JP4760025B2 - Pulse measuring device and pulse measuring circuit - Google Patents

Description

Based on the electrical signal output from the pulse sensor in a state in which the pulse sensor that receives the light of the light emitting element that emits light at a predetermined period is received by the light receiving element, converts the received light into an electrical signal, and outputs the electrical signal The present invention relates to a pulse measuring device and a pulse measuring circuit for measuring a pulse.

  2. Description of the Related Art Conventionally, there is a pulse measuring device that measures a pulse rate by attaching a pulse sensor composed of an infrared light emitting element and a light receiving element to a body and observing a change in blood flow. As inventions related to these pulse measuring devices, there is known an invention for determining whether or not a pulse sensor is attached at the time of measurement.

For example, an invention that determines whether the pulse sensor is attached or detached by detecting whether or not the pulse sensor is in contact with the skin, and stops driving the pulse sensor when the pulse sensor is not in contact with the skin (for example, cited) In addition to controlling the operation of the pulse measurement circuit by determining whether or not a finger or the like is placed on a metal electrode, and displaying the detected state of the measured pulse as a bar graph, There is an invention (see, for example, cited document 2) that makes the state visible.
JP 2003-70575 A JP 62-60534 A

  Currently, pulse measuring devices are widely used in homes for the purpose of maintaining health and grasping exercise states, in addition to being used in medical institutions for therapeutic purposes and the like. Various usage forms at home are conceivable. For example, there is a use form in which the user measures the pulse rate during exercise such as walking or jogging, and adjusts the amount of exercise based on the measured pulse rate.

  However, a normal pulse measuring device is not a device intended for measuring the pulse rate while the body is operating such as walking. Therefore, if the user wears a pulse sensor at rest before exercise and starts exercise such as walking, the pulse sensor may be detached from the body during exercise or the position of the pulse sensor may be shifted. In some cases, the pulse rate could not be measured correctly.

  In addition, even if it is worn correctly, the amount of light received by the light receiving element will change if it is measured in places where it is exposed to direct sunlight or where it is exposed to sunlight while it is moving, such as walking. In some cases, the pulse rate could not be measured correctly. Therefore, even if the pulse sensor does not come off during exercise, it is necessary for the user to periodically check whether the measurement is correctly performed.

  In addition, there is a case where a pulse sensor is attached, but an incorrect measurement value is displayed because a correct measurement cannot be performed due to deviation from a measurable position, so the user has to check regularly. It had been.

In view of the above problems, an object of the present invention is to provide a pulse measuring device and a pulse measuring circuit that can prompt the user to change the body of the pulse sensor having a pulse detecting unit.

In order to solve the above problems, the pulse measuring device of the invention described in claim 1 is:
A pulse that receives light of a light emitting element (for example, the light emitting diode LED in FIG. 5) that emits light at a predetermined period by a light receiving element (for example, the photodiode PD in FIG. 5), converts the received light into an electric signal, and outputs the electrical signal. In a pulse measurement device that measures a pulse based on an electrical signal output from the pulse sensor in a state where the sensor is attached to the body,
Sample-and-hold means (for example, the sample-and-hold circuit SH in FIG. 5) that samples the converted electric signal at a light emission period of the light-emitting element and holds the voltage value of the sampled electric signal;
First digital conversion means (for example, the first A / D conversion circuit unit 22 in FIG. 5) that converts the voltage value of the electrical signal held by the sample hold means into a digital signal in the same cycle as the sampling;
Noise removing means (for example, capacitor C16, resistor 24 in FIG. 5) for removing a noise signal from the signal output by the sample and hold means;
Second digital conversion means (for example, the second A / D conversion circuit unit 24 in FIG. 5) that converts the signal from which noise has been removed by the noise removal means into a digital signal;
Wearing state determination for determining whether or not there is a change in the wearing state of the pulse sensor based on the digital signal converted by the first digital conversion unit and the digital signal converted by the second digital conversion unit Means (for example, CPU 10 in FIG. 3; step A14 in FIG. 8);
Based on the result determined by the mounting state determination unit, notification unit (for example, the CPU 10 in FIG. 3; step A34 in FIG. 8, step S34 in FIG. 3) that prompts the user to change the mounting state of the pulse sensor. Means 80);
It is characterized by providing.

The invention according to claim 2 is the pulse measuring device according to claim 1,
The voltage value of the digital signal converted by the first digital conversion means and the voltage value of the digital signal converted by the second digital conversion means when it is determined that a change has occurred in the mounting state of the pulse sensor Storage means (for example, ROM 30 in FIG. 3; first state notification audio data 302 in FIG. 7A) for storing a message corresponding to the fluctuation state of
The notification means extracts the message from the storage means based on the voltage value of the digital signal converted by the first digital conversion means and the voltage value of the digital signal converted by the second digital conversion means. (For example, CPU 10 in FIG. 3; step A34 in FIG. 8).

The pulse measuring circuit of the invention described in claim 3 is:
A pulse that receives light of a light emitting element (for example, the light emitting diode LED in FIG. 5) that emits light at a predetermined period by a light receiving element (for example, the photodiode PD in FIG. 5), converts the received light into an electric signal, and outputs the electrical signal. In a pulse measurement circuit that includes a sensor and measures a pulse based on an electrical signal output from the pulse sensor,
A sample-and-hold circuit (for example, the sample-and-hold circuit SH in FIG. 5) that samples the converted electrical signal at a light emission period of the light-emitting element and holds a voltage value of the sampled electrical signal;
A first digital conversion circuit (for example, the first A / D conversion circuit unit 22 in FIG. 5) that converts the voltage value of the electric signal held by the sample hold circuit into a digital signal in the same cycle as the sampling;
A noise removing circuit (for example, a capacitor C16 and a resistor 24 in FIG. 5) for removing a noise signal from the signal output by the sample and hold circuit;
A second digital conversion circuit (for example, the second A / D conversion circuit unit 24 in FIG. 5) that converts a signal from which noise has been removed by the noise removal circuit into a digital signal;
Wearing state determination for determining whether or not there is a change in the wearing state of the pulse sensor based on the digital signal converted by the first digital conversion circuit and the digital signal converted by the second digital conversion circuit A circuit (for example, CPU 10 in FIG. 3; step A14 in FIG. 8);
Based on the result determined by the mounting state determination circuit, a notification circuit (for example, the CPU 10 in FIG. 3; step A34 in FIG. 8; audio output in FIG. 3) that performs notification for prompting the change of the mounting state of the pulse sensor. Means 80);
It is characterized by providing.

