ARRANGEMENT CONSISTING OF AT LEAST ONE CLAMPING SPRING, ONE RETAINING SPRING, AND ONE SPRING-FORCE CLAMP FOR LADDERS

Description

[0001] The present invention relates to an arrangement comprising a clamping spring and a retaining spring, as well as a spring-loaded terminal as an arrangement comprising the clamping spring with a busbar, which is provided for contacting an electrical conductor, in particular a stranded conductor.

[0002] Spring-loaded terminals in a design as direct plug-in terminals (push-in) with a compression spring that presses the conductor against the busbar are known in a wide variety of designs.

[0003] It is known, for example, to lock clamping springs - compression springs - in an open position so that a conductor can be easily guided into a contact area. According to prior art, this locking of the clamping spring in an open position is achieved by an actuating means such as a push-button that can be locked onto the terminal housing, whereby the push-button holds the clamping leg in an open position. By releasing the actuating means after the conductor has been inserted, the clamping leg can relax and press the conductor against the busbar. A disadvantage is that the actuating means must be released manually to make contact with the conductor.

[0004] From DE 10 2019 132 316 A1, a spring-loaded terminal of this type is known in which the wear of the clamping edge of the clamping spring is reduced and incorrect insertion or premature release of the clamping spring is effectively prevented.

[0005] However, there is a need to adapt the spring constant of the aforementioned clamping spring to achieve a stronger clamping force for certain applications. Practical tests have surprisingly shown, however, that increasing the spring constant through thermal treatment is accompanied by a significant increase in friction coefficients, which makes it more difficult to trigger the clamping mechanism.

[0006] Based on the aforementioned prior art, the object of the present invention is to achieve an adaptation of the generic spring-loaded terminals to higher clamping forces without hindering / impairing the (triggering) mechanism of the spring-loaded terminal.

[0007] An arrangement according to the invention comprises a clamping spring acting as a compression spring for securing an electrical conductor in a spring-loaded terminal. The spring-loaded terminal need not be part of the arrangement according to the invention, but rather serves to describe the function of the clamping spring.

[0008] Furthermore, the arrangement according to the invention comprises a retaining spring for locking the clamping spring in an open position, so that the conductor can be inserted into a contact area of ​​the spring-loaded terminal in a sliding direction.

[0009] The clamping spring and the retaining spring touch each other along a contact surface in the locked state and during movement from the locked state R to an unlocked state E.

[0010] According to the invention, the contact surface has a lubricant-containing coating. Typically, a contact terminal does not require such coatings, especially since the electrical contact between the conductor and the spring terminal is made more difficult by a lubricant.

[0011] However, the lubricant-containing coating specifically achieves a reduction in the coefficient of friction in the area of ​​the locking mechanism, which advantageously counteracts the triggering of the clamping effect even after starting and the associated undesirable increase in the coefficient of friction due to thermal treatment to increase the spring force.

[0012] Further advantageous embodiments of the invention are the subject of the dependent claims and the following description.

[0013] Advantageously, the contact surface can comprise both a stop surface between the retaining spring and the clamping spring, as well as the adjacent area of ​​the retaining spring over which the contact spring slides during the unlocking movement.

[0014] The lubricant-containing coating can advantageously contain a perfluoropolyether, also known as PFPE. This material is long-lasting and exhibits only marginal changes in viscosity and adhesion during continuous use.

[0015] Preferably, the lubricant-containing coating contains more than 75 wt.%, preferably more than 85 wt.%, of a PFPE, preferably a hexafluoropropene.

[0016] The lubricant-containing coating may also contain a solvent, preferably a base oil, particularly preferably less than 20 wt.%. This can be used to adjust a preferred viscosity and / or density.

[0017] The applied lubricant can advantageously have a density between 1.55-1.75 g / cm 3 (at 20°C) for a surface distribution.

[0018] In one embodiment of the invention, the arrangement can have an uncoated surface adjacent to the contact surface with a higher, preferably on average at least 50% higher, friction coefficient than the contact surface. The area provided with the lubricant-containing coating can preferably be less than 300% of the contact surface, preferably less than 150% of the contact surface. In particular, a contact surface with the electrical conductor can be designed without a coating.

[0019] Preferably, the arrangement is designed as a one-piece component.

[0020] Furthermore, the assembly can be heat-treated to increase the spring constants of the individual elements of the assembly. This is visible through surface coloration caused by tempering.

