Medicine cartridge and medicine injection device

Abstract

This medicine cartridge is used upon being incorporated in a medicine injection device, and is provided with: a syringe that accommodates a medicine, a case that accommodates the syringe in a state in which the syringe can move in the front-rear direction, a cap that is attached to the front end part of the case, and a spring that is provided between the syringe and the case and constantly impels the syringe rearward.

Description

Drug cartridge and drug injection device

[0001] The present invention relates to a drug cartridge and a drug injection device.

[0002] Conventionally, pharmaceutical injection devices that are used by users (i.e., patients) to inject medicine themselves have been known (see Patent Document 1). Such pharmaceutical injection devices are used with a disposable cartridge attached. The cartridge contains a syringe filled with medicine.

[0003] Special table 2014-516634 publication

[0004] However, since the drug cartridge and drug injection device described above are carried around by users and used in a variety of locations, it is desirable for the drug cartridge and drug injection device to be highly portable.

[0005] The present invention has been made in view of the above circumstances, and has as its object to provide a drug cartridge and a drug injection device that are highly portable.

[0006] One aspect of the drug cartridge according to the present invention is a drug cartridge that is incorporated into a drug injection device for use, and includes: a syringe that contains a drug; a case that contains the syringe in a state that allows the syringe to move back and forth; a cap attached to the front end of the case; and a spring that is provided between the syringe and the case and constantly urges the syringe backward.

[0007] One aspect of the drug injection device according to the present invention comprises a case having a storage section that stores a drug cartridge that holds a syringe, a motor housed in the case, and an operating section housed in the case, wherein the operating section performs a needle insertion action that moves the syringe back and forth, an injection action that moves the piston of the syringe forward, and a locking action that locks the drug cartridge, based on the power of the motor.

[0008] According to the present invention, it is possible to provide a drug cartridge and a drug injection device that are highly portable.

[0009] FIG. 1 is a perspective view of a drug cartridge and a drug injection device according to Embodiment 1. FIG. 2 is a block diagram showing the configuration of the drug injection device. FIG. 3 is an exploded perspective view of the drug cartridge. FIG. 4 is a cross-sectional view of the drug cartridge. FIG. 5 is a cross-sectional view illustrating the drug cartridge assembly process. FIG. 6 is a cross-sectional view illustrating the drug cartridge assembly process. FIG. 7 is a cross-sectional view of the drug cartridge. FIG. 8 is a perspective view showing a partial configuration of the drug injection device. FIG. 9 is a perspective view showing a partial configuration of the drug injection device. FIG. 10A is a cross-sectional view of the drug injection device in a basic state. FIG. 10B is a cross-sectional view of the drug injection device after a locking operation. FIG. 10C is a cross-sectional view of the drug injection device after a needle insertion operation. FIG. 10D is a cross-sectional view of the drug injection device after an injection operation. FIG. 10E is a cross-sectional view of the drug injection device after needle removal is complete (immediately after needle removal). FIG. 10F is a cross-sectional view of the drug injection device after the needle removal operation (after all needle removal operations are completed). FIG. 11A is an enlarged cross-sectional view showing the device engagement part, locking engagement part, and latch cover when the drug injection device is in an unlocked state. FIG. 11B is an enlarged cross-sectional view showing the state of the device engaging portion, locking engaging portion, and latch cover when the pharmaceutical injection device is in the locked state. FIG. 11C is a partial cross-sectional view of the pharmaceutical injection device in its basic state. FIG. 12 is a flowchart showing the self-injection process. FIG. 13 is a flowchart showing the cartridge mounting process. FIG. 14 is a flowchart showing the process including the automatic needle insertion process and the automatic injection process. FIG. 15 is a flowchart showing the process including the automatic needle removal process. FIG. 16 is a diagram showing an example of a modified pharmaceutical injection device.

[0010] The pharmaceutical cartridge and pharmaceutical injection device according to the present invention will now be described with reference to the drawings, in which like reference numerals are used to designate like components.

[0011] [Embodiment] A drug cartridge and a drug injection device according to an embodiment of the present invention will be described with reference to Figures 1 to 15 .

[0012] 1 is a perspective view of a drug cartridge 1 and a drug injection device 2 according to an embodiment of the present invention. The drug cartridge 1 and the drug injection device 2 can be collectively considered to be a drug injection system.

[0013] The drug cartridge 1 and drug injection device 2 are used when a user injects themselves. Hereinafter, the act of a user injecting themselves will be referred to as "self-injection." First, an overview of how the drug cartridge 1 and drug injection device 2 are used will be described.

[0014] When self-injecting, the user loads the drug cartridge 1 into the drug injection device 2. The drug cartridge 1 contains a syringe 13 (see FIG. 3) filled with a drug.

[0015] When the drug cartridge 1 is attached to the drug injection device 2, the drug cartridge 1 is locked to the drug injection device 2 so that the drug cartridge 1 does not come off the drug injection device 2. This operation is referred to as the locking operation of the drug injection device 2.

[0016] Next, the user brings the skin detection unit 201 (see FIG. 1 ), which is located at the tip of the pharmaceutical injection device 2, into contact with their own skin (i.e., their skin). In this state, the user presses the injection button 202 on the pharmaceutical injection device 2.

[0017] When the injection button 202 is pressed while the skin detection unit 201 is in contact with the user's skin (i.e., the skin), the pharmaceutical injection device 2 performs an operation to insert the needle 131 (see FIG. 4 ) of the syringe 13 into the user. The operation of inserting the needle 131 of the syringe 13 into the user is referred to as the needle insertion operation of the pharmaceutical injection device 2.

[0018] When the needle 131 of the syringe 13 is inserted into the user, the pharmaceutical injection device 2 performs an operation to inject the pharmaceutical loaded into the syringe 13 into the user. The operation of injecting the pharmaceutical loaded into the syringe 13 into the user is referred to as the injection operation of the pharmaceutical injection device 2.

[0019] Then, once the injection operation is complete, the pharmaceutical injection device 2 performs an operation to remove the needle 131 (see FIG. 4 ) of the syringe 13 from the user. The operation of removing the needle 131 of the syringe 13 from the user is referred to as the needle removal operation of the pharmaceutical injection device 2.

[0020] During the needle retraction operation, the pharmaceutical injection device 2 unlocks the pharmaceutical cartridge 1 from the pharmaceutical injection device 2. The operation of unlocking the pharmaceutical cartridge 1 from the pharmaceutical injection device 2 is referred to as the pharmaceutical injection device 2 unlocking operation.

[0021] The pharmaceutical injection device 2 configured as above performs the locking operation, needle insertion operation, injection operation, needle withdrawal operation, and lock release operation described above using the power of a motor 41 (see FIG. 8).

[0022] The following describes the specific configuration of the drug cartridge 1 and the drug injection device 2. In describing the structure of the drug cartridge 1 and the drug injection device 2, a Cartesian coordinate system (X, Y, Z) shown in each figure is used.

[0023] The X direction corresponds to the front-to-rear direction of the drug cartridge 1 and the drug injection device 2. The positive side of the X direction corresponds to the front side of the drug cartridge 1 and the drug injection device 2. The positive side of the X direction is also the direction in which the syringe 13 moves during the needle insertion operation of the drug injection device 2. Therefore, the positive side of the X direction is sometimes referred to as the needle insertion direction.

[0024] The negative side of the X direction coincides with the rear side of the drug cartridge 1 and the pharmaceutical injection device 2. The negative side of the X direction is also the direction in which the syringe 13 moves during the needle withdrawal operation of the pharmaceutical injection device 2. Therefore, the negative side of the X direction is sometimes referred to as the needle withdrawal direction.

[0025] The Y direction corresponds to the left-right and width directions of the drug cartridge 1 and the drug injection device 2. The + side of the Y direction corresponds to the right side when the drug cartridge 1 and the drug injection device 2 are viewed from the front. The - side of the Y direction corresponds to the left side when the drug cartridge 1 and the drug injection device 2 are viewed from the front.

[0026] The Z direction corresponds to the up-down direction (thickness direction) of the drug cartridge 1 and the drug injection device 2. The + side of the Z direction corresponds to the upper side of the drug cartridge 1 and the drug injection device 2. The - side of the Z direction corresponds to the lower side of the drug cartridge 1 and the drug injection device 2.

[0027] (Drug Cartridge) First, the specific configuration of the drug cartridge 1 will be described with reference to Figures 3 to 7. The drug cartridge 1 is a disposable cartridge that is replaced after each self-injection. During self-injection, the drug cartridge 1 is used while housed in a cartridge housing 301 (see Figure 10A) of the drug injection device 2, which will be described later.

[0028] Fig. 3 is an exploded perspective view of the medicine cartridge 1. Fig. 4 is a cross-sectional view of the medicine cartridge 1 cut along the XZ plane and viewed from the +Y direction side. Figs. 5 and 6 are cross-sectional views showing the medicine cartridge 1 in the middle of an assembly process.

[0029] 7 is a cross-sectional view of the drug cartridge 1 cut along the XY plane, viewed from the +Z direction. The drug cartridge 1 shown in FIGS. 4 and 7 is in a state prior to being attached to the drug injection device 2.

[0030] 4 and 7 is referred to as the basic state of the drug cartridge 1. In addition, the positions of the components constituting the drug cartridge 1 in the basic state of the drug cartridge 1 are referred to as the basic positions of the components.

[0031] 3, the drug cartridge 1 includes a case 10, a cap 11, a spring 12, and a syringe 13. The case 10, the cap 11, the spring 12, and the syringe 13 are assembled in the state shown in FIGS.

[0032] (Case) As shown in Fig. 3, the case 10 has a cylindrical shape extending in the front-rear direction. The case 10 has a pair of flat surfaces 100a, 100b facing each other. The pair of flat surfaces 100a, 100b face each other in the up-down direction.

[0033] The drug cartridge 1 can be stored in the cartridge storage section 301 of the drug injection device 2 with the flat surface 100a of the case 10 facing upward. The drug cartridge 1 can also be stored in the cartridge storage section 301 of the drug injection device 2 with the flat surface 100b of the case 10 facing upward.

[0034] (RFID Tag) The case 10 has an RFID tag 101 on one of the pair of flat surfaces 100a, 100b, the flat surface 100a. The RFID tag 101 may also be provided on the flat surface 100b.

[0035] The RFID tag 101 is capable of transmitting and receiving information through short-range communication using radio waves. The RFID tag 101 may store information (e.g., type and amount) about the drug filled in the syringe 13. The RFID tag 101 may also store information such as the manufacturing date and / or expiration date of the syringe 13.

[0036] The RFID tag 101 is covered with a sealing member (not shown). The RFID tag 101 may be a type that allows information to be added or rewritten from the outside. The information stored in the RFID tag 101 may be protected by a tamper-proof function.

[0037] The information stored in such an RFID tag 101 is read by the pharmaceutical injection device 2 (specifically, the RFID antenna 205 (see FIG. 2 )) when the pharmaceutical cartridge 1 is attached to the pharmaceutical injection device 2. Note that an NFC tag can also be used instead of the RFID tag 101.

[0038] The case 10 has a pair of slits 102a, 102b (see FIGS. 3 and 4) extending in the front-rear direction on each of the pair of flat surfaces 100a, 100b. The slits 102a, 102b each limit the distance that the syringe 13 can move in the front-rear direction. In other words, the syringe 13 can move in the front-rear direction by a distance corresponding to the length of the slits 102a, 102b in the front-rear direction.

[0039] Rear end portions 102c (see FIG. 4) of slits 102a and 102b each engage with the rear end portion (specifically, flange portion 130a) of syringe 13 (specifically, syringe body 130) in the basic state of drug cartridge 1. Rear end portions 102c of slits 102a and 102b each correspond to an example of a second case side engaging portion.

[0040] That is, when drug cartridge 1 is in the basic state, slits 102a and 102b restrict the rearward movement of syringe 13 based on the engagement with syringe 13.

[0041] Furthermore, slits 102a and 102b prevent syringe 13 from slipping out rearward when drug cartridge 1 is in the basic state. That is, slits 102a and 102b also function to prevent syringe 13 from slipping out.

[0042] Furthermore, front end portions 102d of the slits 102a and 102b restrict forward movement of the syringe 13 based on engagement with the syringe 13. The front end portions 102d of the slits 102a and 102b each correspond to an example of a third case side engagement portion.

[0043] 4, the flange portion 130a of the syringe 13 comes into contact with the front end portions 102d of the slits 102a and 102b. The front end portions 102d of the slits 102a and 102b restrict the forward movement of the syringe 13.

[0044] The case 10 also has a locking engagement portion 103 (see FIG. 3 ). The locking engagement portion 103 is configured with a plurality of (four in this embodiment) through-holes that penetrate the case 10 in the radial direction.

[0045] In this embodiment, the locking engagement portions 103 are provided at positions spaced apart at equal intervals in the circumferential direction of the case 10 .

[0046] The locking engagement portion 103 is provided on the rear end side of the medicine cartridge 1 at a position corresponding to the front ends of the slits 102a and 102b in the front-rear direction. The positions of the locking engagement portions 103 in the front-rear direction are the same. Note that the locking engagement portion 103 and the front ends of the slits 102a and 102b do not necessarily have to be provided at corresponding positions.

[0047] This locking engagement portion 103 engages with the holding portion 30 (specifically, the device-side engagement portion 302) of the drug injection device 2 when the drug cartridge 1 is attached to the drug injection device 2 (hereinafter, sometimes referred to as the "attached state of the drug cartridge 1").

[0048] The case 10 also has an engagement maintaining portion 104 at the front end of the inner circumferential surface. The engagement maintaining portion 104 prevents the needle shield 133 of the syringe 13 from disengaging from the cap 11 when the cap 11 is removed from the case 10. The engagement maintaining portion 104 is an example of a diameter expansion preventing portion.

