JPH11166645A - Check valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a check valve wherein while having an effect of preventing a reverse flow of an air flow by dead weight of a valve element, a burden for pressing up the valve element so as to make air flow in a positive direction as smooth as possible is made as light as possible, and a fan capacity is set to a required minimum limit. SOLUTION: In a check valve 1 comprising a valve casing 2 inserting as inflow duct 3 having an air inflow port 5 formed in slope shape to one end and an outflow duct 4 having an air outflow port to the other end and a valve element 6 having a valve shaft 8 on an extension of an opening surface of the air inflow port 5 to open/close it with the valve shaft 8 serving as the support point, an upper part of the valve element 6 is flexed to a side of the outflow duct 4, the valve shaft 8 is provided in a side of the outflow duct 4, rather than the extension of the opening face of the air inflow port 5 and also in such a range that the valve element 6 is not separated from the air inflow port 5 by dead weight of the valve element 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a check valve for air piping.

[0002]

2. Description of the Related Art In various piping facilities, a check valve 54 is interposed in the middle of a pipe.
As shown in FIG. 3, a valve box 55, an air inflow duct 50 inserted in the valve box 55, an air outflow duct 56 inserted in the valve box 55, and an air inflow duct 50 And a valve element 52 having a fulcrum 53 on the extension of the opening surface of the valve 50. The valve element 52 allows the inflow port 51 formed by diagonally cutting the duct 50 to be openable and closable. When there is no air flow inside, the valve body 52 closes the inflow port 51 by its own weight as shown by the solid line in the figure. On the other hand, when air flows in the forward direction (arrow C in FIG. 3) that pushes up the valve body 52 in the duct 50, the valve body 52
Is pushed up by the pressure and becomes a state shown by a broken line in the figure, whereby the airflow from the inlet 51 of the duct 50 to the outlet 57 of the duct 56 is allowed. Further, for the air flow in the reverse direction (arrow D in FIG. 3), the inflow port 51 is closed by the weight of the valve body 52, and the reverse flow of the air flow is prohibited.

Such a check valve 54 is provided, for example, in a duct connecting a grain dryer and a dust collector in a country elevator or the like.
Dust and the like once collected by the dust collector are prevented from flowing into the grain dryer again.

Since the inlet 51 is closed by the weight of the valve body 52, the inlet 51 is always closed and opened only when air flows in the forward direction.
Since the inflow port 51 is closed by the weight of the valve body 52, the flow of air in the forward direction must pass through by pushing away the weight of the valve body 52. Therefore, the amount of air passing through the check valve 54 is The amount of air required for the subsequent device and the amount of extra air required to push the valve body 52, in other words, the amount of air required to push the valve body 52, must be taken into account. If a large number of such check valves are installed, extra fan capacity is required.

In order to reduce the load, the valve body 5
The opening and closing of the valve 2 may be mechanically performed by detecting the generation of an air flow in the duct 50. In this case, a sensor for detecting the air flow in the duct 50 and an opening / closing device for the valve body 52 are required. Thus, there is a problem that the cost increases and the configuration becomes complicated.

[0006]

DISCLOSURE OF THE INVENTION The present invention has a simple structure that does not increase the cost and has the effect of preventing the backflow of the air flow due to the weight of the valve body, while allowing the air in the forward direction to flow as smoothly as possible. It is a technical object to provide a check valve capable of minimizing a load for pushing up a valve body and reducing a fan capacity.

[0007]

In order to solve the above-mentioned problems, the present invention comprises an inflow duct having an inclined air inlet at one end and an outflow duct having an air outlet at the other end. A check valve comprising: a valve box having a valve shaft on an extension of an opening surface of the air inlet, and a valve body for opening and closing the air inlet with the valve shaft as a fulcrum. Is bent toward the outflow duct, and the valve shaft is positioned closer to the outflow duct than an extension of the opening surface of the air inflow port, and the valve body is moved by the own weight of the valve body. A technical measure was taken to provide it within the area not far from the entrance.

It is preferable that the valve shaft is provided at a position where the valve body does not bias the outlet duct side and the inlet duct side.

Preferably, one side wall of the valve box is detachably formed.

