The cargo space of any car, truck, or SUV is limited by the legally mandated spare tire, because getting stuck on the side of the road for an indefinite period of time is dangerous for everyone in the vicinity. The problem is that, even though full-size spares are becoming rarer, there’s never enough space in a new car. So Ford has filed a patent with the German Patent and Trademark office for a self-inflating tire that only activates when necessary. There’s more to it than that, though.
How It Works
The Blue Oval’s patent describes taking advantage of an existing on-board compressor to inflate the spare tire beneath the vehicle’s rear bumper when a computer, using wireless short-range signals, determines that one of the operating tires (those on the hubs of the vehicle) loses pressure. If this happens, the spare tire instantly inflates, ready for a quick change. But if, for example, the driver happens to notice the puncture (or only do something about it) once they get to a service station, and the damaged tire returns to a state of high pressure, the system would automatically deflate the spare.
Why It Matters
The idea is not to create space for storage, because a self-inflating tyre would use that space once activated anyway. Rather, the idea is that a deflated tire “can reduce a stack-up of components” in certain impact scenarios. This is all about safety and preventing cabin ingress of impacted vehicle components, and although other similar ideas have been explored in the past, this one’s specific configuration could enable it to pass safety standards.
However, it must be noted that if the spare tire’s compressor is originally intended for some other purpose, the small tank attached thereto may have been recently deflated. For example, a driver leaving the worksite may have just been using the compressor for a power tool, or a naturist may have just reinflated their bicycle tire after a puncture in the woods. In such scenarios, the tank of compressed air would not be full and would therefore be unable to instantly inflate. While Ford recognises this as a potential safety risk, as the tank is small it should refill by the time the driver returns to a reasonable driving speed.