[0021] Furthermore, according to the invention, a spring-loaded terminal designed as a direct plug-in terminal for connecting a conductor, in particular a stranded conductor, which has an arrangement according to the invention and which has at least the following: a. a busbar for contacting an electrical conductor; b. the clamping spring of the arrangement acting as a compression spring for fixing the electrical conductor in the spring-loaded terminal, c. the retaining spring for locking the clamping spring in an open position so that the conductor can be inserted into a contact area in a sliding direction, d. wherein the clamping spring has a clamping leg pivotable in a pivoting direction with a clamping edge and the retaining spring has a pivotable pivoting leg, e. wherein the pivoting leg has at least one holding means and the clamping leg has a locking means which interacts with the holding means of the pivoting leg in the latching state R of the clamping leg, f.wherein the clamping leg can be adjusted from a latching state R, in which it is latched in the open position by the holding means of the pivoting leg, into a clamping state K by moving the electrical conductor, in which the clamping leg is unlatched from the holding means and presses the electrical conductor with the clamping edge of the clamping leg against the busbar, wherein g. the latching means of the clamping leg is designed to be spaced apart from the clamping edge of the clamping leg.

[0022] It is advantageous if the spring-loaded clamp further comprises a return means for pivoting back the clamping leg, with which the clamping leg can be pivoted back from the clamping state into the locking state by moving the return means against the pivoting direction.

[0023] The return means or a surface for guiding the return means may also have the lubricant-containing coating.

[0024] Also advantageous is a terminal block or a connector with one or more spring-loaded terminals according to the invention.

[0025] A method for producing a device according to the invention comprises the following steps: a) Shaping the assembly or at least individual components, in particular at least the retaining spring of the assembly; b) Thermally tempering the component, preferably at temperatures of more than 250°C; c) Coating at least part of the component with the lubricant-containing coating.

[0026] Further advantageous embodiments, more concrete descriptions and advantages of the spring-loaded terminal according to the invention are explained below.

[0027] A spring-loaded terminal for connecting a conductor, in particular for connecting a stranded conductor, is provided, which has a busbar for contacting an electrical conductor and a clamping spring acting as a compression spring for fixing the electrical conductor in the spring-loaded terminal, and a retaining spring for locking the clamping spring in an open position so that the conductor can be inserted into a contact area in a sliding direction.

[0028] The clamping spring has a clamping leg with a clamping edge that can be pivoted about a first pivot axis in a pivoting direction, and the retaining spring has a pivoting leg that can be pivoted about a second pivot axis, the pivoting leg having at least one retaining means. The clamping spring and the retaining spring can be designed as a single piece, which is particularly cost-effective, but can also be manufactured separately and then joined together, with the spacing of the locking mechanism from the clamping edge having an advantageous effect in each case.

[0029] It is further provided that the pivoting leg has at least one holding means in the sense of a first latching means and the clamping leg has a (counter-)latching means which interacts with the holding means of the pivoting leg in the latching state R of the clamping leg, wherein the clamping leg can be adjusted from a latching state R, in which it is latched to the pivoting leg by the holding means of the latter and is held in the open position or conductor insertion position, by moving the electrical conductor into a clamping state K, in which the clamping leg is unlatched from the holding means and presses the electrical conductor with the clamping edge of the clamping leg against the busbar, so that the conductor contacts the busbar.

[0030] Furthermore, the locking means of the clamping leg is designed to be spaced apart from the clamping edge of the clamping leg.

[0031] This design thus creates a spring-loaded terminal which divides the locking mechanism of the clamping spring into a separate locking means and a clamping edge, geometrically and functionally separate from this function, for clamping the conductor against a busbar, in an advantageous functional separation on the clamping spring - in particular on its clamping leg - and which also advantageously reduces wear on the clamping edge of the clamping spring through the functional separation of the contact edge and the locking means.

[0032] It is therefore advantageous that the holding means of the pivoting leg is not directly locked to the clamping edge of the clamping leg.

[0033] This prevents the retaining element from rubbing against the clamping edge when it is released. This simply protects the clamping edge from excessive wear caused by a wiring process.

[0034] It can also be advantageous to prevent incorrect insertion or premature release of the clamping spring, as the locking mechanism is not located in the conductor insertion area.

[0035] In terms of construction, this can be implemented, for example, by the locking means of the clamping leg being formed on the clamping leg at a distance of more than 1 mm, in particular more than 3 mm, from the clamping edge of the clamping leg.

[0036] It can advantageously be provided that the spring-loaded clamp also comprises a return means for pivoting back the clamping leg, with which the clamping leg can be pivoted back from the clamping state into the locking state R by moving the return means against the pivoting direction,

[0037] To achieve an advantageously simple design for the clamping spring, the clamping spring can be formed integrally with the retaining spring. This results in a simple assembly process for the clamping spring and cost-effective production.

[0038] However, it can also be provided that the spring-loaded terminal has a separate retaining spring in addition to the clamping spring, whereby the clamping spring and the retaining spring can, however, be connected to one another by a connection.

[0039] According to a further preferred embodiment of the invention, the clamping spring can have a support leg with which it is supported on a corresponding abutment.

