GB637016A - Improvements in automatic riveting machines - Google Patents

Abstract

637,016. Combined riveting and drilling machines. SOC. NATIONALE DE CONSTRUCTIONS AERONAUTIQUES DU SUDEST. March 6, 1947, No. 6373. Convention date, June 27, 1946. [Classes 83 (iii) and 83 (iv)] A riveting-machine is provided with operating units for effecting either automatically in sequentially timed order or separately all the operations for placing a rivet, said units comprising devices for clamping the parts to be riveted, drilling the, rivet hole, coating said rivet hole, positioning a heated rivet in its hole, setting the rivet and unclamping the parts. Drilling.-A combined drilling and countersinking tool 11 is carried by a spindle 6 supported in a slidable bushing 9 and rotated by a pulley 15. The bushing 9 comprises a piston 24 slidable downwards in a bore in a case 17 under pressure of fluid entering from an inlet 127, oil contained in a recess 22 below the piston 24 being ejected through outlets 23 and 26. The outlet 23 is closed by the piston 24 during the latter part of its stroke and the speed of feed of the tool 11 is thereby reduced to that appropriate for drilling and countersinking, the sectional area of the outlet 26 being adjustable to vary the rate of feed. The upward movement of the tool is effected by the entry of pressure fluid through the orifices 23 and 26, discharge taking place through the outlet 127, two speeds again being obtained. An adjustable abutment 12 limits the stroke of the drill. Riveting; riveted joints.-The upper jaw comprises two presser foot members 54 arranged on either side of the tool 11 and each connected to a guided vertical shaft joined to a yoke piece and reciprocable by a piston. The rivet holes are coated with a liquid such as rubber solution, paint, or varnish, through a nozzle 150, Fig. 11, located opposite the rivet hole on a tubular member 67 connected at the ends with compressed air and coating fluid inlet pipes 68 and 69 respectively, and with lateral arms 151 pivoted on pins 152. The device is normally held in the position indicated in Fig. 8 by a spring 75 and after the drilling and countersinking operation it is rocked to bring the spray nozzle 150 opposite the hole, by the upward movement of the drilling spindle 6, a cam surface 70 on the bushing 9 engaging a roller 72 on a pivoted lever 71. The air inlet is automatically controlled through a cam and roller and the spray nozzle 150 forms a check valve which opens to the liquid supply when compressed air is admitted to the nozzle, so that coating liquid is supplied only at the appropriate position of the nozzle. The rivets 29 are positioned on the periphery of a disc 28 and held by springs 30, step by step rotation of the disc being obtained through the medium of a toothed wheel 180 and a pawl 181a actuated by a pusher 32 having a roller 33 adapted to engage a cam surface 31 on the forward movement of the base member referred to later. Rivets are conveyed in turn from the disc 28 by tongs 37 mounted on a support slidable within a pivotal body 42 rigid with a shaft 186 journalled in the case 5 and having mounted at one end a pinion 53 meshing with a pinion 52 secured to a shaft 187 upon which is also mounted a disc 51 controlled by an arm 188 of the base member whose forward movement rotates the disc 51 through an angle such that the pivotal body 42 is rotated through 180 degrees, the rivet 29 in the tongs 37 being thereby disposed opposite to the rivet hole, with the head uppermost. The tongs operate by the engagement of an abutment 44 on the bushing 9 during its downstroke with a nose 201 of a pusher 45 urged upwards by a spring 46. The downward movement of the pusher 45 engages its lower portion 48 with a roller 49 to push the slidable tong support forward so that the tongs engage a rivet 29. On upward movement of the bushing 9 and the pusher 45, the tong support is spring returned to the position indicated in Fig. 8, where the rivet may be electrically heated between electrodes 39 and 40. After rocking of the tong support as described above the rivet is driven into the hole by a pin 61, mounted between cheek portions mounted on the movable cylinder 56 of the base member and slidable relative thereto. The pin is urged upwards by a spring and is moved downwards during the latter part of the stroke of the movable cylinder 56 by the engagement of a cam surface 62 with the pin 61, the initial movement of the cylinder serving to rotate the tong support and the disc 28 as previously mentioned. The pin 61 also serves as a riveting knob during the clenching of the rivet. A latch 65 controlled by the spindle 6 prevents the base member advancing until the spindle is in its uppermost position. The riveting stand 4, Fig. 7, comprises a moulded body 77, Fig. 18, containing a cylinder 79 whose initial position may be adjusted by the screw 81 through a worm 215, and wheel 214. Within the cylinder 79 a clenching piston 83 is extended upwardly by a tubular portion 233 through which and the cylinder 79 extends transversely a cotter pin 85 on which is mounted the cylinder 226 of the lower jaw actuating jack, having a piston 88, the upper end of whose piston rod 227 carries side arms 228 and 92 forming the jaw, which may be angularly adjusted by rotation of the bushing 94. A riveting snap 234 is located between the side arms 228 and 92, secured to a carrier 93 secured to the tubular portion 233 of the piston 83. The stroke of the snap is adjusted independently of the lower jaw by means of a nut 95 which adjusts the position of the bushing 94 whose lower edge forms a stop for a shoulder 235 on the tubular position 233. The operating. sequence is controlled through hydraulic distributers controlled by cams on a motor driven shaft. Electric switching enables the machine to operate in a continuous cycle or a rivet-by-rivet operation, the machine stopping after the placing of each rivet. Specification 614,169 is referred to,