GB1560168A

GB1560168A - Electrical terminal block

Info

Publication number: GB1560168A
Application number: GB5205177A
Authority: GB
Original assignee: CA Weidmueller GmbH and Co
Current assignee: Weidmueller Interface GmbH and Co KG
Priority date: 1976-12-16
Filing date: 1977-12-14
Publication date: 1980-01-30
Also published as: DE7639373U1

Description

(54) ELECTRICAL TERMINAL BLOCK (71) We, C. A. WEIDMijLLER K. G.

of 175 Paderborner Strasse, 4930 Detmold 14, West Germany, a Germany 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: This invention relates to electrical terminal blocks, in particular electrical terminal blocks of the kind comprising an electrically insulating housing of generally slab-like form, in which are mounted electrical terminals. By "generally slab-like form", we mean that the housing has a pair of parallel major side faces, and intervening narrow sides. The terminals are accessible at one or more of the narrow sides and the terminal blocks are mounted face to face with one another so as to form a terminal assembly. Such terminal blocks have become widely known and used, since they enable a large number and a wide variety of circuit connections to be made in a small space.

British Patent Specification No. 1,387,554 discloses an electrical terminal block incorporating in a common housing a feedthrough terminal pair (i.e. a pair of interconnected terminals each adapted to connect a wire, flex or cable), and a second terminal pair including a terminal which is a clamp arranged to grip a bus-bar. This enables the terminal block to be used both to make a power connection, and to make an earth or neutral connection. In many circumstances, it is necessary also to make a connection to a protective conductor, for example to provide both earth and neutral connections. This can be done by means of a separate terminal block, but this is inconvenient and requires the provision of two different types of terminal block each including mounting means, in particular a mounting foot for fixing on a supporting rail with oppositely directed flanges. An object of the present invention is to provide a simple construction in which the desired additional connection can be made within a single terminal block.

The present invention resides in an electrical terminal block comprising a generally slab-like insulating housing, a mounting foot for mounting the terminal block transversely on a channel-section support rail with oppositely directed flanges, and three mutually insulated pairs of interconnected terminals in the housing, two said terminal pairs being disposed one above the other (with respect to the mounting foot), one of the said two pairs being a feed-through terminal pair and the other of the said two pairs including a terminal adapted to clamp, in use, a busbar extending transversely to the major side faces of the housing, and the third terminal pair being disposed alongside (in a direction transverse to the major side faces of the housing) one of the said two terminal pairs.

We have thus provided a terminal block in which all three of the required connections can be made and which forms a constructional unit requiring only a single mounting foot, and is therefore economical to produce and easy to install and remove.

The housing may be a single integral member common to all of the terminals.

Alternatively the block may be an assembly of two initially separate housing members of which one contains the said two pairs and the other contains the third pair. These two housing members can be united securely in any convenient way, for example by welding, by means of an adhesive, or by mechanical interlocking, possibly further secured by an adhesive. In this case, only one of the individual housing members need be provided with a mounting foot.

Two embodiments of the invention are shown in the accompanying drawings, in which; Figure 1 is a side view of a first terminal block embodying the invention, mounted on a supporting rail, Figure 2 shows the terminal block of Figure 1, seen at right angles to the supporting rail, and Figures 3 and 4 are views corresponding to Figures 1 and 2 of a second terminal block embodying the invention.

Figures 1 and 2 show a rail-mounted terminal block consisting of a first terminal unit 1 which is a "stacked" arrangement generally similar to that disclosed in British Patent Specification No. 1,387,554, and a second unit 5. Each of these units has an insulating plastics housing member of the generally slab-like form well known in this field, whereby a plurality of terminal blocks can be mounted side by side in a relatively small space.

The terminal units 1 and 5 are secured side by side to form a single terminal block as can be seen in Figure 2, in particular by welding together the abutting faces of the housing members of the individual units, or by means of an adhesive. Alternatively, a single integral housing for both units may be provided.

