Drug delivery device

Abstract

[Problem] To provide a medicine dispensing device that more accurately detects the dispensing status of medicine. [Solution] The medicine dispensing device (100) includes: a pusher (130) that pushes out medicine from a medicine container (110) filled with medicine; a drive mechanism (140) that causes the pusher to move forward and backward relative to the front opening of the medicine container; and a control unit (150) that controls the operation of the drive mechanism. In this medicine dispensing device, the drive mechanism has a motor (141) that generates a driving force for moving the pusher forward and backward, and a rotation detection unit (144) that detects the rotation of the motor. The control unit has an operation confirmation function that confirms the operation status of the motor based on the detection result of the rotation detection unit. After confirming that the motor has stopped through the operation confirmation function, the control unit reverses the motor and starts it up, and determines whether the pusher has moved backward.

Description

Technical Field

[0001] This invention relates to a drug delivery device. Background Technology

[0002] Previously, an injection pump-type drug delivery device was known, which delivers a drug solution filled in a drug solution container into a living organism through the pushing action of a pushing member. The drug delivery device has a drive mechanism with a motor that generates driving force and a control unit that controls the drive mechanism.

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-181869 Summary of the Invention

[0006] The medication delivery device delivers medication to the organism by advancing a pusher bit by bit via a drive mechanism. Therefore, when the pusher stops, the medication delivery also stops. However, if the medication delivery device determines that the delivery is complete when the motor stops (the pusher stops), then even if the motor stops due to an abnormality occurring within the device (such as a motor malfunction), it is possible to determine that the delivery is complete.

[0007] Therefore, the object of the present invention is to provide a drug delivery device that can more accurately detect the drug delivery status.

[0008] The medicine dispensing device of the present invention includes: a pushing member that pushes out the medicine from a medicine container filled with medicine; a driving mechanism that causes the pushing member to move forward and backward relative to the front opening of the medicine container; and a control unit that controls the operation of the driving mechanism. In this medicine dispensing device, the driving mechanism has a motor that generates a driving force for moving the pushing member forward and backward, and a rotation detection unit that detects the rotation of the motor. The control unit has an operation confirmation function that confirms the operation status of the motor based on the detection result of the rotation detection unit. After the control unit confirms that the motor has stopped through the operation confirmation function, it reverses and starts the motor and determines whether the pushing member has moved backward.

[0009] Invention Effects

[0010] According to the medicine dispensing device of the present invention, after confirming that the motor has stopped, the control unit reverses and starts the motor, and determines whether the pusher has retracted. Thus, the control unit can confirm the motor's operating status and determine whether an abnormality in medicine dispensing has occurred due to a motor malfunction. Therefore, the medicine dispensing device can more accurately detect the medicine dispensing status. Attached Figure Description

[0011] Figure 1 This is a side view of the drug delivery system of this embodiment.

[0012] Figure 2 This is a diagram illustrating an example of the use of the drug delivery system of this embodiment.

[0013] Figure 3 This is a perspective view of the drug delivery device constituting the drug delivery system of this embodiment.

[0014] Figure 4 This is an exploded perspective view of the drug delivery device of this embodiment.

[0015] Figure 5 This is a partial cross-sectional view of the front end of the drug delivery device in this embodiment.

[0016] Figure 6 This is a block diagram of the control system of the drug delivery device in this embodiment.

[0017] Figure 7 This is a schematic diagram illustrating a rotating detection unit, etc.

[0018] Figure 8A This is a cross-sectional view of a liquid dispensing device, showing the stopped state of the pusher when dispensing is complete and the state in which the pusher has retracted.

[0019] Figure 8B This is a cross-sectional view of a liquid dispensing device showing the stopped state of the pusher and the state in which the pusher is retracted when an abnormality occurs (when the supply path is blocked).

[0020] Figure 9 This is a flowchart of the operation of the control unit in this embodiment.

[0021] Figure 10 This is a flowchart of the operation of the control unit in the second embodiment. Detailed Implementation

[0022] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, the following description does not limit the technical scope and meaning of the terms used in the claims. Additionally, the dimensions in the drawings have been exaggerated for ease of explanation and may differ from actual dimensions.

[0023] Figures 1 to 8B This is a diagram illustrating the drug delivery system 10, drug delivery device 100, and delivery apparatus 200 of the embodiment. Arrow X added to each diagram indicates the "length direction (length direction of the drug container 110)" of the drug delivery device 100, arrow Y indicates the "width direction (depth direction)" of the drug delivery device 100, and arrow Z indicates the "height direction" of the drug delivery device 100.

[0024] (Drug delivery system)

[0025] The drug delivery system 10 is used to deliver a drug solution into a living organism. For example... Figure 1 As shown, the drug delivery system 10 includes a drug delivery device 100 and a delivery instrument 200.

[0026] like Figure 2 As shown, the medication delivery device 100 and delivery instrument 200 are configured as patches for use on the user's body surface (skin). The body part of the user on which the medication delivery device 100 and delivery instrument 200 are installed is not particularly limited, for example, the abdomen or thigh.

[0027] The drug delivery system 10 can, for example, continuously deliver a drug solution (not shown) filled in the drug container 110 of the drug delivery device 100 into the organism over a relatively long period of time (e.g., a few minutes to a few hours) by the pushing action of the pushing member 130 described later. In addition, the drug delivery system 10 can also deliver the drug solution into the organism intermittently.

[0028] (Drug administration device)

[0029] like Figure 3 and Figure 4 As shown, the medicine dispensing device 100 includes: a medicine container 110 for filling with medicine; a housing 120 for holding the medicine container 110; a pusher 130 for pushing the medicine out of the medicine container 110; a drive mechanism 140 for moving the pusher 130 forward and backward relative to the front opening of the medicine container 110; a control unit 150 for controlling the operation of the drive mechanism 140; and a power supply unit 160.

