Drug injection detection unit, drug injection device comprising same, and method for operating drug injection device

Abstract

The drug injection device according to the present invention comprises: a drug storage unit the thickness of which varies according to the amount of drug to be injected; a pump assembly which is connected to the drug storage unit, and draws in and discharges the drug stored in the drug storage unit; and a drug injection detection unit which detects a change in the thickness of the drug storage unit and controls the operation of the drug injection device according to the change in the amount of the drug stored.

Description

Drug injection detection unit, drug injection device including same, and method of operating drug injection device

[0001] The present invention relates to a drug injection detection unit, a drug injection device including the same, and a method of operating 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] The insulin injector is initially operated without any drug in the drug reservoir, and operation of the insulin injector begins when drug filling in the drug reservoir is detected.

[0006] Therefore, a device capable of effectively detecting drug filling in a drug storage unit is required.

[0007] The present invention, in order to solve the above-mentioned problem, has as a technical object the provision of a drug injection device including a drug injection detection unit that detects a change in the thickness of a drug storage portion.

[0008] 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.

[0009] As a technical means for solving the above-described technical problem, a drug injection detection unit according to one embodiment of the present invention includes: a support portion spaced apart from one side of a drug storage portion by a predetermined distance; a sensor coupled to one side of the support portion and arranged to be in contact with one side of the drug storage portion, the sensor detecting drug injection based on a change in the thickness of the drug storage portion; and a switch that is turned on and operates according to the state of the sensor and outputs a control signal when turned on.

[0010] In addition, a drug injection device according to one embodiment of the present invention includes a drug storage unit whose thickness changes depending on the amount of drug to be injected; a drug injection detection unit that detects a change in the thickness of the drug storage unit and outputs a control signal to initiate operation of the drug injection device; and a control unit that initiates operation of the drug injection device based on the control signal.

[0011] In addition, a method for operating a drug injection device according to an embodiment of the present invention includes: a step of injecting a drug into a drug storage portion of the drug injection device; a step of detecting drug injection based on a change in the thickness of the drug storage portion by a drug injection detection unit arranged to be in contact with the drug storage portion; and a step of outputting a control signal to a control portion of the drug injection device when drug injection is detected, the drug injection detection unit initiating the operation of the drug injection device.

[0012] According to the problem solving means of the present invention described above, the rotation angle of the sensor arm changes according to the change in the thickness of the drug storage portion, so that the injection of the drug into the drug storage portion can be easily detected.

[0013] FIG. 1 is a front perspective view of a drug injection device according to one embodiment of the present invention.

[0014] FIG. 2 is a rear perspective view of a drug injection device according to one embodiment of the present invention.

[0015] Figure 3 is a plan view of the inside of the housing shown in Figure 1.

[0016] Figure 4 is a plan view of the drug injection device with the cover portion shown in Figure 1 removed.

[0017] Figure 5 is a plan view of a drug injection device with the contact surface shown in Figure 2 removed.

[0018] Figure 6 is a plan view of the drug storage unit illustrated in Figure 4.

[0019] Figure 7 is a perspective view of the pump assembly illustrated in Figure 4.

[0020] Fig. 8 is a cross-sectional view of the port connector illustrated in Fig. 7 in the first direction.

[0021] Fig. 9 is a cross-sectional view of the port connector illustrated in Fig. 7 in the second direction.

[0022] Figure 10 is a block diagram schematically showing the configuration of the electroosmotic pump illustrated in Figure 7.

[0023] Fig. 11 is a conceptual diagram schematically showing the configuration of the driving unit illustrated in Fig. 10.

[0024] Fig. 12 is an example diagram schematically showing the operation of the driving unit illustrated in Fig. 11.

[0025] Figure 13 is a perspective view showing the combined structure of the drug injection detection unit and the drug storage unit illustrated in Figure 5.

[0026] Figure 14 is a perspective view of the drug injection detection unit illustrated in Figure 13.

[0027] Figures 15 and 16 are operation examples of the sensor shown in Figure 14.

[0028] Figure 17 is a flow chart for explaining the operation method of the drug injection device.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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."

[0033] 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, FIG. 3 is a plan view of the inside of the housing shown in FIG. 1, FIG. 4 is a plan view of the drug injection device with the cover part shown in FIG. 1 removed, and FIG. 5 is a plan view of the drug injection device with the contact surface shown in FIG. 2 removed.

[0034] Referring to FIGS. 1 to 5, a drug injection device (100) according to one embodiment of the present invention will be described. The drug injection device (100) includes a housing (110), a drug storage unit (120) disposed inside the housing (110), a pump assembly (130), a drug injection detection unit (140), an injection assembly (150), and a control unit (160).

