Grounding clip

Abstract

The invention relates to an earthing clamp (1) with at least one channel (4, 5) arranged between a primary clamping part (2) and a secondary clamping part (3), which channel (4, 5) is formed by a primary groove (22, 23) in a primary clamping surface (21) of the primary clamping part (2) and at least one secondary groove (32, 33) in a secondary clamping surface (31, 34) of the secondary clamping part (3), wherein the primary clamping part (2) and the secondary clamping part (3) are pressed relative to each other by means of at least one central clamping screw (8) inserted into aligned screw receiving openings (27, 28) of the primary clamping part (2) and the secondary clamping part (3), wherein a central screw axis (8a) of the central clamping screw (8) is formed at an angle to a longitudinal channel axis (4a, 5a) of the channel (4, 5) and the central screw axis (8a) and the longitudinal axis of the channel (4a, 5a) - in the direction of a minimal transverse (t) of the central screw axis (8a) and the longitudinal axis of the channel (4a,5a) considered - essentially span an angle (α) of approximately 90°, and wherein the primary clamping part (2) and the secondary clamping part (3) are designed to force-fit a conductor (6, 7) in the channel (4a, 5a) between the primary channel (22, 23) and the secondary channel (32, 33). To achieve simple and safe operation in a confined space, it is provided that the primary clamping part (2) has at least one cable connection opening (26) for a connecting cable (10) in a lateral connection area (25), which is designed to insert a connecting cable (10) along a cable entry axis (26a).

Description

[0001] The invention relates to an earthing terminal with at least one channel arranged between a primary clamping part and a secondary clamping part, which channel is formed by a primary groove in a primary clamping surface of the primary clamping part and at least one secondary groove in a secondary clamping surface of the secondary clamping part, wherein the primary clamping part and the secondary clamping part can be pressed relative to one another by means of at least one central clamping screw inserted into aligned screw receiving openings of the primary clamping part and the secondary clamping part, wherein a central screw axis of the central clamping screw is formed skew to a channel longitudinal axis of the channel and the central screw axis and the channel longitudinal axis - viewed in the direction of a minimum transversal of the central screw axis and the channel longitudinal axis - essentially span an angle of approximately 90°, and wherein the primary clamping part and the secondary clamping part are formed,to hold a wire or cable in the channel between the primary channel and the secondary channel.

[0002] Grounding terminals are generally used to connect a part of an electrical system to a ground potential. Common grounding terminals establish a force-locking connection to a ground potential via clamping screws.

[0003] DE 85 05 564 U1 discloses a grounding terminal for connecting grounding straps with a central clamping screw on either side of two parallel cable ducts. The grounding terminal can be attached to a mounting component using the central clamping screw. No means of securing the position are provided, so unintentional twisting of the grounding terminal cannot be ruled out. Connection of connecting cables is not provided.

[0004] US Pat. No. 8,864,504 B1 discloses a grounding clamp that is clamped onto a pipe or rod. Cables can be fixed to the grounding clamp parallel to the pipe or rod using clamping screws.

[0005] Especially in cable support systems, easy and safe operation and accessibility of the cable clamp screws of the grounding clamp are not always guaranteed. Connecting cables sometimes have to be routed in 90° loops, which complicates accessibility and requires additional installation and assembly space.

[0006] The object of the invention is to propose a compact earthing terminal which is easy and safe to operate and install.

[0007] According to the invention, the solution to the problem is achieved in an earthing terminal of the type mentioned in that the primary clamping part has at least one cable connection opening in a lateral connection area, which is designed to insert a connection cable along a cable insertion axis, wherein preferably the cable insertion axis of the cable connection opening is arranged substantially parallel to the central screw axis.

[0008] The stripped end of the connecting cable is inserted into the cable connection opening parallel to the central screw axis of the central clamping screw and secured, for example, with a cable clamping screw. The screw axis of the cable clamping screw is preferably aligned parallel to the minimum transversal of the central screw axis and the longitudinal axis of the duct. The connecting cables are thus inserted, for example, from below into the downwardly open cable connection openings and secured from the front—i.e., directly from the side of the person performing the installation—by tightening the clamping screws. The minimum transversal is the shortest connection between the two skew lines, i.e., the central screw axis of the central clamping screw and the longitudinal axis of the duct.

