| 摘要 |
1,132,434. Moulding concrete blocks. COLUMBIA MACHINE Inc. 24 Jan., 1966 [27 Jan., 1965], No. 3102/66. Heading B5A. Apparatus for making concrete blocks comprises a vertical frame, means for suspending and vibrating a mould within the frame, and a pallet lying loosely on a pallet holder mounted below the mould, the pallet holder being supported on air-filled cylinders or cushions by which the pallet can be raised into contact with the lower surface of the mould. The mould 31 is mounted in a frame 69 which is vibrated vertically by collars 78 mounted eccentrically on shaft 80. The mould base is formed by pallet 103 which rests on pallet holder 101 loosely attached to member 23 by bolts 27 and resting on springs 107 and pneumatic pistons 105. Member 23 is rigidly connected to horizontal bar 21 and which is connected to vertical sleeves 7. Bar 8 joining the sleeves 7 is connected at its midpoint to piston 10 of stripper cylinder 11 secured to bracket 13 attached to the main frame 1. Sprung side pieces 17 limit the travel of bar 8. Rods 50 mounted at the base by springs 57 and pivoted links to bar 60 and at the top to cross member 47 serve to absorb sudden shocks on the mould. A set of valves are also supplied so that by means of a pressure regulator, the pressure in pistons 105 can be set to any one of several predetermined values. Different pressures may be used at different points in the cycle, e.g. during filling and vibrating and these may be controlled manually or automatically. The mould, pallet and pallet holder are arranged to have different amplitudes of vibration. In operation, for part of the cycle the mould will be clear of the pallet and the pallet will also clear the pallet holder. As the pallet bonds it will be twisted by springs 107 and this will produce a trowelling effect on the base of the concrete block. Motion of the block relative to the mould produces a similar effect on its sides. Excess water and air can escape from the top and bottom of the block, but no leakage of concrete occurs at the base. |
