Abstract:
The invention relates to a press-fit pin ( 1 ) made from wire material for electrical contacts, in particular plug-in connectors. When using press-fit pins ( 1 ) made from wire material the problem of the tips ( 23 ) of the press-fit pins ( 1 ) being damaged by the press-fit tool has previously occurred. To be able to support a tool on press-fit pins ( 1 ) made from wire material without the tips ( 23 ) being damaged the press-fit pin ( 1 ) made from wire material is provided according to the invention with a shoulder element ( 3 ).

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates to a press-fit pin made from wire material for electrical contacts, and for use particularly in plug-in connectors. 
       BACKGROUND 
       [0002]    To produce solder-free electrical connections it is known to use press-fit pins made from wire material. Press-fit pins are pressed into printed circuit boards or plastic housings with the aid of tools and are used as part of the plug-in connector. 
         [0003]    The press-fit tools exert high forces on the pin, for which purpose they have to be supported at their pin tips. In the process the problem of the pin tips being damaged often occurs. 
       SUMMARY 
       [0004]    An object underlying the invention, among others, is consequently to provide a press-fit pin made from wire material which can be pressed-in without it being damaged. 
         [0005]    This object and other objects are achieved according to the invention of a press-fit pin which comprises at least one shoulder element. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The invention will be described in more detail by way of example hereinafter using advantageous embodiments and with reference to the drawings. The described embodiments are only possible configurations in which the individual features may however, as described above, be implemented independently of each other or be omitted. In the drawings: 
           [0007]      FIG. 1  is a perspective view of a press-fit pin constructed according to the invention with a compressed location, 
           [0008]      FIG. 2  is a partial perspective view of a press-fit pin constructed according to the invention with an impression, 
           [0009]      FIG. 3  is a perspective view of a plurality of split press-fit pins constructed according to the invention which are framed by a carrier member, 
           [0010]      FIG. 4  is a perspective view of a press-fit pin constructed according to the invention with laterally provided noses, 
           [0011]      FIG. 5  is a perspective view of a plurality of bent press-fit pins which are framed by a carrier member, 
           [0012]      FIG. 6  is a perspective view of a press-fit pin constructed according to the invention and bent in an S-shape, 
           [0013]      FIG. 7  is a perspective view of a press-fit pin framed according to the invention by a ring, 
           [0014]      FIG. 8  is a perspective view of a plurality of press-fit pins notched according to the invention and framed by a carrier member, 
           [0015]      FIG. 9  is a perspective view of a plurality of press-fit pins that, according to the invention, penetrate a flat body, 
           [0016]      FIG. 10  is a perspective view of two press-fit pins surrounded according to the invention by two flat bodies, 
           [0017]      FIG. 11  is a perspective view of a plurality of press-fit pins welded according to the invention to a carrier strip, 
           [0018]      FIG. 12  is a perspective view of a press-fit pin provided according to the invention with welded-on shoulders, and 
           [0019]      FIG. 13  is a perspective view of press-fit pin shot through according to the invention by a pin. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0020]    The construction of a press-fit pin configured according to the invention will firstly be described with reference to  FIG. 1  which shows a perspective view of the compressed press-fit pin  1 . The compressed press-fit pin  1  has at least one compressed location  2  in the longitudinal direction. In the region of the compressed location  2  the press-fit pin  1  has a cross-sectional area Q′ that is widened compared with its original cross-sectional area Q. A step forms at the transition from the cross-sectional area Q to the widened cross-sectional area Q′. The step forms a plane of which the normal runs in the longitudinal direction L of the press-fit pin  1 . The step thus constitutes a shoulder element  3 . 
         [0021]    A shoulder element  3  is hereinafter taken to mean any kind of edge, corner, nose  4 , projection  15 , step, bend  12  or kink on which a tool can be supported to exert a force on the press-fit pin  1  in the longitudinal direction L. The spacing of shoulder element  3  to the tips  23  of the press-fit pin  1  should be large enough that the tips  23  are not damaged when the pin  1  is processed. This condition results in a middle section on the press-fit pin  1  which is suitable for attachment of the shoulder elements  3 . 
         [0022]    The position, shape and number of shoulder elements  3  can be freely selected in this middle section to attain optional manageability of the press-fit pin  1  for the respective application. 
         [0023]    The shoulder elements  3  can improve manageability as required in that, in addition to supporting a tool, they can also be used as holding members  21  as shown in  FIG. 12 , a stop, a fixing, a measuring or positioning aid. 
