Patent GB-657136-A (GB)
Title: Method and apparatus for making wire netting
IPC: B21F27/06
Filed: 1948-11-09
Abstract: 657,136. Making netting. INDIANA STEEL & WIRE CO. Nov. 9, 1948, No. 29101. Convention date, Dec. 8, 1947. [Class 83 (iv)] [Also in Group I] A method of producing wire netting of the type in which each o a set of a plurality of mesh wires A<SP>1</SP> B<SP>1</SP>, Fig. 24, is offset alternately into association with, and secured to adjacent wires on opposite sides of it comprises the steps of feeding the wires over pre-determined paths successively to separated pre-forming and joining stations, pre-forming the wires at the pre-forming station t( produce in each a series of longi tudinally-extending, laterally-offse portions inter-connected by trans versely-extending portions, bringing the pre-formed mesh wires into association at the joining station witl the wires to which they are to be secured and securing each offset por tion to the coinciding wire. In a machine for carrying out the method a set of unformed wires to form the mesh wires A<SP>1</SP> and line wires C are fed into the machine over rollers 29 30, and a similar set of wires to forn the mesh wires B<SP>1</SP>, and line wires C are fed over the rollers 33, 34, as shown in Fig. 1. The mesh wires are then passed to forming drums 27, 28 and the line wires byepassed over rollers 36 to a twisting drum 26. Each forming drum comprises a number of axially-extending fixed bars 54a, Fig. 4, and a number of similar bars 54b which are arranged alternately with the fixed bars and are movable by means of rollers 66 engaging on a fixed cam 68 on the shaft of the drum. Both sets of bars 54a, 54b carry on their outer faces a series of axially - spaced forming elements constructed as staples 55. As the rollers 66 progress along the cam slope, 70, which is shown in developed form in Fig. 9, the mesh wires pass between the fixed and movable staples and are gradually shaped; they leave the drum at Q. The formed wires are then passed through guides 31, 35, Fig. 1, and are pressed by means of freely-rotating wire-seating rolls 40, 41, through slots 791, Fig. 10, into the slots of twister gears 89, carried on the twister drum 26. The rolls 40, 41 also seat the line wires which are laid under or over the mesh wires according to the position of the rollers 36. The twister gears are turned by racks 92 controlled by stationary cams 109 contacted by rollers 108. The cam 109 is shaped to overtwist the wires and then slightly reverse the rotation of the twister gears, so relieving the tension of the wires in the gear slots. Slots 91 accommodate the line wires between consecutive twists. Working forces are confined to the drum by providing similar cams 109 at each end thereof so as to act in opposite directions, giving reversed twists in adjacent transverse rows of the wire as seen in Fig. 24. Torsional forces are relieved by rotating each end of the twister-drum shaft 75 by two independently-driven coaxial gears 97, 99. The machine is driven by an electric motor and the shafts are linked for timing by chaindrives. The sprocket-wheels on the shafts carrying the forming-drums are angularlyadjustable to enable the mesh-wires to be brought into coincidence on the twister drum. The finished netting is stripped by a roll 43 which carries teeth to engage the mesh. The forming and twister drums and the wire-seating and stripping rolls are each so constructed as to enable individual components to be removed when worn or damaged. The staples 55 are longer than the longitudinal stretches in the finished fabric to allow slack for the twisting operation. The amount of slack may be adjusted by a nut 63, Fig. 4, which alters the positions of the fixed staples. The degree of twist in the wire can be adjusted by half a turn by altering the order of deposition of the wires in the twister-gear slots. In a modified machine, a single forming drum is used, alternate wires being led over a guide before being seated on the twister drum in correct position to form the mesh with the other wires which are led directly to the drum. For producing " straight line " netting also, (see Group I), only one forming drum is necessary. If graduated mesh-width netting is required, the staples 55, the gears 89, and the wires fed to the forming drums are suitably spaced. If the range of width is considerable, the fine-mesh wires are fed to the drums after the movement of the staples has begun. The Specification as open to inspection under Sect. 91 refers to U.S.A. Specification 2,204,602, which describes the production of netting of graduated mesh-width. This reference does not appear in the Specification as accepted.