JP3056735B1 - Syringe - Google Patents

Abstract

A syringe capable of injecting a content enclosed in an outer cylinder and effectively using the syringe is developed. SOLUTION: This syringe has an outer cylinder 2 and a plunger 3 inserted into the outer cylinder 2 to form a content enclosure in the outer cylinder 2. A syringe 1 having a chamber 5 and capable of introducing the gas 4 in the air chamber 5 into the content enclosing section. The content 1 remaining in the cannula portion by bursting the air chamber 5 and releasing the gas. Can be injected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a syringe using an enclosed liquid or viscous fluid (hereinafter, referred to as contents), and more particularly to a syringe suitable for a disposable syringe.

[0002]

2. Description of the Related Art In recent years, disposable syringes are widely used in medical fields such as dentistry due to hygiene problems and the like. Disposable syringes consist mainly of an outer cylinder and a plunger, which are plastic moldings, and the amount of liquid or viscous fluid used in a single treatment is placed in a content enclosure formed by inserting the plunger into the outer cylinder. The treatment material (contents) is enclosed and used, and then discarded. However, with a conventional syringe,
Usually, the contents existing in the cannula portion which is the tip of the outer cylinder cannot be injected. Therefore, the treatment material is discarded together with the syringe. Considering an increase in cost due to the use of extra contents and environmental pollution, which has recently become a problem, it is preferable that all the contents can be ejected or used.

[0003] Techniques for ejecting the contents of a cannula have been disclosed. JP-A-8-895
No. 15, JP-A-7-31011 discloses a syringe in which a tip of a plunger or a deformable push tip attached to the tip of the plunger projects into the cannula portion to push out the contents of the cannula portion. . However, even with these syringes, all the contents remaining in the cannula cannot be pushed out, and the contents are discarded with the contents remaining in the syringe.

[0004]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a syringe capable of more effectively injecting the contents in the contents enclosing section and reducing the remaining amount.

[0005]

Means for Solving the Problems To solve the above problems, the present invention provides the following syringe. That is,
The present invention is a syringe having an outer cylinder and a plunger inserted into the outer cylinder to form a content enclosure in the outer cylinder, the syringe having an air chamber in the content enclosure or an adjacent portion, The chamber provides a syringe configured to introduce gas from the air chamber into the contents enclosure. In this syringe, a syringe having the air chamber at the tip or inside of the plunger is also provided. Also, in this syringe,
A syringe having the air chamber divided into the inside of the plunger and the bottom of the outer cylinder is also provided. In any one of these syringes, a syringe in which the air chamber is formed so as to be breakable is also provided.

[0006] The syringe of the present invention has an air chamber in a content enclosing portion or an adjacent portion. When the gas in the air chamber is introduced into the contents enclosing section, the contents in the contents enclosing section are pressurized and ejected by the introduced gas, or are in a state where they can be ejected by a plunger or the like. Thereby, the contents in the contents enclosing portion are effectively ejected, and the remaining amount is reduced.

[0007]

Next, embodiments of the present invention will be described in detail. The syringe of the present invention has an air chamber in a content enclosure formed by an outer cylinder and a plunger or an adjacent portion, and is formed so that gas in the air chamber can be introduced into the content enclosure. . The air chamber may be provided in the content enclosure or a portion adjacent thereto. Examples of the portion where the air chamber is formed in the content enclosing portion include a tip portion of a plunger inserted into the outer cylinder, a bottom portion of the outer cylinder, an inner peripheral surface of the outer cylinder, and the like. In addition, examples of a portion where the air chamber is formed in a portion adjacent to the content enclosing portion include an outer portion of the cylindrical portion of the outer cylinder, an inside of the plunger, and the like. The air chamber is formed so that gas in the air chamber can be introduced into the content enclosure. The introduction is achieved by, for example, enabling the air chamber to be destroyed, allowing the gas to be injected without destroying the air chamber, and the like. When the air chamber is destroyed and the gas is introduced into the contents enclosure, an air chamber is attached to the lower end of the plunger, a syringe provided with a vulnerable portion in the air chamber, the lower end of the plunger or the air chamber in the plunger. And a syringe provided with a projection at the inside of the plunger or at the bottom of the outer cylinder, a syringe provided with an air chamber divided at the inside of the plunger and at the bottom of the outer cylinder, and provided with a projection inside the plunger. . Examples of the case where the air chamber is not broken include a syringe provided with a check valve on the surface of the air chamber, and a syringe formed so that gas in the air chamber provided outside the outer cylinder can be press-fitted by a plunger-like body or the like. it can. Hereinafter, some specific examples will be described with reference to the drawings.

