WO2013047857A1

WO2013047857A1 - Medical solution administration device and blockage detection method

Info

Publication number: WO2013047857A1
Application number: PCT/JP2012/075278
Authority: WO
Inventors: 昭彦八木
Original assignee: テルモ株式会社
Priority date: 2011-09-28
Filing date: 2012-09-24
Publication date: 2013-04-04
Also published as: JP5909066B2; JP2013070863A

Abstract

In order to greatly improve usability, a medical solution administration device (1) detects the state of a flow path on the basis of the temperature changes of an upstream temperature detection signal (SU) and a downstream temperature detection signal (SL) in each pushing operation of a piston (11), and when detecting that there is a possibility that a flow path is blocked, continues the next pushing operation of the piston (11) when in the previous pushing operation of the piston (11), the interior of a detection tube (13B) in a position where a heating temperature detector (17) is provided is changed from the state of being filled with a medical solution (MS) to the state in which air bubbles (AR) are present. Consequently, the medical solution administration device (1) can continue the administration of the medical solution without erroneously determining the state in which air bubbles are mixed in the flow path as the state in which the flow path is blocked. Thus, the medical solution administration device (1) can greatly improve usability.

Description

Chemical solution administration device and occlusion detection method

The present invention relates to a drug solution administration device and an occlusion detection method, and is suitable for application when, for example, a drug solution is administered into the body.

2. Description of the Related Art Conventionally, as a device for administering a drug solution (insulin), it is a portable device that is used by being attached to a user's skin, and a drug solution filled in an outer cylinder that is a drug solution container is passed through a seal member (piston). A so-called syringe pump type device has been proposed that is administered into the body by being pushed out (see, for example, Patent Document 1).

Special table 2010-501283

By the way, in the device that administers the chemical solution as described above, the chemical solution filled in the outer cylinder is denatured or the cannula inserted into the user's body is deformed and the flow path through which the chemical solution flows is blocked, The drug solution may not be properly administered to the user.
In order to notify the user that the flow path is blocked, a pressure sensor is provided in the flow path to detect the pressure of the flow path through which the chemical solution flows, and the flow path is blocked if the pressure is equal to or greater than a predetermined threshold. Therefore, an apparatus has been proposed in which the operation is stopped and the user is notified that the chemical is not normally delivered.
On the other hand, as a drug solution administration device for administering a drug solution, a so-called piston pump type of administering a drug into the body by moving the piston in the pull back direction, pulling out the drug solution from the drug solution container, moving the piston in the pushing direction and pushing out the drug solution. A device has been proposed.
In such a piston pump type device, when the blockage is detected by the pressure sensor described above, the blockage may not be detected because the pressure in the flow path does not sufficiently increase even if the piston is moved in the pushing direction. .
For this reason, by forming a thermal marker, which is a region where a temperature difference with the surroundings is intentionally formed in a part of the flow path, and detecting how the thermal marker moves due to the pushing operation of the piston, There is a method for detecting blockage of a flow path.
In the case of blockage detection using such a thermal marker, when the flow path is closed, the chemical does not flow in the flow path, so the thermal marker does not move, and the detection unit has a large temperature before and after the piston pushing operation. Does not detect changes.
Thus, when a detection part does not detect a big temperature change before and after the pushing operation of a piston, it can be judged that the chemical | medical solution administration apparatus has obstruct | occluded the flow path.
By the way, bubbles may be mixed into the flow channel from, for example, a chemical solution container. When bubbles are mixed into the flow path, thermal markers are not formed on bubbles with a lower thermal conductivity than the chemical solution, so even if the bubbles move in the flow path near the detection section due to the pushing operation of the piston, the detection section Does not detect large temperature changes before and after the piston pushing operation.
For this reason, the chemical solution administration device may erroneously determine that the state where air bubbles are mixed in the flow path is a state where the flow path is blocked and stop the operation, which may deteriorate the usability.
The present invention has been made in view of the above points, and an object of the present invention is to propose a drug solution administration device and an occlusion detection method that can further improve usability.
In order to solve such a problem, the present invention is a portable liquid medicine administration device that is held by a user and administers a liquid medicine into the body of the user, and includes a determination unit and a liquid medicine storage unit that stores the liquid medicine And a flow path part that forms a flow path for sending a chemical liquid from the chemical liquid storage part into the user's body, a cylinder connected at one end to the flow path part, and slides inside the cylinder, A piston that feeds the chemical liquid into the body of the user through the flow path portion by a pushing operation that moves from the opposite side of the one end to the one end side of the cylinder; and a downstream side of the flow path portion from the cylinder. A heater for heating the flow path part, and a temperature detection provided in the vicinity of the heater or on the downstream side of the flow path part for detecting the temperature of the flow path part and sending it as a temperature detection signal And the pushing motion of the piston Each time, based on the temperature change of the temperature detection signal, it is determined whether there is a possibility that air bubbles are present in the flow path part, and further, a flow path state determination part that determines whether it is in a closed state or not And.
According to the present invention, in a portable chemical solution administration device that is held by a user and administers the chemical solution into the user's body, the chemical solution is sent from the chemical solution storage unit that stores the chemical solution to the user's body. The chemical solution in the flow path section that forms the liquid flow path is heated by a heating element, and the temperature of the flow path section is detected by a temperature detector provided in the vicinity of the heating element or downstream of the flow path section. A blockage detection method for detecting blockage of the flow path part by sliding inside a cylinder having one end connected to the flow path part and moving from the opposite side of the cylinder to the one end side Thus, the temperature detection provided on the downstream side of the flow channel portion with respect to the cylinder each time the piston is pushed through the flow channel portion into the user's body through the flow channel portion. The child Determining whether there is a possibility that air bubbles are present in the flow path portion based on a temperature change of the temperature detection signal that has detected, and further determining whether the flow path portion is in a closed state And a step of performing.
Thereby, a chemical | medical solution administration can be continued, without misjudging the state in which the bubble mixed in the flow path as the state which the flow path obstruct | occluded.
ADVANTAGE OF THE INVENTION According to this invention, it can discriminate | determine and determine without misjudging the state where the bubble mixed in the flow path, and the state where the flow path was blocked, and the medicinal solution administration device and the blockage detection method that can further improve the usability can be realized.

