Retaining clip

A retaining clip is for securing an electrical connector to be inserted through an opening formed in a panel. The retaining clip comprises a base having an aperture therethrough for receiving the free end of the electrical connector and having one or more engagement means for engaging with and holding the electrical connector. The base is shaped to contact at least a portion of the surface of the panel that it overlies. A plurality of fingers extending away from the base are displaceable to allow insertion of a mating connector and to contact the surface of the mating connector. Thus, the clip shields the surface of the mating connector with respect to the panel.

This application claims priority to prior UK patent application No. 0319033.7, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to retaining clips and in particular to retaining clips used to secure devices such as electrical connectors mounted through an aperture in the casing of a computer including servers or other electronic device.

In order to hold electrical connectors, such as data connectors, in position in an aperture in the casing of a computer it is well known to use pairs of c-shaped clips that abut the surface of the casing and engage either end of that portion of the electrical connector that projects beyond the aperture. U.S. Pat. No. 6,513,206 describes an alternative retaining clip which is illustrated in combination with a conventional electrical connector inFIG. 1. The retaining clip comprises a single planar element1having an aperture2for receiving the free end of an electrical connector3and locking tabs4,5. The locking tabs4,5are arranged to engage with detent surfaces provided on the electrical connector by means of a sliding movement in the direction of arrow A.

SUMMARY OF THE INVENTION

The present invention seeks to provide an improvement on known retaining clips and in particular to provide retaining clips that contribute to the shielding of the electronic device of which the connector forms a part.

In accordance with the present invention there is provided a retaining clip for securing an electrical connector to be inserted through an opening formed in a panel, the retaining clip comprising a base having an aperture therethrough for receiving the free end of the electrical connector and having one or more engagement means for engaging with and holding the electrical connector, the base being shaped to contact at least a portion of the surface of the panel that it overlies; and a plurality of fingers extending away from the base being displaceable to allow insertion of a mating connector and to contact the surface of the mating connector whereby the clip shields the surface of the mating connector with respect to the panel.

Thus with the present invention the retaining clip provides the additional function of em shielding.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown inFIGS. 2–4the retaining clip10comprises a base11having an opening or aperture12shaped to receive the free end of an electrical connector. The base11is intended to contact at least a portion of the outer surface of the casing for an electronic device such as a computer which the base overlies, and to ground the clip with respect to the casing. Hence, where the panel of the casing is planar the base is similarly planar. Engagement means in the form of a pair of locking tabs13,14, that are preferably integral with the base11, partially project across one end of the aperture12. The locking tabs13,14are shaped to engage detents provided on conventional electrical connectors. Engagement of the locking tabs13,14with the detents on the electrical connector is by means of a sideways movement of the retaining clip10with respect to the electrical connector.

Extending upwardly from the base11are a plurality of resilient fingers15which form the walls of a cage shaped to receive the free end of a conventional electrical connector. Each finger15, which is separated from its neighbor by a narrow slot16, consists of first and second portions17,18. The first portion17extends substantially perpendicular to the base11whereas the second portion18describes an arc which, in a direction from the first portion17to its free end, firstly curves into the region above the aperture12and then away from that region. Thus, the curved surface of each arc portion18acts as a contacting surface to the free end of the electrical connector. The fingers15extend along both long sides of the clip and across each end of the clip. Inclusion of fingers at the short ends of the retaining clip is deemed optional.

Each of the fingers15is movable so as to allow passage of the electrical connector whilst also forming contact with the surface of the connector. Preferably the fingers are biased towards the volume immediately above the aperture12but are sufficiently resilient that on contacting the electrical connector, the individual fingers are capable of outward flexure to permit the passage of the connector. As a result of the arc portion18of each finger, though, the fingers retain contact with the electrical connector as it is inserted through the aperture12and are capable of maintaining contact even over the surface of an irregularly shaped connector once the connector is locked in position. The width of each finger15and its length are selected in dependent upon the contact force to be applied by the finger to the electrical connector. The fingers15of the retaining clip10act to ground the electrical connector across a wide area and, as the base11is on contact with the casing to the electronic device, the retaining clip acts to ground the electrical connector with respect to the casing. Thus, the fingers15function as em shielding to prevent the escape of electromagnetic radiation from the electronic device of which the electrical connector forms a part and to shield against external electromagnetic radiation.

