EP2932565B1 - Contact element and method for producing same - Google Patents

Description

The invention relates to a contact element having contact points for the electrically conductive connection of contact areas of spaced elements, e.g. Printed circuit boards. The invention further relates to a method for producing such a contact element and to a contact device comprising a plurality of such contact elements.

Generic contact elements are used for example for the formation of so-called board-to-board (B2B) connector, with which two spaced-apart printed circuit boards are electrically connected.

The contact elements are intended to ensure a loss-free transmission of the high-frequency signals in a defined tolerance range with respect to the parallelism, the distance and a lateral offset of the two circuit boards or its contact areas. Other requirements are cost-effective production and easy installation. In addition, the axial and radial dimensions of the contact elements should be as small as possible, as a result of the further progressing miniaturization of the printed circuit boards or the printed conductors applied thereto, the number of side by side in a limited space to be arranged contact elements steadily increases.

It is known to produce a connection between two printed circuit boards by means of two coaxial connectors fixedly connected to the printed circuit boards and an adapter connecting the two coaxial connectors, the so-called "Bullet". This adapter allows axial and radial tolerance compensation, as well as the compensation of parallelism tolerances. Typical coaxial connectors used for this purpose are SMP, mini-SMP or FMC.

Alternatively, electrical connections between two printed circuit boards are also realized via spring contact pins in single-conductor and / or multiple-conductor construction. Such spring contact pins include a sleeve and a partially guided within the sleeve head and a coil spring which is supported between the head and the sleeve. Required for the coil spring properties with respect to spring force and block length require relatively large spring lengths, which have a correspondingly detrimental effect on the axial height of the spring contact pins.

From the US 6,776,668 B1 Furthermore, a coaxial contact element is known, via which high-frequency signals are to be transmitted between two printed circuit boards. In this case, an inner conductor, which is designed in the form of a spring contact pin, serves as a signal conductor, while a peripheral conductor surrounding the inner conductor has the function of a return conductor and a shield for the inner conductor. The outer conductor comprises a sleeve-shaped base body, which is slotted multiple times in the longitudinal direction. The non-slotted end of the base body forms the front side of a contact point for contacting a contact region of the circuit boards. On the main body, a sleeve of the outer conductor is displaceably guided, which forms at one end of the end face a contact point for contacting a contact region of the other printed circuit board. Between the base body and the sleeve, a prestressed spring is supported. When connecting the two circuit boards both the head of the inner conductor and the sleeve of the outer conductor are among others Bias of the respective springs displaced, whereby despite possible tolerances in the distance of the contact areas of the circuit boards from each other a secure contact pressure can be provided. By the slit of the body this also has a certain flexibility in the lateral direction, which is to be achieved that even relatively large non-parallelism between the two contact areas can be compensated.
Basically, the known contact elements on relatively large dimensions, which are also due to their construction and the resulting function, not arbitrarily reduced. For example, the reduction of the diameter of male-female connections, as used, inter alia, in said SMP connectors, only up to a certain limit possible because otherwise in the materials commonly used strength problems of plug and socket, especially in Mating the connector, would result.

The EP0184608 A2 discloses a contact element according to the preamble of claim 1.

Based on this prior art, the present invention seeks to provide a generic contact element, which is characterized by extremely small dimensions and thereby allows the formation of a contact device in which the largest possible number of these contact elements are housed in a given space.

This object is achieved by a contact element according to independent claim 1. A method for producing such a contact element is the subject of independent claim 10. A contact device comprising a plurality of such contact elements is the subject of independent claim 13. Advantageous embodiments of the contact element according to the invention are the subject of the dependent claims and will become apparent from the following description of the invention ,

The basic idea of the invention is a miniaturization of a generic contact element by the use of alternative, for the production of such contact elements previously unused manufacturing process to achieve. This basic idea was based on the finding that pure miniaturization of the known contact elements, inter alia due to the already mentioned strength problems, can not lead to success, but rather a change in the functional configuration would have to be associated with the miniaturization. Another finding was then that such a functional redesign in conjunction with the desired dimensions probably can only be achieved by the contact element is formed in one piece. The sought alternative manufacturing processes thus had to make it possible to produce highly complex geometries in extremely small dimensions at a reasonable cost, whereby a material would have to be processable which enables the integration of the functionalities required for generic contact elements.

