JPH06697Y2 - Check valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is an improvement of a flat check valve used for an article such as a balloon toy, a water bladder, etc. that is densely filled with a fluid such as air or liquid. In this regard, it is used in the industrial field of manufacturing and selling this type of valve.

(Prior Art) A wide variety of flat check valves have been conventionally proposed and implemented for hermetically sealing a required fluid into a balloon toy made of plastic film, rubber or the like, or a water bladder. For example, as disclosed in Japanese Utility Model Application Laid-Open No. 50-12320, after inserting the tip of the injection tube between two thin film-like substrates having adhesion, polymerization of the two substrates is performed. There is known a check valve having a linear flow path in which only the overlapping portion of the leading edge portion is left and other surrounding portions are fused.

Further, in order to improve the effect of preventing the backflow of the fluid by the check valve, a check valve in which another check valve is further installed in the linear flow path of the check valve of the flat tubular body. as,
For example, the actual fairness 1 that was previously developed by the inventor of the present invention.
A check valve as described in Japanese Patent No. 35019 is known.

(Problems to be Solved by the Invention) However, the former check valve in the above-mentioned conventional example has an advantage that the structure is simple and can be provided easily and inexpensively, but has the following serious drawbacks. That is, this check valve has its main body part mounted in, for example, a rubber balloon, injects air from its injection tube to inflate the rubber balloon, and the filled air pressure causes the outer peripheral surfaces of the two substrates to be separated. By pressurizing and bringing the inner surfaces of the two substrates into close contact with each other, the outflow of the filled air is prevented. A certain check effect can be expected, but the fluid flow path is formed in a straight line. Therefore, if pressure is applied from both sides of the check valve during use, the gap-shaped flow path may become tubular, and there is a serious problem that the filled air flows out.

Further, the latter check valve in the conventional example can exhibit an excellent fluid outflow prevention effect by the valve body composed of a folded piece that is installed in the flow path, but the structure is slightly complicated. There is a problem of high cost.

The present invention was developed with the object of solving the above-mentioned problems, and an improvement was made to the former type of check valve in the above-mentioned conventional example to simplify the structure and to achieve a remarkable effect of preventing fluid backflow. The purpose is to provide an excellent check valve.

(Means for Solving the Problems) As means for solving the above problems and achieving the object,
According to the present invention, in a check valve having a fluid passage in a gap shape in which two heat-fusible plastic films are laminated to form a flat tubular body, the passage is bent at at least one place. The configured check valve was developed and adopted.

Further, in the check valve configured as described above, the check valve is bent in a zigzag shape at a plurality of locations to form a flow path, and the openings at both ends of the check valve are not directly connected by the bent portions. Each of the configured check valves was developed and adopted.

(Operation) Since the check valve according to the present invention is configured as described above, for example, one side of the check valve is inserted into the floating balloon toy, and the other side is installed with the other side protruding outward. When used as a check valve for filling the gas of the balloon toy, the following effects are obtained.

When the balloon toy is inflated by filling gas from the opening of the projecting end, the gas pressure causes the two plastic films in the part inserted into the balloon toy to be pressed from both sides to be in close contact with each other to form a gap. Since the flow path is sealed, it has the function of reliably preventing the backflow of gas.

In addition, even if pressure is applied from both sides of the check valve during use, the fusion-bonded edge of the bent portion acts like a rib, effectively preventing the flow passage from opening and providing a check function. Hold.

Furthermore, if the openings at both ends of the check valve are configured so as not to be directly communicated by the bent portions, even if the flow passage is opened at a part of the margin of the bent portion due to pressure from both sides. , Has the effect of effectively preventing the spread of its opening.

(Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. FIGS. 1 to 4 show the first embodiment, and the check valve 1 is made of polyethylene film or the like. Two heat-fusible plastic films 1a and 1b are superposed, and a predetermined width interval is maintained, and both side edges of the interval are heat-sealed in a zigzag shape to provide bent portions 2 at three positions and the upper end thereof. A rectangular portion 3 having a short dimension is extended to a portion, and the rectangular portion 3 on one film 1a side is extended to be slightly longer than the rectangular portion 3 on the other film 1b side to form a guide tongue piece 4. Thus, the zigzag-shaped flow path 7 is formed by the flat tubular body having the gaps and having the openings 5 and 6 at the upper and lower ends. In this embodiment, the tips of the adjacent bent portions 2 bent toward the flow path side are arranged so as to slightly exceed the center line L. With this configuration, the openings 5 at both ends of the check valve 1 are provided. 6 is not connected in a straight line by the bent portions 2.

The check valve 1 configured as described above is, for example, as shown in FIG. 5 and FIG. 6, an embodiment illustrated in a hermetically sealed bag C made of a plastic film having airtightness and watertightness such as gas and liquid. The air supply nozzle is inserted into the upper opening 5 of the check valve 1 by utilizing the guide tongue 4 and air is supplied to inflate the bag C. When the air supply nozzle is pulled out by the air pressure, the two films 1a and 1b at the insertion portion of the check valve 1 are pressed from both sides by the air pressure and come into close contact with each other as shown by the arrow in FIG. Since the flow path 7 is sealed, the filled air is surely enclosed without backflow.

