Conductor connection terminal, clamping spring of a conductor connection terminal and terminal block
11605907 · 2023-03-14
Assignee
Inventors
Cpc classification
H01R4/48455
ELECTRICITY
International classification
Abstract
A conductor connection terminal, having an insulating material housing, a busbar, a clamping spring and an operating lever which is pivotably received in the insulating material housing over a pivoting range and can be pivoted between an open position and a closed position, wherein the clamping spring has an operating arm which is deflected via a spring driver of the operating lever at least in the open position, characterized in that the operating lever is supported in the open position at a first and a second support point spaced from the first, and that the operating lever is pulled against the first and the second support point by a tensile force of the clamping spring acting on the spring driver from the operating arm.
Claims
1. A conductor connection terminal comprising: an insulating material housing; a clamping spring; and an operating lever which is received in the insulating material housing such that the operating lever is adapted to pivot over a pivoting range between an open position and a closed position, wherein the clamping spring has a clamping leg and an operating arm projecting from the clamping leg, wherein the operating lever cooperates with the operating arm to move the clamping leg, wherein the operating arm of the clamping spring has a driver area with a driver opening, the driver opening being a through hole that extends directly through the operating arm and the through hole being fully encircled by material of the operating arm, and wherein the operating lever has a spring driver which cooperates with the driver area to move the clamping leg, and in the closed position of the operating lever, the spring driver does not extend into the driver area of the clamping spring, such that the spring driver does not extend through the driver opening in the closed position, and wherein in the open position of the operating lever, the spring driver extends through the driver opening.
2. The conductor connection terminal according to claim 1, wherein the clamping spring has a contact leg that extends through the driver opening in the operating arm.
3. A conductor connection terminal comprising: an insulating material housing; a busbar; a clamping spring; and an operating lever which is pivotably received in the insulating material housing and is adapted to be pivoted over a pivoting range between an open position and a closed position, wherein the clamping spring has a contact leg, a spring arch adjoining the contact leg, a clamping leg adjoining the spring arch with a clamping tongue and an operating arm projecting from the clamping leg, wherein the operating lever cooperates with the operating arm to move the clamping tongue, wherein the operating lever is supported on the busbar at least over a portion of the pivoting range, wherein the operating lever has a first guide section, wherein the busbar has a recess, the recess being a through hole that extends directly through, and is fully encircled by, material of the busbar, and wherein the first guide section of the operating lever dips into the recess in the busbar at least over a portion of the pivoting range.
4. The conductor connection terminal according to claim 3, wherein the operating lever has at least one support projection for supporting the operating lever on the busbar.
5. The conductor connection terminal according to claim 4, wherein the operating lever is guided, at least over a portion of the pivoting range, through the first guide section that dips into the recess in the busbar during the pivoting movement.
6. The conductor connection terminal according to claim 4, wherein the at least one support projection is arranged adjacent to the first guide section on the operating lever.
7. The conductor connection terminal according to claim 3, wherein the recess in the busbar is slot-shaped.
8. The conductor connection terminal according to claim 3, wherein the contact leg is supported on the busbar.
9. The conductor connection terminal according to claim 3, wherein the operating lever is floatingly mounted in the insulating material housing, such that there is no fixed support axis for the operating lever.
10. The conductor connection terminal according to claim 3, wherein the operating arm of the clamping spring has a driver area and the operating lever has a spring driver which cooperates with the driver area to move the clamping tongue.
11. The conductor connection terminal according to claim 10, wherein in the closed position of the operating lever, the spring driver does not touch the operating arm.
12. The conductor connection terminal according to claim 10, wherein the spring driver does not extend into the driver area of the clamping spring in the closed position of the operating lever.
13. The conductor connection terminal according to claim 10, wherein in the closed position of the operating lever, the spring driver is arranged at least partially or completely within the recess of the busbar.
14. The conductor connection terminal according to claim 10, wherein the driver area of the operating arm of the clamping spring has a driver opening, the driver opening being a through hole that extends directly through the operating arm and the through hole being fully encircled by material of the operating arm, wherein in the closed position of the operating lever, the spring driver of the operating lever does not extend through the driver opening and in the open position of the operating lever, the spring driver extends through the driver opening.
