JP3021886B2 - Constant heart rate monitoring system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a constant heart rate monitoring system which constantly monitors the heart rate of a person to be monitored, and detects abnormalities in the heart rate and informs the user accordingly.

[0002]

2. Description of the Related Art A conventional continuous heart rate monitoring system is not completely unhealthy, but is always carried by people who have a shallow degree of heart disease and need to constantly monitor their heart rate. If the heart rate is abnormal, the emergency signal is immediately transmitted from the carrying transmitter to the receiver connected to the telephone, for example, and the emergency signal is sent to the centralized management system installed in the hospital. It is to report.

[0003]

Although the transmitter is limited in size in terms of portability, the transmitter always determines an abnormal heart rate and transmits an emergency signal as necessary. Power consumption,
Since the life of the battery serving as the power supply is short, the battery must be frequently replaced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a transmitter which is always carried by a person to be monitored and which determines an abnormal heart rate and transmits an emergency signal. It is an object of the present invention to provide a constant heart rate monitoring system capable of reducing the power consumption of a battery and extending the life of a battery serving as a power source thereof.

[0005]

That is, the present invention provides a receiving section for receiving a heartbeat signal transmitted from a heartbeat detector directly attached to the body of a person to be monitored, and a receiving section for receiving the heartbeat signal. An emergency signal is sent to an abnormality judging unit that judges an abnormal heartbeat of the monitored person based on the heartbeat signal, and a receiver that performs a notification process when a heartbeat abnormality occurs when the abnormal judgment unit judges that the monitored object person has an abnormal heartbeat. A transmitting unit having a transmitting unit for transmitting the heartbeat signal, the computing unit predicting and calculating the reception timing of the next heartbeat signal received by the receiving unit, and the first timing is calculated based on the reception timing obtained by the computing unit.
It is determined whether or not the receiving unit has received the heartbeat signal, and if the heartbeat signal is continuously received a predetermined number of times at the predicted reception timing, the energization of the drive to the first receiving unit is performed by the arithmetic unit. When the heart rate signal is not received at the reception timing predicted during this power saving mode, the drive power supply to the first receiving unit is immediately performed. The mode is controlled so as to shift to the normal mode in which the heart rate is constantly changed.When the heart rate is determined to be stable, the mode automatically shifts to the power saving mode, and it is predicted that the next heart rate signal will be received. Until a certain timing, the operation of the receiving unit is stopped, so that useless power consumption can be suppressed.

[0006]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a basic external structure according to an embodiment of the present invention. In FIG. 1, 1 is a portion directly detectable on the body of the monitored person, for example, directly below the left chest. A detector 2 is attached and transmits a detected heartbeat signal by electromagnetic induction (indicated as “EM” in the figure). A detector 2 is attached to, for example, the left wrist of the monitored subject, and a heartbeat signal by electromagnetic induction from the detector 1 is provided. Received, the heart rate is displayed, the heart rate signal is corrected for errors and stabilized, and then the heart rate is judged to be abnormal. If there is an abnormality, an emergency signal indicating that an abnormality has occurred is transmitted to the carrier frequency (FIG. Then, "R
F), which is superimposed on and transmitted by radio, 3 is connected to, for example, a telephone 4 and one or more transmitters 2
This is a receiver that receives an abnormality occurrence signal superimposed on the carrier frequency sent from the device, and energizes and informs doctors and nurses, and implements the present invention by using these detector 1, transmitter 2 and receiver 3. A constant heart rate monitoring system according to the example is configured.

FIG. 2 shows a state in which the detector 1 and the transmitter 2 are mounted on the person 5 to be monitored. As shown in the figure, the detector 1 is fixedly attached to the lower left chest, which is a part where the heartbeat can be reliably detected on the body of the monitoring subject 5 by the band 6 or the like, and protrudes from the surface thereof. A pair of electrodes contact the skin immediately above the heart.
The heartbeat detected by the detector 1 is converted into a signal and transmitted by electromagnetic induction within an effective range of, for example, 70 to 80 cm. The signal by the electromagnetic induction is attached to the left wrist of the subject 5 to be monitored. It is received by the transmitter 2 in the form of a wristwatch.

The transmitter 2 performs noise removal and interpolation error correction on the received heartbeat signal due to electromagnetic induction,
Thereafter, the heart rate is calculated, and the presence or absence of an abnormality such as arrhythmia is determined.If there is an abnormality, an emergency signal indicating that the abnormality has occurred to a receiver 3 not shown is superimposed on the carrier frequency and wirelessly transmitted. I do. Next, specific circuit configurations of the detector 1 and the transmitter 2 will be described.

