DE8914952U1 - Electrical contact socket for a flat pin - Google Patents

Description

5590/V/wi

Electrical contact socket for a flat pin

The invention relates to a contact socket according to the preamble of claim 1.

In contact sockets of this type, it is known to form the socket-shaped contact part in one piece from a base plate with side walls extending from the side edges and end areas bent in a box shape from these, which overlap the flat pin inserted into the contact part on the side facing away from the base plate and act as spring arms to press the flat pin against the base plate in order to ensure contact with the contact surface. The end areas can be given their shape by rolling up sheet metal tabs that adjoin the sides of the base plate. In order to prevent deformations, particularly when a flat pin is inserted incorrectly into the contact socket, the contact socket and the end areas must be of considerable strength. In the known design, high insertion forces therefore occur, which are caused by the fact that the end areas or the bent side walls have hardly any spring travel. The latter leads to a further disadvantage of the known design, which is that close tolerances must be maintained in the area of the end areas, in particular as far as the distance between the

end areas and the base plate of the contact socket. This makes production much more difficult and a large number of rejects are to be expected.

The invention is based on the object of designing a contact socket of the type specified at the outset in such a way that the flat plug-in contact can be inserted and, if necessary, removed again with a relatively low insertion force.

This object is solved by the features of claim 1.

In the design according to the invention, at least one spring arm is provided as a single piece on the contact socket, which acts transversely on the inserted flat pin and ensures that the inserted flat pin is pressed against the opposite inner wall of the socket. The spring arm can be designed with great elasticity and a large spring travel, so that the socket can be manufactured with relatively large tolerances and therefore more easily, even with a stable design of the socket with relatively thick walls. Due to the flexibility of the spring arm and its relatively large spring travel, relatively small insertion forces can be achieved with secure contact, so that the flat pin can be inserted into the socket smoothly and with ease of handling and can be pulled out again if necessary. In the design according to the invention, the end areas mainly have a guiding function. They can therefore be designed to be more stable, so that if the flat pin is inserted incorrectly, the contact part cannot be damaged so easily, e.g. by bending. Due to the one-piece connection of the at least one spring arm to the contact part or an associated base part, the contact socket can be produced simply, quickly and inexpensively as a stamped/bent part. A further advantage of the design according to the invention is that it does not require a larger construction and therefore with the same cross-sectional size of the socket

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can be realized. A contact socket designed according to the invention therefore fits into standard housing chambers of usual size.

' Advantageous further developments of the invention, which relate to favorable positioning of one or more spring arms and also to a reinforcement of at least one spring arm by the spring arm of an overspring, are described in the subclaims.

The invention is explained in more detail below using preferred embodiments shown in a drawing. Shown are:

Fig. 1 shows a plug contact socket designed according to the invention in plan view,

Fig. 2 the contact socket in side view, partially cut,

Fig. 3 the contact socket in bottom view,
Fig. 4 shows section IV-IV in Fig. 1,

Fig. 5 shows a contact socket of another design according to the invention in plan view,

Fig. 6 shows the contact socket according to Fig. 5 in side view. Left, partially cut,

Fig. 7 The contact socket according to Fig. 5 in the bottom view,

Fig. 8 a part of the contact socket according to Fig. 5 in the side view from the right,

Fig. 9 the section IX - IX in Fig. 5,

Fig. 10-12 show details of modifications to the design of the contact socket according to Fig. 5,

\ Fig. 13 a contact socket according to the connection In yet another embodiment In plan view,

Fig. 14 the contact socket according to Fig. 13 in side view from the left, partially cut,

Fig. 15 the contact socket according to Fig. 13 in the bottom view,

Fig. 16 the contact socket according to Fig. 13 in side view from the right, partially cut,

Fig. 17 the section XVII- XVII in Fig. 13,

Fig. 18 a contact socket according to the invention in a further embodiment in plan view,

Fig. 19 the contact socket according to Fig. 18 in side view from the left, partially cut,

Fig. 20 the contact socket according to Fig. 18 in bottom view,
Fig. 21 shows section XXI-XXI in Fig. 18.