This principle of the invention is implemented in a (three-dimensional) contact element with contact points for electrically conductive and space bridging connection of contact areas spaced elements, in particular printed circuit boards, which is formed entirely of one or more deposited materials, of which at least one is electrically conductive.

The "deposition" of (precipitation of) materials allows the design of extremely small yet highly complex geometries. The further intended, preferred use of a metal for deposition and thus for the formation of the contact elements allows the integration of the essential, required for generic contact elements functionalities, namely the electrical conductivity and the generation of a contact pressure due to the electrical conductivity properties and the good elasticity of many metals the good contact of the contact points with the contact areas of the elements to be connected can be ensured in the miniaturized contact element. Instead of a training of the contact element completely from one or For example, plastics can also be used for a plurality of deposited metals. For this purpose, they should preferably have the required elasticity and / or be electrically conductive. Alternatively, however, can also be formed by the additional deposition of one or more metal layers, a partially made of plastic contact element electrically conductive, in particular in a final deposition step.

For the deposition of the material or materials, any suitable, known from the prior art method can be provided. Particularly preferred methods for depositing and thus producing a contact element according to the invention are the so-called LiGA methods. The term "ligand" is a compound from which the essential steps of this method descriptive terms "lithography", "G alvanik" and "A bformung".

The LiGA process (many variations are possible) is characterized by the ability to produce microstructures of extremely small dimensions of e.g. 0.2 μm, structural heights up to 3 mm, and aspect ratios of e.g. 50 (for detail structures as high as 500) of e.g. the materials plastic, metal or ceramic allows.

For producing a contact element by means of a LiGA process, provision can be made in particular to apply to a planar substrate, for example a silicon wafer or a polished disk of, for example, beryllium, copper, titanium, a photo- or X-ray-sensitive resist layer of, in particular, polymethylmethacrylate (PMMA) Negative, but preferably can be provided as a positive resist. If the substrate is not itself electrically conductive, this can be provided with a metallic seed layer. This can be done in particular by "sputter deposition" or vapor deposition. Thereafter, the resist layer is exposed and developed, whereby a negative mold of the contact element to be produced is formed. In a deposition process is a material, preferably metal (or more materials or metals layer by layer) deposited on the substrate in the negative mold. Preferably, it can be provided to deposit the material (s) galvanically, although other deposition methods, such as PVD or CVD, are also possible. After removing the remaining resist, the substrate, the seed layer and the deposited material remain first. This may already be the contact element, if an electrically conductive material, in particular a metal, has been deposited in at least one layer. The contact element can then be detached from the substrate by, for example, etching the seed layer.

Alternatively it can also be provided to provide the finally deposited structure as a mold of an impression tool. For this purpose, a further deposition with, in particular, a "overgrowth" (of a part) of the remaining resist layer and a subsequent removal of substrate and seed layer can be provided. The contact element to be produced can then be produced by, for example, injection molding or hot stamping. This is particularly suitable for the production of the contact element or a main body of the contact element made of plastic. If the plastic is not electrically conductive, can then be provided to deposit an electrically conductive material, in particular a metal in the form of a coating

If deposited structures with a greater thickness are required, it may be provided to use the described method for forming a mask, which in turn is then used for the targeted exposure of a thicker resist layer. In these cases, gold is often deposited in the mask, which is characterized by a strong absorption of X-radiation. In addition, it may be provided to carry out the gold deposition on a titanium membrane (thus you were in the mask production between the substrate and the resist layer), which is characterized by an extremely low absorption of the X-radiation.

In particular, X-rays or ultraviolet (UV) light can be used to expose the resist layer, whereby the use of X-radiation tends to promise higher precision and the use of UV light reduces costs.

In order to achieve the most cost-effective possible production of a contact element according to the invention by means of a method according to the invention, it can preferably be provided that a plurality of directly or indirectly contiguous contact elements are generated during the implementation of a LiGA process, which are then separated.

In a preferred embodiment, the contact element according to the invention (at least) have a spring portion which is elastically deformed when contacting the contact areas. This spring portion extending from the one or more portions of the contact element by a lower spring stiffness with respect to the connection direction, i. the connecting line of the contact points, is distinguished, can serve in particular for the compensation of shape and position tolerances of the contact element and the contact areas to be connected and to ensure a defined contact pressure.

