EP0769825A2 - Connection terminal, in particular for connecting tapping conductors to main conductor and contact element therefor - Google Patents

Abstract

The feeder connector allows a branch cable to be connected to a main cable and has a fitting that is cylindrical in shape and this has a recess to receive a clamping element Ä25Ü This is shaped to install a contact element Ä39Ü that is of metal and has formed spikes Ä43Ü that are pressed into the metal strands of the main power cable. The inner profile is curved to match that of the cable. A strip sealing material is used Ä45Ü. The contact element has a hole Ä51Ü sized to suit the branch cable.

Description

The present invention relates to a connecting terminal, in particular for connecting branch conductors to main conductors of an earth line, according to the preamble of claim 1.

Furthermore, the present invention relates to a contact element for use in a clamping element of a connecting terminal, in particular for connecting at least one branch conductor to a main conductor.

Such terminals are used in particular for connecting a house connection to a main conductor buried in the ground. For this purpose, a branch conductor must be connected to the main conductor, the main conductor as such must not be interrupted, i. H. that a separation of the main conductor and interposition of a connecting piece for branching for the branch conductors is prohibited according to the relevant regulations.

For this reason, terminals have so far been developed which have at least two clamping elements which are attached to and enclose the main conductor. To the Generating an electrical contact between the insulated main conductor and a branch conductor, the insulation surrounding the multi-core main conductor is removed for the area of the connecting terminal, so that the cores of the multi-core main conductor which are in each case insulated are freely available. Corresponding contacts are provided to produce an electrical contact between the individual wires of the main conductor and the corresponding branch conductors, the clamping elements having to be clamped accordingly on the main conductor to produce the contact, which is done by means of a clamping device.

Conventionally, the connection terminal consists of two half-shell clamping elements, each with two contact elements, so that four branch conductors can be connected to four different wires of a main conductor.

The half-shell clamping elements provided for this purpose are correspondingly complex and the attachment is very complex, since a corresponding targeted penetration of separating elements between the cores of the multi-core main conductor and a supply to the contact elements is required.

In addition, the half-shells are each tightened to their contact surfaces by means of screws which have to be screwed through the end flanges of the half-shells.

A disadvantageous correspondingly long assembly time of such half-shell connection terminals is required.

Furthermore, three-part terminals are known, which have a contact element in each part, which has corresponding contacts for penetrating into the main conductor. The structural design, in particular of the end faces of the clamping elements coming into contact and their screwing together, corresponds to that of the half-shell connection terminals.

Furthermore, it is disadvantageous in the connection terminals or contact elements of the prior art that the position securing of the branch conductor in the connection terminal is carried out by means of clamping screws, which on the one hand requires increased assembly effort and on the other hand defined tightening torques have to be ensured so that the branch conductor (s) are defined and correctly clamped will.

This can be done conventionally with screws, in particular tear-off screws or the like, but these are particularly expensive as a component and require careful handling during assembly.

Furthermore, in the half-shell embodiment of a connecting terminal adapted for four-core cables of a main conductor, there is the disadvantage that it can only be used for four-core main conductors, and these must also have identical cross sections.

The present invention is therefore based on the object of improving a connecting terminal of the type mentioned in such a way that it can be used universally and in particular enables a particularly simple fixation of the branch conductor or conductors in the connection terminal.

Furthermore, it is an object of the present invention to provide a corresponding contact element which is suitable for use in a clamping element of a connecting terminal, in particular for connecting at least one branch conductor to a main conductor, and is therefore universally used.

The solution to these tasks results from the features of claims 1 and 27, respectively.

According to the invention, the contact element of the connection terminal has at least one spring element which has a spring device which can be deformed by the branch conductor when it is inserted and which generates both a positional securing of the branch conductor and an electrical contact between the contact element and the branch conductor.

According to the invention, it is thus possible to simply secure the branch conductor in the corresponding opening of the contact element in order to secure it in the contact element, additional complicated screwing and jamming of the branch conductor being avoided by means of screws.