FIG. 3 shows a configuration of an electronic circuit provided in the detector 1. In the figure, reference numeral 11 denotes a heartbeat detection unit, which amplifies and filters a myoelectric potential difference of a human body obtained from the pair of electrodes abutted on a corresponding part of the monitored subject 5, generates a heartbeat signal a, and transmits the EM signal. Output to the control unit 12.

The EM transmission control unit 12 has an oscillation circuit inside.
12a, a capacitor 13 and a resistor 14 are connected in series externally, and the noise removal and interpolation error correction are performed on the heartbeat signal a from the heartbeat detection unit 11, and the resistance 15 is used as the heartbeat signal b. To the base electrode of the NPN transistor 16

A capacitor 17 is connected between the collector electrode and the emitter electrode of the transistor 16, the collector electrode is connected to one end of an electromagnetic induction coil 18, and the emitter electrode is connected to the EM transmission controller 12. . The voltage VCC is applied to the other end of the electromagnetic induction coil 18 and one end of the capacitor 20 via the resistor 19, and the other end of the capacitor 20 is connected to the emitter electrode of the transistor 16.

FIG. 4 shows a circuit configuration inside the transmitter 2. In the figure, the electromagnetic induction by the electromagnetic induction coil 18 of the detector 1 is received by the EM receiving unit 31 by selecting the frequency by the electromagnetic induction coil 32 connected in parallel with the capacitor 33,
The pulse signal is converted into a pulse signal by the receiving unit 31 and is used as a heartbeat signal c by the CPU
Sent to 34.

The CPU 34 controls the operation of each circuit in the transmitter 2 based on the heartbeat signal c from the EM receiving unit 31, and calculates the heart rate and predicts the reception timing of the next heartbeat signal c. Arithmetic unit 35, timing unit that performs timing operation
36, Flag register for holding operation mode status
37, a heart rate register (shown as "HR" in the figure) 38 for holding heart rate data, a register section 39 for holding various control data, and a time and heart rate display on a display section 40 comprising a liquid crystal display element. The display data such as the number is output to the RF transmitter 41 as an emergency signal.

The flag register 37 is a normal mode flag register (shown as "N" in the figure) for setting a flag "1" in a normal mode in which the EM receiving section 31 always performs a receiving operation. A rest mode flag register (indicated as “R” in the figure) that sets a flag “1” in a “rest mode” in which the reception operation of the EM receiving unit 31 is stopped until it is predicted to be received, A sleep mode flag register (shown as "S" in the figure) which sets a flag "1" in a sleep mode in which reception is performed intermittently and the reception operation of the EM receiver 31 is stopped during that time. By recognizing the set state of each flag of the flag register section 37,
The PU 34 stops sending the operation signal d to the EM receiver 31 as necessary, and temporarily stops the operation.

The register unit 39 includes an x register 39a for determining whether the heart rate is stable, a t register 39b for holding a reception interval of the heart rate signal c, and a time when the heart rate signal c is received this time. And a tf register 39d for holding a predicted reception time of the next heartbeat signal c calculated by calculation.

Although not shown, the heart rate register 38 has a multi-stage configuration using a FIFO type register.
A large number of the most recently obtained heart rate data, for example, 10
Are held continuously.

The tn register in the register section 39
39c has a two-stage configuration, not shown, and includes the present reception time data "tn" and the previous reception time data "tn-1".
Can be stored. The RF transmission unit 40 is a CPU
The emergency signal transmitted from 34 is superimposed on the carrier frequency and transmitted to the receiver 3 (not shown). Next, the operation of the above embodiment will be described.

FIG. 5 shows the above "normal mode" and "rest mode".
And a “sleep mode”.
As shown in the figure, when the "normal mode" in which the reception is always performed is executed, if a constant heart rate is continuously obtained n times during the reception, the mode shifts to the "rest mode".

This "rest mode" is based on the assumption that the monitored subject 5 is in a non-exercising state. The next timing at which a heartbeat signal is received is predicted by calculation, and after the heartbeat signal is received, the next heartbeat signal is received. Until the expected time that will be received,
The operation of the EM receiver 31 is stopped. And
If a constant heart rate is further obtained m times continuously in the "rest mode", the process proceeds to the "sleep mode".