Particularly preferably, it may be provided that the spring section is arranged between two rigid support sections, which do not become relevant or not functionally deformed in the case of the forces regularly occurring during the contacting of the contact areas. The support sections can in particular ensure a good (kink) stability of the contact element.

The spring portion may preferably be meander-shaped. Such a spring section can be easily produced by means of the method according to the invention.

Alternatively, the spring section can have a plurality of coaxially arranged, have arcuate spring tabs. Even such spring tabs can be produced according to the invention well. Particularly preferably, it can then be provided that adjacent spring tabs contact each other during the contacting of the two contact areas as a result of the deformation of the spring section. Thereby, the spring portion, if provided that this is part of the signal or current path, have a relatively low electrical resistance.

In a further preferred embodiment of the contact element according to the invention, a latching connection can be provided, which holds the contact element in a spring portion partially deformed position. As a result, the spring section can already be prestressed in an unloaded neutral position of the contact element, as a result of which it can already produce a relatively large contact pressure even with only slight further deformation during the contacting of the contact areas.

Further preferably, it can then be provided that in a further deformation of the spring section, the sections forming the latching connection slide off one another. The latching connection forming portions (this may preferably be the support portions) may thus guide the relative movement of the sections connected by the spring portion and thereby positively influence the stability of the contact element.

In order to produce such a contact element, provision may be made for the contact element or elements to be deformed only after production and, if appropriate, after separation for latching the latching connection (s).

In a further preferred embodiment of the contact element according to the invention can be provided that between the contact points a signal or current path is formed, which bypasses the or the spring sections. This embodiment is based on the idea that the spring section regularly by relatively small cross sections of the deposited, electrically conductive material and thus by a characterized by relatively high electrical resistance. A signal or current path should therefore extend without the inclusion of the spring section over the remaining sections of the contact element, which preferably have larger cross-sectional areas.

A contact device according to the invention comprises a (preferably at least partially electrically insulating) receptacle having a plurality of through holes arranged side by side, and a plurality of contact elements according to the invention, wherein the contact elements are arranged in the through holes of the receptacle, which project beyond the receptacle with the contact points having sections. As a result, an easily manageable unit with a multiplicity of contact elements according to the invention can be produced. In addition, the contact elements can be supported by the receptacle in the through holes in the lateral direction.

Fig.1:

eine erste Ausführungsform eines erfindungsgemäßen Kontaktelements in einer perspektivischen Ansicht;

Fig. 2:

das Kontaktelement gemäß Fig. 1 in einer Seitenansicht;

Fig. 3:

einer Vergrößerung des Ausschnitts III in Fig. 2;

Fig. 4:

einer Vergrößerung des Ausschnitts IV in Fig. 2;

Fig. 5:

einer Vergrößerung des Ausschnitts V in Fig. 2;

Fig. 6:

einer Vergrößerung des Ausschnitts VI in Fig. 2;

Fig. 7:

einen Ausschnitt einer erfindungsgemäßen Kontaktvorrichtung mit Kontaktelementen gemäß den Fig. 1 bis 6 in einem Querschnitt;

Fig. 8:

eine Anordnung der Kontaktelemente in der Kontaktvorrichtung gemäß Fig. 7;

Fig.9:

eine zweite Ausführungsform eines erfindungsgemäßen Kontaktelements in einer perspektivischen Ansicht;

Fig. 10:

einen Ausschnitt einer erfindungsgemäßen Kontaktvorrichtung mit Kontaktelementen gemäß den Fig. 10 bis 12 in einem Querschnitt;

Fig. 11:

eine Anordnung der Kontaktelemente in der Kontaktvorrichtung gemäß Fig. 12;

Fig. 12:

ein System aus zwei Leiterplatten und einer Kontaktvorrichtung gemäß Fig. 11 in einer perspektivischen Explosionsansicht;

Fig. 13:

das System gemäß Fig. 12 in einer Seitenansicht;

Fig. 14:

eine Vergrößerung des Ausschnitts XIV in Fig. 12;

Fig.15:

eine dritte Ausführungsform eines erfindungsgemäßen Kontaktelements in einer Seitenansicht;

Fig. 16:

eine Vielzahl zusammenhängend hergestellter Kontaktelemente gemäß den Fig. 15;

Fig.17:

eine vierte Ausführungsform eines erfindungsgemäßen Kontaktelements in einer ersten Stellung;

Fig. 18:

das Kontaktelement gemäß Fig. 17 in einer zweiten Stellung;

