JP2014147690A - Fluid infusion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively and simply detect clogging of a tube.SOLUTION: A fluid infusion device comprises: a tube through which a fluid flows; a pump that supplies the fluid to the tube; an electric resistance member that changes electric resistance in association with deformation of the tube; and a determination part that determines the presence or absence of fluid clogging of the tube on the basis of a change in the electric resistance.

Description

  The present invention relates to a fluid injection device.

An insulin pump for injecting insulin into a living body has been put into practical use. A fluid injection device such as an insulin pump is fixed to a living body such as a human body, according to a preset program,
A fluid is regularly injected into a living body such as a human body. At that time, a device for detecting a state in the fluid injection device may be provided so that the injection is appropriately performed.

Patent Document 1 discloses that the component ratio of a two-layer fluid is measured using a change in capacitance.

Japanese Patent Laid-Open No. 11-125616

In the fluid injection device, fluid flows through a tube in the fluid injection device. However,
If the tube is clogged, the fluid cannot be properly sent to a living body such as a human body.
Therefore, it is necessary to detect clogging in the tube. However, if the clogging detection device itself is expensive or complicated, it is difficult to incorporate the clogging detection device into the fluid injection device. Therefore, it is desirable to detect clogging in the tube inexpensively and easily.

The present invention has been made in view of such circumstances, and an object thereof is to detect clogging in a tube easily and inexpensively.

The main invention for achieving the above object is:
A tube for fluid flow;
A pump for feeding the fluid to the tube;
An electrical resistance member whose electrical resistance changes with deformation of the tube;
A determination unit that determines the presence or absence of clogging of the fluid in the tube based on a change in the electrical resistance;
Is a fluid injection device.

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

1 is an overall perspective view of a micropump 1. FIG. 2 is a separation view of the micropump 1. 2 is a permeation top view of the micropump 1. FIG. 1 is a cross-sectional view of a micropump 1. 2 is an internal perspective view of a main body 10. FIG. 3 is a rear perspective view of the main body 10. FIG. FIG. 4 is an exploded perspective view of the cartridge 20. 4 is a rear perspective view of the cartridge base 210. FIG. 2 is a rear perspective view of the micropump 1. FIG. 1 is a block diagram of a micro pump 1. FIG. FIG. 11A is an explanatory diagram of a position where the coiled resistance wire 412 is disposed in the first embodiment, and FIG. 11B is a cross-sectional view taken along line BB in FIG. 11A. It is a circuit diagram of clogging detection part 410 in a 1st embodiment. FIG. 13A is an explanatory diagram of positions where the first electrode 422 and the second electrode 424 are provided in the second embodiment, and FIG. 13B is a cross-sectional view taken along the line CC in FIG. 13A. It is a circuit diagram of the composite detection part 420 in 2nd Embodiment. 15A is a diagram illustrating a voltage input to the input terminal A, FIG. 15B is a diagram illustrating a voltage output from the output terminal B1, and FIG. 15C illustrates a voltage output from the output terminal B2. FIG. It is explanatory drawing of the other shape of the 1st electrode 422. FIG. It is sectional drawing of the micropump in 3rd Embodiment. It is sectional drawing of the micropump in 4th Embodiment.

At least the following matters will become clear from the description of the present specification and the accompanying drawings. That is,
A tube for fluid flow;
A pump for feeding the fluid to the tube;
An electrical resistance member whose electrical resistance changes with deformation of the tube;
A determination unit that determines the presence or absence of clogging of the fluid in the tube based on a change in the electrical resistance;
Is a fluid injection device.

When the fluid is sent by the pump in a state where the tube is clogged, the tube expands due to the pressure. According to the above configuration, by monitoring the electrical resistance that changes with the expansion, the fluid in the tube The presence or absence of clogging can be determined. in this way,
Since an electric resistance member whose electric resistance changes as the tube expands may be provided, clogging in the tube can be detected inexpensively and easily.

In this fluid injection device, it is desirable that the electric resistance member is in close contact with the tube.
By doing in this way, the change of the electrical resistance by the expansion | swelling of a tube can be acquired more reliably.

The electric resistance member is preferably provided on the downstream side of the pump in the flow direction of the fluid in the tube.
By doing in this way, the expansion | swelling of the tube which arises downstream of a pump with the pressure of a pump is acquired reliably, and clogging of a tube can be detected.

The electrical resistance member is preferably a resistance wire whose electrical resistance changes as the tube extends in the circumferential direction.
By doing so, when the tube expands and the tube extends in the circumferential direction, it is possible to determine whether or not the fluid in the tube is clogged by monitoring the change in electrical resistance.

