JPH11332825A - Gas feeding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas feeding apparatus at a lower cost which secures the accuracy at a low flow rate without lowering the maximum flow rate of a gas. SOLUTION: A primary decompression device 92 disposed on the upstream side of an electropneumatic proportional valve 93 for adjusting a feeding flow rate of a gas is so arranged that a high pressure gas supplied from a gas cylinder 54 is adjusted to be reduced down to 4 kgf/cm<2> or 1 kgf/cm<2> , for instance, and supplied to the electropneumatic proportional valve 93. A knob 10 arranged on a front panel is turned and operated to control the primary decompression device 92 through a shaft 11. Thus, the high pressure gas is reduced down to 4 kgf/cm<2> or 1 kgf/cm<2> in pressure to be supplied to the electropneumatic proportional valve 93.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air supply device for supplying an air supply gas such as carbon dioxide gas into a body cavity of a human or an animal.

[0002]

2. Description of the Related Art In recent years, in the medical field, a trocar for guiding an observation endoscope into a body cavity and a trocar for guiding a treatment tool to a treatment site without opening the laparotomy in order to reduce invasion to a patient. Puncture the abdomen etc. through the patient's body surface,
2. Description of the Related Art Laparoscopic surgery for performing a therapeutic treatment while observing a treatment tool and a treatment site with an endoscope is performed. In this technique,
In order to secure the space of view for the endoscope and the procedure,
Endoscope systems such as an insufflation device for injecting an insufflation gas such as carbon dioxide gas into the abdominal cavity and an electrosurgical device also serving as a hemostatic treatment for stopping bleeding after the treatment are used.

In recent years, for example, as procedures performed in laparoscopic surgery have become more complicated, the amount of gas leaked into the abdominal cavity or the like as described above has decreased due to the use of a suction device or frequent replacement of treatment tools. is increasing. In order to cope with this increase in the amount of leak, the flow rate specification required for the air supply device is also increasing, and some devices have a maximum flow rate exceeding 40 L / min. On the other hand, laparoscopic surgery has been widely applied to children. In this operation for children, the flow rate is set to about 1 L / min to minimize the invasion.

As described above, the air supply device needs to adjust the flow rate of the air supply gas.
In the device disclosed in Japanese Patent Application Publication No. 0, the flow rate is adjusted using a flow rate adjusting valve.

[0005]

However, in the conventional air supply device, the maximum flow rate of the air supply gas is set to, for example, 40 L /
In the case where the gas flow rate is set to about min, the full scale is large, and it is very poor in terms of precision to control the gas flow rate to about 1 L / min or the like in this apparatus. For this reason, it is difficult to ensure the necessary flow control accuracy for children, for example, and if the intra-abdominal pressure exceeds the set value or if excessive carbon dioxide gas is supplied into the abdominal cavity, high carbon dioxide May cause blood (Child Nursing 19, Fujimoto et al. 1996). Furthermore, if both the control element for the high flow rate and the control element for the low flow rate are provided, the accuracy of the flow rate in the low range can be improved, but the cost of the apparatus increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an air supply device which is low in cost and can ensure the accuracy of a low flow rate without lowering the maximum gas flow rate. .

[0007]

According to the present invention, there is provided an air supply apparatus for injecting gas into a living body of a human body or an animal, in which the pressure and flow rate of the gas to be supplied are controlled. A control unit, a flow rate setting means for setting a flow rate of the gas to be sent, a pressure adjusting means for adjusting a gas pressure for adjusting a flow rate of the gas to be sent, and a pressure of the gas input to the pressure adjusting means. Preliminary pressure adjusting means for variably adjusting, or resistance adjusting means for variably adjusting the gas flow resistance downstream of the pressure adjusting means, comprising an output pressure of the preliminary pressure adjusting means or a resistance value of the resistance adjusting means, It is characterized in that it can be adjusted according to the set value by the flow rate setting means.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 4 relate to a first embodiment of the present invention, and FIG. 1 shows an apparatus for performing an endoscopic operation using a medical endoscope system and a state of use. Figure,
FIG. 2 is an explanatory diagram showing a specific configuration of the air supply device, FIG. 3 is a perspective view showing the appearance of the air supply device, and FIG. It is a graph.

