JP6536669B2 - Suction device - Google Patents

Description

  The present invention relates to a suction device for suctioning saliva or the like of a patient.

  For example, a medical suction device for continuously suctioning secretions such as saliva accumulated in the upper part of the tracheal tube cuff or in the oral cavity has an electric pump for generating suction pressure and a drainage container for collecting drainage. ing. As such a suction device, for example, an electric low pressure continuous suction device provided with an electric pump disclosed in Japanese Patent Laid-Open No. 2000-60962 (Patent Document 1) can be mentioned.

JP 2000-60962 A

  The electric pump used in the conventional suction device basically changes the volume of the pump chamber periodically by a drive source (motor, electromagnet, piezoelectric body, etc.), and sends air in one direction only by a check valve. Is configured as. Therefore, air flows in the suction direction but does not flow in the opposite direction.

  Therefore, if the suction tube tip is in a state of being adsorbed to the tracheal mucous membrane or oral mucous membrane at the time of suction, the inside of the drainage container is maintained at negative pressure even after stopping the driving of the pump. There is a problem that the adsorption state can not be released and there is a risk of mucosal damage.

  Although Patent Document 1 states that it is necessary to provide pressure detection means for appropriately maintaining suction pressure, even if pressure detection means are provided, air flows in the direction opposite to the suction direction. If this is not the case, it is not possible to release the suction state of such a suction tube tip.

  An object of the present invention is to provide a suction device capable of releasing an adsorption state of a tip of a suction pipe by stopping driving of a pump.

[1] An exhaust flow path having an exhaust port and an intake port, and a blower unit including a piezoelectric blower provided in the middle of the exhaust flow path,
And a drainage container including a reservoir having an inlet and a negative pressure port;
A suction device, wherein the intake port and the negative pressure port are in communication.

[2] The intake port and the negative pressure port are in communication via a connection flow path,
The suction device according to [1], wherein the connection flow channel is separated into a plurality of flow channels by at least one flow velocity attenuation unit.

  [3] The device according to [2], wherein the shortest path distance from the negative pressure port to the intake port via the connection flow path is longer than the linear distance between the negative pressure port and the intake port. Suction device.

  [4] The suction device according to any one of [1] to [3], wherein the negative pressure port has a hydrophobic filter.

  [5] The distance of the shortest path from the intake port to the exhaust port via the exhaust flow path of the blower unit is longer than the linear distance between the intake port and the exhaust port [1] The suction device according to any one of [4].

  [6] The suction device according to any one of [1] to [5], wherein the exhaust port has a connector.

[7] The blower unit has a suction port communicating with the inflow port of the drainage container,
The blower unit and the drainage container are mounted such that the centers of the suction port of the blower unit and the inlet of the drainage container coincide with each other.
In the mounting portion between the blower unit and the drainage container, a first annular portion centering on the centers of the inflow port and the suction port, and a second annular portion located concentrically with the first annular portion. And an annular part of the
The first annular portion is larger in diameter than the suction port and the inlet, and the second annular portion is larger in diameter than the first annular portion.
The suction device according to any one of [1] to [6], wherein the negative pressure port and the intake port are located outside the first annular portion and inside the second annular portion.

  [8] The suction device according to any one of [1] to [7], wherein the blower unit and the drainage container are removable.

[9] It also has a circuit unit,
The suction device according to any one of [1] to [8], wherein the circuit unit includes a power supply and a control unit that controls driving of the piezoelectric blower.

  [10] The suction device according to [9], wherein the control unit can intermittently drive the piezoelectric blower.

  [11] The suction device according to [9] or [10], wherein the circuit unit is removable.

  According to the present invention, it is possible to provide a suction device capable of releasing the suction state of the tip of the suction pipe by stopping the driving of the pump.

