精选优质文档-倾情为你奉上Passage 1 (原题库第1篇) Valve drive mechanism The valve drive mechanism commands the inlet and exhaust valves at the required timing. 第3题The valve drive mechanism consists of an inlet and exhaust cam follower (8) each suspended in a plunger of the tappet assembly (7), two tubular push rods (4) with ball joints, two nodular cast iron rocker arms (2) suspended in a rocker arm bearing bracket, two yokes (5) and a yoke guide pins. See Fig. 4-1.