THE EXTRACTION OF THE JUICE BY MILLS 



207 



In the earlier designs the bar was supported on windows or apertures 

 cast in the housings. The ends of the bar were made with a rectangular 

 section, and the vertical and horizontal adjustment necessary was effected 

 by inserting shims or packing strips. In order that the bar might be with- 

 drawn laterally, the window was made deep enough to accommodate the bar 

 at its maximum depth, distance pieces being inserted in, and secured by 

 bolts to, the housing. 



In most mills of recent construction the rocking trash bar is adopted. 

 This form is indicated in Figs. 109 and no. The lower surface, a, of the bar 

 is shaped to receive a shaft or axle, b, to which it is secured by means of a 

 U-clamp, c. The ends of the shaft are carried in counterpart recesses 

 arranged in movable blocks carried on chairs or stools cast on or secured 

 to the inside of the housing. The horizontal movement of the bar is sub- 



FIG. 109 



stituted by an approximately horizontal movement obtained by the rotation 

 of the bar about the shaft, b ; motion is obtained by the threaded rod, e, 

 passing through the lug, /, cast on the side cap of the mill. Vertical adjust- 

 ment may be made by means of shims, or more effectively by the use of the 

 sliding wedge blocks shown at d in Fig. no. With the exception of the 

 rocking combination all these devices are contained in Watson's patent 

 (1606 of 1871), which has determined the type most commonly used. 



Another method of adjustment very largely employed is included in 

 Fisher's patent (U.S. 738629, 1899). As shown 'in Fig. in, the rec- 

 tangular ends of the bar are supported on rest blocks in windows in the 

 housing. An upper rest block is formed with a journal, a, which receives 

 the upper end of a lever, b, which also engages with projections, c, on the 

 end of the bar. Horizontal screwed rods, d, attached to the end of the lever 

 co-act with ears, e, cast on the housing, whence by means of nuts the lever 

 is moved, and a horizontal movement of the bar ensues. The opening in 



