Adjustment device and syringe

Abstract

The present invention provides an adjustment device and a syringe that can reliably adjust and dispense the amount of contents contained in the syringe. [Solution] A syringe body comprising a barrel and a plunger is configured to adjust the discharge amount and includes a plunger restricting section that restricts the axial movement of the plunger toward the tip, and a position setting mechanism that sets the restricting position of the plunger restricting section. The position setting mechanism comprises a plurality of positioning sections arranged to have different axial positions, and a locking section that can lock onto each positioning section in the axial direction. The plurality of positioning sections and the locking section are configured to be relatively movable, and the restricting position of the plunger restricting section is set when the plurality of positioning sections and the locking section move relative to each other and the locking section locks onto one of the positioning sections and is positioned.

Description

Technical Field

[0001] The present invention relates to an adjustment device for adjusting the discharge amount of a chemical solution filled inside a syringe, and a syringe provided with this adjustment device.

Background Art

[0002] Conventionally, a syringe for discharging a chemical solution or the like has been known (Patent Document 1). As shown in FIG. 28, this syringe 900 includes an outer cylinder 910 that can be filled with a liquid inside, a pusher 920 that can move along the longitudinal direction of the outer cylinder 910 inside the outer cylinder 910, and a mounting tool 930 that can be attached to the outer cylinder 910. A plurality of convex portions 926A and concave portions 926B arranged in the longitudinal direction are formed on the pusher 920. The mounting tool 930 includes an annular portion 931 that can be inserted through the pusher 920 from the proximal end direction of the pusher 920 and attached to the outer cylinder 910, a protrusion portion 932 that can slide sequentially with respect to at least a plurality of convex portions 926A as the pusher 920 moves or can contact the convex portions 926A to stop them, and a rotation restricting portion 933 that contacts the pusher 920 and restricts the rotation of the pusher 920 with respect to the outer cylinder 910.

[0003] According to this syringe 900, the mounting tool 930 can be attached to the outer cylinder 910 from the proximal end direction of the pusher 920, and it is possible to selectively attach the mounting tool 930 only when necessary. And since the mounting tool 930 has the protrusion portion 932 and the rotation restricting portion 933, even in the case of the mounting tool 930 in a selectively attached form, the rotation of the pusher 920 is restricted by the rotation restricting portion 933, and contact of the protrusion portion 932 with the convex portion 926A is ensured. Therefore, when the protrusion portion 932 sequentially contacts the convex portion 926A, the resistance force received by the pusher 920 from the protrusion portion 932 is transmitted to the finger, and the liquid feeding of the target amount becomes easy.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] However, with the syringe 900 described above, even though the resistance force received by the plunger 920 from the projection 932 was transmitted to the finger, the user may push the plunger 920 too far or too far in to achieve the desired volume, making accurate fluid delivery difficult.

[0006] The present invention aims to provide an adjustment device and a syringe that can reliably adjust and dispense the amount of contents contained in the syringe. [Means for solving the problem]

[0007] The adjustment device of the present invention is configured to adjust the discharge amount in a syringe body comprising a barrel capable of containing a substance, a barrel including a tip portion located on the axial end side capable of discharging the substance and a base portion located on the axial base side with an opening that communicates with the interior, and a plunger inserted into the barrel from the opening and moving toward the axial end side to discharge the substance from the tip portion, and includes a plunger restricting part that restricts the movement of the plunger toward the axial end side, and a position setting mechanism that sets the restricting position of the plunger restricting part, wherein the position setting mechanism comprises a plurality of positioning parts arranged at different axial positions and a locking part that can lock onto each positioning part in the axial direction, the plurality of positioning parts and the locking part are configured to be relatively movable, and the restricting position of the plunger restricting part is set when the plurality of positioning parts and the locking part move relative to each other and the locking part locks onto one of the positioning parts and is positioned.

[0008] With this configuration, a locking part that is relatively movable relative to multiple positioning parts is positioned by locking it axially to each positioning part, thereby setting the restricted position of the plunger restricting part. In the position setting mechanism, the positioning part and the locking part are moved relative to each other, and the locking part is locked to one positioning part, thereby setting the restricted position of the plunger restricting part. Therefore, the restricted position can be accurately set to adjust the discharge amount and the desired amount of contents can be discharged.

[0009] Furthermore, the adjustment device includes a plunger-side member having a plunger restricting portion that abuts the plunger in the axial direction to restrict the axial movement of the plunger toward the tip, and a barrel-side member having a barrel contact portion that abuts the barrel in the axial direction to restrict the barrel's movement toward the tip, wherein one of the plunger-side member and the barrel-side member has the plurality of positioning portions, and the other of the plunger-side member and the barrel-side member has the locking portion, and the plurality of positioning portions and the locking portion may move relative to each other as the plunger-side member and the barrel-side member move relative to each other while the plunger-side member and the barrel-side member are mounted on the syringe body.

[0010] With this configuration, the relative movement between the plunger-side member and the barrel-side member causes multiple positioning parts and locking parts to move relative to each other. This allows the positional relationship between the positioning parts and locking parts to be changed, enabling the locking part to be locked to a single positioning part, and thus allowing the regulated position to be set accurately.

[0011] Furthermore, in the adjustment device, the plurality of positioning parts and the locking parts can be relatively changed between a locking position in which the locking part locks one of the positioning parts in the axial direction and a release position in which the locking part is released from one of the positioning parts. The locking position and the release position of one of the positioning parts and the locking part can be switched by the plunger-side member and the barrel-side member moving relatively in the circumferential direction around the axial direction or in a direction perpendicular to the axial direction.

[0012] With this configuration, the plunger-side member and the barrel-side member move relative to each other in the circumferential direction around the axial direction, thereby switching between locking and unlocking the positioning part and the locking part. This allows the locking and unlocking of the positioning part and the locking part to be switched in a circumferential direction different from the axial direction, which is the direction of movement of the plunger for ejecting the contents. Therefore, it is possible to prevent accidentally releasing the locking of the positioning part and the locking part while the plunger is moving in the axial direction.

[0013] Furthermore, in the adjustment device, the plurality of positioning parts and the locking parts can be relatively changed between a locking position in which the locking part locks to one of the positioning parts in the axial direction and a release position in which the locking part is released from locking to one of the positioning parts. When the plurality of positioning parts and the locking parts are in the release position, the plunger-side member and the barrel-side member may move relatively in the axial direction, thereby causing the plurality of positioning parts and the locking parts to move relatively in the axial direction.

[0014] With this configuration, the relative axial movement between the plunger-side member and the barrel-side member causes multiple positioning parts and locking parts to move relative to each other in the axial direction. Therefore, by moving the plunger-side member and the barrel-side member relative to each other in the axial direction at the release position, the axial positional relationship between the positioning parts and locking parts can be changed, allowing the locking parts to be locked to a single positioning part, and thus enabling accurate setting of the regulating position.

[0015] Furthermore, in the adjustment device, the positioning part located at the furthest forward or base end in the axial direction among the plurality of positioning parts is the maximum positioning part, which is the adjusted discharge amount for the amount of contents contained in the barrel. The position setting mechanism may be configured such that the locking part and the positioning part are relatively movable, after restricting the movement of the plunger in the axial direction by the plunger restricting part located at a restricted position where the locking part is locked to the maximum positioning part, the locking part is locked to a positioning part other than the maximum positioning part.

[0016] With this configuration, the plunger restricting part, located in a restricted position with the locking part engaged with the maximum positioning part, restricts the axial movement of the plunger, and then the locking part is able to engage with another positioning part. Thus, when there is excess material inside the barrel, the plunger restricting part in the restricted position with the locking part engaged with the maximum positioning part restricts the axial movement of the plunger, thereby discharging the excess material and leaving the adjustable maximum discharge amount inside the barrel. Furthermore, by engaging the locking part with another positioning part, the desired discharge amount can be precisely adjusted.

[0017] The syringe of the present invention comprises a syringe body including a barrel capable of containing a substance, the barrel having a tip portion positioned on the axial end side for discharging the substance and a base portion positioned on the axial base end side for discharging the substance and having an opening that communicates with the interior, and a plunger inserted into the barrel from the opening and moving toward the axial end side to discharge the substance from the tip portion, and the adjustment device.

