William Powers, a team member of a new start-up group called PumpTire LLC, informed me a few days ago of their self inflating tire idea. James of Bicycle Design had posted on his blog that he received the same email as well so I figure that this made the rounds to many bloggers in a mass email.
The idea appears to be the brainchild of Benjamin Krempel. The internet describes him as a CEO of Aqueduct Medical, a company that develops “safe, effective, user-friendly products that improve patient recovery from facial and cosmetic surgical procedures.”
In the video below, he describes the idea (although somewhat vaguely) :
So its basically a pump that operates every time its squished by rolling motion. “The tire is a 26” x 1.5” tire with a set pressure valve”, says the product website. Reportedly, the tire inflates from zero guage pressure. “The pumping mechanism will pump from a flat up to 65psi.”
In a blog entry back in 2008, I listed some “new” cycling ideas that would be serve as cool thought experiments, without exploring any technical or economic aspects. An “on the go tire inflation/deflation system” was first on my list and it had an almost science fiction aspect to it – the idea that the tire would have a feedback system to it to monitor pressure while riding and adjust itself after sampling pressure.
One application where this would be attractive is in public bicycles used for bike share programs where a self inflating mechanism could possibly add to some convenience. It avoids the necessity of adding an extra infrastructure for pumping air by the sidewalk or the need for individuals to carry pumps. For utility cyclists, terms like “rolling resistance” or “wheel inertia” are usually unimportant. Most just want to get from point A to B.
Having said that, a safety feature in the system is a must. The tire shouldn’t injest water along with air. It also shouldn’t over-pressurize and lead to tire bursts. Things like that. In the end, an interesting thought experiment ends up consuming time being developed, tested, re-tested, re-designed, at the same time needing to raise funds for the development and meeting the demands of consumer standards and regulations. By the end of it all, the inventor will want to go for a serious ride to breathe some air.
The idea of a self-inflating tire doesn’t appear to have sprung up now. A few others tried to do something on similar lines, one of them if I remember correctly was an entry for the Specialized : Innovate-or-die” contest that happened a few years ago.
Here’s Sean Conley back in 2007 :
And here’s Kevin Manning, also in 2007 :
Both appear to charge air into the tire through pedaling. A bunch of patents on “self-inflating” tires for cars and bicycles date back to 1800′s. Those can be found by a Google Patent search. That’s what happens when you give people too much leisure time.
Whether Krempel actually first came up with the idea or not is not the issue. The big picture as I see is perhaps that of the slow march of the bicycle towards fulfilling an intelligent, self correcting system. Automobiles, ships and airplanes are already there but the “control architectures” in these complex systems are the by-product of externally driven factors – federal laws or economic incentives. Will the bicycle really benefit from that kind of intelligence? Sounds like a philosophical question.