[0040] The abutment can be a leg of the busbar. However, it can also be the terminal housing.

[0041] The fact that the retaining spring can have a pressure surface arranged transversely to the sliding direction creates a simple, effective, and thus advantageous way for the clamping spring to be released through the conductor end. It is also advantageous if the retaining means is integrally formed onto the pivoting leg. This results in a simple structural implementation of the retaining means on the pivoting leg.

[0042] According to a further preferred embodiment of the invention, the pivoting leg can be angular. It is also advantageous if the pressure surface is connected to a first, downwardly curved leg of the pivoting leg. This further simplifies the design of the connecting device. It can also be advantageous for the clamping leg to form a kind of angular shape, as this increases the design possibilities from a geometric perspective.

[0043] It is also advantageous if, in one variant, the retaining means of the pivoting leg is formed by a locking edge arranged at the end of a second, upwardly curved leg of the angled pivoting leg. This results in a simple structural implementation of the retaining means on the pivoting leg.

[0044] In another variant, the retaining element of the pivot arm can also be designed as a flared tab on the pivot arm. This design results in a simple and therefore advantageous structural implementation of the retaining element on the pivot arm.

[0045] In a further preferred embodiment of the invention, the retaining means of the pivoting leg can be designed as at least one hook or at least one web and formed integrally with the pivoting leg. This again results in an advantageously simple structural design of the retaining means.

[0046] Particularly advantageous - as they are compact and can be implemented without large waste - are variants in which the respective hook is cut out of the material of the swivel leg at the side or in the middle and is bent out of this and serves to engage behind a corresponding edge or tab or the like on the clamping leg, which is located at a distance from the clamping edge in a recess or hole in the clamping leg.

[0047] Because the first, downwardly bent leg and the second, upwardly bent leg can be connected to one another in one piece by a bend, the rigidity of the pivoting leg of the retaining spring is advantageously increased by simple structural means.

[0048] In a further preferred embodiment of the invention, the pivoting leg of the retaining spring can have an opening in the region of the second, upwardly bent leg of the bend and the first downwardly bent leg, into which the clamping leg engages in the locking position R of the clamping leg. This results in an advantageously space-saving design of the retaining spring, and furthermore, an advantageously increased clamping force of the clamping spring results.

[0049] It is also advantageous if the opening has a narrowing in the area of ​​the retaining means and the bend of the pivoting leg of the retaining spring. This allows for a simple design of a locking means on the clamping leg of the clamping spring.

[0050] It is also advantageous if the clamping leg has a tapered section that geometrically corresponds to the constriction, so that the clamping leg can move freely through the opening in the pivoting leg, for example. This results in a space-saving design for the retaining spring.

[0051] In a further preferred embodiment of the invention, the locking means of the clamping leg can be integrally formed on the clamping leg or formed with it. This results in a simple structural implementation of the locking means on the clamping leg.

[0052] It is also advantageous if the locking means of the clamping leg protrudes from the clamping leg and is integrally connected to it. This locking means can be designed, for example, as a section of a hole or a recess, as a web, or as a hook.

[0053] It can further be provided that the locking means of the clamping leg is designed as a tab formed by the waist of the clamping leg and is therefore not flared. This also results in a simple structural design of the locking means.

[0054] Furthermore, it is advantageous if the locking means of the clamping leg is designed as a curved tab and is integrally formed on the outside of the clamping leg.

[0055] In a further preferred embodiment of the invention, the support leg of the clamping spring can have a slot-like opening arranged on both sides along a symmetry line of the support leg. The length and width of the slot allow the rigidity of the support leg to be advantageously and easily adjusted to the respective requirements using simple structural design means.

[0056] It is also advantageous if, according to a variant, the pivoting leg has a cutout which is delimited by the holding means of the pivoting leg.

[0057] In a further preferred embodiment of the invention, the return means can be arranged between the clamping spring and the electrical conductor in the latched state and can be displaced in and against the sliding direction. This results in an advantageously simple return of the clamping spring from the latched state.

[0058] It is also advantageous if, according to one variant, the return means is clamped between the clamping leg and a terminal housing in the clamped state. This results in a self-reinforcing clamping effect of the return means in the clamped state of the spring-loaded terminal, using simple means and thus advantageously.

[0059] It is also advantageous if the return mechanism can be moved in the sliding direction according to a variant for returning the clamping leg. This results in an easy-to-use and safe return process for the clamping leg.

[0060] According to another advantageous variant, a stop element can be applied to the retaining spring, on which the pressure surface is formed. The stop element – ​​possibly with the bead – has the advantage that it can be more optimally designed with the desired geometry through the injection molding process than if it were incorporated directly into the pressure surface of the spring, because the spring material only allows for a limited 'forming process'.

