JP2014180304A - Expiratory valve, and breath auxiliary device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control an expiratory valve accurately.SOLUTION: An expiratory valve 15 includes: a diaphragm 22 which opens/closes an outlet of an expiratory flow passage 13 guiding the expiration to the atmosphere; a back chamber 23 which is formed opposite to the expiration flow passage 13 in the diaphragm 22 and forms a space with the diaphragm 22; and a pump unit 25 which is fixed to a periphery of the back chamber 23, supplies and exhausts air in the back chamber 23 and adjusts an air pressure in the back chamber 23.

Description

  The present invention relates to an exhalation valve using a diaphragm and a breathing assistance device using the exhalation valve.

  In the medical field, a respiratory assistance device such as a ventilator is used. This breathing assistance device has a controlled ventilation system for patients without spontaneous breathing (general anesthesia, cardiopulmonary resuscitation, and severe patients), and positive pressure (positive pressure) in the respiratory tract according to the patient's spontaneous breathing Assisted Ventilation method to create Assistance, Partial Assist / Control method combining auxiliary ventilation and controlled ventilation, oscillate the gas supplied by the airway at a frequency of 5-40 Hz, 1-2 ml / kg Various systems such as a high frequency oscillation system that realizes a very low tidal volume are adopted.

  In any respiratory assistance device, a pump unit that creates a positive pressure in the airway and an exhalation valve that discharges exhalation to the atmosphere while keeping the airway at a positive pressure are required.

  The pump unit uses a relatively large device such as a blower that rotates a fan to convey gas and a cylinder pump that conveys gas by reciprocating a piston as a power source. For this reason, in the conventional respiratory assistance apparatus, the box-shaped housing | casing which accommodated the pump unit is installed and used by a user's side.

  Some exhalation valves have a simplified structure using a diaphragm (see, for example, Patent Document 1). The diaphragm is disposed so as to block the outlet of the pipe that guides exhalation, and opens the pipe by bending in a direction away from the outlet. A back chamber that is fed and exhausted by a pump unit is disposed on the opposite side of the pipe line in the diaphragm. That is, the diaphragm is arranged so as to partition the space in the pipe line and the space in the back chamber, and functions by the pressure difference between these spaces.

  Specifically, when the pressure in the pipeline is lower than the pressure in the back chamber, the diaphragm sticks to the outlet of the pipeline and seals it. On the other hand, when the pressure in the pipe line is higher than the pressure in the back chamber, the diaphragm is bent toward the back chamber side to open the pipe line, and exhaled air is released to the atmosphere. According to this exhalation valve, even if the patient coughs or sneezes, the diaphragm responds instantly and exhaled air is released into the atmosphere, so that the air pressure in the pipeline does not rise too much, and eventually It is possible to prevent the patient from being burdened.

JP 05-245204 A (see paragraph [0014] and FIG. 1)

  A pump unit installed beside the user has a path to the back chamber. For this reason, a certain amount of response time is required until the power from the pump unit acts on the back chamber. However, it is desired that the exhalation valve can be accurately controlled by shortening the response time in the medical field where human life is involved. Yes.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an exhalation valve that can be controlled with high accuracy and a breathing assistance device including the exhalation valve.

  The above-mentioned object is achieved by the following means based on the earnest research of the present inventors.

  That is, the means for achieving the above object includes a diaphragm that opens and closes an outlet of an exhalation flow path that guides exhalation to the atmosphere, and a back that is provided on the opposite side of the exhalation flow path in the diaphragm and forms a space together with the diaphragm. A chamber, a micropump that is provided around the back chamber, adjusts the air pressure in the back chamber by supplying and exhausting air to the back chamber, and a control unit that controls the operation of the micropump. It is a featured exhalation valve.

  In the above invention, the exhalation valve that achieves the above object includes an open force calculating means that calculates an open force acting on the diaphragm from the exhalation flow path side by the air pressure in the exhalation flow path in conjunction with a breathing action, A back chamber side barometer that measures the pressure in the back chamber and outputs the measurement result as a signal to the control unit, and the control unit uses the measurement result of the back chamber side barometer. The closing force acting on the diaphragm is calculated from the back chamber side based on the atmospheric pressure in the back chamber, and the micropump is controlled so that the closing force substantially coincides with the opening force. Is preferred.

