JP5602680B2 - Syringe cartridge - Google Patents

Description

  The present invention relates to a syringe cartridge which is attached to the distal end side of a syringe body and discharges the contents in the filling space by pushing a plunger, and in particular, a small amount of contents will be discharged quantitatively. It is what.

  A syringe used in the medical field is generally provided with a scale on the surface of a syringe (cylinder) like the syringe described in Patent Document 1, for example, which is pre-filled with contents. The same applies to a cartridge-type syringe in which the cartridge is attached to the syringe body, the contents are discharged by pushing the plunger, and the cartridge can be replaced with a new cartridge after use. The cartridge type syringe is set with the cartridge set on the syringe body and the needle is attached to the tip of the cartridge, for example, with the index finger and the middle finger supporting the syringe body and the thumb placed on the plunger. A predetermined amount of contents (medical solution) is administered to the patient by pushing the plunger to a predetermined position while viewing the screen.

JP 2002-306594 A

  By the way, although the conventional cartridge type syringe is provided with a scale, it is necessary to adjust the pushing amount of the plunger by adjusting the pressure of the finger, and some variation is inevitable. In particular, when the required amount is small, the amount of variation allowed for discharging the contents becomes more severe, and the operation becomes very difficult. In addition, it has been studied to fill the contents to be filled in the cartridge in an expected amount and to discharge all of the contents. However, when the syringe needle is attached to the tip of the cartridge, In order to reliably discharge air etc. existing in the injection needle, it is inevitable to discharge part of the contents together with the air, and the contents are still discharged in the expected amount. Was difficult. For this reason, it was still difficult to discharge even a small amount of contents in an accurate amount and with a simple operation.

  An object of the present invention is to propose an easy-to-use syringe cartridge that can discharge a small amount of contents quantitatively and can be realized with a simple configuration.

The present invention is a cartridge for a syringe that is attached to the distal end side of a syringe body and discharges the contents in the filling space by pushing a plunger,
The cartridge includes a cartridge main body including a distal end cylindrical body to which an injection needle is attached, and a piston that is slidably disposed in the cartridge main body and forms the filling space with the cartridge main body.
The piston is provided with a through hole that penetrates in the axial direction to form a tip opening toward the filling space, and when the piston is pushed out to discharge residual air in the injection needle together with a part of the contents, A piston stopper is provided to stop the pushing by contacting the rear end of the cartridge body,
The through-hole is slidably disposed between the piston, and the plunger pushes the tip of the plunger into the filling space so that a predetermined amount of content can be removed from the injection needle. It is a cartridge for syringes provided with the rod to discharge.

  It is desirable that the rear end portion of the rod is located on the front end side of the rear end opening of the through hole.

  The piston preferably includes a lid body that closes the rear end opening and is detachably attached.

  The piston preferably includes a detachable push-in preventing member that prevents the piston from being pushed between a rear end portion of the cartridge body and the piston stopper.

  The cartridge main body preferably includes a tip cover that is attached to the tip cylinder when the injection needle is not attached.

  Since the piston is provided with a piston stopper that abuts the rear end of the cartridge body, if the piston is pushed in until it stops, the residual air in the injection needle is surely discharged to fill the filling space and the injection needle with the contents. It can be in a filled state, and this is equivalent to the volume of the tip of the rod protruding into the filling space by pushing the rod slidably disposed in the through hole of the piston with the plunger. Even if a small amount of the contents to be processed can be discharged accurately. In addition, these operations related to the discharge of the contents (pushing the piston, pushing the plunger) do not need to be stopped halfway while looking at the scale, etc., and it is only convenient to push the piston and plunger all the way to the end. Become.

  If the rear end of the rod is located closer to the front end than the rear end opening of the through hole, the rod will not be touched directly when the piston is pushed in. The amount of contents discharged will not change from the expected amount.

  When the piston is provided with a lid that closes the rear end opening and is detachably attached, the unintentional contact with the rod can be surely prevented, so that the discharge amount of the contents does not change carelessly. .

  In the case where a detachable push-in preventing member is provided between the rear end portion of the cartridge body and the piston stopper, for example, inadvertent push-in of the piston in transportation or the like can be effectively prevented.

  When providing a tip cover to be attached to the tip cylinder of the cartridge body, the inside of the cartridge body can be sealed until just before the injection needle is attached, so that it is possible to effectively prevent entry of foreign matter into the cartridge body. Can do.

