JP6294440B1 - Prefilled syringe - Google Patents

Abstract

An object of the present invention is to prevent excessive ejection and leakage of liquid during mixing and dissolution of a drug and a chemical solution in a prefilled syringe with bypass. In the present invention, a front chamber 6 and a rear chamber 7 for accommodating a first component and a second component, respectively, are formed in a cylindrical main body 1, and the front chamber 6 and the rear chamber 7 are formed in the main body 1. It is inserted and partitioned by a plug body 3 that is elastically pressed against the inner peripheral surface thereof to form a plurality of circumferential ribs R, and the inner peripheral surface of the main body 1 is in front when the plug body 3 passes through. In the prefilled syringe having a recess 13 for communicating the chamber 6 and the rear chamber 7, the rib R has an outer diameter D1 exceeding the inner diameter D0 of the main body 1 on the front outer periphery other than the rear end of the plug 3. R1 and a high-pressure release end rib R2 formed on the outer periphery of the rear end of the plug body 3 with an outer diameter D2 which is equal to or larger than the inner diameter D0 and less than the outer diameter D1 of the standard rib R1. It is said. [Selection] Figure 3

Description

  In this invention, for example, a powder medicine and a chemical solution are stored in advance in two chambers, a front chamber and a rear chamber in a syringe, and a chemical solution in the rear chamber is passed through a bypass by pressing and moving an internal gasket (plug) at the time of use. The present invention relates to a prefilled syringe that is fed into a front chamber containing powder, mixed into a solution, and used as an injection solution.

  Conventionally, the prefilled syringes with bypass as described above are known in Patent Documents 1 and 2, both of which are ejected when the chemical solution in the rear chamber is ejected to the front chamber through the bypass by pressurization. Due to its strong momentum, the liquid leaks into the solution take-out chamber further forward from the front chamber, and prevents the liquid from reaching the injection needle attached to the tip of the syringe and leaking outside.

  In the invention of Patent Document 1, the front chamber 6 and the rear chamber 7 are partitioned, and a gasket (plug body) that opens the bypass 1a and communicates the two chambers by moving forward is divided into two, and both gaskets 51, The axial ribs 64, 65, 86, 87 are formed between the adjacent ribs 52, and the axial grooves 70, 71 for communicating the annular recesses 59, 60 are formed on the outer periphery on the front end side of the front gasket 51, and the bypass 1 a is used. The momentum of the ejection of the chemical solution from the rear chamber to the front chamber is reduced.

  In the invention of Patent Document 2, the volume VS including a part of the first chamber and the front plug 6 when the middle plug 7 reaches the rear end of the bypass 14 in the syringe is equal to or less than the volume VC of the liquid component 75. % Or more to relieve the strong momentum of the chemical solution from the rear chamber to the front chamber.

JP 2002-263186 A Japanese Patent No. 4884769

  However, the syringe gasket of the above-mentioned Patent Document 1 has a shape of gasket such as a plug body (gasket) that divides the front chamber and the rear chamber divided into two parts, and a complicated passage needs to be formed on the outer periphery of the plug body. In addition to the complexity of the structure and high cost as a whole, higher quality control is required, and the fine flow path has the disadvantage of being easily accompanied by accidents such as clogging.

  The syringe of Patent Document 2 calculates and calculates a relative numerical value of the total volume VS of a part of the syringe and the stopper body under a certain fluid condition and the volume VC of the liquid accommodated in the rear chamber. For example, the amount of liquid (medical solution) is determined in relation to the amount and quality of the powdered drug, the technical elements are unstable, and the quality control of the syringe of the present invention also includes unstable elements. There is.

The prefilled syringe of the present invention for solving the above-mentioned problems is formed by first forming a front chamber 6 and a rear chamber 7 for accommodating a first component 14 and a second component 16 in a cylindrical main body 1, respectively. , front chamber 6 and the rear chamber 7 is inserted into the body 1, the partition by stopper 3 formed ribs R of plural rows circumferential direction is resiliently pressed against the inner peripheral surface of the main body 1 In the prefilled syringe in which a bypass 13 is provided in the inner peripheral surface of the main body 1 so as to allow the front chamber 6 and the rear chamber 7 to communicate with each other when the plug body 3 passes, the rib R is other than the rear end of the plug body 3. outer diameter D ₁ of the the standard rib R ₁ having an outer diameter D ₁ exceeds the internal diameter D ₀ of the main body 1 in the front outer periphery, there is the internal diameter D ₀ or the rear end outer periphery of the plug 3 of the standard rib R ₁ less than an outer diameter and a end ribs R ₂ for high pressure release formed in the D _2, cross-section a along the axis of the end portion rib R ₂ Is formed in a guru-shaped chevron, the peripheral surface of the rear side is being formed into a tapered surface inclined towards the axis.