  In the above invention, the exhalation valve that achieves the above object includes an exhalation measuring instrument that measures an exhalation flow and outputs the measurement result as a signal to the control unit, and the control unit measures the exhalation measuring instrument. If the result indicates exhalation exceeding a preset flow rate or flow rate, the micropump is not controlled so that the closing force substantially matches the opening force, but the closing force is weakened and the closing force is reduced. It is preferable that the micropump is controlled so that the force is less than the opening force.

  In the above invention, an exhalation valve that achieves the above object includes, as the micropump, an air supply micropump that supplies air to the back chamber and an exhaust micropump that exhausts the back chamber. Preferably it is a feature.

  In the above invention, the micropump for exhalation of the exhalation valve that achieves the above object includes an insufflation port for inhaling gas from outside the back chamber, and an inhalation port directly connected to the back chamber. An exhaust port for discharging the sucked gas into the back chamber, and the exhaust micropump is directly connected to the back chamber and directly sucks the gas from the back chamber; And an exhaust outlet for discharging the gas sucked from the exhaust inlet to the outside of the back chamber.

  In the above invention, the control unit of the exhalation valve that achieves the above object operates both the air supply micropump and the exhaust micropump simultaneously, and the air supply micropump and the exhaust micropump. It is preferable that the air pressure in the back chamber is controlled by stopping one of the operations.

  In the above invention, the micropump of the exhalation valve that achieves the above object has an inlet for sucking gas and an outlet for discharging the gas sucked from the inlet. One of the outlets is selectively connected to the back chamber, and the switching is performed so that the connection between the suction port and the discharge port with the back chamber is switched to selectively supply and exhaust air to the back chamber. It is preferable that the pump unit is configured together with the mechanism.

  In the above invention, the exhalation-valve switching mechanism that achieves the above-described object is characterized in that the micropump has an attitude in which the micropump exhausts the back chamber by connecting the suction port directly to the back chamber; It is preferable that the discharge port is directly connected to the back chamber and the micropump is switched between an air supply posture for supplying air to the back chamber.

  In the above invention, the means for achieving the above object comprises: an inspiratory flow path for introducing a gas to be exhaled from a supply source to a living body; an expiratory flow path for guiding the exhaled gas of the living organism to the atmosphere; and a gas in the expiratory flow path. An exhalation valve according to any one of the above-described inventions, wherein the exhalation valve according to any one of the above-mentioned inventions is released to the atmosphere to adjust the air pressure in the exhalation flow path.

  According to the present invention, it is possible to achieve an excellent effect that the exhalation valve can be accurately controlled.

It is the schematic which shows the structure of the respiratory assistance apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the example of control of an exhalation-valve, (A) shows the state which closed or opened the exit of the expiration flow path at the time of normal breathing, (B) is the exit of the expiration flow path at the time of the expiration by coughing or sneezing Indicates a state where is forcibly opened. (A) is sectional drawing which shows the structural example of the micropump used with a pump unit, (B) is a graph which shows the pressure-flow rate line of the micropump. It is a block diagram which shows the hardware constitutions of the control apparatus used with the pump unit. It is a block diagram which shows the function structure of the control apparatus used with the pump unit. It is the schematic which shows the structure of the respiratory assistance apparatus which concerns on 2nd Embodiment of this invention. It is the schematic which shows the example of control of a pump unit, (A) shows the state from which the attitude | position of a micro pump becomes an air supply attitude | position which supplies air with respect to a back chamber, (B) is the exhaust_gas | exhaustion with respect to a back chamber. The state which becomes the exhaust posture which performs is shown. It is a block diagram which shows the function structure of the control apparatus used with the pump unit. It is the schematic which shows the structure of the respiratory assistance apparatus which concerns on 3rd Embodiment of this invention. It is the schematic which shows the example of control of a pump unit, (A) shows the state in which a micropump supplies air with respect to a back chamber, (B) shows the state in which a micropump exhausts with respect to a back chamber. It is the schematic which shows the structure of the respiratory assistance apparatus which concerns on another embodiment.

  Hereinafter, examples of embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 illustrates the configuration of a medical respiratory assistance device 10 according to the first embodiment of the present invention. The breathing assistance device 10 includes a gas supply source 11 that serves as an exhalation, an intake flow channel 12 that guides the gas from the supply source 11 to the user, and a branch from the intake flow channel 12 to make the user's exhalation into the atmosphere. A leading exhalation flow path 13, a barometer 14 that measures the air pressure in the exhalation flow path 13, and a flow meter (expiratory flow meter) 17 that detects the flow of breathing air (flow rate, flow velocity, and flow direction) by the user; And an exhalation valve 15 that adjusts the air pressure in the exhalation flow path 13 by releasing the gas in the exhalation flow path 13 to the atmosphere, and a control unit 16 that controls the entire apparatus.