The spring element used in the connection terminal according to the invention is able to generate the position securing force required for the branch conductor, and in addition a good electrical contact due to the deformed Sections of the contact element and thus their contact with them is ensured.

The same advantages also result in the contact element according to the invention, with the additional advantage that it can be used universally in connection terminals and can be used for any type of connection terminals which are used in the electrical connection of two conductors.

In particular, this also includes multi-core conductors both as main conductors and as branch conductors.

Further advantages of the connecting terminal according to the invention or the contact element according to the invention result from the respective subclaims.

Advantageously, the contact element arranged in the connection terminal has at least two, preferably three, spring elements which are essentially of identical design and are arranged at a small distance from one another in the opening of the contact element, the spring elements forming a set. This ensures that a corresponding secure mounting of the branch conductor is guaranteed in the opening and in addition a safe contact point for the transmission of the electrical current is also created.

It is also advantageous that a correspondingly simpler preassembly takes place by forming a set of spring elements.

If the contact element has at least two spring elements which are suitable for branch conductors of different cross-sectional dimensions, the contact element and thus the connecting terminal can be used universally. For example, different diameters allow branch conductors of different diameters to be held by one embodiment of a connecting terminal.

Furthermore, a plurality of sets of spring elements can also be arranged at a distance in the opening of the contact element, each set of spring elements being provided for a predetermined cross-section or a predetermined cross-sectional size of the branch conductor. Thus, the advantages of the universal applicability of the connection terminal are combined with the advantage of good daily security and contact connection.

With an annular design of the spring elements, a particularly simple and space-saving embodiment of the spring elements is created, which in turn supports the particular advantage of the small size of the entire connection terminal.

Furthermore, the annular spring element is advantageously designed such that notches extending from the inner edge of the annular spring element are provided, which extend in the direction of the outer edge of the spring element, one of the spring devices being formed between two adjacent notches.

With the aid of these spring tongues, it is advantageously achieved that when the branch conductor is inserted, its surface is scratched or torn open and the oxide layer located thereon is destroyed, for example in the case of aluminum conductors. This therefore leads to the safe generation of an electrical contact connection.

An even greater compactness of the connecting terminal is advantageously achieved in that the contact element has two openings for receiving two branch conductors. Thus, two branch lines for two different houses can be created with one connecting terminal.

In this case, the axes of the openings can coincide, the axis or the axes advantageously also running or running parallel to the axis of the main conductor in the connecting terminal.

It is of course possible to arrange the openings differently, for example perpendicularly or obliquely to the axis of the main conductor which crosses the connecting terminal.

If a partition is provided between the openings, this advantageously serves as a stop for the branch conductor when it is inserted into the opening.

The same or similar also applies to the different spring elements or sets of spring elements set out above, the openings of the spring elements for example Taper towards the stop of the opening or partition. This means that the smallest branch conductor is picked up by the innermost spring element and the largest branch conductor is picked up by the spring element that is closest to the inlet opening.

The contact element advantageously has tooth-shaped contacts on the side facing the main conductor, the tips of which serve for engagement with the main conductor.

This is done in such a way that the teeth penetrate into the insulating jacket of the respective wire or wire of the multi-core main conductor and then come into contact with the wire or wires of the main conductor.

The teeth are advantageously arranged side by side in several rows.

In a particularly simple embodiment, the contact element can be sleeve-shaped.

Terminals, especially those that are laid underground, must be permanently protected against the ingress of dirt and moisture so that the electrical connection is permanently secured. For this reason, the clamping element has at least one cavity opening inwards towards the main conductor for receiving a contact element. It is thus advantageously achieved that the contact element is completely sealed off from the outside of the connection terminal, and thus penetration of moisture and dirt can be reliably prevented.

The connecting terminal is advantageously composed of a plurality of clamping elements, which are sector-shaped for this purpose.

Depending on the type of executive, appropriate sectors are formed. Thus, in the case of a four-core main conductor which has essentially four cores of the same size, a connecting terminal with four clamping elements is formed, which can be identical in their design. This in turn advantageously results in a simplification in the manufacture of the clamping elements.