As shown in FIG. 1, an endoscope system 1 includes, for example, an endoscope 2 having an eyepiece 21 at a base end, a light source device 3 for supplying illumination light to the endoscope 2, and a treatment. A high-frequency ablation device 4 for stopping the bleeding of the site and ablating the tissue, and an air supply device 5 according to the present embodiment for supplying an air supply gas for inflating the abdominal cavity in order to secure a visual field and a treatment area. Is configured.

The abdomen of the patient is pierced with trocars 6 and 7 which are guide tubes having insertion holes for guiding the endoscope 2 and surgical instruments into the abdominal cavity.
One end of an insufflation tube 8 made of vinyl chloride or Teflon is removably attached to the trocar 6 having an insertion hole 6a through which the is inserted. The insertion hole 7 of the trocar 7
For example, a high-frequency treatment tool 41 is inserted through a.

The endoscope 2 and the light source device 3 are connected to a light guide cable 2 extending from a base end side of the endoscope 2.
The illumination light generated by a lamp 31 provided in the light source device 3 is illuminated by a lens 32 so that an end face of the light guide cable 22 can be detachably connected thereto. The light is condensed. The illumination light collected on the end face of the light guide cable 22 is transmitted to the distal end portion 24 of the endoscope 2 through a light guide fiber bundle passing through the light guide cable 22 so as to illuminate the subject. Has become. The illumination light emitted from the distal end is reflected by the subject, forms an image of the subject in the endoscope 2, and the subject image is transmitted to the eyepiece 21 via an observation optical system (not shown). It has become so.

The high-frequency ablation device 4 and the high-frequency treatment tool 41
Is electrically connected to an active electrode 43 provided on the high-frequency ablation device 4 via an active cord 42 extending from the base end side of the high-frequency treatment tool 41.
Further, a patient plate 45 formed in a flexible and sheet-like shape so as to be in close contact with the skin of the human body is connected to the patient electrode 44 of the high-frequency ablation device 4. The active electrode 43 and the patient electrode 44 of the high-frequency ablation device 4 are connected to an HF output amplifier 46 that generates high-frequency power and is provided inside the device.

The other end of the insufflation tube 8 whose one end is detachably connected to the trocar 6 is detachably connected to an air supply base 51 provided in the air supply device 5. I have. Further, the air supply device 5 is provided with a high-pressure base 52, and one end of a high-pressure air supply tube 53 is connected to the high-pressure base 52, and the other end is filled with, for example, liquefied carbon dioxide. Connected to the supplied gas cylinder 54.

The liquid carbon dioxide filled in the gas supply gas cylinder 54 is vaporized and reduced to a predetermined pressure through a valve unit 9 in the apparatus, and then the insufflation tube 8 and the insertion hole of the trocar 6 are inserted. It is fed into the abdominal cavity through 6a. The flow rate of the carbon dioxide gas supplied into the abdominal cavity is controlled by a control unit 55 electrically connected to the valve unit 9. Further, the gas supply gas cylinder 54 is filled with 60 kgf / cm ² gas supply gas at normal temperature. Next, details of the air supply device 5 according to the present embodiment will be described with reference to FIG. As shown in the figure, the air supply device 5 including the valve unit 9 and the control unit 55 has an internal portion that guides an air supply gas supplied from the high-pressure base 52 to the air supply base 51 through the valve unit 9. A conduit 56 is provided. The valve unit 9 measures the pressure of the insufflation gas supplied from the insufflation gas cylinder 54 and allows the operator to recognize the remaining amount of the insufflation gas. The first pressure gauge 91 has a measurement range of, for example, 0 to 100 kgf / cm ² . A primary pressure reducing device 92 serving as a preliminary pressure adjusting means for reducing the pressure of the gas supplied from the gas supply gas cylinder 54 to, for example, 1 or (or) 4 kgf / cm ^2; An electropneumatic proportional valve 93 as a pressure adjusting means for adjusting the air supply flow rate by reducing the pressure reduced by the vessel 92 to a range of 0 to 100 mmHg (0 to 0.13 kgf / cm ² ) with a control voltage of 0 to 24 V, Open / close controllable first valve 94, 0-50L / min
Flow measuring unit 95 having a flow rate sensor 95a for measuring the range of pressure, the first pressure sensor 9 for measuring the range of 0 to 100 mmHg
6a and the second pressure sensor 96b, a second
A valve 97, a heater 98 configured to heat the gas supplied through the second valve 97, for example, a heater and a thermostat, and a gas supply temperature for measuring the temperature of the gas supplied by the heater 98. It is configured by an air supply gas temperature measurement unit 99 having a sensor. In addition, the second
Branch line 56 branched between valve 97 and heater 98
A is provided with an exhaust valve 100 that opens the valve when the pressure of the supplied gas from the second valve 97 to the abdominal cavity exceeds a predetermined value and discharges the supplied gas to the atmosphere.