(First Embodiment) A first embodiment is described as follows.
An air chamber for enclosing gas is provided at the lower end of the plunger, and the air chamber is depressed to rupture the air chamber and release the gas. is there. FIG. 1 is a schematic diagram of a cross section of a syringe according to the first embodiment, which has an outer cylinder 2, a plunger 3 for pushing out the contents 1, and an air chamber 5 in which gas 4 is sealed.

The outer cylinder 2 has a cylindrical portion 6 having a bottom portion 7 and a cannula portion 8 connected to the bottom portion 7.
The end of the cylindrical portion 6 opposite to the bottom 7 is open,
The plunger 3 is formed so that it can be inserted. In the present embodiment, the cannula portion 8 is bent so as to be separated from the axial direction of the cylindrical portion 6, but the shape of the cannula portion 8 may be any shape suitable for the application, and is not limited to this. do not do. In addition, as the cannula part 8, the cylindrical part 6
Alternatively, a separate component may be used. Such a component is formed so as to be connectable to a discharge port provided at the bottom 7 of the tubular portion 6. In addition, a finger collar 9 on which a finger can be put during use can be provided at the upper end of the tubular portion 6.

The plunger 3 has an outer shape that can be inserted into the cylindrical portion 6 of the outer cylinder 2 and has an extruding collar 11 at one end. The other end has an extruded portion 10 that seals the opening side of the tubular portion 6 when inserted into the tubular portion 6.
The extruded portion 10 has an outer diameter substantially equal to the inner diameter of the cylindrical portion 6. The plunger 3 is inserted into the cylindrical portion 6, and the opening side of the cylindrical portion 6 is sealed by the pushing portion 10, so that the space from the pushing portion 10 to the ejection port of the outer cylinder 2 is filled with the contents. It becomes an enclosure.

The air chamber 5 is a bag-like body having a hollow portion for containing the gas 4. In this embodiment, the air chamber 5
Is provided on the end face of the push-out portion 10 of the plunger 3. As a result, in this embodiment, the air chamber 5 is adjacent to the content enclosure. The air chamber 5 is formed of an elastomer or the like. In this embodiment, a weak portion 13 is provided on the air chamber end surface 12 in order to easily break the air chamber 5.

The weak portion 13 is a portion having the lowest strength in the air chamber, and is formed so that stress is easily concentrated when a load is applied. For example, the bag-shaped body is formed as a thin portion, a portion using a low-strength material, or a joining portion. In this embodiment, the weak part 1
Reference numeral 3 denotes a concave portion having a depth not penetrating the thickness of the wall of the bag-like body. For example, when forming an air chamber, the thickness of a part of the film is reduced, or the outer surface, the inner surface, or both surfaces are reduced. It is provided by shaving. Weak part 13
Is preferably smaller than the inner diameter of the portion where the cannula portion 8 and the bottom 7 of the outer cylinder 2 are joined. Also,
As shown in FIG. 2, it is preferable that both the inner surface and the outer surface of the air chamber 5 be shallowly cut to form a single character or a cross, so that the air chamber 5 can be more easily ruptured.

As a method for attaching the air chamber 5 to the extruding portion 10, any conventionally known method having a tensile strength capable of withstanding the tension between the air chamber 5 and the extruding portion 10 may be used. For example, there are bonding with an adhesive or the like, fitting in which a concave portion or a convex portion is provided in each of the air chamber 5 and the pushing section 10, and integral molding of the pushing section 10 and the air chamber 5, etc., but fitting or bonding is simple and preferable. .

The gas chamber 5 is filled with a gas 4 for pushing out the contents 1 remaining in the cannula portion 8. Gas 4
Does not change over long periods of storage, such as nitrogen,
Any gas may be used as long as it does not alter the air chamber body and does not easily react with the contents 1. All gases used in the following embodiments satisfy this condition. Further, it is preferable that the gas 4 sealed in the air chamber 5 has a volume equal to or larger than the volume of the cannula portion 8 under the atmospheric pressure, since all the contents 1 remaining in the cannula portion can be ejected.