However, main conductors are also increasingly being used which have different cores in their size. For example, a main conductor is used in which three cores are sector-shaped with an angle of greater than 90 ° and a fourth core as a neutral conductor is in the remaining fourth sector, which core can also be present as a round wire, for example.

The clamping elements are formed accordingly, i. H. three clamping elements with larger sector dimensions and one clamping element with a smaller sector are used.

The clamping elements are advantageously designed in the shape of a circular segment (FIGS. 3 and 5).

In the case of four clamping elements of the same size, an arc sector angle α of 90 ° degrees per clamping element is obtained.

In a so-called three-and-a-half-core main conductor, three clamping elements with a corresponding sector angle α are formed and the fourth, smaller clamping element has a correspondingly smaller sector angle.

For further sealing of the electrical connection points of the contact element or clamping element and main conductor, a sealing compound, preferably in the form of a sealing tape (FIGS. 3 to 5) is provided, which extends between the inner circumferential side of the contact element and the main conductor.

Correspondingly, the opening of the contact element into which the branch conductor is inserted can also be sealed off from the outside.

To stiffen the clamping element on the one hand and to save material on the clamping element on the other hand, this is designed as a rib-like body provided with recesses accessible from the outside. This achieves the sufficient strength of the clamping element when it is pressed against the main conductor on the one hand and when pressed against the adjacent clamping elements on the other.

Advantageously, the clamping element has a wedge projecting in the direction of the main conductor, which makes it possible for the wedge to be inserted between two wires of the main conductor when the clamping element is being attached, thus achieving a first mounting of the loose clamping element on the main conductor.

The wedge is advantageously divided into two spaced-apart partial wedges which are advantageously arranged in axial end regions of the clamping element, so that a corresponding free space is provided in between for the introduction of the contact element into the clamping element.

Again, in particular for reasons of sealing, the clamping element has one, preferably two, cross-sectionally tapering regions, which extend in opposite directions in the axial direction, these regions extending from the end faces of the clamping element.

The projection areas can advantageously be formed in one piece with the clamping element, so that the clamping element can be produced, for example, as an injection molded part.

The clamping device for clamping the clamping elements to one another and to the main conductor is preferably designed as a pipe clamp which can be placed around the clamping elements in a simple manner.

The pipe clamp can be designed in the form of a band and have a screw-shaped tightening element which applies a corresponding tightening torque to the clamping elements by screwing.

To also have a clearly defined tightening torque and thus a clearly defined clamping force of the connection terminal on To produce the main conductor, the screw of the helical tightening element is designed as a tear-off head screw. When a corresponding tightening torque is reached, the head of this screw tears off, which also supports a particularly simple and safe assembly of the connection terminal.

The present invention further relates to a contact element for use in a clamping element of a connecting terminal, in particular for connecting at least one branch conductor to a main conductor. For this purpose, the contact element has at least one opening for inserting the branch conductor and contacts for producing the electrical connection between the main conductor and the at least one branch conductor. According to the invention, the contact element has at least one spring element into which the branch conductor can be inserted and can thus be secured in position. In addition, a corresponding electrical contact is ensured by this spring element.

As already explained above, the contact element can furthermore have a plurality of spring elements or one or more sets of different or the same spring elements.

• Figur 1 eine perspektivische Ansicht einer an einem Hauptleiter montierten Erfindungsgemäßen Anschlußklemme;
• Figur 2 eine teilweise aufgebrochene Teilansicht eines Klemmelements der erfindungsgemäßen Anschlußklemme;
• Figur 3 eine Schnittansicht gemäß der Linie III-III von Figur 2;
• Figur 4 eine Seitenansicht auf das Klemmelement der erfindungsgemäßen Anschlußklemme, in einer verkleinerten Darstellung;
• Figur 5 eine Seitenansicht eines Kontaktelements;
• Figur 6 eine Schnittansicht gemäß der Linie VI-VI von Figur 5 des Kontaktelements; und
• Figur 7 eine Draufsicht auf ein Federelement des Kontaktelements.