FIG. 2 is a block diagram schematically showing the configuration of the main part of the suction device of the first embodiment. FIG. 1 is a block diagram schematically showing an entire configuration of an example of a suction apparatus of Embodiment 1. FIG. 1 is a perspective view showing an example of the configuration of a suction device of Embodiment 1. FIG. 1 is a partially exploded perspective view showing the configuration of an example of a suction device of Embodiment 1. FIG. FIG. 2 is a partial exploded perspective cross-sectional view showing the configuration of an example of the suction device of the first embodiment. FIG. 1 is a cross-sectional view showing an example of the configuration of a suction device of Embodiment 1. It is sectional drawing in the C-C 'cross section of FIG. 6 which shows the structure of the connection flow path in an example of the suction device of Embodiment 1. FIG. It is sectional drawing in the B-B 'cross section of FIG. 6 which shows the structure of the exhaust flow path in an example of the suction device of Embodiment 1. FIG. (A) is a top view of the drainage container 11 in an example of the suction device of Embodiment 1. FIG. (B) is a bottom view of the blower unit 12 in an example of the suction device of Embodiment 1. FIG. FIG. 2 is a cross-sectional view showing the configuration of a piezoelectric blower used in the suction device of Embodiment 1. (A) is a schematic diagram which shows an example of a cuffed tracheal tube provided with the suction device of Embodiment 1. FIG. (B) is a schematic diagram which expands and shows the front-end | tip part of the cuffed tracheal tube shown to (a). (C) is a sectional view in the A-A 'section of (b). It is a schematic diagram which shows a mode that the tracheal tube was inserted in the trachea from the oral cavity. FIG. 7 is a schematic view showing the entire configuration of a modified example of the suction device of Embodiment 1.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals represent the same or corresponding parts. In addition, dimensional relationships such as length, width, thickness, and depth are appropriately changed for the sake of clarity and simplification of the drawings, and do not represent actual dimensional relationships. It is needless to say that the embodiment is an exemplification, and partial replacement or combination of the configurations shown in different forms is possible.

  The suction device of the present embodiment is, for example, a suction device for continuously suctioning secretions such as saliva accumulated in the upper part of the tracheal tube cuff or in the oral cavity, and includes a blower unit 12 for generating suction pressure, and drainage. And a drainage container 11 for storing (aspirated secretion etc.). First, before describing details of the suction device, the usage of the suction device of the present embodiment will be described.

  FIG. 12 is a schematic view showing the tracheal tube 8 inserted from the oral cavity 94 into the trachea 91. As shown in FIG. When the airway is secured by tracheal intubation when using a ventilator, a tracheal tube (endotracheal tube, intubation tube) 8 is inserted from the oral cavity 94 of the subject into the trachea 91. At this time, since the epiglottis 93 is always in an open state, secretions such as saliva flow into the trachea 91 from the gap between the inserted tracheal tube 8 and the inner wall 91a of the trachea 91, and the subject Ventilator-associated pneumonia (VAP) may develop.

  In order to prevent the inflow of such secretions, a cuff 2 is provided at a predetermined position on the outer periphery of the tracheal tube 8. The cuff 2 can be inflated by the supply of air from outside the body via an air supply pipe (not shown). By inflating the cuff 2, the outer peripheral surface of the cuff 2 contacts the inner wall 91a of the trachea 91, and the gap between the tracheal tube 8 and the inner wall 91a of the trachea 91 is closed. By using such a cuffed tracheal tube, it is possible to prevent the inflow of secretions and the like to the trachea 91 by the cuff 2 while securing the airway by the tracheal tube 8.

  However, the secretion accumulated in the upper part (oral cavity 94 side) of the cuff 2 leaks little by little to the lower airway from the gap between the inner wall 91a of the trachea 91 and the cuff 2 with time. Therefore, in order to prevent ventilator-associated pneumonia (VAP) more completely, it is said that continuous aspiration and removal of secretions accumulated in the upper part of the cuff 2 and in the oral cavity 94 is effective. ing.

  In order to facilitate the suction of such secretions, a cuffed tracheal tube having a hole 22c for suctioning the secretion near the top of the cuff 2 of the tracheal tube 8 is commercially available (See Figure 11).

  In the cuffed tracheal tube shown in FIG. 11, a flow passage 22a formed parallel to the main flow passage 8a is provided in the wall portion constituting the main flow passage 8a of the tracheal tube 8 (FIG. 11 (b) and (C)). One of the flow paths 22a communicates with a hole 22c opened to the outside of the tracheal tube 8 in the vicinity of the cuff 2 on the upper side (opposite to the tip) of the cuff 2. The other end of the flow path 22a communicates with the inside of the connection tube 22b through a hole 22d opened to the outside of the tracheal tube 8 at a portion which is not inserted into the oral cavity 94 of the patient. A connector 23a is provided at the tip of the connection tube 22b.

  The suction device 1 of the present embodiment is used in a state of being connected to such a connector 23 a via the connection tube 21. The other end of the connection tube 21 is connected to, for example, the suction port 124 of the suction device 1.

