Pump assembly, drug injection device comprising same, and method for detecting flow path blockage

Abstract

The pump assembly according to the present invention comprises: an electro-osmotic pump which comprises a monitoring chamber that is subject to pressure measurement, and which draws in and discharges a fluid being transferred by electrochemically and alternately generating positive pressure and negative pressure; and a pressure monitoring unit which is coupled to one side of the monitoring chamber and measures the internal pressure of the monitoring chamber.

Description

Pump assembly, drug delivery device including same, and method for detecting blockage of urea

[0001] The present invention relates to a pump assembly, a drug injection device including the same, and a method for detecting a blockage of a flow path using the drug injection device.

[0002] Depending on the type, purpose, and method of treatment, medications can be administered orally, subcutaneously, or intravenously. Drug infusion devices utilizing drug pumps can automatically inject medication into the body at the desired rate and dose at the required time. Therefore, drug infusion devices utilizing drug pumps can be utilized in a variety of ways, not just in hospitals or patients' daily lives.

[0003] An insulin pump, commonly called an insulin injector, is a medical device that acts like a pancreas to control blood sugar levels by supplying insulin from outside the body at a set time precisely for diabetic patients who do not secrete insulin or secrete only a small amount.

[0004] These insulin pumps are used by patients with insulin-dependent diabetes, and can deliver medication continuously 24 hours a day while attached to the patient. Because insulin injectors require patients to administer medication periodically over long periods of time, active technology development is underway to miniaturize and automate insulin injectors for greater user convenience.

[0005] However, as insulin injectors become smaller and more automated, it becomes increasingly difficult to ensure their operational stability. This is largely due to back pressure at the tip of the injector, which is caused by various reactions between the drug and the biological fluid. This back pressure is particularly severe when the amount of drug being injected is small or slow. Back pressure-induced back pressure increases the internal pressure of the insulin injector, and the occurrence of back pressure can be monitored by measuring the back pressure.

[0006] Therefore, a device is required that can monitor the clogging of an insulin injector, continuously inject the drug to the patient, and stably inject an accurate amount of the drug.

[0007] The present invention, in order to solve the above-mentioned problem, has as a technical object a pump assembly including a pressure monitoring unit that more accurately measures the internal pressure of an electroosmotic pump.

[0008] In addition, the technical task is to provide a drug injection device including a pump assembly capable of measuring internal pressure.

[0009] However, the technical tasks that this embodiment seeks to accomplish are not limited to the technical tasks described above, and other technical tasks may exist.

[0010] As a technical means for solving the above-described technical problem, a pump assembly according to the present invention comprises: an electroosmotic pump including a monitoring chamber as a pressure measurement target, and generating positive and negative pressures electrochemically alternately to suck and discharge a fluid to be transported; and a pressure monitoring unit coupled to one side of the monitoring chamber and measuring the internal pressure of the monitoring chamber.

[0011] According to the problem solving means of the present invention described above, the internal pressure can be adjusted according to the external pressure, and the pressure for inhaling and discharging the drug can be adjusted according to the internal pressure by a pressure monitoring unit that measures the internal pressure, thereby preventing an operation error due to the difference between the external and internal pressures.

[0012] FIG. 1 is a front perspective view of a drug injection device according to one embodiment of the present invention.

[0013] FIG. 2 is a rear perspective view of a drug injection device according to one embodiment of the present invention.

[0014] Figure 3 is an internal plan view of the drug injection device illustrated in Figure 1.

[0015] Figure 4 is a perspective view of the drug storage unit illustrated in Figure 3.

[0016] Figure 5 is a perspective view of the pump assembly illustrated in Figure 3.

[0017] Fig. 6 is a plan view showing the joint structure of the pump assembly illustrated in Fig. 5.

[0018] Figure 7 is a block diagram schematically showing the configuration of the electroosmotic pump illustrated in Figure 5.

[0019] Fig. 8 is a conceptual diagram schematically showing the configuration of the driving unit illustrated in Fig. 7.