FIG. 1 is a schematic diagram illustrating a configuration of a drug solution administration device.
FIG. 2 is an exploded perspective view of the chemical liquid administration device.
FIG. 3 is a schematic diagram illustrating the configuration of the sending unit.
FIG. 4 is a schematic diagram illustrating the configuration of the sending unit.
FIG. 5 is a schematic diagram illustrating an electrical configuration of the drug solution administration device.
FIG. 6 is a schematic diagram illustrating a temperature detection pattern in a chemical fluid flow state.
FIG. 7 is a schematic diagram illustrating a temperature detection pattern in a bubble change state.
FIG. 8 is a schematic diagram showing a temperature detection pattern in a bubble state.
FIG. 9 is a schematic diagram illustrating a temperature detection pattern in a closed state.
FIG. 10 is a schematic diagram illustrating a functional configuration of the CPU according to the first embodiment.
FIG. 11 is a flowchart illustrating a blockage detection processing procedure according to the first embodiment.
FIG. 12 is a schematic diagram illustrating a functional configuration of a CPU according to the second embodiment.
FIG. 13 is a flowchart illustrating a blockage detection processing procedure according to the second embodiment.
FIG. 14 is a schematic diagram illustrating a temperature detection pattern in a chemical fluid flow state.
FIG. 15 is a schematic diagram illustrating temperature detection patterns in a chemical solution state and a bubble change state.
FIG. 16 is a schematic diagram illustrating a temperature detection pattern in a bubble change state.
FIG. 17 is a schematic diagram illustrating a temperature detection pattern in a bubble state.
FIG. 18 is a schematic diagram illustrating a temperature detection pattern in a closed state.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
<1. First Embodiment>
[1-1. Configuration of drug administration device]
As shown in FIG. 1, the drug administration device 1 is a portable device that is used by being attached to a user's skin, and has a lower housing portion that is open on the upper side and has a space inside. 2 and the upper housing part 3 fitted in the opening of the lower housing part 2 are formed into a flat and substantially rectangular parallelepiped shape.
The size of the drug administration device 1 may be reduced to such an extent that it can be affixed to the user's skin, and examples thereof include a substantially rectangular parallelepiped shape having a width of 32 mm, a length of 44 mm, and a height of 11 mm.
The lower housing part 2 is provided with a sticking part 4 made of double-sided tape or the like on the bottom surface 2A. The medicinal-solution administration device 1 is held by the user when the affixing portion 4 is affixed to the user's skin.
The medicinal solution administration device 1 includes a puncture unit 5 made of a needle, a cannula or the like that punctures the user's skin in order to administer the medicinal solution filled therein to the bottom surface 2A of the lower casing unit 2 into the user's body. In addition, there is provided an injection part 6 which is an injection path for injecting the chemical liquid into the chemical liquid storage part 7 (FIG. 2) provided inside.
As shown in FIG. 2, the drug solution administration device 1 includes an injection unit 6, a drug solution storage unit 7, a substrate unit 8, and a delivery unit 9 in a space formed by the lower housing unit 2 and the upper housing unit 3. The
The chemical solution storage unit 7 is a container formed of a flexible material. As a material which comprises the chemical | medical solution storage part 7, it is preferable that a polyolefin is included, for example. As a material for forming a flexible bag, polyethylene, polypropylene, styrene thermoplastic elastomer such as styrene-butadiene copolymer or styrene-ethylene-butylene-styrene block copolymer, or ethylene-propylene copolymer, A soft resin obtained by blending and softening an olefinic thermoplastic elastomer such as an ethylene-butene copolymer or a propylene-α-olefin copolymer can be given. Although the capacity | capacitance of the container of the chemical | medical solution storage part 7 is not specifically limited, For example, a 2 mL capacity | capacitance is mentioned when size reduction etc. are considered.
The chemical solution storage unit 7 is filled with a chemical solution from the outside through the injection unit 6. Examples of the drug solution stored in the drug solution storage unit 7 include analgesics such as insulin, various hormones, morphine, and anti-inflammatory drugs. The substrate unit 8 is provided with a power supply unit 44 (FIG. 5) for supplying power supply power, a circuit for controlling the sending unit 9, and the like.
As shown in FIGS. 2, 3 and 4, the delivery unit 9 includes a piston 11, a drive unit 12 that drives the piston 11 to reciprocate according to the control of the CPU 41 (FIG. 5), a drug solution storage unit 7 to a puncture unit 5. A flow path portion 13 that forms a flow path through which a chemical solution flows, a cylinder 14 in which one end is connected to the flow path portion 13 and a piston 11 inserted from the other end is slid inside, and a chemical solution is allowed to pass only in one direction. The directional valve 15 is included.
The piston 11 is driven by the drive unit 12 and slides with a predetermined stroke in the cylinder 14. Examples of the material of the piston 11 include stainless steel, copper alloy, aluminum alloy, titanium material, thermoplastic elastomer such as polypropylene and polycarbonate, and the outer diameter is about 0.8 mm, for example. The piston 11 slides in the cylinder 14 to send a certain amount of chemical solution, and its stroke is, for example, about 2 mm.
The flow path portion 13 connects the suction pipe 13 </ b> A that forms the inflow path, the detection pipe 13 </ b> B that passes through the temperature detection section 16, the delivery pipe 13 </ b> C that forms the outflow path, and the flow path section 13 to the cylinder 14. A connecting pipe 13D for connecting the detecting pipe 13B and the connecting pipe 13D.
The suction pipe 13A has one end connected to the chemical solution storage unit 7 and the other end connected to the connection pipe 13D. The detection tube 13B has one end connected to the delivery tube 13C and the other end connected to the connection tube 13E. The delivery tube 13C has one end connected to the puncture unit 5 and the other end connected to the detection tube 13B. The connection pipe 13D has ends connected to the suction pipe 13A and the connection pipe 13E, respectively, and the cylinder 14 is connected to the center portion. The ends of the connection pipe 13E are connected to the connection pipe 13D and the detection pipe 13B, respectively.
The detection tube 13B has an internal cross-sectional area so that the chemical liquid MS is sufficiently moved when the piston 11 reciprocates once. For example, the detection tube 13B is configured by a pipe having an inner diameter of 0.4 mm (preferably a pipe made of stainless metal). ing. The suction pipe 13A, the delivery pipe 13C, and the connection pipe 13E are configured by pipes (preferably stainless metal) having an inner diameter of 1 mm or less. The detection tube 13B, the delivery tube 13C, and the connection tube 13E may be configured integrally, but at this time, the cross-sectional area is set to match the cross-sectional area of the detection tube 13B.
Between the suction pipe 13A and the connection pipe 13D, there is provided a one-way valve 15A which is an elastically deformable so-called umbrella valve made of, for example, rubber and allows the chemical liquid to pass from the suction pipe 13A to the connection pipe 13D only in one direction. . Between the connecting pipe 13D and the connecting pipe 13E, there is provided a one-way valve 15B that allows the chemical solution to pass from the connecting pipe 13D to the connecting pipe 13E only in one direction.
The cylinder 14 has an inner diameter larger than the outer diameter of the piston 11, one end is connected to the connecting pipe 13D, and the piston 11 is inserted from the other end side and slides inside. The difference between the inner diameter of the cylinder 14 and the outer diameter of the piston 11 is, for example, about 0.01 mm.
As shown in FIG. 3, when sending the chemical solution from the chemical solution storage unit 7 to the outside, the delivery unit 9 is the most retracted position (hereinafter referred to as the most pushed position) from the position where the piston 11 is most pushed in (hereinafter also referred to as the most pushed position). (Also referred to as a retraction position) in the cylinder 14 (hereinafter, this sliding direction is also referred to as a retraction direction), and the chemical stored in the chemical storage section 7 is transferred to the cylinder via the suction pipe 13A and the connection pipe 13D. 14 suck out.
When the piston 11 is moved to the most retracted position, the delivery section 9 slides the piston 11 in the cylinder 14 from the most retracted position to the most pushed position as shown in FIG. (The direction is also referred to as the pushing direction.) The chemical liquid sucked into the cylinder 14 is sent out into the user's body through the connecting tube 13D, connecting tube 13E, detection tube 13B, delivery tube 13C and puncture unit 5.
The delivery unit 9 can administer about 1 μL of a chemical solution into the user's body by reciprocating the piston 11 once. By repeating this operation at a set cycle and interval, the chemical solution can be delivered at a desired administration rate and dosage. Can be administered to the user.
In practice, the drug solution administration device 1 has a basal mode in which a drug solution is intermittently administered to a user over a period of 24 hours (for example, once every 6 minutes), and a large amount of drug solution before a meal or during hyperglycemia. It operates in two types of administration modes: a bolus mode for additional administration to the user.
[1-2. Configuration of temperature detector]
The temperature detector 16 includes a heating temperature detector 17 that is a thermistor attached to the outside of the detection tube 13B that is downstream of the piston 11 in the flow direction in the flow path portion 13, and the heating temperature detector 17. The temperature detector 18 is a thermistor attached to the outside of the detection tube 13B on the downstream side.
The heating temperature detector 17 and the temperature detector 18 are arranged in the detection tube 13B at a predetermined interval from each other. The heating temperature detector 17 generates Joule heat by causing a current to flow through the thermistor at predetermined time intervals, and repeats a heating operation for heating the chemical liquid MS in the detection tube 13B to form a thermal marker MK. At the same time, the heating temperature detector 17 measures the resistance value of the thermistor whose resistance value varies with temperature, and detects the temperature of the detection tube 13B at the position where the heating temperature detector 17 is provided.
The temperature detector 18 measures the resistance value of a thermistor whose resistance value varies with temperature, and detects the temperature of the detection tube 13B at the position where the temperature detector 18 is provided.
Here, in the delivery section 9, the distance between the heating temperature detector 17 and the temperature detector 18 is the inter-sensor distance L, the cross-sectional area inside the detection tube 13B in the temperature detection section 16 is the flow path cross-sectional area A, When the amount of pushing out the chemical MS when the piston 11 reciprocates once is defined as a volume stroke amount V, the equation (1) is established.

