WO2016132936A1

WO2016132936A1 - Liquid drug administration device

Info

Publication number: WO2016132936A1
Application number: PCT/JP2016/053586
Authority: WO
Inventors: 近藤晃
Original assignee: テルモ株式会社
Priority date: 2015-02-20
Filing date: 2016-02-05
Publication date: 2016-08-25

Abstract

The present invention relates to a liquid drug administration device. The liquid drug administration device (10) continuously or intermittently administers a liquid drug, filled into a cylindrical body (36), into a living body as a result of a pressing action on a plunger (38). The liquid drug administration device (10) comprises: a nut section (42) that, as a result of rotation of a feed screw shaft (40), moves from an initial position where same is not in contact with the plunger (38) to a usage position where same is in contact with the plunger (38) and the plunger (38) can be pressed; and a travel restriction section (72) that restricts movement of the nut section (42) towards the tip side of the plunger (38), in the usage position.

Description

Chemical solution administration device

The present invention relates to a portable drug solution administration device that continuously or intermittently administers a drug solution filled in a cylinder into a living body under the action of a plunger.

As this type of chemical solution administration device, for example, Japanese Patent Application Publication No. 2010-535057 discloses a configuration (first configuration) in which a plunger and a drive unit are screw-engaged and the plunger is moved under the rotational action of the screw. (See FIG. 17a and FIG. 17b of JP 2010-535057 A). In addition, this special table 2010-535057 discloses a configuration (second configuration) in which a piston provided in a cylinder and a plunger rod that presses the piston toward the tip side are detachable (second configuration). (See FIG. 15a and FIG. 15b of JP-T 2010-535057).

By the way, in general, the chemical solution is not filled in the cylinder before using the chemical solution administration device. Therefore, the user needs to fill the cylinder with an appropriate amount of the chemical solution from the chemical solution container such as a vial before using the chemical solution administration device.

However, when the first configuration of Japanese Patent Application Publication No. 2010-535057 is adopted, it is necessary to rotate the screw when changing the position of the plunger with respect to the cylindrical body. It may not be possible to fill quickly.

In addition, when the second configuration of Japanese Patent Publication No. 2010-535057 is adopted, the plunger rod can be separated from the piston, so that when the chemical liquid administration device is used (during chemical administration), the piston is There is a possibility that the plunger rod moves away from the plunger rod and is displaced to the distal end side, and free flow occurs (the drug solution in the cylinder is administered unintentionally).

The present invention has been made in consideration of such problems, and provides a chemical solution administration device that can easily and quickly fill a cylinder with an appropriate amount of chemical solution and prevent free flow. The purpose is to do.

In order to achieve the above object, a drug solution administration device according to the present invention is a portable drug solution administration device that continuously or intermittently administers a drug solution filled in a cylinder into a living body under the action of a plunger. , A feed screw shaft extending along the axial direction of the plunger, a drive unit for rotationally driving the feed screw shaft, and the plunger under the rotational action of the feed screw shaft in a state of being screwed to the feed screw shaft A nut portion that contacts the plunger from an initial position that does not contact the plunger and moves to a use position where the plunger can be pressed; and is provided on the plunger, engages with the nut portion at the use position, and engages with the nut portion. And a movement restricting portion for restricting movement of the plunger toward the distal end side with respect to the nut portion in a combined state.

According to the liquid medicine administration device of the present invention, when filling the liquid medicine into the cylinder, the nut portion at the initial position does not contact the plunger, so that the position of the plunger can be manually changed according to the amount of liquid medicine to be filled. it can. As a result, it is possible to easily and quickly fill the cylinder with an appropriate amount of the chemical solution. Further, even when a change in atmospheric pressure occurs during use of the drug solution administration device, the movement restricting portion restricts the movement of the plunger toward the distal end side with respect to the nut portion, so that free flow can be prevented.

In the above-described drug solution administration device, the movement restricting portion is provided on the plunger and has a flexible leg extending along the axial direction of the plunger, and is provided on the leg and provided on the nut portion. A claw portion that can contact a receiving surface directed in a direction opposite to the traveling direction with respect to the plunger may be included.

According to such a configuration, when the nut portion is moved from the initial position to the use position, the leg portion can be bent and the claw portion can be guided and brought into contact with the receiving surface of the nut portion. Thereby, the movement to the front end side of the plunger with respect to a cylinder can be controlled reliably.

In the medicinal solution administration device, a through hole through which the claw portion is inserted is formed in the nut portion, and a tapered nail side contact surface that contacts a wall surface forming the through hole is formed in the claw portion. May be.