[0049] The engagement maintaining portion 104 is configured by a plurality of ribs (four in this embodiment) provided on the inner peripheral surface of the case 10. The plurality of ribs are spaced at equal intervals in the circumferential direction. Note that some of the plurality of ribs are not shown in FIG. 7. The function of the engagement maintaining portion 104 will be described later. The configuration of the engagement maintaining portion 104 is not limited to ribs.

[0050] The case 10 also has a spring receiving portion 105 (see FIG. 4) on its inner peripheral surface. The spring receiving portion 105 corresponds to an example of a first case side engaging portion. The spring receiving portion 105 is configured by the rear end surfaces of multiple ribs extending in the front-rear direction. The spring receiving portion 105 is a portion that abuts against the front end of the spring 12. The configuration of the spring receiving portion 105 is not limited to ribs.

[0051] (Cap) The cap 11 is attached to the front end of the case 10. The cap 11 is cylindrical and has open ends in the front-rear direction.

[0052] Specifically, the cap 11 has a large-diameter cylindrical portion 110 and a small-diameter cylindrical portion 111. The large-diameter cylindrical portion 110 is provided in the front half of the cap 11. The small-diameter cylindrical portion 111 is provided in the rear half of the cap 11. The large-diameter cylindrical portion 110 and the small-diameter cylindrical portion 111 are connected by a circular ring-shaped step portion.

[0053] The cap 11 has a pair of cap-side engaging portions 112a, 112b (see FIG. 3) on the small-diameter cylindrical portion 111. The cap-side engaging portions 112a, 112b are each arm-shaped and extend in the front-rear direction. The cap-side engaging portions 112a and 112b face each other in the radial direction of the small-diameter cylindrical portion 111.

[0054] The cap side engaging portions 112a and 112b each elastically deform in the radial direction of the small diameter cylindrical portion 111. When the cap side engaging portions 112a and 112b elastically deform in the radial direction of the small diameter cylindrical portion 111, the distance between the cap side engaging portions 112a and 112b changes.

[0055] Each of the cap side engaging portions 112a and 112b has a claw portion at the rear end thereof, which engages with the needle shield 133 of the syringe 13 when the drug cartridge 1 is in the basic state.

[0056] (Spring) The spring 12 is a coil spring. The spring 12 is housed in the case 10. A syringe 13 is inserted into the spring 12. The central axis of the spring 12 coincides with the central axes of the case 10 and the syringe 13.

[0057] The rear end of spring 12 abuts against flange portion 130a of syringe 13 when drug cartridge 1 is in the basic state. The front end of spring 12 abuts against spring receiving portion 105 (see FIG. 4) of case 10 when drug cartridge 1 is in the basic state.

[0058] The spring 12 having the above-described configuration is compressed between the syringe 13 and the case 10 in the basic state of the drug cartridge 1. In this state, the spring 12 constantly biases the syringe 13 rearward.

[0059] (Syringe) The syringe 13 has a syringe body 130 , a needle 131 , a syringe-side piston 132 , and a needle shield 133 .

[0060] The syringe body 130 is cylindrical and has a storage portion for storing a medicine. The syringe body 130 has a flange portion 130a at the rear end. The flange portion 130a corresponds to an example of a syringe-side engaging portion.

[0061] The flange portion 130 a has a circular ring shape that extends from the outer peripheral surface of the syringe body 130 outward in the radial direction of the syringe body 130 .

[0062] The rear end surface of flange portion 130a engages with rear end portions 102c of slits 102a and 102b in case 10 when drug cartridge 1 is in the basic state. The front end surface of flange portion 130a abuts against the rear end portion of spring 12 when drug cartridge 1 is in the basic state.

[0063] The flange portion 130a is constantly biased rearward by the spring 12. The rearward movement of the flange portion 130a is restricted by the rear end portions 102c of the slits 102a and 102b in the case 10.

[0064] The needle 131 is provided at the front end of the syringe body 130. The needle shield 133 is attached to the front end of the syringe body 130 so as to cover the needle 131.

[0065] The syringe piston 132 is housed in a housing portion of the syringe body 130. The syringe piston 132 is movable in the front-to-rear direction within the syringe body 130. A drug is filled in front of the syringe piston 132 in the housing portion of the syringe body 130.

[0066] When the syringe piston 132 moves forward with the needle shield 133 removed from the syringe body 130, the drug present in front of the syringe piston 132 in the syringe body 130 moves forward. The drug is then injected to the outside from the tip of the needle 131.

[0067] 5 to 7, a method for assembling the medicine cartridge 1 will be described. The medicine cartridge 1 may be assembled manually by an operator or by an assembly device.

[0068] The following describes the procedure when an operator performs the method of assembling the medicine cartridge 1. When the method of assembling the medicine cartridge 1 is performed using an assembly device, the following description may be interpreted appropriately.

[0069] First, as shown in Fig. 5, the worker places the cap 11 on the front end of the case 10. In this state, the cap 11 is not fixed to the case 10. More specifically, the cap 11 is temporarily fixed by lightly press-fitting the small-diameter cylindrical portion 111 into the engagement maintaining portion 104 of the case 10.

[0070] Next, as shown in Figure 5, the worker inserts the spring 12 into the case 10 through the opening on the rear side of the case 10. In this state, the spring 12 is in a free state. The rear end of the spring 12 is located rearward of the rear end of the case 10. The front end of the spring 12 abuts against the spring receiving portion 105 (see Figure 4).

[0071] 5, the rear end of spring 12 may be engaged with rear end portions 102c of slits 102a, 102b in case 10. In this state, spring 12 may be compressed. Such a configuration contributes to improving the efficiency of the assembly work of medicine cartridge 1.

[0072] Next, as shown in Fig. 5, the operator inserts the syringe 13 into the case 10 from the opening at the rear of the case 10. At this time, the syringe 13 is inserted into the spring 12 from the rear. In this state, the operator supports the cap 11 from below to prevent the cap 11 from coming off the case 10.

[0073] Then, the operator moves the syringe 13 downward from the position shown in Fig. 5. The syringe 13 moves downward while contracting the spring 12. As a result, the syringe 13 moves to the position shown in Fig. 6.

[0074] Next, the operator moves the syringe 13 further downward from the state shown in Fig. 6. As a result, the flange portion 130a of the syringe 13 is press-fitted into the inner circumferential surface of the rear end portion of the case 10, and the syringe 13 moves downward.

[0075] 7 (i.e., the home position), flange portion 130a of syringe 13 engages with slits 102a and 102b of case 10. This completes the assembly of drug cartridge 1.

[0076] When the syringe 13 moves from the position shown in Fig. 5 to the position shown in Fig. 6, the needle shield 133 of the syringe 13 is inserted from the rear into the small-diameter cylindrical portion 111 of the cap 11. At this time, the needle shield 133 is inserted into the small-diameter cylindrical portion 111 while widening the cap-side engaging portions 112a and 112b, as shown in Fig. 6.

[0077] In other words, when the needle shield 133 enters the small diameter cylindrical portion 111 of the cap 11 , the cap side engagement portions 112 a and 112 b are each elastically deformed outward in the radial direction of the small diameter cylindrical portion 111 .

[0078] In this manner, in the case of this embodiment, when the needle shield 133 enters the small diameter cylindrical portion 111 of the cap 11 , the cap side engagement portions 112 a and 112 b expand in diameter to allow the needle shield 133 to enter the small diameter cylindrical portion 111 .

[0079] Specifically, when the cap 11 is attached to the front end of the case 10, there is an expansion allowance space 113 (see Figure 6) between the cap side engagement portions 112a, 112b and the inner surface of the case 10, which allows the cap side engagement portions 112a, 112b to expand in diameter.

[0080] In this manner, in the present embodiment, the presence of the diameter expansion allowing space 113 allows the needle shield 133 to enter the small diameter cylindrical portion 111 of the cap 11. The diameter expansion allowing space 113 corresponds to an example of a diameter expansion allowing portion.

[0081] When the needle shield 133 advances to the position shown in FIG. 7, the cap side engaging portions 112 a and 112 b elastically deform to reduce their diameter, and the claw portions of the cap side engaging portions 112 a and 112 b engage with the rear end of the needle shield 133 .

[0082] In the basic state shown in FIG. 7, the needle shield 133 and the cap side engaging portions 112a, 112b are engaged with an engaging force greater than the degree to which the cap 11 does not come off the case 10 due to gravity.

[0083] The engagement force means the force required for the user to pull the cap 11 downward to separate the cap 11 from the case 10 in the basic state shown in FIG.

[0084] In this embodiment, the engagement force between the cap side engagement portions 112 a and 112 b and the needle shield 133 in the basic state shown in FIG. 7 is set to be greater than the spring force of the spring 12 .

[0085] That is, when the user pulls the cap 11 downward in the basic state shown in FIG. 7, the spring 12 contracts while the engagement between the cap side engagement portions 112a, 112b and the needle shield 133 is maintained.

[0086] Therefore, when the cap 11 is pulled downward in the basic state shown in FIG. 7, the entire syringe 13 moves forward while the engagement between the cap side engagement portions 112a, 112b and the needle shield 133 is maintained.

[0087] Here, we will explain the operation of the drug cartridge 1 when the cap 11 is removed from the case 10 from the basic state shown in Figure 7. Note that during self-injection, when the cap 11 is removed from the case 10, the drug cartridge 1 is attached to the drug injection device 2.

[0088] 7, the user pulls the cap 11 forward. This moves the cap 11 forward. Because the cap-side engagement portions 112a and 112b of the cap 11 are engaged with the needle shield 133, the needle shield 133 also moves forward.

[0089] 7, the engagement force between the cap side engagement portions 112a, 112b and the needle shield 133 is set to be greater than the spring force of the spring 12. Therefore, when the cap 11 moves forward, the spring 12 contracts, and the entire syringe 13 moves forward together with the cap 11.

[0090] The syringe 13 then moves to a position where the flange portion 130a abuts against the front end portions 102d of the slits 102a and 102b. Although not shown, this state is referred to as a first state of the syringe 13 and the cap 11. The positions of the syringe 13 and the cap 11 in the first state are also referred to as first positions of the syringe 13 and the cap 11.

[0091] In the first state of the syringe 13 and the cap 11, the cap side engaging portions 112a, 112b are located inside the engagement maintaining portion 104 of the case 10. In this state, the engagement maintaining portion 104 prevents the cap side engaging portions 112a, 112b from expanding in diameter.

[0092] In other words, in the first state of the syringe 13 and the cap 11, the cap side engaging portions 112a, 112b cannot expand in diameter to release the engagement between the needle shield 133 and the cap side engaging portions 112a, 112b.

[0093] The user further pulls the cap 11 forward from the first state of the syringe 13 and the cap 11. Then, the cap 11 moves forward while the engagement maintaining portion 104 restrains the cap side engagement portions 112a and 112b from expanding in diameter.

[0094] In this state, the syringe body 130 cannot move forward because its forward movement is restricted by the front end portions 102d of the slits 102a and 102b. As a result, the needle shield 133 detaches from the syringe body 130.

[0095] Then, the needle shield 133 moves forward together with the cap 11, and the cap 11 and the needle shield 133 are detached from the drug cartridge 1. When the needle shield 133 is detached from the syringe body 130, the syringe body 130 moves rearward based on the biasing force of the spring 12 and returns to the basic position shown in FIG.

[0096] When the cap 11 is detached from the syringe body 130, the needle 131 is housed in the case 10 as shown in Fig. 7. In other words, in the state shown in Fig. 7, the needle 131 is not exposed to the outside from the tip of the case 10. This configuration contributes to improved safety.

[0097] (Drug Injection Device) Next, the configuration of the pharmaceutical injection device 2 will be described with reference to Figures 8 to 15. Figures 8 and 9 are perspective views of only a portion of the configuration of the pharmaceutical injection device 2. Figures 10A to 10F are cross-sectional views of the pharmaceutical injection device 2 cut along the XY plane, viewed from the +Z direction.

[0098] Specifically, Figure 10A is a cross-sectional view of the pharmaceutical injection device 2 in its basic state. Note that in Figure 10A, a pharmaceutical cartridge 1 is inserted into the pharmaceutical injection device 2. However, the pharmaceutical cartridge 1 is not locked to the pharmaceutical injection device 2. The state of the pharmaceutical injection device 2 shown in Figure 10A is sometimes referred to as the unlocked state.

[0099] 10B is a cross-sectional view of the pharmaceutical injection device 2 after the locking operation. In other words, Fig. 10B is a cross-sectional view showing the locked state of the pharmaceutical injection device 2. In the state shown in Fig. 10B, the pharmaceutical cartridge 1 is locked to the pharmaceutical injection device 2.

[0100] 10C is a cross-sectional view of the pharmaceutical injection device 2 after needle insertion. In other words, FIG. 10C is a cross-sectional view of the pharmaceutical injection device 2 after needle insertion is complete.

[0101] 10D is a cross-sectional view of the pharmaceutical injection device 2 after the injection operation. In other words, FIG. 10D is a cross-sectional view showing the pharmaceutical injection device 2 in a state where injection has been completed.

[0102] 10E is a cross-sectional view of the pharmaceutical injection device 2 after needle removal (in other words, immediately after needle removal). The state of the pharmaceutical injection device 2 shown in FIG. 10E differs from the state of the pharmaceutical injection device 2 shown in FIG. 10A in that the piston 55 has not yet fully returned.

[0103] 10F is a cross-sectional view of the pharmaceutical injection device 2 after all needle withdrawal operations have been completed. The state of the pharmaceutical injection device 2 shown in FIG. 10F is the same basic state as the state of the pharmaceutical injection device 2 shown in FIG. 10A.

[0104] The pharmaceutical injection device 2 performs various operations during self-injection. Specifically, the pharmaceutical injection device 2 performs a locking operation, a needle insertion operation, an injection operation, a needle removal operation, and an unlocking operation.

[0105] The locking operation is an operation of locking the drug cartridge 1. The needle insertion operation is an operation of inserting the needle 131 of the syringe 13 into the user. The injection operation is an operation of injecting the drug in the syringe 13 into the user.

