GB191120957A - Improvements relating to Sand-papering, Emery-grinding and Analogous Machines. - Google Patents

Abstract

20,957. Jarvis, D. J. Sept. 22. Band apparatus. - In a band sand-papering machine of the vertical-drum type having means for vertically reciprocating the abrasive band D, work rests or supports are provided adjacent to the drums E, F. The band D is driven by the drum E, which is carried by a spindle G mounted in bearings H<1> on a framing H supported on spring-controlled plungers C. The spindle G engages by means of a feather the boss of a pulley H<2> driven from a pulley H<6> on a countershaft J. The drum F is mounted in a bracket K, which is connected to an extension H<7> on the framing H, the position of the bracket being adjusted in order to regulate the tension of the band D by means of a plunger L, which is operated by a handle L' and clamped in position by a locking- handle L<2>. The table N adjacent to the drum F can be canted above or below the horizontal plane by means of a slotted link R, pivoted to the underside of the table and links P fulcrumed on a shaft N<1> mounted in a bracket N<2> fixed to the bed B of the machine. The table is locked in the desired position by means of a locking-handle S engaging the link R and a locking-screw T engaging the shaft N<1>. A. table O fitted to the flat surface of the band is provided with similar adjusting-means and may be fitted with an adjustable swivel fence O<1> and with a backing-plate O<3> placed behind the band D. The table M adjacent to the driving-drum E may be provided with similar adjusting- means, and either of the tables M, N may be fitted with the work-guides or supports described in Specification 12,712/09. The vertical reciprocation of the band is effected by links U pivoted to bosses H<10> on the framing H, the links U being connected by rods U' to links U<2> pivoted to links U<3> at each end of a shaft V mounted in bearings U<4> on the bed B. The shaft V is driven by a bevel-wheel V', which engages a pinion V<2> on a shaft V<3> driven from a pulley on the countershaft J. In a modification of the vertical reciprocating mechanism, the plungers C supporting the framing H are raised and lowered through the medium of links pivoted to a connecting-rod, which is pivoted eccentrically to a disk driven from the countershaft. The spindle G may be surmounted by a bobbin faced with abrasive material.