JPH0556743B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to medical gases, such as oxygen, laughing gas, compressed air, nitrogen, etc., for identifying the types of medical gases used in medical facilities such as hospitals. This invention relates to a gas identification device.

BACKGROUND ART Conventionally, in medical facilities such as hospitals, a configuration has been used in which medical gases from multiple types of medical gas sources are supplied to medical equipment through outlets individually corresponding to each medical gas. . Each outlet corresponding to each medical gas is configured not to be connected to other medical gas equipment. With this configuration, medical errors due to incorrect connection of medical gas are prevented as much as possible.

In such prior art, if a gas source that individually supplies medical gas to each outlet is incorrectly connected, even if the medical gas user has correctly connected each outlet, the medical gas may not be the expected medical gas. Different medical gases will be supplied.
Furthermore, due to incorrect connections in the piping system from the medical gas source to the outlet, or due to mixing of different types of medical gas, a situation may occur in which the expected medical gas is not supplied from the corresponding outlet.

Problems to be Solved by the Invention An object of the present invention is to provide a medical gas identification device that can accurately identify medical gas and ensure that the expected medical gas is supplied to the desired location. It is.

Means for Solving the Problems The present invention provides outlet detection/identification means for supplying a plurality of types of medical gases from different outlets corresponding to each other, and for detecting the outlets and identifying the types of gases. , a gas detection means for detecting the type of medical gas supplied through the outlet based on a plurality of characteristics and its composition; responsive to each output of the outlet detection/identification means and the gas detection means; A medical gas identification device comprising means for determining whether the types of gases represented by the outputs are the same, and means for displaying the composition of the gas in response to the output from the gas detection means. .

In a preferred embodiment, the medical gas is oxygen,
Laughing gas, air, and nitrogen, and the composition of the gas displayed by the display means is oxygen.

OPERATION According to the present invention, there is provided a means for detecting the outlet through which each type of medical gas is individually supplied, and a method for determining the type of medical gas passing through the outlet based on a plurality of characteristics (e.g., thermal conductivity and oxygen concentration). Since the gas type is detected and the type of gas is identified based on the output from the gas detection means for detecting its composition, the type of gas can be identified without error. Furthermore, when the gas identified by the output from the gas detection means is a mixed gas, the composition ratio of oxygen, etc. can be displayed by the display means, thereby improving patient safety.

Embodiment FIG. 1 is a block diagram showing the electrical configuration of an embodiment of the present invention. Thermal conductivity, which is a common characteristic of medical gases such as oxygen, laughing gas, and compressed air used in medical facilities such as hospitals, is detected by a so-called thermal conduction type detection means 1. Further, the oxygen concentration of these gases is detected by the oxygen detection means 2. Outputs from the thermal conduction type detection means 1 and the oxygen detection means 2 are given to a processing circuit 3 realized by a microcomputer or the like.

FIG. 2 is a graph for explaining the principle of the present invention. The vertical axis shows the output of the thermal conduction type detection means 1, and the horizontal axis shows the oxygen concentration of the gas measured by the output of the oxygen detection means 2. Point A indicates pure oxygen, point B indicates laughing gas, and point C indicates nitrogen. Air contains 21% oxygen and is indicated by point D. Point A,
A straight line l1 connecting points B represents a mixed gas consisting of oxygen and laughing gas, a straight line l2 connecting points A and D represents a mixed gas of oxygen and air, and a straight line l3 connecting points B and D
indicates a mixture of air and laughing gas. Also line l
4 is a straight line connecting points B and C, and represents the characteristics of a mixed gas of laughing gas and nitrogen. The outputs from the thermal conduction type detection means 1 for air and nitrogen are similar, and therefore, there is a risk of false detection if only this is used. However, in the present invention, the output from the oxygen detection means 2 is also used. Therefore, such false detection can be prevented as much as possible.

