Drug solution administration device, intermediate assembly of drug solution administration device, method for assembling drug solution administration device, and medical instrument package

Abstract

An intermediate assembly (Sa) of a drug solution administration device (10) is provided with a first unit (U1) and a second unit (U2) attached to the first unit (U1). The first unit (U1) has a hollow cylindrical housing (12). The second unit (U2) has a drive unit (D) and is attached to a fixing part (27) of the housing (12) of the first unit (U1). In a state in which a syringe (16) is not accommodated inside the first unit (U1), the second unit (U2) is provisionally fixed to the fixing part (27) of the first unit (U1). In a state in which the second unit (U2) is removed from the first unit (U1) and the provisional fixed state is disengaged, and in which the syringe (16) is accommodated inside the housing (12) of the first unit (U1), the second unit (U2) and the first unit (U1) can be formally fixed.

Description

Drug administration device, intermediate assembly of drug administration device, assembly method of drug administration device, and medical device package

[0001] The present invention relates to a medical solution administration device, an intermediate assembly of the medical solution administration device, a method of assembling the medical solution administration device, and a medical device package.

[0002] Japanese Patent Publication No. 6334717 discloses a drug solution administration device that includes a cylindrical casing, a trigger member serving as a needle cover that is slidably attached to the tip of the casing, and a syringe that is housed inside the casing and filled with a drug solution, and that can administer the drug solution in the syringe by operating the trigger member.

[0003] Patent No. 6334717

[0004] In the medical solution administration device, it is desired to simplify the assembly process.

[0005] The present invention aims to solve the above-mentioned problems.

[0006] (1) A first aspect of the present invention is an intermediate assembly of a medicinal liquid administration device comprising a first unit and a second unit attached to the first unit, wherein the first unit has a hollow cylindrical housing, and a syringe filled with medicinal liquid can be accommodated inside the housing, and the second unit has a drive unit that urges a gasket of the syringe toward the tip of the housing, and is attached to a fixing portion provided at the base end of the housing of the first unit, and at least a portion of the second unit is accommodated inside the housing, and the second unit is temporarily fixed to the fixing portion of the first unit when the syringe is not accommodated inside the first unit, and the second unit can be removed from the fixing portion of the first unit to release the temporary fixed state, and the second unit and the first unit can be permanently fixed together when the syringe is accommodated inside the housing of the first unit.

[0007] With this intermediate assembly of a medicinal liquid administration device, compared to a configuration in which the first member, the second member, and the syringe filled with the medicinal liquid are each made into a unit and the three units are finally assembled, by making the first and second units into a temporarily fixed intermediate assembly, it is possible to reduce the number of units to be supplied to the assembly process and simplify the assembly process of the medicinal liquid administration device.

[0008] (2) In the intermediate assembly described in (1) above, the second unit may have a first engaging portion for temporary fixation and a second engaging portion for final fixation, and when the first unit and the second unit are temporarily fixed, the first engaging portion may engage with the fixing portion, and the temporary fixation state between the first unit and the second unit may be released, and when the first unit and the second unit are permanently fixed, the first engaging portion may disengage from the fixing portion, and the second engaging portion may engage with the fixing portion.

[0009] With this configuration, the first unit and the second unit can be temporarily fixed by engaging the first engaging portion with the fixing portion, and the first unit and the second unit can be effectively fixed in place by engaging the second engaging portion with the fixing portion while the syringe is housed.

[0010] (3) In the intermediate assembly described in (2) above, the fixing portion may have a temporary fixing portion and a final fixing portion provided at a position different from the temporary fixing portion, and when the first unit and the second unit are temporarily fixed, the first engaging portion may engage with the temporary fixing portion, and when the first unit and the second unit are finally fixed, the first engaging portion may disengage from the temporary fixing portion and the second engaging portion may engage with the final fixing portion.

[0011] With this configuration, the first unit and the second unit can be temporarily fixed by engaging the first engaging portion with the temporary fixing portion, and the first unit and the second unit can be effectively fixed with the syringe housed in place by engaging the second engaging portion with the final fixing portion.

[0012] (4) In the intermediate assembly described in (3) above, the fixing portion is a hole or recess formed in the housing, and the temporary fixing portion and the actual fixing portion may be formed in different parts of the hole or recess.

[0013] With this configuration, the temporary fixing portion and the final fixing portion can be provided in the same hole or recess, making it easy to form the temporary fixing portion and the final fixing portion.

[0014] (5) In the intermediate assembly described in (3) or (4) above, the permanent fixing portion may be provided closer to the base end than the temporary fixing portion in the axial direction of the housing.

[0015] With this configuration, by moving the second unit in the distal direction, the first engaging portion can be disengaged from the temporary fixing portion in the distal direction, and the second engaging portion can be engaged with the permanent fixing portion.

[0016] (6) In the intermediate assembly described in (5) above, the fixing portion has a first region in which the temporary fixing portion is provided and a second region adjacent to the base end side of the first region in the axial direction of the housing and in which the main fixing portion is provided, and the first region may be formed wider in the circumferential direction of the housing than the second region.

[0017] This configuration makes it possible to easily provide the temporary fixing portion and the permanent fixing portion in one hole or recess.

[0018] (7) In the intermediate assembly described in any one of (2) to (6) above, the fixing portion may be a hole or recess formed in the housing, the first engaging portion may be attached to the base end of the housing and may have a first engaging protrusion provided on the outer surface of a sleeve body housed inside the housing and engageable with the fixing portion, and the second engaging portion may have a second engaging protrusion provided on an end cap attached to the base end of the sleeve body and engageable with the fixing portion.

[0019] With this configuration, the first unit and the second unit can be temporarily fixed by engaging the first engaging protrusion provided on the sleeve body with the fixing portion, and the first unit and the second unit can be effectively fixed permanently by engaging the second engaging protrusion provided on the end cap with the fixing portion.

[0020] (8) In the intermediate assembly described in any one of (2) to (7) above, the fixing portion may be provided in a plurality of portions in the circumferential direction of the housing, and each of the first engaging portion and the second engaging portion may be provided in a plurality of portions in the circumferential direction of the second unit.

[0021] With this configuration, when the second unit is inserted into the first unit and temporarily fixed, it is easy to align the first and second engaging portions with the fixing portion in the circumferential direction of the housing and the second unit.

[0022] (9) In the intermediate assembly described in any one of (3) to (6) above, the housing may have a receiving portion consisting of a hole or recess arranged distally relative to the fixing portion, and when the first unit and the second unit are fixed by the main fixing portion, the first engaging portion may be inserted into the receiving portion.

[0023] With this configuration, when the first unit and the second unit are fixed, the first engaging portion moves from the fixed portion toward the tip and is inserted into the receiving portion, effectively preventing interference between the first engaging portion and the housing.

[0024] (10) A second aspect of the present invention is a drug solution administration device comprising: a first unit having a hollow cylindrical housing; a syringe housed in the housing and filled with a drug solution; and a second unit having a drive unit that urges a gasket of the syringe toward the tip of the housing, the second unit being attached to the first unit and at least a portion of which is housed inside the housing; wherein the base end of the housing of the first unit has a fixing portion, and the second unit has a first engaging portion for temporary fixation and a second engaging portion for final fixation, the first engaging portion is an engaging portion used to temporarily fix the second unit to the fixing portion of the first unit by engaging with the fixing portion before the syringe is housed in the housing of the first unit, and in an assembled state in which the syringe is housed in the housing and the second unit is final fixed to the fixing portion of the first unit, the first engaging portion is disengaged from the fixing portion and the second engaging portion is engaged with the fixing portion.

[0025] With this medicinal liquid administration device, compared to a configuration in which the first member, the second member, and the syringe filled with the medicinal liquid are each made into a unit and the three units are finally assembled, by making the first and second units into a temporarily fixed intermediate assembly, it is possible to reduce the number of units to be supplied to the assembly process and simplify the assembly process of the medicinal liquid administration device.

[0026] (11) A third aspect of the present invention is a method for assembling a drug solution administration device using the intermediate assembly described in (1) above, which may include a first step of removing the second unit from the fixing portion of the first unit of the intermediate assembly and separating it from the first unit in a base end direction; a second step of inserting the syringe from the base end of the first unit into the housing in a tip end direction and accommodating the syringe in the housing; and a third step of inserting the second unit from the base end of the first unit into the housing and finally fixing the second unit to the fixing portion of the first unit.

[0027] According to this method of assembling a medicinal liquid administration device, compared to a configuration in which the first member, the second member, and the syringe filled with the medicinal liquid are each made into a unit and the three units are finally assembled, by making the first and second units into a temporarily fixed intermediate assembly, it is possible to reduce the number of parts supplied to the assembly process and simplify the assembly process of the medicinal liquid administration device.

[0028] (12) In the assembly method described in (11) above, the second unit may have a first engaging portion for temporary fixation and a second engaging portion for permanent fixation, and in the first step, the second unit may be removed from a temporary fixed state in which the first engaging portion is engaged with the fixing portion by disengaging the first engaging portion from the fixing portion, and in the third step, the second engaging portion may be engaged with the fixing portion by which the second unit is permanently fixed relative to the first unit.

[0029] With this method, the first unit and the second unit can be temporarily fixed by engaging the first engaging portion with the fixing portion, and the first unit and the second unit can be effectively fixed in place by engaging the second engaging portion with the fixing portion while the syringe is housed.

[0030] (13) A fourth aspect of the present invention is a medical device package comprising an intermediate assembly of a drug solution administration device described in any one of (1) to (9) above, and a packaging container for accommodating the intermediate assembly.

[0031] With this medical device package, compared to a case where the first unit and the second unit are individually packaged in a packaging container, the intermediate assembly in which the first and second units are temporarily fixed can be packaged together in a packaging container, thereby saving space required for storing the intermediate assembly.

[0032] According to the present invention, the second unit can be temporarily fixed to the fixing portion of the first unit without a syringe housed inside the first unit, the second unit can be detached from the first unit to release the temporary fixation state, and the second unit and the first unit can be permanently fixed together with a syringe housed inside the first unit. Therefore, compared to when the first member, the second member, and the syringe filled with a medicinal solution are each made into a unit (assembly) and three assemblies are provided to the final assembly process, by temporarily fixing the first and second units to one intermediate assembly, it is possible to reduce the number of assemblies to be provided to the final assembly process and simplify the assembly process of the medicinal solution administration device.