[0061] According to a further preferred embodiment of the invention, the pressure surface can have a bead-like recess. This bead-like recess easily bundles / centers the strands during wiring to minimize strand splitting. Additionally, the force at which the strands split can be increased.

[0062] It is therefore advantageous if the pressure surface, according to one variant, has a self-centering effect thanks to the bead-like recess for the conductor or its core. This ensures reliable function of the pressure surface thanks to a particularly simple design.

[0063] The invention also relates to a terminal block or connector with one or more spring-loaded terminals according to one or more of the claims related thereto.

[0064] Further advantageous embodiments of the invention can be found in the subclaims.

[0065] The invention is described in more detail below with reference to the drawings. They show: Figure 1: a spatial view in section of a spring clamp according to the invention with a clamping leg in the latching state, which is provided for clamping an electrical conductor inserted into the spring clamp; Figure 2: a spatial view of a clamping spring for use in an alternative spring clamp according to the invention in a modification of Figur 1 in a state before assembly; and Figure 3: a diagram showing test results for improving the friction coefficient after tempering.

[0066] Fig. 1 shows a spring-loaded terminal 1 as a connection device for electrical conductors. The conductors to be connected, particularly in the plug-in direction 7, are designed, in particular, as stripped conductor ends. These conductor ends can also be designed as fine-stranded conductors or stranded conductors. However, the spring-loaded terminal is also suitable for solid conductors.

[0067] The spring-loaded terminal can be used in various ways, for example as a connection device for a terminal block or as a spring-loaded terminal for connectors or the like.

[0068] The spring-loaded terminal 1 has a busbar 2 for contacting an electrical conductor 6. The busbar 2 can be L-shaped. However, it can also be part of a multi-walled clamping cage. The clamping cage can be U-shaped in plan view, so that a conductor end can be inserted into the cross-section of the U, and can also have a lower transverse wall. The spring-loaded terminal 1 then has a clamping spring 3 acting as a compression spring, which is provided for clamping the electrical conductor 6 in the spring-loaded terminal 1, whereby the electrical conductor 6 permanently contacts the busbar 2 in an electrically conductive manner. The clamping spring 3 thus serves to press the conductor 6 against the busbar 2.

[0069] In addition to the clamping spring, a retaining spring 4 is provided. This serves to lock a part of the clamping spring 3, namely a clamping leg 32, in an open position, so that the conductor 6 can be inserted into an insertion opening 11 of the spring-loaded terminal 1 up to a contacting area when the clamping spring is in the open and tensioned state. The clamping spring 3 can be designed as one piece with the retaining spring 4. However, the retaining spring 4 can also be manufactured separately from the clamping spring 3. The retaining spring 4 can then be connected to the clamping spring 3. Preferably, the "clamping spring arrangement" according to Fig. 1 A component is created that integrates the function of the clamping spring 3 and the function of the retaining spring 4 into a single component—i.e., in one piece. This functionally integrated design of the clamping spring 3 with the integrally formed retaining spring 4 is advantageous, but not mandatory.

[0070] The busbar 2 and the clamping spring 3 are arranged in the terminal housing 12, which is preferably made of an electrically insulating material, in particular of a plastic. An insertion opening 11 for inserting the electrical conductor 6 is provided in the terminal housing 12. The electrical conductor 6 shown has an electrically insulating sheath 62, which is stripped above an open end 63 of the electrical conductor 6, so that a wire 61 of the electrical conductor 6 is visible. The clamping spring 3 has a clamping leg 32 that can be pivoted about a pivot axis 8 in and against a pivot direction 81, as well as a support leg 31, with which it is supported in a simple and secure manner on a corresponding abutment, in particular when the clamping leg 32 is pivoted. This abutment can be designed as a support leg 21. This can be formed integrally on the busbar 2 or be bent out of it.However, in other embodiments, the support leg 31 can also be supported in a different way, for example directly in the terminal housing 12.

[0071] The support leg 31 here has a centrally arranged retaining tab 311. This can be bent out of the support leg 31. The retaining tab 311 is supported here on the abutment, here on a corresponding support means, here an abutment leg 21. Preferably, the support leg 31 and the clamping leg 32 of the clamping spring 3 are connected to one another via a bend 30. An advantageous support contour 14 of the terminal housing 12 can engage in this bend 30, which is penetrated here by the rotation axis 8 and which can also serve as a movement limiter for the clamping leg 32. The clamping spring 3 is designed approximately V-shaped overall.

[0072] Extending to the side of the retaining tab 311 are two connecting legs 312a, 312b, which serve as connecting means to the retaining spring 4, which is integrally connected to the clamping spring 3. However, the retaining spring 4 could also be attached to the clamping spring, for example, to the support leg 31 as a separately manufactured component, thus being attached to the support leg 31. The connecting legs 312a, 312b form an angled, in particular approximately right-angled, bend to the retaining spring 4.

