JP3495933B2 - Dual plate check valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer type dual plate check valve having two semi-circular disc-shaped valve bodies having corrosion resistance in a main body, and is particularly used for medium and large diameter valves. is there.

[0002]

2. Description of the Related Art Conventionally, two half-disc-shaped valve bodies are urged by springs and are pivotally supported on the main body by one hinge pin, and the valve bodies are normally closed by a spring force. The valve body is biased and held, and the fluid pressure of the normal flow causes the valve element to rotate to the valve open position against the elastic force of the spring to allow the fluid to flow through. A wafer-type dual plate check valve in which the valve element is quickly closed by an elastic force is known, and is disclosed in, for example, Japanese Patent Laid-Open No. 8-166072.

The dual plate check valve disclosed in the above publication, as shown in FIG. 6, has two semi-circular valve bodies 3a and 3b rotatably supported by a main body 1 by hinge pins 2.
Is urged in the valve closing direction (the direction in which the two valve bodies themselves are opened) by the coil spring 4 wound around the hinge pin 2 and having both ends abutting against the back surfaces of the two valve bodies. There is. In the figure, 5 is a stopper pin installed at a position sandwiched between the back surfaces of both valve bodies whose front surface 3c is formed by a part of the spherical surface when the valve is opened, 6 is a flat planar valve seat portion, and 7 is A central rib 8 provided on the upstream side of the hinge pin 2 is a stopper provided on the back surface of both valve bodies, and an elastic cushioning material 8a is projectingly provided at the central portion thereof.

Since it is constructed as described above, the main body 1
When the fluid does not flow in the inside, the two valve bodies 3a and 3b are expanded 180 ° C. by the elastic force of the spring 4 as shown by the solid line, and the pipe line is fully closed. When the fluid flows toward, the two valve bodies 3a, 3b open the conduit as shown by the dotted line against the elastic force of the spring 4, and at the time of the normal flow rate, both valve plates are provided with stoppers at the center. Abut pin 5,
It keeps it fully open. Also, when the water supply in the pipe is suddenly cut off due to an emergency stop of the pump, etc., both valve plates 3a,
3b is designed to act quickly and reliably (valve closing) with spring force to protect the piping system from backflow shock waves (water hammer), and is a small and lightweight check valve with excellent durability and corrosion resistance. is doing.

[0005]

The known dual plate check valve (FIG. 6) as described above has the following problems.

(I) Conventionally, in this type of dual plate check valve, the material of the seat portion of the valve body and the valve seat is a combination of metal and elastic body in order to secure the sealing property and prevent noise. For small / medium bore valves, the mass of the elastic body (volume)
Could not be formed so large that there was a risk of damage to the elastic body such as wear, peeling or dropping.

(Ii) Further, like the hinge pin which is the rotating shaft of the valve element, the main body and the bearing portion which axially support the stopper pin for stopping the valve element at the valve opening position have been in contact with the fluid for many years, Moreover, when the metal valve element comes into contact with the valve when it is fully opened, a metallic noise, an abnormal noise, etc. are generated, and the vibration of the stopper pin causes
There was a risk that the above bearing would be worn or damaged.

(Iii) In the conventional dual plate check valve of this type, since the fluid passages of the hollow cylindrical main body are all made of a metal material and the kinds of fluids are limited, for example, corrosion is caused. There is a problem that it cannot withstand long-term use with fluids such as seawater, sewage, and wastewater, which have a certain property. Further, in recent years, a check valve adapted to a pipe material having corrosion resistance (eg, rubber lining, resin coating, etc.) has not been found.

The present invention solves the above-mentioned problems of the prior art, can withstand the use of various corrosive fluids, and wears two semi-disc-shaped valve bodies when they are closed and when they are fully opened. In addition, it prevents damage and generation of metallic noise, and facilitates reliable centering work until the time of connection with piping, and especially, medium and large diameter (300 to 10
00 A or so) can correspond to corrosive fluids in valves, and it is an object and a long period of time to provide a stable dual plate check valves may be used.

