DE102009013982A1 - Voltage-optimized contact - Google Patents

Abstract

The invention relates to a contact element having a base spring part, wherein the base spring part is formed from a substantially planar base portion and a spring tongue, which are connected to each other via a deflection, wherein in at least one of the sections, a reinforcing member is mounted.

Description

The The invention relates to a contact spring or a Contact element, which in particular for contacting a contact zone a card reader, preferably a smart card reader such as smart card connectors, or the contacting of electrical components such of microbatteries and microphones.

The Invention relates to it on a smart card reader, especially a SIM card reader for contacting SIM cards of small design.

Smart Card connectors and smart card readers become a considerable amount, for example used in mobile phones. Smartcard card reader, in particular SIM card card readers are becoming an ongoing trend towards miniaturization subjected. This concerns in particular the low construction height and the Extension of the contacting devices in height, that is the height of the SIM card reader.

at the well-known SIM card reader, also called a card reader or Contacting units can be designated, are mainly contact elements used, either by snapping into a plastic body or be held by molding with plastic. This type of contact calls, regarding the manufacturability, a relatively high total thickness of the contacting. In particular, while ensuring the Function of good spring properties, but with relatively short spring travel, does this to the fact that card readers in their height in the state of the art typically used materials for contact springs no longer reduce further. This is at a height of less than a millimeter the total height the card reader and it is the designs in the state to consider the technique, which have this minimum height.

One particular problem is the problem of bending stress and notch stress of a contact spring element. It is necessary to stress optimized Constructs to provide, in particular, an optimization causes the bending stress in the range of spring forces occurring. The permanent spring load should not be affected, this means, On average, it is necessary for such contact between 5,000 and 10,000 spring loads during its life and endures the occurring notch and bending stresses are not negative or interfere with the operation of the contact. Especially in the area of a bending accident occur the problems the bending stresses in a contact element to day.

Become in particular punched, so notches in the contact spring used, so high voltage spikes, depending on the Notched form, the so-called notch tensions. At stress can be There are defects such as cracks, which ultimately cause failure condition the component and lead to breakage at the notch point. alternative can in place of the reinforcing element as well a recess in the geometry of the contact spring are fitted. Preferably, this is a optimized notch shape selected, reduce which voltage peaks of the contact element.

One embodiment The present invention positions a corresponding one Notch shape in the area before the deflection in the upper part of the base section. Preferably, the recess is formed so that it an elongated opening, essentially on one side, namely the bend of the spring element facing side, over a notch stress-optimized contour in its inner radius acts.

Of the opposing Portion of the recess is formed by a substantially semicircular opening, the one-piece overflows into the area of the notch optimized contour. For this the method of train triangles is used, which on the following Method is based. There is a line in the recess symmetrical pulled through the recess, along this line runs the first Contour line of construction using the example of a 90 ° corner with the walls a 45 ° angle forms. In the middle of the contour line is now a new contour line set, this time with an angle of 22.5 °, ie half the angle of first train line.

These The procedure is repeated once more with an angle of 11.25 °. The now resulting surface between the lines and the edge of the recess is filled up. The remaining kinks are rounded. The contour now to be preserved has virtually no power surges and is so far on the place suitable contact in contact.

The invention is therefore an object of the invention to provide a contact element, in particular for contacting a contact zone of a SIM card, which makes it possible to realize a SIM card reader with the lowest possible height while optimally designing the spring characteristics of the contact spring with relatively short spring travel. Under construction height of the card reader is the effective height H1 to understand, which is responsible for the contact geometry and the spring properties. Also, the extent in the XY plane (perpendicular to the height) is in the sizes order of a few millimeters and corresponds approximately to the contact zone of a SIM card.

The Invention has also set itself the goal of a smart card connector with low height using the contact elements according to the invention ready to deliver.

A Another object of the present invention is to provide a contact according to the invention scalable in addition to its spring properties, that means, provide a holding geometry such that the contact equally in smart card reader another type or design can be used with, in particular the contact tip can also be brought into a contacting position can without a higher completely new contact to have to provide.

task Therefore, it is the object of the present invention to provide a contact element to put, which in his pen area with the least possible height realized, but at the same time in different applications, speak different installation situations, application can find. As the level at which a card is to be contacted, depending on the application and design, for example, the mobile phones is different, it is desirable that Training one as possible thin Make contact spring part so that this in a variety of similar Applications can still find application with minimal height.

