Electromagnetic shield for an electrical connector

Claim 2

An electromagnetic shield for an electrical connector within a metal shell and having an open end, the shield comprising a first electrically conductive plate (27,35,38) having one or more opening(s) (31) passing therethrough; characterised in that the first plate has its edges fixed to the metal shell (15) and in that a second electrically conductive plate (32,36,40) spaced from the first plate and releasably contacting the metal shell (15), the second plate including opening(s) aligned with the opening(s) in the first plate.

Claim 3

An electromagnetic shield according to claim 1, in which the second plate is spaced from the first plate at a predetermined distance such as to set up cavity resonance between the two plates to incident electromagnetic energy.

Claim 4

An electromagnetic shield according to claim 1 or claim 2 in which the first and second plates are constructed of the same metal as the connector shell.

Claim 5

An electromagnetic shield according to any preceding claim in which the second plate has its edge margins in continuous contact with a generally circular shoulder (33a) on the connector shell.

Claim 6

An electromagnetic shield according to any preceding claim in which the second plate is located outwardly of the first plate and includes spring means resiliently urging the second plate outwardly to a predetermined distance from the first plate.

Claim 7

An electromagnetic shield according to any preceding claim in which the first and second plates are spaced by a predetermined distance defined by the mathematical equation D - φ , where D is the plate spacing, φ is any whole number, and X is the guide wavelength characteristic of the opening(s) (31).

Claim 8

An electromagnetic shield according to any preceding claim in which the surfaces of the plates facing one another inwardly and inwardly directed shell surface between the plates is coated with electromagnetically absorbent material including an insulative carrier within which ferromagnetic particles are suspended.

Claim 9

An electrical connector part (10) having an outer metal shell (15) within which is located one or more electrical contact(s) (25) facing an open end (14) via which complimentary electrical contact(s) (26) from a further connector part (12) are received and including electromagnetic shielding means comprising a first metal plate (29,35,38) integrally formed with the shell (15) and covering the open end (14), the plate having one or more openings (31) aligned with the contact(s) (25); characterised by a second metal plate (32,36,40) removably held at a predetermined spacing from the first plate and having one or more opening(s) (33) aligned with the opening(s) in the first plate, the width of the opening(s) of both plates being sufficient to allow passage with electrical clearance to the complimentary contact(s) (26).

Claim 10

An electrical connector part (10) having an outer metal shell (15) within which is located one or more electrical contact(s) (25) facing an open end (14) via which complimentary electrical contact(s) (26) from a further connector part (12) are received and including electromagnetic shielding means comprising a first metal plate (29,35,38) integrally formed with the shell (15) and covering the open end (14), the plate having one or more openings (31) aligned with the contact(s) (25); characterised by a second metal plate (32,36,40) removably held at a predetermined spacing from the first plate and having one or more opening(s) (33) aligned with the opening(s) in the first plate, the width of the opening(s) of both plates being sufficient to allow passage with electrical clearance to the complimentary contact(s) (26).

Claim 11

An electrical connector part according to claim 8 wherein the electrical contacts (25) are socket contacts for receiving complimentary contacts in the form of pins.

Claim 12

An electrical connector part according to claim 8 or 9 in which the electrical shielding means is as further specified in any of claims 2 to 7.

Claim 13

An electrical connector comprising a connector part (10) according to any of claims 8 to 10 in the form of a receptacle having sockets contacts, and a complimentary connector part (12) in the form of a plug and having pin contacts, and in which the diameter of the openings (31,33) is not less than twice the diameter of the pin contacts.