Samuel Freeman of New York had US patents granted in 1940 and 1949 for daylight-loading developing tanks for roll film. They are clearly of the Rondinax 60 style and I do find it hard to see how the US patent examiners were satisfied as to originality. Here is the first:

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And here is the second, a claimed improvement on the first. Rather than pulling on the backing paper as in the Rondinax, the spool was rotated in order to separate the film.

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The film loading appears to be over-engineered to meet a demand that did not exist. However, the gearing of the spiral is a real improvement other than in terms of elegance or size. Because the turning knob is above the water level, the tank body is not perforated and washers, sealing screws etc are not needed. The tank simply cannot leak.

Whilst I can find no trace of the tank (unimproved or improved versions) having been manufactured, I do find it a little strange that Freeman should seek a patent for his later version if the former had never made it to market. Are there some Freeman tanks somewhere in the USA?