Beat that for simplicity! 2

[Skogsgurra]

There was a question here a year or so ago. It was about opening and closing a flap (waste gate?) in a car. I sketched a solution that, in my view, was simple and reliable. The OP came back and said it worked well.
I made a small application note and sent it to the "Idea for Design" department in the Electronic Design paper. Their criteria for acceptance says: "Non trivial and not too simple" - I thought that a simple incandescent lamp was too simple. It is, after all, the simplest circuit there is in starter kits like "The Little Electrician".

I forgot about it and was very surprised when I got mail from a guy named Lliam where he thanked me for the solution to a problem he had. Nice and surprising. Maybe it wasn't so simple after all?

http://electronicdesign.com/components/lamp-eliminates-need-limit-switches-flap-motor-control

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[itsmoked]

Hilarious. I read that article in print about 2 days ago but never looked at who the author was.

Congrats.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[waross]

Yes the lamp is simple. Recognizing the application is where the genius resides.
Nice, Gunnar.
Yours
Bill

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[VEBill]

Congratulations.

Do they still send you the little $100 honorarium cheque?

 

[DRWeig]

Sharp, Gunnar. Congratulations!

Best to you,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies

 

[ScottyUK]

Nice solution - meets the requirements very well. My only reservation is the inevitable filament breakage, and the effect of losing power to that valve might have on the engine.

 

[jraef]

Well, the lamp is in essence being used as a PTC thermistor, kind of in the opposite way we use NTC resistors for inrush current limiting. If you don't like the simplicity of the lamp because of the susceptibility to vibration of the filament, you could likely find a similar PTC thermistor if you looked long enough.

"Will work for (the memory of) salami"

 

[bradrs]

Very clever way to simplify the circuit.

I guess for this application, any effects on the open/closing time are not that relevant? Depending on usage, that could create a slightly larger boost spike as the wastegate is being controlled.

 

[OperaHouse]

EICO was selling kit transistor amplifiers in the early 60's. They had an ad that showed a light bulb. The heading was, This is the only piece of test equipment you need. My bench has had that series AC lamp ever since.

My favorite lamp circuit from Electronic Design was an AC voltage regulator that used three resistors and a lamp in a bridge. We built a product that required a trip at 20mv either AD or DC. The rule there was never spend more than $20 on a test fixture. It didn't matter as to the engineers time. I remembered that circuit and the voltage out was rock solid form a power line of 90-135V. That is impressive for just a lamp. I fed the DC through the same circuit and switching from AC to DC produced the same voltage.