GB1594534A

GB1594534A - Telecommunications terminal strip

Info

Publication number: GB1594534A
Application number: GB8756/78A
Authority: GB
Original assignee: RUTENBECK E; SCHMIDT KG SCHIEDERWERK G; Krone GmbH
Current assignee: RUTENBECK E; SCHMIDT KG SCHIEDERWERK G; ADC GmbH
Priority date: 1977-03-12
Filing date: 1978-03-06
Publication date: 1981-07-30
Also published as: SE7802668L; NL184816B; SE424682B; NL184816C; AT365860B; NL7802094A; ATA175178A; FR2383533A1; DE2710973A1; DE2710973C2; FR2383533B1

Description

(54) TELECOMMUNICATIONS TERMINAL STRIP (71) We, KRONE GmbH, of Goerzallee 311, 1000 Berlin 37, Germany (Fed. Rep.); a German body corporate; EMIL RUTENBECK t/a DR. FRANZ & RUTENBECK of Klagebach 31-37, 5885 Schalksmuehle, Germany (Fed. Rep.); a German, and SCHIEDERWERK GUENTER SCHMIDT KG FABRIK FUER APPARATE DER FERNMELDE UND ELECrR-OTECHNIK, of Solgerstrasse 21, 8500 Nuernberg, Germany (Fed. Rep;); a German company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to a telecommunications terminal strip having a detachable overvoltage protection device, in which the terminal strip contains a plurality of connecting terminal assemblies arranged parallel to one another, and an earth terminal and the overvoltage protection device contains a voltage protector per connecting terminal assembly. The connecting terminal assemblies each have a terminal for an incoming lead and an outgoing lead. The earth terminal and the connecting terminal assemblies each have a contact tongue projecting from the terminal strip and acting as a test lug and as plug junction for the overvoltage protection device.

Such terminal strips are used predominantly for connecting and distributing telecommunication cables in surface-mounted and concealed boxes and in-weatherproof surface-mounted housings.

Overvoltave protection devices are generally used, but only when there are special overvoltage risks.

In a known device of this type the contact tongues of the connecting terminals acting as test lugs and as attachable connections for the overvoltage protection device are located centrally between the terminal contacts for the incoming or outgoing leads and the attachable overvolt protection device is so formed that the voltage arresters and the associated contact springs are located laterally of the terminal strips.

This arrangement has the disadvantage that the space requirement for the whole apparatus, more especially the required base surface is considerable since the central tongues necessitate relatively wide terminal strips and the lateral voltage protectors require considerable space in width. The lateral positioning of the voltage arresters is unfavourable inasmuch as the corresponding parts of the over-voltage protection device project into the connection spaces of the terminal strips and occupy these to such an extent that very little space remains for the connecting leads connected to the connecting terminals.

During the operation of the overvoltage protection device this involves the leads being sharply bent and which are thereby in danger of fracture. The necessary bending of the leads is moreover possible only when these have been connected with suitable spare length. If this is not the case, a time consuming resetting of the leads or the cables concerned is necessary. In the known apparatus moveover, it is of disadvantage that for connecting the contact tongues of the connecting terminals with the contact springs for the voltage protector, located with relatively large lateral spacing, long electrical bridges are necessary and the contact tongues, also acting as testing lugs, are so close together that only small tapping terminals may be attached.

The object of the invention is to provide a terminal strip, of the type described, provided with a detachable over-voltage protection device which avoids the disadvantages described of known apparatus and requires as little as possible installation space.

According to the present invention there is provided a telecommunications terminal strip with a detachable overvoltage protection device, in which the terminal strip comprises an earth connecting terminal and a plurality of connecting terminal assemblies arranged in parallel to one another and spaced apart from one another, said connecting terminal assemblies each having a pair of terminals one of said terminals for an incoming lead and the other of said terminals for an outgoing lead, the overvoltage protection device including an overvoltage protector for each terminal assembly, and the connecting terminal assemblies and the earth terminal are each provided with a contact tongue projecting from the terminal strip and acting as a test lug and as a plug connection contact which connecting terminal assembly contact is mateable with a respective contact spring engaged with a respective overvoltage protector in the overvoltage protection device, wherein the terminals for the incoming leads and the terminals for the outgoing leads are arranged in two parallel rows with each row having the contact tongues extending from alternate terminals so that the contact tongues in the two rows are staggered relative to each other, and wherein the contact springs are arranged in a corresponding pattern to enable the contact tongues to be plugged into the contact springs.