[0106] The needle withdrawal operation is an operation of withdrawing the needle 131 of the syringe 13 from the user. The lock release operation is an operation of releasing the lock on the medicine cartridge 1.

[0107] Furthermore, the pharmaceutical injection device 2 can assume a state corresponding to each of the operations described above. The state in which the pharmaceutical cartridge 1 is not attached to the pharmaceutical injection device 2 is referred to as the basic state of the pharmaceutical injection device 2. The state in which the pharmaceutical cartridge 1 is attached to the pharmaceutical injection device 2 and is not locked to the pharmaceutical injection device 2 (i.e., the state shown in FIG. 10A ) is also the basic state of the pharmaceutical injection device 2.

[0108] Furthermore, the state of the pharmaceutical injection device 2 after the needle insertion operation and before the injection operation is referred to as the needle insertion completed state of the pharmaceutical injection device 2. Furthermore, the state of the pharmaceutical injection device 2 after the injection operation and before the needle removal operation is referred to as the injection completed state of the pharmaceutical injection device 2.

[0109] Furthermore, the state of the pharmaceutical injection device 2 after the needle withdrawal operation (the state shown in FIG. 10E) is referred to as the state of the pharmaceutical injection device 2 after needle withdrawal is complete.

[0110] The pharmaceutical injection device 2 mainly comprises a case section 3 , a drive section 4 , and an actuation section 5 .

[0111] (Case section) The case section 3 houses each of the elements that make up the pharmaceutical injection device 2. The case section 3 has a holding section 30 (see FIGS. 8 and 10A) that holds the pharmaceutical cartridge 1. The holding section 30 is an example of a first locking member and is cylindrical. The holding section 30 is provided in the left half of the case section 3.

[0112] The space surrounded by the holding portion 30 constitutes a part of a cartridge housing portion 301 that houses the medicine cartridge 1. The cartridge housing portion 301 is a cylindrical space that extends in the front-rear direction.

[0113] The holding portion 30 has device-side engaging portions 302 (see FIGS. 8, 11A, and 11B) that engage with the locking engaging portions 103 (see FIGS. 3, 11A, and 11B) of the medicine cartridge 1. The number of device-side engaging portions 302 is the same as the number of locking engaging portions 103.

[0114] When the drug cartridge 1 is attached to the drug injection device 2, the device-side engaging portion 302 engages with the locking engaging portion 103 (see Figure 3) from the outside of the drug cartridge 1 (specifically, the outside in the radial direction).

[0115] The case portion 3 also has an inner case element 31. The inner case element 31 is cylindrical. A slider 51 (see FIG. 10A ), which will be described later, is inserted into the inner case element 31. In other words, the inner case element 31 is disposed so as to cover the outer peripheral surface of the slider 51.

[0116] The inner case element 31 has guide protrusions 310 (see Figures 8 and 9) on its inner circumferential surface. Note that the inner case element 31 is omitted in Figures 8 and 9. In Figures 8 and 9, the guide protrusions 310 are indicated by hatched black circles.

[0117] The guide protrusion 310 protrudes inward in the radial direction of the inner case element 31 from the inner peripheral surface of the inner case element 31. The guide protrusion 310 is always inserted into a spiral guide groove 510 (see FIGS. 8 and 9 ) provided in the slider 51.

[0118] When the slider 51 rotates, the guide grooves 510 of the slider 51 are guided by the guide protrusions 310, and the slider 51 moves in the front-rear direction.

[0119] In the basic state of the pharmaceutical injection device 2, the guide protrusion 310 is located at the start point 511 (i.e., the front end) of the guide groove 510. In the basic state of the pharmaceutical injection device 2, the position of the guide protrusion 310 in the guide groove 510 is referred to as the start point position of the guide protrusion 310.

[0120] When the pharmaceutical injection device 2 is in the locked state, the guide protrusion 310 is located at a position (hereinafter referred to as the "locked position") that is slightly moved from the start point 511 (i.e., the front end) of the guide groove 510 toward the end point 512. When the pharmaceutical injection device 2 is in the locked state, the position of the guide protrusion 310 in the guide groove 510 is referred to as the locked position of the guide protrusion 310.

[0121] The guide protrusion 310 is located at the end point 512 (i.e., the rear end) of the guide groove 510 when the pharmaceutical injection device 2 is in the needle insertion complete state. The position of the guide protrusion 310 in the guide groove 510 when the pharmaceutical injection device 2 is in the needle insertion complete state is referred to as the end point position of the guide protrusion 310.

[0122] In reality, the guide protrusions 310 do not move in the front-rear direction. The relative positional relationship between the guide protrusions 310 and the guide grooves 510 changes as the slider 51 moves relative to the inner case element 31.

[0123] In this way, the inner case element 31 (in other words, the case portion 3) may be regarded as a member that guides the movement of the slider 51 in the front-rear direction.

[0124] The cartridge accommodating section 301 has an opening at the front end. The drug cartridge 1 is inserted into the cartridge accommodating section 301 through the opening of the cartridge accommodating section 301. Note that the opening of the cartridge accommodating section 301 may be closed by, for example, a cover member (not shown) when the drug cartridge 1 is not inserted.

[0125] The case 3 may be made of a single member or may be made of multiple members combined with each other. In the following description, the term "supported by the case 3" refers not only to a configuration directly supported by the case 3, but also to a configuration indirectly supported by the case 3 via another member.

[0126] (Drive Unit) The drive unit 4 drives the operating unit 5, which will be described later. The drive unit 4 is disposed in the right half of the case unit 3. The right half of the case unit 3 is referred to as a first storage unit. On the other hand, the left half of the case unit 3 is referred to as a second storage unit.

[0127] The drive unit 4 includes a power supply unit 40 , a motor 41 , a speed reducer 42 , and a transmission unit 43 .

[0128] (Power Supply Unit) The power supply unit 40 is supported by the case unit 3. The power supply unit 40 is, for example, a rechargeable lithium ion battery. The power supply unit 40 supplies power to each element that makes up the pharmaceutical injection device 2. The power supply unit 40 is located in the middle of the first storage unit in the front-to-rear direction.

[0129] (Motor) The motor 41 is supported by the case 3. The motor 41 is, for example, a DC motor. The motor 41 is configured as a single motor. In other words, the pharmaceutical injection device 2 has only one motor 41 as its drive source. This configuration contributes to the miniaturization of the pharmaceutical injection device 2.

[0130] The motor 41 operates based on the power supplied from the power supply unit 40 under the control of the control unit 204. The output (i.e., rotation) of the motor 41 is transmitted to the speed reducer 42, which will be described later. The rotation direction of the motor 41 is controlled by the control unit 204. The motor 41 is disposed rearward of the power supply unit 40 in the first housing unit.

[0131] The motor 41 is provided with a position detection unit 200. The position detection unit 200 is, for example, a rotary encoder. The position detection unit 200 is provided on the rotation shaft of the motor 41 or on a member that rotates together with the rotation shaft.

[0132] The position detection unit 200 sends the detection value to the control unit 204. The control unit 204 acquires information about the operating state of the motor 41 (specifically, the rotation direction and amount of rotation of the motor 41) based on the detection value of the position detection unit 200.

[0133] Then, the control unit 204 acquires information about the state of the actuator 5 based on the acquired information about the operating state of the motor 41. The information about the state of the actuator 5 may include information about the position of each element constituting the actuator 5 and / or information about the movement distance.

[0134] (Speed ​​reduction unit) The speed reduction unit 42 is supported by the case unit 3. The speed reduction unit 42 reduces the speed of the output (i.e., rotation) of the motor 41 and transmits it to the transmission unit 43, which will be described later. The speed reduction unit 42 is configured by, for example, a planetary gear mechanism. Note that the speed reduction unit 42 is not limited to a planetary gear mechanism and may be various types of reducers.

[0135] The speed reducer 42 is disposed in the first housing portion rearward of the motor 41. The speed reducer 42 and the motor 41 are disposed on the same straight line parallel to the front-rear direction.

[0136] (Transmission Unit) The transmission unit 43 is supported by the case unit 3. The transmission unit 43 is connected to the speed reducer 42. The transmission unit 43 transmits the power (i.e., rotation) of the motor 41 transmitted from the speed reducer 42 to the operating unit 5 (specifically, the feed screw 50), which will be described later. The transmission unit 43 has a first rotation transmission member 430 and a second rotation transmission member 431.

[0137] The first rotation transmission member 430 and the second rotation transmission member 431 each have teeth on their outer circumferential surfaces. The first rotation transmission member 430 is disposed at the rear end of the first housing portion. The first rotation transmission member 430 is fixed to the output shaft of the speed reducer 42. Therefore, the first rotation transmission member 430 rotates based on the power transmitted from the speed reducer 42.

[0138] The second rotation transmission member 431 is disposed at the rear end of the second housing portion. The teeth of the second rotation transmission member 431 and the teeth of the first rotation transmission member 430 mesh with each other. The second rotation transmission member 431 is connected to the operating portion 5 (specifically, the feed screw 50), which will be described later.

[0139] The first rotation transmission member 430 and the second rotation transmission member 431 each rotate about a central axis parallel to the front-rear direction, and are prevented from moving in the front-rear direction.

[0140] When the first rotation transmission member 430 rotates based on the power (i.e., rotation) transmitted from the speed reducer 42, the second rotation transmission member 431 rotates in synchronization with the first rotation transmission member 430. When the second rotation transmission member 431 rotates, the operating unit 5 is operated.

[0141] (Actuator) Next, the configuration of the actuator 5 will be described. The actuator 5 operates based on the power (i.e., rotation) transmitted from the driver 4. Specifically, the actuator 5 performs a locking operation, a needle insertion operation, an injection operation, a needle removal operation, and an unlocking operation based on the power of the driver 4. The operation of the actuator 5 will be described later.

[0142] The actuation portion 5 is disposed in the second housing portion of the case portion 3. As described above, the second housing portion is the left half portion of the case portion 3.

[0143] The actuating portion 5 mainly includes a feed screw 50 , a slider 51 , a torque limiter 52 , a latch 53 , a latch cover 54 , and a piston 55 .

[0144] (Feed Screw) The feed screw 50 is supported by the case portion 3. The feed screw 50 is a shaft-shaped member. The feed screw 50 is arranged parallel to the front-rear direction. The feed screw 50 is rotatable around a central axis parallel to the front-rear direction.

[0145] The feed screw 50 is also movable in the front-to-rear direction. The feed screw 50 moves in the front-to-rear direction in conjunction with the front-to-rear movement of the slider 51. In other words, the feed screw 50 moves in sync with the slider 51. The amount of front-to-rear movement of the feed screw 50 is the same as the amount of front-to-rear movement of the slider 51.

[0146] The feed screw 50 is connected to the drive unit 4. Specifically, the feed screw 50 has a base portion 501 and a screw portion 502. The front end of the base portion 501 is connected to the rear end of the screw portion 502. The screw portion 502 has a male thread portion on its outer circumferential surface.

[0147] The feed screw 50 is connected to the second rotation transmission member 431 in the transmission unit 43 of the drive unit 4. Specifically, the rear end of the base portion 501 is inserted into the second rotation transmission member 431.

[0148] The rear end of the feed screw 50 (specifically, the base portion 501) is configured, for example, by a D-cut portion having a D-shaped cross section. The inner peripheral surface of the second rotation transmission member 431 is shaped to fit the outer peripheral surface of the rear end of the feed screw 50. The rear end of the feed screw 50 and the second rotation transmission member 431 are engaged in a state in which torque (in other words, rotation) can be transmitted.

[0149] The front end of the feed screw 50 (specifically, the screw portion 502) is connected to a piston 55 (described later). The male thread of the screw portion 502 and the piston 55 are threadedly engaged with each other.

[0150] The feed screw 50 having this configuration rotates based on the rotation of the second rotation transmission member 431. In other words, the rotation of the second rotation transmission member 431 is transmitted to the feed screw 50.

[0151] The feed screw 50 also moves in the front-rear direction in accordance with the front-rear movement of a slider 51 (described later). The operation of the feed screw 50 will be described later.

[0152] (Slider and Torque Limiter) The slider 51 is supported by the inner case element 31 of the case portion 3. The slider 51 corresponds to an example of a first moving member. As shown in Fig. 8, the slider 51 is cylindrical. The slider 51 is disposed with its central axis parallel to the front-rear direction.

[0153] A feed screw 50 is inserted into the slider 51. The central axis of the slider 51 and the central axis of the feed screw 50 are arranged on the same straight line.

[0154] The slider 51 has a spiral guide groove 510 (see FIGS. 8 and 9) on its outer circumferential surface. The guide groove 510 extends from a start point 511 at the front end to an end point 512 at the rear end along the outer circumferential surface of the slider 51.

[0155] The guide groove 510 engages with the guide protrusion 310 (see FIGS. 8 and 9) of the inner case element 31 of the case portion 3 .

[0156] 8 and 9, the guide protrusions 310 are indicated by hatched black circles, and the inner case element 31 is omitted from the drawings.

[0157] The slider 51 moves in the front-to-rear direction in response to its own rotation. The slider 51 moves in the front-to-rear direction as the guide groove 510 is guided by the guide protrusion 310. The amount of movement of the slider 51 in the front-to-rear direction (in other words, the stroke) is equal to the distance in the front-to-rear direction between the start point 511 and the end point 512 of the guide groove 510.

[0158] When the slider 51 is at the rear end of the stroke, the guide protrusion 310 is located at the start point 511 (i.e., the front end) of the guide groove 510. On the other hand, when the slider 51 is at the front end of the stroke, the guide protrusion 310 is located at the end point 512 (i.e., the rear end) of the guide groove 510.

[0159] The slider 51 is connected to the feed screw 50 via a torque limiter 52. That is, the torque limiter 52 is provided between the feed screw 50 and the slider 51. The central axis of the slider 51 and the central axis of the torque limiter 52 are arranged on the same straight line.

[0160] The torque limiter 52 switches between a state in which the rotation of the feed screw 50 is transmitted to the slider 51 (hereinafter sometimes referred to as the "torque limiter transmission state") and a state in which the rotation of the feed screw 50 is not transmitted to the slider 51 (hereinafter sometimes referred to as the "torque limiter non-transmission state").

