WO2016093086A1

WO2016093086A1 - Treatment device

Info

Publication number: WO2016093086A1
Application number: PCT/JP2015/083418
Authority: WO
Inventors: 敏文桂木
Original assignee: オリンパス株式会社
Priority date: 2014-12-12
Filing date: 2015-11-27
Publication date: 2016-06-16
Also published as: JPWO2016093086A1

Abstract

This treatment device (1) comprises a heat transfer member (122) that is brought into contact with biological tissue and transfers heat to the biological tissue, and a heating member (128) that heats the heat transfer member. The treatment device (1) also comprises: a drive circuit (230) that supplies, to the heating member, a constant voltage of a first voltage value when ON and a constant voltage of a second voltage value when OFF; an offset value calculation unit (212) that calculates an offset value corresponding to the difference in temperature between the heat transfer member and heating member on the basis of the length of the ON period or the length of the OFF period; an output setting unit (213) that sets the drive circuit (230) to ON or OFF so that the temperature of the heating member is maintained at a revised target temperature obtained by adding the offset value to a target temperature; and a drive control unit (214) that controls operation of the drive circuit on the basis of the ON or OFF setting.

Description

Treatment device

The present invention relates to a treatment apparatus.

Generally, a medical treatment apparatus for grasping a living tissue and heating the living tissue is known. For example, Japanese Patent Application Laid-Open No. 2012-125338 discloses a technique relating to a treatment apparatus that can apply a high-frequency voltage to a grasped living tissue, further heat the tissue, and finally cut the living tissue with a cutter. Is disclosed. In this treatment apparatus, a heating chip that functions as a heater for heating the electrode is provided on the electrode that functions as a heat transfer member that comes into contact with the living tissue. In the temperature control of the heat generating chip, an offset value corresponding to the amount of power supplied to the heat generating chip is calculated in consideration of the temperature difference between the electrode and the heat generating chip. This treatment apparatus maintains the temperature of the heat generating chip at a control target temperature obtained by adding an offset value to the target temperature of the electrode. In this treatment apparatus, it is disclosed that a variable voltage source is mainly used.

Japanese Patent Application Laid-Open No. 2012-024583 also discloses a technique related to an apparatus for heat-treating a living tissue. In this apparatus as well, a variable voltage source is used, and the temperature of the heater is kept constant by adjusting the output voltage.

Generally, the circuit configuration of the constant voltage source is simpler than that of the variable voltage source.

An object of the present invention is to provide a treatment apparatus using a constant voltage source for heating a living tissue, and capable of heating the living tissue to be treated at a predetermined target temperature.

According to one aspect of the present invention, a treatment apparatus is a treatment apparatus for treating a biological tissue by heating it at a predetermined target temperature, wherein the treatment apparatus is in contact with the biological tissue and transfers heat to the biological tissue. A member, a heat generating member disposed on the heat transfer member to heat the heat transfer member, and generating heat when power is supplied thereto; A drive circuit that supplies a voltage and does not supply a constant voltage of the first voltage value to the heat generating member when it is off, and a length of an on period that is a period in which the past drive circuit is on or An offset value calculation unit that calculates an offset value according to a temperature difference between the heat transfer member and the heat generation member based on a length of an off period that is a period during which the drive circuit is off; and To the corrected target temperature with the offset value added An output setting unit that sets the on or off of the drive circuit to maintain the temperature of the thermal member, and controls the operation of the drive circuit based on the on or off set by the output setting unit A drive control unit. *

Moreover, according to one aspect of the present invention, the treatment device is a treatment device for heating and treating a living tissue at a predetermined target temperature, and contacts the living tissue and transfers heat to the living tissue. A heat transfer member, a heat generating member disposed on the heat transfer member so as to heat the heat transfer member, and generating heat when supplied with electric power; A drive circuit that supplies a constant voltage and does not supply a constant voltage having a first voltage value to the heat generating member during the off period, and the heat transfer member and the heat generating element based on a temperature drop of the heat generating member during the off period. An offset value calculation unit that calculates an offset value according to a temperature difference with the member, and a length of the on period in the future so as to maintain the heating member at a corrected target temperature obtained by adding the offset value to the target temperature. Or the length of the off-period And an output setting section for constant, based on the length of the length or the OFF period of the ON period of the output setting unit has set, a drive control unit for controlling the drive circuit.

According to the present invention, it is possible to provide a treatment apparatus that can heat a biological tissue to be treated at a predetermined target temperature in a treatment apparatus that uses a constant voltage source for heat treatment of the biological tissue.

