JPH049545B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an artificial respirator used to perform respiratory functions for patients who have temporarily stopped breathing or are unable to breathe adequately. It is an object of the present invention to provide a respirator which is simple in structure and operation and therefore can be widely implemented.

FIG. 1 is a system diagram of an embodiment of the present invention, and FIG. 2 is an operating waveform diagram thereof. Intake gas from an intake gas pressure source 1 , for example, intake gas such as oxygen or air, is supplied from a pressure reducing valve 2 to a first switching valve 7 . From the normal position D of the first switching valve 7, the pilot port 8b provides pilot pressure in the direction of the offset position G of the second switching valve 8.
A pilot pressure is applied through the flow path 9.

FIG. 2 1 shows the normal position F of the second switching valve 8.
FIG. 2 shows the time course of the pilot pressure in the pilot port 8b, and FIG. 2 shows the time course of the pilot pressure in the pilot port 8b, and FIG. FIG. 2 shows the passage of time for the pilot port 7a where the pilot pressure is applied in the direction of the change-over valve 7, and FIG. The flow path 15 connected to the pilot port 7b is connected to the flow paths 82 and 21. When the second switching valve 8 is at the offset position G, the flow path 2
4 is connected to the flow path 21 , and intake gas is supplied to the mask 4 via the flow path 82 and the aperture 13 . The mask 4 has a check function that provides inhaled gas to the patient and releases exhaled gas into the atmosphere. During the intake time Tin from time t0 to t1, the intake gas from the pressure reducing valve 2 passes through the flow path 6, moves from the normal position D of the first switching valve 7 to the pilot port 8b of the second switching valve 8 via the flow path 9. Given as pilot pressure. As a result, the second switching valve 8 is connected to the offset position G. The pilot pressure through the normal position D of the first switching valve 7 is applied to the pilot port 8a and the second tank 23 from the throttle 49 through the flow path 80, and thereby the pilot pressure is applied to the pilot port 8a and the second tank 23 as shown in FIG.
The pilot pressure at a increases over time. The intake gas flowing from the pressure reducing valve 2 through the flow path 24 is
From the offset position G of the second switching valve 8 to the flow path 2
1 and 15 to the pilot port 7b of the first switching valve 7, and from flow paths 82 and 17 to the pilot port 7a and the first switching valve 7 via the check valve 16.
tank 22. Therefore, the first switching valve 7 is maintained in the connected state at the normal position D by the spring force. The intake gas from the flow path 21 is given to the mask 4 from the flow path 82 through the aperture 13,
The patient is inspired. Pilot port 7
Tanks 22 and 23 are connected to a and 8a.

As shown by the solid line in FIG. 2, the pilot pressure at the pilot port 8a of the second switching valve 8 increases, and at time t1, the pilot pressure at the pilot port 8b includes the spring force for performing an offset operation. When the operating pressure P2 reaches a lower value, the second switching valve 8 switches to the normal position F at time t1. Therefore, the flow path 21 is opened to the atmosphere. Therefore, the pilot port 7b of the first switching valve 7 is opened to the atmosphere via the flow paths 15 and 21. At this time, the first switching valve 7 is connected from the normal position D to the offset position E after time t1, thereby opening the flow paths 80 and 90 to the atmosphere. Therefore, one pilot port 8a of the second switching valve 8
is opened to the atmosphere through the check valve 31 and the flow path 80, and the other pilot port 8b is opened to the atmosphere through the flow path 9. Therefore, the second switching valve 8
is maintained in the connected state at the normal position F. Time t
1 and thereafter, the pilot pressure in the pilot port 7a of the first switching valve 7 gradually decreases as shown by the solid line in FIG. 2 due to the action of the throttle valve 48 and the first tank 22. The pilot pressure of the pilot port 7a of the first switching valve 7 is the same as that of the first switching valve 7.
When the operating pressure decreases to P1, the first switching valve 7
switches to the normal position D again at time t2. In this way, exhalation is performed during the expiration time Tex from time t1 to t2, and after time t2, the second switching valve 8 is in the normal position,
Inhalation is performed again.