[0020] Figure 9 is an example diagram schematically showing the operation of the driving unit illustrated in Figure 8.

[0021] Fig. 10 is a plan view showing the combined structure of the pressure monitoring unit illustrated in Fig. 6.

[0022] Figure 11 is a cross-sectional view showing the connection part of the electroosmotic pump and the pressure monitoring unit.

[0023] Figure 12 is a perspective view of the monitoring chamber frame illustrated in Figure 10.

[0024] Fig. 13 is a top perspective view of the pressure sensor frame illustrated in Fig. 10.

[0025] Fig. 14 is a rear perspective view of the pressure sensor frame illustrated in Fig. 13.

[0026] Fig. 15 is a cross-sectional view taken along the cutting line A-A' shown in Fig. 10.

[0027] Figure 16 is a block diagram schematically showing a drug injection device according to one embodiment of the present invention.

[0028] Figure 17 is a flowchart for explaining a method for detecting insertion tube blockage according to one embodiment of the present invention.

[0029] Fig. 18 is a flowchart for explaining one embodiment of a step for determining whether the euro illustrated in Fig. 17 is blocked.

[0030] FIG. 19 is a flowchart for explaining another embodiment of the step of determining whether the euro illustrated in FIG. 17 is blocked.

[0031] Hereinafter, the present invention will be described in detail with reference to the attached drawings. However, the present invention can be implemented in various different forms and is not limited to the embodiments described herein. In addition, the attached drawings are only intended to facilitate easy understanding of the embodiments disclosed in the present specification, and the technical ideas disclosed in the present specification are not limited by the attached drawings. In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and the size, shape, and shape of each component shown in the drawings can be variously modified. The same / similar drawing reference numerals are assigned to the same / similar parts throughout the specification.

[0032] The suffixes "assembly" and "part" used in the following description for components are assigned or used interchangeably solely for the convenience of writing the specification, and do not in themselves have distinct meanings or roles. Furthermore, in describing the embodiments disclosed herein, detailed descriptions of related known technologies have been omitted if they are deemed to obscure the gist of the embodiments disclosed herein.

[0033] Throughout the specification, when a part is said to be "connected (connected, in contact with, or coupled)" to another part, this includes not only cases where it is "directly connected (connected, in contact with, or coupled)" but also cases where it is "indirectly connected (connected, in contact with, or coupled)" with another member in between. Furthermore, when a part is said to "include (have or provide)" a certain component, this does not mean that it excludes other components, but rather that it may "include (have or provide)" other components, unless otherwise specifically stated.

[0034] As used herein, ordinal terms such as "first," "second," etc., are used solely to distinguish one component from another and do not limit the order or relationship of the components. For example, the first component of the present invention may be referred to as the "second component," and similarly, the second component may also be referred to as the "first component."

[0035] FIG. 1 is a front perspective view of a drug injection device according to an embodiment of the present invention, FIG. 2 is a rear perspective view of a drug injection device according to an embodiment of the present invention, and FIG. 3 is an exploded perspective view of the housing illustrated in FIG. 1.

[0036] Referring to FIGS. 1 to 3, a patch-type drug injection device (10) according to one embodiment of the present invention is described. The patch-type drug injection device (10) includes a housing (100) and components arranged inside the housing (100).

[0037] The housing (100) includes a cover portion (110) and a contact surface (120), and a mounting space is formed between the cover portion (110) and the contact surface (120). The cover portion (110) has rounded corners so that the patch-type drug injection device (10) can remain attached. The contact surface (120) is configured to be attached to an injection target, and an outlet (121) for withdrawing the insertion tube to the outside is formed.

[0038] The mounting space is divided into a central region (130) and first to third regions (140, 150, 160), and the first to third regions (140, 150, 160) are formed in a form that surrounds the central region (130). In particular, the mounting space within the housing (100) is divided into first to third regions (140, 150, 160) that extend in a direction perpendicular to the insertion direction of the insertion tube, and the central region (130). Then, major components are combined in each region. In a typical case, the PCB circuit part is first arranged over the entire or most of the plane of the device, and then the drug storage part or pump, etc. are arranged on top of it, so there is a problem that the thickness of the device is formed thick. However, in the patch-type drug injection device (10) of the present invention, in order to make the thickness thin, the area where each component overlaps with each other is minimized.