The primary decompressor 92 converts the high-pressure gas supplied from the gas cylinder 54 to, for example, 4 kgf / cm ² or (or)
The pressure can be adjusted to 1 kgf / cm ² . In the illustrated example, a shaft 11 is provided on a dial-type knob 10 provided on the front panel of the air supply device 5, and this shaft 11 is connected to a primary decompressor 92. The primary decompressor 92 is controlled via the.

Further, on the front surface of the air supply device 5, there are provided a setting section for setting the pressure, flow rate, temperature and peritoneal pressure of the gas supplied to the peritoneal cavity, and a display panel for displaying room temperature, peritoneal pressure value and the like. A setting display section 57 is provided.

The setting display section 57, the first pressure gauge 91, the electropneumatic proportional valve 93, the first valve 94, the flow rate measuring section 95, the first
Pressure sensor 96a, second pressure sensor 96b, second valve 97, heater 98, supply gas temperature measurement unit 99, exhaust valve 1
00 are electrically connected to the control unit 55.

The control unit 55 includes a power connector 5
Power is supplied via the power supply 8. Also,
The first valve 94 and the second valve 97 form an intra-abdominal pressure measuring unit for determining the abdominal pressure. That is, once the first valve 94 and the second valve 9
7 is closed to form a tank portion and filled with pressure, and then the change in pressure in the tank portion when the second valve 97 is opened is determined by the first pressure sensor 96a and the second pressure sensor 96b. The measured value is transmitted to the control unit 55, and the pressure in the abdominal cavity is calculated by a CPU provided in the control unit from the pressure drop characteristic at this time.

The operation (first method of use) of the air supply device 5 configured as described above will be described. After setting the pressure in the abdominal cavity of the patient and the flow rate of the insufflation gas using the setting unit of the setting display unit 57, the insufflation is started by operating a start button (not shown). Then, the first valve 94 and the second valve 97
The gas is supplied into the body cavity and the pressure in the abdominal cavity increases while repeating the state in which the insufflation gas flows / the state in which the insufflation gas flow stops according to the opening / closing control. At this time,
The control unit 55 constantly monitors the value of the pressure difference between the set intra-abdominal pressure value of the patient and the actual intra-abdominal pressure. When the pressure difference between the patient's intraperitoneal pressure value and the actual intraperitoneal pressure is reduced, the controller 55 outputs an electric signal to lower the voltage to the electropneumatic proportional valve 93 to reduce the air supply flow rate, An electric signal for shortening the open state time is output to the second valve 97, and the pressure in the abdominal cavity is adjusted by, for example, adjusting the flow rate of the insufflation gas flowing into the abdominal cavity.

When the controller 55 detects that the pressure in the abdominal cavity has risen to a set pressure, for example, 5 mmHg by the surgeon pressing the abdomen of the patient while the insufflation gas is being fed into the abdominal cavity. Then, a signal for opening the valve is output from the control unit 55 to the exhaust valve 100, and the gas in the abdominal cavity is exhausted from the exhaust valve 100 to the atmosphere to reduce the pressure in the abdominal cavity to the set pressure.

