Patent GB-1343219-A (GB)
Title: Static converter system built-up from modules
IPC: H01L25/03
Filed: 1971-12-17
Abstract: 1343219 Converter construction BROWN BOVERI & CO Ltd 17 Dec 1971 [19 Dec 1970] 58809/81 Heading H2F [Also in Division H1] Housing modules are constructed of plastics material and have co-operating bored ribs on opposite faces such that the modules may be assembled together by fasteners passing through the aligned bores of aligned ribs. A module 1À01 (Fig. 1) has a pair of opposite side walls 1À02 each including two identical recesses 1À04 which may or may not be covered by a removable plate or knock-out section (not shown). Two ribs 1À06 and 1À07 of equal length are formed on each side wall 1À02 and 1À03 respectively. Ribs 1À06 are provided with bores 1À08 and 1À09 and ribs 1À07 with bores 1À10 and hexagonal recesses 1À11. A second pair of sides 1À12, identical to one another, define a ceiling and floor which contain recesses (not shown). The front of the module has side flanges 1À14, Fig. 2, with apertures 1À15 and a flange 1À16 with apertures 1À17 is provided for receiving and mounting a lid 1À18, Fig. 1. A rear wall 1À20, Fig. 1, comprises a floor and circumferential collar 1À22 with side flanges 1À23, such that the wall may be joined to the module by means of screw-fasteners 1À24 connecting the flanges 1À19 and 1À23. Apertures are provided in the floor of the rear wall to accommodate two contact sockets. Two housings may be coupled longitudinally by attaching the front flange 1À14 of one module to the rear flange 1À19 of another module, four contact sockets then being provided in the rear wall of the resultant assembly. A rack may be formed from these individual housing modules by stacking the appropriate number of modules side by side and aligning corresponding ribs such that screw-fasteners may be inserted from above through the bores 1À08 and 1À10 in the ribs and screwed into nuts inserted into the hexagonal recesses 1À11. The head of each screw-fastener is provided with a screw thread such that another screw-fastener may be screwed in from above to connect a second row of modules to the lower row. Spacer tubes are provided where ribs are missing on the outer surfaces of the resultant rack. Cooling air is ducted through the rack in parallel streams through the cavities between the housing modules and through the modules themselves. To prevent intermixing of the air streams the apertures in the side walls are covered by plates. Frames 1À42, Fig. 10, are provided in the rack in order to discharge cooling air from a housing member and to direct a fresh stream of cooling air from the gap 1À40 into a lower frame. Converter modules.-As shown in Fig. 11, a static converter comprises an insulating box 2À01, which may be closed by a lid 2À02 provided with two apertures 2À03, accomodates one or two fusible cut-outs 2À04 connected into the circuit by screw fasteners 2À05 and 2À06, the bottom 2À11 of the box being provided with two apertures 2À12 on which illuminated signal means 2À07 are mounted to indicate fuse defects. Further apertures are provided for power current connections. The four corners of the wall 2À14 are chamfered to a guide the converter module into the housing module. A combination of two heat sinks 2À20, 2À21 and a thyristor or diode 2À22 is mounted on the box 2À01. A further insulating box 2À30, screw-mounted on the second heat sink 2À21, accommodates a plug pin 2À23 such that a power current path extends through the plug pin 2À23, insulated by a tube 2À24, to a bridge 2À25, then through the fusible cut-out 2À04 to the heat sink 2À20 and from there to a plug pin 2À28, insulated by a tube 2À29, via heat sink 2À21. The space 2À35 between the floor 2À31 of the box 2À30 and the heat sink 2À21 accommodates non- inductive resistors, the remaining circuit elements being mounted in the space 2À37. A double module may be formed from two such converter modules for insertion into a double housing module.