This "sleep mode" is based on the assumption that the monitored subject 5 is in a sleeping state. If the monitored subject 5 has a heart disease, the "sleep mode" is not adopted depending on the application and the transition to the "sleep mode" is performed. It may be prohibited. Thus, in the "sleep mode", the operation in the "rest mode" and the state in which the EM receiver 31 is completely stopped are repeatedly executed, for example, every several minutes.

The above-mentioned "rest mode" and "sleep mode"
In any case, if the heart rate signal c cannot be received at the predicted timing or if it is determined that the heart rate fluctuates greatly, the mode immediately returns to the “normal mode”. . Next, reception processing of the heartbeat signal c by the CPU 34 in each of the “rest mode” and the “sleep mode” will be described.

FIG. 6 shows the EM receiver in the "rest mode".
This shows the content of the reception processing of the heartbeat signal c from the base station 31. When the heartbeat signal c is received from the EM receiver 31, the CPU 34
First, as shown in step A1, the time data at the time of receiving the heartbeat signal c is fetched from the timer section 36, and this is stored in the tn register 39c of the register section 39 at the current reception time "t
n ”.

Next, at step A2, the CPU 34
It is determined whether the current reception time "tn" held in the n register 39c is equal to the predicted time held in the tf register 39d during the previous reception processing. In this case, the CPU 34
Is the heart rate variability allowable value (tm, not shown) stored inside.
], If the current reception time "tn" held in the tn register 39c is within the range of "tm" before and after the prediction time held in the tf register 39d, it is determined that the time is the prediction time. In step A3, the receiving operation of the heartbeat signal c by the EM receiving unit 31 is temporarily stopped.

FIG. 8 shows the "normal mode" to the "rest mode".
Shows the reception stop state immediately after the transition to. As shown in the figure, assuming that the CPU 34 has received the heartbeat signal c stably at the time interval “T” until then, even when shifting to the “rest mode”, the CPU 34 starts from the time when the pulse of the heartbeat signal c is received. During the period of time "T-tm", the operation signal d to the EM receiver 31 is stopped to temporarily stop the operation.

The stop process is executed and the CPU 34
As shown in step A4, the previous reception time data "tn-1" is subtracted from the current reception time data "tn" held in the tn register 39c by the computing unit 35, and the difference is calculated as a new time interval. The data is held in the t register 39b.

Thereafter, the CPU 34 causes the calculation unit 35 to execute the calculation "60 / T" using the reception interval data held in the t register 39b as a divisor in step A5 and using a constant "60 (seconds)". The heart rate register 38 holds the heart rate data "HRn" corresponding to the current one-minute heart rate.

Then, in step A6, the x register 39a for determining whether or not the heart rate is stable is updated and set to "+1", and in step A7, the updated x register is set.
It is determined whether or not the content of 39a has become the constant "m" held in the CPU 34.

If it is determined that the constant "m" has not yet been reached, then, at step A8, the ten most recent consecutive heart rate data "HRn" held in the heart rate register 38.
HRn-9 "and the current reception time data" tn "held in the tn register 39c, the calculation unit 35 calculates the predicted time at which the next heartbeat signal c will be received, and stores this in the tf register 39d. . After that, in step A9, the process waits until the pulse of the next heartbeat signal c is actually received, and when it is determined that there is a pulse, the process from step A1 is repeated again.

In step A2, there is no current reception time "tn" held in the tn register 39c within the range of "tm" before and after the prediction time held in the tf register 39d in step A2. If the CPU 34 determines that the received signal is out of the range, the CPU 34 next proceeds to step A10 where the x register is received.
Clear the contents of 39a to "0", and continue to step A1
When the flag is set to 1, a new flag "1" is set in the normal mode flag register of the flag register section 37, and "0" is set in the same quiet mode flag register in place of the previous flag "1", and then the "normal mode" is set. To the reception processing state.

Further, x updated and set in step A7 is used.
When determining that the content of the register 39a has become the constant "m" held in the CPU 34, the CPU 34 then clears the content of the x register 39a to "0" in step A12, and then proceeds to step A13 to reset the flag register unit. 37
A new flag “1” in the sleep mode flag register of
The previous flag “1” is stored in the resting mode flag register.
Is set to "0" in place of, and then the mode shifts to the "sleeping mode" reception processing state.