In all designs, the contact socket 1 consists of a shaped or bent sheet metal stamping with a crimp part 2 at the rear end, a transition area 3 adjoining it to the front and a contact part 4 extending from this to the front, to which a spring 5 is held in a form-fitting manner. The crimp part 2 has two rear insulation claws 6 and two front wire claws 7, which are each arranged on both sides of the vertical center plane 8 of the contact socket 1 and are open at the top.

The contact part 4 is formed from an essentially flat base plate 9, which also extends into the transition area 3, and two side walls 12, which are connected to the longitudinal edges 11 of the base plate 9 and are angled upwards at approximately right angles, and end regions 13 which are bent or rolled up towards one another in a box shape and whose free longitudinal edges 14 are spaced a distance a from one another. In the area of the free longitudinal edges 14, the end regions 13 are bent or recessed, whereby a plug-in shaft 15, which is open at the front and back, is formed for a flat plug pin 16, which is indicated in Fig. 2 in this embodiment, which is delimited on the underside by the base plate 9, on the side by the side walls 12 and on the top by the longitudinally extending end strips 17, which are preferably bent in parallel to the base plate 9.

At the rear ends of the end regions 13, the side walls 12 are designed to be lower towards the rear, so that steps 18 are formed on both sides. From these steps 18, the side walls 12 extend a little way to the rear with longitudinal edges 19 parallel to the base plate 9, and then converge obliquely towards a neck having the adhesive claws 7, whereby the transition region 3 is stiffened.

In the base plate 9, there is one central spring arm 21 or two spring arms 21 arranged symmetrically off-centre (only shown in Fig. 2 and 3), each of which is formed by a U-shaped recess or cutout 22 and is bent into the plug-in shaft 15 in the shape of a tongue. The distance b between the spring arms 21 is approximately adapted to the distance a between the end strips 17, so that the spring arms 21 lie under the associated end region 13. The spring arms 21 begin slightly behind the steps 18 and extend forwards beyond the longitudinal center of the end regions 13, designated 23, ending at a distance c from the front edge 24 of the contact part 4. In the area of the longitudinal center 23, the spring arms 21 are bent by transversely running curves.

axes and then bent back again in a rounded manner, resulting in transverse beads 25 and inclined ramps 26 extending forwards and diagonally downwards from these. In the area in front of the ramps 26, the base plate 9 is also bent in or up transversely in the shape of a roof or bead, resulting in introduction bevels 27 at the front end of the base plate 9, which guide the inserted flat pin 16 onto the inclined surface of the inclined ramp 26. These introduction bevels 27 are opposite introduction bevels 27a at the end areas 13, which are formed by convexly bent or cut edge strips 17.

The spring arms 21 are each supported on the outside by an overspring arm 31 of the overspring 5, which is placed and locked or clamped onto the contact part 4 transversely to the longitudinal direction of the contact socket 1. In the present embodiment, the overspring 5 is U-shaped in cross section with two side legs 32 and a web wall 33 connecting them. The overspring 5 is placed or plugged onto the contact part 4 of the contact socket 1 from below, with its web wall 33 resting on the lower surface of the base plate 9. At the points specified by the recesses or cutouts 22, U-shaped recesses or cutouts 34 are also provided in the web wall 33, which are open towards the rear and thereby form the tongue-shaped or strip-shaped overspring arms 31, which extend forwards on both sides of the longitudinal center plane 8 and are also spaced apart by the distance b from one another. The bases 35 of the overspring arms 31 are located at the bases 36 of the spring arms 21, and they are at a distance e from the rear transverse edge of the web wall 33, whereby the overspring arms 31 each extend approximately to the associated transverse bead 25 and in the present design rest with the overspring arm ends 37 on the rear transverse edge of the associated transverse bead 25. Preferably, the overspring arm ends 37 are slightly bent upwards at a short distance from their tips, so that only the overspring arm ends 37 rest on the spring arms 21, while the remaining area of the overspring arms 31 is surrounded by the spring arms.

men 21 is slightly spaced apart.