[0010]

FIG. 1 is a longitudinal sectional view of a check valve 1 according to the present invention. The check valve 1 includes a valve box 2 having an upper wall 12 detachably formed, and a valve box 2 having a detachable upper wall 12. An air inflow duct 3 fitted in the side wall, an air outflow duct 4 fitted in the other side wall of the valve box 2, and an inflow port 5 formed by diagonally cutting the inflow duct 3 are connected to the valve shaft 8. And a valve element 6 that opens and closes as a fulcrum.

The valve body 6 is provided with an opening / closing portion 7 which opens and closes the inflow port 5 in contact with the opening surface of the inflow port 5, and is bent toward the outflow duct 4 from an extension of the opening / closing portion 7. Axis 8
And a supporting portion 9 having The opening surfaces of the inflow duct 3 and the outflow duct 4 are formed so that no recess is formed between each of the ducts 3 and 4 and the side wall of the valve box 2.
Is fitted into the valve box 2 so as to coincide with the side wall surface of the valve case 2.
In addition, when the valve element 6 is pushed up by the air flow, the entire valve element 6 can be stored in the upper part of the valve box 2, and the end of the valve element 6 comes into contact with the upper wall 12 and stops. When
A storage space 13 that positions the end of the valve 6 near the upper end of the outflow duct 4 is formed.

Although the position of the valve shaft 8 moves according to the degree of bending of the support portion 9, the position of the valve shaft 8 is within a range where the opening / closing portion 7 moves toward the outflow duct 4 due to its own weight and does not separate from the inflow port 5. In other words, in other words, the inclination angle of the opening / closing portion 7 when the valve element 6 rotates and stops in a free state with the valve shaft 8 as a fulcrum is larger than the position where the inclination angle of the inflow port 5 coincides. What is necessary is just to be the extension upper side of the opening surface of the inlet 5.

Hereinafter, the moving direction of the valve body 6 according to the position of the valve shaft 8 will be described with reference to FIG.

A vertical line from the valve shaft 8 is indicated by reference numeral 10 and a position of the center of gravity of the valve body 6 is indicated by reference character G.

The center of gravity G of the valve body 6 which rotates about the valve shaft 8 as a fulcrum moves on a perpendicular line 10 from the valve shaft 8 and stops. For this reason, the valve element 6 shown in FIG. 2 has an urging force in the direction of arrow 11, and closes the inflow port 5 in a state where the urging force presses the opening surface of the inflow port 5.

Further, as the supporting portion 9 is bent toward the outflow duct 4, the position of the center of gravity G approaches the vertical line 10, and the urging force of the valve body 6 toward the inflow duct 3 decreases.
When the center of gravity G coincides with the perpendicular 10 from the valve shaft 8, the valve element 6 contacts the opening surface of the inflow port 5 in a state where there is no urging force on the inflow duct 3 side or the outflow duct 4 side. To close the inflow port 5.

When the support portion 9 is further bent so that the center of gravity G is located on the right side of the perpendicular 10, the valve 6
Is rotated from the opening surface of the inflow port 5 toward the outflow duct 4 by its own weight, and the inflow port 5 cannot be closed only by its own weight.

Next, the operation of the above configuration will be described.

When there is no air flow in the inflow duct 3, the valve 6 urges toward the inflow duct 3 by its own weight, and contacts the opening surface of the inflow port 5 to close the inflow port 5. .
On the other hand, when an air flow is generated in the forward direction (arrow A in FIG. 1) that pushes up the valve body 6 in the inflow duct 3, the valve shaft 8 is positioned on the outflow duct 4 side by bending of the support 9. Since the urging force of the valve body 6 toward the inflow duct 3 is small, the valve body 6 is slightly pushed up by the pressure of the air flow with little resistance to the air flow with the valve shaft 8 as a fulcrum. As a result, the airflow from the inflow port 5 of the inflow duct 3 to the outflow duct 4 is allowed. When the flow of air in the forward direction stops or the flow of air in the reverse direction (arrow B in FIG. 1) occurs, the valve body 6 closes the inlet 5 by its own weight, and Prevent backflow.

