JP2015224490A - Float-type check valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a float-type check valve that increases valve closing force of an annular valve seat by using a float while suppressing a drain water flow from being blocked.SOLUTION: A float-type check valve comprises an annular valve seat, a plurality of floats, guide members and a regulation member. The annular valve seat opens in the vertical direction and communicates the upstream side and the downstream side of a drainage system. The plurality of floats are positioned on the downstream side of the lower side of the annular valve seat so as to be movable in the vertical direction, and are arranged vertically. The guide members guide the vertical movement of the plurality of floats. The regulation member regulates a lower limit position of the movement of the plurality of floats. The plurality of floats includes: a first float which floats upward as a drain water level rises, fits into the opening and closes the same to block the annular valve seat, and falls downward as the drain water level descends, releases the opening and opens the annular valve seat; and a second float which is positioned below the first float and floats upward and falls downward as the drain water level changes.

Description

  The present invention relates to a float-type backflow prevention valve disposed in a drainage system that discharges wastewater generated in a site such as a factory or in a building to a river, the sea, a public drainage facility, or the like.

  Conventionally, in the drainage system that discharges wastewater generated in the premises of factories and buildings to rivers, seas, public drainage facilities, etc., a float type that prevents backflow to drain in the forward direction from upstream to downstream A backflow prevention valve is provided (see, for example, Patent Document 1).

  In general, the float type check valve includes an annular valve seat that communicates the upstream side and the downstream side of the drainage system, a float that is positioned below the annular valve seat, and a plurality of guide members that guide the float vertically. It has. The float floats and descends with the level of drainage to open and close the annular valve seat. Since the water level is low at normal times, the float descends and is placed (landed) on the bottom plate below the annular valve seat, and the annular valve seat is opened. Therefore, drainage is performed in the forward direction from the upstream to the downstream through the annular valve seat. On the other hand, since the water level rises at the time of reverse flow, the float is floated and the annular valve seat is closed. Thereby, the backflow to the upstream side from the annular valve seat is prevented.

  It is desirable that the float described above has a spherical shape so that it can be easily fitted to the annular valve seat in any orientation. Further, since the float is intended to close the annular valve seat, it is generally used alone.

Japanese Utility Model Publication No. 6-67588

  As described above, the float uses buoyancy to close the annular valve seat when the drainage flows backward, but if the buoyancy is weak, the annular valve seat may not be completely closed. Therefore, it is desired to make the float closing force stronger. Therefore, it is conceivable to increase the float's outer diameter (increase the volume) to increase the float's buoyancy. However, since the float type check valve is installed in the drain pipe, etc., if the float is too large, Obstruct the flow.

  An object of the present invention is to provide a float type backflow prevention valve which aims to increase the closing force of an annular valve seat by a float while suppressing the flow of drainage.

  The float type check valve provided in the drainage system for draining from upstream to downstream provided by the present invention includes an annular valve seat, a plurality of floats, a guide member, and a defining member. The annular valve seat opens in the vertical direction and communicates the upstream side and the downstream side of the drainage system. The plurality of floats are positioned so as to be movable in the vertical direction on the downstream side below the annular valve seat, and are arranged side by side in the vertical direction. The guide member guides the vertical movement of the plurality of floats. The defining member defines a lower limit position of movement of the plurality of floats. Further, the plurality of floats float as the drainage water level rises, close the opening by fitting into the opening and closing the annular valve seat, and descend as the drainage water level falls. A spherical first float that opens the annular valve seat by releasing the opening, and a second float that is located below the first float and floats and descends as the water level of the drainage changes. Including.

  The second float may have the same spherical shape as the first float.

  The second float may have a cylindrical shape whose outer diameter is the same as the outer diameter of the first float, whose upper end faces the first float and whose lower end faces the defining member.

  According to the present invention, the first float is pushed upward during the reverse flow, so that not only its own buoyancy but also the upward contact force by the second float that rises is added to the first float. Thereby, the closing force of the annular valve seat by the first float increases as compared with the configuration using a single float. Moreover, it is not necessary to enlarge the first float for closing the annular valve seat. Therefore, it is possible to increase the closing force of the annular valve seat by the first float while suppressing the flow of the drainage.

It is sectional drawing of the backflow prevention valve which concerns on Example 1 of this invention. It is the figure which looked at the state which attached the annular valve seat and the valve-seat retainer to the main body of the backflow prevention valve from the downstream. It is a top view of the baseplate of a backflow prevention valve. It is sectional drawing of the backflow prevention valve which concerns on Example 2 of this invention. It is sectional drawing of the backflow prevention valve which concerns on Example 3 of this invention. It is sectional drawing of the backflow prevention valve which concerns on Example 4 of this invention. It is sectional drawing of the backflow prevention valve which concerns on Example 5 of this invention. It is sectional drawing of the backflow prevention valve which concerns on Example 6 of this invention. It is sectional drawing of the backflow prevention valve which concerns on Example 7 of this invention.