[0030] like Figure 3 and Figure 4 As shown, the outer casing 120 has: a box-shaped outer casing main body 121 with an internal receiving space; a chassis 122 that is received within the receiving space of the outer casing main body 121 and can be fixed relative to the outer casing main body 121; and a cover member 123 that is mounted on the outer casing main body 121 with the chassis 122 received within the receiving space.

[0031] like Figures 3-5 As shown, a gasket C is embedded in the opening of the main body 121 of the outer casing. Figure 5 As shown, the gasket C makes linear contact with the liquid container 110 in the circumferential direction. Furthermore, Figure 5 For ease of explanation, only a cross-section of the main body 121 and the liner C is shown.

[0032] like Figure 3 and Figure 4As shown, a window 124 is formed on the upper surface 121a of the outer casing 121, allowing the interior of the receiving space to be visually identified from the outside of the outer casing 120. The window 124 is formed by partially providing a transparent or semi-transparent portion in the outer casing 121.

[0033] like Figure 4 As shown, a base opening 125 for inserting the base frame 122 into the receiving space of the housing body 121 is formed on the base end side in the longitudinal direction of the housing body 121. Figure 3 and Figure 4 As shown, the base opening 125 of the outer shell body 121 is closed by the cover member 123 when the base frame 122 is housed in the receiving space.

[0034] like Figure 4 As shown, a sheet-like attachment portion (not shown) is provided on the bottom surface 121b of the main body 121 of the outer casing, which can be attached to the user's body surface H. In the initial state before the medicine dispensing device 100 is installed on the user, a peelable protective sheet is installed on the attachment surface of the attachment portion.

[0035] The base frame 122 holds the liquid container 110, the pusher 130, the drive mechanism 140, the control unit 150, and the power supply unit 160.

[0036] The drug container 110 is a so-called pre-filled drug container. Therefore, the drug solution is pre-filled into the inner cavity 111 of the drug container 110. Examples of drugs that can be included include protein preparations, anesthetic analgesics, and diuretics.

[0037] A sealing component (not shown) is provided at the front opening (outlet) of the front end 112 of the liquid medicine container 110 to prevent leakage of the liquid medicine. Figure 3 As shown, the front end 112 of the liquid medicine container 110 is arranged to protrude outward from the outer shell body 121. Furthermore, a tube 240 (described later) is installed at the front end of the liquid medicine container 110 protruding from the outer shell body 121. Figure 1 The mounting part 115 is used for connection.

[0038] like Figure 4 As shown, a pusher 130 is inserted into the inner cavity 111 of the medicine container 110. The front end of the pusher 130 is provided with a feature that allows it to slide along the inner wall 110a of the medicine container 110 (see reference). Figure 8A , Figure 8BThe sliding washer 131. Regarding washer 131, its base end is sealed in a liquid-tight manner by the outer periphery of washer 131 being tightly pressed against the inner periphery of the liquid container 110. Washer 131 can advance by advancing the pusher 130 along the length direction X and pushing it with its front end; however, there is no mechanical connection between the pusher 130 and washer 131. When the pusher 130 is retracted to the opposite side, it separates from washer 131.

[0039] When the pusher 130 advances while the washer 131 is stopped inside the liquid container 110, the washer 131 is compressed in the direction of advance (length direction X) of the pusher 130. When the washer 131 is compressed, its thickness in the length direction X decreases compared to when it is not compressed. The state in which the washer 131 is stopped inside the liquid container 110 refers, for example, to the state in which the liquid is dispensed and the washer 131 has touched the inner wall 110b of the front end side of the liquid container 110 (see reference). Figure 8A (See the diagram above) The medicine supply path (such as the dispensing device 200) in the medicine dispensing system 10 is blocked and the gasket 131 comes into contact with the medicine remaining in the medicine container 110 (refer to the diagram above). Figure 8B (See the image above). Washer 131 can be made of, for example, a soft resin material such as rubber or an elastomer.

[0040] The drive mechanism 140 includes: a motor 141 that receives drive current from a power supply unit 160 and generates a driving force for moving the push member 130 forward and backward; a reduction mechanism 142 that includes gears for transmitting the rotational driving force of the motor 141; a feed screw 143 connected to the reduction mechanism 142; and a rotation detection unit 144 for detecting the rotation of the motor 141.

[0041] The feed screw 143 converts the rotary motion transmitted from the reduction mechanism 142 into linear motion, causing the pusher 130 to move forward and backward along the length direction X.

[0042] The feed screw 143 is screwed near the base of the pusher 130. The feed screw 143 converts the rotational motion transmitted from the reduction mechanism 142 into linear motion, causing the pusher 130 to advance and retract along the length direction X. The pusher 130 advances the washer 131 by advancing towards the front end of the liquid container 110, so as to push the liquid from the inner cavity 111 of the liquid container 110 into the tube 240 (see reference). Figure 1 )roll out.

[0043] The rotation detection unit 144 is an encoder located at the front end of the motor 141. For example... Figure 6 , Figure 7As shown, the encoder comprises an optical interruptor 144a equipped with an optical sensor and a slit plate 144b with multiple slits radially formed. The slit plate 144b rotates as the motor 141 rotates. The rotation detection unit 144 uses the optical sensor of the optical interruptor 144a to detect whether light passes through the slits of the slit plate 144b, thereby detecting the rotation of the motor 141. Furthermore, this embodiment illustrates an encoder using an optical interruptor 144a as the rotation detection unit 144, but an encoder using a magnetic sensor could also be used. Additionally, the position of the rotation detection unit 144 is not limited to... Figure 6 , Figure 7 As illustrated in the diagram, the rotation detection unit 144 can also be placed between the motor 141 and the reduction mechanism 142 to directly detect the rotation of the motor 141.

