JP3174213B2 - Percutaneous charging device for biological implantable devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transcutaneous charging device for externally charging an internal battery for a biological implantable device such as a cardiac pacemaker.

[0002] A primary battery having a large amount of energy per volume is used as a device for supplying power to a control circuit or the like of a biological implanting device such as a cardiac pacemaker.
However, since the primary battery cannot be charged, when the battery reaches the end of its life, re-implantation of a device filled with a new battery is required, and the mental and physical burden on the patient is great. For this reason, introduction of a rechargeable secondary battery is desired.

[0003] However, in order to perform percutaneous charging of a living body implanted device having a secondary battery from outside the body, it is necessary to determine whether or not to continue the charging operation based on the charging status of the secondary battery. Information needs to be transmitted outside the body.

[0004]

2. Description of the Related Art Conventionally, in order to implement such charging control, an AC electromagnetic field is continuously generated from the outside of the body by an inverter circuit and transmitted to the inside of the body, and the rechargeable battery is charged from the inside of the body. Monitoring information and the like are always transmitted to the extracorporeal device by telemetry.

[0005] Then, based on monitoring information by telemetry such as the voltage of a secondary battery, an alternating electromagnetic field for charging is generated from the outside of the body and transmitted to the inside of the body to perform a charging operation.

[0006]

In the conventional apparatus as described above, the transmission of an AC electromagnetic field from the outside of the body for charging and the transmission of telemetry monitoring information from the inside of the body are performed simultaneously.

However, during the power transmission operation, the intensity of the electromagnetic field for charging is very large, so that the telemetry electromagnetic field when information such as monitoring information of the secondary battery is transferred to the outside of the body by telemetry is transmitted by the transmission electromagnetic field. Receive strong interference from the world.

[0008] As a result, errors occur in transcutaneous transfer information by telemetry, correct charging control of the secondary battery cannot be performed, and the battery itself and other electronic circuit components are destroyed due to overcharging of the secondary battery. There was a danger of closing.

SUMMARY OF THE INVENTION Accordingly, the present invention provides a transcutaneous charging system for a biological implantable device which can accurately extract charge monitoring control information from a battery implanted in a body without being disturbed by an alternating electromagnetic field when charging the battery. It is intended to provide a device.

[0010]

In order to achieve the above object, a transdermal charging device for a living body implantable device according to the present invention is provided in a living body for supplying electric energy to a device implanted in the living body. A battery 53 to be implanted and a transcutaneous charging means 1 for generating an AC electromagnetic field outside the body for charging the battery 53 in the living body and percutaneously transmitting power to the battery 53
0, 20; charging status monitoring means 54, 56 for monitoring the charging status of the battery 53 in the living body and transmitting the charging monitoring information to the outside of the body percutaneously; Percutaneous transdermal device for a living body implantable device having charge control means 34 and 35 for receiving the charge monitoring information sent from the outside of the body and controlling the operation of the transdermal charge means 10 and 20 according to the content of the signal. In the charging device, the percutaneous charging means 10 and 20 intermittently generate an AC electromagnetic field for charging the battery 53, and the charging state monitoring means 54 and 20 during a time period when the AC electromagnetic field is not generated. 56
And transmission / reception of charge monitoring information between the charge control means 34 and 35.

If the electromotive voltage of the battery 53 does not reach the predetermined voltage as a result of monitoring by the charging status monitoring means 54, 56, the charging control means 34, 35 Intermittently generate an alternating electromagnetic field,
When the electromotive voltage of the battery 53 reaches a predetermined voltage, the transdermal charging means 10 and 20 may stop generating an AC electromagnetic field.

[0012] If the electromotive voltage of the battery 53 does not reach the predetermined voltage as a result of monitoring by the charging status monitoring means 54 and 56, the charging control means 34 and 35 determine the charging current value and the predetermined value. The magnitude of the AC electromagnetic field may be controlled so that the charging current value becomes the above-described predetermined value according to the magnitude of the difference between the two.

