CN110546817B

CN110546817B - Connecting terminal

Info

Publication number: CN110546817B
Application number: CN201880026661.8A
Authority: CN
Inventors: 托马斯·维特
Original assignee: Wago Verwaltungs GmbH
Current assignee: Wago Verwaltungs GmbH
Priority date: 2017-05-05
Filing date: 2018-04-20
Publication date: 2021-05-18
Anticipated expiration: 2038-04-20
Also published as: WO2018202445A1; DE102017109701A1; EP3619772A1; CN110546817A; EP3619772B1

Abstract

The invention relates to a connection terminal having at least one busbar part, at least one clamping spring and at least one sleeve, wherein the clamping spring has a clamping leg oriented toward the busbar part, wherein a clamping point for clamping an electrical conductor is formed between the busbar part and the clamping leg, wherein the clamping spring has a spring bracket connected to the clamping leg and an abutment leg connected to the spring bracket, wherein one or more first holding regions are formed at the clamping leg and/or the abutment leg of the clamping spring, by means of which first holding regions the busbar part and the sleeve are positively connected to the clamping spring.

Description

Connecting terminal

Technical Field

The invention relates to a terminal having at least one busbar part, at least one clamping spring and at least one sleeve, wherein the clamping spring has a clamping leg oriented toward the busbar part, wherein a clamping point for clamping an electrical conductor is formed between the busbar part and the clamping leg, wherein the clamping spring has a spring bracket connected to the clamping leg and an abutment leg connected to the spring bracket.

Background

Such a terminal is known from DE 19610958 a 1.

Disclosure of Invention

The invention is based on the object of providing a terminal block which is particularly easy to install and has the simplest possible design.

In the case of the aforementioned terminal, the object is solved by: one or more first retaining regions are formed on and/or against the clamping legs of the clamping spring, by means of which the bus bar piece and the sleeve are positively connected to the clamping spring. The invention allows: the three elements, i.e., the bus bar piece, the clamping spring and the sleeve, are each designed in a relatively simple manner, independently of one another, in particular in the following manner: two individual elements of the three individual elements are not yet self-supporting, in particular, are not securely fastened to one another without additional support. The joint action of the three elements, i.e. the busbar part, the clamping spring and the sleeve, wherein the busbar part and the sleeve are connected to the clamping spring in a form-fitting manner by the clamping spring, makes it possible to realize a self-supporting wire connection which can be installed particularly easily and comfortably. Disassembly is also readily possible.

By means of the form-fitting connection, the three elements, i.e. the busbar arrangement, the clamping spring and the sleeve, are reliably coupled to one another, so that the components are prevented from falling out of one another or the clamping spring is prevented from slipping out of place in all three dimensions of freedom. This also achieves loss safety of the individual components. The terminal according to the invention can be used individually and optionally already as a terminal, but can also be used as a contact insert of a terminal designed with other features.

The sleeve thereby forms a cover for the arrangement of bus bar pieces and clamping springs. In addition, increased stability of the assembly and protection of the clamping spring, in particular protection of the spring bow and protection of the region of the contact leg and the clamping leg directly adjoining the spring bow, are thereby achieved by the support at a plurality of points.

The individual elements, such as the bus bar piece, the clamping spring and the sleeve, can each be a single-piece component. The clamping spring and the bus bar piece are made of metal, and the sleeve can optionally be made of an insulating material (plastic) or metal.

Since no further fastening means are required apart from the fastening by form-fitting, the terminal can be easily mounted or dismounted during the process.

The terminal can be operated in different ways with respect to opening and closing the clamping point. Thus, for example, a lever operation is possible by: to operate the lever to supplement the terminal. The actuating lever can be supported, for example, on the sleeve. Alternatively, the operation can be effected via an external tool, which is not part of the connection terminal.

According to an advantageous further development of the invention, it is provided that the sleeve has an enclosing region in which at least a part of the clamping spring and/or a part of the busbar arrangement is accommodated. In this way, the clamping spring and/or the bus bar piece are secured against rotation in the longitudinal direction and are additionally protected against environmental influences. The enclosing region can in particular enclose the spring bracket of the clamping spring and, if applicable, also the clamping leg and/or a section of the contact leg connected to the spring bracket. The surrounding region of the sleeve can surround the mentioned section of the clamping spring or of the busbar arrangement over the entire circumference of the sleeve (ring-shaped) or, if the surrounding region has an interruption, for example, on the circumferential side, at least partially.