Thereby, the chemical liquid administration device 1 detects the temperature of the thermal marker MK formed in the detection tube 13B in the vicinity of the heating temperature detector 17 by heating the chemical liquid MS by the heating temperature detector 17 by one pushing operation of the piston 11. It can reach the child 18.
Incidentally, when the inter-sensor distance L is small with respect to the volume stroke amount V, the temperature detector 16 is difficult to detect the temperature difference between the heating temperature detector 17 and the temperature detector 18.
Actually, in the drug administration device 1, the distance L between the sensors is 4 mm, the cross-sectional area A of the flow path is 0.125 mm 2, and the volume stroke amount V is 1 μL.
[1-3. Electrical configuration of drug solution administration device]
As shown in FIG. 5, the drug administration device 1 includes a CPU (Central Processing Unit) 41, a ROM (Read Only Memory) 42, a RAM (Random Access Memory) 43, a power supply unit 44, an interface unit (I / F). Part) 45, notifying part 46, driving part 12, heating temperature detector 17 and temperature detector 18 are connected via a bus 47.
The CPU (determination unit) 41, the ROM 42, the RAM 43, the power supply unit 44, and the notification unit 46 are arranged on the substrate unit 8 (not shown). A battery is applied to the power supply unit 44. As the notification unit 46, a speaker for notification by voice, an LED for notification by light, and the like are applied.
The interface unit 45 is provided with a button (not shown) or the like that is arranged in the upper casing unit 3 or the lower casing unit 2 and receives a user input command. In addition, a communication unit including an antenna and a communication circuit for performing wireless communication instead of the interface unit 45 is installed, and an input command by wireless communication is received from an operation unit (not shown) separate from the pump. But you can.
The CPU 41 performs overall control by reading the basic program stored in the ROM 42 into the RAM 43 and executing it, and also reads out and executes the various application programs stored in the ROM 42 into the RAM 43 to execute various processes / processes in each operation process. Perform judgment (judgment). The user operates the drug solution administration device 1 and issues a command to the CPU 41 which is a control unit, whereby the CPU 41 reads the basic program and controls the drive unit 12 to administer the drug to the user.
The CPU 41 heats the thermistor constituting the heating temperature detector 17 by controlling the heating temperature detector 17. At this time, the power used for heating is, for example, about 1 mW to 5 mW.
The heating temperature detector 17 and the temperature detector 18 measure the resistance value of the thermistor to detect the temperature of the detection tube 13B at the position where the heating temperature detector 17 and the temperature detector 18 are provided, respectively. The signal SU and the downstream temperature detection signal SL are sent to the CPU 41.
The CPU 41 acquires the temperature detected by the heating temperature detector 17 by receiving the upstream temperature detection signal SU from the heating temperature detector 17.
Further, the CPU 41 receives the downstream temperature detection signal SL from the temperature detector 18 to acquire the temperature detected by the temperature detector 18.
In practice, the CPU 41 controls the drive unit 12 to move the piston 11 from the most retracted position to the most pushed position over 0.5 seconds once in 6 minutes in the basal mode to perform the pushing operation.
The CPU 41 acquires the upstream temperature detection signal SU and the downstream temperature detection signal SL from the heating temperature detector 17 and the temperature detector 18 from about 10 seconds before the pushing operation of the piston 11 to about 5 seconds later, respectively.
In the present embodiment, the CPU 41 starts obtaining the upstream temperature detection signal SU and the downstream temperature detection signal SL from the heating temperature detector 17 and the temperature detector 18 (that is, starts temperature measurement), and at the same time, the heating temperature. The detector 17 is heated and the acquisition of the upstream temperature detection signal SU and the downstream temperature detection signal SL is completed (that is, the temperature measurement is ended), and at the same time, the heating of the heating temperature detector 17 is ended.
[1-4. Temperature detection pattern]
In the flow path, when the piston 11 performs the pushing-in operation, various states such as a state in which the chemical liquid normally flows, a state in which bubbles are mixed, and a state in which the liquid is blocked can occur. Below, the temperature detection pattern which shows the characteristic curve of the upstream temperature detection signal SU and the downstream temperature detection signal SL in such various states is demonstrated with the state of a flow path.
[1-4-1. Temperature detection pattern of chemical flow state]
A temperature detection pattern PT1 shown in FIG. 6 is a temperature detection pattern in a chemical solution flow state that is a normal state in which bubbles are not mixed in the flow path and no blockage occurs.
In the temperature detection pattern PT1, the horizontal axis indicates the number of seconds from the start of temperature measurement, and the vertical axis indicates the temperature (degrees). Further, the piston 11 performs the pushing operation at a time point 10 seconds after the start of measurement, and the same applies to the temperature detection pattern according to the present embodiment thereafter.
The CPU 41 heats the heating temperature detector 17 to increase the upstream temperature detection signal SU. However, when the temperature rises to some extent, heat is released from the heating temperature detector 17 and the location heated by the heating temperature detector 17. Even if heating is continued due to the balance between the heating by the heating temperature detector 17 and the heating, the temperature does not rise, and the upstream temperature detection signal SU is in an equilibrium state where the predetermined temperature is maintained (temperature stable state).
Further, the CPU 41 prevents the influence of the excessive temperature rise on the chemical liquid MS. When the CPU 41 reaches a predetermined temperature, the CPU 41 sets the heating temperature detector 17 so that the upstream temperature detection signal SU maintains the predetermined temperature (temperature stable state). It is also possible to control.
In the temperature detection pattern PT1, when the heating temperature detector 17 starts the heating operation simultaneously with the start of temperature measurement, the chemical liquid MS inside the detection tube 13B in the vicinity of the heating temperature detector 17 is gradually heated toward the temperature stable state. It will be done. As a result, the temperature of the upstream temperature detection signal SU gradually increases, and a thermal marker MK is generated in the chemical liquid MS at the position where the heating temperature detector 17 is provided as shown in the state A of FIG.
Even immediately before the pushing operation of the piston 11 (at the time of 9 seconds), the temperature of the upstream temperature detection signal SU continues to rise and is not constant (hereinafter, this state is also referred to as a pre-temperature stabilization state).
On the other hand, since the thermal marker MK does not exist in the vicinity of the temperature detector 18, the temperature of the downstream temperature detection signal SL is almost the same as that at the start of measurement even immediately before the piston 11 is pushed.
When the pushing operation is performed by the piston 11 at the time point of 10 seconds, the thermal marker MK moves to the downstream side with the movement of the chemical liquid MS as in the state B of FIG.
At this time, since the unheated chemical liquid MS flows from the upstream side in the vicinity of the heating temperature detector 17 in the detection tube 13B, the temperature of the upstream temperature detection signal SU is 26.86 degrees as shown in the temperature detection pattern PT1. It suddenly drops by about 0.08 degrees from 26.79 degrees.
On the other hand, since the thermal marker MK passes in the vicinity of the temperature detector 18 in the detection tube 13B, the temperature of the downstream temperature detection signal SL is about 0.00 from 26.6 degrees to 26.7 degrees as shown in the temperature detection pattern PT1. It rises once.
At this time, since the chemical liquid MS is continuously heated by the heating temperature detector 17, as shown in the temperature detection pattern PT1, the temperature of the upstream temperature detection signal SU thereafter increases again toward the temperature stable state (state) C).
On the other hand, in the vicinity of the temperature detector 18 in the detection tube 13B, the thermal marker MK in the chemical liquid MS is thermally diffused, so that the temperature of the downstream temperature detection signal SL gradually decreases toward the normal temperature.
When the temperature measurement is completed (at the time of 15 seconds), the heating temperature detector 17 finishes the heating operation so that the chemical liquid MS is not further heated.
As described above, in the chemical liquid flow state before the temperature stabilization, the upstream temperature detection signal SU that has been gradually increased rapidly decreases immediately after the pushing operation of the piston 11 and then gradually increases, while the downstream temperature detection signal SU. A temperature change in which SL rapidly increases and gradually decreases is shown.
That is, immediately after the pushing operation of the piston 11, a temperature drop portion appears in the upstream temperature detection signal SU, and a temperature rise portion appears in the downstream temperature detection signal SL.
[1-4-2. Bubble detection temperature detection pattern]
In the temperature detection pattern PT2 shown in FIG. 7, when the piston 11 is pushed in, there is a possibility that the bubbles AR exist from the state in which the detection tube 13B in the position where the heating temperature detector 17 is provided is filled with the chemical MS. It is a temperature detection pattern that has changed to a certain state.
The temperature of the upstream temperature detection signal SU gradually increases from the temperature measurement start time. Thereby, as shown in the state A of FIG. 7B, the chemical liquid MS in the vicinity of the heating temperature detector 17 is heated in the flow path portion 13 immediately before the pushing operation of the piston 11 in the temperature detection pattern PT2 (at 9 seconds). Thus, the thermal marker MK is generated.
At this time, bubbles AR are mixed in the upstream portion of the heating temperature detector 17. In addition, an unheated chemical liquid MS exists on the upstream side of the thermal marker MK.
When the pushing operation is performed by the piston 11 at the time point of 10 seconds, since the unheated chemical liquid MS passes through the vicinity of the heating temperature detector 17 in the detection tube 13B, the temperature of the upstream temperature detection signal SU is once from 26.9 degrees. Slightly decreases to 26.88 degrees (at 11 seconds). Thereafter, as in state B in FIG. 7B, the inside of the detection tube 13B at the position where the heating temperature detector 17 is provided becomes a bubble AR made of air, not a chemical liquid MS made of liquid.
Since the bubble AR has a lower thermal conductivity than the chemical liquid MS, the heat generated from the heating temperature detector 17 is less likely to be transmitted to the bubble AR compared to the chemical liquid MS.
For this reason, the temperature of the upstream temperature detection signal SU rises rapidly due to heat generated by the heating temperature detector 17 and not absorbed by the bubble AR. Thereafter, the upstream temperature detection signal SU rises again toward the temperature stable state at a temperature change rate substantially the same as that before the piston 11 is pushed.
