Stephen Stepanian (February 28, 1882 – October 1964) (Armenian: Ստեփան Ստեփանեան) was an Armenian American inventor and owner of numerous patents including the Elevator and Conveyor, Compound Tool, and the Wrench. He is also accredited as the inventor of a self-discharging motorized transit mixer that was the predecessor of the concrete mixer truck. Stepanian is often called the “father of the ready-mix concrete industry.”
Stephen invented a self-discharging motorized transit mixer that was the predecessor of the concrete mixer truck and applied for a patent in 1916. However, the patent was rejected in April 1917 by the patent office because it was believed that a truck could not support the weight of a concrete mixer on top of it. The patent office also noted that there was no previous patenting information that proves integration was possible with both the mixer and the design of the truck. Other sources suggest that the patent was rejected because Stepanian was not an American citizen. However, on December 21, 1928, Stepanian reapplied for the patent and received approval on November 21, 1933.
