JP2018165540A - Ball valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball valve capable of reducing a flow rate of a fluid flowing to prevent generation of foreign matters inside of the ball valve and stagnation of the fluid.SOLUTION: In a ball valve including a flow rate adjustment seat 4 positioned at a second flow channel 12 side in a valve chest 13, and adjusting a flow rate of a fluid flowing in a first flow channel 11 and the second flow channel 12, the flow rate adjustment seat 4 includes an annular seat portion 42 and a flow rate adjustment portion 44 positioned at an inner peripheral side of the seat portion 42, the seat portion 42 includes a seal face 43 for sliding a ball valve element 2 and sealing the fluid, the flow rate adjustment portion 44 includes a flow rate adjustment opening 46 communicating the second flow channel 12 to the valve chest 13, and a guide face 47 continuously connected to the seal face 43, separating from the ball valve element 2, and constituted to guide the fluid. A clearance between the guide face 47 and the ball valve element 2 is continuously increased from an outer peripheral edge of the guide face 47 toward a flow channel axis.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a ball valve used for fluid transportation piping lines in various industries such as chemical factories, water and sewage, agriculture, fisheries industry, semiconductor manufacturing field, and food field.

  A ball valve is normally a valve that can be opened and closed by rotating approximately 90 degrees, and has a simple structure and excellent economy. However, since the flow rate changes abruptly according to the opening, it can be opened in two fully open and fully closed states. 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 such that a volume control insert having an oblong or parabolic elongated slot for adjusting the flow rate is attached at a position where a fluid passage of the ball valve or a valve seat of the valve housing is attached to give a predetermined flow state. It was a thing.

  In addition, when the ball valve is fully closed, the fluid stays in the piping on the upstream side of the ball valve and inside the ball valve, and it becomes easy for bacteria to grow or the fluid is accumulated and expanded due to freezing. May be damaged. In order to prevent fluid from staying inside the piping or ball valve, the ball valve opening may be set to a very small opening and the fluid may flow slightly, but it is difficult to set the opening and the external force on the handle unexpectedly. 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 is such that a sub-flow passage smaller in diameter than the main flow passage is formed at a position orthogonal to the main flow passage formed in the ball of the ball valve.

JP-A-11-270711 JP-A-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 entirely contacts 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, there is a possibility that foreign matter accumulates in a gap generated by the wear or a fluid stays to propagate germs. 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, the thickness of the drill needs to be set so as not to be broken when the sub flow passage is cut, and there is a possibility that a flow rate larger than a desired flow rate may flow. In particular, when the fluid is expensive, the cost of the fluid flowing for preventing the internal retention is increased in order to prevent the fluid from staying inside the pipe or the ball valve.

  An object of the present invention is to provide a ball valve capable of reducing the flow rate when flowing a fluid in order to solve the above-described problems of the prior art and prevent the generation of foreign matter and the retention of 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, a valve chamber communicating the first flow path and the second flow path, and the first flow path side in the valve chamber. A flow rate adjustment sheet positioned 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 the sheet and the flow rate adjustment sheet A ball valve having a through hole serving as a valve body flow path and having a through hole serving as a valve body flow path and communicating or blocking the first flow path and the second flow path, , An annular seat portion, and a flow rate adjustment portion located on the inner peripheral side of the seat portion, the seat portion includes a seal surface on which the ball valve body slides and seals the fluid, and the flow rate adjustment portion is A flow rate adjustment opening that communicates the second flow path and the valve chamber, and is continuously connected to the sealing surface. And a guide surface configured to guide the fluid while being spaced apart from the valve body, and a gap between the guide surface and the ball valve body continuously increases from the outer peripheral edge of the guide surface toward the flow path axis. A ball valve is provided.

  That is, in the first aspect of the present invention, the guide surface of the flow rate adjusting sheet is continuously connected to the seal surface and is separated from the ball valve body. Further, the gap between the guide surface and the ball valve body is continuously increased from the outer peripheral edge of the guide surface toward the channel axis. According to this aspect, the ball valve body and the flow rate adjusting unit can be brought into non-contact when the ball valve body rotates, so that the ball valve body does not slide in contact with the flow rate adjusting unit. Generation of foreign matter due to wear or sliding can be reduced. Furthermore, since the fluid flowing through the valve body flow path easily flows from the outer peripheral edge of the guide surface toward the center along the guide surface, a stagnant portion is less likely to occur in the gap between the guide surface and the ball valve body, and the gap is reduced. Flushing can be performed effectively, and foreign matter can be prevented from accumulating in the gap and generation of germs.

