GB1234480A - - Google Patents

Abstract

1,234,480. Distributing frames. F. TRUCCO. 13 Dec., 1968 [18 Dec., 1967], No. 59430/68. Heading H1L. [Also in Division H2] A connector element 20 comprises an insulating housing, which may be of plastics material, adapted to be assembled face to face with other similar elements to form a telephone exchange distribution frame and includes a diaphragm 22 carried by walls 24 which extend from both faces of the diaphragm to form tray-like cavities. The contact ends 34, 36, 42a, 44a of conductor strips 42, 44 preferably of phosphorbronze, extend through the walls and are fixed to them by means of upset studs 26 and passages 32. The conductor strips 42, 44 are mounted in the housing in two series (only one of which is shown in the drawing), one either side of the diaphragm 22 so that the ends 34, 36 form opposed contact pairs adapted to accept the pins of a plug connector. A cover 50, also of plastics material, is fitted over the contacts by means of studs 52 locating in recesses 54 asymmetrically disposed to orientate the cover correctly. Apertures 58, 60 in the cover allow the insertion of the plug pins. The element 20 further incorporates a metal earthing contact plate 62 fitted in the housing by upset studs 21 and formed with a comb edge depending from one end 66 and cylindrical contact members 64 at the other which receive the pins 70 of a plug 72. A stack of the elements 20 in face to face relationship is held by a C-shaped metal clip locating in grooves 27 and makes contact with the metal comb adjacent edge 66 of the plate 62 to provide an earth connection (74, 74b, Fig. 1, not shown). A pair of metal rods, one of which is earthed via a metal end cover, locate in the grooves 56. The contact ends 42a, 44a are connected to telephone subscriber line-pairs whilst a plug inserted into the socket formed by contacts 34, 36 connects with other exchange equipment through an over-current thermal protection device incorporated in the plug (84, Figs. 9-13, not shown). The protection device against overcurrents includes a rocker member urged by a spring blade retained by the pin of a current-carrying heat coil so that when the current exceeds a certain value the pin blows out, freeing the spring and allowing the rocker member to close an earthing circuit and operate an alarm system. The plug 72 houses a vacuum spark-gap lightning protector to shield the circuits from overvoltages. In other embodiments no provision is made for protection against overvoltage and the plate 62 with contacts 64 and plug 72 are omitted.