[0044] The control unit 150 controls the drug delivery operation of the drug delivery device 100. The control unit 150 can be, for example, a well-known microcomputer (electronic circuit element) equipped with a CPU, RAM, ROM, etc. The control unit 150 uniformly controls the operation of the drive mechanism 140 and the power supply unit 160.

[0045] The power supply unit 160 can be made of, for example, a well-known button battery.

[0046] The control unit 150 is electrically connected to the power supply unit 160, the motor 141, and the rotation detection unit 144. The motor 141 rotates by power supplied from the power supply unit 160, and the rotational speed of the motor 141 is controlled by the control unit 150 based on the detection results of the rotation detection unit 144.

[0047] The medication delivery device 100 delivers medication to the organism by advancing the pusher 130 (washer 131) within the medication container 110 via the control unit 150. At this time, the control unit 150 causes the motor 141 to rotate forward. Conversely, when the washer 131 stops in the opposite direction to the advancing pusher 130, medication is no longer dispensed from the medication container 110, and medication delivery ceases. The control unit 150 can confirm, based on the detection results from the rotation detection unit 144, that the motor 141 has stopped along with the stop of the washer 131.

[0048] In the drug delivery device 100, the control unit 150 performs its functions after confirming that the motor 141 has stopped. Figure 9 , Figure 10 The confirmation action shown allows for more accurate detection of the drug delivery status. Details regarding the confirmation action of the control unit 150 will be described later.

[0049] Next, the functions of the control unit 150 will be explained.

[0050] The control unit 150 has an operation confirmation function that confirms the operating status of the motor 141 based on the detection results of the rotation detection unit 144. When the control unit 150 starts the motor 141 (forward or reverse rotation), if the rotation detection unit 144 detects the rotation of the motor 141 (whether light passes through), it can be determined that the motor 141 is operating. On the other hand, when the control unit 150 starts the motor 141 (forward or reverse rotation), if the rotation detection unit 144 does not detect the rotation of the motor 141, it can be determined that the motor 141 is in a stopped state. Furthermore, in this embodiment, an encoder using an optical interruptor 144a is exemplified as the rotation detection unit 144, but an encoder using a magnetic sensor may also be used.

[0051] In addition, the control unit 150 can detect the number of rotations of the motor 141 through the action confirmation function.

[0052] The control unit 150 has a speed calculation function that calculates the speed of the motor 141 based on the detection results of the rotation detection unit 144. When the administration of the medicine begins, the control unit 150 can calculate the speed of the motor 141 based on the interval of rotation of the motor 141 (with or without light passing) detected by the rotation detection unit 144. The speed of the motor 141 has the characteristic that, while keeping the current flowing to the motor 141 constant, it decreases as the load increases (torque increases) and increases as the load decreases. In addition, the control unit 150 has a current measurement function that measures the current flowing to the motor 141. The current value flowing to the motor 141 has the characteristic that, while keeping the speed of the motor 141 constant, it increases as the load increases (torque increases) and decreases as the load decreases.

[0053] The control unit 150 uses a rotation speed calculation function to increase the current flowing to the motor 141 when the rotation speed of the motor 141 decreases and decreases the current flowing to the motor 141 when the rotation speed of the motor 141 increases. This allows the control unit to maintain the rotation speed of the motor 141 at a preset speed (medication dispensing speed) during the medication dispensing period. On the other hand, if medication dispensing is completed or an abnormality occurs, even increasing the current flowing to the motor 141 will not maintain the rotation speed at the medication dispensing speed. Eventually, the current flowing to the motor 141 will reach its maximum value, and the rotation speed of the motor 141 will decrease. Therefore, if the control unit 150 determines that the washer 131 has stopped inside the medication container 110 when the rotation speed calculation function shows that the rotation speed of the motor 141 is lower than the medication dispensing speed, or when the current value measurement function shows that the current value of the motor 141 has reached its maximum value, the control unit 150 can determine that the washer 131 has stopped inside the medication container 110. In addition, in order to determine as early as possible that the washer 131 has stopped in the liquid container 110, the washer 131 can be determined to have stopped in the liquid container 110 when the rotation speed of the motor 141 reaches a set value that is less than a specified amount of the liquid delivery speed, or when the current value of the motor 141 reaches a set value that is less than a specified value of the maximum value.

[0054] (Giving tools)

[0055] like Figure 1 and Figure 2 As shown, the dispensing device 200 is configured to be connected to the liquid dispensing device 100.

[0056] The delivery device 200 includes: a connector 210; a needle 220 capable of puncturing a living organism; a puncture part (cannula housing) 230; a tube 240; and a puncture aid 250 for assisting the needle 220 in puncturing the living organism.

[0057] The connector 210 is configured to connect to the liquid dispensing device 100 via a mounting portion 215 fixed to the connector 210. The mounting portion 215 is provided relative to the front end portion 112 of the liquid container 110 protruding outside the housing 120 (see reference 115). Figure 4 It is embedded externally and can be connected to the liquid dispensing device 100.

[0058] Inside the mounting section 215 is a connecting needle (not shown) capable of piercing the sealing member (not shown) disposed at the front end 112 of the liquid container 110. The tube 240 communicates with the inner cavity 111 of the liquid container 110 via the connecting needle.

[0059] Inside the puncture section 230, a flow path (not shown) is formed that connects the inner cavities of the tube 240 and the needle tube 220. The drug solution delivered to the puncture section 230 via the tube 240 passes through the flow path formed inside the puncture section 230 and the needle tube 220 and is administered into the body.

