t End plate Circlip Dimensions in mm d d d d f l l B4-CV-5-D Bevel-helical gear reducer B4

Flender/Flender Gear Units/Bevel-helical gear reducer B4

the machine, the coffee is squeezed between the ribs and the knife; the shells shatter and separate from the beans. Types offrictional hullers are smout-type hullers, roll hullers, crossbar hullers, and compact hullers.The important smout-type hullers consist of rotor with helical pitch that increasestoward the discharge end. The rotor turns inside horizontal casing comprising two match- ing concave halves with spiral grooves. The spirals on the rotor turn in the opposite direc- tion from those on the casing. The ow of coffee is controlled by balanced gate at theexit, which can be set to increase or reduce the ow out of the huller, thereby regulatingthe pressure buildup inside the casing. Impact hullers rely on impact rather than friction. The advantage is that virtually no heat is generated and less power is used than in the traditional hullers. Most impact hullers cannot handle cherry coffee and are mainly used for parchment coffee. The impact huller consists of horizontal disk spinning rapidly on vertical axle inside circularchamber. The edge of the disk is ringed by hardened steel pins or round bars. Coffee is fed onto the center of the spinning disk and is thrown out toward the ring steel pins by centrifugal force. The parchment hulls shatter when they hit the steel pins, leaving thebeans free. Hulls and beans are separated pneumatically. The disc speed can be adjusted to suit the degree of brittleness of the product. 3.6 Polishing, Grading, and Sorting Green coffee beans undergo further processing, such as polishing, grading, and sorting. 3.6.1 Polishing Polishing involves removal of the silver skin except that retained in the center cut of the beans. The purpose is purely cosmetic, to improve the appearance of the bean. Polishingmay not be required for wet processed coffee. . robusta has tough and tenacious silver skin, which requires wet polishing operation to remove it. Polishers (.., the Okrassahuller-polisher; see Fig. resemble these of smout