JP2001087385A - Hydraulic check valve for medical equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cheap hydraulic check valve for medical equipment by which liquid in a liquid container can be prevented from leaking from a ventilation passage with a simple structure. SOLUTION: This valve is provided on a ventilation passage 4 for supplying the outside air to a liquid container, in order to prevent the liquid in the liquid container 4 from leaking. In this valve, a communication hole 7 for communicating the ventilation hole 7 and the outside air and a valve seat 9 provided on the communication hole 7 side so as to surround the communication hole 7 are provided. The valve is also provided with a sheet-like valve body 10 which is provided peelably freely on the bottom surface 9a of the valve seat 9 and is bonded on the bottom surface 9a of the valve seat 9 when the liquid flows backward and peels off from the bottom surface 9a of the valve 9 when the ventilation passage side 4 becomes at negative pressure and the outside air enters the communication hole 7, and a supporting body 11 for supporting the sheet-like valve body 10 which is provided so as to protrude from the ventilation passage 4 side into the valve 9 and is peeled off form the bottom surface 9a of the valve seat 9. The sheet-like valve body 10 is made of a synthetic resin having a self-supporting characteristic. An adhesive layer is provided on the bottom 9a of the valve seat 9.

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 a medical device such as an infusion set.

[0002]

2. Description of the Related Art Medical devices such as an infusion set for injecting a drug or the like into a living body are known. The infusion set includes, for example, an infusion container containing a medicine and the like, and a spike needle pierced by a sealed rubber stopper provided in the infusion container to lead out the medicine. The spike needle has a liquid passage therein, and a tube or the like for administering a drug or the like into a living body is connected to the liquid passage. The infusion set is usually installed at a height of 70 cm from the infusion container from the infusion site, via the spike needle, by instilling the drug or the like in the living body by the pressure drop between the infusion container and the infusion site. To be administered.

[0003] In the infusion set, when the infusion container is made of a hard material such as glass, if the infusion is continued in a sealed state, the infusion container maintains its shape against the external pressure. The inside becomes negative pressure and the infusion stops. Therefore, separately, the infusion container is punctured with a ventilation needle, or the spike needle is provided with a ventilation structure, and the atmosphere is introduced into the container so that the pressure in the infusion container is equal to the external pressure, and the infusion is performed. Prevent negative pressure inside the container.

For example, a conventional spike needle 31 shown in FIG.
Is provided with a liquid passage 3 inside the sharp tip 2,
An air passage (4) parallel to the liquid passage (3) is provided.
Are both open to the tip 2. A side pipe 5 is provided at the other end of the ventilation path 4, and the ventilation path 4 is connected to the outside air through a communication hole 7 provided at the bottom of a bottomed cylindrical intermediate body 6 fitted to the side pipe 5. I have contacted. At the opening end of the intermediate body 6, a hydrophobic porous filter 8 is mounted.

The porous filter 8 has air permeability and does not prevent the passage of outside air. However, since the porous filter 8 is hydrophobic, it does not allow drugs or the like flowing backward from the infusion container to the air passage 4 to pass therethrough.
The leakage of the drug or the like can be prevented.

When infusion of medicines or the like is performed by the infusion set, it is rare to use only one kind of medicine. In many cases, many medicines are co-injected into the infusion container according to a doctor's prescription. Is administered. The co-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 rigid container such as glass, the internal pressure of the infusion container becomes higher than the atmospheric pressure. Then, 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
However, even if leakage does not occur, when the drug or the like comes into contact, the precipitated component in the drug may be adsorbed to the pores to cause clogging, and a predetermined ventilation performance may not be obtained.

Therefore, in order to solve the above-mentioned problem of the porous filter 8, it has been proposed to provide a valve body in the side pipe 5 downstream 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 not-shown slit portion at the mountain-shaped top portion 43. When an external pressure is applied, the slit portion opens to allow the outside air to flow from the side pipe 5 to the air passage. 4 and is introduced into the infusion container. Further, when a drug or the like in the infusion container flows backward, the pressure closes the slit portion to prevent the drug or the like from leaking.

The spike needle 51 shown in FIG.
Non-return valve 5 with processed thermoplastic tube inside
2 is provided. The check valve 52 is formed by sealing the tip of a tube made of a thermoplastic material into a hemispherical shape, and forming a slit (not shown) on the hemispherical top 53. The spike needle 51 shown in FIG. 5 is similar to the spike needle 41 shown in FIG. 4, and when external pressure is applied, the slit is opened, so that outside air is introduced from the side pipe 5 through the ventilation path 4 into the infusion container, When the medicine or the like in the infusion container flows backward, the pressure closes the slit to prevent the medicine or the like from leaking.