It is sectional drawing which follows the axial line of the cartridge of an injection needle non-attaching posture about an embodiment of a cartridge for syringes according to the present invention. FIG. 1A is a plan view and FIG. 1B is a bottom view of the cartridge shown in FIG. FIG. 2A is a plan view and FIG. 2B is a side view showing a push-in preventing member of the cartridge shown in FIG. 1. FIG. 1A is a sectional view of a cartridge in a posture in which an injection needle is not attached and an injection needle attached to the cartridge, and FIG. 1B is an attachment of the injection needle and a push-in preventing member removed. (C) is a cross-sectional view of the cartridge in a piston push-in completion posture in which the piston is pushed in until the piston stopper comes into contact with the rear end portion of the cartridge body. d) is a sectional view of the cartridge in a posture in which the syringe body can be mounted, with the lid removed. FIG. 5 is a partial cross-sectional view of the syringe main body and the plunger in a cartridge mounting completed posture in which the cartridge in the posture in which the syringe main body can be mounted shown in FIG. 4D is mounted on the syringe main body. FIG. 5A is a plan view and FIG. 5B is a bottom view of the syringe body and the plunger in the cartridge mounting completion posture shown in FIG. 5. It is a fragmentary sectional view which follows AA about the syringe main body and plunger of the cartridge installation completion attitude | position shown in FIG. FIG. 8 is a partial cross-sectional view of the syringe main body and the plunger in the plunger push-in completion posture in which the plunger is pushed down to the end with respect to the syringe main body and the plunger in the cartridge installation completion posture shown in FIG. 7.

Hereinafter, the present invention will be described more specifically with reference to the drawings.
FIG. 1 is a cross-sectional view taken along an axis of a cartridge in a posture in which an injection needle is not attached, according to an embodiment of a cartridge for a syringe according to the present invention. FIG. 2 is a plan view of the cartridge shown in FIG. (B) is a bottom view, FIG. 3 shows a push-in preventing member of the cartridge shown in FIG. 1, (a) is a plan view, (b) is a side view, and FIG. 1A is a cross-sectional view of a cartridge in a posture in which an injection needle is not attached and an injection needle attached to the cartridge, and FIG. 1B is a sectional view of the injection needle attached to the cartridge shown in FIG. FIG. 4C is a cross-sectional view of the cartridge in a removed injection needle mounting posture, and FIG. 5C is a cross-sectional view of the cartridge in a piston pushing-in completion posture in which the piston is pushed in until the piston stopper comes into contact with the rear end of the cartridge body. FIG. 5D is a cross-sectional view of the cartridge in a posture in which the syringe main body can be mounted, with the lid removed, and FIG. 5 shows the cartridge in the posture in which the syringe main body can be mounted shown in FIG. FIG. 6 is a partial cross-sectional view of the syringe main body and the plunger in the cartridge mounting completion posture mounted on the syringe main body, and FIG. 6A is a plan view of the syringe main body and the plunger in the cartridge mounting completion posture shown in FIG. FIG. 7B is a bottom view, and FIG. 7 is a partial cross-sectional view taken along the line AA of the syringe body and the plunger in the cartridge mounting completion posture shown in FIG. For the syringe body and plunger in the cartridge installation completion posture shown in FIG. 7, the plunger was pushed down to the end. It is a diagram.

In FIG. 1 and FIGS. 2A and 2B, reference numeral 1 denotes a cartridge body in the syringe cartridge. The cartridge body 1 has an opening 1a ₁ at the tip and a tip cylindrical body 1a whose outer diameter gradually increases toward the base, and is integrally connected to the tip cylindrical body 1a via an inclined portion and has a larger diameter than the tip cylindrical body 1a. An intermediate cylinder 1b, a main cylinder 1d that is integrally connected to the intermediate cylinder 1b via a step 1c, and has a larger diameter than the intermediate cylinder 1b, and radially outward from the rear end of the main cylinder 1d. It consists of the extended circular flange 1e. The inner surface of the intermediate cylinder 1 b is substantially parallel along the axis of the cartridge body 1. Then, the inner surface of the step portion 1c, inclined portions 1c ₁ is provided whose diameter increases toward the rear end side from the distal end side.