Point E within the triangular area connecting points A, B, and C is the thermal conduction type detection means 1 and the oxygen detection means 2.
, the oxygen concentration H at point E can be detected by the oxygen detection means 2, and the mixing ratio of the remaining gases, laughing gas and nitrogen, can be determined by the following equations: As shown in equation 2.

N ₂ O=e−g/f−g(100−H) ……(1) N ₂ =fe/f−g(100−H)……(2) Here, N ₂ O is the _N2 indicates the concentration of nitrogen.

In this way, the output of the thermal conduction type detection means 1,
Based on the output from the oxygen detection means 2, the type of gas and its composition can be calculated and determined.

FIG. 3 is a piping system diagram of one embodiment of the present invention. In the medical installation, outlets 4, 5, 6 located at fixed locations supply oxygen, laughing gas and compressed air. The pressure of these gases is
For example, it is 4.5Kg/ ^cm2 . One or more types of gas from these outlets 4, 5, 6 are
The mixture is guided from the mixing means 7 to a circulation line 8 at a pressure of approximately atmospheric pressure, and is supplied to a patient's mask 9. A stretchable breathing bag 10 is connected to the circulation line 8 . Gas from the mask 9 performs anesthesia, artificial respiration, and the like.

Using the gas identification device 11 according to the present invention, the type and composition of gas flowing into the circulation pipe 8 can be detected at all times, and in addition, the type and composition of the gas supplied from the outlets 4, 5, and can be identified. Gas identification device 1
1 has pipe joints 14, 15 connected to the circulation pipe 8 via pipes 12, 13, and also has a pipe joint 16 connected to the outlets 4, 5, 6.
The gas from the pipe joint 16 flows from the throttle 17 to the pipe line 18.
is guided to filter 19, and this filter 1
The gas from 9 is given to the thermal conduction type detection means 1 and the oxygen detection means 2, and then led out to the pipe joint 15. Gas from the pipe joint 14 is sucked from a pipe line 20 by a pump 23 through a three-way valve 21, which is an electromagnetic valve, from a pipe line 22, and is forced into the pipe line 18 via a check valve 24. This gas identification device 11 is
It has a conduit 26 having an open end 25, and this conduit 2
6 is connected to the three-way valve 21. The three-way valve 21 is
This is achieved by switching between a first connection state in which the pipes 20 and 22 are connected and the pipe 26 is cut off, and a second connection state in which the pipes 22 and 26 are connected and the pipe 20 is cut off.

FIG. 4 is a front view of the gas identification device 11, and FIG. 5 is a side view of the gas identification device 11. The front panel 27 of the gas identification device 11 is provided with lamps 28 to 31 that light up individually corresponding to oxygen, laughing gas, compressed air, and nitrogen. In addition, there is a display 32 for digitally displaying oxygen concentration, a switch 33 for zero adjustment, and a power switch 34.
Switch 36 for stopping the buzzer 35 from ringing
and a switch 37 for operating the pump 23. A lamp 38 is provided in association with the zero adjustment switch 33, which lights up during the zero adjustment operation. Pipe lines 12, 13 to pipe fittings 14, 15
The detection means 39 detects that the two are connected.

FIG. 6 is a side view of the outlet adapter 40 used in conjunction with the gas identification device 11.
The pipe fitting 41 is detachably connected to the pipe fitting 16 attached to the gas identification device 11 . The fittings 42 of the outlet adapter 40 can be fitted and connected to the outlets 4, 5, 6. Outlets 4, 5 and 6 are detected by outlet detection means 43, the output of which is led out from line 44 to connector 45. The connector 45 is detachably connected to a connector 46 provided on the gas identification device 11. Gas from pipe fitting 42 passes from pipe line 47 to pipe fittings 41 and 16 and is used for gas identification.