Further, the charging status monitoring means 5
Alarm monitoring means for issuing an alarm when the charging current for the battery 53 does not reach a predetermined value as a result of monitoring by the monitoring units 4 and 56 may be provided.

[0014]

The transcutaneous charging means intermittently generates an AC electromagnetic field for charging the battery inside the body outside the body, and the charging status monitoring means and the charge control during a time period when the AC electromagnetic field for charging is not generated. Transmission and reception of the charge monitoring information is performed with the means. Therefore, transmission and reception of the charge monitoring information is not affected by the charging AC electromagnetic field.

[0015]

An embodiment will be described with reference to the drawings. FIG.
FIG. 1 is an overall configuration diagram of a transdermal charging device for a biological implantable device.

Reference numeral 1 denotes a primary battery as a power source for a charger placed outside the body for percutaneously charging a living body implanting device (for example, a cardiac pacemaker). 10 is to set the strength of the AC electromagnetic field for transdermal charging in accordance with the voltage or the like of the secondary battery 53 used in the living body implanting device,
This is a voltage transformation circuit for transforming (stepping up / down) the voltage of the primary battery 1 outside the body, and includes an inductance 11, a switching transistor 12, a diode 13, a smoothing capacitor 14, and the like.

In order to obtain a desired DC voltage by performing a step-up or step-down operation in the transformer circuit 10, the pulse width of a control pulse applied to a gate for turning on the switching transistor 12 may be adjusted.

Reference numeral 20 denotes an inverter circuit for generating an AC electromagnetic field for transcutaneous charging, which is basically constructed by combining four switching transistors 21 to 24 in series and in a bridge.

In the inverter circuit 20, the DC voltage supplied from the transformer circuit 10 is applied to two switching transistors 21 to 24 (21 and 24 and 22 and 2
3) An AC voltage is generated between A and B in the figure by controlling the conduction at different times in combination.

To change the amplitude of the AC voltage or stop the generation, the two sets of switching transistors 21 and
This can be implemented by changing the time width of the control pulse applied to the gates of the gates 4 and 22 and 23 or by stopping the applied control pulse. 25 is a smoothing capacitor.

Reference numeral 31 denotes a power transmission coil for transmitting power to a device implanted in a living body based on the AC voltage generated by the inverter circuit 20, and the coil specifies the radiation directivity of the electromagnetic field. It is braided into a ferrite core or the like to increase its strength.

Reference numeral 100 denotes a living tissue such as a muscle or a fat interposed between the skin surface of the living body and the device implanted in the living body (hereinafter, referred to as "living body skin 100").

Reference numeral 51 denotes a case of a living body implanting device (for example, a cardiac pacemaker), which is made of a metal such as titanium or a metal alloy, and whose surface is covered with a polymer resin or the like so as not to cause inflammation in the living body. Is done.

Reference numeral 52 denotes a power receiving coil mounted in the implantable device case 51. The power receiving coil 52 transmits an AC electromagnetic field for charging from the extracorporeal power transmitting coil 31 through the skin 100 of the living body and the implantable device case 51. Receive power.

Reference numeral 60 denotes a power receiving rectifier circuit, which is composed of four diodes 61 to 64 and a smoothing capacitor 65 combined in a bridge shape. The AC voltage received by the power receiving coil 52 is full-wave rectified and rippled. Is removed.

Reference numeral 53 denotes a chargeable secondary battery that supplies electric energy for operation and control to the implanted device, and is charged by a DC output of the power receiving rectifier circuit 60.
As a charging method, either constant voltage charging or constant current charging may be adopted.

Reference numeral 54 denotes when the secondary battery 53 is charged.
It is a current monitoring resistor having a known resistance value for monitoring a charging current. Since the internal impedance of the secondary battery 53 generally changes depending on the charging rate, in order to perform constant-current charging on the secondary battery 53, it is necessary to constantly and appropriately change the intensity of the AC electromagnetic field for charging. . The charging current value at this time can be converted from a potential difference generated between both ends of the current monitoring resistor 54.

