GB2050078A

GB2050078A - A plug connector

Info

Publication number: GB2050078A
Application number: GB8011314A
Authority: GB
Original assignee: Burndy Corp
Current assignee: FCI USA LLC
Priority date: 1979-04-05
Filing date: 1980-04-03
Publication date: 1980-12-31
Also published as: DE3013202A1; AU544445B2; ES257552Y; GB2050078B; AU5714880A; FR2453510B1; ES257552U; FR2453510A1; DE3013202C2

Abstract

A plug connector suitable for a printed circuit board has contact elements arranged in pairs with projecting pins 14 in a common plane P. To achieve this configuration, the contact elements are identical, and each has a contact spring 12 projecting from a flat side portion 11, to the opposite side of which the pin 14 is secured. One contact element of each pair is turned through 180 DEG relative to the other, to place the pins in the plane 14. <IMAGE>

Description

SPECIFICATION Plug connectors This invention relates to plug connectors such as for example those which are used in racks for pluggable printed circuit boards.

In the accompanying drawings, Figure 1A is a plan view of the underside of a known plug connector; Figure 1B is a plan view of a underside of a plug connector in accordance with the invention; Figure 2 is a perspective view of a pair of contact elements of a plug connector shown in Fig. 1 B placed adjacent to one another; Figure 3 is part of a front view of a plug body of a connector shown in Fig. 1 B and having contact elements fixed therein; Figure 4 is a cross-section on the line IV-IV of Fig. 3; and Figure 5 is a partly cut-away perspective view of a plug body with contact elements in accordance with the invention.

Known plug connectors for printed circuit boards essentially consist of a plug body of insulating material provided with grooves and openings in which contact elements are mounted at regular intervals from one another. Said contact elements contain contact springs which are the lower side thereof are extended up to the outside of the plug body with connecting or welding pins for connection with an electrical wiring.

!n these plug connectors (such as for example HE7, according to French norms and some according to DIN, etc) said connecting pins extend in the same transverse plane as the contact springs. In order to achieve the greatest possible distance between said pins, said contact elements are alternately turned through 180 with respect to one another. In this way, the pins project from the underside of the plug connector in the staggered configuration shown in Fig. 1A of the drawings, each pin being spaced from the next by a distance L measured longitudinally of the connector.

This staggered arrangement of the connecting pins is a disadvantage owing to the fact that the available space between the pins is too small for the wrapping machines which connect the electric conductors with the pins by a technique known as "automatic wire wrapping".

The present invention has for its object the avoidance of the drawback, and this is achieved by the fact that a straight connecting pin is fixed to a straight portion of each Ushaped contact base in such a way that when the contact elements are mounted by pairs in the plug body, the respective connecting pins of each pair lie in a common plane which is parallel to the plane of the contact springs. In this way, an arrangement is obtained as illustrated in Fig. 1 B in which the pins 14 of each pair of connectors are opposite to each other in a transverse plane P situated centrally with respect to two adjacent contact springs 1 2.

A preferred form of contact element and plug body will now be described with reference to the remaining Figures of the accompanying drawings.

As shown in Fig. 2, each contact element 10 consists of a U-shaped contact spring carrier provided with a flat portion 11 and two spring legs 1 2 each bent towards the other to form the proper spring contact planes. At the underside of the flat portion 11, there is provided a flat strip 1 3 which extends sideways and downwards and has fixed to it, on the side opposite to the contact springs 12, a straight connecting pin 1 4.

The connecting pin may be fixed in place by spot or butt welding, but other fixation means may be used. The connecting pin 14 has a square cross-section to facilitate automatic wire wrapping and for the same reason, its free end is cut to form an obtuse point 1 5.

At a short distance under the portion of the pin 14 which is fixed to the strip 1 3 of the contact spring carrier 11, the connecting pin is provided with angular deformations 1 6 on its lateral edges to fix the pin rigidly in the plug body.

In a centrally located plane of the contact spring carrier there is a longitudinal indentation 1 7 for reinforcing mechanically the contact spring carrier.

The plug body can take various other configurations depending upon the use for which it is intended.

In each case, the contact elements are assembled in groups of two, each turned through 180 with respect to the other, in such a way that the connecting pins of each pair lie in one and same transverse plane P (Fig. 1 B) while their respective contact springs are spaced longitudinally by the desired distance L. The transverse plane P is located centrally with respect to the contact springs at a distance L/2 therefrom.

Figs 3 and 4 show an example of a plug body with the contact elements 10 fixed therein.