FIG. 1 is a diagram illustrating an outline of an example of an appearance of a treatment apparatus according to the first embodiment. FIG. 2 is a diagram schematically illustrating a configuration example of the treatment apparatus according to the first embodiment. FIG. 3 is a diagram illustrating an outline of a configuration example of the heat transfer member and the heater of the treatment apparatus according to the first embodiment. FIG. 4 is a diagram for explaining heat transfer between the heat transfer member and the heater. FIG. 5 is a flowchart illustrating an example of processing according to the first embodiment. FIG. 6 is a diagram for explaining the operation of the treatment apparatus according to the first embodiment. FIG. 7 is a flowchart illustrating an example of processing according to the second embodiment. FIG. 8 is a diagram for explaining the operation of the treatment apparatus according to the second embodiment. FIG. 9 is a diagram for explaining the operation of the treatment apparatus according to the third embodiment.

[First Embodiment]
A first embodiment of the present invention will be described with reference to the drawings. A schematic view of the appearance of a medical treatment apparatus 1 according to this embodiment is shown in FIG. The treatment device 1 is a device for use in the treatment of living tissue, and is used for, for example, treatments for cutting, incising, sealing, or anastomosing blood vessels or intestinal tracts. The treatment apparatus 1 performs treatment by applying thermal energy to living tissue. As shown in FIG. 1, the treatment device 1 includes a treatment tool 100 and a control device 200.

The treatment tool 100 is a linear type surgical treatment tool for performing treatment by, for example, penetrating the abdominal wall. The treatment instrument 100 includes a handle 160, a shaft 150 attached to the handle 160, and a grip 110 provided at the tip of the shaft 150. The grasping unit 110 can be opened and closed, and is a treatment unit that grasps a living tissue to be treated and performs a treatment such as coagulation or incision of the living tissue. Hereinafter, for the sake of explanation, the grip 110 side is referred to as the distal end side, and the handle 160 side is referred to as the proximal end side. The handle 160 includes a plurality of operation knobs 164 for operating the grip portion 110.

In addition, the shape of the treatment tool 100 shown here is only an example, and other shapes may be used as long as they have the same function. For example, the shaft may be curved. Further, the technology according to the present embodiment is not limited to the treatment apparatus used in the rigid endoscope operation as shown in FIG. 1 but is also applied to the treatment apparatus used in the endoscopic operation using the flexible endoscope. obtain.

The treatment instrument 100 is connected to the control device 200 via a cable 190. Here, the cable 190 and the control device 200 are connected by a connector 195, and this connection is detachable. That is, the treatment apparatus 1 is configured so that the treatment tool 100 can be replaced for each treatment.

A foot switch 290 is connected to the control device 200. The foot switch 290 operated with a foot may be replaced with a switch operated with a hand, for example, a hand switch or another switch. When the operator operates the pedal of the foot switch 290, the supply of energy from the control device 200 to the treatment instrument 100 is switched on / off.

The configuration example of the treatment apparatus 1 will be further described with reference to the schematic diagram shown in FIG. The grasping part 110 of the treatment instrument 100 includes a first grasping member 112 and a second grasping member 114. When the first holding member 112 is displaced with respect to the second holding member 114, the holding unit 110 is opened and closed. The grasping unit 110 is configured to grasp a biological tissue that is a treatment target between the first grasping member 112 and the second grasping member 114.

The first gripping member 112 and the second gripping member 114 have the same configuration. That is, each of the first holding member 112 and the second holding member 114 has a heat transfer member 122. The heat transfer member 122 is made of a metal having high thermal conductivity such as copper. The heat transfer member 122 of the first holding member 112 and the heat transfer member 122 of the second holding member 114 are provided so as to face each other. That is, each heat transfer member 122 is provided so as to contact the living tissue.

Each of the heat transfer members 122 is provided with a heater 124. The heater 124 has a structure in which a heat generating member 128 is provided on a substrate 126. The substrate 126 is, for example, a polyimide substrate. The heating member 128 is, for example, a stainless (SUS) resistance pattern formed on the substrate 126. The heater 124 is disposed so that the substrate 126 is in contact with the heat generating member 128. When power is supplied to the heat generating member 128, the heat generating member 128 generates heat. Heat generated by the heat generating member 128 is transmitted to the heat transfer member 122 via the substrate 126. This heat is transmitted to the living tissue in contact with the heat transfer member 122, and the living tissue is heated.

2, the control device 200 includes a control unit 210, a storage unit 220, a drive circuit 230, an input unit 240, and a display unit 250. In the present embodiment, the control device 200 controls the heating operation of the treatment instrument 100 using a pulse width modulation (PWM) method.

