CONNECTING TERMINAL

Abstract

A connecting terminal (A, B) comprising: a housing (1) comprising a conductor inlet opening (8) configured to receive a conductor (9) to be clamped, the housing (1) comprising a conductor clamping region extending from the conductor inlet opening (8) in an insertion direction of the conductor (9) to be clamped; a current rail (3) disposed in the housing (1) and forming at least a first boundary of the conductor clamping region; and a spring clamp (4) disposed in the housing (1) and configured to exert a clamping force towards the first boundary of the conductor clamping region shall provides a more reliable operation over an extended period of time, in particular with maximum size conductors. To that end, the current rail (3) comprises a first extension (27) forming a second boundary of the conductor clamping region.

Claims

1. A connecting terminal (A, B) comprising: a housing (1) comprising a conductor inlet opening (8) configured to receive a conductor (9) to be clamped, the housing (1) comprising a conductor clamping region extending from the conductor inlet opening (8) in an insertion direction of the conductor (9) to be clamped; a current rail (3) disposed in the housing (1) and forming at least a first boundary of the conductor clamping region; and a spring clamp (4) disposed in the housing (1) and configured to exert a clamping force towards the first boundary of the conductor clamping region; wherein the current rail (3) comprises a first extension (27) forming a second boundary of the conductor clamping region.

2. The connecting terminal (A, B) of claim 1, wherein the first boundary is perpendicular to the second boundary.

3. The connecting terminal (A, B) of claim 1 or 2, wherein the housing (1) comprises a first wall forming a third boundary of the conductor clamping region, wherein the first and third boundaries are located on opposite sides of the conductor clamping region.

4. The connecting terminal (A, B) of any of the preceding claims, wherein the first extension (27) is configured to limit a movement of the spring clamp (4) in a direction perpendicular to the direction of the clamping force.

5. The connecting terminal (A, B) of any of the preceding claims, wherein the current rail (3) is L-shaped.

6. The connecting terminal (A) of any of the preceding claims, wherein the first extension (27) forms a cantilever located adjacent to a first end of the spring clamp (4).

7. The connecting terminal (A) of claims 5 and 6, wherein the first extension (27) extends from a first leg of the L-shaped current rail (3) and wherein the current rail (3) comprises a second extension (28) extending from a second leg of the L-shaped current rail (3) and forming a cantilever located adjacent to a second end of the spring clamp (4).

8. The connecting terminal (A) of claim 6 or 7, wherein the housing (1) comprises a second wall extending the second boundary of the conductor clamping region.

9. The connecting terminal (B) of claim 5, wherein the first extension (27) forms a bridge (31) connecting the first leg and the second leg of the L-shaped current rail (3).

10. The connecting terminal (A, B) of any of the preceding claims, wherein the housing (1) comprises a spring clamp insertion opening which extends along the entire contour of the spring clamp (4) when no conductor (9) is clamped in the conductor clamping region.

11. The connecting terminal (A, B) of claim 10, wherein the first extension (27) covers at least part of the spring clamp insertion opening.

12. The connecting terminal (A, B) of any of the preceding claims, wherein the housing (1) is made of a plastic material.

13. The connecting terminal (A, B) of any of the preceding claims, wherein the spring clamp (4) and/or the current rail are made of a metallic material.

14. A method of manufacturing the connecting terminal (A, B) of claim 10 or 11, comprising the steps of: providing the housing (1); inserting the spring clamp (4) through the spring clamp insertion opening; installing the current rail (3) such that the first extension limits a movement of the spring clamp (4) in a direction perpendicular to the direction of the clamping force.

15. Computer-readable file comprising instructions which, when loaded by a computer, cause a 3D-printer under the control of the computer to print a housing (1) suitable for the connecting terminal (A, B) of any of claims 1 to 13.

Description

[0025] Exemplary embodiments of the invention are described in the following in relation to figures, in which

[0026] FIG. 1 shows a partial view of a connection terminal with a cantilever-style extension of the current rail,

[0027] FIG. 2 shows a partial view of the connection terminal of FIG. 1 with an inserted conductor,

[0028] FIG. 3 shows a full view of a connection terminal with a bridge-style extension of the current rail, and

[0029] FIG. 4 shows a full view of the current rail of the connection terminal of FIG. 3.

