Patent ID: 8454521
Filing Date: 2013-06-04
Classification: A61B

Abstract:
1. A sphygmomanometer, that measures blood pressure in accordance with an oscillation in an artery wall, resulting from an arterial pulse correspondent with a change in cuff pressure, comprising: a cuff that is connected to a sphygmomanometer main body by a tube; an air supply unit for supplying air to and pressurizing the cuff, the air supply unit being detachable from the sphygmomanometer main body, and forming a single unit when attached to the sphygmomanometer main body; a mode switch for selecting a measurement mode from among a Normal mode that measures blood pressure automatically, a Slow mode that measures blood pressure automatically, and a Stethoscope mode for measuring blood pressure manually via a stethoscope; a control unit for controlling opening and closing of an electromagnetic valve of the sphygmomanometer to adjust a speed at which air is exhausted from the cuff according to the measurement mode selected via the mode switch so that the control unit controls the electromagnetic valve to: i) keep the exhaust speed at a first preset exhaust speed during blood pressure measurement when the Normal mode is selected by the mode switch; ii) keep the exhaust speed at a second preset exhaust speed during blood pressure measurement when the Slow mode is selected by the mode switch, the second preset exhaust speed being approximately half of the first preset exhaust speed; and iii) keep the exhaust speed at a third preset exhaust speed during blood pressure measurement when the Stethoscope mode is selected by the mode switch, the third preset exhaust speed being approximately the same as the second preset exhaust speed; a display unit which displays a blood pressure measurement result and the selected measurement mode, a pressure sensor measuring a pressure of the cuff, and a memory storing pressure values measured by the pressure sensor during depressurization of the cuff, wherein the control unit determines a systolic blood pressure based on the stored pressure values, identifies a first pressure value from amongst the stored pressure values at which the amplitude dramatically increases for a first time and also identifies a second pressure value from amongst the stored pressure values at which the amplitude dramatically decreases for a first time as seen from a point of maximum amplitude of the pressure, the control unit obtains the first pressure value at which the amplitude dramatically increases for a first time as a first systolic blood pressure candidate value, the control unit obtains the second pressure value at which the amplitude dramatically decreases for a first time as seen from a point of maximum amplitude of the pressure as a second systolic blood pressure candidate value, the control unit determines whether a difference between the first systolic blood pressure candidate value and the second systolic blood pressure candidate value is within a prescribed value, and the control unit determines a blood pressure corresponding to the first systolic blood pressure candidate value as the systolic blood pressure when the difference between the first systolic blood pressure candidate value and the second systolic blood pressure candidate value is within a prescribed value.