[0039] The components include a drug storage unit (200), a pump assembly (300), an injection assembly (400), and a circuit unit (500), and may be arranged in the central region (130) and the first to third regions (140, 150, 160) described above. For example, the drug storage unit (200) may be arranged in the first region (140), the pump assembly (300) in the second region (150), the circuit unit (500) in the third region (160), and the injection assembly (400) in the central region (130). Accordingly, the drug storage unit (200), the pump assembly (300), and the circuit unit (500) may be arranged in a manner that surrounds the injection assembly (400).

[0040] In this way, the injection assembly (400) including the insertion tube is positioned in the central region (130), so that the patch-type drug injection device (10) can remain connected to the user without the insertion tube coming off even when there is a change such as shaking due to the user's movement.

[0041] Next, the drug storage unit (200), pump assembly (300), injection assembly (400), and circuit unit (500) will be described in detail.

[0042] FIG. 4 is a plan view of the drug storage unit illustrated in FIG. 3. Referring to FIG. 4, the drug storage unit (200) is described. The drug storage unit (200) stores a drug to be injected, and its thickness changes depending on the amount of the drug to be injected. The drug storage unit (200) may be provided as a flat pouch bag made of a polymer material. A flange unit (210) may be formed around the drug storage unit (200) in which both sides constituting the drug storage unit (200) are joined to a predetermined width. The flange unit (210) may limit the drug storage unit (200) from expanding around the drug.

[0043] The drug storage unit (200) is composed of a release paper, and the inside and outside of the drug storage unit (200) are made of materials having different melting temperatures, and the melting temperature of the inside material is lower than the melting temperature of the outside material. The drug storage unit (200) is made by applying heat to a predetermined temperature at which the inside material melts to form a flange portion (210). When heat is applied to the side, the inside materials are attached to each other and finished, and the lower side is folded into a W shape and heat is applied. At this time, the inside materials are attached to each other and the outside materials are not attached to each other, so the flange portion (210) is formed.

[0044] In addition, the drug storage unit (200) is coupled with a drug entrance (220) through which drugs are introduced, so that drugs are introduced into the drug storage unit (200) or drugs stored in the drug storage unit (200) are discharged to the outside.

[0045] Figure 5 is a perspective view of the pump assembly illustrated in Figure 3, and Figure 6 is a plan view showing the joint structure of the pump assembly illustrated in Figure 5.

[0046] Referring to FIGS. 5 and 6, the pump assembly (300) is described. The pump assembly (300) serves as a driving means in the drug injection device (10), and operates as a pump that sucks in a drug from the drug storage unit (200) and discharges it to the outside.

[0047] The pump assembly (300) includes an electroosmotic pump (310) and a pressure monitoring unit (320). The electroosmotic pump (310) includes a monitoring chamber that is a pressure measurement target, and electrochemically generates positive and negative pressures alternately to draw in a drug from a drug storage unit (200) and discharge the drawn drug into an injection assembly (400).

[0048] The pressure monitoring unit (320) measures the pressure inside the monitoring chamber, thereby detecting a blockage in the flow path of the pump assembly (300) or the drug injection device (10). That is, the pressure monitoring unit (320) detects a case where the pressure abnormally increases due to a blockage in the flow path.

[0049] In addition, the pressure monitoring unit (320) of the present invention minimizes the pressure difference between the outside and inside of the pump assembly (300) for more accurate pressure measurement, and for this purpose, changes the internal pressure according to changes in the outside pressure.

[0050] Next, the electroosmotic pump (310) and the pressure monitoring unit (320) will be described in detail.

