JP5695484B2 - Syringe - Google Patents

Description

  The present invention relates to a syringe, and in particular, intends to discharge a small amount of contents quantitatively.

  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, and the syringe is sandwiched between the index finger and the middle finger, for example. In a state where it is supported, the plunger is pushed in with the thumb while looking at the scale, whereby a predetermined amount of contents (medical solution) is administered to the patient.

JP 2002-306594 A

  By the way, although the conventional syringe as described in the above-mentioned Patent Document 1 has a scale, it is necessary to adjust the pushing amount of the plunger by adjusting the pressure of the finger, and there is some variation. Can not escape. 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 a syringe with a predetermined amount of contents in advance and then discharge all of the contents. However, the air that enters the syringe needle when it is attached to the syringe or the air that originally exists in the syringe needle In order to reliably discharge the contents, it is inevitable to discharge a part of the contents together with the air, and it is still difficult to discharge the contents in the expected amount. For this reason, the appearance of a new syringe that can be discharged with a simple operation even with a small amount of contents has been strongly desired.

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

The present invention relates to a syringe having a tip cylinder for mounting an injection needle, a piston that is slidably disposed in the syringe and forms a filling space for contents inside the syringe, and is connected to the piston. And a plunger for discharging the contents in the filling space from the tip of the injection needle by a slide accompanying the addition of a pushing force,
The piston has a central opening penetrating in the axial direction toward the filling space;
The plunger has an inner space connected to the central opening, and the tip end portion is always exposed to the filling space and is slidably held in the central opening. Provide a double-positioned rod,
On the outer side of the plunger, a locking end is formed to stop the pulling back of the plunger for introducing the contents into the filling space with a predetermined pulling back amount in association with a window hole end provided in the syringe,
When pushing the plunger that discharges residual air in the filling space together with a part of the contents to the rear end of the plunger, the pushing is stopped by contact with a finger hook provided at the rear end of the syringe. Forming a plunger stopper,
The rod, the tip protrudes into the filling space at pushing of the rod, the contents which by the contact between the plunger according to the protrusion of the tip portion is stopped at a predetermined projection amount a syringe and having a rod stopper for stopping at a predetermined amount of discharge of.

  The locking end is preferably the other end of an elastic piece having one end connected to the plunger.

  The plunger preferably includes a detachable cover that contacts the rear end of the rod and slides the rod when the plunger is pushed.

  The cover is preferably connected to the plunger stopper via a hinge.

  It is desirable that the syringe includes a distal end cover that is attached to the distal end cylindrical body when the injection needle is not attached.

  Since the plunger is provided with a locking end that stops pulling back of the plunger when the content is introduced into the filling space, the plunger is not lifted too much and the content may be introduced excessively. Absent. In addition, a rod that is slidably held in the central hole provided in the piston and is arranged concentrically with the plunger inside the plunger is provided, and further, the plunger stopper is attached to the syringe finger holder. By abutting, the remaining air in the filling space is discharged together with a part of the contents, and the remaining contents are left in the filling space to stop the pushing, and in addition, the tip part related to the pushing of the rod While the contents are discharged from the injection needle by protruding into the filling space, the rod stopper comes into contact with the plunger and the tip is stopped at the specified protruding amount. Can be discharged accurately. In addition, the operation related to the discharge is easy to use because the plunger and the rod need only be pushed in until the respective stoppers come into contact with each other.

  When the other end of the elastic piece with one end connected to the plunger is used as a locking end that stops the pulling back of the plunger, the locking end can be integrated with the plunger, reducing the number of parts. Since the elastic piece bends, the assembly workability is not impaired when the plunger is attached to the syringe.

  If the plunger is provided with a detachable cover that contacts the rear end of the rod and slides the rod as the plunger is pushed in, the rod will be inadvertently displaced because it will not touch the rod. In addition, since the rod slides without being displaced while the plunger is pushed in, the amount of contents does not change from the expected amount.

