JPH09210227A - Check valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent noise generation and damage of a valve unit caused by fluttering of the valve unit relating to a stopper determining a fully-opened position of a check valve. SOLUTION: In this constitution, a lock protrusive streak 31 moved together with a valve unit 2 is extended onto the periphery of a valve shaft 5, a lock protrusive streak 41 fixed to a valve casing 1 not to move is also slidably extended by spacing an angle onto a peripheral surface of the same range to the valve shaft, and when a valve is fully opened, an angle, formed when both the lock protrusive streaks into contact by side surfaces 32, 42 are separated at valve fully closed time, is freely adjusted from the outside of the valve. In a pipe line, when a steady flow is generated, the valve unit is pressed by flow energy to be moved, the pipe line is fully opened, when the side surface 32 of the lock protrusive streak turned with the valve unit is brought into contact with the side surface 42 of the unmoved lock protrusive streak, the valve unit is stopped. Contact with the fellow side surfaces attains a stopper function, so that repetition of an excessive shock and generation of a noise can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a check valve, and more particularly to improvement of a stopper function when the check valve fully opens the valve in a steady flow.

[0002]

2. Description of the Related Art A check valve is attached mainly to the outlet side of a pump in an industrial fluid pipeline such as building equipment, waterworks, and sewers, and the valve element allows water to flow while the fluid is being constantly sent. It is opened by the flow force, but when something abnormal or need for repair occurs in the pipeline and water flow from the upstream side stops or the water pressure drops, immediately close the valve and start from the downstream side. To prevent backflow of

In order to achieve this purpose, the check valve is required to have a valve body which is constantly pushed by a flow force to open and a structure which automatically closes the valve body when the flow force is lost or attenuated. Although these types have been put into practical use as publicly known technology, the main types are roughly classified into the following two types. One of them is a dual plate type check valve, and a typical shape thereof is, as shown in FIG. 5, two valve bodies 102 housed in a wafer type valve box 101 and opened and closed by a common valve shaft 105. It is a composition. Connected to the pump outlet side in the fluid conduit and normally the valve body is opened by being pushed by the fluid flow force, but before the backflow from the downstream side occurs when the pump stops and the flow force decays. In addition, the urging force of the elastic spring 106 that urges in the valve closing direction acts to fully close the valve body 102 and suppress the occurrence of water hammer. The elastic spring 106 is configured so as to bend and open the flow path when a fluid pressure is received around the axis of the valve shaft 105.

In the dual plate type check valve, the valve element is normally opened by being pushed by the flow force, but the stopper 1 is provided in the valve box so that the stop position at the time of full opening is specified so that the two do not collide.
It is set so that when the valve body 07 is laterally stretched and is pressed by the flow force, the valve body rotates against the biasing force of the elastic spring and the valve body surface hits the stopper 107 and stops at this position. In addition,
The check valve often has a built-in bypass flow passage for draining water or for priming the pump. In the example of this drawing, the bypass flow passage 111 is provided by perforating the valve box.
2 is attached and the function to open and close the bypass channel is added when necessary.

Another type of check valve that is often used is a general swing type. As shown in FIG. 6, a single valve body 202 flows in a valve box 201 via an arm 207 by a valve shaft 205. It is unilaterally suspended from one side of the passage, and is pushed by the flow force during a steady flow and naturally swings around the valve shaft 205 as a fulcrum to open the flow passage, and the flow force on the upstream side is lost or lost. If it does, it behaves in accordance with the principle that the flow path is naturally returned to close the flow path. Even in this case, the limit when the valve is fully opened,
That is, since a stopper for rotating the valve element is required, in the prior art shown in the figure (Japanese Utility Model Laid-Open No. 61-70662),
The screw rod 206 is projected into the valve box, and when the arm 207 supporting the valve element comes into contact with the tip of the screw rod 206, the rotation is stopped and the fully opened position is specified. In the swing type check valve, many proposals basically include a stopper of this type. For example, in the prior art of Japanese Utility Model Laid-Open No. 58-153767, the arm 307 has a threaded rod 306 as shown in FIG.
The configuration that controls the posture when the valve is opened is presented.