  The supply source 11 adjusts the flow rate of the gas supplied from the gas tank 18 which stored in the state which compressed gas, such as air and oxygen, the on-off valve 21 which opens and closes the flow of the gas from this gas tank 18, and the gas tank 18 A flow rate adjusting valve 19 and a flow meter 20 for measuring the flow rate of the gas adjusted by the flow rate adjusting valve 19 are provided. The on-off valve 21 and the flow rate adjusting valve 19 are controlled based on respective sensing data (detection / measurement results, sensing signals) of the barometer 14 and the flow meters 17 and 20. The type of the on-off valve 21 is not particularly limited, but an electric valve, an electromagnetic valve having a high response speed, or the like can be employed. The type of the flow rate adjusting valve 19 is not particularly limited, but a needle valve or the like can be adopted. The flow meter 20 outputs sensing data to the control unit 16.

  The inspiratory flow path 12 and the expiratory flow path 13 are each made of a resin bellows tube and integrally form one space. The atmospheric pressure in the inspiratory flow path 12 matches the atmospheric pressure in the expiratory flow path 13 in a steady state. An expiratory valve 15 is provided at the outlet of the expiratory flow path 13 branched from the inspiratory flow path 12. The barometer 14 outputs sensing data to the control unit 16. The flow meter 17 outputs sensing data to the control unit 16.

  The exhalation-valve 15 functions as a check valve that prevents the backflow of the atmosphere while releasing exhalation into the atmosphere. The exhalation valve 15 includes a diaphragm 22 that opens and closes an outlet of the exhalation flow path 13, a back chamber 23 that is provided on the opposite side of the exhalation flow path 13 in the diaphragm 22 and forms a space together with the diaphragm 22, and the back A barometer 24 that measures the atmospheric pressure in the chamber 23; and a pump unit 25 that is directly fixed around the back chamber 23 and that feeds and exhausts air to the back chamber 23 to adjust the atmospheric pressure in the back chamber 23. ing.

  The diaphragm 22 is a thin plate that is slightly larger than the outlet of the exhalation flow path 13 and is disposed so as to close the outlet. That is, the diaphragm 22 is disposed so as to partition the space in the exhalation flow path 13 and the space in the back chamber 23. The diaphragm 22 has an opening force F1 (= P1 × S1, S1; an opening area at the outlet of the expiratory flow path 13) that is acted on by the air pressure P1 in the expiratory flow path 13 during normal breathing, and in the back chamber 23. The closing force F2 (= P2 × S2, S2; area of the diaphragm 22) acting by the atmospheric pressure P2 is controlled so as to substantially match, and the outlet of the exhalation flow path 13 can be easily opened and closed ( (See FIG. 2A). For this reason, the diaphragm 22 opens in the exhalation flow path 13 by bending in a direction away from the exit, and discharges exhalation. Further, the diaphragm 22 is controlled so that the closing force F2 is weakened and the closing force F2 is less than the opening / closing force F1 during exhalation due to coughing or sneezing, and the diaphragm 22 is positively bent in a direction away from the outlet, and the expiration channel 13 Is forcibly released to release exhaled air (see FIG. 2B).

  The barometer 24 outputs sensing data to the control unit 16. The pump unit 25 includes an air supply micropump 27 that supplies air to the back chamber 23 and an exhaust micropump 28 that exhausts air to the back chamber 23. In the present embodiment, the case where the pump unit 25 is directly fixed around the back chamber 23 will be described as an example. However, the pump unit of the present invention only needs to be provided around the back chamber. As used herein, “around the back chamber” may have a distance by interposing some part with the back chamber. However, from the viewpoint of responsiveness, it is preferably fixed directly around the back chamber.

  The air feeding micropump 27 discharges the gas sucked from the air feeding inlet 29 directly connected to the back chamber 23 and the air feeding inlet 29 for sucking gas from the outside of the back chamber 23 to the back chamber 23. An air supply outlet 30 and the like. The air supply micropump 27 is controlled by the control unit 16 based on the sensing data of the barometers 14 and 24 and the flow meter 17.

  The exhaust micropump 28 is directly connected to the back chamber 23 and directly exhausts the gas from the back chamber 23 and discharges the gas sucked from the exhaust suction port 31 to the outside of the back chamber 23. And an exhaust outlet 32 for exhaust. The exhaust micro pump 28 is controlled by the control unit 16 based on the sensing data of the barometers 14 and 24 and the flow meter 17.