[0018] With this configuration, the locking portion is movable relative to multiple positioning portions arranged in the axial direction. When the locking portion is positioned by locking it axially to each positioning portion through this relative movement, the regulated position of the plunger regulating portion is set. In the position setting mechanism, the regulated position of the plunger regulating portion is set by moving the positioning portion and the locking portion relative to each other and locking the locking portion to one positioning portion. Therefore, the regulated position can be accurately set to adjust the discharge amount and a desired amount of contents can be discharged. [Effects of the Invention]

[0019] Based on the above, the present invention provides an adjustment device and a syringe that can reliably adjust and dispense the amount of contents contained in the syringe. [Brief explanation of the drawing]

[0020] [Figure 1] Figure 1 is a front view of the syringe according to this embodiment in its initial state. [Figure 2] Figure 2 is a longitudinal sectional view of the syringe. [Figure 3] Figure 3 is an exploded perspective view of the syringe. [Figure 4] Figure 4 is a front view of the syringe with the plunger side member pulled out to determine the maximum discharge amount. [Figure 5] Figure 13 is a front view of the syringe with the maximum positioning portion and the locking portion in the locked position. [Figure 6] Figure 6 is a front view of the syringe when the discharge of the excess amount of the chemical solution is completed. [Figure 7] Figure 7 is a front view of the syringe with the maximum positioning portion and the locking portion in the unlocking position. [Figure 8] Figure 8 is a front view of the syringe with the plunger side member pushed in. [Figure 9] Figure 9 is a front view of the syringe with the positioning portion and the locking portion in the locked position. [Figure 10] Figure 10 is a front view of the syringe when the discharge of the desired amount of the chemical solution is completed. [Figure 11] Figure 11 is a front view of the syringe according to a modified example in its initial state. [Figure 12] Figure 12 is a longitudinal sectional view of the syringe. [Figure 13] Figure 13 is an exploded perspective view of the syringe. [Figure 14] Figure 14 is a front view of the syringe with the plunger side member pulled out to determine the maximum discharge amount. [Figure 15] Figure 15 is a front view of the syringe with the maximum positioning portion and the locking portion in the locked position. [Figure 16] Figure 16 is a front view of the syringe when the discharge of the excess amount of the chemical solution is completed. [Figure 17] Figure 17 is a front view of the syringe with the maximum positioning portion and the locking portion in the unlocking position. [Figure 18] Figure 18 is a front view of the syringe with the plunger-side member pushed in. [Figure 19] Figure 19 is a front view of the syringe with the positioning and locking parts in the locked position. [Figure 20] Figure 20 is a front view of the syringe after the desired amount of drug solution has been dispensed. [Figure 21] Figure 21 is a front view of the syringe in its initial state according to a modified example. [Figure 22] Figure 22 is a side view of the syringe in its initial state. [Figure 23] Figure 23 is a front view of the syringe in its initial state according to a modified example. [Figure 24] Figure 24 is a longitudinal cross-sectional view of the syringe in its initial state. [Figure 25] Figure 25 is a front view of the syringe in its initial state according to a modified example. [Figure 26] Figure 26 is a perspective view of the main parts of the syringe in its initial state. [Figure 27] Figure 27 is a cross-sectional view of the main part of the syringe, where Figure 27(a) shows the locked position of the positioning part and the locking part, and Figure 27(b) shows the released position of the positioning part and the locking part. [Figure 28] Figure 28 is a perspective view showing a conventional syringe. [Modes for carrying out the invention]

[0021] Hereinafter, a syringe according to an embodiment of the present invention will be described with reference to Figures 1 to 10.

[0022] Syringe 1 is a syringe for dispensing a desired amount of a liquid drug or other substance. Specifically, Syringe 1 is a syringe that dispenses 1.0 ml of liquid drug in amounts adjusted in 0.1 ml increments. That is, the maximum adjustable dispensing volume of Syringe 1 is 1.0 ml. However, the maximum dispensing volume of Syringe 1 may be other than 1.0 ml, such as 2.0 ml or 2.25 ml. Furthermore, the adjustable dispensing volume unit of Syringe 1 may be other than 0.1 ml.

[0023] As shown in Figure 1, the syringe 1 is roughly cylindrical in shape. The syringe 1 also comprises a syringe body 2 and an adjustment device 3.

[0024] As shown in Figure 2, the syringe body 2 comprises a barrel 4 including a tip portion 40 positioned on the axial end side for discharging the contents, and a base portion 41 positioned on the axial base end side with an opening 410 that communicates with the inside, and a plunger 5 inserted into the barrel 4 from the opening 410 and moving toward the axial end side to discharge the contents such as a drug solution from the tip portion 40.

[0025] The adjustment device 3 is configured to adjust the discharge amount in the syringe body 2. In this embodiment, the adjustment device 3 comprises a plunger-side member 6 and a barrel-side member 7.

[0026] In syringe 1, the side where the tip 40 of the barrel 4 is located (the lower side in Figure 1) is referred to as the "tip side," and the side where the base end 41 of the barrel 4 is located (the upper side in Figure 1) is referred to as the "base end side." Furthermore, the "axial direction" of syringe 1 is the direction of the cylinder axis of syringe 1. In addition, the radial direction of syringe 1 is also simply referred to as the "radial direction."

[0027] When using syringe 1, first pull the plunger 5 towards the base end to draw the drug solution into the barrel 4 (Figure 1), then pull the plunger-side member 6 towards the base end (Figure 4), rotate the plunger-side member 6 in the circumferential direction around the axial direction to determine the maximum discharge amount (Figure 5), and then push the plunger 5 towards the tip to discharge the excess amount of drug solution relative to the maximum discharge amount (Figure 6). Next, rotate the plunger-side member 6 in the opposite direction in the circumferential direction around the axial direction (Figure 7), push the plunger-side member 6 towards the tip (Figure 8), rotate the plunger-side member 6 in the circumferential direction around the axial direction to determine the desired discharge amount (Figure 9), and then push the plunger 5 towards the tip to discharge the desired amount of drug solution (Figure 10). Note that the circumferential direction around the axial direction is also simply referred to as the "circumferential direction".

[0028] The following describes the components of the syringe body 2 and the adjustment device 3.

[0029] As shown in Figure 3, the barrel 4 is a cylindrical body that contains a liquid medicine or other substance inside. In addition to the tip portion 40 and the base portion 41, the barrel 4 also has a cylindrical connecting portion 42 that connects the tip portion 40 and the base portion 41. In this embodiment, a needle N is attached to the tip portion 40 of the barrel 4.

[0030] The outer diameter of the tip portion 40 is smaller than the outer diameter of the connecting portion 42. The outer diameter of the connecting portion 42 is approximately the same at all points along the axial direction of the cylinder.

[0031] The base portion 41 includes a flange 411 that extends radially outward from the entire outer circumference of one end of the connecting portion 42 in the direction of the cylindrical axis. The base portion 41 is an annular plate when viewed from the direction of the cylindrical axis, for example, an annular plate. The end face of the flange 411 on the tip side is flat.

[0032] Barrel 4 is formed from a material that is transparent and can withstand the internal pressure applied when dispensing the drug solution. Specifically, the material of barrel 4 is a resin containing cyclic olefins such as norbornene as repeating units, or glass. More specifically, the material of barrel 4 is a transparent resin such as COP (cycloolefin polymer), which is a homopolymer of cyclic olefins, or COC (cycloolefin copolymer), which is a copolymer of cyclic olefins and ethylene, or glass.

[0033] The plunger 5 is a component that can be pushed into the barrel 4 from its base end 41 towards its tip end 40. The plunger 5 also comprises a rod 50, which is the shaft, and a piston 51 provided at the tip of the rod 50.

[0034] The rod 50 is a shaft that moves when discharging the liquid chemical from the barrel 4. The rod 50 also comprises a shaft portion 52 and a disc-shaped operating portion 53 provided on the base end side of the shaft portion 52. The material of the rod 50 is a resin such as PC (polycarbonate), ABS (acrylonitrile butadiene styrene), PP (polypropylene), PE (polyethylene), COP (cycloolefin polymer), COC (cycloolefin copolymer), PS (polystyrene), AS (acrylonitrile styrene), PET (polyethylene terephthalate), PBT (polybutylene), POM (polyacetal), or TPX (polymethylpentene).

[0035] The base half of the shaft portion 52 is cylindrical. The tip half of the shaft portion 52 is axial with a cross-shaped cross-section. The shaft portion 52 only needs to be axial; it may have a cross-shaped cross-section overall, or it may be cylindrical or a columnar shape with a polygonal cross-section.

[0036] The operating section 53 is a disc-shaped flange with a diameter larger than the diameter of the shaft section 52. The operating section 53 is also provided continuously with the shaft section 52. In this embodiment, the end face of the operating section 53 at the tip is flat. The operating section 53 may also be elliptical or polygonal.

[0037] The piston 51 is a component that can abut against the inner surface located on the base end side of the tip portion 40 of the barrel 4. The piston 51 also makes close contact with the entire inner circumference of the connecting portion 42 of the barrel 4.

[0038] The adjustment device 3 includes a plunger restricting section 30 that restricts the axial movement of the plunger 5 toward the tip, and a position setting mechanism 31 that sets the restricting position of the plunger restricting section 30. The position setting mechanism 31 comprises a plurality of positioning sections 32 arranged to have different axial positions, and a locking section 33 that can be locked in the axial direction to each positioning section 32.

[0039] In this embodiment, the plunger regulating portion 30 is part of the plunger-side member 6. Also, the positioning portion 32 is part of the barrel-side member 7, and the locking portion 33 is part of the plunger-side member 6.

[0040] The plunger-side member 6 is approximately cylindrical. The plunger-side member 6 is attached to the syringe body 2, surrounding the plunger 5 from the outer diameter (Figure 2). Furthermore, the plunger-side member 6 is inserted into the barrel-side member 7 and is surrounded from the outer diameter by the barrel-side member 7. The material of the plunger-side member 6 is a resin such as PC (polycarbonate), ABS (acrylonitrile butadiene styrene), PP (polypropylene), PE (polyethylene), COP (cycloolefin polymer), COC (cycloolefin copolymer), PS (polystyrene), AS (acrylonitrile styrene), PET (polyethylene terephthalate), PBT (polybutylene), POM (polyacetal), or TPX (polymethylpentene).

