WO2012069865A1

WO2012069865A1 - Connector assembly

Info

Publication number: WO2012069865A1
Application number: PCT/IB2010/003167
Authority: WO
Inventors: Thomas Bernhard Pabst
Original assignee: Fci Automotive Holding
Priority date: 2010-11-22
Filing date: 2010-11-22
Publication date: 2012-05-31

Abstract

The present invention relates to a connector assembly adapted to be connected to a cable (300). The connector assembly comprises a connector housing and a cable strain relief device (200), whereby the cable strain relief device (200) is adapted to provide a shielding continuity for the cable (300) shielding and is a single integrated member. The cable strain relief device (200) comprises a shielding contact portion which is adapted to establish an electrical connection to a shielding portion (301) of the cable (300), and at least one cable fixing portion which is adapted to provide a cable (300) strain relief attachment of the cable (300) to the housing.

Description

Connector assembly

1. Field of the invention

The present invention relates to an electrical connector assembly with a cable strain relief device.

2. Technical background

In many fields of applications, electrical connector assemblies require cable strain relief devices which firmly attach cables to these connector assemblies in order to relief the actual connection portion of the cable from possible strains. This connection portion, where e.g. the cable is stripped and the cable wires may be connected to a contact terminal can be particularly fragile and therefore has to be protected. Further, it is often important that cables and their connections are electromagnetically shielded. In particular with growing complexity of electronic circuits e.g. in the automotive sector shielding of connectors and cables is an essential need to avoid possible interferences, or damage caused by voltages which can be induced by electromagnetic energy. Therefore, in particular signal transmitting electrical cables as well as high power cables have to be continuously shielded against electromagnetic influences.

Such a continuous shielding is often particularly difficult to achieve just at the above mentioned connection portion of the cable. To allow for the electrical connection to a contact terminal the connection portion has to be stripped, i.e. et least the cable isolation is removed. Therefore, to allow for a shielding continuity covering this stripped portion, it is often necessary to electrically bridge the cable shielding to the shielding member of a corresponding counter connector. A typical prior art example of establishing a shielding continuity is given in the US document no. 4,547,623. This document describes how electrically connecting the shielding of a cable to a metal connector housing to achieve a shielding continuity in a connector assembly. To establish this connection, the cable isolation is removed from a cable part close to the cable connection portion, thereby uncovering the cable shielding. An arrangement of different metal rings is arranged within this stripped portion of the cable in electrical contact with the cable shielding. In assembled condition of the connector assembly, this ring arrangement is further in electrical contact with the inner surface of the conductive metal connector housing, thereby electrically connecting the cable shielding to the connector housing. Thus, by this electrical connection, a shielding continuity throughout the connector assembly is provided, covering in particular the stripped cable connection portion. Due to the large demand for electrical components, e.g. in the field of automotive applications, such components have to be efficiently and inexpensively manufactured, however, they still have to comply with high quality standards. Therefore, it can be of great advantage if extra parts can be saved, by incorporating their functions into unavoidable parts.

An example of a connector assembly with a further developed way of establishing a shielding continuity is described in US-document no. 5,848,914. This document discloses to avoid extra shielding connection members by connecting a metal connector housing directly to the cable shielding, thereby establishing a shielding continuity for the electrical cable. However, the US '914 requires electroconductive connector housings, which may not always be desirable.

It is an object of the present invention, to improve the state of the art by providing an improved connector assembly with an improved way of establishing shielding continuity and strain relief. It is a further object of the present invention to provide a connector assembly with a more flexible way of establishing shielding continuity and strain relief which can e.g. be used with non-conductive and conductive connector housings. It is an even further object of the present invention to provide an improved connector assembly which can be easily assembled in a mass-production process. It is still an even further object of the present invention, to achieve all the advantages with an expensive product, which can preferably be made from sheet metal parts and parts manufactured by injection moulding.

These and other objects which become apparent upon reading the following description.