The control unit 210 plays a central role in the control device 200. The control unit 210 is connected to each unit of the control device 200. The storage unit 220 stores various information used for the processing of the control unit 210. The storage unit 220 stores a program for processing performed by the control unit 210.

The drive circuit 230 is a drive circuit for driving the heater 124. The drive circuit 230 and the heater 124 are connected by a conducting wire 132. The drive circuit 230 applies a voltage across the heat generating member 128 of the heater 124. Since PWM control is employed, the drive circuit 230 is configured to output a constant voltage. The drive circuit 230 may not have a variable voltage value.

The input unit 240 is a part that receives user instructions. The input unit 240 includes any one of general input devices such as a button switch, a slider, a dial, a keyboard, and a touch panel. The display unit 250 is a part that displays various types of information related to the control device 200. The display unit 250 includes any one of general display devices such as a liquid crystal display and a display panel using LEDs.

The control unit 210 includes a temperature calculation unit 211, an offset value calculation unit 212, an output setting unit 213, and a drive control unit 214.

The temperature calculation unit 211 calculates the temperature of the heat generating member 128. The electrical resistance value of the heat generating member 128 changes according to the temperature. Therefore, the temperature calculation unit 211 calculates the temperature of the heat generating member 128 based on the electrical resistance value of the heat generating member 128. For this reason, the temperature calculation unit 211 calculates the resistance value of the heat generating member 128 based on the voltage applied to the heat generating member 128 and the current flowing through the heat generating member 128. The storage unit 220 records the relationship between the resistance value and the temperature of the heat generating member 128, and the temperature calculating unit 211 refers to this relationship to acquire the temperature of the heat generating member 128.

The offset value calculation unit 212 calculates the offset value ΔT based on the past output from the drive circuit 230. The offset value ΔT is a value corresponding to the temperature difference between the heat transfer member 122 and the heat generating member 128. The offset value calculation unit 212 determines the offset value based on the length of the on period that is a period during which the driving circuit 230 is on and / or the length of the off period that is a period during which the driving circuit 230 is off. ΔT is calculated.

The output setting unit 213 sets the operation of the drive circuit 230 to maintain the temperature of the heat generating member 128 at the corrected target temperature obtained by adding the offset value ΔT to the target temperature of the heat transfer member 122. The drive control unit 214 controls the operation of the drive circuit 230 based on the setting of the output setting unit 213.

The control unit 210 includes a central processing unit (CPU) or an application specific integrated circuit (ASIC) and performs various calculations. An ASIC or the like may be formed for each element included in the control unit 210 such as the temperature calculation unit 211 or the like.

The heat transfer member 122 and the heater 124 will be further described with reference to FIG. As shown in FIG. 3, the substrate 126 of the heater 124 is slightly smaller than the heat transfer member 122 and has the same shape as the heat transfer member 122. The heat generating member 128 formed on the substrate 126 has both ends provided on the base end side, and has a generally U-shaped pattern. This pattern is formed in a wave shape so as to cover a wide area of the substrate while reducing the line width in order to increase the electrical resistance value. One end of a conducting wire 132 is connected to each end of the heat generating member 128. The other end of the conducting wire 132 is electrically connected to the drive circuit 230.

The heat conduction between the heat transfer member 122 and the heater 124 will be described with reference to FIG. In FIG. 4, the left side shows the positional relationship among the heat transfer member 122, the substrate 126, and the heat generating member 128. Also, the right side of FIG. 4 shows the relationship between position and temperature. In FIG. 4, the upper side shows a case where the temperature of the heat generating member 128 is low, and the lower side shows a case where the temperature of the heat generating member 128 is high. The width of the arrow on the left side of FIG. 4 schematically shows the amount of heat that moves.

As shown in FIG. 4, the greater the amount of heat generated by the heat generating member 128, the greater the amount of heat that moves from the heat generating member 128 to the heat transfer member 122. The greater the amount of heat that moves, the greater the temperature difference between the heat generating member 128 and the heat transfer member 122. That is, as the amount of heat applied to the heat transfer member 122 is larger, the temperature of the heat generating member 128 needs to be set higher than the temperature of the heat transfer member 122.

Next, the operation of the treatment apparatus 1 according to this embodiment will be described. The surgeon first operates the input unit 240 of the control device 200 to set the output conditions of the treatment device 1 such as the target temperature and heating time related to the treatment. As the output condition, the value of each parameter may be set individually, or a set of setting values according to the technique may be selected.

The grasping part 110 and the shaft 150 of the treatment tool 100 are inserted into the abdominal cavity through the abdominal wall, for example. The surgeon operates the operation knob 164 to open and close the grasping unit 110 and grasps the living tissue to be treated by the first grasping member 112 and the second grasping member 114. At this time, the living tissue to be treated comes into contact with the heat transfer member 122 provided on the first holding member 112 and the second holding member 114.