Further, the electric resistance member may be a resistance wire whose electric resistance changes as the tube extends in the longitudinal direction.
By doing so, when the tube expands and the tube extends in the longitudinal direction, it is possible to determine whether or not the fluid in the tube is clogged by monitoring the change in electrical resistance.

The electrical resistance member and the determination unit preferably have the following configuration.
(1) Affixed to a part of the circumference of the tube as a first electrode, and sandwich the tube together with the first electrode.
(2) A second electrode is provided at a position facing the first electrode.
(3) A. The determination unit determines whether or not the fluid is clogged in the tube based on a change in electric resistance of the first electrode.
(3) B. It is determined whether or not bubbles are mixed in the tube based on a change in capacitance between the first electrode and the second electrode.
In this way, it is possible to determine the presence or absence of fluid clogging in the tube based on the change in the electrical resistance of the first electrode, and it is possible to determine whether or not bubbles are mixed in the tube. .

The second electrode is preferably a plate-like member.
By doing in this way, it is possible to reliably detect changes in capacitance and determine whether or not bubbles are mixed in the tube.

Moreover, it is good also as being a resistance wire wound by the circumferential direction of the said tube.
When fluid is sent by the pump in a state where the tube is clogged, the tube expands due to the pressure, but the resistance wire wound in the circumferential direction around the tube extends in the length direction due to this expansion. Change occurs. Therefore, by monitoring this electrical resistance, it is possible to determine the presence or absence of fluid clogging in the tube.

The pump preferably causes the fluid to flow by sequentially squeezing the tube with a plurality of pressing members.
By doing in this way, a fluid can be made to flow appropriately.

The pump may cause the fluid to flow by changing a volume of a container in which the liquid is stored.
By doing so, the fluid can be appropriately flowed.

=== Embodiment ===
FIG. 1 is an overall perspective view of the micropump 1. FIG. 2 is a separation view of the micropump 1. The micropump 1 includes a main body 10, a cartridge 20, and a patch 30. These three bodies are separable as shown in FIG. 2, but are assembled as a unit as shown in FIG. As an example, the micropump 1 is attached to a living body and is suitably used for regular infusion of insulin.

FIG. 3 is a transparent top view of the micropump 1. FIG. 4 is a cross-sectional view of the micropump 1. That is, FIGS. 3 and 4 are views when the main body 10, the cartridge 20, and the patch 30 are assembled. FIG. 5 is an internal perspective view of the main body 10. FIG. 6 shows the main body 10.
FIG. FIG. 6 is a diagram illustrating the back surface of FIG. 5 described above. FIG. 7 is an exploded perspective view of the cartridge 20. FIG. 8 is a rear perspective view of the cartridge base 210. FIG.
FIG. 2 is a rear perspective view of the micropump 1.

Hereinafter, each part of the micropump 1 will be described with reference to FIGS. 1 to 9. First, each part in the main body 10 will be described.

As shown in FIG. 5, the main body 10 includes a main body base 110, each part configured on the main body base 110, and a main body case 130. Each part on the main body base 110 is covered and protected by the main body case 130.

The main body 10 includes a circuit board 140 configured on the main body base 110. Circuit board 14
Reference numeral 0 denotes an electronic board for controlling the piezoelectric motor 150 and the like according to a program and the like. The main body includes a piezoelectric motor 150. The piezoelectric motor 150 is a motor for applying a rotational driving force to the cam 121 described later.

The piezoelectric motor 150 includes a plate-shaped member 151 and a pair of springs 152 (FIG. 3). Spring 1
52 biases the plate-shaped member 151 toward the rotor wheel 128 by its elastic force. The plate-like member 151 is urged toward the rotor wheel 128 as described above, and the front end portion thereof contacts the circumferential surface of the rotor wheel 128.

The plate-like member 151 is a member configured in a layer shape. The plate-shaped member 151 includes a piezoelectric layer and two electrodes, and changes its shape by changing the voltage applied to these two electrodes. For example, longitudinal vibration and bending vibration are alternately repeated according to the applied voltage. The longitudinal vibration changes the length of the plate-shaped member 151 in the axial direction, and the bending vibration changes the plate-shaped member into a substantially S-shape. By repeating these alternately, the rotor wheel 128 is rotated in a predetermined direction.

The rotor wheel 128 has a pinion that rotates integrally at different positions with respect to the height direction of the micropump 1, and this pinion engages with the gear of the intermediate wheel 127 and rotates the intermediate wheel 127. The intermediate wheel 127 also has a pinion that rotates integrally at different positions with respect to the height direction of the micropump, and this pinion engages with a gear that rotates integrally with the output shaft 126. As shown in FIG. 5, the rotor wheel 128, the intermediate wheel 127, and the output shaft 126 are rotatably fixed to individual shafts by a train wheel bridge 125 fixed to the main body 110.