3. Summary of the invention

According to the invention, a connector assembly is provided which is adapted to be connected to a cable, as for example to an electromagnetically shielded cable for signal or high power transmission. The connector assembly comprises a connector housing, which preferably is manufactured by injection moulding and a cable strain relief device. The cable strain relief device is a single integrated member and is adapted to provide a shielding continuity for the cable shielding. It comprises a shielding contact portion which is adapted to establish an electrical connection to a shielding portion of the cable, and at least one cable fixing portion which is adapted to provide a cable strain relief attachment of the cable to the housing. Thus, the inventive cable strain relief device incorporates the function of a strain relief device as described above, and the function of a shielding continuity member in a single integrated component.

In addition to this advantageous combination of different functions in only one single component, in a preferred embodiment, the inventive construction allows for a particularly efficient assembling of the connector assembly. Upon mounting of the cable strain relief device to the connector assembly, both of its above mentioned functions, i.e. its electrical connection to the cable shielding, as well as its function to provide cable strain relief attachment for a cable, are provided in a single working step. In other words, in one single working step, the cable strain relief device provides the shielding continuity for the cable shielding, while it firmly attaches the cable to the connector housing. Due to the inventive construction of the cable strain relief member no extra working steps are required. As a result, the inventive cable strain relief device is an electrical component ideally suited to be used in mass-production assembling.

This inventive construction is reflected in an advantageous design of the shielding contact portion and the cable fixing portion. Preferably, the shielding contact portion comprises at least one flexible latching contact which extends in a direction essentially perpendicular to the cable orientation. This flexible latching contact is adapted to clampingly engage the shielding portion of the cable when the strain relief device and the cable are mounted to the connector housing. In other words, upon mounting of the cable strain relief device to the connector housing, the flexible latching contact snaps around the cable shielding, whereby it provides the electrical connection between the cable strain relief device and the cable shielding. The cable fixing portion provides the above mentioned firm attachment of the cable to the connector assembly in order to relief the cable connection portion from any possible strain, such as it can occur during assembly, maintenance or use of electrical components which are further connected to this cable. Therefore, the cable strain relief device can be firmly connected to the cable, respectively the insulating cable sheathing, as well as it can be locked to the connector housing. In a preferred embodiment, for these purposes, the cable fixing portion comprises at least one cable fixing tooth. To firmly connect the cable strain relief device to the cable, the cable fixing tooth cuts into an outer portion of the cable, i.e. an outer portion of the insulating cable sheathing. To lock the cable strain relief device to the connector housing, the cable fixing tooth is preferably inserted into a locking slot of the connector housing. For example, upon mounting the cable strain relief device to the connector housing, the cable fixing tooth may be inserted into a locking slot provided e.g. in the interior of the connector housing, in which it prevents movements of the cable strain relief device with respect to the connector housing. Preferably, the cable fixing tooth cuts into an outer portion of the cable sheathing upon being mounted to the connector housing. For example, while the cable strain relief device is being mounted to the connector assembly, the cable fixing tooth is inserted into the locking slot, while the flexible latching contact engages the cable shielding. Upon continuation of mounting, the cable fixing tooth moves through the locking slot and cuts into said outer portion of the cable sheathing, while the latching contact snaps around the cable shielding. With the cable fixing tooth being inserted into the locking slot and cut into the cable isolation, the strain relief device is firmly connected to the cable while it is locked to the connector housing. Thus, it firmly attaches the cable to the connector housing, thereby providing the strain relief attachment for the cable which relieves the cable connection portion. Preferably, the cable strain relief device can be fixedly attached to the cable without any crimping action. In a preferred embodiment the cable strain relief device provides a shielding of at least 40 dB, preferably at least 55 dB, most preferably at least 70 dB in the range of 10 kHz - 5 MHz and at least 20 dB, preferably 30 dB, most preferably 40 dB in the range of 5 MHz - 500 MHz. 4. Description of the preferred embodiments

In the following, the invention is described exemplarily with reference to the enclosed figures in which: Fig. 1 shows a schematic illustration of a preferred embodiment of a cable strain relief device in accordance with the invention; Fig. 2 shows the cable strain relief device of Fig. 1 in a different perspective;