[0161] The torque limiter 52 is an example of a switching mechanism that switches between the needle insertion operation and the injection operation of the pharmaceutical injection device 2. The needle insertion operation and injection operation of the pharmaceutical injection device 2 are described below.

[0162] Specifically, the torque limiter 52 is in a torque transmission state when the torque acting on the torque limiter 52 is equal to or less than a predetermined value. On the other hand, the torque limiter 52 is in a torque non-transmission state when the torque acting on the torque limiter 52 is greater than the predetermined value.

[0163] In this embodiment, the torque acting on the torque limiter 52 may be considered as the torque acting on the torque limiter 52 from the feed screw 50 .

[0164] The configuration of the torque limiter 52 may be substantially the same as that of a commonly known torque limiter, and therefore, a description of the specific configuration of the torque limiter 52 will be omitted.

[0165] The torque limiter 52 is cylindrical. The feed screw 50 is inserted into the inner peripheral surface of the torque limiter 52. The torque limiter 52 and the feed screw 50 are engaged with each other in a state in which power (i.e., rotation) can be transmitted.

[0166] The torque limiter 52 and the feed screw 50 are engaged in a state in which they can move synchronously in the front-rear direction. That is, the torque limiter 52 and the feed screw 50 move in the front-rear direction at the same time.

[0167] The outer peripheral surface of the torque limiter 52 is inserted into the inner peripheral surface of the slider 51. In other words, the slider 51 is provided so as to cover the outer peripheral surface of the torque limiter 52.

[0168] The torque limiter 52 and the slider 51 are engaged in a state in which power (i.e., rotation) can be transmitted. The torque limiter 52 and the slider 51 are also engaged in a state in which they can move synchronously in the front-to-rear direction. In other words, the torque limiter 52 and the slider 51 move in the front-to-rear direction simultaneously. The operation of the slider 51 and the torque limiter 52 will be described later.

[0169] (Latch) As shown in Fig. 9, the latch 53 is cylindrical. The latch 53 is connected to the front end of the slider 51. The feed screw 50 and the piston 55 are inserted through the latch 53.

[0170] The latch 53 has a through-hole 531 (see FIG. 11C) at a predetermined position in the front-rear direction. The through-hole 531 penetrates the latch 53 in the radial direction of the latch 53. The through-hole 531 is provided on the outer surface of the latch 53 on the negative side in the Z direction.

[0171] When the pharmaceutical injection device 2 is in its basic state (the state shown in FIGS. 10A, 10F, and 11C), the through-hole 531 faces the detected portion 550 of the piston 55 (see FIGS. 10A, 10F, and 11C) in the radial direction of the latch 53.

[0172] Furthermore, when the pharmaceutical injection device 2 is in its basic state (the state shown in FIGS. 10A, 10F, and 11C), the through-hole 531 faces a basic position detector 209 (described below) in the radial direction of the latch 53.

[0173] The latch 53 is movable in the front-rear direction together with the slider 51. However, the rotation of the latch 53 is restricted based on the engagement with the case portion 3. Therefore, the latch 53 does not rotate but moves in the front-rear direction together with the slider 51.

[0174] Specifically, the rear end of the latch 53 is inserted into the front end of the slider 51. In other words, the end of the latch 53 is covered by the front end of the slider 51.

[0175] The outer peripheral surface of the rear end of the latch 53 engages with the inner peripheral surface of the front end of the slider 51. Therefore, when the slider 51 moves in the front-to-rear direction, the latch 53 moves together with the slider 51 based on the engagement between the latch 53 and the slider 51 in the front-to-rear direction.

[0176] The front end of the latch 53 abuts against the rear end of the syringe 13 (specifically, the syringe body 130) when the drug cartridge 1 is attached to the drug injection device 2 (see FIG. 10B).

[0177] When the latch 53 moves forward during the needle insertion operation of the pharmaceutical injection device 2, the latch 53 pushes the syringe 13 (specifically, the syringe body 130) forward. In other words, the latch 53 is a component that moves the syringe 13 (specifically, the syringe body 130) forward during the needle insertion operation of the pharmaceutical injection device 2.

[0178] As a result of the slider 51 being moved forward by the motor 41 in this manner, the syringe 13 moves forward. From this perspective, the slider 51 can be regarded as an example of a first moving member. Furthermore, when the slider 51 is moved forward by the motor 41, the slider 51 and the latch 53 move forward. As a result, the syringe 13 moves forward. From this perspective, the latch 53 can also be regarded as an example of a first moving member. Alternatively, a member formed by combining the slider 51 and the latch 53 can be regarded as an example of a first moving member.

[0179] (Latch Cover) The latch cover 54 has a cylindrical shape as shown in Fig. 8. The latch cover 54 corresponds to an example of a second locking member. The feed screw 50 and the piston 55 are inserted through the latch cover 54.

[0180] The latch cover 54 is fixed to the latch 53. Therefore, the latch cover 54 moves in the front-rear direction together with the latch 53.

[0181] When the pharmaceutical injection device 2 is locked, the latch cover 54 moves forward together with the latch 53 and covers the device-side engagement part 302 of the holding part 30 of the case part 3 (see FIGS. 8 and 11B) from the outside.

[0182] In other words, when the locking operation of the pharmaceutical injection device 2 is complete, the latch cover 54 externally covers the engagement portion between the device-side engagement portion 302 and the locking engagement portion 103 of the pharmaceutical cartridge 1. The latch cover 54 then maintains the engagement state between the device-side engagement portion 302 and the locking engagement portion 103 of the pharmaceutical cartridge 1.

[0183] In this way, the latch cover 54 maintains the state (i.e., locked state) in which the drug cartridge 1 is locked to the drug injection device 2. The position in which the latch cover 54 covers the device-side engaging portion 302 from the outside (see FIG. 10B ) corresponds to an example of the first position.

[0184] The latch cover 54 has a detection target 541 (see FIG. 8) on its outer circumferential surface. The detection target 541 moves in the front-to-rear direction together with the latch cover 54. The detection target 541 is a part that is detected by a first detection unit 207 (see FIG. 2) and a second detection unit 208, which will be described later.

[0185] (Piston) The piston 55 is axially shaped as shown in Fig. 9. The piston 55 has a detection target 550 (see Figs. 10A and 11C) on its outer circumferential surface. The detection target 550 moves in the front-rear direction together with the piston 55.

[0186] The detected portion 550 is a portion that is detected by the base position detection unit 209 (see FIGS. 2 and 11C ), which will be described later. Specifically, the detected portion 550 may be a reflective sticker. The detected portion 550 (specifically, the reflective sticker) is annular and provided around the entire outer periphery of the piston 55.

[0187] If the detectable portion 550 (specifically, the reflective sticker) is annular, it is possible to make the detectable portion 550 face the basic position detection unit 209 regardless of the assembly direction of the piston 55 during the manufacturing process of the pharmaceutical injection device 2. This improves work efficiency.

[0188] The reflective sticker does not have to be annular, as long as it is provided at a position on the outer circumferential surface of the piston 55 that can face the home position detection unit 209.

[0189] The piston 55 is connected to the front end of the feed screw 50. Specifically, the front end of the feed screw 50 is inserted into the rear end of the piston 55.

[0190] The threaded portion provided on the rear end of the piston 55 is engaged with the threaded portion of the feed screw 50. The threaded portion of the piston 55 is a female threaded portion provided on the inner peripheral surface of the rear end of the piston 55. The threaded portion of the feed screw 50 is a male threaded portion provided on the outer peripheral surface of the feed screw 50.

[0191] The piston 55 is inserted through the latch 53. The rotation of the piston 55 is restricted by the latch 53. In other words, the piston 55 is prevented from rotating. The piston 55 is movable in the front-rear direction relative to the latch 53.

[0192] The piston 55 moves back and forth together with the feed screw 50. The piston 55 also moves back and forth in response to the rotation of the feed screw 50.

[0193] When the feed screw 50 rotates, the piston 55 moves forward based on the threaded engagement between the piston 55 and the feed screw 50. The operation of the piston 55 will be described later.

[0194] The feed screw 50 and the piston 55 are examples of a second moving member. The second moving member may be considered to be a member that rotates by a motor to push the pharmaceutical inside the syringe 13 forward during the injection operation of the pharmaceutical injection device 2.

[0195] (Other Components) The above are the main components of the pharmaceutical injection device 2. In addition to the components described above, the pharmaceutical injection device 2 also has, for example, a skin detection unit 201 (see FIG. 1 ). The skin detection unit 201 is located at the front end of the pharmaceutical injection device 2.

[0196] The skin detection unit 201 includes, for example, a capacitance touch sensor. The skin detection unit 201 detects that the user's skin (i.e., the human skin) has come into contact with the skin detection unit 201. The skin detection unit 201 sends the detection value to the control unit 204, which will be described later.

[0197] The pharmaceutical injection device 2 also has a plate-shaped main board 203 (see FIG. 2). Various electronic components are mounted on the main board 203. Furthermore, electronic components such as a power supply unit 40 and a motor 41 are connected to the main board 203.

[0198] In the present embodiment, the main board 203 is arranged parallel to the XZ plane. This configuration reduces the dimension in the left-right direction (i.e., the Y direction) of the pharmaceutical injection device 2. As a result, the pharmaceutical injection device 2 can be made more compact.

[0199] Furthermore, the main board 203 is equipped with a control unit 204 that provides overall control over the operation of the pharmaceutical injection device 2. The control unit 204 may actually be configured with a CPU, ROM, RAM, etc. connected via a bus, or may be configured with a one-chip LSI, etc.

[0200] The pharmaceutical injection device 2 also has an RFID antenna 205 (see FIG. 2). The RFID antenna 205 sends the acquired information to the control unit 204.

[0201] The drug injection device 2 has RFID antennas 205 at positions facing the flat surface 100a of the drug cartridge 1 (specifically, the case 10) and at positions facing the flat surface 100b of the drug cartridge 1 (specifically, the case 10) when the drug cartridge 1 is attached to the drug injection device 2.

[0202] In the case of the pharmaceutical injection device 2 of this embodiment, the pharmaceutical cartridge 1 can be attached to the pharmaceutical injection device 2 in either the state where the flat surface portion 100a is positioned on top or the state where the flat surface portion 100b is positioned on top.

[0203] Therefore, whether the flat portion 100a is positioned upward or downward, the RFID antenna 205 can read the information stored in the RFID tag 101 (i.e., information about the drug). This eliminates the need to provide two RFID tags 101 in the drug cartridge 1. This allows for a reduction in the cost of the drug cartridge 1.

[0204] The pharmaceutical injection device 2 also has a cartridge detection section 206 (see FIG. 1) in the cartridge detection region R1 (see FIG. 10A) at the front end of the cartridge storage section 301.

[0205] The cartridge detection unit 206 detects information indicating that the medicine cartridge 1 has been inserted into the cartridge housing unit 301. The cartridge detection unit 206 sends the detected value to the control unit 204.

[0206] In this embodiment, the cartridge detection unit 206 and the control unit 204 constitute a cartridge detection unit that detects that the medicine cartridge 1 is accommodated in the cartridge accommodating unit 301. It is to be noted that the cartridge detection unit 206 alone may detect that the medicine cartridge 1 is accommodated in the cartridge accommodating unit 301.

[0207] Additionally, the pharmaceutical injection device 2 has a first detection unit 207 (see FIGS. 2 and 10A) and a second detection unit 208 around the latch cover 54. The first detection unit 207 is located behind the second detection unit 208. The first detection unit 207 and the second detection unit 208 are located side by side in the front-to-rear direction.

[0208] The first detector 207 and second detector 208 send their detection values ​​to the controller 204. The controller 204 detects the state of the pharmaceutical injection device 2 based on the detection values ​​of the first detector 207 and second detector 208.

[0209] The control unit 204 detects that the pharmaceutical cartridge 1 is locked to the pharmaceutical injection device 2 based on the detection values ​​of the first detection unit 207 and the second detection unit 208 .

[0210] Furthermore, the control unit 204 detects that the pharmaceutical injection device 2 has finished the needle insertion operation based on the detection values ​​of the first detection unit 207 and the second detection unit 208 .

[0211] Furthermore, the control unit 204 detects that the pharmaceutical injection device 2 has finished retracting the needle based on the detection values ​​of the first detection unit 207 and the second detection unit 208 .

[0212] Specifically, the first detection unit 207 and the second detection unit 208 are each a sensor such as a photointerrupter. The detection values ​​of the first detection unit 207 and the second detection unit 208 differ depending on the position of the latch cover 54 (specifically, the detected portion 541).

[0213] When the first detector 207 and the second detector 208 detect the detection target portion 541 of the latch cover 54 , they send an ON signal to the controller 204 .

[0214] When the first detector 207 and the second detector 208 do not detect the detected portion 541 of the latch cover 54 , they send an OFF signal to the controller 204 .

[0215] 10A and 10E, neither the first detection unit 207 nor the second detection unit 208 faces the detected portion 541 of the latch cover 54. Therefore, both the first detection unit 207 and the second detection unit 208 send an OFF signal to the control unit 204.

[0216] 10B, the first detector 207 faces the detected portion 541 of the latch cover 54. Therefore, the first detector 207 sends an ON signal to the controller 204.

[0217] 10B, the second detector 208 does not face the detected portion 541 of the latch cover 54. Therefore, the second detector 208 sends an OFF signal to the controller 204.

[0218] 10C, when the pharmaceutical injection device 2 has completed needle insertion, the first detector 207 does not face the detected part 541 of the latch cover 54. Therefore, the first detector 207 sends an OFF signal to the controller 204.

[0219] 10C, the second detector 208 faces the detected part 541 of the latch cover 54. Therefore, the second detector 208 sends an ON signal to the controller 204.

[0220] Additionally, the pharmaceutical injection device 2 has a home position detection section 209 (see FIG. 2) in the home position detection region R2 (see FIGS. 10A and 11C) of the cartridge storage section 301.

