THE TRACTION GEARING. 



97 



(Fig. 30), press lightly against the rim of the fly-wheel, 

 transmitting only part of its motion to the gearing. But when 

 in full engagement, the shoes press so hard against the rim of 

 the fly-wheel that they prevent slipping, thus locking the fly- 

 wheel and pinion, (C), together. The two shoes are hinged 

 to the ends of the arm, (B). This arm has a long sleeve, 

 which is loose upon the shaft, but at the end of which the 

 pinion, (C), is firmly keyed. The sliding ring, (D), (Fig. 

 31), is loose upon the sleeve, and when moved toward the fly- 

 wheel, straightens the toggle levers, thus pressing the shoes 



against the rim of the fly- 

 wheel. The sliding ring is 

 moved by means of the trun- 

 nion ring, (E), which re- 

 mains stationary, but allows 

 the sliding ring to revolve 

 within it. The trunnion ring 

 is held to the sliding ring 

 by means of the clamp ring, 

 (F). 



Adjusting the Clutch. 

 The wear on the shoes is 

 taken up by means of the 

 turn-buckles in the toggle levers. They should be so ad- 

 justed that the toggle levers will just pass the straight line 

 when the clutch is in engagement, thus relieving the trunnion 

 ring of all side friction; they should also be so adjusted as 



FIG. 31. FRICTION CLUTCH. 