The surgeon operates the foot switch 290 after grasping the living tissue to be treated by the grasping unit 110. When the foot switch 290 is turned on, electric power is supplied from the control device 200 to the heater 124 via the conductive wire 132 passing through the cable 190. Here, the target temperature is 200 ° C., for example. At this time, the current flows through the heat generating member 128. The heat generating member 128 generates heat by this current. The heat generated by the heat generating member 128 is transferred to the heat transfer member 122 through the substrate 126. As a result, the temperature of the heat transfer member 122 rises.

The living tissue in contact with the heat transfer member 122 is cauterized and solidified by the heat transferred to the heat transfer member 122. When the living tissue is solidified by heating, the supply of power to the heater 124 is stopped. The treatment of the living tissue is thus completed.

Control by the control unit 210 will be described with reference to the flowchart shown in FIG. The control of the control unit 210 starts, for example, when the power of the control device 200 is turned on.

In step S101, the control unit 210 sets treatment conditions such as a target temperature and a treatment time based on an input to the input unit 240 by the user. In the following description, the target temperature of the biological tissue to be treated is assumed to be T_target1.

In step S102, the control unit 210 determines whether an instruction to start heating is input. An instruction to start heating is input, for example, when the foot switch 290 is stepped on. When the instruction to start heating is not input, the process returns to step S102. That is, the control unit 210 stands by until an instruction to start heating is input. When an instruction to start heating is input, the process proceeds to step S103.

In step S103, the control unit 210 sets the pulse width W of the pulse output from the drive circuit 230 in the control by the PWM method to an initial value. The initial value of the pulse width W is, for example, half the output period. The initial value of the pulse width W is not limited to this, and may be any value. In step S104, the controller 210 causes the drive circuit 230 to output the pulse having the pulse width W set in step S103. As a result, a current flows through the heat generating member 128 and the heat generating member 128 generates heat. The output voltage of the drive circuit 230 is a predetermined value.

In step S105, the controller 210 calculates the temperature of the heat generating member. More specifically, the controller 210 calculates the resistance value of the heat generating member 128 based on the current that flows during pulse output and a predetermined output voltage value. The controller 210 calculates the temperature of the heat generating member 128 based on the resistance value of the heat generating member 128. Here, the temperature of the heat generating member 128 is derived, for example, by referring to a table including the relationship between the resistance value and the temperature of the heat generating member 128 stored in the storage unit 220. The temperature may be calculated using an expression representing the relationship between the resistance value of the heat generating member 128 and the temperature instead of the table.

In step S106, the control unit 210 calculates the target temperature offset value ΔT based on the pulse width W of the pulse output immediately before, that is, the value related to the duty ratio. Here, the offset value ΔT is, for example,
ΔT = C1 × W + C2 (1)
Is calculated based on Here, C1 and C2 are predetermined constants. The offset value ΔT is not limited to the above equation (1), and may be calculated using, for example, a quadratic equation, a high-order equation, or other equations.

In step S107, the control unit 210 sets a value obtained by adding ΔT to the target temperature as the corrected target temperature. That is, when the target value of the temperature of the living tissue to be treated is T_target1, and the corrected target temperature is T_target2,
T_target2 = T_target1 + ΔT (2)
It becomes. The controller 210 determines the pulse width W of the next pulse to be output so that the temperature of the heat generating member 128 becomes the corrected target temperature T_target2. The pulse width W is, for example, when the pulse width of the previous output is W_1 and the current temperature of the heating member 128 is T_heater,
W = W_1 + (T_target2-T_heater) × C3 / W_1 (3)
Is calculated based on Here, C3 is a predetermined constant. When W calculated using Expression (3) is larger than the maximum pulse width W_max determined based on the period of the output pulse, the pulse width W is set to the maximum pulse width W_max. Note that the maximum pulse width is, for example, about several hundred milliseconds.

In step S108, the control unit 210 causes the drive circuit 230 to output the pulse having the pulse width W determined in step S108.

In step S109, the control unit 210 determines whether or not the treatment is completed. The condition for completing the treatment can be set to any one of the following or others, for example. For example, the treatment may be completed when the output time passes a preset treatment time. Further, for example, the treatment may be completed when the temperature of the living tissue, that is, the temperature of the heat transfer member 122 reaches a predetermined temperature and becomes stable. Further, for example, the treatment may be completed when a predetermined time elapses after the temperature of the living tissue reaches a predetermined temperature.

