PROBLEM TO BE SOLVED: To provide an automatic blood pressure measuring apparatus capable of obtaining accurate pulse waves by appropriately applying a compression pressure to an artery inside a part to be compressed and obtaining a highly accurate highest blood pressure value on the basis of the pulse waves.SOLUTION: A pressure band 12 includes expansion bags 22, 24 and 26 which are connected in the width direction and provided with independent air chambers for respectively compressing an upper arm 10. By successively calculating an amplitude ratio r23 which is a value in which the amplitude value A2 of pulse wave signals SM2 from the intermediate expansion bag 24 positioned more on the upstream side than the downstream side expansion bag 26 is divided by the amplitude value A3 of pulse wave signals SM3 from the downstream side expansion bag 26 positioned on the downstream side of the artery 16 inside the upper arm 10 among the expansion bags, and determining the highest blood pressure value SBP of a living body on the basis of the amplitude ratio r23, the accurate pulse wave signals SM are obtained by applying the compression pressure to the artery 16 in an equal pressure distribution from the respective expansion bags turned to the state of being independent of each other regarding a pressure fluctuation, and thus the highly accurate highest blood pressure value SBP is obtained.COPYRIGHT: (C)2012,JPO&INPIT【課題】被圧迫部位内の動脈に圧迫圧力を適正に加えることで正確な脈波が得られ、その脈波に基づいて精度の高い最高血圧値が得られる自動血圧測定装置を提供する。【解決手段】圧迫帯12は幅方向に連ねられて上腕10を各々圧迫する独立した気室を有する膨張袋22、24、26を有するものであり、それら膨張袋のうちの上腕10内の動脈16の下流側に位置する下流側膨張袋26からの脈波信号SM3の振幅値A3で、その下流側膨張袋26よりも上流側に位置する中間膨張袋24からの脈波信号SM2の振幅値A2を除した値である振幅比r23を逐次算出し、その振幅比r23に基づいて生体の最高血圧値SBPを決定することから、相互間が圧力変動に関して独立状態とされた各膨張袋から動脈16に圧迫圧力を均等な圧力分布で加えることで正確な脈波信号SMが得られるので、精度の高い最高血圧値SBPが得られる。【選択図】図5