  When the cover and the plunger stopper are connected via a hinge, not only the number of parts can be reduced, but also the cover can be opened with one hand, so that the usability can be improved.

  In the case of providing a tip cover attached to the tip cylindrical body of the syringe, since the inside of the syringe can be sealed until just before the injection needle is attached, it is possible to effectively prevent entry of a foreign substance or the like into the syringe.

(A) is sectional drawing which follows the axis line of the syringe of a syringe needle non-attachment posture about embodiment of the syringe according to this invention, (b) is sectional drawing which follows AA shown in (a), c) is a sectional view taken along line BB shown in FIG. It is a top view of the syringe shown in FIG. It is a bottom view of the syringe shown in FIG. FIG. 2 is a cross-sectional view of the syringe shown in FIG. 1 in a non-wearing posture and a syringe needle attached to the syringe. FIG. 5 is a cross-sectional view of a syringe equipped with a syringe needle mounted with the syringe needle shown in FIG. 4. It is sectional drawing of the syringe of the content introduction completion posture which introduce | transduced the content into the syringe shown in FIG. FIG. 7 is a cross-sectional view of the syringe in a plunger push-in completion posture in which the plunger of the syringe shown in FIG. 6 is pushed in until the plunger stopper comes into contact with the finger hook portion of the syringe. It is sectional drawing of the syringe of the cover removal attitude | position which opened the cover of the syringe shown in FIG. It is sectional drawing of the syringe of the rod pushing completion posture which pushed the rod of the syringe shown in FIG. 8 until the rod stopper contact | abutted with the plunger. It is sectional drawing of the syringe of an injection needle mounting posture which shows other embodiment of the syringe according to this invention. FIG. 10 is a cross-sectional view of a syringe in a needle mounting posture, showing still another embodiment of the syringe according to the present invention.

Hereinafter, the present invention will be described more specifically with reference to the drawings.
1A is a cross-sectional view taken along an axis of a syringe in a posture in which a syringe needle is not mounted, and FIG. 1B is a cross-sectional view taken along A-A shown in FIG. (C) is a cross-sectional view taken along line BB shown in (a), FIG. 2 is a plan view of the syringe shown in FIG. 1, and FIG. 3 is a bottom view of the syringe shown in FIG. FIG. 4 is a cross-sectional view of the syringe in the non-injection posture shown in FIG. 1 and the injection needle attached to this syringe, and FIG. 5 is equipped with the injection needle shown in FIG. FIG. 6 is a cross-sectional view of a syringe in a posture to which a needle is attached, and FIG. 6 is a cross-sectional view of the syringe in a content introduction completion posture in which the content is introduced into the syringe shown in FIG. Push the plunger of the syringe shown until the plunger stopper touches the finger hook of the syringe. FIG. 8 is a cross-sectional view of the syringe in an end position, FIG. 8 is a cross-sectional view of the syringe in a cover-removing position with the cover of the syringe shown in FIG. 7 open, and FIG. 9 is a cross-sectional view of the syringe rod shown in FIG. FIG. 10 is a cross-sectional view of a syringe in a rod push-in completion posture in which the rod stopper is pushed into contact with the plunger, and FIG. 10 shows another embodiment of the syringe according to the present invention. FIG. 11 is a cross-sectional view of a syringe in a needle mounting posture, showing still another embodiment of the syringe according to the present invention.