A piston 2 is slidably disposed in the cartridge body 1. The piston 2 forms a filling space M by liquid-tightly sealing the contents filled inside the cartridge body 1 together with a rod described later. Here, the filling space M refers to a region inside the cartridge main body 1 from the opening 1a ₁ of the front end cylinder 1a to the front end wall 2a ₁ of the piston 2. Further, a distal end cover, which will be described later, is attached to the distal end cylindrical body 1a, and the filling space M is filled with contents in advance. The contents may be filled in an amount that completely fills the filling space M, but may be filled in an amount smaller than the volume of the filling space M as shown.

The piston 2 has a front end wall 2a ₁ and is integrated with the front end 2a via a front end 2a that slides with the inner wall of the intermediate cylinder 1b, and an inclined portion 2b that expands from the front end to the rear end. A base 2c to be connected, and a through hole 2d penetrating the tip 2a and the base 2c along the axis are provided. A circular flange 2e (piston stopper) extending radially outward is formed at the rear end of the base 2c. The through hole 2d has a tip inner surface wall 2d ₂ that has a tip opening 2d ₁ that opens toward the filling space M and extends substantially parallel to the axis, and the tip inner surface wall 2d ₂ extends from the tip side. It is connected to the intermediate inner wall 2d ₄ via an inclined wall 2d ₃ whose diameter increases toward the rear end side. The intermediate inner wall 2d ₄ is connected to the rear inner wall 2d ₆ through an inclined wall 2d ₅ whose diameter increases from the front end side toward the rear end side, and the rear end inner wall 2d ₆ is described later. The rear end opening 2d ₇ is an insertion opening when the rod to be attached is attached.

Reference numeral 3 denotes a rod which is arranged in the through hole 2 d of the piston 2 and is concentrically doubled with the piston 2. The rod 3 has a distal end through a through hole 2d of the piston 2, particularly a distal end portion 3a that is slidably held in the inner surface wall 2d ₂ of the distal end, and an inclined portion 3b that expands from the distal end side toward the rear end side. An intermediate portion 3c that is integrally connected to the portion 3a, and a rod main body portion 3e that is integrally connected to the intermediate portion 3c via an inclined portion 3d that increases in diameter from the front end side toward the rear end side. Also, there is substantially on the same plane with the front end wall 2a ₁ of the front wall 3a ₁ and the piston 2 of the distal end portion 3a. On the inner side from the intermediate portion 3c to the rod main body portion 3e, a hole portion 3f is formed as a stealer, and the thicknesses of these portions are substantially the same. Incidentally rod 3 as shown is preferably not protruded from can not do so through holes 2d to touch inadvertently, the rear end portion 3g of the rod 3, the tip end side than the rear end opening 2d ₇ of the through hole 2d It is preferable to be located at.

  Reference numeral 4 denotes a push-in preventing member that is disposed between the flange 1e of the cartridge body 1 and the piston stopper 2e and prevents the piston 2 from being pushed in. As shown in FIGS. 3 (a) and 3 (b), the push-in preventing member 4 is integrally connected to a C-shaped coupling portion 4a having a circular part cut away, and on the side opposite to the cutout portion of the coupling portion 4a. The connecting portion 4b extends outward in the radial direction, and the holding portion 4c extends in both directions in a direction substantially orthogonal to the extending direction of the connecting portion 4b and has a T-shape between the connecting portion 4b. 1 and 2B, the push-in preventing member 4 is locked by fitting the coupling portion 4a to the base portion 2c of the piston 2 while holding and pulling the gripping portion 4c. Can be removed.

Reference numeral 5 denotes a lid that is detachably attached to the piston 2. As shown in FIG. 1, the lid body 5 includes a lid portion 5a that abuts against the rear end surface of the piston stopper 2e, and a cylindrical portion 5b that stands up from the lid portion 5a. insert the end opening 2d ₇ is fitted with a rear end inner surface wall 2d _6, it closes the through hole 2d. Incidentally, in a state where the front end wall 2a ₁ of the front wall 3a ₁ and the piston 2 of the rod 3 as shown are on substantially the same plane, the distal end portion 5b ₁ of the cylindrical portion 5b to the rear end portion 3g of the rod 3 equivalents It is preferable to contact.