[0006]

It is one of the important management items to identify the position of the valve body and control the posture when the valve is opened, which leads to the control of the flow rate in the pipeline and also affects the flow velocity. Is. In addition, there are cases where it is necessary to adjust the position when fully opened due to fluctuations in the fluid, and it is often required from the outside to have a function of adjusting the posture of the valve body when fully opened. However, from this point of view, in the conventional technique (dual plate type) of FIG. 5, since the rod-shaped stopper 107 is simply installed laterally at a predetermined position in the valve box 101, the position of this stopper is changed. It is impossible to change it easily from the outside after installing it in the pipeline. In order to change it, it is necessary to remove the valve box from the pipe line and attach the stopper again, so that the specifications cannot be easily changed according to changes in fluid.

On the other hand, from a structural point of view, when the fluctuation of the flow velocity or the turbulent flow occurs in the fluid in the valve box, the valve body flutters and flaps, and the stopper 10 is in contact.
Since it collides with and separates from 7, it is inevitable that repeated impacts will be generated and impact noise will be generated. If such an unstable shock is repeated for a long time, the striking force will naturally accumulate on the stopper itself, the valve body, and the valve box, causing damage, wear, metal fatigue, etc., and deterioration of the valve function. There are also concerns that may cause malfunctions.

Further, since the stopper in the swing type check valve shown in FIGS. 6 and 7 can adjust the projection depth into the valve box by advancing and retracting the screw, the stop position when the valve body is fully opened is determined by the fluid. It can be adjusted according to the mode. However, for example, as shown in FIG. 6, the principle is that the screw rod 206, which is a stopper, abuts on the arm 207. Therefore, the radius of rotation from the shaft center becomes large, and the rotational movement distance between fully closed and fully opened is large and energy is also increased. Since it becomes large, the impact contact surface pressure at the time of full-open contact is inevitably large, and the possibility of damaging the contact surface cannot be denied. Further, since the valve body 202 rotates about the axial center of the valve shaft with respect to the screw rod 206 mounted vertically, it acts as a bending stress on the screw rod 206 to bend the screw rod in a direction. If force acts and deforms, there is a concern that the position of the opening may change without knowing and the predetermined flow rate may increase or decrease.

In order to solve the above-mentioned problems, the present invention can not only freely control the fully open position of a check valve that is generally put to practical use from the outside, but also the member that specifies the position can flow. The purpose of the present invention is to provide a check valve that does not suffer from a heavy load even when subjected to fluctuations in power and does not generate impact noise, and always guarantees a highly reliable valve function.

[0010]

In the check valve according to the present invention, the valve element 2 axially supported in the valve box 1 is pushed by the flow force to open in the steady flow, and immediately operates in the valve closing direction in the reverse flow. A locking ridge having a basic structure having a function is provided to extend on the outer circumference of the valve shaft so as to move together with the valve body 2, and the locking ridge that is fixed to the valve box and does not move has the same range of the valve shaft 5. It is slidably extended at an angle on the outer peripheral surface of the valve, and both of the locking projections that abut against each other when the valve is fully open are formed separately when the valve is fully closed. What is done is a feature of the configuration.

The valve body 2 is pivotally supported by the valve shaft 5 to rotate to open and close the conduit. With this rotation, the valve body 5 extends over the outer peripheral surface so as to cover a certain area of the valve shaft 5. The stop ridges also rotate at the same angle. On the other hand, there is an immovable locking ridge fixedly extended to the valve box 1 on the circumference of which the angle is changed within the same range on the outer peripheral surface of the valve shaft, and the valve shaft 5 has an inner circumference of this locking ridge. Insert the surface. When the flow force in the pipe is attenuated, the valve closing function works and the valve element pivotally supported by the valve shaft rotates while sliding with the immovable locking ridge and rotates by the set angle. To close the valve body to close the pipeline. When the flow in the pipe is restored to its original condition, the valve is rotated by the flow to start opening the pipe, and the side of the locking ridge that rotates with the valve is fixed. When it comes into contact with the side surface of the ridge, further rotation is blocked and it stops at that position. Since the rotation angle between the valve opening and the valve closing can be freely adjusted from the outside, it means that the position of the valve body when the check valve is fully opened can be freely adjusted as required, and both locking projections Since the contact between the side surfaces of the two fulfills the stopper function, the above problems can be solved all at once without the repetition of excessive impact and the generation of noise as in the prior art.

