Patent GB-279503-A (GB)
Title: Improvement in jigger mechanism for use in the manufacture of pottery and like articles
IPC: B28B1/02
Filed: 1927-10-22
Abstract: 279,503. Miller, W. J. Oct. 25, 1926, [Convention date]. Pottery, throwing and turning.-Potteryshaping mechanism comprises a supporting member 63 recessed to receive a mould 62 carried by a reciprocable and rotatable chuck 60, and means are provided to rotate the chuck after it has raised the mould out of contact with the supporting member and before the mould reaches the operative shaping position. The spindle 12 slides at its upper end in a socket 54 in an extension 56 of the main frame 11, and its lower end is disposed in a bearing 37 in the main frame. A friction gear 22 is adjustably mounted on the spindle 12 and is adapted, when the spindle is raised, to engage a tapering face 21 on a gear 15 mounted on a shaft 14, which is disposed in a bearing 13 in the frame 11. The spindle 12 is adapted to be raised by means of a lever 27 through mechanism consisting of a vertical rod 29 and a fork 25 swivelled on a neck 26 on the spindle. The spindle is normally retained in lower position by a spring 28 attached to the rod 29. The friction gear 15 is slidably mounted on the shaft 14 and is kept in contact with the gear 22 by means of a spring 17, which is adjustably positioned on the threaded end 19 of the shaft 14. Collars 16a, 16 are mounted on the shaft 14 to prevent respectively the endwise movement of the shaft and the movement of the gear 15 on the shaft. Stepped pulleys 49, 50 serve for revolving the shaft 14. The periphery of the gear 22 is provided with a leather band 22a, the upper part of which engages the inclined surface 21 of the gear wheel 15 and the lower part fits the surface of a brake 33. The brake is mounted in a circular recess in the frame 11 and rests on springs 35 which are adjustable by screws 75. The flanges of the brake sections are secured together by bolts 36a and separated by springs 73 as shown in Fig. 3. The upward movement of the brake is limited by stops 36 provided on the frame 11 and adjustable by means of screws. A filler block 77, Fig. 4, is disposed between one pair of flanges of the brake and a spring 78 is placed between one flange and the nut on the connecting bolt 36a. The horizontal mould-supporting member 63, having a central opening 74, is adjustably connected to the frame extension 56 by bolts 64 passing through slots 66. When the spindle 12 is lowered the member 63 intercepts and supports the mould 62. The profile member 61 is secured to an extension 53 of the frame 11 by means of screws passing through slots 61a, 61b. The spindle 12 is normally raised from the pivot bearing 37 and is supported in position by the brake 33. On lifting the spindle, rotary motion is imparted to the spindle gradually by reason of the taper of the face 21. The springs 35 under the brake 33 serve to advance the action between the brake 33 and gear 22, when the latter is lowered with the spindle 12, in order to stop the rotation of the spindle before the mould 62 is intercepted by the member 63. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the following modifications :-(1) The profile 61 may be of rotary type and the mould may rotate or be mounted on a reciprocating rod. (2) The spindle may be intermittently rotated with gradual acceleration and retardation. (3) The mould may have reciprocal motion to co-operate with a member for releasing the latter from the chuck. (4) The chuck 60 may be actuated by means other than the spindle 12. This subject-matter does not appear in the Specification as accepted.