The overspring 5 is held or clamped to the contact part 4 in a form-fitting manner at at least two points opposite one another with respect to the longitudinal center plane 8. For this purpose, bending tabs protruding from the overspring 5, which is also formed by a one-piece punched/bent part, can be used, which are bent around associated edges of the contact part 4. In the design according to Fig. 1 to 4, four bending tabs 38 are provided, which project beyond the height f of the side legs 32, which is approximately adapted to the height h of the contact part 4, and are bent around longitudinal edges of the contact part 4, as can be clearly seen from Fig. 4. At the rear end of the overspring 5, the bending tabs 38 are bent around the longitudinal edges 19 of the side walls 12. At the front ends, the bending tabs 38 are bent around longitudinal edges 39 of the side walls 12, which are formed by rectangular cutouts 41 at the outer corners of the end regions 13 and form front steps 42 comparable to the steps 18. The positive holding of the overspring 5 on the contact part 4 in its longitudinal direction is achieved by the bending tabs 38 gripping the transverse edges 43, 44 of the steps 18, 42 in front of and behind one side.

The recesses or cutouts 34 forming the spring arms 31 are connected to one another by a transverse section 45, so that a W-shape is formed for a common recess or cutout 34. As a result, a tongue 30 extending opposite to the spring arms 31 is formed between the spring arms 31, which extends backwards and is bent out at an angle and, due to friction or locking, can serve as a securing part for the contact socket 1 when it is inserted into a chamber of a housing.

In front of the recesses or cutouts 34, rectangular cutouts 46 are provided in the web wall 33 at a distance g from each other, the dimensions of which are larger than the front ends of the over-spring arms 31 and are positioned

are such that the spring arm ends 47 or the ramps 26 can enter the cutouts 46 when the flat pin 16 is inserted.

Since the contact socket 1 and the overspring 5 are each a one-piece stamped/bent part, the ^thicknesses α λ , dl are each the same, whereby the thickness dl of the overspring 5 is slightly less than the thickness d of the contact part 4.

In the P. . designs according to Fig. 5 to 21, in which identical parts are designated identically or with identical reference numerals, differ from the previously described design in the design or arrangement of the spring arms 21, the overspring 5 and their positive mounting on the contact part 4.

The spring arms 21 are arranged and formed here in the area of the end regions 13 opposite the base plate 9, which in the design according to Fig. 5 to 8 are not bent or recessed, but are formed by end legs 48 extending straight towards each other, which results in an essentially square box profile for the contact part 4. The spring arms 21 are cut out of the end legs 48 in a comparable manner and bent into the plug-in shaft 15, whereby here, due to the gap 49 present between the end regions 13, only angular recesses or cutouts 51 are required in the end legs 48. In the present design, the distance b between the spring arms 21 is larger than the gap 49, which means that cutting edges 50 are also required on the inner longitudinal edges of the spring arms 21.

The spring arms 21 initially converge due to their bending up to a contact transverse plane 52, which is shifted somewhat further forwards compared to the longitudinal center 23 according to Fig. 1 to 3, but extends within the steel shaft IS. From the transverse plane 52, the spring arms 21 diverge forwards, whereby inclined insertion ramps 26 are formed. The base plate 9 is in the

in Fig. 7 with 53, pressed in parallel or convergently towards the front, whereby insertion bevels 27 are also formed on the front edge of the plug-in shaft 15. In addition, contact cams 54 are provided in the contact transverse plane 52 below the spring arms 21, which are preferably formed by further indentations in the base plate 9 made from below.

In this embodiment, supporting end regions 13a are therefore only provided in the rear region of the side walls 12.

A further difference in the design according to Figs. 1 to 4 is that the overspring 5, which is U-shaped in cross section and adapted in cross section to the box shape of the contact part 4, is not placed on the contact part 4 from the underside but from the top, so that the web wall 3? of the overspring 5, which forms an overspring base, is placed on the end regions 13a or on the side walls 12 which are the same height as the end regions 13a (see height hl). The form-fitting mounting of the overspring 5 also takes place in the area of the side walls 12. The overspring 5, which is also U-shaped in cross section, is placed on the contact part 4 from the top, rather than from the underside, so that the web wall 3? of the overspring 5, which forms an overspring base, is placed on the end regions 13a or on the side walls 12 which are the same height as the end regions 13a (see height hl). The overspring arms 31 adapted to the spring arms 21 are bent downwards from the web wall 31 forming a cover plate, whereby they are bent in a slightly convex manner so that the overspring arm ends 37 in the area of the contact transverse plane 52 rest on the outside or top of the spring arms 21 and thus support them outwards. In order to avoid jamming, it is advantageous to bend the overspring arm ends 37 slightly outwards in the contact area, preferably in a rounded manner.