[0051] Fig. 7 is a block diagram schematically showing the configuration of the electroosmotic pump (310) illustrated in Fig. 6, Fig. 8 is a block diagram schematically showing the configuration of the driving unit illustrated in Fig. 7, and Fig. 9 is an exemplary diagram schematically showing the operation of the driving unit illustrated in Fig. 8.

[0052] Referring to FIGS. 7 and 8, the electroosmotic pump (310) will be described in detail. The electroosmotic pump (310) includes a driving unit (311), a transport chamber (312), a suction unit (313, 314), and a discharge unit (315, 316). The driving unit (311) is electrochemically driven by a control signal to generate positive pressure and negative pressure, and sucks and discharges a drug according to the positive pressure and negative pressure. The transport chamber (312) receives a drug sucked from the drug storage unit (200) by the driving unit (311). In addition, the suction unit (313) transfers the drug to the transport chamber, and the discharge unit (314) outputs the drug from the transport chamber (312). Here, the drug is a drug that must be injected into a specific patient, and an example of this is insulin injected into a diabetic patient.

[0053] Referring to FIGS. 8 and 9, the driving unit (311) is a pump that uses the movement of fluid by the electroosmotic phenomenon that occurs when voltage or current is applied using electrodes at both ends of a pressure generating unit (membrane, 311a). The driving unit (311) may include a power source (311d) that applies voltage or current to a membrane (311a) and a first electrode (311b) and a second electrode (311c) arranged on both sides of the membrane (311a), a first isolation unit (first diaphragm) 311e) for moving the fluid, and a second isolation unit (second diaphragm) (311f). Each diaphragm (311e, 311f) is provided on one side and the other side of the membrane (311a) and changes shape by the movement of the pumping solution as positive and negative pressures are alternately generated. For example, the first diaphragm (311e) and the second diaphragm (311f) transfer the negative and positive pressures generated by the operation of the membrane (311a) to the fluid to be transported. More specifically, when negative pressure is generated, at least a part of the first diaphragm (311e) and the second diaphragm (311f) moves backward (when moving in the ① direction), and the fluid to be transported is sucked into the transport chamber (312). Conversely, when positive pressure is generated, at least a part of the first diaphragm (311e) and the second diaphragm (311f) moves forward (when moving in the ② direction), and the fluid to be transported is discharged from the transport chamber (312).

[0054] The material of the membrane (311a) is generally silica, glass, etc., and when these are immersed in an aqueous solution, their surfaces become negatively charged. The membrane (311a) has numerous paths through which fluids can pass, and when one of these is enlarged, the surface of the fluid passage with a negative charge (bound anion) can be in a state where the charge is balanced by cations with a movable (+) charge. In this state, when a (+) voltage is applied to the first electrode (311b) and a (-) voltage is applied to the second electrode (311c), a negative pressure is generated, and the fluid inside the driving unit (311) moves in direction ① due to this negative pressure. At this time, the drug is inhaled through the inhalation path (314) and flows into the transport chamber (312) through the inhalation valve (313). At this time, the discharge valve (315) is closed so that negative pressure is not transmitted to the discharge path (316). Conversely, when a (-) voltage is applied to the first electrode (311b) and a (+) voltage is applied to the second electrode (311c), a positive pressure in the opposite direction is generated by a reversible electrochemical reaction. The fluid inside the driving unit (311) moves in direction ② due to this positive pressure. At this time, the drug stored in the transport chamber (312) is injected into the subject through the discharge valve (315) and the discharge path (316). At this time, the suction valve (313) is closed so that positive pressure is not transmitted to the suction path (314).

[0055] This phenomenon is called electroosmosis, and a pump that utilizes this principle is an electroosmotic pump (310). Since the pump assembly (300) of the present invention uses an electroosmotic pump (310) as a driving means, it can be manufactured thinner than other driving means such as an electric motor. Furthermore, the overall thickness of the patch-type drug injection device (10) that uses the pump assembly (300) as a driving means can be manufactured thinner, so that it can be more stably bonded to the skin.