  The control unit 16 controls the pump unit 25 based on the sensing data of the barometers 14 and 24 and the flow meter 17. The control unit 16 controls the supply source 11 based on the sensing data of the barometer 14 and the flow meter 20. A detailed description of the control by the control unit 16 will be described later.

  The micropump 100 shown in FIG. 3A is employed for each of the air supply micropump 27 and the exhaust micropump 28. This micropump 100 is proposed in Patent Document WO2008 / 069266, and includes a primary blower chamber 101 and a secondary blower chamber 102 formed outside the primary blower chamber 101.

  The primary blower chamber 101 includes a piezoelectric element 103 serving as a vibration source, a diaphragm 104 to which the piezoelectric element 103 is fixed, and a vibration frame 105 that forms a space together with the diaphragm 104. The vibration frame 105 has an opening 106 that moves fluid inside and outside the primary blower chamber 101. The secondary blower chamber 102 has a suction port 107 on the diaphragm 104 side and a discharge port 108 so as to face the opening 106.

  In the micropump 100 described above, when the diaphragm 104 resonates by the piezoelectric element 103, the fluid moves between the primary blower chamber 101 and the secondary blower chamber 102, and the vibration frame 105 resonates due to the fluid resistance caused by the fluid. Due to the resonance between the diaphragm 104 and the vibration frame 105, the fluid is sucked from the suction port 107 and discharged from the discharge port 108.

  The micropump 100 is suitable for blower applications that transport gas, and can be transported without using a check valve. The micropump 100 has a box shape with an outer diameter of about 20 mm × 20 mm × 2 mm and is extremely small. However, when the input sine wave is set to 26 kHz at 15 Vpp (Volt peak to peak), the maximum is about 1 L / min (static pressure). Air at 0 Pa) and a maximum static pressure of about 2 kPa (flow rate 0 L / min) can be obtained.

  On the other hand, since the micropump 100 conveys the fluid by the vibration of the diaphragm 104 by the piezoelectric element 103, the volume of the fluid that can be conveyed is naturally limited, and this static pressure / flow rate characteristic is also shown in FIG. A straight line. That is, for example, when a static pressure of about 1 kPa is obtained, the flow rate is 0.5 L / min.

  Note that, when the Vpp of the input sine wave is changed to 10 or 20, the amplitude of the piezoelectric element 103 changes, so that the flow rate and pressure can be changed. That is, when Vpp of the input sine wave is changed smoothly, the flow rate and pressure can be changed smoothly. Alternatively, when the frequency of the input sine wave is changed, the flow rate and pressure can be changed. That is, when the frequency of the input sine wave is changed smoothly, the flow rate and pressure can be changed smoothly. However, the flow rate and pressure have upper limits depending on the ability of the piezoelectric element 103, the strength of the member, and the durability. Usually used at rated Vpp and frequency.

  Although a monomorph (unimorph) structure in which one piezoelectric element 103 is attached to the diaphragm 104 is introduced here, it is of course possible to adopt a bimorph structure in which two piezoelectric elements are attached to increase the vibration amount. . There are various other structures of the micropump 100 such as a structure suitable for liquid transport. Therefore, in the present invention, an optimum structure may be adopted according to the purpose. That is, the micropump 100 described here can convey gas without using a check valve, but instead of the micropump 100, a micropump having check valves at the suction port and the discharge port may be applied. good.

  As shown in FIG. 4, the control unit 16 includes a CPU 34, a first storage medium 35, a second storage medium 36, a third storage medium 37, an input device 38, and a display device 39 as hardware configurations. The input / output interface 40 and the bus 41 are provided.

  The CPU 34 is a so-called central processing unit, and implements various functions of the control unit 16 by executing various programs. The first storage medium 35 is a so-called RAM (Random Access Memory) and is used as a work area for the CPU 34. The second storage medium 36 is a so-called ROM (read only memory) and stores a basic OS executed by the CPU 34. The third storage medium 37 is composed of a hard disk device incorporating a magnetic disk, a disk device containing a CD, a DVD, or a BD, a non-volatile semiconductor flash memory device, and the like. Sensing data of the meters 14 and 24 and the flow meter 20 are stored.