According to such a configuration, the claw side contact surface can be slid to the wall surface constituting the through hole of the nut portion, so that the resistance force when the claw portion is passed through the through hole can be made relatively small. Therefore, it is possible to suppress the plunger from being pushed by the nut portion when the claw portion is passed through the through hole and progressing to the distal end side.

In the above-described drug solution administration device, a tapered hole-side contact surface that contacts the nail-side contact surface may be formed on the wall surface forming the through-hole. According to such a structure, the resistance force at the time of letting a nail | claw part pass through a through-hole can be reduced more.

In the above chemical solution administration device, the through hole may expand toward the distal end side of the plunger. According to such a configuration, the claw portion can be easily introduced into the through hole.

In the drug solution administration device, the feed screw shaft may be disposed coaxially with the plunger, and a pair of the claw portions may be provided so as to face each other with the feed screw shaft interposed therebetween.

According to such a configuration, the medicinal solution administration device can be configured in a compact manner, and the claw portion can be efficiently suppressed from being detached from the receiving surface of the nut portion.

According to the present invention, since the position of the plunger can be manually changed when filling the cylinder with the chemical solution, an appropriate amount of the chemical solution can be easily and quickly filled into the cylinder. Moreover, when using a chemical | medical solution administration apparatus, since the movement to the front end side of the plunger with respect to a nut part is controlled by the movement control part, a free flow can be prevented.

It is a disassembled perspective view of the chemical | medical solution administration apparatus which concerns on this invention. It is a top view of the disposable part of FIG. It is a perspective view, such as a plunger and a nut part. It is a schematic diagram explaining the 1st chemical | medical solution filling method. It is a top view of the disposable part which comprises the chemical | medical solution administration apparatus at the time of use. It is a schematic diagram explaining the 2nd chemical | medical solution filling method. 7A is a cross-sectional explanatory view of the disposable part according to the first modification, FIG. 7B is a cross-sectional explanatory view of the disposable part according to the second modification, and FIG. 7C is a cross-sectional description of the disposable part according to the third modification. FIG.

Hereinafter, preferred embodiments of the drug solution administration device according to the present invention will be described with reference to the accompanying drawings.

The drug solution administration device 10 according to the present embodiment is a portable drug solution administration device 10 that continuously or intermittently administers a drug solution filled in a cylindrical body 36 into a living body under the pressing action of a plunger 38. It is configured as a formula insulin pump. However, the drug solution administration device 10 is not limited to the patch type, and may be a tube type or the like.

As shown in FIG. 1, the drug solution administration device 10 includes a cradle 14 provided with a seal portion 12 that can be attached to the skin of a user (patient), and a drug solution administration device body 16 that is detachably provided on the cradle 14. It has.

The cradle 14 has a substantially rectangular support plate 18 to which the seal portion 12 is fixed, and a locking wall 20 provided on the outer peripheral edge of the support plate 18. A cannula mechanism 22 having a cannula placed in the living body using a puncture mechanism (not shown) is attached to the corner of the support plate 18. The locking wall 20 is formed with a mounting hole 26 into which the mounting claw 24 of the drug solution administration device body 16 is fitted.

The drug solution administration device main body 16 has a disposable disposable part 28 and a reusable reuse part 30. The disposable part 28 includes a flat box-shaped base part 32 opened on one side (Z2 direction). The base portion 32 has a substantially rectangular shape corresponding to the support plate 18 in plan view. The base portion 32 is provided with a cannula accommodating portion 34 in which the cannula mechanism 22 is accommodated when the drug solution administration device main body 16 is attached to the cradle 14.

As shown in FIG. 2, the base portion 32 includes a cylindrical body 36 filled with a chemical solution, a plunger 38 provided in the cylindrical body 36, a feed screw shaft 40 disposed coaxially with the plunger 38, A nut portion 42 screwed to the feed screw shaft 40 is provided.

The cylindrical body 36 extends in a cylindrical shape along the longitudinal direction (X1, X2 direction) of the base portion 32. The distal end portion (end portion in the X1 direction) of the cylindrical body 36 has an outer diameter and an inner diameter that are reduced toward the distal end. At the tip of the cylindrical body 36, an introduction port 44 (see FIG. 1) for introducing the chemical liquid into the cylindrical body 36 and a lead-out port 46 for guiding the chemical liquid in the cylindrical body 36 are formed. Yes. The introduction port 44 is closed by a closing member 48 made of rubber or the like (see FIG. 4). The outlet port 46 communicates with the outlet pipe 50 that guides the fluid in the cylindrical body 36 to the cannula mechanism 22.

