WO2010061249A1

WO2010061249A1 - Shielding shell

Info

Publication number: WO2010061249A1
Application number: PCT/IB2008/055661
Authority: WO
Inventors: Roland Tristan De Blieck
Original assignee: Fci
Priority date: 2008-11-28
Filing date: 2008-11-28
Publication date: 2010-06-03
Also published as: EP2371038A1

Abstract

A shield (1) for a connector is provided, the shield having a first edge (8) at a mating side (M) and a second edge (9) at a rear side (R) along the mating direction. The shield comprises a first shield portion (2) and a second shield portion (3) extending substantially in a mating direction (MD) from the mating side (M) to the rear side (R) and arranged at an angle to each other about the mating direction. The first shield portion comprises a plurality of first slots (5) having at least a portion extending substantially in the mating direction and defining spring elements (6). Also the second shield portion comprises a plurality of first slots (5) having at least a portion extending substantially in the mating direction and defining spring elements (6). The shield further comprises at least one second slot (11) extending from the first shield portion to the second shield portion and dividing the intermediate portion between the mating side and the rear side.

Description

SHIELDING SHELL

FIELD OF THE INVENTION

The present invention relates to electrical shields for connectors, in particular for shielding high frequencies.

BACKGROUND

It is common practice to interconnect electrical and/or electronic parts such as boards and/or cables with connector assemblies wherein one connector is configured to fit at least partially within another connector. It is well known that electronic signals to be transmitted by such connector assemblies may cause EMI emissions. This is particularly the case for high speed and/or frequency signals, such as about 1 gigabit per second and higher, and the effect tends to get worse for increasing signal frequencies. Such EMI emissions may cause electromagnetic disturbance to other neighbouring connector assemblies and/or electrical or electronic devices. Vice versa, one may want to shield from EMI disturbances the signals transmitted through a connector assembly.

Consequently, there is a desire for a shielding arrangement protecting from and/or preventing such EMI emissions. Generally, resilient gaskets and/or contact springs may be used for providing a conductive shielding arrangement. Contact springs may also provide a certain tolerance for true positioning of the connector and the counterpart to be mated, in particular for board-to-board connector assemblies.

SUMMARY

In an aspect of the invention, a shield is provided comprising a first edge at a mating side and a second edge at a rear side. Two shield portions are then defined extending between these edges: A first shield portion and a second shield portion extend substantially in a mating direction from the mating side to the rear side. These shield portions or shield walls and arranged at an angle to each other about the mating direction. For instance, they are perpendicular. An intermediate portion joins these two shield portions. At least one spring element is provided on the first, second and/or intermediate shield portions. More precisely, a spring element is formed by part of one of these portions.

Further, a slot extends from the first shield portion to the second shield portion and divides the intermediate portion somewhere between the mating side and the rear side.

The shield provides shielding in at least two directions by the first and second shield portions. The spring element located in the intermediate portion favours adaptation to misalignments or dimension differences between the shield and its counterpart when the connector parts are mated. It also allows a better adjustment between the shield and its counterpart .

Indeed, the intermediate portion being curved or bent will be relatively rigid compared to the first and second portions. This may increase the stresses during the mating operation. The slit allows distribution of a deformation over the edge and around the curve or angle provided by the intermediate shield portion. Advantageously, the slot in the intermediate portion may be in continuity, at least at one of its extremities, with one slot extending along the mating direction. This also favours the distribution of stresses to the adjacent first or second shield portions (depending on which of the shield portions the slot in the mating direction is adjacent to) . This may spare the shield, reduce the mating forces and increase the user- friendliness .