[0010]

[Means for Solving the Problems] The means adopted by the present invention for solving the above-mentioned problems are as follows: the end portion on the inflow side is provided so as to project inward along the inner surface of a cylindrical body and is divided into two at the center. A hollow cylindrical main body made of a rigid material having a semi-annular valve seat portion, a hinge pin having a fluid passage diametrically installed therein, and a hinge pin rotatably supported by the hinge pin to selectively select the fluid passage of the main body. A dual-plate check valve provided with a pair of semi-disc-shaped valve bodies that are opened and closed at the same time and a spring that normally urges the valve bodies in the closing direction, and is attached to the hollow cylindrical body.
Especially for medium and large diameter valves where the seat cannot be molded with a mold,
The pretreated whole inner peripheral surface of the fluid passage of the hollow cylindrical body is elastic.
Sheets made of flexible material are formed at multiple
Lay it by hand without molding it with a mold and crimp it with a roll.
After firmly adhering, put the whole body in the vulcanizer and vulcanize.
An elastic sheet having a predetermined hardness is formed, and a valve seat portion on which the two semi-disc-shaped valve bodies are seated on the seating surface of a semi-circular ring is formed thicker than the cylindrical portion. It is characterized in that the stopper bosses of the two valve bodies when opened are formed of elastic bodies integrally formed on the inner peripheral surface of the main body so as to face each other in the diametrical direction.

Further, a sheet made of an elastic material integrally vulcanized and molded is integrally formed on the entire inner peripheral surface of the fluid passage of the hollow cylindrical body,
It is characterized in that it is formed by bending and extending to the pipe connecting surfaces on the inlet side and the outlet side.

Further, a U-shaped cross section is provided in the vicinity of the hinge pin extension of the reinforcing rib portion formed on the outer side of the piping flange surface at both ends of the hollow cylindrical body in order to facilitate the arrangement of the valve at the time of pipe connection. The grooved pipe bolt positioning rib is formed.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to the examples shown in the drawings. FIG. 1 is a cross-sectional view showing a fully closed state of a dual plate check valve according to an embodiment of the present invention with a solid line and a fully open state with a chain double-dashed line.

In the figure, a hollow cylindrical main body 11 made of a rigid material has a valve seat portion 12 projecting inward along an inner surface of a cylindrical body at an end portion on the inflow side (downward in the figure), and a lower end on the inflow side. It is integrally formed in the shape of a semicircular ring which is divided into two parts by a central rib 13 part which is provided in the central part in the radial direction.

The valve seat portion 12 is rotatably supported by a hinge pin 15 installed across the fluid passage 14 in a diametrical direction, and is normally biased by a spring 16 in a closing direction.
The fluid passage 14 is formed by a pair of semi-disc-shaped valve bodies 17.
Selectively open (two-dot chain line position) or closed (solid line position)
It is supposed to do.

Further, a predetermined sheet 18 (generally 3-5 mm in thickness) made of an elastic material is formed on the entire pretreated inner peripheral surface of the fluid passage 14 of the hollow cylindrical main body 11 without molding with a die. Lay it with free lining (hand lining), press it with a roll to make it adhere more securely, then put the whole body in a vulcanizing pot and vulcanize it at 150 ° C for about 30 minutes to obtain an elastic body with a predetermined hardness. I am trying to get it.

The sheet 18 made of the above elastic material
Is integrally vulcanized and molded on the cylinder inner surface 11a, the pipe flange surface 11b, and the valve seat portion inner surface 12a.
As shown in FIG. 3A, retaining portions 18a, 18b having wedge-shaped (trapezoidal) cross-sections are formed at a plurality of positions, and integrally vulcanization molded. The retaining portion may be formed in a mountain-shaped cross section 18c as shown in FIG. 3 (b).

The portion of the elastic seat 18 on which the valve element 17 of the valve seat portion 12 is seated adheres is thicker than the cylindrical portion 18
It is formed in d. The elastic sheet 18 is formed by bending and extending to the pipe connection flange surface 11b on the upper portion of the cylindrical main body 11. Further, the central rib 13 provided on the inlet side (inflow side) is formed so that the inflow side is tapered in order to reduce fluid resistance.