The plunger 38 is integrally formed of a resin material or the like, and is provided in the cylinder 36 so as to be slidable in a liquid-tight manner along the axial direction of the cylinder 36. As shown in FIGS. 2 and 3, the plunger 38 has a plunger main body 52 that constitutes the distal end side, and a pusher 54 that is provided on the plunger main body 52 and constitutes the rear end side. A pair of packings 56 are attached to the rear end side of the plunger body 52 formed in a cylindrical shape. The distal end portion of the plunger main body 52 has a substantially conical shape, and the outer diameter is reduced toward the distal end.

The pusher 54 includes a pair of first extending portions 58 and a pair of second extending portions 60 extending from the plunger main body 52 to the outside of the cylindrical body 36 rearward (X2 direction), and a first extending portion. 58 and a pair of connecting portions 62 that connect the second extending portion 60.

The pair of first extending portions 58 are disposed apart from each other along the short direction (Y1, Y2 direction) of the base portion 32. A first abutting surface 64 with which the nut portion 42 abuts at the rear end portion of each first extending portion 58, and an operation for assisting the sliding operation of the plunger 38 when the cylindrical body 36 is filled with a chemical solution. A first engagement portion 66 with which the auxiliary tool 230 (see FIG. 6) can be engaged is provided.

The pair of second extending portions 60 are spaced apart from each other along the short direction of the base portion 32. A rear end portion of each second extending portion 60 is provided with a second abutting surface 68 with which the nut portion 42 abuts and a second engaging portion 70 with which the operation assisting tool 230 can be engaged. . The first extension part 58 and the second extension part 60 face each other in a state of being separated from each other along the height direction (Z1, Z2 direction) of the base part 32. The pusher 54 of the plunger 38 configured in this manner is provided with a movement restricting portion 72 that restricts the movement of the distal end side of the plunger 38 relative to the nut portion 42 while being engaged with the nut portion 42. The detailed configuration of the movement restricting unit 72 will be described later.

The feed screw shaft 40 is rotationally driven by the drive unit 76 with its end in the X1 direction being pivotally supported by a bearing 74 provided in the base portion 32. The drive unit 76 includes a battery 78 as a power source, a motor 80 driven by the battery 78, a gear box (power transmission mechanism) 82 that transmits the rotational driving force of the motor 80 at a reduced speed, and an output gear of the gear box 82. A spur gear 86 that meshes with 84 is fixed, and has a transmission shaft 88 that is locked to the feed screw shaft 40 so as to be integrally rotatable.

In the present embodiment, the battery 78 and the transmission shaft 88 are provided on the base portion 32 constituting the disposable portion 28, and the motor 80 and the gear box 82 are provided on the lid 90 (see FIG. 1) constituting the reuse portion 30. Yes. Thus, the cost of the disposable unit 28 can be reduced by using the motor 80 and the gear box 82 as the reuse unit 30. The lid 90 is detachably provided on the base portion 32 so as to close the opening of the base portion 32.

The battery 78 is provided with a terminal 92 that is electrically connected to the motor 80 of the reuse unit 30 when the reuse unit 30 is attached to the disposable unit 28. The transmission shaft 88 is pivotally supported by a pair of bearings 94 provided on the base portion 32 in a state of being arranged coaxially with the feed screw shaft 40. In the present embodiment, the transmission shaft 88 is screw-engaged with the feed screw shaft 40. However, the engagement structure between the transmission shaft 88 and the feed screw shaft 40 can be arbitrarily set.

The movement restricting portion 72 is formed integrally with the plunger 38 by a resin material or the like, and is provided at a pair of leg portions 96 extending rearward from each connecting portion 62 and a rear end portion of each leg portion 96. And a pair of claw portions 98. A feed screw shaft 40 is disposed between the pair of leg portions 96. Each leg part 96 has flexibility, and can be bent along the thickness direction (Y1, Y2 direction).

The pair of claw portions 98 are opposed to each other with the feed screw shaft 40 being sandwiched between the first engagement portion 66 and the second engagement portion 70. The claw portion 98 projects outward from the rear end portion of the leg portion 96 (the side opposite to the side where the feed screw shaft 40 is located). On the outer surface of the claw portion 98, a tapered claw-side contact surface 100 that is inclined inward (side on which the feed screw shaft 40 is located) in the X2 direction is formed. The claw portion 98 is formed narrower in the X2 direction (the dimensions in the Z1 direction and the Z2 direction are smaller).

