JPS61288852A - Cauterizing hemostatic apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a method for cautery using a means for detecting deterioration of a heating element.
Regarding own device.

[Prior Art] In recent years, endoscopes have become widely used, which allow diagnosis or treatment deep within body cavities by inserting an elongated insertion section without requiring an incision from the body wall side. Became.

In addition to the observation means, the endoscope described above is generally provided with a hollow channel through which a treatment instrument can be inserted, and various therapeutic procedures can be performed with a treatment instrument suitable for the therapeutic operation inserted through this channel. It looks like this.

By the way, there is a laser If coagulation device that coagulates by irradiating a laser beam as a means of hemostasis when removing VS in a body cavity, etc., but currently it is expensive, requires skill, and is dangerous. It's also big.

For this reason, a system has been developed that uses a heating probe that can be inserted into a channel and energizes a heating coil provided at the tip of the heating probe to coagulate the bleeding site against which it is pressed.

However, because the responsiveness of the rise and fall of the positive temperature for solidification is low, - the time until solidification is reached or the time until cooling after solidification is
Since the amount of heat conducted to the surrounding tissue increases, there is a drawback that the surrounding tissue other than the target area becomes necrotic.

For this reason, as disclosed in Japanese Patent Application Laid-Open No. 58-69556, an ablation method using a heating element with good heating and cooling response in a thermal ablation probe (heater probe) that can be passed through a channel is proposed. There is a hemostatic device.

The above conventional example uses a Zener diode or an electron avalanche diode as a heating element, and uses a small heat capacity (that is, a small volume and mass), so the power supplied to the heating element is controlled on and off. It is a convenient device because it has good thermal response during heating and cooling, has almost no drawback of causing necrosis of surrounding tissues, and can perform blood in only the desired area.

[Problems to be Solved by the Invention] However, in order to improve the thermal response of the above heating element, the amount of electricity consumed per unit time is very large compared to an element with a small heat capacity, and the temperature of the heating element is very large. The amount of increase is also very large, and there is a problem that deterioration of characteristics is unavoidable when used repeatedly under severe conditions that greatly exceed the maximum rating.

Therefore, when used repeatedly, the heat generation amount changes due to deterioration of the characteristics of the heating element, and when trying to treat the target area with heat generation ω, the actual heat generation amount will deviate from the set value. There is a drawback that treatment cannot be performed. In addition, if deterioration progresses, there is a risk of destruction during use.
Reliability problems arise, such as the need to interrupt treatment.

[Object of the Invention] The present invention has been made in view of the above-mentioned points, and is capable of detecting whether or not a heating element is within a permissible range.
It is an object of the present invention to provide a cautery hemostasis device that can perform hemostatic treatment by cauterization in an appropriate state at all times.

[Means and operations for solving the problem] This device includes a minute constant current circuit 15 that supplies a minute constant current to the Zener diode 13 as a heat generating element, and a minute constant current circuit 15 that supplies a minute constant current to the Zener diode 13 as a heating element. A characteristic detection circuit 17 consisting of a comparison circuit 16 for detecting whether the voltage of the Zener diode 13 is within a permissible range is provided to accurately detect deterioration of the characteristics, short circuit, or disconnection of the Zener diode 13.

[Embodiment] FIGS. 1 to 3 relate to an embodiment of the present invention, in which FIG. 1 shows the configuration of the main part of the embodiment, FIG. 2 shows the external appearance of the embodiment, and FIG. The figure shows a specific circuit configuration of a probe drive circuit in one embodiment.

As shown in FIG. 2, the cautery hemostasis device 1 according to one embodiment has an operation panel 2 on the sloped front surface, a power supply box 3, a connector receiver 4A at the lower front of the power supply box 3, Connector 5A to 4B.