  Reference numeral 6 denotes a distal end cover that is mounted on the distal end cylindrical body 1a of the cartridge main body 1 in an unmounted posture of the injection needle described later. The front end cover 6 includes a circular wall 6a and an annular peripheral wall 6b integrally connected to the edge of the circular wall 6a, and the inside of the filling space M is sealed by fitting the peripheral wall 6b into the front end cylindrical body 1a. Can do. The front end cover 6 may be attached to the front end cylindrical body 1a by screwing.

  4A, reference numeral 7 denotes an injection needle that is attached to the distal end cylindrical body 1a of the cartridge body 1 after the distal end cover 6 is removed. The injection needle 7 is stored in a protective case C or the like when not in use, for example. Various types of injection needles 7 can be used. In the illustrated example, the needle portion 7b is attached to the base portion 7a, and the base portion 7a is pushed into the distal end cylindrical body 1a to the cartridge body 1. The installation of is now complete. In addition, you may make it mount by providing a screw part in the base part 7a and the front-end | tip cylinder 1a, and screwing together.

Cartridge constructed as described above, the piston 2 Upon attachment to the cartridge body 1, the tip portion 2a, since it is derived the inclined portion 1c ₁ of the cartridge body 1, to be easily inserted into the intermediate tubular member 1b it can. Also, when mounting the rod 3 with the piston 2, the distal end portion 3a of the rod 3, because it is induced to the inclined wall 2d ₃ of the piston 2 can be easily inserted into the front end inner surface wall 2d _2.

  The discharge of the contents by the cartridge is performed by removing the push-in prevention member 4 and the tip cover 6 from the cartridge in the non-injection posture shown in FIG. 4A and removing the injection needle 7 as shown in FIG. Installing. Although air exists in the filling space M and the injection needle 7, these air are discharged by a method described later.

Next, as shown in FIG. 4C, the lid 5 is pressed in the direction of the arrow with the injection needle 7 facing upward, and the piston 2 is slid along the axis along with the rod 3. Then, the pressing is continued until the piston stopper 2e comes into contact with the flange 1e of the cartridge main body 1 to displace the syringe main body mountable posture shown in FIG. Thereby, the residual air in the filling space M and the injection needle 7 is discharged together with some contents, and the filling space M and the inside of the injection needle 7 are filled with the contents. In this case, the sliding resistance (tip part 2a between the sliding resistance between the rod 3 and the piston 2 (sliding resistance between the tip portion 3a and the distal inner surface wall 2d _2), the piston 2 and the cartridge body 1 And the inner wall of the intermediate cylinder 1b), the rod 3 can be moved stably along with the slide of the piston 2, but as shown in the figure, If the front end portion 5b ₁ is brought into contact with the rear end portion 3g of the rod 3, the rod 3 can be prevented from being displaced with respect to the piston 2 during the slide. Note that increasing the sliding resistance, for example, to the inner diameter of the distal inner surface wall 2d ₂ of the piston 2, it is sufficient to slightly increase the outer diameter of the distal end portion 3a of the rod 3.

  Thereafter, the cartridge in a posture in which the syringe body can be mounted is mounted on the syringe body 8 as shown in FIG. Here, the syringe body 8 includes a flange 8b having a U-shape in a plan view, as shown in FIG. 6A, on the distal end side of the cylindrical body portion 8a. The front end side of the flange 8b has a front wall 8c that is also U-shaped in plan view with an interval in the axial direction, and the edge of the flange 8b and the edge of the front wall 8c are connected by a side wall 8d. Thus, a groove 8e is defined on the inside thereof. In the cartridge in the posture in which the syringe main body can be mounted shown in FIG. 4D, the overlapping thickness of the flange 1e and the piston stopper 2e is substantially equal to the groove width dimension of the groove 8e. For this reason, the cartridge is sandwiched between the flange 8b and the front wall 8c by inserting the flange 1e and the piston stopper 2e into the groove 8e in a state of being overlapped. As a result, the piston 2 is pushed in to discharge the residual air in the injection needle 7 and the cartridge 5 cannot be attached to the syringe body 8 unless the cover 5 is removed. An undetached cartridge is not erroneously attached to the syringe body 8, and erroneous operation can be prevented.

  Further, an axial direction intermediate portion of the body portion 8a has a finger hook portion 8f that is elliptical in plan view as shown in FIGS. 6 (a) and 6 (b), and as shown in FIGS. A rectangular window hole 8g is formed. In the illustrated example, a total of two window holes 8g are provided at positions facing each other across the axis. As shown in FIGS. 5 and 7, a step portion 8 h is formed on the inner wall on the rear end side of the body portion 8 a.

