GB961990A - Guide strips for the guiding and holding in position of plug-in boards - Google Patents

Abstract

961,990. Plug-in printed circuit board assemblies. STANDARD TELEPHONES & CABLES Ltd. Feb. 27, 1961 [Feb. 27, 1960], No. 7111/61. Heading H1R. In a rack 1 carrying printed circuit boards the latter are supported by a number of guide bars 4 which are held in position between front and rear transversal bars 3, 3<SP>1</SP> and 2, 21 respectively of the rack framework by means of an extension 8 at one end of each guide bar cooperating with a notch or keyway 9 in the front transversal bars and at the other end by a pin and socket arrangement. The notches and keyways may take several forms, Figs. 2 to 7 (not shown), the simplest being a serrated extension which is pressed into a correspondingly designed notch in the front transversal bars. In order to limit lateral movement of the guide bars 4 an engaging arrangement 11 is incorporated in the front transversal bars and may take the form of a series of teeth arranged at the front of the bars 2, 2<SP>1</SP> between which projections 10 on the guide bars fit. In the embodiment of Fig. 5 the extension 8 is divided into two halves which engage recesses in a comb-like strip inserted in the keyway of the front transversal bars 2, 2<SP>1</SP>, thus eliminating the need for the projections 10 and arrangement 11. In the embodiment of Fig. 8, extensions 8f having moulded projection 10f fit into a plastic strip 22 containing keyway 9f as well as the engaging arrangement 11f, the front transversal bars 2, 2<SP>1</SP> being made of sheet metal and shaped as shown. Figs. 9, 10, 12 (not shown), and Fig. 11 illustrate the manner in which the rear ends of the guide bars 4 are attached to the rear transversal bars 3, 3<SP>1</SP>. In Fig. 11 a strip 26 having a number of equallyspaced holes 7 is inserted in a groove of the upper and lower rear transversal bars 3, 3<SP>1</SP> of the rack, the holes being threaded to receive the threaded extension 6<SP>1</SP> of pin 6, so that the printed circuit-board holder 27 provided with spring contact strip 28 is held firmly in position. The guide bar 4 is then pushed over the pin 6 so that the latter enters opening 5. In the embodiment of Fig. 12 the guide bars are provided with two pins which pass through holes in a flap of the printed circuit holder and a similar strip to that of Fig. 11. As shown in Fig. 13, printed circuit boards 24 slide into grooves 13 of the guide bars 4 and may be screened from each other by screen plate 25 inserted in groove 131.