An elongated heater probe 5 that can be detachably attached to the connector 5B, and a connector receiver 6A provided at the lower front of the power supply box 3.
It consists of a foot switch 7 equipped with a connector 7A that can be detachably attached to the body, a water supply tank 8 attached to the side surface, and a probe drive circuit 9 shown in FIG. 1 disposed inside the power supply box 3.

The heater probe 5 is inserted into the probe section 10 in order to energize the heating element housed in the distal end section 11 through a flexible probe section 10 with a small diameter that can be inserted into a hollow channel of an endoscope (not shown). A coaxial cable is inserted through the pipe, and a water supply channel is provided for supplying cleaning water. Therefore, the electric connector 5A on the proximal side of the heater probe 5
and the water supply connector 5B are attached to each connector receiver 4Δ, 4B of the power supply box 3, and the connector 7A of the foot switch 7 is also attached to the connector receiver U6Δ of the power supply box 3, and then the water supply (cleaning) switch of the foot switch 7 is attached. By pressing the side, the cleaning liquid in the water supply tank 8 is sent through the water supply channel and sprayed from the nozzle at the tip 11 of the heater probe 5 toward the affected area for cleaning. By pressing the side, it is possible to heat the heating element via the coaxial cable and perform medical treatment such as hemostasis on the area to which the distal end 11 is pressed.

Incidentally, the jetting amount of the washing water and the heating m of the heating element can be selected and set according to the affected area using setting buttons 2a and 2b provided on the panel 2.

In addition, since the power supply box 3 handles the electrical system and the water supply system, an intermediate chassis is installed between the power supply box 3 at the position indicated by the broken line A in FIG. In addition to ensuring safety by separating the water supply system and housing the water pump in a waterproof frame, the manufacturing process is also easy, as each prefecture can be worked on separately and then assembled to create a finished product. It is possible to do so.

By the way, the configuration of the main parts of the probe drive circuit 9 in one embodiment is as shown in FIG.

The probe drive circuit 9 includes a drive constant current circuit 12, a Zener diode 13 as a heating element to which a constant current is supplied by the drive constant current circuit 12, and a Zener diode 13 as a heating element to which a constant current is supplied by the drive constant current circuit 12. A comparison circuit 16 that supplies a small constant current to the Zener diode 13, captures the voltage on the cathode side of the Zener diode 13 in this state, for example, and compares it with a predetermined comparison voltage.
a characteristic detection circuit 17 consisting of;
The control circuit 19 receives the judgment output from the L-ED panel 20 and maintains the current operating state or activates the alarm circuit 18 to warn of deterioration depending on the judgment result. A calorific value detection circuit 21 and the like for detecting calorific value is provided.

By the way, the control circuit 18 has a control function related to determining the deterioration of the Zener diode 13, as well as the above-mentioned 1=setting button 2a of the panel 2.

In accordance with the operation details of 2b, the responding LED panel 20 is controlled to turn on or off, and the setting of the time constant parameter of the calorific value detection circuit 21 is controlled in accordance with the operation details.

The Zener diode 13 has a Zener voltage V, for example.
A type with Z of approximately 20 [V] and a maximum rating of 5 [W1] is used. The anode of this Zener diode 13 is connected to the negative power supply end -VB (Vo=15 [V]. When in use, the cathode of the Zener diode 13 is connected to the drive constant current circuit 1 by the switch 14.
2 side, and its cathode is controlled by the constant voltage IC 12a of the drive constant current circuit 12! IJl[I will be connected to the emitter of transistor 12b via resistor 12r1.

On the other hand, during use and after use, the Zener diode 13 (the cathode thereof) is connected to the characteristic detection circuit 1 by the switch 14.
7 side, and approximately 10 [
The constant current of [mA] is compared with whether the cathode voltage of the Zener diode 13 (voltage relative to the negative power supply end potential -15 [V]) is, for example, 18 [V] or more with the comparator 16a flowing. The device 16b detects whether the voltage is within 25 [V], for example.

