Electrical contact part for connector and connector device equipped with electrical contact part

Abstract

The present invention describes an electrical contact part for a connector having a metallic flat contact plug, at least on the plug-in end face of which a plastic body is arranged, the cross section of the section of the plastic body extending from the plug-in end face of the flat contact plug having two wave-shaped peripheral contours which run symmetrically or asymmetrically relative to the central axis of the cross section and whose spacing along the plug-in direction varies continuously so that the contour progression has at least one local maximum outside the end region. The present invention also describes a connector arrangement comprising a connector having an electrical contact part and a counter contact part with at least one leaf spring.

Description

[Technical Field]

[0001] The present invention relates to an electrical contact element for a connector, which includes a metal flat contact plug and a plastic body disposed on at least the plug end surface, and further to a connector device including such an electrical contact element. [Background technology]

[0002] Any electrical circuit with high voltage must be contact-proof to prevent danger to the body and life. Therefore, in the automotive industry, especially in the engine compartment, connector connections have been implemented in a contact-proof manner for decades.

[0003] Connector manufacturers and designers have known and applied various methods of contact protection to their products for many years.

[0004] So-called passively contact protected connectors have a geometry adapted to preclude accidental contact.

[0005] An electrical contact element of this type with a contact guard made of plastic is known from US Pat. No. 5,649,999.

[0006] In particular, the section of the plastic body that contacts the plug-in end face of the flat contact plug influences the properties of the contact element during the plug-in process. Depending on the geometry of this section, relatively high plug-in forces or even an unfavorable progression of the plug-in forces may occur during the plug-in process. The wear of the plastic that occurs during the plug-in process also depends on the geometry of this section.

[0007] Additionally, the shape of the plastic body should make it as difficult as possible for fingers to get close to the flat contact plug in a given environment. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] German Patent Publication No. 102018211043 Summary of the Invention [Problem to be solved by the invention]

[0009] The object of the present invention is to realize an electrical contact element that is particularly advantageously configured with regard to the above requirements. [Means for solving the problem]

[0010] This problem is solved according to the invention in that the cross section of the section of the plastic body extending from the plug-in end face of the flat contact plug has two wavy peripheral contours that run symmetrically or asymmetrically relative to the central axis of the cross section, the spacing between these peripheral contours varying continuously along the plug-in direction, so that the contour progression has at least one local maximum outside the end region.

[0011] In the following, the distance between the peripheral contours measured perpendicular to the central axis of the cross-section will also be referred to as the "cross-sectional width".

[0012] Such a transition has been found to be particularly advantageous, since it results in a relatively low insertion force and abrasion of the plastic body when mating with a resilient mating contact. The low insertion force makes it easier to handle connectors equipped with such contact elements. Since abrasion of the plastic also deteriorates the electrical properties of the contact elements, it is desirable to reduce the abrasion of the plastic.

[0013] In this case, a double wave-shaped transition of the peripheral contour of the plastic body has proven to be particularly advantageous.

[0014] Advantageous embodiments and improvements of the invention emerge from the dependent claims and the following description of the invention based on the drawings. [Brief explanation of the drawings]

[0015] [Figure 1] Two schematic diagrams of electrical contact components and one detailed enlarged view [Figure 2] Schematic diagram of a connector device with a contact element and a mating contact element [Figure 3] Cross section of plug tip [Figure 4] Cross-sectional view of the plug tip with the contact surfaces marked [Figure 5] Cross-sectional view of two plug tips according to the prior art [Figure 6] Schematic diagram of a thin plate pair in one electrical contact component and two contact components according to the prior art DETAILED DESCRIPTION OF THE INVENTION

[0016] 1 shows an electrical contact element 10 according to the invention in a plan view of the contact surface 19 and in a cross section along line AA. In addition, an enlarged view of detail B of this cross section is shown.

[0017] The contact element 10 consists of a metal flat contact plug 11 with an injection molded plastic body 12 .

[0018] This integrally realized plastic body 12 can surround the flat contact plug 11 from multiple sides, where the side portions 14 of the plastic body 12 are in contact with the two elongated longitudinal sides of the flat contact plug 11, while the plug tip 13 connected to these side portions 14 is located on the insertion side end face of the flat contact plug 11.