Second , the standard rib R ₁ is characterized in that the cross section is formed in an arcuate chevron.

Third, the first component by moving the plug member for partitioning between the front chamber 6 and the rear chamber 7 and Chusentai 3, pressurized forward by forward movement of Chusentai 3 in front of the front chamber 6 14 and the front plug body 2 that discharges the solution of the second component 16 to the outside of the main body 1 is formed by projecting the front end face of the inner plug body 3 in a mountain shape, and the rear end face of the front plug body 2 is formed. It is characterized in that it is formed in a concave shape so as to overlap and fit with the front end of the inner plug body 3.

  The prefilled syringe of the present invention configured as described above is a rear chamber when the end rib of the plug body that partitions the front chamber and the rear chamber passes through the rear end of the bypass between the chambers by pressing from the syringe rear end side. Since the internal pressure of the end rib is gradually and gently released into the bypass and the front chamber by the inclined (tapered) surface of the rear peripheral surface of the end rib, the conventional standard rib of the plug body is pushed and moved. Rather than being released instantly from the high internal pressure of the rear chamber, the momentum of the liquid ejection of the rear chamber is reduced, and the liquid chemical is ejected into the front chamber with a strong momentum through the bypass without being mixed or undissolved. By doing so, there is an advantage that problems such as ejection from the front solution take-out chamber and the injection needle at the tip are solved.

  In addition, by simply setting the rib shape and dimensions of the rear end of the plug body to a height less than the height of the standard rib, and forming it into a mountain shape having an angled apex, the internal pressure of the rear chamber is passed when the bypass rear end passes. The end rib is gradually deformed by an early stage, and the flow path of the chemical liquid to the bypass is gradually widened by the taper surface of the end rib. As a result, the pressure in the rear chamber is gradually and gradually released. .

  Furthermore, there is no need to set the internal cavity and the volume ratio of the flow rate, and the insertion position of the front plug can be set to the front end side of the main body. An increase in dynamic resistance can be avoided.

  In addition, since the pressure can be released only by a simple technical element that constitutes the rear end rib as described above, there are advantages that the shape and structure are simple and low cost, and the operation is reliable.

  Other than the technology of Patent Document 1, the shape structure is not complicated and the cost is not increased, and the fluid element such as the amount of the chemical solution is not used as a technical element as in the technology of Patent Document 2. Maintenance is also easier.

  In addition, it is possible to facilitate mixing and dissolution of chemicals and powders in the front chamber by forming the tip of the inner plug into a chevron and forming the rear end of the front plug in a concave shape that matches the chevron. The remaining amount of the chemical at the time of injection can be surely reduced.

It is a whole sectional view showing the state before pushing operation of the syringe of the present invention. It is principal part sectional drawing which shows the state in which the inside plug body during pushing operation of a syringe passes a bypass. It is a partially expanded sectional view of the said principal part sectional drawing.

  1 to 4 show an embodiment of the present invention. As shown in FIG. 1, the syringe of the present invention has a longitudinal length of about 85 mm and a transparent glass or plastic cylindrical body 1 with an inner diameter of 10.5 mm. On the other hand, the front plug body 2, the middle plug body 3 and the rear plug body 4 made of rubber or plastic material having elasticity are respectively movable at the front end, the rear end, and the middle portion so that they can move left and right and are airtight. The front chamber 6 and the rear chamber 7 are formed by the inner plug body 3.

  A cylindrical needle mounting cap 8 is fitted and fixed to the opened front end of the main body 1, and a boss portion 8 a for removably mounting an injection needle (not shown) is formed at the center of the distal end side. A cap mounting portion 8b is formed to insert a base end portion of the protective cap (not shown) in a detachable manner. A cylindrical front and rear two-stage peripheral wall is formed on the rear side of the needle mounting cap 8, and the front half receives the front plug body 2 when it is pushed out from the front end of the syringe body 1. An extraction chamber 8c is formed through which the drug solution that has flowed into the tube is sent to the injection needle through the boss portion 8a.

