JP3422367B2 - Medical device fluid check valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid check valve for medical devices such as infusion sets.

[0002]

2. Description of the Related Art Medical devices such as an infusion set for injecting a drug into a living body are known. The infusion set includes, for example, an infusion container containing a drug and the like, and a spike needle that punctures a sealed rubber stopper provided in the infusion container to withdraw the drug. The spike needle is provided with a liquid passage therein, and a tube or the like for administering a drug or the like into the living body is connected to the liquid passage. In the infusion set, usually, the infusion container is installed at a height of 70 cm from the infusion site, and the drug or the like is instilled into the living body through the spike needle due to the pressure drop between the infusion container and the infusion site. It is to be administered.

In the infusion set, when the infusion container is made of a hard material such as glass and the drip is continued in a sealed state, the infusion container maintains its shape against the external pressure, so that the infusion container is maintained. The inside becomes negative pressure and the drip stops. Therefore, separately, by puncturing the infusion container with a ventilation needle or providing the spike needle with a ventilation structure to introduce the atmosphere into the container, the atmospheric pressure in the infusion container is made equal to the external pressure, Prevent negative pressure in the container.

For example, the conventional spike needle 31 shown in FIG.
Is provided with a liquid passage 3 inside the sharp tip portion 2,
An air passage 4 parallel to the liquid passage 3 is provided, and the liquid passage 3 and the air passage 4 are provided.
And are both open to the tip 2. A side tube 5 is provided at the other end of the air passage 4, and the air passage 4 is exposed to the outside air through a communication hole 7 provided at the bottom of a bottomed tubular intermediate body 6 fitted to the side tube 5. I am in touch. A hydrophobic porous filter 8 is attached to the open end of the intermediate body 6.

The porous filter 8 has air permeability and does not prevent the permeation of outside air. However, since it is hydrophobic, it does not permeate the drug or the like flowing back from the infusion container into the air passage 4,
Leakage of the drug or the like can be prevented.

By the way, when instilling a drug or the like with the infusion set, it is rare that only one type of drug is used, and in many cases, a large number of drugs are mixed and infused into the infusion container according to a doctor's prescription. Is administered. The mixed injection is performed by puncturing a sealed rubber stopper provided in the infusion container with an injection needle and injecting another drug into the infusion container with a syringe. However, in this case, when the infusion container is a hard container such as glass, the internal pressure of the infusion container becomes higher than the atmospheric pressure. When the internal pressure of the infusion container exceeds the pressure resistance limit of the porous filter 8, there is a problem that the drug or the like easily leaks from the porous filter 8. In addition, the porous filter 8
Even if the agent does not leak, the component in the drug that has precipitated when the drug or the like comes into contact with the drug may be adsorbed to the pores to cause clogging, and the predetermined ventilation performance may not be obtained.

Therefore, in order to solve the above problems of the porous filter 8, it has been proposed to provide a valve element in the side pipe 5 on the downstream side of the porous filter 8.

The spike needle 41 shown in FIG. 4 is an example in which a check valve 42 made of a rubber elastic body is provided in the side tube 5. In the spike needle 41 shown in FIG. 4, the check valve 42 made of a rubber elastic body has a slit portion (not shown) on the mountain-shaped top portion 43, and when the external pressure is applied, the slit portion opens to allow outside air to flow from the side pipe 5 to the ventilation passage. It is introduced into the infusion container via 4. Further, when the drug or the like in the infusion container flows back, the pressure causes the slit portion to close, thereby preventing the drug or the like from leaking.

Further, the spike needle 51 shown in FIG.
Check valve 5 with the tip of thermoplastic tube processed inside
This is an example in which 2 is provided. The check valve 52 has a tube made of a thermoplastic material whose end is processed into a hemispherical shape and is sealed, and a slit portion (not shown) is formed on the hemispherical top portion 53. As with the spike needle 41 shown in FIG. 4, the spike needle 51 shown in FIG. 5 opens the slit portion when external pressure is applied, so that the outside air is introduced into the infusion container from the side tube 5 through the ventilation passage 4, When the drug or the like in the infusion container flows back, the pressure closes the slit portion to prevent the drug or the like from leaking.

