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bearings exert an outward radial force on the cups
I understand that point and I am still thinking about it. But, if deformation exerted by the bearings on the cups would be a problem, then even with normal cups in a standard 1" setup for example, the bracing support by the headtube would never be sufficient to prevent a gradual deformation of the cup by the bearings over time, because the headtube is sitting quite a few mm below, not in the same "plane" as the cup itself).
But, apparently reality shows that this is not happening?One more thing to consider: the bearings itself in my concept are IS41 industry bearings, which usually have a closed stainless steel body. Unlike an open BB ring like it is used in 1" headsets, these bearings offer a certain structural integrity in themselves, helping to distribute any forces coming from the steerer much more evenly onto the cup
jetski-
the bracing support by the headtube would never be sufficient to prevent a gradual deformation of the cup by the bearings over time, because the headtube is sitting quite a few mm below, not in the same "plane" as the cup itself).
I'm not sure about that. The effect of the force over the whole cup would be to expand it slightly. With a normal cup that would tighten the cup against the inside of the headtube. In your design it loosens it from the headtube, which could lead to fretting
If the force is not consistent around the cup i.e., it's acting to push just one point of the cup outwards then, in a normal cup, that force is dealt with locally by the cup pushing against the inside of the headtube at that point. In your design that force acts against the outside of the headtube on the opposite side, which stretches the cup overall.
I don't think it's a bad solution, it had occurred to me that you could do this. I just think there's a reason that previous versions have actually been brazed or bonded to the headtube.
ffm
If I understand it correctly the problem is that the bearings exert an outward radial force on the cups (and a corresponding inward force on the steerer) in addition to the axial force. In a normal headset the cups are braced against that radial force by the headtube, but in your design they're not. Instead you're relying on the strength of the cup itself to resist any non-axial forces that might deform it. If the cup does deform then it might unseat slightly from the headtube and, even if it can't walk off it, it might fret and wear both itself and the headtube.
I assume that's why previous efforts at this have actually brazed or bonded the cups to the headtube.