The primary decompressor 92 disposed upstream of the electropneumatic proportional valve 93 is provided with the dial-type knob 10.
Is turned to the position H indicated on the front panel, the high-pressure gas supplied from the gas cylinder 54 is reduced to 4 kgf / cm ² and supplied to the electropneumatic proportional valve 93. On the other hand, the knob 1
When 0 is turned to the L position, the high pressure gas is reduced to 1 kgf / cm ² and supplied to the electropneumatic proportional valve 93.

Next, the characteristics of the electropneumatic proportional valve 93 will be described with reference to FIG. The horizontal axis indicates the current supplied to the electropneumatic proportional valve, and the vertical axis indicates the flow rate output from the electropneumatic proportional valve. A curve H is a characteristic when the pressure reduction value of the primary pressure reducer 92 is 4 kgf / cm ² (a characteristic when the input pressure to the electropneumatic proportional valve 93 is high), and a curve L is
This is the characteristic in the case of 1 kgf / cm ² (the characteristic in the case where the input pressure to the electropneumatic proportional valve 93 is low). When the current value applied to the electropneumatic proportional valve 93 is gradually increased from 0 mA, there is a dead zone where pressure is not output from the electropneumatic proportional valve 93 as shown in the figure.
This is due to the characteristics of the opening and closing operation of the valve inside the electropneumatic proportional valve 93. The valve inside the electropneumatic proportional valve 93 is urged in the closing direction by the gas input from the primary pressure reducer 92. On the other hand, the valve is urged in the opening direction by the electromagnetic force generated by the input current. Therefore, unless current is input until the gas pressure is overcome, the valve does not open, which is a dead zone. In the case of curve H, the input gas pressure is equal to curve L
Because it is larger than the case, the dead zone is also large.

Further, as shown by the portion A in FIG. 4, the flow rate increase rate of the curve H is larger than that of the curve L. The reason will be described. The flow rate value depends on (1) the opening degree of the valve inside the electropneumatic proportional valve 93 and (2) the magnitude of the gas pressure input to the electropneumatic proportional valve 93. Since the opening degree of the internal valve of the electropneumatic proportional valve 93 substantially matches the input current, the curves H and L are almost the same. However, the gas pressure input to the electropneumatic proportional valve 93 is, as described above, the curve H
Is larger. Therefore, at the same input current value, the flow rate increase rate is higher in the case of the curve H.

In the characteristic shown in FIG. 4, when the calculation is performed including the dead zone, the average flow rate increase rate is as follows. Curve H
= 227 L / min / A, curve L = 36 L / min /
A. On the other hand, the accuracy of the output current is 1% of 0.3A.
Then, it becomes ± 0.003A. When this accuracy is multiplied by the flow rate increase rate of each curve, a control error of the flow rate is obtained, and the curve H = ± 0.7 L / min and the curve L = ± 0.1 L
/ Min.

As described above, the curve L has a smaller dead zone and a smaller flow rate increase rate. Therefore, the control accuracy of the output flow rate in the low flow rate range can be increased.

Using the output characteristics of the electropneumatic proportional valve 93, the apparatus is set for each operation as follows. In a normal laparoscopic operation requiring a large flow rate, the knob 10 is turned to the position H, and the output flow characteristic is set to a curve H. In a normal laparoscopic operation, a high flow rate region is required, and a low flow rate region is not used or accuracy is not required. Therefore, the curve H is suitable. On the other hand, in laparoscopic surgery on a child, the knob 10 is turned to the position of L, and the flow characteristic is set to a curve L. In the case of the curve L, since the control accuracy of the output flow rate is high, high-precision control is possible even in a low flow rate range.

In the present embodiment, since the pressure of the gas input to the electropneumatic proportional valve 93 can be adjusted, the control accuracy in the low flow rate range can be increased without reducing the maximum flow rate value as the air supply device. Can increase the safety of surgery for children. Also, the adjustment knob 1 of the primary decompressor 92
0 is simply installed on the front panel of the air supply device 5, so that the cost can be reduced.

Next, a second method of using the air supply device of the first embodiment will be described.

