GB757603A - Centrifugal casting machine - Google Patents

Abstract

757,603. Centrifugal casting machines. BUNFORD, M. A. Sept. 24, 1953, No. 26392/53. Class 83 (1). A centrifugal casting-machine comprises a hollow shaft with its ends projecting beyond the framework in which it is mounted, driving means associated with the central portion of the shaft and a mould carried by one end of the shaft, which has a groove engaged by a tenon or tenons on the mould so that the mould is rotatable with and readily removable from the shaft. The framework comprises two plates 4, 5 in which are ball and roller bearings for the driving-shaft 11 and the driven shaft 1, in the end of which is the groove 16. The shaft 11 is driven from a motor 13 through gear 15 which can be engaged or disengaged by a lever, not shown. The shaft, when disconnected, may be brought to rest by a brake, not shown. The drive is transmitted to the shaft 1 by a belt and pulleys 8, 9. The cover 19 may be hinged to the mould, or may be separate and held in position during casting by a hand-lever 21, Fig. 2, pivoted about the mould-filling funnel 22 in the cover 19 and, when moved, co-operating with grooves 26 in pintles 27, the engaging surfaces being inclined to produce a wedging action and force the cover 19 on the mould 20. When the cover is hinged it may be held to the mould 20 by the centrifugal force of a mass 57, Fig. 10, on the end of a pivoted arm, causing a hook 55 on the arm to press on the edge of the cover. Disengagement, when rotation ceases, may be assisted by raising a plate 17 by hydraulic jacks 18, Fig. 1, whereupon inclined abutments 58 on the plate act on the mass or masses 57. The plate 17 may also carry pins which raise the mould cover and eject the casting. In a modification, two masses on arms 35, 36, Fig. 8, fixed to the mouldcarrying shaft, contact two flanges 38 depending from the mould bottom when the shaft rotates and the mould is driven by them. The initial short rotational movement also moves an arm 42, Figs. 6 and 8, pivoted on a pin 39, so as to swivel a tail-member 44, mounted in a ball-andsocket joint 43 in the arm 42, and cause it to turn a bar 29 about a rod 30. The bar 29 engages steps on the mould 20 and cover 19 to lock them together. When the mould-carrying shaft is braked, the action is reversed and the mould is freed, allowing the cover to be opened. As the arms 35, 36 rotate, inclined surfaces underneath them ride under rollers 47, Figs. 5 and 8, on pins 48 and raise pistons 49. This raises a loose mould-bottom 53, and when rotation ceases the bottom is returned by a spring 51 to free the casting. Cores on rods 59, Fig. 3, may be inserted by the centrifugal action of masses 63 on arms 62 pivoted at 60. Specification 734,064 is referred to.