  The application of the suction device 1 of the present embodiment is not limited to such a tracheal intubation, and can be applied to various uses. For example, the present invention can be applied to a patient who needs aspiration and removal of secretions such as saliva, such as a patient with ALS (muscle contractile sclerosis).

  Hereinafter, the configuration of the suction device 1 of the present embodiment will be described with reference to FIG. The suction device 1 of the present embodiment includes at least a blower unit 12 and a drainage container 11.

  The blower unit 12 includes an exhaust flow path 123 having an exhaust port 122 and an intake port 121, and a piezoelectric blower 120 provided in the middle of the exhaust flow path 123. The drainage container 11 also includes a reservoir 113 having an inlet 111 and a negative pressure port 112. The intake port 121 and the negative pressure port 112 communicate with each other. Details of these will be described later.

  Next, the whole structure of an example of the suction device of this embodiment is shown in FIGS. The suction device 1 shown in FIGS. 2 to 6 is roughly divided into three units, and includes the above-described blower unit 12 and the drainage container 11, and further includes a circuit unit 13.

(Blower unit 12)
The blower unit 12 includes an exhaust flow path 123 having an exhaust port 122 and an intake port 121, and a piezoelectric blower 120 provided in the middle of the exhaust flow path 123. These are accommodated in a housing as shown in FIGS. 3 and 4 and the like.

  The piezoelectric blower 120 is a device that generates a suction force from the IN side to the OUT side in FIG. The piezoelectric blower 120 is characterized in that when the drive is stopped, air can flow in the direction opposite to the suction direction. Hereinafter, this feature will be described with reference to FIG.

  Referring to FIG. 10, in the piezoelectric blower 120, for example, a piezoelectric element 100 made of lead zirconate titanate (PZT) ceramic is attached to a metal diaphragm 101. In the diaphragm 101, a metal plate 102b provided with a discharge hole 102a at a central portion is bonded to sandwich the spacer 102c so as to form a pump chamber 102.

  When the piezoelectric element 100 is caused to resonate by applying a voltage, the diaphragm 101 is bent and vibrates, and a volume change occurs in the pump chamber 102. As a result, high speed flow of air is generated intermittently in the discharge holes 102a. At this time, the pressure in the vicinity of the discharge hole 102a is reduced, so the air in the suction passage 103 is sucked in the direction of the discharge hole 102a, and as a result, the air is discharged from the nozzle 104. Thus, the piezoelectric blower 120 acts as an air pump that sucks in air from the lower side and discharges it to the upper side, as shown by the arrow in FIG.

  Here, the piezoelectric blower 120 does not have a non-return structure, and as shown in FIG. 10, the suction side (lower side in the figure) and the discharge side (upper side in the figure) communicate. Therefore, when the voltage (power) supply is stopped and the bending vibration of the piezoelectric element 100 is stopped, air can also flow in the direction opposite to the suction direction shown by the arrow in FIG.

  Therefore, according to the suction apparatus of the present embodiment, the exhaust port 122 is immediately used even when the suction pipe tip is in a state of being adsorbed to the tracheal mucous membrane or the oral mucous membrane at the time of suction by utilizing such features of the piezoelectric blower 120. More air flows in, the negative pressure state in the drainage container 11 is canceled, and the suction state of the tip of the suction pipe can be released. Since there is a risk of mucosal damage if the adsorption state lasts for a long time, the suction device of the present embodiment is a device with higher safety than the prior art.

  In addition, for example, since the suction device described in Patent Document 1 sucks at a low pressure, the suction pipe may be clogged when a device with high viscosity is sucked. In that case, the aspiration tube has to be removed, which takes time and effort. In addition, the suction power of the pump can be made variable, and the suction power can be increased only when clogging occurs, but a pump with high performance is required, which leads to an increase in size and cost of the apparatus. Furthermore, since these high-performance pumps have high suction power, it is necessary to use pressure control means (pressure sensor, pressure reducing valve, etc.) in order to control at low pressure normally, which makes the equipment complicated and expensive. It is costly and takes time and effort to maintain.

  Therefore, the effect of the present embodiment is that, particularly when the suction device of the present embodiment performs suction at a low pressure, the suction state of the tip of the suction tube can be obtained without increasing the cost of the apparatus as described above. It is useful in that it can be released.