Fig. 3 shows the cable strain relief device of Figs. 1 and 2 mounted to a connector housing;

Fig. 4 shows the cable strain relief device of Figs. 1, 2 and 3 mounted to a cable;

Fig. 5 shows the cable stain relief device and the cable of Fig. 4 in a different perspective;

Fig. 6 shows a first half of a connector housing with the cable mounted to this first half of the connector housing and the cable strain relief device not yet mounted; Fig. 7 shows the first half of a connector housing of Fig. 6 with the cable and the cable strain relief device being mounted to this first half of the connector housing;

Fig. 8 shows an assembled connector assembly in accordance with the invention. Fig. 1 shows a perspective view of a cable strain relief device 200 in accordance with the invention. In Fig. 2, the cable strain relief device 200 of Fig. 1 is shown from a different perspective. As one can see in Figs. 1 and 2, two flexible latching contacts 201 extend from a shielding contact portion 210 in directions essentially perpendicular with respect to a flat base portion 205. The base portion 205 is depicted as an essentially flat surface; however in different embodiments the surface may be provided with further locking or latching members or may not be formed as a flat surface. The flexible latching contacts 201 are bent outwards forming a clip collar. As it will be clear to the person skilled in the art, by means of this clip collar, the cable strain relief can be clamping engaged with a cable shielding within a stripped portion of a cable (not shown in fig. 1 and 2). In other words, upon mounting the cable strain relief device to the connector assembly, the two flexible latching contacts 201 snap around the cable shielding of the cable. As one can best derive from Fig. 4, the flexible latching contacts 201 extend in directions essentially perpendicular to the cable orientation. This cable orientation (as indicated by arrow 601) refers to the main orientation of the cable within the section in which it is connected to the cable strain relief device 200. Because the cable strain relief 200 is preferably made of conductive sheet metal, by being mechanically attached to the cable shielding, it is also electrically connected to the cable shielding, and thus, as the skilled in the art will recognize, it can provide a shielding continuity for the cable shielding.

Further, two edges of the flat base portion 205 are formed as serrated edges 207 which extend essentially parallel to the cable orientation, whereby each serrated edge 207 comprises two inclined edges 209. Each of these inclined edges 209 forms an angle γ with respect to the cable orientation as indicated in Fig. 1. The size of this angle γ is within a range of 0° to 90°, preferably within a range of 30° to 70°, more preferably within a range of 40° to 60° and most preferably within a range of 45° to 55°. A cable fixing tooth 203 extends from each of these inclined edges 209 in a direction essentially perpendicular to the base portion 205, and in a direction essentially parallel to the flexible latching contact 201.

These cable fixing teeth 203 are adapted on one hand to lock the cable strain relief device 200 to a connector housing (not shown in Fig. 1 and 2), while they are on the other hand adapted to connect the cable (not shown) to the cable strain relief device 200 such that movements of the cable with respect to the cable strain relief device 200 and thus with respect to the housing are prevented. In the figures one can see that each cable fixing tooth 203 is provided with one stop face 217, which in assembled condition of the connector assembly serves to interact with a locking portion of the connector housing (not shown in the figures) for locking the cable strain relief device 200 to the connector housing. By this locking interaction, a movement of the cable strain relief device 200 in one direction parallel to the cable orientation is prevented, which in the shown case is for example a direction opposing the direction as indicated by arrow 601. To inhibit a movement in a further direction essentially parallel to the cable orientation (in the shown case essentially in direction of arrow 601), the cable strain relief device 200 is provided with at least one further stop surface 221.

