Patent GB-845627-A (GB)
Title: Apparatus for production of edge-type filter elements
Inventor: MCLEAN GEORGE ARCHIBALD
IPC: B21F27/18
Filed: 1958-12-11
Abstract: 845,627. Making filters; coiling welding by pressure; rolling. PUROLATOR PRODUCTS Inc. Dec. 11, 1958, No. 40056/58. Classes 83 (2) and 83 (4). Apparatus for making edge-type filter elements comprises co-operating means for forming spaced projections on a metal wire, a rotatable mandrel for winding the wire thereon, means for welding said projections on one turn of wire to the adjacent turn of wire wound on the mandrel and means for passing the wire from a source of supply to said co-operating means and then to said mandrel. Wire 34 is fed from a fixed spool 33, Fig. 1, over a pulley 35 by a conical driving-roller 38 and a conical driven roller 37, the latter having a grooved working surface. The rollers 37, 38, Fig. 9, impart a predetermined curvature to the wire and at the same time form it into flat ribbon having alternate grooves 45 and projections 46. A mandrel 23 is centred in a mandrel frame 13 comprising a U-shaped portion 14 and hollow cylindrical endsections 16, 17 supported to slide axially in frames 11. The mandrel 23 is rotatably driven by a motor 20, mounted on the sliding section 16, through a belt-drive and a shaft 18. Rollertype welding electrodes 49, 50, mounted on arms attached to a mechanism 55, stationary in a direction axially of mandrel 23 and supported on the base 10, are movable towards and away from the mandrel by means of a screw 55A. As the mandrel 23 is rotated and moved to the right of Fig. 1 by a screw-feed drive 27, the formed flat ribbon 34 is received from a guidetube 47, Fig. 3, and continuously wound on the mandrel, the face 57 of the roller electrode 49, Fig. 13, pressing the last-formed turn 59 of the winding against the penultimate turn 58 while a welding current is passed from the electrode 49 to the electrode 50 which bears against the side of the coil of ribbon on the mandrel. The projections on each turn are thereby spot-welded to the plane face of each previous turn. Cooling water may be fed through at tube 59a. In making flat edge-type filter elements, a wire 34 is fed from a spool 63, Fig. 6, mounted on a base 61, by rollers 66, 67, the roller 66 having depressions in the periphery while the roller 67 is circumferentially grooved so that the wire is flattened and also formed with spaced projections on one side, Fig. 12 (not shown). The leading end of the formed ribbon is then inserted between a knurled roller 86 and a freely-rotating mandrel 71, Fig. 7, the knurled roller driving the mandrel to wind the ribbon on the latter. Each turn of the winding is welded to the previous one as before by a current which passes from a roller electrode 74 through the last two adjacent turns to one or other of roller electrodes 77, 78. The mandrel 71 and the wound ribbon are rotated by the weighted knurled roller 86, the mounting 84, 85 of which is vertically slidable on posts 82, 83, the roller being driven by a chain-drive 87 connected with the drive 65 for rollers 66, 67. As the diameter of the wound strip increases the mandrel 71 is permitted to rise by the sliding of the mandrel support on posts 70, Fig. 5 (not shown). The welded ribbon may be water-cooled as before.