When the Zener diode 13 is within the allowable range, the outputs of both the comparators 16a and 16b are at a high level JL, the light emitting diode 17Cd is off, and a photocoupler is formed with the light emitting diode 17C and 17d. s
t-1" transistor 17Cp is off, and the potential of its collector is held at a high level. On the other hand, if the cathode voltage of the Zener diode 13 shifts to the lower or higher side and becomes out of the allowable range, both of the above comparisons occur. One of the outputs of the devices 16a and 16b becomes low level, and the light emitting diode 17C
d lights up, and the collector of the phototransistor 17Cp becomes low level. The low level potential of this collector is taken from the terminal C6 of the control circuit 19, and the alarm circuit 18 is designed to warn that the Zener diode 13 should be replaced.

A specific circuit configuration of the probe drive circuit 9 is shown in FIG.

The probe drive circuit 9 includes the drive constant current circuit 1 as described above.
Second, a Zener diode 13 as a heating element to which a constant current is supplied by the driving constant current circuit 12, and a switch 14 is switched by a relay 23 to detect deterioration of characteristics of the Zener diode 13. The micro constant current circuit 15 that flows a small constant current (for example, 10 volts) to the diode 13 side has characteristic deterioration or short circuit to determine whether the cathode potential of the Zener diode 13 is within the specified range while this constant current is flowing. Alternatively, in addition to the characteristic detection circuit 17 that detects whether the wire is disconnected, the alarm circuit 18 that operates in an abnormal state, and the heat generation amount detection circuit 21 that detects whether the total heat generation m has reached the set value, the Zener voltage (2) A heat generation control circuit 25 for controlling the heat generation temperature of the Zener diode 13 by using the temperature dependence in step 2, and a heat generation control circuit 25 that measures the time from the time when the heating current is passed through the Zener diode 13 and outputs the heat generation control circuit 25. A 31 o'clock circuit 27 constitutes a current cutoff means that can forcibly stop the output current by switching the switch 14 of the relay 23 with a signal, and each of these circuits is controlled by a control formed by a one-chip microcomputer. This is done in circuit 19.

The driving constant current circuit 12 is a constant voltage IC (for example, μA 7
23) Using 12a, control output terminal V of this IC 12a
A high voltage is applied to the base of the control transistor 12b.
The collector-emitter current of IJIII can be regulated to a predetermined current value, for example, 5401A or 400-8, depending on whether the heater probe 5 has a large diameter or a small diameter. For example, when a large-diameter heater probe 5 is attached, a resistor ra is connected to the connector 5A in this case, and this resistor ra allows the current flowing through the Zener diode 13 to be transferred to a small-diameter probe that is not provided with the resistor ra. It is possible to make it larger than the case.

In other words, this resistor ra reduces the combined resistance value of the emitter side of the control transistor 12b in the drive constant current circuit 12, which is the parallel connection value of the resistor 12r1 and the resistor ra, and increases the limiting current value.

Further, by adjusting this value using a variable resistor rb provided in the connector 5A, it is possible to set the current value to an appropriate current value even if there is some variation in the Zener voltage VZ of the Zener diode.

The constant voltage IC 12a is provided with a current limiting terminal CLIM, and a phototransistor 12CP1 forming a photocoupler is connected to this terminal OLIM.
When a light emitting diode (LED) 12Cc+t paired with the phototransistor 12Cpz emits light, it becomes conductive (turned on) and the restriction on the output current is released. A light emitting diode 120d that constitutes this photocoupler
The anode of l is connected to the (positive) power supply terminal through a resistor.
(+5 V), and its cathode is connected to the terminal C1 of the control circuit 19 via a buffer rat formed by an open collector inverter, and when the terminal C1- becomes high level, the LED 12Cdt emits light. be. Furthermore, when this terminal C1 becomes high level, the LED 15Cd connected to the buffer B1 emits light and the phototransistor 15CP provided in the minute constant current circuit 15 is turned on, thereby preventing the minute constant current function from being stopped. be.

