Modular Backshell Housing

A backshell housing includes a pair of housing parts including a first housing part and a second housing part friction welded to one another. A cable passage of the first housing part is continuous with a cable passage of the second housing part.

FIELD OF THE INVENTION

The invention relates to a backshell housing for receiving a cable and adapted to be attached to a connector. The invention further relates to a set and a method for assembling such a backshell housing.

BACKGROUND

A backshell housing may be mounted on the rear end of a connector, providing a cable passage for inserting a cable into the connector. The backshell housing may be designed to help protect connections from mechanical wear, environmental conditions, and electromagnetic interference (EMI). Therefore, backshell housings are a valuable asset in electronic systems. However, depending on the application, customers may have specific requirements for the size and shape of the backshell housing. When the backshell housing is constructed from a composite material, a different die or mold for every variation of the backshell housing is necessary, which increases production costs.

SUMMARY

A backshell housing includes a pair of housing parts including a first housing part and a second housing part friction welded to one another. A cable passage of the first housing part is continuous with a cable passage of the second housing part.

DETAILED DESCRIPTION OF THE EMBODIMENT(S)

In the following, the invention is explained in greater detail with reference to the accompanying drawings, in which exemplary embodiments are shown. In the figures, the same reference numerals are used for elements, which correspond to one another in terms of their function and/or structure. According to the description of the various aspects and embodiments, elements shown in the drawings can be omitted if the technical effects of those elements are not needed for a particular application, and vice versa: i.e. elements that are not shown or described with reference to the figures can be added if the technical effect of those particular elements is advantageous in a specific application.

A first embodiment of an inventive backshell housing1is described with reference toFIG. 1. The backshell housing1for receiving a cable2and adapted to be attached to a connector4, such as an electric connector and/or a fiber-optic connector or a hybrid connector, comprises at least two housing parts6, wherein the at least two housing parts6are friction welded to one another. Each housing part6of the at least two housing parts comprises a cable passage8, the cable passage8of a first housing part10of the at least two housing parts6being continuous with the cable passage8of a second housing part12of the at least two housing parts6.

The at least two housing parts6may be formed by a thermoplastic material, particularly a polyimide, such as polyetherimide. To further reinforce the strength and/or stiffness of the material, the material may be further reinforced by glass fibers.

The at least two housing parts6are joined together by friction welding, allowing for a rigid and stable connection without having to introduce a further component such as an adhesive, which would dissolve during a plating process. The orientation of the housing parts6relative to one another, particularly the rotational orientation, may be determined individually for each backshell housing1during the welding process. Consequently, it is possible to manufacture different variations of the backshell housing1without having to provide a costly die for each variation.

In the figures, a cut section is shown to demonstrate the interaction between the at least two housing parts6. However, it is acknowledged that the welding features14shown in the figures may actually only be visible before the welding process and are just shown for demonstrative purposes. After welding, a continuous section of material may be formed at a joint between the at least two housing parts6. No or only little gaps, e.g. air gaps, are formed in the welded joint, further increasing the strength and reliability of the joint.

In an embodiment, the at least two housing parts6are spin welded to one another. During spin welding, one housing part of the at least two housing parts6is held stationary while the other housing part6is rotated and pressed against the stationary housing part6. Due to the friction generated between the housing parts6, the material of the at least two housing parts, at least at the interface between the at least two housing parts6, melts. During the cooling period after the material has melted, the two housing parts6are pressed together in a predetermined relative rotational position to one another, rigidly connecting the at least two housing parts6in that predetermined position. Furthermore, during spin welding, the heat is evenly generated circumferentially at the interface between the housing parts6forming a strong weld having essentially the same resistance to fracture in each radial direction, e.g. due to a high bending moment.

FIG. 1shows an embodiment of the backshell housing1, wherein the backshell housing1is adapted to extend along a longitudinal axis L from a rear end of the connector4. The backshell housing1comprises two housing parts6, wherein the first housing part10is a connector end part14adapted to be attached to the connector4and the second housing part12is a cable end part16having a cable inlet opening18for receiving the cable2.

In an embodiment, the connector4may be a connector interface28adapted to mount the backshell housing1to a further connector, e.g. a plug connector. The connector end part14is shown inFIG. 3and the cable end part16is shown inFIG. 4. The connector interface28may for example be a coupling nut, which can receive the backshell housing1on one end and be rigidly mounted to the plug connector4, particularly a housing of the plug connector4, e.g. by a threaded connection.