The operation will be explained with reference to FIG. step
When the power switch 34 is turned on at n1,
In step n2, initial settings are performed, and operations such as turning on the power lamp 48 are performed.
In step n3, switch 3 for zero adjustment is
It is determined whether or not 3 has been operated, and if so, the process moves to step n4, and the lamp 38 remains lit. In step n5, the three-way valve 21 is operated to connect the pipes 22 and 26, and the pipe 20 is cut off. In step n6, the pump 23 is operated and atmospheric air is sucked through the open end 25. Step n7 waits for the operating state to continue for 10 seconds. In this way, the atmosphere is supplied from the check valve 24 to the heat conduction type detection means 1 and the oxygen detection means 2 via the pipe line 18 and the filter 19. At step n8, the data detected by the thermal conduction type detection means 1 is stored in the memory of the processing circuit 3. At step n9, the data detected by the oxygen detection means 2 is stored in the memory.
In step n10, the drive circuit 49 displays the oxygen concentration detected by the oxygen detection means 2 on the display 3.
2. The oxygen concentration displayed at this time is the oxygen concentration in the atmosphere, which is 21%.
In step n11, the processing circuit 3 detects point D in FIG. 2 based on the outputs from the thermal conduction type detection means 1 and the oxygen detection means 2, and thereby lights up the lamp 30 indicating that it is air. . Then step
The pump 23 is stopped at step n12, and then the three-way valve 21 is demagnetized at step n13. By demagnetizing the three-way valve 21, the conduits 20 and 22 are brought into a connected state, and the conduit 26 is cut off. At step n14, the lamp 38 indicating that the zero adjustment operation is in progress is turned off. In this way, the calibration operation is completed and the process moves to step n15.

In order to identify the type of gas supplied from the outlets 4, 5, and 6 and its composition using the outlet adapter 40, the following operation is performed. In step n15, when it is determined that the pipe joint 41 of the outlet adapter 40 is connected to the pipe joint 16 of the gas identification device 11, and that the connectors 45 and 46 are also connected, the process moves to step n16, where zero adjustment is performed. It is determined whether the execution has been completed, and if not, the process moves to step n17, where the lamp 38 for zero adjustment is blinked and the buzzer 35 is sounded. If the zero adjustment has been completed, the process moves to step n18, where it is determined whether the pipe joint 42 is connected to one of the outlets 4, 5, and 6. After these connections are made, proceed to step n19 and connect the lamp 2 corresponding to the type of gas.
8 to 31 are blinking. This will display that the gas identification operation is being performed. In step n20, the outlet detection means 4
Based on the output from the outlet 3, the type of gas corresponding to the outlet 4, 5, 6 to which the pipe joint 40 is connected is identified and stored in the memory. In step n21, it is determined whether the outlets 4, 5, and 6 detected by the output from the outlet detection means 43 are outlets corresponding to predetermined oxygen, laughing gas, and compressed air. The process moves to step n22, and unless the buzzer 35 has stopped, the process moves to step n23, where the buzzer 35 is sounded to generate an alarm sound.

After waiting for 5 seconds in step n24, in step n25, the type of gas having a thermal conductivity corresponding to the type of gas is determined based on the output from the thermal conduction type detection means 1, and the content thereof is stored in the memory. In step n26, based on the output from the oxygen detection means 2, it is detected whether the gas contains oxygen and what the oxygen concentration is, and these are stored in the memory. In step n27, it is determined whether the types of gas represented by the respective outputs from the thermal conduction type detection means 1, the oxygen detection means 2, and the outlet detection means 43 match, and if so, they are detected and identified in step n28. One of the lamps 28, 29, 30, 31 corresponding to the selected gas is lit, and in step n29, the oxygen concentration is displayed on the display 32, and the process moves to step n34. When the respective outputs of the three detection means 1, 2, and 43 described above do not match,
Move from step n27 to step n30 and turn on lamp 2.
8 to 31 continue to blink, and the process moves to step n31, where the display means 32 displays the oxygen concentration detected by the oxygen concentration detection means 2. In step n32, unless the buzzer stop switch 36 is activated, the buzzer 35 is sounded in step n33, and the process moves to step n34.

