Patent GB-1274332-A (GB)
Title: Electric part mounting apparatus
IPC: H05K13/04
Filed: 1969-08-05
Abstract: 1,274,332. Inserting components in circuit boards; angular bending; shearing; solenoid presses. MATSUSHITA ELECTRIC INDUSTRIAL CO. Ltd. 5 Aug., 1969 [10 Aug., 1968 (2); 19 March, 1969; 9 May, 1969], No. 39230/69. Headings B3A, B3E, B3H and B3W. An electric part mounting apparatus comprises a band of parts 5 having axially extending leads 5k joined by means of tapes 57, a storage drum 4, a cutter unit 6 for cutting the ends of the leads 5k while advancing the band and delivering the cut parts individually, a head unit for bending the leads of the parts and inserting them into holes formed in a printed substrate 88 after positioning the part, a conveyer unit for transporting the parts from the cutter unit to the head unit, and means for positioning the printed substrate. Inside an electric box 1 is located a control box la, a programme board 1b and a servo-amplifier 1c, the board 1b issuing electric signals for the performance of the various work steps. The cutter unit.-A solenoid 8, see Fig. 3, is actuated by a signal from the programme board 1b to drive a linkage 11, 13 and pawl 15 against the action of a spring 20, thereby rotating a ratchet 12 mounted on a shaft 14. Also mounted on the shaft are feed gears (7) and cutter wheels (7a), which respectively hold the outer and inner ends of the leads 5k, Fig. 2 (not shown). As the cutter wheels rotate, the lead ends protruding therefrom are sheared off by cutters 17, the cutting edges of which abut the wheels (7a) on their outer faces. The solenoid plunger 8a is returned by the spring 20 and rotation of the ratchet 12 is prevented by a pawl 21. The cut parts 5a drop between guides 18, 18a on to a conveyer guide belt 35 and the tapes with the severed lead ends are led away by guides 30. The conveyer unit.-The belt 35 runs between guides 37 and carries the parts 5a to a hopper 36, from whence they are fed by a hose 39 to the head unit. A support plate 38 prevents vibration of the belt. The head unit.-The hose 39 is connected to a part receiving member 41, see Fig. 5, and it delivers the part 5a to a space between die members 48, 53. The member 48 drives the part leftwardly and the leads are bent by engagement in slots 53a, see Fig. 8. A member 61 is driven downwardly, after the member 48 has been withdrawn, so that it abuts the member 53, pivots it about a pin 54 and then engages the part 5a to drive the leads 5k into holes in the substrate 88. The member 61 is slidable within a cylinder 56 and coupled for rotation therewith by a ball 64 engaging in a groove 61a. The top of the cylinder 56 is formed as a pinion 65 and engages a rack 66, which is reciprocated by a cylinder 69. A constantly rotating motor 74 drives a rod 73 which is coupled to an electro-magnetic clutch-brake 75. A signal from the programme board 1b corresponding to the desired direction of insertion of the part 5a is transmitted to one of a plurality of microswitches 79. Simultaneously the clutch 75 is engaged to rotate cams 77 via gears 76, 80, the latter of which is provided with stopper pins 78 of different lengths. When the selected switch 79 is opened by a cam 77, the gear 76 is disconnected from the drive and stopped. A selected pin 78 is then in the path of a stopper 84, thereby determining the length of stroke of the cylinder 69 and hence the degree of rotation of the pinion 65. At the lower extremity of the insertion stroke, the ball 64 is engaged in an annular groove 58a and a flange 56a of the cylinder 56 abuts the top of a stopper cylinder 43. The member 61 continues to move downwardly to move the part 5a out of the die 53 and on to the substrate 88. As the leads 5k pass through the holes in the substrate they are bent by an anvil to secure the part 5a. As the member 61 is withdrawn, the cylinder 56 remains fixed until the groove 61a comes level with the ball 64 and releases it from the annular groove 58a, whereupon a spring 42 drives the cylinder 56 upwardly. The printed substrate positioning unit.-The required holes in the substrate 88 are positioned under the head unit by means of servo-motors 102, 105 which rotate threaded rods 98, 104. The amounts of rotation are regulated by a voltage difference between position setting potentiometers (not shown) and position detecting potentiometrs 103, 106, the substrate being correctly positioned when the difference is zero. Precise positioning of the substrate is achieved by lowering a tapered pin 94 into a hole in a template 109. In an alternative embodiment a tapered pin (94<SP>1</SP>) engages the template from below, Figs. 16, 17 (not shown). The substrate mounting and dismounting unit, Fig. 19.-When the required number of parts 5a have been mounted on a substrate 88, the lowermost of a stack of substrates 88 is delivered from a hopper 142 by a runner 145 to below a notch 111a in a sliding plate 111. Cylinders 127a, 127b are actuated to rotate cam-shafts 132 of a pair of chuck units (the right hand unit is not shown) so that cams 133 pivot fingers 137 to open them. Then posts 114 are lowered thereby lowering the plate 111 and the cylinders 127a, 127b are again actuated to close the fingers 137 thereby gripping the substrate with the mounted parts and the other substrate from the hopper. The posts 114 are elevated, thereby removing the substrate from its positioning table 87, and the plate 111 is moved leftwardly so that the new substrate is located over the table 87. The posts are again lowered, the fingers 137 opened to release both substrates, then the posts are raised and the plate 111 returned to its original position to complete the work cycle.