A plunger 9 is provided inside the syringe body 8. The plunger 9 has a circular plate 9b on the rear end side of the cylindrical tip portion 9a having a small diameter, and extends from the circular plate 9b to the rear end side along the axis and has a cross-shaped cross section. A jar main body portion 9c is provided, and an operation portion 9d is provided at the rear end portion of the plunger main body portion 9c. An elastic piece 9e is provided at a position corresponding to the window hole 8g at an intermediate portion in the axial direction of the plunger main body 9c. Further, a step portion 9 f is formed on the rear end side of the plunger main body portion 9 c, and a spring S is disposed between the step portion 8 h of the syringe main body 8. Thus the plunger 9, while being urged toward the rear end side by the elastic force of the spring S, retaining the locking end 9e ₁ of the elastic pieces 9e are engaged with the edge 8g ₁ of the window hole 8g Is retained.

  Thereafter, when the operation portion 9d of the plunger 9 is pushed in the direction of the arrow shown in FIG. 8, the tip portion 9a of the plunger 9 comes into contact with the rear end portion 3g of the rod 3, and the rod 3 is pushed toward the tip side. As a result, the tip 3a of the rod 3 protrudes into the filling space M. When the plunger 9 continues to be pressed, the disk 9b of the plunger 9 comes into contact with the piston stopper 2e and the protrusion of the tip 3a is stopped. Here, before the tip portion 3a is projected into the filling space M, the inside of the filling space M and the injection needle 7 is filled with the contents. The content corresponding to the volume of the body 3a sliding into the filling space M is discharged from the tip of the injection needle 7. Thereby, even if it is a small amount of contents, a predetermined amount can be discharged accurately.

  In addition, you may make it the operation part 9d and the rear-end part of the trunk | drum 8a contact | abut the stop of pushing of the plunger 9. FIG. Further, the cartridge according to the present invention can be used in a lever type syringe that discharges the contents in the cartridge by checking the lever instead of the syringe body 8 and the plunger 9 described above.

  ADVANTAGE OF THE INVENTION According to this invention, a small amount of contents can be discharged | emitted by fixed_quantity | quantitative_quantity, Furthermore, the easy-to-use syringe which can be implement | achieved by simple structure can be provided.

DESCRIPTION OF SYMBOLS 1 Cartridge body 1a Front end cylinder 2 Piston 2a Front end 2d Through hole 2d ₁ Front end opening 2d ₇ Rear end opening 2e Flange (piston stopper)
DESCRIPTION OF SYMBOLS 3 Rod 3a Front-end | tip part 3g Rear-end part 4 Push-in prevention member 5 Lid body 6 Front-end cover 7 Injection needle 8 Syringe main body 9 Plunger M Filling space

Claims (5)

A syringe cartridge that is attached to the distal end side of the syringe body and discharges the contents in the filling space by pushing the plunger,
The cartridge includes a cartridge main body including a distal end cylindrical body to which an injection needle is attached, and a piston that is slidably disposed in the cartridge main body and forms the filling space with the cartridge main body.
The piston is provided with a through hole that penetrates in the axial direction to form a tip opening toward the filling space, and when the piston is pushed out to discharge residual air in the injection needle together with a part of the contents, A piston stopper is provided to stop the pushing by contacting the rear end of the cartridge body,
The through-hole is slidably disposed between the piston, and the plunger pushes the tip of the plunger into the filling space so that a predetermined amount of content can be removed from the injection needle. A syringe cartridge comprising a rod for discharging.   The syringe cartridge according to claim 1, wherein a rear end portion of the rod is positioned on a front end side with respect to a rear end opening of the through hole.   The syringe cartridge according to claim 2, wherein the piston includes a lid body that closes the rear end opening and is detachably attached.   The syringe cartridge according to any one of claims 1 to 3, wherein the piston includes a detachable push-in preventing member that prevents the piston from being pushed between a rear end portion of the cartridge main body and the piston stopper.   The cartridge for a syringe according to any one of claims 1 to 4, wherein the cartridge body includes a distal end cover that is mounted on the distal end cylindrical body when the injection needle is not mounted.

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