According to the invention is a Contact element provided, which allows contact between a Printed circuit board and a smart card, in particular a SIM card manufacture, wherein the contact element in about the height of the card reader corresponds and its spring characteristics by its special constructive Design receives.

Thus, according to the invention also provided a contact element, which allows contact between a remote circuit board and a smart card, in particular produce a SIM card, wherein the contact element in about the height the card reader has, but about an enlarged according to the removal of the circuit board connection section features.

In accordance with the invention the contact element has a reinforcing section, which scales the spring properties and the spring travel of the contact, so in height and location customizable by simple means. That the amplifying section of the contact must be designed such that on the one hand the Resetting properties of the Spring contact optimally preserved, on the other hand, conditionally due to the reduced height, sufficient Spring force is generated by the contact.

According to the invention the contact element thus from an upper region, which with the Task is afflicted, if possible minimal in its height to be trained and a lower, trained as a base part Area that needs to be scalable in size, so that a contact element is obtained in combination of the two tasks, which has minimal construction height in its spring area and by its height scalability used in different positions relative to its mounting position can be.

The inventive contact element consists therefore of a basic spring part, which with a reinforcing element is trained. The contact element is therefore made of a base section, a deflection portion and a spring portion, thus can over the configuration of the deflection and base section in connection with reinforcing elements a scalable contact, or a scalable contact spring, provided according to the invention become. This is basically a reduced overall height H1 for a formed by the contact elements according to the invention Smartcard connector possible, up to the height limited to the entire contact. Frequently Also, holes in a printed circuit board are required to make parts of a PCB Contact element, if this with a smart card in Connection stand. Such holes and holding means are by the particular shape of the contact elements according to the invention anyway largely unnecessary.

Preferably the spacer element of the contact element is formed scalable. Alternatively, the contact but also over several deflection sections feature, which in addition the height define the total contact and it can, for example, a number of deflecting sections, starting from the base to the spring section, between, as it were, arranged in series. Depending on the number of Reversing sections increased thus the total height the contact and thus the total height of the card reader. The base, the deflection section and the contact spring are usually made of a metal strip material stamped out. The spacer is preferably also off a metal strip material and preferably in one piece with the contact element educated. The reinforcing element may be made of the same or a different material with desired mechanical properties are provided.

Preferably, the reinforcing element is adapted to the geometry of the contact spring. For example, the reinforcing element in the inner region of the base portion of the Kontaktfe are located, so that it comes to a stiffening of the spring element, that is the contact spring. Alternatively, in the region of the deflection, a reinforcing element, for example, a bead be attached, which is attached when punching and forming the contact spring with. Alternatively, an additional free spring element between the spring portion of the contact spring and the base may be arranged so that the spring forces and the restoring forces resulting from actuation are influenced by the additional reinforcing element.

critical however for The idea of the invention is the formation of the reinforcing element in Area of contact.

Further Advantages and expedient designs The invention are described in the further claims, the figures, the description and the description of the figures, the figures showing:

1 a plan view of a contact element according to the invention;

2 the side view of in 1 illustrated contact element;

3 a view of the reinforcing element of in 1 and 2 shown contact element;

4 a perspective view of the contact according to 1 . 2 . 3 ;

5 A second embodiment of the invention in side view;

6 a perspective view according to the 5 the contact element according to the invention;

7 a plan view of a third embodiment of a contact element;

8th a side view of the contact element according to 7 ;

9 a perspective view of the contact element according 7 and 8th ;

10 a further embodiment of a contact element according to the invention;

11 a side view of the contact element according to 10 ;