Advantageously, the slot in the intermediate portion may be in continuity, at each one of its extremities, respectively with one slot extending along the mating direction. In other words, the slot in the intermediate portion interconnects at least two slots (5) respectively located in the first and second shield portions. Then, the shield further allows increased deflection of the spring element and facilitates deflection of the first edge with respect to the rear side. This increases tolerance of the shield to the true position of the shield and a corresponding counterpart to be mated. Advantageously, at least one of the first and second shield portions comprises straight slots extending longitudinally in the mating direction. This provides spring elements that deflect essentially perpendicularly to the mating direction. This contributes to reduce potential gaps between the shield and a corresponding counterpart. This reduces the minimum wavelength of potential EMI emissions and thus increases effective shielding at elevated frequencies. Defining the spring elements by slots in the shield facilitates manufacturing of the shield and reduces the apertures through which EMI emissions may pass. Further, the (spring elements of the) shield provide (s) a relatively large and substantially linear flow path for electrical current between the contact portions of the spring elements and a further object to which the shield is (to be) contacted. The result is a reduced inductance for the shielding arrangement which improves the shielding efficiency, in particular for high frequencies and in particular compared to loose spring fingers such as cut out with U-shaped cuts.

The spring portions and/or the first edge may be deformed when mating the shield with a corresponding counterpart, e.g. due to deflection of the spring elements against the counterpart, due to inaccurate mating and/or due to the relative position of the shield and the counterpart with respect to a further object. Such deformation may produce stress in at least the first edge. Consequently, the first edge, is preferably substantially continuous along the entire mating side of the shield, so as to provide robustness to the shield and protects spring elements when mating the shield to a corresponding counterpart. "Continuous" means that the slots do not extend up to the edge. The second edge may also be continuous. This facilitates manufacturing and/or handling the shield. It may also facilitate mounting and/or attaching the shield to a further object such as a connector or a printed circuit board, e.g. by providing a substantially planar mounting facet. The shield may be a unitary object, e.g. a deep-drawn object, which may further improve its robustness and facilitate manufacturing.

Advantageously, the interconnection of spring elements at the rear side and the mating side assists preventing permanent deformation and/or breaking off of the spring elements, fortifying the spring elements and thus the shield as a whole.

The interconnection at the rear side may be due to the spring elements being mounted to a further object, such as a connector part or a printed circuit board. The interconnection at the mating side advantageously is to the first edge which may be substantially continuous, not being interrupted by the slots. This prevents individual spring elements from snagging to a further object and/or being bent in an undesired direction which may lead to permanent deformation and/or damage of the spring element. It further facilitates mating of the shield to a corresponding counterpart since the first edge provides a guiding function during at least the first stages of a mating operation.

The shield has advantageously a generally cylindrical shape. This provides shielding substantially fully around the shield. It may further facilitate handling and/or attachment to a further object such as a connector part and/or a printed circuit board.

An elongated cylindrical shape, e.g. an ellipsoidal, rectangular, trapezoidal or other polygonal shape such as a Sub- D connector, facilitates arranging a plurality of contact terminals within the connector to be provided with the shield. It further facilitates defining a mating orientation of the connector and corresponding counterpart.

With a shield having each one of its intermediate shield portions with a slot perpendicular to the mating direction, the deflection of the first edge with respect to the rear side is improved. This increases tolerance to the true position of the shield and a corresponding counterpart to be mated. In case the shield has a substantially narrow elongated shape with two relatively long sides and two relatively short intermediate portions on opposite short sides, the first edge(s) on the long sides may deflect substantially as a whole.

Advantageously, the slot of each intermediate portion comprises at least a portion arranged perpendicular to or at an acute angle to another portion of the second slot. Then, the slot of the intermediate portion (s) provides a reduced linear opening length both in a direction along the slot of the intermediate portion (s) and in a direction perpendicular to the slots parallel to the mating directions. This reduces the minimum wavelength of possible EMI emissions escaping through the slot of the intermediate portion (s) and thus increases effective shielding to elevated frequencies.

Adjacent spring elements may have different lengths, positions and/or widths. This may translate inter alia into different amounts of possible deflection of the spring elements, different contact pressure to a corresponding counterpart and/or different spring constants. Thus, the spring elements can be adapted to local different circumstances, e.g. for taking into account a general deflection and/or deformation of a shield portion. It also allows adaption of the spring elements for reasons of tolerances for true positioning and/or user- friendliness .

