JPH0415038A - Living body monitoring device - Google Patents

Abstract

PURPOSE:To monitor the body movement such as heart beat, aspiration and turning-over in bed with low cost and without deteriorating the humidity transmissivity and hygroscopicity of the bedclothes by allowing the title living body monitoring device to consist from a flexible piezoelectric element, filter circuit for allowing only the component having a prescribed frequency, amplifying circuit, and a counting circuit. CONSTITUTION:A flexible piezoelectric element 9 is formed by forming a high polymeric piezoelectric material into a thin film form and attaching each flexible electrode film on both the surfaces and shaping this thin film into a tape form, thus the manufacturing cost can be cut, and mass production is permitted, and this film body is fixed on the surface of a mattress 6. When the piezoelectric element 9 is deformed by the body movement such as heart beat, aspiration and turning-over in bed, a voltage is generated by the piezoelectric effect by the piezoelectric element 9. Only the component having the prescribed frequency among the generated voltage outputs is allowed to pass through a filter circuit 10, and after the amplification by an amplifying circuit 11, the body movement such as the number of heart beat, number of aspiration, and the turning-over in bed is counted by counting the number of times in which the output signal of the amplifying circuit becomes over a previously determined threshold value by a counting circuit 12, and the counting value is displayed on a surface part 13.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a living body monitoring device that monitors the heart rate, breathing rate, and body movements such as turning over of a living body on a bed.

BACKGROUND OF THE INVENTION A conventional biological monitoring device of this type will be explained with reference to FIGS. 3 and 4. Note that FIG. 4 shows a cross-sectional view taken along line AA in FIG. 3. As shown in the figure, this biological monitoring device has two antenna members 2a and 2b made of metal plates or metal mesh attached to both sides of an insulating plate 1, and insulating materials 3a and 3b having different insulation constants on the top of the antenna members 2a and 2b. A recording mat 5 formed by overlapping the active layers 3 formed in the above and further covering them with a flexible shield 4 is placed under the pine tress 6, and the antenna members 2a and 2b are connected to the amplifier 7.
It was connected to the recording device 8 via. (For example, Japanese Unexamined Patent Publication No. 55-160539) With the above structure, clothing, bedding, or a mattress 6 can be moved by the heartbeat, breathing, and body movements such as turning over of the person sleeping on the bed 14.
The potential difference caused by the change in electrostatic charge that occurred was amplified and recorded.

Problems to be Solved by the Invention However, with the above structure, the structure of the recording mat 5 is complicated as described above, and the area is as large as that of a pine tress, so the manufacturing cost is high and it is not practical.
Since the recording mat 5 itself does not have moisture permeability or absorbency, there is a problem in that if it is used continuously, moisture accumulates in the pine tress 6 and the like, making it uncomfortable.

The present invention solves these eight problems of the conventional technology.It is possible to reduce heartbeat and moisture absorption at low cost and without impairing the moisture permeability and moisture absorption properties of bedding.
It is an object of the present invention to provide a practical biological monitoring device that monitors body movements such as breathing and turning over in bed.

Means for Solving the Problems In order to solve Problem 1 B, the biological monitoring device of the present invention includes a piezoelectric element having flexibility that can be disposed on bedding such as a futon, a sheet, and a mattress, and the piezoelectric element. a filter circuit that passes only a predetermined frequency component of the output signal;
It consists of an amplifier circuit that amplifies the output signal of the filter circuit, and a counting circuit that counts the output signal of the amplifier circuit.

Operation The present invention operates as follows with the above configuration. In other words, when a piezoelectric element disposed on the bedding is deformed by the heartbeat, breathing, and body movements of the living body on the bedding, such as turning over in bed,
A voltage is generated from the piezoelectric element due to the piezoelectric effect. Then, only a predetermined frequency component of the generated voltage output is passed through a filter circuit, amplified by an amplifier circuit, and then heart rate, breathing rate, and body movements such as turning over in bed are counted by a counting circuit.

Example Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a perspective view of the same embodiment installed on a bed 14, and FIG. 2 is a block diagram of the same embodiment. In the same figure, numeral 9 is a flexible piezoelectric element, and here it is made of a thin film made of a polymeric piezoelectric material such as polyvinylidene fluoride (PVDF) and has flexible electrode films attached to both sides in the form of a tape. The manufacturing cost is relatively low and it can be produced in large quantities. The piezoelectric element 9 is fixed to the surface of the pinerest 6. 10 is a filter circuit that passes only a predetermined frequency component of the output signal of the piezoelectric element 9; 1 is an amplifier circuit that amplifies the output signal of the filter circuit 10; 12 is an amplifier circuit 1;
It is a counting circuit that counts one output signal, and has a display section 13 that displays the counted value.

