JPH0423305Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention is a high-voltage device for defibrillation equipment that is charged from a high-voltage generation circuit in order to apply high voltage in pulses to paddles attached to the heart. It is related to capacitors.

[Problems that conventional technology and ideas try to solve]

In this type of capacitor, the electrodes are of a metal foil type, and therefore terminals of a lead wire insertion type tab structure are exclusively used. For this reason, the shape of the high-voltage capacitor is bulky, and stress is applied to the lead wire when discharging a large current, resulting in problems in terms of lifespan. Therefore, in order to solve these problems, it may be possible to use a metallized plastic film capacitor in which the electrodes are formed of a vapor-deposited layer and the lead wires are derived from metallized parts at both ends where the film is wound. As for high pressure and large capacity, the above-mentioned method is advantageous in terms of manufacturing, so it has not been used at present. In addition, in this case, because the lead wires are derived from the metallic contact portions on both end faces, tanδ can be reduced, but it was also confirmed that when the insulation breaks down, short circuit current flows intensively and the explosion noise becomes louder, which poses a problem for the application. has been done.

In view of this, the object of the present invention is to provide a high-voltage capacitor made of a metallized plastic film capacitor that is suitable for defibrillation devices.

[Means and actions for solving problems]

In order to achieve this objective, the present invention houses a plurality of capacitor elements in which a metallized plastic film is wound and both end faces are treated with metallicon in a common case. The metallic contact portions on both end faces of each capacitor element are connected to a pair of capacitor terminals led out from the case, and a resistance at least equal to the internal resistance of the capacitor element itself is established between the metallic contact parts on at least one end face. A resistor having a resistance value of .

[Effect]

As a result, the capacitor capacity corresponds to each element connected in parallel, and if one of the capacitor elements is short-circuited due to dielectric breakdown due to the intervening resistor, the charging current of the other capacitor element will be discharged through the intervening resistor.

[Example of idea]

FIG. 1 shows a high voltage capacitor 10 for a defibrillator according to an embodiment of the present invention. This capacitor is
By winding metallized plastic films 1a and 1b, on which a metal layer 2 of aluminum, for example, is vapor-deposited, with a protective film 3 interposed so as to create non-deposited parts at the left and right ends (FIG. 2), four It is composed of a capacitor element 11. Both side end faces of each element are coated with metallized silicone 12, resistance wires 13 are soldered to each end face of one end, and conducting wires 14 are soldered to each end face of the other side and connected in parallel to each other. These four capacitor elements 11 are enclosed in a case 15 filled with insulating oil and surrounded by a press board 16. Each resistance wire 13 is connected to one 17 of a pair of terminals 17, 17a formed on the upper surface of the case 15, and one conducting wire 14 is connected to the other terminal 17a from the parallel connection portion.

Each capacitor element 11 has a capacitance of, for example, 10 μF.
The battery is configured to have a withstand voltage of 10 kV, and an internal resistance value between the metallic contacts 12 on the end faces to be approximately several Ω, which is smaller than the biological resistance of approximately 50 Ω during discharge. The resistance value of each resistance line 13 is set to be approximately the same as each of the above-mentioned internal resistances of the capacitor element 11.

FIG. 3 shows the circuit configuration of a defibrillator using this capacitor 10.
0 and a high voltage capacitor circuit 2 composed of, for example, one capacitor 10 charged with the high voltage.
1, a paddle 22 attached to the heart, and a switch 24 that applies a charging high voltage to the paddle through an inductance 23.
Charging abnormality detection circuit 2 that detects a sudden change in the charging voltage or charging current of the high-voltage capacitor circuit 21 due to a short circuit due to dielectric breakdown of the capacitor 10
5, a notification means 26 for notifying an abnormality with a sound, a lamp, etc. in response to the detection signal, and a switch circuit 27 for interrupting the supply of high voltage to the high voltage capacitor circuit 21 in response to the detection signal. Attached.

When performing stimulation operation, first the high voltage generation circuit 2
The high voltage capacitor circuit 21 is charged from zero. After charging is completed, when the switch 24 is turned on, a pulsed high voltage shaped by the inductance 23 is applied to the paddle 22 due to discharge of the high voltage capacitor circuit 21.

If any element 11 of the high-voltage capacitor 10 breaks down during such a high-voltage charging/discharging process, a short circuit occurs between the terminals of that element, and a short-circuit current flows from other elements as well. At that time, the charging voltage suddenly drops faster than normal charging from the high voltage generating circuit 20 and discharging to the paddle 22, or the charging current from the high voltage generating circuit 20 rapidly increases, and the charging abnormality detection circuit 25, such a sudden change is detected. As a result, the notification means 26 issues an alarm, and the switch circuit 2
7 operates to interrupt the high voltage supply from the high voltage generating circuit 20. When this dielectric breakdown occurs, a short circuit current flows from other capacitor elements 11 through the resistance wire 13, so that the loud noise is reduced compared to the conventional case where only one capacitor element 11 is used. In addition, since a broken connection can be reliably detected, safety problems caused by the self-healing properties of metallized plastic films are also eliminated.

In the above embodiments, the number of elements in the capacitor can be arbitrarily set depending on its capacity, ease of manufacture, allowable explosion noise, etc. The additional resistors may be interposed between the metallic contacts on both end faces of the capacitor element, and the number of additional resistors may be reduced by one than the number of elements, as shown in FIG. The intervening resistance value needs to be at least as large as the internal resistance of each capacitor element from the perspective of reducing explosive noise, but it may be made larger if there are no problems with energy loss or discharge time constant to the paddle. The invention also applies to other types of metallized plastic films, such as single-sided deposition.

[Effect of idea]

As described above, according to the present invention, the size can be reduced by using a metallized plastic film, and by dividing into multiple elements, the number of turns of the thin metal layer can be reduced in the manufacturing process, making manufacturing easier. It also improves reliability after manufacturing.
Furthermore, at the time of dielectric breakdown, short-circuit discharge from other capacitor elements is carried out through the additional resistor, thereby avoiding concentrated discharge and reducing explosion noise. In short, the advantages of metallized plastic film are utilized, and the problems that may arise when metallized plastic film is used in defibrillators are also eliminated.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view of a high-voltage capacitor for a defibrillator according to an embodiment of the present invention;
The figure is a perspective view of the metallized plastic film of the same embodiment, FIG. 3 is a diagram showing the circuit configuration of a defibrillator using the capacitor of the same embodiment, and FIG. 4 is a schematic diagram of a high-voltage capacitor according to another embodiment. FIG. 3 is a diagram showing the configuration. 1a, 1b...metalized plastic film,
2...Metal layer, 10...High voltage capacitor, 11...
...Capacitor element, 12...Metallicon, 13...
...Resistance wire, 14... Conductor wire, 17, 17a... Terminal.

Claims (1)

[Claim for Utility Model Registration] A high-voltage capacitor for a defibrillator that is charged with high voltage from a high-voltage generating circuit in order to supply high voltage to a paddle attached to the heart that stimulates with electrical pulses. A plurality of capacitor elements having metallized plastic films wound thereon and both end faces treated with metallicon are housed in a common case, and the metallicon portions on both end faces of each of the capacitor elements are connected to a pair of capacitors drawn out from the case. A high-voltage capacitor, characterized in that a resistor is connected to each terminal and has a resistance value at least equal to the internal resistance of the capacitor element itself between each of the metallicon parts of the end face on at least one side.