JP7569685B2 - Medical Devices - Google Patents

Description

The present invention relates to medical equipment, for example, a Holter electrocardiogram recording device.

One type of electrocardiogram recording device in the past was the Holter electrocardiogram recording device. Since Holter electrocardiogram recording devices need to be worn by patients for long periods of time, there is a demand for them to be small and lightweight in order to reduce the burden on the patient. Such a small and lightweight Holter electrocardiogram recording device is described, for example, in Patent Document 1.

A conventional Holter ECG recording device has a device body and a battery cover that is attached to the device body so that it can be opened and closed freely. A battery can be loaded into the device body by opening the battery cover. When the battery cover is closed, power supply voltage from the battery is supplied to the electrical circuit of the device body.

Figure 1A is a perspective view showing an example of the configuration of a conventional Holter electrocardiogram recording device. Figure 1B is a perspective view showing an example of the configuration of a battery cover.

The Holter ECG recording device in FIG. 1A is designed so that a battery cover 20 is inserted into the device body 10. The device body 10 has engagement holes 11, 12, a display unit 13, an event button 14, etc. The display unit 13 is composed of, for example, a liquid crystal display device. When the event button 14 is pressed, recording of an ECG begins.

The battery cover 20 has locking claws 21, 22 and a battery holder 23. A protrusion 24 is formed on the bottom of the battery holder. The locking claws 21, 22 are locked into the locking holes 11, 12 when the battery cover 20 is inserted into the device body 10. The battery holder 23 holds the button battery 1. When the battery cover 20 is inserted into the device body 10, two terminals (not shown) on the device body 10 come into contact with two electrodes of the button battery 1, and the power supply voltage of the button battery 1 is supplied to the device body 10.

Furthermore, the Holter ECG recording device has a function of recording the opening of the battery cover 20 as a log. A more specific explanation will be given. The device body 10 is provided with a lever (not shown) that moves when the protrusion 24 of the battery cover 20 abuts against it, and a switch (not shown) that is operated by the lever. When the battery cover 20 is inserted into the device body 10, the lever is pushed in by the protrusion 24, and as a result, the switch is turned on. On the other hand, when the battery cover 20 is removed from the device body 10, the lever returns to the release position, and as a result, the switch is turned off. In this way, the switch is turned on and off depending on the attachment state of the battery cover 20 to the device body 10, and this is recorded as a log in the memory unit (not shown) of the device body 10.

If the battery cover 20 of a Holter ECG recording device is opened while recording an ECG, the power supply to the electrical circuit of the device body 10 is cut off, and the ECG cannot be recorded. In this case, it may be necessary to start recording the ECG again from the beginning, resulting in a significant waste of time.

Taking this into consideration, in order to confirm whether the interruption of the power supply to the electrical circuit of the device main body 10 is due to the opening of the battery cover 20, Holter ECG recording devices are generally configured to record, as a log, the fact that the battery cover has been opened as described above.

JP 2016-043068 A

However, in conventional Holter ECG recording devices, in order to log the opening of the battery cover, it is necessary to provide mechanisms such as the protrusion 24 and lever described above, as well as a circuit board area for switches, etc. This is an obstacle to making the Holter ECG recording device smaller and lighter.

The present invention was made in consideration of the above points, and provides a medical device that can record a log of the open state of the battery cover without hindering miniaturization and weight reduction.

One embodiment of the medical device of the present invention is
A device body having an electric circuit for recording an electrocardiogram;
a battery cover that is attached to the device body so as to be freely opened and closed;
a power supply line for supplying a power supply voltage of the battery to an electric circuit of the device body when the battery cover is in a closed state;
an open state determination unit that detects a voltage of the power supply line and determines that the battery cover is in an open state when the voltage is equal to or lower than a threshold;
a recording unit that records, as a log, a time at which the open state determination unit determines that the battery cover is in an open state;
has.

According to the present invention, since there is no need to provide a dedicated mechanism or switch for recording the open state log of the battery cover, it is possible to realize a medical device that can record the open state log of the battery cover without hindering miniaturization and weight reduction.