[0019] The non-conductive plug tip 13 has the function of preventing a part of the human body from directly contacting the end face of the flat contact plug 11. The two side portions 14 perform the same function for the two elongated longitudinal sides of the flat contact plug 11. Therefore, the plastic body 12 forms a contact protection for the flat contact plug 11.

[0020] The accessibility of the front and rear contact surfaces 19 of the flat contact plug 11, which must be opened for contact with the mating contact element 20 (FIG. 2), is essentially limited by the housing part of the connector housing, not shown here, which surrounds the contact element 10 in a known manner.

[0021] The plug tip 13 formed by the plastic body 12 of the electrical contact element 10 according to the invention is characterized in that the cross section of each of its two peripheral surfaces forms at least one simple wave-like profile, and in the example shown here, each of them even forms a double wave-like profile.

[0022] The electrical contact element 10 is defined to constitute an electrical connector device together with a mating contact element 20, which is shown schematically in Fig. 2. To this end, the mating contact element 20 comprises a plurality of thin plates 26a, 26b, 26c, 26d, which can be arranged on the support element 21, shown here as a U-shaped support element 21, as opposed to each other, as thin plates 26a, 26c and 26b, 26d, or as thin plates 26a, 26b and 26c, 26d arranged in order in the insertion direction. In addition, further thin plates can be arranged parallel to the illustrated thin plates 26a, 26b, 26c, 26d in a plane parallel to the plane of the drawing, but these are not explicitly shown in Fig. 2.

[0023] Each of the lamellae 26a, 26b, 26c, 26d has a resilient section, here simply illustrated as a cylindrical spring, which will be referred to below as Thin The leaf springs 27a and 27b are respectively provided with one thin plate top portion 28a and 28b. Thin It is connected to the leaf springs 27a and 27b, and comes into contact with one of the contact surfaces 19 of the contact part 10 when the mating contact part 20 is completely connected to the contact part 10.

[0024] When the mating contact element 20 is connected to the contact element 10, the thin plate-shaped top portions 28a and 28b come into contact with the peripheral surface of the plug tip 13 and the contact surface 19 of the flat contact plug 11. When the contact element 10 is inserted, Thin The spring force of the leaf springs 27a and 27b generates an insertion force, the magnitude and transition of which are as follows: Thin This is determined by the implementation of the leaf springs 27a and 27b and the cross-sectional shape of the contact element 10.

[0025] While the flat contact plug 11 is generally simply realized with plane-parallel contact surfaces 19, the shape of the insulating plug tip 13 can vary fundamentally. However, since the purpose of the insulating plug tip 13, in addition to its contact protection function, was generally only to open the lamellae of the mating connector to such an extent that these lamellae could slide over the contact surfaces of the flat contact plug via the plug tip, simple cross-sectional shapes have generally been chosen up to now.

[0026] FIG. 5 shows two purely exemplary embodiments of insulating plug tips 13′, 13″ according to the prior art. In FIG. a), the front section of the plug tip 13′ forms a kind of dome, the cross section of which reaches the cross-sectional width of the flat contact plug 11 after a short distance in the plugging direction. With this plug tip 13′, particularly at the beginning of the plugging process, very large force loads must be applied in order to spread the contact lamellae. FIG. b) shows another embodiment, a wedge-shaped plug tip 13″, in which the plugging force continuously increases until it reaches the flat contact plug 11.

[0027] In the contact element 10 according to the invention, a new shape of the plug tip 13 has been discovered which optimizes the progression of the insertion force when mating the contact element 10 with the counter contact element 20. Figure 3 shows a perpendicular cross section of the electrical contact element 10 in the region of the plug tip 13. The peripheral contour 17a, 17b of the cross section 18 of this plug tip 13 is divided into a number of circled zones I, II, III, IV for the purposes of the following explanation.

