JP6914072B2 - Ball valve - Google Patents

Description

The present invention relates to a ball valve used in a fluid transport piping line in various industries such as a chemical factory, water and sewage, agriculture, fishery industry, semiconductor manufacturing field, and food field.

A ball valve is a valve that can be opened and closed by rotating about 90 degrees, has a simple structure, and is economical. However, since the flow rate changes rapidly according to the opening, there are two open states, a fully open state and a fully closed state. Often used in degrees.

As a ball valve whose flow rate can be adjusted by changing the opening degree, for example, there is a ball valve described in Patent Document 1. The configuration is a volume control insert with a horizontally elongated or parabolic elongated slot for adjusting the flow rate at the position where the fluid passage of the ball valve or the valve seat of the valve housing is attached to give a predetermined flow rate condition. It was a thing.

In addition, when the ball valve is fully closed, fluid stays inside the piping on the upstream side of the ball valve and inside the ball valve, making it easier for germs to grow, and the piping and ball valve due to the accumulation and expansion of the fluid due to freezing. May be damaged. In order to prevent fluid from staying inside the piping and ball valve, the opening of the ball valve may be set to a small opening and the fluid may flow slightly, but it is difficult to set the opening and an external force is suddenly applied to the handle. If it is applied, the opening may change.

As a ball valve capable of stably adjusting the flow rate to a minute flow rate, for example, there is a ball valve described in Patent Document 2. The configuration was such that a sub-flow passage having a diameter smaller than that of the main flow passage was formed at a position orthogonal to the main flow passage formed in the ball of the ball valve.

Japanese Unexamined Patent Publication No. 11-270711 Japanese Unexamined Patent Publication No. 2005-98425

However, in the valve according to Patent Document 1, when the volume control insert is attached to the valve housing, the surface of the volume control insert on the ball valve side is in full contact with the ball valve. Therefore, each time the ball valve is opened and closed, the volume control insert and the ball valve slide, the volume control insert or the ball valve is scraped, and foreign matter is generated. Further, when the volume control insert or the ball valve is worn, foreign matter may be accumulated in the gap created by the wear or the fluid may stay and germs may propagate. Further, in the valve according to Patent Document 2, a small-diameter sub-flow passage is formed in a thick ball. In order to form the sub-flow passage, it is necessary to make the thickness of the drill so that it does not break when the sub-flow passage is cut, and a flow rate larger than the desired flow rate may flow. In particular, when the fluid is expensive, the cost of the fluid to be flowed to prevent the fluid from staying inside the pipe or the ball valve becomes large.

An object of the present invention is to provide a ball valve capable of reducing the flow rate when flowing a fluid for the purpose of solving the above-mentioned problems of the prior art and preventing the generation of foreign matter and the retention of the fluid inside the ball valve. It is to be.

According to the first aspect of the present invention, a valve body including a first flow path, a second flow path, and a valve chamber communicating the first flow path and the second flow path, and a first flow path side in the valve chamber. A sheet located in the valve chamber, a flow rate adjusting sheet located on the second flow path side in the valve chamber and configured to adjust the flow rate of the fluid flowing through the first flow path and the second flow path, and a sheet and a flow rate adjusting sheet. In a ball valve provided with a ball valve body rotatably arranged between them, having a through hole serving as a valve body flow path, and communicating or blocking the first flow path and the second flow path, the flow rate adjusting sheet is provided. The seat portion is provided with an annular seat portion and a flow rate adjusting portion located on the inner peripheral side of the seat portion. The seat portion is provided with a sealing surface on which the ball valve body slides and seals the fluid. It is provided with a flow rate adjusting opening that communicates the second flow path and the valve chamber, and a guide surface that is continuously connected to the seal surface and is configured to separate from the ball valve body and guide the fluid. the gap between the face and the ball valve body, Ri Na continuously increases toward the outer circumferential edge of the guide surface in the flow path axis, the sealing surface is the same radius of the spherical surface and the radius of the ball valve body guiding face the ball A ball valve is provided, which is a spherical surface with a radius smaller than the radius of the valve body.