When the secondary pressure of the pressure reducing valve 2 is adjusted and increased, the waveform changes as shown by the imaginary line in FIG. done in time. By increasing the secondary pressure of the pressure reducing valve 2, the tidal volume of intake gas to the mask 4 via the throttle 13 increases, and at this time, the inhalation time and exhalation time become longer and the respiration rate becomes smaller. Therefore, by selecting the secondary pressure of the pressure reducing valve 2 according to the weight of the patient wearing the mask 4, appropriate artificial respiration can be performed. Therefore, it is easy to operate.

The intake time Tin is the secondary pressure of the pressure reducing valve 2, P and R.
1, R2 is the resistance of the throttle 49, 48, C1, C2 is the volume of the tanks 23, 22, and ΔP is P2=P1−ΔP…(1), then Tin=R1・C1P−ΔP−P1/P− It is expressed as ΔP+1 (2). Further, the exhalation time Tex is expressed by the following formula.

Tex=R2・C2P−ΔP+1/P2+1 (3) As another embodiment of the present invention, the mask 4 is connected to the connection point 83 (see FIG. 1) of the flow channels 9 and 80 via the aperture 13, and the flow The connection between the connection point 84 of the passages 82 and 17 and the diaphragm 13 may be disconnected.

FIG. 3 is a system diagram of another embodiment of the present invention,
FIG. 4 is a diagram of its operating waveforms. In Figure 3, the first
Corresponding parts of the figures are given the same reference numerals. A noteworthy feature is that the first switching valve 7 has 5 ports,
At the normal position D, the flow path 81 communicating with the mask 4 via the diaphragm 13 is opened to the atmosphere,
During the exhalation time Tex, exhalation is performed. Inhalation time Tin
Inside, the first switching valve 7 is connected to the offset position E, and intake gas is supplied from the flow path 6 to the flow path 81. At this time, the flow path 80 and the pilot port 8b of the second switching valve 8 are The offset position E is opened to the atmosphere.

FIG. 41 shows the time course of the pilot port 8a of the second switching valve 8, FIG. 42 shows the change in pilot pressure of the pilot port 8B, and FIG.
4 shows the time course of the pilot pressure at the pilot port 7b of the first switching valve 7. FIG. 4 shows the time course of the pilot pressure at the pilot port 7b of the first switching valve 7. The operation of the embodiment shown in the third figure is similar to the embodiment shown in the first figure described above.

In the embodiment shown in the third figure, two parts of the pressure reducing valve 2 are also
By setting the next pressure, the tidal volume, expiration time, and respiration rate according to the expiration time can be set to optimal values, and there is an advantage that the operation is easy.

In the embodiment shown in FIG. 3, the inspiratory gas flowing from the pressure reducing valve 2 through the channels 6, 24 during the expiration time Tex is used only as a pilot fluid for the first and second switching valves 7, 8. This exhalation time Tex
At this time, the intake gas from the pressure reducing valve 2 is not supplied to the mask 4, and during the intake time Tin, the flow passage 6 and the flow passage 81 are connected to the mask 4 at the offset position E of the first switching valve 7. , intake gas is supplied through the throttle 13. During this intake time Tin, the flow path 24 is blocked at the normal position F of the second switching valve 8. Therefore, the intake time Tin and the intake time Tex are unrelated to the flow rate of the intake gas supplied from the flow path 81 to the mask 4. Therefore, even when a so-called low-accuracy pressure reducing valve 2 whose secondary pressure changes greatly depending on the flow rate is used, the intake time Tin and the intake time Tex are accurate.
Breathing rate will be maintained accurately. Moreover,
Even when the secondary pressure of the pressure reducing valve 2 is increased to increase the tidal volume and respiratory rate,
Regardless of the increase in tidal volume, the respiratory ratio (= inspiratory time
Tin/expiration time Tex) can be kept almost constant. Therefore, the breathing ratio should be set in the optimal range 1/
It is possible to always keep it between 1.5 and 2.

The pressure reducing valve 2 may have a structure that continuously changes the spring force for setting the secondary pressure, thereby making it possible to continuously change the tidal volume and respiratory rate within an optimal range. can.