  Further, a collar portion 8d fitted to the outer periphery of the opened front end of the main body 1 is integrally provided on the rear end side. A passage through which an injection solution (drug solution) passes forwardly between the inner periphery and the outer periphery of the front plug body 2 when the front plug body 2 is extruded and accommodated in the inner periphery of the extraction chamber 8c A groove for forming the rib, a rib 8e for supporting the front plug body 2, and the like are provided.

  A flange-like collar 9 protrudes from the outer periphery of the rear end, which is the open end of the main body 1, and a finger hook 11 that hangs two fingers up and down during the injection operation is detachably attached to the collar 9. ing. In addition, the front end of a rod 12 (presser) for pushing the rear plug body 4 into the interior thereof at the time of injection operation is screwed and fixed at the center of the rear end of the rear plug body 4, and the rod 12 has a cross-shaped cross section as shown in the figure. Circular reinforcing plates 12a are integrally formed at regular intervals.

  A groove-like shape having an axial total length slightly longer than the length of the cylindrical outer peripheral portion of the inner plug body 3 on the inner surface of the passage position of the inner plug body 3 at a position slightly forward of the front and rear centers of the cylindrical main body 1 of the syringe. A bypass 13 is recessed. A powdery drug (first component) 14 to be dissolved is accommodated in the front chamber 6, and distilled water or other chemical solution (second component) 16 for dissolving the drug 14 is accommodated in the rear chamber 7 in advance. This structure is known as a prefilled syringe with a bypass as a whole.

  In the prefilled syringe, when the cap for the injection needle is removed in advance and the rear end portion of the rod 12 is pushed into the main body 1 from the state shown in FIG. When the body 3 moves forward in the main body 1, the inner plug body 3 reaches the bypass 13 as shown in FIGS. 2 and 3, and the rear end of the outer periphery passes the rear end of the bypass 13. 7 chemical solution 16 flows into the anterior chamber 6 through the bypass 13 and is mixed with the drug 14 to be dissolved. After confirming this dissolution, when the rod 12 is pushed further to advance the inner plug body 3, the front plug body 2 is pushed into the take-out chamber 8c, and a solution (injection solution) is formed on the outer periphery of the front plug body 2. To the injection needle through the flow path.

  As described above, in the conventional prefilled syringe with bypass, when the rear end of the outer periphery of the inner plug body 3 passes the rear end of the bypass 13, if the pressing force of the rod 12 is strong, the chemical solution 16 in the rear chamber 7 is applied. Since the applied pressure is too high, the momentum (kinetic energy) of the chemical liquid ejected from the bypass 13 into the front chamber 6 is increased, and the front plug body 2 is pushed out and leaks from the injection needle through the extraction chamber 8c. is there. For this reason, in the present invention, in order to solve this problem, the inner plug body 3 is configured as described below.

As shown in FIGS. 1 to 3, a plurality of (three in this example) ribs R in the circumferential direction are formed on the outer circumferences of the plugs 2 to 4 in a circular arc-shaped cross section that is a standard shape. Between the ribs R, grooves G each having an arcuate valley-shaped cross section are formed. In this example, the inner diameter D ₀ of the syringe body 1 is 10.5 mm, whereas the outer diameter D ₁ of the rib R of each plug 2 to 4 is about 10.9 mm, and the outer diameter D ₃ of the groove G is 10.4 mm. When it is 1 mm and is inserted and fitted into the main body 1, the rib R and the groove G are elastically deformed and brought into pressure contact with each other, so that the sealing performance (tightness) with the inner peripheral surface of the main body 1 is maintained.

In the present embodiment, the rib R of the inner plug body 3 that passes through the bypass 13 portion is shown as a standard rib R ₁ having three standard arcuate cross sections on the front side and a rearmost rib. is constituted by the end ribs R ₂ formed in the chevron cross-section with an apex angle-shaped (or reverse V-shape). The front surface of the end rib R ₂ is formed in a direction perpendicular to the axial center of the main body 1 toward the front and rear center (valley bottom) of the arc-shaped groove immediately before the end rib R ₂ , and the rear surface (outer peripheral surface) is the axial center. On the other hand, the taper surface which inclines to gentle acute angle inclination (theta) (around 15 degrees) is formed, for example with the length of 0.8-1.2 mm. In Figure 3, the V-shaped groove formed in the immediately preceding end ribs R _2, relative to the groove G ₁ of other standard arcuate, expressed as an end groove G _2. The outer diameter D ₂ of the end rib R ₂ is the same as or slightly larger than the inner diameter D _{0 of the} main body 1. In this example, the outer diameter D ₄ of the rear end portion of the inner plug body 3 is 10.1 mm, which is the same as the outer diameter D _{3 of the} grooves G ₁ and G ₂ .

