JPH04256727A - Blood pressure detector - Google Patents

Abstract

PURPOSE:To improve the operability and measurement accuracy at the time of blood pressure measurement by inserting a measuring part consisting of a blood flow detecting element and a pressure sensitive element into the external auditory meatus and measuring the blood pressure. CONSTITUTION:The light from a light emitting diode of the blood flow detecting element 12 falls onto the anterior auricular artery and the reflected light thereof is received by a light receiving element when the measuring part 16 is inserted into the inlet of the external auditory meatus. If there is a change in the blood flow in the anterior auricular artery, this change is outputted as a blood flow signal from the light receiving element. The internal pressure of a cuff 11 is made to follow up the internal pressure of the artery by pressurizing the cuff 11 if there is the blood flow signal of the blood flow detecting element 12 and by reducing the pressure of the cuff 11 if there is no blood flow signal. The internal pressure of the cuff 11 following up the internal pressure of the artery is outputted as the max. blood flow signal by the pressure sensitive element 13.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood pressure detector.

0002

[Prior Art] Conventional blood pressure detectors indirectly measure blood pressure by applying pressure to blood vessels from the outside by attaching a cuff to the upper arm or finger, or to the superficial temporal region or the auricle. are doing. Since these methods apply pressure from the outside, the cuff and the pressure-receiving side are fixed or configured in a cylindrical shape to prevent pressure from escaping in the opposite direction.

However, when detecting with such a conventional detector, the volume and shape of the cuff are large due to the thick subcutaneous tissue and muscles surrounding the artery to be measured, making it difficult to operate when the cuff is attached. This hinders the improvement of sensitivity when detecting blood flow. It also makes continuous measurement over a long period of time difficult.

0004

[Problems to be Solved by the Invention] The present invention improves the operability of detecting blood flow signals and pressure values for indirect blood pressure measurement, and improves the detection sensitivity and accuracy of blood flow signals and pressure values. The purpose is to improve.

[0005]

[Means for Solving the Problems] The present invention has a measuring section that can be freely inserted into the internal auditory canal from the entrance of the external auditory canal, and this measuring section includes a cuff that can pressurize the anterior auricular branch artery; It is characterized by being provided with a detection element that detects blood flow in the anterior auricular branch artery and a pressure-sensitive element that detects the pressure of the cuff.

[0006]

[Operation] The measurement site is set near the entrance of the external auditory canal, and the measuring section consisting of a cuff, a blood flow detection element, and a pressure sensitive element is inserted into the entrance of the external auditory canal. Since the cuff pressurizes the artery along the wall of the external auditory canal, little pressure component escapes outside the cuff. Furthermore, in this region, there is only a small amount of subcutaneous tissue around the artery, so the detection sensitivity of blood flow signals is extremely high, and the pressurizing effect of the cuff is also good. Therefore, the cuff can be constructed with a small volume. Furthermore, since the measuring section is inserted into the external auditory canal for measurement, no particular holding mechanism is required for the measuring section and thus the detector.

[0007]

[Embodiment] An embodiment of the present invention will be explained with reference to the drawings. 1 is the ear helix, 2 is the blood pressure detector according to the present invention, 3 is the ear lobe, 4 is the entrance of the external auditory canal, 5 is the external auditory canal, 6 is the anterior auricular branch artery, 7 is the cartilage,
8 is a ventilation hole, 9 is an insertion guide, 10 is a case, and 11 is a cuff, which is formed into a cylindrical shape and is translucent.

Reference numeral 12 denotes a blood flow detection element, which is composed of a light emitting diode 19 serving as a light source and a light receiving element 20. 13 is a pressure sensitive element, 14 is a pressure generating section, which is composed of a micro motor 17 and a pump 18. 15
Reference numeral denotes a pressure control section, which is composed of an amplification section 21, a pressure increase/decrease discrimination section 22, and a motor drive section 23. 16 is a measuring section.

When the measuring section 16 is inserted into the external auditory canal entrance 4,
The light from the light emitting diode 19 of the blood flow detection element 12 illuminates the anterior auricular branch artery 6, and the reflected light is received by the light receiving element 20.

At this time, if there is a change in blood flow in the anterior auricular branch artery 6 (due to a change in blood pressure), the light receiving element 20 outputs a blood flow signal. This blood flow signal is amplified by the amplifying section 21 and output as a pulse output, and is also sent to the pressurization/depression discriminating section 22 .

[0011] When the blood flow signal is present, the pressurization/depressurization discrimination section 22 controls the micromotor 17 via the motor drive section 23 .
is rotated in the normal direction to pressurize the cuff 11 with the pump 18. When the cuff 11 is sequentially pressurized and the cuff pressure becomes higher than the internal pressure of the anterior auricular branch artery 6 where the blood pressure is measured by the cuff 11, the blood flow signal from the blood flow detection element 12 disappears.

When the blood flow signal from the blood flow detection element 12 disappears, the pressure adjustment/depression discrimination section 22 reverses the micromotor 17 via the motor drive section 23 and causes the pump 18 to pump the cuff 1.
Depressurize 1. When the cuff 11 is depressurized and the cuff pressure becomes lower than the internal pressure of the anterior auricular branch artery 6, the blood flow detection element 12 outputs a blood flow signal again.

As described above, by pressurizing the cuff 11 when there is a blood flow signal from the blood flow detection element 12 and depressurizing the cuff 11 when there is no blood flow signal, the internal pressure of the cuff 11 can be adjusted to
Follows arterial pressure. The pressure sensing element 13 outputs the internal pressure of the cuff 11, which follows the arterial internal pressure, as a systolic blood pressure signal.

In the example shown in the figure, the pressure generating section 14 and the pressure controlling section 15 are provided integrally within the case 10, but instead of this, they can be separated from the case 10 and attached to the back of the auricle. You may also do so.

[0015]

[Effects of the Invention] As explained above, according to the present invention, blood pressure is measured by inserting the measuring section into the external auditory canal, so that the burden on the living body due to wearing the detector is extremely small.
Unlike conventional detectors, there is almost no sense of restraint or tension on the subject, and it also provides high stability and high precision performance even during continuous measurements over a long period of time.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the present invention, and is a front view with the left half in section.

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a block diagram inside the detector.

FIG. 4 is a partial sectional view showing the state of use.

[Explanation of symbols]

11 Cuff 12 Blood flow detection element 13 Pressure sensitive element 16 Measurement part 19 Light source 20 Photo receiving element

Claims (1)

[Claims] 1. A measuring part that can be inserted into the inside of the external auditory canal from the entrance of the external auditory canal, and the measuring part has a cylindrical shape and can be expanded outwardly by applying pressure. A blood flow detection element comprising a cuff, a light source that irradiates light onto a blood pressure measurement site by the cuff, and a light receiving element that receives reflected light from the blood pressure measurement site, and a pressure sensitive element that detects the pressure of the cuff. Blood pressure detector provided.