The nut portion 42 is integrally formed of a resin material, and includes a nut portion main body 102 formed in a substantially rectangular parallelepiped shape and a slide portion 104 provided on the nut portion main body 102. The nut portion main body 102 is formed with a screw hole 106 into which the feed screw shaft 40 is screwed and a pair of rectangular through holes 108 formed so as to sandwich the screw hole 106 from both sides and through which the claw portion 98 is inserted. Yes.

The screw hole 106 is located substantially at the center of the nut portion main body 102. A tapered hole-side contact surface 110 that contacts the claw-side contact surface 100 is formed on the wall surface constituting the through-hole 108 (see FIG. 2). That is, the hole-side contact surface 110 is inclined outward toward the distal end side of the plunger 38. Further, the through hole 108 expands toward the distal end side of the plunger 38. Thereby, the claw portion 98 can be easily introduced into the through hole 108. However, the through hole 108 can be arbitrarily formed.

A reinforcing cover 112 made of, for example, a metal material is attached to the outer surface of the nut body 102. The slide portion 104 slides with respect to the guide wall 114 having a substantially L-shaped cross section provided on the base portion 32 and extending along the axial direction of the plunger 38. Thereby, the nut part 42 moves smoothly along the axial direction of the feed screw shaft 40 under the rotating action of the feed screw shaft 40.

The drug solution administration device 10 according to the present embodiment is basically configured as described above, and the operation and effects thereof will be described next.

First, the user takes out the disposable part 28 to which the adapter 200 is attached from the packaging container. In this state, the cylindrical body 36 of the disposable part 28 is not filled with the chemical solution, and the nut part 42 is in an initial position where it does not contact the plunger 38 (see FIG. 2). As shown in FIG. 4, one end portion of the introduction needle 202 of the adapter 200 passes through the closing member 48 and is positioned in the cylindrical body 36, and the connection passage 206 of the adapter 200 communicates with the inner hole of the outlet pipe 50. To do.

Next, the user operates the pusher 54 to slide the plunger 38 along the axial direction with respect to the cylinder 36 so that an appropriate amount of the chemical solution can be filled in the cylinder 36. At this time, since the nut portion 42 is in the initial position where it does not come into contact with the plunger 38, the position of the plunger 38 can be manually changed according to the filling amount of the chemical solution. Note that the user may operate by directly picking the pusher 54, or may operate the pusher 54 using an operation assisting tool 230 shown in FIG.

Thereafter, the disposable part 28 to which the adapter 200 is attached is set in the filling machine 210 so that the X1 direction thereof is vertically upward. In this state, the connection passage 206 of the adapter 200 communicates with the cylinder 214 via the suction passage 212 of the filling machine 210.

Then, a chemical solution container 222 such as a vial in which the chemical solution is hermetically stored by the stopper member 220 is attached to the adapter 200. As a result, the other end portion of the introduction needle 202 of the adapter 200 passes through the plug member 220 and is positioned in the chemical solution container 222, and the end portion of the air needle 204 of the adapter 200 passes through the plug member 220 and is stored in the chemical solution container 222. Located in.

Subsequently, the piston 216 in the cylinder 214 of the filling machine 210 is driven to suck the air in the cylinder 36 into the cylinder 214 via the outlet pipe 50, the connection passage 206, and the suction passage 212. As a result, the chemical solution in the chemical solution container 222 is introduced into the cylindrical body 36 through the introduction needle 202 and air is introduced into the chemical solution container 222 through the air needle 204. And the filling of the chemical | medical solution in the cylinder 36 is completed in the stage where the storage space in the cylindrical body 36 was satisfy | filled with the chemical | medical solution.

Thus, when the chemical liquid is filled into the cylindrical body 36, the nut portion 42 in the initial position does not come into contact with the plunger 38, so that the position of the plunger 38 can be manually changed according to the filling amount of the chemical liquid. Thereby, it is possible to easily and quickly fill the cylindrical body 36 with an appropriate amount of the chemical solution.

Next, the user removes the disposable part 28 from the filling machine 210 and removes the adapter 200 from the disposable part 28, and then attaches the reuse part 30 to the disposable part 28. As a result, the power of the battery 78 of the disposable unit 28 is supplied to the components of the reuse unit 30, and the output gear 84 of the gear box 82 of the reuse unit 30 meshes with the spur gear 86 of the disposable unit 28.