The first unit 1 has in its upper region, (i.e.

the region further from the mounting rail 8) a feed-through terminal pair comprising screw-clamping terminal sleeves 2 and an inter-connecting metal bar, accessible through opposite narrow sides of the unit. In the lower region, between the feed-through terminal pair and the rail 8, is a second terminal pair consisting of a screw-clamping terminal (not visible in the drawing; at the right in Figure 1) connected by a metal bar to a clamp 3 comprising a pair of jaws 10 which, in the position shown, project from one narrow side of the housing so that they can clamp between them a bus-bar 4 extending past the terminal block parallel to the rail 8.

The clamp is provided with a clamping screw and also embraces the bar connected to the screw-clamping terminal so that the latter can be connected to the bus-bar. By loosening the screw of the clamp, the jaws can be retracted into the insulating housing clear of the bus-bar.

The second unit 5 incorporates a further pair of screw-clamping terminals 6 interconnected by a metal bar which is integral with a metal clamping foot 7 which clamps the flanges of the rail 8 to support the entire terminal block. The terminals 6 are thereby electrically connected to the rail 8. Like the terminals 2 and the that terminal of the busbar connection that is not visible in the drawing the terminals 6 are accessible through respective narrow sides of the terminal block.

As can be seen in Figure 2, the unit 1 has no means for mounting on the rail 8; the complete terminal block is supported only by the clamp 7.

In the embodiment shown in Figures 3 and 4, the first terminal unit 1' is generally similar to the unit 1 shown in Figures 1 and 2, except that the feed-through terminals 2' are arranged for access through the uppermost narrow face, instead of through opposite faces. The second unit 5' again has a screwclamping terminal 6 accessible through a narrow side face, but this is connected by a metal bar to a second screw-clamping terminal 6' accessible from above for connection of a protective conductor; there is no connection to the rail 8.

The terminal block as a whole is supported by a single common clip-on foot 7'. As shown in Figure 4, the individual housings of the units 1' and 5' are inter-connected by pins 9 mating with sockets, these pins being secured by an adhesive.

In the illustrated embodiments, the respective feet are adapted for mounting on rails of the standard asymmetrical crosssection with inwardly turned flanges; the invention is equally applicable to terminal blocks with feet for mounting on the standard rails with symmetrical cross-section and outwardly turned flanges.

The terminal block shown in Figures 1 and 2 has, effectively, three terminal pairs, including the clamping foot which provides a conductive connection to the support rail which in turn can be connected for example to an earthing point. It would be possible to omit one of the screw-clamping terminals 6 and that part of the metal bar carrying it, so that the remaining screw clamping terminal 6 and the clamping foot 7 constitute a pair of earthing terminals.

WHAT WE CLAIM IS: 1. An electrical terminal block comprising a generally slab-like insulating housing, a mounting foot for mounting the terminal block transversely on a channel-section support rail with oppositely directed flanges, and three mutually insulated pairs of interconnected terminals in the housing, two said terminal pairs being disposed one above the other (with respect to the mounting foot), one of the said two pairs being a feedthrough terminal pair and the other of the said two pairs including a terminal adapted to clamp, in use, a busbar extending transversely to the major side faces of the housing, and the third terminal pair being disposed alongside (in a direction transverse to the major side faces of the housing) one of the said two terminal pairs.

2. A terminal block as claimed in claim 1 in which the terminal pair including the said busbar clamping terminal is closer to the mounting foot than is the said one terminal pair.