The cam 121 is also fixed to the output shaft 126 pivotally supported by the bearing 129 so as to be integrally rotatable. Then, the cam 121 is also rotated along with the rotation of the output shaft 126. Thereby, the motive power from the piezoelectric motor 150 is transmitted to the cam 121 (FIG. 4).

As shown in FIG. 6, a hook hook 171 is provided at the front of the main body 10 and 2 at the rear.
A hook insertion port 172 is provided at a location. The hook hook 171 has a cartridge 20
Thus, the cartridge 20 can be fixed to the main body 10 by engaging the fixed hook 271 with the hook insertion port 172 (FIGS. 2 and 4).

At this time, since the packing 273 is fitted in the groove on the outer periphery of the upper surface of the cartridge base 210, when the main body 10 and the cartridge 20 are fixed, the cartridge 10 is sealed so that liquid or the like does not enter the space formed by these. can do.

Further, the main body 10 includes a secondary battery storage unit 180 on the back surface (FIG. 6). The secondary battery storage unit 180 includes a battery positive terminal 182 and a battery negative terminal 183. By inserting the secondary battery 181 into the secondary battery storage unit, predetermined power can be supplied to each part of the main body 10. To do.

Next, the cartridge 20 will be described.
The cartridge 20 includes a cartridge base 210 and a cartridge base retainer 240.
And each part configured on the cartridge base. The cartridge base 210 is
As will be described later, the reservoir 290 is configured together with the reservoir film 250.

As shown in FIG. 7, the cartridge base 210 of the cartridge 20 includes a finger unit 220 on the upper surface thereof. The finger unit 220 includes a finger base 227, fingers 222, a tube 225, and finger pressers 226. Further, on the upper surface of the cartridge base 210, a suction connector 228 and a discharge connector 229 are provided. The suction connector 228 is a connector 228 for sucking liquid into the finger unit 220, and the discharge connector 229 is a connector for discharging liquid from the finger unit 220.

A plurality of grooves are formed in the finger base 227, and a suction connector 228 and a discharge connector 229 are inserted into these grooves. Also, finger base 22
7, a tube guide groove 227a for guiding the tube 225 is formed in an arc shape,
A tube 225 is accommodated. One end of the tube 225 is tightly connected to the suction connector 228, and the other end is tightly connected to the discharge connector 229. The material of the tube 225 is, for example, a thermoplastic elastomer such as urethane or styrene.

A plurality of finger guides 227b are formed inside the arc of the tube guide groove 227a.
Each of the finger guides 227 b accommodates the fingers 222. As a result, the tips 222 a of the fingers 222 are arranged so as to be substantially perpendicular to the tube 225.

A finger presser 226 is fixed to the upper surface of the finger base 227 by a fixing screw (not shown). As a result, the finger 222 can slide and move only in the direction along the finger guide 227b.

As described above, since the finger 222 and the tube 225 are provided on the cartridge 20 side, even if the tube 225 has a different diameter, the finger 222 having a length corresponding to the tube diameter is used. Can be provided. Accordingly, even if the cam 121 has a standardized size, the cam surface 121a of the cam 121 can be appropriately disposed at a position where it abuts against the rear end portion 222b of the finger 222.

A patch connection needle 231 is provided on the side surface of the cartridge base 210 to allow liquid to be sent to the patch 30 via the patch septum 350. The patch connection needle 231 communicates with the discharge connector 229. On the other hand, the suction connector 228 communicates with a storage portion 290 to be described later via a through hole provided in the cartridge base 210. As a result, the liquid in the reservoir 290 is removed from the suction connector 228, the tube 225, and the discharge connector 22.
9, and can be supplied to the patch connecting needle 231.

The cartridge 20 includes a reservoir film 250 as shown in FIG. The periphery of the reservoir film 250 is sandwiched between the cartridge base 210 and the film pressing portion 242 provided in the cartridge base pressing member 240. As a result, a reservoir 290 can be formed between the reservoir film 250 and the cartridge base 210, and liquid can be stored in the reservoir 290.

The reservoir film 250 may be fixed to the cartridge base 210 by welding, and the cartridge base holder 240 and the cartridge base 210 may be fixed.

The cartridge base 210 is made of plastic, and the surface on the side where the reservoir film 250 is provided has a curved shape. Thus, although the storage part 290 has a curved surface shape, since the film of the reservoir film 250 can be deformed according to the remaining amount of the liquid stored in the storage part 290, the fluid is stored in the storage part 290. It can be squeezed out so as not to remain. Further, at this time, it is desirable that the reservoir film 250 is processed into a curved surface in a shape along the curved surface shape. By doing in this way, even if the fluid in the storage part 290 decreases, the reservoir film 250 is deformed along the curved surface, so that the liquid can be squeezed out without remaining.