Fig. 19:

das Kontaktelement gemäß Fig. 17 in einer dritten Stellung;

Fig. 20:

eine erfindungsgemäße Kontaktvorrichtung mit Kontaktelementen gemäß den Fig. 17 bis 19 in einer perspektivischen Ansicht;

Fig. 21:

einen Diagonalschnitt durch die Kontaktvorrichtung gemäß Fig. 20;

Fig. 22:

eine fünfte Ausführungsform eines erfindungsgemäßen Kontaktelements in einer ersten Stellung;

Fig. 23:

einen ersten Schritt eines erfindungsgemäßen Verfahrens;

Fig. 24:

einen zweiten Schritt eines erfindungsgemäßen Verfahrens;

Fig. 25:

einen dritten Schritt eines erfindungsgemäßen Verfahrens; und

Fig. 26:

einen vierten Schritt eines erfindungsgemäßen Verfahrens.

The invention will be explained in more detail with reference to embodiments shown in the drawings. In the drawings shows:

Fig.1:

a first embodiment of a contact element according to the invention in a perspective view;

Fig. 2:

the contact element according to Fig. 1 in a side view;

3:

an enlargement of section III in Fig. 2 ;

4:

an enlargement of the section IV in Fig. 2 ;

Fig. 5:

an enlargement of the section V in Fig. 2 ;

Fig. 6:

an enlargement of the section VI in Fig. 2 ;

Fig. 7:

a section of a contact device according to the invention with Contact elements according to the Fig. 1 to 6 in a cross section;

Fig. 8:

an arrangement of the contact elements in the contact device according to Fig. 7 ;

Figure 9:

a second embodiment of a contact element according to the invention in a perspective view;

Fig. 10:

a detail of a contact device according to the invention with contact elements according to the 10 to 12 in a cross section;

Fig. 11:

an arrangement of the contact elements in the contact device according to Fig. 12 ;

Fig. 12:

a system of two printed circuit boards and a contact device according to Fig. 11 in an exploded perspective view;

Fig. 13:

the system according to Fig. 12 in a side view;

Fig. 14:

an enlargement of the section XIV in Fig. 12 ;

Figure 15:

a third embodiment of a contact element according to the invention in a side view;

Fig. 16:

a plurality of contiguous manufactured contact elements according to the Fig. 15 ;

Figure 17:

a fourth embodiment of a contact element according to the invention in a first position;

Fig. 18:

the contact element according to Fig. 17 in a second position;

Fig. 19:

the contact element according to Fig. 17 in a third position;

Fig. 20:

a contact device according to the invention with contact elements according to the 17 to 19 in a perspective view;

Fig. 21:

a diagonal section through the contact device according to Fig. 20 ;

Fig. 22:

a fifth embodiment of a contact element according to the invention in a first position;

Fig. 23:

a first step of a method according to the invention;

Fig. 24:

a second step of a method according to the invention;

Fig. 25:

a third step of a method according to the invention; and

Fig. 26:

a fourth step of a method according to the invention.

In the Fig. 1 to 6 a first embodiment of a contact element 7 according to the invention is shown. The one-piece, formed from an electrically conductive metal contact element 7 has been prepared according to the invention by means of a LiGA process whose basic process steps in the FIGS. 23 to 26 are shown by way of example.

In the Fig. 23 It is shown how a resist layer 2 of PMMA arranged on a substrate 1 is irradiated through a mask with synchrotron radiation 5. The mask has a membrane 3 (for example of titanium) which is largely permeable to the synchrotron radiation and on which an absorber structure 4 made of a material which absorbs the synchrotron radiation (eg gold) is applied. This results in the irradiated portions of the resist layer 2 to a conversion of the long-chain molecules of PMMA into short-chain molecules, which selectively dissolve in a wet-chemical development step against the unirradiated sections and thus can be removed (see. Fig. 24 ).

The resulting on the substrate 1 free spaces are then filled by electrodeposition of a metal 6 (see. Fig. 25 ). After dissolving the remaining resist layer 2 (see. Fig. 26 ) and detachment from the substrate 1, the desired structure of the deposited metal 6 is obtained.

In the FIGS. 25 and 26 this is merely exemplified as any metal structure. According to the invention, the metal structure has the shape of one or more contact elements 7, which are connected to defined connection points, as shown in FIG Fig. 12 is shown by way of example for an embodiment of a contact element 7 according to the invention. Connected contact elements 7 can be separated by a separation at joints 8, for example by means of a laser.