[0041] In this embodiment, the plunger-side member 6 has a plunger restricting portion 30 that abuts against the plunger 5 in the axial direction, thereby restricting the axial movement of the plunger 5 toward the tip (Figure 1). The plunger-side member 6 also has a plunger-side main body portion 61 on which a locking portion 33 is formed.

[0042] The plunger restricting portion 30 abuts the plunger reference portion 54 of the plunger 5, specifically the operating portion 53 of the plunger 5, in the axial direction. The end face on the base end side of the plunger restricting portion 30 is the surface that receives the plunger reference portion 54, specifically the operating portion 53 of the plunger 5. The plunger restricting portion 30 can be a plate shape with a flat end face on the base end side, and specifically a substantially rectangular plate shape with a through hole in the center. More specifically, the plunger restricting portion 30 is a plate shape with a through hole in the center, where one of the four sides constituting the outer circumference is straight and the other opposing side is curved and bulges radially outward. In this embodiment, the outer circumference of the plunger restricting portion 30 is located radially outward from the outer diameter of the barrel-side main body portion 71 of the barrel-side member 7.

[0043] The plunger-side main body portion 61 is cylindrical, specifically a cylindrical shape. Furthermore, the plunger-side main body portion 61 extends from the plunger restricting portion 30 toward the tip. The outer peripheral edge of the plunger-side main body portion 61 is located inward in diameter than the outer peripheral edge of the plunger restricting portion 30. In this embodiment, a locking portion 33 is formed at the tip of the plunger-side main body portion 61 (Figure 3). Specifically, a pair of locking portions 33 are formed at the tip of the plunger-side main body portion 61, flanking the cylindrical shaft. Note that one locking portion 33 may be formed on the plunger-side main body portion 61, or three or more may be formed flanking the cylindrical shaft.

[0044] The locking portion 33 is a protrusion that projects radially outward from the outer circumferential surface of the plunger-side main body portion 61. The locking portion 33 is an elongated protrusion, and its longitudinal direction is aligned with the circumferential direction of the plunger-side main body portion 61. In this embodiment, the pair of locking portions 33 are positioned at equal intervals in the circumferential direction of the plunger-side main body portion 61. More specifically, the locking portions 33 are positioned 180° apart in the circumferential direction of the plunger-side main body portion 61. Furthermore, the end of the locking portion 33 located closer to the positioning portion 32 has a tapered shape, with the dimension in the short direction becoming smaller as it approaches the positioning portion 32.

[0045] The axial end faces of the locking portion 33 are contact surfaces 330 and 331 that abut against the positioning portion 32 in the axial direction. Both contact surfaces 330 and 331 are planes perpendicular to the axial direction.

[0046] The locking portion 33 may be an elongated protrusion whose longitudinal direction is aligned with the cylindrical axis direction of the plunger-side main body portion 61. Furthermore, the locking portion 33 may be a circular protrusion, a square protrusion, or a polygonal protrusion in plan view.

[0047] The barrel-side member 7 is substantially cylindrical. The barrel-side member 7 is attached to the syringe body 2 by being fixed to the barrel 4. Specifically, the barrel-side member 7 is fixed to the base end portion 41 of the barrel 4. In this embodiment, the barrel-side member 7 has a barrel contact portion 70 that abuts the barrel 4 in the axial direction. In addition to the barrel contact portion 70, the barrel-side member 7 also has a barrel-side body portion 71. The material of the barrel-side member 7 is a resin such as PC (polycarbonate), ABS (acrylonitrile butadiene styrene), PP (polypropylene), PE (polyethylene), COP (cycloolefin polymer), COC (cycloolefin copolymer), PS (polystyrene), AS (acrylonitrile styrene), PET (polyethylene terephthalate), PBT (polybutylene), POM (polyacetal), or TPX (polymethylpentene).

[0048] The barrel contact portion 70 constitutes the tip of the barrel-side member 7. The barrel contact portion 70 also contacts the barrel reference portion 43, which adjusts the discharge amount in the barrel 4, specifically the flange 411 of the barrel 4, in the axial direction. By contacting the barrel 4 in the axial direction, the barrel contact portion 70 restricts the movement of the barrel-side member 7 itself toward the tip in the axial direction relative to the barrel 4.

[0049] In this embodiment, the barrel contact portion 70 is fitted onto the base end portion 41 of the barrel 4 (Figure 2). The barrel contact portion 70 also includes a base end contact portion 700 that covers the base end portion 41 of the barrel 4 from the base end side, a tip end contact portion 701 that covers the base end portion 41 of the barrel 4 from the tip side, and a connecting portion 702 that connects the base end contact portion 700 and the tip end contact portion 701.

[0050] Both the base contact portion 700 and the tip contact portion 701 are plate-shaped and have a through hole in the center. The plunger 5 can be inserted through the through hole in the base contact portion 700 and the tip contact portion 701.

[0051] The connecting portion 702 is at least a side wall connecting the outer periphery of the base end contact portion 700 and the outer periphery of the tip contact portion 701. In this embodiment, the connecting portion 702 includes a first connecting portion 702A that connects the outer periphery of the base end contact portion 700 and the outer periphery of the tip contact portion 701, and a second connecting portion 702B that connects the base end contact portion 700 and the tip contact portion 701, located radially inward from the first connecting portion 702A. That is, the connecting portion 702 has a two-layer structure arranged radially.

[0052] The barrel-side main body portion 71 is substantially cylindrical. The outer diameter of the barrel-side main body portion 71 is uniform. The inner diameter of the barrel-side main body portion 71 is also uniform. Furthermore, the barrel-side main body portion 71 extends from the base end contact portion 700 of the barrel contact portion 70 toward the base end. In this embodiment, the barrel-side main body portion 71 is formed integrally with the barrel contact portion 70.

[0053] The outer circumferential surface of the barrel-side main body portion 71 is continuous with the outer circumferential surface of the barrel contact portion 70. The outer diameter of the barrel-side main body portion 71 is smaller than the outer diameter of the barrel contact portion 70.

[0054] The barrel-side main body portion 71 has a through-hole, which is a position adjustment portion 34, that penetrates the barrel-side main body portion 71 in the thickness direction (Figure 1). Specifically, a pair of position adjustment portions 34 are formed in the barrel-side main body portion 71, flanking the cylindrical shaft. Note that the position adjustment portion 34 may be formed as one in the barrel-side main body portion 71, or as three or more flanking the cylindrical shaft.

[0055] In this embodiment, the position adjustment units 34 are arranged at equally spaced positions in the circumferential direction. Specifically, the position adjustment units 34 are arranged at positions 180° away from the plunger-side main body 61 in the circumferential direction.

[0056] The position adjustment unit 34 has a plurality of positioning units 32. Specifically, the position adjustment unit 34 has 11 positioning units 32 and a passage unit 35 that communicates with these positioning units 32. Note that the number of positioning units 32 is not limited to 11; it can be two or more.

[0057] The positioning portion 32 is a through-hole that penetrates the barrel-side main body portion 71 in the thickness direction. The positioning portion 32 is an elongated through-hole, and its longitudinal direction is aligned with the circumferential direction of the barrel-side main body portion 71. Furthermore, one side of the positioning portion 32 in the circumferential direction is open. The other end of the positioning portion 32 in the circumferential direction is tapered. In this embodiment, the positioning portions 32, which are aligned in the axial direction, are arranged in the barrel-side main body portion 71 at equal intervals in the axial direction.

[0058] The pair of surfaces that define the axial edge of the positioning portion 32 are the contact surfaces 320 and 321 that come into contact with the locking portion 33 in the axial direction. Both the contact surfaces 320 and 321 are planes perpendicular to the axial direction.

[0059] The passage portion 35 is a through-hole that penetrates the barrel-side main body portion 71 in the thickness direction. Furthermore, the passage portion 35 is a passage that allows the locking portion 33 to be moved relative to the positioning portion 32 by communicating with a plurality of positioning portions 32 in order to change the correspondence between the positioning portion 32 and the locking portion 33. The passage portion 35 is an elongated through-hole, and its longitudinal direction is aligned with the axial direction. In this embodiment, the passage portion 35 communicates with one end edge in the circumferential direction of each of the positioning portions 32 that are aligned in the axial direction, thereby forming a single through-hole together with these positioning portions 32. In addition, the passage portion 35 extends from the tip edge of the barrel-side main body portion 71, beyond the positioning portion 32A located at the base end, to a position on the base end side. The width of the passage portion 35, that is, the dimension of the passage portion 35 in the short direction, is uniform.

[0060] In this embodiment, a slit 710 extending in the axial direction is provided at the base end of the barrel-side main body portion 71. The slit 710 includes a first slit 711 located at a position aligned with the positioning portion 32 on the axial base end side. The slit 710 also includes a second slit 712 that, together with the first slit 711, sandwiches the passage portion 35 in the circumferential direction. When the plunger-side member 6 is inserted into the barrel-side member 7, that is, when the barrel-side member 7 and the plunger-side member 6 are combined, the locking portion 33 formed on the plunger-side member 6 enters the barrel-side member 7 from the base end side and enters the position adjustment portion 34, specifically the passage portion 35. At this time, the portion of the barrel-side main body portion 71 located between the first slit 711 and the second slit 712 flexes radially outward, making it easier for the locking portion 33 to enter the barrel-side member 7.