The gas identification device 11 is connected to the circulation pipe 8 in the pipe 1.
2 and 13, and the following operations are performed to detect the type of gas and oxygen concentration during patient treatment. When the detection means 39 detects in step n34 that the pipe joints 14 and 15 are connected to the pipe lines 12 and 13, the process moves to step n35, where it is determined whether the zero adjustment has been completed. If the adjustment is completed and not completed, the process moves to step n36, where the zero adjustment lamp 38 flashes and the buzzer 35 sounds. If the zero adjustment is completed, proceed to step n37, lamps 28 to 31 will blink, and step n37 will proceed.
In n38, switch 37 is operated and pump 23
It is determined whether the is working or not. When the pump 23 is operating, the process moves to step n39, and after maintaining that state for one second, the oxygen concentration of the gas detected by the oxygen detection means 2 is detected in step n40, and the data is stored in the memory. do.
In step n41, the oxygen concentration detected by the oxygen detection means 2 is displayed on the display 32. In step n42, it is determined whether the detected oxygen concentration is 18% or less, and if so, the buzzer 35 is sounded in step n44 unless the buzzer stop switch 36 is activated in step n43.

In step n45, the data detected by the thermal conduction type detection means 1 is stored in the memory. In step n46, the above-mentioned equations 1 and 2 are calculated based on the outputs from the thermal conduction type detection means 1 and the oxygen detection means 2 to determine the type of gas. For example, during anesthesia, a mixed gas of oxygen and laughing gas is used, and during artificial respiration, a mixed gas of oxygen and air, that is, a mixed gas of oxygen and nitrogen is used. Therefore, it can be determined whether a gas having a mixed composition suitable for anesthesia is being supplied or a gas having a composition suitable for artificial respiration is being supplied. In step n47, lamps 28 to 3 corresponding to the composition of gas suitable for anesthesia or artificial respiration are selected.
Turn on 1. For example, when a gas suitable for anesthesia is being supplied, a lamp 28 corresponding to oxygen
and the lamp 29 corresponding to laughing gas are turned on. Further, when gas suitable for artificial respiration is being supplied, the lamp 28 corresponding to oxygen and the lamp 30 corresponding to air are turned on. Furthermore, when other gases are being supplied, one or more lamps 28 to 31 are turned on. Return from step n47 to step n38.

In this way, the type and composition of gas actually used during patient treatment can be constantly inspected.

FIG. 8 is an electric circuit diagram showing a specific configuration of the thermal conduction type detection means 1. FIG. Fixed resistance 51, 52
and resistors 53 and 54 having a large temperature resistance coefficient constitute a bridge circuit. A variable resistor 55 is connected in connection with this bridge circuit. One resistor 53
is provided in air as a standard gas. Another resistor 54 is provided in a space 56 through which the gas to be identified flows, which is supplied from line 18 via filter 19 in FIG. The resistance value of the variable resistor 55 is set so that when air exists in the space 56, the outputs of the lines 57 and 59 are zero. In this way, an output level corresponding to the thermal conductivity of the gas flowing in the space 56 is derived from the lines 57 and 59, thereby making it possible to detect the type of gas.

A specific configuration of the oxygen detection means 2 is shown in FIG. This oxygen detection means 2 is known as a so-called galvanic cell type oxygen sensor, and a noble metal electrode 61 such as Au or Pt and a base metal electrode 62 such as Fe, Zn or Pb are electrolyzed in a container 60. The battery is immersed in a liquid 63 and the electromotive force generated naturally by the battery is utilized to determine the current associated with oxidation-reduction. A gas permeable membrane 64 is provided in the electrolytic solution 63 in the container 60 . This gas permeable membrane 64
is made of fluororesin such as Teflon (trade name). A gas permeable membrane 64 is used to supply oxygen in the gas to be measured to the electrodes 61 and 62 at a constant rate.
is provided in close contact with the gas and electrolyte 63. There is a correlation between the current flowing between the electrodes 61 and 62 and the oxygen concentration in the gas that contacts the gas permeable membrane 64.

