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Variable speed windshield wipers

OK, so this won’t reshape the world, but why doesn’t anyone make a true, variable-speed windshield wiper? You know, with a real variable speed dial that went from 0 to whatever full-speed is. I know it would work with the DC power system, because the torque is pretty constant across speeds.

The added bonus would be that in addition to getting the perfect speed for keeping up with the drizzle, you could synchronize it with the music playing on your radio.

Your description is about 20 years out of production…they used to do exactly that.
But market research, supply and demand -vs- cost, price, and complexity kind of took away the need for infinitely variable wipers.

Market research showed that even WITH the infinitely variable feature, Joe Driver would ultimately chose a long, medium, or quick delay and the rest was basicaly useless.

My 78 Cordoba, 80 Bronco, 91 & 92 Explorers all had it.

I believe some vehicles have a true variable speed wiper system. I drive a lot of different vehicles so I can’t remember exactly which ones had it. I think my Dakota has variable speeds without a detent for each speed. You can also buy variable speed wiper switches for older vehicles with 2 and 3 speed wipers to convert them to variable speed.

My company’s van (GMC full size) and my Camry both have the feature you describe.

There was a neat VW commercial years ago that synchronized the wipers to the music and everything going on in the background–someone can likely find it and post from youtube.

Wipers could be controlled exactly as you describe when they were operated with vacuum motors. They worked until you accelerated and then manifold vacuum was minimal and the wipers would slow or even stop unless your car, like my dad’s late 1950s model had an auxiliary vacuum pump as part of the engine mounted fuel pump. I liked vacuum wipers as they could be run extremely slow when rain was light. I prefer that to an occasional fast wipe. Others apparently think differently.

There is no reason now other than a little added cost to add a speed control to an electric wiper motor even with feedback to maintain constant speed under varying load conditions such as very wet or only a little wet and with varying wiper blade sizes and blade condition.

Go to Radio Shack & I’ll bet someone there can tell you how to rig one.

Both my '97 Ford and '00 GM vehicles have lots of gradations. Its not infinite - 1/2 dozen or more positions each. I never counted, but whatever each has, its plenty.

If you mean, why doesn’t the actual speed of the wiping change, not just the delay, I’d think it’s because it would be a vision hazard to have the wipers languidly moving across, obstructing your view. If you mean an ‘infinite’ number of delay settings, I’ve had several cars with exactly that.

Some cars, including my current one, have rain sensing wipers, so they go when they detect water only. I find this a little distracting and disconcerting (I guess the human mind craves rhythm), so I turn off this feature.

I don’t think anyone at Radio Shack could tell you how to rig anything. I get the ‘deer in the headlights’ look from their clerks when I ask for electronic components there.

I had it that feature on my Dodge Coronet…

The trick was setting it to music you were listening to at the time.

I think Ken Green nailed it. I know I’ve had cars that were infinitly variable in the past but I couldn’t tell you if what I have now is or isn’t. That’s how unimportant it is. Plus the one I remember, developed some soft spots on the slider that was more than irritating.

@oblivion

I have sensing wipers too, though it is in lieu of timed delay settings; I can only adjust the sensitivity of them.
I actually find them quite amusing to watch. How they go from delayed to constant in mere seconds is kinda neat. I had never seen them go high speed until a couple days ago when it was pouring down rain on my way to work.

On my 2005 Camry, I have low, medium and fast. On the low speed, there is a rheostat on the arm that I can turn to increase or decrease the speed. Pretty neat, but don’t use it much, esp this year with only 1" of rain in Southern California.

@bscar

When mine are in sensing mode, the first few clicks adjust the sensitivity and the last few before the continuous settings are delay. The thing that bothers me is how utterly random it seems to be when they ‘pounce’ on the the rain. I find it more distracting than useful. The feature that increases and decreases the delay depending on whether you’re moving or not is nice though. Fortunately you can easily turn off the rain sensing feature from the electronic menu system on the dash display.

From Oblivion Quote" If you mean, why doesn’t the actual speed of the wiping change, not just the delay, I’d think it’s because it would be a vision hazard to have the wipers languidly moving across, obstructing your view." Unquote

I can assure you that I have driven many cars with vacuum wipers and it never occurred to me that vision was a problem with a wiper set at a very wiping slow speed. If it was a problem for some, it would be an easy matter to simply speed up the wipers.

@oblivion

I don’t remember seeing that feature in my owner’s manual. May have another look, but I don’t think I can change it