12 a perspective view of the contact according to 10 and 11 ,

In the 1 to 4 a first embodiment according to the present invention is shown, wherein a contact element 1 is shown, which as Grundfederteil 2 is trained. The basic feather part 2 includes a substantially planar base portion 3 , which is formed substantially rectangular with its outer contour. To the base section 3 closes a U-shaped deflection section 4 over substantially the entire width of the base section 3 at. In the extension of the deflection section 4 there is a spring tongue 6 , to which, in turn, the actual contact section with the contact tip 7 followed. It can be clearly seen that starting from the deflection 4 up to the contact point 7 the width of the contact element tapers and in the region of the spring tongue 6 almost trapezoidal decreases and thereon a miniaturized contact tip 7 is arranged as spoon contact tip. The Kotaktkuppe 7 has a slightly raised contact zone 10 as clearly shown in 2 is apparent. The contact zone 10 so far protrudes slightly over the curved contour of the contact tip 7 upwards. The basic feather part 2 is insofar by bending a punching plate in the corresponding basic shape of the contact element 1 made by attaching to the base section 3 a first essentially bent by 180 ° deflection section 4 is formed, which in a tapered spring tongue portion 6 passes, which is substantially parallel to the base section 3 runs. In the course of the spring tongue 6 cut with a first Kontaktkuppenab 7a in their orientation away from the base section 3 bent, then around the contact zone 10 a back bend towards the base section 3 in the area of the contact crest section 7b to experience. In this respect, the two Kontaktkuppenabschnitte 7a . 7b oriented at an angle of about 100 ° to 120 ° to each other. The base section 3 has a geometrically formed reinforcing element 5 in the form of a defined recess in the base section 3 , This means the reinforcing element 5 is in this embodiment as a punched in the base section 3 educated. The reinforcing element 5 is shaped such that it is in the front right part, according to 3 , has a substantially semicircular geometry, which is to be seen in the further course, so to speak to the left as an extension of two parallel edges and then, however, does not end in a further semi-circular section, but a special symmetrical cut-out 11 follows. This contour is formed by the method of the tensile triangles, as described previously in the description. This arises as in 3 can be seen, characterized in that from a rectangular round die, at its four corners, one notch 12 is trained. The corners 12 correspond to the notches, so to speak 12 , However, the method of the train triangles is only applied to the in 3 left two notches 12 applied. Every notch will symmetrically bridged by a thoughtful pull rope. Along this rope runs the first contour line of the construction, which forms an angle of 45 ° with the two walls. In the middle of each contour line, ie the imaginary connections, now a new pull rope is attached or a new Zugdreieck. The second application of the draw triangle halves the angle, ie from 45 ° to 22.5 °. This procedure is repeated one more time at an angle of 11.25 ° and so on.

The resulting surface between the tension cables and the actual component is still so to speak refilled. The resulting kinks are rounded, however, so that a contour is created, which the voltage spikes and thus the bending stresses in particular the problems of the core tension clearly reduced.

In 5 is the contact element according to 1 to 4 formed such that the base portion 3 a spacer element 3 a spacer element 8th is appropriate.

The spacer element 8th is approximately in the width of the base section 3 formed and has a substantially U-shaped cross-section. The end of the U-shaped cross-section is located below the base section 3 , immediately near the reinforcing element 5 , just before the formation of the deflection section 4 , Therefore, the contact may be 1 with its basic feather part 2 especially with the base section 3 on the end of the spacer element 8th additionally support. Task, however, the spacer element 8th is it that actual basic feather part 2 with its height H1, which must represent the minimum height of the contact element to bring to a desired altitude H2 within a device. Since different installation situations allow, on the one hand, minimal contact space for contact within a certain geometrical construction condition, this must always, but not necessarily, always be at the bottom of a component. It is therefore desirable to contact according to 1 to 4 , which there only from the Grundfederteil 2 exists to modify such that this in different installation situations due to the attached spacer element 8th Application can be found.

In 6 you can see the perspective view of the contact element 1 out 5 , Clearly recognizable is the shape of the reinforcing element 5 , which was also formed here by the method of Zugdreiecke.

Another embodiment is 7 refer to.

The difference from the first embodiment is that the spacer element 8th is formed with its height H2 as a V-shaped spring element, which could basically also have a plurality of such substantially zig-zagging spring contours.

In 8th consists of the spacer element 8th from two spring tongues 13 . 14 , which are connected to each other at one end. To the spacer element 8th and to the spring tongue 13 is the spring tongue 6 formed, in its expression in about the spring tongue 6 from the first embodiment corresponds. By increasing the length of the spring with the same size, since here the bending radius is eliminated, it comes on the one hand to a reduction of the overall height and on the other hand to a reduction of notch stresses and bending stresses. In particular, another reinforcing element 15 attached, which is the connection between the spring tongue 6 and the spring tongue 13 represents.