The performance of two retaining clips10in providing em shielding has been tested using a standard emc chamber and the following are results that were obtained.

Margin with respect to Class A (dB) for selected frequencies (MHz)Peak measurements in bold, quasi-peak measurements in bracketsRetainingclip656700756984131019702620328036104590Testcase17201714(11)239131212131Testcase1713(10)10(6)14(10)157109.59.59.52

InFIGS. 5–7an alternative version of the retaining clip is illustrated. This alternative version of the retaining clip is very similar to the retaining clip ofFIGS. 2–4and like reference numerals have been primed to indicate like features. The main difference between the two versions of the retaining clip is the inclusion of a plurality of slots19′ cut into the base11′ each of which extends into the first portion17′ of a respective one of the resilient fingers15′. These slots interrupt what is a continuous base in the first version of the retaining clip10. Thus, in this alternative version, the base11′ comprises a plurality of separate segments surrounding the aperture12′ with the fingers15′ acting as bridging elements to hold the separate segments of the base11′ together.

For both versions of the retaining clip described above, the clip10is preferably fabricated from a single metallic sheet that is cut by punching using a press and folded into the desired shape. This simplicity of construction greatly contributes to minimising the costs of fabrication.

Referring toFIGS. 8 to 10, a further alternative version of the retaining clip will be described. The further alternative version of the retaining clip is similar to the retaining clip ofFIGS. 2–4and like reference numerals have been primed to indicate like features. The difference between the two versions will be described hereinafter.

In the first embodiment, each finger15is separated from its neighbor by a narrow slot16. On the other hand, each of resiliently deformable flat plates15″ extending from opposite short sides of a base11″ in this version has no slot, as shown inFIG. 8. Therefore, each flat plate15″ is less resilient than each finger15in the first embodiment and is not easily deformable as compared with each finger15in the first embodiment.

Mechanical relationship among a retaining clip10″, a plug connector21, and a panel31in this version will be described with reference toFIGS. 9 and 10.

The retaining clip10″ is fitted into an aperture32of the panel31as shown inFIG. 9. InFIG. 9, the plug connector21is not yet inserted into the retaining clip10″.

InFIG. 10, the plug connector21is inserted into the retaining clip10″.

In this state, the plug connector21applies forces F1, F2to each flat plate15″ in the direction of arrows, respectively. Then, forces F3, F4, F5, F6are produced at four points A, B, C, D of the retaining clip10″ in the direction of arrows, respectively. F3, F4are forces exerted by the retaining clip10″ to push the panel31. F5, F6are forces exerted by the retaining clip10″ to push the plug connector21. Under the forces F1, F2, F3, F4, F5, and F6, the plug connector21, the retaining clip10″, the panel31, and a receptacle connector41are electrically connected and grounded.

Referring toFIGS. 11 and 12, the structure of fitting the retaining clip10will be described in detail.

InFIG. 12, a shield cover42is attached to the receptacle connector41from the upper surface of the receptacle connector41. A gasket43is fitted to the receptacle connector41from the front surface of the receptacle connector41. Thereafter, the receptacle connector41is inserted into the aperture32of the panel31from the rear surface of the panel31and the retaining clip10is inserted into the aperture32from the front surface of the panel31. In the state shown inFIG. 11, the plug connector21is inserted into the retaining clip10.

The retaining clips in accordance with the invention thus provide both a locking mechanism for holding an electrical connector in place when inserted through an aperture in the casing of an electronic device such as a computer and also provides em shielding by grounding a wide surface area of the electrical connector to the outer surface of the casing.

Changes to the retaining clips described above are envisaged without departing from the present invention which is limited in scope by the accompanying claims only.