15. The conductor connection terminal according to claim 14, wherein the contact leg of the clamping spring extends through the driver opening in the operating arm.
16. The conductor connection terminal according to claim 3, wherein the operating lever is supported on the busbar by at least one support projection of the operating lever being supported directly on a support area of the busbar which faces the operating lever.
17. The conductor connection terminal according to claim 3, wherein the first guide section of the operating lever projects through the recess of the busbar and cooperates with a further element of the conductor connection terminal on a side of the busbar which faces away from the operating lever.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
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DETAILED DESCRIPTION
(25) The conductor connection terminal 1 has an insulating material housing 2, a busbar 3, a clamping spring 4 and, as an operating element for operating the clamping spring 4, an operating lever 5.
(26) The insulating material housing 2 has a conductor insertion opening 20 through which an electrical conductor can be inserted in a conductor insertion direction L1 and guided to a first clamping point 7 of a first conductor connection 6, where the electrical conductor can be clamped by spring force by means of the clamping spring 4 and the busbar 3. The insulating material housing 2 also has a busbar duct 22 through which at least a part of the busbar 3 is guided and is at least partially fixed and/or supported there.
(27) The busbar 3 has a first busbar section 30 and a second busbar section 31. The first busbar section 30 is connected to the second busbar section via a bent area 35, so that the busbar 3 as a whole has a bent and/or angled shape. The second busbar section 31 is arranged at least predominantly within the busbar duct 22. The busbar 3 has a conductor lead-through opening 36 in the first busbar section 30, through which an electrical conductor that is to be clamped can be guided. The conductor lead-through opening 36 can be surrounded by side walls formed on the first busbar section 30, which e.g. can be designed in the form of a material passage 32. For example, the conductor lead-through opening 36 can have wall sections projecting on all sides from the busbar plane, which form the material passage 32.
(28) The clamping spring 4 has a contact leg 40 by means of which the clamping spring 4 is supported against the spring forces introduced by the clamping leg 43. The contact leg 40 can be supported in the first busbar section 30 on the busbar 3. As shown, the support takes place, for example, in that the free end of the contact leg 40 rests against the inside of the conductor lead-through opening 36 and/or the material passage 32. The clamping spring 4 extends from the contact leg 40 further over the spring arch 41 to the clamping leg 43. The operating arm 42 projects from the clamping leg 43, wherein the operating arm 42 is bent at a relatively large angle, for example greater than 45 degrees or greater than or equal to 90 degrees, from the clamping leg 43. The operating arm 42 ends at its free end with a transverse web 48 which, at its end, delimits the driver opening 46, which cannot be seen in
(29) In addition, the clamping leg 43 extends to a clamping tongue 44, which is bent from the clamping leg 43 in the opposite direction than the operating arm 42. The clamping tongue 44 ends at the free end of the clamping leg 43 with a clamping edge 45. The clamping edge 45, together with the busbar 3, i.e. the conductor lead-through opening 36 and/or the material passage 32, forms the first clamping point 7 of the first conductor connection 6 for an electrical conductor to be clamped there. Accordingly, the contact leg 40 and the clamping tongue 44 dip into the conductor lead-through opening 36.
(30) The conductor connection terminal 1 has an operating lever 5 which is predominantly arranged in the area surrounding the insulating material housing 2 and which essentially extends outward with a manual operating section 50, for example an operating handle, where the operating lever 5 can be actuated manually. The first clamping point 7 can be opened or closed by manually operating the operating lever 5. If the operating lever 5 is in the closed position shown in
(31) The conductor insertion direction L1 can be oriented obliquely to the extension direction of the manual operating section 50. Accordingly, an angle can be formed between the extension of the outer surface of the manual operating section 50, which runs approximately flush with the housing surface, and the conductor insertion direction L1. The angle can be relatively small, e.g. in the range of 20 to 60 degrees.
(32) The operating lever 5 is pivotably mounted in the insulating material housing 2. In this case, no fixed support axis is provided, rather the operating lever 5 can also perform certain displacement movements in the course of a pivoting movement from the closed position to the open position and vice versa.
