Patent GB-306762-A (GB)
Title: Automatic machine for the manufacture of artificial stones
IPC: B28B5/04
Filed: 1928-05-03
Abstract: 306,762. Escofet, J. M. May 3, 1928. Endless-chain machines; moulds; feeding; delivery; cleaning -apparatus; lubricating.-An automaticallyoperating plant for making decorated tiles is arranged with two parallel mouldconveying tracks between which the moulds aretransferred as necessary. Fig. 1 illustrates the lay-out of the apparatus, the three presses M being situated at one end. The pressed moulds are ejected three at a time, to the stations A<1> - - A<3> by laterallyacting mould-discharging mechanism and then are moved intermittentlv bv ratchet mechanism to the points B, C, D and E in turn. At point B the mould lids are raised and carried laterally by the conveyer 48 past cleaning mechanism for depositing in other moulds about to enter the press, while the walls are lifted and carried by the conveyer 40 past cleaning and lubricating mechanism for re-depositing on the mould bases at point D. At point C the tile is gripped, raised from the base, and turned through a right angle so as to be presented edge-on for delivery by hand. Between C and D the mould base is brushed and rubbed before the walls and base are reassembled at D. At E a stencil is placed in the mould, and at F colours are poured in which are distributed by vibration at the point G, the stencil being removed for retransferrence through a washing tank to point E. At points H and I the main body materials of the tile are added, while at K the mould lids are applied prior to the entering of the press at points L<1> - - L<3>. The moulds are fed laterally into the press M in groups of three from the stations L<1> - - L<3>, Fig. 1, by the bar 16, Fig. 3. carried by the shaft 14 actuated by the lever 17 and cam 15, the previously pressed moulds being ejected on to the parallel track at A during the movement. A weight 18 restores the shaft 14. A stop 21, Fig. 17, on the shaft 14 is utilized to operate the press in timed relation to the transfer mechanism, by operating the lever 23 controlling the valve gear 26 with a one-wav action; the press then remains operative until released by the cam 28. The mould carriers each comprise a platform 1 mounted on four legs carrying balls 3 running on tracks 4 having overhanging platform-positioning flanges 5. Each carrier has a projection 9, Figs. 5 and 9, on its under side co-operating with a corresponding number of pivoted weighted catches 8 on a reciprocating feed bar 7, whereby the moulds are advanced only during the forward movement of the bar, the catches 8 being tripped on the return movement, and the carriers held by sectional stop-members 11 on a rotating shaft 12 which are interposed between each carrier while the bar is receding and free it again for the next movement. In the press the upwardly-moving rams lift the carriers off the tracks before applying the pressure, no pressure being transmitted to the supporting-legs and the balls during the pressing operation. The moulds comprise a polished base plate 33, Fig. 5, bolted to the carrier 1 at 34 and centred by springs 74, together with a flanged frame 35 hinged at one corner to form two L-shaped members; a top member 36 completing the closure. At certain points in the track the handles 37, Fig. 7, on one frame member contact with fixed abutments to open the mould frame. Division plates for simultaneous manufacture of a number of tiles may be fitted in each mould. The opened frames and division plates are raised by conveyer chains 40, Fig. 2, furnished with cross members having depending hooks 44 which engage the flanges 45 of the frame. At the points 46, 47 brushing and lubricating devices respectively are passed upwards through the mould frames. The top members 36 are raised by hooks on a second conveyer 48, Figs. 2 and 4 which transport them laterally past rotary cleaning brushes 50 to the parallel track and re-deliver them to the filled moulds about to enter the press. After the mould frame and top member have been removed in turn, the pressed tile is gripped by the lifting-tongs 51, Fig. 16, which are opened momentarily against the action of a spring by' the depression of the plunger 53 actuated by a projection 55 on the carrier. One arm of the tongs engages before the other so as to move the tile laterally on the base plate to free it. The gripped tile is rotated about the axis 123 until released by lever 56 striking stop 124 in which position it is presented edge-on for removal by hand. After the tile has been removed, two edges of the base plate 33 are cleaned by the revolving brushes 61, Fig. 14, which are moved in one direction over the plate by the lever 58 actuated by the toothed sectors 64, and restored by the counterweight 65. Then the other two edges are cleaned by the brushes 70, 71 and simultaneously the main surface of the plate is cleaned by the endless cloth 67. The cleaned plate is then lubricated by means of an oiled pad advanced periodically from the side of the track by mechanism similar to that operating the brushes 61. At this point the base receives the cleaned frame from the upper chain conveyer 40. The vibrating-mechanism, for distributing the colours applied to the stencil, comprises a cam 81, Fig. 15 intermittently operating the axiallymoving shaft 80 which moves the pegs 79 on the member 33 and compresses those springs 74 surrounding the pegs on the opposite side of the member, the springs on the near side taking up the reaction. The stencil is removed from the mould and transferred through a water bath back to the point E by a tilting track 82, Figs. 2 and 29, fulcrummed at 84 and raised and lowered by cam mechanism 86. The track supports a travelling carriage 83 furnished with gripping dogs 95 opened momentarily to engage the stencil 104 on the downward movement by the pawl 100. On the up-stroke the carriage runs by gravity to the other end of the track, the dogs are re-opened by the pawl 109 and the stencil dumped on to a balanced platform 110, Fig. 12, in the water tank N. The axle 111 is moved bodily along the tank by mechanism engaging it at the point 119 and is caused to rotate by toothed wheels 117 engaging racks 118, thus dipping the stencils during the translation. On the quicker return stroke, which is performed by a counterweight, the racks are lowered by the cams 119 out of engagement with the wheels and the unloaded platforms are not dipped. At the other end of the bath a second tilting-track and traveller re-deliver the stencils to the next advancing newly-cleaned and reassembled moulds. This last track is undulating to shake off drops of water adhering to the stencils.