GB190907401A - Improvements in Type Casting Machines. - Google Patents

Abstract

7401. Link, R. P., and Hyde, A. G. March 27. Metal pots and pumps. -Fig. 3 shows a metal pot 5 having a cylinder 3 in which works a plunger 4 having a recess 16 engaged by a projection 14 on a valve-slide 2. A channel 6 in the slide 2 has ports 7, 8 at its opposite ends adapted to communicate with the mould 1 and a port 9 in the cylinder 3. The upper end of the cylinder is closed by a plug 17 containing a valve 19. The lower end of the plunger 4 is made hollow to contain a cushion of air in known manner. When the slide 2 moves down in its guideway 12, a partial vacuum is formed in the upper end of the cylinder 3, and, as the ports 8, 9 come into alinement, the air in the mould 1 becomes exhausted or rarefied. The continued movement of the slide carries the port 7 out of alinement with the mould and brings another port 10 into alinement with the mould and a port 11 in the cylinder 3. The plunger 4 first closes the supply port 22 and then forces the metal into the mould. The aperture 15 in the cylinder 3 through which the projection 14 passes may be vented by a hole 40. A vent-hole 21 communicates with the cylinder when the valve 19 is raised. Moulds for type-casting machines. The mould comprises slides the movements of which are synchronized with those of the valve-slide 2 ; in accordance with the size of a matrix presented between the slides so as to act as a distance-piece in known manner, the slides determine the size of the mould cavity without any manual adjustment being required. The slides may be hollow and may be cooled by jets of air. Four movable slides may be provided, but Fig. 1 shows three only, a fixed block 23 forming the fourth side of the mould. The slides 24, 25, 26 are independently reciprocated along their guides and, together with the block 23, have lugs 32, 33, which engage the sides of the matrix head ; the body dimension of the matrices is usually constant, and in this case the slide 24 always occupies the same position. The matrix rests upon plane surfaces 34 on the members 23 ... 26, and the edges of these members are suitably formed to produce a type body of the shape required. The connexion between the slide arms 29 and their driving-mechanism may be a spring or other yielding member. The valve-slide 2 forms a wall of the mould through which the metal is introduced. The valve-slide afterwards isolates the metal in the mould and renders subsequent trimming by a knife unnecessary. The valve-slide coacts with the pomp plunger as described above to produce a partial vacuum in the mould.