[0033] FIG. 1 is an external perspective view of a medicinal liquid administration device according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of first and second units and a syringe of the medicinal liquid administration device shown in FIG. 1. FIG. 3 is an external perspective view of an intermediate assembly composed of the first and second units shown in FIG. 2. FIG. 4 is an exploded perspective view of the medicinal liquid administration device shown in FIG. 1. FIG. 5 is an overall cross-sectional view of the medicinal liquid administration device shown in FIG. 1. FIG. 6 is an enlarged plan view showing the base end of the medicinal liquid administration device. FIG. 7A is a cross-sectional view taken along line VIIA-VIIA in FIG. 6. FIG. 7B is a cross-sectional view taken along line VIIB-VIIB in FIG. 6. FIG. 8 is an enlarged cross-sectional view showing the vicinity of the distal end of the medicinal liquid administration device shown in FIG. 5. FIG. 9 is a partially omitted perspective view of the medicinal liquid administration device shown in FIG. 1. FIG. 10 is an exploded perspective view showing a state in which the drive unit is disassembled from the housing of the first unit. FIG. 11 is an enlarged front view of the vicinity of the coupling mechanism. FIG. 12 is an enlarged cross-sectional view showing a state in which the base end of the holding arm of the cap is tilted radially outward. FIG. 13 is an overall cross-sectional view showing another cross section of the medicinal liquid administration device. FIG. 14 is an exploded perspective view of the drive unit. FIG. 15 is a partially omitted perspective view showing the vicinity of the base end of the sleeve body. FIG. 16 is a cross-sectional view taken along line XVI-XVI in FIG. 6. FIG. 17 is an enlarged plan view showing the base end of the intermediate assembly shown in FIG. 3. FIG. 18 is a partially omitted cross-sectional view of the medicinal solution administration device. FIG. 19 is an enlarged cross-sectional view showing the vicinity of the base end of the medicinal solution administration device of FIG. 13. FIG. 20 is an enlarged perspective view showing the vicinity of the first connection portion of the medicinal solution administration device of FIG. 10. FIG. 21A is a partially cutaway enlarged perspective view showing a state in which the base end of the plunger is inserted into the guide groove of the end guide. FIG. 21B is an explanatory diagram of a first operation in the vicinity of the tip of the plunger. FIG. 22A is a partially cutaway enlarged perspective view showing a state in which the plunger has started to rotate along the inclined guide portion. FIG. 22B is an explanatory diagram of a second operation in the vicinity of the tip of the plunger. FIG. 23 is an exploded perspective view of the intermediate assembly shown in FIG. 3. FIG. 24 is a cross-sectional view taken along line XXIV-XXIV in FIG. 17. Figure 25 is a cross-sectional view taken along line XXV-XXV in Figure 17. Figure 26 is a plan view of a medical device package including an intermediate assembly. Figure 27 is a first explanatory view showing the assembly of the first and second connection portions of the linking mechanism. Figure 28 is a second explanatory view showing the assembly of the first and second connection portions of the linking mechanism.30 is an explanatory diagram showing a state in which the cap is pulled toward the distal end relative to the housing. FIG. 30 is an overall cross-sectional view showing a state in which the cap has been removed from the chemical solution administration device. FIG. 31 is an enlarged cross-sectional view showing the vicinity of the distal end of the chemical solution administration device of FIG. 30. FIG. 32 is an enlarged cross-sectional view showing the vicinity of the base end of the chemical solution administration device of FIG. 30. FIG. 33 is an overall cross-sectional view showing a state in which the chemical solution administration device of FIG. 30 has started to puncture the skin. FIG. 34 is an overall cross-sectional view showing a state in which the chemical solution administration device of FIG. 33 has finished puncturing the skin. FIG. 35 is an enlarged cross-sectional view showing the vicinity of the base end of the chemical solution administration device of FIG. 33. FIG. 36 is an enlarged cross-sectional view showing the vicinity of the base end of the chemical solution administration device of FIG. 34. FIG. 37 is an enlarged cross-sectional view showing the vicinity of the base end of the chemical solution administration device. FIG. 38 is an enlarged cross-sectional view showing the vicinity of the base end of the chemical solution administration device. FIG. 39 is an overall cross-sectional view showing the chemical solution administration device in a state in which chemical solution administration has been completed. FIG. 40 is an overall cross-sectional view showing another cross section of the chemical solution administration device after chemical solution administration has been completed. Fig. 41A is a partially cutaway enlarged perspective view showing a state in which the plunger moves toward the distal end along the linear guide portion. Fig. 41B is a diagram illustrating a third operation near the distal end of the plunger. Fig. 42 is an overall cross-sectional view showing the drug solution administration device in a state in which the puncture needle is housed in the needle cover. Fig. 43 is an enlarged cross-sectional view showing the vicinity of the base end of the drug solution administration device of Fig. 42.

[0034] As shown in Fig. 1, a medicinal solution administration device 10 according to this embodiment is used, for example, to administer a medicinal solution M (see Fig. 5) subcutaneously to a patient who is a user. As shown in Fig. 2, the medicinal solution administration device 10 includes a first unit U1, a second unit U2 attached to the first unit U1, and a syringe 16 housed inside the first unit U1 and filled with the medicinal solution M. In the process of assembling the medicinal solution administration device 10, an intermediate assembly Sa is formed, which is a temporary assembly in which the first unit U1 and the second unit U2 are temporarily fixed together (see Fig. 3).

[0035] As shown in Figure 4, the first unit U1 comprises a hollow cylindrical housing 12, a needle cover 14 that is movably housed inside the housing 12, a cap 18 that is detachably attached to the tip of the housing 12, and a syringe holder 19 that can hold a syringe 16.

[0036] The housing 12 extends axially (in the direction of arrows A and B). The distal end and proximal end of the housing 12 are each open. As shown in FIG. 1 , the peripheral wall of the housing 12 is provided with an observation window 26, a fixing portion 27, and a receiving portion 28. The observation window 26 is formed to penetrate the peripheral wall of the housing 12 and opens at a position corresponding to the position of the outer cylinder 124 of the syringe 16 housed therein. The medicinal solution M in the outer cylinder 124 (see FIG. 2 ) can be confirmed through the observation window 26.

[0037] As shown in FIG. 6 , the fixing portion 27 is provided at the base end of the housing 12. As shown in FIG. 7A , a pair of fixing portions 27 are provided in the circumferential direction of the housing 12. The pair of fixing portions 27 face each other across the central axis of the housing 12. The pair of fixing portions 27 do not have to be positioned facing each other across the central axis of the housing 12. Note that the present invention is not limited to a case where a pair of fixing portions 27 is provided. The number of fixing portions 27 may be one or three or more. The fixing portion 27 is a first hole 27A that penetrates the peripheral wall of the housing 12. As shown in FIG. 6 , the fixing portion 27 has an elongated shape in the circumferential direction relative to the axial direction of the housing 12.

[0038] The fixing portion 27 includes a pair of temporary fixing portions 271 and a permanent fixing portion 272. The first hole 27A of the fixing portion 27 has a first region F1 in which the temporary fixing portion 271 is provided and a second region F2 adjacent to the base end side of the first region F1 and in which the permanent fixing portion 272 is provided. In the circumferential direction of the housing 12, the first region F1 is formed wider than the second region F2. That is, the temporary fixing portion 271 and the permanent fixing portion 272 are provided at different positions in the axial direction of the housing 12, and the permanent fixing portion 272 is disposed closer to the base end (in the direction of arrow A) than the temporary fixing portion 271. The pair of temporary fixing portions 271 are respectively disposed at both ends in the width direction of the first region F1. The two temporary fixing portions 271 protrude evenly circumferentially from both ends in the circumferential direction of the permanent fixing portion 272.

[0039] Note that the present invention is not limited to a case in which the permanent fixing portion 272 is disposed closer to the base end (in the direction of arrow A) than the temporary fixing portion 271. The permanent fixing portion 272 may also be disposed closer to the tip end (in the direction of arrow B) of the temporary fixing portion 271. Furthermore, the present invention is not limited to a case in which the temporary fixing portion 271 and the permanent fixing portion 272 are formed at different positions in one first hole 27A. For example, the temporary fixing portion 271 and the permanent fixing portion 272 may be provided in two holes spaced apart in the axial direction of the housing 12. Furthermore, the fixing portion 27 is not limited to the first hole 27A penetrating the peripheral wall of the housing 12. For example, the fixing portion 27 may be a recess provided in the inner circumferential surface of the peripheral wall of the housing 12 and recessed in the radial direction.

[0040] The receiving portions 28 are provided in pairs spaced apart from each other in the circumferential direction of the housing 12. The pair of receiving portions 28 constitute a receiving portion row 281 (receiving structure). The pair of receiving portions 28 are arranged distally (in the direction of arrow B) relative to the fixed portion 27. The pair of fixed portions 27 and the pair of receiving portions 28 are arranged in a straight line along the axial direction of the housing 12. As shown in FIG. 7B , the receiving portion row 281 is provided in pairs in the circumferential direction of the housing 12. That is, the housing 12 includes two pairs of receiving portion rows 281. The two pairs of receiving portion rows 281 face each other across the central axis of the housing 12. The two pairs of receiving portion rows 281 do not have to be positioned opposite each other across the central axis of the housing 12. Note that the number of receiving portion rows 281 is not limited to two. It is sufficient that the number of receiving portions 28 and the number of fixed portions 27 are the same.

[0041] Each of the pair of receiving portions 28 has a second hole 28A that penetrates the peripheral wall of the housing 12. The pair of second holes 28A and the circumferential end of the first region F1 of the fixing portion 27 are arranged in a straight line in the axial direction of the housing 12. Note that the receiving portions 28 are not limited to the second holes 28A that penetrate the peripheral wall of the housing 12. For example, the receiving portions 28 may be recesses that are provided on the inner peripheral surface of the peripheral wall of the housing 12 and recessed in the radial direction.

[0042] As shown in Figure 8, a pair of recesses 29 are formed at the tip of the housing 12. The recesses 29 have a rectangular cross section and are recessed radially from the inner peripheral surface of the housing 12. The pair of recesses 29 are arranged at positions symmetrical with respect to the axis of the housing 12 on the outer peripheral surface of the housing 12. When the cap 18 is attached to the tip of the housing 12, the recesses 29 are arranged at positions facing the holding arms 148 of the cap 18.

[0043] As shown in Fig. 5, needle cover 14 is movably disposed inside housing 12. As shown in Fig. 4, needle cover 14 includes a cylindrical main body 116, a pair of cover parts 118 extending from main body 116 toward the base end (in the direction of arrow A), and a pair of extension parts 119 extending from the base end of cover part 118.

[0044] The main body 116 is disposed on the tip side (in the direction of arrow B) of the needle cover 14, and a hole 14a penetrating in the axial direction is opened in the center of the main body 116. The cover 118 is disposed symmetrically about the axis of the needle cover 14 and extends along the axial direction.

