GB549497A - Improvements relating to the centrifugal moulding of concrete pipes and the like - Google Patents

Abstract

549,497. Moulding and lining pipes in centrifugal machines. HUME, W. R., and HUME PIPE CO. (AUSTRALIA), Ltd. May 21, 1941, No. 6542. [Class 87 (ii)] The end plates 3 have central annular flanges 6 of small diameter which rest upon rollers 7 and so support the mould that the centre of gravity of the mould is lowered. The end plates have a series of circular rows of bolt holes (not shown) whereby mould casings of different diameters may be attached thereto. The end plates may project beyond the casing 3 and may have heavy rims which strengthen the plates and impart a flywheel effect thereto ; these heavy rims may contact with mechanically or hydraulically intermittently-operated jolting rollers to compact the semi-dry concrete mixture in the casing. Alternatively, the jolting may be effected by means of (a) stepped end plates engaging rollers, or (b) a stepped cam or wheel 9 which engages the bare rims of the plates 3 and is adjusted by a screw device 17 via link 16, arm 14 and eccentric 11. The flanges 6 define a central aperture through which extends a hollow shaft 19 secured by brackets 21 to levers 23 pivoted at 24 on brackets 26 on the main frame 5. Arms 27, 44, extending from the shaft 19, carry respectively a screeding roller 18 and a screeding bar 42. The roller 18 may be locked at each end against rotation by inserting the keyed end 34 of a locking spindle 33 into a recess 35 in the roller ; this insertion is effected by fitting a crank handle to the slotted end 39 of a shaft 38 and rocking the latter so as to depress the spindle 33 by means of a link 37. The spindles are held in their raised, retracted position by spring catches 40.- The arms 44 carrying the screeding bar 42 are pivoted on the shaft 19 and are rigidly connected to the arm 27 by a pin-and-slot connection 45, 46. Ropes or chains 51, 51a connect the bar 42 and pin 46 to a winding spindle 48 by means of which, after an initial screeding has been effected by the bar, the pin may be withdrawn and the bar raised to allow the roller 28 to operate alone. Downward pressure may be exerted by the levers 23 on the concrete through the medium of the screeding members. The casing is driven by means of bands 54 passing therearound. By securing the end plates to a metal or other pipe, the pipe may be lined.