[0009] This allows connecting cables to be installed without loops and routed downwards in a straight line. This simplifies installation and reduces the required installation and mounting space.

[0010] It is preferably provided that at least two, preferably at least three, cable connection openings are arranged in a row in the connection area, wherein at least two cable insertion axes span a connection plane arranged parallel to the longitudinal axis of the channel.

[0011] In order to be able to connect several connecting cables to the grounding terminal in a compact manner, it is advantageous if at least two, preferably at least three, cable connection openings are arranged in a row in the connection area, with at least two cable entry axes spanning a connection plane arranged parallel to the longitudinal axis of the duct. The connecting cables are thus arranged in a row in the connection plane and form a right angle to the conductor fixed in the duct—without deforming the connecting cables. In this way, an entire group of connecting cables can be laid straight downwards without looping.

[0012] One embodiment of the invention provides that the primary clamping part has, on its side facing away from the primary clamping surface, a substantially flat mounting surface with at least one anti-twist device, in particular one projecting from the mounting surface, and is designed to be fastened to a fastening part, in particular a cable support system, for example a cable tray, in a rotationally secure manner, preferably releasably by means of the central clamping screw. This allows the earthing terminal to be attached to a particularly perforated cable support system easily and in a positionally secure manner, with the conductor being arranged in the longitudinal direction of the cable support system. The earthing terminal can be attached inside or outside the cable support system. The anti-twist device, formed for example by a locking lug, is inserted into the perforation of the cable support system during assembly.

[0013] A further development of the invention provides that at least one screw receiving opening has a non-circular first cross-sectional area and the central clamping screw has a non-circular second cross-sectional area that corresponds positively to the non-circular - in particular polygonal - first cross-sectional area. This further secures the earthing terminal against rotation and enables a nut to be easily screwed into the central clamping screw without having to hold it. For example, the screw receiving opening can have a square first cross-sectional area and the central clamping screw a corresponding square second cross-sectional area. In particular, the central clamping screw can be designed as a hinge screw. Hinge screws have a square cross-sectional area adjacent to the screw head.

[0014] A non-circular cross-section is defined here as a cross-section whose shape deviates from a circle. Non-circular cross-sections in this sense can be oval, of equal thickness, or angular—for example, triangular, square, or n-sided.

[0015] One embodiment of the invention provides that the primary clamping part has at least two primary grooves arranged essentially parallel to one another and spaced apart by a defined first distance. Preferably, the central screw axis of the central clamping screw is arranged essentially centrally between the two primary grooves arranged parallel to one another. As a result, the central clamping screw applies a uniform holding force to the conductors.

[0016] It is particularly advantageous if the secondary clamping part has a first secondary clamping surface and a second secondary clamping surface facing away from the first secondary clamping surface, which is preferably configured substantially parallel to the first secondary clamping surface. The first secondary clamping surface and the second secondary clamping surface are designed differently. The first secondary clamping surface is assigned to a first application, and the second secondary clamping surface is assigned to a second application. In particular, the first application is formed by a single-conductor grounding system, and the second application is formed by a two-conductor grounding system.

[0017] In order to be able to use the grounding terminal in a two-wire grounding system and to electrically connect it to two grounding conductors, it is advantageous if the second secondary clamping part has at least two first secondary grooves arranged essentially parallel to one another in a first secondary clamping surface. The secondary clamping part is placed on the primary clamping part such that the primary clamping surface of the primary clamping part and the first secondary clamping surface of the secondary clamping part face each other. The two primary grooves of the primary clamping part and the two first secondary grooves of the secondary clamping part thus form two channels, each suitable for accommodating one conductor.

[0018] In order to be able to use the earthing terminal in a single-conductor earthing system and to be able to create a secure and permanent electrical connection with just a single earthing conductor, it is advantageous if the secondary clamping part has only a single second secondary groove in the second secondary clamping surface. Preferably, the secondary clamping part has at least one support in the second secondary clamping surface, formed for example by a bulge - preferably two supports each formed by a bulge. The shape of the support or supports is advantageously reciprocal to the cross-section of at least one primary groove. Preferably, the support is spaced from the second secondary groove, wherein this second distance between the support and the second secondary groove corresponds to the first distance.