The check valves 42 and 52 prevent the chemicals and the like from flowing into the porous filter 8 when the chemicals and the like in the infusion container flow back. It is also possible to prevent contact with the porous filter 8 and maintain the ventilation performance of the porous filter 8.

However, the check valves 42 and 52 are
There is an inconvenience that the design is restricted due to the need for a space to be installed inside the side pipe 5. Further, the check valves 42 and 52 must separately be processed from a tube made of a rubber elastic body or a thermoplastic material, which inevitably leads to an increase in cost.

Instead of the check valves 42 and 52, a check valve using a metal ball, a diaphragm valve using a rubber elastic body, a valve for opening and closing a rubber plate like a hand pump to be opened like a door, and the like are also considered. Although these valves can cope with a sudden change in pressure, it is difficult to cope with the static pressure such that the drug or the like gradually exudes by contacting the valve, and the leakage of the drug or the like is sufficiently prevented. There is an inconvenience that it cannot be prevented.

[0013]

DISCLOSURE OF THE INVENTION The present invention solves such inconveniences and prevents the liquid in the liquid container from leaking from the ventilation passage with a simple structure, and is an inexpensive fluid for medical devices. The purpose is to provide a check valve.

[0014]

In order to achieve the above object, a fluid check valve of a medical device according to the present invention comprises a vent passage for supplying outside air to a liquid container for supplying liquid to the outside via a liquid passage. A check valve for preventing liquid in the liquid container from leaking from the ventilation passage, the communication hole connecting the ventilation passage and the outside air, and the communication hole on the ventilation passage side of the communication hole. A valve seat formed of a recessed portion surrounding the communication hole, a sheet-shaped valve body disposed in the recessed portion, and a sheet-shaped valve body protruding from the air passage side into the recessed portion so that the sheet-shaped valve body is removed from the recessed portion The sheet-like body is composed of a protrusion serving as a support member that is supported so as not to be separated, and the sheet-shaped member is movable in a space between the bottom surface of the recess and the protrusion, When the liquid in the liquid flows backward, the liquid comes into close contact with the bottom surface of the recess and closes the communication hole, so that the inside of the liquid container has a negative pressure. Wherein the peeled from the bottom surface of the concave portion moves to the protrusion portion side becomes.

In the check valve of the present invention, the sheet-shaped valve element disposed in the valve seat formed of the recess is movable in the space between the bottom surface of the recess and the projection. When the liquid in the liquid container flows back to the ventilation passage, the sheet-shaped valve body is brought into close contact with the bottom surface of the recess to close the communication hole and prevent the liquid from leaking. Further, the sheet-shaped valve body is separated from the bottom surface of the recess by the external pressure when the air pressure side becomes negative and the outside air enters the communication hole, and the sheet-shaped valve body and the bottom surface of the recessed portion. The outside air can be introduced into the ventilation passage through the gap between and. When the sheet-shaped valve element is peeled from the bottom surface of the recess, the sheet-shaped valve element is held in the recess and prevented from being detached from the recess because it is supported by the protrusion.

Since the sheet-shaped valve body is movable in the space between the bottom surface of the concave portion and the protruding portion as described above, it is sensitive to static pressure as well as sudden changes in pressure. Therefore, the liquid can be reliably prevented from leaking.

Further, according to the above construction, it is sufficient that the sheet-like valve body has a volume capable of moving between the bottom surface of the recess and the protrusion in the recess, which reduces design restrictions. be able to. The sheet-shaped valve body can be used by punching out or cutting out a synthetic resin film or the like having a self-supporting property. The synthetic resin film may be produced by any method such as extrusion molding, stretch molding, and roll molding, and the cost can be reduced by using a general-purpose film such as a packaging material.

In the check valve of the present invention, an adhesive layer is provided on the bottom surface of the recess so as to improve the adhesion and pressure resistance of the sheet-shaped valve body and to repeat the adhesion and peeling as many times as desired. It is characterized by being provided. The pressure-sensitive adhesive layer can be formed, for example, by applying silicone oil.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 is an explanatory cross-sectional view showing one structural example of a fluid check valve of a medical device of the present invention, and FIG. 2 is an operation explanatory view showing an enlarged main part of FIG.