         [0024]      FIG. 2  shows a press-fit pin  1  constructed according to the invention comprising an impression  6  and a lateral nose  4 . The underside of the nose  4  has a shoulder element  3 . A bevel  5  which tapers toward the press-fit pin  1  sits on the upper side of the nose  4 . The material of the press-fit pin  1  required for forming the nose  4  is pressed outwards from the center of the press-fit pin  1  by the impression  6 . 
         [0025]      FIG. 3  shows a plurality of press-fit pins  1  provided with a gap  7  and which are framed by a carrier member  10 . The gap  7  can be introduced in the center of the press-fit pin  1 , in which gap  7  the pin  1  is for example inserted and widened from the inside. The external contour of the press-fit pin  1  locally increases in the region of the gap  7  and shoulder elements  3  are produced. Fingers  8  that partially surround the press-fit pin  1  are locked to the shoulder element  3  in the longitudinal direction L. The fingers  8  that at least partially surround the press-fit pin  1  are joined together by the connection  9 . A plurality of fingers  8  that surround the press-fit pins  1  are joined to each other by bridges  11  and mounted side by side form a continuous carrier member  10 . 
         [0026]      FIG. 4  shows a press-fit pin  1  constructed according to the invention and on which a plurality of noses  4  are provided. The side-by-side mounting of a plurality of noses  4  laterally on the press-fit pin  1  member the pin  1  can be pressed in a printed circuit board or female connector. The noses  4  act as barbs in this case. The bevels  5  on the noses  4  allow the noses  4  to penetrate the relevant component and the shoulder elements  3  on the noses  4  prevent the press-fit pin  1  from sliding out of the component. At the same time the shoulder elements  3  are used to secure the press-fit pin  1  in a tool which presses the press-fit pin  1  into the component. 
         [0027]      FIG. 5  shows a plurality of press-fit pins  1  which have a bend  12  and are framed in a carrier member  10 . The bend  12  produces shoulder elements  3  on the press-fit pins  1 . The carrier member  10  can be supported on the shoulder elements  3 . The force transmission from carrier member to press-fit pin  1  in the longitudinal direction L is improved thereby. 
         [0028]      FIG. 6  shows a press-fit pin  1  which has an S-shaped bend  12  in the center. There is a plurality of shoulder elements  3  along the S-shaped bend  12 . The shoulder elements  3  can be used to support a tool to press the press-fit pin  1  into a component and as a stop when pressing the press-fit pin  1  into a component. 
         [0029]      FIG. 7  shows a press-fit pin  1  that is notched on its longitudinal edges  17  and is framed by a ring  14 . On its inner side the ring  14  has projections  15  which engage in the notches  13  in the press-fit pin  1 . Engagement of the projections  15  in the notches  13  results in interlocking fit between ring  14  and press-fit pin  1 . The interlocking fit ensures a secure seat of the ring  14  on the press-fit pin  1 . An integral connection can be achieved between the ring  14  and the press-fit pin  1  by constructing the projections  15  as welds. 
         [0030]      FIG. 8  shows two press-fit pins  1  provided at certain sections of their longitudinal edges  17  with bevels  16  and which are framed by a carrier member  10 . The framing of the press-fit pins  1  in the carrier member  10  takes place by member of the fingers  8  that surround the press-fit pins  1 . The fingers  8  that surround a press-fit pin  1  have a connection  9 . The surrounding fingers  8  form a unit with the connection  9 . 
         [0031]    In the step of the bevels  16  the press-fit pins  1  have shoulder elements  3 . The fingers  8  that surround the press-fit pins  1  are supported on the shoulder elements  3 . There is an interlocking fit between the surrounding fingers  8  and the press-fit pin  1  because of the support of the surrounding fingers  8  on the shoulder elements  3  on the press-fit pin  1 . 
         [0032]    When processing the press-fit pin  1  the surrounding fingers  8  can be used as holding members. When used as holding members they facilitate handling of the press-fit pins  1 . The surrounding fingers  8  also comprise shoulder elements  3 ′ which promote an introduction of force in the longitudinal direction L of the press-fit pin  1 . 
         [0033]    The surrounding fingers  8  of a plurality of press-fit pins  1  can be joined together by the bridges  11 . In their entirety, the surrounding fingers  8  thus produce a carrier member  10 . The carrier member  10  has holes  18  between the bridges  11 . The holes  18  simplify the mechanical feed of a plurality of press-fit pins  1  to a tool. 