According to a fourth aspect of the present invention, in the pulse measurement circuit according to the third aspect ,
The voltage value of the digital signal converted by the first digital conversion circuit and the voltage value of the digital signal converted by the second digital conversion circuit when it is determined that the wearing state of the pulse sensor has changed. A storage circuit (for example, ROM 30 in FIG. 3; first state notification audio data 302 in FIG. 7A) that stores a message corresponding to the fluctuation state of
The notification circuit extracts the message from the storage circuit based on the voltage value of the digital signal converted by the first digital conversion circuit and the voltage value of the digital signal converted by the second digital conversion circuit (For example, CPU 10 in FIG. 3; step A34 in FIG. 8).

  According to the first aspect of the present invention, the wearing state of the pulse sensor is determined based on the digital signal converted by the first digital conversion means and the digital signal converted by the second digital conversion means. And based on the determined result, the alerting | reporting for prompting the change of the mounting state of a pulse sensor can be performed. For this reason, it is possible to accurately measure the pulse by reattaching the pulse sensor by the user himself / herself through this notification.

According to the invention described in claim 3 , the wearing state of the pulse sensor based on the digital signal converted by the first digital conversion circuit and the digital signal converted by the second digital conversion circuit And a notification for prompting the user to change the wearing state of the pulse sensor can be performed based on the determined result. For this reason, it is possible to accurately measure the pulse by reattaching the pulse sensor by the user himself / herself through this notification.

According to the invention described in claim 2, the voltage value of the converted digital signal by the first digital converter means, based on the voltage value of the converted digital signal by the second digital converting means, a message It can be extracted and output.

According to the invention described in claim 4 , the message is transmitted based on the voltage value of the digital signal converted by the first digital conversion circuit and the voltage value of the digital signal converted by the second digital conversion circuit. It can be extracted and output.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment when the present invention is applied to an ear-mounted pulse measuring device 1 will be described in detail with reference to the drawings.

[First Embodiment]
[1.1 Configuration]
[1.1.1 External configuration]
FIG. 1 is a diagram showing an ear-mounted pulse measuring device 1, (a) is a front view of the pulse measuring device 1, and (b) is a perspective view of the pulse measuring device 1. The direction in the description is the direction for the user wearing the pulse measuring device 1. Specifically, the face side (the back side of FIG. 1A, the lower left side of FIG. 1B, the left side of FIG. 2) when wearing the pulse measuring device 1 is the front side and the occipital side (FIG. 1A). The front side, the upper right side of (b), the right side of FIG. 2) is the rear, the left ear side is left, the right ear side is right, the upper is upper, and the lower is lower. Further, the direction in which the left and right arm portions 112R and 112L are close to each other, that is, the direction toward the center of the head is defined as the inner direction, and the opposite is defined as the outer direction.

  The pulse measuring device 1 includes a main body unit 100, a right arm unit 112R, a left arm unit 112L, a right driver unit 110R and a left driver unit 110L that are speaker units, and a pulse sensor unit 106 (ear clip). Composed. The right arm portion 112R is supported at the upper right end portion of the main body portion 100 so as to be urged inward. Further, the left arm portion 112L is supported so as to be urged inward in the upper left end portion of the main body portion 100. The main body 100 is provided with a display 102 and various switches.

  A right driver unit support portion 114R that supports the right driver unit 110R is provided at the tip of the right arm portion 112R. Further, a left driver unit support portion 114L that supports the left driver unit 110L is provided at the distal end portion of the left arm portion 112L. A pulse notification switch S1 is disposed on the right side surface of the right driver unit support portion 114R, and a radio channel selection switch S2 is disposed on the left side surface of the left driver unit support portion 114L.

  The pulse sensor unit 106 has a clip that can be clamped to the earlobe, which is a part of the auricle, and a pulse sensor for optically detecting the pulse is disposed on the clamping surface. The pulse sensor unit 106 is electrically connected via a cable 108 from the left side surface of the main body unit 100. Further, when the user does not use the pulse sensor unit 106, the pulse sensor unit 106 is clamped and locked to the protrusion 122.

  In order to wear the pulse measuring device 1, the user grasps and spreads the right arm portion 112R and the left arm portion 112L in a direction in which the right driver unit 110R and the left driver unit 110L are separated from each other. Then, the pulse measuring device 1 is moved so as to wrap around the head from the occipital region 140 side, and the right driver unit 110R is inserted into the ear canal of the right ear and the left driver unit 110L is inserted into the ear canal of the left ear. Wear 1

  At this time, due to the urging force transmitted to the right driver unit 110R and the left driver unit 110L via the right arm portion 112R and the left arm portion 112L, the right driver unit 110R and the left driver unit 110L are directed in the ear canal. It is pressed (inward direction). Further, as shown in FIG. 2, the back surface of the main body 100 (the front surface of the main body 100) is brought into contact with the lower part of the back head 140, and the posture of the main body 100 is maintained.

  In such a pulse measuring device 1, the following effects are obtained. First, the right driver unit 110R is inserted into the right ear canal and the left driver unit 110L is inserted into the left ear canal, and is pressed toward the inner side of the head by the urging force transmitted through the right arm portion 112R and the left arm portion 112L. As a result, the right driver unit 110R and the left driver unit 110L are reliably inserted into the ear canal. For this reason, it becomes difficult for each driver unit to come off with respect to the movement of the head, and a stable wearing feeling can be obtained.

  In addition, a straight line connecting the right driver unit 110R inserted into the right ear canal and the left driver unit 110L inserted into the left ear canal can serve as a swing shaft for swinging the main body 100 in the vertical direction. The shift of the oscillation axis of the pulse measuring device 1 in the axial direction is suppressed.