[0061] In this adjustment device 3, the multiple positioning parts 32 and locking parts 33 are configured to be relatively movable, forming a position setting mechanism 31 (Figure 1). Furthermore, when the multiple positioning parts 32 and locking parts 33 move relative to one of the positioning parts 32 and the locking part 33 locks onto and positions the plunger restricting part 30, the restricting position of the plunger restricting part 30 is set. In this way, when the locking part 33 locks onto and positions one of the multiple positioning parts 32 selected from among the multiple positioning parts 32, the restricting position of the plunger restricting part 30 is set, and the movement of the plunger 5 toward the tip side is restricted by the plunger restricting part 30 with the restricted position set.

[0062] Furthermore, in this adjustment device 3, the plunger-side member 6 is not fixed to the barrel 4, while the barrel-side member 7 is fixed to the barrel 4 as described above. Therefore, with the plunger-side member 6 and the barrel-side member 7 attached to the syringe body 2, the plunger-side member 6 moves relative to the barrel-side member 7 which is fixed to the barrel 4, causing the multiple positioning parts 32 and locking parts 33 to move relative to each other.

[0063] Furthermore, in this adjustment device 3, the plunger-side member 6 and the barrel-side member 7 move relative to each other in the circumferential direction. That is, the plunger-side member 6 and the barrel-side member 7 rotate relative to each other in the circumferential direction. In this embodiment, with the plunger-side member 6 and the barrel-side member 7 attached to the syringe body 2, the plunger-side member 6 rotates circumferentially with respect to the barrel-side member 7 fixed to the barrel 4, causing the multiple positioning parts 32 and locking parts 33 to move relative to each other in the circumferential direction. Also, this relative movement allows the multiple positioning parts 32 and locking parts 33 to be able to change their relative positions between a locked position in which the locking part 33 is axially locked to one positioning part 32 and a released position in which the locking part 33 is released from locking to one positioning part 32. That is, the relative rotation of the plunger-side member 6 and the barrel-side member 7 in the circumferential direction switches between the locked position and the released position of one positioning part 32 and locking part 33.

[0064] Furthermore, in this adjustment device 3, with the multiple positioning parts 32 and locking parts 33 in the released position, the plunger-side member 6 and the barrel-side member 7 move relative to each other in the axial direction, causing the multiple positioning parts 32 and locking parts 33 to move relative to each other in the axial direction. In this embodiment, with the multiple positioning parts 32 and locking parts 33 in the released position, the plunger-side member 6 moves axially with respect to the barrel-side member 7 fixed to the barrel 4. As a result, the locking parts 33 move axially with respect to the multiple positioning parts 32 formed on the barrel-side member 7 fixed to the barrel 4, that is, the multiple positioning parts 32 whose position relative to the barrel 4 is fixed.

[0065] In this embodiment, the positioning unit 32 located furthest to the base end in the axial direction among the multiple positioning units 32 is the maximum positioning unit 32A, which determines the maximum discharge amount as the adjusted discharge amount for the amount of contents contained in the barrel 4.

[0066] Furthermore, the position setting mechanism 31 is configured such that the locking portion 33 and the positioning portion 32 are relatively movable, after restricting the axial movement of the plunger 5 with a plunger restricting portion 30 located at a restricted position where the locking portion 33 is locked to the maximum positioning portion 32A, the locking portion 33 is locked to a positioning portion 32 other than the maximum positioning portion 32A. In this embodiment, the position setting mechanism 31 is configured such that the locking portion 33 and the positioning portion 32 are relatively movable, after restricting the movement of the plunger 5 toward the tip side with a plunger restricting portion 30 located at a restricted position where the locking portion 33 is locked to the maximum positioning portion 32A, the locking portion 33 is locked to a positioning portion 32 located further toward the tip than the maximum positioning portion 32A.

[0067] The following describes in detail how to use syringe 1. First, the syringe is set to its initial state with the liquid drug contained in the barrel 4 (Figure 1). Specifically, the user of syringe 1 inserts the needle N attached to syringe 1 into a vial or the like containing the liquid drug and pulls the plunger 5 towards the proximal end. This draws the liquid drug into the barrel 4, setting syringe 1 to its initial state. In the initial state, the locking part 33 is in the released position, having released its lock from one of the positioning parts 32. When the positioning part 32 and the locking part 33 are in the released position, the locking part 33 is located within the passage part 35 that extends in the axial direction, and the axial movement of the locking part 33 within the passage part 35 is not restricted.

[0068] Next, after pulling the plunger-side member 6 towards the base end (Figure 4), the plunger-side member 6 and the barrel-side member 7 are rotated relative to each other in the circumferential direction to determine the maximum discharge volume of the syringe 1 (Figure 5).

[0069] Specifically, with the locking portion 33 in the released position, that is, with the locking portion 33 in a position where it has been released from one positioning portion 32, that is, with the locking portion 33 able to move axially within the passage portion 35, the plunger-side member 6 is pulled up towards the base end from the initial state so that the locking portion 33 is adjacent to the maximum positioning portion 32A in the circumferential direction (Figure 4). In this state, there is an axial gap between the operating portion 53 of the plunger 5 and the plunger regulating portion 30 of the plunger-side member 6. The axial dimension of this gap corresponds to the excess amount of liquid drug contained in the barrel 4 relative to the maximum discharge volume of the syringe 1. The maximum discharge volume is the maximum amount of liquid drug discharged from the syringe 1.

[0070] Furthermore, by rotating the plunger-side member 6 and the barrel-side member 7 relative to each other in the circumferential direction, the maximum discharge volume of the syringe 1 is determined by setting the locking position in which the locking portion 33 is axially locked to the maximum positioning portion 32A (Figure 5). That is, the maximum discharge volume of the syringe 1 is determined by locking the axial movement of the plunger regulating portion 30 with the maximum positioning portion 32A and the locking portion 33 as the locking position. In this embodiment, when switching the maximum positioning portion 32A and the locking portion 33 from the released position to the locked position, the plunger-side member 6 is moved clockwise relative to the barrel-side member 7.

[0071] When the maximum positioning portion 32A and the locking portion 33 are in the locked position, the contact surfaces 330 and 331 of the locking portion 33 come into contact with the contact surfaces 320 and 321 of the maximum positioning portion 32A, thereby locking the locking portion 33 to the maximum positioning portion 32A in the axial direction. In this embodiment, the contact surface 330 on the base end side of the locking portion 33 comes into contact with the contact surface 320 on the base end side of the maximum positioning portion 32A, thereby restricting the movement of the locking portion 33 toward the base end. Furthermore, the contact surface 331 on the tip side of the locking portion 33 comes into contact with the contact surface 321 on the tip side of the maximum positioning portion 32A, thereby restricting the movement of the locking portion 33 toward the tip. As a result, the axial movement of the plunger-side member 6 on which the locking portion 33 is formed is restricted.

[0072] Subsequently, the plunger 5 is pushed toward the tip until the operating part 53 of the plunger 5 contacts the plunger restricting part 30 of the plunger side member 6 in the axial direction, thereby discharging the excess amount of liquid chemical relative to the maximum discharge amount (Figure 6).

[0073] During the pushing of the plunger 5 toward the tip, the axial movement of the plunger-side member 6 relative to the barrel-side member 7 on which the maximum positioning portion 32A is formed is restricted. As a result, the axial movement of the plunger restricting portion 30, which restricts the axial movement of the plunger 5, relative to the barrel 4 is fixed. Therefore, during the pushing of the plunger 5 toward the tip, the axial movement of the plunger 5 is restricted by the plunger restricting portion 30, which is located in a restricted position with the locking portion 33 engaged with the maximum positioning portion 32A.

[0074] Furthermore, immediately after the excess amount of liquid is discharged, the plunger-side member 6 and the barrel-side member 7 are rotated relative to each other in the circumferential direction (Figure 7), the plunger-side member 6 is pushed towards the tip (Figure 8), and then the plunger-side member 6 and the barrel-side member 7 are rotated relative to each other in the circumferential direction to adjust and determine the desired discharge amount (Figure 9).

[0075] Specifically, from the state immediately after the discharge of excess liquid, the plunger-side member 6 and the barrel-side member 7 are rotated relative to each other in the circumferential direction, thereby setting the locking portion 33 to a released position in which it is released from one of the positioning portions 32 (Figure 7). That is, the positioning portion 32 and the locking portion 33 are set to the released position, more specifically, the locking portion 33 is moved from within the maximum positioning portion 32A into the passage portion 35, unlocking the axial movement of the plunger-side member 6 and allowing the plunger-side member 6 to move relative to the barrel-side member 7 in the axial direction. In this embodiment, when switching the maximum positioning portion 32A and the locking portion 33 from the locked position to the released position, the plunger-side member 6 is moved counterclockwise relative to the barrel-side member 7.

[0076] Next, the syringe 1 is set to the desired discharge volume (Figure 8). Specifically, the plunger-side member 6 is pushed towards the tip so that the locking portion 33 is adjacent to the desired positioning portion 32B in the circumferential direction. That is, the user selects a positioning portion 32B suitable for the desired discharge volume and pushes the plunger-side member 6 towards the tip until the selected positioning portion 32B and the locking portion 33 are adjacent in the circumferential direction. In this state, the locking portion 33 remains in the released position, having been released from locking to one positioning portion 32.