Further, a stopper boss 19 corresponding to the stopper pin 5 of the conventional example (FIG. 6) with which the back surfaces of the pair of semicircular disc-shaped valve bodies 17 abut when the valve is opened (fully opened) is located above the hinge pin 15. It is configured by a convex elastic body integrally formed at a position on the inner peripheral surface of the main body so as to be opposed to each other in the diametrical direction.

On the other hand, the reinforcing ribs 11c integrally formed outside the pipe flange surfaces 11b at both ends of the hollow cylindrical main body 11 are provided near the extension of the hinge pin 15, that is, near the base of the stopper boss 19. As shown in FIG. 2, a groove-shaped recess having a U-shaped cross section is extended outwardly at a symmetrical position with respect to the center O of the valve body, that is, a diametrical eye passing through the center O of FIG. Positioning ribs 21 of the two piping bolts 20 arranged side by side so as to match the pitch of the piping bolts 20 are integrally formed on the line. FIG. 2 shows a state in which the two pipe bolts 20 are fitted in the recesses of the positioning ribs 21, which facilitates reliable centering when the check valve is installed in the pipe. become.

After the check valve main body and the pipe have been centered by setting the two locations in the diameter direction in this way, the remaining pipe bolts 20a ... By inserting and fastening the pipe flanges facing each other on both sides, the installation work can be easily completed, and the labor and required time can be saved.

FIG. 4 is a detailed view of the upper hinge pin portion in FIG. 2, in which 17a is a boss portion of the valve body 17, 22 is a bearing of the hinge pin 15, and 23 is a plug.

FIG. 5 is a plan view of FIG. 4, in which
Reference numeral 11d is an outer peripheral surface of the main body 11, and 11e is an end portion of the main body 11.

The present invention is a medium / large-diameter valve that cannot be mass-produced and mass-produced like a small / medium-diameter valve, and is CR (neoprene) in view of fluid compatibility and pipe lining according to user requirements. Adhesion of sheet raw rubber (before vulcanization) such as NBR (nitrile rubber) and EPEM (ethylene / propylene rubber) after degreasing and rinsing the inner surface of the main body without using a mold By applying a raw rubber paste (referred to as a co-paste of the same material as the attached rubber) and then applying the adhesive and vulcanizing it, the physical properties are improved and the adhesion is improved. And due to the negative pressure phenomenon due to the local pressure fluctuation due to the dynamic flow of the fluid as in the present invention, the means for preventing the lining sheet portion formed as described above from coming off due to peeling becomes an important requirement, and Wedge-shaped (trapezoidal) shape on the back side of each sheet to prevent resistance to the flow of fluid
The retaining portions 18a to 18c are integrally formed at a plurality of locations.

Next, the operation will be described. As in the above-mentioned conventional example (FIG. 6), mainly the small / medium caliber (50 to 300) is used.
(About A), the seat ring is attached or inserted into the main body, but as in the present invention, it has a medium or large diameter (300 to 1).
000A), the cost is high due to the relationship of the mold and the number of products to be produced, and it is said that it is impossible to manufacture. Therefore, it is integrally vulcanized and molded after free lining (hand lining) as described above. However, when the valve is opened by the dual plate check valve, the valve seat portion 12 is contracted, so the flow velocity becomes high when passing through the portion, and the secondary side (downstream side) becomes a turbulent flow region and the lining sheet 18 peels off. However, in the present invention, since the wedge-shaped or groove-shaped retaining portions 18a to 18c are formed at a plurality of positions on the back surface of the lining sheet, the passage surface can be removed without forming any resistor. Stop prevention can be effectively performed.

Further, since the elastic seat portion 18 is formed so that the seating surface of the valve seat portion 12 has a particularly thick wall 18d, the valve body 17 is highly durable against repeated contact.

On the other hand, as a stopper at the time of full opening, a small / medium diameter valve (FIG. 6) often uses a stopper pin 5 of the same kind as the hinge pin 2, but a medium / large diameter valve as in the present invention has a heavy weight. In an increased and unstable state (the valve body opens and closes at a small opening = chattering), there is noise due to the vibration of the stopper pin, and as a result, the bearing portion of that part expands and rattles,
Again, the stopper boss 19 formed of a convex elastic body projecting diametrically opposite each other on the inner peripheral surface of the main body is used because of its strength and the role of a cushioning material. Such fears can be resolved.