  In addition, since the power source unit such as a battery and various control circuits are built in the main body unit 100, the main body unit 100 occupies most of the weight of the pulse measuring device 1 and becomes a heavy object to some extent. Therefore, the main body 100 is brought into contact with the vicinity of the lower part of the back head 140 due to the relationship between its own weight and the swing shaft. Therefore, the pulse measuring device 1 is held in a stable posture in which the main body 100 is in contact with the vicinity of the lower part of the back of the head 140, and even if the user is exercising, the swinging shaft is not swung in the rotation direction. It is suppressed.

  In addition, since there are three places of contact with the head, the left and right ear holes and the back of the head 140, a feeling of obstruction that covers the head like conventional headphones is reduced, and a comfortable wearing feeling is obtained. .

  The right arm portion 112R is pressed against the head from the outside of the right ear pinna and the left arm portion 112L is pressed against the head from the outside of the left ear pinna. Accordingly, the right arm 112R does not hang on the base of the right ear pinna and the left arm 112L does not hook on the base of the left ear pinna, so that the glasses can be worn when the pulse measuring device 1 is worn. .

  Further, the pulse sensor unit 106 connected to the left side surface of the main body unit 100 is locked by sandwiching the earlobe of the left ear. Therefore, since the wearing of the pulse measuring device 1 is completed when the pulse measuring device 1 is worn on the user's head, the cable 108 is unlikely to obstruct the user's movement.

  The pulse sensor unit 106 is sandwiched and locked on the left ear (left side), whereas the pulse notification switch S1 is disposed on the right driver unit support unit 114R (right side). Thereby, the influence with respect to the pulse detection of the pulse sensor unit 106 on the left side by the operation on the right side of the pulse measurement device 1 that is the operation of the pulse notification switch S1 for listening to the measurement result such as the pulse rate can be reduced.

[1.1.2 Internal configuration]
Next, the internal configuration of the pulse measuring device 1 will be described. FIG. 3 is a block diagram of the pulse measuring device 1. As shown in the figure, the pulse measuring device 1 includes a CPU (Central Processing Unit) 10, a pulse detection circuit unit 20, a first A / D conversion circuit unit 22, a second A / D conversion circuit unit 24, and a ROM. (Read Only Memory) 30, RAM (Random Access Memory) 40, radio receiving circuit unit 50, input unit 60, display unit 70, and audio output unit 80.

[1.1.2 (a) Pulse detection circuit unit / A / D conversion circuit unit]
The pulse detection circuit unit 20 is a circuit unit for detecting a pulse, and is a circuit unit including the pulse sensor unit 106 of FIG. As shown in FIG. 1, when the pulse sensor unit 106 is clamped to the user's earlobe by a clip, the pulse sensor provided on the clip clamping surface detects the pulse by contacting the user's ear. To do.

  Here, the pulse sensor is configured to include a light emitting element such as a light emitting diode and a light receiving element such as a phototransistor. Light is emitted from the light emitting element toward the ear, and light transmitted through or reflected by the ear is reflected. When the light receiving element receives the light, the temporal variation (volume pulse wave) of the local volume of the earlobe is detected, and an electrical signal corresponding to the detection result is output as an analog signal.

  The first A / D conversion circuit unit 22 and the second A / D conversion circuit unit 24 are circuit units that convert an analog electrical signal input from the pulse detection circuit unit 20 into a digital data signal.

  Specifically, a pulse signal ct1 and a pulse signal ct2 having a constant period are input from the CPU 10 to the pulse detection circuit unit 20, and the pulse detection circuit unit 20 is driven based on the input pulse signals ct1 and ct2 to detect a pulse. Is made. Then, the signal S1 is output to the first A / D conversion circuit unit 22 and the signal S2 is output to the second A / D conversion circuit unit 24 according to the detected pulse. The signal S1 is converted into a data signal P1 by the first A / D conversion circuit unit 22, and is output to the CPU 10. The signal S2 is converted into a data signal P2 by the second A / D conversion circuit unit 24 and output to the CPU 10. And CPU10 determines the mounting state of the pulse sensor part 106 based on the input data signals P1 and P2.

<Determining how the pulse sensor is attached>
Next, a method in which the CPU 10 determines the mounting state of the pulse sensor unit based on the data signals P1 and P2 will be described. Based on the data signals P1 and P2, the CPU 10 determines the state of the pulse sensor unit as “normally measured”, “the detected pulse is weak”, or “the pulse sensor is not attached”.

  FIG. 4 is a diagram for explaining the relationship between the waveform of each signal and the mounting state. An example of the outline of the waveform of the data signal P1 is shown in the upper stage, and an example of an outline of the waveform of the data signal P2 is shown in the lower stage. In each graph, the horizontal axis represents the time axis and the vertical axis represents the voltage. The two-dot chain line in each graph represents an intermediate potential. In the present embodiment, the intermediate potential of the data signal P1 is 0.6 [V] and the intermediate potential of the data signal P2 is 1.5 [V]. Yes. Note that the scale of the time axis in the graph of FIG. 4 varies depending on each graph. The value of the intermediate potential is actually a value determined by the configuration of the pulse detection circuit of the pulse measuring device, and is not limited to 0.6 [V] and 1.5 [V].

  First, a signal waveform determined to be “normally measured” will be described. The data signal P1 has a substantially intermediate potential and has a waveform that changes stepwise. The reason why it changes stepwise, that is, the potential changes every predetermined time is because the pulse is intermittently detected by the pulse signals ct1 and ct2 having a constant period output from the CPU 10. The data signal P2 is a sawtooth wave having an amplitude of about 1 V with the intermediate potential as the center.

The signal waveform determined as “the detected pulse is weak” is that the data signal P1 is an output having a constant voltage that is substantially the same as the intermediate potential, and the data signal P2 has a slight amplitude centering on the intermediate potential.