[0073] The retaining spring 4 then has a pivoting leg 41. This pivoting leg 41 is curved for structural reasons and has a pressure surface 42 at the end, which the conductor end strikes upon insertion, allowing it to move the pivoting leg 41.

[0074] The pivoting leg 41 is thus designed to pivot resiliently relative to the clamping spring 3, in particular relative to its supporting leg 31. The pivoting leg 31 can be connected to / molded onto the two connecting legs 312a, 312b, or is integrally formed therewith.

[0075] The retaining spring 4 or its pivoting leg 41 is / are pivotable about a second pivot axis 9 in and against a second pivoting direction 91. In order to be able to pivot the clamping leg 32 in the second pivoting direction 91, the retaining spring 4 has the pressure surface 42, with which the pivoting leg can be pivoted. The pressure surface 42 can be arranged transversely to the sliding direction 7. By exerting pressure on the pressure surface 42, the retaining spring 4 can be pivoted in the second pivoting direction 91. The pressure surface 42 adjoins a first, downwardly bent leg 411 of the pivoting leg 41. One or more holding means 412 are formed on the pivoting leg 41, preferably integrally formed on the pivoting leg 41. The holding means 412 are here two locking edges arranged approximately at the end of a second, upwardly bent leg 413 of the angular pivot leg 41.The first, downwardly bent leg 411 and the second, upwardly bent leg 413 are integrally connected to one another by a bend 414.

[0076] The clamping leg 32 of the clamping spring 3 has at least one or more locking means 322. This one or more locking means—here two—is / are spaced from a clamping edge 321—here approximately halfway along the longitudinal extent of the clamping leg. The one or more locking means are designed to be locked to the holding means 412 of the pivoting leg 41 of the retaining spring 4, whereby the clamping leg can in turn be locked in an open position (called the locked state). The locking means 322 are preferably spaced more than 1 mm, in particular more than 2 mm, from the clamping edge 321, so that it cannot be damaged when the terminal is connected to and disconnected from a conductor. The locking means 322 are not operatively connected to the clamping edge 321, i.e., they cannot be locked to it, so that they cannot damage the clamping edge during use.Rather, the locking means 322 are operatively connected to the holding means 412, so that the clamping edge is not locked.

[0077] The locking means 322 can be integrally formed on the clamping leg 32. They can protrude from the clamping leg 32 or be formed therein as a recess or step. They form a locking connection with the retaining means 412 of the pivoting leg 41 of the retaining spring 4 when the clamping leg 32 is in the locked state. Thus, the clamping spring 3 can be locked in an open position, from which it is released upon insertion of the conductor.

[0078] The pivoting leg 41 has an opening 415 in the region of the second, upwardly bent leg 413—that is, an extension of the connecting legs 31a, 31b—the bend 414, and the first downwardly bent leg 411, into which the clamping leg 32 can engage in the locking position R of the clamping leg 32. The opening 415 has a constriction 416 in the region of the holding means 412 and the bend 414. This ensures a compact design.

[0079] The clamping leg 32 accordingly has a geometrically corresponding waist 323, which here directly adjoins the locking means / locking edges 322, so that the clamping leg 32 can move freely through the opening 415.

[0080] When the retaining spring 4 is pivoted about the second pivot axis 9, the retaining means 412 are pivoted against the restoring force of the pivoting leg 41. This changes the position of the retaining means 412 until the clamping leg 32 of the clamping spring 3 is released. The locking and / or unlocking can be enabled by a locking aid, which is Fig. 1 is mounted so that it can move linearly.

[0081] A free space 13 is formed between the clamping spring 3 and the busbar 2, in which the electrical conductor 6 can be freely inserted in and against the sliding direction 7 in the locking state R of the clamping leg 32.

[0082] When the electrical conductor 6 inserted into the spring-loaded terminal 1 is moved in the sliding direction 7, the open end 63 of the electrical conductor 6 comes into contact with the pressure surface 42.

[0083] Upon further sliding in the sliding direction 7, the conductor 6 presses on the pressure surface 42. This pivots the pivoting leg 41 in the second pivoting direction 91. In the process, the clamping leg 32 is released from the holding means 412 and pivoted in the pivoting direction 81 into a clamping state K, as shown in Fig. 2a and Fig. 2b. The pressure surface 42 is arranged below the holding means 412 in the sliding direction 7, so that a free pivoting of the clamping leg 32 in and against the pivoting direction 81 is possible in a simple and safe manner.