[0019] For the second application, the secondary clamping part is placed on the primary clamping part such that the primary clamping surface of the primary clamping part and the second secondary clamping surface of the secondary clamping part face each other. One primary groove of the primary clamping part and the only second secondary groove of the second secondary clamping surface of the secondary clamping part thus form a single channel suitable for accommodating a single conductor. The support(s) of the second secondary clamping surface is positioned in the other free primary groove of the primary clamping part and essentially fills it. As a result, the secondary clamping part – instead of a second conductor – is supported via the molded support in the free primary groove of the primary clamping part. When the central clamping screw is firmly tightened, the primary clamping surface of the primary clamping part and the second secondary clamping surface of the secondary clamping part are thus aligned essentially parallel to each other.Tilting of the secondary clamping part relative to the primary clamping part can thus be avoided when used on a single conductor.

[0020] In this way, an equally good clamping effect of the earthing terminal on the conductor or conductors can be achieved both when used with one conductor and when used with two conductors.

[0021] The earthing terminal is therefore equally suitable for single-wire earthing systems and for two-wire earthing systems, whereby it can be easily adapted to the respective application by simply turning the secondary clamping part.

[0022] The invention will be explained in more detail below with reference to non-limiting embodiments shown in the figures. Fig. 1 shows an earthing terminal according to the invention in a first embodiment in an axonometric view; Fig. 2 shows this earthing terminal in an exploded view; Fig. 3 shows an earthing terminal according to the invention in a second embodiment in a first application in an axonometric view; Fig. 4 shows this earthing terminal in an exploded view; Fig. 5 shows the earthing terminal from Fig. 3 in a second application in an axonometric view; and Fig. 6 this earthing terminal in an exploded view.

[0023] Identical parts are provided with the same reference symbols in the different versions.

[0024] Fig. 1shows an earthing terminal 1 according to the invention with a substantially cuboid-shaped primary clamping part 2 and a substantially cuboid-shaped secondary clamping part 3. The flat primary clamping part 2 has, as the largest surface of the cuboid, a primary clamping surface 21 and a mounting surface 24, which are arranged on opposite sides of the primary clamping part 2.

[0025] Primary grooves 22, 23 are formed into the primary clamping surface 21.

[0026] The secondary clamping part 3, which is also flat, has a secondary clamping surface 31 formed by one of the largest surfaces of the cuboid-shaped secondary part 3. Thirty-one secondary grooves 32, 33 are formed into the secondary clamping surface.

[0027] The two primary channels 22, 23 are arranged parallel to each other and spaced apart by a first distance a. The two secondary channels 32, 33 are also arranged parallel to each other and spaced apart by the same first distance a. The first distance a is measured between the centers or planes of symmetry of the primary channels 22, 23 and the secondary channels 32, 33, respectively.

[0028] In the assembled state of the earthing terminal 1, a primary groove 22; 23 and a secondary groove 32; 33 each form a channel 4, 5, which is designed to hold a conductor 6, 7, in particular designed as a round conductor - for example a wire, a rope or a cable - between the primary groove 22; 23 and a secondary groove 32; 33 in a force-fitting manner by means of a central clamping screw 8. In the assembled state of the earthing terminal 1, the channel longitudinal axes 4a, 5a of the channels 4, 5 are arranged parallel to one another and at the defined first distance a from one another and span a conductor plane ε.

[0029] As in Fig. 2 As can be seen, both the primary clamping part 2 and the secondary clamping part 3 each have a screw receiving opening 27, 37, wherein the screw receiving openings 27, 37 are arranged in alignment with one another in the direction of the central screw axis 8a of the central clamping screw 8 in the assembled state of the earthing terminal 1.

[0030] For the force-fitting contact of the primary clamping part 2 and the secondary clamping part 3 with the conductors 6, 7, the central clamping screw 8 is inserted into the screw receiving openings 27, 37 and tightened by a nut 9 so that the conductors 6, 7 are clamped between the primary clamping part 2 and the secondary clamping part 3.

[0031] The central screw axis 8a of the central clamping screw 8 is skewed in the assembled state of the earthing terminal 1 with respect to the channel longitudinal axes 4a, 5a of the channels 4, 5. The central screw axis 8a has no intersection point with the channel longitudinal axes 4a, 5a. Reference symbol t in Fig. 1 a minimal transversal t of the central screw axis 8a and the canal longitudinal axis 4a, 5a.