[0028] The two peripheral contours 17a, 17b of the cross section of the illustrated plug tip 13 extend symmetrically to one another in this embodiment with respect to the central axis 22 of the cross section 18 of the plug tip 13 and each exhibit a wave-like progression, in this case in particular a double wave shape, which is characterized in that the cross-sectional width of the peripheral contours 17a, 17b changes continuously in the insertion direction and, in relation to this progression, has two maximum cross-sectional widths Max (zone II) that do not exist in the front or rear end sections of the peripheral contours 17a, 17b.

[0029] Specifically, the illustrated shape of the plug tip 13 has two peak zones II, each having a local maximum cross-sectional width Max, and a valley zone III therebetween, in which the cross-sectional width is locally minimized at a minimum cross-sectional width Min.

[0030] The beginning and end of the peripheral contours 17a, 17b also form local minimum cross-sectional widths Min in the chamfer zone I and in the recess zone IV of the plastic plug, where the transition of the peripheral contour begins with the molded chamfer 16.

[0031] The plastic surface of the plug tip 13 and the metal surface of the flat contact plug 11 meet at an angle of 90° to 179° in a recessed material transition area in recess zone IV, hereinafter referred to as "recess 15" for short. The metal area is configured to ensure an angled transition 29 at this material transition, which can be created by shaping a chamfer, a radius, an edge, or a polynomial. This recess 15 serves to prevent contact between the contact element 10 and the thin plate crowns 28a, 28b and 27a, 27b in the material transition area.

[0032] The wave shape of the plug tip 13 shown in FIG. 3 results in several contact zones a, b, c with qualitatively different effects in relation to the insertion process, which are plotted along the peripheral contour 17a of the plastic body 12 in the cross section of FIG. 4, due to the different gradients in the progression of this curve.

[0033] In this case, the symbol a represents a contact zone where the thin plates 26a, 26b, 26c, and 26d shown in Fig. 2 can slide without spreading when inserted into the mating contact element 12. In the contact zone b, the thin plates 26a, 26b, 26c, and 26d respectively spread, while in the contact zone c, the thin plates 26a, 26b, 26c, and 26d do not spread. Thin The leaf springs 27a and 27b are relaxed.

[0034] Over the entire contour of the plastic body 12, the sheet tops 28a, 28b contact the contact elements in turn in all three contact zones a, b, c. In this case, due to the expandability of the contact sheets 26a, 26b, 26c, 26d, a force load only occurs when one of the contact tops 28a, 28b slides over one of the contact zones, contact zone b. While the sheets 26a, 26b, 26c, 26d can slide over contact zone a without further expansion, when moving over contact zone c, each sheet 26a, 26b, 26c, 26d is actually relaxed.

[0035] In contrast, the prior art plug tips 13' and 13" shown in FIG. Thin There is no contact zone c to allow the leaf spring to relax in between.

[0036] The use of multiple contact surfaces helps to avoid damage to the sheets and distribute the force to be applied throughout the insertion stroke when mating the contact element 10 with the mating contact element 20. In this case, the load and relief areas of the sheets 26a, 26b, 26c, and 26d can be arranged alternately.

[0037] As shown in Figures 3 and 4, when the plug tip 13 has a multi-segment wave-shaped profile, the spacing between the waves is designed so that the sequentially arranged thin-plate domes 28a, 28b of the mating contact element 20 simultaneously contact areas of the plug tip 13 having significantly different cross-sectional widths.

[0038] This is shown diagrammatically in view c) of Fig. 6. When the load at the trailing contact point is at its maximum, the thin plate domes 28a, 28b in contact with the wavy peripheral contour 17a are connected to them. Thin It can be seen that the leaf springs 27a, 27b are now deflected by different amounts, which occurs several times in accordance with the progression of the peripheral contour 17a at the plug tip 13 in the wave-shaped contour.

[0039] These Thin By alternating load and relaxation zones of the leaf springs 27a, 27b, a limitation of the insertion force in the region of maximum zone II (FIG. 3) is achieved, thereby preventing the occurrence of extreme force peaks.

[0040] In comparison, views a) and b) of Figure 6 show diagrammatically the peripheral contours of the prior art plug tips 13' and 13" as shown in views a) and b) of Figure 5. At the maximum deflection of the trailing lamella 26b in this case, the leading lamella 26a in this case can only be at the same level, which creates a force peak.

