JPS63252135A - Acceleration pulse wave detector - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an acceleroplethysmometer used for health checks in health care rooms, training centers, and the like.

2. Description of the Related Art Conventionally, this type of accelerometer has been used to calculate the peak and valley values (a, b, e, d) of an accelerated pulse wave as shown in Fig. 2, which are obtained by second-order differentiation of the pulse wave. The health condition of the person being measured is determined based on their positional relationship, and this peak,
In order to find the value and position of the valley, the acceleration pulse wave waveform is further differentiated to obtain third-order differentiation to find the peak and valley of the waveform. Based on this value, the characteristics of the waveform are quantified and displayed/recorded. What it does is known.

Problems to be Solved by the Invention In such a conventional configuration, it is necessary to perform the differential operation repeatedly, and if this was attempted to be performed on an electronic circuit, the circuit configuration would be extremely complicated, and the digital Even if one were to try to do this by applying a microcomputer, etc., the problem was that the program software would have to be cumbersome.

The present invention solves these problems by combining waveform data and reference values without performing differentiation operations that may cause troublesome circuit or program problems in order to find peaks and valleys. The aim is to easily find the peak and valley values of seven waveforms and their positions by simple comparison.

Means for Solving the Problem In order to solve this problem, the present invention uses a blood flow pickup that detects the flow of blood in the fingertip or earlobe and second-order differentiation of the pulse wave detected by this blood flow pickup. an accelerated pulse wave converter that converts the pulse wave into an accelerated pulse wave and outputs it as digital data; a memory device including a RAM etc. that stores this digital output as temporal continuous data; and a memory device that stores the numerical data stored in this memory device. a counter that compares with a reference value and detects the number of pieces of data that match the reference value, and sequentially changes the reference value from the maximum value to the minimum value or from the minimum value to the maximum value of the data in the storage device, The acceleroplethysmometer is equipped with an arithmetic unit that calculates the peak and valley values and positions of the waveform of the accelerated pulse wave by storing and calculating the outputs of the counter at each time.

Function: With this configuration, the peak and valley values and positions of accelerated pulse waves, which were conventionally determined using advanced mathematical methods such as third-order differentiation, can also be obtained by simply comparing the waveform data stored in the memory with reference values. It can be found by simply performing simple calculations.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 3. In Figure 1, 1 is a blood flow pickup;
It detects blood flow in the fingertip or earlobe using photoelectric conversion or impedance conversion. 2 is an acceleration pulse wave converter that second-order differentiates the pulse wave detected by the blood flow pickup 1, converts it into an accelerated pulse wave, and outputs it as digital data; 3 is digital data obtained from the accelerated pulse wave converter 2; 4 is a counter, which is a storage device (RAM etc.) that stores the data as temporal continuous data.
The reference value determined by the instruction from the arithmetic unit 5 is compared with the data in the memory 3, and the number of pieces of data that match this is counted and output.

The arithmetic unit 5 digitally sequentially changes the reference value between the maximum value and the minimum value of the data in the storage unit 3, and calculates the output of the counter 4 at each time (the number of pieces of data that match the reference value). ), the presence of peaks and valleys in the accelerated pulse wave waveform is detected, and at the same time, their values and positions are calculated from the data in the memory 3. 6
is a system controller that controls the series of operations described above, calculates the peak and valley values and positional relationships obtained by the calculator 5, calculates an index representing the characteristics of the accelerated pulse wave waveform, and calculates the calculation result. Additionally, the accelerated pulse wave waveform can be displayed on the display 7.

To explain the operation in the above configuration, the pulse wave detected by the blood flow pickup 1 is converted into an accelerated pulse wave in the accelerated pulse wave converter 2, and stored in the form of digital data as a waveform as shown in FIG. 3 is stored. At this time, as explained in the "Prior art" section, a, b, c,
In order to find the value of d and its position, it is necessary to detect the peaks and valleys of the waveform. Therefore, in the present invention, first, the arithmetic unit 5 selects the maximum value among the measured data in the memory 3, and this value is used as the first reference value, ie, Xa in FIG. 3, with which the counter 4 compares. At this time, the output of the counter 4 becomes one point, Put. If the reference value is gradually decreased from this state, the first state will be as shown in XL, and the output of counter 4 at that time will be Pit +
There are two points, Pj2.

When the state of f&X; is reached, the output of counter 4 is changed from the previous two points to P;
Change to a point. This means that a second peak has appeared, and if you select the data that matches Xi from the memory 3, the data will be organized in the memory 3 in chronological order from oldest to oldest. Therefore, the value and position of the peak corresponding to Pu5 can be known.

Follow the same procedure to find the values and positions of the waveform's peaks and valleys one after another.Once you have found all the waveform's peaks and valleys, starting from the beginning, you can By going, a, b in Figure 2,
The values of c and d can be derived. The peak and valley values and positional relationships of the acceleration pulse waveform obtained in this way are arithmetic processed in the system controller 6, and can be obtained as an index indicating the characteristics.
The data within can also be displayed on the display 7 together with the waveform. Although the calculation method of the index is not specifically explained here, many documents have been published in the past on how to read the waveform of this accelerated pulse wave, such as "Pulse Wave Measurement in General Medical Examination": Japan General Medical Examination medical journal,
Vol, 12 No, 4P303 has X= as an index
There are various methods, such as a mathematical formula such as (-b+c+d)/a, and any of them may be used.

Furthermore, in the embodiment, the maximum value of the data in the memory 3 was selected as the starting point for the reference value to be compared, and this value was sequentially decreased, but of course, conversely, starting from the minimum value and increasing sequentially. It doesn't matter how you let it happen.

Effects of the Invention As described above, according to the present invention, the number of matching points can be detected by simply comparing sequentially changing reference values and data without using complicated electronic circuits such as third-order differential or troublesome program software. You can find the values and positions of peaks and valleys that represent the characteristics of the acceleration pulse waveform by simply using the simple method of It has extremely high utility value.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG.
The figure is an explanatory diagram showing detection points necessary for waveform analysis of an accelerated pulse wave, and FIG. 3 is an explanatory diagram showing a method for detecting peaks and valleys according to the present invention. 1...Blood flow pickup, 2...Accelerated pulse wave converter 3...Memory device, 4...Counter, 5...Computer unit Name of agent: Patent attorney Toshio Nakao, 1 person Figure 1 16n Tanenimachi 2'77P, y7'

Claims (1)

[Claims] A blood flow pickup that detects the flow of blood in a fingertip or earlobe, and an acceleration pulse wave converter that takes second-order differentiation of the pulse wave detected by the blood flow pickup, converts it into an accelerated pulse wave, and outputs it as digital data. A memory device such as a RAM that stores this digital output as temporally continuous data, and a counter that compares the numerical data stored in this memory device with a reference value and detects the number of pieces of data that match the reference value. The acceleration pulse is calculated by sequentially changing the reference value from the maximum value to the minimum value or from the minimum value to the maximum value of the data in the storage device, and storing and calculating the output of the counter at each time. An accelerometer that is equipped with a calculator that calculates the peak and valley values and positions of waveforms.