Reference numeral 55 denotes a load including a control circuit of the implanted device and the like, and electric power for operating the load is supplied from the secondary battery 53. 56 measures the potential difference generated between both ends of the current monitoring resistor 54 having a known resistance value as the voltage of the secondary battery 53 and the charging current at the time of charging, and the voltage of the secondary battery 53 is determined based on those values. This is a charge monitoring control circuit for determining whether or not a predetermined value has been reached and generating a control signal for determining whether to continue or stop the charging operation.

Reference numeral 57 denotes a telemetry transmission circuit for modulating and transmitting a carrier signal in order to transmit output information from the charge monitoring control circuit 56 to a charger outside the body by telemetry. Reference numeral 58 denotes a transmitting antenna coil for transmitting charging monitoring control information for telemetry from the implanted device to the receiving antenna coil 32 outside the body.

The transmission signal from the charge monitoring control circuit 56 is
The signal is transmitted from the transmitting antenna coil 58 to the outside of the body via the implantable device case 51 and the skin 100 of the living body, and is received by the telemetry signal receiving antenna coil outside the body. 33
Is a telemetry receiving circuit for demodulating the received telemetry signal and converting it into charging monitoring control information.

Numeral 34 denotes an inverter control circuit for controlling the operation of the inverter circuit 20. When charge management information is received, for example, when a telemetry signal indicating that charging is completed and charging should be stopped is received, the inverter control circuit 34 controls the operation of the inverter circuit 20. In order to stop the operation of the twenty switching transistors 21 to 24, a control pulse applied to the gate is output so as to make it non-conductive.

Reference numeral 35 denotes a charge control circuit, which is a gate for increasing the conduction period of the switching transistor 12 of the transformer 10 when a telemetry signal indicating that the charge current should be further increased is received as charge monitoring control information. Control the pulse applied to.

Reference numeral 36 denotes a display / alarm / operation circuit for monitoring charge monitoring information on the secondary battery 53 of the implanted device by the external chargers 10 and 20, and for performing various necessary operations.

The transdermal charging device for a living body implanted device according to the present invention is configured as described above, and an AC electromagnetic field for charging is generated by the inverter circuit 20. Thus, the generation is controlled intermittently in a so-called burst in units of a certain period.

FIG. 2 shows an example of the AC voltage generated by the inverter circuit 20. During a period of T ₀ (for example, 1 second), an AC voltage of, for example, 20 KHz is continuously generated in a burst manner, and the next T ₁ is generated. During the period (for example, 0.3 seconds), the generation of the AC voltage is stopped, and T ₀ and T ₁ are alternately repeated.

Such an AC voltage is applied to the power transmitting coil 31 on the outside of the body, is received by the power receiving coil 52 on the inside of the body via the skin 100 of the living body and the implantable device case 51, and is generated by the received AC electromagnetic field. AC voltage is converted into direct current by the power receiving rectifier circuit 60 incorporated in the implanted device, charging a period rechargeable battery 53 of the T _0.

The charging current value to the secondary battery 53 by measuring the voltage across the period to the current monitoring resistor 54 of T _0, keep temporarily holds such a result is not shown register. The voltage of the secondary battery 53 can be easily measured by measuring the voltage between the terminals of the secondary battery 53.

The monitoring of the state of charge of the secondary battery 53 is performed by a charge monitoring control circuit 56. Transmission to the extracorporeal device of the monitoring information, the generation of strong AC electromagnetic field is carried out in a period of T ₁ which is stopped due to the charge.

Further, the charge monitoring control circuit 56 is provided with a control signal for stopping the charging operation from the device outside the body when the secondary battery 53 is sufficiently charged and the charging is completed. A circuit to be generated is included.