[0060] When administering medication to a user, a puncture aid 250 is installed on the puncture site 230. The puncture aid 250 holds an insertion needle (inner needle) 251. With the puncture aid 250 installed on the puncture site 230, the insertion needle 251 is inserted into the lumen of the needle tube 220, with its tip protruding from the front end of the needle tube 220. By inserting the insertion needle 251 into the needle tube 220, the user can insert the needle tube 220 into the body without causing it to bend or kink.

[0061] After the needle 220 is inserted into the organism, the puncture aid 250 is removed from the puncture site 230. When the puncture aid 250 is removed from the puncture site 230, the guide needle 251 is pulled out from the lumen of the needle 220.

[0062] After the needle 220 is inserted into the body, the puncture aid 250 is removed and the needle 220 remains inside the body, with the puncture portion 230 remaining on the user's skin H. In this state, by advancing the pusher 130 of the drug delivery device 100 within the drug container 110, the drug solution filled in the drug container 110 is delivered to the inner lumen of the needle 220 via the flow path of the tube 240 and the puncture portion 230.

[0063] The insertion needle 251 can be made of metal, for example. Additionally, the needle tube 220 can be made of a tubular component (cannula) made of resin, for example.

[0064] The dispensing device 200, like the medication dispensing device 100, is configured as a patch for application to the user's skin surface H. A sheet-like attachment portion (not shown) is provided on the contact surface (bottom surface) 231 of the puncture portion 230 of the dispensing device 200, allowing it to adhere to the skin surface H. In the initial state before the dispensing device 200 is installed on the user, a peelable protective sheet is attached to the attachment surface of the attachment portion.

[0065] <First Implementation>

[0066] Reference Figure 9 The confirmation operation of the control unit 150 in this embodiment will be explained. Figure 9 This is a flowchart of the operation of the control unit 150 in this embodiment.

[0067] As described above, the confirmation action of the control unit 150 is performed after the drug delivery has started and the control unit 150 has confirmed through the action confirmation function that the motor 141 has stopped (the drug delivery has stopped). At this time, the control unit 150 may also stop the start of the motor 141 after confirming that the motor 141 has stopped.

[0068] First, the control unit 150 sets the first rotation number and the second rotation number of the motor 141 corresponding to the push-back amount L1 and L2 of the washer 131.

[0069] (Pushback amount L1)

[0070] If the medication has been administered, such as Figure 8A As shown in the figure above, the washer 131 stops in contact with the inner wall 110b of the front end side of the liquid container 110. When the washer 131 is released from the pressure of the pusher 130 due to the retraction of the pusher 130, its thickness increases from the compressed state that was reduced by the pusher and returns to the original uncompressed state. Therefore, when the washer 131 is released from the pressure of the pusher 130, the position of the front end 131a remains unchanged while the position of the base end 131b moves further towards the base end side (see figure). Figure 8A (See the figure below). In this specification, when the washer 131 is released from the push of the pusher 130, the increase in the thickness of the washer 131 caused by the washer 131 returning from the compressed state to the uncompressed state is called the pushback amount L1.

[0071] (Pushback amount L2)

[0072] In the event of a blocked supply path (giving an anomaly), such as Figure 8B As shown in the figure above, the gasket 131 stops in contact with the liquid medicine retained at the front end of the liquid medicine container 110. At this time, the gasket 131 is in a compressed state, and the pressure applied to the liquid medicine retained in the liquid medicine container 110 and the supply path is higher than the pressure at the base end 131b of the gasket 131. When the gasket 131 is released from the pushing of the pushing member 130 due to the retraction of the pushing member 130, the thickness of the gasket 131 increases as it returns from a compressed state to a non-compressed state, and the increased pressure applied to the liquid medicine retained in the liquid medicine container 110 and the supply path causes the gasket 131 to move towards the base end (see figure). Figure 8B(See the diagram below). In this specification, when the gasket 131 is released from the pressure of the pusher 130, the increase in the thickness of the gasket 131 due to its return from a compressed state to a non-compressed state is referred to as the push-back amount L1 when the drug supply is completed. Furthermore, the amount of movement of the gasket 131 caused by the increased pressure applied to the drug container 110 and the supply path is referred to as the push-back amount L3. Moreover, the total amount of the push-back amounts L1 and L3 is referred to as the push-back amount L2.

[0073] Furthermore, the values ​​of the pushback amount L1 and L2 of the washer 131 can also be preset. In addition, the values ​​of the first rotation number and the second rotation number of the motor 141 can also be preset.

[0074] Then, the control unit 150 starts timing (S100), based on the return amount L of the mating pusher 130 (refer to...). Figure 8A The motor 141 is started in reverse at a preset speed (the speed at which the pusher retracts) by setting the operating time or the third rotation number of the motor 141 (S101). At this time, the control unit 150 sets the return amount L of the pusher 130.

[0075] The return amount L of the pusher 130 refers to the distance that the pusher 130 moves from its current position to the base end side by causing the motor 141 to reverse. It is set with consideration of the push-back amounts L1 and L2 of the washer 131.

[0076] In this embodiment, the return amount L of the pusher 130 is set to be greater than the pushback amount L2 of the washer 131.

[0077] When the base end 131b of the washer 131 is released from the push of the pusher 130, regardless of whether the application is completed or an abnormality has occurred, it will not move from the stop position toward the base end side by a greater amount than the push-back L2. Therefore, when the return amount L is set to a value greater than the push-back amount L2, the control unit 150 can retract the front end of the pusher 130 to a position closer to the base end side than the position of the pushed-back washer 131 base end 131b.