  The input device 38 is an input key, a keyboard, or a mouse, and inputs various information. The display device 39 is a display and displays various operation states. The input / output interface 40 inputs and outputs sensing data of the barometers 14 and 24 and the flow meter 20, a power source (sine waveform) for operating the air supply micropump 27 and the exhaust micropump 28, and a control signal. Further, the input / output interface 40 acquires data such as a program from an external personal computer and outputs sensing data to the personal computer. The bus 41 is a wiring that performs communication by integrally connecting the CPU 34, the first storage medium 35, the second storage medium 36, the third storage medium 37, the input device 38, the display device 39, the input / output interface 40, and the like. .

  FIG. 5 shows a functional configuration obtained by the CPU 34 executing the control program stored in the control unit 16. The control unit 16 includes a sensing unit 43, a pump control unit 44, and a valve control unit 45 as functional configurations.

  The sensing unit 43 always acquires sensing data of the barometers 14 and 24 and the flow meter 17 and transmits the sensing data to the pump control unit 44. Further, the sensing unit 43 always acquires sensing data of the barometer 14 and the flow meters 17 and 20 and transmits the sensing data to the valve control unit 45.

  The pump control unit 44 refers to the sensing data of the sensing unit 43, and approximates the Vpp and frequency of the input sine wave to the air supply micropump 27 and the exhaust micropump 28 to the target flow value and pressure value. To control. Specifically, the pump control unit 44 uses the detection result of the barometer 14 to release force F1 (= P1 × S1,...) Acting on the diaphragm 22 from the side of the expiration flow path 13 by the pressure P1 in the expiration flow path 13. S1; an opening area at the outlet of the exhalation flow path 13), and a closing force F <b> 2 acting on the diaphragm 22 from the back chamber 23 side by the atmospheric pressure P <b> 2 in the back chamber 23 using the detection result by the barometer 24. = P2 × S2, S2; area of diaphragm 22). Therefore, it can be said that the pump control unit 44 functions as an opening force calculation unit that calculates the opening force F1 in conjunction with the breathing motion.

  And the pump control part 44 controls the pump unit 25 so that the closing force F2 substantially corresponds to the opening force F1.

  However, when the detection result of the flow meter 17 indicates expiration (exhalation due to coughing or sneezing) exceeding the preset flow rate / flow velocity (threshold), the pump control unit 44 changes the closing force F2 to the opening force F1. The pump unit 25 is not controlled so as to be substantially coincident, but the closing force F2 is weakened and the closing force F2 is controlled to be less than the opening force F1. Note that the threshold value may be set as appropriate in consideration of the fact that the flow rate of exhaled air due to coughing or sneezing is larger as the order differs than the flow rate of exhaled air due to normal breathing.

  The valve control unit 45 refers to the sensing data of the sensing unit 43 and controls the control signals to the on-off valve 21 and the flow rate adjustment valve 19 so as to approach the target flow rate value.

  Next, a control example of the respiratory assistance device 10 will be described.

  When the user exhales with normal breathing, the pressure in the exhalation flow path 13 is increased. When the pressure inside the exhalation flow path 13 is increased, it is sensed by the barometer 14. Sensing data is output to the control unit 16. The control unit 16 controls the supply source 11 and the pump unit 25 based on the sensing data. That is, the on-off valve 21 is closed and the supply of gas from the gas tank 18 is stopped. Further, in accordance with the operation of the on-off valve 21, the air supply micropump 27 and the exhaust micropump 28 are operated to supply and exhaust air to the back chamber 23, thereby adjusting the atmospheric pressure in the back chamber 23 toward the target value. To do. This keeps the closing force F1 substantially equal to the opening force F2. The exhaled air is released from the outlet of the expiratory flow path 13 by opening the expiratory flow path 13 by bending the diaphragm 22 away from the outlet.

  Subsequently, when the user inhales, the inside of the exhalation flow path 13 is depressurized. When the inside of the exhalation flow path 13 is depressurized, it is sensed by the barometer 14. Sensing data is output to the control unit 16. The control unit 16 controls the supply source 11 and the pump unit 25 based on the sensing data. That is, the gas is supplied from the gas tank 18 by opening the on-off valve 21, and the amount of gas supplied from the gas tank 18 by the flow rate adjusting valve 19 is adjusted toward the target value. Further, in accordance with the operation of the on-off valve 21 and the flow rate adjusting valve 19, the air supply micropump 27 and the exhaust micropump 28 are operated to supply and exhaust the back chamber 23, and the atmospheric pressure in the back chamber 23 is set as a target. Adjust towards the value. This keeps the closing force F1 substantially equal to the opening force F2. The opening of the exhalation flow path 13 is sealed by a diaphragm 22.

