Electrical connector

Abstract: Connector having at least one contact element. The connector is provided with a housing having an opening for each conductor to be introduced and removed in which opening the contact element is arranged. The contact element is provided with a spring-loaded and pivotable wall having an opening with an edge for engaging the conductor. The wall is arranged such that when the conductor is introduced it can be pivoted in a direction of freeing the opening and if the conductor moves outwardly it can exert a clamping force thereon against the wall of the housing. The contact element is rigidly connected to the housing at the base of the housing.

Description: The invention relates to a connector according to the preamble of claim 1. Such a connector is known from DE-A-33 11 709. Connectors having a contact element with a pivotable wall wherein the pivot point of the wall is positioned in the direction of introduction of the conductor beyond the point of contact of the conductor and wall are used in applications wherein it is necessary to restrict a clamping force of the pivotable wall to the conductor. This means that if a too large force is exerted on the conductor it will slip through the opening. Such a provision is important to prevent damage to the connector or if this connector is soldered to a printing circuit board damage to the circuit. To be able to release the conductors from the contact element the housing according to the DE-A-3 311 709 can be moved along a limited path relative to the contact elements. By pushing the housing relative to the contact element the opening in the pivotable wall will be enlarged to release the conductor. Because of this the contact elements have to provide the support face between the conductor and a further electric member, such as a board of a printing circuit. To increase the support face each contact element is U-shaped near the contact point with the board. Because of the possibility of the movement of the housing relative to the contact elements it is necessary to take further steps to guarantee contact between the conductor and the contact element. This is realized in that a set of separate contact lips is provided on the contact element between which the conductor has to be engaged. Because of this the contact element is further complicated. If this known connector comprises several contact elements problems can occur during introduction of a conductor. Because the housing can tilt relative to the contact elements the openings in the housing might not align with the opening in the contact elements. Furthermore high local pressure on the conductor will be directly transferred to the nearest contact element and give stress concentration on the printed circuit board below. During introduction of the connector with several contact elements in the printed circuit board problems can arise because there is no guarantee that the contact elements will all penetrate sufficiently in the printed circuit board during soldering. The same applies if instead of soldering a further connector is coupled to this connector. Because of the complicated shape of the connector it is not possible to produce the housing in one single step. It is always necessary to assembly the housing from at least two several parts. The invention aims to obviate these drawbacks and to provide an improved connector. According to the invention this is realized with a connector according to claim 1. Because the contact strip is connected to the housing at the base of the housing during introduction of the connector in a printed circuit board or other connector it is guaranteed that the contact elements all penetrate in the same extent in the other member. If on the housing a localized force is exerted, this force will equally be distributed to the base of the housing, which can have a considerable area, such that the underlying printed circuit board or other connector is saved. Tilting of the housing during introduction of a multi conductor wire is not longer possible. Because of the fixed relationship of the lower part of the contact element to the housing its upper part comprising the pivotable wall can provide, in corporation with the wall of the housing, sufficient engagement with the conductor to obviate further contact lips to engage the conductor. From FR-A-2,566,967 a connector is known wherein the contact element is rigidly connected to the base of the housing. However, this contact element does not cooperate with the housing to provide contact with a conductor to be introduced. The contact element according to the French specification is a complicated part comprising several tongues moving relative to each other. If the contact element according to the French specification would be used without connection to the housing and e.g. directly soldered to a printed cicuit board the problems as with the device according to DE-A-3 311 709 would not arise. The drawback of the device according to the French specification is that it is very complicated, uses a lot of material and the pivot point of the pivotable wall is in the direction of movement of the conductor before the point of engagement of the conductor with the pivotable wall. This means that no restriction exists in the acting against drawing to the conductor back. This means that if this pull back force is too considerable damage will occur. According to an embodiment of the invention the contact element comprises a single strip of conducting material of which one extremity provides the pivotable wall and the other extremity provides a connecting pin and being provided with means to engage the housing. Because of the simple structure of the contact element it is possible to provide the housing as one part for example by injection moulding. In the housing no means are provided to move the pivotable wall in such a direction that the conductor can be pulled back. This can be realized with means for moving it aside the at least one spring loaded and pivotable wall in the wall of freeing the opening for a conductor. These means can be either separated means which can be used for several connectors or cap means constructed to be fitted over the housing of the connector from the at least one opening for receiving the conductor and having at least one corresponding opening and at least one device for displacing the at least one spring loaded and pivotable point. According to a further embodiment of the invention the opening is a cut-out in the pivotable wall part. In this way the use of material for the pivotable wall can be limited as much as possible. To equally distribute the forces acting on the several contact elements provided in a connector this can be disposed in a staggered arrangement. Because of this more contact elements can be arranged on the same area. The invention will be explained in more detail below with reference to the exemplary embodiments shown in the drawing. In this: Figure 1 shows diagrammatically in side elevation a connector according to the invention, Figure 2 shows a section along the line II-II in Figure 1, Figure 3 shows the connector according to Figure 1 provided with unlocking means diagrammatically in side elevation, and Figure 4 shows a section along the line IV-IV in Figure 3. Figure 1 shows a connector indicated in its entirety by 1. This comprises a connector housing 2 for receiving a row 4 of conductors 3. The connector housing 2 is provided with contact ends 5 to be fitted in openings 6 of an only partially shown printed circuit board 7. As is clear from this figure contact ends are placed in two opposed rows in a staggered arrangement. This allows further miniaturization. Figure 2 shows the connector housing 2 according to the invention in section. In this, a conductor 3 is fitted in the opening intended therefor. A channel for receiving the conductor 3 comprises a fixed wall 8 and a spring-loaded and pivotable wall 9. The spring-loaded and pivotable wall 9 comprises, in the exemplary embodiment shown here, the extension of the contact end 5 and is provided with an opening 12 or a cutout suitable for the same purpose. Edge 10 of said opening 12 or cutout acts on the conductor 3. In Figure 2 it is shown that near contact end 5 contact element 25 is provided with recess 26 to engage a protrusion 27 in the base of housing 8. The device acts as follows: when the conductor 3 is inserted, the wall 9 moves outwards in the direction of the arrow 11, with the result that the conductor 3 is able to move along the edge 10 through the opening 12 or cutout and arrives in the position shown in Figure 2. As a result of the spring-loaded action of the spring-loaded and pivotable wall 9 in the direction of arrow 13, the edge 10 is clamped against the conductor 3. If a force is exerted on the conductor 3 in the direction of outward movement of said conductor, the edge 10 will clamp into the material of the conductor 3. It is evident that the pivoting point of the wall 9 is situated near the receiving part 14 of the contact end 5. This is in contrast to the prior art, in which the pivoting point is situated precisely at the other end of the spring-loaded and pivotable wall 9, i.e. at the end where the conductor 3 is introduced into the connector. In the device according to the prior art, this has the result that when a tensile force is exerted on the conductor 3, the clamping force on the spring-loaded and pivotable wall 9 becomes increasingly larger with the risk of damage to, for example, the printed circuit board 7. Because the pivoting point of the spring-loaded and pivotable wall 9 is situated, in the present invention, at the other side of the conductor near the receiving part 14, the clamping force exerted by the edge 10 will have certain limits. These limits are determined in particular, by the frictional force between the different parts and the angle at which the wall 9 acts with its edge 10 on the conductor 3. Figure 3 shows the connector 1 according to Figures 1 and 2 which is provided with unlocking means 15 such as a cap to be fitted over the connector housing 2 and having corresponding openings for introducing conductors 3. The operation of this unlocking means 15 is evident from Figure 4, a section along the line IV-IV in Figure 3. den the unlocking means 15 are pressed in, lug 16 acts in the direction of arrow 17 on the end 18 of the spring-loaded and pivotable wall 9 and this is moved outwards in the direction of the arrow 11. Subsequently, the conductor 3 can be introduced unhindered into the channel intended therefor. After the force on the unlocking means 15 is removed, the latter move back upwards, with the result that the conductor 3 is clamped by the movement of the spring-loaded and pivotable wall 9 in the direction of the arrow 13. In order to prevent the un- locking means 15 becoming detached from the connector housing 2, the receiving part 14 of the housing 2 and an end part 20 of the unlocking means 15 are provided with snap means 21 which engage in each other. The use of the unlocking means 15 is of importance if it is intended to remove the row 4 of conductors 3 after introduction and if the conductors 3 are composed of a less rigid material, with the result that they are unable to bend the spring-loaded and pivotable wall 9 aside independently.

