GB832618A - Contact assembly for electric plugboards - Google Patents

Abstract

832,618. Two-part couplings; plug boards. AMP Inc. Feb. 10, 1956 [Feb. 10, 1955], No. 4266/56. Class 38 (1). In a plug-board assembly wherein a plugboard carrying pins is loosely pivoted to a fixed plug-board carrying blade contacts and the two sets of contacts are engaged by first swinging the boards together, so that the contacts overlap, and then moving the pivoted board along the fixed board, the blade contacts 19, Fig. 5, according to one construction each have an end portion 35 twisted through 45 degrees and formed with a transverse V-shaped ridge 37, one leg of which is longer than the other. The pin, during its contact-engaging movement transversely of the blade, first engages the end of the longer leg of the ridge 37, subsequent movement causing the blade to be deflected sideways and the ridge to wipe over a section of the pin. When the shorter limb of the ridge is engaged by the pin the point of contact moves back along the wiped portion of the pin to a position approximately in the centre thereof, the pin then lying adjacent the edge of the blade. The other end of the blade carries a socket 31, which receives a plug 33 on a lead 18, and the contact is mounted in an aperture in the fixed plug board by inserting the socket therethrough until shoulders 25 on the end of the blade engage a groove in one face of the board, whereupon wings 29 on an extension 27 of the socket 31 are spread into engagement with the other face of the board. In the modification shown in Fig. 9, the rib 43 is in the form of a ramp which increases in height from the leading edge 43a whereby deflection of the blade 41 is effected without twisting the end as in the previous embodiment. Alternatively, Fig. 12, the leading edge only of the rib 45 may be in the form of a short, steep ramp so that full deflection of the blade is obtained as soon as the pin commences to traverse the blade. Fig. 13 shows a simplified construction wherein the contact rib 49 is formed by bending over the end of the blade 53. A locking effect may be obtained as shown in Fig. 15 by tapering the shorter leg 55b of rib 55 oppositely 'to the leg 55a, but not to the same extent, so that increased contact pressure is necessary to disengage the contacts. Another construction is shown in Fig. 17 wherein a straight rib 59 in the form of a ramp extends diagonally across the blade 61 whilst in Fig. 18 a'similar effect is obtained with a contact bent up from wire 63 and having an inclined ramp portion 67. Specification 796,333 is referred to.