[0078] Furthermore, the values ​​of the return amount L of the pressing member 130 and the operating time or third rotation number of the motor 141 corresponding to the return amount L of the pressing member 130 can also be preset. The operating time of the motor 141 corresponding to the return amount L of the pressing member 130 refers to the time required for the pressing member 130 to move by the return amount L at the pressing member retraction speed. The third rotation number of the motor 141 corresponding to the return amount L of the pressing member 130 refers to the number of rotations of the motor 141 required to move the pressing member 130 by the return amount L. In addition, if it is not possible to set the retraction speed of the pressing member to be faster than the moving speed of the base end 131b of the washer 131, the base end 131b of the washer 131 may come into contact with the pressing member 130, making it impossible to accurately measure the operating time of the motor 141 corresponding to the return amount L of the pressing member 130. Therefore, the third rotation number corresponding to the return amount L of the pressing member 130 is used.

[0079] Furthermore, the control unit 150 starts the motor 141 in reverse and determines whether the pusher 130 is retracted by the action confirmation function that confirms the operation status of the motor 141 based on the detection result of the rotation detection unit 144 (S102).

[0080] If the pusher 130 does not retract (motor 141 does not operate) (S102: No), the control unit 150 determines that the motor 141 has malfunctioned. Furthermore, the control unit 150 determines that the medication delivery is abnormal due to the malfunction of the motor 141 (S103). Additionally, if the pusher 130 does not retract, a malfunction of the motor 141 and / or the reduction mechanism 142 is suspected, but in the following description, it will be explained as a malfunction of the motor 141.

[0081] On the other hand, when the pusher 130 retracts (motor 141 operates) (S102: Yes), the control unit 150 determines that an abnormality in the delivery has occurred due to a reason other than a malfunction of the motor 141, or that the delivery of the medicine has been completed.

[0082] In this way, after confirming that the motor 141 has stopped, the control unit 150 reverses and starts the motor 141 and determines whether the pusher 130 has retracted (step S102), thereby confirming the operating status of the motor 141 and determining whether an abnormality in the dispensing of the medicine has occurred due to a malfunction of the motor 141. As a result, the medicine dispensing device 100 can more accurately detect the dispensing status of the medicine.

[0083] Then, when the motor 141 is activated (S102: Yes), the control unit 150 determines whether time T1 (equivalent to "prescribed time") has elapsed since the motor 141 started to reverse (S104).

[0084] The time T1 is set to be longer than the longer of either the time it takes for the base end 131b of the washer 131 to complete the movement of the push-back amount L1 or the time it takes to complete the movement of the push-back amount L2 after being released from the push of the push member 130. Furthermore, the value of time T1 can be set during the confirmation operation or preset.

[0085] Then, if the control unit 150 has not yet elapsed time T1 since the start of the reverse rotation of the motor 141 (S104: No), it repeats step S104.

[0086] On the other hand, when time T1 has elapsed since the motor 141 reversed (S104: Yes), the control unit 150 causes the motor 141 to rotate forward (S105). At this time, the control unit 150 uses a speed calculation function to make the motor 141 rotate at a preset speed (push member forward speed). In addition, the control unit 150 measures the fourth number of rotations of the motor 141 during the forward rotation period using an operation confirmation function and a current value measurement function. Figure 9 The P4 (hereinafter referred to as the rotation number P4) and the current value A1 are shown.

[0087] Then, the control unit 150 determines whether the current value A1 of the motor 141 measured by the current value measurement function is less than the threshold A (S106). Furthermore, the threshold A refers to the upper limit current value used to propel the push member 130 forward in an unloaded state (the state where the push member 130 is not in contact with the washer 131). When the motor 141 rotates at the push member forward speed in an unloaded state, if the push member 130 touches the washer 131, the load on the motor 141 will increase, and in order to maintain the push member forward speed, the current flowing to the motor 141 will become greater than the upper limit current value.

[0088] When the current value A1 of the motor 141 is less than the threshold A (S106: Yes), the control unit 150 determines that the pushing member 130 has not yet touched the washer 131 (the washer 131 is stopped in front compared to the position of the pushing member 130), and repeats step S106 to make the pushing member 130 move forward further.

[0089] On the other hand, if the current value A1 of the motor 141 is equal to or greater than the threshold A (S106: No), the control unit 150 determines that the front end of the push member 130 has touched the base end 131b of the washer 131, and stops the push member 130 (stops the operation of the motor 141), and proceeds to step S107.

[0090] Then, when the current value A1 measured by the current value measurement function exceeds the threshold A (S106: No), the control unit 150 determines whether the rotation number P4 measured by the action confirmation function is higher than the rotation number P (S107). Furthermore, the determination in step S106 can also be made using the rotational speed of the motor 141. The control unit 150 can also determine whether the rotation number P4 measured by the action confirmation function is higher than the rotation number P when the measured rotational speed is lower than a predetermined rotational speed (threshold) used to determine contact. Furthermore, the rotation number P4 refers to the value of the number of rotations of the motor 141 from the start of forward rotation in step S105 until the operation of the motor 141 stops when step S106 is negative. The rotation number P is the value obtained by subtracting the first rotation number from the third rotation number. Here, the third rotation number is the rotation number of the motor 141 corresponding to the return amount L of the push member 130, which refers to the number of rotations of the motor 141 required to move the push member 130 by the return amount L. The first rotation number is the rotation number of the motor 141 corresponding to the push-back amount L1 of the washer 131, which refers to the number of rotations of the motor 141 required to move the push member 130 by the push-back amount L1.

[0091] If the rotation number P4 of the motor 141 is equal to or less than the rotation number P (S107: No), the control unit 150 determines that the movement of the washer 131 when released from the pressure of the pusher 130 is equal to or greater than the pushback amount L1. Therefore, the control unit 150 determines that the washer 131 has been pushed back beyond the distance from the compressed state to the uncompressed state, and determines that an abnormality in the delivery of the medicine has occurred due to the blockage of the supply path (S108). In addition, the control unit 150 can determine the position of the washer 131 that is hitting the pusher 130 based on the rotation number P4 of the motor 141, and can predict the degree of blockage of the supply path.