  The signal waveform determined as “the pulse sensor is not attached” is that the data signal P1 is an output of a constant voltage that is the same as the power supply voltage (in this case, 3 V) of the pulse detection circuit unit 20, and the data signal P2 is an intermediate potential. Same constant voltage output.

  Then, the CPU 10 determines the state of the pulse sensor unit 106 based on the data signal P1 input from the first A / D conversion circuit unit 22 and the data signal P2 input from the second A / D conversion circuit unit 24.

  First, when it is determined that the voltage value of the data signal P1 slightly fluctuates in the vicinity of the intermediate potential, and the voltage value of the data signal P2 is a sawtooth wave having an amplitude of about 1 V around the intermediate potential, the CPU 10 It is determined that the pulse sensor unit 106 is in a state where a pulse can be detected, that is, a state in which “a pulse is normally detected”.

  On the other hand, when it is determined that the voltage value of the data signal P1 is substantially constant at the intermediate potential and the voltage value of the data signal P2 is close to the intermediate potential, the CPU 10 detects that the pulse sensor unit 106 is mounted, It is determined that the pulse is “weak”. When the output of the data signal P1 is determined to be 3 [V] (= Vdd), the CPU 10 determines that the pulse wave sensor unit 106 is not attached. As described above, the CPU 10 can determine the state of the pulse sensor unit 106 based on the voltage values of the data signal P1 and the data signal P2.

<Configuration of pulse detection circuit>
Next, the circuit configuration of the pulse detection circuit unit 20 will be described with reference to FIG. FIG. 5 is a diagram illustrating a circuit configuration of the pulse detection circuit unit 20, the first A / D conversion circuit unit 22, and the second A / D conversion circuit unit 24. The pulse detection circuit unit 20 includes a light emitting diode LED, a photodiode PD, a sample hold circuit SH, an operational amplifier OP, a constant current circuit BT, transistors TR1 and TR3, resistors R12, R14, R16, R18, R20, R22, R24, R26 and capacitors C10, C12, C14, C16 are provided.

  The constant current circuit BT is a current source that supplies a current for causing the light emitting diode LED to emit light. The light emitting diode LED is a light emitting element that emits light when a predetermined current flows, the constant current circuit BT is connected to the cathode, and the power supply voltage Vdd is applied to the anode.

  The photodiode PD is a light receiving element that passes a current corresponding to the amount of light received, and has an anode connected to one end of the capacitor C10 and one end of the resistor R12, and a power supply voltage Vdd is applied to the cathode. The resistor R12 has one end connected to the anode of the photodiode PD and one end of the capacitor C10, and the other end grounded. Hereinafter, a connection point between the anode of the photodiode PD, one end of the resistor R12, and one end of the capacitor C10 is referred to as a node N4, and a signal at the node N4 is referred to as a signal S4.

  The capacitor C10 is a capacitor for removing a DC component, and has one end connected to one end of the resistor R12 and the anode of the photodiode PD, and the other end connected to one end of the resistor R14 and the base terminal of the transistor TR1. The resistor R14 has one end connected to the other end of the capacitor C10 and the base terminal of the transistor TR1, and the other end grounded.

  The transistor TR1 is a pnp transistor, and has a base terminal connected to the other end of the capacitor C10 and one end of the resistor R14, an emitter terminal connected to one end of the resistor R16 and one end of the sample hold circuit SH, and a collector terminal grounded. Yes. The resistor R16 has one end connected to the emitter terminal of the transistor TR1 and one end of the sample hold circuit SH, and the other end to which the power supply voltage Vdd is applied. Hereinafter, a connection point between the emitter terminal of the transistor TR1, one end of the resistor R16, and one end of the sample hold circuit SH is referred to as a node N3, and a signal at the node N3 is referred to as a signal S3.

  The sample hold circuit SH is a circuit that samples and holds the voltage value of the node N3 in synchronization with the falling edge of the pulse signal ct2 input from the CPU 10, one end of which is connected to the emitter terminal of the transistor TR1 and one end of the resistor R16. One end is connected to one end of the capacitor C12 and the base terminal of the transistor TR3. Here, the capacitor C12 is a capacitor for holding the sampled voltage value. The resistor R16 and the capacitor C12 constitute a low pass filter. Therefore, the sample and hold circuit SH outputs a low frequency component signal from which the high frequency component has been removed by the resistor R16 and the capacitor C12.

  The transistor TR3 is an npn-type transistor. The other end of the sample and hold circuit SH and one end of the capacitor C12 are connected to the base terminal, one end of the resistor R18 and one end of the capacitor C14 are connected to the emitter terminal, and the power supply voltage Vdd is connected to the collector terminal. Is applied. The resistor R18 has one end connected to the emitter terminal of the transistor TR3 and one end of the capacitor C14, and the other end grounded. Hereinafter, a connection point between the other end of the sample hold circuit SH, one end of the capacitor C12, and the base terminal of the transistor TR3 is referred to as a node N1.

  The capacitor C14 is for removing a DC component, and one end is connected to the emitter terminal of the transistor TR3 and one end of the resistor R18, and the other end is connected to one end of the resistor R20, one end of the resistor R22, and the non-inverting terminal of the operational amplifier OP. ing. Also, one end of the resistor R20 is connected to the other end of the capacitor C14, one end of the resistor R22, and the non-inverting terminal of the operational amplifier OP, and the power supply voltage Vdd is applied to the other end. The resistor R22 has one end connected to the other end of the capacitor C14, one end of the resistor R20, and the non-inverting terminal of the operational amplifier OP, and the other end is grounded.