According to an advantageous further development of the invention, it is provided that the sleeve has a line insertion region, at which a line insertion opening for inserting an electrical line into the sleeve up to the clamping point is present. This simplifies the introduction of the electrical conductor into the connection terminal up to the clamping point. The line insertion opening can be designed, for example, in the form of a cylinder or funnel in order to guide the electrical line in a targeted manner to the clamping point.

According to an embodiment, the enclosing region of the sleeve and the wire lead-in region can overlap one another or be arranged independently of one another. In an advantageous embodiment, the surrounding region extends, for example, from the clamping point over only a part of the longitudinal extent of the sleeve. Accordingly, the sleeve surrounds at least a part of the clamping spring and/or a part of the bus bar piece only over the partial region. The wire insertion region begins with a wire insertion opening at the end of the sleeve facing away from the clamping point. The wire lead-in region can extend over the entire length of the sleeve. The lead-in direction and the direction of penetration of the electrical conductor up to the clamping point can extend in particular in the longitudinal direction of the sleeve.

The sleeve can in particular have a first longitudinal region and a second longitudinal region in the surrounding region. At least one partial region of the spring is accommodated in the first longitudinal region. A wire introduction opening is formed in the second longitudinal region.

According to an advantageous further development of the invention, it is provided that the bus bar piece has at least one clamping spring holding element, via which the bus bar piece is positively connected to the clamping spring, and/or that the bus bar piece has at least one sleeve holding element, via which the bus bar piece is positively connected to the sleeve. In this way, a reliable positive connection can be produced between the bus bar piece and the clamping spring and/or the sleeve.

According to an advantageous further development of the invention, it is provided that the first sleeve holding element of the busbar arrangement has at least one first holding finger projecting from the busbar arrangement or is designed as such a first holding finger. In this way, an end stop can be formed, in particular when the sleeve is pushed onto the device formed by the busbar parts and the clamping spring. The surrounding region of the sleeve can have a stop surface for the busbar parts, for example for the retaining fingers. The first holding finger can project, in particular, at an angle, for example, a right angle or an oblique angle, from a plane of the busbar arrangement at which the clamping point (wire connection region of the busbar arrangement) is formed.

According to an advantageous further development of the invention, it is provided that the second sleeve holding element of the busbar arrangement has at least one slot-like recess. In this way, the bus bar piece can be positively coupled to the sleeve at the second location by: the corresponding retaining element of the sleeve can engage into the slit-like recess.

According to an advantageous further development of the invention, it is provided that the sleeve has at least one bus bar piece holding element, via which the sleeve is positively connected to the bus bar piece, and/or that the sleeve has at least one clamping spring holding element, via which the sleeve is positively connected to the clamping spring. In this way, the sleeve can be connected to the bus bar piece and/or the clamping spring in a form-fitting manner in a particularly reliable manner.

According to an advantageous further development of the invention, it is provided that the sleeve has a second holding region which projects from the surrounding region, wherein the second holding region has at least one clamping spring holding element of the sleeve and/or at least one bus bar piece holding element of the sleeve. The holding region can be formed, for example, in a plate-like or plate-like manner.

According to an advantageous further development of the invention, it is provided that the clamping spring holding element of the sleeve has at least one groove and/or that the busbar part holding element of the sleeve has at least one hooking element, wherein the holding region can have a separating wall between the hooking element and the groove. The groove and/or the hooking element can be provided in particular at the second retaining region of the sleeve. The separating wall can form a separation between the hooking element and the groove. A particularly simple and reliable form-fitting coupling of the sleeve to the clamping spring and/or the bus bar piece is thereby possible.

According to an advantageous further development of the invention, it is provided that the busbar part has at least one recess on its side pointing towards the separating wall, into which recess at least one part of the separating wall engages. The recess, which can be formed as an indentation, for example, can run in the extension direction of the separating wall in a groove-shaped manner, so that the separating wall can be inserted into the recess via a specific longitudinal extension. By means of the recess, bending of the separating wall can be minimized when the conductor is introduced into the terminal. As a further positive effect of the recess in the busbar portion, a high rigidity of the busbar portion in this region is achieved, which contributes to a reduction in the load on the further support means between the power rail device and the sleeve. By means of the separating wall, the lead-through and the spring-operated chamber region are reliably separated from one another in this way.