(33) The operating lever 5 has a test recess 51 penetrating the operating lever 5, e.g. in the area of the manual operating section 50. In the closed position, the test recess 51 is essentially aligned with the test opening 23 of the insulating material housing 2. The test opening 23 extends as far as the clamping spring 4, e.g. up to the spring arch 41. If a test pin is inserted through the test recess 51 and the test opening 23, the clamping spring 4 can be electrically contacted in this way and an electrical measurement can be carried out. The clamping spring 4 is fixed via an overload protection element 29, so that a counter support is created for the test pin. In addition, excessive movement and stress on the clamping spring 4 is prevented by the overload protection element 29 in the insulating material housing 2. The overload protection element 29 can be designed as an island-shaped material area of the insulating material housing 2, which is arranged within the spring arch 41.
(34) In the open position, the clamping spring 4 can rest against the overload protection element 29, that is, it can strike against the overload protection element 29 with one or more areas, for example the spring arch 41 and/or the clamping leg 43.
(35) In several respects, the operating lever 5 is guided, mounted and fixed in certain positions such as the closed position and the open position in the conductor connection terminal 1. For this purpose, the operating lever 5 has a first fixing element 52 in the lower area, i.e. the part of the operating lever 5 remote from the manual operating section 50, and a second fixing element 53 in the rear area, i.e. the area facing away from the spring driver 54. The first and/or the second fixing element 52, 53 can be designed as a latching element, for example. The first and/or the second fixing element 52, 53 can be designed as a material projection or cam. The fixing elements 52, 53 can be molded directly onto the material of the operating lever 5. The operating lever 5 also has a first guide section 57 via which the operating lever 5 is guided in a pivoting movement, in particular in the busbar 3, and is secured against tilting sideways. The first guide section 57 runs through a recess 33 in the busbar 3, for example a recess 33 in the first busbar section 31. The recess can be designed as a longitudinal slot, for example. If the operating lever 5 is pivoted, for example from the closed position to the open position, the first guide section 57 runs through this recess 33. It can also be provided that during a pivoting movement, the operating lever 5 runs along an inner guide contour of the insulating material housing with the second fixing element 53 and is additionally supported and/or guided by this.
(36) As mentioned, the operating lever 5 is used to actuate the clamping spring 4. For this purpose, the operating lever 5 has a spring driver 54, which is shaped like a driver tooth and in the assembled state projects from the operating lever 5 in the direction of the clamping spring 4, in particular in the direction of the operating arm 42. Here, the spring driver 54 is initially not in engagement with the operating arm 42 in the closed position, so that in this closed position no spring load acts on the operating lever 5. The spring driver 54 can be located, for example, in the region of the bent area 35 of the busbar 3, at least in the closed position. The spring driver 54 merges at a bent inner contour of the operating lever 5 into a support area of the operating lever 5, which in this case forms a socket support 59. As will be explained below, this socket support 59 interacts with the bent support area 49 of the clamping spring 4 when the operating lever 5 is pivoted.
(37) The operating lever 5 is fixed in the closed position shown in
(38) A guide element 95 is also formed on the insulating material housing 2. The guide element 95 forms, at least in certain operating situations and/or pivoting positions of the operating lever 5, a housing-side guide for the operating arm 42. For example, at least temporarily during a pivoting movement of the operating lever, the operating arm 42 can slide along the guide element 95 into the open position.
(39) The conductor connection terminal 1 seen in
(40) As a further feature of the insulating material housing 2,
(41) It can also be seen that the outer surface 65 of the manual operating section 50 runs essentially parallel to the second busbar section 31 and/or the third busbar section 37, which will be explained below.
(42) First of all, the mode of operation of the operating lever 5 during a pivoting process will be explained with reference to
(43) The enlarged detail A, B and C shown in
(44) It can be seen from the
(45) The
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(47) The operating lever 5 is located in each operating position, predominantly within the area surrounded by the outer contour 27 of the insulating material housing 2. In particular, the operating lever 5 is also in the open position in a substantial area of its longitudinal extent, not less than at least 30% or at least 40%, within the area surrounded by the outer contour 27 of the insulating material housing 2. In this way, the operating lever 5 is mounted in a particularly robust manner and therefore cannot be damaged so easily and/or cannot tilt so easily. A robust support of the operating lever 5 in the insulating material housing 2 is achieved.
