Chapter 21. -OTHER AUXILIARY EQUIPMENT 



SPEED 



CONTROL 



BOX 



ELECTRIC 

 BRAKE 



80.149 



Figure 21-8.— A-C electric motor drive winch. 



provided with a shifter yoke which is operated 

 by a lever (7) located near the reverse valve 

 (9). When this lever is moved to the left, the 

 position shown in part A of figure 21-10, the 

 pinion which is integral with it is engaged with 

 the gear (2) on the intermediate shaft. This is 

 the "compound gear" position and gives a slower 

 drum speed with an increase in available line 

 pull. When the shifter lever (7) is moved to the 

 right, the driving sleeve is shifted to the right. 

 This disengages the pinion from the inter- 

 mediate shaft gear (2) and engages the square jaw 

 clutch (13) and pinion which is always in mesh 

 with the main drive gear. This gives a direct 

 drive from the crankshaft to the main shaft, and 

 is called the "single gear" position. The "single 

 gear" gives a higher-drum speed for a given 



engine speed, but with a decrease in the avail- 

 able line pull. 



The speed and direction of rotation of the 

 engine is controlled by a hand lever (14). With 

 the winch in compound gear, the drum turns to 

 lift a load when the hand lever is raised. With 

 the lever in this position, a spool type valve 

 passes steam from the reverse valve (9) through 

 the two top horizontal pipe lines (5) to the 

 cylinders where it drives the engine. The two 

 lower pipes (4) are exhaust lines. When the lever 

 is lowered below the horizontal position, the 

 direction of steam flow is reversed and the 

 engine turns in the opposite direction, thus 

 lowering the load. On some winches, the hand 

 lever is provided with an automatic latch for 

 holding it in the horizontal, or neutral position. 



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