The invention will hereafter be more fully explained with reference to the drawings showing a number of exemplary embodiments .

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings,

Fig. 1 is a perspective view of a first embodiment of the invention, Fig. 2 is a perspective view of a second embodiment of the invention; and

Fig. 3 shows half a shield according to the invention seen from above.

DETAILED DESCRIPTION OF EMBODIMENTS

Fig. 1 shows a first embodiment of a shield 1 for a connector (not shown) . The shield 1 has a mating side M and a rear side R with respect to a mating direction MD.

The illustrated shield 1 has a generally rectangular cylindrical shape and comprises two opposed relatively long shield portions or walls 2 and two opposed relatively short shield portions or walls 3, all extending substantially in the mating direction MD. The long shield portions 2 and the short shield portions 3 are joined by curved intermediate shield portions 4, or corner portions, which are arranged in-between the long and short portions 2 and 3 and which arrange the short shield portions 3 at an angle to the long portions 2 about the mating direction MD. Here, the long and short shield portions 2, 3 are arranged substantially perpendicular to each other, such that the long and short shield portions 2, 3 are respectively and mutually substantially parallel. The intermediate shield portions 4 in this embodiment are smoothly curved, but they may be sharply bent or angled such that no meaningful radius of curvature may be determined.

The shield 1 comprises a plurality of first slots 5 extending substantially in the mating direction MD. Here, the first slots 5 on the long shield portions 2 define spring elements 6 between the first slots 5, which spring elements 6 also extend substantially in the mating direction MD. The short shield portion 3 comprises a generally U-shaped slot 5A, with portions extending in the mating direction MD, providing a cantilevered spring element 6A. Here, the spring elements 6 are interconnected towards the mating side M and towards the rear side R of the shield 1, adding robustness to the shield and reducing impedance of a contact between the shield 1 and a corresponding counterpart (not shown) . The spring elements 6, 6A comprise at least one contact portion 7.

In Fig. 1, the long shield portions 2 are divided in spring elements 6 by the first slots 5, without there being provided non-spring element shield portions. This improves the contact pressure to a corresponding counterpart and reduces gaps, which might cause EMI leakage.

The shield 1 comprises a first edge 8 at the mating side M of the shield 1 and a second edge 9 at the rear side R of the shield 1. Both the first and second edges 8, 9 extend along the long shield portions 2, the short shield portions 3 and the intermediate shield portions 4. The first and second edges 8, 9 are substantially continuous, not being interrupted by the first slots 5. Thus, the first and second edges 8, 9 provide robustness to the shield 1 and protection to the shield elements 6, as set out before. The shield 1 further comprises a flange 10 for mounting to a further object such as a connector part or a printed circuit board (not shown) . The shield 1 further comprises second slots 11 extending from the long portions 2 to the short portions 3 and dividing (or separating) the intermediate portions 4 somewhere between the mating side M and the rear side R. The second slots 11 interconnect adjacent slots 5 and 5A on adjacent shield portions. Due to the second slots 11, the first edge 8 of the shield 1 is resiliently connected with the remaining part of the shield 1. Deformation of spring elements 6 close to an intermediate shield portion 4 allows the first edge 8 to move with respect to the second edge 9, substantially without imparting bending stress in the first edge 8.

In the embodiment of Fig. 1, the second slot 11 is in continuity with the slot 5A. The U-shaped slot 5A is in continuity with a second slot 11. Consequently, a slot is formed which extends from one long shield portion 2 to the opposite long shield portion 2. Thus, the entire shield portion intermediate the two long shield portions 2 (i.e. the adjacent intermediate shield portions 4 and the short shield portion 3) is divided by a second slot. Hence, the first edge is further substantially free to move in a direction substantially parallel to the short shield portion 3, not being connected to that portion 3 anymore. The U-shaped slot portion 5A provides a portion arranged perpendicular to the first slots 5, which restricts the maximum wavelength of EMI radiation which may leak through it, compared to a substantially straight slot without such portion 5A.