Next, a method for ejecting the contents 1 using the syringe of the present embodiment will be described. As shown in FIG. 1, the contents 1 are transferred to the cylindrical portion 6 and the cannula portion 8 of the outer cylinder 2.
And attach the plunger 3. As a result, a state in which the content 1 is sealed in the content enclosing portion is formed at the same time when the content enclosing portion is formed. The contents 1 are pressed by the end face 12 of the air chamber 5 attached to the pushing part 10 by inserting the plunger 3 by putting a finger on the finger collar 9 of the outer cylinder 2 and the pushing collar 11 of the plunger 3. The contents 1 can be ejected from the ejection port of the cannula portion 8. When the plunger 3 is inserted and the air chamber end surface 12 reaches the bottom 7 of the tubular portion 6 as shown in FIG. 3, the contents 1 are left in the cannula portion 8. At this point, the plunger 3 is pressed strongly to compress the air chamber 5. The compressed air chamber 5 ruptures at the weak part 13 and the gas 4 is released. The contents 1 remaining in the cannula portion 8 are ejected at the moment when the air chamber 5 ruptures, or are ejected from the ejection port by inserting the plunger 3 which can be further inserted due to the rupture of the air chamber 5. You.

In particular, when the gas 4 has a volume exceeding the volume of the cannula portion 8, it becomes easy to eject the entire contents 1 from the cannula portion 8. FIG. 4 shows the state after insertion in this case. In the present embodiment, by providing an air chamber in a syringe similar to the conventional one to release gas,
The contents of the cannula can also be ejected, and the contents can be used effectively.

(Second Embodiment) In a second embodiment,
An air chamber for enclosing the gas is provided at the lower end of the plunger, and a projection for breaking the air chamber is provided on the bottom 7 of the outer cylinder 2, so that the air chamber can be more easily broken than in the first embodiment. It is a syringe. FIG. 5 is a schematic cross-sectional view of a syringe according to the second embodiment, which has the same outer cylinder 2 and plunger 3 as in the first embodiment, and an air chamber 21 in which gas 4 is sealed. The protrusion 22 is provided on the bottom 7 of the outer cylinder 2.

As in the case of the first embodiment, the outer cylinder 2 has a cannula portion 8 at the bottom 7 and the opposite end is open so that a finger collar 9 can be provided. The protrusion 22 is attached to the bottom 7 of the outer cylinder 2. As shown in FIG. 6, one or more protrusions 22 may be provided, as long as they can destroy the air chamber end face 23, regardless of the number and shape thereof. In order to break the air chamber 21 more easily, it is preferable to provide a U-shaped or triangular projection at the center of the bottom 7 of the outer cylinder 2 as shown in FIG. The protrusion 22 may be made of any material having chemical resistance, such as plastic or metal. However, since the same material as the outer cylinder 2 can be used, it can be integrally formed with the outer cylinder 2. preferable.

As in the first embodiment, the plunger 3 has an extruding collar 11 at one end and an extruding portion 1 at multiple ends.
It has 0. An air chamber 21 is attached to the push-out unit 10 in the same manner as in the first embodiment.

The air chamber 21 is a bag-like body having a hollow portion for containing the gas 4. The air chamber end face 12 may be any film-like material that does not allow the contents 1 and the gas 4 in the air chamber 5 to permeate and can be easily broken by being pressed against the projection 22. Other portions are made of an elastomer or the like. It is preferable to use the same material for the air chamber end face 23 and other portions, that is, the entire air chamber 21, since it is possible to integrally mold the material. The gas 4 sealed in the air chamber 21 is equal to the sum of the volume of the cylindrical portion where the contents 1 remain and the volume of the cannula portion 8 even when the plunger 3 is inserted due to the presence of the projection 22 under the atmospheric pressure. It is preferable to have an equal or larger volume because all the contents 1 remaining in the cannula portion can be ejected.

Next, a method of injecting the contents 1 using the syringe of the present embodiment will be described. As shown in FIG. 5, the contents 1 are put into the cylindrical portion 6 and the cannula portion 8 of the outer cylinder 2, the plunger 3 is attached, and the contents 1 are sealed in the contents sealing portion. When the plunger 3 is inserted by putting a finger on the finger collar 9 of the outer cylinder 2 and the pushing collar 11 of the plunger 3, the contents 1 are pressed by the air chamber end face 23 of the air chamber 21 attached to the pushing section 10. The contents 1 can be ejected from the ejection port of the cannula portion. When the air chamber end face 23 reaches the projection 22, the cannula portion 8
The content 1 remains inside and in the vicinity of the protrusion 22 of the tubular portion 6. Further, when the plunger 3 is inserted, the projection 22 breaks the air chamber end face 23 and the gas 4 is released. The contents 1 remaining on the cannula portion 8 and the projection 22 of the tubular portion 6 are ejected with the force of the air chamber 21 at the time of rupture, or the plunger 3 which can be further inserted by the rupture of the air chamber 5 is used. It is emitted from the injection port by further inserting.