  The operational amplifier OP has a non-inverting terminal at the other end of the capacitor C14, one end of the resistor R20 and one end of the resistor R22, an inverting terminal at one end of the capacitor C16, one end of the resistor R24 and one end of the resistor R26, and an output terminal of the capacitor C16. The other end and the other end of the resistor R24 are connected. Further, the output terminal is connected to the second A / D conversion circuit unit 24. The capacitor C16 has one end connected to the inverting terminal of the operational amplifier OP, one end of the resistor R24 and one end of the resistor R26, and the other end connected to the output terminal of the operational amplifier OP and the other end of the resistor R24. The resistor R24 has one end connected to the inverting terminal of the operational amplifier OP, one end of the capacitor C16 and one end of the resistor R26, and the other end connected to the output terminal of the operational amplifier OP and the other end of the capacitor C16. One end of the resistor R26 is connected to the inverting terminal of the operational amplifier OP, one end of the resistor R24, and one end of the capacitor C16. The operational amplifier OP, the capacitor C16, the resistor R24, and the resistor R26 constitute a non-inverting amplifier circuit, and a signal input from the non-inverting terminal of the operational amplifier OP is amplified and output from the output terminal. Here, the capacitor C16 and the resistor R24 constitute a filter for removing noise. Hereinafter, a connection point between the output terminal of the operational amplifier OP, the other end of the capacitor C16, and the other end of the resistor R24 is referred to as a node N2.

  The first A / D conversion circuit unit 22 is a circuit unit that inputs the voltage of the node N1 as a signal S1, converts it to a digital value, and outputs it as a data signal P1, and the second A / D conversion circuit unit 24 This is a circuit unit that inputs the voltage of the node N2 as the output voltage of the operational amplifier OP as a signal S2, converts it to a digital value, and outputs it as a data signal P2.

<Operation of pulse detection circuit>
The operation of the pulse detection circuit unit 20 will be described. FIG. 6 (1) shows the waveform of the pulse signal ct1, (2) shows the waveform of the pulse signal ct2, and (3) shows the waveform of the signal S4 representing the voltage at the node N4. FIG. 4 (4) shows the waveform of the signal S3 representing the voltage at the node N3 with a dotted line, the waveform of the signal S1 representing the voltage at the node N1 with a solid line, and (5) shows the waveform of the signal S2 representing the voltage at the node N2. Respectively. Each waveform is a schematic waveform in which the characteristic portion is clarified, the horizontal axis indicates a common time axis, and the vertical axis indicates a signal level (voltage).

  The pulse signal ct1 is a pulse wave having an ON period (for example, t10 to t20) of, for example, about 30 μsec and a period of, for example, about 3830 μsec. Hereinafter, the pulse period of the pulse signal ct1 is referred to as an intermittent light emission period. While the pulse signal ct1 is ON, a predetermined current is output from the constant current circuit BT to the light emitting diode LED, and light is emitted from the light emitting diode LED. The light emitted from the light emitting diode LED is received by the photodiode PD. The photodiode PD changes the current according to the received light quantity.

  FIG. 6 (3) shows a waveform representing the voltage of the signal S4. At timing t10, the pulse signal ct1 is turned ON, whereby light begins to be emitted from the light emitting diode LED, and light reception by the photodiode PD is started. Then, the voltage of the signal S4 changes according to the current change by the photodiode PD, and the waveform changes until the timing t20 when the light emission of the light emitting diode LED and the light reception of the photodiode PD are completed.

  Subsequently, the DC component is removed by the capacitor C10, and the potential of the node N3 is raised by a predetermined voltage compared to the potential of the node N4 by the action of the transistor TR1 and the resistor R16. The dotted line in FIG. 6 (4) shows the waveform of the signal S3 at this time. Compared with the signal S4, the voltage is increased.

  The sample hold circuit SH samples at the rising timing of the pulse signal ct2 input from the CPU 10, and holds (holds) the voltage at the falling timing. The voltage is held until the next sampling. Here, the cycle of the pulse signal ct2 is, for example, about 3830 μsec from the timing t20 to the timing t40 (ON period is about 15 μsec). Hereinafter, this cycle is referred to as a sampling cycle. Further, the CPU 10 controls the output of the pulse signal ct1 and the pulse signal ct2 so that the falling timing of the pulse signal ct1 coincides with the falling timing of the pulse signal ct2.

  For example, at timing t20, the signal S3 is sampled and held until timing t40. At timing t40, the voltage of the signal S3 is sampled and held until timing t60. That is, the signal S1 changes at the falling timing of the pulse signal ct2, and has a constant waveform until the falling timing of the next pulse signal ct2.

  The voltage of the node N1 indicated by the signal S1 is returned to the voltage before being pulled up by the transistor TR1 and the resistor R16 by the action of the transistor TR3 and the resistor R18. Further, an AC component is extracted by the action of the capacitor C14, amplified by an amplifier circuit unit including an operational amplifier OP, and output as a signal S2.

[1.1.2 (b) ROM / RAM]
The ROM 30 is a read-only memory that stores an initial program for performing various initial settings, hardware inspections, loading of necessary programs, and the like. The CPU 10 sets the operating environment of the pulse measuring device 1 by executing this initial program when the pulse measuring device 1 is turned on.

  The ROM 30 stores various programs related to the operation of the pulse measuring device 1 such as radio reception processing, various setting processing, various communication processing, and programs for realizing various functions of the pulse measuring device 1. The first state notification sound data 302, the first pulse notification sound data 304, the first pulse measurement program 306, and the pulse interval detection program 308 are stored.

  As shown in FIG. 7A, the first state notification sound data 302 is a table in which the voltage conditions of the data signals P1 and P2 and the notification sound data are stored in association with each other. For example, the notification audio data “please wear ear clips” is stored in association with the condition when the data signal P1 is the power supply voltage Vdd and the data signal P2 is the intermediate potential (1.5 [V]). Has been. Further, in association with the condition when the data signal P1 is the intermediate potential (0.6 [V]) and the data signal P2 is the intermediate potential (1.5 [V]), the notification audio data “Ear clip. Please check "is stored.

  As shown in FIG. 7B, the first pulse notification sound data 304 is a table in which the pulse rate condition and the notification sound data are stored in association with each other. Corresponding to the condition when the pulse rate is “less than 30 or 180 or more”, notification voice data “Please exercise so that the pulse falls within the measurement range” is stored. Further, in association with the condition when the pulse rate is “200 or more”, the notification voice data “Please avoid noise sources” is stored.

  The RAM 30 is a memory that can be written at any time to temporarily hold various programs executed by the CPU 10, data related to the execution of these programs, and the like.