Further details, features and advantages of the present invention result from the following description of preferred exemplary embodiments of the connecting terminal according to the invention or of the contact element according to the invention with reference to the drawings. It shows:

• Figure 1 is a perspective view of an inventive terminal mounted on a main conductor;
• Figure 2 is a partially broken away partial view of a clamping element of the terminal according to the invention;
• Figure 3 is a sectional view taken along the line III-III of Figure 2;
• Figure 4 is a side view of the clamping element of the terminal according to the invention, in a reduced view;
• Figure 5 is a side view of a contact element;
• Figure 6 is a sectional view along the line VI-VI of Figure 5 of the contact element; and
• Figure 7 is a plan view of a spring element of the contact element.

The structure of the connecting terminal according to the invention is first described below with reference to the figures.

Figure 1 shows a perspective schematic representation of a terminal 1, which is arranged around a main conductor 3. The main conductor 3 has an insulating jacket 5 which surrounds a multi-core cable harness 7. In the present schematic example, the cable harness 7 comprises four wires.

The main conductor 3 is freed of its insulating jacket 5 in the area 9 of the connecting terminal, which leads to a narrowing of the diameter of the main conductor 3.

The area 9 is surrounded by the connecting terminal 1, which has four clamping elements 11, three of which can be seen in FIG.

For the sake of simplifying the drawing, only one clamping element 11 is shown, which is provided with openings 13, into each of which a branch conductor 15 is inserted. The other clamping elements 11 also have openings for the branch conductor 15.

The four sector-shaped clamping elements 11 are surrounded by a band-shaped pipe clamp 17 which has a screw-shaped tightening element 19.

In the assembled state of the connecting terminal shown in FIG. 1, a tear-off head screw 21 can be seen, in which the tear-off head has already been cut off and only a corresponding fracture surface 23 can be seen.

As can be seen in FIG. 1, the clamping elements 11 shown there have smooth outer surfaces, whereas, in an alternative embodiment according to FIG. 2, a clamping element 25 is shown which also has rib-shaped structures externally open recesses or cavities 27 is provided. Ribs 29 and 30 delimit these cavities 27.

As can also be seen from FIG. 2, the clamping element 25 has a cross-sectionally narrowing projection region 33 on its end face 31, the tapering running in the direction of the outside or in the axial direction of the clamping element 25.

Here, too, a rib structure is retained and the projection region 33 is connected in one piece to the clamping element 25.

The partially broken section A is described in connection with FIG. 6.

Figure 3 shows a sectional view along the line III-III of Figure 2. From this sectional view, the structure of the clamping element 25, which is identical to the structure of the clamping element 11 except for the outer contour, is clear. For the sake of clarity, the illustration of the spring elements is omitted here and is shown in FIG. 5.

A cavity 35 is formed in the clamping element 25, which is open from the inside 37 of the clamping element 25.

In this cavity 35, a contact element 39 is inserted, which is designed so that it follows the contour of the cavity 35 on the one hand and the inside 37 of the clamping element 25 on the other.

On the inside or underside 41 of the contact element 39 facing the main conductor, tooth-shaped contacts 43 are provided which taper towards the main conductor.

A band-shaped sealing compound 45 is also provided on the underside 41 of the contact element 39.

The clamping element 25 also has a wedge 47, which is used to secure the position of the clamping element 25 on the main conductor.

A clamping element 25 with two projection areas 33 is shown schematically in a reduced form in FIG. The clamping element 25 has two wedges 47, which are arranged on the respective end regions of the clamping element 25. In between there is a free space 49, which is used in particular to insert the contact element 39 into the cavity 35 of the clamping element 25 from below.

Again, the band-shaped sealing compound 45 can be seen and, when viewed in conjunction with FIG. 3, it results that the tooth-shaped contacts 43 are arranged in three rows of 4 teeth each.