The advantages obtain & d with this arrangement consist especially in that the terminal strip in accordance with the invention is much narrower than that of known devices and also that the overvoltage protection device requires no greater space, in width, than the terminal strip, so that when using several or a plurality of these terminal strips in boxes or housings whether with or without an overvoltage protection device, a relatively close juxtaposition arrangement is permitted and hence a particularly effective space utilisation. A further advantage in the arrangement in accordance with the invention is that the overvoltage protection device does not make contact with the leads connected to the terminals and the lower contact springs for the overvoltage protectors are in direct contact with the contact tongues of the connecting terminals, thus saving special electrical. conductor bridges. Further, the contact tongues acting as test lugs of the connecting terminal assemblies, due to their alternate arrangement, are spaced sufficiently apart that even the largest conventional tapping terminals may be applied thereon.

Preferably, the contact tongue of. the earth connecting terminal which is located at one end of the terminal strip, is arranged on the vertical medial line of the terminal strip and the overvoltage protection device has corresponding resilient opposite contact on both ends. The advantage of this is that the overvoltage protection device may be plugged into the terminal strip not only in a specific position, but also turned through 180 degrees, so that when being plugged-in no special care is needed.

The contact springs for the overvoltage protectors are preferably adapted as threearmed crown contacts. This feature, in combination with the alternate arrangement of the contact springs, permits such a spacesaving grouping of the overvoltage protectors that the connecting terminals (formed by standard screw members) of the connecting terminal assemblies may be arranged with very small spacing. The attachable overvoltage protection device hence has no influence on the size of the terminal strip which was hitherto not possible to obtain with four-armed crown contacts conventional in cylindrical overvoltage protectors owing to the minimum spacing to be maintained therebetween. The three-armed contact springs moreover are mechanically and electrically more favourable than the known four-armed ones.

Moreover, the invention preferably provides for the contact springs for the overvoltage protectors to be located proximate the contact tongues of the connecting terminals and to be connected thereto via lateral spring arms of the contact springs. This ensures that the plug connections for the overvoltage protection device do not affect the overall height of the overvoltage protection device, so that the latter is substantially determined only by the length of the overvoltage protectors and hence may be of minimum possible dimension. The open space required in front of the terminal strip for the overvoltage protection device is correspondingly small.

A further advantageous feature of the invention consists in that the overvoltage protection device has inner and outer insulating parts between which the lower contact springs for the overvoltage protectors are mounted. This attains a particularly favourable mounting, from a manufacturing point of view, of the lower contact springs, since these are simply inserted in the compartments of the inner insulating part saving in special securing preparations and positionally secured by plugging over the outer insulating part.

The outer insulating part of the overvoltage protection device may have apertures which act as vents for the interior space defined by the inner insulating part, the outer insulating part and the earth terminal strip. These measures avoid heat accumulation with thermal loading of the overvoltage arresters in the case of operation in the overvoltage protection device.

The outer insulating part and the earth strip of the overvoltage protection device may have handling projections formed thereon. This facilitates pulling the overvoltage protection device off the terminal strip and the pulling of the earth strip out of the insulating parts of the overvoltage protection device without the use of any tools.

The present invention will be' described further by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a plan view of a terminal strip; Fig. 2 is a plan view, partly in section, of an attachable overvoltage protection device; Fig. 3 is a section of the terminal strip taken on the line I-I of Fig. 1; Fig. 4 is a section through the overvoltage protection device taken on the line Il-Il of Fig. 2; Fig. 5 is a section through the terminal strip taken on the line Ill-Ill of Fig. 1; and Fig. 6 is a section through the overvoltage protection device taken on the line IV-IV in Fig. 2.

A terminal strip 1 (Figs. 1, 3 and 5) consists of an insulating body having an outer part 2 and an inner part 3, in which a plurality of connecting terminal assemblies 4 and an earth terminal 5 are mounted. The connecting terminal assemblies 4 each have a pair of terminals, i.e. a connecting terminal 6 for an incoming lead and a connecting terminal 7 for the outgoing lead.