According to an advantageous further development of the invention, it is provided that the clamping spring has at least one bus bar piece holding element, via which the clamping spring is positively connected to the bus bar piece, and/or that the clamping spring has at least one sleeve holding element, via which the clamping spring is positively connected to the sleeve. In this way, the clamping spring can be coupled in a form-fitting manner particularly reliably at the bus bar piece and/or the sleeve.

In this case, the conductor rail holding element of the clamping spring can be connected in particular to the clamping spring holding element of the sleeve. The sleeve holding element of the clamping spring can be connected with the clamping spring holding element of the sleeve. The sleeve holding element of the busbar piece can be connected with the busbar piece holding element of the sleeve.

The electrically conductive rail-holding element of the clamping spring and/or the sleeve-holding element of the clamping spring can be arranged at one or at different first holding regions of the clamping spring.

According to an advantageous further development of the invention, it is provided that the sleeve retaining element of the clamping spring has at least one slot-like recess provided at the clamping leg and/or at the abutment leg. In this way, the sleeve can be coupled to the clamping spring in a form-fitting manner in a simple and reliable manner.

According to an advantageous further development of the invention, it is provided that the clamping leg has at least one clamping claw with a clamping edge at the free end and at least one second retaining finger which projects in the same or a different direction from the clamping claw at the clamping leg. The second holding finger can have a pure holding function, that is to say for a positive-locking coupling of the clamping spring, for example at the sleeve or at the busbar part. Accordingly, the holding fingers do not have a clamping function for clamping the electrical conductor. The clamping function is in this case assumed solely by the clamping jaws with their clamping edges. The clamping jaw can thus extend forward separately from the retaining finger at the free end of the clamping leg, so that the aforementioned slit-like recess, which forms the sleeve-retaining element of the clamping spring, can be present between the clamping jaw and the retaining finger at the clamping leg of the clamping spring.

The second holding finger can furthermore have an abutment surface for abutment against an actuating element for actuating the clamping spring in order to bring the clamping point from the closed position into the open position.

According to an embodiment of the terminal, the terminal can be formed without an additional insulating material housing. In this case, at least a part of the function of the insulating material housing can be assumed by the sleeve. The connecting terminal can also be formed with an additional insulating material housing which at least partially surrounds the busbar parts, the clamping spring and the sleeve.

The busbar part can have a conductor stop. The line stop is arranged transversely to the line insertion direction, in particular perpendicularly thereto. The conductor connecting region of the busbar arrangement with the clamping point can extend parallel to the conductor insertion direction.

In order to form the clamping point, the busbar part can have a bulge, for example in the form of a stamped-out part, which is provided in the conductor connection region and projects toward the clamping leg. The ridge can extend over the entire width of the busbar component or only over a part of the width. In particular, the bus bar piece can have a bearing surface for bearing a retaining region of the sleeve, viewed in the wire insertion direction, next to the bulge.

The bus bar piece and/or the clamping spring can have a varying cross section by way of its expansion from one end to the other end. The contact leg can thus for example be narrowed from a first, larger cross section to a second, smaller cross section starting from the spring bracket, for example by: the width of the material against the legs decreases. The region with the second smaller cross section can extend as far as the bus bar piece holding element of the clamping spring.

Drawings

The invention is explained in detail below on the basis of embodiments with the aid of the figures.

The figures show:

FIG. 1 shows a clamping spring in a side view and

FIG. 2 shows a busbar component in a side view and

FIG. 3 shows the sleeve in a side view and

fig. 4 shows, in a side view, a connecting terminal formed from the above-described elements of fig. 1 to 3 and

fig. 5 to 7 show the connecting terminal according to fig. 4 in different perspective views and

fig. 8 shows the terminal in a sectional view according to section a-a of fig. 4.