In FIG. 1A, FIG. 2, and FIG. 3, 1 is a syringe. Syringe 1, the intermediate comprising a tip tube body 1a having an outer diameter gradually increasing toward the base having a front end opening 1a _1, the larger diameter than the distal cylinder 1a integrally connected via an inclined portion tip tube body 1a A cylindrical body 1b, a syringe body 1d that is integrally connected via the intermediate cylinder 1b and the stepped portion 1c and has a larger diameter than the intermediate cylinder 1b, and a circle that extends radially outward from the rear end of the syringe body 1d It consists of a flange (finger holding part) 1e having a shape and a window hole 1f that passes through the front and back of the syringe body 1d and extends along the axis. In the following description, the front end opening 1a ₁ side with respect to the axial direction is referred to as the front end side, and the opposite side is referred to as the rear end side. In the illustrated example, the window holes 1f are arranged to face each other across the axis of the syringe 1, and a total of two window holes 1f are formed as shown in FIGS. The rear end of the opening end of the window hole 1f has a Madoanatan 1f ₁ to be described later. Further, a groove 1g is provided in a portion provided with the window hole 1f on the inner side of the syringe 1 from the periphery of the opening end on the front end side of the window hole 1f to the rear end of the syringe body 1d. The inner surface of the intermediate cylinder 1 b is substantially parallel along the axis of the syringe 1. An inclined portion 1c _{1 that} is inclined from the front end side toward the rear end side is provided on the inner surface of the step portion 1c.

A piston 2 is slidably disposed in the syringe 1. The piston 2 is made of a soft material (rubber or the like), and the contents filled inside the syringe 1 are liquid-tightly sealed together with a rod to be described later to form a filling space M filled with the contents. Yes. Note the filling space M here means the area inside the syringe 1 extending from the distal end opening 1a ₁ of the tip tube body 1a in front end wall 2a ₁ of the piston 2.

The piston 2 has a distal end portion 2a having a distal end wall 2a ₁ and having an outer diameter substantially the same as or slightly larger than the inner diameter of the intermediate cylinder 1b, and an inclined portion 2b inclined from the distal end side toward the rear end side. A base portion 2c that is integrally connected to the distal end portion 2a, and a central opening 2d that penetrates the distal end portion 2a and the base portion 2c along the axis are provided. Central aperture 2d is distal inner surface wall 2d ₁ located at the top side substantially parallel along the axis, at the rear end side through the inclined wall 2d ₂ inclined toward the rear side from the front end side The rear end inner wall 2d ₃ is connected. Further, the base portion 2c, the concave coupling portion 2c ₁ which connects the later-described plunger is provided.

Reference numeral 3 denotes a plunger connected to the piston 2. The plunger 3 includes a plunger body 3a extending along the axis. The distal end side of the plunger body 3a is convex engaging portion 3a ₁ integrally connected to the concave coupling portion 2c ₁ is formed. The inside of the plunger main body 3a extend through along the axis, thereby forming an inner space 3a _2. In the inner space 3a ₂ , the tip inner wall 3a ₃ located on the tip side has the same inner diameter as the rear end inner wall 2d ₃ of the piston 2, and the inclined wall 3a ₄ inclined from the tip side toward the rear end side is provided. And is connected to the rear end inner wall 3a ₅ located on the rear end side. An elastic piece 3a ₆ is provided outside the plunger body 3a so as to correspond to the window hole 1f of the syringe 1. The elastic pieces 3a ₆ are inclined so as to spread outward from the front end side toward the rear end side. The free end of the elastic piece 3a ₆ is a locking end 3a ₇ described later. Further, a rib 3a ₈ having substantially the same outer diameter as that of the base portion 2c is provided at a portion where the elastic piece 3a ₆ is provided so as to exclude a deflection displacement of the elastic piece 3a ₆ . Furthermore, the plunger 3 includes an annular body 3b that is integrally connected to the rear end portion of the plunger body 3a, and a flange (plunger stopper) 3c that extends radially outward from the rear end portion of the annular body 3b. . The flange 3c includes an annular wall 3c ₁ to a smaller diameter than the flange 3c protruding toward the rear end. The outer edge of the rear end of the annular wall 3c ₁ is inclined portion 3c ₂ is formed.