On the other hand, the temperature of the downstream temperature detection signal SL rises rapidly in the same manner as the chemical solution flow state because the thermal marker MK passes through the detection tube 13B in the vicinity of the temperature detector 18, and then gradually toward the normal temperature by thermal diffusion. It will drop to.
As described above, in the bubble change state, there is a case where there is an unwarmed chemical liquid MS on the upstream side of the thermal marker MK depending on the mixing timing of the bubble AR with respect to the chemical liquid MS.
In such a case, the upstream temperature detection signal SU that has gradually increased slightly decreases immediately after the pushing operation of the piston 11, but then rapidly increases and gradually increases, while the downstream temperature detection signal SL does not flow in the chemical solution. Similar to the state, it shows a temperature change that rapidly increases and gradually decreases.
On the other hand, when the state changes to a state where bubbles may exist, there may be no unheated chemical MS on the upstream side of the thermal marker MK depending on the timing of mixing of the bubbles AR with the chemical MS.
In such a case, the upstream temperature detection signal SU is slightly different from the temperature detection pattern PT2 (FIG. 7), and immediately rises without a slight drop immediately after the push-in operation of the piston 11, while the downstream temperature detection signal SL is a chemical flow. Similar to the state, it shows a temperature change that rapidly increases and gradually decreases.
That is, immediately after the pushing-in operation of the piston 11, a temperature sudden rise portion appears in the upstream temperature detection signal SU, and a temperature rise portion appears in the downstream temperature detection signal SL.
[1-4-3. Temperature detection pattern when changed to a state where bubbles may exist]
In the temperature detection pattern PT3 shown in FIG. 8, after the state (temperature detection pattern PT2 (FIG. 7)) has changed to a state where there is a possibility that air bubbles exist, the piston 11 further performs a pushing operation so that the air bubbles on the upstream side. A state in which there is a possibility that there is a bubble in which AR moves to the downstream side and the inside of the detection tube 13B at the position where the heating temperature detector 17 is provided is a bubble AR before the piston 11 is pushed. It is a temperature detection pattern in the state changed to (2).
Since the inside of the detection tube 13B in the vicinity of the heating temperature detector 17 is a bubble AR at the start of temperature measurement, the heat generated by the heating temperature detector 17 is not transmitted to the bubble AR, and the temperature of the bubble AR is Although the temperature hardly rises, the temperature of the upstream temperature detection signal SU rises due to heat generated by the heating temperature detector 17 and not absorbed by the bubble AR (state A in FIG. 8B).
When the pushing operation is performed by the piston 11 at the time of 10 seconds (state B in FIG. 8B), since the bubble AR inside the detection tube 13B in the vicinity of the heating temperature detector 17 is not warmed, the upstream temperature detection signal SU is The temperature rises toward the temperature stable state at a temperature change rate substantially the same as that before the pushing operation of the piston 11 without a sudden temperature change.
On the other hand, the downstream temperature detection signal SL is a constant temperature without substantially changing the temperature before the push-in operation of the piston 11 because the unwarmed bubble AR is only moved from the upstream side.
Thus, even if the pushing operation of the piston 11 is performed in the bubble state where the bubble AR is located inside the detection tube 13B at the position where the heating temperature detector 17 is already provided before the pushing operation of the piston 11, The upstream temperature detection signal SU, which has been gradually rising, rises without undergoing a large temperature change, while the downstream temperature detection signal SL also does not undergo a large temperature change.
[1-4-4. Blocking temperature detection pattern]
A temperature detection pattern PT4 shown in FIG. 9 is a temperature detection pattern in a closed state in which the flow path is closed.
In the temperature detection pattern PT4, the heating temperature detector 17 starts the heating operation simultaneously with the start of temperature measurement, so that the chemical liquid MS inside the detection tube 13B in the vicinity of the heating temperature detector 17 is gradually heated toward the temperature stable state. It will be done. As a result, the temperature of the upstream temperature detection signal SU gradually increases, and a thermal marker MK is generated in the chemical liquid MS in the vicinity of the heating temperature detector 17 as shown in the state A of FIG. 9B.
On the other hand, since the thermal marker MK does not exist in the vicinity of the temperature detector 18, the temperature of the downstream temperature detection signal SL is almost the same as that at the start of measurement even immediately before the piston 11 is pushed.
When the pushing operation is performed by the piston 11 at the time of 10 seconds, the flow path is closed, and the chemical liquid MS does not move in the flow path portion 13, so the upstream temperature detection signal SU does not undergo a rapid temperature change, It rises toward a temperature stable state at a temperature change rate substantially the same as before the pushing operation of the piston 11.
On the other hand, since the thermal marker MK does not move from the upstream side, the downstream temperature detection signal SL has a constant temperature with almost no temperature change.
In this way, in the closed state where the flow path is closed, the upstream temperature detection signal SU that has gradually increased even if the piston 11 is pushed in, as in the bubble state described above, shows a large temperature change. On the other hand, the downstream temperature detection signal SL also does not change greatly.
[1-5. Blockage detection processing]
As described above, in the drug solution administration device 1, the puncture unit 5 is deformed by a user's body movement or the like, or the drug solution is denatured, so that the channels such as the puncture unit 5 and the channel unit 13 are blocked. There is a possibility that the drug solution cannot be accurately administered to the user.
Therefore, the CPU 41 executes a blockage detection process for detecting whether or not the puncture unit 5 or the flow channel unit 13 is blocked based on the temperature change of the upstream temperature detection signal SU and the downstream temperature detection signal SL, thereby blocking the flow channel. Is detected.
The CPU 41 develops a liquid feeding program loaded with the blockage detection algorithm stored in the ROM 42 in the RAM 43 and executes a blockage detection process. When executing the blockage detection process, the CPU 41 functions as a temperature measurement unit 51, a drive control unit 52, a flow path state determination unit 53, a flow path state storage unit 54, and a notification control unit 55, as shown in FIG.
In the drug solution administration device 1, after the drug solution storage unit 7 is filled with the drug solution from the outside via the injection unit 6, the affixing unit 4 is affixed to the user's skin and the puncture unit 5 is punctured to the user's skin. The dose and the administration rate are input via the interface unit 45.
CPU41 determines the time which performs pushing operation of piston 11 based on the inputted dosage and administration speed. Further, the temperature measurement unit 51 determines the time for starting the heating of the heating temperature detector 17. Specifically, the timing for starting heating of the heating temperature detector 17 is a preheating time T1 (for example, 10 seconds) before the time during which the piston 11 is pushed.
The temperature measuring unit 51 starts to acquire the upstream temperature detection signal SU and the downstream temperature detection signal SL from the heating temperature detector 17 and the temperature detector 18, respectively, and starts heating the heating temperature detector 17.
When a preheating time T1 (for example, 10 seconds) elapses after the temperature measurement unit 51 starts heating the heating temperature detector 17, the drive control unit 52 controls the drive unit 12, and the piston 11 via the drive unit 12 is controlled. Start pushing operation.
When the pushing operation starts, the piston 11 is in the most retracted position. However, if the piston 11 is not in the most retracted position, the piston 11 is moved to the most retracted position based on the control of the drive control unit 52. After that, the pushing operation may be started.
The flow path state determination unit 53 determines whether or not the closed state has occurred during the pushing operation of the piston 11 and there is no air bubble mixed in the flow path (chemical liquid flow state (FIG. 6)).
Specifically, in the upstream temperature detection signal SU acquired by the temperature measurement unit 51, the flow path state determination unit 53 exceeds the threshold value of 0.05 degrees within one second from the time when the piston 11 performs the pushing operation. It is detected whether or not a temperature drop portion exists.
Furthermore, in the downstream temperature detection signal SL acquired by the temperature measurement unit 51, the flow path state determination unit 53 has a temperature rise portion exceeding the threshold value of 0.05 degrees within one second from the time when the piston 11 performs the pushing operation. Whether or not exists is detected.
The flow path state determination unit 53, when there is a temperature decrease part that exceeds the threshold value in the upstream temperature detection signal SU and there is a temperature increase part that exceeds the threshold value in the downstream temperature detection signal SL, the puncture part 5 and the flow path part 13 No occlusion has occurred, and it is determined that this is a normal chemical fluid flow bear (FIG. 6).
As described above, the flow path state determination unit 53 detects a temperature change in the opposite direction such that the temperature of the upstream temperature detection signal SU suddenly increases and the downstream temperature detection signal SL rapidly decreases, thereby changing the environmental temperature or the like. Even if there is a disturbance, it is possible to accurately detect the chemical flow state.
When the flow path state determination unit 53 determines that the chemical liquid flow state is currently present, the flow path state storage unit 54 indicates that the flow path state is the chemical liquid flow state in the current pushing operation of the piston 11. Store state information.
On the other hand, the flow path state determination unit 53 is not present in the flow path when either the temperature decrease part exceeding the threshold value in the upstream temperature detection signal SU or the temperature increase part exceeding the threshold value in the downstream temperature detection signal SL does not exist. It is determined that there is a possibility that an occlusion has occurred or air bubbles are mixed in.
When it is determined that there is a possibility that the flow path is clogged or that air bubbles are mixed, the flow path state determination unit 53 determines that the air bubbles positioned upstream of the heating temperature detector 17 in the flow path unit 13 By moving the piston 11 to the position where the heating temperature detector 17 is provided, it is determined whether or not the bubble change state (FIG. 7) has been reached.
Specifically, as shown in the temperature detection pattern PT2 (FIG. 7), in the upstream temperature detection signal SU, the temperature at the piston pushing operation time is set to the temperature Ts and a predetermined a second (for example, 2 seconds) from the piston pushing operation time point. ) Assuming that the previous temperature is the temperature Tb, the expected temperature Texp, which is a temperature after a predetermined t seconds (for example, 2 seconds) from the piston pushing operation time point, is predicted by the equation (2).