[1.1.2 (c) CPU]
The CPU 10 is a central processing unit that executes processing based on a predetermined program in accordance with an input instruction and transfers instructions and data to each functional unit. Specifically, the CPU 10 reads a program stored in the ROM 30 in response to an operation signal input from the input unit 60, and executes processing according to the program. Then, a display control signal is appropriately output to the display unit 70 to display the processing result.

  Furthermore, in this embodiment, the CPU 10 executes a first pulse measurement process (see FIG. 8) according to the first pulse measurement program 306 of the ROM 30 and a pulse interval detection process (see FIG. 8) according to the pulse interval detection program 308. 9) is executed as a subroutine.

  Specifically, the CPU 10 determines whether or not the pulse is normally detected from the data signal P1 and the data signal P2 in the first pulse measurement process. Here, when the pulse is normally detected, the pulse rate is calculated from the detected pulse, and the calculated pulse rate is notified. When the pulse is not detected normally, the state of the pulse sensor unit 106 is determined based on the data signals P1 and P2, and a notification sound is output according to the determined result.

[1.1.2 (d) Radio receiving circuit section]
The radio receiving circuit unit 50 is a known circuit unit that receives radio broadcasts, receives radio waves from a broadcasting station (frequency) set by a user, and demodulates audio signals.
[1.1.2 (e) Input unit, display unit, audio output unit, etc.]
The input unit 60 corresponds to various switches such as the power switch S6 shown in FIG. 1 and outputs a signal of the pressed switch to the CPU 10. The input unit 60 implements a control command input means for instructing execution of processing.

  The display unit 70 displays various screens based on display signals output from the CPU 10, and is configured by an LCD (Liquid Crystal Display) or the like and corresponds to the display 102 shown in FIG.

  The audio output unit 80 outputs sound in accordance with the audio signal output from the CPU 10, and includes a speaker, an earphone, and the like. The audio output unit 80 corresponds to the left driver unit 110L and the right driver unit 110R shown in FIG.

[1.2 Process flow]
[1.2.1 First pulse measurement process]
First, the first pulse measurement process will be described. The first pulse measurement process is a process in which the CPU 10 reads and executes the first pulse measurement program 306 stored in the ROM 30.

  First, the CPU 10 causes the light emitting element to emit light intermittently (step A10). Specifically, a pulse signal ct1 is output with the pulse period being an intermittent light emission period (eg, 3830 μsec) and the ON period being, eg, 30 μsec. Subsequently, the CPU 10 starts counting by the first timer (step A12).

  The CPU 10 determines whether or not the current pulse is normally detected based on the data signal P1 and the data signal P2 (step A14). Specifically, the CPU 10 determines that the voltage value of the data signal P1 slightly fluctuates in the vicinity of the intermediate potential, and the voltage value of the data signal P2 is a sawtooth wave having an amplitude of about 1 V centering on the intermediate potential. In this case, it is determined that “the pulse is normally detected”.

  When determining that the pulse is normally detected (step A14; Yes), the CPU 10 stops counting the second timer and clears the value counted by the second timer (step A16).

  Subsequently, the CPU 10 executes a pulse interval detection process (FIG. 9), and detects a pulse interval based on the data signal P2 (step A18). Then, the CPU 10 calculates the pulse rate from the detected pulse interval (step A20).

  When the pulse rate calculated in step A20 is in the range of “30 or more and less than 180”, it is determined as a normal range (hereinafter referred to as “normal range” as appropriate) (step A22). And when the value counted by the 1st timer has passed the fixed time (step A26; Yes), the pulse rate calculated in step A20 is alert | reported (step A28). Here, as a method for the CPU 10 to notify the pulse rate, a method for displaying the pulse rate on the display unit 70 or a method for outputting the audio from the audio output unit 80 may be used.

  On the other hand, when it is determined that the pulse rate calculated in step A22 is not in the normal range (step A22; No), the CPU 10 reads out the notification sound data corresponding to the pulse rate from the first state notification sound data 302 and outputs the sound. The voice is output from the unit 80 (step A24). For example, when the calculated pulse rate is “20”, the condition “less than 30” in the first state notification sound data 302 of FIG. Therefore, the CPU 10 reads out the notification voice data “Please exercise such that the pulse falls within the measurement range” and outputs the voice from the voice output unit 80. Further, when the calculated pulse rate is “240”, the condition “200 or more” in the first state notification sound data 302 is satisfied. Therefore, the CPU 10 reads out the notification voice data “Please use it avoiding noise generation sources” and output the voice from the voice output unit 80.

  In Step A14, when it is determined that the pulse is not normally detected based on the data signals P1 and P2 (Step A14; No), the CPU 10 determines whether or not the second timer is counting (Step A14). A30). If it is determined that the second timer is not counting (step A30; No), the CPU 10 starts counting by the second timer (step A32).

  Subsequently, the CPU 10 determines the condition that the voltage values of the data signals P <b> 1 and P <b> 2 are satisfied from the first state notification sound data 302, and outputs the notification sound according to the notification sound data corresponding to the satisfied condition to the sound output unit 80. (Step A34). For example, when the voltage value of the data signal P1 is 3 [V] (Vdd) and the voltage value of the data signal P2 is 1.5 [V], the CPU 10 sets the first state notification audio data 302 of FIG. Satisfy the upper condition. For this reason, the CPU 10 reads the notification sound data “please wear ear clips” and causes the sound output unit 80 to output the notification sound.

  Further, when the voltage value of the data signal P1 is 0.6 [V] and the voltage value of the data signal P2 is 1.5 [V], the CPU 10 lowers the first state notification audio data 302 in FIG. Satisfy the conditions. For this reason, the CPU 10 reads the notification sound data “please check the ear clip” and causes the sound output unit 80 to output the notification sound.

  Subsequently, when the count time of the second timer has not passed the predetermined time (step A36; No), the process proceeds to step A14. Further, when the count time of the second timer has passed a certain time (step A36; Yes), the CPU stops the output of the pulse signal ct1, thereby causing the light emitting element (light emitting diode LED) to emit light. Stop (step A38). Then, the first pulse measurement process is terminated.