  According to the second aspect of the present invention, in the first aspect, the sealing surface is a spherical surface having the same radius as the radius of the ball valve body, and the guide surface is a spherical surface having a radius smaller than the radius of the ball valve body. A ball valve is provided.

  That is, since the guide surface becomes a spherical surface that swells toward the second flow path, the fluid flowing through the valve body flow path is more likely to flow along the outer peripheral edge of the guide surface, and the outer peripheral edge of the guide surface is flushed more effectively. it can.

  According to a third aspect of the present invention, in the first aspect or the second aspect, the seat member has a communication groove that communicates the first flow path and the valve chamber, and the ball valve body is a valve body flow path. A ball valve is provided that has an auxiliary flow path that is orthogonal to the valve body flow path and has an inner diameter smaller than that of the valve body flow path, and at least when in the fully closed state, the auxiliary flow path communicates the valve body flow path and the second flow path. Is done.

  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 even in the fully closed state, fluid can flow little by little in the ball valve. The retention of fluid in the valve chamber and the valve body flow path can be suppressed, and generation of germs, accumulation of foreign matters, adhesion, etc. can be reduced.

  According to the fourth aspect of the present invention, in the third aspect, the auxiliary flow path is a 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 connected to each other. There is provided a ball valve having a small-diameter channel having an inner diameter smaller than that of the radial channel, and the length of the small-diameter channel is shorter than that of the large-diameter channel.

  That is, the auxiliary flow path is formed in stages by a large diameter flow path and a small diameter flow path shorter than the large diameter flow path. This mode makes it difficult to break the drill used when drilling a small-diameter channel, and the outer diameter of the drill can be reduced, so that the inner diameter of the small-diameter channel can be reduced, and the flow rate for preventing retention in the ball valve can be reduced. it can.

  According to a fifth aspect of the present invention, there is provided the ball valve according to the fourth aspect, wherein the small diameter flow path has an inner diameter of 0.1 mm or more and less than 1 mm.

  According to this aspect, since the drill used when drilling the small-diameter channel is not easily broken, the small-diameter channel having an inner diameter of less than 1 mm can be stably drilled. In addition, since the inner diameter of the small-diameter channel is 0.1 mm or more, a fluid such as pure water can be stably passed through the small-diameter channel.

  According to the present invention, the contact area between the flow rate adjustment sheet and the ball valve body is reduced, and by increasing the gap between the flow rate adjustment sheet and the ball valve body as approaching the flow path axis, foreign matter is generated, A ball valve that can prevent fluid from staying in the gap can be provided. Further, a communication groove that communicates the first flow path and the valve chamber is formed in the seat, and an auxiliary flow path that communicates the valve body flow path and the second flow path is formed in the ball valve body with a relatively large-diameter hole and a relatively large diameter. By forming in steps with small-diameter holes, it is possible to provide a ball valve that can prevent the fluid from staying in the ball valve with a small flow rate.

It is sectional drawing which shows the fully open state of the ball valve which concerns on 1st embodiment of this invention. It is drawing which shows the flow volume adjustment sheet | seat 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 principal part expansion AA sectional drawing which shows each opening degree state of the ball valve which concerns on 1st embodiment of this invention, (a) is drawing which shows a fully closed state, (b) is a half-open state. It is drawing which shows, (c) is drawing which shows a fully open state. It is a side view from the 2nd channel side of the ball valve concerning a first embodiment of the present invention. It is a principal part expanded sectional view 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, (a) is drawing which shows the state which drilled the large diameter flow path. (B) is drawing which shows the state which perforated the small diameter channel.

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

  FIG. 1 is a 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 in the ball valve according to the first embodiment, and FIG. FIG. 4 is an enlarged cross-sectional view of the main part showing the respective opening states 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 includes a valve body 1, a ball valve body 2 disposed inside the valve body 1, and a first flow of the valve body 1 so as to be in constant contact with the ball valve body 2. The flow rate of the fluid flowing through the first flow path 11 and the second flow path 12 is positioned on the second flow path 12 side of the valve body 1 so as to always contact the seat 3 located on the path 11 side and the ball valve body 2. And a flow rate adjustment sheet 4 configured to be adjusted. The ball valve body 2 is connected to a handle 6 which is an operation unit via a stem 5. The ball valve body 2 rotates following the rotation of the handle 6 to communicate or block 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 includes a first channel 11, a second channel 12 having the same channel axis as the first channel 11, and the first channel 11 and the second channel 12. And a valve chamber 13 communicating therewith. An annular recess 14 centered on the channel axis is formed on the wall surface of the valve chamber 13 on the second channel 12 side, and the flow rate adjusting sheet 4 is inserted 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 into the annular groove 10. A cutout groove 15 is formed on the outer peripheral edge of the recess 14 so as to protrude toward the outer periphery in the radial direction of the recess 14. A through hole into which the stem 5 is inserted is communicated with the valve chamber 13 in a direction intersecting with the flow path axis of the valve body 1. Male screw portions are formed on the outer peripheral surfaces of both ends of the valve body 1, and female screw 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 engagement groove having a trapezoidal cross section for engaging the stem 5 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 serving as the valve body passage 21 is formed.