That is, the predicted temperature Texp includes the slope (temperature change rate) of the temperature change for a predetermined a second before the piston pushing operation time, the predetermined number of seconds (t seconds) after the piston pushing operation time, and the temperature Ts during the piston pushing operation. Based on the above.
The flow path state determination unit 53 compares the measured temperature T of the upstream temperature detection signal SU after a predetermined t seconds from the piston pushing operation with the expected temperature Texp. When the value obtained by subtracting the predicted temperature Texp from the measured temperature T is equal to or greater than a predetermined threshold Tth (for example, 0.05 degrees), the flow path state determination unit 53 performs the piston pushing operation performed when the current temperature is being measured. Thus, it is determined that the content of the detection tube 13B at the position where the heating temperature detector 17 is provided has changed from a chemical solution to a bubble (a state in which there is a possibility that a bubble may exist).
When the flow path state determination unit 53 determines that the current state has changed to a state in which bubbles may be present, the flow path state storage unit 54 determines that the flow path state is in the current pushing operation of the piston 11. The flow path state information indicating that the state has changed to a state in which there is a possibility that bubbles may exist is stored.
Incidentally, like the temperature detection pattern PT2, the temperature of the upstream temperature detection signal SU may slightly decrease once after the piston pushing operation depending on the timing of mixing bubbles with respect to the movement of the chemical solution.
On the other hand, the flow path state determination unit 53 compares the measured temperature T of the upstream temperature detection signal SU 2 seconds after the piston pushing operation with the expected temperature Texp, so that the temporary temperature of the upstream temperature detection signal SU is Without being affected by the drop, it is possible to accurately detect a state that has changed to a state where bubbles may exist.
On the other hand, if the flow path state determination unit 53 does not determine that the current state has changed to a state in which bubbles may exist, this means that the temperature detection pattern in this temperature measurement is the case where bubbles are present. This means that it is either the temperature detection pattern PT3 (FIG. 8) or the temperature detection pattern PT4 in the closed state (FIG. 9).
As described above, the temperature detection pattern PT3 in the state where bubbles are present and the temperature detection pattern PT4 in the closed state have similar characteristic curves. For this reason, the flow path state determination unit 53 is in a state where bubbles are present or in a closed state based on only the temperature detection pattern at the time of the current temperature measurement among the repeated temperature measurements. It is difficult to determine whether there is.
Therefore, the flow path state determination unit 53 refers to the flow path state information stored in the flow path state storage unit 54 to confirm the flow path state at the previous temperature measurement.
By the way, when the bubble AR is located in the detection tube 13B at the position where the heating temperature detector 17 is provided, even if the heating temperature detector 17 generates heat, the heat is hardly transmitted to the bubble as described above. The outside of the detection tube 13B generates heat.
Even if the piston is pushed in this state and the bubbles in the flow path section 13 move downstream, the bubbles are not warmed. Therefore, the upstream temperature detection signal SU and the downstream temperature detection signal SL include Large temperature change does not occur.
For this reason, when there is a possibility that air bubbles may exist at the previous temperature measurement, this is because the temperature change portion does not exist in the upstream temperature detection signal SU at the current temperature measurement. Since the bubble detected at the time of measurement is the cause, it means that the bubble is present and the channel is not blocked.
When the flow path state determination unit 53 determines that a bubble is currently present, the flow path state storage unit 54 indicates that the flow path state is a state where a bubble is present in the current pushing operation of the piston 11. Is stored.
As described above, when it is determined that there is a possibility that a chemical fluid state or bubbles may exist during the current temperature measurement, the temperature measurement unit 51 determines whether the bolus mode is set via the interface unit 45 or not. Determine.
In addition, it was determined that neither the chemical solution flow state nor the state in which bubbles might exist was present at the time of the current temperature measurement, and it was determined that the previous temperature measurement was in a state in which bubbles might be present. Similarly, in this case, the temperature measurement unit 51 determines whether the bolus mode is set via the interface unit 45.
In the present embodiment, the time interval of the piston pushing operation in the bolus mode is set to about 3 to 5 seconds. For this reason, after the current piston pushing operation, the next piston pushing operation is performed at a time point before the time point when 10 seconds of the preheating time T1 elapses.
For this reason, when the bolus mode is set, the temperature measurement unit 51 continues heating the heating temperature detector 17 in preparation for temperature measurement in the next piston pushing operation.
On the other hand, when the next piston pushing operation is not scheduled within the preheating time T1 after the piston pushing operation is performed, the temperature measurement unit 51 finishes heating the heating temperature detector 17. The medicinal-solution administration device 1 can reduce power consumption by not heating the heating temperature detector 17 until immediately before the next piston pushing operation starts.
On the other hand, when the flow path state determination unit 53 determines that the flow path state at the previous temperature measurement is not a state where bubbles may exist and is not a state where bubbles do not exist, the flow path is blocked. This means that it is in a state (FIG. 9).
At this time, the drive control unit 52 stops the operation of the drive unit 12. The notification control unit 55 controls the notification unit 46 to notify the user through the notification unit 46 that the puncture unit 5 and the flow path unit 13 are closed.
[1-6. Blockage detection procedure]
Next, the procedure of the blockage detection process described above will be described with reference to the flowchart of routine RT1 shown in FIG. The CPU 41 starts heating the heating temperature detector 17 and starts acquiring the upstream temperature detection signal SU and the downstream temperature detection signal SL from the heating temperature detector 17 and the temperature detector 18, respectively (steps SP1 and SP2). .
When preheating time T1 (for example, 10 seconds) elapses from the start of heating (step SP3), the CPU 41 starts the pushing operation of the piston 11 via the drive unit 12 (step SP4).
Based on the acquired upstream temperature detection signal SU and downstream temperature detection signal SL (temperature detection pattern), the CPU 41 generates a chemical flow state (a temperature decrease portion occurs in the upstream temperature detection signal SU and a temperature increase portion occurs in the downstream temperature detection signal SL). (Steps SP5 and SP6).
When the CPU 41 determines that it is in the chemical liquid flow state (YES in step SP6), it stores the flow path state (step SP8), and starts to push the piston 11 within the preheating time T1 (for example, 10 seconds). It is determined whether or not there is (step SP12).
If the CPU 41 determines that there is a plan to start the pushing operation of the piston 11 within the preheating time T1 (YES in step SP12), the heating temperature detector 17 is continuously heated and the next pushing operation of the piston 11 is performed. Start (step SP13).
On the other hand, if the CPU 41 determines that there is no plan to start the pushing operation of the piston 11 within the preheating time T1 (NO in step SP12), the CPU 41 ends the heating of the heating temperature detector 17 (step SP14) and performs temperature measurement. The process ends (step SP15) and waits until the next temperature measurement starts.
By the way, when CPU41 determines with it not being a chemical | medical solution flow state (it is NO at step SP6), it is a state (the measured temperature T in the upstream temperature detection signal SU is more than threshold value Tth rather than the expected temperature Texp) in the presence of a bubble. (Step SP7).
When the CPU 41 determines that there is a possibility that air bubbles exist (YES in step SP7), the CPU 41 stores the flow path state (step SP8). Further, the CPU 41 determines whether or not there is a plan to start the pushing operation of the piston 11 within the preheating time T1 (step SP12), and performs the same processing as described above.
On the other hand, if the CPU 41 determines that there is no possibility that air bubbles exist (NO in step SP7), the upstream temperature detection signal SU has not changed significantly due to the pushing operation of the piston 11, and therefore air bubbles exist. This indicates that there is a possibility or a closed state, and when the piston 11 is pushed in, it is determined whether there is a bubble or a closed state (step SP9).
On the other hand, if the CPU 41 determines that the blockage state is in the blockage detection process (YES in step SP9), that is, if the upstream temperature detection signal SU has not changed significantly in the blockage detection process, the flow path is blocked. It means that it is because.
The CPU 41 stops the operation of the drive unit 12 and notifies the user that the flow path is closed (step SP10), ends the temperature measurement (step SP11), and ends the process.
[1-7. Operation and effect]
In the above-described configuration, the drug solution administration device 1 is configured such that the piston 11 slides inside the cylinder 14 connected at one end to the flow path unit 13 for sending the drug solution from the drug solution storage unit 7 in which the drug solution is stored to the user's body. The drug solution is delivered into the user's body by moving.