Further, in the drive constant current circuit 12, when the phototransistor 12CP2 connected to the frequency correction terminal F is turned on, the output current of the drive constant current circuit 12 changes! ! It is now being cut off. This phototransistor 12 CL)
The LED 12Cc+2 paired with 2 is controlled by the output level of the terminal C2 of the control circuit 19.

By the way, in the control circuit 19, when the connector 5A is connected to the connector receiver 4A, the terminal C4 changes from high level to low level through the electrically connected terminals 5a and 5b of the connector 5A, and the heater puller 15
Control circuit 1 confirms that connector 5A is installed.
9, it can be detected. When this terminal C4 becomes low level, the terminal C1 is set to high level to light up the LED 15Cd, turn on the phototransistor 15Cp, and operate the minute constant current circuit 15. In this case, the terminal C5 in the control circuit 19 is at a low level, and the (NAND) gate G1
The transistor 01 is in an off state, and no current flows through the trenoid 23S of the relay 23. In this state, the switch 14 has conduction between its contacts 14a and 14a as shown by the solid line, so the minute constant current circuit 15 to Zener diode 1 via connector 5A of heater probe 5
For example, a minute constant current of 1QmA flows through the circuit 3.

The minute constant current circuit 15 converts the voltage of the load resistor 15r1 into the resistor 1 using an operational amplifier 15a.
5r2, and a predetermined current (
10+n8) is controlled to flow.

When the minute constant current flows, the potential of the cathode of the Zener diode 13 is detected by the characteristic detection circuit 17.

That is, the inverting input terminal of one comparator 16a in the comparison circuit 16 has +VB and -Ve connected to the resistor 16r+.

A predetermined voltage divided by 16r2 (relative to -Ve) -18
VL (+3V for zero level) is applied, and the cathode voltage of the Zener diode 13 is applied to the non-inverting input terminal. The other comparator 16
At b, non-inverting input $1VB, -Vo is connected to resistor 16
r3.16 A predetermined voltage divided by r+ (+ for -Vo
25V) VH is applied, and the above cathode voltage is applied to the inverting input terminal.

The output terminals of the upper two comparators 16a and 16b are LED17Cd.
and is connected to the power supply terminal +8 via a resistor. (Incidentally, the output terminals of both comparators 16a and 16b may not be connected directly, but may be connected through a resistor. Also, there is an input voltage difference between both input terminals of each comparator 16a, 16b. Comparators 16a and 16b when is too large (in the case of yri case, etc.)
It is also possible to connect forward and reverse protection (Zener) diodes connected in parallel. It can also be used in other circuit parts. ) Therefore, the Zener diode 13 has a length of 10 m as specified in the product standard.
A] has a regular Zener voltage (2) in the constant current state, the outputs of both comparators 16a and 16b will be high level, and the LED 17C (j will not emit light. However, the characteristics may deteriorate during use. etc., when the Zener voltage deviates from the normal Zener voltage Vz, both comparisons 1a16a,
One output of 16b becomes low level and LEDl 7C
d emits light. When this LEDl 7Cd emits light, the paired phototransistor 170E) is turned on and the terminal C3
goes from high level to low level. When this terminal C3 becomes a low level, the control circuit 19 detects an abnormality in the characteristics, avoids activation of the alarm circuit 18, and warns that the characteristics of the Zener diode 13 are not within the allowable range and should be replaced. Become. Furthermore, even if the replaced Zener diode 13 is not due to characteristic deterioration but deviates significantly from the specified value, the operation of the alarm circuit 18 makes it possible to know that the Zener diode 13 is not suitable.

By the way, the collector of the control transistor 12b is connected to the heating power supply @ via the resistor 25r1 (in the heat generation control circuit 25).
Ve (+15V) is connected to J3, this resistor 2
A voltage corresponding to the voltage drop due to 5r1 is applied to one input terminal of an operational amplifier (op-amp) 25a, and the other input terminal is held at the reference potential Vs. This operational amplifier 25
a amplifies the voltage between both input terminals (between them) by, for example, 3.9 times,
This output is sent to the multiplexer 26a of the calorific value detection circuit 26.
is applied to the input terminal of resistor 25r2. It flows through the emitter-collector of the transistor 25b and the resistor 25r3 to the negative power supply end -Ve.