Inhalation time Tin is expressed by the following formula.

Tin=R2・C2lnP+1/P2+1…(4) The exhalation time is expressed by the following formula.

Tex=R1.C1P-P1/P+1 (5) FIG. 5 is an overall system diagram of still another embodiment of the present invention, and FIG. 6 is a waveform diagram for explaining its operation. Parts corresponding to those in the previous embodiment are given the same reference numerals. Intake gas from the intake gas pressure source 1 is supplied from the pressure reducing valve 2 to the first switching valve via the flow path 85 and also to the second switching valve 8 . The pilot pressure from the flow path 85 is applied from the normal position D of the first switching valve 7 to the pilot port 8b of the second switching valve 8 via the flow path 9 after time t0 in FIG. The time course of the pilot pressure in the flow path 9 and the pilot port 8b is shown in FIG. 62. Pilot pressure from the flow path 85 via the normal position D is applied to the pilot port 8a and the second variable volume tank 45 via the throttle 49. The pilot pressure in the pilot port 8a increases over time during the exhalation time Tex from time t0 to time t1, as shown in FIG. 6. In this way, the pilot pressure in the direction where the second switching valve 8 reaches the normal position F is applied to the pilot port 8a.
A pilot pressure in the direction of the offset position G of the second switching valve 8 is applied to the pilot port 8b. Expiration time from this time t0 to t1
During Tex, the second switching valve 8 is connected to the offset position G. Therefore, the pilot pressure from the flow path 85 is from the offset position G to the flow path 2.
The water is supplied from the flow path 15 to the pilot port 7b of the first switching valve 7 via the flow path 17, and from the check valve 16 to the pilot port 7a and the first variable volume tank 44 via the flow path 17. Pilot pressure in a direction that brings the first switching valve 7 to the offset position E is applied to the pilot port 7a, and pilot pressure in a direction that brings the first switching valve 7 to the normal position D is applied to the pilot port 7b.
As a result, the first switching valve 7 remains connected to the normal position D during the exhalation time Tex due to the force of the spring provided in the first switching valve.

The pilot pressure of the pilot port 8a is
At time t1 when the operating pressure P2 of the second switching valve 8 reaches a value lower than the pilot pressure of the pilot port 8b shown in FIG. As a result, the connection state is reached at the normal position F. Therefore, the flow paths 21 and 15 are opened to the atmosphere, and as a result, the pilot pressure in the pilot port 7b is released as shown in FIG. 6. Although the flow paths 21 and 17 are also opened to the atmosphere at the same time, the pilot pressure in the pilot port 7a is controlled by the throttle 48 and the first variable volume tank 44.
As shown in FIG. 6, it decreases over time due to the action of . Until t2 when the pilot pressure in the pilot port 7a is higher than the pressure P1 corresponding to the force of the spring provided in the first switching valve 7, the first
The switching valve 7 is held at the offset position E. At this time, the flow path 9 is at the offset position E of the first switching valve 7.
It is opened to the atmosphere by Pilot port 8b
is opened to the atmosphere. Further, the pilot port 8a is opened to the atmosphere via a check valve 31. In this way, the second switching valve 8 is maintained at the normal position F.

When the pilot port 7a of the first switching valve 7 reaches the operating pressure P1 of the first switching valve 7 at time t2, the first switching valve 7 is returned to the normal position D by the force of the spring provided therein. becomes. During the intake time Tin from time t1 to t2, the intake gas from the flow path 85 is transferred to the pressure reducing valve 8.
6, is supplied to the mask 4 from the flow path 11 and the aperture 29 via the offset position E. Also, pressure reducing valve 8
The secondary pressure of 6 is from the flow path 53 to the variable volume tank 4.
4, 45 and control rooms 46, 47. 1st
In the variable capacity tank 44, the large diameter piston 5
0 and a small diameter piston 51 are connected by a connecting rod 52 in the control chamber 46, and the small diameter piston 51
A tank chamber 87 defined by is connected to the pilot port 7a of the first switching valve 7. The large diameter piston 50 is biased toward the tank chamber 87 by a spring 88 in a spring chamber 89 . This spring chamber 89 is open to the atmosphere. The second variable capacity tank 45 has the same structure as the first variable capacity tank 44, and has a large diameter piston 54 and a small diameter piston 55.
are connected by a connecting rod 56 in the control room 47, and the pilot port 8a of the second switching valve 8
A tank chamber 90 is connected to the tank chamber 90, and a spring 92 in a spring chamber 91 open to the atmosphere biases the large diameter piston 54 toward the tank chamber 90 side.

