HORSE-POWERS 135 



for the twenty-bar or 1075 for the twelve-bar cylinder of 

 "Case" separators fitted with a side-gear, requires a tumb- 

 ling-rod speed of about 227 revolutions per minute. The 

 required speed of the tumbling-rods is found, in each case, 

 by multiplying the number of revolutions of the cylinder 

 by the number of teeth on the cylinder-pinion and dividing 

 the product by the number of teeth on the bevel-gear. For 

 cylinder speed of 300 with the 2O-bar separator for Beans, 

 use Bevel Gear 5O7iT (47 teeth) and Pinion A5O72T (25 

 teeth) and Spur Pinion A8W on horse-power. 



Jacks for Horse-Powers. Ordinarily, a separator in- 

 tended to be driven by a horse-power is fitted with a side- 

 gear. However, sometimes a belt machine is driven by 

 a horse-power, and for this purpose a device is used to 

 change the motion of the tumbling-rods into that of a pul- 

 ley from which the separator cylinder may be driven by 

 means of a belt. This device is called a "jack." When a 

 "jack" is used to drive a belt machine, 40 feet of drive 

 belt will be needed for 12 bar and 60 feet for a 20 bar 

 machine, to insure clearing "ironsides." The "Case" jack 

 has a bevel-gear (2o8T) with sixty teeth and a pinion 

 (200/T) with twenty-two 'teeth. The pulley (2o6T) is 

 sixteen inches in diameter and has a six-inch face. 



Adjusting the Iron-Frame Horse-Power. It is very 

 important that the bull-pinions should mesh properly with 

 the bull- wheel. When the bull-pinion shafts are correctly 

 set, the bull-wheel will not have more than one-sixteenth 