(48) As shown in the enlarged detailed representations in the enlargements D and E, as shown in
(49) With the opposite movement of the operating lever 5, i.e. from the open position to the closed position, the contact between the fourth fixing element 64 and the bent area 35 on the busbar 3 is eliminated at the second support point 85 by the second fixing element 53 sliding up over the first latching edge 21 (see also,
(50) Thus, in the open position, the position of the operating lever 5 can be secured via a two-point support of the operating lever 5 on the insulating material housing 2 and/or the busbar 3 and the essentially central force application of the clamping spring 4 via the operating arm 42. This type of force transmission creates a kind of funnel shape of the force effects, by means of which the operating lever 5 is secured particularly reliably against undesired changes in position, for example due to vibrations.
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(54) Between the contact leg 40 and/or the spring arch 41 and an inner area of the insulating material housing 2, in which the second guide section 55 is arranged in the closed position and the spring driver 54 in the open position, there is a partition 26 of the insulating material housing 2, which has the second latching edge 91. This partition 26 provides an additional separation between the operating lever 5 and the electrical components, in particular the clamping spring 4.
(55) Another positive aspect of this construction is that the partition 26 is in turn supported and counter-supported by the clamping spring 4 against the support force of the operating lever 5 at the first support point 84, since the clamping spring 4 in the area of the contact leg 40 and/or the spring arch 41 presses from the opposite side against the partition 26. In this way, a self-supporting system can advantageously be created. In addition, a plastic component is supported in this way against a metal component, which induces or introduces the force, which is advantageous when exposed to moisture that can lead to a reduction in the stability of the plastic material.
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(57) It can also be seen that the operating lever 5 is supported by laterally projecting shoulder-shaped support projections 58 on the upper side of the busbar 3, in particular in the second busbar region 31. In particular in the open position, the support projection 58 can form a support point for the operating lever 5 on the busbar 3, wherein the support point can be arranged in the bent area 35.
(58) The first fixing element 52 can also run along an inner guide contour of the insulating material housing during a pivoting movement of the operating lever 5, for example during a pivoting movement from the open position into the closed position. In this case, the contact between the support projection 58 on the operating lever 5 and the support area 34 can be eliminated, which is used to support the movement of the operating lever 5 in the direction of the open position, wherein the operating lever 5 is lifted from the busbar 3. Among other things, this also serves to reduce wear or abrasion on the operating lever 5.
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(61) In the open position, the lever lead-through slot 25 is largely closed by the area of the operating lever 5 that has the spring driver 54, so that protection against contact is also ensured in this position.
(62) Generally speaking, there is an opening in the insulating material housing 2, such as the lever lead-through slot 25, which is covered by the operating lever 5 in the closed position of the operating lever 5 and is thus shielded from the outside environment, wherein the opening leads to electrically active components arranged in the insulating material housing 2 such as the clamping spring 4 or busbar 3, and the spring driver 54 in the open position of the operating lever 5 at least partially closes this opening, at least to the extent that contact protection is provided.
(63) The previously explained elements of the operating lever 5 are also illustrated by the various representations in
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(65) As is also made clear, the operating lever 5 can be designed as a material and weight-optimized component with a series of recesses that are interrupted by reinforcing walls and in this way ensure the necessary robustness and rigidity of the operating lever for the operating movements. The operating lever 5 can, for example, be made in one piece as a plastic component, e.g. as an injection-molded part.
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(69) The lever opening 88 can be completely surrounded on the circumference by the material of the insulating material housing 2, i.e. by corresponding walls or other sections of the insulating material housing 2.
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(72) Since the side webs 47 can be designed like “thin legs”, they act like a type of flexible connecting element, i.e. like a thread or rope connection when subjected to tensile load. A relatively small bending radius R3 at the transition from the operating arm 42 to the clamping leg 43 or the narrow bend formed thereby causes a stiffening in this area, so that the side webs 47 are quasi stretched under the tensile load that occurs and experience almost no elastic deformation in the form of a deflection.
(73) The clamping spring 4 can be designed in one piece with all the features described, that is to say made integrally from a flat sheet of metal, e.g. punched from a sheet metal with a predetermined thickness and bent.