Moreover, it is preferable to arrange a cover 3d behind the plunger stopper 3c. The cover 3d is detachably attached to the plunger stopper 3c (for example, a screw connection or a connection by elastically moving claws). In the illustrated example, the plunger stopper 3c and the cover 3d are coupled via a hinge h. Cover 3d, the central wall portion with integrally connecting (plunger operating portion) wall 3d ₂ of the edge ring of 3d _1, the inside of the peripheral wall 3d _2, the ribs 3d of the height is lower than the peripheral wall 3d _{2 A} plurality of ₃ are provided at intervals in the circumferential direction. The outside of the peripheral wall 3d ₂ is integrally connected to the convex portion 3d ₄ at a position facing the hinge h. The peripheral wall 3d ₂ inner diameter substantially the same as the outer diameter of the annular wall 3c _1, or because it is slightly smaller, in the cover 3d is closed resulting position shown in FIG. 1 (cover mounting posture), the cover 3d is The annular wall 3c ₁ is held by fitting.

Reference numeral 4 denotes a rod that is arranged in the inner space 3 a ₂ of the plunger 3 and has a double concentric arrangement with the plunger 3. Rod 4, a central opening 2d of the piston 2, the tip in particular to be substantially the same, or has an outer diameter slightly larger, slidably held on the tip inner surface wall 2d ₁ and the tip inner surface wall 2d ₁ of the inner diameter An intermediate part 4a, an intermediate part 4c integrally connected to the front end part 4a via an inclined part 4b inclined from the front end side toward the rear end side, and an intermediate part via an inclined part 4d inclined from the front end side toward the rear end side 4c and a rod body 4e integrally connected to 4c. Also, there is substantially on the same plane with the front end wall 2a ₁ of the front wall 4a ₁ and the piston 2 of the tip portion 4a. Moreover, the hole part 4f as a stealing is formed in the inner side from the intermediate part 4c to the rod main-body part 4e, and the thickness of those parts is substantially the same. Further, a flange (rod operating portion) 4g extending radially outward is provided at the rear end portion of the rod body portion 4e, and an annular portion 4h toward the tip end side is formed at the edge of the rod operating portion 4g. Yes. Here the rod operating unit 4g, when providing the cover 3d, it is preferable to contact a central wall portion 3d ₁ of the inner surface of the cover 3d as shown in FIG. The end portion of the distal end side of the annular portion 4h has a rod stopper 4h _1. As will be described later, the rod stopper 4h ₁ abuts against the plunger 3 when the rod 4 is pushed in to stop the pushing, and the shape thereof is only at the end of the annular portion 4h on the tip side. For example, the surface of the rod operating portion 4g may be brought into direct contact with the plunger stopper 3c without providing the annular portion 4h.

  Reference numeral 5 denotes a distal end cover that is mounted on the distal end cylindrical body 1a of the syringe 1 in an unmounted posture of an injection needle that will be described later. The front end cover 5 is composed of a circular wall 5a and an annular peripheral wall 5b integrally connected to the edge of the circular wall 5a. The peripheral wall 5b is fitted into the front end cylindrical body 1a so as to liquid-tightly seal the filling space M. Can be stopped. The tip cover 5 may be attached to the tip cylinder 1a by screwing.

  In FIG. 4, reference numeral 6 denotes an injection needle attached to the distal end cylindrical body 1 a of the syringe 1 after removing the distal end cover 5. The injection needle 6 is stored in a protective case C or the like when not in use, for example. Various types of injection needles 6 can be used. In the illustrated example, the needle portion 6b is attached to the base portion 6a, and the base portion 6a is pushed into the distal end cylinder 1a so that the syringe 1 is inserted into the syringe 1. Installation is now complete. In addition, you may make it mount by providing a screw part in the base 6a and the front-end | tip cylindrical body 1a, and screwing together.