[0045] The main body 116 has a pair of engagement holes 120. The cover 118 has a syringe guide hole 122 that is long along the axial direction. The syringe guide hole 122 and the engagement hole 120 are arranged linearly along the axial direction of the needle cover 14. The syringe guide hole 122 and the engagement hole 120 are spaced a predetermined distance apart in the axial direction of the needle cover 14.

[0046] The retaining arm 148 of the cap 18 engages with the engagement hole 120. The engagement hole 120 penetrates the main body 116 in the radial direction. The engagement hole 120 has a rectangular shape that is elongated in a direction perpendicular to the axial direction of the needle cover 14. The syringe guide hole 122 penetrates the cover 118 in the radial direction. The syringe holder 19 engages with the syringe guide hole 122 so that it can move axially. The syringe guide hole 122 has a guide function that guides the syringe holder 19 in the axial direction.

[0047] As shown in FIG. 9 , the extension portion 119 extends from the center of the base end of the cover portion 118 further toward the base end. The extension portion 119 extends linearly with a substantially constant width. The base end of the extension portion 119 is provided with the second connection portion 123 of the linking mechanism C. As shown in FIG. 10 , the extension portion 119 is provided with a pair of ribs 119 a. The ribs 119 a are provided on both ends of the extension portion 119 in the width direction and extend along the extension portion 119. The ribs 119 a protrude from the inner surface of the extension portion 119. The base ends 119 b of the ribs 119 a are located near the base end of the extension portion 119.

[0048] The second connecting portion 123 is part of the connecting mechanism C. The second connecting portion 123 is connectable to the first connecting portion 66 of the slide member 64. The connecting mechanism C has first and second connecting portions 66, 123, and is capable of connecting the tip of the slide member 64 and the base end of the needle cover 14.

[0049] As shown in Figure 11, the second connection portion 123 has an extension end 123a that is gradually narrower than the extension portion 119, a convex portion 123b that is located at the base end of the extension end 123a, and a jaw portion 123c that is located at the connection site between the extension end 123a and the convex portion 123b.

[0050] The extending end 123a is inclined so as to gradually narrow in width from the base end of the extending portion 119 toward the base end (direction of arrow A). The sides of the extending end 123a in the width direction are inclined.

[0051] The widthwise side portions of the extending end 123a are substantially parallel to the first and second flexible arm portions 67a, 67b, respectively. That is, the inclination angles of the widthwise side portions of the extending end 123a are substantially the same as the angle θ of the first and second flexible arm portions 67a, 67b, respectively.

[0052] The protrusions 123b protrude on both sides in the width direction perpendicular to the extension direction of the extending end 123a and the extending portion 119. The protrusions 123b are wider than the extending end 123a in the width direction, which is the circumferential direction of the tubular portion 64b. The maximum width dimension of the protrusions 123b is approximately the same as or smaller than the width dimension of the first flexible arm 67a and the second flexible arm 67b at the tip end side. The maximum width dimension of the protrusions 123b is larger than the width dimension of the first flexible arm 67a and the second flexible arm 67b at the base end side. Both ends of the protrusions 123b in the width direction have inclined surfaces 123d. Each inclined surface 123d is inclined toward the center of the protrusions 123b in the width direction in the direction away from the extending end 123a (toward the base end).

[0053] The jaw portion 123c is disposed at the connection between the tip of the protrusion 123b and the base end of the extending end 123a. The jaw portion 123c is recessed inward in the width direction from the width direction end of the protrusion 123b. The second connecting portion 123 is generally T-shaped and is composed of the extending end 123a and the protrusion 123b.

[0054] As shown in Fig. 1, the cap 18 is detachably attached to the tip of the housing 12. As shown in Fig. 8, the cap 18 is cylindrical with a bottom, and has a bottom wall 144 formed at the tip and an annular peripheral wall 146 extending from the bottom wall 144 toward the base end (in the direction of arrow A). The base end of the cap 18 is open. The cap 18 has a pair of holding arms 148 that protrude axially (in the direction of arrow A) from the base end of the peripheral wall 146.

[0055] The holding arms 148 are disposed radially inward relative to the peripheral wall 146 and are capable of tilting radially around the connection points with the peripheral wall 146. The base ends of the holding arms 148 are provided with outer hooks 150 that protrude radially inward. The holding arms 148 are disposed in pairs at symmetrical positions across the axial center of the cap 18.

[0056] When the cap 18 is attached to the tip of the housing 12, the base end of the peripheral wall 146 abuts against the tip of the housing 12, and the pair of retaining arms 148 are inserted into the gap between the housing 12 and the needle cover 14. The pair of retaining arms 148 are positioned to face the recess 29 and the engagement hole 120, and the outer hooks 150 are engaged with the engagement hole 120.

[0057] 12 , the axial length L1 of the engagement hole 120 is greater than the axial length L2 of the outer hook 150 (L1>L2). The outer hook 150 is engaged with the engagement hole 120 in a state where it can move axially (in the directions of arrows A and B).

[0058] 8, when cap 18 is attached to the tip of needle cover 14, recess 29 is positioned so as to be offset distally (in the direction of arrow B) from engagement hole 120. The base end of retaining arm 148 having outer hook 150 is positioned proximally (in the direction of arrow A) from the base end of recess 29.

[0059] 13 , an inner hook 154 that protrudes radially inward is disposed inside the cap 18. The outer cover member 138 of the protective cover 128 is inserted into the inner hook 154. The inner hook 154 engages with the annular groove 140 of the outer cover member 138. This causes the cap 18 to engage with the protective cover 128 via the inner hook 154, and also with the tip of the needle cover 14. With the cap 18 holding the protective cover 128, the cap 18 is attached so as to cover the needle cover 14 and the tip of the housing 12.

[0060] 5, the syringe holder 19 is cylindrical and housed inside the housing 12. The syringe holder 19 has a pair of guide portions 142 that protrude radially outward from the outer circumferential surface. The guide portions 142 are inserted into the syringe guide holes 122 of the needle cover 14. As a result, the syringe holder 19 is held within the needle cover 14 together with the syringe 16 so as to be movable along the axial direction (direction of arrows A and B).

[0061] When the syringe 16 is held in the syringe holder 19 and stored inside the needle cover 14, the puncture needle 126 is positioned at the tip side (in the direction of arrow B), and the outer tube 124 is positioned so that it faces the confirmation window 26 (see Figure 1) opened in the housing 12.

[0062] 3 , the second unit U2 is attached to the fixing portion 27 of the housing 12 of the first unit U1. At least a portion of the second unit U2 is housed inside the housing 12 from the proximal end toward the distal end of the housing 12. The second unit U2 has a drive unit D that urges the gasket 106 of the syringe 16 toward the distal end of the housing 12.

[0063] As shown in FIG. 2, the second unit U2 includes a first engagement portion 301 for temporary fixation to the first unit U1, and a second engagement portion 302 for permanent fixation to the first unit U1.

[0064] As shown in FIG. 14, the drive unit D is configured by assembling a sleeve body 22, an end cap 24, an injection spring 58, a plunger 82, a top member 88, an end guide 68, a sleeve spring 42, a lock pin 44, and a slide member 64.

[0065] An end cap 24 is disposed at the base end of the drive unit D, and an end guide 68 and a top member 88 are disposed at the tip end of the drive unit D (see FIG. 10). The first connection portion 66 of the slide member 64 is disposed adjacent to the end guide 68.

[0066] When administering a medicinal solution using the medicinal solution administration device 10, in the initial state in which the puncture needle 126 is covered by the needle cover 14, the drive unit D has a locking mechanism R (see FIG. 18 ) that prevents the plunger 82 from moving distally due to the injection spring 58. When the needle cover 14 is pressed and moved proximally, the locked state by the locking mechanism R is released, allowing the plunger 82 to move distally.

[0067] The sleeve body 22 is housed on the base end side (direction of arrow A) of the housing 12. The sleeve body 22 is formed to be hollow. The sleeve body 22 has a cylindrical main body 31 and an expanded diameter portion 32 formed on the base end side (direction of arrow A) of the main body 31. The main body 31 is formed with a substantially constant diameter along the axial direction (direction of arrows A and B). The inside of the main body 31 is provided with four guide ribs 34 that protrude radially inward from the inner circumferential surface.

[0068] As shown in Figure 15, the expanded diameter portion 32 is formed in a cylindrical shape. The outer peripheral surface of the expanded diameter portion 32 has a pair of protrusions 321 that protrude radially outward. The pair of protrusions 321 are arranged at positions spaced 180° apart from each other in the circumferential direction of the sleeve body 22. When viewed from the outer peripheral side of the expanded diameter portion 32, each protrusion 321 has a substantially rectangular shape and extends from the base end of the sleeve body 22 toward the tip end. The tip end of each protrusion 321 has a pair of first engagement portions 301.

[0069] The pair of first engaging portions 301 are spaced apart from each other in the circumferential direction of the sleeve body 22. The pair of first engaging portions 301 are provided as a set spaced apart from each other in the circumferential direction of the housing 12. That is, the housing 12 is provided with two pairs of first engaging portions 301. Each of the pair of first engaging portions 301 has a first engaging protrusion 301A that protrudes radially outward from the outer circumferential surface of the protruding portion 321. The first engaging protrusions 301A are spaced apart from each other in the circumferential direction of the sleeve body 22. As shown in FIG. 16 , each first engaging protrusion 301A is formed in a generally trapezoidal shape that tapers in the direction away from the outer circumferential surface of the protruding portion 321. An apex 3011 of the first engaging protrusion 301A is generally parallel to the axial direction of the sleeve body 22. The first engaging protrusion 301A has a distal inclined portion 3012 disposed distally (in the direction of arrow B) relative to the apex 3011, and a proximal inclined portion 3013 disposed proximally (in the direction of arrow A) relative to the apex 3011. The distal inclined portion 3012 inclines from the apex 3011 toward the outer peripheral surface of the protruding portion 321. The proximal inclined portion 3013 inclines from the apex 3011 toward the outer peripheral surface of the protruding portion 321. As shown in FIG. 3 , when the first unit U1 and the second unit U2 are temporarily fixed to form the intermediate assembly Sa, the pair of first engaging portions 301 are respectively engaged with the pair of temporary fixing portions 271 of the fixing portion 27 (see FIG. 17 ). The number of first engaging portions 301 and fixing portions 27 is the same.

[0070] As shown in Figure 5, the guide ribs 34 are spaced apart from one another at 90° intervals along the circumferential direction of the main body 31. The number of guide ribs 34 is not limited to four. At least three guide ribs 34 are provided. The guide ribs 34 protrude linearly from the inner circumferential surface radially inward with a substantially constant thickness. The radial protrusion length of each guide rib 34 is the same. A pair of guide ribs 34 are arranged facing each other across the axial center of the main body 31.