[0032] The screw receiving opening 27 is arranged between the primary grooves 22, 23 and the screw receiving opening 37 is arranged between the secondary grooves 32, 33, wherein the screw receiving openings 27, 37 have no intersection areas with the primary grooves 22, 23 and secondary grooves 32, 33.

[0033] The screw receiving openings 27, 37 have at least one non-circular cross-sectional area. In the illustrated embodiments, the screw receiving openings 27, 37 have the shape of a square socket.

[0034] Viewed in the direction of the minimum transversal t of the central screw axis 8a and the channel longitudinal axis 4a, 5a, the central screw axis 8a and the channel longitudinal axes 4a, 5a essentially enclose an angle o of approximately 90°. The minimum transversal t located in the conductor plane ε is the shortest connection between the two skew lines 4a and 8a or 5a and 8a, i.e., the channel longitudinal axes 4a and 5a of the channel 4 and 5, respectively, and the central screw axis 8a of the central clamping screw 8.

[0035] The primary clamping part 2 is larger than the secondary clamping part 3 when viewed in plan view in the direction of the central screw axis 8a. In a lateral connection area 25, which, again viewed in the direction of the central screw axis 8a, projects laterally beyond the plan area of ​​the secondary clamping part 3 by an excess x, the primary clamping part 2 has a plurality of cable connection openings 26, each of which is designed to insert a connecting cable 10 along a cable insertion axis 26a. The cable insertion axis 26a is defined by a longitudinal center axis of the cable connection opening 26—for example, by a rotational axis in the case of a cable connection opening 26 formed by a rotationally symmetrical bore. The cable insertion axes 26a of the cable connection openings 26 are arranged substantially parallel to the central screw axis 8a.

[0036] The stripped ends of the connecting cables 10 are inserted into the cable connection opening 26 parallel to the central screw axis 8a, i.e., the central clamping screw 8, and are each fixed, for example, by means of a cable clamping screw 11. The screw axes 11a of the cable clamping screws 11 are arranged parallel to the minimum transversal t, i.e., normal to the central screw axis 8a and normal to the channel longitudinal axes 6a, 7a. In the exemplary embodiments shown, three cable connection openings 26 are arranged in a row in the connection area 25, and the same number of cable clamping screws 11 are arranged in a row at an angle of 90° to the cable insertion axes 26a. At least two cable insertion axes 26a of the cable connection openings 26 span a connection plane γ arranged parallel to the channel longitudinal axes 6a, 7a, which is formed normal to the conductor plane ε.

[0037] The connecting cables 10 are thus arranged in a row in the connection plane γ and are essentially at a right angle to the conductor plane ε and the conductors 6, 7 fixed in the channels 5, 6.

[0038] As in Fig. 2As shown, the earthing terminal 1 is suitable for mounting on a fastening part, for example, a perforated cable support system 12, such as a commercially available U-shaped cable tray. The earthing terminal 1 is detachably fastened to the perforated cable support system 12 by means of the central clamping screw 8, wherein the central clamping screw 8 is guided through a hole 13 in the cable support system 12. To enable simple assembly, it is advantageous if the central clamping screw 8 is formed by a hinge screw. Hinge screws generally have a semicircular and driveless screw head with a square shoulder below the screw head, which engages in the hole 13 and thus prevents the hinge screw from twisting when the nut 9 is tightened. Furthermore, the square shoulder engages in the non-circular, for example square, cross-sectional area of ​​the screw receiving opening 27, 37 and acts as an anti-twist device for the earthing terminal 1.

[0039] To additionally prevent the earthing terminal 1 from twisting and to ensure precise positioning of the earthing terminal 1, the essentially flat mounting surface 24 of the primary clamping part 2 has an anti-twist device 28 formed by a locking lug protruding from the mounting surface 24. This allows the earthing terminal 1 to be easily and securely attached to a perforated cable support system 12, for example, with the conductors 6, 7 arranged in the longitudinal direction of the cable support system 12. The earthing terminal 1 can be mounted inside or outside the cable support system 12. The anti-twist device 28 is inserted into the perforation 13 of the cable support system 12 during assembly.