In step S109, when the treatment is not completed, the process returns to step S105. On the other hand, when the treatment is completed, the process proceeds to step S110. In step S110, the control unit 210 causes the drive circuit 230 to stop outputting. Thereafter, the process ends.

The operation of the treatment apparatus 1 will be described with reference to FIG. In each of the diagrams shown in FIG. 6, the elapsed time is shown on the horizontal axis. In FIG. 6, the intervals between the plurality of broken lines extending vertically represent the period of the output pulse.

The first graph from the top in FIG. 6 shows the pulse output with respect to the elapsed time. That is, this figure switches between an ON state in which a voltage is applied to the heating member 128 in one cycle and an OFF state in which no voltage is applied to the heating member 128, that is, the voltage value is zero. It is shown that. In this figure, the shaded portion indicates that the pulse width W is increased as a result of considering the offset value ΔT. Therefore, if the control is performed so that the temperature of the heat generating member 128 becomes the target temperature T_target1 without using the corrected target temperature T_target2 in consideration of the offset value ΔT, the pulse width W is shortened by the shaded area. Become.

The second graph from the top in FIG. 6 shows the offset value ΔT with respect to the elapsed time. The offset value ΔT depends on the pulse width W of the pulse output immediately before.

The third graph from the top in FIG. 6 shows the temperature of the living tissue with respect to the elapsed time, that is, the temperature of the heat transfer member 122 by a solid line. In this figure, the broken line extending horizontally indicates the target temperature T_target1. In this figure, the alternate long and short dash line indicates the temperature of the living tissue when control is performed so that the temperature of the heat generating member 128 becomes the target temperature T_target1 without using the corrected target temperature T_target2 in consideration of the offset value ΔT. Indicates. Thus, if the offset value ΔT is not considered, the temperature of the living tissue is lower than the target temperature T_target1.

The fourth graph from the top in FIG. 6 shows the temperature of the heat generating member 128 with respect to the elapsed time by a solid line. In this figure, the broken line extending horizontally indicates the target temperature T_target1. In this figure, the alternate long and short dash line of the heat generating member 128 when the control is performed so that the temperature of the heat generating member 128 becomes the target temperature T_target1 without using the corrected target temperature T_target2 in consideration of the offset value ΔT. Indicates temperature. Thus, if the offset value ΔT is not taken into consideration, the temperature of the heat generating member 128 is controlled to be the target temperature T_target1.

According to the treatment apparatus 1 according to the present embodiment, the offset value ΔT is taken into consideration, so that the temperature of the living tissue that is the treatment target is appropriately controlled to be the target temperature T_target1. In this embodiment, since PWM control is used, the output voltage is constant. For this reason, the circuit configuration of the drive circuit 230, which is an output circuit, is simpler than when the output voltage is variable.

In the above-described embodiment, the expression using the pulse width W is shown. However, the expression can be similarly expressed even when using a duty ratio or a period in which the output is off. In the above-described embodiment, the offset value ΔT is determined based on the pulse width W, the duty ratio, etc. of each cycle. However, the present invention is not limited to this, and the offset value ΔT may be determined based on outputs of a plurality of past cycles such as a sum of pulse widths for a plurality of cycles and an average duty ratio.

In the above-described embodiment, the temperature of the heat generating member 128 is acquired based on the electric resistance value of the heat generating member 128. However, the present invention is not limited to this, and the temperature of the heat generating member 128 may be acquired by other methods. For example, a temperature sensor may be provided on the heat generating member 128. However, since the temperature of the heat generating member 128 is acquired based on the electric resistance value of the heat generating member 128, it is not necessary to provide other elements such as a temperature sensor, and the structure of the grip portion 110 is simplified and downsized. The

In the above-described embodiment, the case where both the first gripping member 112 and the second gripping member 114 include the heat transfer member 122 and the heater 124 is shown, but the present invention is not limited thereto. That is, the heat transfer member 122 and the heater 124 may be provided on only one of the first gripping member 112 and the second gripping member 114.

[Second Embodiment]
A second embodiment will be described. Here, differences from the first embodiment will be described, and the same portions will be denoted by the same reference numerals and description thereof will be omitted. In the first embodiment, control using PWM is performed. On the other hand, in this embodiment, on / off control is performed in which the output is turned on when the current temperature is lower than the target temperature, and the output is turned off when the current temperature is higher than the target temperature. Here, the output voltage is constant at a predetermined value. In the present embodiment, the offset value ΔT is determined according to the period during which the output is on within a predetermined period. This is because the heat flux from the heat generating member 128 to the heat transfer member 122 increases as the period during which the output is on within the predetermined period, and the temperature difference between the heat generating member 128 and the heat transfer member 122 increases. Because.

