JPH019568Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement in an aeration needle that is inserted together with a liquid guide needle into a stopper of a container filled with various medical infusions.

Generally, this type of ventilation needle is used when injecting various infusions such as amino acids, vitamins, other nutrients, hemostatic agents, anesthetics, etc. into the veins of a living body.
It is used to introduce an infusion into an infusion device connected to a liquid guide needle by inserting the needle into the stopper of the container and introducing outside air into the inverted container.

Conventionally, as illustrated in FIGS. 1 and 2, an infusion device 3 is attached to a stopper 2 of a container 1 filled with an infusion solution.
A ventilation needle 5 punctured together with a liquid guide needle 4 connected to
is usually formed of a needle part 6 and a cylindrical body part 7 having a base part 7a at one end into which the needle part 6 is inserted and fixed, and a ventilation passage on the other end side of the opening of the body part 7. It is well known that an air filter 8 made of a hydrophobic substance is provided to collect bacteria, floating dust, etc. in the outside air.

However, with such a conventional structure, when the container 1 is in an inverted position and the infusion is started, the clamp 3a of the infusion device 3 is closed and the inside of the container is under positive pressure, so ventilation is not allowed in this state. As soon as the needle 5 is inserted into the stopper 2 of the container 1,
The infusion fluid flows into the ventilation needle (indicated by the dotted arrow in Figure 2), temporarily blocking the ventilation path, and then when the clamp 3a is opened, the pressure inside the container gradually decreases and the ventilation needle closes. The infusion solution inside the container flows back into the container due to the introduction of outside air (indicated by the solid line arrow in Figure 2).
For this reason, not only bacteria or floating dust in the outside air adhering to the air filter 8 installed in the ventilation path of the ventilation needle get mixed into the container, but also the infusion liquid that has permeated the air filter 8 tends to leak to the outside. When the filter 8 got wet, various problems occurred, such as making the introduction of outside air unstable and adversely affecting the dripping rate and flow rate of the infusion.

This invention aims to eliminate the above-mentioned conventional drawbacks, and its gist is that the needle is inserted and fixed into the base at one end, and the air filter is installed at the open end of the outside air inlet at the other end. In a ventilation needle consisting of a cylindrical body with A ring-shaped substrate is disposed on the inner surface of the air filter facing the air filter, and a rising dam is formed protruding from the inner peripheral edge of the ring-shaped substrate, while the rising dam is covered with the inner surface of the ring-shaped substrate. A rising partition body made of a thin plate elastic material is provided, and a ventilation hole is opened on the peripheral side corresponding to the bulging head of the rising weir portion of the partition body, and the partition wall The body is characterized in that it can be elastically deformed by the pressure of the inflowing infusion caused by puncturing the needle into the infusion container, and the vent hole is tightly closed at the head of the rising dam.

Next, this invention will be explained based on an embodiment shown in FIG. 3. In the figure, numeral 11 is a ventilation needle body.
The ventilation needle main body 11 includes a needle portion 12, a cylindrical body portion 13 formed at one end with a base portion 13a into which the needle portion 12 is inserted and fixed, and the other end of the body portion 13 has a tapered shape with a wide end. Opening end 13b serving as an outside air introduction port expanded to
and an air filter 15 which is clamped and fixed to the body via a fixing member 14, and a ring-shaped substrate 16 is arranged on the inner surface of the air filter 15 facing into the body 13. A rising weir portion 17 having a bulging head 17a is provided around the inner peripheral edge of the ring-shaped substrate 16, and further on the inner surface side of the ring-shaped substrate 16, there is provided a raised weir portion 17 made of a thin elastic material such as a film. A rising partition wall 18 is arranged to cover the ring-shaped substrate. A ventilation hole 1 is provided in the rising peripheral side surface 18a of the partition wall body 18.
9 is opened so as to correspond to the head 17a of the rising weir part 17 of the ring-shaped base plate 16, and its upper end face 18b, that is, the insertion end 12a of the needle part 12
The rising end surface corresponding to the curve is concave in an arc shape.

That is, in this invention, the other end of the cylindrical body 13 constituting the ventilation needle body 11, which is the open end 13b of the outside air inlet, is expanded into a tapered shape that widens at the end. 13, and when the needle part 12 of the ventilation needle main body 11 is inserted into the stopper part 2 of the infusion solution enclosure 1 which is in an upside down state during the initial start operation of infusion dripping, the needle Part 1
The rising partition wall body 18 is elastically deformed by the inflow pressure of the infusion fluid flowing into the ring-shaped substrate 16, and its circumferential side surface 18a is pressed into contact with the rising weir part 17 provided around the inner peripheral edge of the ring-shaped base plate 16. Then, the vent hole 19 of the rising partition wall 18 communicating with the outside air inlet is tightly sealed by the head 17a of the rising weir portion 17, and the pressure in the internal space of the cylindrical body portion 13 is kept below a certain level. The backflow of the infusion is reduced by preventing the infusion from dropping, and the infusion that flows back from the needle part 12 and flows into the internal space of the cylindrical body part 11 is transferred to a rising edge provided around the inner peripheral edge of the ring-shaped substrate 16. The dam part 17 is dammed and secondary sealed to prevent the infusion from leaking to the outside, and to prevent the air filter 15 provided at the open end 13b of the outside air inlet of the cylindrical body 11 from getting wet with the infusion. It is what it is.

Therefore, according to the configuration of this invention described above, a valve mechanism consisting of a ring-shaped substrate and a partition is provided in the body of the ventilation needle body, and the valve mechanism is closed as the infusion fluid flows in. Therefore, the infusion fluid is retained by the rising dam and does not leak to the outside, and it is possible to reliably prevent bacteria in the outside air or floating dust from entering the container due to the air filter becoming wet. The air filter itself
You can freely select whether it is hydrophilic or hydrophobic, and the infusion after infusion can completely flow back into the container as soon as the clamp of the infusion device is opened, while the infusion backflow Afterwards, the pressing action of the partition wall body is released and the partition body returns elastically, so that outside air can be introduced smoothly, which has excellent practical effects.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the usage state of a conventional infusion vent needle, Fig. 2 is an explanatory diagram showing the backflow phenomenon of infusion fluid flowing into the vent needle, and Fig. 3 is an explanatory diagram showing the infusion vent needle according to this invention. FIG. 2 is a sectional view showing one embodiment of the invention. 11... Ventilation needle body, 12... Needle part, 13...
Body, 13a...base, 13b...outside air inlet,
15...Air filter, 16...Ring-shaped substrate, 17...Rising dam, 18...Rising partition, 18a...Surrounding side, 19...Vent hole.

Claims (1)

[Scope of utility model registration request] In a ventilation needle consisting of a cylindrical body in which a needle is inserted and fixed at one end base and an air filter is provided at the open end of the outside air inlet of the other end, the opening end of the outside air inlet of the cylindrical body. A ring-shaped substrate is disposed on the inner surface of the air filter, the other end of which is widened into a tapered shape, and which faces inside the tapered open end, and a rising weir is formed on the inner peripheral edge of the ring-shaped substrate. A rising weir portion is formed to protrude, while a rising partition body made of a thin plate elastic material is provided on the inner surface side of the ring-shaped substrate so as to cover the rising weir portion, and the rising weir portion of the partition body is formed to protrude. It has a configuration in which a ventilation hole is opened on the peripheral side corresponding to the head,
The said partition body is made elastically deformable by the pressure of the inflowing infusion accompanying the puncture of the needle part into the infusion liquid enclosure container, and the said ventilation hole is closely closed with the head of a rising weir part. needle.