Each terminal assembly 4 consists of a connecting member 8, two terminal plates 9 and two screws 10 and each assembly 4 has a contact tongue 11, projecting from the terminal strip 1, and mounted at one end of the connecting member 8. The members 8 of adjacent terminal assemblies 4 are arranged in the terminal strip 1 so that the contact tongues 11 are alternately associated with the connecting terminals 6 or 7. The earth terminal 5 consists of a contact member 12, a terminal clamping plate 13 and a screw 14 is located at one end of the terminal strip 1 and has a contact tongue 16 mounted on the contact member 12 and aligned with the centre line 15 of the terminal strip 1. Mounting extensions 17 are provided on the terminal strip 1. The inner part 3 of the insulating body is inserted in the outer part 2 of the insulating body and retained therein by stop hooks 18.

An overvoltage protection device 19 (Figs. 2, 4 and 6) attachable to the terminal strip 1, is comprised of two insulating parts 20 and 21, between which contact springs 22 for overvoltage protectors 23 are mounted.

An earth terminal strip 24 is inserted in the insulating parts 20 and 21 which terminal strip 24 has tapping contacts 25 secured thereon. The springs 22 and the tapping contacts 25 are adapted as three-armed crown contacts, and the contact springs 22 each have laterial spring arm 26 by means of which they are connectable to the contact tongues 11 of the connecting terminal assemblies 4. The tapping contacts 25 are secured by rivet flanges 27 to the earth terminal strip 24. The earth strip 24 has a counter contact 28 at each end for connection with the contact tongue 16 of the earth terminal 5 located in the terminal strip 1. The outer insulating part 21 has vent holes 29 in its lateral walls and at the front lateral edges of the insulating part 21, beadshaped projections 30 are provided which act as gripping ledges during the pulling of the overvoltage protection device 19 from the terminal strip 1. The earth strip 24 has projections 31 forming handles for facilitating pulling the earth strip 24 out of the insulating parts 20 and 21. The outer insulating part 21 extends over the inner insulating part 20 and detachably secured thereto by stop cams 32.

WHAT WE CLAIM IS: 1. A telecommunications terminal strip with a detachable overvoltage protection device, in which the terminal strip comprises an earth connecting terminal and a plurality of connecting terminal assemblies arranged in parallel to one another and spaced apart from one another, said connecting terminal assemblies each having a pair of terminals one of said terminals for an incoming lead and the other of said terminals for an outgoing lead, the overvoltage protection device including an overvoltage protector for each terminal assembly, and the connecting terminal assemblies and the earth terminal are each provided with a contact tongue projecting from the terminal strip and acting as a test lug and as a plug connection contact which connecting terminal assembly contact is mateable with a respective contact spring engaged with a respective overvoltage protector in the overvoltage protection device, wherein the terminals for the incoming leads and the terminals for the outgoing leads are arranged in two parallel rows with each row having the contact tongues extending from alternate terminals so that the contact tongues in the two rows are staggered relative to each other and wherein the contact springs are arranged in a corresponding pattern to enable the contact tongues to be plugged into the contact springs.

2. A telecommunications terminal strip with a detachable overvoltage protection device according to Claim 1, in which the contact tongue of the earth connecting

