In this article, we’ll be discussing an Air Valve for Tubeless Pneumatic Tire by CushCore, US patent 10,703,149. The publication date is July 7th, 2020 and the filing date is May 14th, 2018. This patent has been granted as novel by the USPTO.
I want to make this clear; this isn’t a review. I do not own CushCore, nor have I ever used it. CushCore asked me to provide a technical article of the explicit legal design to you because they believe in the product and want you to understand the technical aspects of the design. It’s very cool to see a company not rely on marketers to sell a product because they’re confident enough to ask a third party to provide an unfiltered explanation of it. I honestly did not add or remove anything at their request; I just simplified what they’ve already told the USPTO. I know the bike industry maintains a pretty constant level of skepticism of product reporting. I’m hoping this helps.
Brief Summary (tl;dr)
CushCore have developed a valve to work with their tire inserts. The inserts create a radial pressure on a traditional valve, which blocks the outlet side of the valve. Their solution is to create a valve that directs airflow circumferentially or perpendicular to the inlet flow. The inside most side of the valve is a flat plane, so the insert can sit nicely on the valve without any obstruction. There is also another example that could come in the future, where the inside of the valve is not linear. Instead, it’s curved to allow for a smoother transition of flow to the tire. It’s also important to note that you don’t need the inserts for these valves to work, if you like their pretty colors.
First, let’s define three terms: axial, radial, and circumferential. Axial is the direction through the axle. Radial is the direction perpendicular to the axle rotation, so it’s just up, down, forward, backward, etc. Circumferential is the direction around the tire, so basically just a circle.
CushCore have developed a tubeless tire valve to accompany their tire insert design. In short, the tire insert provides a radial pressure to the inside of the wheel and, therefore, will provide pressure to the outlet-side of a valve, where the air is supposed to come out. So, CushCore have created an insert that also creates another problem of actually filling the tire with air. Any idiot can see this isn’t ideal.
Their answer is this valve, that which directs air circumferentially rather than radially.
The intended novelty of this valve is the fact that the outlet side (inside the tire) is wider than the inlet side, and the flow of air exits the valve through the sidewalls of the outlet side in such a way that the flow of air is not blocked by the insert. I know that sounds strange, but that’s how you have to define novelty from a legal perspective.
FIGs. 1 and 2 show a typical valve design, where the flow of air is directed radially. This is due to the ‘linear bore that runs through the valve shaft from inlet to outlet’.
The issue here is, when using an insert, getting air into the tire without being blocked by the insert itself. They state the intent of this design:
… [the] air valve… has a specially configured air passageway that allows a tire to be inflated and deflated even when the internal end of the valve stem is occluded and blocked, for example, when the internal end of the valve stem is in contact with an internal structure in the tire, such as the [insert]…
FIGs. 3 and 4 show CushCore’s primary design. Notice the air outlet 32 will direct airflow circumferentially rather than radially. As stated before, this is to keep the valve from being plugged up by the insert. Here’s what they say:
It will be appreciated that since the air outlets 32 do not exit the valve through the terminal end 34 of base 18 and instead exit through the side 35 of base 18 it is possible for air to flow through the air passageway 30 in both directions even if an internal structure such as the [insert]… is pressing against terminal end 34.
They also have an example of a second idea that may be produced one day. See component 42 with the dashed lines at the outlet end? That’s the exact same idea as the current system, but with a smoother, less obtrusive, non-linear flow path. From my days in the aero world, I can tell you for certain that this design would, at least, be marginally better for airflow, reducing back pressure to the pump. I can also tell you that it could be significantly more difficult to actually manufacture, which would render the marginal gains useless. However, if they can figure out how to make a non-linear hole more cost-efficient, it’ll be better.
They also open up the design to more or less outlets. It also appears that the currently available product has a radial hole, just like a normal valve. That’s a smart move for airflow to tires without an insert.
It will be appreciated that one air outlet would be sufficient, or more than 2.
Oftentimes, when something brand new is developed, you find you’ve also created additional problems — for example, the dropper post. The idea of the dropper is (now) a no-brainer; it’s one of the most important modern mountain bike innovations. But some of the earlier designs (KS, for example) incorporated a release below the seat, so you had to take your hand off the handlebars to get that thing up and down. I think we can all see the issues with that. Therefore, handlebar-mounted actuation was introduced. Now, we have amazing seat posts with easy-to-use and safer actuation.
Along with numerous other innovations, this valve is a result of the same process. CushCore created their insert and realized they’d made a new problem of trying to fill the tire with air or sealant — so they developed this valve. It’s a simple design with no fluff or pomp. It’s just a solution to a problem that needed to be addressed so the inserts could be more user-friendly.