In the above-mentioned structure, specifically, the check valve is a dual plate type check valve. Specifically, the two valve bodies 2 are constantly urged by the elastic spring 6 in the valve closing direction, The body 2 has the locking ridge 31 extending from the valve body boss 3 into which the valve shaft 5 is fitted, and is engaged with the valve bearing seat 4 fixed to the valve box 1 at the same angle on the outer circumference of the valve shaft. It is characterized by a configuration in which the stop projection 41 is extended.

Alternatively, the type of the check valve is a swing type check valve, and the valve body 2A is axially supported by the valve shaft 5A via the arm 7 at an unbalanced position so that the valve body 2A always swings in the valve closing direction. Valve shaft 5
The locking projection 71 extends from the arm 7 into which A is fitted, and is opposed to the locking projection 41A extending from the valve bearing seat 4A at the same angle on the outer circumference of the valve shaft in the same range. The same is true.

When the check valve is a dual plate type,
When the valve is closed, the angle formed between the locking projections 31 and 41 is adjusted by screwing a screw thread 43 on the end of the valve bearing seat 4 and advancing and retracting the screw hole 14 that horizontally penetrates the valve housing 1. Screw freely,
Further, it is a preferred embodiment that the lock nut 44 is screwed to the end portion where the screw thread 43 is exposed outside the valve box.
That is, if it is necessary to adjust the angle, the lock nut 44
And the screw thread 43 of the valve bearing seat is moved forward or backward to change the relative angle at which the valve bearing seat is fixed in the valve housing 1. Therefore, the valve bearing seat is easily formed between fully open and fully closed. This is because it is possible to control the position of the valve body when fully opened by adjusting the angle θ from outside the valve box.

When the check valve is a swing type, the angle formed between the locking projections 71 and 41A when the valve is closed is adjusted by threading a thread 43A on the end of the valve bearing seat 4A. It is a preferred embodiment that the valve nut 1A is screwed into a screw hole 14A that horizontally penetrates the valve casing 1A so as to be able to advance and retreat, and that the lock nut 44A is screwed to the end portion where the screw thread 43A is exposed to the outside of the valve casing. In this way, since it is a technical idea that it can be applied to any check valve that is the most generalized one without any change, it can be applied to almost all check valves with a slight design change. It is directly connected to the solution of practical problems.

[0016]

1 is a plan view (A) showing an embodiment of the present invention and an XX sectional view (B) thereof, and FIG. 2 is a YY sectional view of the same. Further, FIG. 3 is a sectional view taken along line ZZ in FIG. 1 (B), and FIG. 3 (A) shows that when the valve body is fully closed,
FIG. 6B shows the valve element when it is fully opened, and shows the variation in the relative positional relationship between the two locking projections.

This embodiment is applied to the dual plate type of the check valve, and in the figure, a combination of a wafer type cast valve box 1 and two cast valve bodies 2 is adopted. However, other aspects, that is, a valve box formed by sheet metal forming of a steel plate, a valve body may be used, and the material is not particularly limited to cast iron-based, cast steel-based, stainless steel-based metal or resin valves. , All of the current check valves are generally applicable. As a form illustrated here, a valve corresponding to a valve bearing seat 4 for rotatably rotatably supporting a valve shaft 5 inserted in a wafer type valve box 1 and a portion for fitting the valve shaft 5 of a valve body 2 therein. The backflow prevention function is achieved by combining the respective members of the elastic spring 6 which is mounted on the outer circumference of the body boss 3 and the valve shaft 5 and engages with the valve body surface and always urges in the valve closing direction. Needless to say, this is within the scope of the known art.

As a constitution peculiar to the present invention, a part of the valve bearing seat 4 which is fixed to the valve box 1 and rotatably supports the valve shaft 5 projects toward the center side of the valve body and is a locking ridge. 41 is in surface contact with the outer peripheral surface of the valve shaft, and there is a locking projection 31 protruding from the valve body boss 3 to the outer peripheral surface of the valve shaft in the same range overlapping this contact range. The locking ridges have the relative positional relationship shown in FIG. FIG. 3 (A) shows a state in which the valve body is closed, and the two locking projections are the same with an arcuate gap C of about ¼ circle so that the side surfaces 32 and 42 form a substantially right angle. It is located on the valve shaft 5. When the flow force is restored to a steady flow and the valve body 2 is rotated by the flow force, the locking ridge 3 moves in the counterclockwise direction as viewed in the direction of the arrow (A).
Since 1 rotates in the same direction, the arcuate clearance C is reduced, and finally the side surface 32 of the locking projection 31 comes into contact with the side surface 42 of the locking projection 41 of the stationary valve bearing seat 4 to create the arcuate clearance C. To zero,
At this position, rotation of the valve element is blocked and the valve stops in the fully opened state.