The fluid check valve of this embodiment is used for a spike needle that is punctured in an infusion container of an infusion set. As shown in FIG. 1, the spike needle 1 includes a sharp tip portion 2 that is pierced by a sealed rubber stopper of an infusion container (not shown),
A liquid passage 3 is provided inside for injecting a liquid such as a drug contained in the infusion container into a living body through a rubber tube or the like. An air passage 4 parallel to the liquid passage 3 is provided inside the spike needle 1, and both the liquid passage 3 and the air passage 4 are open at the tip 2.

At the other end of the air passage 4, a side tube 5 orthogonal to the air passage 4 is provided, and the air passage 4 is provided at the bottom of a bottomed cylindrical intermediate body 6 fitted in the side tube 5. The outside air is communicated through the communication hole 7. The intermediate body 6 is locked to the end portion of the side pipe 5 by a flange 6a provided at the opening end portion, and the depth at which the intermediate body 6 is fitted into the side pipe 5 is regulated. The porous filter 8 is attached to the outside of the flange 6a.

On the other hand, on the air passage 4 side of the intermediate body 6, a recess 9 as a valve seat is provided surrounding the opening of the communication hole 7, and the seat 9 is provided in the recess 9. ing. A projection 11 is formed in the air passage 4 so as to face the communication hole 7 and projects into the recess 9. The valve body 10 is movable in the space between the bottom surface 9a of the recess 9 and the projection 11. The check valve of the present embodiment is formed by the recess 9, the valve body 10, and the protrusion 11.

The side tube 5 is provided with a through hole 12 for the lid 1.
3, the porous filter 8 is sandwiched between the flange 6 a of the intermediate body 6 and the lid 13. When the spike needle 1 is punctured in a flexible infusion container such as an infusion bag made of a soft synthetic resin and the internal pressure of the infusion container does not need to be kept equal to the external atmospheric pressure, the through hole 12 is covered with a dedicated cap or the like. Is blocked.

Next, the operation of the check valve of this embodiment will be described with reference to FIG.

First, when the spike needle 1 is punctured in the hermetically sealed rubber stopper of the infusion container to infuse the liquid, the inside of the infusion container has a negative pressure in a normal state.
Has peeled off from the bottom surface 9a of the recess 9 and has moved to the side of the protrusion 11. At this time, the protrusion 11 acts as a support that supports the valve body 10 so as not to separate from the recess 9 that is the valve seat.

In the above state, the outside air is the porous filter 8
After the dust or the like is removed by, the air passes through the communication hole 7 through the gap between the bottom surface 9a of the recess 9 and the valve body 10 to the ventilation path 4, and is introduced from the ventilation path 4 into the infusion container. As a result, the atmospheric pressure in the infusion container is maintained equal to the external atmospheric pressure, and the drug or the like in the infusion container is administered from the liquid passage 3 into the living body.

Next, when another drug is mixed and injected into the infusion container so that the air pressure in the infusion container becomes higher than the external pressure, the drug or the like in the infusion container flows back to the ventilation passage 4. At this time, the valve body 10 is sensitive to the pressure at which the drug or the like flows backward, and as shown in phantom in FIG.
Adhere to a. As a result, it is possible to prevent the communication hole 7 from being blocked by the valve body 10 and leaking the drug or the like to the outside.

The valve body 10 is polyolefin-based, since it is not toxic to living organisms and inactive to drugs.
A synthetic resin film having self-supporting properties such as polycellulose, polyvinyl chloride, polyethylene terephthalate, polystyrene, and fluororesin is suitable. The synthetic resin film preferably has a thickness of 15 to 200 μm. The thickness of the synthetic resin film is 15 μm
When the value is less than the above value, it becomes difficult to prevent leakage of the drug or the like flowing back when the valve body 10 comes into close contact with the bottom surface 9a of the recess 9 and closes the communication hole 7. If the thickness of the synthetic resin film exceeds 200 μm, the ventilation passage 4
When the side becomes negative pressure and external pressure is applied to the valve body 10, the valve body 10 may not be separated from the bottom surface 9a of the recess 9 due to the hardness of the film itself. When the check valve is used for the spike needle 1 of the infusion set as in the present embodiment, the thickness of the synthetic resin film is 20 to 20 so that the valve body 10 can operate with a high sensitivity even with a drop pressure of about 60 cm. 7
It is preferably 0 μm.