In the present embodiment, the U-shaped recesses or cutouts 34 forming the overspring arms 31 also merge into one another in a W shape, but the resulting rearward-facing central longitudinal tongue is cut away in its foot area by the cutting edge 55, whereby a spring tongue 30 on the overspring 5 is omitted. Instead of or in addition to a

C ·

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In the embodiment according to Fig. 5 to 9, one or two spring tongues 30.1 arranged on both sides of the central longitudinal plane 8 can be cut out and bent out of the base plate Q in a similar manner, as is shown in Fig. 6.

In this embodiment, too, the bases 35, 36 of the over-spring arms 31 and the spring arms 21 are arranged at approximately the same distance e from the rear edge 28 of the over-spring 5. Since the over-spring arms 31 are shorter than the spring arms 21, a transversely extending front web wall part 33a remains on the web wall 33 in the upper leather 5, which is connected to the rear web wall part 33b by web wall edges 33c running on both sides of the recesses or cutouts 34, and which has an inwardly rounded or obliquely downwardly bent edge leg 57 at the front with an oblique or rounded insertion bevel 27a for the plug-in shaft 15, which is opposite the bottom-side insertion bevel 27. The overspring arms 31 and the free edge of the edge leg 57 overlap each other so that when a flat pin 16 is inserted, it cannot hit the front edge of the spring arms 21.

The positive mounting for the overspring 5 is formed by at least two locking arms 61 with locking lugs 62 arranged on both sides of the longitudinal center plane 8 in the edge area, which are formed on the side walls 12 by U-shaped recesses or cutouts 63, extend towards the side facing away from the web wall 33 and are slightly bent out. When the overspring 5 is placed on, the locking arms 61 are elastically bent by the side legs 32 and then they fit into adjacent locking edges 64 forming locking cutouts 65 in the side legs 32.

Fig. 10 shows locking arms 61 in structural or functional reversal, ie here the recesses or cutouts 63 and

I ' I I &igr;&igr; I Ii &igr; ·

the locking arms 61 are arranged on the side legs 32 of the overspring 5, whereby the locking arms 61 extend in the direction of the web wall 33 and the locking lugs 62 protrude slightly from the inside of the side legs 32. The locking cutouts 65, on the other hand, are located in the side walls 12 of the contact part 4 in such an arrangement that when the overspring 5 is placed on the contact part 4, the locking arms 61 are bent out through the side walls 12 and then snap into the fastening cutouts 65 so that the locking lugs 62 are immediately in front of the locking edges 64.

In the embodiment according to Fig. 11, instead of locking arms 61, bending tabs 38 are provided, which extend from significantly shortened side legs 32 of the overspring 5 or can extend directly from the web wall 33, whereby side legs

32 can be omitted. In their initial position, these bending tabs 38 extend along the side walls 12, i.e. approximately at right angles to the web wall 38. Transversely adjacent to the bending tabs 38 there are locking recesses 66 in the side walls 12, into which the bending tabs 38 can be bent, overlapping the locking edges 67 facing the web wall 33, whereby the positive holding in the transverse direction is formed. In the longitudinal direction of the contact element 1, the positive holding is achieved by the bending tabs 38 being approximately closed between the transversely extending boundary edges 68 of the locking recesses 66. The locking arms 61 according to Fig. 10 and the bending tabs according to Fig. 11 can be bent by a transverse movement parallel to the base plate 9 (arrow 69).

A design comparable to the design according to Fig. 11 is shown in Fig. 12. In this design, the locking recesses 66 extend to the web wall

33 or the end areas 9 facing away from the base plate 9, whereby it is possible to bend these bending tabs 38 by a transverse or perpendicular to the base plate 9 into the

Bending tool that can be moved in the direction of movement indicated by arrow 69a for example, to be bent into the shape of a stamp, whereby these blades 38 can be bent into a C-shape.