[0077] Furthermore, by rotating the plunger-side member 6 and the barrel-side member 7 relative to each other in the circumferential direction, the locking portion 33 is set to a locking position that axially locks it to the selected positioning portion 32B, thereby determining the desired discharge amount of the syringe 1 (Figure 9). In this embodiment, when switching the positioning portion 32B and the locking portion 33 from the released position to the locked position, the plunger-side member 6 is moved clockwise relative to the barrel-side member 7. Also, the contact surfaces 330 and 331 of the locking portion 33 come into contact with the contact surfaces 320 and 321 of the positioning portion 32B, thereby locking the locking portion 33 to the positioning portion 32B in the axial direction. That is, by setting the positioning portion 32B and the locking portion 33 to the locked position and locking the axial movement of the plunger regulating portion 30, the discharge amount of the syringe 1 is determined.

[0078] When the positioning portion 32B and the locking portion 33 are in the locked position, the contact surfaces 330 and 331 of the locking portion 33 come into contact with the contact surfaces 320 and 321 of the positioning portion 32B, thereby locking the locking portion 33 to the positioning portion 32B in the axial direction. In this embodiment, the contact surface 330 on the base end side of the locking portion 33 comes into contact with the contact surface 320 on the base end side of the positioning portion 32B, thereby restricting the movement of the locking portion 33 toward the base end. Furthermore, the contact surface 331 on the tip end side of the locking portion 33 comes into contact with the contact surface 321 on the tip end side of the positioning portion 32B, thereby restricting the movement of the locking portion 33 toward the tip end. As a result, the axial movement of the plunger-side member 6 on which the locking portion 33 is formed is restricted.

[0079] Subsequently, the operating section 53 of the plunger 5 pushes the plunger 5 toward the tip until it contacts the plunger restricting section 30 of the plunger-side member 6 in the axial direction, thereby discharging a desired amount of liquid (Figure 10). This discharge amount is determined by the axial dimension from the maximum positioning section 32A to the selected positioning section 32B.

[0080] During the pushing of the plunger 5 toward its tip, the axial movement of the plunger-side member 6 relative to the barrel-side member 7 on which the positioning portion 32B is formed is restricted. As a result, the axial movement of the plunger restricting portion 30, which restricts the axial movement of the operating portion 53 of the plunger 5, relative to the barrel 4 is fixed. Therefore, during the pushing of the plunger 5 toward its tip, the axial movement of the plunger 5 is restricted by the plunger restricting portion 30, which is located in a restricted position with the locking portion 33 engaged with the positioning portion 32B.

[0081] In the syringe 1 described above, a locking part 33, which is relatively movable relative to multiple positioning parts 32, is positioned by locking it axially to each positioning part 32, thereby setting the restricting position of the plunger restricting part 30. Therefore, in the position setting mechanism 31, the positioning part 32 and the locking part 33 are moved relative to each other, and the locking part 33 is locked to one positioning part 32, thereby setting the restricting position of the plunger restricting part 30. In other words, the user selects a positioning part 32B suitable for the desired discharge amount, and locks the locking part 33 to the selected positioning part 32B, thereby setting the restricting position of the plunger restricting part 30. Thus, the adjustment device 3 accurately sets the restricting position of the plunger restricting part 30 and adjusts the discharge amount in the syringe 1, and the syringe 1 can discharge the desired amount of its contents. In other words, the syringe 1 can reliably adjust and discharge the amount of its contents.

[0082] In the above embodiment, the relative movement of the plunger-side member 6 and the barrel-side member 7 causes the multiple positioning parts 32 and locking parts 33 to move relative to each other. Therefore, by moving the plunger-side member 6 and the barrel-side member 7 relative to each other, the positional relationship between the positioning parts 32 and the locking parts 33 can be changed, allowing the locking part 33 to be locked to one positioning part 32, and the regulating position of the plunger regulating part 30 to be set accurately.

[0083] Furthermore, in the above embodiment, the positioning portion 32 and the locking portion 33 are switched between locked and unlocked by the relative movement of the plunger-side member 6 and the barrel-side member 7 in the circumferential direction. Therefore, the positioning portion 32 and the locking portion 33 can be switched between locked and unlocked by operating in the circumferential direction, which is different from the axial direction in which the plunger 5 moves to discharge the contents. Thus, it is possible to prevent accidentally releasing the locking of the positioning portion 32 and the locking portion 33 while the plunger 5 is moving in the axial direction.

[0084] Furthermore, in the above embodiment, the relative axial movement of the plunger-side member 6 and the barrel-side member 7 causes the multiple positioning parts 32 and locking parts 33 to move relative to each other in the axial direction. Therefore, by moving the plunger-side member 6 and the barrel-side member 7 relative to each other in the axial direction with the multiple positioning parts 32 and locking parts 33 in the released position, the axial positional relationship between the positioning parts 32 and locking parts 33 can be changed, allowing the locking part 33 to be locked to one positioning part 32, and thus the restricting position of the plunger restricting part 30 can be accurately set.

[0085] In the above embodiment, the plunger restricting unit 30, located in a restricted position with the locking unit 33 engaged with the maximum positioning unit 32A, restricts the axial movement of the plunger 5, and then the locking unit 33 and the positioning unit 32 are relatively movable so that the locking unit 33 engages with another positioning unit 32. Therefore, when there is excess material inside the barrel 4, the plunger restricting unit 30 in the restricted position with the locking unit 33 engaged with the maximum positioning unit 32A restricts the axial movement of the plunger 5, allowing the excess material to be discharged and leaving the adjustable maximum discharge amount inside the barrel 4. Then, by engaging the locking unit 33 with another positioning unit 32, the desired discharge amount can be precisely adjusted.

[0086] It should be noted that the syringe of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention. For example, the configuration of one embodiment can be added to the configuration of another embodiment, and a part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Furthermore, a part of the configuration of one embodiment can be deleted.

[0087] For example, the adjustment device 3 is not limited to the configuration of the above embodiment, and any configuration is acceptable in which one of the plunger-side member 6 and the barrel-side member 7 has a plurality of positioning parts 32, the other of the plunger-side member 6 and the barrel-side member 7 has a locking part 33, and when the plunger-side member 6 and the barrel-side member 7 are mounted on the syringe body 2, the plurality of positioning parts 32 and the locking part 33 move relative to each other as the plunger-side member 6 and the barrel-side member 7 move relative to each other.

[0088] Specifically, in the above embodiment, with the multiple positioning parts 32 and locking parts 33 in the released position, the plunger-side member 6 and the barrel-side member 7 move relative to each other in the axial direction, causing the locking parts 33 to move in the axial direction relative to the multiple positioning parts 32 whose positions relative to the barrel 4 are fixed. However, the multiple positioning parts 32 may move in the axial direction relative to the locking parts 33 whose positions relative to the barrel 4 are fixed. A syringe 1 with such a configuration will be described below with reference to Figures 11 to 18. This syringe 1 dispenses 2.25 ml of drug solution in amounts adjusted in 0.1 ml increments.

[0089] The components of the syringe body 2 are substantially the same as those shown in the above embodiment. In the barrel 4 of this embodiment, the outer edge of the base end portion 41 is substantially circular, and has a shape in which the circle is missing at two places on either side of the cylindrical shaft (Figure 13). In the plunger 5 of this embodiment, the base end half of the shaft portion 52 of the rod 50 is cylindrical.

[0090] The adjustment device 3 includes a plunger-side member 6 and a barrel-side member 7, as well as a grip 8. In this embodiment, the plunger regulating portion 30 of the adjustment device 3 is part of the plunger-side member 6. Furthermore, in the position setting mechanism 31 of the adjustment device 3, the positioning portion 32 is part of the plunger-side member 6, and the locking portion 33 is part of the barrel-side member 7.

[0091] The plunger-side member 6 is a roughly rectangular tube with rounded corners. The plunger-side member 6 also surrounds the barrel-side member 7 from the outer diameter. The plunger-side member 6 has a plunger-side main body portion 61 on which a positioning portion 32 is formed. Multiple protrusions 62 projecting outward in the outer circumferential surface of the plunger-side main body portion 61 are formed in the axial direction. The plunger-side member 6 also has a plunger restricting portion 30 that contacts the plunger 5 in the axial direction, thereby restricting the axial movement of the plunger 5 toward the tip.

[0092] The plunger restricting portion 30 abuts the plunger reference portion 54 of the plunger 5, specifically the operating portion 53 of the plunger 5, in the axial direction. The end face on the base end side of the plunger restricting portion 30 is the surface that receives the plunger reference portion 54, specifically the operating portion 53 of the plunger 5. More specifically, the plunger restricting portion 30 is a roughly rectangular plate shape with a through hole in the center and rounded corners. The outer edge of the plunger restricting portion 30 is continuous with the outer surface of the plunger-side main body portion 61 without any step difference.