[0035] Referring to FIGS. 1 to 5, the housing (110) may include a cover portion (111) and a contact surface (112), and a mounting space is formed between the cover portion (111) and the contact surface (112).

[0036] The cover portion (111) is formed with rounded corners so that the patch-type drug injection device (100) can remain attached. The contact surface (112) is configured to be attached to the user's body, and an outlet (112a) for withdrawing the insertion tube to the outside is formed. Here, a silicone cap can be combined with the outlet (112a), and the insertion tube inserted into the user can be fixed by the silicone cap.

[0037] The mounting space is divided into a central region (113) and first to third regions (114, 115, 116), and the first to third regions (114, 115, 116) are formed in a shape that surrounds the central region (113). In particular, the mounting space within the housing (110) is divided into first to third regions (114, 115, 116) that extend in a direction perpendicular to the insertion direction of the insertion tube, and the central region (113). Then, major components are combined in each region. In a typical case, the PCB control unit is first arranged over the entire or most of the plane of the device, and then the drug storage unit 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 order to make the patch-type drug injection device (100) of the present invention thin, the area where each component overlaps with each other is minimized.

[0038] Referring to FIGS. 4 and 5, the drug storage unit (120), the pump assembly (130), the drug injection detection unit (140), the injection assembly (150), and the control unit (160) may be arranged in the central region (113) and the first to third regions (114, 115, 116). The drug storage unit (120) and the drug injection detection unit (140) may be arranged in the first region (114), the pump assembly (130) may be arranged in the second region (115), the control unit (160) may be arranged in the third region (116), and the injection assembly (150) may be arranged in the central region (113). Accordingly, the drug storage unit (120), the pump assembly (130), the drug injection detection unit (140), and the control unit (160) may be arranged in a form that surrounds the injection assembly (150). Here, in the first region (114), a drug storage unit (120) and a drug injection detection unit (140) can be placed side by side.

[0039] In this way, the injection assembly (150) including the insertion tube is placed in the central region (113), so that the insertion tube does not fall out even when the user moves or an external impact occurs and can be maintained in a state of being injected into the user.

[0040] Next, the drug storage unit (120), pump assembly (130), drug injection detection unit (140), injection assembly (150), and control unit (160) will be described in detail.

[0041] FIG. 6 is a plan view of the drug storage unit illustrated in FIG. 4. Referring to FIG. 6, the drug storage unit (120) is described. The drug storage unit (120) stores a drug to be injected, and its thickness changes depending on the amount of the drug to be injected. The drug storage unit (120) may be provided as a flat pouch bag made of a polymer material. A flange unit (121) may be formed around the drug storage unit (120) in which both sides constituting the drug storage unit (120) are joined to a predetermined width. The flange unit (121) may limit the drug storage unit (120) from expanding around the drug.

[0042] The drug storage unit (120) is made of a release paper, and the inside and outside of the drug storage unit (120) 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 (120) is made by applying heat to a predetermined temperature at which the inside material melts to form a flange portion (121). 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 (121) is formed.

[0043] In addition, the drug storage unit (120) is coupled with a drug inlet / outlet (122) through which drugs are introduced, so that drugs are introduced into the drug storage unit (120) or drugs stored in the drug storage unit (120) are discharged to the outside.

[0044] FIG. 7 is a perspective view of the pump assembly illustrated in FIG. 4, FIG. 8 is a cross-sectional view of the port connector illustrated in FIG. 7 in a first direction, and FIG. 9 is a cross-sectional view of the port connector illustrated in FIG. 7 in a second direction.

[0045] Next, the pump assembly (130) will be described with reference to FIGS. 7 to 9. The pump assembly (130) is connected to the drug storage unit (120), draws in a drug from the drug storage unit (120), and discharges the drug into the insertion tube of the injection assembly (150). The pump assembly (130) may include an electroosmotic pump (131) and a port connector (132). The electroosmotic pump (131) is an electrochemically driven pump, which will be described in detail later.

[0046] Referring to Fig. 8, the port connector (132) is formed with an inflow path (132a) through which a drug is introduced from the drug storage unit (120) to the electroosmotic pump (131) and a discharge path (132b) through which a drug is discharged from the electroosmotic pump (131) to the injection assembly (150). In addition, referring to Fig. 9, the port connector (132) may further include a drug injection path (132c). The drug injection path (132c) is formed in a direction intersecting the direction in which the first path (132a) advances, has one end communicated with the first path (132a), and has the other end open to the outside. The drug injection path (132c) is a path through which a drug can be injected into the first path (132a) using a drug injection syringe, and is used when filling the drug into the drug storage unit (120) at the initial stage of operation of the drug injection device (100) of the present invention.