[0040] In the present apparatus, such a strong alternating electromagnetic field for charging is generated by the period of T _0, in a period of T ₁ generation of the alternating electromagnetic field has stopped, the charge monitoring control information The implantable device controls the telemetry transmission to the outside of the body.

Therefore, the strong AC electromagnetic field for charging interferes with the telemetry signal having a small signal level to cause an error in the telemetry signal or adversely affect the operation of the transmission / reception circuit of the telemetry signal and the operation of the charge control signal generation circuit. And a safe charging operation is performed.

FIG. 3 shows that, in the inverter circuit 20, T
₀ in order to stop the generation of the period successive periods alternating voltage of T ₁ mixture was allowed to generate an AC voltage of, illustrates an example of a charging AC voltage generation control circuit provided to the inverter control circuit 34.

Here, the charge finger whose charge control information is "1"
Is designated, the first differentiating circuit 71₀of
T when output becomes "1" only during period₀Activate timer 72
You. T ₀Timer 72 starts counting from the start₀Period of
It outputs "1" and then becomes "0".

The output of the T ₀ timer 72 includes a first inverted logic gate 73 via a second differentiating circuit 74, the output only during the period of T ₁ is inputted to the T ₁ timer 75 becomes "1".
As a result, when the output of the T ₀ timer 72 changes from “1” to “0”, the T ₁ timer 75 is started, outputs “1” during the T ₁ , and then becomes “0”.

The output of the T ₁ timer 75 is fed back to the first differentiating circuit 71 for starting the T ₀ timer 72 via the second inversion logic gate 76 and the AND gate 77 of the charge control information. As a result, when the charging instruction is specified, a period of T ₀ from T ₀ timer 72 is "1", the period of the subsequent T ₁ output is generated to repeat a "0".

The output of the T ₀ timer 72 is supplied to two sets of AC voltage generation control signals whose phases are approximately １ ／ different from each other in order to generate an AC voltage in the inverter circuit 20, and AND gates 78 and 79 to perform AND logic processing Then, a gate control signal for the two switching transistor pairs 21, 24 and 22, 23 configured in a bridge-like manner is generated and transmitted to the inverter circuit 20.

As a result, an AC electromagnetic field is continuously generated in the inverter circuit 20 for the period T ₀ , and the AC electromagnetic field is continuously generated for the period T _1.
During this period, the generation of the AC electromagnetic field is stopped, and this state is repeated.

The generation of the period T ₀ for continuously generating the AC electromagnetic field does not necessarily need to be performed by a timer such as a monostable multivibrator, and the generation cycle of the AC voltage is determined based on the cycle of the AC voltage. The present invention may be implemented by means of calculating and controlling with a counter.

FIG. 4 shows a charge monitoring control circuit 56 for transmitting the charge monitoring control information of the secondary battery 53 from the inside of the body to the outside of the body during the suspension period of the AC electromagnetic field generated for charging from the outside of the body. 1 shows an example of a charge monitoring control information transmission signal generation circuit provided in the first embodiment.

The charging AC electromagnetic field from outside the body is received by the power receiving coil 52 inside the body shown in FIG.
An AC voltage is induced there. Then, the AC voltage is rectified by the power receiving rectifier circuit 60, and charges the secondary battery 53 via the smoothing filter constituted by the smoothing capacitor 65 and the current monitoring resistor 54.

However, the DC voltage rectified by the power receiving rectifier circuit 60 includes four rectifying diodes 61.
Due to the characteristics of .about.64 and slight imbalance in circuit mounting, minute rectified noise corresponding to the positive and negative polarity of the AC voltage is superimposed as a ripple.

Therefore, the circuit shown in FIG. 4 uses the rectified voltage as an input, amplifies, for example, only the positive component of the ripple superimposed thereon, and integrates the time to obtain the ripple associated with the reception of the charging AC electromagnetic field. The charging AC voltage generation period detection circuit 80 that sets the output to “1” during the period (T ₀ ) during which the charging occurs, and the charge monitoring control information during the period T ₁ after the continuous generation of the charging AC electromagnetic field is stopped. The transmission timing determination circuit 90 determines the transmission timing for telemetry transmission outside the body.