The plug body 20 is made in one piece and includes two longitudinal side walls 21 and a base portion 22. The side-walls 21 form a central opening 23 and are provided at regular intervals on their inner side with protecting or reinforcing ribs 24. The base portion 22 is provided with a set of holes 25, the crosssection of which corresponds to the crosssection of the connecting pins 1 4. The protecting or reinforcing ribs 24 divide the plug body 20 in its longitudinal direction in compartments 26 (Fig. 5), in each of which is fixed a pair of contact elements 10 turned through 180D with respect to each other as shown in Fig. 2.The flat portions 11 of the contact spring carrier of such a pair of contact elements are separated from one another by a vertical supporting rib 27 which is part of the base portion 22 and which is located centrally in each compartment 26.

Two opposite reinforcing ribs 24 which also extend up to the base portion 22 are connected to one another at about the same level as the supporting ribs 27 by means of ribs 28 which separate the compartments 26 from one another at the bottom thereof. These provisions ensure a correct placing and an effective protection against mechanical deformations during coupling of the connector plug. Both adjacent contacts are thus maintained safely at distance from one another and are electrically insulated. At a small distance above said ribs 28 each reinforcing rib 24 is provided with a broadened portion 29 which causes pretensioning of the contact springs 1 2 so as to ensure that the contact springs remain aligned accurately throughout the whole length of the plug body.

The contact elements 10 remain firmly fixed in place after their fixation in the plug body 20 by means of the lateral deformations 1 6 of the connecting pins 1 4. These deformations 1 6 cause the pins 14 to be jammed in such a way in the holes 25 of the body 20 that the force which is necessary to withdraw them is maintained within the norms or limits specified for automatic wire wrapping.

This way of fixation also permits accurate adjustment of the depth occupied by the contact elements 10 in the body 20 upon mounting. Thus for example, alternate pairs of contact elements 10 can extend to different depths. This may be necessary inter alia in order to reduce the total penetrating force of the connector plug or to provide an advanced contact in order to obtain a so called "first make-last break" contact. An important advantage of the arrangement described above is that the contact elements are positioned, maintained and protected in such a way that it is possible to replace an individual contact element from the front side without danger of damaging or distorting the other contacts. The replacement of a contact element necessitates the use of an auxiliary equipment or facility.

Another advantage is that by fixing a straight connecting pin on a flat and undeformed portion of the contact spring carrier, the problems of tolerance are reduced to a minimum.

Claims

1. A plug connector, for example for printed circuit boards, consisting of a plug body having contact elements fixed therein, each of said contact elements consisting of at least one pair of contact springs, a U-shaped contact spring base which connects said springs to one another and which carried said springs, and a connecting pin which extends from said contact spring base up to the outside of the plug body, the pin being fixed to the contact spring base in such a way that when the contact elements are mounted by pairs in the plug body, the respective connecting pins of each pair lie in a common plane which is parallel to the plane of the contact springs.

2. A plug connector according to claim 1, characterized in that the U-shaped contact spring base of each contact element comprises a flat portion on the back side of which a straight connecting pin is fixed.

3. A plug connector according to claim 2, characterized in that the connecting pin of each contact element is fixed on a strip which extends sideways in downwards direction starting from the flat portion of the contact spring base.

4. A plug connector according to claim 3, characterized in that the connector pin is provided at a short distance below its portion which is fixed to the strip of the contact strip with angular deformations to obtain a solid fixation in the plug body.

5. A plug connector according to any of claims 2 to 4, characterized in that the flat portion of the contact spring is provided with an elongate indentation in order to strengthen mechanically the contact spring carrier.

6. A plug connector according to any preceding claim, characterized in that the plug body is made in one piece and consists of longitudinally extending side-walls which are connected with one another by means of a base portion and which form a central opening, the side-walls being provided at regular intervals on their inner side with protecting or reinforcing ribs.

7. -A plug connector according to claim 6, characterized in that the protecting or reinforcing ribs divide the plug body longitudinally in small compartments each of which contains a pair of contact elements fixed therein, each of said contact elements being turned through 180 with respect to the other adjacent contact element.

8. A plug connector according to claim 7, characterized in that the flat portions of the pair of contact elements contained in one compartment are separated from one another and supported by means of a vertical supporting rib which is part of the base portion of the plug body and which is located centrally of each said small compartment.

9. A plug connector according to any of claims 6 to 8, characterized in that the reinforcing ribs which extend up to the base portion of the plug body are provided with a broadened portion which ensures that the contact springs after fixing receive a given amount of pre-tension.

10. A plug connector substantially as hereinbefore described with reference to the drawings, with the exception of Figs. 1A.

11. A plug contact element as defined in claim 1 and substantially as illustrated in Fig.

2 of the accompanying drawings.