In the syringe configured as described above, when the piston 2 and the plunger 3 are attached to the syringe 1, the outer diameter of the tip 2a of the piston 2 is substantially the same as or slightly the inner diameter of the intermediate cylinder 1b of the syringe 1. Although larger, the tip portion 2a, since it is inserted guided by the inclined portion 1c ₁ of the syringe 1 in the intermediate cylindrical body 1b, never assembly workability is impaired. The plunger 3, the elastic pieces 3a ₆ presses along a groove 1g of the syringe 1, the plunger 3 is pushed distally while bending the elastic pieces 3a _6, locking end 3a ₇ is Madoanatan 1f _The elastic piece 3a _{6 that} has been bent when ₁ is exceeded is restored. Thereby, even if the plunger 3 is pulled back to the rear end side, the locking end 3a ₇ comes into contact with the window hole end 1f ₁ and the pullback amount of the syringe 1 is specified. The outer diameter of the distal end portion 4a of the rod 4 is substantially identical to the distal inner surface wall 2d ₁ having an inner diameter of the piston 2, or is slightly larger, but the tip portion 4a is guided by the inclined wall 2d ₂ of the piston 2 Since it is inserted into the tip inner wall 2d ₁ , the assembly workability is not impaired as with the syringe 1 and piston 2 described above.

  When discharging the contents with the above-mentioned syringe, the tip cover 5 is removed from the syringe in the non-injection posture shown in FIG. 4, and the injection needle 6 is attached as shown in FIG.

Then, as shown in FIG. 6, for example, in a state where the tip of the injection needle 6 is hidden in the contents accommodated in a bottle or the like, the plunger 3 is connected to the locking hole 3 a ₇ at the window hole end ₁ f ₁ . Pull back in the direction of the arrow until it touches. At this time, the outer diameter of the distal end portion 4a of the rod 4, so that almost the same or slightly larger and the tip inner surface wall 2d ₁ having an inner diameter of the piston 2, along with the retraction of the plunger 3, the rod as shown 4 is also pulled back. Thereby, since the inside of the filling space M becomes a negative pressure, the contents are sucked into the filling space M, and the plunger 3 is stopped at a predetermined pullback amount, so that the contents are not sucked up excessively. . Before the contents were sucked up, air was originally contained in the filling space M, so that when the contents were sucked up, the filling space M was in a state where air was also contained together with the contents.

Next, as shown in FIG. 7, in a posture in which the injection needle 6 is directed upward, the plunger operating portion 3d ₁ is pressed in the direction of the arrow, and the plunger 3 is slid along the axis along with the rod 4, and the plan The pressing is continued until the jar stopper 3c comes into contact with the finger hooking portion 1e of the syringe 1. Thereby, since the piston 2 is pushed toward the distal end cylindrical body 1 a of the syringe 1, the air in the filling space M and the injection needle 6 together with the contents is discharged from the distal end of the injection needle 6. Here, only a part of the contents to be discharged is present, and the contents remain in the filling space M. Incidentally, it rod 4 and the piston 2 Indian meal white (white tightening the tip portion 4a and the distal inner surface wall 2d ₁₎ is white tightening the piston 2 and the syringe 1 Indian meal white (tip part 2a and the intermediate cylinder 1b ), The cover 3d can be slid with the rod 4 even if it is pressed near the plunger stopper 3c of the plunger 3 with the cover 3d opened. If it closes and the plunger 3 is pressed, the rod 4 will not be pushed carelessly.

Thereafter, as shown in FIG. 8, the rod 4 can be pressed by opening the cover 3d. Since the cover 3d in the illustrated example is connected to the plunger stopper 3c at the hinge h, it is possible to open the cover 3d by one touch by pushing up over the fingers on the convex portion 3d _4.

Then, as shown in FIG. 9, the rod operating portion 4 g is pressed, and the tip portion 4 a of the rod 4 is protruded into the filling space M. And Continuing the push rod operating portion 4g, the rod stopper 4h ₁ abuts against the plunger stopper 3c, protrusion of the distal end portion 4a is stopped. Here, since the inside of the filling space M and the injection needle 6 is filled with the contents before the rod 4 is pushed in, the distal end portion 4a slides into the filling space M from the start of pushing the rod 4 until it stops. The content corresponding to the volume of the volume is discharged from the tip of the injection needle 6. Thereby, even if it is a small amount of contents, a predetermined amount can be discharged accurately.