Control by the control unit 210 according to the present embodiment will be described with reference to a flowchart shown in FIG.

In step S201, the control unit 210 sets treatment conditions such as a target temperature and a treatment time based on an input to the input unit 240 by the user. Let T_target1 be the target temperature of the living tissue to be treated. The initial value of the target temperature T_target3 of the heat generating member 128 is also set to the target temperature T_target1 of the living tissue, for example.

In step S202, the control unit 210 determines whether an instruction to start heating is input. When the instruction to start heating is not input, the process returns to step S202. When an instruction to start heating is input, the process proceeds to step S203. In step S203, the control unit 210 sets the output to ON, and causes the drive circuit 230 to output a predetermined voltage.

In step S204, the control unit 210 calculates the electrical resistance value of the heat generating member 128 based on the voltage value and the current value supplied to the heat generating member 128, and obtains the temperature of the heat generating member 128.

In step S205, the controller 210 determines whether or not the temperature of the heat generating member 128 is lower than the target temperature. When the temperature of the heat generating member 128 is lower than the target temperature, the process proceeds to step S206. In step S206, the control unit 210 sets the output to ON, and causes the drive circuit 230 to output a predetermined voltage. Thereafter, the process proceeds to step S210.

In step S205, when the temperature of the heat generating member 128 is not lower than the target temperature, the process proceeds to step S207. In step S207, the control unit 210 sets the output to OFF and does not cause the drive circuit 230 to output a predetermined voltage.

In step S208, the control unit 210 determines whether or not the period during which the output is off is longer than the predetermined period. When the off period is not longer than the predetermined period, the process returns to step S208. On the other hand, when the off period is longer than the predetermined period, the process proceeds to step S209.

In step S209, the control unit 210 turns on the output. That is, after the output is turned off in step S207, the state where the output is off for a predetermined period is continued, and then the output is turned on. The reason why the output is turned on when the predetermined period has elapsed is that since the resistance value of the heat generating member 128 cannot be calculated unless the output is turned on, the temperature of the heat generating member 128 cannot be acquired. After the process of step S209, the process proceeds to step S210.

In step S210, the control unit 210 sets the offset value ΔT, for example, ΔT = C4 × P_on / P_1 (4) according to the ratio of the period P_on in which the output is on in the most recent predetermined period P_1.
Calculate based on

In step S211, the control unit 210 sets the target temperature T_target3 of the heat generating member 128 to T_target3 = T_target1 + ΔT (5)
Calculate based on

In step S212, the control unit 210 determines whether or not the treatment is completed. When the treatment is not completed, the process returns to step S204. On the other hand, when the treatment is completed, the process proceeds to step S213. In step S213, the control unit 210 causes the drive circuit 230 to stop outputting. Thereafter, the process ends.

FIG. 8 shows a relationship among the output state, the offset value ΔT, the temperature of the living tissue, and the temperature of the heat generating member 128 with respect to the elapsed time in the case of the present embodiment. In the example illustrated in FIG. 8, a period from when the output is turned off to when it is turned on is schematically illustrated as a period of three cycles. Further, in the example shown in FIG. 8, a case where the predetermined period P_1 used for calculating ΔT is set to a period of five cycles is schematically shown. These periods may be any period.

Also by the treatment apparatus 1 according to the present embodiment, the offset value ΔT is taken into consideration, so that the temperature of the living tissue that is the treatment target can be appropriately controlled so as to become the initially set target temperature T_target1. In the on / off control according to the present embodiment, the amount of calculation is small because it is determined whether the output is turned on or off depending on whether the current temperature is lower than the target temperature. Further, since the output voltage is constant in this embodiment, the circuit configuration of the drive circuit 230 that is an output circuit may be simple.

[Modification of Second Embodiment]
A modification of the second embodiment will be described. Here, differences from the second embodiment will be described, and the same portions will be denoted by the same reference numerals and description thereof will be omitted.

In the control according to the second embodiment, the temperature of the heat generating member 128 cannot be acquired when the output is turned off. For this reason, the temperature of the heat generating member 128 may be excessively lowered during the period in which the output is off, or the output may be turned on even though the temperature of the heat generating member 128 is higher than the target temperature.

Therefore, in this modification, when the output is turned off, the power supply to the heat generating member 128 is not completely stopped, but a minute voltage is applied to the heat generating member 128 to always acquire the temperature of the heat generating member 128. Shall. That is, the output from the drive circuit 230 is not on or off, but on or a minute voltage. Here, the minute voltage is a voltage that is so small that the heat generated by the heat generating member 128 can be ignored. Thus, when the voltage value when the drive circuit 230 is on is the first voltage value and the voltage value of the minute voltage is the second voltage value, the second voltage value is greater than the first voltage value. Is also small. By applying a minute voltage to the heat generating member 128, the processing of step S208 and step S209 in the control according to the second embodiment described with reference to FIG. 7 can be deleted.