  With reference to FIGS. 3-5, it is preferable that the exhaust port 122 of the blower unit 12 be provided with a connector. For example, if a suction tube is clogged due to suction of a highly viscous secretion, if there is a connector, easily connect a tube from a vacuum source that generates a negative pressure higher than that of the piezoelectric blower 120. It is possible to easily perform an operation to temporarily increase the suction force and eliminate clogging of the suction pipe.

  The distance of the shortest path from the intake port 121 to the exhaust port 122 via the exhaust flow path 123 of the blower unit 12 is preferably longer than the linear distance between the intake port 121 and the exhaust port 122. Specifically, for example, it is preferable that the exhaust flow path 123 is a flow path detoured from the nozzle 104 of the piezoelectric blower 120 to the exhaust port 122 as shown in FIG. 8 in a plan view. As a result, the vibration noise generated by the vibration of the piezoelectric blower 120 can be made less likely to leak to the outside, and the quietness of the suction device can be improved.

  In the suction device 1 shown in FIGS. 2 to 6, the blower unit 12 has a suction port 124 communicating with the inflow port 111 of the drainage container 11. The aspirated secretions and the like (drainage) are sucked from the suction port 124 through a suction pipe or the like, and are sent into the storage chamber 113 of the drainage container 11 through the inlet 111.

  The suction port 124 is designed to mount the blower unit 12 on the entire upper surface of the drainage container 11, and when the inlet 111 is provided on the upper surface of the drainage container 11, the suction pipe or the like is connected to the inlet 111 However, the blower unit 12 need not necessarily have the suction port 124 otherwise. For example, as a modification of the present embodiment, as shown in FIG. 13, the blower unit 12 (and the circuit unit 13) is not provided on the entire upper surface of the drainage container 11, and the exposed portion of the upper surface of the drainage container 11 is An inlet 111 and a suction port 124 in direct communication with the inlet 111 may be provided.

(Drainage container 11)
The drainage container 11 has a storage chamber 113, and drainage (a suctioned secretion or the like) is stored in the storage chamber 113. The material, shape, and the like of the drainage container 11 are not particularly limited. However, when the inside of the storage chamber 113 becomes negative pressure by the drive of the piezoelectric blower 120, gas can communicate between the suction port and the drainage port The strength is required to maintain the negative pressure to maintain the state.

  The positions of the inflow port 111 and the negative pressure port 112 are not particularly limited as long as they are other than the bottom of the drainage container 11, but it is preferable that the positions be higher than the liquid level when the drainage is accumulated in the storage chamber 113. More preferably, the top plate of the drainage container 11 is provided with the inlet 111 and the negative pressure port 112.

  The negative pressure port 112 of the drainage container 11 is in communication with the intake port 121 of the blower unit 12 via the connection channel 114 (FIG. 2, FIG. 5, FIG. 6). As a result, the negative pressure generated in the blower unit 12 passes through the negative pressure port 112 to make the inside of the drainage container 11 negative pressure.

  As shown in FIG. 5, the connection flow channel 114 is formed on the lower side (to the storage chamber 113 side) of the top plate 114 a (see FIG. 9A) of the drainage container 11. Air in the storage chamber 113 is sucked from the negative pressure port 112 and flows into the connection port 115 through the connection flow path 114.

  In the suction device 1 shown in FIGS. 2 to 6, the blower unit 12 has the suction port 124 in communication with the inflow port 111 of the drainage container 11 as described above. The blower unit 12 and the drainage container 11 are mounted such that the centers of the suction port 124 of the blower unit 12 and the inflow port 111 of the drainage container 11 coincide with each other.

  In addition, the mounting portion 125 between the blower unit 12 and the drainage container 11 is concentric with the first ring-shaped portion 125a centering on the centers of the inflow port 111 and the suction port 124 and the first ring-shaped portion 125a. A second annular portion 125b is provided. The first annular portion 125a and the second annular portion 125b are, for example, rubber O-rings or the like. The first annular portion 125a is larger in diameter than the suction port 124 and the inlet 111, and the second annular portion 125b is larger in diameter than the first annular portion 125a. In addition, the negative pressure port 112 and the intake port 121 are located outside the first annular portion 125a and inside the second annular portion 125b.

  It should be noted that one of the blower unit 12 and the drainage container 11 has a bolt-like portion and the other has a nut-like portion, so that both can be screwed together and can be easily separated. Is also possible.