  A float type check valve (hereinafter referred to as a check valve) according to an embodiment of the present invention will be described with reference to the drawings. The configuration of the present invention is not limited to the embodiment.

  FIG. 1 is a cross-sectional view of a check valve 1 according to Embodiment 1 of the present invention. FIG. 2 is a view of the state where the annular valve seat 6 and the valve seat retainer 14 are attached to the main body 5 of the check valve 1 as viewed from the downstream side, and FIG. 3 is a plan view of the bottom plate 8 of the check valve 1. is there.

  As shown in FIG. 1, the backflow prevention valve 1 of this embodiment is disposed in a drainage system that discharges wastewater generated on a floor surface 2 of a building to a river or the sea. To prevent backflow. The drainage system includes a recess H formed on the floor surface 2, a drain pipe 3 extending downward from the bottom surface of the recess H, and the like. The backflow prevention valve 1 is disposed at the upper end of the drain pipe 3.

  The check valve 1 includes a main body 5, an annular valve seat 6 attached to the main body 5 and four guide rods 7, a bottom plate 8 attached to the guide rod 7, an annular valve seat 6, a guide rod 7 and a bottom plate 8. Two floats 9A, 9B, etc. disposed inward are provided. The main body 5 has an annular (perforated disk) shape with a stepped inner surface having an upstream port 11 having a circular cross section penetrating in the vertical direction. A fixture 10 is screwed to the outer periphery of the upper portion of the main body 5. The fixture 10 is fixedly supported on the floor 2 by welding 4.

  The annular valve seat 6 is made of rubber, for example, and has a communication opening 6A in the center. The annular valve seat 6 is pressed and fixed to the lower end of the main body 5 via a valve seat retainer 14 (see FIG. 2). The annular valve seat 6 communicates the upstream upstream port 11 and the downstream drainage pipe 3 via the communication opening 6A.

  As shown in FIG. 2, the valve seat retainer 14 has an annular structure. The valve seat retainer 14 has a small screw hole 12 for inserting a small screw 13 (see FIG. 1) for fixing the annular valve seat 6 and a screw hole 15 for inserting the guide rod 7. The valve seat retainer 14 is fixed to the main body 5 with a machine screw 13 as shown in FIG.

  The four guide rods 7 are made of metal such as stainless steel, and the upper ends thereof are screw-coupled to the screw holes 15 provided at equal intervals on the lower end of the main body 5, and are fixedly supported by the main body 5. The four guide rods 7 guide the floats 9A and 9B in the vertical direction. It should be noted that at least three guide rods 7 need only be provided.

  Further, the lower end portion of the guide bar 7 is screwed into the nut 17 while passing through the guide bar hole 16 (see FIG. 3) of the bottom plate 8. The bottom plate 8 is supported by the nut 17 so that the plate surface is horizontal, and is positioned below the float 9B to define the lower limit position of the movement of the floats 9A and 9B. It should be noted that the plate surface of the bottom plate 8 does not need to be precisely horizontally supported and may be substantially horizontal. Moreover, the baseplate 8 has the some through-hole 18 for allowing drainage to pass through, as shown in FIG. The float 9A corresponds to the first float of the present invention, and the float 9B corresponds to the second float of the present invention.

  The floats 9A and 9B are made of a metal such as stainless steel and have the same hollow spherical shape as shown in FIG. The floats 9 </ b> A and 9 </ b> B are formed with a lighter specific gravity than the drainage, and move up and down (floating and descending) between the annular valve seat 6 and the bottom plate 8 as the water level in the drainage pipe 3 changes. In the lowered state, the floats 9A and 9B are stacked on the bottom plate 8 as shown in FIG. The float 9A opens and closes the annular valve seat 6 by rising and lowering. The float 9B comes into contact with the float 9A when ascending and moves the float 9A upward (pushes up). That is, the float 9B applies an upward force (contact force) to the float 9A when ascending.

  In normal times, the water level in the drain pipe 3 is generally lower than the position where the bottom plate 8 is disposed. Therefore, the floats 9A and 9B are lowered by their own weight and stacked on the bottom plate 8 as shown in FIG. In this state, the annular valve seat 6 is opened. As a result, the drainage flows from the floor surface 2 (upstream) to the upstream port 11, the communication opening 6 </ b> A of the annular valve seat 6, between the guide rods 7 and through the through hole 18 to the downstream port 19, and finally the river or the like (downstream) ).