Further, even in the medium- and large-diameter valve as in the present invention, a gasket is required at the time of connecting the pipes, and this is one of the difficult tasks to insert the gasket at the time of installation because of its cost. The reason is that the width of the gasket is relatively small, and fixing the gasket to the portion requires labor and time. In particular, recently, it is necessary to reduce the total cost, and work efficiency and the like are important factors. However, in the present invention, the elastic sheet 18 is used as the pipe flange surface 11
Since it is bent and extended to b, the above-mentioned inconvenience in labor and workability is eliminated.

Similarly, the disposition of heavy objects for medium- and large-diameter valves as in the present invention has the same problems of labor and workability as described above.
In a flangeless type valve, it can be said that it is difficult to arrange the valve coaxially with the pipeline, especially in a medium / large diameter valve. Therefore, a positioning rib for arranging swiftly and accurately is a necessary constituent element, but in the present invention, by setting two diametrical points such as the EE line passing through the center O in FIG. Therefore, the core of the valve is the same as that of the pipe, and by setting the bolt 20a in the other portion, the accurate disposition work can be easily completed.

Further, by forming the shape of the positioning portion with respect to a heavy object in a groove-shaped recess whose upper portion is opened, if the hole-shaped bolt insertion portion is assumed, the upper surface portion of the hole is inserted. In addition, there is no strength concern that the bolt will be damaged due to lifting or the like, the bolt insertion portion is not processed, and the valve can be slid and inserted from the lateral direction at the time of installation, resulting in good work efficiency.

In the above-described embodiment, the positioning rib 21 shown in FIG. 5 is provided at the substantially central portion of the peripheral surface 11d of the main body.
1 may be biased toward the body end 11e.

[0032]

As described above, according to the present invention,
A hollow cylindrical main body made of a rigid material having a semi-annular valve seat portion projecting inward along the inner surface of the cylindrical body at the end on the inflow side and separated into two in the center, and a fluid passage in a diametrical direction. And a pair of semi-disc-shaped valve bodies that are rotatably supported by the hinge pins and selectively open or close the fluid passage of the main body, and the valve bodies are always closed. In a dual-plate check valve with a spring that biases in the direction, the seat to be attached to the hollow cylindrical body is especially molded.
For medium / large diameter valves that cannot be molded,
The entire pre-treated inner surface of the fluid passageway has a sheath made of an elastic material.
Do not mold the mold by forming retaining parts at multiple locations.
Laid by hand and crimped with a roll to ensure a tight fit
After that, put the whole body in the vulcanization pot and vulcanize it,
A body seat, and a valve seat portion on which the above-mentioned two semi-disc-shaped valve bodies are seated on the seating surface of a semi-annular ring of the seat is formed to be thicker than the cylindrical portion, and two sheets are provided when the valve is opened. Since the stopper boss of the valve body is formed of the elastic body integrally formed on the inner peripheral surface of the main body so as to face the diametrical direction, the following effects can be obtained.

(I) A medium / large-diameter valve that can be used for various corrosive fluids.

(Ii) Especially for medium- and large-diameter valves, it is not molded in a mold, and a predetermined sheet is formed by free lining (hand lining) to prevent slip-off at a plurality of places of the sheet and integrally vulcanized into the main body. Therefore, the elastic sheet material does not peel off even when the valve is opened.

(Iii) Since the seat of the valve seat portion on which the pair of disc-shaped valve bodies are seated is formed thick, the sealing property is great, and stable use is possible for a long period of time.

(Iv) In the fully opened state, the conventional stopper pin is replaced by a convex elastic body integrally formed on the inner circumferential surface of the main body so as to face each other in the diametrical direction. it is possible to achieve a reduction cutting weight and.

Further, since the sheet made of the elastic material integrally vulcanized and molded on the entire inner peripheral surface of the fluid passage of the hollow cylindrical main body is bent and extended to the pipe connecting surfaces on the inlet side and the outlet side, The effect like is produced.

