The bed provided with the back raising mechanism includes a support member that supports the back portion of the bed from a direction corresponding to a back raising angle, and a sensor attached to the support member. Alternatively, in a bed having a back raising mechanism, a sensor attached to any member forming the back portion is provided in a back portion in which an angle formed with the floor surface varies according to adjustment of the back raising angle.背上げ機構を備えたベッドにおいて、背上げ角に応じた方向から前記ベッドの背部を支持する支持部材と、前記支持部材に取り付けられたセンサとを備える。或いは、背上げ機構を備えたベッドにおいて、背上げ角の調整に応じて床面とのなす角が変動する背部において、前記背部を形成するいずれかの部材に取り付けられたセンサを備える。