3. A terminal block as claimed in claim 1 or 2 in which the third terminal pair incorpo

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. a supporting rail, Figure 2 shows the terminal block of Figure 1, seen at right angles to the supporting rail, and Figures 3 and 4 are views corresponding to Figures 1 and 2 of a second terminal block embodying the invention. Figures 1 and 2 show a rail-mounted terminal block consisting of a first terminal unit 1 which is a "stacked" arrangement generally similar to that disclosed in British Patent Specification No. 1,387,554, and a second unit 5. Each of these units has an insulating plastics housing member of the generally slab-like form well known in this field, whereby a plurality of terminal blocks can be mounted side by side in a relatively small space. The terminal units 1 and 5 are secured side by side to form a single terminal block as can be seen in Figure 2, in particular by welding together the abutting faces of the housing members of the individual units, or by means of an adhesive. Alternatively, a single integral housing for both units may be provided. The first unit 1 has in its upper region, (i.e. the region further from the mounting rail 8) a feed-through terminal pair comprising screw-clamping terminal sleeves 2 and an inter-connecting metal bar, accessible through opposite narrow sides of the unit. In the lower region, between the feed-through terminal pair and the rail 8, is a second terminal pair consisting of a screw-clamping terminal (not visible in the drawing; at the right in Figure 1) connected by a metal bar to a clamp 3 comprising a pair of jaws 10 which, in the position shown, project from one narrow side of the housing so that they can clamp between them a bus-bar 4 extending past the terminal block parallel to the rail 8. The clamp is provided with a clamping screw and also embraces the bar connected to the screw-clamping terminal so that the latter can be connected to the bus-bar. By loosening the screw of the clamp, the jaws can be retracted into the insulating housing clear of the bus-bar. The second unit 5 incorporates a further pair of screw-clamping terminals 6 interconnected by a metal bar which is integral with a metal clamping foot 7 which clamps the flanges of the rail 8 to support the entire terminal block. The terminals 6 are thereby electrically connected to the rail 8. Like the terminals 2 and the that terminal of the busbar connection that is not visible in the drawing the terminals 6 are accessible through respective narrow sides of the terminal block. As can be seen in Figure 2, the unit 1 has no means for mounting on the rail 8; the complete terminal block is supported only by the clamp 7. In the embodiment shown in Figures 3 and 4, the first terminal unit 1' is generally similar to the unit 1 shown in Figures 1 and 2, except that the feed-through terminals 2' are arranged for access through the uppermost narrow face, instead of through opposite faces. The second unit 5' again has a screwclamping terminal 6 accessible through a narrow side face, but this is connected by a metal bar to a second screw-clamping terminal 6' accessible from above for connection of a protective conductor; there is no connection to the rail 8. The terminal block as a whole is supported by a single common clip-on foot 7'. As shown in Figure 4, the individual housings of the units 1' and 5' are inter-connected by pins 9 mating with sockets, these pins being secured by an adhesive. In the illustrated embodiments, the respective feet are adapted for mounting on rails of the standard asymmetrical crosssection with inwardly turned flanges; the invention is equally applicable to terminal blocks with feet for mounting on the standard rails with symmetrical cross-section and outwardly turned flanges. The terminal block shown in Figures 1 and 2 has, effectively, three terminal pairs, including the clamping foot which provides a conductive connection to the support rail which in turn can be connected for example to an earthing point. It would be possible to omit one of the screw-clamping terminals 6 and that part of the metal bar carrying it, so that the remaining screw clamping terminal 6 and the clamping foot 7 constitute a pair of earthing terminals. WHAT WE CLAIM IS:

1. An electrical terminal block comprising a generally slab-like insulating housing, a mounting foot for mounting the terminal block transversely on a channel-section support rail with oppositely directed flanges, and three mutually insulated pairs of interconnected terminals in the housing, two said terminal pairs being disposed one above the other (with respect to the mounting foot), one of the said two pairs being a feedthrough terminal pair and the other of the said two pairs including a terminal adapted to clamp, in use, a busbar extending transversely to the major side faces of the housing, and the third terminal pair being disposed alongside (in a direction transverse to the major side faces of the housing) one of the said two terminal pairs.

rates a metal clamp constituting the mounting foot whereby in use the third terminal pair is electrically connected to the support rail.

4. A terminal block as claimed in claim 1 or 2 in which the third terminal pair is a feed-through terminal pair.

5. A terminal block as claimed in any of claims 1 to 4 in which the said two pairs are disposed in a first housing member and the third pair is in a second housing member, the two housing members being fastened together side by side to form the said housing.

6. A terminal block according to claim 5 characterised in that the housing members are welded together.

7. A terminal block according to claim 5, characterised in that the housing members are adhesively joined together.

8. A terminal block according to claim 5, characterised in that the housing members are pinned together.

9. A terminal block according to claim 8 characterised in that the pin connections of the two housing members are adhesively secured.

10. A terminal block as claimed in any of claims 1 to 4 in which all three said pairs are disposed in a single common housing member.

11. An electrical terminal block substantially as herein described with reference to Figures 1 and 2 or Figures 3 and 4 of the accompanying drawings.