EP0545790B1 - Electrical interconnection device - Google Patents

Abstract

The electrical interconnection device comprises a body (1) made of an insulating elastic material through which passes at least one conduit (2), and at least one conducting element (23) inserted into the conduit (2) in order to establish therein an electrical contact with another conducting element (23). A bearing shoulder (26) formed between a shank (24) and a head (25) of the conducting element (23) is applied against the body (1) in the vicinity of the conduit (2), and prevents the complete penetration of the conducting element (23) into the conduit (2). Use in particular in connectors or in electronic assemblies. <IMAGE>

Description

The present invention relates to an electrical interconnection device as described, for example, in document EP-A-0 431 566.

This type of device is intended to make contacts between different components or electrical conductors. It can for example be part of an electronic assembly or be integrated in a connector.

These devices usually include a rigid insulating support in which are mounted conductive elements making the desired contact. We are looking for two properties to guarantee contact safety: pressure and support. The pressure is linked to the support force between the contact surfaces, and the support is the ability of the contact to be maintained during a certain displacement of the conductive elements.

To obtain these two properties, the conductive elements of the device are generally mounted with elasticity with respect to the rigid insulating support. A first possibility consists in interposing elastic members, such as springs, between the conductive elements and the support. These elastic members increase the number of parts and therefore the cost of the device. They can also pose mounting problems when the device is small and large. Another possibility is to give elastic properties to the conductive elements themselves. However, these elastic properties are difficult to achieve reliably when the conductive elements are small. In addition, these elastic properties degrade after several connections and disconnections of the components.

The object of the present invention is to eliminate the above drawbacks and to simplify the structure of known interconnection devices.

The invention thus provides an electrical interconnection device, characterized in that it comprises a body of insulating elastic material traversed by at least one conduit, and at least one conductive element introduced into the conduit to establish electrical contact therewith. other conductive element, and in that support means applied against the body in the vicinity of the conduit, prevent the complete penetration of the conductive elements in the conduit.

Thus, the elastic maintenance of the contact between the conductive elements is provided by the insulating body of the device. If the components electrically interconnected by the device move slightly, the support means elastically deform the body in the vicinity of the duct, which increases the contact pressure. The part of the conductive element situated outside the duct may have a shape adapted to that of the components to be interconnected, for example a curved shape, if it is intended to bear against conductive pads of a printed or integrated circuit.

In a preferred version of the device according to the invention, the conductive element or elements introduced into the conduit elastically deform the conduit, preferably the cross section of the conduit.

This arrangement allows the conductive elements to be held in the body after assembly of the device and before associating the device with components to be interconnected.

Other features and advantages of the present invention will appear in the detailed description below of exemplary embodiments, read in conjunction with the appended drawings, in which:

Figure 1 is an exploded view of a device according to the invention.

Figure 2 is a sectional view of the device of Figure 1 after assembly.

Figure 3 is a sectional view of the device of Figures 1 and 2 in operation.

Figures 4 and 5 are sectional views similar to those of Figures 2 and 3 of a second embodiment of the invention.

FIG. 6 is a sectional view of the conductive elements of the embodiment of FIGS. 4 and 5, taken along the plane VI-VI indicated in FIG. 5.

Figures 7 to 9 are sectional views similar to those of Figures 4 to 6 of a third embodiment of the invention, the view of Figure 9 being taken along the plane IX-IX indicated in Figure 8.

Figures 10 to 12 are views similar to those of Figures 1 to 3 of a fourth embodiment of the invention.

Figures 13 to 15 are figures similar to those of Figures 4 to 6 of a fifth embodiment of the invention, the view of Figure 15 being taken according to plan XV-XV shown in Figure 14.

FIG. 16 is a plan view of an alternative conductive element usable in the device according to the invention.

Figures 17 and 18 show a variant of the embodiment shown in Figures 2 and 3.

Referring to Figure 1, a device according to the invention comprises a body 1 of insulating elastic material. The body 1 may for example be a plate of silicone-based elastomer material, having a thickness of the order of a few millimeters. The body 1 is crossed by one or more rectilinear conduits 2, for example having a circular section.

The device shown in Figures 1 to 3 comprises two conductive elements 3 of metal, which are introduced into the duct 2 by two opposite faces of the body 1. In the example shown, the two conductive elements 3 have an identical structure. They each comprise a rod 4 penetrating into the conduit 2 and a domed head 5 remaining outside the conduit. A shoulder 6 is formed between the rod 4 and the head 5. When the conductive elements 3 are introduced into the duct 2, the shoulders 6 come to bear against the surface 7 of the body 1 in the vicinity of the duct 2.