The reservoir film 250 is composed of a multilayer film. At this time, the inner layer is preferably polypropylene, and the outer layer is preferably selected from a material having excellent gas barrier properties.
The reservoir film 250 is not limited to this, and may be, for example, a thermoplastic elastomer or a film in which another material is bonded to the thermoplastic elastomer.

Further, a cartridge septum 280 is provided on the lower surface side of the cartridge 20 (FIG. 9).
). The cartridge septum 280 is inserted into the cartridge septum insertion hole 241 provided in the cartridge base retainer 240 when the cartridge base 210 and the cartridge base retainer 240 are assembled. One surface of the cartridge septum 280 is exposed to the patch base 340 and the openings 340 a and 360 a of the adhesive tape 360 (FIGS. 2 and 9), and the other surface communicates with the fluid inlet 211. The fluid inlet 211 opens between the reservoir film 250 and the cartridge base 210. Therefore, the liquid injected by the injection needle or the like through the cartridge septum 280 is stored in the storage unit 290 (FIG. 8).

Next, the patch 30 will be described mainly with reference to FIG.
The patch 30 includes a catheter 310, an introduction needle 320, an introduction needle folder 321, an introduction needle septum 322, a port base 330, a patch base 340, a patch septum 350, and an adhesive tape 360.

The patch septum 350 is for supplying a liquid into the patch 30 by inserting a patch connection needle 231 as will be described later. Patch septum 350 is patch 3
The patch connecting needle 231 penetrates the patch septum 350 when the reservoir 20 is mounted toward the side surface of the patch 30.

Note that the septum such as the patch septum 350 is formed of a material (for example, silicone rubber, isoprene rubber, butyl rubber, or the like) that closes a hole that is opened by penetrating a needle or the like. Thereby, even if the needle is inserted into and removed from the septum, liquid or the like does not leak through the septum.

The catheter 310 is a tube for injecting liquid. A part of the catheter 310 is held by the port base 330, and a part is exposed to the lower side of the port base 330. Patch 3
When liquid injection is performed using 0, the exposed portion of the catheter 310 is placed inside a living body and the liquid is continuously injected. Therefore, the catheter 310 is formed of a soft material such as a fluororesin or a polyurethane resin that is excellent in biocompatibility.

The introduction needle 320 is a hollow elongated needle-like member, and the outer shape thereof is smaller than the inner diameter of the catheter 310. The introduction needle 320 is inserted into the catheter 320 before use.
The sharp end side of the introduction needle 320 is exposed in the lower direction of the catheter 310, and the other end side is fixed to the introduction needle folder 321. Further, before use, the introduction needle 320 is inserted through an introduction needle septum 322 fixed in the port base 330.

With such a configuration, when the introduction needle folder 321 is pulled out from the port base 330, the introduction needle 320 is pulled out from the catheter 310.
1 does not leak from the introduction needle septum 322 side, and flows into the living body through the catheter 310.

As shown in FIG. 2, the patch 30 includes a patch base 340. Patch base 34
0 is fixed to the port base 330 and includes a cartridge fixing member 341.
The cartridge 20 can be fixed to the patch 30. When the cartridge 20 is connected to the patch 30, the cartridge 20 is slid from the left side of FIG. Then, the patch connection needle 231 provided on the cartridge 20 passes through the patch septum 350 and is inserted into the patch 30 (FIG. 4).

The patch base 340 includes an adhesive tape 360 on the lower surface. Thereby, the micropump 1 can be attached to a living body or the like.

When the main body 10 and the cartridge 20 are assembled, the cam 121 of the main body 10 is inserted into the cam accommodating portion 227c of the finger base 227. Thus, the cam surface 1 of the cam 121
21 a is arranged at a position facing the rear end portion 222 b of the finger 222. Then, the cam surface 121 a comes into contact with the rear end portion 222 b of the finger 222 by the rotation of the cam 121, and the finger 222 can be slid.

When the tube 225 is clogged in the micropump 1 as described above, there arises a problem that a chemical solution or the like cannot be sent to a living body. Therefore, it is desirable that clogging in the tube 225 can be detected inexpensively and easily. In the embodiment shown below, the micropump 1
Provided is a clogging detection unit that can be provided inexpensively and easily.

FIG. 10 is a block diagram of the micropump 1. FIG. 10 shows the controller 141.
A piezoelectric motor 150 and a detector group 400 connected thereto are shown. Detector group 4
00 includes a clogging detection unit 410 (first embodiment) or a composite detection unit 420 (second embodiment) which will be described later. The controller 140 controls the piezoelectric motor 150 according to a program and a signal from the detector group 400.