Detailed Description

The following features are shown in the drawings:

2 bus bar piece

3 clamping spring

5 sleeve barrel

10. 11, 12 clamping spring first holding region

18 recess of bus bar piece

19 clamping spring holding element for a busbar assembly

20 socket contact (fork contact)

21 basic region of a busbar component

22 transition region of a busbar piece to a second sleeve holding element of the busbar piece

23 second sleeve holding element of a busbar part

24 transition region of a bus bar piece to a line connection region of a bus bar piece

25 wire connection region of bus bar piece

26 raised portion of wire connection region

27 first sleeve holding element (first holding finger) of a busbar piece

28 shoulder region of a busbar piece

29 slit-like recesses of the second sleeve holding element

30 clamping spring leg

31 clamping spring bus bar piece holding element

32 additional sleeve holding element of a clamping spring

33 spring bow

34 clamping leg

35 clamping jaw

36 clamping edge

37 second holding finger

38 sleeve retaining element of a clamping spring

39 shoulder region at the clamping leg

50 first longitudinal section of the surrounding region of the sleeve

51 second longitudinal section of the surrounding region of the sleeve

52 envelope region of the sleeve

53-sleeve first busbar piece holding element

54 second holding area of the sleeve

55-sleeve clamping spring holding element

56 separating wall of the second holding area

57 sleeve second bus bar piece holding member

58 sleeve fixing mechanism

59 contact surface for contact leg of clamping spring

60 lead-in opening

61 sleeve wire lead-in area

Fig. 1 to 3 show the elements, i.e. the busbar parts 2, the clamping spring 3 and the sleeve 5, as individual parts before they are assembled to form a connecting terminal according to further figures. It can be seen that the

first holding regions

10, 11, 12 are arranged spatially distributed at the clamping spring 3. The busbar parts 2 project to the right from the base region 21 and have fork-like contacts which form the plug contacts 20 of the busbar parts 2. The invention is also suitable for bus bars of another design, for example for bus bars having another type of plug contact or for bus bars without plug contacts.

The base region 21 connects the fork-shaped connection flags of the plug contact 20, which branch off to the right, to one another, and connects the further sections of the busbar arrangement 2, which branch off to the left, to one another. For this purpose, the base region 21 can be formed in a U-shape, as is illustrated by the perspective views in fig. 5 to 7.

The base region 21 passes into a second sleeve holding element 23 via the clamping spring holding element 19 and the substantially right-angled connecting section 22. At the same time, the second sleeve holding element 23 forms a line stop for an electrical line introduced into the connection terminal. Furthermore, the base region 21 merges via the clamping spring holding element 19 and the S-shaped transition region 24 into a horizontally running conductor connection region 25.

The sleeve 5 has a longitudinal direction corresponding to a lead-in direction L in which an electrical lead can be introduced into the sleeve 5. The electrical lines are introduced into the sleeve 5 from the left in the illustration of fig. 3 (corresponding to the arrows under the letter L). In the wire insertion direction L, the sleeve 5 has at the surrounding region 52 first a first longitudinal section 50 and then a second longitudinal section 51, which is connected to the first longitudinal section 50. The second longitudinal section 51 serves to accommodate the clamping spring 3 and/or parts of the busbar parts 2 in the interior of the enclosing region 52. The fastening element 58 serves to latch the fastening sleeve 5 in the insulating material housing of the connecting terminal. The second holding region 54 projects from the surrounding region 52 in the wire introduction direction L at the sleeve 5. As can be seen from the perspective view, the second holding region can be designed as a substantially flat, disk-shaped component and be formed in one piece with the surrounding region 52.

In fig. 4 to 6, the clamping spring is shown in its relaxed position, that is to say in the following position: in this position, the electrical line is not clamped between the clamping edge 36 and the bulge 26 and the clamping leg 34 is not additionally deflected. Fig. 7 shows the clamping leg 34 in a deflected position, in which it can be seen that the clamping edge 36 is spaced apart from the bulge 26. It is advantageous that: the clamping spring also has a certain pretension in its relaxed position. A clamping point for the electrical line is formed between the clamping edge 36 and the bulge 26.

In this case, the first holding region 11 of the clamping spring is accommodated in the surrounding region 52 of the sleeve 5 together with the section of the clamping spring forming the further sleeve holding element 32. Furthermore, this is illustrated by fig. 5.

Fig. 4 illustrates: a second holding region 54 of the sleeve 5 extends through between the clamping claw 35 and the second holding finger 37, so that the clamping claw 35 is not visible. In the relaxed position of the clamping spring 3, the second retaining finger 37 does not rest on the busbar part 2 or its clamping section 25.

