| 摘要 |
1,216,215. Welding by pressure. INTERNATIONAL BUSINESS MACHINES CORP. 4 Nov., 1968 [11 Dec., 1967], No. 52178/68. Heading B3R. [Also in Divisions H1 and H2] In a multilayer printed circuit assembly (see Division H1) electrical connections from one of the circuit layers 28 to 42 to one surface 44 of the assembly is accomplished by resistance welding a wire 54 to 62, passing through an aperture leading to the layer, to the layer. A plurality of conductive planes 28 to 42 interleaved with insulating layers 12 to 26 are arranged in a stack 10, the layers and planes being provided with aligned apertures in accordance with the connections to be made. An insertion-welding apparatus 200 is moved along X, Y co-ordinates by lead screws, Fig. 5 (not shown), until wire 210 from a spool 22 is positioned over a desired aperture and then a signal from programmer, 244 is sent on line 246 to energize motor 218 which drives associated cam 220 into engagement ment with cam follower 221 on lever 222. As cam 220 rotates towards its low point spring 227 pivots lever 222 about shaft 226 so that its head 224 moves downwards towards assembly 10 and the wire 210 is inserted into the desired aperture as the spool 212 rotates. At this time the welder 256 with short test circuitry 246 is continuously monitoring the resistance between wire 210 and the conductive planes to which no connection is desired. If a short is indicated the apparatus is stopped. When the wire 210 reaches the desired conductive plane and contact is made a stop feed signal is generated by circuitry 250 and passed to the programmer 244 to stop motor 218. A signal is then sent to welder circuitry 256 which generates a current pulse on line 258 leading to leaf springs 260 which contact wire 210. This current pulse completes a circuit through the wire 210 and the plane contacted by that wire so as to effect a weld between the wire 210 and the particular conductive plane. Motor 218 is re-energized and cam 220 continues to rotate to its high point moving head 224 upwards the wire 210 slipping therethrough. Cam 220 contacts a switch 262 and motor 218 is stopped after which a signal is sent on line 264 to energize motor 232 and rotate cam to move blade 230 laterally in a direction opposite to spring 236. Cutting edges 228, 230 are brought into contact with each other to sever the wire 210. When cam 234 reaches switch 266 at its high point motor 232 is deenergized. The apparatus 200 is then moved to a second aperture and the process repeated. The conductive planes may be made of copper and the wire gold-plated copper. If the wire is insulated the shearing operation removes a certain amount of insulation from the wire to bare the lower surface of the next segment of wire. |
