that article seems to be mainly about the accordian, with, I might add, some unverified claims (ie no sources cited). it does however state, which I have seen cited elsewhere, that

The concertina, patented in two forms (perhaps independently): one by Carl Friedrich Uhlig, 1834 and the other by Sir Charles Wheatstone, of which examples were built after 1829, but no patent taken out until 1844.

Charlotte R