[0092] On the other hand, if the number of rotations P4 of the motor 141 is greater than the number of rotations P (S107: Yes), the control unit 150 determines that the amount of movement of the washer 131 when it is released from the pressure of the pusher 130 is less than the amount of pushback L1. Therefore, the control unit 150 determines that the washer 131 has not been pushed back to the distance when it returns from the compressed state to the uncompressed state, and determines that the administration of the medicine is completed (S109).

[0093] Furthermore, the medication dispensing device 100 may also include a notification unit (not shown) that notifies the user when an abnormality in medication dispensing is detected. The notification unit may be, for example, an LED located on the housing 120 of the medication dispensing device 100. The notification unit can notify the user of the abnormality by illuminating or flashing the LED. Alternatively, the notification unit may be a speaker located inside the housing 120 of the medication dispensing device 100, and the control unit 150 can also notify the user of the abnormality by activating the speaker. Additionally, the notification unit can wirelessly notify an external portable terminal or computer of the abnormality in medication dispensing.

[0094] As described above, the liquid dispensing device 100 of this embodiment includes: a pushing member 130 that pushes out the liquid from a liquid container 110 filled with liquid; a drive mechanism 140 that causes the pushing member 130 to move forward and backward relative to the front opening of the liquid container 110; and a control unit 150 that controls the operation of the drive mechanism 140. In this liquid dispensing device, the drive mechanism 140 includes a motor 141 that generates a driving force for moving the pushing member 130 forward and backward, and a rotation detection unit 144 that detects the rotation of the motor 141. The control unit 150 has an operation confirmation function that confirms the operation status of the motor 141 based on the detection result of the rotation detection unit 144. After the control unit 150 confirms that the motor 141 has stopped through the operation confirmation function, it reverses the motor 141 and starts it up, and determines whether the pushing member 130 has moved backward.

[0095] According to the above-described liquid dispensing device 100, after confirming that the motor 141 has stopped, the control unit 150 reverses and starts the motor 141 and determines whether the pusher 130 has retracted. This allows the control unit to confirm the operating status of the motor 141 and determine whether an abnormality in liquid dispensing has occurred due to a malfunction of the motor 141. As a result, the liquid dispensing device 100 can more accurately detect the liquid dispensing status.

[0096] Furthermore, the medicine dispensing device 100 has a washer 131 that can slide along the inner wall 110a of the medicine container 110 and separate from the pusher 130. The medicine in the medicine container 110 is pushed out by the front end of the pusher 130 pushing the washer 131. With this structure, when the pusher 130 is retracted, the washer 131 separates from the pusher 130.

[0097] Furthermore, after the pusher 130 is retracted by reversing the motor 141, the control unit 150 reverses the motor 141 and then rotates the motor 141 forward to determine whether the pusher 130 has touched the washer 131. With this structure, the medicine dispensing device 100 can more accurately detect the dispensing status of the medicine.

[0098] Additionally, the liquid dispensing device 100 includes: a liquid container 110 filled with liquid medicine; a gasket 131 slidable along the inner wall 110a of the liquid container 110; a pressing member 130 that presses against the gasket 131; a drive mechanism 140 that causes the pressing member 130 to move forward and backward relative to the front opening of the liquid container 110; and a control unit 150 that controls the operation of the drive mechanism 140. In this liquid dispensing device, the drive mechanism 140 has the ability to generate force to press against the gasket 131. The control unit 150 includes a motor 141 that provides forward and reverse driving force, a rotation detection unit 144 that detects the rotation of the motor 141, and an operation confirmation function that confirms the operating status of the motor 141 based on the detection result of the rotation detection unit 144. After confirming that the motor 141 has stopped through the operation confirmation function, the control unit 150 reverses the motor 141 to retract the push member 130, and then immediately reverses the motor 141 to rotate forward, determining whether the push member 130 has touched the washer 131. With this structure, the medicine dispensing device 100 can more accurately detect the medicine dispensing status.

[0099] Furthermore, the control unit 150 determines whether the pressing member 130 has contacted the washer 131 based on the current value A1 flowing to the motor 141 or the rotational speed of the motor 141. When the control unit 150 makes the determination based on the current value A1 flowing to the motor 141, it can determine whether the current value A1 is lower than the upper limit current value (threshold A) for advancing the pressing member 130 in an unloaded state (the state where the pressing member 130 is not in contact with the washer 131). In addition, when the control unit 150 makes the determination based on the rotational speed of the motor 141, it can determine whether the measured rotational speed is lower than a predetermined rotational speed for determining contact. As a result, the medicine dispensing device 100 can more accurately detect the medicine dispensing status.

[0100] Furthermore, the control unit 150 determines whether the medication in the medicine container 110 has been dispensed successfully or whether a blockage has occurred based on whether the pusher 130 has touched the washer 131. Thus, the medication dispensing device 100 can more accurately detect the medication dispensing status.

[0101] Furthermore, the control unit 150 waits for a specified time T1 after reversing the motor 141 before reversing it to rotate forward. As a result, the medicine dispensing device 100 can more accurately detect the dispensing status of the medicine.

[0102] Furthermore, time T1 (the specified time) is the time from when the motor 141 reverses until the movement of the washer 131 stops. Therefore, the medicine dispensing device 100 can more accurately detect the dispensing status of the medicine.

[0103] Furthermore, if the pushing member does not retract even when the motor is reversed, it is determined that the motor has malfunctioned. Therefore, the medicine dispensing device 100 can more accurately detect the dispensing status of the medicine.