[0093] The plunger-side main body portion 61 has a through-hole, which is a position adjustment portion 34, that penetrates the plunger-side main body portion 61 in the thickness direction. Specifically, a pair of position adjustment portions 34 are formed in the plunger-side main body portion 61, flanking the cylindrical shaft. Note that the position adjustment portion 34 may be formed as one in the plunger-side main body portion 61, or as three or more flanking the cylindrical shaft.

[0094] In this embodiment, the position adjustment units 34 are arranged at equally spaced positions in the circumferential direction of the plunger-side main body 61. More specifically, the position adjustment units 34 are arranged at positions 180° apart in the circumferential direction of the plunger-side main body 61.

[0095] The position adjustment unit 34 has a plurality of positioning units 32. Specifically, the position adjustment unit 34 has 23 positioning units 32 and a passage unit 35 that connects these positioning units 32.

[0096] The positioning portion 32 is a through-hole that penetrates the plunger-side main body portion 61 in the thickness direction. The positioning portion 32 is an elongated through-hole, and its longitudinal direction is aligned with the circumferential direction of the plunger-side main body portion 61. In this embodiment, the 23 locking portions 33, which are arranged at different axial positions, are positioned on the plunger-side main body portion 61 at equal intervals in the axial direction.

[0097] The passage portion 35 is a through-hole that penetrates the plunger-side main body portion 61 in the thickness direction. The passage portion 35 is also an elongated through-hole, and its longitudinal direction is aligned with the axial direction. In this embodiment, the passage portion 35 communicates with one circumferential edge of each of the 23 positioning portions 32, which are arranged at different axial positions, and together with these locking portions 33, forms a single through-hole. The passage portion 35 extends from a position adjacent to the positioning portion 32 located at the base end in the circumferential direction to a position further forward than the positioning portion 32 located at the tip end. The width of the passage portion 35, that is, the dimension of the passage portion 35 in the short direction, is uniform.

[0098] As described above, position adjustment parts 34 are arranged on each of the pair of main surfaces of the plunger-side main body 61 that sandwich the cylindrical shaft. Furthermore, protrusions 62 are arranged on each of the pair of main surfaces of the plunger-side main body 61 that sandwich the other cylindrical shaft, i.e., on the main surfaces where the position adjustment parts 34 are not arranged. In a vertical cross-sectional view, the protrusion 62 is defined by a horizontal surface 620 extending radially outward from the outer surface of the plunger-side main body 61, and a slope 621 extending from a position closer to the base end than where the horizontal surface 620 extends to the radially outward edge of the horizontal surface 620 (Figure 12).

[0099] In this embodiment, a slit 610 extending in the axial direction is provided at the tip of the plunger-side main body portion 61. The slit 610 includes a first slit 611 located at a position aligned with the positioning portion 32 on the axial tip side. The slit 610 also includes a second slit 612 that, together with the first slit 711, sandwiches the passage portion 35 in the circumferential direction.

[0100] The barrel-side member 7 is substantially cylindrical and is attached to the syringe body 2 by being fixed to the barrel 4 (Figure 12). Specifically, the barrel-side member 7 is fixed to the base end 41 of the barrel 4. The barrel-side member 7 is also fixed to the barrel 4 in a manner that surrounds the plunger 5 from the outer diameter. In this embodiment, the barrel-side member 7 has a barrel contact portion 70 that abuts the barrel 4 in the axial direction and a barrel-side body portion 71. The configuration of the barrel contact portion 70 is the same as that of the above embodiment, except that the connecting portion 702 has a single-layer structure.

[0101] The barrel-side body portion 71 is substantially cylindrical. The outer diameter of the barrel-side body portion 71 is uniform, and the inner diameter of the barrel-side body portion 71 is also uniform.

[0102] The outer circumferential surface of the barrel-side main body portion 71 is continuous with the outer circumferential surface of the barrel contact portion 70, and the outer circumferential surface of the barrel-side main body portion 71 is located inward in diameter than the outer circumferential surface of the barrel contact portion 70. Therefore, a step is formed at the boundary between the outer circumferential surface of the barrel-side main body portion 71 and the outer circumferential surface of the barrel contact portion 70.

[0103] In this embodiment, a locking portion 33 is formed at the base end of the barrel-side main body portion 71 (Figure 13). The locking portion 33 is a protrusion that projects radially outward from the outer circumferential surface of the barrel-side main body portion 71. The locking portion 33 is an elongated protrusion, and its longitudinal direction is aligned with the circumferential direction of the barrel-side main body portion 71. In this embodiment, a pair of locking portions 33 are arranged at equally spaced positions in the circumferential direction of the barrel-side main body portion 71. More specifically, the locking portions 33 are arranged at positions 180° apart in the circumferential direction of the barrel-side main body portion 71. The locking portion 33 may also be an elongated protrusion whose longitudinal direction is aligned with the cylindrical axis direction of the barrel-side main body portion 71. The locking portion 33 may be formed as one on the barrel-side main body portion 71, or as three or more on either side of the cylindrical axis.

[0104] In the adjustment device 3 of this embodiment, with the multiple positioning parts 32 and locking parts 33 in the released position, the plunger-side member 6 moves axially relative to the barrel-side member 7 fixed to the barrel 4, causing the multiple positioning parts 32 to move axially relative to the locking parts 33 formed on the barrel-side member 7 fixed to the barrel 4, i.e., the locking parts 33 that are fixed in position relative to the barrel 4 (Figure 11).

[0105] In this embodiment, the maximum positioning portion 32A is the positioning portion 32 located furthest forward in the axial direction among the 23 positioning portions 32. The position setting mechanism 31 is configured such that the locking portion 33 and the positioning portion 32 are relatively movable, after restricting the axial movement of the plunger 5 with a plunger restricting portion 30 located in a restricted position where the locking portion 33 is locked to the maximum positioning portion 32A, the locking portion 33 is locked to a positioning portion 32 located closer to the base end than the maximum positioning portion 32A.

[0106] The grip 8 is the part where the user places their fingers when pushing in the plunger 5. The grip 8 can also be used by the user to place their fingers when moving the plunger-side member 6 in the axial direction. The grip 8 is fitted onto the plunger-side main body portion 61 of the plunger-side member 6. In this embodiment, the grip 8 comprises a grip body portion 80 that covers the plunger-side main body portion 61, and a pair of grip extensions 81 that extend radially outward from two opposing locations on the grip body portion 80.

[0107] The grip body portion 80 is formed in an arc shape that surrounds the plunger-side body portion 61 (Figure 13). In addition, a pair of opposing claws 82 are formed on the tip of the inner circumferential surface of the grip body portion 80, projecting inward in diameter. The grip 8 is fixed to the plunger-side member 6 by the claws 82 engaging with the protrusions 62 on the outer circumferential surface of the plunger-side body portion 61 (Figure 12). The grip 8 can be repositioned toward the tip, but not toward the base. Specifically, when the grip 8 is pushed toward the tip, the claws 82 overcome the protrusions 62 of the plunger-side body portion 61, so the position of the grip 8 can be changed toward the tip. Also, when the grip 8 is pushed toward the base, the claws 82 catch on the protrusions 62 of the plunger-side body portion 61, so the grip 8 remains stationary.

[0108] Since the grip 8 moves together with the plunger-side member 6, its axial position relative to the barrel 4 can be changed towards the tip and base ends depending on the restricting position of the plunger restricting portion 30, which is part of the plunger-side member 6. In addition, by changing the fixed position of the grip 8 relative to the plunger-side member 6, its axial position relative to the plunger restricting portion 30 can be changed only towards the tip end.

[0109] The following describes in detail the operation of syringe 1. First, the plunger 5 is pulled up to the initial state in which the liquid medicine is contained in the barrel 4 (Figure 11). In the initial state, the locking part 33 is in the released position, released from locking to one of the positioning parts 32. When the positioning part 32 and the locking part 33 are in the released position, the locking part 33 is located within the passage part 35 that extends in the axial direction, and the axial movement of the locking part 33 within the passage part 35 is not restricted.

[0110] Next, with the locking portion 33 in the released position, that is, with the locking portion 33 still able to move axially within the passage portion 35, the plunger-side member 6 is pulled up from the initial position toward the base end so that the locking portion 33 is adjacent to the maximum positioning portion 32A in the circumferential direction (Figure 14). In this state, there is an axial gap between the operating portion 53 of the plunger 5 and the plunger restricting portion 30 of the plunger-side member 6.

[0111] Furthermore, by moving the plunger-side member 6 counterclockwise relative to the barrel-side member 7, the maximum positioning portion 32A and the locking portion 33 are switched from the released position to the locked position, thereby determining the maximum discharge volume of the syringe 1 (Figure 15). In other words, by setting the maximum positioning portion 32A and the locking portion 33 to the locked position and locking the axial movement of the plunger regulating portion 30, the maximum discharge volume of the syringe 1 is determined.

[0112] Subsequently, the operating part 53 of the plunger 5 pushes the plunger 5 toward the tip until it contacts the plunger restricting part 30 of the plunger side member 6 in the axial direction, thereby discharging an excess amount of liquid compared to the maximum discharge amount (Figure 16). During this pushing of the plunger 5 toward the tip, the axial movement of the plunger 5 is restricted by the plunger restricting part 30, which is located in a restricted position with the locking part 33 engaged with the maximum positioning part 32A.