It can also be seen that the first retaining fingers 27, which project obliquely upward from the wire connection region 25, rest against the first busbar part retaining element 53, which is formed with a corresponding slope, or are spaced apart from the first busbar part retaining element with a certain tolerance. Furthermore, the bus bar piece holding element 31 of the clamping spring 3 is fixed to the clamping spring holding element 19 of the bus bar piece 2. For this purpose, the busbar portion holding element 31 is formed with lateral openings in the form of a fork, as is also illustrated in a perspective view, in particular in fig. 6 and 7.

It can also be seen that the clamping spring extends with the clamping leg 34 into the region of the clamping spring retaining element 55 of the sleeve 5 and is retained there. Furthermore, a form-fitting connection is formed between the second sleeve holding element 23 of the busbar arrangement 2 and the conductive rail holding element 57 of the sleeve 5.

As fig. 5 additionally shows, the width of the material of the bus bar piece 5 changes over its longitudinal extent and thus its cross section. At the transition from the line connection region 25 to the first retaining finger 27, a shoulder region 28 of the busbar part 2 is provided, which projects substantially at right angles laterally from the line connection region 25.

Fig. 6 and 7 show that the surrounding region 52 of the sleeve 5 is not completely closed, but rather has a slit-like opening extending in the longitudinal direction in the wire insertion region 61.

As can also be seen from fig. 5, the clamping leg 34 is divided at the end into a clamping claw 35 and a second holding finger 37, so that a slot-like recess is formed between the clamping claw 35 and the second holding finger 37, which recess forms a sleeve holding element 38 of the clamping spring 3 in the first holding region 10 of the clamping spring 3.

Furthermore, it can be seen from the views in fig. 6 and 7 that the cross section of the clamping spring 3 also changes over the longitudinal extent of said clamping spring, for example by a change in the material width. In particular, in the transition region of the clamping leg 34 from the part accommodated in the enclosing region 52 to the part of the clamping leg 34 protruding from the enclosing region 52, the clamping leg expands its width, for example by a shoulder region 39 arranged substantially vertically.

For mounting the connecting terminal, the three elements, namely the busbar part 2, the clamping spring 3 and the sleeve 5, are assembled in such a way that the clamping spring is first coupled via its first holding region 12, i.e. the busbar part holding element 31, to the clamping spring holding element 19 of the busbar part 20. The clamping spring 3 is thus already loosely held at the bus bar piece 2, but can be released again upon a corresponding movement of the unit. For further fixing, the sleeve 5 is now guided with the second holding region 54 to the busbar fitting 2, wherein the other sleeve holding element 32 of the clamping spring is accommodated in the enclosing region 52. By bringing the second holding region 54 into contact with the clamping leg 34, said clamping leg is deflected slightly upwards from the relaxed position. The sleeve 5 can be supported with the second holding region 34 on the upper side of the wire connection region 25 directed toward the bulge 26 and can slide along said upper side. The bulge 26 does not extend over the entire width of the wire connection region 25, but rather a narrow planar region remains laterally of the bulge 26, on which planar region the second retaining region 54 can slide along the surface of the wire connection region 25 alongside the bulge 26. In the further course of the advancing movement of the sleeve 5, the free ends of the clamping legs 34 reach the clamping spring retaining elements 55 of the sleeve, i.e. the clamping legs 34 are moved back into their relaxed position and engage in the recesses of the second retaining region 54, which recesses form the clamping spring retaining elements 55. In this case, the sleeve 5 can be pushed so far that the first sleeve holding element 27, which is embodied in the form of a holding finger, abuts the first busbar piece holding element 53 of the sleeve 5. The final mounting position of the connecting terminal, shown in fig. 4 to 6, is then reached, in which all the positive-locking elements engage one another and cause the mentioned fixing of the components of the connecting terminal. The dismounting member is possible by: the sleeve is simply pulled out of the unit formed by the clamping spring 3 and the bus bar piece 2 against the conductor insertion direction L with a high force effort. In this case, the following forces must be used: by means of this force, the clamping leg 34 of the clamping spring 3 is deflected again upwards, so that the raised region of the separating wall 56 can also slide through under said clamping leg. The clamping spring 3 can easily be released from the bus bar piece 2 if the sleeve 5 is removed.