In the 7 to 9 is however the reinforcing element 5 only not shown.

Another embodiment of the present invention is in the 10 to 12 shown. This in a further embodiment of a special outer contour for preventing rotation in the packaging.

In this case, in addition to the reinforcing element also not shown here 5 the base section 3 in the middle with a heel 16 formed as an increase. Otherwise, the contact in its basic geometric form substantially corresponds to the first embodiment.

In addition, at the outer edge of the base section 3 , which run parallel to each other and are symmetrical, in the middle recesses 17 . 18 molded, which contribute in addition to the desired effect. It can be clearly seen that the base section 3 and the deflection section 4 in about twice the material thickness as the spring tongue 6 is trained.

1

contact element

2

Basic spring part

3

base section

4

deflecting

5

reinforcing element

6

spring tongue

7

contact cusp

7a, 7b

Contact cap sections

8th

spacer

10

contact zone

11

Ausschneidekontur

12

notch

13

spring tongues

14

spring tongues

16

paragraph

17 18

recesses

Claims (15)

Contact element ( 1 ) with a basic spring part ( 2 ) wherein the base spring part ( 2 ) from a substantially planar base section ( 3 ) and a spring tongue ( 6 ) is formed, which via a deflection section ( 4 ) are interconnected, characterized in that in at least one of the sections a reinforcing element ( 5 ) is attached. Contact element ( 1 ) according to claim 1, characterized in that the base section ( 3 ) and the spring tongue ( 6 ) extend substantially parallel to each other and the spring tongue ( 6 ) via a contact tip ( 7 ) at its end. Contact element ( 1 ) according to claim 1 or 2, wherein the reinforcing element ( 5 ) in the base section ( 3 ) is trained. Contact element ( 1 ) according to one of the preceding claims, characterized in that the reinforcing element ( 5 ) is an opening with an inner circumferential cut-out contour ( 11 ). Contact element ( 1 ) according to one of the preceding claims, characterized in that the reinforcing element ( 5 ) is formed with its opening so that at least a part of the opening in its cut-out contour ( 11 ) is formed such that it follows in accordance with a continuously changed radius. Contact element ( 1 ) according to one of the preceding claims, characterized in that a part of the cut-out contour ( 11 ) is formed by a part of a semicircle. Contact element ( 1 ) according to one of the preceding claims, characterized in that the part which is formed as a semicircle, by means of two straight sections at the formed with changing radius portion of the cutting contour ( 11 ) and thus the entire inner contour of the cutting contour ( 11 ) forms the opening. Contact element ( 1 ) according to one of the preceding claims, characterized in that the part of the cut-out contour ( 11 ), which is formed with a changing radius, is carried out by the method of the tensile triangles, wherein at least three bisecting traction triangles part of the cutting contour ( 11 ) in this section at at least one point. Contact element ( 1 ) according to one of the preceding claims, characterized in that the contact element ( 1 ) via a spacer element ( 10 ), which at the base section ( 3 ) is attached. Contact element ( 1 ) according to one of the preceding claims, characterized in that between the spring tongue ( 6 ) and the base element ( 3 ) at least one further spring tongue ( 14 . 15 ) is located. Contact element ( 1 ) according to one of the preceding claims, characterized in that the base section ( 3 ) via a paragraph ( 16 ) in its center such that the paragraph ( 16 ) of the spring tongue ( 6 ) facing side extends. Contact element ( 1 ) according to one of the preceding claims, characterized in that the base section ( 3 ) via two lateral recesses ( 17 . 18 ), which in the area of paragraph ( 16 ) are formed. Contact element ( 1 ) according to one of the preceding claims, characterized in that a reinforcing element ( 5 ) in the region of the deflection section ( 4 ) is arranged on the outside thereof. Contact element ( 1 ) according to one of the preceding claims, characterized in that the reinforcing element ( 5 ) represents a bead. Card reader, comprising at least one contact element ( 1 ) according to one of the preceding claims.