The drug solution administration device 1 starts the temperature measurement and simultaneously heats the heating temperature detector 17 and starts the pushing operation of the piston 11 after the preheating time T1 has elapsed.
When the chemical liquid administration device 1 determines that the flow path is in a chemical flow state or a state in which bubbles may exist when the pushing operation of the piston 11 is performed, the chemical liquid administration apparatus 1 determines that the flow path is not blocked. Next, the pushing operation of the piston 11 is performed.
Next, when the medicinal solution administration device 1 performs the pushing operation of the piston 11 and determines that there is a possibility that the flow channel is in a closed state, the medicinal solution administration device 1 does not perform the pushing operation of the next piston 11, Notify the user that it is blocked.
As a result, the drug solution administration device 1 can prevent the state of bubbles that do not affect the human body from being erroneously determined as a closed state and stop the pushing operation of the piston 11, and can continue the administration of the drug solution.
Moreover, the chemical | medical solution administration apparatus 1 can stop the pushing operation of the piston 11 immediately, without misjudging the obstruction | occlusion state in the pushing operation of the piston 11 this time as a bubble state.
Furthermore, the chemical administration device 1 heats the heating temperature detector 17 at the same time as starting the temperature measurement, and ends the heating at the same time as finishing the temperature measurement, that is, heating for a time shorter than the time interval of the repeated piston pushing operation. The temperature detector 17 was heated.
Thereby, compared with the case where the heating temperature detector 17 is always heated, the chemical solution administration device 1 can prevent wasteful power consumption and can reduce power consumption.
According to the above configuration, the drug administration device 1 detects the state of the flow path based on the temperature change of the upstream temperature detection signal SU and the downstream temperature detection signal SL every time the piston 11 is pushed, and the flow path is blocked. In the previous push-in operation of the piston 11, when the detection temperature is detected, the detection tube 13B at the position where the heating temperature detector 17 is provided is changed from a state in which the inside of the detection tube 13B is filled with a chemical solution to a state in which bubbles are present. When changed, the next pushing operation of the piston 11 is continued. Thereby, the drug solution administration device 1 can continue the drug solution administration without erroneously determining the state in which bubbles are mixed in the channel as a state in which the channel is blocked. Thus, the medicinal solution administration device 1 can further improve the usability.
<2. Second Embodiment>
[2-1. Blockage detection processing]
The drug solution administration device 101 according to the second embodiment executes a blockage detection process different from that of the drug solution administration device 1 according to the first embodiment, and other parts are the same as the drug solution administration device 1.
As shown in FIG. 12 in which the same reference numerals are assigned to corresponding parts to FIG. 10, when executing the blockage detection process, the CPU 141 performs the temperature measurement unit 51, the drive control unit 52, the flow path state determination unit 53, It functions as the storage unit 54, the notification control unit 55, and the closed state counting unit 56.
The functional configuration of the CPU according to the second embodiment is added with a blocking state counting unit 56 as compared with the functional configuration of the CPU according to the first embodiment (FIG. 10).
When the flow path state determination unit 53 determines that the flow path is blocked, the closed state counting unit 56 sets the number of closed states indicating the number of times the closed state is detected during temperature measurement from the initial value of 0. Increase by one.
In the temperature measurement performed each time the piston 11 is repeatedly pushed, if the flow path is determined to be closed, the closed state counter 56 increases the closed state count by one. When it is determined that the flow path is not in the closed state, the closed state counting unit 56 returns the closed state count to 0, which is the initial value. That is, when the closed state of the flow path is continuously generated, the closed state counting unit 56 increases the number of closed states by 1 for each temperature measurement.
When the number of closed states is smaller than the threshold value of 5 times, the drive control unit 52 continues the operation of the drive unit 12 without stopping even if the flow path is closed.
On the other hand, the drive control part 52 stops operation | movement of the drive part 12, when the obstruction | occlusion state frequency | count becomes 5 times or more which is a threshold value.
[2-2. Blockage detection procedure]
Next, the procedure of the blocking detection process will be described with reference to the flowchart of the routine RT2 shown in FIG. Routine RT2 has steps SP16 and SP17 added as compared to routine RT1 (FIG. 11). Steps SP1 to SP15 are the same as the routine RT1, and thus the description thereof is omitted.
When the CPU 41 determines that there is a possibility that air bubbles exist (YES in step SP7), the CPU 41 stores the flow path state (step SP8). Further, the CPU 41 determines whether or not there is a plan to start the pushing operation of the piston 11 within the preheating time T1 (step SP12), and performs the same processing as described above.
On the other hand, if the CPU 41 determines that the blockage state is in the blockage detection process (YES in step SP9), that is, if the upstream temperature detection signal SU has not changed significantly in the blockage detection process, the flow path is blocked. If the number of closed states is less than a threshold value (for example, 5 times) (NO in step SP17), the processing after step SP12 is performed.
On the other hand, if the number of closed states is equal to or greater than a threshold value (for example, 5 times) (YES in step SP17), the CPU 141 stops the operation of the drive unit 12 and notifies the user that the flow path is closed ( Step SP10), the temperature measurement is finished (step SP11), and the process is finished.
Thus, the chemical solution administration apparatus 101 does not immediately stop the operation of the piston 11 when it is determined to be in the closed state, but stops the operation of the piston 11 when it is determined to be in the closed state continuously several times.
As a result, the medicinal solution administration device 101 prevents the operation of the piston 11 from being stopped immediately when it is erroneously determined to be in the closed state due to some error, and when the closed state has occurred reliably. Only the operation of the piston 11 can be stopped, and the usability can be improved.
The drug solution administration device 201 according to the third embodiment executes a blockage detection process different from that of the drug solution administration device 1 according to the first embodiment, and the other parts are the same as the drug solution administration device 1.
In the present embodiment, the CPU 241 raises the temperature of the upstream temperature detection signal SU to a temperature stable state before the piston 11 is pushed in by heating the heating temperature detector 17 one minute before starting the temperature measurement. The temperature is maintained at a substantially constant temperature (hereinafter, this state is also referred to as a temperature stabilized state).
Further, the CPU 241 does not end the heating of the heating temperature detector 17 even after the temperature measurement is ended, and continues until the next temperature measurement.
[3-1. Temperature detection pattern]
[3-1-1. Temperature detection pattern of chemical flow state]
As shown in FIG. 14, in the temperature detection pattern PT11, the chemical liquid MS inside the detection tube 13B in the vicinity of the heating temperature detector 17 is sufficiently heated, and the upstream temperature detection signal SU is immediately before the pushing operation of the piston 11 (at 7 seconds). ) At a constant temperature.
When the pushing operation is performed by the piston 11 at the time of 8 seconds, the thermal marker MK moves to the downstream side, so that, as in the temperature detection pattern PT1 (FIG. 6), a temperature drop portion appears in the upstream temperature detection signal SU. In the downstream temperature detection signal SL, a temperature rise portion appears.
[3-1-2. Temperature detection pattern in the state of chemical fluid flow and the possibility of air bubbles]
A temperature detection pattern PT12 shown in FIG. 15 is a temperature detection pattern when the state changes to a state where bubbles may exist after the chemical solution flow state. In the temperature detection pattern PT12, the piston 11 is pushed once every 10 seconds and 18 seconds.
In the temperature detection pattern PT12, the chemical liquid MS in the detection tube 13B in the vicinity of the heating temperature detector 17 is sufficiently heated, and the upstream temperature detection signal SU is constant immediately before the first pushing operation of the piston 11 (at 9 seconds). As shown in the state A in FIG. 15B, a thermal marker MK is generated in the chemical liquid MS in the vicinity of the heating temperature detector 17. At this time, bubbles AR are mixed in the upstream portion of the heating temperature detector 17.
When the first pushing operation is performed by the piston 11 at the time point of 10 seconds, the thermal marker MK moves to the downstream side. Therefore, as with the temperature detection pattern PT11 (FIG. 14), the upstream temperature detection signal SU includes a temperature drop portion. On the other hand, a temperature rise portion appears in the downstream temperature detection signal SL.
Thereafter, the temperature of the upstream temperature detection signal SU gradually increases, and the temperature of the downstream temperature detection signal SL gradually decreases.
