Brake for crankshaft with high moment of inertia - uses counter to compare actual and demand positions of crankshaft to operate brake valve

摘要

A crankshaft is driven by a motor through a clutch brake assembly, controlled through an electropneumatic valve. The valve is controlled by an end of travel circuit which ensures that the crankshaft stops at the TDC position. A second control for the valve is an emergency cutout assembly which applies the brake to the crankshaft. A disc on the end of the crankshaft has radial transparent sectors to signal to the nearest degree using a photocell assembly. This drives a counter controlling a relay on its contacts in the valve supply circuit. The relay is operated when the counter has counted a number of pulses which are equal to a prerecorded number in a memory. The number of pulses counted is indicated on a display. A dynamic amplifier maintains the relay circuit closed until the crankshaft rotation slows down in the braking process.