[0104] <Second Implementation>

[0105] Next, refer to Figure 10 The confirmation operation of the control unit 150 in the second embodiment will be explained. Figure 10 This is a flowchart of the operation of the control unit 150 in the second embodiment.

[0106] First, the control unit 150 sets the first rotation number and the second rotation number of the motor 141 corresponding to the pushback amount L1 and L2 of the washer 131. In addition, the values ​​of the pushback amount L1 and L2 or the values ​​of the first rotation number and the second rotation number can also be preset.

[0107] The control unit 150 starts timing (S200) and, based on the second return amount of the pressing member 130 and the operating time or fifth rotation number of the motor 141 set accordingly, reverses the motor 141 at a preset pressing member retraction speed, so that the position of the pressing member 130 moves towards the base end side by a second return amount relative to the current stop position (S201). At this time, the control unit 150 sets the second return amount of the pressing member 130.

[0108] The second return amount of the pusher 130 is set to be greater than the pushback amount L1 of the washer 131 and less than the pushback amount L2. Therefore, in the event of a blockage in the supply path, the pushback amount of the washer 131 is greater than the second return amount of the pusher 130; and in the event that the medication has been dispensed, the pushback amount of the washer 131 is less than the second return amount of the pusher 130.

[0109] Furthermore, the values ​​of the second return amount of the pressing member 130 and the operating time or fifth rotation number of the motor 141 corresponding to the second return amount of the pressing member 130 can also be preset. The operating time of the motor 141 corresponding to the second return amount of the pressing member 130 refers to the time required for the pressing member 130 to move the second return amount at the pressing member retraction speed. The fifth rotation number of the motor 141 corresponding to the second return amount of the pressing member 130 refers to the number of rotations of the motor 141 required to move the pressing member 130 by the second return amount. In addition, if it is not possible to set the retraction speed of the pressing member to be faster than the moving speed of the base end 131b of the washer 131, the base end 131b of the washer 131 may come into contact with the pressing member 130, making it impossible to accurately measure the operating time of the motor 141 corresponding to the second return amount of the pressing member 130. Therefore, the fifth rotation number corresponding to the second return amount of the pressing member 130 can be used.

[0110] Furthermore, the control unit 150 starts the motor 141 in reverse and determines whether the pusher 130 is retracted by the action confirmation function that confirms the operation status of the motor 141 based on the detection result of the rotation detection unit 144 (S202).

[0111] If the pusher 130 does not retract (motor 141 does not operate) (S202: No), the control unit 150 determines that the motor 141 has malfunctioned. Furthermore, the control unit 150 determines that the medication delivery is abnormal due to the malfunction of the motor 141 (S203).

[0112] On the other hand, when the motor 141 is in operation (S202: Yes), the control unit 150 determines that an abnormality in the administration has occurred due to reasons other than a malfunction of the motor 141, or that the administration of the medicine has been completed.

[0113] In this way, after confirming that the motor 141 has stopped, the control unit 150 reverses the motor 141 and determines whether the pusher 130 has retracted (step S202). This allows the control unit to confirm the operating status of the motor 141 and determine whether the dispensing of the medicine has been abnormal due to a malfunction of the motor 141.

[0114] Furthermore, when the motor 141 is in motion (S202: Yes), the control unit 150 determines whether time T2 (equivalent to "prescribed time") has elapsed since the motor 141 began to reverse (S204).

[0115] Time T2 is set to be longer than the longer of the time it takes for the base end 131b of the washer 131 to complete the movement of the push-back amount L1 or L2 after being released from the push of the pusher 130. In addition, the value of time T2 can be set during the confirmation operation or preset.

[0116] Then, if the control unit 150 has not yet elapsed time T2 since the start of the reverse rotation of the motor 141 (S204: No), it repeats step S204.

[0117] On the other hand, when time T2 has elapsed since the motor 141 was reversed (S204: Yes), the control unit 150 causes the motor 141 to rotate forward (S205). At this time, the control unit 150 uses the speed calculation function to make the motor 141 rotate at a preset speed. In addition, since the second return amount of the push member 130 is set to a value that is greater than the push-back amount L1 and less than the push-back amount L2, and the time T2 is set to be longer than the longer of the time it takes for the base end 131b of the washer 131 released from the push of the push member 130 to complete the movement of the push-back amount L1 or the push-back amount L2, when the supply path is blocked, the base end 131b of the washer 131 contacts the front end of the push member 130 at the time point when time T2 has elapsed since the motor 141 was reversed; while when the supply is completed, the base end 131b of the washer 131 does not contact the front end of the push member 130. In addition, the control unit 150 uses the current value measurement function to measure the current value B1 immediately after the motor 141 is turned forward.

[0118] Then, the control unit 150 determines whether the current value B1 of the motor 141 is less than the threshold A (S206). In addition, the rotational speed of the motor 141 can also be measured, and it can be determined whether the rotational speed is less than a predetermined rotational speed (threshold) used to determine contact.

[0119] If the current value B1 of the motor 141 (the current value immediately after the motor 141 reverses) is equal to or greater than the threshold A (S206: No), the control unit 150 determines that the pushing member 130 is in contact with the washer 131. Therefore, the control unit 150 determines that the amount of movement (distance) of the washer 131 when it is released from the pushing of the pushing member 130 is equal to the second return amount. Moreover, the control unit 150 determines that the washer 131 has been pushed back more than the distance when it returns from the compressed state to the uncompressed state, and determines that an abnormality in the delivery of the medicine has occurred due to the blockage of the supply path (S207).

