GB2310962A

GB2310962A - Shieding a terminal block

Info

Publication number: GB2310962A
Application number: GB9703228A
Authority: GB
Inventors: Jacques Barral; Alain Imberlin
Original assignee: Pouyet SA
Current assignee: Pouyet SA
Priority date: 1996-03-06
Filing date: 1997-02-17
Publication date: 1997-09-10
Anticipated expiration: 2017-02-17
Also published as: GB2310962B; GB9703228D0; FR2745971A1; DE29703912U1; FR2745971B1

Description

The present invention relates to a terminal block for connecting telephone- or computer-related lines.

Modern telephone or computer installations must be designed for outputs which are increasingly higher and therefore for frequencies which are likewise increasingly higher.

Applicants' document EP-A-0 524 115 describes a terminal block which ensures earth continuity.

In particular, this terminal block comprises one or more earth combs, or toothed semi-grids which ensure earth continuity with one or more patch cords, themselves each provided with an earth wire or drain, and possibly a metallized strip forming a shield which surrounds the pairs that this patch cord contains.

This type of terminal block of the known prior art presents two drawbacks: such a terminal block is not really perfectly shielded.

It is therefore sensitive to the surrounding electromagnetic disturbances, which is not admissible for high outputs and frequencies; the two earth continuity combs, or the single comb, are fragile and delicate to place in position.

It is an object of the present invention to overcome these drawbacks.

To that end, it relates to a terminal block for connecting telephone or computer lines, this terminal block comprising, to the rear, an earth bar intended to receive the stripped shielding of one or more telephone or computer cables to be connected on the terminal block by the rear, and being characterized: - in that it comprises, at least on its two large faces, a conducting cap which is connected to earth and which comprises an upper conducting cover on one of its two large faces and a lower conducting cover on the other large face, - in that at least one of these two covers is metallic and comprises, in one piece and forming its front part, an earth comb comprising prominent teeth adapted to receive a conjugate part, connected to earth, of a patch cord fitted on this terminal block.

Advantageously, only one of these two covers is such a toothed cover which covers one of the two large faces, while the other cover, which covers the opposite large face, is a conventional cover with wire-guide channels, made of plastics material but coated, at least on one side, with at least one metallization layer.

The invention will be more readily understood on reading the following description with reference to the accompanying drawings, in which: Figure 1 is an exploded rear view in perspective of this terminal block.

Figure 2 is an overall view, in perspective, of this same terminal block in position on a metallic receiving frame.

Figure 3 is a view, in longitudinal section at the level of a tooth of one of its two earth combs, of this same terminal block with a patch cord connected in the plane of section.

Referring now to all of Figures 1 to 3, the terminal block is of the so-called "rear-wired" type. Consequently it comprises a conventional transverse metal earth bar 1 which is disposed at the rear of the terminal block and on which will be fixed, by collars passing in couples of bores 2, 3 provided to that end, the two multi-pair cables (here two four-pair cables) which bear the incoming lines. So as to ensure earth continuity and shielding, the strip or the metal shielding braid of these cables is previously stripped and turned at its free end and it is this portion of shielded end which is taken in each collar and therefore pressed against the earth bar 1.

This terminal block is conventionally designed to be received on a metal U frame 4. The earth bar 1 consequently comprises elastic end ears 5 which, when the terminal block is fitted well on the frame 4, come into elastic abutment against this frame, thus establishing the earth connection therewith.

The principal body 6 of the terminal block, of which the front part 7 comprises the two parallel, upper and lower rows 8 and 9 respectively, of insulation displacing metal contacts, further receives: On its lower large face 10: - a conventional earth comb 12 whose teeth 13 receive, when a patch cord 14 is fitted on the front part 7 of the terminal block, one of the branches 15 of an earth contact 16 which equips the connecting plug of this patch cord. To be placed in position, this earth comb is conventionally applied against the lower face 10 of the principal plastic body 6 of the terminal block.