Claims: Connector for the clamping connection of an electrical conductor (3) comprising at least one contact element (25) of electrically conducting material having a pivotable wall part (9) and contact end (5) and a housing (2) in which the contact element is received, the housing having at least an opening for introducing and removing the conductor, and a fixed wall (8), wherein the pivotable wall part (9) is springloaded, the pivotable wall part (9) having an opening (12) with two opposed edges, the opening (12) and fixed wall (8) being positioned such relative to each other as to define a passage for the conductor, wherein the fixed wall (8) is near the opening of the housing and cooperates with one edge (10) of the opening (12) remote from the pivot point of the pivotable wall part (9) and wherein the pivot point is near the contact end receiving part (14) of the housing (2), characterized in that , the contact element (25) is a single strip of material consisting of two portions of which one portion provides the pivotable wall part (9) and the other portion the contact end (5) comprising a connecting pin, said contact element (25) being rigidly connected to the basis of the housing. Connector according to Claim 1 characterized in that the opening (12) is a cutout in the pivotable wall part (9). Connector according to one of the preceding claims, characterized in that it is provided with means (15) for moving aside the spring-loaded and pivotable wall part (9) in the direction of freeing the opening for a conductor. Connector according to Claim 3, wherein said means (15) are constructed from a cap to be fitted over the housing of the connector for the at least one opening for receiving the conductor and having at least one corresponding opening and at least one device for displacing the spingloaded and pivotable wall of the at least one contact. Connector according to claim 1 comprising several contact elements (25) which are disposed in a staggering arrangement.

Inventors: SCHALK PETRUS WOUTER HENDRICUS, SCHALK, PETRUS WOUTER HENDRICUS
Applicants: CONNECTOR SYSTEMS TECH NV, DU PONT NEDERLAND, CONNECTOR SYSTEMS TECHNOLOGY N.V., DU PONT DE NEMOURS (NEDERLAND) B.V.
Application year: 1990
Main classification: H01R4
IPC codes: H01R12, H01R4