At this time, the air bubbles AR are carried to the upstream of the vicinity of the heating temperature detector 17 by the first pushing operation of the piston 11 into the flow path portion 13. In addition, as shown in the state B of FIG. 15B, the flow path portion 13 immediately before the second pushing operation of the piston 11 is heated in the vicinity of the heating temperature detector 17, and the thermal marker MK. Has been generated.
At this time, unlike the state A in FIG. 7B, there is no unheated chemical solution MS upstream of the portion where the thermal marker MK is formed. That is, the thermal marker MK is in direct contact with the bubble AR located on the upstream side without passing through the chemical liquid MS.
When a second pushing operation is performed by the piston 11 at 18 seconds, the inside of the detection tube 13B at the position where the heating temperature detector 17 is provided is not the chemical liquid MS, as in the state C of FIG. Since it becomes the bubble AR, the temperature of the upstream temperature detection signal SU rapidly rises due to heat that is not absorbed by the bubble AR, and then rises again at a temperature change rate almost the same as before the pushing operation of the piston 11.
On the other hand, the temperature of the downstream temperature detection signal SL rises to a normal temperature by thermal diffusion after the thermal marker MK rapidly rises in the same manner as the chemical fluid state because the thermal marker MK passes through the detection tube 13B at the position where the temperature detector 18 is provided. It gradually declines.
As described above, in the state where there is a possibility that bubbles exist, there may be no unwarmed chemical liquid MS on the upstream side of the thermal marker MK depending on the mixing timing of the bubble AR with respect to the chemical liquid MS.
In such a case, the upstream temperature detection signal SU rises rapidly without a slight drop immediately after the pushing operation of the piston 11, while the downstream temperature detection signal SL rises rapidly and gradually decreases in the same manner as the chemical fluid state. Indicates.
[3-1-3. Temperature detection pattern in the presence of air bubbles]
A temperature detection pattern PT13 illustrated in FIG. 16 is a temperature detection pattern in a bubble change state in which the bubbles AR are mixed in the flow path.
The temperature detection pattern PT13 is different in the timing of mixing the bubble AR with respect to the movement of the chemical liquid MS in the flow path unit 13 as compared with the second pushing operation of the piston 11 in the temperature detection pattern PT12.
In the temperature detection pattern PT13, the chemical liquid MS inside the detection tube 13B in the vicinity of the heating temperature detector 17 is sufficiently heated, and the upstream temperature detection signal SU becomes a constant temperature immediately before the pushing operation of the piston 11 (at 9 seconds), As shown in state A in FIG. 16B, a thermal marker MK is generated in the chemical liquid MS in the vicinity of the heating temperature detector 17.
Further, similarly to the temperature detection pattern PT2 (FIG. 7), an unheated chemical liquid MS exists on the upstream side of the thermal marker MK.
When the pushing operation is performed by the piston 11 at the time point of 10 seconds, since the unheated chemical liquid MS passes through the detection tube 13B at the position where the heating temperature detector 17 is provided, the temperature of the upstream temperature detection signal SU is slightly slightly once. descend. Thereafter, similarly to the temperature detection pattern PT2, the temperature of the upstream temperature detection signal SU rises rapidly, and becomes a constant temperature as before the pushing operation of the piston 11.
As described above, in a state where there is a possibility that air bubbles exist, there may be an unwarmed chemical liquid MS on the upstream side of the thermal marker MK depending on the mixing timing of the bubble AR with respect to the chemical liquid MS.
In such a case, the upstream temperature detection signal SU, which has been at a constant temperature, slightly decreases immediately after the pushing operation of the piston 11, but then rapidly increases, while the downstream temperature detection signal SL is similar to the chemical flow state. It shows a temperature change that suddenly increases and gradually decreases.
That is, immediately after the pushing-in operation of the piston 11, a temperature sudden rise portion appears in the upstream temperature detection signal SU, and a temperature rise portion appears in the downstream temperature detection signal SL.
[3-1-4. Bubble temperature detection pattern]
In the temperature detection pattern PT14 shown in FIG. 17, after the state in which bubbles may exist (temperature detection pattern PT13 (FIG. 16)), the piston 11 further performs a pushing operation so that the upstream side bubbles AR are on the downstream side. This is a temperature detection pattern in a bubble state in which the inside of the detection tube 13B at the position where the heating temperature detector 17 is provided at the time before the pushing operation of the piston 11 is filled with the bubble AR.
In the temperature detection pattern PT14, since the inside of the detection tube 13B at the position where the heating temperature detector 17 is provided is a bubble AR, the upstream temperature detection signal SU is a piston due to heat generated by the heating temperature detector 17 that is not absorbed by the bubble AR. 11 immediately before the pushing operation (at 9 seconds), the temperature is constant.
When the pushing operation is performed by the piston 11 at the time point of 10 seconds, the upstream temperature detection signal SU and the downstream temperature detection signal SL have a constant temperature without a sudden temperature change, similarly to the temperature detection pattern PT3 (FIG. 8). keep.
[3-1-5. Blocking temperature detection pattern]
A temperature detection pattern PT15 shown in FIG. 18 is a temperature detection pattern in a closed state in which the flow path is closed.
In the temperature detection pattern PT15, the chemical liquid MS inside the detection tube 13B in the vicinity of the heating temperature detector 17 is sufficiently heated, and the upstream temperature detection signal SU becomes a constant temperature immediately before the piston 11 is pushed (at 9 seconds). .
When the pushing operation is performed by the piston 11 at the time point of 10 seconds, the upstream temperature detection signal SU and the downstream temperature detection signal SL have a constant temperature without a sudden temperature change, similarly to the temperature detection pattern PT4 (FIG. 9). keep.
As described above, also in the third embodiment, as in the first embodiment, the temperature detection patterns in the bubble state and the closed state have substantially the same characteristic curves.
[3-2. Blockage detection processing]
The medicinal-solution administration device 201 according to the third embodiment performs a blockage detection process similar to that of the medicinal-solution administration device 1 according to the first embodiment, so that the flow path is based on the above-described temperature detection patterns PT11 to PT15. It is determined whether the flow path state is a chemical solution flow state, a state where bubbles may be present, a state where bubbles are present, or a closed state.
As described above, the medicinal solution administration device 201 can perform temperature measurement stably by performing temperature measurement in the state after temperature stabilization, compared to the case of performing temperature measurement in the state before temperature stabilization.
<4. Other embodiments>
In the above-described embodiment, the case where the heating temperature detector 17 is composed of a thermistor has been described. The present invention is not limited to this, and may be composed of various elements that can simultaneously perform heating and temperature detection.
Further, in the above-described embodiment, the case where the temperature detector 18 is constituted by a thermistor has been described. The present invention is not limited to this, and may be composed of various elements capable of detecting temperature.
Further, in the above-described embodiment, heating and temperature detection are performed by the heating temperature detector 17, but the present invention is not limited to this, and heating and temperature detection may be performed by separate elements. . In that case, it is desirable that the element that performs heating and the element that performs temperature detection be disposed close to each other.
Furthermore, in the above-described embodiment, the case where the flow path state is determined based on the upstream temperature detection signal SU and the downstream temperature detection signal SL has been described. The present invention is not limited to this, and the flow path state may be determined based only on the upstream temperature detection signal SU.
When determining whether or not the flow path is in a chemical flow state, it is possible to accurately determine the flow path state by detecting both the temperature drop portion of the upstream temperature detection signal SU and the temperature rise portion of the downstream temperature detection signal SL. In the case where it is based only on the temperature change of the upstream temperature detection signal SU, the processing can be simplified.
In the above-described embodiment, the case where the puncture unit 5 and the flow channel unit 13 are separately configured has been described. However, the flow channel through which the chemical solution flows from the chemical solution storage unit 7 to the outside is integrally formed as the flow channel unit. You may do it.
Furthermore, in the above-described embodiment, the CPU 41 as the determination unit, the chemical solution storage unit 7 as the chemical solution storage unit, the flow channel unit 13 as the flow channel unit, the cylinder 14 as the cylinder, and the piston 11 as the piston. And a heating temperature detector 17 as a heater, a heating temperature detector 17 and a temperature detector 18 as temperature detectors, and a flow path state determination unit 53 as a flow path state determination unit. The case where the chemical liquid administration apparatuses 1, 101, and 201 are configured has been described.
The present invention is not limited to this, and includes a determination unit having various configurations, a chemical storage unit, a flow channel unit, a cylinder, a piston, a heater, a temperature detector, and a flow channel state determination unit. Alternatively, a liquid administration device may be configured.

