PRINCIPLES OF NAVAL ENGINEERING 



DISK CLUTCH-7 /-BEARING CAGE 



TOGGLE ASSEMBLY. 



CONE CLUTCH 



■FRONT COVER 



COLLAR AND 

 YOKE 



REDUCTION 

 GEAR SHAFT 



PROPELLER 

 DRIVE SLEEVE 



ENGINE SHAFT 



ENGINE SLEEVE 



PINION GEAR (LONG) 



PINION GEAR (SHORT) 



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Figure 22-37.— Cutaway view of Joe's clutch and reverse gear. 



propeller drive sleeve. In addition, tiie force of 

 the plungers on the disk clutch is transmitted 

 to the bearing cage, which is a cylinder con- 

 taining the reverse gear pinions. The bearing 

 cage, in turn, is pressed against the cone clutch. 

 Thus, the cone clutch is forced against its seat 

 in the front cover of the gear box, clamping the 

 clutch to the front cover by friction. Since the 

 cone clutch is in mesh on its inner surface with 

 the engine sleeve, which is in turn keyed to the 

 engine shaft, the front cover is now locked to 

 the engine shaft. The front cover must rotate 

 with the engine shaft, in the same direction. 



Now, since the front cover is bolted to the 

 drum housing, which is locked to the propeller 

 drive sleeve by the disk clutch, there is a com- 

 plete lock from the engine shaft to the reduc- 

 tion gear shaft. The entire assembly rotates 

 as a unit in the same direction as the engine 

 shaft; this motion gives the propeller a forward 

 rotation. 



When the operating lever is thrown into the 

 reverse position, the plungers are withdrawn. 



and both clutches are disengaged. At the 

 same time the brake band is tightened around 

 the drum, holding the drum stationary. The 

 bearing cage is locked to the drum. The cone 

 clutch rotates freely out of contact with the front 

 cover. Then the motion from the engine shaft to 

 the reduction gear shaft is transmitted through 

 the inner gear assembly. 



The reverse gear pinions are held in the 

 bearing cage, which is stationary for reverse 

 rotation. There are three short pinions, each 

 in mesh with the small inner gear of the engine 

 sleeve. The three short pinions mesh with the 

 three long pinions, each of which also meshes 

 with the propeller drive sleeve gear. Engine 

 rotation is transmitted from the engine sleeve 

 to the short pinions, to the long pinions, and to 

 the propeller drive sleeve. These pinions (gear 

 train) cause the reduction gear shaft to rotate 

 opposite to the engine rotation (see arrows in 

 fig. 22-37), and give the propeller a reverse 

 rotation. 



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