GB831330A - A new or improved method of and apparatus for the manufacture of coloured ceramic ware - Google Patents

Abstract

831,330. Moulding ceramic articles. WORCESTER ROYAL PORCELAIN CO. Ltd. March 25, 1957 [March 24, 1956], No. 9254/56. Class 87(2). [Also in Group X]. Coloured ceramic ware is made by applying coloured material in liquid form to the surface of a rotating mould, then forming the ware by applying ceramic material in mouldable form to this mould and finally removing the hardened moulded ware with the coloured material adhering to it and finishing it by firing &c. The ceramic material may be applied in a plastic state and moulded by shaping tools or manually, or it may be in liquid form and shaped by casting in a mould. The coloured material comprises ceramic material, colouring material and an aqueous liquid. To facilitate application of the coloured material to part of the mould, that part may be removable, or it may be recessed as at 151, Fig. 3. Apparatus for use in applying coloured slip to an annular zone on a mould comprises a cabinet 20, Fig. 4, having two opentopped chambers 21, 22, each containing a rotary mould support 27, 28 respectively ; the support 27 which is driven by a motor 42 has associated with it a nozzle 14 connected to supply container 63. Coloured slip is conveyed to the container 63 from a main tank by a pipe 90 connected to a pump 89 which also is driven by the motor 42. The nozzle 14 has an outlet of the same width as the annular zone to be coated, the flow of slip being controlled by valve means. The nozzle is slidable radially with respect to the mould and is adjustable angularly, the angle between the flow of slip and the surface of the mould being in the range 15 to 25 degrees. Also associated with the chamber 21 is a spray nozzle 95 for supplying wetting liquid to the mould prior to the application of coloured slip. The rotation of the support 27 is controlled by pneumatically operated clutch and brake ; the pneumatic actuating devices for controlling the clutch, brake, nozzle slide, nozzle valve, and the control valve for the wetting nozzle 95 are operated in timed relation by means of cams 118-122 on the cam shaft 136. To remove any surplus coloured slip from the area 18 of the mould beyond the recess 151, the mould is transferred to turntable 32 driven by a separate motor 153, and is acted on by a scraping tool consisting of a wire held in tension between the limbs of a bifurcated holder. The scraping tool can also be actuated pneumatically. The Provisional Specification describes also apparatus having more than one nozzle for applying coloured slip so that different colours can be applied simultaneously. The nozzle may also be movable radially during rotation of the mould so that a non-circular, e.g. wavy. band is applied.