NEWBURYPORT – A Beverly machinist involved in a two-car accident in Lynn was convicted Wednesday of driving drunk for his fifth time and received up to four years in state prison.Gary R. Duvall, 46, of 457 Rantoul St., Beverly, went on trial in Newburyport Superior Court earlier this week.Jurors found him guilty Wednesday morning of driving a motor vehicle while under the influence of intoxicating liquor in connection with an accident in Lynn in January.Judge Richard E. Welch, III, then found him guilty of the previous four other convictions dating back to 1980.He sentenced Duvall to serve not less then three years and not more than four years in state prison.Assistant District Attorney Kim M. Faitella presented evidence that on Jan. 2, Duvall was involved in a two-car accident in Lynn on Linwood Road when he crossed the lane and struck another vehicle.Authorities retrieved two plastic cups at the scene, one contained beer.Police responding to the scene said Duvall was swaying back and forth at times, his eyes were dilated and glassy and he failed several sobriety tests.Duvall insisted his left leg was problematic and at times he was unsteady and could not walk on it.Duvall has been held without bail at the Middleton Jail since his arraignment after a judge determined he was a danger to the public.