GB663040A - Improvements in and relating to presses for producing compacts from pulverulent materials - Google Patents

Abstract

663,040. Moulding powdered material. PRIMAVESI, D. Dec. 29, 1947 [Dec. 4, 1946], No. 34534/47. Class 87(ii) Apparatus for compressing powdered material, e.g. powdered metal, comprises a die 1 movable relatively to a platen 10, an upper pressing ram 5 and a lower ram comprising a number of ram members 12, 13, 14 movable relative to each other. As shown one member 12 is fixed to the platen, which is stationary, and two members 13, 14 are vertically slidable in the platen and may be urged downwards by springs 19. The die 1 is carried on rods 8 sliding in the platen 10 and secured to a cross piece 9 which is moved up and down by a shaft 11 connected to the press operating mechanism. In Fig. 8 the die 1 and ram members 13, 14 are in their uppermost positions, the ram members being urged upwardly by the crosspiece 9 and limiting the upward movement of the die. The die is charged with powder and the upper ram 5 brought down, forcing down the ram members 13 and 14 until shoulders 25, 26 thereon engage horizontally slidable stops 20, 21 on the platen 10, the die also moving down. Pressure on the ram 5 is then relieved until it is reduced to that exerted by a spring 6 interposed between the ram 5 and its operating mechanism. The die 1 is then moved down to clear the moulded article by means of the cross piece 9, inclined projections 23 on the rods 8 engaging rollers 24 to move the stops 20, 21 against springs 22 from beneath the ram members 13, 14. The ram members are then moved down by the springs 19 and/or by the die 1 engaging the shoulders 25, 26, to clear the moulded article, Fig. 10. The ram 5 is then completely withdrawn and the article removed. Movement of the cross piece 9 upwards restores the Fig. 8 position. 'The arrangement is such that no lower ram member is moved down until the whole of the article above that member is relieved of side pressure from the die. Means are provided for adjusting the initial positions of the lower ram members and the die. Both upper and lower rams may be subdivided into ram-members. The die 1 may be stationary and the platen 10 movable, together with its attachments, or both die and platen may be movable to obtain the required relative motion thereof. Specifications 589,863 and 610,011 are referred to. The Specification as open to inspection under Sect. 91 states that the die may be in more than one part, the parts being movable sideways to release the lateral pressure on the moulded article. This subject-matter does not appear in the Specification as accepted.