This current causes the resistor 25r3 and the transistor 25b to
The potential at the connection point with the collector changes, and this potential passes through the resistor 25r4 to the (non-inverting) uIli of the constant voltage IC 12a.
By changing the voltage at the Il input terminal IN, this 1. The voltage at the IIH input terminal IN changes the output level of the control output terminal II to control the heating current. The feedback loop in this case is set to provide positive feedback. For example, resistor 25r1
When the current flowing through the transistor 25b increases, the potential at the inverting input terminal decreases, so the output level of the operational amplifier 25a increases, and the potential at the collector of the transistor 25b also increases, resulting in a constant voltage ICl2.
The potential at the control input terminal IN of a also rises, and the control output terminal Vl
The output level of Xst also increases, and control transistor 1
This is to increase the heating current flowing through 2b. In the opposite case, the heating current is reduced.

The control input terminal IN is connected to the standard voltage terminal V via a resistor 12r2.

On the other hand, the heat generation amount detection circuit 21 is connected to the control circuit 1.
By the digital signal output from the terminal (group) Cs of 9, the series resistor group 21r (4 resistors are shown in the figure) at the output end
A combination of short circuits is selected so that the series combined resistance value thereof can be selected. The integration time constant of the integration circuit can be selected by this combined resistance and the customer capacitor 21G connected between the inverting input terminal and the output terminal of the operational amplifier 21b.

Both ends of the capacitor 21G of the operational amplifier 21b constituting the above integration circuit are connected to the phoFET 21Cpt, and the LE
When D210dl emits 8 lights, both ends of the conde laser 210 are short-circuited, and the output of the operational amplifier 21b is output from the operational amplifier 21.
It is held at a level lower than the non-inverted input end of d.

When the terminal C2 of the control circuit 19 is set to a high level, the short circuit of the capacitor 21C is released and the integration operation is started.
The output becomes low level, and the LED 21Cd2 emits light. However, this LED21Cd2
When the phototransistor 21Cρ2 emits light, the paired phototransistor 21Cρ2
is turned on, and the terminal C7 becomes low level via the buffer B4. When this terminal C7 becomes low level, the control circuit 19 sets the terminal C2 to low level, for example.
Make LED12Cd2 emit light, and phototransistor 1
2CP2 is turned on to cut off the current output from the drive constant current circuit 12 to the load side.

By the way, when the contacts 14a and 14c4i of the switch 14 in the relay 23 are electrically connected and a minute constant current flows, and no short circuit or characteristic deterioration is detected, when the foot switch 7 is pressed, the terminal C8 changes from the high level. A trigger signal having a low level is output. This signal is applied to the trigger input terminal TRIG of a timer IC (for example, NE555) 27a forming the clock circuit 27, and from the rising edge of this trigger signal, the timer IC (for example, NE555) 27a
7a outputs a high-level signal from the output terminal OUT for a predetermined period of time (for example, 10 seconds) set by the resistor 27r and capacitor 27c, and this output signal is applied to the gate Gl, and the flip 70 knob 28 also outputs a high level signal. terminal CK
is applied to The flip-flop 28 is configured to output a low level signal, which is the output stop signal level, from the output terminal Q to the terminal C7 of the control circuit 19 via the buffer BS at the falling edge of the clock signal. In other words, since this output stop means is provided, even if an accident occurs such as when the heater probe 5 is disconnected while in use, the output from the timer circuit 27 will be activated via the flip 70 knob 28 after a predetermined period of time has elapsed. Since the terminal C7 is forced to a low level, the control circuit 19 sets the terminal C2 to a low level so that no heating current is output, just as if the integrating circuit by the heat generation detection circuit 21 was functioning normally. Make it. Also, even if one control circuit runs V due to external noise, the timer IC2
After a predetermined period of time has elapsed, the output terminal 7a becomes low level, so that the transistor Q1 via the gate 1-Gt is turned off, and the switch contacts 14a and 14b of the relay 23 are turned off, so that no power supply line is formed.