In particular, when the gas 4 has a volume larger than the sum of the volume of the cylindrical portion where the contents 1 remain and the volume of the cannula portion 8 because the projection 22 exists even when the plunger 3 is inserted, It is easy to eject the entire contents 1 from the cannula portion 8. In the present embodiment, the projection 22 is newly provided on the syringe of the first embodiment, so that the air chamber 21 can be easily destroyed with a smaller force, and the cannula portion is released by releasing gas. Can be ejected, and the contents in the syringe can be effectively used.

(Third Embodiment) A third embodiment is as follows.
This is a syringe in which an inner plunger is provided inside the plunger, an air chamber is provided inside the plunger, and a projection is provided at the tip of the inner plunger. FIG. 7 is a schematic cross-sectional view of a syringe according to the third embodiment, which has an outer cylinder 2 and a plunger 31 for pushing out the contents 1, and an inner plunger 32 provided inside the plunger 31. .

The outer cylinder 2 has a cannula portion 8 at the bottom 7 of the cylindrical portion 6 as in the first embodiment,
A finger collar 9 on which a finger can be put during use can be provided at the upper end of the.

The plunger 31 has a hole including the axial center in the axial direction. A diaphragm 33 is provided at the lower end of the plunger 31 so as to close the hole. The diaphragm 33 may be any film-like material that does not transmit the contents 1 and the gas 4 and can be easily broken by the protrusions. When a highly viscous substance is used as the content 1, a film-like material having many pores that do not pass through the content 1 but allow gas to pass through may be used. In this case, it is not necessary to fill the gas 4 in advance, and the trouble of filling the gas into the air chamber can be omitted.

The inner plunger 32 has an outer shape that can be inserted into a hole provided in the plunger 31, and has an extruding collar 34 at one end. At the other end, plunger 3
It has an extruding portion that seals the upper end side of the plunger 31 when inserted into one of the holes. The extruded portion has substantially the same cross-sectional area as the hole formed in the plunger 31 in the same shape. When the plunger 31 and the inner plunger 32 are inserted at the same time, uniform pressure is likely to be applied and molding is easy. Therefore, as shown in FIG. 7, the shape of the hole of the plunger 31 and the inner plunger 32 is preferably cylindrical.

The inner plunger 32 is fixed so as to be inserted halfway into the hole of the plunger 31. Air chamber 3
5 is provided as a space formed by the lower end of the inner plunger 32, the inner wall of the plunger 31 not adjacent to the inner plunger 32, and the diaphragm 33. The air chamber 35 is filled with a gas 4 for pushing out the contents 1 remaining in the cannula portion 8. When the gas 4 sealed in the air chamber 35 has a volume equal to or larger than the volume of the cannula portion 8 under the atmospheric pressure, the cannula portion 8
This is preferable because all the remaining contents 1 can be ejected.

The plunger 31 and the inner plunger 32 can be fixed by inserting the plunger 31 and the inner plunger 32 in a fixed state until the lower end of the plunger 31 reaches the bottom 7 of the outer cylinder 2. After that, any method can be used as long as the fixing can be released and only the inner plunger 32 can be inserted. In the present embodiment,
The plunger 31 and the inner plunger 32 are fixed by removable studs 36. The stud 36 is provided at a position where the lower end of the plunger 31 does not prevent the bottom 7 of the outer cylinder 2 from reaching the bottom 7 when the plunger 31 and the inner plunger 32 are inserted in a fixed state. When the lower end of the plunger 31 reaches the bottom 7 of the outer cylinder 2, the stud 36 can be removed and only the inner plunger 32 can be inserted.

At the lower end of the inner plunger 32, the plunger 3
The projection 37 is mounted on one axis. The protrusion 37 is shorter than the length of the cannula portion 8 on the axis of the outer cylinder 2 and has a length that does not protrude from the lower end of the plunger 31 in a fixed state. The shape of the protrusion 37 may be any shape as long as the diaphragm 33 can be easily broken, but a sword-like shape as shown in FIG. 7 or a shape in which two sword-like protrusions are perpendicular to each other at the center is preferable.