FIG. 5 is a graph showing the second method of use, showing the input current-output pressure characteristics of the electropneumatic proportional valve 93.
The horizontal axis indicates the current supplied to the electropneumatic proportional valve, and the vertical axis indicates the output gas pressure of the electropneumatic proportional valve.

Generally, the output characteristics of the electropneumatic proportional valve vary from device to device due to individual differences. The electropneumatic proportional valves A, B, and C shown in FIG. 5 show variations in output characteristics of the three electropneumatic proportional valves. If individual differences occur in the electropneumatic proportional valve in this way, the flow characteristics will also vary, and errors will increase, making it difficult to secure the required air supply accuracy, especially in pediatric surgery.

Therefore, this can be solved by adopting the second usage method. First, when a power switch (not shown) is turned on, an output pressure measurement mode of the electropneumatic proportional valve 93 is entered. First, it is confirmed by the first pressure gauge 91 that the pressure of the gas cylinder 54 is 50 kgf / cm ² or more. Next, with the second valve 97 closed, the first valve 94
open. Thereafter, the current value input to the electropneumatic proportional valve 93 is increased by a fixed ratio, for example, 0.01 A. Then, the output pressure of the electropneumatic proportional valve 93 at each value is determined by the first pressure sensor 96a.
Measure with The measured value is input to the control unit 55 and stored. In this way, for example, the control unit 55 stores 30 values. Next, when a start switch (not shown) is pressed, the output pressure of the electropneumatic proportional valve 93 corresponding to the set flow rate value is calculated by the control valve 55, and then a current is input to the electropneumatic proportional valve 93. At this time, a necessary input current is determined and output from the 30 input current-output pressure characteristics stored in the control unit 55.

In this manner, the individual difference of the electropneumatic proportional valve 93 is corrected, and accurate gas flow control can be performed.

Next, a third method of using the air supply device of the first embodiment will be described.

Conventionally, in laparoscopic surgery for adults, a trocar having a diameter of about φ5 to 12 is punctured into the abdomen of a patient, and the trocar is operated through an endoscope or a treatment tool. However, in pediatric surgery, trocars having a diameter of about 2 to 3 have been punctured and used in order to make the invasion smaller. The gap between the φ2 to 3 trocar and the endoscope is very small, and has a very large resistance to the flow of the gas to be supplied. For this reason, in the conventional air supply device, it may be determined that a part of the conduit leading to the patient is clogged, a warning is issued, or accurate pressure measurement may not be performed. In such a case, a trocar having a diameter of about 5 to 12 which has been conventionally used has to be used in some cases, and the invasion of the operation to the patient has been increased.

The third method of use enables accurate gas control even when a trocar of φ2 to φ3 is used.

The third method of use will be described with reference to FIGS. First, an operation when a conventional trocar of φ5 to 12 is used will be described. When gas is supplied to the patient, the first valve 94 and the second valve 97 are supplied at t1.
Open at the same time. Then, the gas whose pressure has been adjusted by the electropneumatic proportional valve 93 flows toward the patient. At this time, the pressure inside the pipeline 56 increases (the air supply section in FIG. 6). After a certain period of time, for example, when the first valve 94 is closed at the time t2 after the air supply for 2 seconds, the gas remaining in the conduit 56 ends flowing to the abdominal cavity of the patient, in other words, the gas in the conduit 56 At time t3 when the pressure of the patient becomes equal to the pressure of the abdominal cavity of the patient, the control unit 55 reads the measured values of the pressure sensors 96a and 96b. The subsequent control is performed based on the read value.

Next, the case where a trocar of φ2-3 is used will be described. In this case, the characteristics after the first valve is closed at time t2 are different from those when a trocar of φ5 to 12 is used. The characteristic from time t2 is shown by the dotted line in FIG. The gas in the conduit 56 is difficult to escape into the abdominal cavity of the patient due to the large conduit resistance, and the abdominal cavity of the patient and the pressure sensors 96a, 96b
It is at time t4 that the pressures in the sections become equal. At this time, the control unit 55 calculates the pressure drop characteristics. This is the portion indicated by Δp / Δt in FIG. When this value becomes smaller than a certain threshold value, for example, 50 mmHg / s, it is determined that a trocar with a large pipeline resistance value is connected, and
Switch to a mode that extends the maximum waiting time from t2 until pressure measurement. In addition, the timing for starting the warning is also delayed.