[0221] 11C is an enlarged cross-sectional view of a portion of the pharmaceutical injection device 2 in the basic state that corresponds to the basic position detection region R2. The phase of the cross section of the pharmaceutical injection device 2 in Fig. 11C about the X axis (in other words, the position about the X axis) is different from the phase of the cross section of the pharmaceutical injection device 2 in Fig. 10A about the X axis (in other words, the position about the X axis).

[0222] The basic position detection unit 209 is a non-contact optical sensor (specifically, a photoreflector).

[0223] The home position detection unit 209 is supported directly or indirectly by the inner case element 31. As shown in Figure 11C, the home position detection unit 209 is located in a position opposite the detected portion 550 of the piston 55 with a gap therebetween when the piston 55 is in the home position (in other words, the home state of the pharmaceutical injection device 2).

[0224] In this state, the through-hole 531 of the latch 53 is present between the base position detection portion 209 and the detection target portion 550. Therefore, in the state shown in Fig. 11C, the base position detection portion 209 and the detection target portion 550 face each other in the radial direction of the latch 53 via the through-hole 531.

[0225] Furthermore, when the pharmaceutical injection device 2 is in a state other than the basic state, the detected part 550 is covered by the latch 53 due to the relative movement between the latch 53 and the piston 55. The basic position detection unit 209, detected part 550, and latch 53 are positioned such that the basic position detection unit 209 can detect the detected part 550 only when the pharmaceutical injection device 2 is in the basic state (the state shown in Figures 10A, 10F, and 11C).

[0226] 10A to 10F show a schematic representation of the positional relationship between the basic position detection unit 209, the detection target unit 550, and the through-hole 531 in each state of the pharmaceutical injection device 2.

[0227] The pharmaceutical injection device 2 shown in Figure 10A is in its base state. The pharmaceutical injection device 2 shown in Figure 10B is in its locked state. The pharmaceutical injection device 2 shown in Figure 10C is in its needle insertion state. The pharmaceutical injection device 2 shown in Figure 10D is in its injection completion state. The pharmaceutical injection device 2 shown in Figure 10E is in its needle removal completion state. The pharmaceutical injection device 2 shown in Figure 10F is in its base state. Details of each state of the pharmaceutical injection device 2 shown in Figures 10A to 10F will be provided below.

[0228] 10A and 10F, when the pharmaceutical injection device 2 is in its basic state, the basic position detection unit 209 and the detected part 550 face each other in the radial direction of the piston 55, via the through-hole 531. In other words, the basic position detection unit 209 can detect the detected part 550.

[0229] 10B, when the pharmaceutical injection device 2 is in the locked state, the latch 53 and piston 55 move further forward (in other words, toward the needle insertion direction) than in the basic state. In this state, the basic position detection unit 209 and the detected part 550 do not face each other in the radial direction of the piston 55. Therefore, the basic position detection unit 209 cannot detect the detected part 550.

[0230] 10C , when the pharmaceutical injection device 2 has completed needle insertion, the latch 53 and piston 55 move further forward (in other words, in the needle insertion direction) than when in the locked state. In this state, the home position detection unit 209 and the detected part 550 do not face each other in the radial direction of the piston 55. Therefore, the home position detection unit 209 cannot detect the detected part 550. In this state, the home position detection unit 209 is covered from the outside in the radial direction by the slider 51.

[0231] 10D , when the pharmaceutical injection device 2 is in the injection-completed state, the piston 55 moves further forward (in other words, in the needle insertion direction) than when needle insertion is complete. In this state, the home position detection unit 209 and the detected part 550 do not face each other in the radial direction of the piston 55. Therefore, the home position detection unit 209 cannot detect the detected part 550. In this state, the home position detection unit 209 is covered from the outside in the radial direction by the slider 51.

[0232] 10E, when the pharmaceutical injection device 2 is in the needle-removal state, the latch 53 moves further rearward (in other words, in the needle-removal direction) than when the injection is complete. In this state, the home position detection unit 209 and the detected part 550 do not face each other in the radial direction of the piston 55. Therefore, the home position detection unit 209 cannot detect the detected part 550. The operation of the pharmaceutical injection device 2 will be described in detail below.

[0233] As described above, the home position detection unit 209 detects that the piston 55 is located at the home position (specifically, the position shown in FIGS. 10A, 10F, and 11C).

[0234] In other words, the home position detection unit 209 detects that the pharmaceutical injection device 2 is in the home state ( FIGS. 10A, 10F, and 11C ). In other words, the home position detection unit 209 detects that the piston has returned completely after the pharmaceutical injection device 2 has finished retracting the needle. Based on the position of the piston 55, the home position detection unit 209 detects that the pharmaceutical injection device 2 has completed the entire series of injection operations.

[0235] Specifically, when the piston 55 is located at the home position, the detected portion 550 of the piston 55 (see FIGS. 10A and 11C ) faces the home position detection unit 209 via the through-hole 531 (see FIG. 11C ) of the latch 53. In this way, the home position detection unit 209 is provided at a position facing the detected portion 550 of the piston 55 when the piston 55 is located at the home position.

[0236] When the piston 55 is in the home position, the home position detection unit 209 detects the detection target portion 550 of the piston 55. The home position detection unit 209 sends the detected value to the control unit 204.

[0237] On the other hand, when the piston 55 is not positioned at the home position (for example, the state shown in FIG. 10C ), the detected part 550 of the piston 55 does not face the home position detection unit 209. Therefore, the home position detection unit 209 does not detect the detected part 550 of the piston 55.

[0238] The pharmaceutical injection device 2 also has a notification means for notifying the user of information. The notification means is, for example, configured as an LED light 211 provided on the top surface of the case 3. Specifically, the pharmaceutical injection device 2 may change the display mode of the LED light 211 depending on the type of pharmaceutical loaded into the pharmaceutical cartridge 1.

[0239] As one example, pharmaceutical injection device 2 may change the color of LED light 211 depending on the type of pharmaceutical loaded in pharmaceutical cartridge 1. By checking the color of LED light 211, the user can confirm that the pharmaceutical being administered is correct. This configuration contributes to improved safety during self-injection.

[0240] Furthermore, the pharmaceutical injection device 2 may change the display mode of the LED light 211 depending on the state of the pharmaceutical injection device 2 (in other words, the progress) during self-injection.

[0241] For example, the pharmaceutical injection device 2 turns off the LED light 211 when the pharmaceutical injection device 2 is in a state before use. Next, the pharmaceutical injection device 2 turns on the LED light 211 when the pharmaceutical cartridge 1 is attached to the pharmaceutical injection device 2 (in other words, when the pharmaceutical injection device 2 is locked).

[0242] Furthermore, when the pharmaceutical injection device 2 is preparing to administer (in other words, when the pharmaceutical injection device 2 is in a standby state), the LED light 211 is illuminated, just as when the pharmaceutical injection device 2 is locked.

[0243] Furthermore, when the pharmaceutical injection device 2 is ready to administer (in other words, when the pharmaceutical injection device 2 is ready to administer), the LED light 211 flashes slowly.

[0244] Furthermore, when the pharmaceutical injection device 2 is administering a pharmaceutical (in other words, when the pharmaceutical injection device 2 is in the administration state), the LED light 211 slowly flashes in a color different from that displayed when the pharmaceutical injection device 2 is in the administration-ready state. Note that when in the administration state, the pharmaceutical injection device 2 performs the needle insertion and injection operations of the pharmaceutical injection device 2, which are described below.

[0245] Furthermore, when administration of the drug by the drug injection device 2 is complete (in other words, when the drug injection device 2 has completed administration), the LED light 211 flashes slightly faster (for example, every 2 seconds) in the same color as the administration status of the drug injection device 2.

[0246] Furthermore, when the drug injection device 2 is performing the needle removal operation (in other words, when the drug injection device 2 is in the origin return state), the LED light 211 flashes in a color different from the color that indicates the drug injection device 2's administration-ready state and the drug injection device 2's administration state.

[0247] As described above, when self-injecting, the user can recognize the progress of self-injection by visually checking LED light 211.

[0248] Furthermore, if there is an error in the user's operation or the operation of the pharmaceutical injection device 2 during self-injection, the pharmaceutical injection device 2 may change the display mode of the LED light 211 depending on the type of error.

[0249] Specifically, when injection button 202 is pressed while the user's skin is not in contact with skin detection unit 201, pharmaceutical injection device 2 displays LED light 211 in a display mode indicating that the user's operation has resulted in an error. By looking at LED light 211, the user can recognize that there has been an error in their operation.

[0250] Furthermore, if the injection button 202 is not pressed when the pharmaceutical injection device 2 is ready for administration (in other words, the pharmaceutical injection device 2 is ready for administration), the pharmaceutical injection device 2 may change the display mode of the LED light 211 to prompt the user to press the injection button 202. At this time, the pharmaceutical injection device 2 may cause the LED light 211 to slowly flash orange.

[0251] Furthermore, the pharmaceutical injection device 2 may change the display mode of the LED light 211 depending on the charging status of the power supply unit 40 .

[0252] Furthermore, the pharmaceutical injection device 2 may change the display mode of the LED light 211 depending on the communication connection status between the pharmaceutical injection device 2 and the user's portable device. For example, when the user connects the pharmaceutical injection device 2 to a portable device via Bluetooth (registered trademark), the display mode of the LED light 211 may change depending on the pairing status between the pharmaceutical injection device 2 and the portable device.

[0253] The display mode of the LED light 211 is not limited to the above. Furthermore, the notification means is not limited to the LED light. The notification means may be a notification means that outputs a sound or a notification means that displays text on a display.

[0254] (Operation of Pharmaceutical Injection Device) Next, the operation of the pharmaceutical injection device 2 during self-injection will be described. Figure 12 is a flowchart showing the processing when a user performs self-injection. First, the processing shown in Figure 12 will be described. Then, each step of the processing shown in Figure 12 will be described in detail. The subject of the processing shown in Figure 12 is the user or the pharmaceutical injection device 2.

[0255] 12, the user performs the cartridge mounting process. The cartridge mounting process is a process for mounting the pharmaceutical cartridge 1 in the pharmaceutical injection device 2.

[0256] Next, in step S102 of Figure 12, the pharmaceutical injection device 2 performs a pharmaceutical identification process. The pharmaceutical injection device 2 identifies the pharmaceutical loaded into the syringe 13 of the pharmaceutical cartridge 1 through the pharmaceutical identification process.

[0257] Next, in step S103 of Figure 12, the user performs the cap removal process. By performing the cap removal process, the user removes the cap 11 from the drug cartridge 1 attached to the drug injection device 2. At this time, the needle shield 133 of the drug cartridge 1 is removed from the drug cartridge 1 together with the cap 11.

[0258] Next, in step S104 of FIG. 12, the user carries out a process of bringing the skin detection unit 201 of the pharmaceutical injection device 2 into contact with their own skin (hereafter referred to as the "skin contact process").

[0259] Next, in step S105 of Figure 12, the user performs the injection button pressing process. In the injection button pressing process, the user presses the injection button 202 (see Figure 1) on the pharmaceutical injection device 2.

[0260] Next, in step S106 of Figure 12, the pharmaceutical injection device 2 performs the automatic needle insertion process. During the automatic needle insertion process, the pharmaceutical injection device 2 inserts the needle 131 of the syringe 13 into the user's skin.

[0261] Next, in step S107 of Figure 12, the pharmaceutical injection device 2 performs the automatic injection process. During the automatic needle insertion process, the pharmaceutical injection device 2 injects the pharmaceutical loaded into the syringe 13 into the user.

[0262] Next, in step S108 of Figure 12, the pharmaceutical injection device 2 performs an automatic needle removal process. During the automatic needle removal process, the pharmaceutical injection device 2 removes the needle 131 of the syringe 13 from the user's skin.

[0263] Next, in step S109 of FIG. 12, the user carries out the process of removing the skin detection unit 201 of the pharmaceutical injection device 2 from their own skin.

[0264] Next, in step S110 of Figure 12, the user performs the cartridge removal process. In the cartridge removal process, the user removes the pharmaceutical cartridge 1 from the pharmaceutical injection device 2.

[0265] Finally, in step S111 of FIG. 12, the user ends the self-injection.

[0266] (Cartridge Mounting Process) Next, details of each process shown in Fig. 12 will be described. First, the cartridge mounting process in step S101 in Fig. 12 will be described with reference to Fig. 13.

[0267] In step S201 of FIG. 13, the user inserts the pharmaceutical cartridge 1 into the cartridge storage section 301 of the pharmaceutical injection device 2 (see FIG. 1).

[0268] Figure 10A is a cross-sectional view showing the state in which the drug cartridge 1 is inserted into the drug injection device 2. In the state shown in Figure 10A, the drug injection device 2 has not locked the drug cartridge 1. In other words, the drug injection device 2 has not performed a locking operation. The drug injection device 2 shown in Figure 10A is in its basic state.

[0269] 13, the control unit 204 of the pharmaceutical injection device 2 determines whether or not the pharmaceutical cartridge 1 has been inserted into the pharmaceutical injection device 2. The control unit 204 determines whether or not the pharmaceutical cartridge 1 has been inserted into the pharmaceutical injection device 2 based on the detection value of the cartridge detection unit 206 (see FIG. 2).

[0270] If the cartridge detection unit 206 does not detect the insertion of the medicine cartridge 1 ("NO" in step S202 in FIG. 13), the control unit 204 repeats the process of step S202 in FIG.

[0271] When the cartridge detection unit 206 detects the insertion of the medicine cartridge 1 (YES in step S202 in FIG. 13), the control unit 204 advances the control process to step S203 in FIG.

[0272] Next, in step S203 of FIG. 13, the control unit 204 turns on the main power supply of the pharmaceutical injection device 2.

