GB769359A - Improvements in or relating to presses - Google Patents

Abstract

769,359. Operating mechanical presses. SCHULER AKT.-GES., L. March 1, 1955 [March 19, 1954], No. 6067/55. Class 87(2). The power unit for driving the ram of a press is coupled through a flywheel to a change speed gear providing at least one fast speed for the idling stroke and one slow speed for the working stroke of the press ram, the driven shaft of the change speed gear being connectable to the final drive for the press ram through a clutch or clutches controlled by means operable to select the required speed for the press ram operation. As shown in Fig. 1 the two cranks 27, 28 of a double press are driven through gearing including a wheel 19 which meshes with the wheel 16 of control gear 17 mounted on top of the press, the driving motor 1 being similarly mounted and driving a flywheel 2 fixed to the layshaft 3, Fig. 2. The control gear includes two clutches 9, 10 and a brake 15. The housings of the clutches 9, 10 are fixed to gear wheels 8, 7 respectively and to the inside of each housing is fixed a group of clutch plates. In the spaces between these plates are corresponding groups of clutch plates fixed to collars 11, 12 splined to the driven shaft 6 of the control gear. A brake 15, of similar construction, has its housing fixed to a bearing 31. When the ram of the press is raised, i.e. when the crank is in position a, a compressed air cylinder 13 is operated by electromechanical means to cause an extension of its piston rod which projects into an axial bore in the shaft 6 to move a sleeve 29 (connected to the rod through transverse slots in the shaft in a direction to bring the plates of the clutch 9 into engagement. The same electromechanical connection causes the piston of a compressed air cylinder mounted in the housing of the brake 15 to disengage its plates, which are normally held engaged by springs, and release the brake. The layshaft 3 then drives the shaft 6 through gearwheels 4, 8, of small and large diameter respectively, and the crank turns slowly to cause the ram to descend on its working stroke. At the bottom of the stroke, position b, the compressed air to the cylinder 13 is shut off and the clutch 9 restored by springs to its disengaged position, and a cylinder 14 is operated to engage the clutch 10. The drive is then through gearwheels 5, 7 of the same diameter, giving a quick return stroke to the press ram.