  On the other hand, at the time of backflow of water from the downstream side, the water level in the drain pipe 3 rises from the downstream side toward the annular valve seat 6, so that, for example, the float 9B is completely submerged and further the lower part of the float 9A is substantially omitted. Each of the floats 9A and 9B starts to float with half of them submerged. In the case of a single body, the float 9B starts to float in a state where the lower half of the float 9B is submerged. However, the float 9B starts to float as described above due to the weight of the float 9A. As the water level further rises, the floats 9A and 9B also rise, and finally the float 9A closes the annular valve seat 6. The float 9B remains in contact with the float 9A even while the float 9A closes the annular valve seat 6.

  Therefore, in addition to the buoyancy of the float 9A, the upward contact force from the float 9B acts, so that the closing force of the annular valve seat 6 increases. Thereby, it is possible to reliably prevent water from flowing back upstream from the annular valve seat 6 and overflowing to the floor surface 2 and the like. The floats 9A and 9B do not have to have a precise spherical shape, but may have a substantially spherical shape to the extent that the annular valve seat 6 can be closed.

  Here, the contact force applied from the float 9B to the float 9A includes not only the buoyancy of the float 9B but also the drag received by the float 9B from the backflow water. At the time of reverse flow, the reverse flow water flows from the downstream side of the drain pipe in the direction of the annular valve seat 6 (upward direction), and thus the drag from the reverse flow water acts on the floats 9A and 9B. As a result, the floats 9A and 9B are urged upward. Since the drag is proportional to the area, the total drag received by the plurality of floats 9A and 9B is larger than the drag received by the single float.

  As described above, by using the plurality of floats 9A and 9B, the closing force of the annular valve seat 6 is increased as compared with the configuration using a single float. Moreover, it is not necessary to enlarge the first float (float 9A) for closing the annular valve seat 6. Further, the first float has a spherical shape that can be easily fitted into the annular valve seat in any direction. Therefore, it is possible to increase the closing force of the annular valve seat by the first float while suppressing the flow of the drainage.

  The second float (float 9B) in this embodiment has the same shape as the first float (float 9A), but is not particularly limited thereto. For example, a spherical float smaller than the first float may be used.

  In this embodiment, a single float 9B is used as the second float, but the present invention is not particularly limited to this. For example, a plurality of floats having the same shape or a plurality of floats having different shapes may be used as the second float.

  Further, in this embodiment, the float 9B is submerged and the floats 9A and 9B begin to float while the bottom half of the float 9A is submerged. However, the timing at which the float 9A begins to float is particularly limited to this. is not. Any configuration may be used as long as the floats 9A and 9B float and the float 9A can close the annular valve seat 6.

  This embodiment is different from Example 1 described above in the configuration of the float. This different configuration will be described with reference to FIG. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  FIG. 4 is a cross-sectional view of the check valve 100 according to Embodiment 2 of the present invention. In this embodiment, a float 9A similar to the first embodiment and a float 90B different from the first embodiment are used. The float 90B has a hollow bottomed cylindrical shape, and an upper end portion and a lower end portion have a hemispherical shape.

  Thus, even when the second float (float 90B) having a shape different from that of the first float (float 9A) is used, the same effects as those of the first embodiment can be obtained.

  This embodiment is different from the above-described first embodiment in the configuration of the float. This different configuration will be described with reference to FIG. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  FIG. 5 is a cross-sectional view of the backflow prevention valve 101 according to Embodiment 3 of the present invention. In this embodiment, a float 9A similar to the first embodiment and a float 91B different from the first embodiment are used. The float 91B has a hollow bottomed cylindrical shape, and an upper end portion and a lower end portion have a disk shape.

  Thus, even when the second float (float 91B) having a shape different from that of the first float (float 9A) is used, the same effects as those of the first embodiment can be obtained. Note that either the upper end portion or the lower end portion of the float 91B may have a hemispherical shape like the float 90B shown in the second embodiment.

  This embodiment is different from the above-described first embodiment in the configuration of the float. This different configuration will be described with reference to FIG. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  FIG. 6 is a cross-sectional view of the backflow prevention valve 102 according to Embodiment 4 of the present invention. In this embodiment, a float 9A similar to the first embodiment and two floats 92B and 92C different from the first embodiment are used. The floats 92B and 92C have the same hollow sphere shape, and in a lowered state, the floats 92B and 92C are aligned horizontally on the bottom plate 8 as shown in FIG. Then, the float 9A is placed on the floats 92B and 92C. The floats 92B and 92C correspond to the second float of the present invention, and apply an upward force (contact force) to the float 9A when ascending.