  Subsequently, when the user exhales due to coughing or sneezing during inspiration, the exhalation is sensed by the flow meter 17. Further, the atmospheric pressure in the exhalation flow path 13 and the atmospheric pressure in the back chamber 23 are sensed by the barometers 14 and 24. Each sensing data is output to the control unit 16. The control unit 16 controls the pump unit 25 and the supply source 11 based on the sensing data. That is, the exhaust micropump 28 is operated to exhaust the back chamber 23 to reduce the pressure in the back chamber 23 toward the target value. As a result, the closing force F2 is weakened and the closing force F2 is less than the opening force F1, and the diaphragm 22 bends away from the outlet to forcibly open the exhalation flow path 13. Exhaled air due to coughing or sneezing is discharged from the outlet of the exhalation flow path 13. Further, in accordance with the operation of the exhaust micropump 28, the on-off valve 21 is closed, and the supply of gas from the gas tank 18 is stopped.

  According to the respiratory assistance device 10 described above, since the pump unit 25 is fixed around the back chamber 23, no response time is required until the power from the pump unit 25 acts on the back chamber 23, and the exhalation valve Can be accurately controlled. As a result, there is no problem in medical practice related to human life. Since the back chamber 23 and the pump unit 25 are integrated, even if the back chamber 23 moves in conjunction with the movement of the user's body, the back chamber 23 and the pump unit 25 move together. The connection between the back chamber 23 and the pump unit 25 is not interrupted. Therefore, the stability of the breathing assistance operation is increased and the user can easily move the body.

  Since the pump unit 25 includes the air supply micropump 27 and the exhaust micropump 28, the supply / exhaust switching control for the back chamber 23 can be performed with high accuracy. Since each micropump 25 is small, even if a plurality of micropumps 25 are arranged, the micropump 25 can be made smaller and lighter than a conventional pump unit such as a blower. Furthermore, since the miniaturized pump unit 25 is directly fixed to the back chamber 23, the respiratory assistance device 10 can be configured extremely compactly.

  FIG. 6 illustrates the configuration of a medical respiratory assistance device 50 according to the second embodiment. Since the first embodiment and the second embodiment have many parts that are the same or similar, explanations thereof will be omitted, and here, differences from the first embodiment will be mainly described. Regarding the third embodiment and another embodiment to be described later, the description common to the other embodiments is omitted, and the difference from the other embodiments will be mainly described.

  The respiratory assistance device 50 includes a pump unit 51 that employs one micropump 52 instead of the pump unit 25 that employs the two micropumps 27 and 28. The pump unit 51 includes a micropump 52 that selectively supplies and exhausts air to the back chamber 23, and a switching mechanism 53 that selectively changes the attitude of the micropump 52 to selectively supply and exhaust air to the back chamber 23. Yes.

  The micropump 52 includes a suction port 54 for sucking gas, a discharge port 55 for discharging gas sucked from the suction port 54, and the like. As the micro pump 52, a micro pump 100 shown in FIG.

  The micro pump 52 is switched in posture by the switching mechanism 53 to switch the connection relationship between the suction port 54 and the discharge port 55 with the back chamber 23, and one of the suction port 54 and the discharge port 55 is selectively connected to the back chamber. 23. Specifically, the attitude of the micropump 52 is switched between an air supply attitude shown in FIG. 7A and an exhaust attitude shown in FIG. 7B. In the air supply posture, the discharge port 55 is directly connected to the back chamber 23, and the micropump 52 supplies air to the back chamber 23. In the exhaust posture, the suction port 54 is directly connected to the back chamber 23, and the micropump 52 exhausts the back chamber 23.

  FIG. 8 shows a functional configuration obtained when the control program stored in the control unit 16 is executed by the CPU 34. The control unit 16 includes a switching control unit 57 and the like as a functional configuration. The sensing unit 43 always acquires the sensing data of the flow meter 17 and transmits it to the switching control unit 57. The switching control unit 57 refers to the sensing data of the sensing unit 43 and controls the control signal to the switching mechanism 53 so as to be the target posture of the micropump 52.

  Next, a control example of the respiratory assistance device 50 will be described.

  When the user exhales, the exhalation is sensed by the flow meter 17. Sensing data is output to the control unit 16. The control unit 16 controls the pump unit 51 and the like based on the sensing data. That is, the switching mechanism 53 is operated to appropriately switch the attitude of the micropump 52 and the micropump 52 is operated to supply and exhaust air to the back chamber 23 to adjust the inside of the back chamber 23 toward the target value.