[0040] The Fig. 3 to Fig. 6 The earth terminal 1 shown differs from the one shown in the Fig. 1 and Fig. 2The embodiment shown is characterized in that the secondary clamping part 3 has, in addition to the first secondary clamping surface 31, a second secondary clamping surface 34 facing away from the latter, which is formed substantially parallel to the first secondary clamping surface 31. The first secondary clamping surface 31 and the second secondary clamping surface 34 are designed differently.

[0041] The first secondary clamping surface 31 is a Fig. 3 and Fig. 4 shown first application for a two-wire earthing system and the second secondary terminal surface a Fig. 5 and Fig. 6 shown second application case for a single-wire earthing system.

[0042] In order to be able to use the earthing terminal 1 in a two-wire system and to connect it electrically with two conductors 6, 7, the secondary clamping part 3 in the first secondary clamping surface 31 - as in the case of Fig. 1 and Fig. 2shown embodiment - two first secondary grooves 32, 33 arranged essentially parallel to one another. The secondary clamping part 3 is placed on the primary clamping part 2 such that the primary clamping surface 21 of the primary clamping part 2 and the first secondary clamping surface 31 of the secondary clamping part 3 face each other. The two primary grooves 22, 23 of the primary clamping part 2 and the two first secondary grooves 32, 33 of the secondary clamping part 3 thus form two channels 4, 5, in each of which a conductor 6, 7 can be electrically contacted by clamping (see Fig. 3 and Fig. 4 ).

[0043] In order to be able to use this earthing terminal 1 in a single-conductor earthing system and to be able to create a secure and permanent electrical connection with just a single earthing conductor 6, the secondary clamping part 3 has only a single second secondary groove 35 in the second secondary clamping surface 34. Furthermore, the secondary clamping part 3 has two supports 38 in the second secondary clamping surface 34, each formed by a bulge. The shape of the bulges is advantageously reciprocal to the cross-section of at least one primary groove 22, 23. The supports 38 are spaced from the second secondary groove 35, wherein the second distance b between the supports 38 and the second secondary groove 34 corresponds to the first distance a. The second distance b is measured between the center or plane of symmetry of the second secondary groove 35 and the center or plane of symmetry of the supports 38.

[0044] For use in a single-conductor earthing system, the secondary clamping part 3 is placed onto the primary clamping part 2 such that the primary clamping surface 21 of the primary clamping part 2 and the second secondary clamping surface 34 of the secondary clamping part 3 face each other. One primary groove 22 of the primary clamping part 2 and the single second secondary groove 35 of the second secondary clamping surface 34 of the secondary clamping part 3 thus form a single channel 4 suitable for receiving a single conductor 6. The support 38 of the second secondary clamping surface 34 is positioned in the other free primary groove 23 of the primary clamping part 2 and essentially fills it. As a result, the secondary clamping part 3—instead of a second conductor 7—is supported via the molded-on support 38 in the free primary groove 23 of the primary clamping part 2.When the central clamping screw 8 is tightened, the primary clamping surface 21 of the primary clamping part 2 and the second secondary clamping surface 34 of the secondary clamping part 3 are aligned essentially parallel to each other. Tilting of the secondary clamping part 3 relative to the primary clamping part 2 can thus be avoided when used on a single conductor 6 (see . Fig. 5 and Fig. 6 ).

[0045] Both when used with one conductor 6 and when used with two conductors 6, 7, an equally good clamping effect of the earthing terminal 1 on the conductor 6 or on the conductors 6, 7 can be achieved.

[0046] The earth terminal 1 of the Fig. 3 to Fig. 6 The design variant shown is therefore equally suitable for two-wire earthing systems and for single-wire earthing systems, whereby a simple adaptation to the respective application can be achieved by turning the secondary clamping part 3.

