It is clearly one of the few surviving examples of the ill-fated Sears combo lawn-mower / carpet vacuum that was the rage for a couple of years, starting in 1929 and ending production in 1931 or '32. Wikipedia has about two pages devoted to this unique (some would say bizarre) brain-storm of Dr. Rubious Goldberg.
I have only seen three of these iconic inventions in person. One was in a bar in Dead Water, Arkansas; one was in a bar in Two Bits, Arizona; and the third was in a bar in Blind Drunk, Montana.