Thereafter, priming of the drug solution administration device main body 16 is performed. Specifically, the motor 80 is rotated by operating a remote controller (not shown). Then, since the rotational driving force of the motor 80 is transmitted to the feed screw shaft 40 via the gear box 82, the spur gear 86, and the transmission shaft 88, the feed screw shaft 40 rotates and the nut portion 42 slides on the guide wall 114. While proceeding to the plunger 38 side.

When the hole side contact surface 110 of the nut part 42 contacts the claw side contact surface 100 of the movement restricting part 72, the leg part 96 bends so that the pair of claw parts 98 come close to each other. When the claw portion 98 passes through the through hole 108, the claw portion 98 returns to its original position, thereby contacting the receiving surface 116 of the nut portion 42 that is directed in the direction opposite to the traveling direction with respect to the plunger 38. At this time, the reinforcing cover 112 of the nut portion 42 contacts the first contact surface 64 and the second contact surface 68 of the plunger 38. Thereby, the nut part 42 becomes a use position which can press the plunger 38 to the front end side (refer FIG. 5).

Thereafter, by further advancing the nut portion 42, the chemical solution in the cylindrical body 36 is pressed by the plunger 38, the inner hole of the outlet tube 50 is filled with the chemical solution, and the priming is completed.

Subsequently, the user attaches the seal portion 12 to a predetermined position on the skin, and uses the puncture mechanism to place the cannula locked to the cradle 14 in the living body. And the chemical | medical solution in the cylinder 36 is continuously or intermittently administered in the living body by mounting | wearing the cradle 14 with the chemical | medical solution administration apparatus main body 16 and carrying out rotation control of the motor 80. FIG.

In such a chemical solution administration device 10, a force toward the distal end side of the cylindrical body 36 may act on the plunger 38 due to a change in atmospheric pressure. However, even in such a case, the movement of the plunger 38 relative to the front end side of the plunger 38 with respect to the nut portion 42 is restricted by the claw portion 98 of the movement restricting portion 72 coming into contact with the receiving surface 116 of the nut portion 42. Therefore, the plunger 38 does not move to the tip side. Thereby, it can prevent that the chemical | medical solution in the cylinder 36 is administered in the living body unintentionally (free flow).

According to the drug solution administration device 10 according to the present embodiment, when the nut part 42 is moved from the initial position to the use position, the claw part 98 is guided to the receiving surface 116 of the nut part 42 by bending the leg part 96. Can be contacted. Thereby, the movement to the front end side of the plunger 38 with respect to the cylinder 36 can be controlled reliably.

In this embodiment, since the claw-side contact surface 100 having a tapered shape is formed on the claw portion 98, the resistance force when the claw portion 98 is passed through the through hole 108 can be made relatively small. Therefore, it is possible to prevent the plunger 38 from being pushed by the nut portion 42 and traveling toward the distal end side when the claw portion 98 is passed through the through hole 108. In addition, since the tapered hole side contact surface 110 that contacts the claw side contact surface 100 is formed on the wall surface constituting the through hole 108, the resistance force when the claw portion 98 is passed through the through hole 108 is further reduced. be able to.

Further, since the feed screw shaft 40 is disposed coaxially with the plunger 38 and the pair of claws 98 are provided so as to face each other with the feed screw shaft 40 interposed therebetween, the drug solution administration device 10 can be configured compactly. In addition, the claw portion 98 can be efficiently prevented from being detached from the receiving surface 116 of the nut portion 42.

By the way, in the chemical solution administration device 10 according to the present embodiment, the filling machine 210 may not be at the user's hand when the cylindrical body 36 is filled with the chemical solution. In such a case, it is also possible to fill the cylindrical body 36 with a chemical solution as follows. That is, first, the plate portion of the operation assisting device 230 with the pair of engaging legs 232 of the operation assisting device 230 shown in FIG. 6 engaged with the first engaging portion 66 and the second engaging portion 70 of the pusher 54. 234 is picked and the plunger 38 is moved to the foremost position. In this state, the connection passage 206 of the adapter 200 is closed by the lid member 208.