That is, in the first aspect of the present invention, the guide surface of the flow rate adjusting sheet is continuously connected to the sealing surface and separated from the ball valve body. Further, the gap between the guide surface and the ball valve body continuously increases as it approaches the flow path axis from the outer peripheral edge of the guide surface. According to this aspect, when the ball valve body rotates, the ball valve body and the flow rate adjusting portion can be made non-contact, so that the ball valve body does not come into contact with the flow rate adjusting portion and slide, and the flow rate adjusting sheet It is possible to reduce the generation of foreign matter due to wear and sliding. Further, since the fluid flowing through the valve body flow path easily flows from the outer peripheral edge of the guiding surface toward the center along the guiding surface, a retention portion is less likely to occur in the gap between the guiding surface and the ball valve body, and the gap is created. It can be effectively flushed, and foreign matter can be prevented from accumulating in the gaps and germs can be prevented from being generated. In addition, since the guide surface becomes a spherical surface that swells toward the second flow path, the fluid flowing through the valve body flow path becomes easier to flow along the outer peripheral edge of the guide surface, and the outer peripheral edge of the guide surface is flushed more effectively. can.

According to a second aspect of the present invention, Oite the first state-like, sheet portion has a communication groove for communicating the first passage and the valve chamber, the ball valve body is perpendicular to the valve body flow passage A ball valve is provided which has an auxiliary flow path having an inner diameter smaller than that of the valve body flow path, and the auxiliary flow path communicates between the valve body flow path and the second flow path at least when the valve body flow path is fully closed. ..

That is, when the ball valve is in the fully closed state, the first flow path, the valve chamber, the valve body flow path, and the second flow path communicate with each other, so that the fluid can flow into the ball valve little by little even in the fully closed state. , Fluid retention in the valve chamber and valve body flow path can be suppressed, and generation of germs, accumulation of foreign matter, sticking, etc. can be reduced.

According to the third aspect of the present invention , in the second aspect, the auxiliary flow path communicates with the large-diameter flow path located on the outer peripheral side of the ball valve body, and the large-diameter flow path and the valve body flow path are large. A ball valve is provided that has a small diameter flow path having an inner diameter smaller than that of the diameter flow path, and the length of the small diameter flow path is shorter than that of the large diameter flow path.

That is, the auxiliary flow path is formed stepwise by a large-diameter flow path and a small-diameter flow path shorter than the large-diameter flow path. According to this aspect, the drill used for drilling the small-diameter flow path is less likely to break, and the outer diameter of the drill can be reduced, so that the inner diameter of the small-diameter flow path can be reduced and the flow rate for preventing retention in the ball valve can be reduced. can.

According to the fourth aspect of the present invention , in the third aspect, a ball valve having an inner diameter of 0.1 mm or more and less than 1 mm of a small diameter flow path is provided.

According to this aspect, since the drill used for drilling the small-diameter flow path is hard to break, it is possible to stably drill even the small-diameter flow path having an inner diameter of less than 1 mm. Further, since the inner diameter of the small-diameter flow path is 0.1 mm or more, a fluid such as pure water can be stably flowed through the small-diameter flow path.

According to the present invention, by reducing the contact area between the flow rate adjusting sheet and the ball valve body and increasing the gap between the flow rate adjusting sheet and the ball valve body as it approaches the flow path axis, foreign matter may be generated. It is possible to provide a ball valve that can prevent fluid from staying in the gap. Further, a communication groove for communicating the first flow path and the valve chamber is formed in the seat, and an auxiliary flow path for communicating the valve body flow path and the second flow path in the ball valve body is relatively large-diameter hole and relatively. It is possible to provide a ball valve that can prevent the fluid from staying in the ball valve with a small flow rate by forming the holes in a small diameter stepwise.

It is sectional drawing which shows the fully opened state of the ball valve which concerns on 1st Embodiment of this invention. It is a drawing which shows the flow rate adjustment sheet used for the ball valve which concerns on 1st Embodiment of this invention, (a) is a perspective view, (b) is a perspective view from another angle, (c). ) Is a cross-sectional view. It is the main part enlarged AA sectional view which shows each opening state of the ball valve which concerns on 1st Embodiment of this invention, (a) is the drawing which shows the fully closed state, (b) is a half-open state. It is a drawing which shows, and (c) is a drawing which shows the fully open state. It is a side view from the 2nd flow path side of the ball valve which concerns on 1st Embodiment of this invention. It is an enlarged sectional view of the main part which shows the fully closed state of the ball valve which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows the method of drilling an auxiliary flow path in the ball valve body used for the ball valve which concerns on 2nd Embodiment of this invention, and (a) is the drawing which shows the state which drilled the large-diameter flow path. , (B) are drawings showing a state in which a small-diameter flow path is perforated.