As described above, in the third method of use,
Even when a device having a large resistance is used, accurate pressure measurement is possible. In addition, malfunction of the warning can be prevented.

As another form of the present usage method, Δp
When it is determined that the trocars of φ2 to φ3 are connected by measuring / Δt, the output value of the electropneumatic proportional valve 93 is set to a value equal to the set value of the abdominal cavity pressure of the patient. For example, the output value of the electropneumatic proportional valve 93 usually drops from 50 to 100 mmHg to 10 mmHg, which is the set value of the abdominal pressure of the patient. If the pressure in the abdominal cavity of the patient has reached 10 mmHg, no more gas flows since it becomes equal to the output pressure of the electropneumatic proportional valve 93. As described above, accurate control is performed without measuring the abdominal cavity pressure.

The operation as shown in FIG. 7 can be performed to improve the problem that the time from time t2 to time t4 is too long. That is, after closing the first valve 94 at the time t2, Δp / Δt is measured, and when it is determined that the trocar of φ2 to φ3 is connected, the gas in the pipeline is released by the exhaust valve 100 ( tR). By this operation, the pressure in the duct becomes equal to the pressure in the abdominal cavity of the patient, so that the waiting time until the pressure measurement can be reduced.
As a result, it is possible to immediately move to the next cycle of the insufflation operation, to reduce the time required for the patient's abdominal cavity to reach the set value, and to smooth the operation flow.

When the trocar having a small diameter is used as described above, since the flow rate is reduced, the insufflation tube 8 shown in FIG. 2 is branched and connected to two ports to compensate for the decrease. It may be.

Next, a second embodiment of the present invention will be described with reference to FIG.

FIG. 8 is an explanatory diagram showing the configuration of the air supply device.

In the second embodiment, an electropneumatic proportional valve 92 is used instead of the primary pressure reducer 92 described in the first embodiment.
There is a characteristic in that a is provided. Therefore, only the parts different from the first embodiment will be described. A second electropneumatic proportional valve 92a is provided downstream of the first pressure gauge 1, and an electropneumatic proportional valve 93 is connected downstream of the second electropneumatic proportional valve 92a. The second electropneumatic proportional valve 92a is electrically connected to the control unit 55 similarly to the electropneumatic proportional valve 93.

In this configuration, the second electropneumatic proportional valve 92
The current value input to a increases in proportion to the flow value set by the operator. That is, if the set flow rate value is small,
The output pressure of the second electropneumatic proportional valve 92a is small. Conversely, if the set flow value is large, the second electropneumatic proportional valve 92
The output pressure of “a” increases. As a result, the electropneumatic proportional valve 93
The operation of the curve H shown in FIG.
And becomes the same as the curve L when the installation value is maximized. Further, the characteristic of the electropneumatic proportional valve 93 when the flow rate set value is set between the maximum value and the minimum value is represented by a curve M intermediate between the curves H and L.

As described above, in the second embodiment,
Since the output characteristics of the electropneumatic proportional valve 93 can be automatically changed according to the flow rate set value set by the operator, the operation is simplified. Further, in this embodiment, since it is not necessary to operate the knob 10 of the front panel as in the first embodiment, the safety is improved without fear of forgetting to operate.

Next, a third embodiment of the present invention will be described with reference to FIGS.

FIG. 9 is an explanatory view showing the structure of the air supply device, and FIG.
0 is a graph showing the relationship between the supply current of the electropneumatic proportional valve and the flow rate of the supplied gas.

In this embodiment, a variable throttle 1 as an electrically controllable resistance adjusting means is provided downstream of the electropneumatic proportional valve 93.
The throttle valve 12 is electrically connected to the control unit 55 and is controlled by the control unit 55.

