324 



AGRICULTURAL ENGINEERING 



ropes running over grooved pulleys or sheaves may be used 

 to good advantage. Cotton or Manilla ropes are used 



for this purpose. These 

 grooves are arranged so 

 as to cause the rope to 

 wedge in, thus increasing 

 the effect of friction. 



Wire Rope or Cable 

 Transmission. Where 

 power is to be transmitted 

 some distance, as from 

 one building to another, 

 wire cables can be used to 

 good advantage. The pul- 

 ley grooves should not 

 wedge the wire rope, but 

 instead should have a rub- 



, f,,, , . , , 



Der tiller On Which the 



rope bears. 



Triangles or Quadrants. The power from a windmill may 

 be transmitted to a distant pump 

 by the use of triangles or quad- 

 rants, as shown in Fig. 206. If 

 the wires are long they are sus- 

 pended on rocker arms. 



Gearing. A very common 

 method of transmitting power in 

 agricultural machinery is by means 



Fig. 206. Triangles or quad- 



Of gearing. The Construction Of rants used in transmitting 

 ,, ,, . - - , Power to a pump. 



the teeth is a matter of careful 



design, since they must be made to run smoothly together. 

 In cast gears the teeth are cast to shape, while in cut gears 

 they are machine made. Cut gears are generally more per- 



Fig. 205. An example of the trans- 

 mission of power by ropes and shafting. 