The cable inlet opening18may be adapted to the diameter of the cable2, so that the cable end part16may at least partially be sleeved around the cable2providing an additional strain relief. The cable end part16may comprise an essentially cylindrical shape having a neck20at a free end forming the cable inlet opening18. Opposite the free end, the cable end part16may comprise a flange22protruding radially from the neck20, as shown inFIGS. 1 and 4. The flange22may comprise a front face24having an annular welding protrusion26arranged coaxially with the cable passage8of the cable end part16and protruding axially from the front face24.

The connector end part14, shown inFIGS. 1-3, may be adapted to be attached to the connector interface28. In the shown exemplary embodiments, the connector end part14is adapted to be received in a rear end of the connector interface28. In an embodiment, the connector end part14comprises an essentially hollow cylindrical shape having an annular slot30formed along the outer circumference of the connector end part's14body being arranged between two radially protruding collars32. A latch34of the housing, shown inFIGS. 1 and 2, may be received in the annular slot30in order to secure the connector end part14in the connector interface28by a positive fit, preventing a relative movement of the connector end part14and the connector interface28essentially parallel to the longitudinal axis L. The latch34may be a retention ring, i.e. a circlip, fastening the connector end part14to the connector interface28.

The connector end part14may be adapted to be mounted in a housing of the connector, particularly a rear opening of the housing. The connector end part14may be adapted to be attached to the connector interface28, which may comprise a cavity at a rear end for at least partially receiving the connector end part14.

The cable passage8at the connector end part14may comprise a larger diameter than the cable passage8of the cable end part16, at least at the neck20, allowing the cable2to radially move within the cable passage8.

A front face36facing away from the connector4comprises a circumferential frame38, shown inFIGS. 1 and 3, framing an opening of the cable passage8. The frame38may further comprise a welding notch40extending from the front face36into the frame38essentially parallel to the center axis of the cable passage8. The welding notch40may be annular and may be arranged coaxially with the cable passage8and be adapted to receive the welding protrusion26formed on the cable end part16.

As shown inFIGS. 3 and 4, the welding notch40may comprise a depth42in the axial direction smaller than a length44in the axial direction of the welding protrusion26. Therefore, prior to welding, the front faces24,36of the respective housing parts14,16may be distanced from one another so that only the welding protrusion26and the welding notch40may be melted due to the heat generated by the friction between the two parts.

Once the welding protrusion26starts melting, the housing parts14,16may be pushed together and held at a predetermined relative rotational position to one another. The excessive material of the welding protrusion26may further ensure that the welding notch40is completely filled with the material of the welding protrusion26for establishing a section of continuous material at the welding joint. It is possible to clearly define the moment at which the at least one welding protrusion26melts in the at least one welding notch40. When the at least one welding protrusion26melts, it is possible to insert the excessive length of the welding protrusion26into the notch40so that the opposing end faces abut one another, sealing the cable passage at the joint. The molten part may be pushed into narrow gaps between the remaining welding protrusion26and the notch40, increasing the welding quality and the welding strength at the joint.

In an embodiment, a plurality of separate notches40may be provided on the front face36arranged in an annular formation and a plurality of separate protrusions26on the other end face, each protrusion26being adapted to be received in a respective notch40. The friction may be generated by an oscillating movement or the like. Therefore, the relative rotational position of the housing parts14,16may be pre oriented prior to welding.

In another embodiment, in order to receive a uniform weld joint, the welding notch40and the welding protrusion26may have a continuous annular shape. Consequently, the housing parts14,16may be welded together having a continuous joint section. This may further increase the reliability of the joint, specifically, in terms of a maximum bending moment it may endure before breakage.

The first embodiment described with reference toFIG. 1is a simple backshell housing1extending along the longitudinal axis L from the rear end of the connector interface28. However, in many applications it is necessary to provide an angled backshell housing1for redirecting the cable2via the backshell housing1into the connector4. InFIG. 2, an exemplary embodiment of an angled backshell housing1is shown.

The backshell housing1shown inFIG. 2may form a 90° elbow46such that the cable passage8of the connector end part14and the cable passage8of the cable end part16are arranged in planes, which are inclined to one another at about 90°. The connector end part14and the cable end part16may be essentially structurally identical to the connector end part14and the cable end part16discussed with reference toFIGS. 1, 3 and 4. Consequently, the housing parts6may be standardized and provided in a set48for building a composite backshell housing1. Therefore, fewer different dies have to be provided in order to form a specific backshell housing1, reducing the manufacturing and storage costs.