[1.2.2 Pulse interval detection processing]
Next, the pulse interval detection process will be described with reference to FIGS. The pulse interval detection process is a process in which the CPU 10 reads and executes the pulse interval detection program 308 stored in the ROM 30.

While the data signal P2 changes with time, the CPU 10 calculates, for example, a total of 16 consecutive voltage values as needed (step B10). “A ₀ , a ₁ , a ₂ , a ₃ ,...” Shown in FIG. 10 indicates a continuous voltage value of the data signal P2. Here, the sum of 16 consecutive voltage values from a ₀ to a ₁₅ is b ₀ . Similarly, the sum of 16 consecutive voltage values from a ₁ to a ₁₆ is b ₁ . The same applies thereafter.

Subsequently, the CPU 10 determines whether or not the current data signal P2 is a waveform change point based on the sum calculated last time, the sum calculated last time, and the sum calculated this time (step B12). . For example, based on b ₀ , b ₁ , and b ₂ shown in FIG. 10, it is determined whether or not the current value (b ₂ ) is a waveform change point.

  When it is determined that the waveform is a change point, the period from the change point determined last time to the change point determined this time is measured as the pulse period (step B14).

[1.3 Effect]
As described above, according to the first embodiment, it is possible to determine whether or not the pulse is normally detected based on the data signals P1 and P2 output from the pulse detection circuit unit 20. In addition, when the pulse is not normally detected, a notification sound according to the wearing state of the pulse sensor unit 106 can be output.

  In addition, when the pulse rate is calculated based on the normally detected pulse, the notification output corresponding to the pulse rate is output from the audio output unit 80 even when the calculated pulse rate is not within the normal range. be able to. Furthermore, when a pulse is not detected for a certain time or more, power consumption can be suppressed by stopping the light emission of the light emitting element.

[Second Embodiment]
Next, a second embodiment to which the present invention is applied will be described.

[2.1 Configuration]
FIG. 11 is a block diagram of the pulse measuring device 1 in the second embodiment. As shown in the figure, the pulse measurement device 1 includes a CPU 10, a pulse detection circuit unit 20, a second A / D conversion circuit unit 24, a ROM 32, a RAM 40, a radio reception circuit unit 50, and an input unit 60. The display unit 70 and the audio output unit 80 are configured. Hereinafter, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 12, the pulse detection circuit unit 20 has the same configuration as the pulse detection circuit unit 20 in the first embodiment. Here, the signal output from the pulse detection circuit unit 20 to the CPU 10 in the second embodiment is only the data signal P2.

  The data signal P2 is a signal obtained by digitizing the analog signal S2 output from the pulse detection circuit unit 20 in the second A / D conversion circuit unit 24. Specifically, the second A / D conversion circuit unit 24 converts the minimum voltage 0 [V] of the signal S2 into a digital value “0” and the maximum voltage 3 [V] of the signal S2 into a digital value “1023”. Thus, the data signal P2 is generated.

  Compared with the ROM 30 of the first embodiment shown in FIG. 3, the ROM 32 replaces the first state notification sound data 302 with the second state notification sound data 320 and the first pulse measurement program 306 with the second pulse measurement program 322. It is a configuration.

  As shown in FIG. 13, the second state notification audio data 320 is a table in which the variation amount of the data signal P2 and the notification audio data are stored in association with each other. For example, the notification voice data “please wear ear clips” is stored in association with the fluctuation amount “0” of the data signal P2. In addition, the notification voice data “Check the ear clip” is stored in association with the fluctuation amount “1 to 10” of the data signal P2.

  Here, the fluctuation amount of the data signal P2 refers to the amplitude value of the data signal P2 converted into a digital signal. For example, when the minimum value of the digital value of the data signal P2 is “450” and the maximum value is “550”, the variation amount is “100”.

  The second pulse measurement program 322 is a program for realizing the second pulse measurement process (see FIG. 14) in the present embodiment, and the second pulse measurement process is executed by the CPU 10 executing the second pulse measurement program. Realized. Specifically, it is determined whether or not the pulse can be normally detected from the value of the data signal P2. Specifically, for example, when the fluctuation amount of the data signal P2 is “11” or more, it is determined that the pulse can be normally detected. When the fluctuation amount is “11” or more, the pulse interval is detected from the data signal P2, and the pulse rate is calculated from the detected pulse interval. When the fluctuation amount is less than “11”, the state of the pulse sensor unit 106 is determined from the fluctuation amount of the data signal P2, and a notification sound corresponding to the determined result is output.

[2.2 Process flow]
Next, operation | movement of the pulse measuring device 1 in 2nd Embodiment is demonstrated with reference to figures. FIG. 14 is a flowchart for explaining the operation of the pulse measurement device 1 according to the second pulse measurement process. Here, the process from step D16 to D28 in the second pulse measurement process is the same as the process from step A16 to A28 in the first pulse measurement process shown in FIG.

  First, the CPU 10 causes the light emitting element to emit light intermittently (step D10). Specifically, the pulse signal ct1 is output with the pulse period as an intermittent light emission period (3830 μsec) and the ON period as 30 μsec. Subsequently, the CPU 10 starts counting by the first timer (step D12).

  Subsequently, the CPU 10 determines whether or not the variation amount of the data signal P2 is “11” or more (step D14). When the fluctuation amount of the data signal P2 is “11” or more, the CPU 10 executes Steps D16 to D28.

  When the fluctuation amount of the data signal P2 is less than “11” (step D14; No), the CPU 10 determines whether or not the second timer is counting (step D30). If it is determined that the second timer is not counting (step D30; No), the CPU 10 starts counting by the second timer (step D32).

  The CPU 10 reads the notification sound data corresponding to the fluctuation amount of the data signal P2 from the second state notification sound data 320, and outputs the notification sound according to the read notification sound data from the sound output unit 80 (step D34). ). For example, when the fluctuation amount of the data signal P <b> 2 is “0”, the CPU 10 reads the notification sound data “please wear ear clips” from the second notification sound data 320 of FIG. 13, and outputs the notification sound from the sound output unit 80. Output audio.