FIG. 1 is a perspective view showing a configuration example of a conventional Holter electrocardiogram recording device. FIG. 1 is a perspective view showing a configuration example of a conventional battery cover; FIG. 1 is a perspective view showing the appearance of a Holter electrocardiogram recording device according to an embodiment; FIG. 1 is a perspective view showing a battery cover in an open state. Side view showing the locking position of the locking part Side view showing the unlocked position of the lock A block diagram showing the circuit configuration of a Holter electrocardiogram recording device according to an embodiment. FIG. 1 is a diagram for explaining detection of the open/closed state of a battery cover according to an embodiment;

The following describes in detail the embodiments of the present invention with reference to the drawings.

Figures 2 and 3 are perspective views showing the appearance of a Holter electrocardiogram recording device according to an embodiment of the present invention. Figure 2 is a perspective view showing the battery cover 120 in a closed state, and Figure 3 is a perspective view showing the battery cover 120 in an open state.

The Holter electrocardiogram recording device 100 has a device body 110 and a battery cover 120 that is attached to the device body 110 so as to be freely opened and closed.

The device main body 110 has a display unit 111, an event button 112a, an enter button 112b, a battery storage unit 113, and locking claws 114, 115. The display unit 111 is composed of, for example, a liquid crystal display device. The user can switch the display and perform various settings by operating the event button 112a and the enter button 112b. When the event button 112a is pressed, recording of an electrocardiogram is started. Even if the event button 112a is not pressed, recording of an electrocardiogram is automatically started by a timer when a predetermined time (for example, 10 minutes) has elapsed since power was turned on. The battery storage unit 113 stores, for example, a AAA battery.

The battery cover 120 has a locking portion 121, a rotating shaft 122, a terminal portion 123, engagement grooves 124, 125, and an engagement claw 126. The battery cover 120 is rotatably attached to the device body 110 via the rotating shaft 122. The battery cover 120 is also slidable in the directions of the arrows a and b by a sliding mechanism (not shown).

In the closed state shown in FIG. 2, the engagement grooves 124 and 125 engage with the engagement claws 114 and 115, and the engagement claw 126 engages with the engagement groove 116, thereby locking the battery cover 120 to the device body 110 in the closed state.

In this closed state, when the user slides the battery cover 120 in the direction of the arrow a in the figure, the engagement grooves 124, 125 move away from the engagement claws 114, 115, and the engagement claw 126 moves away from the engagement groove 116. From this state, when the user rotates the battery cover 120 around the rotation shaft 122, the battery cover 120 moves to the open state as shown in FIG. 3.

When the battery cover 120 goes from an open state to a closed state, the opposite operation is performed. That is, in the open state shown in FIG. 3, the user first rotates the battery cover 120 around the rotation axis 122 to close the battery cover 120. Next, when the user slides the battery cover 120 in the direction of the arrow b in the figure, the engagement grooves 124, 125 engage with the engagement claws 114, 115, and the engagement claw 126 engages with the engagement groove 116. This restricts the movement of the battery cover 120 in the rotational direction, and the closed state of the battery cover 120 is maintained.

When the locking portion 121 is operated to the locked position shown in FIG. 4A in this closed state, the battery cover 120 is restricted from sliding in the direction of the arrow b. On the other hand, when the locking portion 121 is operated to the unlocked position shown in FIG. 4B, the restriction on the battery cover 120 sliding in the direction of the arrow b is released.

Here, a terminal portion 123 is provided on the inside of the battery lid 120. The terminal portion 123 is a metal plate extending in the longitudinal direction of the battery lid 120, and when the battery lid 120 is in the closed state, the terminal portion 123 contacts one of the two terminals of the battery and also contacts a terminal 117 that protrudes from the device body 110 in the direction of the battery lid 110. The terminal 117 is connected to the power supply line of the device body 110.

Therefore, when the battery cover 120 is in the closed state, a first terminal (not shown) provided at the back of the battery housing section 113 is connected (contacted) to one of the two terminals of the battery, and a terminal section 123 as a second terminal provided on the battery cover 120 is connected (contacted) to one of the two terminals of the battery. Then, the first terminal (not shown) and the second terminal (terminal section 123) are electrically connected to the power supply line in the device main body 110, so that the battery power supply voltage is supplied to the electrical circuit of the device main body 110.

