Stationary steam engines, simple and compound; especially as adapted to light and power plants . d and thus by changing its lead, to determine themovement of the cut-off valve and the ratio of expansion. There is nothing specially remarkable about this part ofthe arrangement. The position of the weights is seen to bedetermined, however, by a system of bell-crank levers whichconnect the middle point of each weight with a vertical rodand chain under the engine bed, and on this rod is carrieda set of weights which may be easily reached when the ELECTRIC LIGHTING PLANTS. 93 •engine is running. The
Stationary steam engines, simple and compound; especially as adapted to light and power plants . d and thus by changing its lead, to determine themovement of the cut-off valve and the ratio of expansion. There is nothing specially remarkable about this part ofthe arrangement. The position of the weights is seen to bedetermined, however, by a system of bell-crank levers whichconnect the middle point of each weight with a vertical rodand chain under the engine bed, and on this rod is carrieda set of weights which may be easily reached when the ELECTRIC LIGHTING PLANTS. 93 •engine is running. The bell-cranks within the governor•casing, move a rod which passes along the centre line ofthe governor shaft and emerges at the left. This rod en-gages a large bell-crank at the end of the shaft, throughwhich the load suspended under the engine is o;ie spring, and that a small one, is seen in the wholesystem. The centrifugal action of the governor weights,when at the inner limit of their range, is met by the weights•on the scale pan, and the spring is only required to meet. The Cummer Governor. the additional action of the governor weights when theyfly outward, as the engine increases speed. The more nearlyan equilibrium is maintained between the action of theflying weights and the balancing load, at the proper speedof engine and at all possible positions of the governor, themore perfectly isochronous does the governor become,and the more exactly will the engine hold its speed, underall variations of steam pressure and of load. With this 94 STEAM EXGINES FOA governor, the weights on the pan can be increased ordiminished at any moment, and to any desired amount,whether the engine is in motion or at rest; the isochronousadjustment can be effected as nearly as desired, and thespeed of engine may, at any moment be altered, much or littleas may be advisable. This accessibility of the governor, and the disuse ofheavy springs to control it, are the principal advanta
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectsteamen, bookyear1902