In Fig. 3 the cable strain relief device 200 is shown being mounted to a connector housing 400 in a partially cut view, whereby each cable fixing tooth 203 is inserted into a locking slot 401 of the connector housing 400. As one can see, the stop faces 217 of the cable fixing teeth 203 are blocked inside locking slots 401. As one can further see, the flexible latching contacts 201 are inserted into slots 407. Thereby, an additional locking mechanism is provided, which prevents movements of the cable strain relief device 200 with respect to the connector housing 400 which are essentially parallel to the arrow 601. Figs. 4 and 5 show the cable strain relief device 200 connected to a cable 300. As the person skilled in the art knows, the cable 300 is a coaxial cable, which comprises an insulating cable sheathing 303, a cable shielding 301 and cable wires 307 with wire insulation 311. Reference numeral 305 indicates the cable connection portion, in which cable and the wire are stripped, such that an electrical connection, e.g. to a contact terminal (not shown) can be established. In these figures, the flexible latching contacts 201 are snapped around a cable shielding 301, whereby a movement of the cable strain relief device 200 in a direction essentially perpendicular to the cable orientation (arrow 601) is prevented. As one can see, the cable fixing teeth 203 cut into an outer sheathing portion 303 of the cable 300, i.e. the cable isolation. To facilitate mounting of the cable strain relief device 200 to the cable 300, and cutting the cable sheathing 303, each cable fixing tooth 203 is provided with the blade edge 211 which preferably comprises at its free end 213 a rounded corner 215 to facilitate insertion into slots 401. Regarding these figures, it is clear to the person skilled in the art, that when the cable strain relief device 200 is connected to the cable as shown in Figs. 4 and 5, while it is itself locked to the connector housing (not shown), a possible strain acting on the cable 300 is transmitted to the cable strain relief device 200 and thereby to the connector housing. Thus, the connection portion 305 of the cable, in which in the figure the stripped cable wires 307 are visible, is relieved.

As a result, the four cable fixing teeth 203 form a cable strain relief portion, which attaches the cable to the cable stain relief 200 and thereby in assembled condition to the connector housing (shown in Fig. 7). Thereby, in particular movements of the cable in directions opposing arrow 601 are prevented, which in assembled condition could destroy mechanical connections of the cable wires 307 to e.g. contact terminals. Therefore, as it will be clear to the person skilled in the art, it is not necessary that the cable strain relief portion consists of exactly four cable fixing teeth 203. In different embodiments of the invention, the cable strain relief portion could be provided with less or more cable fixing teeth 203.

Figs. 6 to 8 demonstrate a preferred way of assembling a connector assembly in accordance with the invention. The connector assembly comprises a connector housing 400, assembled from two parts and the cable strain relief device 200. Fig. 6 shows a cable 300 inserted into a first half 402 of the connector housing 400. In this figure - within the connection portion 305 of cable 300 - one can see the cable wires 307 which are for example connected to a contact terminal (not shown). As one can derive from Figs. 6 and 7, upon mounting the cable strain relief device 200, it is pushed along its insertion direction as indicated by arrow 603 into the connector housing 400 (of which in Figs. 6 and 7 only a first half 402 is visible). To further secure the locking mechanism, each cable fixing tooth 203 is provided with a latching wing 225 (visible in Fig. 6).

In Fig. 7 the cable strain relief device 200 is shown mounted to cable 300 and the first half 402 of the connector housing 400. As described in detail above, by mounting the cable strain relief device 200 to the cable 300 and the connector housing 400 simultaneously, an electrical connection between the cable strain relief device 200 and the cable shielding 305 is established and a strain relief between cable and housing. Thus, the attachment of the cable 300 to the connector housing 400 is achieved at the same time when the electrical connection between the cable strain relief 200 and the cable shielding 305 is established, in only one single working step.

Fig. 8 shows the assembled connector assembly 100 after the second half 404 of the connector housing 400 is mounted to the first half 402. This second connector half 404 is drawn translucent, such that it is possible to view internal components of the connector assembly 100. As one can see in the figure, the cable strain relief device 200 is mounted to cable 300 providing a shielding continuity for the cable shielding 301. To continue the shielding throughout the connector assembly, the cable strain relief device 200 may be in electrical contact for example with a shielding sleeve which is mounted inside the connector housing around the contact terminal (not shown). Instead of a separate shielding sleeve, the inner faces of the connector housing could be made from metal, or could be metallized, for being electrically connected to the cable strain relief device 200.

