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ACORN 80 Maintenance & Service Manual
SECTION 2
Description Of Operation
2.2 Carriage Operation
The carriage comprises a power bogie (PB) and a levelling bogie (LB) mounted on a common frame (F). The
carriage is held square on the rail by side rollers (S) on both power and levelling bogies.
The downward weight of the power bogie is taken on the support wheel (SW) running on the bottom of rail (R).
The support wheel may bear against underside of the rail when negotiating vertical bends.
The downward weight of the levelling bogie is taken on the top roller (TR) running on the rail (R).
The drive motor (DM) rotates a pinion (P) on a rack to drive the carriage along the rail.
The levelling motor (LM) adjusts the frame to maintain the seat upright when moving over vertical bends.
An over-speed governor (OSG) will activate and stop the carriage in the case of an uncontrolled descent.