[0273] Next, in step S204 of Figure 13, the controller 204 determines whether or not the pharmaceutical cartridge 1 is locked to the pharmaceutical injection device 2 based on the detection values ​​of the first detector 207 and the second detector 208. In other words, in step S204 of Figure 13, the controller 204 determines whether or not the pharmaceutical injection device 2 is in a locked state.

[0274] If the pharmaceutical cartridge 1 is not locked to the pharmaceutical injection device 2 ("NO" in step S204 in FIG. 13), the controller 204 repeats the processing of step S204 in FIG.

[0275] If the pharmaceutical cartridge 1 is locked to the pharmaceutical injection device 2 (YES in step S204 in FIG. 13), the controller 204 advances the control process to step S205 in FIG.

[0276] As described above, in step S204 of FIG. 13, the controller 204 determines whether the locking operation of the pharmaceutical injection device 2 has finished.

[0277] Here, we will explain the locking operation of the pharmaceutical injection device 2. Figure 10B is a cross-sectional view showing the state of the pharmaceutical injection device 2 after the locking operation has been completed. When the locking operation is performed, the pharmaceutical injection device 2 transitions from the basic state shown in Figure 10A to the locked state shown in Figure 10B.

[0278] During the locking operation, the pharmaceutical injection device 2 drives the motor 41. The motor 41 is driven in the forward direction. As a result, the motor 41 is driven a predetermined amount in the forward direction. The amount of rotation of the motor 41 during the locking operation may be, for example, an amount of rotation equivalent to a quarter rotation of the feed screw 50 (i.e., 90°).

[0279] The direction in which each element of the actuating unit 5 rotates in response to the rotation of the motor 41 in the forward direction is referred to as a first rotation direction, while the direction in which each element of the actuating unit 5 rotates in response to the rotation of the motor 41 in the reverse direction is referred to as a second rotation direction.

[0280] When the motor 41 rotates, the rotation of the motor 41 is transmitted to the actuation unit 5 (specifically, the feed screw 50) via the speed reducer 42 and the transmission unit 43. As a result, the feed screw 50 rotates a predetermined amount (e.g., 1 / 4 rotation) in a predetermined direction. The rotation direction of the feed screw 50 at this time is the first rotation direction.

[0281] When the feed screw 50 rotates, the torque limiter 52 rotates together with the feed screw 50. At this time, because the rotation of the slider 51 in the first rotation direction is not restricted, the torque acting on the torque limiter 52 is equal to or less than a predetermined value. Therefore, the rotation of the feed screw 50 is transmitted to the slider 51 via the torque limiter 52.

[0282] When the slider 51 rotates in the first rotation direction, the guide groove 510 of the slider 51 is guided by the guide protrusion 310 (see Figure 9) of the case part 3 (specifically, the inner case element 31), and the slider 51 moves forward a predetermined amount.

[0283] At this time, the slider 51 moves a predetermined amount forward from the rear end of the stroke of the slider 51. The amount of forward movement of the slider 51 corresponds to the amount of rotation of the motor 41. The position of the slider 51 after this movement is also referred to as the lock position of the slider 51.

[0284] When the slider 51 moves forward, the latch 53 and the latch cover 54 move forward by a predetermined amount together with the slider 51. Then, the latch cover 54 moves from the position shown in Fig. 10A (also referred to as the basic position) to the position shown in Fig. 10B (also referred to as the locked position).

[0285] 10B, the latch cover 54 externally covers the device-side engaging portion 302 of the holding portion 30 of the case portion 3 (see FIG. 11B). The latch cover 54 maintains the engagement between the device-side engaging portion 302 and the locking engaging portion 103 of the drug cartridge 1. In other words, the latch cover 54 locks the drug cartridge 1 to the drug injection device 2. The drug injection device 2 is then locked.

[0286] The states of the device engaging part 302, locking engaging part 103, and latch cover 54 when the pharmaceutical injection device 2 is in the state shown in FIGS. 10A and 10B will now be described with reference to FIGS. 11A and 11B.

[0287] Fig. 11A is an enlarged cross-sectional view of a portion corresponding to the X1 portion of Fig. 10A cut at a position shifted by a predetermined angle in the circumferential direction. Fig. 11B is an enlarged cross-sectional view of a portion corresponding to the X2 portion of Fig. 10B cut at a position shifted by a predetermined angle in the circumferential direction. Figs. 11A and 11B are cross-sectional views showing the states of the device-side engaging portion 302, the locking engaging portion 103, and the latch cover 54.

[0288] As shown in FIG. 10A, when the drug cartridge 1 is inserted into the drug injection device 2 and the drug cartridge 1 is not locked to the drug injection device 2, the claw portion 302a of the device-side engagement portion 302 is inserted into the locking engagement portion 103 from the radial outside of the drug cartridge 1 (specifically, the case 10), as shown in FIG. 11A.

[0289] 11A, the claw portion 302a has a trapezoidal cross section and has inclined surfaces on the rear end surface and the front end surface.

[0290] The device-side engaging portion 302 elastically deforms to expand in diameter when the case 10 of the medicine cartridge 1 enters the inside of the device-side engaging portion 302 from the front. In the present embodiment, the front end surface of the claw portion 302a is an inclined surface, so that the case 10 can easily enter the inside of the device-side engaging portion 302.

[0291] When the locking engagement portion 103 of the case 10 advances to a position corresponding to the claw portion 302a of the device-side engagement portion 302, the device-side engagement portion 302 elastically deforms to reduce its diameter. As a result, the claw portion 302a engages with the locking engagement portion 103 from the radially outer side. With the claw portion 302a and the locking engagement portion 103 engaged in this manner, the drug cartridge 1 is temporarily fixed to the drug injection device 2.

[0292] Thereafter, as described above, when the latch cover 54 moves forward, the latch cover 54 covers the device-side engaging portion 302 from the outside, as shown in Figure 11B. As a result, the pharmaceutical injection device 2 enters a locked state. In other words, the pharmaceutical cartridge 1 is fixed to the pharmaceutical injection device 2.

[0293] 10B , when the pharmaceutical injection device 2 is in the locked state, the detected portion 541 of the latch cover 54 faces the first detection unit 207. Therefore, the first detection unit 207 detects the detected portion 541 of the latch cover 54. In this state, the first detection unit 207 sends an ON signal to the control unit 204.

[0294] On the other hand, when the pharmaceutical injection device 2 is in the locked state, the detected portion 541 of the latch cover 54 does not face the second detection unit 208. Therefore, the second detection unit 208 does not detect the detected portion 541 of the latch cover 54. In this state, the second detection unit 208 sends an OFF signal to the control unit 204.

[0295] The control unit 204 then detects that the pharmaceutical injection device 2 is in a locked state based on the detection values ​​obtained from the first detection unit 207 and the second detection unit 208.

[0296] As described above, the locking operation of the pharmaceutical injection device 2 is performed by actuating the feed screw 50, slider 51, torque limiter 52, latch 53, and latch cover 54 of the actuation unit 5. The feed screw 50, slider 51, torque limiter 52, latch 53, and latch cover 54 are an example of a locking operation mechanism.

[0297] Returning now to the description of Figure 13. In step S205 of Figure 13, the controller 204 turns on the LED light 211 in a display mode indicating that the pharmaceutical injection device 2 has been started. The controller 204 then ends the cartridge mounting process.

[0298] As described above, when the cartridge mounting process is completed, the pharmaceutical injection device 2 enters the locked state shown in FIG. 10B.

[0299] (Drug Identification Process) Next, the drug identification process of step S102 in Figure 12 will be described. In the drug identification process, the RFID antenna 205 (see Figure 2) of the pharmaceutical injection device 2 reads information about the drug from the RFID tag 101 (see Figure 1) attached to the drug cartridge 1. The RFID antenna 205 then sends the obtained drug information to the control unit 204.

[0300] The information about the drug includes a unique ID, information about the type of drug, information about the lot, and information about the expiration date of the drug. The control unit 204 may send the information about the drug to a mobile terminal wirelessly connected to the drug injection device 2.

[0301] The wireless communication method used to connect the pharmaceutical injection device 2 and the portable terminal may be any of a variety of communication methods, such as Wi-Fi (Wireless Fidelity) (registered trademark) or Bluetooth (registered trademark).

[0302] The portable terminal may notify the user of information related to the pharmaceutical obtained from the pharmaceutical injection device 2. The notification means (for example, the LED light 211) is as described above.

[0303] The information about the drug may include information indicating that the drug cartridge 1 is unused and / or information indicating that the drug cartridge 1 has been used. If the drug cartridge 1 has been used, the control unit 204 may notify the user of this.

[0304] Furthermore, in the drug identification process, if the drug filled into the drug cartridge 1 is not compatible with the drug injection device 2, the control unit 204 may notify the user of this. Furthermore, if the drug filled into the drug cartridge 1 is not compatible with the drug injection device 2, the control unit 204 may unlock the drug cartridge 1 and eject the drug cartridge 1 from the drug injection device 2.

[0305] (Skin Contact Processing) Next, the skin contact processing of step S104 in Figure 12 will be described. During the skin contact processing, the pharmaceutical injection device 2 may present the user with a message prompting them to contact the skin detection unit 201 of the pharmaceutical injection device 2 against the user's skin. Such a message may be presented by the pharmaceutical injection device 2, or may be presented by a mobile terminal wirelessly connected to the pharmaceutical injection device 2.

[0306] Upon receiving the above message, the user places the skin detection unit 201 of the pharmaceutical injection device 2 against the user's skin.

[0307] When skin detection unit 201 detects that the user's skin has come into contact with skin detection unit 201, it sends the detection value to control unit 204. When control unit 204 acquires a detection value from skin detection unit 201, it switches the state of injection button 202 of pharmaceutical injection device 2 to a state where it can accept operational input.

[0308] In other words, the injection button 202 is in a state where it can accept operational input only when the user's skin is in contact with the skin detection unit 201. This configuration helps to prevent malfunctions of the pharmaceutical injection device 2.

[0309] 1, the pharmaceutical injection device 2 has a skin detection unit 201 on one half of its tip surface (specifically, the half on the +Y side). On the other hand, the pharmaceutical injection device 2 has a cartridge storage unit 301 on the other half of its tip surface (specifically, the half on the -Y side).

[0310] Therefore, during the skin contact process, only the skin detection unit 201 comes into contact with the user's skin. The skin detection unit 201 is an example of a first skin contact unit. In other words, in the case of the pharmaceutical injection device 2 shown in Figure 1, only the first skin contact unit provided on one half of the tip of the pharmaceutical injection device 2 comes into contact with the user's skin.

[0311] Figure 16 is a diagram showing a modified example of a pharmaceutical injection device. The pharmaceutical injection device 2A shown in Figure 16 has a skin detection unit 201a (in other words, a first skin-contacting portion) on one half of the tip surface (specifically, the half on the +Y side).

[0312] The pharmaceutical injection device 2A also has a second skin contact section 212 on the other half of the tip surface (specifically, the half on the negative Y-axis side). The pharmaceutical injection device 2A also has a cartridge storage section 301a between the skin detection section 201a and the second skin contact section 212 in the Y-axis direction.

[0313] The rest of the configuration of the pharmaceutical injection device 2A is the same as the configuration of the above-described pharmaceutical injection device 2. Therefore, the second skin-contact section 212 of the pharmaceutical injection device 2A may be provided in the pharmaceutical injection device 2. Furthermore, the description of the pharmaceutical injection device 2A may be interpreted as appropriate by replacing the description of the above-described pharmaceutical injection device 2.

[0314] In pharmaceutical injection device 2A, skin detection unit 201a (in other words, the first skin-contacting portion) and second skin-contacting portion 212 are located on the same plane parallel to the YZ direction. Therefore, in the case of pharmaceutical injection device 2A, during the skin-contacting process, skin detection unit 201a (in other words, the first skin-contacting portion) and second skin-contacting portion 212 come into contact with the user's skin.

[0315] This increases the area of ​​the pharmaceutical injection device 2A that comes into contact with the user's skin. As a result, the state of contact between the pharmaceutical injection device 2A and the user's skin is stabilized. Furthermore, the configuration of the skin detection unit 201a (in other words, the first skin contact portion) and the second skin contact portion 212 makes the user aware that the pharmaceutical injection device 2A is coming into contact with the skin on a surface without tilting it.

[0316] (Injection Button Pressing Process) Next, the injection button pressing process of step S105 in Figure 12 will be described. During the injection button pressing process, the pharmaceutical injection device 2 may notify the user of a message urging them to press the injection button 202 (see Figure 1) on the pharmaceutical injection device 2. Such a message may be notified by the pharmaceutical injection device 2, or by a mobile terminal wirelessly connected to the pharmaceutical injection device 2.

[0317] Upon receiving the above message, the user presses the injection button 202 on the pharmaceutical injection device 2. The control unit 204 terminates the injection button pressing process when it detects that the injection button 202 on the pharmaceutical injection device 2 has been pressed. Once the injection button pressing process is completed, the pharmaceutical injection device 2 is ready to perform the automatic needle insertion process, automatic injection process, and automatic needle removal process described below.

[0318] (Automatic Needle Insertion Processing / Automatic Injection Processing) Next, the automatic needle insertion processing in step S106 and the automatic injection processing in step S107 in FIG. 12 will be described with reference to FIG.

[0319] 14, the pharmaceutical injection device 2 mainly performs the automatic needle insertion process and the automatic injection process. The automatic needle insertion process is performed before the automatic injection process. Once the automatic needle insertion process is completed, the pharmaceutical injection device 2 automatically performs the automatic injection process.

[0320] First, the automatic needle insertion process will be described. The operation of the pharmaceutical injection device 2 in the automatic needle insertion process is the needle insertion operation. Once the injection button press process in step S105 of Figure 12 is completed, the pharmaceutical injection device 2 automatically begins the needle insertion operation.

[0321] 14, the pharmaceutical injection device 2 notifies the user with a message indicating that needle insertion will be performed. This message may be notified by the pharmaceutical injection device 2 itself, or by a mobile terminal wirelessly connected to the pharmaceutical injection device 2.