Claims

Connector assembly (100) adapted to be connected to a cable (300), comprising a connector housing (400) and a cable strain relief device (200) which is adapted to provide a shielding continuity for the cable (300), the cable strain relief device (200) being a single integrated member comprising a shielding contact portion (205) adapted to establish an electrical connection to a shielding portion (301) of the cable (300), and at least one cable fixing portion adapted to provide a cable strain relief attachment of the cable (300) to the housing.

Connector assembly (100) according to claim 1 , wherein the shielding contact portion (210) and the cable fixing portion are adapted to allow providing the electrical connection and the cable strain relief attachment in a single working step upon mounting of the cable strain relief device (200) to the connector assembly (100).

Connector assembly (100) according to any one of claims 1 and 2, wherein the shielding contact portion (210) comprises at least one flexible latching contact (201) which extends in a direction essentially perpendicular to the cable orientation, and which is adapted to clampingly engage the shielding portion (301) when the cable strain relief device (200) is mounted to the connector housing (400) and the cable (300) is mounted, thereby providing the electrical connection. Connector assembly (100) according to any one of the preceding claims, wherein the cable fixing portion comprises at least one cable fixing tooth (203) for locking the cable strain relief device (200) to the connector housing (400), whereby said cable fixing tooth (203) is adapted to be inserted into a locking slot (401) of the connector housing (400), when the cable strain relief device (200) is mounted to the connector housing (400).

Connector assembly (100) according to any one of the preceding claims, wherein the cable fixing tooth (203) cuts into an outer portion (303) of the cable (300), when the cable strain relief device (200) is mounted to the connector housing (400), thereby providing the cable relief attachment.

Connector assembly (100) according to any one of the preceding claims, wherein the cable strain relief device (200) further comprises an essentially flat base portion (205), which extends essentially parallel to the cable orientation.

Connector assembly (100) according to any one of the preceding claims, wherein the base portion (205) comprises at least one serrated edge (207), whereby this serrated edge (207) extends essentially parallel to the cable orientation.

Connector assembly (100) according to any one of the preceding claims, wherein, within the serrated edge, the base portion comprises at least one inclined edge (209), from which the at least one cable fixing tooth (203) extends in a direction essentially perpendicular to the base portion (205).

Connector assembly (100) according to any one of the preceding claims, wherein the flexible latching contact (201) extends essentially in a direction perpendicular to the base portion and is adapted to electrically contact the shielding portion (301) of the cable (300). Connector assembly (100) according to any one of the preceding claims, wherein the cable fixing tooth (203) comprises at least one blade edge (211) to facilitate cutting of the cable fixing tooth (203) into the outer portion of the cable (300), whereby this blade edge (211) preferably extends in a direction towards a free end (213) of the cable fixing tooth (203) and said free end (213) comprises a rounded corner (215).

Connector assembly (100) according to any one of the preceding claims, wherein the cable fixing tooth (203) is provided with at least one latching wing (225), which is adapted to hamper a movement of the cable strain relief device (200) in a direction opposing its insertion direction into the connector housing (400).

Connector assembly (100) according to any one of the preceding claims, wherein the cable fixing tooth (203) is provided with at least one stop face (217), which in assembled condition of the connector assembly (100) interacts with a locking slot (401) of the connector housing (400) thereby inhibiting a movement of the cable strain relief device (200) with respect to the connector housing (400) in a direction essentially parallel to the cable orientation.

Connector assembly (100) according to any one of the preceding claims, wherein the shielding contact portion (210) is formed as a clip collar.

Connector assembly (100) according to any one of the preceding claims, wherein the cable strain relief device (200) can be fixedly attached to the cable (300) without any crimping action. 15. Method of assembling a Connector assembly (100) comprising the following steps: providing a connector assembly (100) according to any one of claims 1-14;

providing a cable (300) with a cable shielding;

mounting the cable (300) to the connector housing (400);

mounting the cable strain relief device (200) to the connector housing (400), whereby an electrical connection between the cable strain relief device (200) and a shielding portion (301) of the cable (300) is established, while simultaneously the cable fixing tooth (203) is inserted into the locking slot (401) of the connector housing (400) and cuts into an outer portion (303) of the cable (300), thereby attaching the cable (300) to the connector housing (400).