The rod 4 of each conductive element comprises, at its end opposite to the head 5, a contact surface 8 inclined with respect to the direction of the rod 4. When the conductive elements 3 are introduced into the conduit 2, their contact surfaces respective 8 are parallel to each other and form an angle A with the plane P perpendicular to the direction D of the conduit 2 (Figure 2). Thus, when the conductive elements 3 introduced into the conduit are pushed axially towards one another, they tend to slide along their respective contact surfaces 8 while maintaining contact between these two surfaces.

As shown in Figure 1, the rod 4 of each conductive element 3 has a cross section greater than that of the conduit 2 when the conductive elements 3 are not introduced there. Thus, the presence of the conductive elements 3 in the conduit 2 widens the conduit 2, which keeps the conductive elements 3 in place after the assembly of the device (FIG. 2).

In Figures 2 and 3, the components 10 are shown interconnected by means of the device. In the example shown, the components 10 are interconnected by means of contact pads 11, deposited on their surface. The components 10 can for example be integrated or printed circuits. In the operating position shown in Figure 3, the contact pads 11 are applied against the domed heads 5 of the conductive elements 3 with an axial pressure. This axial pressure elastically deforms the body 1 by means of the support shoulders 6 of the conductive elements 3. The two conductors are offset one with respect to the other. This further distorts the conduit. The tendency of the conduit to return to its rest form ensures the contact pressure between the contact surfaces 8. The accompanying property of the contacts results from the inclination of the contact surfaces 8 relative to the plane P transverse to the direction D of duct 2. If components 10 move slightly in the axial direction, the conductive elements 3 slide relative to each other along their respective contact surfaces 8 while maintaining the electrical contact.

The contact pressure can be adjusted to a certain extent by adapting the spacing of the two components 10 to be interconnected, or, in the case where this spacing is imposed, by adapting the thickness of the elastic body 1 and the length of the conductive elements 3 The contact pressure can also be varied by modifying the modulus of elasticity of the material of the body 1.

The embodiment illustrated in FIGS. 4 to 6 differs from that illustrated in FIGS. 1 to 3 by the shape of the conductive elements 23. These also include a rod 24, a domed head 25, and a bearing shoulder 26 formed between the rod 24 and the head 25. In cross section (FIG. 6), each rod 24 has the shape of a semicircle delimited by a diametrical line d extending along the contact surfaces 28, which are planar. When combined, the rods 24 form, in cross section, a circle with a diameter greater than that of the conduit 2. Thus, when the two conductive elements 23 are introduced into the conduit 2, these widen the conduit 2 as shown in Figure 4. Thus, the radial elastic clamping of the conduit on the conductive elements 23 ensures the contact pressure between the contact surfaces 28. The accompanying condition is fulfilled because this pressure is maintained when the surfaces 28 slide the one on the other axially. To facilitate mutual docking of the conductive elements 23 during their introduction into the duct 2, they can be given bevelled ends 29, as indicated in dashes in Figure 4.

The contact surfaces 28 of the conductive elements 23 are parallel to the direction D of the duct 2, that is to say that they form a right angle with respect to the plane P perpendicular to the direction D, which guarantees good support of the contact.

FIGS. 7 to 9 illustrate another embodiment of the invention usable when one of the components to be connected 50 is a pin component 51. In FIGS. 7 to 9, two pins 51 of cylindrical shape, projecting perpendicularly to a surface 56 of the component 50. The device comprises a body 1 similar to that described for the previous exemplary embodiments, and, for each pin 51, a conductive element 43 of metal. The body 1 comprises rectilinear conduits 2, the cross section of which is close to that of the pins 51 and the spacings of which correspond to those of the pins 51.

The conductive elements 43 comprise a rod 44, a head 45, and a support shoulder 46 formed between the rod 44 and the head 45. The rod 44 has the shape of a half cylinder whose internal diameter corresponds to that of a pin 51, and whose outside diameter is slightly greater than that of the conduit 2. The contact surface 58 of the conductive pin 51 is defined by one side of the cylindrical shape of the pin 51. The contact surface 48 of the conductive element 43 has a concave shape matching the convex shape of the contact surface 58 of the spindle 51. The contact surface 48 is defined inside the rod 44 by generatrices parallel to the direction D of the conduit 2.