(First Embodiment)
Hereinafter, the first embodiment of the present invention will be described with reference to the drawings, but it goes without saying that the present invention is not limited to the present embodiment.

FIG. 1 is a cross-sectional view showing a fully opened state of the ball valve according to the first embodiment, FIG. 2 is a drawing showing a flow rate adjusting sheet used for the ball valve according to the first embodiment, and FIG. 3 is a drawing showing a flow rate adjusting sheet. FIG. 4 is an enlarged cross-sectional view taken along the line AA showing each opening state of the ball valve according to the first embodiment, and FIG. 4 is a side view from the second flow path side of the ball valve according to the first embodiment. ..

As shown in FIGS. 1 to 4, the ball valve is the first flow rate of the valve body 1 so as to be in constant contact with the valve body 1, the ball valve body 2 arranged inside the valve body 1, and the ball valve body 2. The flow rate of the fluid located on the second flow path 12 side of the valve body 1 and flowing through the first flow path 11 and the second flow path 12 so as to be in constant contact with the seat 3 located on the road 11 side and the ball valve body 2. It has a flow rate adjusting sheet 4 configured to be adjusted. The ball valve body 2 is connected to the handle 6 which is an operation unit via the stem 5. The ball valve body 2 rotates following the rotation of the handle 6 to communicate or shut off the first flow path 11 and the second flow path 12 of the valve body 1.

The valve body 1 is made of polyvinyl chloride (hereinafter referred to as PVC) and has a diameter of 25 mm. The valve body 1 has a substantially hollow cylindrical shape, and inside, the first flow path 11, the second flow path 12 having the same flow path axis as the first flow path 11, and the first flow path 11 and the second flow path 12 It has a valve chamber 13 that communicates with the valve chamber 13. An annular recess 14 centered on the flow path axis is formed on the wall surface of the valve chamber 13 on the second flow path 12 side, and the flow rate adjusting sheet 4 is fitted into the recess 14. An annular groove 10 is formed on the bottom surface of the recess 14, and the first cushion 16 is fitted and inserted into the annular groove 10. A notch groove 15 is formed on the outer peripheral edge of the recess 14 so as to project toward the outer peripheral side of the recess 14 in the radial direction. A through hole into which the stem 5 is inserted is formed so as to communicate with the valve chamber 13 in the direction intersecting the flow path axis of the valve body 1. Male threaded portions are formed on the outer peripheral surfaces of both ends of the valve body 1, and female threaded portions are formed on the inner peripheral surface of the end portion on the first flow path 11 side.

The ball valve body 2 is made of PVC and has a spherical shape. An engaging groove having a trapezoidal cross section with which the stem 5 is engaged is formed on the upper surface of the ball valve body 2. Inside the ball valve body 2, a through hole having a circular cross section is formed to serve as a valve body flow path 21.

The stem 5 is made of PVC and has a substantially cylindrical shape. An engaging portion that is engaged with the engaging groove of the handle 6 is formed at the upper end portion of the stem 5, and a cross-sectional trapezoidal shape that is engaged with the engaging groove of the ball valve body 2 is formed at the lower end portion of the stem 5. An engaging portion is formed, and an annular groove into which an O-ring is fitted is formed on the outer peripheral surface of the stem 5. The handle 6 is made of an acrylonitrile-butadiene-styrene copolymer synthetic resin (hereinafter referred to as ABS), and an engaging groove to be engaged with the engaging portion of the stem 5 is formed in the central portion of the lower surface. When the handle 6 is rotated around the axis of the stem 5, the ball valve body 2 connected to the handle 6 via the stem 5 rotates following the rotation of the handle 6. By rotating the ball valve body 2, the valve body flow path 21, the first flow path 11 and the second flow path 12 are communicated with or cut off.

The valve body retainer 9 is made of PVC and has a cylindrical shape. A seat 3 and a second cushion 17 are fitted to the end surface of the valve body retainer 9 on the ball valve body 2 side, and an O-ring is arranged on the other end surface of the valve body retainer 9. Further, an O-ring is arranged on the outer peripheral surface of one end of the valve body retainer 9, and a male screw portion screwed to the female screw portion of the valve body is provided on the outer peripheral surface of the other end of the valve body retainer 9. It is formed. By screwing the valve body retainer 9 to the valve body 1, the ball valve body 2 is pressed toward the second flow path 12. At this time, the ball valve body 2 is pressed against the flow rate adjusting sheet 4 and the sheet 3 from both flow path directions in the valve chamber 13 via the first cushion 16 and the second cushion 17, respectively.