Fig. 2 shows another embodiment of a shield 1, in which like objects and elements with respect to Fig. 1 are indicated with same reference signs. In Fig. 2, the short shield portions 3 comprise first slots 5 and spring elements 6, as on the long shield portions 2. In this embodiment, the second slots 11 extend between the long and short shield portions 2, 3, interconnecting adjacent slots 5 on adjacent shield portions 2, 3 and dividing the intermediate curved portions 4.

The shield 1 of Fig. 2 provides more robustness with respect to a relative movement of the first and second edges 8, 9 of the shield 1, by virtue that no any slot extends from one long shield portion 2 to the opposite long shield portion 2. In Fig. 2, the second slots 11 are generally (inverted) V-shaped providing portions arranged at an acute angle to the first slots and reducing possible leaking EMI radiation.

When EMI leakage along the short side of an elongated shield is not an issue, e.g. when the wavelength of the signal transmitted by the connector assembly, the second slot 11 may be substantially straight. It is even conceivable in such case to extend the slot 11 so as to substantially remove the second and intermediate shield portions 3 and 4 altogether and remain with the first shield portions 2 interconnected by the first and second edges 8, 9.

As may be appreciated from Figs. 1 and 2, the pitch between adjacent first slots 5 in the long shield portions may vary. Further, adjacent first slots 5 in at least one of the shield portions 2, 3 may differ in length. Thus, by one or both variations the width and/or length, respectively, of the spring elements 6 may be varied and therewith their resiliency and/or the extent of their deflection. Thus, the contact pressure of the spring elements onto a corresponding counterpart to be mated with the shield 1 may be adapted, as well as the mating force and/or user friendliness of the shield 1. This aspect may be employed for spring elements in general, e.g. for loose spring fingers 6A cut out by a U-shaped slot 5A.

Contact portions 7 of the spring element 6 may be provided with contact points, e.g. bumps or protrusions, or other means for improving contact, e.g. a local coating. Contact portions and/or contact points may be arranged on different height positions with respect to the mating side M and rear side R of shield 1, for adapting the contact pressure and mating force, e.g. for providing a gradually increasing mating force. This may be arranged by providing contact portions 7 at different positions in the mating direction along spring elements 6, and/or providing contact portions 7 in the middle of spring elements 6 having different positions and/or having different lengths in the mating direction MD.

The height of the contact portions on the spring elements may also be varied with respect to the internal face of shield. For instance, spring elements in the middle area of the second shield portions, i.e. the longer shield portions, may have a higher height than closer to the intermediate shield portions (see Fig. 3) . The height of the contact portions on the spring elements with respect to the internal face of shield may follow a curvature. As may further be appreciated from Figs. 1 and 2, the shield 1 may comprise means 15, such as latches and/or windows, for attaching to a connector part or other further object.

The present shield may be efficiently manufactured by deep drawing a conductive material, e.g. a metal, and providing it with the slots, e.g. by punching. As an alternative the shield may be made by cutting or stamping a suitable material, e.g. a sheet of metal, and forming the shield such as by folding. A shield may also be assembled from plural individual parts . The shield of the invention may be manufactured with a deep-drawn or from a metal belt with two opposite edges soldered so as form a cylindrical structure.

The invention is not restricted to the above described embodiments which can be varied in a number of ways within the scope of the claims. For instance, whereas the shown embodiments are substantially elongated rectangular structures, the shield need not be so shaped, and in particular need not be cylindrical. A generally L-shaped or U-shaped shield may also be provided in accordance with one or more of the appended claims. Whereas in the shown embodiments all spring elements extend towards the same side, i.e. towards an interior volume defined by the shield portions, spring elements may extend outward from an interior volume, and/or adjacent spring elements may extend to mutually different directions, e.g. to account for different shielding and/or connector arrangements.

Elements and aspects described with reference to different embodiments may be suitably combined within the scope of the appended claims.