[0071] As shown in Figure 18, a lock pin 44 and a plunger 82, which will be described later, are housed inside the sleeve body 22 so as to be axially movable. As shown in Figure 19, the boundary between the expanded diameter portion 32 and the main body 31 is provided with a plurality of protrusions 38 that protrude radially inward. The protrusions 38 have a rectangular cross section and protrude radially inward from the inner circumferential surface of the main body 31. The base ends of the protrusions 38 form an inclined surface that gradually slopes radially inward.

[0072] A flange 96 of a flexible portion 86 of a plunger 82 (described later) engages with the protrusion 38 on the proximal end side (in the direction of arrow A). The number and arrangement of the protrusions 38 correspond to the number and arrangement of the flexible portions 86.

[0073] The sleeve body 22 is housed inside the housing 12 from the base end of the housing 12, and the expanded diameter portion 32 is engaged with the inner circumferential portion of the housing 12. As a result, the base end of the expanded diameter portion 32 is housed and fixed at a position a predetermined distance from the base end of the housing 12 toward the tip end (in the direction of arrow B).

[0074] 18, the outer peripheral surface of the main body 31 is provided with a pair of locking grooves 40 recessed radially inward. The pair of locking grooves 40 are arranged at positions symmetrical with respect to the axial center of the sleeve body 22, and a locking claw 62 of a locking pin 44, which will be described later, is engaged with the locking grooves 40.

[0075] A sleeve spring 42 is disposed between the outer peripheral surface of the main body 31 and the inner peripheral surface of the housing 12. The sleeve spring 42 is a resilient member formed of a coil spring. The base end of the sleeve spring 42 is engaged with the tip of the expanded diameter portion 32. The tip of the sleeve spring 42 is engaged with a slide member 64, which will be described later. The resilient force of the sleeve spring 42 biases the slide member 64 in a direction that moves it away from the sleeve body 22, i.e., in the tip direction (the direction of arrow B).

[0076] A lock pin 44 is housed inside the sleeve body 22 so as to straddle the expanded diameter portion 32 and the body main body 31. The lock pin 44 is provided so as to be movable in the axial direction (direction of arrows A and B) inside the sleeve body 22. The lock pin 44 has a cylindrical pin main body 46 formed in the center and a pair of arm portions 48 provided on the outer periphery of the pin main body 46. The arm portions 48 are integrally connected to the base end of the pin main body 46.

[0077] The pin body 46 includes a flat end wall portion 50 formed at the base end and perpendicular to the axial direction, a large diameter portion 52 extending from the center of the end wall portion 50 toward the tip side (in the direction of arrow B), and a small diameter portion 54 formed on the tip side (in the direction of arrow B) of the large diameter portion 52 and having a smaller diameter than the large diameter portion 52. The pin body 46 has a hole 56 at its axial center, which extends axially with a constant diameter and linearly penetrates the end wall portion 50, the large diameter portion 52, and the small diameter portion 54. A shaft portion 78 of the end cap 24 and an injection spring 58 (described later) are inserted into the hole 56.

[0078] The base ends of the arms 48 are connected to the end wall 50 of the pin body 46 and are arranged parallel to and spaced a predetermined distance from the outer periphery of the pin body 46. Each arm 48 extends the same length toward its tip (in the direction of arrow B). The tip of each arm 48 has an engagement end 60 that engages with a slide member 64, which will be described later, and a locking claw 62 formed radially inward of the engagement end 60.

[0079] The engagement end 60 is flat and perpendicular to the extension direction of the arm portion 48. The locking claw 62 protrudes radially inward from the engagement end 60 and toward the tip side (in the direction of arrow B). The cross-sectional shape of the locking claw 62 is triangular and tapers toward the tip of the arm portion 48.

[0080] A protrusion 48a protruding outward is provided at the center in the longitudinal direction of the arm portion 48. The protrusion 48a protrudes outward from the outer surface of the arm portion 48 and has a rectangular shape that is elongated in a direction perpendicular to the extension direction of the arm portion 48. The protrusion 48a is inserted into a slit hole 641 of a slide member 64, which will be described later.

[0081] Inside the housing 12, a cylindrical slide member 64 is provided on the tip side (in the direction of arrow B) of the lock pin 44.

[0082] The slide member 64 is disposed inside the housing 12 so as to be movable in the axial direction (directions of arrows A and B). The plunger 82 and the main body 31 of the sleeve body 22 are inserted into the slide member 64.

[0083] As shown in FIG. 14 , the slide member 64 has a cylindrical sleeve body 64a, a tubular portion 64b disposed at the tip of the sleeve body 64a, and a pair of engagement arms 64c extending from the base end of the sleeve body 64a. The tubular portion 64b has a larger diameter than the sleeve body 64a. The boundary between the sleeve body 64a and the tubular portion 64b has a stepped receiving portion 65. As shown in FIG. 9 , the receiving portion 65 holds the tip of the sleeve spring 42 disposed on the outer periphery of the slide member 64. The resilient force of the sleeve spring 42 urges the slide member 64 toward the tip.

[0084] As shown in FIG. 20 , the cylindrical portion 64b of the slide member 64 has a first connecting portion 66. The first connecting portion 66 is part of the coupling mechanism C. A pair of first connecting portions 66 are provided spaced apart from each other along the circumferential direction of the cylindrical portion 64b. The first connecting portions 66 are arranged symmetrically about the axis of the slide member 64. Each first connecting portion 66 has an accommodating recess 66a and first and second flexible arm portions 67a, 67b provided in the accommodating recess 66a. The accommodating recess 66a is a recess recessed radially inward from the outer peripheral surface of the cylindrical portion 64b and opens from the distal end to the proximal end of the cylindrical portion 64b. As shown in FIG. 11 , the accommodating recess 66a has a trapezoidal shape that narrows toward the proximal end of the slide member 64. That is, side walls 661, 662 that define both sides of the accommodating recess 66a in the circumferential direction of the cylindrical portion 64b are inclined inward from the distal end to the proximal end.

[0085] The first and second flexible arms 67a, 67b are spaced apart from each other in the circumferential direction of the tubular portion 64b and are arranged along the inclined side walls 661, 662 of the accommodating recess 66a. The first and second flexible arms 67a, 67b are symmetrical with respect to the center of the accommodating recess 66a. The first and second flexible arms 67a, 67b are spaced apart from and parallel to the side walls 661, 662 of the accommodating recess 66a.

[0086] One end (end on the arrow B direction side) of the first and second flexible arms 67a and 67b is a fixed end 671, 672, which is connected to the tip of the tubular portion 64b. The first and second flexible arms 67a and 67b are inclined at an angle θ with the fixed ends 671, 672 of the first and second flexible arms 67a and 67b as base points. The angle θ is, for example, within a range of 5° to 45°. The other ends (ends on the arrow A direction side) of the first and second flexible arms 67a and 67b, which are free ends 673, 674, are not connected to the tubular portion 64b. The fixed ends 671, 672 of the first and second flexible arms 67a and 67b are positioned closer to the tip of the free ends 673, 674 of the tubular portion 64b.

[0087] The first and second flexible arms 67a, 67b have a cantilever structure that can tilt around fixed ends 671, 672. The first and second flexible arms 67a, 67b are elastically deformable. The length E from the fixed ends 671, 672 to the free ends 673, 674 of the first and second flexible arms 67a, 67b is, for example, 3 mm or more along the extension direction of the first and second flexible arms 67a, 67b. The length of the first flexible arm 67a and the length of the second flexible arm 67b are the same.

[0088] In the accommodating recess 66a, a space is provided between the first flexible arm 67a and the second flexible arm 67b, and the second connecting portion 123 of the needle cover 14, which is part of the connecting mechanism C, is accommodated in the space.

[0089] 14 , the pair of engagement arms 64c of the slide member 64 are disposed symmetrically about the axis of the slide member 64, and each engagement arm 64c protrudes toward the base end of the slide member 64. The engagement arm 64c has a slit hole 641. The slit hole 641 has a rectangular shape along the extension direction of the engagement arm 64c. The base end of the slit hole 641 has a protruding piece 642 that protrudes from the base end of the engagement arm 64c toward the tip. The protruding piece 642 is inclined inward toward the tip.

[0090] 18 , a portion of the arm portion 48 of the lock pin 44 is inserted into the slit hole 641. The engagement end 60 of the lock pin 44 can engage with the tip of the slit hole 641. The protruding portion 48a of the arm portion 48 can engage with the protruding piece 642. This engages the lock pin 44 with the slide member 64, preventing the lock pin 44 from coming off the slide member 64 in the proximal direction.

[0091] As shown in Fig. 9, the end guide 68 is disposed so as to face the tip of the slide member 64. The end guide 68 is cylindrical and has approximately the same diameter as the slide member 64. As shown in Fig. 18, a plunger 82 is inserted into the end guide 68 so as to be axially movable.

[0092] 21A , the inner circumferential surface of the end guide 68 is provided with a guide groove 70 for rotating the plunger 82. The guide groove 70 is recessed radially outward relative to the inner circumferential surface of the end guide 68. A flange 96 of a flexible portion 86 of the plunger 82 (described later) is inserted into the guide groove 70. The guide grooves 70 are arranged at four locations circumferentially spaced at equal intervals in accordance with the number and arrangement of the flexible portions 86.

[0093] 22A , each guide groove 70 includes an inclined guide portion 72 and a linear guide portion 74. The inclined guide portion 72 is inclined toward the tip (direction of arrow B) with respect to the axial direction (direction of arrows A and B) of the end guide 68. The linear guide portion 74 extends in a straight line from the tip of the inclined guide portion 72. The width dimension along the circumferential direction of the linear guide portion 74 is approximately equal to or slightly larger than the width dimension of a flange portion 96 of the plunger 82, which will be described later.

[0094] 18 , the end cap 24 has a lid portion 76 that closes the base end of the housing 12, and a shaft portion 78 that extends from the center of the lid portion 76 toward the tip side (in the direction of arrow B). The lid portion 76 is disk-shaped and has the same diameter as the outer diameter of the housing 12.

[0095] The lid portion 76 has a retaining portion 80 protruding from the end face on the tip side, and a pair of connecting pieces 81 protruding from the tip of the retaining portion 80. The retaining portion 80 is formed in an annular shape protruding from the end face of the lid portion 76. The retaining portion 80 abuts against the base end of the expanded diameter portion 32 of the sleeve body 22, thereby restricting and holding the sleeve body 22 housed inside the housing 12 from moving in the base end direction (direction of arrow A).