[0047] Next, the electroosmotic pump (131) will be described in detail with reference to FIGS. 10 to 12.

[0048] Figure 10 is a block diagram schematically showing the configuration of the electroosmotic pump (131) illustrated in Figure 7.

[0049] Referring to Fig. 10, the electroosmotic pump (131) will be described in detail. The electroosmotic pump (131) includes a driving unit (133) and a chamber (134). The driving unit (133) is electrochemically driven by a control signal to generate positive pressure and negative pressure, and discharges a drug according to the positive pressure and negative pressure. The chamber (134) draws a drug from the drug storage unit (120) according to the pressure of the driving unit (133) and then discharges the drug to the injection assembly (150). 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.

[0050] Fig. 11 is a conceptual diagram schematically showing the configuration of the driving unit illustrated in Fig. 10, and Fig. 12 is an exemplary diagram schematically showing the configuration of the driving unit illustrated in Fig. 11.

[0051] Referring to FIGS. 11 and 12, the driving unit (133) is described in detail. The driving unit (133) 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 the pumping unit (membrane, 133a). The driving unit (133) may include a power source (133d) that applies voltage or current to the membrane (133a) and the first electrode (133b) and the second electrode (133c) arranged on both sides of the membrane (133a), a first diaphragm (133e) for moving the fluid, and a second diaphragm (133f). Each diaphragm (133e, 133f) is provided on one side and the other side of the pumping unit (133a), and its shape is changed by the movement of the pumping solution as positive pressure and negative pressure are alternately generated. For example, the first diaphragm (133e) and the second diaphragm (133f) transfer the negative pressure and positive pressure generated by the operation of the pumping unit (133a) to the fluid to be transported. More specifically, when negative pressure is generated, at least a part of the first diaphragm (133e) and the second diaphragm (133f) moves backward (when moving in the ① direction), and the fluid to be transported is sucked into the chamber (134). Conversely, when positive pressure is generated, at least a part of the first diaphragm (133e) and the second diaphragm (133f) moves forward (when moving in the ② direction), and the fluid to be transported is discharged from the chamber (134).

[0052] The materials used for the membrane (133a) are generally silica, glass, etc., and when these are immersed in an aqueous solution, their surfaces become negatively charged. The membrane (133a) 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 (133b) and a (-) voltage is applied to the second electrode (133c), a negative pressure is generated, and the fluid inside the driving unit (133) moves in direction ① due to this negative pressure. At this time, the drug is inhaled through the inhalation path (136) and flows into the chamber (134) through the inhalation valve (135). At this time, the discharge valve (137) is closed so that negative pressure is not transmitted to the discharge path (138). Conversely, when a (-) voltage is applied to the first electrode (133b) and a (+) voltage is applied to the second electrode (133c), a positive pressure in the opposite direction is generated by a reversible electrochemical reaction. The fluid inside the driving unit (133) moves in the ② direction due to this positive pressure. At this time, the drug stored in the chamber (134) is injected into the subject through the discharge valve (137) and the discharge path (138). At this time, the suction valve (135) is closed so that positive pressure is not transmitted to the suction path (136).

[0053] This phenomenon is called electroosmosis, and a pump utilizing this principle is an electroosmotic pump (131). In the present invention, since an electroosmotic pump (131) is used as a driving means in a patch-type drug injection device (100), the driving means can be manufactured thinner than in other technologies using electric motors, etc. Accordingly, the overall thickness of the patch-type drug injection device (100) can be manufactured thinner, allowing for more stable bonding to the skin.

[0054] Referring again to FIG. 5, the drug injection detection unit (140) detects a change in the thickness of the drug storage unit (120) and controls the operation of the drug injection device (100) according to the change in the drug storage amount.

[0055] Next, the detailed configuration of the drug injection detection unit (140) is described. Fig. 13 is a perspective view showing the combined structure of the drug injection detection unit and the drug storage unit shown in Fig. 5, Fig. 14 is a perspective view of the drug injection detection unit shown in Fig. 13, and Figs. 15 and 16 are operation example diagrams of the sensor shown in Fig. 14.

[0056] Referring to FIG. 13, the drug injection detection unit (140) is arranged on one side of the drug storage unit (120), detects a change in the thickness of the drug storage unit (120) into which the drug is injected, and controls the operation of the drug injection device (100) according to a change in the amount of drug stored in the drug storage unit (120). When the drug injection device (100) is used for the first time, the drug injection detection unit (140) detects when a drug is injected into the drug storage unit (120) and operates the drug injection device (100).