Other configurations of the teeth themselves or of the arrangement are of course possible within the scope of the invention.

FIG. 5 is a view of an insulated contact element 39 according to the invention, as shown in FIG. 3 as a part inserted into the clamping element 25. From Figure 5 an end opening 51 can be seen, which is explained in more detail with reference to FIG. 6.

FIG. 6 shows a sectional view of the contact element 39 according to the invention along the line VI-VI from FIG. 5.

As can be seen from FIG. 6, the contact element 39 has a symmetrical design with two openings 51, the axes 53 and 54 of which coincide in this embodiment.

A partition 55 is formed between the openings 51 and can serve as a stop for a branch conductor.

To fix the branch conductor 15 in the opening 51 or 13 (FIG. 1), spring elements 57 are provided, one of which is shown in a top view in FIG.

As can be seen in FIG. 6, three sets 59 of spring elements 57 are arranged in each opening 51.

As can be seen from FIG. 7, the spring element 57 is ring-shaped, with notches 63 running from the inner edge 61 to the outer edge 65, which result in flexible spring devices in the form of tongues.

The functioning of the connecting terminal according to the invention or the contact element according to the invention will now be described below.

To attach the terminal to the main conductor, the insulating jacket 5 is first in the area 9 of the terminals 1 removed so that the insulated of the multi-core main conductor 3 are accessible from the outside.

A sector-shaped clamping element 11 or 25 after the other is inserted with the help of the wedge 47 between two wires of the main conductor 3 and is initially secured in position.

When all, in the example 4 clamping elements 11 are on the main conductor 3, the band-shaped pipe clamp 17 is placed around the clamping elements 11 and tightened by means of a tear-off head screw 21.

The tooth-shaped contacts 43 penetrate into the insulating jacket of each wire, cut through it and hit the actual metallic conductor of the corresponding wire.

After applying a predetermined torque, the tear-off head of the tear-off head screw 21 tears off and the connecting terminal 1 is firmly mounted on the main conductor 3.

Then the branch conductor 15 is inserted into the opening 13 or 51 and passes through one or more sets of spring elements 59. The spring tongues 67 deform and grind on the surface of the branch conductor 15 in such a way that the oxide layer thereon is severed and an electrical contact is made . At the same time, the spring devices 67 jam on the branch conductor and prevent it from being pulled out of the opening 51 or 13 against its direction of insertion. This will make both a safe electrical Contact or a secure electrical connection is created and a secure anchoring of the branch conductor 15 in the opening of the clamping element 11 or 25 is ensured.

The present invention is not limited to the described embodiments. Depending on the requirements, for example, more clamping elements can also be provided, for example in the case of main conductors with more than four wires. In the example shown, the contact element 39 has two openings 51. When using the connection terminal for only one branch, however, it is sufficient that only quasi half of the contact element 39 is provided, i. H. that only one opening 51 is provided.

Furthermore, the design and the number of rings 57 can also be designed to be correspondingly variable. For example, polygonal inner recesses of the rings could be provided, and the holding and contact effect of a spring element 57 may already be sufficient to hold the corresponding branch conductor securely in the contact element and to ensure the electrical connection.

This advantageously results in a particularly simple, space-saving and universally usable construction of a connecting terminal and a contact element therefor, which can be adapted for a wide variety of applications by easily executing minor structural changes.

Claims (27)