Although the electropneumatic proportional valve 93 has a dead zone in the low range as described above, the throttle 12 is provided downstream of the electropneumatic proportional valve 93 as shown in FIG. 9 to increase the flow resistance. As a result, the maximum flow rate value is reduced, but the flow rate resolution per unit supply current is improved, and the dead zone is reduced as shown in FIG. FIG. 10 shows the output characteristics of the electropneumatic proportional valve 93. When the flow rate set value is maximized, the throttle amount of the throttle 12 becomes the minimum value and the flow rate increase rate becomes the maximum. On the other hand, when the throttle value of the throttle 12 is set to the maximum value, the flow rate increase rate becomes minimum.

The third embodiment is different from the first and second embodiments.
Compared with the embodiment, although the dead zone is not improved, the flow rate accuracy in the low flow rate region can be improved by increasing the aperture value, and the air supply control accuracy can be improved.

As another configuration of the present embodiment,
Even if an aperture is not provided in the apparatus, the same operation and effect can be obtained by attaching an adapter (not shown) for reducing the pipe diameter to the base 51. This adapter is used when used at a low flow rate. In this case, the outer diameter of the tube mounting portion of the adapter can be made small, and the diameter of the tube 8 can be reduced. By reducing the diameter of the tube 8 in this manner, the long tube 8 becomes lightweight and easy to handle.

Next, a fourth embodiment of the present invention will be described with reference to FIG.

In this embodiment, a plurality of conduits 13a, 13b having different resistance values are provided in place of the variable throttle 12 provided in the second embodiment, and these conduits 13a, 13b are provided.
13b is switched. FIG.
In 1, 14 is a throttle, 15 is a solenoid valve disposed in the pipeline, one 15a is, for example, MAX40L / min, and the other 15b is
MAX10L / min. In the fourth embodiment, the same function can be realized at lower cost than when a variable aperture is used.

[Supplementary Notes] (1) In an air supply device for injecting gas into a living body of a human body or an animal, a control unit for controlling the pressure and flow rate of the gas to be sent, and a flow rate for setting the flow rate of the gas to be sent Setting means, pressure adjusting means for adjusting the gas pressure for adjusting the flow rate of the gas to be sent, preliminary pressure adjusting means for variably adjusting the pressure of the gas input to the pressure adjusting means, or the pressure adjusting means. Resistance adjusting means for variably adjusting the flow resistance of the downstream gas, wherein the output pressure of the preliminary pressure adjusting means or the resistance value of the resistance adjusting means can be adjusted according to the set value by the flow rate setting means. A characteristic air supply device.

In this supplementary item, the output pressure of the preliminary pressure adjusting means is adjusted according to the flow rate set value.

(2) In the apparatus described in the above item (1), the output pressure of the pressure adjusting means can be changed and adjusted by an electric signal, and the control unit controls the pressure in accordance with a set value by the flow rate setting means. The air supply device according to the above item 1, wherein the electric signal sent to the adjusting device is controlled. In this additional item, the output pressure of the pressure adjusting device is controlled by an electric signal.

(3) By manually operating the adjustment knob,
The air supply device according to the above item 1, wherein the output pressure of the preliminary adjusting device is adjusted. In this additional item, the output pressure of the preliminary pressure adjusting device is manually adjusted.

(4) The output pressure of the pre-adjustment means can be changed by an electric signal, and the control unit controls an electric signal to be sent to the pre-adjustment means in accordance with a value set by the flow rate setting means. In this additional item, the output pressure of the preliminary pressure adjusting means is adjusted by an electric signal.

(5) Input electric signal of the pressure adjusting means
The air supply device according to claim 1, wherein the output characteristic can be stored by the control unit. In this additional item, the input current-output characteristic of the pressure adjusting unit is stored in the control unit.

(6) In a device for injecting gas into a living body of a human or animal body, a flow rate setting means for setting a gas flow rate, a control unit for controlling the pressure and flow rate of the gas to be supplied, and a gas to be supplied. Pressure adjusting means for adjusting the pressure of the gas in the pipeline to adjust the flow rate of the gas, and flow rate adjusting means for adjusting the flow rate of the gas to be supplied, and the flow rate adjusting means is provided with a flow rate setting means. An air supply device that can be adjusted according to a flow rate set value of the air supply device.

In this additional item, the flow rate adjusting means is adjusted in accordance with the flow rate set value.