[0057] Specifically, referring to FIG. 14, the drug injection detection unit (140) may include a support (141), a sensor (142), and a switch (not shown). The support (141) is placed in the mounting space of the drug injection device (100) at a predetermined distance from one side of the drug storage unit (120), and the support (141) may be implemented as a PCB.

[0058] Referring to FIGS. 15 and 16, the sensor (142) is coupled to one side of the support (141) and is arranged to be in contact with one side of the drug storage unit (120), thereby detecting the injection of a drug into the drug storage unit (120) based on a change in the thickness of the drug storage unit (120). The sensor (142) may include a main body (142a) coupled to the support (141) and a sensor arm (142b) that rotates along a pivot axis. The sensor arm (142b) may be arranged so that an end thereof is in contact with one side of the drug storage unit (120). Specifically, the operation of the sensor (142) will be described. When a drug is injected into the drug storage unit (120) and the thickness of the drug storage unit (120) increases, the drug storage unit (120) presses the sensor arm (142b), thereby detecting the injection of the drug.

[0059] The sensor arm (142a) may initially be rotated to form a predetermined angle with the main body (142a) of the sensor (142), as shown in FIG. 15. In this state, the end of the sensor arm (142b) comes into contact with one surface of the drug storage unit (120). Thereafter, when a drug is injected into the drug storage unit (120), the drug storage unit (120) expands, and as the drug storage unit (120) expands, it pressurizes the sensor arm (142b). Accordingly, as the volume of the drug storage unit (120) increases, the sensor arm (142b) is pressurized, and as shown in FIG. 16, the rotation angle of the sensor arm (142a) changes, and a switch (not shown) is activated. As a result, a control signal for initiating the operation of the drug injection device (100) may be output to the control unit of the drug injection device.

[0060] Accordingly, it is possible to detect that drug filling has begun by pressing and rotating the sensor arm (142b) due to an increase in the thickness of the drug storage unit (120). However, the sensor (142) is not limited to a configuration including the sensor arm (142b), and any sensor capable of detecting a change in the thickness of the drug storage unit (120) can be applied.

[0061] A switch (not shown) is turned on according to the state of the sensor (142) and outputs a control signal for controlling the operation of the drug injection device (100) when turned on. The switch (not shown) may be built into the main body (142a) of the sensor (142) and is turned on according to the rotation angle of the sensor arm (142b) to output a control signal for controlling the operation of the drug injection device (100) to the control unit. Specifically, when the rotation angle of the sensor arm (142b) is less than a preset angle, the switch (not shown) is turned on and outputs a control signal for initiating the operation of the drug injection device (100) to the control unit (160). That is, assuming that Fig. 15 is the initial state, and the extension direction of the sensor arm (142b) and the main body (142a) or support (141) of the sensor (142) has a first angle, when the sensor arm (142b) is rotated to reach a second angle smaller than the first angle, or when it has an angle of 0 degrees, as in Fig. 16, the switch (not shown) is turned on.

[0062] Additionally, the drug delivery detection sensor (140) may further include a communication unit (143) that transmits a control signal to the control unit of the drug injection device (100).

[0063] Referring again to FIG. 4, the injection assembly (150) injects the drug discharged from the pump assembly (130) including the insertion tube into the injection target, and the control unit (160) has electronic components required for driving and controlling the pump assembly (130) mounted thereon, and has a built-in control unit that operates the drug injection device (100) through a control signal transmitted from the drug main detection unit (140).

[0064] Next, the additional configuration of the patch-type drug injection device (100) will be described with reference to FIGS. 1 and 2.

[0065] Referring to FIG. 1, a cover portion (111) of a housing (110) may have a shooting hole (111a) formed in an area corresponding to an area where an injection assembly (150) is positioned. The shooting hole (111a) is a hole (111a) that transmits an external force to the injection assembly (150) by an applicator (not shown) so that an insertion tube can be inserted into the user. A silicone cap may be coupled to the shooting hole (111a).

[0066] Referring to Fig. 2, a drug injection hole (112b) and an air vent hole (112c) may be formed on the contact surface (112) of the housing (110). The drug injection hole (112b) is a hole for supplying a drug to be stored in the drug storage unit (120) from the outside, and the air vent hole (112c) is a hole for removing a pressure difference between the inside and outside of the housing (110).

[0067] In addition, the patch-type drug injection device (100) may include a sound output device (not shown) inside the housing (110) to provide a notification for a specific situation. In addition, the control unit (160) may include a switch that can stop the operation of the sound output device (not shown), and a buzzer stop hole (112d) that provides a passage for operating the switch of the control unit (160) may be formed in the contact surface (112). Here, a silicone cap may be combined with the drug injection hole (112b), and an air vent sticker may be attached to the air vent hole (112c) and the buzzer stop hole (112d).