         [0034]      FIG. 9  shows two press-fit pins  1  which penetrate a flat body  19 . The flat body  19  is supported in the longitudinal direction L on the shoulder elements  3 ′ of the noses  4  formed on the press-fit pins  1 . The flat body  19  can also act as a carrier member and press-in shoulder and be constructed as a disc, plate or profiled body. The flat body  19  can be attached to the press-fit pin with integral, interlocking or non-positive fit and by a combination of several joining methods by being welded, pressed or adhered for example to the press-fit pin  1 . 
         [0035]      FIG. 10  shows two press-fit pins  1  which are enclosed by two flat bodies  19 ′. The flat bodes  19 ′ are joined together at the weld points  20 . The flat bodies  19 ′ are supported on the noses  4  in the longitudinal direction L of the press-fit pins  1 . The noses  4  are formed on the press-fit pins  1 . The flat bodies  19 ′ are locked on one side in the longitudinal direction L of the press-fit pins  1  by the noses  4 . 
         [0036]    The flat bodies  19 ′ can be used as a holding member and carrier member and facilitate pressing of the press-fit pins  1  into a component in the longitudinal direction L. The one-sided locking member that the flat bodies  19 ′ can be removed from the press-fit pins  1  counter to the longitudinal direction L. 
         [0037]      FIG. 11  shows three press-fit pins  1  to which a carrier member  10  is welded. The carrier member  10  comprises fingers  8  that surround the press-fit pins  1 . The surrounding fingers  8  are integrally connected to the press-fit pins  1  at the weld points  20 . 
         [0038]    The surrounding fingers  8  and the shoulder elements  3 ′ on the carrier member  10  can be used by a tool for introducing a force in the longitudinal direction L or satisfy the purpose of a holding member. 
         [0039]    The carrier member  10  is used to feed a plurality of press-fit pins  1  into a processing machine. The carrier member  10  can be removed before, during or after processing of the press-fit pins  1 . 
         [0040]      FIG. 12  shows a press-fit pin  1  with welded-on holding member  21 . The holding member  21  comprise shoulder elements  3 ′. By way of the shoulder elements  3 ′ the holding member  21  may be used as press-in shoulders for pressing the press-fit pin  1  into a component. Since the holding member  21  comprise shoulder elements  3 ′ on both sides, they can be used for introducing a force in the longitudinal direction L of the press-fit pin  1  and as a stop. 
         [0041]      FIG. 13  shows a press-fit pin  1  which is shot through by a pin  22 . Since the pin  22  is longer than the press-fit pin  1  is wide, the pin  22  can be used as a press-in shoulder. The pin  22  is used to transmit a force to the press-fit pin  1  in the longitudinal direction L thereof or to secure the pin. 
         [0042]    Pressing a press-fit pin  1  into a component is also facilitated if it comprises tips  23  at its ends. 
         [0043]    Deviations from the above-described embodiments are possible within the inventive idea. Thus shoulder elements  3  or  3 ′, noses  4 , impressions  6 , gaps  7 , bends  12 , notches  13 , projections  15  and bevels  16  used as assembly aids can be provided on the press-fit pin  1  where assembly of the pin requires. A pin  1  can therefore be pressed deeper into a component the closer such an assembly aid is located to an end of the pin  1 . If an assembly aid is positioned centrally on the pin  1  in such a way that pin and assembly aid are symmetrical, the pin can be pressed into a component with any end. The positions of the surrounding fingers  8 , carrier strips  10 , flat bodies  19  or  19 ′, holding member  21  and pins  22  can also be varied as desired. 
         [0044]    To provide press-fit pin material for forming shoulder elements  3  and noses  4  the press-fit pin  1  can be compressed or impressed as desired. 
         [0045]    All noses  4 , impressions  6 , gaps  7 , surrounding fingers  8 , carrier strips  10 , bends  12 , notches  13 , rings  14 , projections  15 , bevels  16 , flat bodies  19 , holding member  21  and pins  22  comprising shoulder elements  3  or  3 ′ can be used as press-in shoulders and serve as holding members. 
         [0046]    The shoulder elements  3  or  3 ′ can also be used as stops when processing the press-fit pin  1 . 
         [0047]    Surrounding fingers  8 , carrier strips  10 , flat bodies  19  and pins  22  can be removed or remain in place following processing of the press-fit pin  1 .