Patent GB-190620213-A (GB)
Title: Improvements in or relating to Apparatus for the Manufacture of Curved Stereotype Plates.
Inventor: ANNAND ROBERT CUMMING
Filed: 1906-09-11
Granted: 1907-06-06
Abstract: 20,213. Annand, R. C. Sept. 11. Stereotype.-In apparatus for casting and trimming stereotype plates, the plate after being cast in the mould is conveyed to the boring-bed by a rotating and swinging core, which is preferably collapsible to bend the plate away from the matrix. The boring-bed then slides transversely with the plate to beneath the boring-cylinder with its knife and driver bar. Guiding-stops, some movable, and stationary cutters for trimming the edges are provided. The finished plate is delivered on to a table, and the machine automatically stopped. The pump for supplying the metal is actuated by spring or weight mechanism which is set and released automatically at the proper times. The mould 22, Figs. 3 and 18, supported on suitable brackets, is provided with hinged clamping-pieces 108, 109 to clamp the straight edges of the matrix, and also the curved strips which overlay the side edges of the matrix and form the sides of the mould. The clamps are operated by eccentrics on the spindles of bandles 121 closing against stops. The curved strips fit.partly into grooves in the mould, formed at suitable distances according to the width of plate required. The upper clamp 108 forms with the part 115 of the core, the extension of the mould in which the '' get " is cast. The core is preferably collapsible, and has the grooves for casting the ribs on the stereotype plate slightly undercut, so that when the mandrel is collapsed the plate is bent and drawn away from the matrix. In one form, the core consists of two parts 41, 41<a>, Fig. 3, hinged together at 132 by adjustable hingepieces and supported by slotted arms 134 attached to the shaft 36, and engaging at one end extensions of the hinges 132. At the other end, the segments 41, 41<a> are supported by links 135, adjustably pivoted to the segments at one end and to the arms 134 at the others, and arranged out of line with each other, as shown, so as to act as toggles. A strong spring (not shown) tends to close in the two segments, but during casting this action is resisted by links 35 which, as in the position shown, pull the shaft 36 and therefore the arms 134 to the right of the centre of the core, causing the links 135 to expand the core. In this position; the mould is ready for the casting operation. The metal is forced through a suitable pouring-nozzle by a pump operated by a weight or spring. This spring or weight is first set by a cord 96<a> wound round a loose pulley on the shaft 33 which reciprocates intermittently. A catch 102 releases the pulley and allows the pump to act just before the shaft 33, carrying the disks 34 operating the levers 35, comes to rest in the position shown, with the core fully expanded. The shaft 33 is driven through gearing from a shaft 19, driven through the clutches 21 and bevel-wheels 16, 17 in reverse directions with intervals of rest of suitable length between, all being automatically determined by the cam 21<a> operating the bell-crank lever 67. When the metal has solidified in the mould, the motion of the disks 34 is automatically reversed as above mentioned, and the core is contracted so that the ends of the cast plate clear the matrix. Further motion of the links 35 rolls the core on the side spur-wheels 42 and stationary segments 43 into the boring-bed 23, Fig. 5. This motion is controlled by levers 38 mounted on a shaft 171, and the core is balanced by a weight 39. When in the boring- bed, the core is again expanded, and catches, which only work by gravity when the core is inverted, operate to hold the core in its expanded condition on the return movement, during which the plate is first stripped from the core by sliding cam-operated catches 58 engaging the upper edge nf the plate, and adjustable but fixed catches 60 engaging with the corners of the matrix on each side of the get, which is slightly narrower than the matrix. The part 115 of the core also breaks off the get in its return motion. A hollow 145, Fig. 5, is packed with asbestos to prevent leakage of metal through the joint between the segments. Three or more segments may be employed. In a second form of contracting core, Fig. 18, the lower part 153<a> is fixed to the shaft 160, and the segment 153 is hinged to it by a hinge adjustable to take up wear, and moved to expand or. contract the mould by rollers 164 engaging with cam-slots 165 formed in the heads of the levers 38, which in this case are mounted on a shaft 171 in eccentric bearings 172 rocked from a cam 177 on the shaft 33. The holes in the heads of the levers 38 through which the shaft 160 passes are slotted, and in order to allow the core to be contracted before its rolling motion begins, the holes 160<a> in the levers 35 are also slotted, as shown. The boring-bed 23, with the plate in it resting against the stop 56, is traversed by a cam 44, Figs. 2 and 5, on the reciprocating shaft 19, to beneath the boring- cylinder 47, the straight edges of the plate being planed during this motion by tools in the sockets 46. The cylinder 47 is continuously rotated by a worm 14 and wheel 15. A sliding stop-plate 59, operated together with the stop - plate 58 by the cam 62, Fig. 3, holds the plate during the boring operation, after which the plate 59 is retracted and the driver bar 53 pushes the plate out of the boring-bed, round the cylinders, and on to the table 61, the curved edges of the plate being finished simultaneously by fixed cutters 57. The driver bar 53 is only projected in the path of the plate when the boring-bed is right under the boring-cylinder, and the stop 56, Fig. 5, engages with the pin 82 and presses it to the left against the action of a spring. The stop 59 and the edge of the table 61 are stepped, as shown, to clear the stepped edge of the driver bar. The operations are so timed that one plate is being cast while the previous plate is being bored. At the end of the boring operation, the machine is automatically stopped by a projection on the wheel 63, Fig. 3, engaging with a sliding bar (not shown) carrying belt-shifting mechanism which-shifts the belt from the fast pulley 8 to the loose pulley 9. On restarting the machine, the cast plate is delivered to the boring-bed, and the finished plate on to the table 61.