Patent GB-604148-A (GB)
Title: Improvements in or relating to vibrating machines for consolidating materials in moulds
IPC: B28B1/087
Filed: 1945-08-13
Abstract: 604,148. Shaking-machines for moulding. SESSIONS, A. G. Aug. 13, 1945, No. 20798. [Class 87(ii)] A vibrating machine for consolidating material such as concrete in moulds comprising vibrating elements, conveying means to support the moulds for movement to and from the vibrating elements. and means for lowering and raising a vertically movable section of the conveying means, whereby a mould on the movable section may be lowered onto the vibrating elements and raised therefrom, has the raising and lowering means arranged to give a greater upward thrust when the movable section i,s in contact with the mould than when it is moving up to the mould. A mould M, Fig. 1, is moved on a conveyer 7 to the vertically movable section 11 of the conveying means. The mould is lowered onto the vibrating elements 20 by lowering supports 14, fixed to the section 11, by turning a handle connected through a shaft 31 to cams 32. Fig. 3, in contact with the supports 14. After the mould has been vibrated the supports 14 are raised and the mould removed .on the conveyer 8. The cam 32 has a flat part 32b changing at a fulcrum point 40 to an eccentrically arranged circular part 32a. While the conveyer is moving up to contact the mould the support 14 is raised quickly by the fulcrum 40 and when the conveyer contacts the mould the support 14 is raised slowly by the part 32a. When the flat part 32b of the cam abuts against a side 35a of the support 14 further upward movement of the section 11 is prevented. When the moulded articles are very heavy, a modified cam construction is provided in which the cam engages with a roller rotatably fixed to the support 14 and the cam has a groove into which the roller fits when the support 14 is in the lowered position. Counterbalance weights are fitted on levers fixed to the shafts 31. and the levers are so positioned that they exert a maximum turning effect when the section 11 contacts the mould during its upward movement. The weights are so proportioned that with the section 11 in its lowest position the torque on the shaft 31 is just insufficient to cause the section 11 to rise. Springs may be used in place of the weights. The vibrating means comprises the vibrating elements 20, joined by transverse members 21 to form a frame, brackets 22 slidable on spindles 24, rubber blocks 23 and resilient parts 26 to limit the upward movement of the frame 20, 21. The frame is vibrated by projections on discs 28, striking parts 27 on the members 21. In a modification discs 28 are replaced by cams so shaped that they lift the frame slightly and then allow it to drop onto rigid supports which replace the rubber blocks 23. The vibrating mechanism may comprise a unit having rotating unbalanced weights. The mould M is clamped to the elements 20 during vibration by clamping members 43, Fig. 6, forced downwardly, by springs 46, on to the flanges 53 of rails 52 on the bottom of the mould. In a modification the clamping members are forced down on to flanges on the walls of the mould. In both forms of clamping device the clamping members are freed from the mould, when it is to be moved along the conveyer by projections on the conveyer section 11. Specification 533,175 is referred to.