GB137603A - Improvements in foundry moulding machines - Google Patents

Abstract

137,603. Lawrance, S. Jan. 20, 1919. Moulding-machines; clamping moulds.-Turnover table moulding-machines fitted with swing press-heads have a direct hand actuation during the greater part of the stroke, the final pressure being applied through means such as an hydraulic jack device. A hand-lever 28 linked to the ram head 13 at 30, 31 raises the head together with a trolly 46 running on flanged rails for facilitating removal of the moulds. Rods 39 provide for the lowering of the press-head 36, which is locked in place by automatic catches actuated by springs 43 on rods 41 connected to the ram-head. During the stroke, the turn-over table 1 is raised from its stops 4 on the press-columns, and fixed springs 10 unclamp the upper flask and clamp the lower. During this part of the stroke, liquid passes freely from above to below the main piston 15 through a valve 27. A small piston 19 working inside the main piston-rod is raised with the main rod by a spring 32. To apply final pressure, a treadle 20 connected to the cross-head' 18 is actuated for a succession of strokes, the piston 19 transferring fluid from above to below the main piston as controlled by ball valves 22, 23. For drawing, the valve 27 is positively opened by a cam 50 actuated by a lever which is automatically moved to close the valve by a tappet 52 at the end of the drawing-stroke.