That in the Fig. 1 to 6 illustrated contact element 7 comprises two support sections 8, each forming a contact point 9, which are formed for contacting a contact region of an element (not shown). By means of the contact element 7, the contact areas of the elements are thus to be connected in an electrically conductive manner in order in particular to transmit high-frequency signals. The contact point 9 of the one, in the Fig. 1 and 2 Supporting section 8 shown above comprises a contact surface arranged obliquely with respect to a longitudinal axis 10 of the contact element 7 and a tip extending from this contact surface at the edge. The tip serves to penetrate a possibly existing oxide layer on the contact region to be contacted and if necessary to remove it as a result of a relative movement to the contact region. This should ensure a good contact with the lying below the oxide layer metal of the contact area.

The two relatively rigid support sections 8 are connected to one another via a meandering (main) spring section 11. A displacement of the support elements 8 relative to each other with respect to the longitudinal axis 10 of the contact element leads to a deformation and bias of the (main) spring portion eleventh

The in the Fig. 1 and 2 Support section 8 shown below has at its lower end two more, parallel to each other and also meandering extending spring portions 12. These are connected at their one end in each case with the lower end of the support section 8 and with the other end in each case with the transverse part of a T-shaped piston 13. The spring sections 12 facing away, slightly curved outer surface of the cross member forms the one contact point 9 of the contact element 7.

The two support sections 8 further each form a latching lug 14, which together form a latching connection, which limits a relative displacement of the support sections due to the then biased to train (main) spring section 11 after snapping. In the Fig. 1 to 3 the contact element 7 is still shown with released latching connection, as it is produced during the production by means of the method according to the invention. By a pressure load on the two ends of the contact element 7, the locking connection under temporary elastic deflection of the locking lugs 14 having portions of the support portions 8 are engaged. In this case, the (main) spring portion 11 is biased to train.

At the same time a functionally corresponding locking connection between the lower support portion 8 and the piston 13 is formed, wherein the spring portions 12 are biased to pressure (see. Fig. 5 ).

The lower support portion 8 further includes a clamping portion 15 which extends slightly inclined relative to the longitudinal axis 10 of the contact element 7. As a result of this inclined course, the free end of the clamping portion 15 is pressed by the upper support portion 8 in its relative movement to the lower support portion 8 to the outside and thus elastically deflected. This serves to fix the contact element 7 in a passage opening of a support plate 16 frictionally, as shown in the Fig. 7 is shown. In this case, the non-positive fixation is intended in particular against a pressing out of the contact element 7 down Secure from the passage opening, wherein due to the configuration of the clamping portion 15 of the laterally directed pressure is proportional to the application of force from above to the contact element 7. This allows a secure non-positive fixation even at high forces (from above, with the corresponding counter-forces from below) can be achieved while the contact element 7 can be removed after the discharge of the upper support section 8 without significant effort from the through hole.

The fixation of the contact element in the passage opening at a load upward is achieved form-fitting by striking a shoulder 16 of the lower support section 8 at a complementary paragraph 17 in the passage opening.

The inventive method allows the production of extremely small contact elements 7. For example, thus a contact element 7 can be made, with respect to the in the Fig. 2 to 7 Dimensions shown have the following dimensions: a: 5.61 mm; b: 0.424 mm; c: 0.008 mm; d: 0.012 mm; e: 0.012 mm; f: 0.018 mm; g: 0.013 mm; h: 0.028 mm; i: 0.042 mm; j: 0.015 mm; k: 0.01 mm; l: 0.01 mm; m: 0.018 mm; n: 0.01 mm; o: 0.018 mm; p: 0.12 mm (diameter); q: 5.02; r: 5.46 mm; s: 5.11 mm; t: 0.42 mm. The (constant) thickness of this contact element 7 is 0.15 mm.

In the Fig. 7 a section of a contact device according to the invention is shown. This comprises a receptacle 18 with a plurality of through holes arranged in parallel, in each of which a contact element is arranged and fixed in the manner described. In the Fig. 7 is exemplified in only two of the three through holes, a contact element 7 is arranged. In addition, a contact element 7 is shown in its held by the latching connection neutral position and the other with almost maximum stroke. This is intended to illustrate the tolerance-compensating function of the (main) spring section 11 of the contact elements 7.