(74) It can also be seen in
(75) The clamping tongue 44 can in particular be trapezoidal or can become narrower towards the free end. This has the advantage that if the clamping spring 4 is positioned at an angle, the clamping spring 4 does not block on the inner side surfaces of the material passage 32.
(76) The operating arm 42 has the transverse web 48 at the end. A bent tab 93 projects from the transverse web 48. On the underside, i.e. on the side facing the driver opening 46, the tab 93 forms the bent support area 49 for resting on the socket support 59 of the operating lever 5. The operating arm 42 can be produced in the end area in such a way that the area with the transverse web 48 is bent in a first bending direction from the side webs 47 and the tab 93 is bent from the transverse web 48 in another, opposite bending direction. In this way, while avoiding excessive degrees of deformation, a relatively large angle exceeding 90 degrees can be achieved between the tab 93 and the side webs 47.
(77) Accordingly, the operating arm 42 has two side webs 47, which are spaced apart from one another and which are connected to one another at their free end via the transverse web 48. The side webs 47 and the transverse web 48 enclose the driver opening 46, which is used to engage the spring driver 54. The tab 93, which points into the driver opening 46 and has a bend, adjoins the transverse web 48 so that this bend forms a bent support area 49 on its convex surface, which is designed for contact with the socket support 59 of the operating lever 5.
(78) Accordingly, the free end of the operating arm 42 is bent away from the spring arch 41 with the transverse web 48. The curvature or rounding of the bent support area 49 is adapted to the shape of the socket support 59 in terms of shape.
(79) It can also be seen that the operating arm 42 branches off from the clamping leg 43 relatively far at the end of the clamping leg 43, but at the very least closer to the clamping edge 45 than on the spring arch 41. The operating arm 42 thus runs at a minimal distance from the busbar 3 (also see
(80) The clamping spring 4 can be designed to be particularly elastic. This configuration also prevents the clamping spring from tilting significantly in the event of a diagonal pull.
(81) The operating arm 42 can also be guided by guide means in the insulating material housing, for example, an inner housing wall or housing edge, in the longitudinal direction of the operating arm 42. Such an inner housing edge is formed, for example, by the free end of the intermediate wall 26 extending into the interior of the insulating material housing 2 (see also
(82) The distance, that is to say the gap between the operating arm 42 and the busbar 3, can for example be less than 1 mm, or less than 0.5 mm. An exemplary advantageous value is 0.3 mm. In this way, the operating arm 42 does not yet touch the busbar, so that wear due to friction is avoided.
(83) According to an advantageous embodiment, the effective length of the operating arm 42 with regard to the actuation, measured from the junction of the operating arm 42 from the clamping leg 43 to the bent support area 49, is greater than the length of the clamping leg, measured from the junction of the operating arm 42 from the clamping leg 43 to the vertex of the spring arch 41. In this way, a spring with a short buckling length and favorable operating forces can be realized.
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(85) As
(86) It can also be seen that the operating arm 42 essentially does not change its position with respect to the clamping leg 43 in the course of the operating movement of the operating lever 5. This has the advantage that the transition point between the operating arm 42 and the clamping leg 43 is only exposed to slightly changing bending loads during use. This is further supported by a comparatively small bending radius at the transition from the operating arm 42 to the clamping leg 43. For example, a mean bending radius R3 of this bending area, which is at most three times the thickness of the sheet metal, is favorable. This enables the force of the operating lever 5 to be optimally introduced into the clamping spring 4 via the operating arm 42. This results in direct transmission, a short stroke and, as a result, essentially no stretching in the operating arm 42. In addition, such a construction allows for the components used and the entire conductor connection terminal 1 to be manufactured easily.
(87) The clamping spring 4 can thus be arranged with its predominant parts and in particular with the operating arm 42 on one and the same side of the busbar 3, in particular on the side from which an electrical conductor is inserted into the conductor lead-through opening 36.
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(89) The first and second busbar sections 30, 31 have the elements already described. In particular, the recess 33 for guiding the first guide section 57 and the support areas 34 for supporting the support projections 58 of the operating lever 5 can be seen. The recess 33 can be arranged only in the second busbar section 31 or, as shown, also extend into the bent area 35 or even as far as the first busbar section 30. The recess 33 is enclosed on all sides by the material of the busbar 3. It can be designed as a recess that only partially penetrates the material of the busbar from the side of the support area 34 or as a completely continuous recess (without a bottom).
