Patent ID: 7450399
Filing Date: 2008-11-11
Classification: H01P

Abstract:
1. A signal coupling apparatus comprising: a signal coupling element which couples inputted signals and which outputs coupled signal; and a fixing structure which fixes the signal coupling element at a predetermined position on a circuit board including a signal input/output circuit in and from which a predetermined signal is inputted and outputted and signal input/output patterns and grounding patterns for the signal input/output circuit, while the signal coupling element is electrically connected to the signal input/output patterns and grounding patterns, the signal coupling element comprising a slender central electrical conductor which has both end parts providing input and output terminals electrically connected to the signal input/output patterns on the circuit board and an intermediate part between the both end parts, an insulator surrounding the intermediate part of the central conductor concentrically, and an external electrical conductor surrounding an outer peripheral surface of the insulator, and the signal coupling element coupling signals inputted from the input terminals and outputting the coupled signal from the output terminal, and the fixing structure comprising a supporting member which includes an electrically conductive cover part, longitudinal direction facing parts provided integrally with the cover part, and electrically conductive grounding parts provided integrally with both sides of the cover part in a radial direction of the central conductor, and fixing elements which fix the grounding parts of the supporting member to the circuit board, the cover part being in contact with an outer peripheral surface of the external conductor of the signal coupling element and extending over a length of the outer peripheral surface in a longitudinal direction of the central conductor, each facing part facing at least one portion of a peripheral edge of each end surface of the insulator of the signal coupling element in the longitudinal direction of the central conductor, and each grounding part extending in the longitudinal direction of the central conductor and being in contact with each grounding pattern on the circuit board when the signal coupling element is disposed at the predetermined position on the circuit board, and the facing parts preventing the insulator from thermally expanding in the longitudinal direction of the central conductor while the signal coupling element operates.