Patent GB-1164013-A (GB)
Title: Method and Apparatus for Die Casting Key Plugs
Inventor: SPAIN ROY CLIFTON
IPC: B22D17/22
Filed: 1967-01-27
Abstract: 1,164,013. Casting metals. NATIONAL LOCK CO. 27 Jan., 1967, No. 4284/67. Heading B3F. [Also in Division E2] Several key-receiving plugs, Figs. 15-19 (not shown), for lock assemblies are pressure die-cast in a machine simultaneously, each being cast in a cavity formed by a cylindrical bore 72 (in one of a number of die blocks 69, Figs. 5, 6, and closed at the lower end by a core 74) and by a circular recess 37, Fig. 3 (in a core 31 located over the top end of the bore 72) when a lower platen 13, Fig. 1, is raised bearing a lower mould-and-ejector assembly 18, Fig. 5, to close against a mould member 17, Fig. 3, secured to a stationary upper platen 14. The cores (mould ends) 31, Fig. 3, are held by screws 32 in sockets 29 in an upper die plate 19 which has a generally circular periphery, Fig. 2 (not shown), and a central, raised portion 27 with runners 33 radiating from a central sprue (34) to the cores 31, arranged in a ring at the edge of the portion 27 in radial extensions 28 thereof. A central plate 38, retained by a pin 39 in each core recess 37, extends to enter the die bore 72 and form the mouth of the plug key-way; it may also be shaped to form part of the keyway and wards. The lower die plate 56, Fig. 5, has a ring-shaped block 59 secured on top of it by screws and with an inner periphery 62 complementary, Fig. 4 (not shown), to the outline of the upper die portion 27. The block 59 overlaps die recesses 68 to retain the die blocks 69 therein. On closing together the parts 17, 18, camming pins 42a, 42b, 42c enter passageways 84 in slide blocks 81, 82, 83 to urge the latter radially towards the mould cavity in the die bore 72 carrying side cores 86, 92, 97, also radially so that they abut each other, Fig. 6, in the bore for forming the key ward and tumbler slots in the cast plug. Camming pins 43 also enter passageways 114 to move cam slides 109 radially, i.e. towards a centre sprue post 64 of the die plate 56 and guide pins (44) enter pin bushes (65). The inner end (112, 112a), Fig. 4 (not shown), of each slide 109, wedge-locks the ends of pairs of adjacent slides 82, 83 and a lock 46, Fig. 3, on the upper mould member 17 abuts the end 111 of the slide 109 to resist outward pressure during casting. Similar locks 45 do the same for the slides 81. The lower platen 13, Fig. 1, reciprocates on guide rods 15 and when raised by a ram 12 to the upper platen 14 bearing a melt source 16, push-back pins 122, Fig. 5, extending through the die plate 56, are pushed back flush with its surface 61 by the upper plate portion 27, Fig. 3, to retract an ejector plate 119, 121 to which are secured, like the pins 122, casting-ejector pins 117. The ejector pins 117 pass through holes 116, Fig. 6, in the die blocks 69 to act on the rings of sprue in the core recesses 37 after casting. Stationary rods 151, Fig. 1, secured to the machine base 11 may cause the ejector assembly to stay up and thus operate as the platen 14 descends. Sleeves 58, Fig. 5, support the die plate 56 from a base 54 which is secured to the platen 13 and cooling water from a junction 124 is passed through the plate 56 when molten metal under pressure has passed into the die cavities from the source 16. Moulders' tools.-If a die block 69 or its bottom closure core 74 is to be removed for changing, the ring 59, Fig. 5, or back-up plate 77 is removed and an extractor tool (135), Figs. 11, 12 (not shown) or (126), Figs. 13, 14 (not shown), is attached by screws or its screw (128) and then a nut (139) or the screw is turned against a bracing member to draw the member out.