| 摘要 |
The braking system includes mechanically actuated apparatus to move the brake shoes into frictional engagement with the locomotive wheels. The mechanically actuated apparatus has a hand wheel suitably mounted in the operator's compartment. The hand wheel is connected to one end of a rotatable screw device. The other end of the rotatable screw device is threadedly secured in a threaded bore of a bracket member. The bracket member is secured to a transversely extending equalizer bar. The equalizer bar is connected by a pair of link members to vertically extending brake levers through a lost motion connection. The vertically extending brake levers are pivotally secured to wheel brake assemblies that include a pair of depending hanger levers to which brake shoes are pivotally connected. The brake assembly includes a wear adjustment device to adjust the position of the brake shoes due to wear. Rotation of the hand wheel moves the bracket and equalizer bar longitudinally and through the link members pivots the vertically extending brake levers. The brake levers, in turn, move the brake shoes into frictional engagement with the wheels of the locomotive and apply a braking force thereto. The fluid actuated auxiliary braking apparatus includes a manually operated hydraulic pump in the operator's compartment connected to a source of hydraulic fluid. The actuating shaft of the pump has a hand wheel connected thereto. One or more piston cylinder servomechanisms are mounted on the locomotive adjacent the equalizer bar with the piston rod connected thereto through suitable overtravel linkages. The ports of the hydraulic pumps are connected by conduits to the cylinder on opposite sides of the piston within the cylinder. Rotation of the hand wheel connected to the hydraulic pump in one direction supplies fluid to the piston cylinder assembly to extend the piston rod and move the equlizer bar. Movement of the equalizer bar moves the brake shoes into frictional engagement with the locomotive wheels through the same linkages associated with the mechanically actuated apparatus. The rotation of the hand wheel connected to the pump in the opposite direction moves the brake shoes out of frictional engagement with the locomotive wheels. The amount of frictional force exerted by the brake shoes when actuated by the fluid actuated auxiliary braking system may be easily, accurately and positively controlled.
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