At least one intermediate housing part50may be provided, the at least one intermediate housing part50being arranged between the first housing part10, i.e. the connector end part14, and the second housing part12, i.e. the cable end part16. The at least one intermediate housing part50may act as a spacer52adapted to increase the distance between two further housing parts6, as shown inFIG. 5, or form an elbow54, as shown inFIG. 6. The at least one intermediate housing part50may be arranged directly between two further intermediate housing parts, the cable end part16and the connector end part14, the cable end part16and a further intermediate part50and/or the connector end part14and a further intermediate part50.

The at least one intermediate housing part50may be adapted to be fiction welded to another housing part6at either end of the intermediate housing part50. Therefore, prior to welding, the intermediate housing part50may feature the welding protrusion26at one end and the welding notch40at the other end of the intermediate housing part50. Consequently, the intermediate housing part50may be fiction welded to a further intermediate housing part50, the connector end part14and/or the cable end part16.

The at least one intermediate housing part50may comprise an essentially cylindrical shape and may extend along a longitudinal axis L. Therefore, it is possible to increase the length of the backshell housing1may be extended along the longitudinal axis L by the at least one intermediate housing part50. The at least one intermediate housing part50may for example be about 5 mm or about 10 mm long. The length of the backshell housing1may be further increased by providing multiple intermediate housing parts50. In an embodiment, the multiple intermediate housing parts50may be structurally identical, so that it is not necessary to produce different housing parts. Multiple structurally-identical intermediate housing parts50may be stringed together without having to adjust the blank for manufacturing said intermediate housing parts50.

The intermediate housing part50forming the elbow54, shown inFIG. 6, may be bent around an approximate 45° angle, such that the respective front faces of each end are arranged in planes inclined to one another at an approximate 45° angle. Consequently, multiples of the 45° angle elbow may be formed by stringing together multiple structurally-identical intermediate housing parts50as shown inFIG. 2. InFIG. 2, two intermediate housing parts50forming the elbow54are friction welded, particularly spin welded to one another forming the composite elbow46of the backshell housing1. Therefore, different composite elbows46may be formed by stringing together standardized intermediate housing parts50.

It should be noted, that the 45° elbow of the intermediate housing part50inFIG. 6is just exemplary, and any other angle may be standardized, such as an approximate 30° angle. The elbow of the intermediate housing part50may be an integer of 90°, 120° and/or 180°. However, it has been found that the production of a larger angled intermediate housing part50is rather difficult. Thus, a smaller angle such as a 45° or 30° angle may be used as a standardized intermediate housing part50forming an elbow54.

For visually helping in determining the rotational position of the at least two housing parts6relative to one another, at least one of the at least two housing parts6may comprise at least one orientation feature56, such as a depression58formed on an outer surface60of the respective housing part6.

The depression58may further act as an interface for attachment of the tooling equipment during the friction welding process. The orientation feature56may help in determining the desired relative rotational position of the respective housing part6relative to the other housing parts6. Every rotational formation in the 360° is possible and can be determined during the friction welding process. Therefore, the number of possible backshell housing configurations can be increased even more.

Each housing part6shown inFIGS. 5 and 6may be formed as a monolithic unit62, such as an injection molded component64. Injection molding is a cost-efficient production method particularly for the production of the component in mass numbers. According to the invention, modular housing parts may be attached to one another by friction welding for forming the composite back shell housing1. Hence, the housing parts6may be standardized and provided in the set48, so that only a limited number of dies are necessary, greatly reducing the manufacturing costs. With the limited number of housing parts6, it is possible to form a great variety of structurally different back shell housings1.

In another embodiment, the housing part6may be formed as a multi component molded piece, wherein the welding protrusion26may be optimized for bonding with the material at the welding notch40during the friction welding process. A different material, being optimized for screening, sealing and chemical resistance, may form the remainder of the housing part6.

Further embodiments of a back shell housing1are depicted inFIGS. 7 and 8. The back shell housing1ofFIG. 7differs from the back shell housing1shown inFIG. 2in that two intermediate housing parts50are arranged as spacers52between the connector end part14and the composite elbow46. The spacers52may extend axially essentially parallel to the longitudinal axis L and may comprise different lengths in a direction essentially parallel to the longitudinal axis L. One spacer52may, for example, have a length of about 10 mm while the other has a length of about 5 mm. Thus, a composite spacer having a length of about 15 mm may be formed. The spacers52may be inserted individually or in combination as required at any point between the connector end part14and the cable end part16.

The back shell housing1ofFIG. 8comprises a composite elbow48formed by two elbow54intermediate housing parts, which are arranged in a different rotational position to one another, such that the respective elbows54are inclined to one another. In order to reduce the strain to the cable due to the abrupt change of direction of the cable passage, at least one spacer52may be provided between the two elbows54.