By increasing the secondary pressure of the pressure reducing valve 86, the flow rate to the mask 4 during the inhalation time Tin increases, and the tidal ventilation amount can be increased. When this secondary pressure is large, variable capacity tank 4
The large diameter pistons 50 and 54 of 4 and 45 are
8 and 92 to the left in FIG. 5, and at this time, the volumes of the tank chambers 87 and 90 are increased. Therefore, the rising speed of the pilot pressure applied to the pilot port 8a through the throttle 49 becomes smaller, and the exhalation time Tex from time t0 to t1 becomes longer, and the air is released into the atmosphere from the pilot port 7a through the throttle 48. The rate at which the pilot pressure decreases becomes slower, the time required for the decrease becomes longer, and the intake time Tin becomes longer. Therefore, the respiratory rate decreases. In this way, by adjusting the secondary pressure of the pressure reducing valve 86, the tidal volume is increased and the breathing rate is decreased, or the tidal ventilation volume is decreased and the breathing rate is increased. It is extremely easy to operate.

During the intake time Tin, intake gas from the pressure reducing valve 86 is supplied to the mask 4 from the flow path 11 via the offset position E of the first switching valve 7. During this inspiratory time Tin, the inspiratory gas from the pressure reducing valve 86 is not simultaneously used as a pilot pressure for determining the inspiratory time Tin and/or the expiratory time Tex. Also, during the expiration time Tex, a relatively small flow of intake gas from the flow path 85 is applied as pilot pressure to the pilot port 8a of the second switching valve 8 via the throttle 49. Therefore, the excellent advantage that the expiratory time Tex and the inspiratory time Tin are accurate is exhibited.

The secondary pressure from the pressure reducing valve 86 is not used as pilot pressure for the first switching valve 7 and the second switching valve 8. Therefore, the secondary pressure of the pressure reducing valve 86 can be set relatively low without considering the operating pressures P1, P2 of the switching valves 7, 8. Moreover, depending on the pressure-flow rate characteristics of the throttle 29, it is possible to greatly change the flow rate of the intake gas given to the mask 4 with a small amount of change in the secondary pressure of the pressure reducing valve 86.

When the secondary pressure of the pressure reducing valve 2 is adjusted and increased, the waveform changes as shown by the imaginary line in FIG. done in time. By increasing the secondary pressure of the pressure reducing valve 2, the tidal volume of intake gas to the mask 4 via the throttle 29 increases, and at this time, the inhalation time and exhalation time become longer and the respiration rate becomes smaller. Therefore, by selecting the secondary pressure of the pressure reducing valve 2 according to the weight of the patient wearing the mask 4, appropriate artificial respiration can be performed. Therefore, it is easy to operate.

As described above, according to the present invention, an artificial respiration device is realized with a simple structure and is easy to operate.

[Brief explanation of drawings]

FIG. 1 is a system diagram of one embodiment of the present invention, FIG. 2 is a waveform diagram for explaining the operation of FIG. 1, FIG. 3 is a system diagram of another embodiment of the present invention, and FIG. FIG. 3 is a waveform diagram for explaining the operation, FIG. 5 is an overall system diagram of still another embodiment of the present invention, and FIG. 6 is a waveform diagram for explaining the operation. DESCRIPTION OF SYMBOLS 1... Intake gas pressure source, 2, 86... Pressure reducing valve, 4... Mask, 7... First double piloted spring offset type 2-position switching valve, 8... Second double piloted spring offset type 2-position switching valve, 16,
31... Check valve, 22, 23... Tank, 44, 45
...Variable capacity tank, 48,49...Aperture, 87,9
0...Tank room, D, F...Normal position, E, G...
Offset position.