[0084] The spring-loaded terminal 1 can also have a return means 5. The return means 5 is movable in and against the sliding direction 7. It is provided for pivoting the clamping leg 32 of the clamping spring 3 back against the pivoting direction 81. The clamping leg 32 can be pivoted back from the clamped state K to the latched state R by moving the return means 5 against the pivoting direction 7, so that the latching means 322 of the clamping leg 32 of the clamping spring 3 re-engages with the holding means 412 of the pivoting leg 41 of the retaining spring 4. An electrical conductor 6 previously clamped in the spring-loaded terminal 1 in the clamped state K can then be removed from the spring-loaded terminal 1 in the latched state R.

[0085] In the embodiment shown here, the return means 5 is in the locking position R (see Fig. 1 ) and in the clamping state K (see Fig. 2a and Fig. 2b) above the locking means 322 formed integrally on the clamping leg 32. Therefore, when the clamping leg 32 is in the clamping state K, the return means 5 acts directly on the clamping leg 32 when displaced in the sliding direction 7, so that the required displacement path for pivoting the clamping leg 32 back is small. Furthermore, the return means is formed essentially between the clamping spring and the conductor.

[0086] To actuate the return means 5, it can have an actuation groove that simplifies actuation with a tool such as a screwdriver. Furthermore, in the clamped state K, the return means 5 is clamped between the clamping leg 32 and the terminal housing 12, so that it cannot be released from the terminal housing 12.

[0087] The Fig. 1 shows the clamping spring 3 and the retaining spring 4 in the locking position R of the clamping leg 32 of the clamping spring 3. It can be seen that the clamping leg 32 is locked to the holding means 412 of the pivoting leg 41 of the retaining spring 4 via its locking means 322, which are formed approximately halfway along the longitudinal extent of the clamping leg 32. Clearly in Fig. 1 The free space 13 between the busbar 2 and the clamping leg 32 is also visible.

[0088] Fig. 1 explains the working principle of a clamping mechanism, which also applies to the variant of the Fig. 2 can be applied.

[0089] Fig. 2 shows a opposite Fig. 1 modified variant of a further arrangement 501 according to the invention comprising a clamping spring 503 and a retaining spring 504, which are designed as a one-piece electrically conductive component 501. As already in Fig. 1 The clamping spring 503 and the retaining spring 504 can also be used as an alternative to Fig. 2 be designed separately from one another and, for example, held in a housing and operatively connected via this.

[0090] The clamping spring 503 of the component 501 or of the arrangement according to the invention has a bend 530 analogous to the variant of the Fig. 1 which transitions into a support leg 531. The clamping spring 503 is pivotable in a pivoting direction 581 about a pivot axis 508 relative to the support leg 531 and can be locked to the retaining spring 504 via return means 505. The support leg 531 then transitions into a pivoting leg 541. The support leg 531 is arranged pivotable in the pivoting direction 571 about the pivot axis 509 relative to the pivoting leg 541. The pivoting leg 541 then transitions into a holding means 612 and, in a region of a bend 614, into a further leg 611.

[0091] This leg 611 has a terminally angled pressure surface 542 for stopping a conductor end analogous to Fig. 1 The leg 611 can be pivoted in the pivoting direction about a further pivot axis 591.

[0092] The retaining means 612 arranged on the leg 541 is hook-shaped, with the hook being pivotable about a pivot axis 506 in the pivot direction 561, preferably by a few degrees. This allows a locking engagement with a terminal stop surface 150 of the return means 505 of the clamping spring 503 and the said retaining means 612 of the retaining spring 504.

[0093] In extension of the area with the return means 505, the clamping spring 503 has a clamping leg 532, which extends beyond the locking area. This has a waist 523 and an adjoining abutment leg 521 for guiding past the holding means 612, which are preferably arranged on both sides of the clamping spring 503. The function of the above-described sub-areas of the arrangement 501 according to the invention becomes immediately apparent when considering the spring-loaded clamp 1 of the Fig. 1 .

[0094] Both the Fig. 1 as well as Fig. 2 The illustrated combination of clamping spring 3, 503 and retaining spring 4, 504 has corresponding stop surfaces 150 in the area of ​​the locking mechanism, which have been modified within the scope of the present invention.

[0095] The locking mechanism is essentially based on the support of the respective clamping spring 3, 503 on the retaining means 612 of the respective retaining spring. The clamping spring can be tensioned by the return means 5. The conductor 6 releases the clamping mechanism by pressing on the pressure surface 42, 542, whereby the release force depends, among other things, on the locking geometry, the force level of the construction, and the surface quality of the locking.

[0096] To modify and adjust the clamping forces for different application areas, it is important to modify the spring constant of the clamping spring, the retaining spring, and / or the assembly as a whole. It is well known that metals are elastically deformable to a certain extent before undergoing deformation under higher force. This latter effect corresponds to the ductility property of a metal.