  Subsequently, when the user inhales, the inhalation is sensed by the flow meter 17. Sensing data is output to the control unit 16. The control unit 16 controls the pump unit 51 and the like based on the sensing data. That is, the switching mechanism 53 is operated to appropriately switch the attitude of the micropump 52 and the micropump 52 is operated to supply and exhaust air to the back chamber 23 to adjust the inside of the back chamber 23 toward the target value.

  According to the respiratory assistance device 50 described above, air supply / exhaust to the back chamber 23 can be performed only by providing one micropump 52. Thereby, compared with the respiratory assistance apparatus 10 of 1st Embodiment, it can comprise still smaller and lightweight.

  FIG. 9 illustrates the configuration of a medical respiratory assistance device 60 according to the third embodiment. The respiratory assistance device 60 includes a pump unit 61 that switches the connection relationship without changing the posture of the micropump 62 instead of the pump unit 51 that switches the connection relationship by changing the posture of the micropump 52. The pump unit 61 includes a micropump 62 that selectively supplies and discharges air to the back chamber 23, a suction pipe 63 to which the suction port of the micropump 62 is connected, and a discharge pipe 64 to which the discharge port of the micropump is connected. And a switching valve 65 for switching the connection relationship of the suction pipe 63 and the discharge pipe 64 to the back chamber 23.

  The micropump 62 includes a suction port and a discharge port (both of which are not shown). As the micropump 62, a micropump 100 shown in FIG.

  In the micropump 62, the connection relationship between the suction port and the discharge port to the back chamber 23 is switched by the switching valve 65, and one of the suction port and the discharge port is selectively connected to the back chamber 23. Specifically, the state is switched between a state where the air supply shown in FIG. 10A is performed and a state where the exhaust shown in FIG. 10B is performed. In the state where air is supplied, the discharge pipe 64 is directly connected to the back chamber 23, and the micropump 62 supplies air to the back chamber 23. In the exhaust state, the suction pipe 63 is directly connected to the back chamber 23, and the micropump 62 exhausts the back chamber 23.

  Note that the pump unit and the respiratory assistance device of the present invention are not limited to the above-described embodiments, and it is needless to say that various modifications can be made without departing from the gist of the present invention. In addition, the configuration requirements of the above-described embodiment may be applied to other embodiments to the extent possible.

  That is, in the respiratory assistance device 10 according to the first embodiment, one air supply micropump 27 and one exhaust micropump 28 are provided, but a plurality of each may be provided. In this case, they may be connected in series or in parallel, or may be connected in a lattice shape (series and parallel) having a relationship between rows and columns. In these cases, even if an individual micropump breaks down, it can be compensated by other micropumps, so that safety can be improved.

  In the respiratory assistance device 10 according to the first embodiment, the control unit 16 operates one of the air supply micropump 27 and the exhaust micropump 28, but is not limited to this control mode. . That is, the control unit 16 operates both the air supply micropump 27 and the exhaust micropump 28 and stops the operation of one of the air supply micropump 27 and the exhaust micropump 28. The atmospheric pressure in the chamber 23 may be controlled. Thereby, the time lag due to the delay of the rising can be eliminated, and the exhalation valve 15 can be controlled with higher accuracy.

  Further, in the respiratory assistance device 50 according to the second embodiment, the switching mechanism 53 switches the posture of the micropump 52 so as to switch the supply / exhaust to the back chamber 23, but the posture of the micropump 52 remains fixed. Thus, the air supply / exhaust to the back chamber 23 may be switched by switching the path of the micro pump 52 by an electromagnetic valve or the like.

  Moreover, in each said embodiment, although the case of the opening force calculation means which calculates opening force F1 based on the measurement result of the barometer 14 was demonstrated to the example, the opening force calculation means in this invention is not limited to this. The opening force F <b> 1 may be calculated based on a signal (a signal for controlling the amount of gas supplied from the gas tank 18) of the valve control unit 45 that controls the operation of the flow rate adjusting valve 19.

  Next, a medical respiratory assistance device 70 according to another embodiment will be described. FIG. 11 illustrates the configuration of the respiratory assistance device 70. The respiratory assistance device 70 includes a pump unit 71 that employs a pump other than the micropump instead of the pump unit 25 that employs the micropumps 27 and 28.