In the charging AC voltage generation period detecting circuit 80, the rectified voltage input terminal is connected to the capacitance 8 connected in series.
1 is connected to the base of the first transistor 82.

As a result, the DC component of the rectified voltage is removed, and the ripple component superimposed on the rectified voltage is reduced by the transistor 8.
2 is input to the base. Note that a DC bias voltage obtained by dividing the difference between the power supply voltage of the circuit and the ground potential by two resistors is applied to the base of the transistor 82.

The output of the collector of the transistor 82 in the first stage is obtained by inverting and amplifying the ripple applied to the base, and
The signal is input to the base of the transistor 83 at the stage. 2
A DC bias potential is applied to the base of the transistor 83 of the first stage by dividing the power supply voltage by a resistor having a higher resistance than the collector load resistance of the transistor 82 of the first stage, and the output of the transistor 82 of the first stage is applied thereto. Are superimposed and input.

In the collector output of the transistor 83 in the second stage, the inverted ripple output amplified and applied to its base is further inverted and amplified. That is, 2
The collector output of the transistor 83 at the stage has a voltage amplitude obtained by amplifying the ripple applied to the base of the transistor 82 at the first stage by a factor corresponding to the product of the amplification factors of the transistors 82 and 83.

The polarity of the output is the same as the polarity of the input ripple, but since the emitter potential of the second-stage transistor 83 is ground, no negative potential is generated. That is, under an appropriate DC bias supplied to the base, an output in which only the ripple corresponding to the positive polarity is amplified can be obtained as the collector output.

This output is an output of positive polarity according to the generation period of the AC electromagnetic field while the AC electromagnetic field is generated intermittently, and no ripple occurs while the AC electromagnetic field is not generated. Therefore, no output corresponding to the ripple is generated.

A resistor 84 and a capacitance 85 are connected in series to the collector of the transistor 83 in the second stage, and a circuit for detecting the potential due to the electric charge accumulated in the capacitance 85, that is, an integration circuit is provided. It is configured.

The resistor 84 and the capacitance 85 of the integrating circuit are
The integration constant determined by the product of the resistance value and the capacitance value is set to take a value sufficiently larger than the period of the intermittently generated AC electromagnetic field.

Accordingly, the output from the integrating circuit is "1" during the period (T ₀ ) in which the AC electromagnetic field is generated intermittently, and is output while the AC electromagnetic field is not generated. Since it is “0”, the AC voltage generation period can be detected.

The output of the AC voltage generation period T ₀ detected by the AC voltage generation period detection circuit 80 is input to the transmission timing determination circuit 90, and the inverted logic gate 91 and the differentiation circuit 92
Through, it is input to the delay pulse generating circuit 94 and the T ₁ timer 93.

Here, by the operation of the inverting logic gate 91 and the differentiating circuit 92, an appropriate time for executing a process of reading information from a register or the like (not shown) is set based on the end of the AC voltage generation period. Are set based on the output of the delay pulse generation circuit 94.

Since this period must be during a period (T ₁ ) during which a predetermined AC electromagnetic field is not generated, an AND gate is set so that the output of the T ₁ timer 93 is output during the period of “1”. 95 is performed.

As described above, the generation period (T ₀ ) of the charging AC electromagnetic field from outside the body is determined synchronously by the charging AC voltage generation period detection circuit 80, and the generation of the charging AC electromagnetic field is determined. after being stopped, charge monitoring control information stored in a register or the like at an appropriate time as determined by the transmission timing determining circuit 90 during the period T ₁ is read, the signal to be transmitted is generated by telemetry.