Next, a method of injecting the contents 1 using the syringe of the present embodiment will be described. As shown in FIG. 7, the contents 1 are transferred to the cylindrical portion 6 and the cannula portion 8 of the outer cylinder 2.
, The plunger 31 is attached, and the content 1 is sealed in the content sealing portion. By simultaneously inserting the fixed plunger 31 and the fixed inner plunger 32 by putting a finger on the finger collar 9 of the outer cylinder 2 and the pushing collar 34 of the inner plunger 32, the contents 1 of the plunger 31 and the diaphragm 33 are formed.
Is pressed, and the contents 1 can be ejected from the ejection port of the cannula portion 8. When the lower end of the plunger 31 reaches the bottom 7 of the outer cylinder 2, the contents 1 remain in the cannula portion 8. At this time, when the studs 36 are removed, and the finger is pushed on the pushing collar 34 of the inner plunger 32 and only the inner plunger 32 is inserted, the protrusion 37 reaches the diaphragm 33 and breaks the diaphragm 33 and the gas 4 is discharged. Released. The contents 1 remaining in the cannula portion 8 are
5 or the air chamber 35
The inner plunger 32, which can be further inserted by the rupture of the inner plunger, is further ejected from the ejection port by further inserting.

In particular, when the gas 4 has a volume exceeding the volume of the cannula portion 8, it becomes easier to eject the entire contents 1 from the cannula portion 8. In this embodiment, the air chamber can be easily destroyed by attaching the projection, and the contents of the cannula can be ejected by releasing the gas, so that the contents in the syringe can be effectively used. Can be. Further, since the mounting position of the projection is at the lower end of the inner plunger, the possibility that the contents remain at the bottom of the outer cylinder is low.

(Fourth Embodiment) In a fourth embodiment,
This is a syringe in which an inner plunger is provided inside a plunger, a projection is provided at a tip of the inner plunger, and an air chamber is divided into the inside of the plunger and the bottom of an outer cylinder. FIG. 8 is a schematic cross-sectional view of a syringe according to the fourth embodiment, which includes an outer cylinder 2, a plunger 41, and an inner plunger 42 provided inside the plunger 41, as in the third embodiment.

The shapes of the plunger 41 and the inner plunger 42 are the same as the conditions in the third embodiment. The fixing method of the plunger 41 and the inner plunger 42 is as follows.
Any method that satisfies the following conditions may be used. First,
With the plunger 41 and the inner plunger 42 fixed,
This is a method in which the lower end of the plunger 41 can be inserted until it reaches the second air chamber 48, and then the fixing is released and only the inner plunger 42 can be inserted. Further, only the inner plunger 42 is inserted and the inner plunger 42 is inserted.
When the lower end of the plunger 41 is aligned with the lower end of the plunger 41, the plunger 41 and the inner plunger 42 are fixed again, and the plunger 41 and the inner plunger 42 can be inserted together. As such a method, the plunger is lengthened by applying the fixing method used in the third embodiment.
A method of providing a tack hole for inserting the removed tack once again at the upper end of the inner plunger may be considered.

In the present embodiment, as in the third embodiment, the lower end of the plunger 41 is fixed to the second air chamber 48 in a fixed state.
The plunger 41 and the inner plunger 42 are fixed by providing a detachable stud 43 at a position that does not prevent the plunger 41 from reaching the inner plunger. Further, the inner plunger 42 has an extrusion collar 4.
4, the length of the plunger 41 and the length from the lower end of the inner plunger 42 to just before the extrusion collar 44 are equal. The length of the plunger 41 is equal to or longer than the length of the outer cylinder 2. When the lower end of the plunger 41 reaches the second air chamber 48, the stud 43 can be removed and only the inner plunger 42 can be inserted. When the inner plunger 42 is inserted and the lower end of the inner plunger 42 is aligned with the lower end of the plunger 41, the upper end of the plunger 41 engages with the pushing collar 44 of the inner plunger 42. Can be inserted. This method is preferable because no device for re-fixation is required.

The lower end of the hole of the plunger 41 has a diaphragm 4
5 are provided. The diaphragm 45 may be any film-like material that does not transmit the contents 1 and the gas 4 and can be easily broken by the protrusions 46. When a highly viscous substance is used as the content 1, a film-like material having a large number of pores that does not transmit the content 1 but can transmit gas may be used. In this case, it is not necessary to fill the gas 4 in advance, and the trouble of filling the gas into the first air chamber 47 can be omitted.

A projection 46 is attached to the lower end of the inner plunger 42. The protrusion 46 is provided on the axis of the plunger 41 and has a length that does not protrude from the lower end of the plunger 41 in a fixed state. The projection 46 is the plunger 4
In order to prevent the inner plunger 1 and the inner plunger 42 from reaching the bottom 7 of the outer cylinder 2, the axial length of the projection 46 is preferably as short as possible. The shape of the protruding portion 46 may be any shape as long as the diaphragm 45 and the second air chamber 48 can be easily broken, but a plate-like blade longer than the inner diameter of the second air chamber 48 as shown in FIG. Is preferred.