In the above configuration, when the piezoelectric element 9 disposed on the bedding is deformed by body movements such as heartbeat, breathing, and turning over of the living body on the bedding, a voltage is generated from the piezoelectric element 9 due to the piezoelectric effect. Then, only a predetermined frequency component of the generated voltage output is passed through the filter circuit 10, amplified by the amplifier circuit 11, and then determined by the counting circuit 12 the number of times the output signal of the amplifier circuit exceeds a predetermined dark value. The heart rate, respiratory rate, and body movements such as turning over are counted by dividing , and the counted values are displayed on the display unit 13 .

Here, when counting heart rate, set the band of the filter circuit to about 0.7 to about 2 Hz, and when counting Ill intakes, set the band to about 0.1 to about Q, 5 Hz, and count body movements such as turning over in bed. In this case, it is about 1 to about 101]Z. The band settings for heartbeat and body movement overlap, but since the output signal level is higher for body movement than for heartbeat, the threshold should be set larger when counting body movement than when counting heart rate. be. In addition, when counting heart rate, if body movement occurs, the output signal level is higher for body movement than heartbeat, so the output signal may be disrupted and lead to malfunction, but there is a dark side when counting heart rate. An upper limit value and a lower limit value are set for the value, and the heart rate is counted when the output signal is within the range.

Due to the above action, the piezoelectric element 9 that detects body movements such as heartbeat, breathing, and turning over in bed does not have a complicated structure like the conventional recording mat 5 and has a small shape, so it can be manufactured at a lower cost than the conventional one, and It has the advantage of being able to be easily attached to any type of bed to monitor heart rate, respiratory rate, and body movements such as turning over in bed. Further, even if the piezoelectric element 9 is disposed on the bedclothes, the moisture permeability and moisture absorption properties of the bedclothes are not impaired, so that the mattress does not accumulate moisture and become uncomfortable when used continuously as in the past.

As described above, the biological monitoring device described above can detect heartbeat, breathing, and body movements such as turning over in bed at a low cost and in a practical manner, so it can be used for diagnosis in medical facilities such as hospitals, In addition to being useful for treatment, prevention, and emergency treatment, it can also be useful for home medical care and health management at home, work, etc., which will become increasingly necessary in the future.

In particular, it is expected to make a significant contribution to the early detection and treatment of sudden sleep-related illnesses in which the user is unconscious, such as heart failure, sleep apnea, infant suffocation, and sudden infant death syndrome. Furthermore, body movements during sleep are said to have a correlation with the sleeper's level of sleep, and by counting body movements during sleep, sleep diagnosis, health checks, etc. can be performed. Furthermore, it is said that the number of body movements of infants and young children is correlated with the degree of growth.
By counting the number of body movements, it is also possible to check the degree of growth of infants.

Effects of the Invention As described above, the biological monitoring device of the present invention provides the following effects.

The piezoelectric elements that detect body movements such as heartbeat, breathing, and turning over in bed do not have the complicated structure of conventional devices and are small in size, so they can be manufactured at a lower cost than conventional devices and can be easily attached to any bed. body movements can be detected. In addition, since it does not impair the moisture permeability and moisture absorption properties of bedding,
If you use it continuously like in the past, there is no chance of moisture accumulating in the pine tress and making it uncomfortable.

Also, since the band setting of the filter circuit is set as above, commercial power supply noise (501-(z, 60Hz)
There is no need to worry about contamination.

In this way, heart rate can be detected at low cost and in a practical manner.
Since it is possible to detect body movements such as breathing and turning over in bed, it can be used for diagnosis, treatment, prevention, emergency treatment, etc. at medical facilities such as hospitals, as well as for home medical care, which will become increasingly necessary in the future. It can also be useful for health management at home, work, etc.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a biological monitoring device according to an embodiment of the present invention, Fig. 2 is a block diagram of the same device, Fig. 3 is a sectional view of a conventional biological monitoring device, and Fig. 4 is taken along line AA in Fig. 3. FIG. 9... Piezoelectric element, 10... Filter circuit, 11...
・Amplification circuit, 12... Counting circuit,] 3... Display section,
14... Betsudo. Name of agent: Patent attorney Shigetaka Awano Haka18 No. 1
Figure/4 Δ Pine Torres 13-Exhibition Department Yoi 2I21

Claims (4)

[Claims] (1) A flexible piezoelectric element that can be placed in bedding such as futons, sheets, and mattresses; a filter circuit that passes only a predetermined frequency component of the output signal of the piezoelectric element; and an output of the filter circuit. A biological monitoring device comprising an amplifier circuit that amplifies a signal and a counting circuit that counts the output signal of the amplifier circuit. (2) The biological monitoring device according to claim 1, wherein the filter circuit passes only the frequency component of heartbeat activity in the output signal of the piezoelectric element. (3) The biological monitoring device according to claim 1, wherein the filter circuit passes only the frequency component of respiratory activity in the output signal of the piezoelectric element. (4) The biological monitoring device according to claim 1, wherein the filter circuit passes only a frequency component of body movement such as turning over in the output signal of the piezoelectric element.