  Thus, even if it is the structure which has arrange | positioned the 2nd float (float 92B, 92C) in the horizontal direction, there can exist an effect similar to the above-mentioned Example 1. FIG. In this embodiment, the floats 92B and 92C having the same shape are used, but different shapes may be used. Further, the number of second floats arranged in the horizontal direction is not limited to two as long as it is located below the first float. Furthermore, the structure which arrange | positioned another 2nd float below float 92B, 92C may be sufficient.

  This embodiment differs from the first embodiment described above in the configuration in which the backflow prevention valve is provided between the two drain pipes. This different configuration will be described with reference to FIG. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  FIG. 7 is a cross-sectional view of the backflow prevention valve 103 according to Embodiment 5 of the present invention. The main body 50 of the backflow prevention valve 103 has a male screw 51a on a part of the outer periphery. The male screw 51 a is screwed to the female screw 30 a formed on a part of the inner periphery of the drain pipe 30, so that the backflow prevention valve 103 is attached to the drain pipe 30. In addition, an upstream drain pipe (not shown) is connected to the upper end of the main body 50 by screw coupling in the same manner as the drain pipe 30.

  This embodiment differs from the first embodiment described above in the configuration in which the backflow prevention valve is provided between the two drain pipes. Moreover, the structure provided between two drain pipes using a fixture is different from the above-described fifth embodiment. This different configuration will be described with reference to FIG. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  FIG. 8 is a cross-sectional view of the check valve 104 according to Embodiment 6 of the present invention. As for the main body 51 of the backflow prevention valve 104, the outer periphery of the upper end protruding from the drain pipe 31 is screwed to the fixture 400. The fixture 400 has a substantially cylindrical shape, and a female screw 400 a provided on the inner periphery is screwed to a male screw 31 a provided on the outer periphery of the end of the drain pipe 31. As a result, the backflow prevention valve 104 is attached to the drain pipe 31 via the fixture 400. Further, an upstream drain pipe (not shown) is screwed to the upper end of the fixture 400 so as to be fitted on the fixture 400.

  This embodiment differs from the first embodiment described above in the configuration in which the backflow prevention valve is provided between the two drain pipes. Further, the configuration provided between two drain pipes using a flange is different from the above-described fifth and sixth embodiments. This different configuration will be described with reference to FIG. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  FIG. 9 is a cross-sectional view of the backflow prevention valve 105 according to Embodiment 7 of the present invention. The main body 52 of the backflow prevention valve 105 has a flange 52b at the upper end. The flange 52 b is fixed to the flange 32 b provided on the outer periphery of the end portion of the drain pipe 32 by the bolt 450, so that the backflow prevention valve 105 is attached to the drain pipe 32. An upstream drain pipe (not shown) is fixed to the flange 52 b at the upper end of the main body 52 in the same manner as the drain pipe 32.

[Other Examples]
The plurality of floats and the bottom plate of the above-described embodiment are preferably made of metal in order to prevent mutual sticking. This is because the reverse flow itself does not occur frequently, and therefore, the plurality of floats are basically placed on the bottom plate, and when formed with resin or the like, they are easily fixed to the bottom plate.

  In the above-described embodiment, the bottom plate is used as the defining member for defining the lower limit position of the float. However, the bottom plate is not particularly limited as long as the lower limit position can be defined. For example, it may be a saddle-shaped defining member having a recess where the float lands.

  This invention discharges wastewater generated in the grounds and buildings of factories to rivers, seas, public drainage facilities, etc., and drains water used in public baths, etc. It can be used in the industrial field where construction, sales and operation of drainage drainage systems are performed.

DESCRIPTION OF SYMBOLS 1,100-105 Float type backflow prevention valve 5, 50, 51, 52 Main body 6 Annular valve seat 7 Guide rod (guide member)
8 Bottom plate (regulating member)
9A float (first float)
9B, 90B, 91B, 92B, 92C Float (second float)

Claims (3)

A float type backflow prevention valve disposed in a drainage system that drains from upstream to downstream,
An annular valve seat that opens in the vertical direction and communicates the upstream side and the downstream side of the drainage system;
A plurality of floats arranged to be vertically movable on the downstream side below the annular valve seat and arranged side by side in the vertical direction;
A guide member for guiding the vertical movement of the plurality of floats;
A defining member that defines a lower limit position of movement of the plurality of floats;
With
The plurality of floats are:
As the water level rises, the annular valve seat is closed by fitting into the opening and closing the opening, and by lowering the water level of the drainage to release the opening. A spherical first float for opening the annular valve seat;
A second float that is located below the first float and floats and descends as the water level of the drainage changes;
Float type check valve including   The float type check valve according to claim 1, wherein the second float has the same spherical shape as the first float.   2. The float according to claim 1, wherein the second float has an outer diameter that is the same as the outer diameter of the first float, and has a cylindrical shape with an upper end facing the first float and a lower end facing the defining member. Type check valve.

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