To assemble the device illustrated in Figures 7 to 9, the conductive elements 43 are first introduced into the corresponding conduits 2, then the conductive pins 51 of the component 50 are introduced via the opposite face of the body 1 so that the ends of the pins 51 come into contact with the interior rods 44 (Figure 7). Then, when the pin component 50 and the component with conductive pads 10 are urged towards each other, the pins 51 slide along the rods 44 of the conductive elements 43. The contact surfaces 48, 58 are held in place. one against the other by the elastic force generated by the deformation of the body 1 resulting on the one hand from the support of the shoulders 46 on the surface 7 of the body 1 in the vicinity of the conduits 2, and on the other hand from the support of the surface 56 of the component 50 on the opposite surface 7 of the body 1.

In the embodiment of the invention illustrated in FIGS. 10 to 12, the body 61 of insulating elastic material is traversed by a conduit 62 consisting of two rectilinear parts 62a, 62b forming between them an angle which, in the example shown, is equal to 90 °. The rectilinear parts 62a, 62b of the conduit 62 lead to two adjacent surfaces 67a, 67b of the body 61.

In each rectilinear part 62a, 62b of the conduit is introduced a conductive element 63 having the same structure as the conductive element 3 of the embodiment illustrated in Figures 1 to 3. The rod of the conductive element 63 has a slightly larger diameter to that of the corresponding duct part. The contact surface 68 of a conductive element 63 forms an angle of approximately 45 ° with the plane Pa, Pb, perpendicular to the direction Da, Db of the corresponding part of the conduit 62a, 62b. So the contact surfaces 68 of two conductive elements 63 are practically parallel to one another when the device is assembled (FIG. 11). The electrical contact between the conductive elements 63 is established by the contact surfaces 68 at the intersection between the two rectilinear parts 62a, 62b of the conduit 62.

The device illustrated in Figures 10 to 12 is used to interconnect components 10 whose conductive pads 11 are located in planes perpendicular to each other. To apply the heads of the conductive elements against the contact pads 11, a rigid square support 69 can be provided having two surfaces 69c, 69d pressing against two surfaces 67c, 67d of the body 61, respectively opposite to the surfaces 67a, 67b.

In the embodiment illustrated in FIGS. 13 to 15, the conductive elements 83 are identical to those of the embodiment in FIGS. 4 to 6. The body 81 made of insulating elastic material of the embodiment of FIGS. 13 to 15 differs from the body 61 of the embodiment of FIGS. 10 to 12 in that the rectilinear parts 82a, 82b of the conduit 82 extend beyond the intersection between these two rectilinear parts. The conductive elements 83 are introduced into the rectilinear parts 82a, 82b of the conduit so that their respective contact surfaces 88 are located in the plane Q (FIG. 15) defined by the two directions of the rectilinear parts 82a, 82b of the conduit (plane of the Figures 13 and 14).

FIG. 16 illustrates a variant of a conducting element 103 usable in the device when a component to be interconnected has holes intended to receive contact pins. The conductive element 103 comprises a rod 104 and a head 105, a support shoulder 106 being formed between the rod 104 and the head 105. On the side opposite the shoulder 106, the head 105 comprises a pin 120, intended for the connection to the component to be interconnected.

In the example shown in Figure 16, the rod 104 of the element 103 has a conical end 108 on the side opposite to the head 105. Such a pointed shape of the end 108 facilitates the introduction of the conductive element 103 in a conduit of smaller cross section, as in the example of FIGS. 1 to 3 and 10 to 12. Furthermore, this pointed shape can make it possible to produce the conduit by driving the conductive elements 103 into a solid elastic body, the pointed end 108 perforating the material of the body to form the conduit which then behaves like the preformed conduits 2, 62, 82 previously described.

Figures 17 and 18 show a variant of the embodiment of the device shown in Figures 1 to 3. According to this variant, the rod 4 of each of the two identical conductive elements 3 comprises a cylindrical part extended by a conical end 4a. When the conductive elements 3 are introduced into the duct 2, their respective contact surfaces 8 formed by the conical ends 4a are parallel to each other and form an angle A with the plane P (FIG. 17). In this way, when the conductive elements 3 introduced into the conduit 2 are pushed axially towards one another, they tend to slide along their respective contact surfaces 8 while maintaining contact between these two surfaces. The device according to this variant embodiment is in fact the best embodiment and gives whole satisfaction with the pressure and support properties of the contacts.

Several possible embodiments of the invention have been described, but it will be understood that various modifications can be made to these examples without departing from the scope of the invention.

Thus, the body of elastic material can take various forms depending on the number of interconnections to be made and the geometry of the components to be interconnected. An advantage of the realization of the body in elastic material is that it can be given a shape ensuring the seal between the components to be interconnected.

The device according to the invention can have various applications. It can for example be inserted in an electronic assembly to interconnect several integrated or printed circuits. It can also be inserted into a connector to give it good contact pressure, support and possibly sealing properties.