In the above-described designs, the arrangement of the overspring 5 results in an increase in the cross-section of the contact part, namely according to Fig. 4 on the base plate 9 and the side walls 12 and according to Fig. 9 on the side walls 12 and on the end areas 13. If a predetermined cross-sectional size is to be assumed, then these designs inevitably lead to a reduction in the cross-section of the contact part 4. In the designs according to Figs. 13 to 21, oversprings 5 are provided which do not lead to an increase in the cross-section of the contact part 4. These two designs are similar to the design according to Fig. 5 b.ls 9 with regard to the contact part 4, namely with spring arms 21 extending from the end areas 13 and over-spring arms 31 supporting them from the outside. The base plate is pressed in in the parallel position in the area designated 53 and the spring arms 21 extending from the end areas 13 are shorter and cut free by L-shaped recesses or cutouts 34, so that end area parts 13a, 13b also exist on the rear and front edge 24 of the end areas 13, whereby the front end area parts 13b can be rolled up with edge legs 71 extending transversely to the base plate 9, which can be designed with insertion bevels 27a at the front end in order to facilitate the insertion of the flat pin 16 with the opposite insertion bevels 27.

The rear end portions 13a extend essentially parallel to the base plate 9, wherein they are drawn inwards, i.e. towards the base plate 9, with respect to the associated longitudinal edges 72 of the contact part 4, so that their outer sides 73 have an inwardly displaced distance j from the outer plane AE or from the top of the contact part 4.

In this embodiment, the overspring 5 is a substantially

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flat structure that - seen from above - extends within the boundary edges of the contact part 4, i.e. the 'air spring 5 does not protrude beyond the side walls 12,' whereby it can be placed or placed transversely to the contact element 1. The overspring 5 has an overspring base 74 that extends essentially parallel to the base plate 9, from which the overspring arms 31 protrude forwards in a fork or tongue shape on both sides of the longitudinal central axis 8 and a central support leg 75 extends backwards essentially obliquely to the base wall 9, which rests against the base plate 9 with a certain pre-tension, while the overspring base 74 rests on the outer sides 73 of the end region parts 13a that are pressed in opposite the longitudinal edges 72. On a longitudinally extending area el that is smaller than the length e of the end area parts 13a, end area leg parts 13al protrude from the longitudinal edges of the end area parts 13a, which lie against one another with abutting edges 25 in the longitudinal center plane 8. The end area leg parts 13a 1 are bent outwards or upwards and pass through the overspring base 74 in correspondingly dimensioned elongated holes 76. The overspring base part 74a located under the end area leg parts 13al can be separated by transverse incisions and bent slightly parallel inwards. In a prefabricated form that can be seen in Fig. 17, the end area leg parts 13al are bent outwards, i.e. they extend approximately perpendicular to the end area parts 13a. In this position, the overspring 5 can be placed with its elongated holes 76 on the end region leg parts 13al and against the end regions 13a. The end region leg parts 13al are then bent towards each other, whereby the overspring 5 is secured against lifting off. The arrangement is such that in this assembly position the support leg 75 presses against the base plate 9 with a certain tension and the overspring arms 31 press against the spring arms 21 with a certain tension. This implies a reaction force (see arrow) with which the overspring base part 74a is pressed against the end region leg parts 13al.

In the longitudinal direction, the overspring 5 is secured in a form-fitting manner on the one hand by the contact of the overspring arm ends 37 on the associated converging overthreader arm 21 and on the other hand by convex bends 77, 78, which are located immediately in front of and behind the end region leg parts 13a 1. The width k of the overspring base 74 is adapted to the distance between the beads formed by the bending of the end regions 13a on the longitudinal edges 72.

To stabilize the end region parts 13a, in particular when pressing in the end region leg parts 13a 1, support legs 81 are bent against the base plate 9 at the rear edges of the end region parts 13a, which extend up to the base plate 9 and can thus be supported on the base plate 9.