Therefore, the clock circuit 27 using the above-mentioned timer IC 27a
and a flip-flop 28 . which is operated by the output of the clock circuit 27 . Even if the control circuit 19 goes out of control, the switch contacts 14a and 14b in the power supply line of the relay 23 are turned off by the gate 01, so that current can be prevented from continuing to flow through the Zener diode 13. is the lecture.

When the terminal C7 becomes low level, if the roll circuit 19 to the controller 1 is functioning normally, the switch contacts 14a and 14b of the relay 23 are turned off, and the terminal C2 is turned off.
'a of the output current of the constant voltage IC 12a by setting it to low level.
This will activate the disconnection function.

Incidentally, the heat generation control circuit 25 is operated as follows.
- Controls the heat generation temperature of the door 13.

That is, in the Zener diode 13 as a heating element, its Zener voltage VZ exhibits a slight positive temperature dependence, and when heat is generated due to this temperature dependence, it depends on the state of heat dissipation at the tip 11 of the prong 5. The amount of temperature rise changes. This temperature rise becomes a current change, and this current change causes a voltage drop across the resistor 25r1, causing the operational amplifier 25
a, and the amount of current is controlled by a positive feedback loop including this operational amplifier 25a. In other words, if the temperature rise is large, the current is reduced to prevent the temperature at the tip 11 from rising too much, and if the heat dissipation is large, the amount of heat generated is increased to make it suitable for hemostasis. This allows it to be maintained at a certain temperature.

The operation of one embodiment configured in this manner will be described below.

When the connector 5Δ of the heater probe 5 is connected to the connector receiver 4A of the power supply box 3, the terminals 5a + 5b
The terminal C of the control circuit 19 becomes low level through the terminal C, and it is detected that the connector 5A is connected.

When this connection □ is detected, the control circuit 19
The terminal C1 is set to low level, the ED15Cd is turned off, the phototransistor 15Cp is turned off, the minute constant current circuit 15 is activated, and a minute current is supplied to the Zener diode 13 side through the terminal 4Hp. In this case. , the transistor Q1 is turned off when the terminal C5 becomes low level, so the relay 23 closes the switch contacts 14a and 1.
4G is on. Therefore, both comparators 16a, 16
b, it is detected whether the cathode potential of the Zener diode 13 is within the allowable level range and whether or not the heater probe 5 side is short-circuited, characteristic deterioration, short-circuiting, and disconnection.

(It is checked whether the Zener voltage VZ of the Zener diode 13 is within the allowable range, and if the Zener diode 13 at the time of this detection is short-circuited, it is detected by one comparator 16a, and if there is a disconnection, the other comparator 16b, and in addition to detecting the characteristics, the presence or absence of short circuits and disconnections is also detected.) When the load is released, the minute constant current circuit 15 connects the terminal 4Hp to which the Zener diode 13 is connected
The voltage between and -4Hp becomes almost 30[VE, and the emitter terminal of the turned-on phototransistor 15GE) is connected to the resistor 15rl so that it becomes almost 15V (15, IV).
, 15r2, etc. are the settings.

Therefore, if the voltage at the terminal 41-1p is ε, and the load resistance between both terminals 4HI) and -4HI) is R, then (30-VE)/Rtsrt =VE/R+ (
VE-15)/R15r2. KokoteRtsr
t, R, tsr2 are resistors 15r+ and 1, respectively.
The resistance value is 5r2. Therefore, when the Zener diode 13 is connected as the load, the Zener voltage V2 is 19.3 to 20.1 [9.
9 to 10.7 [mΔ], and its characteristics can be investigated under conditions equal to the conditions specified by the manufacturer's product specifications.