The concrete arrangement of the passage openings and thus the contact elements 7 in the receptacle 18 takes place in dependence on the function to be achieved with the contact device. In the Fig. 8 a first exemplary arrangement is shown in which a total of nine contact elements 7 in a square arrangement with diagonal orientation of the individual contact elements 7 disclosed. It can be provided via the central contact element 7 (radio frequency) to transmit signals, while the others are connected to ground and serve as a counter-pole. This results in a shielded arrangement of the signal contact element 7, which corresponds functionally to the inner conductor of a conventional Koaxialkontaktelements and is characterized at the same time by extremely small dimensions. The in the Fig. 8 The arrangement shown may have the following dimensions according to the dimensions there: a: 0.4 mm; b: 0.566; c: 0.15 mm; d: 0.24 mm.

The signal and current path between the two contact points 9 of the contact element 7 is primarily formed by the two support sections 8 and connected to the lower support section 8 piston 13, which faces the spring sections 11, 12 by a larger cross-sectional area and thus a lower electrical resistance distinguished. By the contact of the two support portions 8 and the lower support portion 8 with the piston 13 in the region of the locking connections and the clamping portion 15 of the signal or current path, bypassing the spring sections 11, 12 is formed.

The FIGS. 9 and 10 show a second embodiment of a contact element according to the invention 7. This comprises a relatively stiff support section 8 and two spring sections 11. The spring sections 11 each comprise three arcuate spring tabs 19, of which the respective outer is angled at its free end. In the region of the bend, the outer spring tabs 19 form on the outside each a contact point 9. The free end of the bent portion also forms in each case a detent 14, which in conjunction with the locking lug 14th one of two locking arms 20 of the support section 8 forms a latching connection.

The support portion 8 forms on one side of a contact surface 21, via which the contact element 7 is supported in a through hole of a receptacle 18. On the opposite side of the support portion 8 also forms a spring tab 22 which prints in the passage opening under bias against the adjacent opening wall and thereby increases the friction between the contact surface 21 and the opening wall. The contact element 7 is thereby frictionally held in the passage opening (see. Fig. 10 ).

The Fig. 9 shows the contact element in the mold, as it is produced in a method according to the invention. In this form, neither the locking connections are engaged, nor contact the three spring tabs 19 of the two spring sections 11 each other. Such contact and the engagement of the latching connections is effected by the exertion of compressive forces on the two contact points 9 and a deformation of the spring sections 11 effected thereby.

That in the FIGS. 9 and 10 Contact element 7 shown, for example, according to the dimensions there have the following dimensions: a: 1.3 mm; b: 1.0 mm; c: 0.39 mm; d: 0.72 mm. The (constant) thickness of the contact element 7 can be 0.15 mm.

The Fig. 11 shows a possible arrangement a plurality of in the FIGS. 9 and 10 Shown is a parallel arrangement in a total of five rows. In this case, an arrangement for a symmetrical signal transmission (100 Ω impedance) is selected in the top row. Thus, the contact elements 7 are provided for the signal transmission in pairs, with each connected to ground on each side of each pair of contact element 7. In the four lower rows, however, a single-ended signal transmission (50 Ω impedance) is provided, so that the signal contact elements 7 and the Ground contact element 7 are arranged alternately. The electrical insulation of all signal contact elements 7 is achieved by means of dielectric receiving elements 23, each receiving a signal contact element 7 and are themselves integrated into a receptacle 18.

The in the Fig. 11 The arrangement shown may have the following dimensions according to the dimensions there: a: 1.8 mm; b: 0.8 mm; c: 0.15 mm; d: 0.2 mm; e: 1.0 mm; f: 0.5 mm; g: 0.95 mm; h: 1.6 mm.

Of course, there is also the possibility of that in the FIGS. 9 and 10 illustrated contact element 7 in the in the Fig. 8 to provide the arrangement shown. Possible dimensions can then be: a: 0.8 mm; b: 1.13 mm; c: 0.43 mm.

The Fig. 12 to 14 Such an arrangement of the contact elements 7 in a board-to-board contact device 24 according to the invention for the connection of two printed circuit boards 25. The connection is fixed via two pressure plates 26 and 27 screwed.