[0096] As shown in FIG. 4 , the retaining portion 80 has a pair of second engaging portions 302. The pair of second engaging portions 302 are spaced apart in the circumferential direction of the end cap 24. Each of the pair of second engaging portions 302 has a second engaging protrusion 302A that protrudes radially outward from the outer circumferential surface of the retaining portion 80. The second engaging portion 302 includes a locking portion 3021 provided at the base end and an inclined portion 3022 extending from the locking portion 3021 toward the tip end. The locking portion 3021 is substantially perpendicular to the axial direction of the end cap 24. The inclined portion 3022 inclines radially inward from the radial outer end of the locking portion 3021 toward the tip end (direction of arrow B). As shown in FIG. 1 , when the first unit U1 and the second unit U2 are finally fixed to each other, the second engaging portion 302 engages with the final fixing portion 272 of the fixing portion 27 (see FIG. 16 ). 6 , the second engaging protrusion 302A engages with the main fixing portion 272 of the first hole 27A in the housing 12. Specifically, the locking portion 3021 engages with the base end side of the main fixing portion 272, thereby preventing the end cap 24 from moving in the base end direction (direction of arrow A) relative to the housing 12. By fixing the end cap 24 to the housing 12, the end cap 24 is positioned axially and circumferentially relative to the housing 12.

[0097] Note that the present invention is not limited to a case in which the first engaging portion 301 is provided on the sleeve body 22 and the second engaging portion 302 is provided on the end cap 24. The first engaging portion 301 may be provided on the end cap 24 and the second engaging portion 302 may be provided on the sleeve body 22.

[0098] As shown in Figure 5, the shaft portion 78 is a shaft body that extends axially toward the tip side (in the direction of arrow B). The shaft portion 78 is housed inside the housing 12 and the sleeve body 22, and extends to near the axial center of the housing 12. The injection spring 58 and plunger 82 are inserted around the outer periphery of the shaft portion 78. The injection spring 58 is a coil spring and is formed long enough to correspond to the axial length of the shaft portion 78. The injection spring 58 is interposed between the plunger 82 (described later) and the end face of the cover portion 76, and the resilient force of the injection spring 58 urges the plunger 82 toward the tip side (in the direction of arrow B).

[0099] When the end cap 24 is attached to the base end of the housing 12 , the open base end is closed by the lid portion 76 , and the shaft portion 78 is positioned on the axis of the housing 12 .

[0100] 18, the plunger 82 has a cylindrical shape that is long in the axial direction (the direction of arrows A and B). The plunger 82 includes a rod main body 84 formed with a constant diameter along the axial direction, a plurality of flexible portions 86 formed on the base end side (the direction of arrow A) of the rod main body 84 and divided in the circumferential direction, and an attachment portion 90 formed on the tip side (the direction of arrow B) of the rod main body 84 and to which a top member 88 (described later) is attached.

[0101] The rod main body 84 is formed with a circular cross section. As shown in FIG. 4 , four slide grooves 92 recessed radially inward are formed on the outer peripheral surface of the rod main body 84. The slide grooves 92 are recessed with a rectangular cross section relative to the outer peripheral surface of the rod main body 84. As shown in FIG. 18 , a guide rib 34 of the sleeve body 22 is inserted into each slide groove 92. The slide grooves 92 are spaced at equal intervals in the circumferential direction corresponding to the number and arrangement of the guide ribs 34. There are four slide grooves 92, corresponding to the guide ribs 34.

[0102] When the plunger 82 is housed inside the sleeve body 22 , the tip of each guide rib 34 is inserted into each slide groove 92 .

[0103] The rod body 84 has a first rod hole 94 extending along the axial direction (direction of arrows A and B) inside, and the shaft portion 78 of the end cap 24 and the injection spring 58 are inserted into the first rod hole 94.

[0104] The flexible portions 86 protrude in the axial direction (in the direction of arrow A) from the base end of the rod main body 84 and are arranged so as to be spaced apart from each other in the circumferential direction. The flexible portions 86 are arranged between two adjacent slide grooves 92. The base end side (in the direction of arrow A) of the flexible portions 86 can tilt radially, with the tip side (in the direction of arrow B) of the flexible portions 86 connected to the rod main body 84 serving as a fulcrum. As shown in FIG. 19 , the base end of the flexible portions 86 is provided with a flange portion 96 that protrudes radially outward. The surface of the flange portion 96 on the tip side (in the direction of arrow B) is an inclined surface that gradually slopes radially outward toward the base end side.

[0105] The flexible portion 86 expands radially outward relative to the rod main body 84. The small diameter portion 54 of the lock pin 44 is inserted into the flexible portion 86. The inner diameter of the flexible portion 86 is larger than the inner diameter of the first rod hole 94.

[0106] The outer diameter D1 of the flange portion 96 of the flexible portion 86 is slightly larger than the inner diameter D2 of the main body 31 of the sleeve body 22 (D1>D2).

[0107] 14 , the mounting portion 90 has a smaller diameter than the rod main body 84. The outer peripheral surface of the mounting portion 90 is provided with a pair of engagement pieces 98 that protrude radially outward. The pair of engagement pieces 98 are engaged with a top member 88, which will be described later. The engagement pieces 98 extend in a horizontal direction perpendicular to the axial direction of the plunger 82 and are positioned symmetrically with respect to the axial center of the plunger 82.

[0108] 18 , the mounting portion 90 has a second rod hole 100 extending axially (in the direction of arrows A and B) inside. The second rod hole 100 has a smaller diameter than the first rod hole 94, and the shaft portion 78 of the end cap 24 is inserted through the second rod hole 100. The tip of the injection spring 58 engages with a step formed at the boundary between the second rod hole 100 and the first rod hole 94. As a result, the elastic force of the injection spring 58 urges the plunger 82 in a direction that moves it away from the end cap 24, i.e., toward the tip (in the direction of arrow B).

[0109] The top member 88 is cup-shaped and open on the base end side (in the direction of arrow A). The top member 88 is rotatable relative to the attachment portion 90 of the plunger 82. The top member 88 includes a cylindrical cup portion 102 disposed on the base end side, and an attachment portion 104 protruding from the tip of the cup portion 102. A gasket 106 made of an elastic material is attached to the top member 88 so as to cover the outer periphery of the attachment portion 104.

[0110] The mounting portion 90 of the plunger 82 is inserted from the base end side into the cup portion 102. As shown in Fig. 21B, a pair of guide grooves 108 are formed on the outer circumferential surface of the cup portion 102, penetrating radially and into which the engaging pieces 98 of the plunger 82 are inserted.

[0111] The guide grooves 108 are arranged in pairs symmetrically about the axial center of the cup portion 102. The guide grooves 108 have a horizontal portion 110 formed near the base end of the cup portion 102 and extending circumferentially, and a vertical portion 112 extending from one circumferential end to the tip end (in the direction of arrow B) perpendicular to the horizontal portion 110. The guide groove 108 is generally L-shaped and made up of the horizontal portion 110 and the vertical portion 112. The connection portion between the horizontal portion 110 and the vertical portion 112 has an inclined portion 114 inclined at a predetermined angle.

[0112] The top member 88 has the mounting portion 90 of the plunger 82 inserted into the cup portion 102, and the engagement pieces 98 inserted into the pair of guide grooves 108. This connects the top member 88 and the plunger 82 in the axial direction, allowing them to move together in the axial direction. After the gasket 106 is attached to the mounting portion 104 of the top member 88, the top member 88 is inserted into the outer cylinder 124 of the syringe 16, which will be described later.

[0113] As shown in Fig. 5, the syringe 16 is housed inside the needle cover 14 inside the first unit U1. The syringe 16 includes a hollow outer cylinder 124, a gasket 106 slidably inserted inside the outer cylinder 124, a puncture needle 126 provided at the tip of the outer cylinder 124 and protruding in the tip direction (in the direction of arrow B), and a protective cover 128 attached to the tip of the outer cylinder 124. As shown in Fig. 2, the syringe 16 is a unit in which the outer cylinder 124, the gasket 106 (see Fig. 4), the puncture needle 126, and the protective cover 128 are integrally assembled.

[0114] 5, a cylindrical syringe holder 19 is disposed on the outer periphery of the outer cylinder 124, and the outer cylinder 124 is held by the syringe holder 19. The medicinal liquid M used may be, for example, a liquid used for subcutaneous injection into a patient.

[0115] The outer cylinder 124 is a hollow body formed in a substantially cylindrical shape with an opening at its base end. The interior of the outer cylinder 124 is filled with a medicinal solution M. The outer periphery of the base end of the outer cylinder 124 is provided with a flange 132 that protrudes radially outward. The tip of the outer cylinder 124 is provided with a needle holding portion 134. The needle holding portion 134 has a reduced diameter relative to the outer cylinder 124 and protrudes toward the tip. The needle holding portion 134 holds the base end of the puncture needle 126.

[0116] The outer cylinder 124 is formed from a transparent resin material, and the remaining amount of the medicinal liquid M filled inside can be seen from the outside through the confirmation window 26 in the housing 12. A flange 132 of the outer cylinder 124 is engaged with the base end of the syringe holder 19. This prevents the syringe 16 from moving axially relative to the syringe holder 19, and the syringe holder 19 covers the outer periphery of the syringe 16 and holds it integrally.

[0117] The gasket 106 is made of an elastic material such as rubber. The gasket 106 is attached to the mounting portion 104 of the top member 88, and is inserted into the interior of the outer tube 124 through the proximal end opening of the outer tube 124. The gasket 106 is housed in the outer tube 124 so as to be slidable in the axial direction along the inner circumferential surface of the outer tube 124. By inserting the gasket 106 into the interior of the outer tube 124, the proximal end side of the outer tube 124 is liquid-tightly sealed, and the medicinal solution M is enclosed inside the outer tube 124.

[0118] The puncture needle 126 is a hollow body having a flow path therein through which the medicinal liquid M flows. The puncture needle 126 protrudes from the needle holding portion 134 toward the tip. The flow path of the puncture needle 126 communicates with the interior of the outer tube 124, which is filled with the medicinal liquid M. The medicinal liquid M filled inside the outer tube 124 is discharged from the tip of the puncture needle 126 and administered to the patient.

[0119] The protective cover 128 is attached to the tip of the outer tube 124 and covers the puncture needle 126. The protective cover 128 comprises a needle shield 136 made of an elastic material such as rubber and attached to the needle holding portion 134, and an outer cover member 138 that covers the outer periphery of the needle shield 136. The base end of the needle shield 136 is attached to the needle holding portion 134 so as to cover the puncture needle 126. The outer cover member 138 is fitted so as to make sliding contact with the outer periphery of the needle shield 136. As shown in Figure 13, an annular groove 140 recessed radially inward is formed in the outer periphery of the outer cover member 138. An inner hook 154 of the cap 18, which will be described later, engages with the annular groove 140.