[0068] Figure 17 is a flow chart for explaining the operation method of the drug injection device.

[0069] Referring to FIGS. 2, 13, 14, and 17, the operating method (S100) of the drug injection device will be described. In the initial operating method (S100) of the drug injection device, when a drug is injected into the drug storage unit (120) through the drug injection hole (112b) by a user (step S110), the drug injection detection unit (140) detects the drug injection based on the thickness change of the drug storage unit (120) (step S120). When the drug injection is detected in step S120, the drug injection detection unit (140) outputs a control signal to the control unit of the drug injection device (100) to initiate the operation of the drug injection device (100). Then, the drug injection device (100) is operated.

[0070] In step S120, drug injection detection is performed when the sensor arm (142b) is pressurized by a change in the thickness of the drug storage unit (120), and the rotation angle of the sensor arm (142b) becomes less than a preset angle, and the sensor (142) detects drug injection. When drug injection is detected, the switch of the sensor (142) outputs a control signal to the control unit (160) of the drug injection device (100) in step S130.

[0071] 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.

[0072] 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 a drug injection detection unit that detects that a drug is injected into a drug storage unit, A support portion spaced apart from one side of the above drug storage portion by a predetermined distance; A sensor coupled to one side of the support and positioned to be in contact with one side of the drug storage unit, the sensor detecting drug injection based on a change in the thickness of the drug storage unit; and A switch that is turned on and operates according to the status of the above sensor and outputs a control signal when turned on, The above sensor, a main body coupled to the above support; and A sensor arm is coupled to the pivot of the above body and is rotatable along the pivot axis, The above sensor arm, A drug injection detection unit, wherein the end portion is positioned so as to be in contact with one side of the drug storage unit.

2. In paragraph 1, The above switch is, Initially it is turned off, A drug injection detection unit that outputs a control signal to the control unit of the drug injection device to initiate operation of the drug injection device when the sensor arm is turned on by the sensor when the angle at which the sensor arm is rotated becomes less than a preset angle.

3. In paragraph 2, The above switch is, Built into the body of the above sensor, A drug injection detection unit that is turned on by rotation of the above sensor arm.

4. In the drug injection device, A drug reservoir whose thickness varies depending on the amount of drug injected; A drug injection detection unit that detects a change in the thickness of the drug storage unit and outputs a control signal to initiate operation of the drug injection device; A control unit that initiates the operation of the drug injection device based on the control signal; and A pump assembly connected to the drug storage unit and configured to suck and discharge the drug stored in the drug storage unit, The drug is injected into the drug storage unit through a drug injection path formed on one side of the pump assembly. The above drug injection detection unit, A support portion spaced apart from one side of the above drug storage portion by a predetermined distance; A sensor coupled to one side of the support and positioned to be in contact with one side of the drug storage unit, the sensor detecting drug injection based on a change in the thickness of the drug storage unit; and A drug injection device comprising a switch that is turned on according to the status of the above sensor and outputs a control signal when turned on.

5. In paragraph 4, The above sensor, a main body coupled to the above support; and A sensor arm coupled to the pivot of the above body and rotatable along the pivot axis, The above sensor arm, A drug injection device, wherein the end is positioned so as to be in contact with one side of the drug storage unit.

6. In paragraph 4, The above switch is, Initially it is turned off, A drug injection device, wherein when the rotation angle of the sensor arm becomes less than a preset angle and is turned on by the sensor, a control signal for initiating operation of the drug injection device is output to the control unit.

7. In paragraph 6, The above switch is, Built into the body of the above sensor, A drug injection device that is turned on by rotation of the above sensor arm.

8. In paragraph 4, The above drug storage unit, A drug injection device having a pouch structure in which two sides are joined together, the thickness of which increases as a drug is filled, and one side presses the other side of the sensor arm.

9. In the method of operating the drug injection device, A step of injecting a drug into the drug storage compartment of the above drug injection device; A step of detecting drug injection based on a change in the thickness of the drug storage unit by a drug injection detection unit arranged to be in contact with the drug storage unit; and When drug injection is detected, the drug injection detection unit includes a step of outputting a control signal to the control unit of the drug injection device to initiate operation of the drug injection device, The step of detecting the above drug injection is: An operating method of a drug injection device, wherein the sensor arm is pressurized by a change in the thickness of the drug storage portion, and drug injection is detected when the rotation angle of the sensor arm becomes less than a preset angle.

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