Cap-forming drawdown tool uses specified projections on punch flat face to seal to bottle rim in first drawdown and second forming passes.

摘要

The flat face (31) of the punch (27) has a first projection (33) parallel to the bottle mouth at spacing (A2) not greater than spacing (A1) plus the draw depth (Z). The surface (41) of this projection (33) facing the mouth is flat as compared with the outer flank (45) of projection (33) which is convex at the transition from the face (41). The transition radius should be 0.5 mm so the height (H1) of projection (33) is 0.5 mm in relation to the flat face (41). The projection (33) is round, with an outside diameter of 15.5 mm and less than that of the punch (27) face (31). The inner flank (43) of a central hole in the projection (33) is at right angles to the projection (33) face (41) and the flat face (31) has a second projection (34) concentrically ringing the first (33), and arranged (34) at the flat face rim. The inside flank (51) of the second projection (34) is concave of radius 1.8 mm. Opposite to its flat face (31) the punch (27) is spherically curved in contour.