In the embodiment according to Fig. 18 to 21, the end region parts 13a are also bent parallel to the base plate 9 with respect to the longitudinal edges 72, with edge leg parts 83 being bent approximately at right angles to the base plate 9 from their mutually directed edges, which can be supported on the inside of the base plate 9 and are therefore dimensioned accordingly long. In the middle longitudinal region, locking lugs S4 project transversely from the mutually directed edges, which are formed by U-shaped recesses or cutouts 85 in the edge leg parts 83 and remain in place when they are bent. The overspring base 74 resting on the bent outer surfaces 73 has a central, longitudinally extending downwardly folded outward bend 86, the diameter of which is adapted to the distance m between the edge leg parts 83 and which has cutouts 88 in both fold walls 87 into which the locking lugs 84 fit and thus hold the overspring 5 on the contact part 4.

In the embodiments according to Fig. 13 to 21, the base plate 9 has a parallel indentation E in the area 53, so that a large contact surface is created for the inserted flat pin 16, see Fig. 16 and 19.

Claims (1)

5590/V/wi EXPECTATIONS 1. Electrical contact socket for a flat plug pin, consisting of a connection part arranged at its rear end, with which it can be connected to a conductor wire or the like, a socket-shaped contact part arranged at the front end and a transition area connecting the connection part to the contact part, the contact part having a substantially flat bottom wall, from the side edges of which side walls are upright and end areas adjoining these are bent in a box shape and delimit a flat socket for the flat plug pin that is open at the front, characterized, that at least one strip-shaped spring arm (21) extending along the bushing is cut out in an L- or U-shape from the base plate (9) or from the end regions (13) and bent obliquely into the bushing (15). 2. Contact socket according to claim 1, characterized in that two spring arms (21) are provided on each side of a longitudinal center plane extending at right angles to the base wall (9), in particular arranged in a mirror-symmetrical manner. 3. Contact socket according to claim 1 or 2, characterized in that the spring arms (21) extend forwards with their free ends and in the region of the spring arm ends there is an insertion slope formed by roof-shaped bent back end legs (26) is provided for. 4. Contact socket according to claim 3, characterized in that introduction rails (27, 27a) are arranged on the socket in front of the free ends of the spring arms (21) in the region of the base plate (9) and the end regions (13). 5. Contact socket according to claim 4, characterized in that the guide bevel (27) on the base plate (9) is formed by an indentation (E) with a contact surface for the flat plug pin that is parallel or inclined to the base plate (9). 6. Contact socket according to claim 5, characterized in that the insertion bevel (27a) is formed by edge legs (71) of the end regions (13) which are angled in the direction of the base plate (9), the front ends of the edge legs (71) being beveled inwards. .7. Contact socket according to one or more of claims 1 to 6, characterized in that an overspring (5) is attached to the outside of the contact part (4), preferably in a form-fitting manner, which has overspring arms (31) present in the number of spring arms (21) which support the spring arms (21) on the outside. 8. Contact socket according to claim 7, characterized in that the overspring (5) has a plate-shaped overspring base (33, 74) which sits on the bottom wall (9) or on the end regions (13) and from which the overspring arms (31) extend and are bent obliquely. 9. Contact socket according to claim 7 or 8, characterized in that the spring arms (31) extend forwards with their free ends. 10. Contact socket according to one or more of claims 7 to 9, characterized in that the end regions (13) are divided by the L- or U-shaped recesses or cutouts (34, 34a) for the spring arms (21) into end region parts (13a, 13b) arranged in the rear region and in the front region of the bushing (15). 11. Contact socket according to one or more of claims 8 to 10, characterized in that the expansion areas (13, 13s, 48") extend substantially parallel to the base plate (9). 12. Contact socket according to claim 11, characterized in that only in the rear region of the intact portion (4) extending end regions (13a) are provided, which are bent approximately parallel to the base plate (9) by a dimension (J) which is equal to or greater than the thickness of the overspring base (74). 1?, Contact socket according to claim 12, characterized in that the end regions (13a) have leg projections (13al) on their mutually facing edges, which pass through holes or cutouts (76) in the over-spring base (74) from the inside to the outside and are bent towards the outside of the over-spring base (74). 14. Contact socket according to claim 13, characterized in that the area of the spring base (74) over which the leg projections (13al) overlap is bent towards the base plate (9). 