[0030] FIGS. 1 and 2 show a schematic partial view of a connecting terminal A, wherein FIG. 1 shows the arrangement without an inserted conductor and FIG. 2 shows the arrangement with an inserted conductor. In FIGS. 1 and 2, only the part of the connecting terminal A comprising the conductor clamping region is shown in order to describe the function of the clamping mechanism. The connecting terminal A has a housing 1 cast as one piece from a plastic material. The housing 1 has an interior clearance 2. In the interior clearance 2 of the housing 1, a current rail 3 and a spring clamp 4 are arranged.

[0031] The current rail 3 is formed from a narrow metal band and bent in the shape of an L. In its state when inserted into the housing 1, as shown in FIG. 1, the current rail 3 is positioned against an interior wall 5 of the housing 1. As can be seen in FIG. 1, the housing 1 has an opening 21 on one longitudinal lateral face, so that the housing is open at the side. The housing 1 is thus open on one side. The current rail 3 is inserted into the housing via this side opening 21. The back side of the housing 1 is completely closed

[0032] The spring clamp 4 is designed in the form of a leg spring with a retention leg 20 and a clamping member 6. The spring clamp 4 is pushed open onto a retention element 7 formed in the housing 1, which retention element 7 is formed integrally with the housing 1. In order to slide the spring clamp 4 onto the retention element 7, the spring clamp 4 is also inserted into the housing 1 via the side opening 21.

[0033] In the housing 1 itself, a conductor inlet opening 8 is formed, via which a conductor 9 to be clamped, as shown in FIG. 2, can be inserted in order to be clamped against the current rail 3 by means of the clamping member 6 of the spring clamp 4.

[0034] Furthermore, the connecting terminal A has a spring guiding surface on its front side in FIG. 1 and FIG. 2 which serves as a guide for the spring clamp 4 during its movement, and also as a guide for the conductor 9 to be clamped. The spring guiding surface comprises two parts that are arranged in a common plane: The first part is a front plastic surface 10 forming an essentially flat wall. The front plastic surface is formed as a cantilever from the bottom and is free to deflect on the top side. The second part of the spring guiding surface is a first metal extension 27 formed as a cantilever which extends perpendicularly from the leg of the L-shaped current bar 3 which is adjacent to the conductor clamping region. The first metal extension 27 is located directly adjacent to the spring clamp 4 and covers the spring clamp 4 from the front side of the housing 1.

[0035] The spring guiding surface comprising the metal extension 27 and the front plastic surface 10 is formed such that it laterally borders, in the direction of the side opening 21 in the housing 1, the conductor clamping region formed between the clamping member 6 and the current rail 3. The clamping member 6 of the spring clamp 4 and the lateral face 13 of the current rail 3, to which the conductor 9 is clamped, are located opposite one another such that the spring guiding surface is arranged off-centre between the clamping member 6 of the spring clamp 4 and the current rail 3. As can be seen in FIG. 2, the conductor 9 to be clamped is inserted from above into the conductor clamping region between the clamping member 6 and the current rail 3, the conductor 9 being guided between the back wall and the metal extension 27. A lateral slipping or sliding of the conductor 9 to be clamped, out of the clamping region, can be prevented.

[0036] Furthermore, the spring guiding surface comprising the metal extension 27 and the front plastic surface 10 acts as a retainer for the spring clamp 4 since the spring clamp 4 is prevented from sliding forwards from the retention element 7. For the first few millimeters of spring displacement when the conductor 9 is inserted, this is achieved by the metal extension 27 since the clamping member 6 of the spring clamp 4 is arranged behind the metal extension 27 and can be activated there by means of the conductor 9 or a release tool, for example a trigger 12. Thus, if the clamping member 6 twists on insertion of the conductor 9, it will be first guided and restricted by the metal extension 27 of the current rail 3. It gets further support from the cantilevered front plastic surface 10. However, the main guiding force comes from the metal extension 27. Due to this, even if the spring clamp 4 twists, it cannot “bite” into the front plastic surface 10 as the metal extension 27 will restrict it. Hence, no structural damage can happen to the front plastic surface 10, thereby ensuring smooth subsequent spring actions.