Claims (1)

[Scope of Claims] 1. From a first double piloted spring offset type 2-position switching valve (hereinafter referred to as the first switching valve) in the normal position to a second double piloted spring offset type 2-position switching valve ( A pilot pressure is applied in the direction of the offset position of the second switching valve (hereinafter referred to as the second switching valve), and the pilot pressure is applied to the second tank through the throttle in the direction of the normal position of the second switching valve and the offset position of the second switching valve. The pilot pressure is applied later than the pilot pressure in the direction, and the pilot pressure is applied in the direction from the first switching valve at the offset position to the offset position of the second switching valve and the normal position of the second switching valve is applied via the second check valve. and the pilot pressure in the second tank are simultaneously released, and the pilot pressure in the direction of the normal position of the first switching valve is released from the second switching valve at the offset position, and the pilot pressure of the first switching valve is released via the first check valve. Apply the pilot pressure in the direction of the offset position and the first tank at the same time, remove the pilot pressure in the direction of the normal position of the first switching valve from the second switching valve in the normal position, and also apply the pilot pressure in the direction of the normal position of the first switching valve to the first switching valve through the throttle. The first switching valve and the second switching valve are each provided with a spring, and the pilot pressure in the first tank is released later than the pilot pressure in the direction of the normal position of the first switching valve. When the same pilot pressure is applied by the spring in the direction of the normal position and the direction of the offset position, each switching valve is held in the normal position, and the pilot pressure in the direction of the offset position and the direction of the normal position is holding each switching valve in an offset position while the difference between An artificial respirator characterized in that a flow path for supplying inspiratory gas from an inspiratory gas pressure source to the mask is formed at the position. 2. Intake gas is supplied to the first and second switching valves from the intake gas pressure source via the pressure reducing valve, and when the first switching valve is in the offset position, the first switching valve
2. The artificial respirator according to claim 1, wherein the inspiratory gas is supplied to the mask via a switching valve. 3 Supplying intake gas from the intake gas pressure source to the first and second switching valves via the pressure reducing valve, and supplying intake gas to the mask via the second switching valve when the second switching valve is in the offset position. An artificial respirator according to claim 1, characterized in that: 4. Apply pilot pressure from the first switching valve in the normal position to the offset position of the second switching valve, and also apply pilot pressure to the normal position of the second switching valve and the second variable volume tank via the throttle. The pilot pressure is applied later than the pilot pressure in the direction of the offset position of the second switching valve, and the pilot pressure is applied in the direction of the offset position of the second switching valve from the first switching valve at the offset position and via the second check valve. simultaneously remove the pilot pressure in the direction of the normal position of the second switching valve and the second variable volume tank, and release the pilot pressure in the direction of the normal position of the first switching valve and the first reverse from the second switching valve in the offset position. Simultaneously apply the pilot pressure in the direction of the offset position of the first switching valve and the first variable volume tank via the stop valve, and increase the pilot pressure in the direction of the normal position of the first switching valve from the second switching valve in the normal position. is removed, and the pilot pressure in the direction of the offset position of the first switching valve and the first variable volume tank is released through the throttle later than the pilot pressure in the direction of the normal position of the first switching valve, and the first switching valve is removed. The valve and the second switching valve are each provided with a spring, and when the same pilot pressure is applied in the direction of the normal position and the direction of the offset position by the spring, each switching valve is held in the normal position, Each switching valve is held at the offset position while the difference in pilot pressure between the offset position direction and the normal position direction overcomes the force of the spring, and the first switching valve and the second switching valve are controlled from the intake gas pressure source. Inspiratory gas is supplied to the switching valve, and a flow path is formed at the position of the first or second switching valve to supply the inspiratory gas from the intake gas pressure source to the mask via the pressure reducing valve, so that the secondary pressure of the pressure reducing valve is An artificial respirator, characterized in that when the volume of the first and second variable volume tanks is large, the volumes of the first and second variable volume tanks are increased. 5 When the first switching valve is in the offset position,
5. The artificial respirator according to claim 4, wherein the inspiratory gas is supplied to the mask via the first switching valve.