Incidentally, when operating the generally syringe, in a state that served the index and middle fingers on the finger hook portion 1e of the syringe 1, pushes the plunger operating portion 3d ₁ with the thumb, but a plunger stopper 3c plunger operating portion 3d ₁ If the reaching length is too short, the retainability of the syringe may be impaired. Therefore, as shown in FIG. 10 corresponding to FIG. 5 described above, the rod body portion 4e and the cover 3d are extended to the rear end side (from the plunger stopper 3c shown in FIG. 10 to the plunger operating portion 3d ₁ It is possible to make it easier to hold.

  Further, as shown in FIG. 11 corresponding to FIG. 5 described above, the piston 2 and the plunger 3 are integrally connected to form a new plunger 30 made of, for example, a synthetic resin (in the figure, reference numerals of respective parts of the plunger 30). Is attached to correspond to the plunger 3), and an annular elastic member G (such as an O-ring) is disposed in a portion that slides between the syringe 1 and the inner side of the plunger 30. You may provide the groove | channel S and the elastic member G in the rod 4 which slides.

  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 Syringe 1a Tip cylinder 1b Intermediate cylinder 1c Step part 1d Syringe body 1e Flange (finger part)
1f window hole 1f ₁ window hole end 1g groove 2 piston 2a tip 2b inclined part 2c base 2d central opening 3 plunger 3a plunger main body 3a ₂ inner space 3a ₆ elastic piece 3a ₇ locking end 3b annular body 3c flange ( Plunger stopper)
3d cover 3d ₁ central wall (plunger operation part)
3d ₂ peripheral wall 3d ₃ rib 3d ₄ convex part 4 rod 4a tip part 4b inclined part 4c intermediate part 4d inclined part 4e rod body part 4f hole part 4g flange (rod operating part)
4h annular portion 4h ₁ rod stopper 5 tip cover 5a circular wall 5b peripheral wall 6 injection needle 6a base 6b needle portion M filling space

Claims (5)

A syringe having a tip cylinder for mounting an injection needle, a piston slidably disposed in the syringe and forming a filling space for contents inside the syringe, and coupled to the piston and pushing force A plunger for discharging the contents in the filling space from the tip of the injection needle by a slide accompanying the addition of
The piston has a central opening penetrating in the axial direction toward the filling space;
The plunger has an inner space connected to the central opening, and the tip end portion is always exposed to the filling space and is slidably held in the central opening. Provide a double-positioned rod,
On the outer side of the plunger, a locking end is formed to stop the pulling back of the plunger for introducing the contents into the filling space with a predetermined pulling back amount in association with a window hole end provided in the syringe,
When pushing the plunger that discharges residual air in the filling space together with a part of the contents to the rear end of the plunger, the pushing is stopped by contact with a finger hook provided at the rear end of the syringe. Forming a plunger stopper,
The rod, the tip protrudes into the filling space at pushing of the rod, the contents which by the contact between the plunger according to the protrusion of the tip portion is stopped at a predetermined projection amount A syringe having a rod stopper for stopping the discharge of the liquid at a predetermined amount.   The syringe according to claim 1, wherein the locking end is the other end of an elastic piece having one end connected to the plunger.   The syringe according to claim 1 or 2, wherein the plunger includes a detachable cover that contacts the rear end of the rod and slides the rod as the plunger is pushed.   The syringe according to claim 3, wherein the cover is connected to the plunger stopper via a hinge.   The syringe according to any one of claims 1 to 4, wherein the syringe includes a distal end cover attached to the distal end cylindrical body when the injection needle is not attached.

Images