FIG. 7 shows the contents of the processing of receiving the heartbeat signal c from the EM receiver 31 in the "sleep mode". When the heart rate signal c is received from the EM receiver 31, the CPU
First, as shown in step B1, the time data at the time when the heartbeat signal c is received is fetched from the timer section 36, and the time data is stored in the tn register 39c of the register section 39 at the current reception time "t".
n ”.

Next, in step B2, the CPU 34 determines whether or not the reception of the heartbeat signal c is the first one after the "sleep mode" has been received, based on whether or not the content of the x register 39a is "0". I do.

When the content of the x register 39a is "0", the CPU 34 decides to postpone the processing relating to the predicted time for the reception of the current heartbeat signal c in order to measure the stability of the operation. After the content of the register 39a is updated to "+1" and set to "1", the process waits until a pulse of the heartbeat signal c is received in step B13, and if it is determined that there is a pulse, the process from step B1 is repeated again. Execute.

When the heartbeat signal c is shifted for the second time after entering the "sleep mode", the time data at the time when the heartbeat signal c is received in step B1 is stored in the tn register 39c in the current reception time "tn". "In step B2.
After determining that the content of the x register 39a is not "0", the current reception time "tn" held in the tn register 39c in step B3 and the estimated time held in the previous reception processing in the tf register 39d It is determined whether or not are equal. If it is determined that the time is the predicted time, the CPU 34 temporarily stops the operation of receiving the heartbeat signal c by the EM receiving unit 31 in step B4.

FIG. 9 shows a transition from the "rest mode" to the "sleep mode".
Shows the reception stop state immediately after the transition to. As shown in the figure, the CPU 34 has been performing the receiving operation in the EM receiving unit 31 by the operation signal d only in a specific time period in which the heartbeat signal c is predicted to be received in the “rest mode” until then. Even after the transition to the "sleep mode", the operation of the "rest mode" is continued only once for the first time, and thereafter, the EM receiving unit 31 continues for a predetermined time, for example, while receiving two pulses of the heartbeat signal c. The operation signal d is continuously stopped to stop the operation, and thereafter, the operation stop state and the operation in the “rest mode” are repeatedly executed for every two pulses of the heartbeat signal c.

The stop processing in step B4 is executed, and the CPU 34 sets the tn register as shown in step B5.
The arithmetic unit 35 subtracts the previous reception time data "tn-1" from the current reception time data "tn" held in 39c, and uses the difference as new time interval data in the t register 39.
b.

Thereafter, the CPU 34 causes the calculation unit 35 to execute the calculation "60 / T" using the reception interval data held in the t register 39b in step B6 as a divisor and using a constant "60 (seconds)". The heart rate register 38 holds the heart rate data "HRn" corresponding to the current one-minute heart rate.

Next, the CPU 34 stores the current heart rate data "HRn" held in the heart rate register 38 in step B7.
And the absolute value of the difference between the previous data "HRn-1" and "|
HRn-HRn-1 | "is calculated by the computing unit 35, and in the following step B8, it is determined whether or not the heart rate fluctuation is severe depending on whether the calculated value is larger or smaller than a predetermined value.

If it is determined that the heart rate is small, it is determined that there is no abnormality in the heart rate at that time. Then, the process proceeds to step B9, where the latest ten consecutive heart rate data "HRn to HRn-" held in the heart rate register 38 are stored. 9 "and the tn register
Based on the current reception time data "tn" held in 39c, the calculation unit 35 calculates a predicted time at which the next heartbeat signal c will be received, and stores this in the tf register 39d. After that, in step B10, the process waits until the pulse of the next heartbeat signal c is actually received, and if it is determined that there is a pulse, the process from step B1 is repeated again.

Further, for example, because the monitored person 5 wakes up from a state of sleeping, the above-described step B is performed.
If it is determined in step 3 that the heartbeat signal c has been received outside the predicted time, or if it is determined in step B8 that the heart rate has fluctuated greatly, the CPU 34 proceeds to step B11.
Then, a new flag "1" is set in the normal mode flag register of the flag register unit 37, and "0" is set in the sleeping mode flag register in place of the previous flag "1". Return to the reception processing state.

As described above, by shifting from the “normal mode” to the “rest mode” and from the “rest mode” to the “sleep mode”, the CPU 34 sequentially transmits the EM receiving unit 31.
The operation state is gradually stopped by the operation signal d to suppress unnecessary power consumption in the EM receiving unit 31 in the reception standby state, so that the battery which is the power supply of the transmitter 2 is used effectively. Can be.