Next, the outlet detection means 43 and its related configuration will be explained with reference to FIGS. 10 to 14.

FIG. 10 is a sectional view of the outlet 4.
The body 66 is connected to a source of oxygen. This gas is supplied from the filter 67 to the valve chamber 68 . The valve body 69 is biased by a spring 70 in the valve chamber 68, and a spring force is applied to the seal member 71 in the direction of closing the valve. The valve body 69 has a protrusion 72 . A sealing member 73 made of a material such as rubber is arranged near the outer periphery of the protrusion 72 . A locking member 74 that is screwed and fixed to the main body 66 has a claw 75 . At the free end of this locking member 74,
The abutment member 76 is fixed.

The shape of the contact member 76 seen from the front is as shown in FIG. Fitting holes R1 to R5 are formed on the front surface of the contact member 76 in correspondence with oxygen, laughing gas, and air. When oxygen is supplied to the outlet 4, the front surface of the contact member 76 has fitting holes R1, which are formed at positions shifted by 180 degrees from each other.
Only R2 is formed. When laughing gas is supplied to the outlet 5 having the same configuration as the outlet 4, the front of the abutment member 76 of the outlet 5 has a fitting hole R1 and a hole 135 degrees circumferentially offset from the fitting hole R1. A fitting hole R3 is formed at the position. Furthermore, when air is supplied to the outlet 6, the front surface of the contact member 76 has fitting holes R1, R4,
R5 is formed.

FIG. 12 is a perspective view of the adapter 78 to which oxygen is to be supplied from the outlet 4. Pipe fitting 7
9 is inserted from the center hole 80 of the abutment member 76, this pipe joint 79 is inserted into the valve body 6 of the outlet 4.
The protrusion 72 of 9 is pushed against the spring 70, and the sealing member 73 is brought into close contact with the outer peripheral surface of the pipe joint 79. The claw 75 is resiliently engaged with the engagement groove 81 of the pipe joint 79, thereby preventing the pipe joint 79 from coming off.
The pins Q1 and Q2 formed on the adapter 78 fit into the fitting holes R1 and R2 formed on the front surface of the abutment member 76.
This ensures that the adapter 78 is connected to the outlet 4 for oxygen and is not accidentally connected to the outlets 5, 6 for other gases. A flexible tube 83 or the like is connected to the adapter 78 and guided to a medical device.

FIG. 13 1 shows the front side of an adapter 78 for a medical device to be supplied with oxygen, with pins Q1 and Q2 mated as described above. Further, pins Q1 and Q3 are formed on the adapter 84 to which laughing gas is to be supplied, as shown in FIG.
3, respectively. The adapter 85 for the medical device to which air is to be supplied is formed with pins Q1, Q4, and Q5, as shown in FIG. 13, which fit into the fitting holes R1, R4, and R5, respectively. . In this way, it becomes possible to supply each type of gas to the adapters 78, 84, and 85 without error.

FIG. 14 is a sectional view of the outlet detection means 43. The pipe fitting 42 has a portion that fits into the central hole 80 of the outlet 4, and has a structure similar to that of the adapter 78 shown in FIG. 12 described above. Fixing pins V1 are fixed to the base end 86 of the pipe joint 42 in correspondence with the fitting holes R1 of the outlets 4, 5, and 6 for each type of gas, and fixing pins V1 are fixed in correspondence with the fitting holes R2 of the outlets 4, 5, and 6 for each type of gas. Movable pin V2 is attached. This movable pin V2 is urged by a spring 87 to protrude outward. Movable pin V2 is
It is linked to the actuator 89 of the micro switch 88. Similarly, movable pins are provided corresponding to the fitting holes R3 and R4, thereby providing micro switches whose switching modes can be changed.