Terminal (1), in particular for connecting branch conductors to the main conductor of an earth line, with at least two clamping elements (11, 25) which can be attached to and enclose the main conductor (3), with at least one contact element (39), which in the assembled state produces an electrical contact between the main conductor (3) and the branch conductor (15), and has at least one opening (13, 51) for inserting the branch conductor (15), and at least one clamping device (17) which clamps the clamping elements (11, 25) to one another and to the main conductor (3) so that they can be secured in position, characterized in that the contact element (39) has at least one spring element (57) which has spring devices (67) which can be deformed when the branch conductor (15) is inserted, and which both secure the position of the branch conductor (15) and an electrical contact between the contact element (39) and the branch conductor (15). Terminal according to claim 1, characterized in that the contact element (39) has at least two, preferably three, spring elements (57), which are of essentially the same design and are in the opening (51) of the contact element (39 ) are arranged, forming a set (59). Terminal according to claim 1, characterized in that the contact element (39) has at least two spring elements (57) which are suitable for branch conductors of different cross-sectional dimensions. Terminal according to claim 2, characterized in that the contact element (39) has at least two, preferably three, spring element sets (59) at a distance from one another, each spring element set (59) being provided for a predetermined cross section or for a predetermined cross section size. Terminal according to one of claims 1 to 4, characterized in that the spring element (55) or the spring elements (57) are ring-shaped (Figure 7). Terminal according to claim 5, characterized in that from the inner edge (61) of the annular spring element (57) starting with notches (63) are provided, which extend in the direction of the outer edge (65) of the spring element (57), one of the spring devices (67) being formed between two adjacent notches (63). Terminal according to one of claims 1 to 6, characterized in that the contact element (39) has two openings (51) for receiving two branch lines. Terminal according to claim 7, characterized in that the axes (53, 54) of the openings (51) essentially coincide. Terminal according to claim 7 or 8, characterized in that a partition (55) is provided between the openings (51). Terminal according to one of claims 1 to 9, characterized in that the contact element (39) has tooth-shaped contacts (43), the tips of which serve for engagement with the main conductor (3). Terminal according to claim 10, characterized in that the tooth-shaped contacts (43) are formed in rows next to one another. Terminal according to one of claims 1 to 11, characterized in that the contact element (39) is sleeve-shaped. Terminal according to one of claims 1 to 12, characterized in that the clamping element (11, 25) has at least one cavity (35) opening inwards towards the main conductor for receiving a contact element (39). Terminal according to one of claims 1 to 13, characterized in that the clamping element (11, 25) is sector-shaped. Terminal according to one of Claims 1 to 14, characterized in that it has four clamping elements (11, 25) of identical design. Terminal according to one of claims 1 to 14, characterized in that it has three identical clamping elements and a different, preferably smaller clamping element. Terminal according to one of claims 1 to 16, characterized in that the clamping elements (11, 25) are designed in the form of a segment of a circular arc. Terminal according to one of Claims 1 to 17, characterized in that a sealing compound, preferably in the form of a sealing strip (45), is provided for sealing the contact point between the contact element (39) and the contact point between the contact element (39) and the main conductor (3) between the inside (41) of the contact element (39) and the main conductor (3) extends. Terminal according to one of claims 1 to 18, characterized in that the clamping element (25) is designed as a rib-like body provided with recesses (27) accessible from the outside. Terminal according to one of claims 1 to 19, characterized in that each clamping body has a wedge (47) projecting in the direction of the main line (3). Terminal according to claim 20, characterized in that the wedge (47) is divided into at least two spaced apart wedges (47). Terminal according to one of Claims 1 to 21, characterized in that the clamping element has one, preferably two, cross-sectionally tapering projection regions (33) which extend from the end faces of the clamping element (11, 25). Terminal according to claim 22, characterized in that the projection areas (33) are formed in one piece with the clamping element (25). Terminal according to one of claims 1 to 23, characterized in that the clamping device is designed in the form of a pipe clamp (17). Terminal according to claim 24, characterized in that the pipe clamp (17) is preferably designed in the form of a band and has a screw-shaped tightening element (19). Terminal according to claim 25, characterized in that the screw of the helical tightening element (19) is a tear-off head screw (21). Contact element for use in a clamping element (11, 25) of a connecting terminal (1), in particular for connecting at least one branch conductor (15) to a main conductor (3), with at least one opening (13, 51) for inserting the branch conductor (15) and with contacts (43) for producing the electrical connection between the main conductor (3) and the at least one branch conductor (15), characterized, that the contact element (39) has at least one spring element according to one of claims 2 to 6.

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