FIG. 11A is an explanatory diagram of a position where the coiled resistance wire 412 is disposed in the first embodiment. 11B is a cross-sectional view taken along the line BB in FIG. 11A. In FIG. 11A, the tube 22
5, a cam 121, a plurality of fingers 222, a suction connector 228, and a discharge connector 229 are shown.

The cam 121 is formed with four cam peaks. Each cam mountain has a shape such that the height gradually increases from the lowest part of the cam mountain to the highest part, and when reaching the highest part, the cam mountain moves to the lowest part of the adjacent cam mountain. With this shape, when the cam 121 rotates, the tip portions 222a of the plurality of fingers 222 sequentially press the tubes 225 in the direction from the suction connector 228 side toward the discharge connector 229 side. And tube 225
The liquid inside can be sent from the suction connector 228 side to the discharge connector 229 side. That is, the discharge connector 229 side is downstream of the suction connector 228.

The coiled resistance wire 412 is provided on the downstream side of the pump constituted by the plurality of fingers 222. The coiled resistance wire 412 corresponds to an electrical resistance member whose electrical resistance changes as the tube 225 is deformed. As shown in FIG. 11B, the coiled resistance wire 412 is
The resistance wire is configured by being wound a plurality of times in the circumferential direction of the tube 225.

If the tube 225 is clogged downstream of the finger 222, the tube 225 expands due to the pressure with which the finger 222 sends fluid. This expansion causes the coiled resistance wire 412 wound around the tube 225 in the circumferential direction to extend in the length direction of the resistance wire, so that the electrical resistance changes. Specifically, since the length of the resistance wire is increased, the electric resistance value is increased. Therefore, by monitoring the electric resistance value of the coiled resistance wire 412, it is possible to detect the presence or absence of fluid clogging in the tube 225.

FIG. 12 is a circuit diagram of the clogging detection unit 410 in the first embodiment. FIG. 12 shows a cross section of the tube 225 and a coiled resistance wire 412 wound around the tube 225. Here, the resistance value of the coiled resistance wire 412 is shown as r.

One end of the coiled resistance wire 412 is shown as an input end X, and the other end of the coiled resistance wire 412 is shown as an output end Y. Both the input terminal X and the output terminal Y are not shown in the controller 1
41. The controller 141 applies a voltage e to the input terminal X. Then, the controller 141 detects the current value returned to the controller 141, and detects the clogging of the tube 225 according to the detected current value.

If there is no change in the diameter of the tube 225, the resistance value of the coiled resistance wire 412 is maintained at r, so the current value i returned to the controller 141 is i = e / r. on the other hand,
When the tube 225 is clogged and the diameter of the tube 225 increases, the coiled resistance wire 4
Since 12 is extended, its resistance value is (r + Δr). Therefore, the current value i returned to the controller 141 is i = e / (r + Δr).

When the current value i falls below a predetermined current value, the controller 141 causes the tube 225 to
It is determined that clogging has occurred. By doing in this way, it can be determined whether the tube 225 is clogged cheaply and easily.

FIG. 13A is an explanatory diagram of positions where the first electrode 422 and the second electrode 424 are disposed in the second embodiment. 13B is a cross-sectional view taken along the line CC in FIG. 13A. FIG. 13C is a partial top view and a partial bottom view of the tube 225. FIG. 13A shows a tube 225, a cam 121, a plurality of fingers 222, a suction connector 228, and a discharge connector 229, as in the first embodiment.

In the second embodiment, the first electrode 422 and the second electrode 424 are provided on the downstream side of the finger 222. The first electrode 422 and the second electrode 424 are provided at positions facing each other with the tube 225 interposed therebetween. As a result, as will be described later, it is possible not only to detect clogging occurring in the tube 225 but also to detect bubbles generated in the tube 225.

The first electrode 422 is attached to the tube 225, and when the tube 225 is deformed, the first electrode 422 is also deformed accordingly. As shown in FIG. 13C, the first electrode 422 has a 1
A plurality of resistance wires are bent and formed so that a plurality of the resistance wires are arranged in parallel in the longitudinal direction of the tube 225 and attached to the upper surface side of the tube 225. In this way, the electrical resistance can be changed by the circumferential extension of the tube 225. On the other hand, the second
The electrode 424 is a plate-like member as shown in FIG. 13C and is provided in contact with the lower surface of the tube 225. In this way, the first electrode 422 and the second electrode 424 constitute a capacitor. And it is supposed that the change of the electrostatic capacitance by the change of the fluid in a tube will be caught.