When the pipe joint 42 is connected to the outlet 4 for supplying oxygen, the movable pin V2 of the outlet detection means 43 fits into the fitting hole R2, the switching mode of the micro switch 88 does not change, and the remaining fitting hole The movable pins corresponding to R3 and R4 contact the front surface of the contact member 76 and elastically move the first
4 and is recessed to the left in FIG. 4, thereby changing the switching mode of the microswitch by the movable pins relative to the fitting holes R3 and R4. In this way, in response to the output of the micro switch 88, it is possible to identify in the processing circuit 3 which outlet 4, 5, or 6 is supplied with oxygen, laughing gas, or air. Become.

The outlet detection means 43 may be realized by other configurations.

Instead of the thermal conduction type detection means 1, focusing on the fact that the refractive index of light, which is a common characteristic of the gases to be detected, corresponds individually to the type of each gas and its composition, the refractive index can be measured optically. It may be configured to detect the type and composition of the gas, or may be realized by other configurations.

Although the oxygen detection means 2 is a so-called galvanic cell type oxygen sensor in the above embodiment, it may be a zirconia type oxygen sensor in other embodiments, or may have other configurations. It may be.

FIG. 15 is a front view of another embodiment of the invention. This embodiment is similar to the previous embodiment, and corresponding parts are given the same reference numerals. In the display device of this embodiment, the light emitting diodes A, B, C, and D correspond to the points A, B, C, and D described in connection with FIG.
B, C, and D are provided and are turned on based on the detection result of the gas concentration. In the display area 92 of this display, the oxygen concentration and the laughing gas concentration are digitally displayed. The other configurations are similar to those of the previous embodiment.

FIG. 16 is a front view of still another embodiment of the present invention. This example is similar to the previous example,
Corresponding parts are given the same reference numerals. In this embodiment, the adapter 40 (first
2), the pipe joint 42 and the outlet detection means 43 are attached to the gating 93.

Effects As described above, according to the present invention, medical gas can be detected without error, and therefore, necessary medical gas can be supplied without error.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the electrical configuration of an embodiment of the present invention, FIG. 2 is a graph for explaining the principle of the present invention, and FIG. 3 is a piping system diagram of an embodiment of the present invention. 4 is a front view of the gas identification device 11 according to an embodiment of the present invention, FIG. 5 is a side view of the gas identification device 11, FIG. 6 is a side view of the adapter 40, and FIG. 7 is a diagram for explaining the operation. Flowchart, FIG. 8 is an electric circuit diagram showing the configuration of the thermal conduction type detection means 1, FIG.
10 is a sectional view of the outlet 4, FIG. 11 is a front view of the contact member 76, FIG. 12 is a perspective view of the adapter 78, and FIG.
The figure is a front view of adapters 78, 84, 85, No. 14.
The figure is a sectional view of the outlet detection means 43, the 15th
The figure is a front view of another embodiment of the invention, and FIG. 16 is a front view of still another embodiment of the invention. DESCRIPTION OF SYMBOLS 1... Thermal conduction detection means, 2... Oxygen detection means, 3... Processing circuit, 4, 5, 6... Outlet, 7... Mixing means, 9... Mask, 11... Gas identification device, 14 , 15, 16...pipe joint, 19
... Filter, 21 ... Three-way valve, 23 ... Pump, 28-31 ... Lamp, 32 ... Display, 4
0...Outlet adapter.

Claims (1)

[Scope of Claims] 1. Outlet detection/identification means for supplying a plurality of types of medical gases from individually corresponding, mutually different outlets, detecting the outlets and identifying the types of gases, and via the outlets. a gas detection means for detecting the type of medical gas to be supplied based on a plurality of characteristics and its composition; responsive to the outputs of the outlet detection/identification means and the gas detection means; A medical gas identification device comprising: means for determining whether the gases are of the same type; and means for displaying the composition of the gas in response to an output from the gas detection means. 2. Medical gas identification according to claim 1, wherein the medical gas is oxygen, laughing gas, air, and nitrogen, and the composition of the gas displayed by the display means is oxygen. Device.