The Mechanical Handling and Storing of Material

84 THE MECHANICAL HANDLING OF MATERIAL These supporting rollers are 4 to 6 in. in diameter, and are sometimes made of wood, but more often consist of steel tubes to which spindles with conical end gud8eoilJ are secured. These gudgeons generally run in suitable bush bearings, w ic siou be well lubricated. s Fig. 112. Support for Band Conveyor of the Robins Conveying Belt Co. A more elaborate bearing is the one illustrated in Fig. 111. It consists of a neat cast-iron bracket which can be clamped to the angle-iron framework of the band conveyor without necessitating the drilling of holes in the same. The bearing is adjustable up and down, while one end is formed into a Stauffer lubricator, which can be filled with . a viscous lubricant. This bearing being long and movable, will adjust itself to the position of the spindle, so that friction should be reduced to a mini- mum. The appliance is also fitted with a removable cup for the reception of any surplus lubricant. used at intervals in addition to the point oi points ___-• The type most generally in use is that illustrated modification of the same principle for wider belts, shown in Figs. 113, The former was first introduced by the Robins Conveying l>elt Co. Sometimes curving rollers are where the conveyor receives its feed, in Fig. 112, and a 114, 115, and 116. Fig. 114. Seven-Roller Troughing Idler.. about 1885, and is now almost universally used either as illustrated or with slight variations. Theoretically, it cannot be considered correct to use idler pulleys of small diameter for narrow belts, and larger ones for wide belts, as is generally the case. The belt speed should be taken into consideration, and fast-running belts should be fitted with larger, and slow-running ones with smaller, diameter rolls. Conveyors for grain and seed, which almost invariably run faster than those for minerals, generally have the