- a cover 17 with wire-guide channels 18 and with a conventional lateral output. This cover 17 is conventionally fixed on the terminal block by clips 19. It is made of plastics material but, in accordance with the present invention, it is metallized on its inner face which comprises the wire-guide channels 18. This cover 17 serves, inter alia, as mechanical member for holding the metal earth comb 12 against the lower large face 10 of the body 6 of the terminal block. Level with this comb 12, there are provided, on the lamellae which form the walls of the wire-guide channels 18, metallized contact terminals 20 which ensure a reliable, positive earth connection contact between the comb 12 and the metallized part of the cover 17. Finally, two metallized lateral tabs 21, which are parallel and substantially coplanar with respect to the vertical clips 19, rise upwardly and rub, in order to establish an earth continuity connection, against two conjugate tabs 22 of a metal cover 23 which, in accordance with the invention, covers the other large face of the body 6 and which will be described in greater detail hereinafter. this metal cover 23, which comprises no wire-guide channel, contrary to the metallized plastic cover 17, and which covers the other large face 11 of the body 6 of the terminal block. In accordance with a characteristic of the invention, the front part of this metal cover 23 forms, in monolithic manner, an earth comb 24 whose protuberant teeth are respectively coplanar (in the vertical and longitudinal plane) and parallel to the respective conjugate teeth 13 of the lower comb 12. These teeth of the upper comb 24 are each made to receive the other branch 25 of the "U contact 16 which equips the plug for connedting a patch cord 14. The metal cover 23 comprises, on its rear edge 26 and likewise in monolithic manner, elastic contact tabs 27 which are directed downwardly and which rub against two conjugate metal tabs 28, which are provided on the front edge 29 of the earth bar 1 and which are directed upwardly, thus connecting the metal cover 23 to this earth bar 1 and therefore ensuring earth continuity of the assembly 1, 17, 12, 23 which constitutes the virtually complete electromagnetic shielding of this terminal block.

It will be noted with interest that the terminal block which has just been described is multi-purpose. In fact, it may be used either for transmitting high outputs, of 10 to 100 Megabits or even more, and therefore high frequencies, and, in that case, patch cords such as cord 14 must be used, or, on the contrary, for transmitting much lower frequencies, typically of traditional analog telephony, in which case the wire-guide channels 18 may be used for passing ordinary telephonic pairs, or jumpers, in order to be connected for example either towards a subscriber's line or towards another terminal block for lowfrequency analog telephony.

It goes without saying that the invention is not limited to the embodiment which has just been described. For example, this terminal block may further be equipped, on its two small lateral faces, with metallized label-holders which are also in earth connection, for example via the metal cover 23 with which they are in electrical contact.

Claims

CLAIMS 1. A terminal block for connecting telephone or computer lines, this terminal block comprising, to the rear, an earth bar intended to receive the stripped shielding of one or more telephone or computer cables to be connected on the terminal block by the rear, wherein: - it comprises, at least on its two large faces, a conducting cap which is connected to earth and which comprises an upper conducting cover on one of its two large faces and a lower conducting cover on the other large face, - at least one of these two covers is metallic and comprises, in one piece and forming its front part, an earth comb comprising prominent teeth adapted to receive a conjugate part, connected to earth, of a patch cord fitted on this terminal block.
2. A terminal block as claimed in Claim 1, wherein only one of these two covers is such a toothed cover which covers one of the two large faces, while the other cover, which covers the opposite large face, is a cover with wire-guide channels, made of plastics material but coated, at least on one side, with at least one metallization layer.
3. A terminal block as claimed in Claim 2, wherein this metallized cover with wire-guide channels is in mechanical and electrical contact with a metal earth comb which is applied against said opposite large face and whose teeth are respectively parallel, and coplanar in the vertical plane, to those of the comb which is integrated in the metal cover which covers the other large face.