BED SENSOR AND BED STATE DETERMINATION DEVICE

PROBLEM TO BE SOLVED: To provide a bed sensor and a bed state determination device at low cost in which malfunction due to change of temperature/humidity and mutual interference is reduced, a non-contact detection distance is extended so as to be installed under a mat spaced apart from a human body, and a care-receiver may carry thereof.SOLUTION: A bed sensor 101 of an electrostatic capacity type is provided for detecting presence or absence of a body B on a bed. The bed sensor comprises a detecting electrode formed of a pair of positive and negative electrodes 1a, 1b, and a reference electrode provided in proximity to the detecting electrode and formed of a pair of positive and negative electrodes 2a, 2b. The bed sensor outputs a detection signal of presence of the body B according to a difference of capacitance by the difference of distance to the body B of the detecting electrode and the reference electrode.SELECTED DRAWING: Figure 3 【課題】本発明は、温度・湿度の変化や相互干渉による誤作動を低減し、人体から離間したマットの下に設置されても良いように非接触検知距離を伸ばし、被看護者が携帯しなくてもよく、安価な離床センサおよび離床状態判定装置を提供することを目的とする。【解決手段】ベッド上の身体Ｂの有無を検出する静電容量式の離床センサ１０１であって、正負一対の電極１ａ、１ｂで形成される検出用電極と、検出用電極に近接して設けられ正負一対の電極２ａ、２ｂで形成される基準用電極と、検出用電極と基準用電極の身体Ｂまでの距離の差による静電容量の差に応じて身体Ｂの存在の検出信号を出力する。【選択図】図３