This structure, when upon Chusentai 3 is advanced by pressure applied by the rod 12, Figure 3, outer peripheral edge of the end ribs R ₂ as shown in FIG. 4 through the rear end position of the bypass 13, the rear chamber chemical 16 by 7 internal pressure of the can is guided along the inclined taper surface is a rear peripheral surface of the end ribs R _2, while the outer peripheral end of the angled edge ribs R ₂ is resiliently deformed bypass 13 Flows relatively slowly into the front chamber 6.

At this time, since the end rib R ₂ has a lower contact pressure to the inner peripheral surface of the main body 1 and a smaller contact surface than the standard rib R ₁ , the rear end of the inner plug body 3 is the rear end of the bypass 13. Even before the pressure reaches, the elastic deformation of the rear chamber 7 is relatively low and the chemical solution is fed into the bypass 13 to further reduce the rear peripheral surface of the end rib R ₂ of the inner plug body 3. The gap with the inner peripheral surface of the main body 1 is gradually increased in a tapered shape. For this reason, the inflow amount of the chemical liquid 16 into the front chamber 6 is gradually increased, and it is possible to prevent the chemical liquid from being ejected with a strong momentum due to the rapid inflow.

  Further, the front end surface of the inner plug body 3 is formed so as to project into a conical mountain shape. On the other hand, the rear surface of the front plug body 2 overlapping the front surface of the inner plug body 3 is connected to the front surface of the inner plug body 3. It is formed in a bowl-shaped recess so as to closely overlap. With this mechanism, there is an advantage that the injection solution is discharged without remaining in the front chamber 6 due to the close contact of the uneven surface when the plug bodies 2 and 3 overlap each other.

  Other minute projections on the front surface of the front plug body 2, the rear surface of the inner plug body 3, and the front and rear surfaces of the rear plug body 4 so as not to adhere and adhere to each other when pressed against other surfaces Reference numerals 17 are provided in a protruding manner. Reference numerals 18a and 18b denote positions of display lines that are printed and displayed in a strip shape on the peripheral surface of the main body 1 in order to provide a guide for the action position or stop position of the inner plug body 3 and the rear plug body 4, respectively.

1 (Syringe) body 2 Front plug body 3 Medium plug body (plug body)
4 Rear plug body 6 Front chamber 7 Rear chamber 8 Needle mounting cap 12 Rod 13 Bypass 14 Drug (first component)
16 chemical (second component)
D ₀ Body inner diameter D ₁ Standard rib outer diameter D ₂ End rib outer diameter R Rib R ₁ Standard rib R ₂ End rib

Claims (3)

A front chamber (6) and a rear chamber (7) for accommodating the first component (14) and the second component (16), respectively, are formed in the cylindrical main body (1), and the front chamber (6) and the rear chamber are formed. (7) is inserted into the main body (1) within the plug forming the body (1) is resiliently pressed against the inner peripheral surface of the circumferential direction of the plural rows of ribs (R) (3) In the prefilled syringe in which a bypass (13) for communicating the front chamber (6) and the rear chamber (7) is recessed on the inner peripheral surface of the main body (1) when passing through the plug (3), A standard rib (R ₁ ) in which the rib (R) has an outer diameter (D ₁ ) exceeding the inner diameter (D ₀ ) of the main body (1) on the front outer periphery other than the rear end of the plug (3); body ends for pressure release, which is formed on an outer diameter less than the outer diameter (D ₁₎ (D ₂₎ of the rear periphery to the inside diameter (D ₀₎ Exceeded by standard ribs (R ₁₎ (3) ribs (R ₂ With the door, prefilled the cross section along the axis of the end ribs (R ₂₎ is is formed in a chevron angle-shaped, the peripheral surface of the rear side is formed in a tapered surface inclined towards the axis Syringe. Prefilled syringe according to claim 1, the cross section of the standard ribs (R ₁₎ is formed in a circular arc shape of the chevron. The plug body that partitions the front chamber (6) and the rear chamber (7) is the middle plug body (3), and is moved in front of the front chamber (6) by being pressurized by the forward movement of the middle plug body (3). By providing the front plug body (2) for discharging the solution of the first component (14) and the second component (16) to the outside of the main body (1), the front end face of the inner plug body (3) is shaped like a mountain. project was formed on, according to any of the previous plug body (2) rear surface Chusentai (3) according to claim 1 or 2 was formed by recessed concave to fit overlap the front end of the Prefilled syringe.

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