JPS61211577A - Check valve - Google Patents

Abstract

PURPOSE:To obtain sure sealing effect even if counter flow pressure is small by forming a Y-letter type notch on one end of a flow path with the diameter of its flow-out port for preventing counter flow shortened in tapered shaped and forming a tapered pressure receiving face on the outer periphery. CONSTITUTION:A flow-in port 3 of fluid is provided on one end of a flow path 2 formed by soft elastic material and provided in the axial direction of the center, and a Y-letter notch is formed on the other end of the flow path 2 by shortening in a tapered shape the diameter of a flow-out port 6 for preventing counter flow. And a tapered pressure receiving face 10 is formed between Y-letter type projections on a Y-letter type outer peripheral portion. Then, when fluid flows out, the flow-out port 6 is opened in almost circular shape. When the fluid flows from the flow out port in reverse direction, this counter flow pressure is received by the tapered pressure receiving face 10, then the flow-out port 6 is subjected to a pressing force in the closing direction and counter flow can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a check valve for controlling the direction of fluid flow, and is particularly advantageous when inserted into a pipe.

Conventional technology As disclosed in Utility Model Application No. 58-165370, a fluid inlet is provided at one end of a flow passage formed of a soft elastic material and provided in the axial direction of the central portion, and a backflow prevention device is provided at the other end of the flow passage. There is a check valve that has a tapered outlet and is recessed into a negative shape. When the fluid flows out, the outflow port is opened in an elliptical shape, which is extremely small compared to the area of the inflow port, and the pressure difference between the inflow pressure from the inflow port and the outflow pressure from the outflow port is This tendency is not only more pronounced as the flow rate of fluid increases, but also causes many accidents that result in damage due to the inability to withstand the increase in flow rate from the inlet.

In order to eliminate this drawback, the present applicant proposed a check valve having a cross-shaped outlet in Japanese Patent Application No. 59-271422. In this method, when the fluid that has flowed in from the inlet flows out, the outlet that has been cut into a cross shape is opened in a substantially circular shape, ensuring an opening area that is almost the same as the area of the fluid inlet. This enables the pressure difference between the inflow pressure from the fluid inlet and the outflow pressure from the fluid outlet to be small, minimizing the occurrence of pressure loss, and reducing the risk of damage even when the fluid flow rate increases. It has the great advantage of being able to obtain a stop valve, but
When fluid flows backwards from the outlet direction, the sealing properties are poor and unless a certain amount of backflow fluid pressure is applied to the outlet, the sealing effect will not occur.
It had a defect 7α that caused a backflow of fluid.

Problems to be Solved by the Invention The present invention attempts to eliminate the above-mentioned drawbacks by reducing the pressure difference between the fluid pressure flowing in from the fluid inlet and the fluid pressure flowing out from the fluid outlet. , minimizes pressure loss, reduces the possibility of damage even when the flow rate of fluid flowing in from the inlet is large, and produces a reliable sealing effect even when the backflow pressure of fluid is small, improving sealing characteristics. Good, what you're trying to get is a check valve.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention is made of a soft elastic material, and a fluid inlet is provided at one end of the flow passage provided in the central axial direction. At the other end, an outflow port for preventing backflow is tapered and cut into a Y-shape.
A tapered pressure receiving surface is formed between the Y-shaped protrusions on the outer circumferential surface of the shaped part.

As described above, the present invention is made of a soft elastic material, has a fluid inlet at one end of the flow passage provided in the axial direction of the central part, and has a tapered outlet at the other end of the flow passage for preventing backflow. The diameter is reduced to form a Y-shaped cut, and a tapered pressure receiving surface is formed between the Y-shaped protrusions on the outer peripheral surface of this Y-shaped part, so that the fluid flowing in from the inlet is When it flows out, Y
This is done by opening the outflow port, which is cut into a letter-shaped cut, into a substantially circular shape, making it possible to secure an opening area close to the area of the fluid inflow port, thereby increasing the inflow pressure from the fluid inflow port and the flow rate from the outflow port. The pressure difference between the flow rate and the outflow pressure is small, which reduces the occurrence of pressure loss and reduces the possibility of damage even when the flow rate of fluid increases. In addition, when fluid flows backward from the outlet direction, this backflow pressure is received by the tapered pressure receiving surface, and a pressing force is applied to the outlet in the closing direction.
Backflow can be prevented.

In addition, by forming the outlet in a Y-shape, the area of the tapered pressure-receiving surface can be larger than in the case where the outlet is formed in a cross-shape. Since the total length is shortened, the strength of the outlet increases, and the sealing performance against backflow can be improved to the same level as a minus-type outlet.

EXAMPLE Below, one example of the present invention will be explained with reference to the drawings.(1)
is a cylindrical body made of a soft elastic material such as silicone rubber, 70% silicone rubber, or acrylonitrile butadiene rubber, and has a fluid inlet (3) at one end of a flow path (2) provided in the axial direction of the central part. 7 ranks (4) for fixing the target part protrude from the outer periphery of the inlet (3), and an annular rib (5) for fixing is provided at an appropriate interval from the 7 runs (4).
protrudes from the outer periphery. In addition, at the other end of the flow path (2),
The diameter of the outflow port (6) for preventing backflow is reduced in a tapered shape, and Y-shaped cuts are formed at an interval of 120° so that it opens when fluid pressure is applied from the direction of the inflow port (3). This Y
Between the Y-shaped protrusions (8) on the outer peripheral surface of the shaped part (7), there are 12
A tapered pressure receiving surface (10) is formed that intersects at an angle of 0°.