[0056] Fig. 10 is a plan view showing the joint structure of the pressure monitoring unit, and Fig. 11 is a cross-sectional view showing the joint portion of the electroosmotic pump and the pressure monitoring unit. In addition, Fig. 12 is a top perspective view of the monitoring chamber frame shown in Fig. 10, Fig. 13 is a top perspective view of the pressure sensor frame shown in Fig. 10, Fig. 14 is a rear perspective view of the pressure sensor frame shown in Fig. 10, and Fig. 15 is a cross-sectional view taken along the cutting line A-A' of Fig. 10.

[0057] Referring to FIGS. 10 to 15, the pressure monitoring unit (320) is coupled to an electro-osmotic pump (310) to measure the internal pressure of the electro-osmotic pump (310). The pressure monitoring unit (320) is coupled to the driving unit (311) of the electro-osmotic pump (310), and specifically, is coupled to a second isolation unit (second diaphragm, 311f) on the opposite side of the pressure generating unit (membrane, 311a) of the driving unit (311). By coupling with the second isolation unit (311f), the pressure monitoring unit (320) closes the monitoring chamber (321a), which is an open space on one side of the second isolation unit (311f), and measures the internal pressure of the monitoring chamber (321a).

[0058] To perform this role, the pressure monitoring unit (320) includes a monitoring chamber frame (321) and a pressure sensor frame (322).

[0059] Referring to FIGS. 11 and 12, the monitoring chamber frame (321) is coupled to the second isolation section (311f) to close the monitoring chamber (321a), which is a space where pressure is measured, and a communication space (321b) is formed to expose the pressure sensor (322a) to be described later to the monitoring chamber (321a).

[0060] The pressure sensor frame (322) is laminated on one side of the monitoring chamber frame (321) and includes a pressure sensor (322a) that measures the pressure of the monitoring chamber (321a) through the communication space (321b) of the monitoring chamber frame (321). The pressure sensor (322a) is coupled to the lower surface of the pressure sensor frame (322) and is exposed to the monitoring chamber (221a) through the communication space (321b) of the monitoring chamber frame (321). The shape of the communication space (321b) can be formed to correspond to the shape of the pressure sensor (322a), thereby exposing the pressure sensor (322a) to the monitoring chamber (321a) while minimizing the area or volume of the communication space (321b), thereby minimizing wasted space.

[0061] In addition, the pressure monitoring unit (320) may further include a pressure delay unit (323) that communicates with the monitoring chamber (321a), causes external pressure to act on the internal pressure of the monitoring chamber (321a), and delays the start of the action of the external pressure by a predetermined time.

[0062] The pressure delay unit (323) includes a first opening (323a) formed in the pressure sensor frame (322) at a predetermined distance from the pressure sensor (322a), a second opening (323b) formed in the monitoring chamber frame (321) and connecting the first opening (323a) and the monitoring chamber (321a), and a porous membrane (323c) coupled to the first opening (323a).

[0063] Here, the second opening (323b) is formed adjacent to the first opening (323a) and spaced apart from the communication space (321b) by a predetermined distance, and the size of the second opening (323b) is formed smaller than the size of the first opening (323a) to prevent a sudden change in pressure. In this way, the monitoring chamber (321a) communicates with the outside through the first opening (323a) and the second opening (323b), and the first opening (323a) is sealed by the porous membrane (323c), so that the external pressure can also act on the pressure inside the monitoring chamber (321a). In addition, the size of the second opening (323b) is formed smaller than the size of the first opening (323a), so that a predetermined delay time occurs for the external pressure to be reflected in the pressure inside the monitoring chamber (321a), thereby preventing a sudden change in pressure.

[0064] Next, the additional configuration of the pressure monitoring unit (320) is described.

[0065] The pressure sensor frame (322) may further include a circuit element (not shown), a memory (322b), and a communication module (322c).