FIG. 14 is a circuit diagram of the composite detection unit 420 in the second embodiment. FIG. 14 shows a cross section of the tube 225, a first electrode 422 attached to the upper surface of the tube 225, and a second electrode 424 provided on the lower surface of the tube 225. One end of the first electrode 422 is an input end A. The input terminal A is connected to the controller 141. Also, the first electrode 422
The other end of the resistor is connected in parallel with a resistor R4 and a capacitor C1, and the other end is grounded. The other end of the first electrode 422 has an output end B1.

The second electrode 424 is connected to the resistor R3 and the anode of the diode D. The other end of the resistor R3 is grounded. The cathode of the diode D constitutes the output terminal B2. A capacitor C2 is connected in parallel to the output terminal B2. The other end of the capacitor C2 is grounded. The output terminal B1 and the output terminal B2 are also connected to the controller 141.

FIG. 15A is a diagram illustrating a voltage input to the input terminal A. FIG. FIG. 15B is a diagram illustrating a voltage output from the output terminal B1. FIG. 15C is a diagram illustrating a voltage output from the output terminal B2.

An AC voltage having a reference voltage E1 and an amplitude α is applied to the input terminal A as shown in FIG. 15A. In the circuit shown in FIG. 14, a resistor R4 and a capacitor C1 constitute a low pass filter. Therefore, the AC component is removed by the low-pass filter, and the output terminal B
From 1, a direct current component as shown in FIG. 15B is output. Here, the voltage value V1 output from the output terminal B1 can be obtained by V1 = E1 × R1 / R4. Where resistance R
1 is the resistance value of the first electrode 422. The tube 225 is clogged and the finger 22
When the pressure in the tube 225 increases by the operation 2, the tube 225 expands. Since the first electrode 422 is extended, the resistance value of the first electrode 422 is R1 + ΔR. Therefore, the voltage V1 output from the output terminal B1 is V1 = E1 × (R1 + ΔR) / R4. That is, when clogging occurs, the voltage value output from the output terminal B1 increases.

The controller 141 determines that the tube 225 is clogged when the voltage value output from the output terminal B1 exceeds a predetermined voltage value. By doing in this way, it can be determined whether the tube 225 is clogged cheaply and easily.

On the other hand, a DC component as shown by the solid line in FIG. 15C is output from the output terminal B2. In addition, what is shown with the broken line in FIG. 15C is the output at B3 in FIG. As described above, the capacitor is configured by sandwiching the tube 225 between the first electrode 422 and the second electrode 424. At this time, a fluid such as a chemical solution is flowing in the tube 225 without bubbles and the like being mixed therein.

The output at B3 at this time is a voltage indicated by a broken line in FIG. 15C. The direct current component output by half-wave rectification by the diode D and the capacitor C2 is the output at B2.

In such a configuration, if bubbles are mixed into the tube 225, the air has a smaller capacitance than the liquid, so that the amplitude at B3 (β in FIG. 15C) increases. Therefore, the voltage at the output terminal B2 that is output after being half-wave rectified also increases.

The controller 141 determines that bubbles are mixed into the tube 225 when the voltage value output from the output terminal B2 exceeds a predetermined voltage value. In this way, not only can the clogging in the tube 225 be detected, but also the presence or absence of bubbles mixed in the tube 225 can be determined.

Here, the presence / absence of bubbles mixed in the tube 225 is determined based on the voltage at the output terminal B2, but if the capacitance of the capacitor formed by the first electrode 422 and the second electrode 242 changes, B3 A change also occurs in the phase difference of the alternating current detected at δ (δ in FIG. 15C). Therefore, it is good also as determining the presence or absence of the bubble mixed in the tube 225 based on the change of the phase difference of the alternating current detected in B3.

FIG. 16 is an explanatory diagram of another shape of the first electrode 422. In the second embodiment, the first electrode has been described as a shape in which one resistance wire is bent and a plurality of the resistance wires are arranged in parallel in the longitudinal direction of the tube 225. FIG. The tube 225
It is good also as a shape shape | molded so that a some parallel line may line up in the direction which cross | intersects the longitudinal direction. By doing in this way, it can be set as the shape where an electrical resistance changes more easily by extension of the tube 225 in the longitudinal direction.

Further, the shape of the first electrode described in the second embodiment and the shape of the electrode indicated by 426 in FIG. 16 may be used as the resistance line in the first embodiment. In the first embodiment, bubble detection may be performed by applying an AC waveform as in the second embodiment.

In the above-described embodiment, the liquid is pumped by a pump of a type in which the plurality of fingers 22 sequentially squeeze the tube 21, but the type of pump is not limited thereto.

FIG. 17 is a cross-sectional view of the micropump in the third embodiment. In the third embodiment,
Although the pump portion is different from that of the first embodiment, other configurations are the same as those of the first embodiment.
Therefore, here, the syringe type pump 28 in the third embodiment will be described with reference to FIG.