In this dual plate type check valve, the position of the valve element when the valve is fully opened changes the position where the locking ridges 31, 41 contact, that is, the angle formed by the side surface of the locking ridge 41. It can be adjusted freely. In the embodiment shown in FIG. 1, a right-handed screw thread 43 is threaded on the end of the valve bearing seat 4, and the valve bearing seat is fixed by a lock nut 44 screwed outside the valve box. To change the valve body position by adjusting the flow rate when fully opened, loosen the lock nut 44 and
3 is rotated in the screw hole 14 that horizontally penetrates the valve box,
The angle of the side surface 42 of the locking projection 41 with respect to the horizontal plane changes, and the rotation angle of the valve body 2 from fully closed to fully open can be easily increased or decreased by an external operation. For example, FIG.
If the rotation angle is set to an angle θ that is slightly smaller than a right angle so that the arcuate gap C is slightly smaller than the accurate 1/4 circumference as shown in FIG. The contact force between the side surfaces increases to a pressed state, which leads to maintaining a stable valve body position. At the same time, the locking ridge 31 of the valve boss abuts the locking ridge 41 of the valve bearing seat on the screw thread 43, and an external force is applied to rotate the screw boss 31 to the left as viewed from the inner surface of the valve box. If the mountain 43 is set as a right-handed twist so that the external force can be tightened freely with respect to the screw thread, the fully open position once set is always immovable, and the reliability of maintaining the function is kept high.

As in this embodiment, in the dual-plate type check valve, the bypass passage 11 is formed by processing, and the bypass valve 12 is attached and opened / closed as necessary. Even if the structure is not built in, there is no change in the requirements for satisfying the functions of the present invention. In addition, the O-ring 13, the plug 45, the pressing ring 46, the collar 33, and the like are attached to configure the function as a valve, as in known techniques.

Also in the case of the swing type, which is the other main type of the check valve, the positions and shapes of the valve shaft, the valve body boss, and the valve bearing seat, which are known in the art, are different, and the check valve is movable from the valve body side. The locking projection of and the locking projection that is immovable from the valve box side face each other in the same range at a specific angle on the outer peripheral surface of the valve shaft,
There is no change in the gist of the present invention in which the arc-shaped gap formed between the side surfaces of the two increases and decreases as the valve body rotates, and the position where both side surfaces abut determines the fully open position of the valve. FIG.
(A) and (B) show a swing type embodiment, in which the valve shaft 5A is unbalanced via the arm 7 in the valve box 1A.
The valve body 2A pivotally supported by the valve is fully opened by being pushed by the flow force against a steady flow, but when the flow force is reduced, the valve body is closed by its own weight as shown in the figure. The valve body boss 3 in the embodiment of FIG.
Instead of the arm 7, a locking projection 71 extends from the arm 7 onto the outer circumference of the valve shaft 5A, and is fixed to the valve box in the same area as the valve seat 4A.
It is opposed to the locking ridge 41A extending from the base plate with an arcuate gap C therebetween. After all, the action is exactly the same if the positions 31, 32 are replaced by 71, 72 in the positional relationship shown in FIGS. 3 (A) and 3 (B), except for the difference in the original type of the check valve. There are no different requirements. In addition, FIG.
(B) shows the case where there is one valve body, but when there are a plurality of valve bodies, the locking ridges are provided on the boss portion of each valve body, and the corresponding locking ridges are immovable on the corresponding valve bearing seats. Is provided and fixed to the valve box.

[0022]

As described above, the check valve according to the present invention is
Since the position of the valve element in the fully open state can be changed as appropriate, after mass production and manufacturing with the same specifications, individual valves can be used to match specific conditions such as the flow and flow rate peculiar to the actual site of use. Fine adjustment of the product is possible, and it is highly adaptable to adjust to the optimum conditions at each site and place it in the pipeline.

Further, since the contact portion at the fully open position corresponds to the valve body boss portion, the radius of rotation from the center of the valve shaft is small, and compared with the contact near the tip portion of the valve body as in the prior art, the rotation distance is smaller. Significantly shortened. Naturally, since the impact energy at the time of contact is also small, the repeated impact force exerted on the stopper itself, the valve body, the valve box, and other members is greatly reduced, and the impact sound is soothed that it is hardly heard.

