GB757054A - Improvements in or relating to the driving mechanism for printing machines - Google Patents

Abstract

757,054. Printing machines. GLOCKNER, P., [trading as GLOCKNER, P. [Firm of]]. June 29, 1954 [Aug. 5, 1953], No. 19009/54. Class 100 (2). Driving arrangements.-A printing machine is driven from a constant speed motor through a continuously variable gear, the motor also driving, at constant speed, a pump for supplying vacuum to the suction sheet-feeding apparatus. In the form of Fig. 1, the motor 3 drives the main shaft 1 of the printing machine 2 through a belt 4 passing round an expanding pulley 7 on the motor shaft 5. This pulley consists of two cones keyed to the shaft, one of the cones being slidable along the shaft and spring-loaded towards the other. Another pulley on shaft 5 is connected by a belt 11 to the driving pulley 12 of the pump 13. Both the motor and the pump are mounted on a sliding base 14 movable towards and away from shaft 1. As the motor is moved away the tension of the pulley forces the cones apart, reducing the effective diameter of the pulley and consequently reducing the speed of the machine shaft 1. The base 14 is displaced by cranks 19 connected to a shaft 18, an arm 20, Fig. 2, on the shaft being connected by a pivoted nut 21 to a threaded rod 22 rotated to displace the base by a handle 23 acting through bevel gears 24. A pointer 26 on shaft 18 cooperates with a scale to indicate the speed of rotation of the printing machine. The expanding pulley may alternatively be controlled by the tension of the belt derived from an adjustable jockey pulley running against the belt. In a modification the expanding pulley may be controlled directly, the belt tension being suitably maintained by the jockey pulley.