(7) The air supply device according to the above item 6, wherein the flow rate adjusting means is an adapter detachable from an air supply base of the air supply device.

In this supplementary item, the flow rate can be adjusted by an adapter which is detachably attached to the air supply mouthpiece.

(8) In a device for injecting gas into a living body of a human body or an animal, a pressure sensor for measuring gas pressure in a pipe, and a gas pressure in a pipe for adjusting a flow rate of gas to be sent. Pressure adjusting means for adjusting the pressure, a valve for opening and closing the pipe, and a control unit for controlling the pressure and flow rate of the gas to be supplied, the control unit, after closing the valve, the pipe An air supply device characterized in that the pressure measurement time is changed based on the pressure drop characteristic in the inside. This additional item adjusts the pressure measurement time based on the pressure drop characteristic.

(9) The air supply device according to the above item 7, wherein the adjustment value of the pressure regulator is changed based on the pressure drop characteristic detected by the control unit. The pressure adjustment means brain adjustment value is adjusted based on the characteristic.

(10) The air supply device according to the above item 8, wherein the operation of the exhaust valve is controlled based on the pressure drop characteristic detected by the control section. Based on this, the operation of the exhaust valve is controlled.

[0069]

As described above, according to the present invention, there is an effect that the accuracy of a low flow rate can be ensured at a low cost without lowering the maximum gas flow rate.

[Brief description of the drawings]

FIG. 1 to FIG. 4 relate to a first embodiment of the present invention, and FIG. 1 shows an apparatus and a use state when performing an endoscopic operation using a medical endoscope system. Illustration

FIG. 2 is an explanatory diagram showing a configuration of an air supply device.

FIG. 3 is a perspective view showing an appearance of an air supply device.

FIG. 4 is a graph for explaining the relationship between the supply current of the electropneumatic proportional valve and the flow rate of the supplied gas.

FIG. 5 is a graph showing the relationship between the supply current of the electro-pneumatic proportional valve and the gas output pressure of the electro-pneumatic proportional valve, showing the second method of use.

FIG. 6 is a graph showing gas pressure in the case of a combination of a normal diameter endoscope and a trocar and in the case of a combination of a small diameter endoscope and a trocar;

FIG. 7 is a graph showing a pressure when the exhaust valve is released and a pressure when the exhaust valve is not released.

FIG. 8 is an explanatory diagram showing a configuration of an air supply device according to a second embodiment of the present invention.

FIG. 9 is an explanatory diagram showing a configuration of an air supply device according to a third embodiment of the present invention.

FIG. 10 is a graph illustrating the relationship between the supply current of the electropneumatic proportional valve and the flow rate of the supplied gas.

FIG. 11 is a partial explanatory view showing a configuration of an air supply device according to a fourth embodiment of the present invention.

[Explanation of symbols]

 2: endoscope 5: air supply device 6: trocar 7: trocar 8: insufflation tube 9: valve unit 10: knob 11: shaft 12: variable throttle 13a: pipes with different resistance values 13b: pipes with different resistance values Channel 53: High-pressure gas supply tube 54: Gas supply gas cylinder 55: Control unit 56: Internal conduit 57: Setting display unit 91: First pressure gauge 92: Primary decompressor 93: Electropneumatic proportional valve 94: First valve 95: flow rate measuring unit 96a: first pressure sensor 96b: second pressure sensor 97: second valve 100: exhaust valve

Claims (1)

[Claims] 1. An air supply device for injecting gas into a living body of a human or animal body, comprising: a control unit for controlling pressure and flow rate of gas to be supplied; flow rate setting means for setting a flow rate of gas to be supplied; Pressure adjusting means for adjusting the gas pressure for adjusting the flow rate of the gas to be sent, preliminary pressure adjusting means for variably adjusting the pressure of the gas input to the pressure adjusting means, or the gas downstream of the pressure adjusting means. Resistance adjusting means for variably adjusting the flow resistance, wherein the output pressure of the preliminary pressure adjusting means or the resistance value of the resistance adjusting means can be adjusted according to the set value by the flow rate setting means. Qi device.