The syringe-type pump 28 includes a cylindrical portion 281, an end wall 282, and a lead screw 283 plunger 28.
4, an insert 285, and a gear 287. Further, as described later, a small gear (not shown) that engages with the gear 287 and a motor (not shown) for rotating the small gear 288 are provided.

The side wall 281 </ b> B inside the cylindrical portion 281 is an inner wall having a substantially cylindrical shape that extends coaxially with the lead screw 283. A plunger 284 having a substantially cylindrical shape so as to be in close contact with the side wall 281B.
Is inserted. An insert 285 is fixed inside the plunger 284. The insert 285 is formed with an internal thread that can be engaged with the lead screw 283. And plunger 2
84, a liquid chamber 289 is formed between the side wall 281B and the end wall 283.

The plunger 284 is provided with a slide protrusion 283A extending in the same direction as the lead screw 283. On the other hand, the side wall 281B has a slide recess 28 that engages with the slide protrusion 283A.
1A is provided. This restricts the rotation of the plunger 284 while the lead screw 2
83 to allow movement of the plunger 284 in the coaxial direction.

The lead screw 283 extends from the end wall 282 to the opening side of the cylindrical portion 281 in the cylindrical portion 281. The end of the lead screw 283 on the opening side has a gear 287 that can rotate coaxially.
Is fixed. A small gear (not shown) is engaged with the gear 287. And this small gear has
A motor (not shown) is connected. By doing so, the rotation of the lead screw 283 can be controlled by controlling the rotation of the motor.

A tube 291 is connected to the end wall 282. The tube 291 is branched in the middle, and one branched tube 291 </ b> A is connected to the connection needle 233. The other branched tube 291B is connected to a supply path 231A communicating with the storage unit 26.

The tube 291 is provided with a switching valve 292 that switches the flow path to the tube 291A or the tube 291B. Then, when the switching valve 292 is switched so that the liquid can flow from the tube 291B to the tube 291, the plunger 284 is moved in the direction in which the liquid chamber 289 expands, so that the liquid is discharged from the storage unit 26. Liquid can flow into the chamber 289. Further, when the switching valve 292 is switched so that the liquid can flow from the tube 291 to the tube 291A, the plunger 284 is moved in the direction in which the liquid chamber 289 is contracted, thereby connecting from the liquid chamber 289. Liquid can flow into the needle side 233.

In such a micropump 1, a coiled resistance wire 412 is attached to the tube 291 </ b> A, as in the first embodiment. Then, the clogging detection unit 410 can be applied to such a coiled resistance wire 412 as in the first embodiment. By doing in this way, based on the electric current value returned to the controller 141, it can be determined whether or not clogging has occurred on the downstream side of the tube 291A.

Further, similarly to the second embodiment, the first electrode 422 and the second electrode 424 can be arranged so as to face each other at the position where the coiled resistance wire 412 is provided. And the composite detection part 420 in 2nd Embodiment is applicable with respect to these. By doing so, it is possible to determine whether or not clogging has occurred on the downstream side of the tube 291A based on the principle described in the second embodiment. In addition, air bubbles in the tube 291A can be detected based on the principle described in the second embodiment.

In the third embodiment, the storage section 26 and the liquid chamber 289 are provided separately. However, the following type of micropump 1 in which the liquid chamber also serves as the storage section may be employed.

FIG. 18 is a cross-sectional view of the micropump 1 in the fourth embodiment. 18 shows a reservoir 530, a dispenser 540, a local processor 550, a wireless receiver 560, an outlet port assembly 570, a power source 580, and a tube 59 contained in a housing 520.
A micropump 1 with 0 is shown.

The reservoir 530 stores a liquid to be administered to a living body or the like via the outlet port assembly 570. The dispenser 540 applies pressure to the chemical by changing the volume in the reservoir 530 and causes the liquid to flow to the tube 590 and the outlet port assembly 570.

Wireless receiver 560 receives a command from a remote control device (not shown). Then, the command is sent to the local processor 550. The local processor 550 receives the dispenser 54
0 is controlled to apply pressure to the liquid in the reservoir 530 as described above. The power supply 580 is
Power is supplied to the wireless receiver 560 and the local processor 550.

In such a micropump 1 as well, the tube 59 is the same as in the first embodiment.
At 0, a coiled resistance wire 412 is attached. Then, the clogging detection unit 410 can be applied to such a coiled resistance wire 412 as in the first embodiment. By doing so, based on the current value returned to the controller 141,
It can be determined whether or not clogging has occurred on the downstream side of the tube 590.