According to the present modification, the temperature of the heat generating member 128 is always acquired, and the output is turned on or the minute voltage is appropriately switched based on this temperature, so that the stability of the temperature control is improved. Further, since the power supply state to the heat generating member 128 can be always grasped, it can be always monitored whether or not an abnormality has occurred in the grip portion 110. Here, the abnormality of the gripping part 110 includes, for example, breakage of the heater 124.

[Third Embodiment]
A third embodiment will be described. Here, differences from the first embodiment will be described, and the same portions will be denoted by the same reference numerals and description thereof will be omitted. In the third embodiment, PWM control is performed. In the third embodiment, the offset value ΔT is determined according to the rate of temperature decrease during the period when the output is off.

The control flow according to this embodiment is the same as that in the first embodiment described with reference to FIG. However, the processing in step S105 and the processing in step S106 are different from those in the first embodiment. Processing of the control unit 210 according to the present embodiment will be described with reference to a flowchart shown in FIG. FIG. 9 shows the relationship among the output state, the temperature of the heat generating member 128, and the offset value ΔT with respect to the elapsed time in the present embodiment.

In step S101, the control unit 210 performs an initial setting based on an input to the input unit 240 by the user. In step S102, control unit 210 determines whether or not an instruction to start heating has been input. When the instruction to start heating is not input, the process returns to step S102. When an instruction to start heating is input, the process proceeds to step S103.

In step S103, the control unit 210 sets the pulse width W of the pulse output from the drive circuit 230 to an initial value. In step S104, the controller 210 causes the drive circuit 230 to output the pulse having the pulse width W set in step S103.

In step S105, the controller 210 calculates the temperature of the heat generating member. Here, in the present embodiment, the control unit 210 calculates the temperature of the heat generating member 128 immediately after the output is turned on and the temperature of the heat generating member 128 immediately before the output is turned off.

In step S106, the control unit 210 calculates an offset value ΔT. Here, in the present embodiment, the offset value ΔT is the value immediately after the output at the previous output is turned on from the temperature T1 (for example, the temperature T11 in FIG. 9) of the heat generating member 128 immediately before the output at the previous output is turned off. A value corresponding to the temperature drop of the heat generating member 128 to the temperature T2 (for example, the temperature T21 in FIG. 9). For example, the offset value ΔT (for example, the offset value ΔT1 in FIG. 9) is
ΔT = C5 × (T1-T2) / t_off (6)
It is determined based on. Here, C5 is a predetermined constant, and t_off is the length of the off period in the previous output. It can be said that the faster the temperature drop, the easier the heat of the heat generating member 128 is taken away. In such a state, the temperature difference between the temperature of the heat generating member 128 and the temperature of the heat transfer member 122 becomes large. Therefore, in such a case, the offset value ΔT is set large. On the other hand, it can be said that the slower the temperature drop, the more difficult the heat of the heat generating member 128 is taken away. In such a state, the temperature difference between the temperature of the heat generating member 128 and the temperature of the heat transfer member 122 becomes small. Therefore, in such a case, the offset value ΔT is set small.

In step S107, the control unit 210 sets a value obtained by adding ΔT to the target temperature as a corrected target temperature, and determines a pulse width W of a pulse to be output next based on the corrected target temperature. In step S108, the control unit 210 causes the drive circuit 230 to output the pulse having the pulse width W determined in step S108.

In step S109, the control unit 210 determines whether or not the treatment is completed. When the treatment is not completed, the process returns to step S105. On the other hand, when the treatment is completed, the process proceeds to step S110. In step S110, the control unit 210 causes the drive circuit 230 to stop outputting. Thereafter, the process ends.

9 will be described with reference to FIG. 9 showing the relationship between the output state with respect to the elapsed time, the temperature of the heat generating member 128, and the offset value ΔT in this embodiment. In FIG. 9, the first graph from the top shows the output state, and here, for the purpose of explanation, numbers (1) to (6) are assigned to the pulses.

The second graph from the top shows the temperature of the heat generating member 128. Here, for explanation, the temperature immediately before turning off the pulse (1) is T11, the temperature immediately after turning on the pulse (2) is T21, and the temperature immediately before turning off the pulse (2) is T12. The temperature immediately after the pulse (3) is turned on is T22, and similarly, the temperatures are T13, T23, T14, T24, T15, and T25.