[0113] Furthermore, immediately after the discharge of the excess liquid, the plunger-side member 6 is moved clockwise relative to the barrel-side member 7, thereby switching the maximum positioning portion 32A and the locking portion 33 from the locked position to the released position (Figure 17). That is, with the positioning portion 32 and the locking portion 33 in the released position, in this embodiment, the locking portion 33 is switched to a state in which it can move axially within the passage portion 35, unlocking the axial movement of the plunger-side member 6 and allowing the plunger-side member 6 to move relative to the barrel-side member 7 in the axial direction.

[0114] Next, the user selects a positioning section 32B suitable for the desired discharge volume and pushes the plunger-side member 6 toward the tip until the selected positioning section 32B and the locking section 33 are adjacent in the circumferential direction (Figure 18). In this state, the locking section 33 remains in the released position.

[0115] Furthermore, by moving the plunger-side member 6 counterclockwise relative to the barrel-side member 7, the selected positioning part 32B and locking part 33 are switched from the released position to the locked position (Figure 19). In other words, by setting the positioning part 32B and locking part 33 to the locked position and locking the axial movement of the plunger regulating part 30, the discharge amount of the syringe 1 is determined.

[0116] Subsequently, the operating part 53 of the plunger 5 pushes the plunger 5 toward the tip until it contacts the plunger restricting part 30 of the plunger-side member 6 in the axial direction, thereby discharging a desired amount of liquid (Figure 20). During this pushing of the plunger 5 toward the tip, the axial movement of the plunger-side member 6 relative to the barrel-side member 7 on which the selected positioning part 32B is formed is restricted. As a result, the axial movement of the plunger restricting part 30, which restricts the axial movement of the operating part 53 of the plunger 5, relative to the barrel 4 is fixed. Therefore, during this pushing of the plunger 5 toward the tip, the axial movement of the plunger 5 is restricted by the plunger restricting part 30, which is located in a restricted position with the locking part 33 engaged with the positioning part 32B.

[0117] Furthermore, as shown in Figures 21 and 22, the barrel-side member 7 may be equipped with a detachable grip 9. This syringe 1 is a syringe that dispenses 2.25 ml of drug solution in amounts adjusted in 0.1 ml increments, and is substantially the same as the syringe 1 shown in Figures 1 to 10.

[0118] The outer circumferential surface of the barrel-side main body portion 71 of the barrel-side member 7 has protrusions 72 that project radially outward. A pair of protrusions 72 are arranged at positions 180° apart in the circumferential direction of the barrel-side main body portion 71. In addition, two sets of pairs of protrusions 72 are arranged with an axial gap between them.

[0119] The detachable grip 9 comprises a grip body 90 that covers the barrel-side main body 71, and a pair of grip extensions 91 that extend outward from two opposing points on the grip body 90.

[0120] The grip body portion 90 is formed in an arc shape that surrounds the barrel-side body portion 71. In addition, a recess 92 that is recessed outward in the axial direction is formed in the axial center of the inner circumferential surface of the grip body portion 90. The recess 92 is continuous in the circumferential direction, but does not have to be continuous in the circumferential direction. In this embodiment, the detachable grip 9 can be attached to the tip or base end portion of the barrel-side body portion 71 by the recess 92 engaging with one of the pair of protrusions 72 on the outer circumferential surface of the barrel-side body portion 71.

[0121] Furthermore, as shown in Figures 23 and 24, the plunger-side member 6 and the barrel-side member 7 may be configured to be screwable. This syringe 1 is a syringe that dispenses 2.25 ml of drug solution in amounts adjusted in 0.1 ml increments, and the components of the syringe body 2 are substantially the same as those shown in the above embodiment.

[0122] The plunger regulating portion 30 of the adjustment device 3 is part of the plunger-side member 6. In addition, in the position setting mechanism 31 of the adjustment device 3, the positioning portion 32 is part of the plunger-side member 6, and the locking portion 33 is part of the barrel-side member 7.

[0123] The plunger-side member 6 comprises a plunger regulating portion 30 and a substantially cylindrical plunger-side main body portion 61. The outer circumferential surface of the plunger-side main body portion 61 is provided with screw threads 63. These screw threads 63 constitute the positioning portion 32 of the position setting mechanism 31.

[0124] Furthermore, the screw grooves on the outer circumferential surface of the plunger-side main body 61 are provided with two rows of protrusions 64, each consisting of multiple protrusions 64, spaced apart in the circumferential direction along the axial direction. The two rows of protrusions 64 are formed in pairs on the plunger-side main body 61, with the cylindrical shaft in between. In this embodiment, the two rows of protrusions 64 are arranged at equally spaced positions in the circumferential direction of the plunger-side main body 61. More specifically, the two rows of protrusions 64 are arranged at positions 180° apart in the circumferential direction of the plunger-side main body 61.

[0125] The barrel-side main body portion 71 is substantially cylindrical. A through hole 713 is provided at the base end of the barrel-side main body portion 71, penetrating in the thickness direction of the barrel-side main body portion 71 (Figure 23). The through hole 713 is substantially rectangular in shape. In this embodiment, a pair of through holes 713 are formed in the barrel-side main body portion 71, with the cylindrical shaft in between. Specifically, the through holes 713 are arranged at equally spaced positions in the circumferential direction of the barrel-side main body portion 71. More specifically, the through holes 713 are arranged at positions 180° apart in the circumferential direction of the barrel-side main body portion 71.

[0126] The barrel-side main body portion 71 has a piece portion 73 that extends into the through hole 713 from a part of the edge portion 714 that defines the through hole 713, specifically from one side 715 of the edge portion 714 that defines the through hole 713. The piece portion 73 is elastically deformable inward in diameter, that is, it can bend inward in diameter. A locking portion 33 is provided on the inner circumferential surface of the piece portion 73 as a convex portion that protrudes inward in diameter. The piece portion 73 is positioned at a distance of 180° in the circumferential direction of the barrel-side main body portion 71. Note that one piece portion 73 may be formed on the barrel-side main body portion 71, or three or more may be formed on either side of the cylindrical shaft. In this embodiment, the barrel-side main body portion 71 is formed as a separate part from the barrel contact portion 70.

[0127] In this syringe 1, the plunger-side member 6 rotates circumferentially relative to the barrel-side member 7 with the locking portion 33 of one side 73 of the barrel-side member 7 engaged in the screw groove of the plunger-side main body 61. During this rotation, the locking portion 33 can overcome the protrusion 64 of the plunger-side main body 61. Furthermore, the user is given a click sensation when the locking portion 33 overcomes the protrusion 64. In this embodiment, the screw groove is a passage portion 35 of the position adjustment portion 34, that is, a passage portion 35 for changing the correspondence between the positioning portion 32 and the locking portion 33, and constitutes a passage portion 35 that allows the locking portion 33 to move relative to a plurality of positioning portions 32. In this way, as the plunger-side member 6 and the barrel-side member 7 move relative to each other in the circumferential direction, the multiple positioning parts 32 and locking parts 33 move relative to each other in the circumferential direction, and when the locking part 33 overcomes the protrusion 64, the locking position and the unlocked position of the positioning part 32 and the locking part 33 are switched.

[0128] When the positioning portion 32 and the locking portion 33 are in the locked position, the contact surfaces 330 and 331 of the locking portion 33 come into contact with the contact surfaces 320 and 321 of the positioning portion 32, thereby locking the locking portion 33 axially to a pair of adjacent positioning portions 32 in the axial direction (Figure 24). In this embodiment, the contact surface 330 on the base end side of the locking portion 33 comes into contact with the contact surface 320 on the tip side of the positioning portion 32 located at the base end of the pair of positioning portions 32, thereby restricting the movement of the locking portion 33 toward the base end. Furthermore, the contact surface 331 on the tip side of the locking portion 33 comes into contact with the contact surface 321 on the base end side of the positioning portion 32 located at the tip of the pair of positioning portions 32, thereby restricting the movement of the locking portion 33 toward the tip. As a result, the axial movement of the plunger-side member 6 on which the positioning portion 32 is formed is restricted.

[0129] Furthermore, the locking portion 33 is fitted between two protrusions 64 located in one of the two rows of protrusions 64 that make up the row of protrusions 64, thereby restricting the radial movement of the plunger-side member 6 relative to the barrel-side member 7. Specifically, one circumferential end face of the locking portion 33 abuts against the other circumferential end face of the protrusion 64 located on one side of the two protrusions 64 in the screw groove, thereby restricting the movement of the locking portion 33 to one side in the circumferential direction. Also, the other circumferential end face of the locking portion 33 abuts against one circumferential end face of the protrusion 64 located on the other side of the two protrusions 64 in the screw groove, thereby restricting the movement of the locking portion 33 to the other side in the circumferential direction.

[0130] In this embodiment, the threads 63 and protrusions 64 of the plunger-side body 61 enable dispensing in increments of 0.1 ml. The pitch of the threads 63 corresponds to a dispensing volume of 0.1 ml. Specifically, the locking portion 33 of the barrel-side member 7 changes position by 0.1 ml when it moves half a rotation relative to the thread groove of the plunger-side body 61. Furthermore, by providing protrusions 64 on the plunger-side body 61 every half rotation of the thread groove, the dispensing volume can be adjusted in 0.1 ml increments with each click sensation caused by the locking portion 33 overcoming the protrusions 64. In this embodiment, the protrusion 64 located at the very tip corresponds to the maximum dispensing volume.