Further, as in the second embodiment, the first electrode 422 and the second electrode 424 can be disposed so as to face each other at the position where the coiled resistance wire 412 is provided as described above. And the composite detection part 420 in 2nd Embodiment is applicable with respect to these. By doing so, it is possible to determine whether or not clogging has occurred on the downstream side of the tube 590 based on the principle described in the second embodiment. In addition, air bubbles in the tube 590 can be detected based on the principle described in the second embodiment.

=== Other Embodiments ===
The above-described micropump 1 is also referred to as a fluid administration device. The tube in the micropump 1 is also called a cannula.

The above-described micropump 1 can be reduced in size and thickness, and can stably flow continuously at a very small flow rate. Therefore, the micropump 1 can be attached to a living body or on the surface of a living body to develop a new drug or perform drug delivery. Suitable for use. Moreover, in various mechanical devices, it can be mounted in the device or outside the device and used for transporting fluids such as water, saline, chemicals, oils, fragrances, inks and gases. Further, the micropump alone can be used for fluid flow and supply.

The above-described embodiments are for facilitating the understanding of the present invention, and are not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof.

1 Micro pump 10 body, 20 cartridge,
30 patches,
110 body base,
121 cam, 121a cam surface,
125 wheel train, 126 output shaft, 127 intermediate wheel,
128 rotor cars, 129 bearings,
130 body case, 140 circuit board, 141 controller,
150 piezoelectric motor, 151 plate member, 152 spring,
171 hook hook, 172 hook insertion slot,
180 Secondary battery compartment, 181 Secondary battery,
182 battery positive terminal, 183 battery negative terminal,
210 cartridge base, 211 fluid inlet,
220 finger units,
222 fingers, 222a front end, 222b rear end,
225 tube, 226 finger press,
227 finger base,
227a tube guide groove, 227b finger guide, 227c cam housing,
228 Connector for suction, 229 Connector for discharge,
231 patch connecting needle,
240 Cartridge base holder,
241 Cartridge septum insertion hole, 242 Film holding part,
250 reservoir film,
271 fixed hook, 272 fixed hook, 273 packing,
280 cartridge septum, 290 reservoir,
310 catheter, 320 introducer needle, 321 introducer needle folder,
322 Introducing septum,
330 port base, 340 patch base, 340a opening,
341 cartridge fixing member,
350 patch septum, 360 adhesive tape, 360a opening,
400 detector group, 410 clogging detection unit, 412 coiled resistance wire,
420 composite detection unit, 422 first electrode, 424 second electrode,
426 other shapes of the first electrode,
520 housing, 530 reservoir, 540 dispenser,
550 local processor, 560 wireless receiver, 570 outlet port assembly,
580 power supply, 590 tube

Claims (10)

A tube for fluid flow;
A pump for feeding the fluid to the tube;
An electrical resistance member whose electrical resistance changes with deformation of the tube;
A determination unit that determines the presence or absence of clogging of the fluid in the tube based on a change in the electrical resistance;
A fluid injection device comprising: The fluid injection device according to claim 1,
The fluid injection device, wherein the electric resistance member is in close contact with the tube. The fluid injection device according to claim 1 or 2,
The fluid injection device according to claim 1, wherein the electric resistance member is provided on a downstream side of the pump in a flow direction of the fluid in the tube. The fluid injection device according to any one of claims 1 to 3,
The fluid injecting apparatus according to claim 1, wherein the electric resistance member is a resistance wire whose electric resistance changes as the tube extends in the circumferential direction. The fluid injection device according to any one of claims 1 to 3,
The fluid injecting apparatus according to claim 1, wherein the electric resistance member is a resistance wire whose electric resistance changes as the tube extends in the longitudinal direction. A fluid injection device according to any one of claims 1 to 5,
The electrical resistance member is attached to a part of the circumference of the tube as a first electrode,
Sandwiching the tube together with the first electrode, and having a second electrode at a position facing the first electrode;
The determination unit determines whether or not the fluid is clogged in the tube based on a change in electric resistance of the first electrode, and changes the capacitance between the first electrode and the second electrode. And determining whether or not air bubbles are mixed in the tube. The fluid injection device according to claim 6,
The fluid injection device, wherein the second electrode is a plate-like member. The fluid injection device according to any one of claims 1 to 3,
The fluid injection device according to claim 1, wherein the electric resistance member is a resistance wire wound in a circumferential direction of the tube. A liquid injection device according to any one of claims 1 to 8,
The fluid injection device according to claim 1, wherein the pump causes the fluid to flow by sequentially squeezing the tube with a plurality of pressing members. A liquid injection device according to any one of claims 1 to 8,
The fluid injection device according to claim 1, wherein the pump causes the fluid to flow by changing a volume of a container in which the liquid is stored.