The first air chamber 47 for enclosing the gas 4 has:
An end of the inner plunger 42, an inner wall of the plunger 41 not adjacent to the inner plunger 42, and a space formed by the diaphragm 45 are provided. A second air chamber 48 for enclosing the gas 4 is provided at the bottom 7 of the outer cylinder 2. The second air chamber 48 is provided in a ring shape along the inner wall of the cylindrical portion 6 so as not to prevent the contents 1 existing in the cylindrical portion 6 from flowing into the cannula portion 8. The second air chamber 48 may be formed entirely of a film-like material, or the cylindrical portion 6 of the outer cylinder 2.
May be a space formed by the inner wall and the bottom 7 and the film. The material of the film is the contents 1 and the second air chamber 48.
Any film-like material that does not permeate the gas 4 therein and can be easily broken by pressing the protrusion 46 may be used.
However, the material must be a material or an installation method that does not hinder the insertion of the plunger 41 after being broken by the protrusion 46. Therefore, the installation method in which the film-like material is peeled off from the inner wall of the cylindrical portion 6 of the outer cylinder 2 by inserting the plunger 42, and the sufficiently flexible enough that the plunger 41 can be inserted over the broken second air chamber 48. With a thin film,
preferable.

If the sum of the volume of the gas 4 sealed in the first chamber 47 and the volume of the gas 4 sealed in the second chamber 48 is equal to or larger than the volume of the cannula portion 8, the cannula portion 8 This is preferable because all remaining contents 1 can be ejected. The height of the first air chamber 47 is set to
The gas 4 is mainly longer than the second air chamber 48.
It is preferable to be enclosed in.

Next, a method of injecting the contents 1 using the syringe of the present embodiment will be described. As shown in FIG. 8, the contents 1 are transferred to the cylindrical portion 6 and the cannula portion 8 of the outer cylinder 2.
, The plunger 41 is attached, and the content 1 is sealed in the content sealing portion. Put a finger on the extrusion collar 44 of the inner plunger 42 and put the plunger 41 and the inner plunger 42 together.
Is inserted, the contents 1 are pressed by the plunger 41 and the diaphragm 45, and the contents 1 can be ejected from the ejection opening of the cannula portion 8. When the lower end of the plunger 41 reaches the second air chamber 48, the contents 1 remain in the cannula portion 8 and inside the second air chamber 48. At this point, the tack 43 is removed and the inner plunger 42 is removed.
When the finger is further inserted into the pushing collar 44, the inner plunger 42 alone is inserted, and the projection 46 reaches the diaphragm 45 to break the diaphragm 45, and the gas 4 in the first air chamber 47 is released. discharge. Immediately thereafter, the protrusion 46 is moved to the second air chamber 4.
8, the second air chamber 48 is destroyed, and the gas 4 in the second air chamber 48 is released. The contents 1 remaining in the cannula portion 8 and inside the second air chamber 48 are the first air chamber 47 and the second air chamber 47.
Ejected at the moment of burst of the air chamber 48, or
The inner plunger 42 and the plunger 41, which can be further inserted due to the destruction of the air chamber 47 and the second air chamber 48, are further inserted from the injection port. When the lower end of the inner plunger 42 is aligned with the lower end of the plunger 41,
The plunger 4 is inserted into the extrusion flange 44 of the inner plunger 42.
Since the upper end of the inner plunger 1 is hooked, if a finger is pressed on the pushing collar 44 of the inner plunger 42, the plunger 41 and the inner plunger 44 can be inserted at the same time.

In particular, when the volume of the gas 4 sealed in the first air chamber 47 and the second air chamber 48 has a volume larger than the volume of the cannula portion 8, the entire contents 1 are ejected from the cannula portion 8. It becomes easier. In the present embodiment, the air chamber can be easily broken by attaching the projection to the lower end of the inner plunger, and the contents of the cannula can be ejected by discharging gas, and the contents in the syringe can be discharged. Can be used effectively. In addition, since the first air chamber is small and the length of the projection 46 is short by dividing the air chamber, the combined length of the fixed plunger and the inner plunger is short, and the operation is easy.

(Fifth Embodiment) In the fifth embodiment,
This is a syringe in which an inner plunger is provided inside the plunger, and a check valve is provided in a diaphragm stretched at the lower end of the plunger. FIG. 9 is a schematic diagram of a cross section of a syringe according to the fifth embodiment, and illustrates an outer cylinder 2, a plunger 51, and a plunger 51.
And an inner plunger 52 provided inside the inside.