On the other hand, when the battery cover 120 is in the open state, the second terminal (terminal portion 123) provided on the battery cover 120 is separated from the battery terminal, and the power supply voltage is no longer supplied to the electrical circuit of the device main body 110.

Figure 5 is a block diagram showing the circuit configuration of the Holter ECG recording device 100.

The Holter electrocardiogram recording device 100 has a CPU (Central Processing Unit) 131. The CPU 131 is connected to the display unit 111, the event button 112a, the enter button 112b, the ECG unit 133, the NAND flash memory unit 134, the SD card unit 135, the buzzer unit 136, the serial communication connector 137, the acceleration detection unit 138, and the RTC (Real Time Clock) unit 144, and controls these units or inputs signals from these units to perform predetermined processing.

The CPU 131 has a calculation unit 131a, a Ferroelectric Random Access Memory (FRAM) (registered trademark) 131b, and a Random Access Memory (RAM) 131c. The FRAM 131b stores programs and the like for the CPU 131 to execute predetermined processes. In the CPU 131, the calculation unit 131a reads the programs from the FRAM 131b and performs calculations according to the programs using the RAM 131c to execute the predetermined processes.

FRAM 131b also stores processing settings for electrocardiogram recording. For example, the processing settings include recording format (compatible mode, normal mode), recording time, recording channel (12-lead, 2ch, 3ch), sampling frequency, drift filter (ON, OFF), pacemaker detection (ON, OFF), pacemaker detection sensitivity, etc.

Electrodes worn by the patient are connected to the ECG connector 132. The ECG unit 133 performs predetermined processing, such as sampling and filtering, on the electrocardiogram signal input from the ECG connector 132 to obtain an electrocardiogram.

The NAND flash memory unit 134 stores electrocardiograms and other data acquired by the ECG unit 133.

An SD card is inserted into the SD card section 135. The CPU 131 can write the electrocardiogram acquired by the ECG section 133 to the SD card. The CPU 131 can also read information written to the SD card. For example, if processing setting values for recording an electrocardiogram are written to the SD card, the processing setting values can be read from the SD card and stored in the FRAM 131b.

The buzzer unit 136 is controlled by the CPU 131 and can notify the patient or operator by emitting a buzzer sound when, for example, the patient presses the event button 112a while an electrocardiogram is being recorded or when an error occurs in the device.

The serial communication connector 137 is connected via a cable to an external device such as an external analysis device or a personal computer, and is capable of outputting, for example, the electrocardiogram stored in the NAND flash memory unit 134 to an external analysis device. In addition, the above-mentioned processing setting values can also be input via the serial communication connector 137.

The acceleration detection unit 138 detects the body movement of the patient wearing the Holter ECG recording device 100 as acceleration. The detection results are stored in the NAND flash memory unit 134 or an SD card.

In addition to this configuration, the Holter ECG recording device 100 has a battery terminal 141, a DC-DC conversion unit 142, an open state determination unit 143, an RTC (Real Time Clock) unit 144, a main battery 151, and a backup battery 152.

The battery terminal 141 corresponds to the first terminal (not shown) of the device body 110, the terminal 117, and the second terminal (terminal portion 123) of the battery cover 120 described above. The main battery 151 corresponds to the AAA battery housed in the battery housing portion 113.

The RTC unit 144 is driven by the main battery 151 or the backup battery 152. In other words, the RTC unit 144 is driven by the main battery when the power supply voltage from the main battery 151 is supplied to the electrical circuit of the device body 110, and is driven by the backup battery 152 when the power supply voltage from the main battery 151 is not supplied to the electrical circuit of the device body 110. In other words, the RTC unit 144 is driven by the backup battery 152 even when the battery cover 120 is open and power supply voltage is not supplied from the main battery 151. The backup battery 152 is, for example, a small button battery.

The battery terminal 141 is electrically connected to a DC-DC conversion unit 142 and an open state determination unit 143. The DC-DC conversion unit 142 converts the battery voltage applied to the battery terminal 141 into DC-DC and supplies it to the electrical circuit within the device main body 110.

In practice, the open state determination unit 143 is connected to the second terminal (terminal portion 123) provided on the battery cover 120 via the first terminal or terminal 117 provided on the device main body 110, detects the voltage of the first terminal or second terminal, and determines that the battery cover 120 is in the open state when the voltage falls below a threshold value.