When the Zener diode 13 emits light, the apparent Zener voltage VZ increases.

In reality, the temperature is highest immediately after a large current is passed through heating. Therefore, when measuring after use, it is necessary to take into account the difference in Zener voltage Vz due to this increase in humidity.

If the room temperature is 25℃, the maximum temperature of the Zener tip during heating is 225℃, so the temperature rise up to this point is 20℃.
It is 0°C. The temperature coefficient of the Zener voltage ■2 of the Zener diode 13 used is 15 mV/''C, so 20
The increase in Zener voltage due to a temperature increase of 0°C is 15 mV x 200°C - 3V. Therefore, the threshold J' can be set by adding 3V to the upper limit of the normal selection range. In reality, there is an error in the operational amplifier 15a, so the voltage is 25V with -41-I P as the reference.
is set as the upper threshold. Regarding the lower threshold, since the humidity coefficient of the Zener voltage (2) is positive, it can be set to the lower limit of the Zener voltage Vz of the Zener diode 13 incorporated in the tip, but the lower limit should be 18V, including variations in the main body. . Therefore, Zener voltage due to heating or detection current flowing
A signal that is determined to be normal is output only to the boolobes 5 within the range of 18 to 25 V, including the temperature rise.

If there is no characteristic deterioration etc., when the foot switch 7 is pressed, the terminal C5 is set to high level, and the constant voltage IC 12a is set to high level.
At the same time, the relay 23 is connected to the switch contact 14.
A and 14b are turned on to form a power supply line, and a heating current flows to the Zener diode 13 side.

Further, the terminal C5 is set to a high level, and the terminal C8 is set to a low level for a period of, for example, several io+++s. This time may be formed by using the built-in 4 o'clock means of the control circuit 19, or by using a timer IC or the like. Further, at the rising edge when the terminal C8 changes from a low level to a high level, the output of the timer 1G 27a of the clock circuit 27 becomes high level for a predetermined period of time, and this output is applied to the other input terminal of the gate G1.

Therefore, the output of gate G1, that is, transistor Q1
The transistor Q1 is turned on when the base potential of
4b is turned on to form a power supply line.

After taking into account the delay operation time (several tens of meters) of the relay 23 (this time may also be realized using the clock built into the control circuit 19, or formed using a timer IC, etc.), the control circuit 19 sets the terminal C2 to high level, turns off the LED 12Cd2, turns off the phototransistor 12Cρ2, and turns off the Zener diode 1.
While making the current flow to the 3 side, the LED21Cd
t is turned off and the integrating circuit composed of the operational amplifier 21b and the like is activated.

The current flowing through the Zener diode 13 is the operational amplifier 25.
A positive feedback loop using d generates a large current (for example, about 1.5 A) when the current limit is released, and it is rapidly heated. After heating, a timer circuit (not shown) etc.
When m5 has elapsed, the elapsed signal is input to the control circuit 19, and the control circuit 19 sets the terminal C1 to a low level. When this terminal C1 becomes low level, LE0
12Cdl is turned off, and the current flows through the Zener diode 13 in the current limit state.

Since the voltage Vz of the Zener diode 13 has a temperature dependence, as the temperature rises, the current decreases, and this decrease is detected by the heat generation control circuit 25 and is controlled by the positive feedback loop. Temperature n is controlled to be regulated, and even if the state of heat dissipation at the distal end portion 11 changes, the temperature is maintained at a temperature suitable for hemostasis.

The current flowing through the Zener diode 13 is integrated by the integrating circuit via the multiplexer 21a, and when the preset heat generation m is reached, the output of the operational amplifier 21d becomes low level, the LED 21Cd2 lights up, and the phototransistor 21CP2 turns on. Then, the terminal C7 goes to the - level and an interrupt is generated.

Then, the control circuit 19 changes the signal level of the terminals C2 and C5 to low.

