUT one hint of trouble. The end came eventually for both but it was not after they racked up countless thousands of cycles. The HAMILTON dryer failed for a part in the gas delivery system, but since HAMILTON had gone out of business, there were no replacement parts available. The KENMORE washer had a totally fatigued transmission. Although replacement parts were available, we splurged on an updated model.
Good to hear that was an old model. I am about to purchase a new dryer. I actually hate buying new appliances all together. It seems every replacement lasts less and less than the one before it. Whether it be poor design or build quality, or that they just have more to go wrong with them.
One thing that I must not have made adequately clear is that this occured over 20 years ago to a dryer that was at least 10 years old, as best I can recall at my advanced age. We have had many Kenmore appliances and for the most part they were very well built and reliable. This situation was an exception, but still an example of poor design.
For 3D printing to make the jump from rapid prototyping to manufacturing, engineers will need to find easier ways to move products from their CAD screens to their printers.
Gigabit and PoE are two networking technologies moving ahead in tandem as industrial users power remote Ethernet devices such as IP security cameras at 1,000 Mbps over existing CAT5 cable.
New versions of BASF's Ecovio line are both compostable and designed for either injection molding or thermoforming. These combinations are becoming more common for the single-use bioplastics used in food service and food packaging applications, but are still not widely available.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 5
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
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 radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This
2 