Sheet 3 is made of polytetrafluoroethylene (hereinafter referred to as PTFE) and has an annular disk shape. The seat 3 is arranged in the valve chamber 13, and the center of the seat 3 is located on the flow path axis. The seat 3 is provided with a sealing surface 31 on which the ball valve body 2 slides and seals the fluid, and the sealing surface 31 is formed by an inclined surface which is a conical surface. By making the seal surface 31 a conical surface, the contact between the ball valve body 2 and the seal surface 31 can be made into line contact, and the operation torque for rotating the ball valve body 2 can be reduced.

The flow rate adjusting sheet 4 is made of PTFE and has an annular disk shape. The flow rate adjusting sheet 4 is arranged in the valve chamber 13, and the center of the flow rate adjusting sheet 4 is located on the flow path axis. The flow rate adjusting sheet 4 has an annular seat portion 42 fitted into an annular recess 14 arranged in the valve chamber 13 and a flow rate adjusting portion 44 located on the inner peripheral side of the seat portion 42. .. On the outer peripheral edge of the flow rate adjusting sheet 4, a protrusion 41 that is fitted and inserted into the notch groove 15 formed in the recess 14 of the valve chamber 13 is formed. The protrusion 41 prevents the flow rate adjusting sheet 4 from rotating when the flow rate adjusting sheet 4 is fitted into the valve body 1.

Similar to the seat 3, the seat portion 42 includes a sealing surface 43 on which the ball valve body 2 slides and seals the fluid. The sealing surface 43 is formed so as to be a spherical surface having a radius substantially the same as the radius R1 of the ball valve body 2. When the sealing surface 43 is made spherical instead of conical in this way, the contact between the ball valve body 2 and the sealing surface 43 becomes surface contact. The ball valve according to the present embodiment is a ball valve having a flow rate adjusting function and is often used in the half-open state. Therefore, when the ball valve is in the half-open state, the ball valve body 2 is pressed against the seal surface 43 to seal. It is possible to reduce scratches on the surface 43 and biting of the ball valve body 2. Here, if the outer shape such as the thickness of the sheet 3 is substantially the same as the shape of the sheet portion 42, the sheet 3 can be fitted and inserted into the recess 14 in the same manner as the flow rate adjusting sheet 4, so that it is a standard without a flow rate adjusting function. At the time of specification, it is preferable that the sheet 3 can be fitted into the recess 14 instead of the flow rate adjusting sheet 4.

On the second flow path 12 side of the flow rate adjusting unit 44, a cylindrical protrusion 45 having a diameter slightly smaller than that of the second flow path 12 is formed. Since the protruding portion 45 is fitted in the second flow path 12, the wall thickness of the flow rate adjusting portion 44 can be increased while suppressing the change in the total length of the ball valve, and the strength of the flow rate adjusting sheet 4 can be secured. Further, the flow rate adjusting unit 44 is formed with a flow rate adjusting opening 46 that communicates with the second flow path 12 and the valve chamber 13 to adjust the flow rate of the ball valve. The flow rate adjusting opening 46 is generally fan-shaped, and extends from one of the axes orthogonal to the rotation center axis of the ball valve body 2 to the other. That is, the area of the opening S (see FIG. 4) formed by the flow rate adjusting opening 46 and the through hole of the ball valve body 2 increases as the ball valve changes from the fully closed state to the fully open state. By forming the flow rate adjusting opening 46 not in the ball valve body 2 but in the flow rate adjusting sheet 4, it is easier to process and the volume of parts stock is increased as compared with the case where the flow rate adjusting opening 46 is formed in the ball valve body 2. Can be reduced. In particular, when the flow rate adjusting sheet 4 is formed of PTFE, one kind of material can be applied to many usage conditions, so that the number of parts inventories can be reduced.

The flow rate adjusting unit 44 is continuously connected to the seal surface 43 to form an induction surface 47 for guiding the fluid to the second flow path 12. The guide surface 47 is formed on a spherical surface having a radius R2 smaller than the radius R1 of the ball valve body 2 and is separated from the ball valve body 2. Here, in FIG. 2C, the radius R2 of the guide surface 47 is made easy to understand by a virtual line. The guide surface 47 is formed so as to approach the surface of the flow rate adjusting sheet 4 on the second flow path 12 side as it approaches the flow path axis. That is, the gap 25 between the guide surface 47 and the ball valve body 2 becomes larger as it approaches the flow path axis.