In order to install and use the check valve formed in this way in the intended part, it is only necessary to position the inlet (3) in the direction of fluid inflow and the outlet (6) in the direction of fluid outflow. , tube body (
11) is explained with reference to FIG.
6), and engage the annular rib (5) with the annular recess (14) provided on the inner periphery of the one-way throttle tube (12), and engage the 7 runno (4) with the open end surface (15). By this,
Fix the position.

Next, fit the other connecting pipe (16) to the outer periphery of the one-way throttle pipe (12) and fix the fitting part (17). is fixed irremovably.

In the one formed as described above, the other connecting pipe (16
) through the inlet (3), the fluid flows into the outlet (3) through the outlet (
When flowing out from the inlet (6), the outlet (6), which is formed by Y-shaped cuts at 120° intervals, is opened in a nearly circular shape, so the outlet (6) is connected to the inlet (3). It is possible to secure a similar opening area, and the pressure difference between the inflow pressure of the fluid from the inlet (3) and the outflow of the fluid from the outlet (6) is small, reducing the occurrence of pressure loss. Since the pressure difference is small, damage is less likely to occur even if the fluid flow rate is large.

The inflow pressure of the fluid from the inlet (3) and the outlet (6)
) of the product implementing the present invention.
A check valve with a Y-shaped outlet (6) at 20° intervals, a check valve with a cross-shaped outlet that has been applied for by the present applicant, and a conventionally known minus check valve with a cross-shaped outlet If compared with a check valve provided with a molded outlet, the flow rate characteristic graph shown in FIG. 3 will be obtained. In FIG. 3, the ○ mark is a check valve provided with Y-shaped outlet ports (6) at 120° intervals, and the mu mark is a check valve provided with a conventionally known minus-type outlet port. Δ is a check valve with a cross-shaped outlet, which has been applied for by the present applicant, and the flow rate on the vertical axis uses a logarithmic scale. In addition, the three check valves mentioned above have an inner diameter of 3,4 I and a length of 111 III m, and other than the difference in that the outlet is Y-shaped, cross-shaped, or minus-shaped, they have the same dimensions and are made of the same material. However, air is used as the fluid. As is clear from Fig. 3, the difference in pressure difference between the outflow port (6) and the inflow port (3) in the three check valves mentioned above is, for example, when the cross-shaped inflow port is When provided, the differential pressure is approximately 150 mmAg,
The negative type of the conventional and unknown product is about 450 mmA g,
Further, the product according to the present invention, in which the outlet is provided at 120° intervals, has a pressure difference of about 300+ao+Ag, which is between the two, and has a smaller differential pressure than the negative type outlet.

In addition, when fluid flows backward from the direction of the outlet (6), this backflow pressure is received by the tapered pressure receiving surface (10), so that a pressing force is applied to the outlet (6) in the closing direction, and the backflow can be prevented.

To prevent this backflow, by forming the outlet (6) in a Y-shape, the area of the tapered pressure-receiving surface (10) can be larger than in the case where the outlet (6) is formed in a cross-shape. At the same time, the total length of the notches of the outlet (6) is shortened, so the strength of the outlet (6) is increased, and the sealing performance against backflow can be improved to the same level as a minus-type outlet. Become something. This sealing characteristic is shown in a bar graph in Figure 4. When backflow pressure is applied to check valve A with a cross-shaped outlet, a sealing effect begins to occur at a pressure of 100,100 Og, and a negative type B and Y
In a C-shaped reverse valve with each outlet, 200
The sealing effect is produced by the backflow pressure of tsta A g.

Effects of the Invention As described above, the present invention is made of a soft elastic material, has a fluid inlet at one end of the flow passage provided in the axial direction of the central part, and has an outlet for backflow prevention at the other end of the flow passage. The diameter is reduced in a tapered shape to form a Y-shaped cut, and a tapered pressure receiving surface is formed between the Y-shaped protrusions on the outer peripheral surface of this Y-shaped part, so that the inflow from the inlet is When the fluid flows out, Y
The outflow port is cut in the shape of a letter and is opened in a shape close to a circle, making it possible to secure an opening area close to the area of the fluid inlet. To obtain a check valve in which the pressure difference between the outlet pressure and the outlet pressure is smaller than that provided with a negative outlet, the occurrence of pressure loss is small, and damage is less likely to occur even when the flow rate of fluid increases. I can do things.

Furthermore, by forming the outlet in a Y-shape, the area of the tapered pressure-receiving surface can be larger than in the case where the outlet is formed in a cross shape, and the total cut length of the outlet can be shortened. Therefore, the strength of the outlet is increased, and the sealing performance against backflow can be improved to the same level as a negative-type outlet.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; Fig. 1 is a perspective view, Fig. 2 is a cross-sectional view of the state installed in a pipe body, and Fig. 3 shows a product implementing the present invention and a conventionally known negative type outlet. Fig. 4 is a graph showing the sealing characteristics of a product implementing the present invention, a conventionally known product with a negative type outlet, and a positive type outlet. (2)・・・Flow path (3)・・・Inflow port (
6)・・・Outlet (7)・・・Y-shaped part (8
)...Y-shaped protrusion (10)...Pressure surface Fig. 1 Fig. 42 Fig. 3 (g/, η old) Differential pressure (mmAQJ No. 411 BC

Claims (1)

[Claims] Made of soft elastic material, a fluid inlet is provided at one end of the flow passage provided in the axial direction of the central part, and an outlet for preventing backflow is tapered at the other end of the flow passage to form a Y-shape. A check valve characterized in that a notch is formed in the Y-shaped portion, and a tapered pressure receiving surface is formed between the Y-shaped protrusions on the outer peripheral surface of the Y-shaped portion.