Further, the specific gravity of the synthetic resin film is preferably 2.4 or less, more preferably 1.0 or less, in order to exhibit a quick opening / closing operation with high sensitivity.

The synthetic resin film may be manufactured by any manufacturing method such as extrusion molding, stretch molding, and rolling molding, and a general-purpose film such as a packaging material can be used. The synthetic resin film can easily adjust the shape of the valve body 10 by punching or cutting it out, and no special equipment is required for processing the valve body 10, thus reducing the manufacturing cost. You can

The projection 11 contacts the valve body 10 so that the valve body 10 quickly separates from the tip of the projection 11 and comes into close contact with the bottom surface 9a of the recess 9 when the drug or the like flows backward. The area is preferably as small as possible. Due to the above action, in the present embodiment, the protrusion 1
Although the tip of No. 1 is formed in a hemispherical shape, the shape of the protrusion 11 is not limited to this as long as the above-mentioned action can be obtained, and may be, for example, a rib shape.

Further, on the bottom surface 9a of the concave portion 9, an adhesive agent (not shown) is provided so that the adhesion of the valve body 10 and the pressure resistance against the drug flowing back can be improved and the adhesion and the peeling can be repeated any number of times. Layers are provided. The adhesive layer is formed by applying an appropriate adhesive to the bottom surface 9a.

Silicone oil, for example, is suitable as the pressure-sensitive adhesive because it is not toxic to living organisms and is inactive to drugs. The silicone oil has a viscosity of 1 so that it can be applied uniformly without dripping on the bottom surface 9a.
It is preferably in the range of 000 to 100,000 cps, and more preferably in the range of 10,000 to 100,000 cps so that the valve body 10 can be closely adhered to and separated from the bottom surface 9a.

In the present embodiment, an example in which the check valve is applied to the spike needle 1 of the infusion set has been described. However, the present invention prevents the back flow of the liquid in the liquid container while preventing the back flow of the liquid in the liquid container. It can also be applied to other medical devices that require the introduction of gas.

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional view showing one structural example of a fluid check valve of a medical device according to the present invention.

FIG. 2 is an operation explanatory view showing an enlarged main part of FIG.

FIG. 3 is an explanatory cross-sectional view showing a configuration example of a fluid check valve of a conventional medical device.

FIG. 4 is an explanatory cross-sectional view showing another configuration example of the fluid check valve of the conventional medical device.

FIG. 5 is an explanatory cross-sectional view showing still another configuration example of the fluid check valve of the conventional medical device.

[Explanation of symbols]

4 ... Ventilation path, 7 ... Communication hole, 9 ... Valve seat, 9a ... Bottom surface, 10 ... Sheet-shaped valve body, 11 ... Support body.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) A61M 5/162 A61M 39/00-39/28

Claims (3)

(57) [Claims] 1. A check valve provided in a ventilation passage for supplying outside air to a liquid container for supplying liquid to the outside via a passage, and for preventing the liquid in the liquid container from leaking from the ventilation passage. And a valve comprising a communication hole that connects the ventilation path and the outside air, and a recessed portion that is provided on the ventilation path side of the communication hole so as to surround the communication hole.
A seat, and disposed a sheet-like valve body recess, protrudes from the vent roadside in the recess, the sheet-like valve body recess
With a protrusion as a support that supports it so that it does not detach from the
The sheet-shaped body is composed of a space between the bottom surface of the recess and the protrusion.
Is movable, and the liquid in the liquid container is
When it flows backward, it adheres to the bottom of the recess and closes the communication hole.
Then, when the inside of the liquid container becomes a negative pressure, it peels from the bottom of the recess.
And a fluid check valve for a medical device, wherein the fluid check valve moves toward the protrusion . 2. The fluid check valve for a medical device according to claim 1, wherein the sheet-shaped valve body is made of a synthetic resin film having a self-supporting property. 3. The fluid check valve for a medical device according to claim 1, wherein an adhesive layer is provided on the bottom surface of the recess .