The cap nut 7 is made of PVC and has a substantially cylindrical shape. On the inner peripheral surface of one end of the cap nut 7, female screw portions screwed to the male screw portions formed at both ends of the valve body 1 are formed, and the other end of the cap nut 7 has a female screw portion. , An inner flange portion protruding toward the inner diameter side is formed. The short tube 8 with a flange is made of PVC, and an outer flange portion projecting to the outer diameter side is formed at one end thereof. The flanged short pipe 8 is sandwiched and fixed to both end faces of the valve body 1 by cap nuts 7.

Next, the operation of the ball valve of the first embodiment will be described with reference to FIGS. 1 to 4. When the handle 6 of the ball valve is rotated, the stem 5 rotates following the handle 6, and the ball valve body 2 further rotates following the handle 6. The ball valve body 2 rotates within a range of 90 degrees. When the ball valve body 2 is rotated from the fully closed state (FIG. 3a), it becomes a half-open state (FIG. 3b), and the first flow path 11 and the second flow path 12 communicate with each other by the valve body flow path 21. The fluid flowing through the valve body flow path 21 flows from the outer peripheral edge of the guide surface 47 along the guide surface 47 and flows into the flow rate adjusting opening 46. Further, when the ball valve body 2 is rotated, it is in a fully opened state (FIG. 3c). The opening S (see FIG. 4) formed by the valve body flow path 21 and the flow rate adjusting opening 46 changes according to the rotation of the ball valve body 2, and the opening S increases as the amount of rotation of the ball valve body 2 increases. The area of is also large.

The guide surface 47 of the flow rate adjusting sheet 4 is formed on a spherical surface having a radius R2 smaller than the radius R1 of the ball valve body 2 and is separated from the ball valve body 2. Therefore, even if the ball valve body 2 rotates, the ball valve body 2 and the flow rate adjusting unit 44 do not come into contact with each other, and foreign matter is generated due to wear or sliding of the flow rate adjusting sheet 4 due to the rotation of the ball valve body 2. Can be reduced. Further, since the ball valve body 2 and the flow rate adjusting unit 44 are separated from each other, even if the flow rate adjusting unit 44 is provided, the operating torque can be the same as that of a general ball valve not provided with the flow rate adjusting unit 44. Further, the guide surface 47 is formed so that the gap 25 between the guide surface 47 and the ball valve body 2 becomes larger as it approaches the flow path axis. Further, the guide surface 47 is continuously connected to the seal surface 43. Therefore, the fluid flowing through the valve body flow path 21 tends to flow from the outer peripheral edge of the guiding surface 47 toward the center along the guiding surface 47, so that a retention portion is formed in the gap 25 (particularly near the outer peripheral edge of the guiding surface 47). It is less likely to occur. In the ball valve, foreign matter is likely to accumulate in the gap 25 in the fully closed state or the gap 25 far from the valve body flow path 21 in the half-open state, or fluid is likely to stay and germs are likely to be generated, but the ball valve is fully open. By putting it in a state, the entire gap 25 can be flushed and effectively cleaned.

In the first embodiment, the flow rate adjusting opening 46 is formed in a substantially fan shape, but the shape of the flow rate adjusting opening 46 can be appropriately selected depending on what kind of flow rate adjustment is performed, and other shapes such as a rectangle and an anchor Examples include shape and right-angled trapezoid. Further, the opening for forming the flow rate adjusting opening 46 is not limited to one, and the flow rate adjusting opening 46 may be formed with a plurality of holes.

In the first embodiment, the sealing surface 31 of the seat 3 is formed by an inclined surface which is a conical surface, but is substantially the same as the radius R1 of the ball valve body 2 like the sealing surface 43 of the flow rate adjusting sheet 4. It may be formed so as to be a spherical surface having a radius. Further, the sealing surface 43 of the flow rate adjusting sheet 4 is formed so as to be a spherical surface having substantially the same radius as the radius R1 of the ball valve body 2, but it is a conical surface like the sealing surface 31 of the sheet 3. It may be formed on an inclined surface.