Claims

1. Shield (1) for a connector having: a first edge (8) at a mating side (M) and a second edge (9) at a rear side (R) , a first shield portion (2) and a second shield portion (3) extending substantially in a mating direction (MD) from the mating side (M) to the rear side (R) and arranged at an angle to each other about the mating direction and joined by an intermediate portion (4), comprising at least a slot (11) extending from the first shield portion to the second shield portion and dividing the intermediate portion between the mating side and the rear side .

2. Shield according to claim 1, wherein the slot (11) in the intermediate portion is in continuity, at least at one of its extremities, with another slot (5) extending along the mating direction (MD) .

3. Shield according to claim 1 or 2, wherein the slot (11) in the intermediate portion is in continuity, at each one of its extremities, with another slot (5) respectively extending along the mating direction (MD) .

4. Shield according to any one of the preceding claims, wherein at least one of the first and second shield portions comprises straight slots extending substantially longitudinally in the mating direction and defining spring elements (6) between these straight slots.

5. Shield according to claim 4, wherein the spring elements are interconnected toward the rear side (R) and toward the mating side (M) of the shield.

6. Shield according to any one of the preceding claims, wherein the first edge (8) is continuous.

7. Shield according to any one of the preceding claims, wherein the second edge (9) is continuous.

8. Shield according to any one of the preceding claims, having a generally cylindrical shape.

9. Shield according to any one of the preceding claims, having a generally elongated cylindrical shape, wherein the first and second shield portions (2, 3) are respectively arranged substantially parallel to each other with a relatively narrow intermediate shield portion (4) arranged in-between the two relatively wide first and second shield portions (2, 3) .

10. Shield according to any one of the preceding claims, wherein the slot (11) of each intermediate portion comprises at least a portion (5A) arranged perpendicular to or at an acute angle to another portion of the second slot.

11. Shield according to any one of the preceding claims, wherein adjacent slots (5) extending in the mating direction in at least one of the first and second shield portions (2, 3) differ in length and/or position with respect to the mating side (M) and the rear side (R) of the shield.

12. Shield (1) according to any one of the preceding claims, wherein the pitch between adjacent slots (5) extending along the mating direction, in at least one of the first and second shield portions (2, 3), varies.

13. Shield (1) for a connector having: a generally cylindrical shape with a first edge at a mating side (M) and a second edge (9) at a rear side (R), a first shield portion (2) and a second shield portion

(3) extending substantially in a mating direction (MD) from the mating side to the rear side and are arranged at an angle to each other about the mating direction and joined by an intermediate shield portion (4), the first and second portions comprising a plurality of first slots (5) extending substantially in the mating direction and defining spring elements (6) between the first slots, the spring elements extending substantially in the mating direction and being interconnected toward the mating side and toward the rear side of the shield, the first and second edges being continuous and extending along the intermediate shield portion and the first and second shield portions, wherein the shield comprises at least one second slot (11) extending from the first portion to the second portion and dividing the intermediate portion between the mating side and the rear side.

14. Shield (1) for a connector having: a generally elongated cylindrical shape with a first edge (8) at a mating side (M) and a second edge (9) at a rear side (R) , a first shield portion (2) and a second shield portion (2) extending substantially in a mating direction (MD) from the mating side to the rear side, the first and second shield portions being respectively arranged substantially parallel to each other with a relatively narrow intermediate shield portion (4, 3, 4) arranged in-between the two relatively wide first and second shield portions, the first and second portions comprising a plurality of first slots (5) extending substantially in the mating direction and defining spring elements (6) between the first slots, the spring elements extending substantially in the mating direction and being interconnected toward the rear side and toward the mating side of the shield the first and second edges being continuous and extending along the intermediate shield portion and the first and second shield portions, wherein the shield comprises a second slot (11) extending from the first shield portion to the second shield portion and dividing the relatively narrow intermediate shield portion between the mating side and the rear side.

15. Connector comprising a shield (1) according to any one of the claims 1-14.