13. Contact socket according to claim 13, characterized in that a distance (m) is provided between the mutually facing edges of the end regions (13a), and the spring arm base (74) has a central, fold-shaped bend (86) extending in the longitudinal direction and enclosing the distance (n), with locking lugs (84) projecting from the mutually facing edges of the end region parts (13a), which fit into cutouts (88) in the side walls (85) of the bend (86). 16. Contact socket according to claim 15, characterized in that edge legs (83) are connected to the mutually facing edges of the end region parts (13a), which preferably extend as far as the base plate (9) and the locking lugs (84) are formed by U-shaped recesses or cutouts (85) in the edge legs (83), and that preferably the front ends of the edge legs (83) form a stop for limiting the insertion movement of the flat plug pin (16). 17. Contact socket according to one or more of claims 7 to 16, characterized in that at the rear end of the spring base (74) a leg (75) bent towards the base plate (9) is bent, in particular obliquely backwards, which preferably rests against the base wall (9) with tension. 18. Contact socket according to claim 13 or 17, characterized in that the spring base (74) is convexly curved in front of and/or behind the leg projections (13al). 19. Contact socket according to one or more of claims 7 to 18, characterized in that the overspring (5) with side legs (32) overlapping the side walls (12) of the contact part (4) is U-shaped in cross section. 20. Contact socket according to claim 19, characterized in that locking arms (61) formed on the side walls (12) by U-shaped recesses or cutouts (63) and slightly bent out are formed with locking seams (62) which engage behind locking edges (64) formed by cutouts (65) on the side legs (32) of the overspring (5). 21. Contact socket according to claim 19, characterized in that locking rings (61) formed by U-shaped recesses or cutouts (63) are formed on the side legs (32) of the overspring (5), which are slightly bent and engage behind locking edges (62) formed by cutouts (65) on the side walls (12) of the contact part (4). 22. Contact socket according to one or more of claims 7 to 19, characterized in that bending tabs (38) protrude from the free side edges of the over-spring base (5) or from the free side edges of the side legs (32), which are bent behind locking edges (67) on the side walls (12), which are formed by correspondingly large cutouts (66) in the side walls (12). 23. Contact socket according to claim 22, characterized in that the cutouts (66) extend into the edge region of the wall (9) of the contact part (4) opposite the spring base (33). 24. Contact socket according to claim 19, characterized in that bending tabs (38) project from the free side edges of the side legs (32), which are bent in so as to engage behind the free side edges (19, 39) of the side walls (12). 25. Contact socket according to claim 24, characterized in that the free side edges (19, 39) are recessed by recesses (43, 44) and/or steps (18, 42). 26. Contact socket according to one or more of claims 20 to 25, characterized in that two or four locking arms (61) or bending tabs (38) are provided opposite one another in a central transverse plane of the socket or the overspring (5). Y/. Contact socket according to one or more of claims 8 to 26, characterized in that the spring base (33) extends approximately from the rear end of the socket to approximately its front end and the spring arms (31) are formed by U-shaped recesses or cutouts (34). 28. Contact socket according to claim 27, characterized in that end region parts (13a) are provided only in the rear region of the socket, the over-spring base (33) rests in the front region of the socket on the free longitudinal edges of the side walls (12) of the socket and preferably has on its front edge an obliquely bent leg (57) forming an insertion bevel (27a). 29. Contact socket according to one or more of claims 18 to 24, characterized in that the overspring base (33) is divided by the recesses or cutouts (34) forming the overspring arms (31) into overspring base parts (33a, 33b) which are connected to one another by the side legs (32) or edge regions (33c). 30. Contact socket according to one or more of claims 8 to 29, characterized in that the overspring arms (31) are cut out by a W-shaped recess or cutout (34) and the tongue (30) formed between the inner flanks of the recess or cutout (34) is bent obliquely backwards. 31. Contact socket according to one or more of claims 1 to 30, characterized in that a tongue formed by a U-shaped recess or cutout and bent outwards and obliquely backwards is formed on the bottom wall (9). 32. Contact socket according to one or more of claims 11 to 31, characterized in that support legs (81) are arranged on the rear transverse edges of the iSndberelche (13a) which are angled to the base plate (9) and preferably supported thereon. 33. Contact socket according to one or more of claims 1 to 32, characterized in that the contact socket (1) and the spring cover (5) are one-piece stamped/formed parts made of sheet metal.