In the first embodiment, the guide surface 47 is formed to be a spherical surface having a radius R2 smaller than the radius R1 of the ball valve body 2, but the gap 25 between the guide surface 47 and the ball valve body 2 is a flow path. It should increase as it approaches the axis. Other shapes include a conical surface, a pyramid surface, an elliptical surface, and a combination of a plurality of curved surfaces and tapered surfaces. Suitable. By doing so, the fluid flowing through the valve body flow path 21 becomes easier to flow along the outer peripheral edge of the guiding surface 47, and the outer peripheral edge of the guiding surface 47 can be flushed more effectively.

Next, the ball valve of the second embodiment according to the present invention will be described with reference to FIGS. 5 to 6. FIG. 5 is an enlarged cross-sectional view of a main part showing a fully closed state of the ball valve according to the second embodiment, and FIG. 6 shows an auxiliary flow path in the ball valve body used for the ball valve according to the second embodiment. It is sectional drawing which shows the method of drilling. The second embodiment differs from the first embodiment mainly in that the auxiliary flow path 22 for preventing the fluid from staying inside the ball valve is formed. In FIGS. 5 to 6, the components having the same functions and functions as those in the first embodiment are designated by the same reference numerals as those in FIGS. 1 to 4, and the differences from the first embodiment are mainly described below. explain.

In the second embodiment, a communication groove 32 that constantly communicates the first flow path 11 and the valve chamber 13 is formed on the outer peripheral edge of the seat 3. Further, a communication hole is formed as an auxiliary flow path 22 orthogonal to the valve body flow path 21 in the rotation circumferential direction of the ball valve body 2. The auxiliary flow path 22 has a large-diameter flow path 23 having an inner diameter of 4 mm and a small-diameter flow path 24 having an inner diameter of 0.3 mm, which is shorter than the large-diameter flow path 23.

The method of processing the communication hole to be the auxiliary flow path 22 is to first form a bottomed hole to be the large diameter flow path 23 from the outer peripheral surface of the ball valve body 2 toward the valve body flow path 21 with a drill having an outer diameter of 4 mm. .. If the bottom surface of the large-diameter flow path 23 is formed so as to be recessed toward the valve body flow path 21, it is preferable because the drill forming the small-diameter flow path 24 can be easily positioned. Next, a through hole having an outer diameter of 0.3 mm is formed from the center of the bottom surface of the large-diameter flow path 23 toward the valve body flow path 21 to form the small-diameter flow path 24. In the processing method in which the auxiliary flow path 22 is formed stepwise by the large-diameter flow path 23 and the small-diameter flow path 24, the drill used for drilling the small-diameter flow path 24 is easily broken, and the inner diameter of the small-diameter flow path 24 is less than 1 mm. It is suitable at the time of. Further, when a through hole is drilled in the outer peripheral surface of the ball valve body 2 with a thin drill, the drill becomes slippery and easily breaks as the through hole becomes longer. If the length of the small-diameter flow path 24 is shortened, the through hole can be easily machined. In particular, when the inner diameter of the small-diameter flow path 24 is less than 1 mm, the drill is easily broken. Therefore, if the length of the small-diameter flow path 24 is 3 mm or less, the drill is difficult to break and it becomes easy to process. Further, the inner diameter of the small-diameter flow path 24 is preferably 0.1 mm or more so that a fluid such as pure water can stably pass through the small-diameter flow path 24. Since the other structure of the ball valve of the second embodiment is the same as that of the ball valve of the first embodiment, the description thereof will be omitted.

Next, the operation of the ball valve of the second embodiment will be described with reference to FIGS. 5 to 6. When the ball valve is fully closed, the fluid flowing through the first flow path 11 flows into the valve chamber 13 from the communication groove 32 of the seat 3. Then, it flows from the valve chamber 13 into the valve body flow path 21, further passes through the auxiliary flow path 22, and flows into the second flow path 12. In the ball valve of the present embodiment, a small amount of fluid can flow stably even in the fully closed state, so that the retention of the fluid in the valve chamber 13 and the valve body flow path 21 is suppressed, and the generation of germs, the accumulation of foreign substances, and the sticking are suppressed. Can be reduced. At this time, since the auxiliary flow path 22 is formed stepwise by the large-diameter flow path 23 and the small-diameter flow path 24, the inner diameter of the small-diameter flow path 24 can be reduced, and the flow rate for the purpose of preventing retention can be suppressed. Other actions and effects of the ball valve of the first embodiment are the same as those of the ball valve of the first embodiment, and thus the description thereof will be omitted.