In the Fig. 15 a third embodiment of a contact element 7 according to the invention is shown. This corresponds largely to that of FIGS. 9 and 10 However, wherein the non-positive fixation in a through hole serving spring tab 22 merges into a terminal block 28. As a result, an improved fixation of the contact element 7 in a passage opening of a receptacle 18 can be realized.

The Fig. 16 again illustrates the simultaneous production of a plurality of inventive contact elements 7 in a process passage. There, the metallic structure produced in the method according to the invention is shown, which comprises the contact elements 7, and a frame 29 holding the contact elements 7 via a respective connection point 8. Shown are a total of 95 contact elements 7, which were generated on a surface with the dimensions 16.1 mm x 9.4 mm.

The 17 to 19 show a fourth embodiment of a contact element according to the invention 7. This corresponds largely (also in terms of dimensions) of the embodiment according to the Fig. 1 to 6 , An essential difference is the design of the lower spring portion 12, which is formed here in the form of a curved, double spring tab. The 17 to 19 show this contact element 7 in different positions. In the Fig. 17 the contact element 7 is shown as it is directly after the preparation by means of a method according to the invention. In the Fig. 18 the locking connection was already engaged and thereby biased the (main) spring section 11. This represents a neutral position of the prepared for use contact element 7. In this neutral position, the contact elements 7 are installed in the through hole of a receptacle 18 of a contact device according to the invention, as shown in the FIGS. 20 and 21 is shown. In the Fig. 19 the pushed-together contact element 9 is shown with use of the total of the (main) spring section 11 provided travel.

Particularly noteworthy are the extremely low spring forces which can be achieved in the deformation of the / the spring portion / -e 11, 12 inventive contact elements 7. For example, the spring force of the biased in the neutral position (main) spring portion 11 of the in Fig. 17 to 21 shown contact element 7 only about 0.04 N and in the fully collapsed position about 0.1 N. Relevant are the low spring forces when a plurality of inventive contact elements 7 are to be combined in a close arrangement in a contact device according to the invention. Then also the sum of these spring forces and thus the load on the elements to be electrically connected (circuit boards) and possibly applied to the insertion forces for connecting the elements remains relatively low.

The Fig. 22 shows a fifth embodiment of a contact element 7 according to the invention special feature in this Contact element 7 is that the two support sections 8 do not touch directly, but are exclusively connected to each other via the (main) spring section 11. In this contact element 7 thus represents the (main) spring portion 11 is a part of the signal and current path. The fixation of the contact element 7 in a through hole of a receptacle 18 is effected by two spring-mounted clamping portions 31.

Claims (11)

1. Contact element (7) having contact points (9) for the electrically conductive connection of contact regions of mutually spaced elements, wherein said contact element is completely formed of one or more deposited materials, of which at least one is electrically conductive, characterised by a spring section (11, 12) which is elastically deformed when contact is made with the two contact regions, and a snap-lock connection which holds the contact element (7) in a position in which the spring section (11, 12) is partially deformed.
2. Contact element (7) according to claim 1, characterised in that the spring section (11, 12) is arranged between two rigid supporting sections (8).
3. Contact element (7) according to one of the preceding claims, characterised in that the spring section (11, 12) is meander-formed in design.
4. Contact element (7) according to one of the preceding claims, characterised in that the spring section (11, 12) has several coaxially arranged curved spring tabs (19), wherein adjacent spring tabs (19) make contact when contact is made with the two contact regions.
5. Contact element (7) according to one of the preceding claims, characterised in that, on a further deformation of the spring section (11, 12), the sections forming the snap-lock connection slide against each other.
6. Contact element (7) according to claims 2, characterised in that the snap-lock connection is formed by the supporting sections (8).
7. Contact element (7) according to one of the preceding claims, characterised through a signal or current path between the contact points (9) which bypasses the spring section (11, 12).
8. Method for the manufacture of a contact element (7) according to one of the preceding claims using a LiGA method.
9. Method according to claim 8, characterised in that, in a LiGA method, a plurality of connected contact elements (7) is created which contact elements are subsequently separated.
10. Method according to claim 8 or 9 characterised in that the contact element(s) (7) is/are deformed following manufacture and possibly following separation in order to engage the snap-lock connection(s).
11. Contact device having a mounting (18) which possesses a plurality of through-openings, as well as having several contact elements (7) according to one of the claims 1 to 7, wherein the contact elements (7) are arranged in the through-openings and wherein the sections of said contact elements containing the contact points (9) project beyond the mounting (18).

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