GB819328A - Improvements in or relating to belt sanding machines - Google Patents

Abstract

819,328. Abrasive belt machines. CARBORUNDUM CO. Feb. 13, 1957, No. 4887/57. Class 60. A belt-sanding machine comprises a serrated endless back-up belt positioned to travel around a pair of pulleys 5, 8 mounted on a base, means for driving one of the pulleys, an endless abrasive belt positioned to travel about one (5) of the pair of pulleys and a third pulley 9 also mounted on the base, means for independently moving one of the pair of pulleys and the third pulley in a plane through their axes to adjust the tension in the back-up and abrasive belts respectively, means for independently tilting the axes of one of the pair of pulleys and the third pulley to control the tracking of the back-up and abrasive belts respectively, and work-tables 16 attached to the base and positioned opposite each other along the two stretches of belt travel between the pulleys. The back-up belt, which preferably consists of a backing of cloth cemented to a rubber layer formed with parallel depressions on its outer face, travels over the pulleys 5, 8 and platens 51, 52 mounted on the base 1. The pulley 5 is driven by an electric motor 4, and the pulley 8 is mounted in a bracket 23 pivotted by a pin 25 to a member 24 slidable along longitudinal guideways on the base 1. The bracket is rocked about the pin to control the tracking of the back-up belt by a screw 28 co-operating with a nut 27 and locked in position by a screw 29, and a handwheel 32 and screw 30 are provided to tension the belt by sliding the member 24 along the base 1. The pulley 9 is located in the same plane as the axes of the other pulleys and is mounted on bearings on a spindle removably carried in a bush on a carriage 36. The carriage may be moved by means of a screw 34 and handwheel 35 to adjust the tension of the abrasive belt, which fits over the pulley 9 and the back-up belt, and a screw 37 tilts the axis of the pulley to control the tracking of the belt. The worktables 16, one or both of which may be vertically adjusted by means of a screw 11, are provided at each side of the belts between the pulleys 5, 8; pins 14 co-operate with bushes 15 to guide the vertical movement of the table. The vertical movement provides means for ensuring even wear of the abrasive belt. One or both of the tables may be angularly adjusted about edges 21, Fig. 3, by means of an arcuate slot 18 in a member 17 co-operating with a roller-pin 19 and a handscrew 20 which provide guiding and locking means. A third table 39, Fig. 2, may be provided to permit sanding at the pulley 9 and may be fixed as vertically and/or angularly adjustable by means similar to the worktables 16.