  The configuration of the mounting portion 125 as described above makes it possible to easily mount the blower unit 12 and the drainage container 11 by screwing without requiring a special lock mechanism. Further, it is not necessary to exactly align the negative pressure port 112 and the intake port 121 at the time of screwing, etc., and even if a slight displacement occurs, both can be reliably communicated.

  In addition, with the configuration of the mounting portion 125 as described above, it is possible to secure a path from the suction port 124 to the inflow port 111 and a plurality of flow paths of the connection flow path 114 respectively.

  The connection channel 114 is preferably separated into a plurality of channels by at least one flow rate attenuator.

  The flow velocity attenuation portion is a portion where the flow velocity of air sucked from the negative pressure port 112 to the intake port 121 (connection port 115) is slower than the other portion of the connection flow path 114. The flow rate damping portion is, for example, a portion where the pressure loss is larger than the other portions of the connection flow channel 114. Specific examples of the flow velocity attenuation portion include a portion where the flow passage cross-sectional area is smaller than the other portions of the connection flow passage 114, a portion where the flow passage is bent, and the like.

  Specifically, referring to FIG. 7, connection channel 114 is partitioned by annular partition 126 concentric with mounting portion 125 (first annular portion 125 a and second annular portion 125 b), 126 has an opening 126 a at a position farthest from the negative pressure port 112. The opening 126a is a portion whose flow passage cross-sectional area is smaller than that of the other portion of the connection flow passage 114, and is also a bent portion of the flow passage, and thus corresponds to the flow velocity damping portion. Further, as shown by the arrows in FIG. 7, the connection flow path 114 is separated into two from the negative pressure port 112, and the flow velocity also falls due to the flow hitting at the opening 126a.

  By providing such a flow rate attenuation portion, drainage (a suctioned secretion or the like) in the storage chamber 113 is prevented from flowing into the blower unit 12, and piezoelectric due to the intrusion of drainage into the blower unit 12. A failure or the like of the blower 120 can be suppressed.

  It is preferable that the distance of the shortest path from the negative pressure port 112 to the air inlet 121 via the connection flow path 114 is longer than the linear distance between the negative pressure port 112 and the air inlet 121. For example, the path shown by the arrow in FIG. 7 is the shortest path from the negative pressure port 112 to the intake port 121 generally via the connection flow path 114, and the shortest path is a straight line between the negative pressure port 112 and the intake port 121. The connection channel 114 is designed to be longer than the distance. As a result, failure or the like of the piezoelectric blower 120 due to the inflow of drainage into the blower unit 12 can be suppressed more reliably.

  Further, referring to FIG. 9A, hydrophobic filter 112a is provided at connection port 115 (between negative pressure port 112 and intake port 121) (note that in FIG. 4 to FIG. 6, hydrophobic is provided). Filter 112a is omitted). By providing the hydrophobic filter 112 a, it is possible to suppress the inflow of drainage into the blower unit 12.

  It is preferable that the blower unit 12 and the drainage container 11 be removable. Thus, when drainage is accumulated, only the drainage container 11 can be removed and discarded. The blower unit 12 can also be removed and discarded for each patient.

  In addition, even when the hydrophobic filter 112a is provided in the connection port 115, since the intrusion of bacteria etc. from the drainage container 11 can not be completely prevented, the blower unit 12 is replaced for each patient, and between the patients It is desirable to prevent infection. It is possible to prevent bacteria from invading by using a bacteria filter or the like instead of the hydrophobic filter 112a, but since the pressure loss is large, the suction force is reduced, and the piezoelectric force is maintained to maintain the suction force. It will be necessary to increase the size of the device such as the blower 120 or the like.

(Circuit unit 13)
The circuit unit 13 includes an operation switch 132, a display unit 133, a control unit 131, and a power supply. In addition, they are accommodated in a housing as shown in FIGS. 3 and 4 and the like.

  Although not shown, the power source is electrically connected to each part of the circuit unit 13 and the piezoelectric blower 120 so as to supply power (voltage). This allows driving without the need for an external power supply.

  The control unit 131 can control the drive of the piezoelectric blower 120, and is configured of, for example, a memory control unit (MCU).

  Preferably, the control unit 131 can drive the piezoelectric blower 120 intermittently. By driving the piezoelectric blower 120 intermittently, the power consumption of the suction device can be saved, and the use for a long time becomes possible.