[0041] The insertion force generated during the insertion process is Thin The setting operation of the leaf springs 27a and 27b, the frictional force due to the surface characteristics of the contact parts 10 and the thin plate top portions 28a and 28b, the shape of the peripheral contours 17a and 17b, Thin The leaf springs 27a and 27b are assembled from their respective contributions to the expansion movement, where the contributions vary over the course of the insertion region.

[0042] This setting action is ThinThis represents a mechanical operation that must be performed to retain the plastic deformation of the leaf springs 27a and 27b. Therefore, this setting operation must be performed only once when the mating contact device 12 is used for the first time. This one-time mechanical setting operation is Thin The end occurs when the leaf springs 27 a , 27 b reach their maximum deflection, and is therefore determined by the maximum cross section of the contact piece 10 .

[0043] The plug tip 13 with its wavy peripheral contour divides the setting action into several regions in the force vs. stroke curve. Thin The leaf springs 27a and 27b can be continuously deflected.

[0044] The engraving of the wavy peripheral contours 17a, 17b of the plastic body 12 makes it possible to prevent simultaneous complete deflection of all the sheet domes 28a, 28b, especially when the sheet geometry is such that the sheet domes 28a, 28b are staggered. Thin This reduces the maximum force when expanding the leaf springs 27a, 27b, especially when setting them.

[0045] The sheet metal cups 28a, 28b do not come into contact with the recess 15 between the plastic and metal areas (zone IV in FIGS. 2 and 3). This firstly reduces the wear that occurs, since they do not pass over the edge of the material transition. Secondly, the recess prevents additional force peaks from occurring in the force-travel curve at the transition from the plastic body 12 to the flat contact plug 11. Thirdly, loose particles can float in the area of ​​the recess 15 and remain in the area where the sheet metal cups 28a, 28b do not come into contact. [Explanation of symbols]

[0046] 10 Contact parts 11 Flat contact plug 12 Plastic Body 13, 13', 13" plug tip 14 Side part 15. Depression 16 Chamfered part 17a, 17b Peripheral contour 18 Cross Section 19 Contact surface 20 Mating contact part 21 Support member 22 Center axis 26a,26b,26c,26d thin plate 27a, 27b Thin Leaf spring 28a, 28b Thin plate top 29 Angled Transitions a,b,c Contact zone (contact surface) a. Contact zone (gliding without expansion movement) b Contact zone (during the insertion process) Thin (Enlarged view of leaf spring) c Contact zone (relaxation of the lamella during the insertion process) Zones I, II, III, IV I Chamfer zone of plastic plug II Mountain Zone III Valley Zone IV Depression Zone

Claims

1. An electrical contact part (10) for a connector, comprising a metal flat contact plug (11) and a plastic body (12) disposed on at least the end face of the plug on the insertion side, The electrical contact component is characterized in that a cross section (18) of a section of a plastic body (12) extending from the plug-in end face of the flat contact plug (11) has two wave-shaped peripheral contours (17a, 17b) extending symmetrically or asymmetrically with respect to a central axis (22) of the cross section (18), and the distance between these contours varies continuously along the plug-in direction, so that the progression of the contours has at least one local maximum value (Max) outside the end region.

2. The electrical contact device according to claim 1, The electrical contact component is characterized in that the transition of the peripheral contour (17a, 17b) of the plastic body (12) to the contact surface (19) of the metallic flat contact plug (11) forms a concave recess (15).

3. The electrical contact device according to claim 1, The electrical contact component is characterized in that the transition from the flat contact plug (11) to the plastic body (12) is configured as an angled transition (29) in the form of a chamfer, a radius, an edge or a polynomial.

4. A connector assembly comprising a connector with at least one electrical contact element having all the features of claim 1, A connector device comprising a mating contact part (20) having a plurality of thin plates (26a, 26b, 26c, 26d) that contacts a flat contact plug (11).

5. 5. The connector device according to claim 4, A connector arrangement, characterized in that the mating contact element (20) comprises at least two laminae (26a, 26b; 26c, 26d) arranged one after the other in the plug-in direction.

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