FIG. 5 is a diagram conceptually showing the relationship between the electromotive voltage of secondary battery 53 and the charging current of secondary battery 53. The state of the secondary battery 53 in the initial stage is a fully charged state. However, when the operation of the load is long, the charge stored in the secondary battery 53 is gradually discharged, and the secondary battery 53 is discharged.
The electromotive voltage of the device decreases. Therefore, for example, measurement of the electromotive voltage of the secondary battery 53 is performed every time a predetermined period elapses, and charging is performed when the discharge has progressed to a predetermined value or more.

FIG. 5 shows the relationship between the electromotive voltage of the secondary battery 53 and the charging current when the secondary battery 53 is charged at a constant voltage. In the initial stage of charging, the secondary battery 53 has been discharged, and the electromotive voltage of the secondary battery 53 has decreased. Therefore, the power supply voltage for charging the secondary battery 53 and the electromotive voltage of the secondary battery 53 are different. The difference is large and the charging current is large. However, as the degree of charging increases, the electromotive voltage of the secondary battery 53 sequentially increases, so that the difference between the power supply voltage and the electromotive voltage of the secondary battery 53 gradually decreases, and the charging current decreases.

FIG. 7 shows the relationship between the electromotive voltage of the secondary battery 53 and the charging current when the secondary battery 53 is charged with a constant current. Since the charging current is constant, the electromotive voltage of the secondary battery 53 increases as the degree of charging increases.

The point P in FIG. 5 is a point at which charging is completed. If charging is continued further, overcharging will occur, causing the risk of distortion of the characteristics of the secondary battery 53 itself and damage to other components.
This is a state where the charging operation is completed. The charging completion point can be determined based on the electromotive voltage of the secondary battery 53 and the like.

FIG. 6 shows the relationship between the progress of the degree of charge and the charge control information regarding the charge control of the secondary battery 53. The charging AC electromagnetic field from the outside of the body is transmitted in bursts every period T ₀ , and the secondary battery 53
Is charged. When the transmission period ends, the period of T ₁ is being stopped generation of alternating electromagnetic field, the power transmission stops.

During the period of T ₁ , the charge monitoring control circuit 56
Measures the electromotive voltage of the secondary battery 53, performs a comparison operation with a preset charging completion voltage, and outputs the result to the telemetry transmission circuit 57 for telemetry transmission as charge control information.

When the electromotive voltage of the secondary battery 53 is equal to or lower than the charging completion voltage, the charging control information becomes "1", and a charging instruction for continuously generating the charging AC electromagnetic field for the next period is issued. Is sent.

When the burst power transmission for charging is repeatedly performed to some extent and the electromotive voltage of the secondary battery 53 reaches the charging completion voltage, the charging control information becomes “0”, and after the next period, A signal indicating a charge stop instruction for stopping the generation of the charging AC electromagnetic field is transmitted.

The generation of the charge control information need not necessarily be performed by the charge monitoring control circuit 56 of the living body implanted device. The charge monitoring information such as the electromotive voltage of the secondary battery 53 is received outside the body by telemetry, Control circuit 3
4, etc., the charge control information may be generated.

FIG. 7 shows the relationship between the applied pulse output from the inverter control circuit 34 to the gates of the switching transistors 21 to 24 of the inverter circuit 20 and the output voltage of the inverter circuit 20 in response to the charge control information. ing.

When the inverter control circuit 34 receives the charge instruction information whose charge control information is “1”, the inverter circuit 2
The pulse applied to the gates of the two switching transistor pairs 21, 24 and 22, 23 combined in a bridge-like manner with a duty of approximately 0.5 has an inverter control circuit such that the transistor pairs are conductive complementarily to each other. 3
4 is output. As a result, the inverter circuit 20 outputs an AC voltage for charging intermittently in a burst manner.

When the inverter control circuit 34 receives the charge stop information whose charge control information is “0”, the inverter circuit 2
The inverter control circuit 34 controls the application of the pulse to the gates of the transistors 21 to 24 to be stopped so that both of the two switching transistor pairs 21 and 24 and 22 and 23 are non-conductive. Then, the inverter circuit 20 stops generating the AC voltage for charging.