The valve shaft 8 is arranged such that the valve body 6 is also on the outflow duct 4 side.
When it is provided at a position where it is not biased also on the inflow duct 3 side, that is, the center of gravity G of the valve body 6 is
When it is located above, the valve element 6 is lightly pushed up by the pressure of the air flow without causing the most resistance to the air flow, and the valve element 6 is pushed up as shown by the broken line in the figure with respect to the positive direction air flow that pushes up the valve element 6. State, whereby the inlet 5 of the inflow duct 3
From the outlet duct 4 is allowed. When the flow of air in the forward direction is stopped, the valve body 6 contacts the opening surface of the inflow port 5 and closes the inflow port 5 without having a biasing force on the inflow duct 3 side. When the flow is generated, the valve 6 closes the inflow port 5 in a state of being urged toward the inflow duct 3 by the pressure of the airflow, thereby preventing the backflow of the airflow.

The inflow duct 3 and the outflow duct 4 are
Since the opening surfaces of the ducts 3 and 4 and the side wall of the valve box 2 are fitted so that no concave portion is formed between the ducts 3 and 4 and the side wall surface of the valve box 2, dust and the like in the air flow are removed. It does not flow out of the outflow duct 4 without accumulating in the box 2, and there is no occurrence of rotation failure of the valve element 6 due to accumulation of dust and the like.

When the valve 6 is pushed up by the airflow, the entire valve 6 can be accommodated in the upper portion of the valve box 2, and the end of the valve 6 contacts the upper wall 12. The storage space 13 is formed in which the end of the valve element 6 is positioned near the upper end of the outflow duct 4 when the valve element 6 stops. When the airflow in the forward direction occurs, the valve element 6 is stored in the storage space 13. From the inflow duct 3 to the outflow duct 4 because the opening and closing portion 7 of the valve body 6 forms a flow path for guiding the airflow from the inflow port 5 to the outflow duct 4 without blocking the airflow path. The air flow is good.

[0023]

According to the present invention, a valve box in which an inflow duct having an inclined air inlet at one end and an outflow duct having an air outlet at the other end is inserted, and the opening of the air inlet is extended. A check valve having a valve shaft on the upper side and a valve body that opens and closes the air inlet with the valve shaft as a fulcrum, wherein an upper part of the valve body is bent toward the outflow duct, and the valve shaft is By providing the valve at a position closer to the outflow duct than an extension of the opening surface of the air inlet and in a range in which the valve element is not biased toward the outflow duct, the flow goes from the outflow duct to the inflow duct. When air flow occurs or there is no air flow in the inflow duct, the valve body urges the inflow duct side with a small force by its own weight, and contacts the opening surface of the air inflow port. Closes the air inlet, preventing backflow of the air flow. When air flows in the direction of pushing up the valve body in the inflow duct, the urging force of the valve body toward the inflow duct side is small. Since it can be pushed up lightly without causing the air flow, the capacity of the fan that generates the airflow can be reduced.

By providing the valve shaft at a position where the valve element does not urge the valve body toward the outflow duct side and the inflow duct side, the valve element is provided with the most airflow in the direction of pushing up the valve body. Since it is pushed up lightly without resistance, the capacity of the fan for generating the air flow can be minimized.

By forming one side wall of the valve box so as to be detachable, cleaning, repair and the like in the valve box can be easily performed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a check valve of the present invention.

FIG. 2 is an explanatory diagram of a moving direction of a valve body depending on a position of a valve shaft.

FIG. 3 is a longitudinal sectional view of a conventional check valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Check valve 2 Valve box 3 Inflow duct 4 Outflow duct 5 Inlet 6 Valve body 7 Opening / closing part 8 Valve shaft 9 Support part 10 Vertical line 11 Arrow 12 Upper wall 13 Storage space G Center of gravity

Claims (3)

[Claims] 1. A valve box in which an inlet duct having an inclined air inlet at one end and an outlet duct having an air outlet at the other end are inserted, and an opening of the air inlet is extended. A check valve having a valve shaft on the upper side and a valve body that opens and closes the air inlet with the valve shaft as a fulcrum, wherein an upper part of the valve body is bent toward the outflow duct, and the valve shaft is A check valve, wherein the valve body is provided on the outflow duct side with respect to an extension of an opening surface of the air inlet, and the valve body is provided so as not to be separated from the air inlet by the weight of the valve body. valve. 2. The check valve according to claim 1, wherein the valve shaft is provided at a position where the valve element does not urge the valve body toward the outflow duct and the inflow duct. 3. The check valve according to claim 1, wherein one side wall of the valve box is detachably formed.