[0322] In step S302 of Figure 14, the pharmaceutical injection device 2 drives the motor 41. The motor 41 drives in the forward direction. When the motor 41 drives, the power (i.e., rotation) of the motor 41 is transmitted to the actuation unit 5 via the drive unit 4, the speed reducer 42, and the transmission unit 43. The actuation unit 5 then performs the needle insertion operation.

[0323] The direction in which each element of the actuating unit 5 rotates in response to the rotation of the motor 41 in the forward direction is referred to as a first rotation direction, while the direction in which each element of the actuating unit 5 rotates in response to the rotation of the motor 41 in the reverse direction is referred to as a second rotation direction.

[0324] Here, we will explain the needle insertion operation of the pharmaceutical injection device 2. Figure 10B is a cross-sectional view showing the state of the pharmaceutical injection device 2 before the needle insertion operation is performed (i.e., the locked state). Figure 10C is a cross-sectional view showing the state of the pharmaceutical injection device 2 after the needle insertion operation has been performed (i.e., the needle insertion completed state).

[0325] When the needle insertion operation is performed in this manner, the pharmaceutical injection device 2 transitions from the locked state shown in FIG. 10B to the needle insertion complete state shown in FIG. 10C.

[0326] During needle insertion, the pharmaceutical injection device 2 drives the motor 41 in the forward direction. As the motor 41 rotates, the rotation of the motor 41 is transmitted to the actuation unit 5 (specifically, the feed screw 50) via the speed reducer 42 and the transmission unit 43. As a result, the feed screw 50 rotates in a first rotation direction.

[0327] When the feed screw 50 rotates, the torque limiter 52 rotates in the first rotation direction together with the feed screw 50. At this time, because the rotation of the slider 51 in the first rotation direction is not restricted, the torque acting on the torque limiter 52 is equal to or less than a predetermined value.

[0328] Therefore, the rotation of the feed screw 50 is transmitted to the slider 51 via the torque limiter 52. In this state, the torque limiter 52 connects the feed screw 50 and the slider 51 together.

[0329] When the slider 51 rotates, the guide groove 510 of the slider 51 is guided by the guide protrusion 310 (see Figure 9) of the case part 3 (specifically, the inner case element 31), and the slider 51 moves forward by a predetermined amount.

[0330] The slider 51 moves forward until the guide protrusion 310 is positioned at the end point (rear end) of the guide groove 510. At this time, the slider 51 moves from the lock position of the slider 51 to the front end of the stroke.

[0331] At the front end of the stroke, the slider 51 is restricted from rotating by the guide protrusion 310. At the front end of the stroke, the slider 51 is also restricted from moving forward.

[0332] When the slider 51 moves forward, the latch 53 and the latch cover 54 move forward together with the slider 51. Then, the front end of the latch 53 pushes the rear end of the syringe 13 (specifically, the syringe body 130) forward.

[0333] As a result, the entire syringe 13 moves forward. When the entire syringe 13 has moved forward a predetermined amount, the needle 131 of the syringe 13 protrudes forward from the front end of the pharmaceutical injection device 2, as shown in Figure 10C. The needle insertion operation of the pharmaceutical injection device 2 then ends.

[0334] As described above, the needle insertion operation of the pharmaceutical injection device 2 is performed by operating the feed screw 50, slider 51, torque limiter 52, and latch 53 of the operating unit 5. The feed screw 50, slider 51, torque limiter 52, and latch 53 correspond to an example of a needle insertion operation mechanism.

[0335] When the needle insertion operation of the pharmaceutical injection device 2 is completed, the controller 204 carries out the injection operation while driving the motor 41. In other words, the controller 204 continues to drive the motor 41 between the needle insertion operation and the injection operation. In other words, the controller 204 carries out the needle insertion operation and the injection operation continuously. The controller 204 may also stop the motor 41 between the needle insertion operation and the injection operation. In other words, the controller 204 may carry out the needle insertion operation and the injection operation discontinuously.

[0336] 10C , when the pharmaceutical injection device 2 has completed needle insertion, the detected portion 541 of the latch cover 54 faces the second detection unit 208. Therefore, the second detection unit 208 detects the detected portion 541 of the latch cover 54. In this state, the second detection unit 208 sends an ON signal to the control unit 204.

[0337] On the other hand, when the pharmaceutical injection device 2 has completed needle insertion, the detected portion 541 of the latch cover 54 does not face the first detection unit 207. Therefore, the first detection unit 207 does not detect the detected portion 541 of the latch cover 54. In this state, the first detection unit 207 sends an OFF signal to the control unit 204.

[0338] Then, based on the detection values ​​obtained from the first detection unit 207 and the second detection unit 208, the control unit 204 detects that the pharmaceutical injection device 2 has completed the needle insertion operation (i.e., the needle insertion completed state).

[0339] As described above, in the case of this embodiment, it is only after the needle insertion operation of the pharmaceutical injection device 2 is completed that the needle 131 of the syringe 13 protrudes forward from the front end of the pharmaceutical injection device 2. This configuration contributes to improved safety during self-injection.

[0340] Returning to the description of Fig. 14, in step S303 of Fig. 14, the control unit 204 determines whether or not the needle insertion operation is complete. The method of determination is as described above.

[0341] In step S303 of FIG. 14, if it is determined that the needle insertion operation is not completed, the control unit 204 repeats step S303.

[0342] On the other hand, if it is determined in step S303 of FIG. 14 that the needle insertion operation is completed, the control unit 204 advances the control process to step S304.

[0343] 14, the control unit 204 notifies the user with a message indicating that injection will occur. This message may be notified by the pharmaceutical injection device 2, or by a mobile terminal wirelessly connected to the pharmaceutical injection device 2. Once the processing of step S304 in FIG. 14 is complete, the pharmaceutical injection device 2 performs the automatic injection process.

[0344] In step S305 of Figure 14, the pharmaceutical injection device 2 drives the motor 41. At this time, the motor 41 drives in the forward direction. When the motor 41 drives, the power (i.e., rotation) of the motor 41 is transmitted to the actuation unit 5 via the drive unit 4. The actuation unit 5 then performs the injection operation.

[0345] Here, we will explain the injection operation of the pharmaceutical injection device 2. Figure 10C is a cross-sectional view showing the state of the pharmaceutical injection device 2 before the injection operation is performed (i.e., the needle insertion completed state). Figure 10D is a cross-sectional view showing the state of the pharmaceutical injection device 2 after the injection operation is performed (i.e., the injection completed state).

[0346] When the injection operation is performed in this manner, the pharmaceutical injection device 2 transitions from the needle insertion complete state shown in FIG. 10C to the injection complete state shown in FIG. 10D.

[0347] During an injection operation, the pharmaceutical injection device 2 drives the motor 41 in the forward direction. When the motor 41 rotates, the rotation of the motor 41 is transmitted to the actuation unit 5 (specifically, the feed screw 50) via the speed reducer 42 and the transmission unit 43. This causes the feed screw 50 to rotate in a first rotational direction.

[0348] When the feed screw 50 rotates, the rotation of the feed screw 50 is transmitted to the torque limiter 52. In the needle insertion completed state of the pharmaceutical injection device 2 shown in Figure 10C, the slider 51 has moved to the rear end of its stroke.

[0349] In other words, the guide protrusion 310 of the case portion 3 (specifically, the inner case element 31) is located at the end point of the guide groove 510 of the slider 51. In this state, the guide protrusion 310 restricts the rotation of the slider 51 in the first rotation direction.

[0350] Therefore, the torque acting on the torque limiter 52 from the feed screw 50 becomes greater than a predetermined value.

[0351] When the torque acting on the torque limiter 52 exceeds a predetermined value, the torque limiter 52 enters a state where it does not transmit the rotation of the feed screw 50 to the slider 51 (i.e., the torque limiter is in a non-transmission state). In other words, the torque limiter 52 disconnects the feed screw 50 from the slider 51.

[0352] As described above, when the pharmaceutical injection device 2 has completed needle insertion, the slider 51 does not rotate. Therefore, the slider 51 does not move forward. Therefore, the feed screw 50 rotates without moving forward.

[0353] A piston 55 is connected to the front end of the feed screw 50. The piston 55 is threadedly engaged with the feed screw 50 in a state where it is prevented from rotating. Therefore, when the feed screw 50 rotates, the piston 55 moves forward in response to the rotation of the feed screw 50.

[0354] When the pharmaceutical injection device 2 is in the needle insertion completed state, the front end of the piston 55 abuts against the syringe piston 132 of the syringe 13. Therefore, when the piston 55 moves forward, it pushes the syringe piston 132 forward.

[0355] When the syringe piston 132 moves forward, the pharmaceutical agent filled in the syringe 13 is ejected from the tip of the needle 131. The injection operation of the pharmaceutical injection device 2 then ends.

[0356] As described above, the injection operation of the pharmaceutical injection device 2 is carried out by actuation of the feed screw 50 and piston 55 of the actuation unit 5. The feed screw 50 and piston 55 are an example of an injection operation mechanism.

[0357] Returning to the description of Fig. 14, in step S306 of Fig. 14, the control unit 204 determines whether or not the administration of the drug has been completed.

[0358] Specifically, the controller 204 determines whether the piston 55 (in other words, the syringe piston 132) has moved forward a distance sufficient to inject a preset amount of pharmaceutical. In other words, the controller 204 determines whether to terminate the injection operation of the pharmaceutical injection device 2.

[0359] The dosage is set in advance and stored in the memory 210 (see FIG. 2) of the pharmaceutical injection device 2. The memory 210 may store the dosage in association with the type of medicine and the user's identification information.

[0360] 14, the control unit 204 acquires the forward movement amount of the piston 55 (in other words, the position in the front-to-rear direction) based on the detection value of the position detection unit 200 provided in the motor 41. Then, the control unit 204 determines whether or not the administration of the drug is completed based on the acquired forward movement amount of the piston 55.

[0361] 14 , if it is determined that pharmaceutical administration is not complete, the control unit 204 repeats step S306 while continuing the injection operation of the pharmaceutical injection device 2. In this way, the processing of step S306 is always performed during the injection operation of the pharmaceutical injection device 2.

[0362] In step S306 of FIG. 14, if it is determined that the administration of the drug is completed, the control unit 204 advances the control process to S307.

[0363] In step S307 of Figure 14, the control unit 204 stops the motor 41. The injection operation of the pharmaceutical injection device 2 then ends.

[0364] 14 , the control unit 204 notifies the user with a message instructing them to maintain the skin contact state of the skin detection unit 201 of the pharmaceutical injection device 2. This message may be notified by the pharmaceutical injection device 2, or by a mobile terminal wirelessly connected to the pharmaceutical injection device 2.

[0365] 14, the control unit 204 determines whether a predetermined time has elapsed since the end of the processing of step S308. In other words, the control unit 204 determines whether the user has maintained the skin detection unit 201 of the pharmaceutical injection device 2 against their skin for a predetermined time.

[0366] If it is determined in step S309 of FIG. 14 that the predetermined time has not elapsed, the control unit 204 repeats step S309.

[0367] If it is determined in step S309 of FIG. 14 that the predetermined time has elapsed, the control unit 204 ends the control process.

[0368] (Automatic Needle Removal Processing) Next, the automatic needle removal processing of step S108 to step S110 in FIG. 12 will be described with reference to FIG.

[0369] 15, the pharmaceutical injection device 2 mainly performs the automatic needle removal process and the lock release process. The automatic needle removal process is performed after the automatic injection process described above. The pharmaceutical injection device 2 also performs the lock release process during the automatic needle removal process.

[0370] In step S401 in Figure 15, the pharmaceutical injection device 2 begins the automatic needle retraction process. The operation of the pharmaceutical injection device 2 in the automatic needle retraction process is the needle retraction operation. Specifically, in step S401 in Figure 15, the pharmaceutical injection device 2 drives the motor 41. At this time, the motor 41 drives in the reverse direction.

[0371] The rotation direction of the motor 41 during the needle withdrawal operation of the pharmaceutical injection device 2 is opposite to the rotation direction of the motor 41 during the needle insertion operation and injection operation of the pharmaceutical injection device 2.

[0372] In response to the rotation of the motor 41 in the reverse direction, the direction in which each element of the actuation unit 5 rotates is the second rotation direction.

[0373] When the motor 41 is driven, the actuation unit 5 performs the needle withdrawal operation based on the power (i.e., rotation) of the motor 41 .

[0374] Figure 10D is a cross-sectional view showing the state of the pharmaceutical injection device 2 before the needle withdrawal operation is performed (i.e., the injection completion state). Figure 10E is a cross-sectional view showing the state of the pharmaceutical injection device 2 after needle withdrawal is complete (also referred to as the needle withdrawal completion state). Figure 10F is a cross-sectional view showing the state of the pharmaceutical injection device 2 after all needle withdrawal operations have been completed.

[0375] When the needle is removed in this manner, the pharmaceutical injection device 2 transitions from the injection completion state shown in Figure 10D, through the state shown in Figure 10E, to the basic state shown in Figure 10F. In the state shown in Figure 10E, the needle 131 is removed from the user's skin. In other words, needle removal is complete in the state shown in Figure 10E. After the needle 131 is removed from the user's skin, the pharmaceutical injection device 2 transitions from the state shown in Figure 10E to the state shown in Figure 10F.

[0376] As described above, during needle retraction, the pharmaceutical injection device 2 drives the motor 41 in the reverse direction. When the motor 41 rotates, the rotation of the motor 41 is transmitted to the actuation unit 5 (specifically, the feed screw 50) via the speed reducer 42 and the transmission unit 43.

[0377] As a result, the feed screw 50 rotates in the second rotation direction. When the feed screw 50 rotates, the torque limiter 52 rotates together with the feed screw 50.

[0378] At this time, because the rotation of the slider 51 in the second rotation direction is not restricted, the torque acting on the torque limiter 52 is equal to or less than a predetermined value. Therefore, the rotation of the feed screw 50 is transmitted to the slider 51 via the torque limiter 52.

[0379] That is, in this state, the torque limiter 52 connects the feed screw 50 and the slider 51 together.