[0097] The elasticity of a metal depends on several factors, including the nature of the metal lattice and the associated spacing of the metal atoms within the lattice, the size of the metal atoms, and other inclusions in the metal lattice. Targeted heating of the metal in one or more stages while maintaining its basic dimensional stability can, to a certain extent, lead to a reorientation of the metal lattice and, with it, a change in the elasticity of the metal and thus also of the metallic component. This particularly results in a reorientation of the metal due to lattice defects and the like. The same applies to alloys. This heating step can lead to surface oxidation tendencies and the formation of tarnish on the surface of the metallic component.Furthermore, undesirable amounts of retained austenite in the metallic structure decompose by diffusion at temperatures above 300°C to form ferrite and cementite. In summary, the metallic structure of a component changes during heating.

[0098] Through appropriate heat treatment of a spring coming out of the tool, the normal force of the respective spring component and thus the spring constant can be advantageously increased due to changes in the metal structure. At the same time, this change and possibly surface oxidation lead to a change in the surface quality of the metal. The coefficient of friction is increased, which is an undesirable change. The coefficient of friction µ is a crucial factor in triggering the mechanism for clamping the conductor and locking the clamping spring to the retaining spring. Several tests have observed that triggering the mechanism with the same force after starting became less reliable due to a greater variance in the coefficient of friction.

[0099] This disadvantage of a changed surface quality caused by tempering is reduced by a surface treatment, in particular by the application of a lubricant layer on the contact surfaces 152 between the clamping spring 3, 503 and the retaining spring 4, 504.

[0100] Preferably, the lubricant may be a PFPE-containing lubricant.

[0101] The lubricant may preferably also contain a solvent, preferably a base oil, to adjust the viscosity. The solvent content is advantageously less than 20% by weight.

[0102] Preferably, the proportion of PFPE, in particular hexafluoropropene, in the lubricant is more than 75 wt.%, preferably more than 85 wt.%.

[0103] The applied lubricant preferably has a density between 1.55-1.75 g / cm³ (at 20°C), which makes application particularly easy. The boiling point is preferably between 50-60°C. Therefore, subsequent application of the lubricant after tempering the metal components is recommended.

[0104] The lubricant is applied to the component only in sections, particularly in the contact area between the contact spring and the retaining spring. The coated application area can particularly preferably be less than 300% of the contact area, preferably less than 150% of the contact area.

[0105] The contact area 152 in the sense of the present application is the contact area in the locked state and the contact area in which the two springs slide over each other during the unlocking movement.

[0106] The contact surface 152 is thus related to Fig. 2 as the stop surface 150 and the adjacent surface 151 up to the edge of the holding means 612.

[0107] Fig. 3 shows the results of friction coefficients determined in laboratory tests. These were determined using an optical method within the framework of a microscopy or laser scanning process.

[0108] The curve labelled a) shows friction coefficient measurements of a tool-falling component with the design of the Fig. 2 . Conventional punching oil is present on the surface of the component.

[0109] The curve labelled b) shows the friction coefficient measurement of a component with punching oil which was annealed at 300°C for 1h.

[0110] The shortcut labelled c) shows the friction coefficient measurement of a component with punching oil which was annealed at 300°C for 1h and which was additionally coated with a PFPE-containing lubricant as described above.

[0111] The investigations show both the previously discussed increase in the coefficient of friction due to starting and the reduction in the coefficient of friction due to the application of lubricant.

[0112] The preferred layer thickness of the lubricant coating is at least 3 µm, particularly preferably 5-100 µm.

[0113] As an alternative to the application of the coating material to the arrangement according to the invention in a region-specific manner, the coating can be carried out by vapor-depositing the arrangement according to the invention or individual springs of the arrangement with the coating material, so that a full-surface coating is formed at least on one spring or over the entire arrangement. List of reference symbols

[0114] 1Spring-loaded terminal 11Insertion opening 12Terminal housing 13Free space 14Support contour 2Busbar 20Terminal housing 21Abutment leg 3Clamping spring 30Bend 31Supporting leg 311Retaining tab 312a, bConnecting leg 32Clamping leg 321Clamping edge 322Locking element 323Waist 324Elongated hole 4Retaining spring 41Pivoting leg 411Leg 412Retaining element 413Leg 414Bend 415Perforation 416Narrowing 418Recess 42Pressure surface 43Leaf spring 44Recess 45Stop element 5Reset means 51Actuating groove 6Electrical conductor 61Sheath 62Core 7Shift direction 8Swivel axis 81Swivel direction 9Swivel axis 91Swivel direction 100Terminal block 101Support rail 102Busbar 150 stop surface 151 adjacent surface 152 contact surface 501Arrangement 503Clamping spring 504Retaining spring 505Return device 506Pivot axis 509Pivot axis 521Abutment leg 523Sidecut 530Bend 531Support leg 532Clamping leg 541Pivoting leg 561Pivoting direction 571Pivoting direction 581Pivoting direction 591Pivoting axis 611Leg 612Holding means 614Bend 542Pressure surface 508Pivoting axis KKlamping state RRating state

Claims

1. An arrangement (501) comprising a clamping spring (3, 503), which acts as a pressure spring, for fixing an electrical conductor (6) in the spring-force clamp (1), and a retaining spring (4, 504) for locking the clamping spring (3, 503) in an open position, such that the conductor (6) can be introduced into a contact region in a shifting direction (7), wherein the clamping spring (3, 503) touches the retaining spring (4, 504) along a contact surface (152) in the locked state and during the movement from the locking state R into an unlocking state E, characterized in that at least the contact surface (152) has a lubricant-containing coating.