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

  The valve body retainer 9 is made of PVC and has a cylindrical shape. The seat 3 and the 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 disposed on the other end surface of the valve body retainer 9. An O-ring is disposed on the outer peripheral surface of one end of the valve body retainer 9, and a male thread portion that is screwed to the female thread portion of the valve body is disposed on the outer peripheral surface of the other end portion of the valve body retainer 9. Is formed. By screwing the valve body presser 9 into 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 seat 4 and the seat 3 through the first cushion 16 and the second cushion 17 from both flow paths in the valve chamber 13, respectively.

  The sheet 3 is made of polytetrafluoroethylene (hereinafter referred to as PTFE) and has an annular disk shape. The seat 3 is disposed in the valve chamber 13, and the center of the seat 3 is located on the flow path axis. The seat 3 includes a seal surface 31 on which the ball valve body 2 slides and seals the fluid, and the seal surface 31 is formed as an inclined surface that is a conical surface. By making the sealing surface 31 a conical surface, the contact between the ball valve body 2 and the sealing surface 31 can be a 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 adjustment sheet 4 is disposed in the valve chamber 13, and the center of the flow rate adjustment sheet 4 is located on the flow path axis. The flow rate adjustment sheet 4 includes an annular seat portion 42 that is fitted into an annular recess 14 disposed in the valve chamber 13, and a flow rate adjustment portion 44 that is positioned on the inner peripheral side of the seat portion 42. . A protrusion 41 is formed on the outer peripheral edge of the flow rate adjustment sheet 4 and is fitted into the notch groove 15 formed in the recess 14 of the valve chamber 13. The protrusion 41 prevents the flow rate adjustment sheet 4 from rotating when the flow rate adjustment sheet 4 is inserted into the valve body 1.

  Similar to the seat 3, the seat portion 42 includes a seal surface 43 on which the ball valve body 2 slides and seals the fluid. The seal surface 43 is formed to be a spherical surface having a radius substantially the same as the radius R1 of the ball valve body 2. Thus, when the sealing surface 43 is a spherical surface instead of a conical surface, the contact between the ball valve body 2 and the sealing surface 43 is a 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 a half-open state. Therefore, when the ball valve is in a half-open state, the ball valve body 2 is pressed against the seal surface 43 and seals. It can reduce that the surface 43 is damaged or the ball valve body 2 bites in. Here, when the outer shape such as the thickness of the sheet 3 is made substantially the same as the shape of the sheet portion 42, the sheet 3 can be fitted into the recess 14 like the flow rate adjustment sheet 4, so that there is no standard flow rate adjustment function. In the specification, the sheet 3 can be inserted into the recess 14 instead of the flow rate adjustment sheet 4, which is preferable.

  A cylindrical projection 45 having a slightly smaller diameter than the second channel 12 is formed on the second channel 12 side of the flow rate adjusting unit 44. Since the protrusion 45 is fitted in the second flow path 12, the thickness of the flow rate adjusting unit 44 can be increased while suppressing the change in the overall length of the ball valve, and the strength of the flow rate adjusting sheet 4 can be secured. The flow rate adjusting portion 44 is formed with a flow rate adjusting opening 46 that communicates with the second flow path 12 and the valve chamber 13 and adjusts the flow rate of the ball valve. The flow rate adjustment 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 adjustment 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 adjustment opening 46 in the flow rate adjustment sheet 4 instead of the ball valve body 2, the processing is easier than in the case of forming the flow rate adjustment opening 46 in the ball valve body 2, and the bulk of the parts inventory is increased. Can be reduced. In particular, when the flow rate adjusting sheet 4 is formed of PTFE, it can be applied to many use conditions with one kind of material, so that the number of parts in stock can be reduced.