  For example, when the slide switch 132a provided in the circuit unit 13 is turned on, the piezoelectric blower 120 is intermittently driven by the control unit 131 to perform the suction operation intermittently. One suction time and an interval of suction may be appropriately set according to the target patient and the like of suction. Specifically, for example, suction for 20 seconds is performed only once for 5 minutes.

  Although it is desirable that one suctioning time (driving time of the piezoelectric blower 120) be a sufficient time to finish suctioning most of the secretions on the upper part of the cuff, it is unnecessary to reduce power consumption. It is preferable not to lengthen the suction time. Although it is desirable for the suction interval to be such that secretions in the upper part of the cuff do not accumulate too much and increase the risk of VAP, in order to reduce power consumption, the suction interval should not be shortened more than necessary. preferable.

  The drive interval may be switched by the slide switch 132a. Of course, the driving interval and the one-time driving time can be arbitrarily set by circuit design (or microcomputer software etc.).

  Further, the circuit unit 13 is provided with a push switch 132b separately from the slide switch 132a, so that suction can be performed continuously while the switch is pressed.

  In addition, the green LED is turned on during the suction operation, and it can be visually confirmed that the suction operation is being performed. Also, the red (or yellow) LED is configured to light up when the battery level is low.

  The circuit unit 13 can usually be removed for reuse. However, since the circuit unit 13 is also a simple circuit, it may be inexpensive and may be replaced for each patient.

  It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above description but by the scope of claims, and is intended to include all modifications within the scope and meaning equivalent to the scope of claims.

  Reference Signs List 1 suction device, 100 piezoelectric element, 101 diaphragm, 102 pump chamber, 102a discharge hole, 102b metal plate, 103 suction channel, 104 nozzle, 11 drain container, 111 inlet, 112 negative pressure port, 112a hydrophobic filter, 113 storage chamber 114 connection flow path 114a top plate 115 connection port 12 blower unit 120 piezoelectric blower 121 intake port 122 exhaust port 123 exhaust flow path 124 suction port 125 mounting portion 125a first Ring-shaped portion 125b Second ring-shaped portion 13 circuit unit 131 control section 132 operation switch 132a slide switch 132b push switch 133 display section 2 cuff 21 connection tube 22a flow path 22b connection tube 22c , 22d hole, 23a lure Connector, 8 tracheal tube, 8a main channel, 91 trachea, 91a inner wall 92 esophagus, 93 epiglottis 94 oral.

Claims (9)

An exhaust flow path having an exhaust port and an intake port, and a blower unit including a piezoelectric blower provided in the middle of the exhaust flow path;
And a drainage container including a reservoir having an inlet and a negative pressure port;
The air intake port and the negative pressure port are in communication via a connection channel,
The connection channel includes a plurality of branched channels and a flow velocity attenuation unit.
The plurality of flow paths are provided such that the flow of the plurality of flow paths collides in the flow velocity attenuation portion ,
A suction device, wherein a distance of a shortest path from the intake port to the exhaust port via the exhaust flow path of the blower unit is longer than a linear distance between the intake port and the exhaust port.   The suction device according to claim 1, wherein a distance of a shortest path from the negative pressure port to the intake port via the connection flow path is longer than a linear distance between the negative pressure port and the intake port.   A suction device according to any one of the preceding claims, wherein the negative pressure port comprises a hydrophobic filter.   The suction device according to any one of claims 1 to 3, wherein the exhaust port has a connector. The blower unit has a suction port in communication with the inlet of the drainage container,
The blower unit and the drainage container are mounted such that the centers of the suction port of the blower unit and the inlet of the drainage container coincide with each other.
In the mounting portion between the blower unit and the drainage container, a first annular portion centering on the centers of the inflow port and the suction port, and a second annular portion located concentrically with the first annular portion. And an annular part of the
The first annular portion is larger in diameter than the suction port and the inlet, and the second annular portion is larger in diameter than the first annular portion.
The suction device according to any one of claims 1 to 4, wherein the negative pressure port and the intake port are located outside the first annular portion and inside the second annular portion.   The suction device according to any one of claims 1 to 5, wherein the blower unit and the drainage container are removable. Furthermore, it has a circuit unit,
The suction device according to any one of claims 1 to 6, wherein the circuit unit includes a power supply and a control unit that controls driving of the piezoelectric blower.   The suction device according to claim 7, wherein the control unit can intermittently drive the piezoelectric blower. The suction device according to claim 7 or 8, wherein the circuit unit has a removable structure.