In the second embodiment, the auxiliary flow path 22 is formed by a drill, but it may be formed in advance when the ball valve body 2 is formed by injection molding. Also in this case, since the auxiliary flow path 22 includes the large-diameter flow path 23 and the small-diameter flow path 24, the small-diameter flow path 24 is made thinner than when the auxiliary flow path 22 is composed of only the small-diameter flow path 24. It will be easier. Further, only the large-diameter flow path 23 of the auxiliary flow paths 22 may be formed by injection molding. Further, in the second embodiment, the number of communication grooves 32 and the number of auxiliary flow paths 22 are one each, but the number of communication grooves 32 and auxiliary flow paths 22 can be freely designed according to a desired flow rate. can.

In the present invention, the material of the valve body 1, the stem 5, the ball valve body 2, the valve body retainer 9, the seat 3, the flow rate adjusting seat 4, the handle 6, the cap nut 7, and the short tube 8 with a flange is the strength of the valve. A material that satisfies functions such as chemical resistance to fluid can be appropriately selected. For example, resins such as PVC, polypropylene, polyethylene, polyvinylidene fluoride, ABS and PTFE, metals such as stainless steel, iron, copper alloys and aluminum, and ceramics such as porcelain are suitable materials.

Preferred embodiments of the present invention are as described above, but the present invention is not limited thereto. Various other embodiments are made that do not deviate from the gist and scope of the present invention. Furthermore, the actions and effects described in this embodiment are examples and do not limit the present invention.

1 Valve body 2 Ball valve body 3 Seat 4 Flow rate adjustment sheet 5 Stem 6 Handle 7 Cap nut 8 Short pipe with flange 9 Valve body retainer 10 Circular groove 11 1st flow path 12 2nd flow path 13 Valve chamber 14 Recess 15 Notch groove 16 1st cushion 17 2nd cushion 21 Valve body flow path 22 Auxiliary flow path 23 Large diameter flow path 24 Small diameter flow path 25 Gap 31 Seal surface 32 Communication groove 41 Projection 42 Seat part 43 Seal surface 44 Flow rate adjustment part 45 Protrusion part 46 Flow rate Adjustable opening 47 Guide surface

Claims (4)

A valve body including a first flow path, a second flow path, and a valve chamber that communicates the first flow path and the second flow path.
A sheet located on the first flow path side in the valve chamber,
A flow rate adjusting sheet located on the second flow path side in the valve chamber and configured to adjust the flow rates of the first flow path and the fluid flowing through the second flow path.
A ball valve body that is rotatably arranged between the sheet and the flow rate adjusting sheet, has a through hole that serves as a valve body flow path, and communicates or shuts off the first flow path and the second flow path. In a ball valve equipped with,
The flow rate adjusting sheet includes an annular seat portion and a flow rate adjusting portion located on the inner peripheral side of the seat portion.
The seat portion includes a sealing surface on which the ball valve body slides and seals the fluid.
The flow rate adjusting unit is continuously connected to the sealing surface and separated from the ball valve body and guides the fluid with the flow rate adjusting opening that communicates the second flow path and the valve chamber. With a guide surface, which is composed,
Clearance between the ball valve member and the guide surface is Ri Na continuously increases toward the passage axis from the outer peripheral edge of the guide surface,
The sealing surface is a spherical surface having the same radius as the radius of the ball valve body.
A ball valve characterized in that the guide surface is a spherical surface having a radius smaller than the radius of the ball valve body . The seat portion has a communication groove that communicates the first flow path and the valve chamber.
The ball valve body is orthogonal to the valve body flow path and has an auxiliary flow path having an inner diameter smaller than that of the valve body flow path. When the ball valve body is at least fully closed, the auxiliary flow path is the valve body flow path. The ball valve according to claim 1 , wherein the ball valve communicates with the second flow path. The auxiliary flow path communicates with a large-diameter flow path located on the outer peripheral side of the ball valve body, the large-diameter flow path and the valve body flow path, and a small-diameter flow path having an inner diameter smaller than that of the large-diameter flow path. Have,
The ball valve according to claim 2 , wherein the length of the small-diameter flow path is shorter than that of the large-diameter flow path. The ball valve according to claim 3 , wherein the inner diameter of the small-diameter flow path is 0.1 mm or more and less than 1 mm.

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