[0120] Next, a description will be given of the case where an intermediate assembly Sa in which the second unit U2 is temporarily fixed to the first unit U1 is assembled without accommodating the syringe 16. The intermediate assembly Sa is assembled prior to final assembly of the first and second units U1 and U2, which require substantially the same manufacturing environment, because the manufacturing environment of the syringe 16, into which the medicinal solution M is filled, requires a higher level of cleanliness than the manufacturing environment of the first and second units U1 and U2.

[0121] The intermediate assembly Sa is assembled as follows.

[0122] From the state shown in FIG. 23 , the distal end of the second unit U2 is inserted into the proximal end of the housing 12 of the first unit U1, and then the second unit U2 is moved distally (in the direction of arrow B) relative to the first unit U1. The first engaging portion 301 of the second unit U2 is inserted into the housing 12. At this time, the distal inclined portion 3012 of the first engaging portion 301 contacts the proximal end of the housing 12, thereby pushing the inner circumferential surface of the housing 12 radially outward, and the first engaging protrusions 301A move distally. As shown in FIG. 24 , the pair of first engaging protrusions 301A are inserted into and engaged with the pair of temporary fastening portions 271 of the fastening portion 27 of the first unit U1 (see FIG. 17 ). This results in a temporary fastening state in which relative axial and circumferential movement between the first unit U1 and the second unit U2 is restricted. An intermediate assembly Sa is completed in which the first unit U1 and the second unit U2 are temporarily fastened.

[0123] 3, the intermediate assembly Sa is in a provisionally assembled state in which the syringe 16 is not housed in the first unit U1 and a portion of the second unit U2 is housed inside the first unit U1, with a portion of the second unit U2 protruding in the proximal direction (the direction of arrow A) from the proximal end of the housing 12. Specifically, the lid portion 76 of the end cap 24 is spaced from the proximal end of the housing 12 in the proximal direction (the direction of arrow A), with a portion of the pressing portion 80 exposed to the outside. At this time, as shown in FIG. 25, the second engaging portion 302 is disposed in the proximal direction relative to the main fixing portion 272 of the fixing portion 27, and the main fixing portion 272 and the second engaging portion 302 are in a disengaged state.

[0124] Before the medicinal solution administration device 10 including the syringe 16 is assembled, the intermediate assembly Sa is housed in a packaging container 156 and stored as a medical device package P, as shown in Fig. 26 . The medical device package P includes the intermediate assembly Sa of the medicinal solution administration device 10 and a packaging container 156 that houses the intermediate assembly Sa. The packaging container 156 includes a container body 160 having a storage portion 158. The container body 160 is formed in a rectangular shape in a plan view.

[0125] The container body 160 includes a storage section 158 and an open end 162. The open end 162 is located at the upper end of the container body 160. The interior of the container body 160 is open through the open end 162. Note that the container body 160 is not limited to being open. For example, the interior of the container body 160 may be sealed by providing a sealing film or the like on the open end 162 of the container body 160.

[0126] The storage section 158 is recessed downward from the open end 162. A plurality of storage sections 158 are provided in the container body 160, and are arranged in parallel in the longitudinal direction of the container body 160. Note that the number of storage sections 158 is not limited to a plurality. The container body 160 may be provided with a single storage section 158.

[0127] An intermediate assembly Sa is accommodated in each accommodation section 158. The depth of each accommodation section 158 relative to the opening end 162 is constant, and the intermediate assembly Sa is held substantially horizontally in each accommodation section 158. The accommodation section 158 is open on the side of the opening end 162. The longitudinal dimension of each accommodation section 158 is equal to or greater than the longitudinal dimension of the intermediate assembly Sa.

[0128] Next, the case where the intermediate assembly body Sa is used to assemble the drug solution administration device 10 (final assembly process) will be described.

[0129] 23 , in the first step, the second unit U2 is pulled proximally from the first unit U1 of the intermediate assembly Sa, thereby disengaging the first engagement protrusions 301A (first engagement portions 301) proximally (in the direction of arrow A) from the temporary fixing portions 271 of the fixing portion 27. This releases the temporary fixed state between the first unit U1 and the second unit U2. At this time, the proximal inclined portions 3013 of the first engagement protrusions 301A come into contact with the proximal ends of the temporary fixing portions 271, thereby pushing the inner circumferential surface of the housing 12 radially outward, and the first engagement protrusions 301A can move proximally while in contact with the inner circumferential surface of the housing 12 (see the two-dot chain line in FIG. 16 ).

[0130] In the first step, the distal end of the second unit U2 is removed in the proximal direction (direction of arrow A) relative to the proximal end of the first unit U1. Then, in the second step, from the state shown in Fig. 2, the syringe 16 is inserted from the proximal end of the first unit U1 toward the distal end into the housing 12. At this time, the syringe 16 is inserted into the housing 12 from the protective cover 128 side. The syringe 16 is held by a syringe holder 19 housed inside the housing 12 (see Fig. 5).

[0131] Next, in the third step, the second unit U2 is inserted into the housing 12 from the base end of the first unit U1 and pushed distally beyond the temporary fixing position. As a result, as shown in FIG. 16 , the first engaging portion 301 of the second unit U2 moves distally past the fixing portion 27 (temporary fixing portion 271) and is inserted into the receiving portion 28 (second hole 28A). At the same time, the second engaging portion 302 is inserted into the permanent fixing portion 272 of the fixing portion 27 while the inclined portion 3022 slides against the inner circumferential surface of the housing 12. At this time, the inclined portion 3022 facilitates insertion of the second engaging portion 302 into the housing 12. The locking portion 3021 of the second engaging portion 302 is locked by engaging with the base end of the permanent fixing portion 272. Inserting the first engaging portion 301 into the receiving portion 28 prevents contact between the first engaging portion 301 and the housing 12.

[0132] In the second unit U2, the base end of the drive unit D moves toward the base end of the needle cover 14, and the first connecting portion 66 and the second connecting portion 123 face each other in the axial direction (the direction of arrows A and B) as shown in Fig. 27. As shown in Fig. 28, when the drive unit D is further moved toward the tip (the direction of arrow B), the convex portion 123b of the second connecting portion 123 is inserted from the tip of the tubular portion 64b into the accommodating recess 66a of the first connecting portion 66. In the accommodating recess 66a, the convex portion 123b is inserted between the first flexible arm 67a and the second flexible arm 67b.

[0133] When the inclined surface 123d of the protrusion 123b comes into contact with the first flexible arm 67a and the second flexible arm 67b, the first flexible arm 67a and the second flexible arm 67b are pressed in directions away from each other along the circumferential direction of the tube portion 64b, causing the first and second flexible arms 67a, 67b to tilt away from each other with the fixed ends 671, 672 as fulcrums.

[0134] The protrusions 123b and the extending ends 123a are inserted into the receiving recesses 66a while the first and second flexible arms 67a, 67b are pushed apart in the circumferential direction of the cylindrical portion 64b. As shown in Fig. 11 , when the protrusions 123b pass over the free ends 673, 674 of the first and second flexible arms 67a, 67b, the first and second flexible arms 67a, 67b are tilted toward each other by their respective resilient forces (shown by the two-dot chain lines in Fig. 28 ). As a result, the protrusions 123b of the second connecting portion 123 engage with the base ends of the first and second flexible arms 67a, 67b, and the free ends 673, 674 of the first and second flexible arms 67a, 67b engage with the jaws 123c of the protrusions 123b. The first connecting portion 66 of the slide member 64 and the second connecting portion 123 of the needle cover 14 are connected in the axial direction (direction of arrows A and B) by the convex portion 123b, the first flexible arm portion 67a, and the second flexible arm portion 67b.

[0135] 1, the second unit U2 is fixed to the fixing portion 27 of the first unit U1 in a state in which the relative axial movement and the relative circumferential movement between the first unit U1 and the second unit U2 are restricted. With the syringe 16 housed inside the first unit U1, the chemical solution administration device 10 is in a fully assembled state in which the first unit U1 and the second unit U2 are fully fixed. In the fully assembled state, the lid portion 76 of the end cap 24 of the chemical solution administration device 10 abuts against the base end of the housing 12, closing the base end.

[0136] In the assembled state of the drug solution administration device 10, the first engaging portion 301 is disengaged from the fixing portion 27 (temporary fixing portion 271), and the second engaging portion 302 is engaged with the fixing portion 27 (full fixing portion 272). In other words, the first engaging portion 301 is an engaging portion that is used to temporarily fix the second unit U2 to the fixing portion 27 of the first unit U1 by engaging with the fixing portion 27 before the syringe 16 is housed in the housing 12 of the first unit U1.

[0137] Next, administration of the medicinal liquid M by the medicinal liquid administration device 10 will be described.

[0138] In the drug solution administration device 10 before use shown in Figure 5, the cap 18 is removed from the housing 12 and the tip of the needle cover 14. At this time, the patient grasps the cap 18 on the housing 12 and pulls it in a direction (indicated by arrow B) that moves the cap 18 away from the housing 12. As a result, as shown in Figure 29, the cap 18 moves away from the tip of the needle cover 14, and the outer hook 150 moves toward the tip (indicated by arrow B) within the engagement hole 120.

[0139] As the outer hook 150 moves distally, it comes to a position facing the recess 29. The cap 18 is further pulled distally (in the direction of arrow B). As a result, as shown in FIG. 12 , the outer hook 150 comes into contact with the distal end of the engagement hole 120, causing the retaining arm 148 to tilt radially outward. As the base end of the retaining arm 148 with the outer hook 150 moves into the recess 29, the retaining arm 148 (outer hook 150) disengages from the engagement hole 120. The retaining arm 148, including the outer hook 150, then moves distally through the recess 29 and the gap between the housing 12 and the needle cover 14.

[0140] As the cap 18 moves toward the tip, the protective cover 128 held by the inner hook 154 moves together with the cap 18. This causes the protective cover 128 to detach from the needle holding portion 134 of the outer cylinder 124.

[0141] The engagement of the cap 18 with the needle cover 14 by the holding arm 148 is released, and the cap 18 is completely removed from the tip of the needle cover 14. As a result, as shown in Figure 30, the housing 12 and the tip of the needle cover 14 are opened, and the protective cover 128 that had been covering the puncture needle 126 is simultaneously removed.

[0142] Next, the medicinal liquid M is administered using the medicinal liquid administration device 10 with the cap 18 removed.