All of the stoppers of the prior art are provided so as to cross the flow passage in the valve box, and have a resistance to impede the flow force. However, in the case of the model of the present invention, the cause of the resistance of the flow passage is completely eliminated. There is no risk of damaging the material such as abnormal wear, abnormal corrosion, stress corrosion cracking due to cavitation when viewed from the side of the member, and there is no risk of pressure loss. The effect of maintaining the function for a long time is remarkable.

Since the arcuate clearance C can be reduced by a simple operation of rotating the screw thread of the valve bearing seat as in claims 4 to 5, the valve body can be stopped when the valve body is fully opened. It is also easy to set the angle of θ to a preset angle θ which is slightly smaller than the right angle. By adjusting the angle small, the abutment of both locking projections is strengthened and stabilized, preventing fluttering due to flow velocity change and turbulence in the pipeline, spurring damage prevention of related parts and acoustic suppression The effect of multiplying is also obtained.

[Brief description of drawings]

FIG. 1 is a plan view (A) showing an embodiment of the present invention and a sectional view (B) taken along the line XX in the same figure.

FIG. 2 is a sectional view taken along line YY in FIG.

FIG. 3 shows a positional relationship between a valve closed time (A) and a valve opened time (B) of a main part of the ZZ cross section in FIG. 1B.

FIG. 4 is a plan view (A) and a vertical sectional front view (B) showing another embodiment of the present invention.

FIG. 5 is a vertical sectional front view (A) and a partial cross-sectional side view (B) of a conventional technique.

FIG. 6 is a vertical sectional view of another prior art showing a valve closed (A) and a valve open (B).

FIG. 7 is a vertical sectional front view of still another conventional technique.

[Explanation of symbols]

 1 Valve Box 2 Valve Body 3 Valve Body Boss 4 Valve Bearing Seat 5 Valve Shaft 6 Elastic Spring 11 Bypass Flow Path 12 Bypass Valve 31 Locking Protrusion (Movable) 32 Side 41 Locking Protrusion (Fixed) 42 Side 43 Thread C Arc-shaped gap θ Setting angle

Claims (5)

[Claims] 1. A check valve having a function in which a valve body 2 axially supported in a valve box 1 is pushed by a flow force in a steady flow to open a flow path and is immediately actuated in a valve closing direction in a reverse flow, A locking ridge that moves together with the valve body 2 is extended on the outer circumference of the valve shaft, and fixed locking ridges are fixed to the valve box, and the locking ridge is also fixed on the outer peripheral surface of the valve shaft 5 in the same range. A non-return valve, which is slidably extended, and in which both locking projections, which abut against each other when the valve is fully opened, are formed separately when the valve is fully closed. . 2. The check valve according to claim 1, wherein the check valve is a dual plate type check valve, the two valve bodies 2 are always biased in the valve closing direction by an elastic spring 6, and the valve body 2 drives the valve shaft 5 to move. The locking projections 31 extend from the valve body boss 3 to be fitted therein, and the locking projections 41 extend from the valve bearing seat 4 fixed to the valve box 1 in the same range on the outer circumference of the valve shaft at an angle. Check valve characterized in that 3. The check valve according to claim 1, wherein the check valve is a swing-type check valve, and the valve body 2A is pivoted by the valve shaft 5A via the arm 7 at an unbalanced position so as to always swing in the valve closing direction. Supported by
The locking projection 71 extends from the arm 7 into which the valve shaft 5A is fitted and faces the locking projection 41A extending from the valve bearing seat 4A on the outer circumference of the valve shaft in the same range at an angle. Check valve characterized by. 4. The valve box 1 according to claim 2, wherein the angle formed between the locking projections 31 and 41 when the valve is closed is adjusted by threading a screw thread 43 on the end of the valve bearing seat 4. Is screwed into a screw hole 14 that horizontally penetrates through the
The check valve is characterized in that the lock nut 44 is screwed to the end exposed to the outside of the valve box. 5. The adjustment of the angle formed between the two locking projections 71, 41A when the valve is closed according to claim 3, wherein a thread 43A is screwed into the end of the valve bearing seat 4A to form the valve box 1A. Is screwed into a screw hole 14A that horizontally penetrates the valve nut so that the screw thread 43A is exposed to the outside of the valve box.
A check valve characterized in that 4A is screwed on.