When the terminal -02 is set low, the 1-ED12Cd2 emits light, the phototransistor 12Cρ2 is turned on, and the heating current is not output from the drive constant current circuit 12. Furthermore, when the terminal C5 is set to the [■- level, one input terminal of the gate G1 is set to the low level, so the transistor Q1 is turned off, and the relay 23 is set to the switch contact 1.
4a and 14b are turned off so that no power supply line is formed.

In this way, heating is reliably stopped. Note that the output of the timer IC 27a becomes low level after a predetermined time.

The above operation occurs when the control circuit 19 works normally, and when the heater probe 5 is broken and current no longer flows, or the control circuit 19 goes out of control due to external noise etc. In this case, the output of the timer IC 27a becomes low level after a predetermined period of time has elapsed, and therefore, the transistor Q1 passing through the gate G1 is turned off in the same way as described above. Then, the relay 23 switch closes the contacts 14a and 14b, and the heating current is turned on.Furthermore, the output of the flip-flop 28 becomes high level at the falling edge of the above-mentioned low level, and the terminal C7 becomes low. An interrupt is generated as described above.Therefore, even if the control circuit 19 or the like malfunctions, the timing means ensures that the heating current will not be output after the predetermined time has elapsed, and the hemostasis site will continue to be abnormally heated. It is safe and has no problems.

Note that the means for forcibly cutting off the heating current by the timer means is not limited to the relay 23, and may be formed using a semiconductor such as a iris iris.

Also, the characteristic detection circuit 17 detects the Zener diode 1.
When detecting the characteristics of No. 3 (including short circuits, disconnections, etc.), it is desirable to operate the circuit 17 before and after the actual cauterization and hemostasis treatment. . In this case, it is not necessary to carry out the interrogation during the operation 191, and in the above-mentioned embodiment 1', it is possible to freely change υ1lili during the period in which the phototransistor 15Cp is turned on, but this is not limited to this embodiment. Further, even during use, the characteristic detection circuit 17 can be operated during a period in which heating for cauterization and hemostasis is stopped.

In addition, in the comparison circuit 16 provided in the characteristic detection circuit 17, if a comparator is provided with a level set different from the set level of the comparators 16a and 16b, and the level deviates greatly from the allowable range (that is, short circuit, disconnection, etc.), It is also possible to provide a warning that a failure has occurred in the heating element.

[Effect of the Invention 1] As described above, according to the present invention, a characteristic detection means for detecting characteristic deterioration of the heating element such as short circuit, disconnection, etc. is provided, and the characteristic detection is performed under the same conditions as the manufacturer's product specifications. Therefore, the degree of characteristic deterioration can be detected more reliably. Therefore, the reliability of the cautery hemostasis device can be improved.

[Brief explanation of drawings]

1 to 3 relate to one embodiment of the present invention, in which FIG. 1 is a block diagram showing the main parts of a probe drive circuit in one embodiment, and FIG. 2 is a perspective view showing the appearance of one embodiment. Third
The figure is a circuit diagram showing a specific circuit configuration of a probe drive circuit according to one embodiment. 1... Cauterization hemostasis device 2... Panel 3... Power supply box 5... Heater probe 5A... Connector 7... Foot switch 9... Probe drive circuit 12... Drive constant current circuit 13...Zener diode 14...Switch 15...Minute constant current circuit 16
... Comparison circuit 17 ... Characteristic detection circuit 18 ...
Alarm circuit 19... Control circuit 21... Calorific value detection circuit

Claims (1)

[Claims] By heating a heater probe containing a heating element at the tip,
In a cautery hemostasis device for performing therapeutic procedures such as hemostasis, is the means for supplying a minute constant current to the heating element and whether the voltage across the heating element in a state where the minute constant current is supplied is within an allowable range? 1. A cautery hemostasis device characterized by comprising a characteristic detection means comprising a comparison circuit for determining whether or not the