2. The arrangement according to claim 1, characterized in that the contact surface comprises both a stop face (150) between the retaining spring (4, 504) and the clamping spring (3, 503), and also the adjacent region (151) of the retaining spring (4, 504), over which the contact spring (3, 503) slides during the unlocking movement.

3. The arrangement according to any one of the preceding claims, characterized in that the lubricant-containing coating has a perfluoropolyether - PFPE.

4. The arrangement according to any one of the preceding claims, characterized in that a PFPE, preferably a hexafluoropropene, makes up more than 75 wt%, preferably more than 85 wt%, of the lubricant-containing coating.

5. The arrangement according to any one of the preceding claims, characterized in that a solvent, preferably a base oil, particularly preferably makes up less than 20 wt% of the lubricant-containing coating.

6. The arrangement according to any one of the preceding claims, characterized in that the applied lubricant has a density between 1.55-1.75 g / cm3 (at 20°C).

7. The arrangement according to any one of the preceding claims, characterized in that the arrangement (501) has, adjacent to the contact surface (150), an uncoated surface with a higher, preferably on average at least 50% higher coefficient of friction than the contact surface.

8. The arrangement according to any one of the preceding claims, characterized in that the arrangement (501) is formed as an integral component.

9. The arrangement according to any one of the preceding claims, characterized in that the arrangement (501) is colored through annealing coloring.

10. A spring-force clamp (1), formed as a direct-plugging clamp, for connecting a conductor, in particular a stranded conductor, which clamp has an arrangement according to any one of the preceding claims and which has at least the following: a. a busbar (2) for contacting an electrical conductor (6); b. the clamping spring (3, 503) of the arrangement according to any of the preceding claims, which acts as a pressure spring, for fixing the electrical conductor (6) in the spring-force clamp (1), c. the retaining spring (4, 504) of the arrangement according to any of the preceding claimsfor locking the clamping spring (3, 503) in an open position, such that the conductor (6) can be introduced in a shifting direction (7) into a contact region, d. wherein the clamping spring (3, 503) has a clamping leg (32, 532) with a clamping edge (321), which clamping leg (32, 532) can pivot in a pivoting direction (81, 581), and the retaining spring (4, 504) has a pivotable pivoting leg (41, 541), e. wherein the pivoting leg I (41, 541) has at least one retaining means (412, 612) and the clamping leg (32, 532) has a locking means (322, 522) which interacts with the retaining means (412, 612) of the pivoting leg (41, 541) in the locking state R of the clamping leg (32, 532), f. wherein the clamping leg (32, 532) can be adjusted from a locking state R, in which it is locked in the open position by the retaining means (412, 612) of the pivoting leg (41, 541), by shifting the electrical conductor (6) into a clamping state K in which the clamping leg (32, 532) is unlocked by the retaining means (412, 612) and pushes the electrical conductor (6) against the busbar (2) with the clamping edge (321) of the clamping leg (32, 532), characterized in that g. the locking means (322) of the clamping leg (32, 532) is formed spaced apart from the clamping edge (321) of the clamping leg (32, 532).

11. The spring-force clamp (1) according to claim 10, characterized in that it also comprises a resetting means (5, 505) for pivoting-back the clamping leg (32) with which the clamping leg (32, 532) can be pivoted back from the clamping state (K) into the locking state (R) by shifting the resetting means (5, 505) against the pivoting direction (81, 581).

12. The spring-force clamp (1) according to claim 10 or 11, characterized in that the resetting means (5, 505) or a surface for guiding the resetting means (5, 505) has a lubricant-containing coating.

13. A series terminal or plug connector with one or more spring-force clamps according to one or more of the preceding claims.

14. A method for producing an arrangement according to any one of the preceding claims, characterized by the following steps: a) forming the arrangement (501) or at least an element of the arrangement (501), in particular at least the retaining spring (4, 504) of the arrangement; b) thermally annealing the element, preferably at temperatures of more than 250°C; c) coating, at least in regions, the element with the lubricant-containing coating.

15. The method according to claim 14, characterized in that the coating is performed by vapor-phase coating of the arrangement according to the invention or an element of the arrangement according to the invention with the coating material.