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. operation in the overvoltage protection device. The outer insulating part and the earth strip of the overvoltage protection device may have handling projections formed thereon. This facilitates pulling the overvoltage protection device off the terminal strip and the pulling of the earth strip out of the insulating parts of the overvoltage protection device without the use of any tools. The present invention will be' described further by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a plan view of a terminal strip; Fig. 2 is a plan view, partly in section, of an attachable overvoltage protection device; Fig. 3 is a section of the terminal strip taken on the line I-I of Fig. 1; Fig. 4 is a section through the overvoltage protection device taken on the line Il-Il of Fig. 2; Fig. 5 is a section through the terminal strip taken on the line Ill-Ill of Fig. 1; and Fig. 6 is a section through the overvoltage protection device taken on the line IV-IV in Fig. 2. A terminal strip 1 (Figs. 1, 3 and 5) consists of an insulating body having an outer part 2 and an inner part 3, in which a plurality of connecting terminal assemblies 4 and an earth terminal 5 are mounted. The connecting terminal assemblies 4 each have a pair of terminals, i.e. a connecting terminal 6 for an incoming lead and a connecting terminal 7 for the outgoing lead. Each terminal assembly 4 consists of a connecting member 8, two terminal plates 9 and two screws 10 and each assembly 4 has a contact tongue 11, projecting from the terminal strip 1, and mounted at one end of the connecting member 8. The members 8 of adjacent terminal assemblies 4 are arranged in the terminal strip 1 so that the contact tongues 11 are alternately associated with the connecting terminals 6 or 7. The earth terminal 5 consists of a contact member 12, a terminal clamping plate 13 and a screw 14 is located at one end of the terminal strip 1 and has a contact tongue 16 mounted on the contact member 12 and aligned with the centre line 15 of the terminal strip 1. Mounting extensions 17 are provided on the terminal strip 1. The inner part 3 of the insulating body is inserted in the outer part 2 of the insulating body and retained therein by stop hooks 18. An overvoltage protection device 19 (Figs. 2, 4 and 6) attachable to the terminal strip 1, is comprised of two insulating parts 20 and 21, between which contact springs 22 for overvoltage protectors 23 are mounted. An earth terminal strip 24 is inserted in the insulating parts 20 and 21 which terminal strip 24 has tapping contacts 25 secured thereon. The springs 22 and the tapping contacts 25 are adapted as three-armed crown contacts, and the contact springs 22 each have laterial spring arm 26 by means of which they are connectable to the contact tongues 11 of the connecting terminal assemblies 4. The tapping contacts 25 are secured by rivet flanges 27 to the earth terminal strip 24. The earth strip 24 has a counter contact 28 at each end for connection with the contact tongue 16 of the earth terminal 5 located in the terminal strip 1. The outer insulating part 21 has vent holes 29 in its lateral walls and at the front lateral edges of the insulating part 21, beadshaped projections 30 are provided which act as gripping ledges during the pulling of the overvoltage protection device 19 from the terminal strip 1. The earth strip 24 has projections 31 forming handles for facilitating pulling the earth strip 24 out of the insulating parts 20 and 21. The outer insulating part 21 extends over the inner insulating part 20 and detachably secured thereto by stop cams 32. WHAT WE CLAIM IS:

1. A telecommunications terminal strip with a detachable overvoltage protection device, in which the terminal strip comprises an earth connecting terminal and a plurality of connecting terminal assemblies arranged in parallel to one another and spaced apart from one another, said connecting terminal assemblies each having a pair of terminals one of said terminals for an incoming lead and the other of said terminals for an outgoing lead, the overvoltage protection device including an overvoltage protector for each terminal assembly, and the connecting terminal assemblies and the earth terminal are each provided with a contact tongue projecting from the terminal strip and acting as a test lug and as a plug connection contact which connecting terminal assembly contact is mateable with a respective contact spring engaged with a respective overvoltage protector in the overvoltage protection device, wherein the terminals for the incoming leads and the terminals for the outgoing leads are arranged in two parallel rows with each row having the contact tongues extending from alternate terminals so that the contact tongues in the two rows are staggered relative to each other and wherein the contact springs are arranged in a corresponding pattern to enable the contact tongues to be plugged into the contact springs.

terminal which is located at one end of the terminal strip is arranged on the central line of the terminal strip and the overvoltage protection device has a corresponding opposite contact at each end.

3. A telecommunications terminal strip with a detachable overvoltage protection device according to Claim 1 or 2 in which the contact springs for the over voltage protectors are formed as three-armed crown' contacts.

4. A telecommunications terminal strip with a detachable overvoltage protection device according to any of the preceding claims, in which the contact springs for the overvoltage protectors, with the overvoltage protection device attached, are located adjacent to the inside surfaces of the contact tongues of the connecting terminal assemblies and connected therewith via lateral spring arms of the contact springs.

5. A telecommunications terminal strip with a detachable overvoltage protection device according to one or more of any of the preceding claims in which the overvoltage protection device has internal and external insulating parts between which the contact springs for the overvoltage protectors are mounted.

6. A telecommunications terminal strip with a detachable overvoltage protection device according to one or more of any of the preceding claims, in which the external insulating part of the overvoltage protection device has apertures for the ventilation of the interior space defined by the internal insulating part the external insulating part and an earth terminal strip.

7. A telecommunications terminal strip with a detachable overvoltage protection device according to Claim 6, in which the external insulating part and the earth terminal strip of the overvoltage protection device are provided with handling projections.

8. A telecommunications terminal strip with a detachable overvoltage protection device substantially as herein described with reference to and as illustrated in the accompanying drawings.