  If the count time of the second timer has not elapsed (step D36; No), the process proceeds to step D14. If the count time of the second timer has elapsed (step D36; Yes), the CPU 10 stops the light emission of the light emitting element (light emitting diode LED) by stopping the output of the pulse signal ct1. (Step D38). Then, the second pulse measurement process is terminated.

[2.3 Effects]
Thus, according to the second embodiment, whether or not the pulse is normally detected based on the fluctuation amount of the data signal P2 even when the signal output from the pulse detection circuit unit 20 is the single data signal P2. Can be determined. In addition, when the pulse is not normally detected, a notification sound according to the wearing state of the pulse sensor unit 106 can be output.

[Modification]
In the above-described embodiment, an example in which the present invention is applied to an ear-mounted device has been described. However, a product to which the present invention is applicable is not limited to this. For example, the pulse sensor may be mounted on other parts such as a finger instead of the earlobe. In addition, although the pulse measurement device has been described as having a radio function, a music playback device may be provided.

(A) of the pulse measuring device in this invention is a front view, (b) is the figure which showed the perspective view. It is the figure which showed the state with which the pulse measuring device in this invention was mounted | worn. It is the figure which showed the block diagram of the pulse measuring device in 1st Embodiment. It is a figure explaining the method of determining the mounting state of a pulse sensor based on the signal output from the pulse detection circuit part in 1st Embodiment. It is the figure which showed the circuit structure of the pulse detection circuit part in 1st Embodiment. It is the figure which showed the waveform which concerns on operation | movement of the pulse detection circuit part in 1st Embodiment. It is the figure which showed an example of the data structure of (a) 1st state alerting | reporting audio | voice data and (b) 1st pulse alerting | reporting audio | voice data in 1st Embodiment. It is the figure which showed the operation | movement flow of the 1st pulse measurement process in 1st Embodiment. It is the figure which showed the operation | movement flow of the pulse interval detection process in 1st Embodiment. It is a figure explaining the pulse extraction method in a 1st embodiment. It is the figure which showed the block diagram of the pulse measuring device in 2nd Embodiment. It is the figure which showed the circuit structure of the pulse detection circuit part in 2nd Embodiment. It is the figure which showed an example of the data structure of the 2nd state alerting | reporting audio | voice data in 2nd Embodiment. It is the figure which showed the operation | movement flow of the 2nd pulse measurement process in 2nd Embodiment.

Explanation of symbols

1 Pulse measuring device 10 CPU
20 Pulse detection circuit 22 1st A / D conversion circuit part 24 2nd A / D conversion circuit part 30, 32 ROM
302 First state notification sound data 304 First pulse notification sound data 306 First pulse measurement program 308 Pulse interval detection program 320 Second pulse notification sound data 322 Second pulse measurement program 40 RAM
50 Radio receiving circuit section 60 Input section 70 Display section 80 Audio output section 100 Main body section 106 Pulse sensor section 110L Left driver unit 110R Right driver unit 112L Left arm section 112R Right arm section

Claims (4)

Based on the electrical signal output from the pulse sensor in a state in which the pulse sensor that receives the light of the light emitting element that emits light at a predetermined period is received by the light receiving element, converts the received light into an electrical signal, and outputs the electrical signal In the pulse measuring device that measures the pulse,
Sample and hold means for sampling the converted electrical signal at a light emission period of the light emitting element and holding a voltage value of the sampled electrical signal;
First digital conversion means for converting the voltage value of the electrical signal held by the sample hold means into a digital signal at the same cycle as the sampling;
Noise removing means for removing a noise signal from the signal output by the sample and hold means;
Second digital conversion means for converting a signal from which noise has been removed by the noise removal means into a digital signal;
Wearing state determination for determining whether or not there is a change in the wearing state of the pulse sensor based on the digital signal converted by the first digital conversion unit and the digital signal converted by the second digital conversion unit Means,
Based on the result determined by the mounting state determination unit, a notification unit that performs notification for prompting a change in the mounting state of the pulse sensor;
A pulse measuring device comprising: The voltage value of the digital signal converted by the first digital conversion means and the voltage value of the digital signal converted by the second digital conversion means when it is determined that a change has occurred in the mounting state of the pulse sensor Storage means for storing a message corresponding to the fluctuation state of
The notification means extracts the message from the storage means based on the voltage value of the digital signal converted by the first digital conversion means and the voltage value of the digital signal converted by the second digital conversion means. The pulse measuring device according to claim 1, wherein the pulse measuring device outputs the pulse. A light-receiving element that receives light from a light-emitting element that emits light at a predetermined period is provided, and a pulse sensor that converts the received light into an electric signal and outputs the electric signal is provided. In the pulse measurement circuit,
A sample-and-hold circuit that samples the converted electrical signal at a light emission period of the light-emitting element and holds a voltage value of the sampled electrical signal;
A first digital conversion circuit that converts the voltage value of the electrical signal held by the sample and hold circuit into a digital signal in the same cycle as the sampling;
A noise removing circuit for removing a noise signal from the signal output by the sample and hold circuit;
A second digital conversion circuit for converting a signal from which noise has been removed by the noise removal circuit into a digital signal;
Wearing state determination for determining whether or not there is a change in the wearing state of the pulse sensor based on the digital signal converted by the first digital conversion circuit and the digital signal converted by the second digital conversion circuit Circuit,
Based on the result determined by the mounting state determination circuit, a notification circuit that performs notification for prompting a change in the mounting state of the pulse sensor;
A pulse measurement circuit comprising: The voltage value of the digital signal converted by the first digital conversion circuit and the voltage value of the digital signal converted by the second digital conversion circuit when it is determined that the wearing state of the pulse sensor has changed. A storage circuit for storing a message corresponding to the fluctuation state of
The notification circuit extracts the message from the storage circuit based on the voltage value of the digital signal converted by the first digital conversion circuit and the voltage value of the digital signal converted by the second digital conversion circuit 4. The pulse measurement circuit according to claim 3 , wherein the pulse measurement circuit outputs the pulse.

Images