FEEDING THE SEPARATOR 231 



more (or dry) straw and unscrewing 1 it for less (or 

 damp) straw. See that the trip pins be not allowed to 

 wear rounding- on the points so that they fail to catch 

 each other easily. If worn rounding, they should be 

 reversed end for end or else filed or ground sharp. Do 

 not allow the sprocket chain, which drives carrier and 

 hopper bottom, to become slack, as the proper action of 

 the parts will be interfered with and excessive wear and 

 pounding result. 



Speed of Feeder. With the regular cylinder speed of 

 750 revolutions for the 20 bar and 1075 revolutions of 

 the 12 bar cylinders the knife-arm crank of the feeder 

 will make 258 revolutions per minute. The retarders 

 are driven from the hopper-bottom shaft, either through 

 the intermediate retarder sprocket or direct. The inter- 

 mediate sprocket being reversible, three speeds for the 

 retarders may be obtained for each speed of the carrier. 

 The low speed is best suited for very tough grain and the 

 high speed, when it is dry and fluffy. Ordinarily, the 

 best results are obtained by running the crossed drive belt 

 on the inner set of pulleys. The velocity of the carrier- 

 rake may be increased by using special sprocket A5447T 

 (8 teeth) in place of the regular one, 5447T (7 teeth) on 

 the stud-shaft. 



