Tham khảo tài liệu 'mechanism of steam engines part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | IÓ4 MECHANISM OF STEAM ENGINES the piston N through the passage At and when on account of increased load the mean position of the relay plunger p is raised sufficiently by the governor the port o is opened exhausting the steam from the upper side of the piston N and the valve is raised by the pressure beneath N. Gov Ball Gov. Rock Gov. Case Gov. Gov. Bevel Pinion Spring Gov. Bevttl Vibrator Cam Worm Wheel Shaft . Wjrm Gov. sptnđiữ Gov. Trigger Vibrator Rod . Gear Case Vibrator Roller Fig. 183. Gov. Lever Link . Knife Edge Pin and Block T Arm Roller and Pin Connecting Link Dash Pot Lever Dash Pot Clutch Clutch Vibrator Rod Lint Clutch Lever Pump Crank . Worm Wheel The port o may be permanently closed by the hand valve Ọ thus cutting the secondary valve entirely out of action. Fig. 183 shows the governor mechanism as far as the shaft T which carries the motion to the relay plungers through suitable levers and links. The governor clutch lever F has its fulcrum on a collar or governor clutch which can slide on the governor sDĨndle. F is rocked about its fulcrum by the governor vibrator cam ink Í her end of F rocks the shaft T by means of the ST diort TURBINE VALVE MECHANISMS AND GOVERNORS 165 link. The governor spindle z is driven from the main shaft of the rotor by the governor worm worm wheel A and a paừ of bevel gears. As the speed increases the weights w swing out and raise the collar which forms the fulcrum of F. The arrangement of the levers between T and the relay plunger is such that as the fulcrum of F is raised the relay plunger is lowered. Since F rocks approximately the same amount about its fulcrum for all positions of the governor the shifting of the fulcrum of F merely changes the mean position of the relay plunger without materially changing the length of its stroke. This change of mean position varies the steam supply as already .