[0043]

As described above in detail, according to the present invention, a receiving section for receiving a heart rate signal transmitted from a heart rate detector directly attached to the body of a person to be monitored, and a receiving section for receiving the heart rate signal. An emergency signal is sent to an abnormality judging unit that judges an abnormal heartbeat of the monitored person based on the heartbeat signal, and a receiver that performs a notification process when a heartbeat abnormality occurs when the abnormal judgment unit judges that the monitored object person has an abnormal heartbeat. In a transmission unit having a transmission unit for transmitting, a calculation unit for predicting and calculating the reception timing of the next heartbeat signal received by the reception unit is provided, and the reception unit obtains the first reception unit with the reception timing obtained by the calculation unit. It is determined whether or not the heartbeat signal has been received, and when the heartbeat signal is continuously received a predetermined number of times at the predicted reception timing, the drive energization to the first receiving unit is obtained by the arithmetic unit. Prediction reception The operation mode shifts to the power saving mode in which the operation is stopped until the timing is reached. If the heartbeat signal is not received at the reception timing predicted during the power saving mode, the mode immediately shifts to the normal mode in which the first receiving unit is always energized. Mode control so that the system automatically shifts to the power saving mode while it is determined that the heart rate is stable, and until the timing at which the next heart rate signal is predicted to be received, the receiving unit The present invention can provide a continuous heart rate monitoring system capable of stopping the operation of the device, suppressing unnecessary power consumption, reducing the power consumption of the transmitter, and extending the life of the battery serving as the power source.

[Brief description of the drawings]

FIG. 1 is a diagram showing an external configuration according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state where the detector and the transmitter shown in FIG. 1 are attached to a person to be monitored.

FIG. 3 is a block diagram showing an internal circuit configuration of the detector.

FIG. 4 is a block diagram showing an internal circuit configuration of the receiver.

FIG. 5 is a diagram illustrating transition states of each operation mode.

FIG. 6 is a flowchart showing the contents of a reception process in a rest mode by the CPU of FIG. 5;

FIG. 7 is a flowchart showing the contents of a reception process in a sleep mode by the CPU of FIG. 5;

FIG. 8 is a timing chart showing a reception stop state immediately after a transition from the normal mode to the quiet mode.

FIG. 9 is a timing chart showing a reception stop state immediately after a transition from the rest mode to the sleep mode;

[Explanation of symbols]

1 ... detector, 2 ... transmitter, 3 ... receiver, 4 ... telephone, 5
... Monitored person, 6 ... Band, 11 ... Heart rate detector, 12 ... E
M transmission control unit, 12a oscillation circuit, 18, 32 electromagnetic induction coil, 31 EM reception unit, 34 CPU, 35 arithmetic unit, 36 clock unit, 37 flag register unit, 38 heart rate register ( H
R), 39 register section, 39a x register, 39b t register, 39c tn register, 39d tf register, 40
... Display unit, 41 ... RF transmission unit.

Claims (1)

(57) [Claims] Claims: 1. The device is directly attached to the body of a person to be monitored,
A heartbeat detector having detection means for detecting the heartbeat; first transmission means for converting the heartbeat detected by the detection means into a signal and transmitting and outputting the signal; a first heartbeat signal receiving the heartbeat signal from the heartbeat detector Receiving means, an abnormality judging means for judging a heart rate abnormality of the person to be monitored based on the heartbeat signal received by the first receiving means, and an emergency signal when the abnormality judging means judges that the heart rate of the person to be monitored is abnormal. , A calculating means for predicting and calculating the reception timing of the next heartbeat signal received by the first receiving means, and the first receiving based on the receiving timing obtained by the calculating means. Means for determining whether or not the means has received a heartbeat signal, and the first means when the timing determination means determines that the heartbeat signal has been continuously received a predetermined number of times at the predicted reception timing. When shifting to the power saving mode in which the drive energization to the receiving means is stopped until the next predicted reception timing obtained by the arithmetic means, and it is determined that the heartbeat signal has not been received at the reception timing predicted during this power saving mode A transmitter having mode control means for immediately shifting to a normal mode in which the first receiving means is always energized for driving; a second receiving means for receiving an emergency signal from the transmitter; And a notification processing means for performing notification processing when a heart rate abnormality occurs in accordance with the emergency signal received by the receiving means.