Robert Sinclair, an automobile executive whose brainchild, the Saab 900 convertible, turned Saab into a prestigious brand in the American market, died May 10 in Santa Barbara, Calif., where he had lived since shortly after his retirement in 1991. He was 77.

Sinclair, who had been a salesman and midlevel executive at Saab, the Swedish automaker, in the late 1950s and early 1960s, rejoined the company in 1979 as president of its American division, then known as Saab-Scania.

Saab’s American sales increased from 13,513 in 1980 to 39,264 in 1985. But Sinclair’s greatest triumph was ahead. Having been pressed by corporate headquarters in the early 1980s to accept an annual shipment from Sweden of 1,000 two-door economy-model sedans for sale in the United States, Sinclair balked and cut another deal. He would accept the cars only with higher-end specifications, including convertible tops.

At the time, American car companies had largely stopped building convertibles, fearful of rumors that the government would outlaw them as unsafe. The regulations never came, and the Saab 900 convertible became a sensation.