GB1314436A - Method and apparatus for injecting a fluid into powdered materials - Google Patents

Abstract

1314436 Moulding powder WOLVERINE PENTRONIX Inc 3 Aug 1970 [10 Nov 1969] 37315/70 Heading B5A Apparatus for the production of fluid saturated compacted articles comprises one or more die cavities 28 in a die-plate 22 supplied with powder 29, an anvil 31 which closes the powderfilled cavities, punches 54 which compress the powder in the cavities, and means for injecting a fluid into the powder in the cavities prior to compacting the material comprising a passage 74 which opens into each cavity between the anvil and a punch 54, which punch closes the passage during compaction to meter the amount of fluid injected. The fluid is supplied from a pressure source 76 and passages 70, 74 in a stationary core rod 62, and the punches are secured to a holder 42 raised by a member 48 and slidable in a housing 30 bolted to the dieplate. In the embodiment of Fig. 3 the core rods are omitted and the fluid is supplied to the punch housing 30a from a pressurized source 87 via a valve 89 actuated by a rotary cam 91, and a supply line 88. The fluid is held above the holder and injected into the powder filled cavities via passages 90, 92. A predetermined amount of fluid is supplied to the housing and die cavities on timed actuation of the valve 89 whereby the fluid is supplied from the source by a pump 99; during the greater part of the press operation the line 88 is connected via the valve 89 with a line 85, and provides for refilling of the housing when the punch holder moves down to the powder-fill position. In a further embodiment the fluid is fed into the die cavities via passages formed between the upper ends of the punches and the inner walls of the dies, Figs. 5 and 6 (not shown). An embodiment is described in which core-rods with axial bores and transverse injection passages extend axially into the die cavities similarly to that shown in Fig. 1, but which are slidably disposed in the punch housing, and fluid to be injected is supplied to the housing below the punch holder and passes through further transverse bores in the core rods to their axial bores. In Fig. 9 the fluid is injected through orifices 112 of an axially reciprocable core rod which recedes as the punch is raised and so that the rod and punch form a single unit during the final compression stroke.