FIG. 8 shows the comparison result of the charge current monitoring information of the secondary battery 53 obtained by comparing the potential difference generated at both ends of the current monitoring resistor 54 with a known resistance value with the potential corresponding to the predetermined charge current value. It is shown as digital information.

In the continuous burst charge period T ₀ , the potential difference generated between both ends of the current monitoring resistor 54 can be measured by, for example, a differential operational amplifier (not shown), and the result is determined by a predetermined value. Is compared with a potential corresponding to the charging current value.

FIG. 8 shows the comparison result as 3-bit digital information, and is an example in which MSB (Most Significant Bit) is used as a sign bit.

Here, when the charging current value is larger than the predetermined charging current value, it is set to “1”, and when it is smaller, it is set to “0”, and the other two bits are set to the difference from the predetermined charging current value. Is displayed in accordance with. These charge current monitoring information
Charging is telemetry transmitted to the extracorporeal a period of T ₁ which is stopped.

In order to charge the secondary battery 53 with a predetermined current value, the charging control circuit 35 uses a transformer circuit to increase or decrease the intensity of a burst-like AC electromagnetic field in the next period based on this monitoring information. 10 by controlling the conduction period of the switching transistor 12 of the
This is performed by changing the output voltage of 0.

In the example shown in FIG. 8, the case where the difference from a predetermined current value is set as 3-bit digital information as the monitoring information of the charging current is shown. If the positional relationship with the implanted device shifts and the charging current is significantly smaller than the current value expected in a certain range, the output voltage of the transformer circuit 10 is increased more than necessary so as to obtain a predetermined charging current value. This may adversely affect the living body, and may cause damage or malfunction of electronic circuit components.

Therefore, when the charging current monitoring information is less than the lower limit of the charging current, alarm instruction control information is generated, and the extracorporeal device is provided with means for displaying the information.
It is appropriate to stop the charging operation once, adjust the positional relationship between the power transmission coil 31 and the implanted device, and then perform the charging operation again.

FIG. 9 shows the relationship between the charging current lower limit value and the alarm control instruction information. The charge monitoring control circuit 56 compares the charging current value with the charging current lower limit value, and generates alarm control instruction information as “1” when determining that the charging current value is less than the charging current lower limit value. The information is transmitted to the telemetry transmission circuit 57.
The display / warning / operation circuit 36 on the outside of the body performs an alarm display based on the received alarm control instruction information.

The alarm control instruction information obtained by comparing the charging current value with the lower limit value of the charging current value does not necessarily need to be generated by the charge monitoring control circuit 56 of the implanted device, but may be generated outside the body.

[0087]

According to the present invention, in order to perform percutaneous charging on a battery implanted in a living body, an AC electromagnetic field is generated intermittently from the outside of the body, and AC power for charging is obtained. By transmitting the charge monitoring control information of the internal battery to the outside of the body while the generation of the electromagnetic field is stopped, and performing the charge control based on this information, the charge from the battery embedded in the body The monitoring control information can be accurately taken out without being disturbed by the AC electromagnetic field when charging the battery. As a result, since charging monitoring information and charging control information can be obtained without error when charging the battery implanted in the living body implanted device, there is an excellent effect that the charging operation can be performed safely.

If the constant voltage charging is performed based on the electromotive voltage of the battery, it is possible to determine whether to continue or terminate the charging only by the electromotive voltage of the battery. If the constant current charging is performed so that the charging current is constant, the charging current value does not become excessively large, so that there is no possibility that the quality of the battery deteriorates.

Further, by issuing an alarm when the charging current value does not reach the predetermined value, it is possible to know the positional deviation between the extracorporeal charging device and the implanted device and to prevent the adverse effect on the living body from occurring. it can.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an embodiment.

FIG. 2 is a diagram illustrating a charging AC electromagnetic field (voltage) of an embodiment.

FIG. 3 is a circuit diagram of a charging AC voltage generation control circuit according to the embodiment.