[0131] Furthermore, as shown in Figures 25 to 27, the plunger-side member 6 and the barrel-side member 7 may be moved relative to each other in a direction perpendicular to the axial direction, which is the direction of movement of the plunger 5 for discharging the contents, and in a direction different from the circumferential direction, thereby switching between the locked position and the unlocked position of one positioning part 32 and locking part 33. Specifically, the locked position and the unlocked position of the positioning part 32 and the locking part 33 may be switched by operating in the radial direction. This syringe 1 is a syringe that dispenses 2.25 ml of liquid medicine in amounts adjusted in 0.1 ml increments, and the components of the syringe body 2 are substantially the same as those shown in Figures 1 to 10.

[0132] The plunger regulating portion 30 of the adjustment device 3 is part of the plunger-side member 6. In addition, in the position setting mechanism 31 of the adjustment device 3, the positioning portion 32 is part of the barrel-side member 7, and the locking portion 33 is part of the plunger-side member 6.

[0133] The barrel-side main body portion 71 is substantially cylindrical. A position adjustment portion 34, which is a through hole, is formed in the barrel-side main body portion 71. The position adjustment portion 34 is composed of a plurality of positioning portions 32 and passage portions 35. A pair of position adjustment portions 34 are provided in the barrel-side main body portion 71 and are positioned 180° apart in the circumferential direction of the barrel-side main body portion 71.

[0134] The plunger-side member 6 comprises a plunger restricting portion 30 and a substantially cylindrical plunger-side main body portion 61. A piece portion 65 is provided on the outer circumferential surface of the plunger-side main body portion 61. The piece portion 65 is elastically deformable inward in diameter when pushed inward by the user. The piece portion 65 also includes a long portion 650 whose base end is connected to the outer circumferential surface of the plunger-side main body portion 61 and extends toward the tip, and a push-in portion 651 extending outward in diameter from the tip of the long portion 650 (Figure 27). A locking portion 33 extends circumferentially from one end of the long portion 650 in the circumferential direction. The dimension of the long portion 650 in the short direction is slightly smaller than the dimension of the passage portion 35 in the short direction. The push-in portion 651 is, for example, disc-shaped, but may be other plate-shaped. Furthermore, the diameter of the push-in portion 651 is larger than the dimension of the elongated portion 650 in the short direction. In other words, the locking portion 33 extends circumferentially at the tip of the elongated portion 650.

[0135] In this embodiment, the positioning portion 32 and the locking portion 33 can be switched from the locked position to the released position by pressing in the push-in portion 651 of the piece 65 (Figures 27(a) and 27(b)). Furthermore, by keeping the push-in portion 651 pressed in, the plunger-side member 6 and the barrel-side member 7 can move relative to each other in the axial direction while the positioning portion 32 and the locking portion 33 remain in the released position. Specifically, by pressing in the push-in portion 651, the locking portion 33 is pushed inward in diameter from the positioning portion 32, so that the plunger-side member 6 can move axially relative to the barrel-side member 7 without the locking portion 33 contacting the positioning portion 32. As a result, the locking portion 33 can move axially relative to multiple positioning portions 32 whose positions relative to the barrel 4 are fixed.

[0136] In the above embodiment, syringe 1 initially drew in more liquid than the maximum discharge volume into barrel 4, but it may also initially draw in the maximum discharge volume of liquid. Syringe 1 that initially draws in the maximum discharge volume into barrel 4 does not need to perform operations to determine the maximum discharge volume or to discharge an excess amount of liquid relative to the maximum discharge volume, and does not need to have configurations related to these operations.

[0137] In the above embodiment, the positioning parts 32, which are aligned in the axial direction, were arranged at equal intervals in the axial direction on the barrel-side main body 71, but this is not limited to this. For example, in a syringe 1 in which the discharge volume can be selected from three options: 0.1 ml, 0.3 ml, and 0.5 ml, the positioning parts 32, which are aligned in the axial direction, are arranged at different intervals.

[0138] In the above embodiment, the barrel-side member 7 is fixed to the barrel 4 and the plunger-side member 6 moves axially relative to the barrel-side member 7. However, it is also possible to configure the plunger-side member 6 to be fixed to the plunger 5 and the barrel-side member 7 to move axially relative to the plunger-side member 6.

[0139] Furthermore, other shapes with similar functions can be used for each component in syringe 1. [Explanation of Symbols]

[0140] 1...Syringe, 2...Syringe body, 3...Adjustment device, 4...Barrel, 5...Plunger, 6...Plunger side member, 7...Barrel side member, 8...Grip, 9...Detachable grip, 30...Plunger regulating part, 31...Position setting mechanism, 32, 32A, 32B...Positioning part, 33...Locking part, 34...Position adjustment part, 35...Passage part, 40...Tip part, 41...Base end part, 42...Connecting part, 43...Barrel reference part, 50...Rod, 51...Piston, 52...Shaft part, 53...Operating part, 54...Plunger reference part, 61...Plunger side body part, 62...Protrusion, 63...Thread, 64...Protrusion, 65...Single part, 70...Barrel contact part, 71...Barrel side body part, 72...Protrusion, 73...Single part, 80...Grip body part, 81...Grip extension part, 82...Claw, 90... Grip body, 91…Grip extension, 92…Recess, 320, 321…Surface to be contacted, 330, 331…Contact surface, 410…Opening, 411…Flange, 610…Slit, 611…First slit, 612…Second slit, 620…Horizontal surface, 621…Inclined surface, 650…Long section, 651…Indentation section, 700…Base end contact section, 701…Tip contact section, 702…Connection Part, 702A...First connecting part, 702B...Second connecting part, 710...Slit, 711...First slit, 712...Second slit, 713...Through hole, 714...Edge, 715...One side, 900...Syringe, 910...Outer cylinder, 920...Plunger, 926A...Convex part, 926B...Concave part, 930...Attachment, 931...Annular part, 932...Projection, 933...Rotation restricting part, N...Needle

Claims

1. A syringe body comprising a barrel capable of containing a substance, including a tip portion positioned at the axial end and capable of discharging the substance, and a base portion positioned at the axial base end and having an opening that communicates with the interior, and a plunger inserted into the barrel from the opening and moving toward the axial end to discharge the substance from the tip portion, is configured to adjust the discharge amount in the syringe body. A plunger restricting section that restricts the axial movement of the plunger toward the tip side, The system includes a position setting mechanism for setting the restricted position of the plunger restricting section, The position setting mechanism comprises a plurality of positioning parts arranged to have different axial positions, and a locking part that can be locked in the axial direction to each positioning part. The plurality of positioning parts and the locking part are configured to be movable relative to each other. An adjustment device in which the plurality of positioning parts and the locking part move relative to each other, and the locking part locks into one of the positioning parts to position it, thereby setting the restricting position of the plunger restricting part.

2. A plunger-side member having a plunger restricting portion that contacts the plunger in the axial direction to restrict the movement of the plunger toward the tip in the axial direction, The barrel side member has a barrel contact portion that contacts the barrel in the axial direction, thereby restricting the barrel's movement toward the tip in the axial direction, One of the plunger-side member and the barrel-side member has the plurality of positioning portions, and the other of the plunger-side member and the barrel-side member has the locking portion, The adjustment device according to claim 1, wherein, with the plunger-side member and the barrel-side member mounted on the syringe body, the plunger-side member and the barrel-side member move relative to each other, causing the plurality of positioning parts and the locking parts to move relative to each other.

3. The plurality of positioning parts and the locking part are such that the locking part can be relatively changed between a locking position in which it locks to one of the positioning parts in the axial direction and a release position in which it releases from one of the positioning parts. The adjustment device according to claim 2, wherein the plunger-side member and the barrel-side member move relative to each other in a circumferential direction around the axial direction, or in a direction perpendicular to the axial direction, thereby switching between the locked position and the released position of one of the positioning and locking parts.

4. The plurality of positioning parts and the locking part are such that the locking part can be relatively changed between a locking position in which it locks to one of the positioning parts in the axial direction and a release position in which it releases from one of the positioning parts. The adjustment device according to claim 2, wherein, with the plurality of positioning parts and the locking part in the release position, the plunger-side member and the barrel-side member move relative to each other in the axial direction, causing the plurality of positioning parts and the locking part to move relative to each other in the axial direction.

5. Of the plurality of positioning parts, the positioning part located furthest forward or base in the axial direction is the maximum positioning part, which determines the maximum discharge amount as the adjusted discharge amount for the amount of contents contained in the barrel. The adjustment device according to claim 1, wherein the position setting mechanism is configured such that the locking portion and the positioning portion are relatively movable, after restricting the axial movement of the plunger by the plunger restricting portion located at a restricted position in which the locking portion is locked to the maximum positioning portion, the locking portion is locked to a positioning portion other than the maximum positioning portion.

6. A syringe body comprising a barrel capable of containing a substance, the barrel including a tip portion positioned at the axial end and capable of discharging the substance, and a base portion positioned at the axial base end and having an opening that communicates with the interior, and a plunger inserted into the barrel from the opening and moving toward the axial end to discharge the substance from the tip portion, A syringe comprising an adjustment device according to any one of claims 1 to 5.

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