[0037] The front plastic surface 10 is formed at a distance from the interior wall 5 of the housing 1, such that a clearance or gap 22 is formed between the longitudinal side 14 of the front plastic surface 10, which side points towards the interior wall 5 of the housing 1, and the interior wall 5 of the housing 1 in the clamping direction of the clamping member 6 of the spring clamp, as well as a clearance or gap 23 between the lower side 15 of the front plastic surface 10 and the interior wall 5, formed as the floor surface, of the housing 1 in the conductor insertion direction. The current rail 3 can be inserted into the housing 1 via the gap 22 and the gap 23 between the conductor guide 10 and the interior wall 5 of the housing 1.

[0038] In its inserted state, the current rail 3 is fastened to the housing 1 by a latching mechanism (not shown). The current rail 3 also has a second metal extension 28 located on the lower leg of the L-shaped current rail 3. It is formed just as the first metal extension 27, i.e. as a perpendicular cantilever extending from the current rail in the plane of the spring guiding surface. However, the second metal extension is located adjacent to the tip of the retention leg 20 such that it prevents a side movement of the retention leg 20. From FIG. 1 and FIG. 2, it is apparent that the side opening 21 of the housing 1 comprises the entire contour of the spring clamp 4. Thus, with the current rail 3 and in particular with its two extensions 27, 28 removed, the spring clamp 4 can be easily removed from the housing 1 through the opening 21. However, with the current rail 3 installed, the extensions 27, 28 securely fixate the tips of the clamping member 6 and the retention element 7 in the housing because they cover the opening 21 over these two tips.

[0039] In the housing 1, adjacent to the front plastic surface 10, a spring limiting element 18 is formed, which is integrally moulded with the housing 1. The spring limiting element 18 limits the maximum deflection of the clamping member 6 of the spring clamp 4 (see spring clamp position in FIG. 2) and projects at an angle of substantially 90° relative to the conductor guide, into the interior clearance 2 of the housing 1. As can be seen in FIGS. 1 and 2, the spring limiting element 18 is connected to the front plastic surface 10.

[0040] Referring to FIGS. 1 and 2 and the design of the opening 21 and the extensions 27, 28 described above, the production of the connecting terminal A is described in the following. The housing 1 with all described plastic parts is injection molded or cast or 3D-printed in one piece. To the latter end, a 3D model file is provided to a computer with a 3D printer attached. Then, the spring clamp 4 is inserted via the opening 21. Thereafter, the current rail 3 is inserted so that the extensions 27, 28 fixate the tips of the clamping member 6 and the retention element 20. As a result of these two restrictions the spring clamp 4 can never get dislodged and come out of the plastic housing 1 even when a maximum size conductor is inserted.

[0041] FIGS. 3 and 4 show an alternative embodiment of a connecting terminal B. First, FIG. 3 shows the entire outside contour of the housing 1 which is identical to the contour of the housing 1 of the embodiment of FIG. 1 and FIG. 2. As can be seen, there are two conductor inlet openings 8 and two conductor clamping regions in a basically mirror symmetric arrangement, such that the current rail 3 will have two L-shaped parts which together are U-shaped.

[0042] In the following, the embodiment of FIGS. 3 and 4 is only explained based on its differences to the embodiment of FIGS. 1 and 2. First, the current rail 30 is designed differently: The two extensions 27, 28 of the current rail 3 from FIGS. 1 and 2 are connected integrally by a broad bridge 31 which diagonally links the two legs of the L-shape. As a result, the L-shape is broken and misses the 90° edge part.

[0043] As can be seen in FIG. 3, the broad bridge 31 now entirely forms the spring guiding surface. There is no need and no room for a front plastic surface 10. Instead, the bridge 31 guides the conductor 8 and the spring clamp 4 during operation. The embodiment of FIG. 3 and FIG. 4 provides even better guidance for the spring clamp 4 and a larger metal contact area for the conductor 8.

LIST OF REFERENCE SIGNS

[0044] A, B connecting terminal [0045] 1 Housing [0046] 2 Interior clearance [0047] 3 Current rail [0048] 4 Spring clamp [0049] 5 Interior wall [0050] 6 Clamping member [0051] 7 Retention element [0052] 8 Conductor inlet opening [0053] 9 Conductor [0054] 10 Front plastic surface [0055] 12 Trigger [0056] 13 Lateral face [0057] 14 Longitudinal side [0058] 15 Lower side [0059] 18 Spring limiting element [0060] 20 Retention leg [0061] 21 Opening [0062] 22 Gap [0063] 23 Gap [0064] 26 Clearance [0065] 27 Extension [0066] 28 Extension [0067] 30 Current rail [0068] 31 Bridge