  The pump unit 71 includes an air supply pump 72 that supplies air to the back chamber 23 and an exhaust pump 73 that exhausts the back chamber 23. The type of the air supply pump 72 is not particularly limited, but a rotary pump provided with an impeller is used. The type of the exhaust pump 73 is not particularly limited, but the type is not particularly limited, but a rotary pump equipped with an impeller can be employed. Further, a chamber 73 a that can be evacuated may be provided between the exhaust pump 73 and the back chamber 23. By providing the chamber 73a that can be evacuated, the back chamber 23 can be exhausted instantaneously, and the responsiveness can be improved. The basic control of the pump unit 71 is the same as the control of the pump unit 25.

  The respiratory assistance device of the present invention can be used for the purpose of assisting various organisms.

10, 50, 60 Respiration assist device 11 Supply source 12 Inspiratory flow path 13 Expiratory flow path 14 Barometer 15 Expiratory valve 16 Control unit 17 Flow meter (expiratory meter)
22 Diaphragm 23 Back chamber 24 Barometer (Back chamber side barometer)
25, 51, 61 Pump unit 27 Micro pump for air supply 28 Micro pump for exhaust air 29 Suction port for air supply 30 Suction port for air supply 31 Suction port for exhaust 32 Ejection port for exhaust 44 Pump control unit (opening force calculation means)
52, 62, 100 Micro pump 53 Switching mechanism 54, 107 Suction port 55, 108 Discharge port

Claims (9)

A diaphragm that opens and closes the exit of the exhalation flow path that guides exhalation to the atmosphere;
A back chamber which is provided on the opposite side of the exhalation flow path in the diaphragm and forms a space together with the diaphragm;
A micropump provided around the back chamber, for adjusting the atmospheric pressure in the back chamber by supplying and exhausting the back chamber;
A control unit for controlling the operation of the micropump,
Exhalation valve. An opening force calculating means for calculating an opening force acting on the diaphragm from the side of the exhalation flow path by an air pressure in the exhalation flow path in conjunction with a breathing action;
A back chamber side barometer that measures the atmospheric pressure in the back chamber and outputs the measurement result as a signal to the control unit,
The control unit is
Using the measurement result of the back chamber side barometer, the closing force acting on the diaphragm from the back chamber side is calculated from the pressure in the back chamber, and the closing force substantially matches the opening force. The micro pump is controlled by
The exhalation-valve according to claim 1. Comprising an exhalation meter that measures the flow of exhalation and outputs the measurement result as a signal to the control unit;
The control unit is
When the measurement result of the exhalation meter indicates exhalation exceeding a preset flow rate or flow velocity, the micropump is not controlled so that the closing force substantially coincides with the opening force. The micropump is controlled so that the closing force is less than the opening force by weakening the force,
The exhalation-valve according to claim 2. As the micropump,
An air supply micropump for supplying air to the back chamber;
An exhaust micropump for exhausting the back chamber,
The exhalation-valve in any one of Claims 1-3. The air supply micropump is an air supply intake port for sucking gas from outside the back chamber, and a gas supply port that is directly connected to the back chamber and discharges the gas sucked from the air supply intake port into the back chamber. A gas outlet,
The exhaust micropump is directly connected to the back chamber and exhausts the gas directly from the back chamber. The exhaust micropump discharges the gas sucked from the exhaust suction outside the back chamber. And an outlet.
The exhalation-valve according to claim 4. The control unit operates both the air supply micropump and the exhaust micropump at the same time, and stops the operation of one of the air supply micropump and the exhaust micropump. Controlling the atmospheric pressure in the chamber,
The exhalation-valve according to claim 4 or 5. The micropump is
A suction port for sucking gas and a discharge port for discharging the gas sucked from the suction port, and one of the suction port and the discharge port is selectively connected to the back chamber. ,
The pump unit is configured together with a switching mechanism that selectively connects and discharges air to and from the back chamber by switching the connection relationship between the suction port and the discharge port with the back chamber.
The exhalation-valve in any one of Claims 1-3. The switching mechanism is configured such that the micro pump has an attitude in which the suction port is directly connected to the back chamber and the micro pump exhausts air from the back chamber, and the discharge port is directly connected to the back chamber. The micropump is switched between an air supply posture for supplying air to the back chamber,
The exhalation-valve according to claim 7. An intake passage that guides the gas to be inhaled from the supply source to the organism,
An exhalation flow path for guiding exhalation of the organism to the atmosphere;
The exhalation valve according to any one of claims 1 to 8, wherein the exhalation valve according to any one of claims 1 to 8, which adjusts the atmospheric pressure in the exhalation flow path by releasing the gas in the exhalation flow path to the atmosphere,
Respiratory device.

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