[0066] A circuit element (not shown) is arranged around the pressure sensor (322a), and a memory (322b) stores an identification number or calibration information of the pump assembly (300), and can be coupled to the lower surface of the pressure sensor frame (322) together with the pressure sensor (322a). At this time, the shape of the communication space (321b) can be formed in a shape corresponding to the shapes of the pressure sensor (322a) and the memory (322b). In addition, the communication module (322c) is coupled to one side of the pressure sensor frame (322) on the opposite side of the monitoring chamber frame (321), and transmits the pressure of the monitoring chamber (321a) measured by the pressure sensor (322a) and unique information about the pump assembly (300) included in the memory (322b) to the outside.

[0067] In addition, the monitoring chamber frame (321) may further include a trench (321c) for joining a sealing member that seals the joint portion with the pressure sensor frame (322). The trench (321c) is formed along the periphery opposite the monitoring chamber (321a), and a sealing member that seals the joint portion with the pressure sensor frame (322) is arranged. The joint portion of the monitoring chamber frame (321) and the pressure sensor frame (322) can be more firmly sealed by the trench (321c).

[0068] Referring again to FIG. 3, the injection assembly (400) injects the drug discharged from the pump assembly (300) through the insertion tube into the injection target. A needle or cannula may be used as the insertion tube.

[0069] The circuit unit (500) is equipped with electronic components necessary for driving and controlling the pump assembly (300), and includes a control unit that controls the operation of the drug injection device (10).

[0070] Figure 16 is a block diagram schematically showing a drug injection device according to one embodiment of the present invention.

[0071] The control unit (510) determines whether a path through which a drug moves within the pump assembly (300) or a path through which a drug moves within the injection assembly (400), such as an insertion tube, is blocked based on the internal pressure of the pump assembly (300). At this time, a pressure monitoring unit (320) is used to measure the internal pressure of the pump assembly (300).

[0072] Fig. 17 is a flowchart illustrating a method for detecting insertion tube blockage according to one embodiment of the present invention. A method for detecting a ureter blockage will be described with reference to Fig. 17.

[0073] The method (S100) for detecting a clogged flow path performed by a drug injection device (10) is such that the pump assembly (300) measures the internal pressure at predetermined intervals (step S110), the control unit (510) determines whether the flow path through which the drug moves is clogged based on the measured pressure (steps S120 and S130), and if the flow path is determined to be clogged in step S120, a notification is output (step S140).

[0074] Fig. 18 is a flowchart illustrating one embodiment of a step for determining whether a flow path is blocked, as illustrated in Fig. 17. Referring to Fig. 18, a process (step S120) for determining whether a flow path is blocked according to one embodiment will be described.

[0075] The process for determining whether the flow path is blocked (step S120) determines whether the pressure measured in step S110 exceeds a first threshold value (step S121). If the measured pressure exceeds the first threshold value in step S121, the flow path is determined to be blocked (step S122).

[0076] FIG. 19 is a flow chart for explaining another embodiment of the step for determining whether a flow path is blocked, as shown in FIG. 17. Referring to FIG. 19, a process for determining whether a flow path is blocked (step S130) according to another embodiment is explained.

[0077] The process for determining whether the flow path is blocked (step S130) determines whether the difference between the pressure measured at a first point in time and the pressure measured at a second point in time exceeds a second threshold value (step S131). If the pressure difference exceeds the second threshold value in step S131, the accumulated number of times is counted (step S132), and it is determined whether the accumulated number of times exceeds a set value (step S133). If the accumulated number of times exceeds the set value in step S133, it is determined that the flow path is blocked (step S134).

[0078] Additionally, the two embodiments of the step for determining whether a flow path is blocked described above may be combined. For example, if the pressure measured in step S121 does not exceed the first threshold value, step S131 may be performed.

[0079] Those skilled in the art will appreciate that, based on the above description, the present invention can be readily modified into other specific forms without altering the technical spirit or essential characteristics thereof. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. The scope of the present invention is defined by the following claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

[0080] The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims

1. In the pump assembly of the drug injection device, An electroosmotic pump including a monitoring chamber that is a pressure measurement target, and which generates positive and negative pressures electrochemically alternately to suck and discharge a fluid to be transported; and A pump assembly comprising a pressure monitoring unit coupled to one side of the monitoring chamber and measuring the internal pressure of the monitoring chamber.