The present invention can be applied to the medical field, for example.

DESCRIPTION OF SYMBOLS 1,101,201 ... Chemical solution administration apparatus, 2 ... Lower housing | casing part, 3 ... Upper housing | casing part, 4 ... Pasting part, 5 ... Puncture part, 6 ... Injection | pouring part, 7 ... Chemical solution storage , 8 ... Substrate part, 9, 309 ... Delivery part, 11 ... Piston, 12 ... Drive part, 13 ... Flow path part, 14 ... Cylinder, 15 ... One-way valve, 16 ... Temperature Detection unit, 17 ... heating temperature detector, 18 ... temperature detector, 41 ... CPU, 42 ... ROM, 43 ... RAM, 44 ... power supply unit, 45 ... interface unit, 46 ... notification unit , 47 …… Bus, 51 …… Temperature measurement unit, 52 …… Drive control unit, 53 …… Flow path state determination unit, 54 …… Flow path state storage unit, 55 …… Notification control unit, 56 …… Blocking state Counting unit, MS ... chemical solution, AR ... bubble, MK ... thermal marker

Claims

A portable drug administration device that is held by a user and administers the drug into the user's body,
A determination unit;
A chemical storage section for storing the chemical liquid;
A flow path section that forms a flow path for feeding a chemical liquid from the chemical liquid storage section to the user's body; and
A cylinder having one end connected to the flow path portion;
A piston that slides inside the cylinder and feeds the drug solution into the body of the user through the flow path portion by a pushing operation of moving from the opposite side of the one end to the one end side in the cylinder;
A heater that is provided downstream of the cylinder in the flow path section and heats the flow path section;
A temperature detector provided in the vicinity of the heating element or on the downstream side of the flow path section, and detects the temperature of the flow path section and sends it as a temperature detection signal;
Each time the piston is pushed in, it is determined whether there is a possibility that air bubbles are present in the flow path portion based on a temperature change of the temperature detection signal, and further, it is determined whether or not it is in a closed state. A flow path state determination unit;
A medicinal-solution administration device comprising:
When the flow path portion is closed, it further has a closed state counting unit that counts the number of times the closed state has occurred each time the piston is pushed in,
The flow channel state determination unit determines that the flow channel unit is blocked when the number of occurrences of the blocked state is equal to or greater than a predetermined number of times set in advance. The chemical solution administration device described.
The temperature detector is composed of an upstream temperature detector provided in the vicinity of the heater and a downstream temperature detector provided on the downstream side of the flow path section from the upstream temperature detector,
The upstream temperature detector detects the temperature of the flow path part and sends it to the flow path state determination part as an upstream temperature detection signal,
The downstream temperature detector detects the temperature of the flow path part and sends it to the flow path state determination part as a downstream temperature detection signal,
The flow path state determination unit may block the flow path unit based on temperature changes in opposite directions of the upstream temperature detection signal and the downstream temperature detection signal during the pushing operation of the piston. The medicinal-solution administration device according to claim 1 that detects whether or not it exists.
The medicinal-solution administration device according to claim 1, wherein the heating element heats the flow path part for a time shorter than a time interval of the piston pushing operation that is repeatedly performed.
In a portable drug solution administration device for holding a drug solution in a user's body, the flow path for feeding the drug solution from the drug solution storage unit for storing the drug solution to the user's body is provided. The chemical liquid in the flow path portion to be formed is heated by a heating element, and the temperature of the flow path section is detected by a temperature detector provided in the vicinity of the heating element or on the downstream side of the flow path section. A blockage detection method for detecting blockage of a part,
The inside of the user's body is slid inside the cylinder whose one end is connected to the flow path portion and moves from the opposite side of the one end to the one end side in the cylinder through the flow path portion. Each time the piston that feeds liquid is pushed in, the temperature detector provided on the downstream side of the flow channel portion from the cylinder detects the temperature change of the temperature detection signal that detects the temperature of the flow channel portion. Determining whether there is a possibility that air bubbles are present in the flow path part based on the state in the flow path part; and
And a step of determining whether or not it is in a closed state.