When the open state determination unit 143 obtains a result of the open state determination, it outputs a signal indicating this to the RTC unit 144.

The RTC unit 144 records the time when the open state determination unit 143 determines that the battery cover 120 is open as a log.

Figure 6 is a diagram used to explain the detection of the open/closed state of the battery cover 120 according to this embodiment. The upper part of the figure shows the open/closed state of the battery cover 120, and the lower part shows the terminal voltage.

During the period from time t1 to time t2, the battery cover 120 is completely closed, and the terminal voltage is a constant value that corresponds to the voltage of the main battery 151.

The period from time t2 to time t4 is the period immediately after the battery cover 120 transitions from the closed state to the open state. During this period, the charge stored in the circuit of the open state determination unit 143 is gradually discharged, so the terminal voltage also gradually drops.

When the terminal voltage becomes equal to or lower than the threshold value th1 at time t3, the open state determination unit 143 determines that the battery cover 120 is open and notifies the RTC unit 144 of this fact. As a result, the RTC unit 144 records as a log the time when the battery cover 120 is open, in other words, the time when the power supply from the main battery 151 to the electrical circuit is stopped.

As described above, according to this embodiment, the Holter electrocardiogram recording device 100 comprises a device body 110 having a first terminal connected to one of the two terminals of a battery (main battery 151), a battery cover 120 that is attached to the device body 110 so as to be freely opened and closed and has a second terminal (terminal portion 123) connected to the other of the two terminals of the battery (main battery 151), a terminal 117 that takes in power from the battery (main battery 151) via the terminal portion 123, and a terminal 117 that takes in power from the battery (main battery 151) when the battery cover 120 is in a closed state. The device has a power supply line that supplies the power supply voltage of the battery (main battery 151) to the electrical circuit of the device body 110 when both the first and second terminals are connected to the two terminals of the battery (main battery 151), an open state determination unit 143 that detects the voltage of the first or second terminal and determines that the battery cover 120 is open when the voltage is equal to or lower than a threshold value th1, and a recording unit (RTC unit 144) that records the time when the open state determination unit 143 determines that the battery cover 120 is open as a log.

As a result, there is no need to provide a dedicated mechanism or switch for recording the open state log of the battery cover 120, making it possible to realize a Holter ECG recording device 100 that can record the open state log of the battery cover 120 without hindering miniaturization and weight reduction.

The above-described embodiments are merely examples of the implementation of the present invention, and the technical scope of the present invention should not be interpreted in a limiting manner based on these. In other words, the present invention can be implemented in various forms without departing from its gist or main characteristics.

In the above embodiment, the open state determination unit 143 has determined that the battery cover 120 is in the open state when the voltage of the first terminal or the second terminal becomes equal to or lower than the threshold value th1. However, the present invention is not limited to this. The open state determination unit 143 may determine that the battery cover 120 is in the open state when the period during which the voltage of the first terminal or the second terminal is equal to or lower than the threshold value th1 continues for a predetermined period or more. In this way, when the voltage of the first terminal or the second terminal momentarily becomes equal to or lower than the threshold value due to a factor other than the open state, such as vibration, it is not necessary to determine that the battery cover 120 is in the open state, and the reliability of the open state determination can be improved.

The threshold value th1 used to determine the open state is preferably set to be smaller than the threshold value th2 used for the battery level notification that notifies the user that the battery level is low. As shown in FIG. 6, by setting the threshold value th1 to be smaller than the threshold value th2 used for the battery level notification, erroneous determination due to a voltage drop in the main battery 151 can be prevented. The threshold value th1 used to determine the open state is preferably set to be larger than 0. By setting the threshold value th1 to be larger than 0, the open state determination unit 143 can output the determination result to the RTC unit 144 before it becomes inoperable.

The open state determination unit 143 may also determine that the battery cover 120 is in the open state when the lock unit 121 is in the unlocked state and the voltage of the first terminal or the second terminal is equal to or lower than the threshold value. In this way, the reliability of the open state determination can be further improved. This is because, in practice, the battery cover 120 is in the open state only when the lock unit 121 is in the unlocked state, and the battery cover 120 cannot be in the open state when the lock unit 121 is in the locked state. For example, it becomes possible to distinguish between a voltage drop caused by a break in the power supply line and a voltage drop caused by the battery cover 120 being in the open state.