Thereafter, the chemical solution container 222 is mounted on the adapter 200 with the disposable portion 28 standing so that the X1 direction thereof is vertically upward, and the plunger 38 is moved backward using the operation assisting tool 230. As a result, the pressure in the cylindrical body 36 is reduced, so that the chemical liquid in the chemical liquid container 222 is introduced into the cylindrical body 36 through the introduction needle 202. Then, when the appropriate amount of the chemical solution is filled into the cylindrical body 36, the backward movement of the plunger 38 is stopped. Even in this case, since the nut portion 42 is in the initial position where it does not come into contact with the plunger 38, an appropriate amount of the chemical solution can be easily and quickly filled into the cylindrical body 36. In such a filling method, the user can directly pick the pusher 54 and move the plunger 38 without using the operation assisting tool 230.

The chemical solution administration device 10 according to the present embodiment is not limited to the configuration described above. The drug solution administration device 10 may include disposable parts 28A to 28C according to the first to third modifications shown in FIGS. 7A to 7C.

As shown in FIG. 7A, the disposable part 28A according to the first modified example includes a side where the feed screw shaft 40 is located from a position of the leg part 96 that is a predetermined distance away from the claw part 98 toward the tip side (X1 direction). Has a convex portion 120 that protrudes to the opposite side and contacts the nut portion 42. In this case, it is possible to reduce the pressure acting on the nut portion 42 during the administration of the chemical solution, so that the nut portion 42 can be prevented from being deformed when the plunger 38 is pressed.

As shown in FIG. 7B, the disposable part 28B according to the second modified example includes a nut part 122 in which the through hole 108 is not formed, and a receiver that goes over the nut part 122 from the outside and is oriented in the X2 direction of the nut part 122. And a movement restricting portion 126 having a claw portion 124 that contacts the surface 123. Further, on each surface where the receiving surface 123 and the claw portion 124 come into contact, there are provided a protruding portion and a receiving portion (not shown) that engage with each other. In this case, since it is not necessary to form the through-hole 108 in the nut part 122, the rigidity of the nut part 122 can be improved.

As shown in FIG. 7C, the disposable part 28C according to the third modification includes a nut part 128 in which the through hole 108 is not formed. The nut portion 128 includes a leg portion 132 that extends from the nut portion main body 130 toward the distal end side (X1 direction), and a claw portion 134 that is provided at the distal end portion of the leg portion 132. A movement restricting portion 136 that engages with the claw portion 134 is provided at the rear end portion of the plunger 38. Even with such a configuration, movement of the distal end side of the plunger 38 with respect to the nut portion 128 can be restricted at the use position of the nut portion 128.

Claims

A portable drug solution administration device (10) for continuously or intermittently administering a drug solution filled in a cylindrical body (36) into a living body under the pressing action of a plunger (38),
A lead screw shaft (40) extending along the axial direction of the plunger (38);
A drive unit (76) for rotationally driving the feed screw shaft (40);
The plunger (38) comes into contact with the plunger (38) from the initial position where it does not contact the plunger (38) under the rotational action of the feed screw shaft (40) in a state of being screwed to the feed screw shaft (40). A nut portion (42, 122, 128) that moves to a useable position,
It is provided in the plunger (38), engages with the nut part (42, 122, 128) in the use position, and engages with the nut part (42, 122, 128) in the state of being engaged with the nut part (42, 122, 128). 122, 128) and a movement restricting portion (72, 126, 136) for restricting movement of the plunger (38) toward the distal end side with respect to 122, 128).
The medicinal-solution administration device (10) according to claim 1,
The movement restricting portions (72, 126) are provided on the plunger (38) and have flexible leg portions (96) extending along the axial direction of the plunger (38),
A claw portion (98) provided on the leg portion (96) and capable of contacting a receiving surface (116, 123) of the nut portion (42, 122) oriented in a direction opposite to the traveling direction with respect to the plunger (38). , 124), and a chemical liquid administration device (10).
The medicinal-solution administration device (10) according to claim 2,
The nut part (42) is formed with a through hole (108) through which the claw part (98) is inserted,
The drug solution administration device (10), wherein the claw portion (98) is formed with a tapered claw side contact surface (100) that contacts a wall surface constituting the through hole (108).
The medicinal-solution administration device (10) according to claim 3,
A drug solution administration device (10), wherein a taper-shaped hole side contact surface (110) contacting the nail side contact surface (100) is formed on a wall surface constituting the through hole (108). .
In the medicinal-solution administration device (10) according to claim 3 or 4,
The medicinal-solution administration device (10), wherein the through hole (108) is enlarged toward the distal end side of the plunger (38).
The drug solution administration device (10) according to any one of claims 2 to 5,
The feed screw shaft (40) is disposed coaxially with the plunger (38),
A pair of the claw portions (98, 124) are provided so as to face each other across the feed screw shaft (40).