The third graph from the top shows the offset value ΔT. Here, ΔT1 is calculated based on the temperature T11 and the temperature T21. Similarly, ΔT2 is calculated based on the temperature T12 and the temperature T22. The same applies hereinafter.

Also by the treatment apparatus 1 according to the present embodiment, the offset value ΔT is taken into consideration, so that the temperature of the living tissue that is the treatment target can be appropriately controlled so as to become the initially set target temperature T_target1.

[Modification of Third Embodiment]
A modification of the third embodiment will be described. Here, differences from the third embodiment will be described, and the same portions will be denoted by the same reference numerals and description thereof will be omitted.

In the control according to the third embodiment, the temperature of the heat generating member 128 is not acquired while the output is off. For this reason, in order to obtain the rate of temperature decrease during the period in which the output is off, the temperature of the heating member 128 immediately before turning off the output in the previous output and immediately after turning on the output in the previous output The temperature of the heating member 128 must be used. Therefore, when the situation changes suddenly, the previous situation may not be accurately grasped.

Therefore, in this modified example, as in the modified example of the second embodiment, when the output is turned off, the power supply to the heat generating member 128 is not completely stopped, but a minute voltage is applied to the heat generating member 128. Thus, the temperature of the heating member 128 is always acquired. That is, the output from the drive circuit 230 is not on or off, but on or a minute voltage. As a result, the output becomes a minute voltage using the temperature of the heating member 128 immediately before the output at the previous output is set to a minute voltage and the temperature of the heating member 128 just before the output at the current output is turned on. The rate of temperature decrease during a certain period can be obtained. Further, the speed may be obtained from the temperature drop during a part of the period when the output is a minute voltage.

According to this modification, the temperature of the heat generating member 128 is always acquired, so that the immediately preceding situation is accurately grasped, and the offset value ΔT is calculated based on the immediately preceding situation. Therefore, a more appropriate offset value ΔT can be calculated. Further, since the power supply state to the heat generating member 128 can be always grasped, it can be always monitored whether or not an abnormality has occurred in the grip portion 110.

In any of the processes described above, the order of the processes can be changed as appropriate. Also, some processes may be deleted or other processes may be inserted.

Claims

A treatment device for heating and treating a living tissue at a predetermined target temperature,
A heat transfer member that contacts the living tissue and transfers heat to the living tissue;
A heating member disposed on the heat transfer member so as to heat the heat transfer member and generating heat when power is supplied;
A constant voltage having a first voltage value is supplied to the heat generating member when it is on, and a constant voltage having a second voltage value smaller than the first voltage value is supplied to the heat generating member when it is off. A drive circuit;
Based on the length of the on period that is the period in which the drive circuit was on in the past or the length of the off period that is the period in which the drive circuit was off, the heat transfer member and the heat generating member An offset value calculation unit for calculating an offset value according to the temperature difference;
An output setting unit that sets the on or off of the drive circuit so as to maintain the temperature of the heat generating member at a corrected target temperature obtained by adding the offset value to the target temperature;
A treatment device comprising: a drive control unit that controls an operation of the drive circuit based on the on or the off set by the output setting unit.
The treatment apparatus according to claim 1, wherein the output setting unit sets the on or off of the drive circuit by a pulse width modulation method.
The output setting unit determines whether or not the temperature of the heat generating member is lower than the corrected target temperature, and sets the drive circuit to ON when the temperature of the heat generating member is lower than the corrected target temperature. The treatment device according to claim 1.
A temperature calculator that calculates the temperature of the heat generating member based on the electrical resistance value of the heat generating member;
The output setting unit determines the length of the on period or the length of the off period based on the temperature of the heat generating member calculated by the temperature calculation unit.
The treatment device according to claim 1.
The treatment apparatus according to claim 1, wherein the second voltage value is zero or a minute voltage value.
A treatment device for heating and treating a living tissue at a predetermined target temperature,
A heat transfer member that contacts the living tissue and transfers heat to the living tissue;
A heating member disposed on the heat transfer member so as to heat the heat transfer member and generating heat when power is supplied;
A drive circuit that supplies a constant voltage having a first voltage value to the heat generating member during an on period and supplies a constant voltage having a second voltage value that is smaller than the first voltage value to the heat generating member during an off period. When,
An offset value calculation unit that calculates an offset value according to a temperature difference between the heat transfer member and the heat generation member based on a temperature decrease of the heat generation member in the off period;
An output setting unit for setting the length of the on period in the future or the length of the off period so as to maintain the temperature of the heat generating member at the corrected target temperature obtained by adding the offset value to the target temperature;
A treatment apparatus comprising: a drive control unit that controls the drive circuit based on the length of the on period or the length of the off period set by the output setting unit.