In addition, in the above embodiment, the device body 110 has a first terminal connected to one of the two terminals of the battery, and the battery cover 120 has a second terminal connected to the other of the two terminals of the battery. However, the present invention is not limited to this, and can also be applied to cases where both the first terminal and the second terminal are on the device body 110 side (for example, in the case of the configuration described in Figures 1A and 1B), or where both the first terminal and the second terminal are on the device body 110 side.

In essence, all that is required is a device main body having an electrical circuit for recording an electrocardiogram, a battery cover that can be attached to the device main body so as to be freely opened and closed, a power supply line that supplies the battery power supply voltage to the electrical circuit of the device main body when the battery cover is in a closed state, an open state determination unit that detects the voltage of the power supply line and determines that the battery cover is in an open state when the voltage is equal to or lower than a threshold value, and a recording unit that records as a log the time when the open state determination unit determines that the battery cover is in an open state. In the above-mentioned embodiment, the terminal voltage is detected as an example of the voltage of the power supply line.

In addition, in the above embodiment, the present invention has been described as being applied to a Holter ECG recording device, but the present invention is not limited to this and can be widely applied to medical devices that have a device body and a battery cover. It is particularly useful for medical devices that require miniaturization and weight reduction, such as portable medical devices.

The present invention is widely applicable to medical devices that have a device body and a battery cover and record a log of the open state of the battery cover.

REFERENCE SIGNS LIST 10, 110 Device body 11, 12 Engagement hole 13, 111 Display unit 14, 112a Event button 20, 120 Battery cover 21, 22, 114, 115, 126 Engagement claw 23 Battery holder 24 Protrusion 100 Holter electrocardiogram recording device 112b Enter button 113 Battery storage unit 116, 124, 125 Engagement groove 117 Terminal 121 Lock unit 122 Rotating shaft 123 Terminal unit 131 CPU
132 ECG connector 133 ECG section 134 NAND flash memory section 135 SD card section 136 Buzzer section 137 Serial communication connector 138 Acceleration detection section 141 Battery terminal 142 DC-DC conversion section 143 Open state determination section 144 RTC section 151 Main battery 152 Backup battery

Claims (8)

A device body having an electric circuit for recording an electrocardiogram;
a battery cover that is attached to the device body so as to be freely opened and closed;
a power supply line for supplying a battery power supply voltage to an electric circuit of the device body when the battery cover is in a closed state;
an open state determination unit that detects a voltage of the power supply line and determines that the battery cover is in an open state when the voltage is equal to or lower than a threshold;
a recording unit that records, as a log, a time at which the open state determination unit determines that the battery cover is in an open state;
A medical device having the following: the device body has a first terminal connected to one of the two terminals of the battery,
the battery cover has a second terminal connected to the other of the two terminals of the battery,
the power supply line supplies a power supply voltage of the battery to an electric circuit of the device body when the battery lid is in a closed state and both of the first terminal and the second terminal are connected to two terminals of the battery;
the open state determination unit detects a voltage of the first terminal or the second terminal as a voltage of the power supply line.
2. The medical device of claim 1. the open state determination unit determines that the battery cover is in an open state when a period during which the voltage of the power supply line is equal to or lower than the threshold continues for a predetermined period or longer.
3. A medical device as claimed in claim 1 or 2. The threshold value is smaller than a threshold value used for a battery remaining amount notification that notifies the user that the remaining amount of the battery is low.
A medical device according to any one of claims 1 to 3. The threshold is greater than 0.
A medical device according to any one of claims 1 to 3 . The recording unit is configured to be driven by a backup battery separate from the battery.
A medical device according to any one of claims 1 to 5. The battery cover further includes a locking portion for locking the battery cover.
the open state determination unit determines that the battery cover is in an open state when the lock unit is in an unlocked state and the voltage of the power supply line is equal to or lower than the threshold value.
A medical device according to any one of claims 1 to 6. The medical device is a Holter electrocardiogram recording device.
A medical device according to any one of claims 1 to 7.

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