Fifty-year-old Kenneth Williams apologized during his sentencing Tuesday, saying he was suffering from mental health issues at the time of the May 2008 attack.
Prosecutors were seeking a six- to 12-year sentence for the Norristown man, who was convicted in April of attacking cabbie William Millburn after being picked up in North Philadelphia.
Police say Williams threatened Millburn with a knife during a scuffle that ended with Millburn driving off in the cab.
Common Pleas Judge Willis Berry Jr. rejected Williams' insanity defense at trial but said he was sympathetic toward the defendant, who like him had been a cook in the military.