[0120] On the other hand, if the current value B1 of the motor 141 (the current value immediately after the motor 141 reverses) is less than the threshold A (S206: Yes), the control unit 150 determines that the pushing member 130 has not touched the washer 131 that is stopped in the medicine container 110. Therefore, the control unit 150 determines that the amount of movement (distance) of the washer 131 when it is released from the pushing member 130 is less than the second return amount. Moreover, the control unit 150 determines that the washer 131 has not been pushed back more than the distance when it returns from the compressed state to the uncompressed state, and determines that the medicine delivery has been completed (S208).

[0121] As explained above, the control unit 150 of the second embodiment has a current measurement function that measures the current flowing to the motor 141. The control unit 150 sets a second return amount that causes the pusher 130 to retract after confirming that the motor 141 has stopped, an operating time of the motor 141 corresponding to the second return amount, and a time T2 (predetermined time) that is longer than the operating time of the motor 141. After time T2 has elapsed since the motor 141 was reversed, the control unit 150 causes the motor 141 to rotate forward, and determines whether the current value B1 measured by the current measurement function immediately after the motor 141 is turned forward is lower than a threshold A (a predetermined upper limit current value), or whether the rotational speed measured by the encoder is lower than a threshold (a predetermined upper limit rotational speed). Thus, the control unit 150 can determine whether the pusher 130 has touched the washer 131, and whether an abnormality in the delivery of the medicine has occurred due to a blockage in the supply path.

[0122] Furthermore, the washer 131, which is disposed at the front end of the pusher 130 and can slide along the inner wall of the liquid container 110, has its second return amount set to a value greater than the push-back amount L1 and less than the push-back amount L2. Therefore, when the supply path is blocked, the washer 131 contacts the front end of the pusher 130 immediately before the pusher 130 moves forward after retracting. Therefore, the control unit 150 can determine whether an abnormality in liquid delivery has occurred due to a blockage in the supply path by judging whether the current value B1 of the motor 141 is lower than the threshold A. In addition, by setting the second return amount of the pusher 130 to be less than the push-back amount L2, the protrusion of the pusher 130 from the liquid container 110 due to the retraction of the pusher 130 will be smaller, thus making the size of the liquid delivery device 100 more compact.

[0123] Furthermore, in the event of supply path obstruction, the pushback amount is based on the increase in thickness of gasket 131 from a compressed state to an uncompressed state. Figure 8B The amount of pushback L1 shown (as indicated) may vary depending on the viscosity of the liquid used or the material of the gasket 131, even after the liquid application is complete (see reference). Figure 8A The two are not consistent. In this case, a pushback amount based on the increase in thickness of gasket 131 from compressed to uncompressed state can be set separately in the case of supply path blockage, and the total amount of pushback amount L3 and the separately set pushback amount is taken as pushback amount L2.

[0124] The above describes the drug delivery device of the present invention through embodiments, but the present invention is not limited to the described structures, and can be appropriately modified based on the claims.

[0125] This application is based on Japanese Patent Application No. 2020-54542, filed on March 25, 2020, the disclosure of which is incorporated herein by reference in its entirety.

[0126] Explanation of reference numerals in the attached figures

[0127] 10. Drug delivery system,

[0128] 100 Drug delivery device,

[0129] 110. Medicine container

[0130] 110a The inner wall of the liquid medicine container,

[0131] 110b The inner wall of the front side of the liquid medicine container,

[0132] 130 push-fit component,

[0133] 131 Washer

[0134] 140 drive mechanism,

[0135] 141 motors

[0136] 144 Rotary Detection Unit

[0137] 144a Optical Interruptor

[0138] 144b slotted plate,

[0139] 150 Control Department

[0140] A. Threshold (upper limit current value),

[0141] The current values ​​of motors A1 and B1.

[0142] H body surface,

[0143] L represents the return value.

[0144] L1, L2, L3 pushback amount,

[0145] T1 and T2 are time intervals.

Claims

1. A drug delivery device, comprising: A container filled with medicinal liquid; A pusher that pushes the liquid medicine out of the liquid medicine container; A gasket, disposed at the front end of the pusher, is capable of sliding along the inner wall of the liquid container and separating from the pusher; A drive mechanism that causes the pusher to move forward and backward relative to the front opening of the liquid medicine container; and The control unit controls the operation of the drive mechanism. The characteristic of this drug delivery device is that... The liquid medicine in the medicine container is pushed out by pushing the washer with the front end of the pusher. The pushing member separates from the washer and retracts. When the gasket is released from the pushing force of the pusher, the increase in the thickness of the gasket due to its return from a compressed state to a non-compressed state is defined as the pushback amount L1. The amount of movement of the gasket caused by the increased pressure applied to the liquid medicine remaining in the liquid medicine container and supply path is defined as the pushback amount L3. The total amount of the pushback amount L1 and the pushback amount L3 is defined as the pushback amount L2. The drive mechanism includes a motor that generates a driving force for moving the pusher forward and backward, and a rotation detection unit that detects the rotation of the motor. The control unit has an operation confirmation function that confirms the operating status of the motor based on the detection results of the rotation detection unit. The control unit is configured such that, After confirming that the motor has stopped through the action confirmation function, the motor is restarted in reverse, and it is determined whether the pushing member has retracted. If the motor does not reverse, it is considered an abnormality. In the case of motor reversal, after the pusher has moved backward a distance L from its current position towards the base end due to the motor reversal, the motor is rotated forward, and it is determined whether the pusher has touched the washer based on the current flowing to the motor or the motor's rotational speed. If the pushing member comes into contact with the washer, it is determined that a blockage has occurred. If the pushing member does not touch the washer, it is determined that the medication in the medication container has been dispensed. The return amount L is greater than the pushback amount L1 and less than the pushback amount L2.

2. The drug delivery device according to claim 1, characterized in that, If the control unit determines that the motor has malfunctioned even when the motor is started in reverse and the pushing member does not retract, the motor has malfunctioned.

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