2. In paragraph 1, The above pressure monitoring unit, A monitoring chamber frame coupled to one side of the above monitoring chamber and having a communication space formed therein; A pressure sensor frame laminated on the monitoring chamber frame on the opposite side of the monitoring chamber; and A pump assembly comprising a pressure sensor coupled to the pressure sensor frame and measuring the pressure of the monitoring chamber through the communication space of the monitoring chamber frame.

3. In paragraph 1, The above electroosmotic pump comprises a pressure generating unit that electrochemically generates positive and negative pressures alternately; and It includes a first isolation part and a second isolation part coupled to one side and the other side of the pressure generating part, A pump assembly, wherein the monitoring chamber is formed between the first isolation unit and the pressure monitoring unit.

4. In paragraph 2, The above pressure monitoring unit, A pump assembly communicating with the monitoring chamber and further including a pressure delay unit that allows external pressure to act on the internal pressure of the monitoring chamber, but delays the start of the pressure act by a predetermined time.

5. In paragraph 4, The above pressure delay unit, a first opening formed in the pressure sensor frame; and A second opening formed in the monitoring chamber frame and connecting the first opening and the monitoring chamber; and A pump assembly comprising a porous membrane coupled to the first opening.

6. In paragraph 5, A pump assembly, wherein the size of the second opening is smaller than the size of the first opening.

7. In paragraph 5, The first opening of the pressure sensor frame is formed at a predetermined distance from the pressure sensor, The second opening of the above monitoring chamber frame is formed adjacent to the first opening, A pump assembly, wherein the communication space of the monitoring chamber frame is formed spaced apart from the second opening and formed in an area corresponding to the pressure sensor.

8. In paragraph 7, The above communication space is, A pump assembly wherein the pressure sensor is exposed to the monitoring chamber, but the area or volume of the connected space is formed to be minimized.

9. In paragraph 2, The above pressure sensor frame, A pump assembly further comprising a circuit element disposed around the pressure sensor.

10. In paragraph 2, The above pressure sensor frame, A pump assembly further comprising a memory in which an identification number or calibration information of the pump assembly is stored.

11. In paragraph 2, The above pressure sensor frame, A pump assembly further comprising a communication module that transmits the pressure measured by the pressure sensor to the outside.

12. In paragraph 11, The above communication module, A pump assembly coupled to one side of the pressure sensor frame, opposite the monitoring chamber frame.

13. In paragraph 2, The above monitoring chamber frame, A pump assembly, wherein a trench is formed on the opposite side of the monitoring chamber frame along its perimeter for joining a sealing member that seals the joint portion with the pressure sensor frame.

14. A pump assembly according to any one of paragraphs 1 to 13; and A drug injection device comprising a control unit that detects blockage of the flow path of the drug injection device based on the internal pressure of the pump assembly measured in the pump assembly.

15. In a method for detecting blockage of a drug injection device, A step of measuring the internal pressure of the pump assembly at regular intervals; and A method for detecting a flow path blockage, comprising a step of determining whether a flow path of the pump assembly is blocked based on the internal pressure measured in the pump assembly.

16. In paragraph 15, The step of determining whether the above euro is blocked is as follows: a step of determining whether the measured pressure exceeds a first threshold value; and A method for detecting a blockage in a euro, comprising a step of determining that a blockage in a euro has occurred when the first threshold value is exceeded.

17. In paragraph 15, The step of determining whether the above euro is blocked is as follows: A step of determining whether the difference between the pressure measured at the first point in time and the pressure measured at the second point in time exceeds a second threshold value; and A step of counting the accumulated number of times when the difference in the above pressure exceeds the second threshold value; A step of determining whether the above accumulated number of times exceeds a set value; and A method for detecting a blockage in a euro, further comprising a step of determining that a blockage has occurred when the above-mentioned accumulated number of times exceeds the above-mentioned set value.

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