Patent GB-1480883-A (GB)
Title: Chassis for supporting electronic equipment
IPC: H05K7/18
Filed: 1975-06-30
Abstract: 1480883 Printed circuit assemblies FRANCE MINISTRY OF POST & TELECOMMUNICATIONS and SOC SOCOTEL 30 June 1975 [8 July 1974] 27498/75 Heading H1R A chassis carrying electronic equipment comprising plug-in, e.g. printed circuit boards is erected (Fig. 1) with uprights 1, 2 fixed respectively between identical and symmetrical base-plates and corresponding top plates constructed from U-shaped angles 8 fixed to short arms 9, 10 projecting from cross-members 4, 7. Other projecting arms 11, 12 are similarly connected by cross-members. Upright 1 is profiled to define vertical posts 13, 14 connected by web 15; post 13 being of parallelepipedal cross-section of which inward face 16 has a cruciform groove 17 retaining brackets 18, 19 supporting individual chassis cells. Front face 20 of the post has cruciform grooves 21, 22 and a slot 23. Post 14 is similarly formed with grooves 24, 25, 26 and slot 27. Upright 2 is identical and symmetrical with upright 1; comprising posts 28, 33 with grooves 29, 30, 31 and slot 32 and slot 34 and similar grooves; respectively. Brackets 35, 36, 37 and 38, 39, 40 fit grooves 29, 34; respective pairs of brackets, e.g. 35, 38 correspondingly defining the positions of the top of one cell and the bottom of another cell of the assembly. Bracket 36 identical with other brackets 18, 19, 35, 37, 38, 39, 40 comprises (Figs. 2, 3, 4, not shown) a box member in which a beam 41 connected by screws to right angled beam 44 may slide, the box member having a lug which enters one of a series of spaced holes in a slide resting in the rearmost extension of the cruciform groove 29 and being retained by a rotatory rectangular plate engaging the lateral extensions of the groove; retention being assisted by resilience of the metal. Transverse beams 44, 60 connecting slide bars 41, 45 support adjacent grooved plates 61, 62, 63, 64 forming the floor of a cell whose roof is formed by similar grooved plates 65, 66 &c. hooked to beams similar to 44, 60 mounted on slides similar to 41, 45 bracketed at 37, 40, 19. Above these are located the floor plates of another cell supported by the beams from which plates 65, 66 &c. are suspended. A circuit board 67 is inserted for example between corresponding grooves of plates 62, 66. In Figs. 5, 6, 7 slide-bars 41, 45; beams 44, 60; grooved plates 61 to 64 flooring an upper cell and grooved plates 68 to 71 roofing a lower cell are shown; the plates being plastic moulded and the grooves being interrupted by ventilating openings 72. Beams 44, 60 have projecting ribs 74 engaging connector supporting frame member 75, with vertical faces having upper projecting rib 76 fitting a slide-bar 77 of plate 64 and a lower projecting rib 78 fitting a slide-bar 79 of plate 71. Beam 44 is centrally grooved in the upper face to receive a bar 82 having regularly spaced holes in one of which a projection 83 of plate 64 is engaged for location. A similar groove in the lower face receives a convex leaf spring 86 pressing plates 68 to 71 to maintain retention of the circuit boards therebetween. The beams 44, 60 are secured to slide-bars 41, 45 by selftap screws, e.g. 87 passing through holes of the slide-bars to engage the ends of grooves 81, 83. Spring stops 90, 91 screwed to the slide-bar 41 have extended tongues 92 rotatable to engage the supporting brackets after assembly. A connector supporting frame (Fig. 8) comprises an upright 93 with an upper supporting cross-member 94 and a lower supporting crossmember 95, in which are superimposed a supporting cross-member 75 and upright 96 of the next upper cell. Upright 96 is of L-section with one leg enlarged at 97 to define a strut with a cruciform groove 98 receiving vertical feed cables. The remaining leg is drilled for screws 99 engaging a slide 100 in the cruciform groove 101 of post 33 of upright 2 which is symmetrical with respect to groove 30 thereof. Slide-bar 41 engages a notch of cross-bar 75 for location. Lower cross-bars, e.g. 75, 95 are grooved at 103 at the front edges to engage rib 74 of the corresponding beam, while groove 104, 105 enable the cross-bars to be fixed to the frame uprights by selftap screws engaging the grooves. Other grooves 106 of the cross-bars receive feed cables and a vertical 107 supports board connectors 107, 108 fixed thereto and notches of groove 103 engage locating projections of bars 77. An intermediate cross-bar 112 is mounted between cross-bars 94, 95 having wings 107 supporting corridors 108, 109; with grooves 115, 116 for attachment to uprights 93 by selftap screws. An inner groove receives feed cables. Uprights 117 (Fig. 1) interconnected by horizontal straps 18 support cladding panels 119 and are grooved for fixture to supporting straps 123 and to retain conventional boards. Modified uprights 1, 2 with plural grooves may be used (Fig. 10, not shown).