(90) The busbar 3 is angled and/or bent by the bent area 35, i.e. in such a way that an angle is formed between the first busbar section 30 and the second busbar section 31. The bent area 35 can form an interior angle between the first busbar section 30 and the second busbar section 31 in a range from 105 to 165 degrees or 120 degrees to 150 degrees. The bent area 35 can be designed, for example, in such a way that the busbar 3, starting from the second busbar section 31, is initially bent concavely with a first radius R1 and then merges into a convex bent section with a radius of curvature R2, in each case in one viewing direction onto the support area 34. It is advantageous if the radius R1 is larger than the radius R2, for example, at least twice as large.
(91) In this way, the operating lever 5 can at least partially also be supported on the bent area of the busbar 3, i.e. in the bent area 35, and can run along it during a pivoting movement.
(92) As an alternative to the one-piece design exemplified thus far, the busbar 3 described can also be designed as a multi-piece design, e.g. with two or more separate busbar sections. In particular, the third busbar section 37 can be designed as a separate busbar section from the first and second busbar sections 30, 31. This is, e.g., advantageous for use in a disconnect terminal.
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(94) The conductor connection terminals 1 have support rail fastening elements 82 with which the respective conductor connection terminal 1 can be fastened to a support rail, for example by snapping it onto the support rail. Relative to a fastening plane of the conductor connection terminal 1 defined by the support rail, the conductor insertion direction L1 can be arranged, for example, in a range of 30 degrees to 60 degrees to the fastening plane, and the conductor insertion direction L2 in an angular range of 75 to 105 degrees.
(95) The support rail fastening elements 82 are arranged on a support rail fastening side of the insulating material housing 2. The operating levers 5 can be seen on the housing side of the insulating material housing facing away from the support rail fastening side, which is also referred to as the housing upper side 83. Here, the outer surface 65 of the manual operating section of the operating lever 5 in the closed position has the same course as the adjacent surface contour of the insulating material housing, i.e. the adjacent parts of the housing top side 83.
(96) The conductor connection terminal 1 in the area of the second conductor connection 8 can be actuated by a further operating element 81, which can be arranged either as part of the conductor connection terminal 1, e.g. in the form of a pusher, in an operating opening 80 of the insulating material housing 2, or can be implemented by a separate operating tool that can be guided as needed through the operating opening 80 to the second conductor connection 8, but which is not part of the conductor connection terminal 1.
(97) A further embodiment of the clamping spring 4 and a conductor connection terminal 1 formed therewith are shown using
(98) It can also be seen that the clamping spring 4 according to
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(100) A straight connecting line 86 is shown in
(101) Based on the sequence of movements of the operating lever 5 illustrated by
(102) First of all, it is assumed that the operating lever 5 is completely in the open position and is supported on the first support point 84 and the second support point 85, as shown in
(103) If the operating lever 5 is now subjected to force by the action of a manual operating force on the operating section 50 in the direction of the closed position, the pivoting process of the operating lever 5 begins with a first instantaneous center M1 of the pivoting movement being formed at the first support point 84, i.e. between the second latching edge 91 and the first fixing element 52. A second location of the main contact point K2 can now be formed at the first support point 84. At the same time, the latching at the second support point 85 is released, i.e. the operating lever 5 is slightly raised in this area so that the fourth fixing element 64 and its adjoining material areas are not stressed by friction on the busbar 3 and are accordingly not worn. As a result of this movement phase of the operating lever 5, the second fixing element 53 can concurrently be lifted over the first latching edge 21, so to speak, wherein a certain distance can arise between the second fixing element 53 and the first latching edge 21.
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(105) The contact between the lateral support element 56 and the insulating material housing 2 is again broken. The operating lever 5 can now slide along a guide track of the insulating material housing with the second fixing element 53 or the underside of the first guide section 57, so that a fourth location of the main contact point of the operating lever 5 is now formed at this location.
(106) Furthermore, in the further course of movement, the support projection 58 of the operating lever 5 comes into contact with the support area 34 of the busbar 3, so that a fifth location of the main contact point of the operating lever can be formed between the support area 58 of the operating lever 5 and the support area 34 of the busbar.
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(108) The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.