Patent GB-190412007-A (GB)
Title: Improvements in Means for Casting Stereotype Printing Plates.
Inventor: LOCK WILLIAM HENRY
Filed: 1904-05-26
Granted: 1905-03-30
Abstract: 12,007. Lock, W. H., and North, T. M. May 26. Stereotype. - Relates to stereotypecasting mechanism and particularly to the type described in Specifications No. 18,742, A.D. 1897, and No. 28,233, A.D 1902. The molten-metal pump 3, Fig. 1, dips into the melting-pot 29, and is adapted to slide obliquely in grooves 6, 7 towards and away from the mould formed by the cylinder 9 and the matrix supported on a segmental backing 47. The pump 3 is driven from a toothed segment 13, pivoted on a pin 14 and carrying a roller 12 which engages a face cam 11 on a shaft 10. The segment 13 gears with a similar segment 15 on a shaft 16, carrying a crank 17 connected by a link 18 with a crank 19, which communicates motion to the pump by means of an adjustable link 20. The pump plunger 21 receives its vertical reciprocating motion from a face cam 22 on the shaft 10, with which engages a roller on a pivoted lever 23, communicating with the plunger 21 by means of a link 25, crank 26, and mechanism 28. The discharge orifice 2 of the throat 1 extends the full length of the matrix, and is made of double the usual cross-section, a valve 4, Fig. 5, being provided for cutting off the supply of metal when the plate is cast. The valve 4 is mounted on a shaft 31, pivoted in the sides of the mouthpiece 5 and provided with an arm 32, to which is connected the lower end of a rod 33 passing through a pivoted socket on an arm 34 carried by the shaft 27. The rod 33 carries two collars 35, 36, which, during the operation of the machine, are engaged alternately by the socket 37 on the arm 34. A pivoted pawl 40 is adapted to engage a recess in the boss of the lever 32, to retain the valve 4 in the raised or open position, until the pawl is disengaged from the lever 32 by a collar 43 on a rod 44 which is connected to the arm 34 and slides in a guide 45. The mouthpiece 5 is provided with a valve 46 for preventing the formation of a vacuum in the throat 1. The pump piston is provided with spring buffers and is arranged to be raised rapidly at the commencement of its operation, and then to exert a pressure on the injected metal to force it into the interstices of the mould. To avoid cooling the metal in the melting-pot by the continued addition of fresh ingots, the metal is first melted in auxiliary melting-pots, placed at a higher level than the main melting-pot and heated by gas burners. Each auxiliary melting-pot is fitted at the bottom with a valved pipe by means of which the molten metal is conducted to the main pot. The main melting-pot may be arranged to supply several casting-machines with metal, if desired. The circular saws 53, 54, Fig. 13, for trimming the edges of the plate after it has been removed from the matrix and rotated through two right-angles, are driven independently of the casting-mechanism, thus allowing the casting-mechanism to be thrown out of action without stopping the saws. This is effected by driving the vertical saw spindles 55, 56 by separate electric or steam motors, or by the arrangement shown in Fig. 13. The driving shaft is made in two parts 61, 62, capable ot being connected together by a clutch 63. The shaft 62 is driven by means of a belt on a pulley 64, and drives by means of bevel gearing 65, 66, 67, 68 a vertical shaft 69 carrying a pulley 70 at its upper end. The saws are driven by a belt 71, passing around the pulley 70, a jockey pulley 72, and pulleys 73, 74 on the saw spindles.