[0143] In the state before puncturing of the medicinal solution administration device 10, the relationship between the plunger 82 and the lock pin 44 is as shown in Figure 18. Because the lock pin 44 is inserted inside the flexible portion 86 of the plunger 82, the lock pin 44 restricts the inward tilting of the flexible portion 86. In other words, the flexible portion 86 cannot tilt inward. Because the flange 96 of the flexible portion 86 is engaged with the protrusion 38 of the sleeve body 22, the plunger 82 cannot move toward the distal end.

[0144] As shown in Figure 30, the patient grasps the housing 12 of the medical solution administration device 10 and presses the tip of the needle cover 14 protruding from the tip of the housing 12 against the skin S, which will be the desired puncture site, at approximately a right angle. At this time, the distal and proximal ends of the medical solution administration device 10 are in the states shown in Figures 31 and 32, respectively. Next, as shown in Figure 33, the housing 12 is continuously pushed further toward the skin S (tip side, direction of arrow B). As the housing 12 is pushed toward the skin S, the needle cover 14 is pushed by the skin S and moves relative to the housing 12 in the proximal direction against the elastic force of the sleeve spring 42. Figure 33 shows the state in which the needle tip of the puncture needle 126 has just begun to contact the skin S.

[0145] 34 , as the housing 12 is further pressed toward the skin S, the puncture needle 126 of the syringe 16 protrudes from the hole 14a of the needle cover 14 toward the tip side (in the direction of arrow B). This causes the puncture needle 126 to puncture the skin S and enter a puncture-completed state in which it has been inserted to a predetermined depth. In the puncture-completed state, the tip of the housing 12 is in approximately the same position as the tip of the needle cover 14.

[0146] 30 to 34 , as the needle cover 14 moves proximally relative to the housing 12, the slide member 64 also moves proximally relative to the housing 12. As shown in FIGS. 35 and 36 , as the slide member 64 moves proximally, the tip of the slit hole 641 of the slide member 64 pushes the engagement end 60 provided at the tip of the arm portion 48 of the lock pin 44 proximally, so that the lock pin 44 also moves proximally relative to the housing 12.

[0147] 37 , as the lock pin 44 moves relative to the housing 12 toward the proximal end (direction of arrow A), the small diameter portion 54 of the lock pin 44 moves away from the inside of the flexible portion 86 of the plunger 82 toward the proximal end (direction of arrow A). This releases the locked state of the plunger 82 by the lock pin 44, and the plunger 82 starts to move toward the distal end (direction of arrow B) due to the elastic force of the injection spring 58.

[0148] 37 , when the plunger 82 starts to move distally, the four flanges 96 are pushed radially inward due to contact between the tapered distal end surface and the protrusions 38. This causes each flexible portion 86 to tilt radially inward relative to the pin body 46. As shown in FIG. 38 , when the plunger 82 moves further distally, the flanges 96 move over the protrusions 38 and continue to move distally.

[0149] When the flange 96 of the plunger 82 moves over the protrusion 38, the flange 96 is displaced radially inward, and then expands radially outward again due to the elastic restoring force of the flexible portion 86, so that the outer edge contacts the inner circumferential surface of the main body 31. At this time, as shown in Figure 19, because the outer diameter D1 of the flange 96 is slightly larger than the inner diameter D2 of the main body 31, a first recognition sound, which is a contact sound (smacking sound), is generated when the flange 96 contacts the main body 31.

[0150] After the plunger 82 starts moving toward the distal end and the flange 96 passes over the protrusion 38, the plunger 82 continues to move toward the distal end, causing the plunger 82 to start pushing the gasket 106. The medicinal solution M inside the outer tube 124 is pressed toward the distal end by the gasket 106. This causes the medicinal solution M to be expelled from the puncture needle 126, and administration of the medicinal solution M into the patient's subcutaneous tissue begins. As described above, when the plunger 82 starts moving toward the distal end and the flange 96 passes over the protrusion 38, a first recognition sound is generated as the flange 96 collides with the main body 31. The patient can confirm that administration of the medicinal solution M has begun by hearing the first recognition sound.

[0151] As the plunger 82 moves toward the distal end, it is guided by the guide ribs 34 of the sleeve body 22 inserted into the four slide grooves 92. As a result, when the plunger 82 moves toward the distal end, it moves only in the axial direction without rotating. The gasket 106 attached to the top member 88 is inserted into the outer cylinder 124 of the syringe 16.

[0152] After the administration of the medicinal liquid M has begun, the plunger 82 continues to move distally (in the direction of arrow B) at a constant speed due to the resilience of the injection spring 58. The medicinal liquid M is pushed out by the gasket 106, which moves distally within the outer tube 124, and the medicinal liquid M is expelled from the puncture needle 126. As the plunger 82 moves further distally, the flexible portion 86 reaches the proximal end of the end guide 68.

[0153] 21A , when the flange 96 comes into contact with the inclined guide portion 72, the flange 96 moves toward the tip end (in the direction of arrow B) while rotating clockwise along the inclined guide portion 72. In other words, when the plunger 82 moves along the inclined guide portion 72 of the end guide 68, a rotational force is applied to the plunger 82.

[0154] At the same time, as the plunger 82 rotates, as shown in Fig. 21B, the engagement piece 98 provided at the tip moves along the horizontal portion 110 in the guide groove 108 of the top member 88. Note that as shown in Fig. 39, the plunger 82 reaches the tip of each guide rib 34 of the sleeve body 22, and is released from the axial guide state by the slide groove 92 and the guide rib 34, allowing it to rotate.

[0155] 22A, flexible portion 86 moves toward the distal end while rotating along inclined guide portion 72 and reaches linear guide portion 74. At this point, as shown in FIG. 40, plunger 82 administers a predetermined amount of medicinal solution M in outer tube 124 into skin S via puncture needle 126, completing the administration of medicinal solution M.

[0156] 22B, before the administration of the medicinal solution M is completed, the engaging piece 98 of the rotating plunger 82 reaches the inclined portion 114 of the guide groove 108. The guide groove 70 functions as a guide means for moving the plunger 82 linearly toward the distal end (in the direction of arrow B) after rotating the plunger 82 by a predetermined amount.

[0157] After administration of the medicinal solution M is completed, the engaging piece 98 of the plunger 82 moves toward the vertical portion 112 while rotating along the inclined portion 114. Then, the engaging piece 98 of the plunger 82 moves again in the axial direction toward the tip (the direction of arrow B) by moving along the vertical portion 112. As shown in Figures 41A and 41B, the tip surface of the engaging piece 98 that has moved along the vertical portion 112 of the guide groove 108 comes into contact with the tip edge of the vertical portion 112, generating a second recognition sound that is a contact sound (smacking sound).

[0158] The second recognition sound is generated a predetermined time after the completion of administration of the medicinal liquid M. The generation of the second recognition sound allows the patient to confirm that administration of the medicinal liquid to the affected area (skin S) has been completed. After the patient confirms the second recognition sound, the patient moves the medicinal liquid administration device 10 away from the affected area.

[0159] That is, after the drug solution administration by the drug solution administration device 10 is completed, the plunger 82 is rotated by the guide groove 70 of the end guide 68 to slow down the speed of its axial movement. This delays the time it takes for the gasket 106 of the top member 88 connected to the plunger 82 to reach the tip of the outer tube 124. After a predetermined time has elapsed since the drug solution administration was completed, a second notification sound is generated to notify the user that the drug solution administration has been completed.

[0160] When the patient releases the pressing force against the skin S of the drug solution administration device 10, the elastic force of the sleeve spring 42 urges the slide member 64 toward the tip, as shown in Figure 42. Because the tip of the slide member 64 is in contact with the rib 119a of the needle cover 14, the slide member 64 pushes the needle cover 14 toward the tip, and moves toward the tip together with the needle cover 14 relative to the housing 12. The needle cover 14 moves to a position where the tip of the needle cover 14 is further distal than the puncture needle 126. As a result, the puncture needle 126 is completely covered by the needle cover 14.

[0161] 43 , the protruding piece 642 of the slide member 64 engages with the protruding portion 48a of the lock pin 44, causing the lock pin 44 to move distally (in the direction of arrow B) together with the slide member 64. As the lock pin 44 moves distally, the lock claw 62 engages with the lock groove 40 of the sleeve body 22. This restricts the proximal movement of the lock pin 44 relative to the sleeve body 22. Because the slide member 64 abuts against the arm portion 48 of the lock pin 44, the proximal movement of the slide member 64 is also restricted. Because the extension portion 119 (rib 119a) of the needle cover 14 abuts against the distal end of the slide member 64, the proximal movement of the needle cover 14 is also restricted.

[0162] Since the movement of the needle cover 14 toward the base end is restricted, even if a force toward the base end acts on the needle cover 14, the puncture needle 126 is not exposed to the outside by the needle cover 14, making it safe.

[0163] This embodiment has the following advantages.

[0164] As shown in FIG. 3 , the intermediate assembly Sa of the drug solution administration device 10 includes a first unit U1 and a second unit U2 attached to the first unit U1. The second unit U2 is temporarily fixed to the fixing portion 27 of the first unit U1 without the syringe 16 housed inside the first unit U1. The second unit U2 and the first unit U1 are permanently fixed to each other with the syringe 16 housed inside the housing 12 of the first unit U1. As a result, compared to when the first member, the second member, and the syringe filled with the drug solution are each made into a unit (assembly) and three assemblies are provided to the final assembly process, by temporarily fixing the first and second units U1 and U2 to one intermediate assembly Sa, the number of assemblies to be provided to the final assembly process can be reduced, thereby simplifying the assembly process of the drug solution administration device 10.

[0165] As shown in Fig. 6 , the second unit U2 has a first engagement portion 301 for temporary fixation and a second engagement portion 302 for final fixation. As shown in Fig. 17 , when the first unit U1 and the second unit U2 are temporarily fixed, the first engagement portion 301 engages with the fixing portion 27. As shown in Fig. 6 , when the first unit U1 and the second unit U2 are finally fixed, the second engagement portion 302 engages with the fixing portion 27. As a result, by engaging the first engagement portion 301 with the fixing portion 27, the first unit U1 and the second unit U2 can be temporarily fixed, and by engaging the second engagement portion 302 with the fixing portion 27, the first unit U1 and the second unit U2 can be effectively finally fixed.

[0166] The fixing portion 27 includes a temporary fixing portion 271 and a final fixing portion 272 provided at a position different from the temporary fixing portion 271. When the first unit U1 and the second unit U2 are temporarily fixed, the first engaging portion 301 engages with the temporary fixing portion 271. When the first unit U1 and the second unit U2 are finally fixed, the second engaging portion 302 engages with the final fixing portion 272. As a result, by engaging the first engaging portion 301 with the temporary fixing portion 271, the first unit U1 and the second unit U2 can be temporarily fixed, and by engaging the second engaging portion 302 with the final fixing portion 272, the first unit U1 and the second unit U2 can be effectively finally fixed.