The plunger 51 has a hole including the axial center in the axial direction. A diaphragm 53 is provided at the lower end of the plunger 51 so as to close the hole. The diaphragm 53 may be any film-like material that does not transmit the contents 1 and the gas 4 and can be easily broken by the protrusions.

The diaphragm 53 is provided with a check valve 54 which is opened by receiving pressure from the inside of the plunger 51. As shown in FIG. 10, the check valve 54 has a smaller diameter on the axis of the plunger 51 than the inner diameter of a portion where the bottom 7 of the outer cylinder 2 and the cannula portion 8 are joined. The material of the check valve 54 may be any material that does not allow the contents 1 and the gas 4 to permeate and that can maintain airtightness when the check valve 54 is closed. It is preferable to use the same material for the diaphragm 53 and the check valve 54 because they can be integrally formed.

The inner plunger 52 has an outer shape that can be inserted into a hole provided in the plunger 51, and has an extrusion flange 55 at one end. At the other end, a plunger 5
It has an extruded portion that seals the upper end side of the plunger 51 when inserted into one of the holes. The extruded portion has substantially the same cross-sectional area as the hole formed in the plunger 31 in the same shape. When the plunger 51 and the inner plunger 52 are inserted at the same time, uniform pressure is likely to be applied and molding is easy. Therefore, the shape of the hole of the plunger 51 and the inner plunger 52 are preferably cylindrical.

The inner plunger 52 is fixed so as to be inserted halfway into the hole of the plunger 51. The plunger 51 and the inner plunger 52 can be fixed by inserting the plunger 51 and the inner plunger 52 until the lower end of the plunger 51 reaches the bottom 7 of the outer cylinder 2 with the plunger 51 and the inner plunger 52 fixed. Any method can be used as long as it can be released and only the inner plunger 52 can be inserted. In the present embodiment, two grooves 56 are provided in the plunger 51 as shown in FIG.
2, two stoppers 57 are provided to fix the plunger 51 and the inner plunger 52. The two stoppers 57 of the inner plunger 52 are located in the middle of the axis of the inner plunger 52 and are opposed in the radial direction. The inner diameter of the inner plunger 52 at the stopper portion is smaller than the inner diameter of the cylindrical portion 6 of the outer cylinder 2. . The two grooves 56 of the plunger 51 have a width larger than the width of the stopper 57, as shown in FIG. 11, and are provided so as to face the upper end of the plunger 51 in the radial direction. The depth of the groove 56 is determined by the stopper 57 when the lower end of the plunger 51 reaches the bottom 7 of the outer cylinder 2.
When the inner plunger 52 alone is inserted into the outer cylinder 2 through the groove 56, the depth is such that the tip of the inner plunger 52 can reach the bottom 7 of the outer cylinder 2. At first, stopper 57 is groove 56
When the push-out collar 55 of the inner plunger 52 is pushed so as not to pass through, the stopper 57 is engaged with the upper end of the plunger 51, so that the plunger 51 and the inner plunger 52 are inserted at the same time. When the lower end of the plunger 51 reaches the bottom 7 of the outer cylinder 2, the stopper 57
Can be inserted into the groove 56 so that only the inner plunger 52 can be inserted. When the plunger 51 and the inner plunger 52 are fixed by this method, no new parts are required for fixing, the method of use is simple, and the cost is low, which is preferable.

The air chamber 58 has a lower end portion of the inner plunger 52,
An inner wall of the plunger 51 not adjacent to the inner plunger 52,
And a space formed by the diaphragm 53. A gas 4 for pushing out the contents 1 remaining in the cannula portion 8 is sealed in the air chamber 35 at a pressure slightly lower than the atmospheric pressure. The gas 4 sealed in the air chamber 58 is
It is preferable to have a volume equal to or larger than the volume of the cannula portion 8 under the atmospheric pressure because all the contents 1 remaining in the cannula portion 8 can be ejected.