The non-return valves 42 and 52 prevent the medicine or the like in the infusion container from flowing back before the porous filter 8 when the medicine or the like in the infusion container flows backward. An effect is also obtained that the contact can be prevented and the air permeability of the porous filter 8 can be maintained.

However, the check valves 42, 52
There is an inconvenience that the design is restricted due to the necessity of a space to be provided inside the side tube 5. In addition, the check valves 42 and 52 need to separately process a tube made of a rubber elastic body or a thermoplastic material, so that an increase in cost cannot be avoided.

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 provided in a hand pump in a door shape, and the like are also considered. Although these valves can cope with a sudden change in pressure, they are difficult to cope with a static pressure in which the medicine or the like comes into contact with the valve and gradually exudes, so that leakage of the medicine or the like is sufficiently prevented. There is a disadvantage that it cannot be prevented.

[0013]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made in view of the above circumstances. Thus, it is possible to prevent the liquid in a liquid container from leaking from an air passage with a simple structure, and to use an inexpensive medical device fluid. It is intended 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 is provided with a vent passage for supplying outside air to a liquid container for supplying a liquid to the outside through a fluid passage. A check valve for preventing liquid in the liquid container from leaking from the air passage, a communication hole for communicating the air passage with the outside air, and a check hole provided on the air passage side of the communication hole. A valve seat provided surrounding the communication hole; and a valve seat releasably provided on the valve seat, which is in close contact with the valve seat when the liquid in the liquid container flows back into the ventilation path, and the ventilation path side is under negative pressure. And a sheet-shaped valve element that separates from the valve seat when outside air enters the communication hole, and a sheet-shaped valve element that is provided to protrude into the valve seat from the ventilation path side and separates from the valve seat. And a support.

In the check valve according to the present invention, the seat-shaped valve element disposed on the valve seat is movable in a space defined by a support member protruding from the valve seat. . When the liquid in the liquid container flows back into the ventilation path, the sheet-shaped valve element closes the valve seat, thereby closing the communication hole and preventing leakage of the liquid. Further, the sheet-shaped valve element is separated from the valve seat by the external pressure when the air passage side becomes a negative pressure and outside air enters the communication hole, and a gap between the sheet-shaped valve element and the valve seat is formed. Thus, outside air can be introduced into the ventilation path. When the sheet-shaped valve element is separated from the valve seat, the sheet-shaped valve element is supported by the support, so that the sheet-shaped valve element is held in the valve seat and is prevented from being detached from the valve seat.

Since the sheet-shaped valve element is movable in the space defined by the support in the valve seat as described above, it is sensitive not only to a sudden change in pressure but also to static pressure. And the leakage of the liquid can be reliably prevented.

Further, according to the above configuration, it is sufficient if there is a volume within the valve seat where the sheet-shaped valve element can move in a space regulated by the support member, so that design restrictions can be reduced. . The sheet-shaped valve element can be used by punching or cutting out a synthetic resin film or the like having self-supporting properties. The synthetic resin film may be formed by any method such as extrusion molding, stretching molding, and rolling molding, and the cost can be reduced by using a general-purpose film such as a packaging material.

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

[0019]

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 configuration example of the fluid check valve of the 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 according to the present embodiment is used for a spike needle pierced into an infusion container of an infusion set. As shown in FIG. 1, the spike needle 1 has a sharp tip 2 pierced into a sealed rubber stopper of an infusion container (not shown),
A liquid passage 3 is provided therein for administering a liquid such as a medicine contained in the infusion container to a living body via 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 open to the distal end portion 2.

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

On the other hand, a recess 9 as a valve seat is provided on the side of the ventilation passage 4 of the intermediate body 6 so as to surround the opening of the communication hole 7, and a sheet-shaped valve body 10 is provided in the recess 9. ing. The ventilation path 4 is formed with a protrusion 11 protruding into the recess 9 so as to face the communication hole 7, and the valve body 10 is movable in the space between the bottom surface 9 a of the recess 9 and the protrusion 11. The check valve of the present embodiment is formed by the recess 9, the valve element 10, and the protrusion 11.

The side tube 5 has a cover 1 having a through hole 12.
3, the porous filter 8 is sandwiched between the flange 6a of the intermediate body 6 and the lid 13. The spike needle 1 is punctured in a flexible infusion container such as an infusion bag made of a soft synthetic resin, and when there is no need to maintain the internal pressure of the infusion container equal to the external pressure, the through-hole 12 is formed by a special cap or the like. Closed.