Further, according to this embodiment, even if pressure is applied from both side edges of the check valve 1 during handling and use such as transfer of the bag C filled with air, the fusion bonding edges of the respective bent portions 2 are There is an advantage that it can act like a rib to effectively prevent the flow path 7 from being opened in a tubular shape, and the opening portions 5 and 6 at both ends of the check valve 1 can be effectively prevented.
Since, as described above, the bending portions 2 are not directly communicated with each other, even if the flow passage is opened in a cylindrical shape at one part of the marginal edge of the bending portion 2 due to the pressing force from both sides, the opening There is an advantage that the propagation can be reliably prevented and the backflow prevention effect of air can be further improved.

Next, each check valve 1 shown in FIGS. 7 to 10 shows another embodiment of the present invention.

In the second embodiment shown in FIG. 7, the tips of the adjacent bent portions 2 bent toward the flow path 7 are arranged so as to greatly exceed the center line L to further improve the above-mentioned effect. It differs from the first embodiment only in the points that are achieved.

Further, the third embodiment shown in FIG. 8 is different from the first embodiment only in that each bent portion 2 is formed in a gentle curve shape so as to facilitate the supply and discharge of fluid.

Furthermore, the fourth embodiment shown in FIG. 9 shows a modification of the third embodiment corresponding to the second embodiment, and the fifth embodiment shown in FIG. The present embodiment is different from the above-mentioned embodiments in that it is provided with the flow path 7, and in this embodiment, the single bent portion 2 does not linearly connect the openings 5 and 6 at both ends. It is not an essential requirement of the present invention that the openings 5 and 6 at both ends are not connected in a straight line.

In the second to fifth embodiments, the same parts as those in the first embodiment are designated by the same reference numerals.

Further, although not shown, if a valve body having the following structure developed by the inventor of the present invention is installed in the flow path 7 of the check valve 1 of the present invention, a bag body, etc. It is possible to further improve the effect of preventing the backflow of the fluid filled and sealed in.

That is, in the flow path 7 of the check valve 1, a two-fold folding of a plastic film is provided, which has a bent portion on the front end side which is arranged toward the fluid inlet side and an open portion on the base end side. The valve body is formed of a bent piece, and both side edges of the valve body are adhered to the both side edges of the flow pipe, respectively, and the bent portion of the valve body forms a blocking portion for preventing the outflow of fluid. If a valve main body formed by forming a fluid flow path with a gap formed between both inner side surfaces of the valve main body and both outer side surfaces of the valve main body is provided, the structure becomes a little complicated, As described below, the effect of preventing the backflow of the enclosed fluid can be dramatically improved. That is, when the fluid is supplied into the flow passage 7 of the flow pipe from the direction in which the bent portion of the valve body is located, the fluid is formed between both inner side surfaces of the flow pipe and both outer side surfaces of the valve body. It smoothly circulates through the two gaps, and the fluid flows into the bag body such as a balloon toy to inflate it. On the other hand, the fluid filled inside the bag of a balloon toy or the like, even if it tries to flow out,
Since the outer peripheral surface of the flow pipe is pressed by the restoring pressure of the bag body of the expanded balloon toy or the like or the pressure of the filled fluid, the valve body is blocked because the tip side is blocked. The pressure of the fluid that has entered the valve body from the open part of the valve is significantly increased, and the strong inner pressure strongly pressurizes both inner side surfaces of the valve body, expands the valve body and tightly closes the gap, and the fluid flows out. Prevent. Further, the discharge of the filled fluid is smoothly performed by inserting a thin rod or the like into the sealed gap from the closed side and pushing the rod open.

Although the main embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and the scope of the present invention can be achieved without departing from the gist of the present invention.
It goes without saying that various design changes regarding shape, material, etc. are possible.

(Effect of the Invention) In the present invention, in a check valve having a fluid passage in a gap shape in which two heat-fusible plastic films are superposed to form a flat tubular body, at least one passage is provided. Since this is a check valve characterized by being bent at a portion, this check valve is a cheap check valve with a simple structure consisting of only two films. Even if pressure is applied from both side edges of the check valve while handling the sealed bag of the used fluid, the fused edges of the bent portion act like ribs and the flow path opens in a tubular shape. There is a great advantage that it can be reliably prevented, and thus the backflow of the fluid filled and sealed in the bag can be effectively prevented.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a front view of the first embodiment, FIG. 2 is an exploded view thereof, and FIG. 3 is A of FIG.
-An enlarged sectional view taken along the line A, FIG. 4 is an enlarged sectional view taken along the line BB in FIG. 1, FIG. 5 is a front view showing one state of use, and FIG. 6 is CC in FIG. 7 is a front view showing a second embodiment to a fifth embodiment of the present invention, respectively. (Explanation of Codes) 1 ... Check valve, 1a / 1b ... Heat-fusible plastic film, 2 ... Bent portion, 5/6 ... Opening at both ends, 7 ... Flow path.

Claims (3)

[Scope of utility model registration request] 1. A check valve having a flow path for a fluid in a gap shape in which two heat-fusible plastic films are stacked to form a flat tubular body, and the flow path is bent at at least one place. A check valve characterized by being configured as follows. 2. The check valve according to claim 1, wherein the flow path is formed by bending in a zigzag shape at a plurality of locations. 3. The check valve is configured so that the opening portions at both ends thereof are not directly connected by a bent portion.
The check valve according to (1) or (2).