[0167] The fixing portion 27 is a first hole 27A (recess) formed in the housing 12, and the temporary fixing portion 271 and the permanent fixing portion 272 are formed in different parts of the first hole 27A. This allows the temporary fixing portion 271 and the permanent fixing portion 272 to be provided in the same first hole 27A, making it easy to form the temporary fixing portion 271 and the permanent fixing portion 272.

[0168] The permanent fixing portion 272 is provided closer to the proximal end than the temporary fixing portion 271 in the axial direction of the housing 12. As a result, by moving the second unit U2 in the distal direction, the first engaging portion 301 can be disengaged from the temporary fixing portion 271 in the distal direction, and the second engaging portion 302 can be engaged with the permanent fixing portion 272.

[0169] The fixing portion 27 has a first region F1 in which a temporary fixing portion 271 is provided, and a second region F2 in which a permanent fixing portion 272 is provided and which is adjacent to the base end side of the first region F1 in the axial direction of the housing 12. The first region F1 is formed to be wider than the second region F2 in the circumferential direction of the housing 12. This makes it possible to easily provide the temporary fixing portion 271 and the permanent fixing portion 272 in one first hole 27A.

[0170] 2, the first engaging portion 301 has a first engaging protrusion 301A that is provided on the outer peripheral surface of the sleeve body 22 and can engage with the fixing portion 27, and the second engaging portion 302 has a second engaging protrusion 302A that is provided on the end cap 24 attached to the base end of the sleeve body 22 and can engage with the fixing portion 27. As a result, by engaging the first engaging protrusion 301A provided on the sleeve body 22 with the fixing portion 27, the first unit U1 and the second unit U2 can be temporarily fixed, and by providing the second engaging protrusion 302A on the end cap 24 and engaging it with the fixing portion 27, the first unit U1 and the second unit U2 can be effectively fixed permanently.

[0171] 7A and 7B , a plurality of fixing portions 27 are provided in the circumferential direction of the housing 12, and a plurality of first engaging portions 301 and a plurality of second engaging portions 302 are provided in the circumferential direction of the second unit U2. This makes it easy to align the first and second engaging portions 301, 302 with the fixing portions 27 in the circumferential direction of the housing 12 and the second unit U2 when inserting and temporarily fixing the second unit U2 inside the first unit U1.

[0172] 17 , the housing 12 has a receiving portion 28 formed of a second hole 28A disposed distally relative to the fixing portion 27. When the first unit U1 and the second unit U2 are finally fixed by the final fixing portion 272, the first engaging portion 301 is inserted into the receiving portion 28. As a result, when the first unit U1 and the second unit U2 are fixed, the first engaging portion 301 moves distally from the fixing portion 27 and is inserted into the receiving portion 28, thereby effectively preventing interference between the first engaging portion 301 and the housing 12.

[0173] 6 , the first engaging portion 301 for temporary fixation is an engaging portion used to temporarily fix the second unit U2 to the fixing portion 27 of the first unit U1 by engaging with the fixing portion 27 before the syringe 16 is housed in the housing 12 of the first unit U1. In an assembled state in which the syringe 16 is housed in the first unit U1 and the second unit U2 is permanently fixed to the fixing portion 27, the first engaging portion 301 disengages from the fixing portion 27 and the second engaging portion 302 engages with the fixing portion 27. As a result, compared to a configuration in which the first member, the second member, and the syringe filled with the medicinal solution are each formed into a unit and the three units are finally assembled, by temporarily fixing the first and second units U1 and U2 to form an intermediate assembly Sa, it is possible to reduce the number of units to be supplied to the assembly process and simplify the assembly process of the medicinal solution administration device 10.

[0174] The assembly includes a first step of removing the second unit U2 from the fixing portion 27 of the first unit U1 of the intermediate assembly Sa and separating it from the first unit U1 in the proximal direction, a second step of accommodating the syringe 16 inside the housing 12, and a third step of inserting the second unit U2 into the housing 12 and permanently fixing the second unit U2 to the fixing portion 27 of the first unit U1. As a result, compared to a configuration in which the first member, the second member, and the syringe filled with the medicinal solution are each formed into a unit and the three units are finally assembled, by forming the intermediate assembly Sa in which the first and second units U1 and U2 are temporarily fixed, it is possible to reduce the number of parts to be supplied to the assembly process and simplify the assembly process of the medicinal solution administration device 10.

[0175] The second unit U2 has a first engaging portion 301 for temporary fixation and a second engaging portion 302 for permanent fixation, and in a first step, the first engaging portion 301 is engaged with the fixing portion 27, resulting in a temporary fixation state, and the second unit U2 is removed by disengaging the first engaging portion 301 from the fixing portion 27. In a third step, the second engaging portion 302 is engaged with the fixing portion 27, resulting in a permanent fixation state of the second unit U2 relative to the first unit U1.

[0176] As a result, by engaging the first engaging portion 301 with the fixing portion 27, the first unit U1 and the second unit U2 can be temporarily fixed, and by engaging the second engaging portion 302 with the fixing portion 27, the first unit U1 and the second unit U2 can be effectively fixed in place with the syringe 16 housed inside.

[0177] 26 , the medical device package P includes the intermediate assembly Sa of the drug solution administration device 10 and the packaging container 156 that houses the intermediate assembly Sa. Therefore, compared to a case where the first unit U1 and the second unit U2 are each housed individually in the packaging container 156, the intermediate assembly Sa, in which the first and second units U1 and U2 are temporarily fixed, can be housed integrally in the packaging container 156. This allows for space-saving storage of the intermediate assembly Sa.

[0178] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention.

Claims

1. An intermediate assembly of a medicinal liquid administration device comprising a first unit and a second unit attached to the first unit, wherein the first unit has a hollow cylindrical housing, the housing being capable of housing a syringe filled with medicinal liquid, the second unit having a drive unit that urges a gasket of the syringe toward the tip of the housing, and is attached to a fixing part provided at the base end of the housing of the first unit, and at least a portion of the second unit being housed inside the housing, the second unit being provisionally fixed to the fixing part of the first unit when the syringe is not housed inside the first unit, the second unit being able to be removed from the fixing part of the first unit to release the provisionally fixed state, and the second unit and the first unit being properly fixed in a state in which the syringe is housed inside the housing of the first unit.

2. An intermediate assembly for a drug solution administration device as described in claim 1, wherein the second unit has a first engagement portion for temporary fixation and a second engagement portion for final fixation, and when the first unit and the second unit are in a temporary fixed state, the first engagement portion engages with the fixed portion, and when the temporary fixed state between the first unit and the second unit is released and when the first unit and the second unit are in a final fixed state, the first engagement portion disengages from the fixed portion and the second engagement portion engages with the fixed portion.

3. An intermediate assembly for a drug solution administration device as described in claim 2, wherein the fixing portion has a temporary fixing portion and a final fixing portion provided at a position different from the temporary fixing portion, and when the first unit and the second unit are in a temporarily fixed state, the first engaging portion engages with the temporary fixing portion, and when the first unit and the second unit are in a final fixed state, the first engaging portion disengages from the temporary fixing portion and the second engaging portion engages with the final fixing portion.

4. An intermediate assembly for a medicinal liquid administration device as described in claim 3, wherein the fixing portion is a hole or recess formed in the housing, and the temporary fixing portion and the actual fixing portion are formed in different portions of the hole or recess.

5. An intermediate assembly for a drug solution administration device according to claim 4, wherein the permanent fixing portion is provided on the base end side of the temporary fixing portion in the axial direction of the housing.

6. An intermediate assembly for a drug solution administration device as described in claim 5, wherein the fixing portion has a first region in which the temporary fixing portion is provided and a second region adjacent to the base end side of the first region in the axial direction of the housing and in which the permanent fixing portion is provided, and the first region is formed wider than the second region in the circumferential direction of the housing.

7. An intermediate assembly for a medicinal solution administration device as described in claim 2, wherein the fixing portion is a hole or recess formed in the housing, the first engagement portion is attached to the base end of the housing and has a first engagement projection provided on the outer peripheral surface of a sleeve body housed inside the housing and capable of engaging with the fixing portion, and the second engagement portion is provided on an end cap attached to the base end of the sleeve body and has a second engagement projection capable of engaging with the fixing portion.

8. An intermediate assembly for a medicinal solution administration device according to any one of claims 2 to 7, wherein the fixing portion is provided in a plurality of portions in the circumferential direction of the housing, and each of the first engagement portion and the second engagement portion is provided in a plurality of portions in the circumferential direction of the second unit.

9. An intermediate assembly for a medicinal liquid administration device as claimed in any one of claims 3 to 6, wherein the housing has a receiving portion consisting of a hole or recess arranged in a distal direction relative to the fixing portion, and when the first unit and the second unit are fixed by the main fixing portion, the first engagement portion is inserted into the receiving portion.

10. A drug solution administration device comprising: a first unit having a hollow cylindrical housing; a syringe housed within the housing and filled with a drug solution; and a second unit having a drive unit that urges a gasket of the syringe toward the tip of the housing, the second unit being attached to the first unit and at least a portion of which is housed inside the housing, wherein a base end of the housing of the first unit has a fixing portion, the second unit having a first engaging portion for temporary fixation and a second engaging portion for final fixation, the first engaging portion is an engaging portion used to temporarily fix the second unit to the fixing portion of the first unit by engaging with the fixing portion before the syringe is housed in the housing of the first unit, and in an assembled state in which the syringe is housed in the housing and the second unit is final fixed to the fixing portion of the first unit, the first engaging portion is detached from the fixing portion and the second engaging portion is engaged with the fixing portion.

11. A method for assembling a medicinal liquid administration device using the intermediate assembly described in claim 1, comprising: a first step of removing the second unit from the fixing portion of the first unit of the intermediate assembly and detaching it in a base end direction from the first unit; a second step of inserting the syringe from the base end of the first unit toward the tip end into the interior of the housing and accommodating the syringe in the housing; and a third step of inserting the second unit from the base end of the first unit into the interior of the housing and finally fixing the second unit to the fixing portion of the first unit.

12. A method for assembling a medicinal liquid administration device as described in claim 11, wherein the second unit has a first engagement portion for temporary fixation and a second engagement portion for final fixation, and in the first step, the second unit is removed from a temporary fixed state in which the first engagement portion is engaged with the fixed portion by disengaging the first engagement portion from the fixed portion, and in the third step, the second engagement portion is engaged with the fixed portion, thereby achieving a final fixed state of the second unit relative to the first unit.

13. A medical device package comprising: an intermediate assembly of the drug solution administration device according to claim 1; and a packaging container for accommodating said intermediate assembly.