Next, a method of injecting the contents 1 using the syringe of the present embodiment will be described. As shown in FIG. 7, the contents 1 are transferred to the cylindrical portion 6 and the cannula portion 8 of the outer cylinder 2.
, The plunger 51 is attached, and the content 1 is sealed in the content sealing portion. Put a finger on the extrusion flange 55 of the inner plunger 52 and put the plunger 51 and the inner plunger 52 together.
Is inserted, the contents 1 are pressed by the plunger 51 and the diaphragm 53, and the contents 1 can be ejected from the ejection opening of the cannula portion 8. When the lower end of the plunger 51 reaches the bottom 7 of the outer cylinder 2, the content 1 remains in the cannula portion 8. At this time, when the inner plunger 52 is rotated to align the stopper 57 with the groove 56 and further inserted by putting a finger on the pushing flange 55 of the inner plunger 52, only the inner plunger 52 is inserted. While the inner plunger 52 is being inserted, the check valve 5
4 is released under pressure, so that the gas 4 can be released and the contents 1 remaining in the cannula portion 8 can be ejected.

When the volume of the gas 4 sealed in the air chamber 58 has the same or larger volume as that of the cannula portion 8, it becomes easy to eject the entire contents 1 from the cannula portion 8. In the present embodiment, the use of the check valve as the air chamber opening means allows the gas to be easily released even without the projection, and ejects the contents of the cannula portion to thereby release the contents in the syringe. Things can be used effectively. In addition, since it is not necessary to provide a projection, the structure of the syringe becomes simpler, which is preferable.

Although not described in the present embodiment,
Since the air chamber only needs to be adjacent to the contents enclosing section, in addition to providing the air chamber inside the outer cylinder as in the above embodiment, the outer cylinder such as outside the outer cylinder or in the outer cylinder when ejecting the contents is also used. It is also possible to provide an air chamber so as to be installed in a place other than the inside. For example, it is conceivable that a syringe in which gas is newly sealed in a content sealing portion is attached to a cylindrical portion near the bottom of the outer cylinder to form an air chamber.

[0050]

According to the present invention, it is possible to provide a syringe capable of more effectively injecting the contents in the contents enclosing portion and reducing the remaining amount.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state in which contents are sealed in a syringe using an air chamber according to a first embodiment of the present invention.

FIGS. 2 (a) and 2 (b) are each a combination of a view of the weak portion provided on the end face of the air chamber of the syringe of FIG. 1 viewed from the plunger insertion direction and a cross-sectional view.

FIG. 3 is a cross-sectional view showing a state in which a plunger is inserted and an end surface of an air chamber reaches a bottom of an outer cylinder with the syringe of FIG. 1;

FIG. 4 is a cross-sectional view showing a state in which all the contents are injected by the syringe of FIG. 1;

FIG. 5 is a sectional view showing a state in which contents are sealed in a syringe according to a second embodiment of the present invention.

6 (a), 6 (b) and 6 (c) show another example of a projection provided on the bottom of the outer cylinder of the syringe of FIG. 5, respectively, and are a view and a cross section viewed from the plunger insertion direction. It is the figure which combined the figure.

FIG. 7 is a cross-sectional view showing a state in which contents are sealed in a syringe according to a third embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a state in which contents are sealed in a syringe according to a fourth embodiment of the present invention.

FIG. 9 is a cross-sectional view showing a state in which contents are sealed in a syringe according to a fifth embodiment of the present invention.

FIG. 10 is a sectional view of a diaphragm and a check valve of the syringe of FIG. 9;

FIG. 11 is a perspective view of a plunger of the syringe of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Contents 2 Outer cylinder 3 Plunger 4 Gas 5 Air chamber 6 Cylindrical part 7 Bottom part 8 Cannula part 10 Finger collar 11 Extrusion part 13 Extrusion collar 14 Air chamber end face 15 Vulnerable part 21 Air chamber 22 Projection part 23 Air chamber end face 31 Plunger 32 Inner Plunger 33 Separator 34 Extrusion Collar 35 Air Chamber 36 Tack 37 Projection 41 Plunger 42 Inner Plunger 43 Tack 44 Extrusion Collar 45 Separator 46 Projection 47 First Air Chamber 48 Second Air Chamber 51 Plunger 52 Inner Plunger 53 Diaphragm 54 Check valve 55 Extrusion flange 56 Groove 57 Stopper 58 Air chamber

Claims (4)

(57) [Claims] 1. A syringe having an outer cylinder and a plunger inserted into the outer cylinder to form a content enclosure in the outer cylinder, the syringe having an air chamber in the content enclosure or an adjacent portion. And a syringe formed so that gas in the air chamber can be introduced into the content enclosure. 2. The syringe according to claim 1, wherein the air chamber is provided at a tip portion or inside the plunger. 3. The syringe according to claim 1, wherein an air chamber is divided into an inside of the plunger and a bottom of the outer cylinder. 4. The syringe according to claim 1, wherein the air chamber is formed so as to be breakable.