[0380] When the slider 51 rotates, the guide grooves 510 of the slider 51 are guided by the guide protrusions 310 (see FIG. 9) of the case portion 3 (specifically, the inner case element 31), and the slider 51 moves rearward.

[0381] The slider 51 moves rearward until the guide protrusion 310 is positioned at the start point (front end) of the guide groove 510. At this time, the slider 51 moves from the front end to the rear end of the stroke of the slider 51.

[0382] When the slider 51 moves rearward, the latch 53 and the latch cover 54 move rearward together with the slider 51. The front end of the latch 53 abuts against the rear end of the syringe 13 (specifically, the syringe body 130). Therefore, when the latch 53 moves rearward, the syringe 13 moves rearward due to the biasing force of the spring 12.

[0383] When the latch cover 54 moves rearward, it moves to a position where it does not externally cover the device-side engaging portion 302 of the holding portion 30 of the case portion 3. As a result, the lock of the drug cartridge 1 to the drug injection device 2 is released.

[0384] In this manner, in the case of this embodiment, when the needle withdrawal operation is performed, the lock release operation is also performed automatically during the needle withdrawal operation.

[0385] Furthermore, the feed screw 50 moves rearward as the slider 51 moves rearward. At this time, the feed screw 50 moves rearward while rotating.

[0386] Then, when the slider 51 has moved to the rear end of its stroke, the guide protrusion 310 of the case 3 (specifically, the inner case element 31) is positioned at the start point 511 (i.e., the front end) of the guide groove 510. In this state, the rotation of the slider 51 in the second rotation direction is restricted.

[0387] At this point, the needle 131 of the syringe 13 is withdrawn by the user and stored in the pharmaceutical injection device 2. At this point, the pharmaceutical injection device 2 is in the state shown in Figure 10E. After the pharmaceutical injection device 2 has begun withdrawing the needle, the control unit 204 may determine that the needle withdrawal operation is complete based on the detection values ​​of the first detection unit 207 and the second detection unit 208.

[0388] Specifically, the control unit 204 determines that the needle withdrawal operation is complete when the detection value of the first detection unit 207 is OFF and the detection value of the second detection unit 208 also becomes OFF.

[0389] Returning now to the description of the flowchart in Fig. 15, in step S402 in Fig. 15, the control unit 204 determines whether or not the needle has been removed. The method of determination is as described above.

[0390] 15, if it is determined that the needle removal is not complete, the control unit 204 repeats step S402 and continues the needle removal operation.

[0391] In step S402 of FIG. 15, when it is determined that the needle removal is completed (the state of FIG. 10E), the control unit 204 advances the control process to step S403.

[0392] 15, the control unit 204 notifies the user of a message. Specifically, the control unit 204 notifies the user of a message that the needle removal has been completed.

[0393] The controller 204 also notifies the user with a message informing them that the drug cartridge 1 will be ejected. Such a message may be issued by the drug injection device 2, or by a portable terminal wirelessly connected to the drug injection device 2.

[0394] The control unit 204 then continues the needle retraction operation of the pharmaceutical injection device 2. Below, we return to the explanation of the needle retraction operation of the pharmaceutical injection device 2.

[0395] When the slider 51 moves to the rear end of the stroke and the rotation of the slider 51 in the second rotation direction is restricted, the torque acting on the torque limiter 52 from the feed screw 50 becomes greater than a predetermined value.

[0396] When the torque acting on the torque limiter 52 exceeds a predetermined value, the torque limiter 52 enters a state where it does not transmit the rotation of the feed screw 50 to the slider 51 (i.e., the torque limiter is in a non-transmission state). In other words, the torque limiter 52 disconnects the feed screw 50 from the slider 51.

[0397] In this way, the slider 51 is restricted from rotating in the second rotation direction during the needle retraction operation of the pharmaceutical injection device 2. When the rotation of the slider 51 is restricted, the slider 51 does not move further rearward. As described above, the feed screw 50 moves together with the slider 51.

[0398] Therefore, the rearward movement of the feed screw 50 is restricted during the needle retraction operation of the pharmaceutical injection device 2. When the rearward movement of the feed screw 50 is restricted, the feed screw 50 is in the position shown in Figure 10E.

[0399] Furthermore, with the rearward movement of the feed screw 50 restricted, the feed screw 50 continues to rotate in the second rotation direction based on the power of the motor 41. As a result, the piston 55 connected to the front end of the feed screw 50 moves rearward.

[0400] The piston 55 then moves to the home position shown in Figure 10F. When the piston 55 moves to the home position, the needle retraction operation of the pharmaceutical injection device 2 ends.

[0401] Returning to the description of the flowchart in Fig. 15, in step S404 in Fig. 15, the control unit 204 determines whether the piston 55 has returned to the home position. The control unit 204 determines whether the piston 55 has returned to the home position based on the detection value of the home position detection unit 209. The determination method is as described above.

[0402] 15, if it is determined that the piston 55 has not returned to the home position, the controller 204 repeats step S404, and continues the needle retraction operation of the pharmaceutical injection device 2.

[0403] On the other hand, if it is determined in step S404 of FIG. 15 that the piston 55 has returned to the basic position, the control unit 204 advances the control process to step S405.

[0404] 15, the controller 204 stops the motor 41. The controller 204 then terminates the needle retraction operation of the pharmaceutical injection device 2.

[0405] 15 , the controller 204 notifies the user of a message. Specifically, the controller 204 notifies the user of a message urging them to remove the cartridge. Such a message may be notified by the pharmaceutical injection device 2, or by a portable terminal wirelessly connected to the pharmaceutical injection device 2.

[0406] In step S407 of FIG. 15, the user removes the pharmaceutical cartridge 1 from the pharmaceutical injection device 2.

[0407] 15, the controller 204 determines whether or not the pharmaceutical cartridge 1 has been removed from the pharmaceutical injection device 2. The controller 204 determines whether or not the pharmaceutical cartridge 1 has been removed from the pharmaceutical injection device 2 based on the detection value of the cartridge detector 206.

[0408] If it is determined in step S408 of FIG. 15 that the pharmaceutical cartridge 1 has not been removed from the pharmaceutical injection device 2, the control unit 204 repeats the processing of step S408.

[0409] If it is determined in step S408 of FIG. 15 that the pharmaceutical cartridge 1 has been removed from the pharmaceutical injection device 2, the control unit 204 ends the control process.

[0410] (Operations and Effects of the Present Embodiment) With the drug cartridge 1 and drug injection device 2 of the present embodiment configured as described above, it is possible to provide a drug cartridge and drug injection device that are highly portable.

[0411] First, the drug cartridge 1 of this embodiment is mainly composed of four parts: the case 10, the cap 11, the spring 12, and the syringe 13. This makes it easy to reduce the size of the drug cartridge 1. If a small drug cartridge 1 can be realized, the drug injection device 2 into which the drug cartridge 1 is attached can also be reduced in size.

[0412] In particular, in the case of the medicine cartridge 1 of this embodiment, the spring 12 is directly engaged with the case 10 and the syringe 13 to constantly urge the syringe 13 rearward. This configuration contributes greatly to reducing the number of parts.

[0413] Furthermore, in the case of the pharmaceutical injection device 2 of this embodiment, the locking operation, needle insertion operation, injection operation, needle withdrawal operation, and lock release operation described above are achieved by a single motor 41. This configuration contributes to a significant reduction in the size of the pharmaceutical injection device 2. This configuration also simplifies the structure of the pharmaceutical injection device 2. As a result, the manufacturing costs of the pharmaceutical injection device 2 can be reduced. Other functions and effects obtained from the pharmaceutical cartridge 1 and pharmaceutical injection device 2 of this embodiment are as described above.

[0414] The disclosures of the specification, drawings, and abstract contained in Japanese Patent Application No. 2023-146124, filed on September 8, 2023, are incorporated herein by reference in their entirety.

[0415] The present invention contributes to the realization of a drug cartridge and a drug injection device that are highly portable, and has great industrial applicability.

[0416] REFERENCE SIGNS LIST 1 drug cartridge 10 case 100a, 100b flat portion 101 RFID tag 102a, 102b slit 102c rear end portion 102d front end portion 103 locking engagement portion 104 engagement maintaining portion 105 spring receiving portion 11 cap 110 large diameter cylindrical portion 111 small diameter cylindrical portion 112a, 112b cap side engagement portion 113 diameter expansion allowance space 12 spring 13 syringe 130 syringe body 130a flange portion 131 needle 132 syringe side piston 133 needle shield 2, 2A drug injection device 200 position detection unit 201, 201a skin detection unit (first skin contact portion) 202 injection button 203 main board 204 control unit 205 RFID antenna 206 Cartridge detection portion 207 First detection portion 208 Second detection portion 209 Basic position detection portion 210 Memory 211 LED light 212 Second skin contact portion 3 Case portion 30 Holding portion 301, 301a Cartridge storage portion 302 Device side engagement portion 302a Claw portion 31 Inner case element 310 Guide protrusion portion 4 Drive portion 40 Power supply portion 41 Motor 42 Speed ​​reduction portion 43 Transmission portion 430 First rotation transmission member 431 Second rotation transmission member 5 Actuation portion 50 Feed screw 501 Base portion 502 Screw portion 51 Slider 510 Guide groove 511 Starting point 512 End point 52 Torque limiter 53 Latch 531 Through hole 54 Latch cover 541 Detection target portion 55 Piston 550 Detection target

Claims

1. A drug cartridge used in conjunction with a drug injection device, A syringe for containing the drug, A case for housing the syringe in a manner that allows it to move in the front-to-back direction, A cap attached to the front end of the case, A spring is provided between the syringe and the case, which constantly biases the syringe backward. The aforementioned case is, A first case-side engaging portion that engages with the spring, A second case-side engaging portion that restricts the rearward movement of the syringe, It has a third case-side engaging portion that restricts the forward movement of the syringe, The aforementioned syringe is It has a syringe-side engaging portion that engages with the spring, It is movable in the front-rear direction by the distance between the second case-side engaging portion and the third case-side engaging portion. Medication cartridge.

2. The aforementioned syringe is A syringe body having a needle at its front end, The syringe body has a needle shield attached to its front end, The cap engages with the needle shield, In the process of removing the aforementioned cap, When the cap is pulled forward, the syringe moves forward together with the cap, compressing the spring, and the syringe comes into contact with the third case-side engagement portion. When the cap is pulled further forward, the cap detaches from the case and the needle shield detaches from the syringe body. The drug cartridge according to claim 1.

3. The aforementioned syringe is A syringe body having a needle at its front end, The syringe body has a needle shield attached to its front end, The cap has a cap-side engaging portion that engages with the needle shield, The aforementioned case is, When the syringe is inserted into the case, the expansion-allowing portion allows for the expansion of the diameter of the cap-side engaging portion, The cap has an expansion-preventing portion that prevents the expansion of the cap-side engaging portion when the cap is removed from the case. The drug cartridge according to claim 1.

4. A drug injection device used in which the drug cartridge described in Claim 1 is incorporated, A case section having a storage section for housing the aforementioned drug cartridge, A single motor housed in the aforementioned case, The case portion comprises an operating part, The operating unit operates based on the power of the motor, A needle insertion and removal mechanism that performs needle insertion and removal operations by moving the syringe in the forward and backward direction, An injection mechanism that performs an injection operation by moving the piston of the syringe forward. A locking mechanism that performs a locking operation to lock the aforementioned drug cartridge, and It has a switching mechanism for switching between the needle insertion / removal operation and the injection operation. Drug injection device.

5. The system further includes a cartridge detection unit that detects when the drug cartridge is housed in the storage unit, The operating unit performs the locking operation according to the detection result of the cartridge detection unit. The drug injection device according to claim 4.

6. The case portion has a first locking member that engages with the drug cartridge, The operating part moves in the forward and backward direction by the motor and has a second locking member that prevents the engagement between the drug cartridge and the first locking member from being released in the first position. The drug injection device according to claim 4.

7. The first locking member is cylindrical in shape through which the drug cartridge can be inserted, and constitutes the housing portion. The second locking member is cylindrical in shape so as to be able to cover the outer circumferential surface of the first locking member. The second locking member, in the first position, covers the engagement portion between the drug cartridge and the first locking member from the outside. The drug injection device according to claim 6.

8. The operating unit performs the locking operation by rotating the motor by a first predetermined amount in a predetermined direction when the drug cartridge is housed in the storage unit. The drug injection device according to claim 4.

9. The aforementioned operating part is After the locking operation, the motor is rotated in the predetermined direction to perform the needle insertion operation. After the needle insertion operation, the motor is rotated in the predetermined direction to perform the injection operation. The drug injection device according to claim 8.

10. The operating unit has a first moving member that moves in the forward and backward direction by the motor, The syringe moves forward as the first moving member moves forward during the needle insertion operation. The drug injection device according to claim 4.

11. The first movable member is The outer surface has a spiral guide groove, When rotated by the motor, it moves forward based on the engagement between the guide groove and the guide projection inserted into the guide groove. The drug injection device according to claim 10.

12. The amount of movement of the first moving member in the front-rear direction is the distance in the front-rear direction between the start point and the end point of the guide groove. The drug injection device according to claim 11.

13. The aforementioned operating part is A second moving member is provided on the motor side of the first moving member, and in the injection operation, rotates by the motor to push the drug in the syringe forward, A torque limiter is provided between the first moving member and the second moving member, The torque limiter is In the aforementioned needle insertion operation, the first moving member is connected to the second moving member, In the injection operation, the first moving member is isolated from the second moving member. The drug injection device according to claim 12.

14. The torque limiter separates the first moving member from the second moving member when the first moving member moves to the front end of the stroke. The drug injection device according to claim 13.

15. After the injection operation, the operating unit reverses the motor to move the syringe backward, and then performs a needle removal operation by moving the second moving member backward. The drug injection device according to claim 13.

16. The operating unit performs an operation to unlock the drug cartridge during the needle removal operation. The drug injection device according to claim 15.