| 摘要 |
1,264,701. Making nozzles; welding by pressure; shearing; upsetting. OWENS-CORNING FIBERGLAS CORP. 1 May, 1969 [29 May, 1968], No. 22241/69. Headings B3A, B3H, B3R and B3W. [Also in Division C1] Apparatus for making an extrusion nozzle 14 of an orificed stream feeder comprises a shearing station 20 where tubular stock 23 is cut into short lengths and deforming stations 24, 30, 32 where the lengths are shaped. The stock 23 is platinum or platinum alloy and is fed through a stationary block 35 at the first station into a bore of a lower movable block 37. The bore has a spring 46 which ejects the cut of length. The lower block is moved by a pneumatic motor or a cam (not further described) to shear the stock and the cut-off length is transferred to the next station 24. The dies 51, 53 at the second station shorten the length of stock 26, Figs. 3 and 4 (not shown). The stock is transferred to the next station 30 for further upsetting. Figs. 5 and 6 (not shown). The end of the shaped stock is coined at the fourth station 32 by a coming pin 106 which co-operates with the dies 91, 93 at this station. The dies 91, 93 are the same shape as the dies at the previous station and the pin 106 shapes the bore of the stock and smooths the end. The upper dies 51, 71, 91 are moved by press rams and the lower dies 53, 73, 93 have ejector pins 67, 87, 107 operated by cams. The coining pin 106 forms part of the ejector pin at the final station. The coining station may be omitted and the nozzle end smoothed by grinding. The head 120 of the nozzle 14 has an annular ridge 124 approaching a knife edge which is welded to a base plate 16 of the stream feeder. The passageway 128 has an outward taper 127 at the head end which expands inwards during the welding. The nozzles 14 are positioned on the base plate 16 by a jig 135, Fig. 10 (not shown), with ceramic pins 137 which extend through the orifices 18 in the base plate. The base plate 16 is made of platinum or platinum alloy and the jig 135 of conductive material. The jig 135 acts as one electrode and a second electrode 150 is abutted with the head 120 of the nozzle for resistance welding. During welding the nozzle head expands on to the pin 137, Fig. 13 (not shown). In an alternative embodiment of welding apparatus, Fig. 14 (not shown), the upper electrode (160) has a pin (170) on to which the head expands. The nozzle 14 is held in the electrode by a suction pump. The welding may be performed without the pins 137, (170). |
