ANTENNA DEVICE

PROBLEM TO BE SOLVED: To provide an antenna device capable of suppressing variation in the inductance value, even if the gap length between two rod-shaped cores varies.SOLUTION: An antenna device includes a first rod-shaped core 20A and a second rod-shaped core 20B arranged in series, and a first coil 30A and a second coil 30B, where the end face 22A of the first rod-shaped core 20A and the end face 22B of the second rod-shaped core 20B are separated, and following formula (1) is satisfied. Formula (1) Dc≥0.3×(CL1+CL2) (In the formula (1), Dc represents the distance (mm) from the end of the first coil 30A to the end of the second coil 30B, CL1 represents the length (mm) of the first rod-shaped core 20A in the medial axis A1 direction, and CL2 represents the length (mm) of the second rod-shaped core 20B in the medial axis A2 direction).SELECTED DRAWING: Figure 2 【課題】２本の棒状コア間のギャップ長さがばらついても、インダクタンス値の変動を抑制できるアンテナ装置を提供すること。【解決手段】直列に配置された第一の棒状コア２０Ａ及び第二の棒状コア２０Ｂと、第一のコイル３０Ａ及び第二のコイル３０Ｂとを備え、第一の棒状コア２０Ａの端面２２Ａと、第二の棒状コア２０Ｂの端面２２Ｂとが離間しており、かつ、下式（１）を満たすアンテナ装置。・式（１） Ｄｃ≧０．３×（ＣＬ１＋ＣＬ２）〔式（１）中、Ｄｃは、第一のコイル３０Ａの端部から、前記第二のコイル３０Ｂの端部までの距離（ｍｍ）を表し、ＣＬ１は、第一の棒状コア２０Ａの中心軸Ａ１方向長さ（ｍｍ）を表し、ＣＬ２は、第二の棒状コア２０Ｂの中心軸Ａ２方向長さ（ｍｍ）を表す。〕【選択図】図２