Patent GB-1314489-A (GB)
Title: Storage battery grid wound from wire and process or making same
IPC: D04H3/00
Filed: 1971-09-02
Abstract: 1314489 Making batteries; angular bending GENERAL MOTORS CORP 2 Sept 1971 [8 Sept 1970] 40974/71 Headings B3A and B3E [Also in Division H1] A storage battery grid 2 comprises a lug 6 on one edge of the grid, conductive wires 4 diverging from the lug and thermoplastic coated reinforcing filaments 8a, 8b crossing and forming an integral composite with the wires, the lug comprising a nest of loops formed in the wires 4. The grids are made in a strip 2 on a machine 15, Fig. 3, which has grid-forming blocks 18, circulating in a track 16. At the start position, Fig. 3, or stage A, Fig. 6, an empty block 18 enters under a plate 35 with pilot pins 22 all but touching the plate. Filaments 8a are fed on to the blocks and between the pins 22 in stage B and as the block advances to stage C camming means drive a gathering pin 24 gathering the filaments in its path to the bottom of the block. A first row of wires 4 is laid between the uppermost pins 22 at stage D and as the block advances to stage E another camming means drives the pin 24 upwardly thereby returning the filaments 8a to their original position and gathering the wires 4 to the top of the block, where they are lightly gripped by jaws 30. The pin 24 is cammed toward the bottom of the block 18 at stage F and a lower row of wires 4 is laid between the remaining pins 22, stage G. As the block advances to stage H the pin is again cammed upwardly, returning the filaments and gathering the lower wires between the jaws 30. At stage I a layer of filaments 8b is laid on top of the wires 4 and camming means at state J closes the jaws 30 to form a neck 7 in the nested wire loops. The blocks 18 then pass beneath an infra-red oven 36, Fig. 3, and beneath a press 38 which embeds the heated wires 4 in the thermoplastic coating of the filaments. In one form of press, Fig. 5 (not shown), the blocks pass under a stainless steel belt (40) and an anvil (42), which depresses the pins 22, 24 into the blocks, and the belt applies pressure on the filaments and wires. The belt moves at the same linear velocity as the blocks. The grid strip 2 is either coiled or trimmed and treated as required. In an alternative form of machine 51, Fig. 8, modified blocks 57 move separately through a curve 68 of a track 52, which has a cover-plate (not shown) under which the blocks pass and pins 58, 60, 64 on the blocks are spaced immediately below the plates to prevent the wires slipping off the pins. As the blocks enter the curve, camming means (not shown) depresses the pin 60 and as the blocks move round the curve, the wires bunch up and collect between the depressed pin 60 and a pin 64. The pin 60 is released at this point thereby trapping the wires between the pins 60, 64, and each block is brought into aligned contiguous relation with the preceding block 57. As the blocks pivot into alignment, a second pin 64 completes the looping of the wires and partly crimps them to form a neck (74) in the lug (72), Fig. 9 (not shown). Only one layer of filaments is fed from spools 78 and the heated grid is pressed by a plurality of shaped platens engaging each block at the bonding stage. The platens have holes which mate with the pins on the blocks. The wires may be of lead alloy and are preferably knurled to improve bonding to the coated filaments, which are preferably of glass fibre covered with a hot melt type thermoplastic coating having a polyethylene base.