FIG. 4 is a circuit diagram of a charge monitoring control information transmission signal generation circuit according to the embodiment.

FIG. 5 is a diagram showing a relationship between an electromotive voltage and a charging current of the secondary battery of the example.

FIG. 6 is a diagram showing the relationship between the degree of charge of the secondary battery of the embodiment and charge control information.

FIG. 7 is a diagram illustrating a relationship between an output of an inverter control circuit (a pulse applied to a gate) and an output voltage of the inverter circuit with respect to charging control information according to the embodiment.

FIG. 8 is a diagram showing charging current monitoring information of the secondary battery of the example.

FIG. 9 is a diagram showing a relationship between a charging current lower limit value and alarm instruction control information according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Transformation circuit 20 Inverter circuit 33 Telemetry receiving circuit 34 Inverter control circuit 35 Charging control circuit 53 Secondary battery 54 Current monitoring resistor 56 Charging monitoring control circuit 57 Telemetry transmission circuit 60 Receiving rectifier circuit

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Mari Okazaki 1500 Inokachi, Nakai-machi, Ashigara-kami, Kanagawa Prefecture Inside the Cardiopacing Research Corporation Laboratory (72) Inventor Masafumi Majima 1500 Inoguchi, Nakai-cho, Ashigara-gun, Kanagawa Car Co., Ltd. Inside the Geopacing Research Laboratory (72) Inventor Katsuya Hirachi 1500 Inoguchi, Nakai-machi, Ashigarakami-gun, Kanagawa Prefecture Inside the Cardiopacing Research Laboratory Laboratory (72) Koji Kuwana 1500 Inoguchi, Nakai-cho, Ashigarakami-gun, Kanagawa Car Co., Ltd. In the Geopacing Research Laboratory (56) References JP-A-50-60085 (JP, A) JP-A-5-317433 (JP, A) JP-A-4-67732 (JP, A) JP-A-51- 133994 (JP, A) United States Huh 4275739 (US, A) United States Patent 4082097 (US, A) (58 ) investigated the field (Int.Cl. ^7, DB name) A61N 1/378 H01M 10/44 H02J 7/00 301

Claims (4)

(57) [Claims] 1. A battery implanted in a living body to supply electrical energy to a device implanted in the living body;
A transcutaneous charging means for generating an alternating electromagnetic field for charging the battery in the living body outside the body and transmitting the battery transcutaneously to the battery, and monitoring the charging status of the battery in the living body to Charging status monitoring means for transmitting the charge monitoring information to the body percutaneously; and receiving the charge monitoring information sent from the charging status monitoring means outside the body, and performing the percutaneous charging in accordance with the content of the signal. A percutaneous charging device for a biological implantable device having a charging control means for controlling the operation of the means, wherein the percutaneous charging means intermittently generates an AC electromagnetic field for charging the battery, and the AC electromagnetic field is A transcutaneous charging apparatus for a living body implantable device, wherein charging / receiving information is transmitted / received between the charging status monitoring means and the charging control means during a time period in which no charging occurs. 2. The charging control means intermittently generates an AC electromagnetic field in the transcutaneous charging means when the electromotive voltage of the battery does not reach a predetermined voltage as a result of monitoring by the charging status monitoring means. 2. The transcutaneous charging means stops generating an AC electromagnetic field when the electromotive voltage of the battery reaches a predetermined voltage.
The transdermal charging device for a biological implantable device according to the above. 3. The charging control means, if the electromotive voltage of the battery does not reach a predetermined voltage as a result of monitoring by the charging status monitoring means, according to the magnitude of the difference between the charging current value and the predetermined value. 2. The transdermal charging device for a biological implantable device according to claim 1, wherein the intensity of the AC electromagnetic field is controlled so that the charging current value becomes the predetermined value. 4. An alarm generating means for issuing an alarm when a charging current for the battery does not reach a predetermined value as a result of monitoring by the charging status monitoring means.
The transdermal charging device for a biological implantable device according to the above.