Claims (12)

1. Electrical interconnection device comprising a body of elastic insulating material (1; 61; 81) through which extends at least one duct (2; 62; 82) and at least one conducting means (3; 23; 43; 63; 83; 103) inserted into the duct to provide an electrical connection between two components (10) to be interconnected which exert upon the conducting means a pressure elastically deforming the body of elastic material (1; 61; 81) for ensuring the elastic maintaining of the electrical connection between both components (10), the conducting means comprising two bearing parts (6; 26; 46, 56; 106) applied upon the body (1; 61; 81) in the vicinity of the duct to prevent the complete penetration of the conducting means into the duct, characterized in that the conducting means comprises two conducting elements (3; 23; 43; 63; 83; 103) inserted into the duct (2; 62; 82) and comprising two rods (4; 24; 44; 104), respectively, penetrating into the duct and comprising two contact surfaces (8; 28; 48, 58; 68; 83), respectively, intended to make an electrical contact between both conducting elements and in that in the position of interconnection of both components (10), an axial pressure is exerted upon each conducting element (3; 23; 43; 63; 83; 103) and deforms the elastic body (1; 61; 81) through the medium of both bearing parts (6; 26; 46, 56; 106) located at both ends, respectively, of both rods (4; 24; 44; 104) opposite to those comprising the contact surfaces so as to ensure a contact pressure between the contact surfaces of the conducting elements (3; 23; 43; 63; 83; 103).
2. Device according to claim 1, characterized in that at least one of the aforesaid conducting elements comprises a head (5; 25; 45; 105) located outside of the duct (2) and in that the aforesaid bearing portion of the conducting elements comprises a shoulder (6; 26; 46; 106) formed between the rod (4; 24; 44; 104) and the head of the conducting element.
3. Device according to claim 2, characterized in that the head (5; 25; 45) of the conducting element (3; 23; 43) has a bulged form on the side opposite to the shoulder (6; 26; 46) and is in electrical contact with one of the aforesaid components (10) exerting the aforesaid axial pressure upon the conducting element.
4. Device according to claim 2, characterized in that the head (105) of the conducting element (103) comprises a pin (120) on the side opposite to the shoulder (106), intended for the connection of one of the components (10) to be interconnected exerting the aforesaid axial pressure upon the conducting element (103).
5. Device according to one of claims 1 to 4, characterized in that the duct (2) is substantially rectilinear and the respective contact surfaces (8; 28; 48, 58) of the conducting elements (3; 23; 43, 51) inserted into the duct (2) form an angle (A) with a plane (P) perpendicular to the direction (D) of the duct (2).
6. Device according to claim 5, characterized in that the aforesaid conducting elements (3) comprise two adjacent conical ends (4a), respectively, forming the aforesaid contact surfaces (8).
7. Device according to one of claims 1 to 4, characterized in that the duct (2) is substantially rectilinear and in that the contact surfaces (28; 48, 58) of the conducting elements (23; 43, 51) inserted into the duct (2) are substantially parallel to the direction (D) of the duct.
8. Device according to claim 7, characterized in that the contact surface (48) of one conducting element (43) inserted into the duct (2) has a concave shape defined by generating lines substantially parallel to the direction (D) of the duct and conforming to the complementary convex shape of the contact surface (58) of the other conducting element (51) inserted into the duct (2).
9. Device according to one of claims 1 to 4, characterized in that the duct (62; 82) comprises two rectilinear portions (62a, 62b; 82a; 82b) forming an angle therebetween and in that one conducting element (63; 83) is inserted into each rectilinear portion of the duct, the electrical contact between the contact surfaces (68; 83) of the conducting elements (1; 61; 81) being made at the intersection of both rectilinear portions (62a, 62b; 82a, 82b).
10. Device according to claim 9, characterized in that each conducting element (63; 83) inserted into one rectilinear portion (62a, 62b; 82a, 82b) of the duct (62; 82) has its contact surface (68; 88) forming an angle with a plane (Pa, Pb) perpendicular to the direction (Da, Db) of the said rectilinear portion.
11. Device according to claim 10, characterized in that the contact surfaces (88) of the conducting elements (83) inserted into the duct (82) are substantially parallel to the plane (Q) defined by both directions of the rectilinear portions (82a, 82b) of the duct.
12. Device according to one of the foregoing claims, characterized in that each conducting element (3; 63) inserted into the duct (2; 62) has a cross-section greater than the cross-section of the duct and thus elastically deforms the cross-section of the duct in order to retain the conducting element within the elastic body.

Images