(I) The material (gasket) at the time of installation can be saved, the labor and time required for installation work can be saved, and the total cost can be reduced.

(Ii) A reliable sealing property at the pipe flange portion is possible.

(Iii) Since the elastic sheet portions bent and extended to the inlet-side and outlet-side pipe connecting surfaces are sandwiched between the flanges at the time of installation, the elastic sheet portions of the cylindrical portion are extended in the inner diameter direction. Peeling is prevented.

Further, a U-shaped cross section is provided in the vicinity of the hinge pin extension of the reinforcing rib portion formed on the outer side of the pipe flange surface at both ends of the hollow cylindrical main body to facilitate the arrangement of the valve at the time of pipe connection. By forming the grooved pipe bolt positioning ribs, it is possible to facilitate reliable centering at the time of installation, greatly reduce the labor and time of installation work, and reduce the total cost. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a fully closed state (solid line) and a fully opened state (two-dot chain line) of a dual plate check valve according to an embodiment (example) of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a partially enlarged sectional view of a portion A in FIG. 1, where (a) and (b) show different embodiments.

FIG. 4 is a partial detailed view of the upper hinge pin portion of FIG.

FIG. 5 is a plan view of FIG.

FIG. 6 is a cross-sectional view of a dual plate check valve showing a conventional example.

[Explanation of symbols]

11 body 11a inner peripheral surface 11b Piping flange surface 11c Reinforcing rib 11d Main body outer peripheral surface 11e Body end 12 valve seat 13 Central rib 14 fluid passage 15 Hinge pin 16 springs 17 valve body 17a Valve body boss 18 Elastic sheet 18a, 18b, 18c retaining part 18d Thick part of valve seat 19 Stopper boss 20, 20a Piping bolt 21 Positioning rib 22 Bearing B Inflow side inner diameter C Outflow side inner diameter

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 10-220604 (JP, A) JP 10-292874 (JP, A) JP 10-196804 (JP, A) JP 8- 166072 (JP, A) JP-A-7-145869 (JP, A) JP-A-8-145196 (JP, A) JP-A-10-281314 (JP, A) Actually developed 61-148968 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16K 15/00-15/20 F16K 27/00-27/12

Claims (3)

(57) [Claims] 1. A hollow cylindrical main body made of a rigid material having a semi-annular valve seat portion projecting inward along an inner surface of a cylindrical body at an end portion on an inflow side and divided into two in the center, A hinge pin installed across the fluid passage in a diametrical direction; a pair of two semi-disc shaped valve bodies rotatably supported by the hinge pin to selectively open or close the fluid passage of the main body; In a dual plate check valve equipped with a spring for urging the valve body in the closing direction at all times, a seal attached to the hollow cylindrical body is used.
Is designed for medium- and large-diameter valves that cannot be molded with a mold.
Elasticity is applied to the entire pretreated inner peripheral surface of the fluid passage of the hollow cylindrical body.
Form the retaining parts at multiple locations on the sheet of material
Lay it by hand without forming it with a mold and crimp it with a roll to make sure.
After actually adhering, place the whole body in the vulcanizer and vulcanize.
An elastic seat having a constant hardness, and a valve seat portion on which the two semi-circular valve bodies are seated on the seating surface of the semi-annular ring of the seat,
It is formed to be thicker than the cylindrical portion, and when the valve is open, the stopper bosses of the two valve bodies are formed of elastic bodies integrally formed on the inner peripheral surface of the main body so as to face each other in the diametrical direction. Dual-plate check valve that does. 2. A sheet made of an elastic material integrally vulcanized and molded on the entire inner peripheral surface of the fluid passage of the hollow cylindrical main body is bent and extended to the pipe connecting surfaces on the inlet side and the outlet side. The dual plate check valve according to claim 1. 3. A U-shaped cross section is provided in the vicinity of the hinge pin extension of the reinforcing rib portion formed on the outside of the piping flange surface at both ends of the hollow cylindrical main body to facilitate the installation of the valve at the time of pipe connection. The dual plate check valve according to claim 1 or 2, wherein the grooved pipe bolt positioning rib is formed.