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

First, when the spike needle 1 is pierced into the hermetically sealed rubber stopper of the infusion container and the infusion is performed, the inside of the infusion container has a negative pressure in a normal state.
Is separated from the bottom surface 9a of the concave portion 9 and moves to the protrusion 11 side. At this time, the protrusion 11 functions as a support that supports the valve body 10 so as not to be detached from the recess 9 that is a valve seat.

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

Next, when another medicine is co-injected into the infusion container and the pressure in the infusion container becomes larger than the outside pressure, the medicine and the like in the infusion container flow back to the ventilation path 4. At this time, the valve element 10 responds to the pressure of the backflow of the drug or the like, and as shown by a virtual line in FIG.
a. As a result, it is possible to prevent the communication hole 7 from being closed by the valve body 10 and to leak the medicine or the like to the outside.

The valve element 10 is non-toxic to living organisms and inert to drugs.
A self-supporting synthetic resin film 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, when the valve body 10 is in close contact with the bottom surface 9a of the concave portion 9 and closes the communication hole 7, it becomes difficult to prevent leakage against the pressure of the back-flowing drug or the like. When the thickness of the synthetic resin film exceeds 200 μm, the air passage 4
When the outside pressure is applied to the valve body 10 due to the negative pressure on the side, the valve body 10 may not be able to be separated from the bottom surface 9a of the concave portion 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 element 10 can operate with high sensitivity even at a pressure drop of about 60 cm. 7
Preferably, it is 0 μm.

The synthetic resin film preferably has a specific gravity of 2.4 or less, more preferably 1.0 or less, in order to promptly open and close the film with high sensitivity.

The synthetic resin film may be manufactured by any method such as extrusion molding, stretching molding, and rolling molding, and a general-purpose film such as a packaging material can be used. By cutting or cutting out the synthetic resin film, the shape of the valve body 10 can be easily adjusted, and special equipment is not required for processing the valve body 10, thereby reducing manufacturing costs. Can be.

The protrusion 11 is in contact with the valve body 10 so that the valve body 10 quickly separates from the tip of the protrusion 11 and comes into close contact with the bottom surface 9a of the recess 9 when the medicine or the like flows backward. Preferably, the area is as small as possible. Due to the above operation, in the present embodiment, the protrusion 1
Although the tip of 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.

An adhesive (not shown) is provided on the bottom surface 9a of the concave portion 9 so as to increase the adhesion of the valve body 10 and the pressure resistance to the backflowing drug and the like, and to allow the adhesion and peeling to be repeated many times. Layers are provided. The pressure-sensitive adhesive layer is formed by applying a suitable pressure-sensitive adhesive to the bottom surface 9a.

The pressure-sensitive adhesive is not toxic to living organisms and inert to drugs, and therefore, for example, silicone oil is suitable. The silicone oil has a viscosity of 1 so that it can be applied uniformly without dripping onto 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 element 10 can be in good contact with and peel off from the bottom surface 9a.

In the present embodiment, an example is described in which the check valve is applied to the spike needle 1 of an infusion set. However, the present invention prevents the liquid in the liquid container from flowing backward while preventing the liquid from flowing in the liquid container. The present invention can be applied to other medical devices that need to introduce gas.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view showing a configuration example of a fluid check valve of a medical device of the present invention.

FIG. 2 is an operation explanatory view showing an enlarged main part of FIG. 1;

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

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

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

[Explanation of symbols]

4 ... ventilation passage, 7 ... communication hole, 9 ... valve seat, 9a ... bottom surface, 10 ... sheet-like valve body, 11 ... support.

Claims (3)

[Claims] 1. A check valve provided in an air passage for supplying outside air to a liquid container for supplying liquid to the outside via a liquid passage, and for preventing liquid in the liquid container from leaking from the air passage. A communication hole communicating the ventilation path with the outside air; a valve seat provided on the ventilation path side of the communication hole so as to surround the communication hole; A sheet-like valve body that comes into close contact with the valve seat when the liquid in the liquid container flows back into the passage and that has a negative pressure on the side of the ventilation path and that separates from the valve seat when outside air enters the communication hole; A fluid check valve for a medical device, comprising: a support member that protrudes into the valve seat from the ventilation path side and supports a sheet-shaped valve element that is peeled off from the valve seat. 2. The fluid check valve for a medical device according to claim 1, wherein said sheet-shaped valve element is made of a synthetic resin film having self-supporting properties. 3. The fluid check valve according to claim 1, wherein an adhesive layer is provided on a bottom surface of the valve seat.