Fig. 8 shows a section through the connecting terminal according to fig. 4 in the cross section a-a. Thereby, in particular, it is elucidated: the busbar fitting 2 can have a recess 18, for example in the region of the line connection region 25, for example in the form of a punch on the surface side of the busbar fitting 2 directed toward the separating wall 56. As can be seen, the recess 18 can be designed, in particular, as a longitudinal groove, for example as a groove or another suitable shape, depending on the type of groove. The separating wall 56 has a corresponding shape on the side pointing toward the busbar part 2, which shape has a bevel, via which the separating wall 56 can be inserted into the recess 18. As mentioned, the fixing of the recess 18 and the separating wall 56 via its insertion region into the recess 18 minimizes the bending of the separating wall 56 during the insertion of the line. Furthermore, the support of the separating wall 56 in the recess 18 contributes to mechanically relieving the load of the support region formed between the first sleeve holding element 27 and the first busbar piece holding element 53.

Claims

1. A connection terminal having at least one busbar part (2), at least one clamping spring (3) and at least one sleeve (5), wherein the clamping spring (3) has a clamping leg (34) oriented toward the busbar part (2), wherein a clamping point for clamping an electrical conductor is formed between the busbar part (2) and the clamping leg (34), wherein the clamping spring (3) has a spring bow (33) connected to the clamping leg (34) and an abutment leg (30) connected to the spring bow (33), characterized in that one or more first retaining regions (10, 11, 12) are formed at the clamping leg and/or the abutment leg of the clamping spring, by means of which first retaining regions the busbar part (2) and the sleeve (5) are connected to the clamping spring (3) in a form-fitting manner, wherein the sleeve (5) has an enclosing region (52) in which at least a part of the clamping spring (3) and/or a part of the busbar piece (2) is accommodated, wherein the sleeve (5) has a second retaining region (54) which projects out of the enclosing region (52), wherein the second retaining region (54) has at least one clamping spring retaining element (55) of the sleeve (5) and/or at least one busbar piece retaining element (53, 57) of the sleeve (5).

2. A terminal block according to claim 1, characterised in that the sleeve (5) has a conductor lead-in region (61) at which a conductor lead-in opening (60) for the introduction of an electrical conductor into the sleeve (5) up to the clamping point is present.

3. A terminal according to one of the preceding claims, characterized in that the busbar arrangement (2) has at least one clamping spring retaining element (19), via which the busbar arrangement (2) is connected in a form-fitting manner to the clamping spring (3), and/or in that the busbar arrangement (2) has at least one sleeve retaining element (23, 27), via which the busbar arrangement (2) is connected in a form-fitting manner to the sleeve (5).

4. A terminal according to claim 3, characterised in that the first sleeve-retaining element (27) of the busbar piece (2) has at least one first retaining finger projecting from the busbar piece (2).

5. A terminal according to claim 4, characterised in that the second sleeve-retaining element (23) of the busbar arrangement (2) has at least one slot-like recess (29).

6. A terminal according to claim 1 or 2, characterized in that the sleeve (5) has at least one busbar piece holding element (53, 57) via which the sleeve (5) is connected in a form-fitting manner to the busbar piece (2), and/or in that the sleeve (5) has at least one clamping spring holding element (55) via which the sleeve (5) is connected in a form-fitting manner to the clamping spring (3).

7. A terminal according to claim 6, characterized in that the clamping spring retaining element (55) of the sleeve (5) has at least one groove and/or the busbar part retaining element (53, 57) of the sleeve (5) has at least one hooking element, wherein the retaining region (54) can have a separating wall (56) between the hooking element and the groove.

8. A terminal according to claim 7, characterised in that the busbar component (2) has at least one recess (18) on its side pointing towards the separating wall (56), into which recess at least a part of the separating wall (56) is inserted.

9. The connection terminal according to claim 1 or 2, characterized in that the clamping spring (3) has at least one busbar piece holding element (31) via which the clamping spring (3) is connected in a form-fitting manner to the busbar piece (2), and/or in that the clamping spring (3) has at least one sleeve holding element (38) via which the clamping spring (3) is connected in a form-fitting manner to the sleeve (5).

10. A terminal according to claim 9, characterized in that the sleeve retaining element (38) of the clamping spring (3) has at least one slot-like recess provided at the clamping leg (34) and/or at the abutment leg (30).

11. A terminal block according to claim 1 or 2, characterized in that the clamping leg (34) has at its free end at least one clamping claw (35) with a clamping edge (36) and at least one second retaining finger (37) which projects in the same or a different direction from the clamping claw (35) at the clamping leg (34).