Claims

1. Earthing terminal (1) with at least one channel (4, 5) arranged between a primary clamping part (2) and a secondary clamping part (3), which channel (4, 5) is formed by a primary groove (22, 23) in a primary clamping surface (21) of the primary clamping part (2) and at least one secondary groove (32, 33) in a secondary clamping surface (31, 34) of the secondary clamping part (3), wherein the primary clamping part (2) and the secondary clamping part (3) can be pressed relative to one another by means of at least one central clamping screw (8) inserted into aligned screw receiving openings (27, 28) of the primary clamping part (2) and the secondary clamping part (3), wherein a central screw axis (8a) of the central clamping screw (8) is formed skew to a channel longitudinal axis (4a, 5a) of the channel (4, 5) and the central screw axis (8a) and the canal longitudinal axis (4a, 5a) - in the direction of a minimum transversal (t) of the central screw axis (8a) and the canal longitudinal axis (4a,5a) - essentially span an angle (α) of approximately 90°, and wherein the primary clamping part (2) and the secondary clamping part (3) are designed to hold a conductor (6, 7), in particular a round conductor, in the channel (4a, 5a) between the primary groove (22, 23) and the secondary groove (32, 33) in a force-fitting manner, , characterized in that the primary clamping part (2) has at least one cable connection opening (26) for a connecting cable (10) in a lateral connection area (25), which is designed to insert a connecting cable (10) along a cable insertion axis (26a), wherein the cable insertion axis (26a) of the cable connection opening (26) is preferably arranged substantially parallel to the central screw axis (8a).

2. Earthing terminal (1) according to claim 1, characterized in thatthe connecting cable (10) can be fixed in the cable connection opening (26) via at least one cable clamping screw (11), wherein the cable clamping screw (11) has a screw axis (11a) arranged parallel to the minimum transversal (t).

3. Earthing terminal (1) according to claim 1 or 2, characterized in that at least two, preferably at least three, cable connection openings (26) are arranged in a row in the connection area (25), wherein at least two cable insertion axes (26a) span a connection plane (γ) arranged parallel to the longitudinal axis (4a, 5a) of the channel.

4. Earthing terminal (1) according to one of claims 1 to 3, characterized in thatthe primary clamping part (2) has, on its side facing away from the primary clamping surface (21), a substantially flat mounting surface (24) with at least one anti-twist device (28) - in particular projecting from the mounting surface (24) - and is designed to be fastened to a fastening part, in particular a cable support system (12), in a rotationally secure manner - preferably releasably by means of the central clamping screw (8).

5. Earthing terminal (1) according to one of claims 1 to 4, characterized in that at least one screw receiving opening (27, 37) has at least one non-circular first cross-sectional area and the central clamping screw (8) has a second cross-sectional area corresponding in a form-fitting manner to the non-circular first cross-sectional area.

6. Earthing terminal (1) according to claim 5, characterized in thatat least one screw receiving opening (27, 37) has a square first cross-sectional area, wherein preferably the central clamping screw (8) has a square second cross-sectional area and is particularly preferably designed as a hinge screw.

7. Earthing terminal (1) according to one of claims 1 to 6, characterized in that the primary clamping part (2) has at least two primary grooves (22, 23) arranged substantially parallel to one another, which are spaced apart from one another at a defined first distance (a).

8. Earthing terminal (1) according to claim 7, characterized in that the central screw axis (8a) of the central clamping screw (8) is arranged substantially centrally between the two primary grooves (22, 23) arranged parallel to one another.

9. Earthing terminal (1) according to claim 7 or 8, characterized in thatthe secondary clamping part (3) has a first secondary clamping surface (31) and a second secondary clamping surface (32) facing away from the first secondary clamping surface, which is preferably formed substantially parallel to the first secondary clamping surface (31).

10. Earthing terminal (1) according to claim 9, characterized in that the second secondary clamping part (3) has at least two first secondary grooves (32, 33) arranged substantially parallel to one another in a first secondary clamping surface (34).

11. Earthing terminal (1) according to claim 9 or 10, characterized in that the secondary clamping part (3) has a second secondary groove (35) in the second secondary clamping surface (34).

12. Earthing terminal (1) according to one of claims 9 to 11, characterized in thatthe secondary clamping part (3) has at least one - preferably two - supports (38) in the second secondary clamping surface (34), in particular formed by a bulge, wherein the shape of the support (38) is preferably reciprocal to the cross-section of at least one primary channel (22, 23).

13. Earthing terminal (1) according to claim 12, characterized in that the at least one support (38) is spaced from the second secondary channel (34), wherein a second distance (b) between the support (38) and the second secondary channel (34) corresponds to the first distance (a).

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