From NKAA, Notable Kentucky African Americans Database (main entry)
Baker, David
(born: 1881 - died: 1959) Said to have been born in Louisville, KY, David Baker, the son of John B. Baker and husband of Celena Le'Cleac, invented scales that were used in elevators to prevent overloading. He was in charge of the elevator in the Board of Trade Building in New Orleans, LA, for 10 years. He left New Orleans and moved to Los Angeles, CA in 1910.He was also co-inventor of the streetcar transom opener in 1913, the high water indicator for bridges in 1915, and a number of other inventions.
Baker seems to have given a number of birth locations; in 1900, when he was boarding with the Vinet Clarisse family in Louisiana, he gave his and his parents' birth locations as Louisiana and his birth date as February 1881. He is listed in the census record as a mulatto. In the 1920 Census, he and his wife and child are listed as white, and their birth locations are given as France; the family may have been passing or the census taker got the information wrong. In the 1930 Census, both he and his wife's birth locations are listed as Alabama, and they are listed as Negroes. In the 1940 Census, David Baker and his wife's birth location are given as Louisiana, and both are listed as Negroes. David Baker was listed in the 1937 city directory when he was employed as a janitor at the State Agriculture Association [source: p. 172 in the Los Angeles City Directory, 1937]. On his World War II draft registration card, David Baker gave New Orleans, LA as his birth location, and his birth date as April 2, 1884. On his World War I draft registration card, Baker had given his birth date as April 2, 1879 with no birth location listed; he was a janitor at the Union League Building in Los Angeles.
David Baker died in Los Angeles, California on March 20, 1959; his birth date is listed as April 2, 1888, and his birth location is given as Louisiana [source: California Death Index].
For more see Who's Who of the Colored Race, 1915; and The Pride of African American History: inventors, scientists, physicians, engineers..., by D. Wilson and J. Wilson.