  The flow rate adjusting unit 44 is continuously connected to the seal surface 43 and formed with a guide surface 47 that guides fluid to the second flow path 12. The guide surface 47 is formed as 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.2 (c), the radius R2 of the guidance surface 47 is made easy to understand with the virtual line. The guide surface 47 is formed so as to approach the surface on the second flow path 12 side of the flow rate adjustment sheet 4 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 portion of the cap nut 7, a female screw portion that is screwed to the male screw portion formed at both ends of the valve body 1 is formed, and on the other end portion of the cap nut 7. An inner flange portion protruding toward the inner diameter side is formed. The flanged short tube 8 is made of PVC, and an outer flange portion projecting to the outer diameter side is formed at one end portion. The flanged short tube 8 is sandwiched and fixed by cap nuts 7 on both end faces of the valve body 1.

  Next, with reference to FIGS. 1-4, the effect | action of the ball valve of 1st embodiment is demonstrated. When the handle 6 of the ball valve is rotated, the stem 5 is rotated following the handle 6 and the ball valve body 2 is rotated 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. 3 a), the ball valve body 2 is in a half-open state (FIG. 3 b), and the first flow path 11 and the second flow path 12 are communicated by the valve body flow path 21. The fluid flowing through the valve body flow path 21 flows along the guide surface 47 from the outer peripheral edge of the guide surface 47 and flows into the flow rate adjusting opening 46. When the ball valve body 2 is further rotated, the valve is fully opened (FIG. 3c). The opening S (see FIG. 4) formed by the valve body flow path 21 and the flow rate adjustment opening 46 changes according to the rotation of the ball valve body 2, and the opening S increases as the rotation amount of the ball valve body 2 increases. The area of is also increased.

  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 when 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 accompanying 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, an operation torque equivalent to that of a general ball valve not provided with the flow rate adjusting unit 44 can be achieved. In addition, 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. Accordingly, the fluid flowing through the valve body passage 21 is likely to flow from the outer peripheral edge of the guide surface 47 toward the center along the guide surface 47, so that the stay portion is present in the gap 25 (particularly in the vicinity of the outer peripheral edge of the guide surface 47). Less likely to occur. The ball valve is prone to foreign matter accumulating 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, and it is easy for bacteria to be accumulated due to fluid retention. By setting the state, the entire gap 25 can be flushed and cleaned effectively.

  In the first embodiment, the flow rate adjustment opening 46 is generally formed in a fan shape, but the shape of the flow rate adjustment opening 46 can be selected as appropriate depending on what kind of flow adjustment is performed. Shape, right trapezoid and so on. The number of openings for forming the flow rate adjusting opening 46 is not limited to one, and the flow rate adjusting opening 46 may be formed by a plurality of holes.

  In the first embodiment, the sealing surface 31 of the seat 3 is formed as an inclined surface that is a conical surface, but is substantially the same as the radius R1 of the ball valve body 2 as with the sealing surface 43 of the flow rate adjusting seat 4. You may form so that it may become a spherical surface which has a radius. Further, the sealing surface 43 of the flow rate adjusting sheet 4 is formed to be a spherical surface having a radius substantially the same as the radius R1 of the ball valve body 2, but, like the sealing surface 31 of the seat 3, is a conical surface. You may form with 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 only needs to increase as it approaches the axis. Other shapes include a conical surface, a pyramidal surface, an ellipsoidal surface, a combination of a plurality of curved surfaces and a tapered surface, but the outer peripheral edge of the guide surface 47 is formed with a curved surface that swells in the direction of the second flow path 12. Is preferred. By doing in this way, the fluid flowing through the valve body flow path 21 becomes easier to flow along the outer peripheral edge of the guide surface 47, and the outer peripheral edge of the guide surface 47 can be flushed more effectively.

  Next, a ball valve according to a second embodiment of the present invention will be described with reference to FIGS. 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 in the ball valve according to the second embodiment. It is sectional drawing which shows the method of punching. The second embodiment is different from the first embodiment mainly in that an auxiliary flow path 22 for preventing fluid from staying inside the ball valve is formed. In addition, in FIGS. 5-6, the code | symbol same as FIGS. 1-4 is attached | subjected to the component which has the effect | action and function similar to 1st embodiment, and the difference with 1st embodiment is mainly demonstrated below. explain.

  In the second embodiment, a communication groove 32 that always communicates the first flow path 11 and the valve chamber 13 is formed on the outer peripheral edge of the seat 3. In addition, a communication hole serving as an auxiliary flow path 22 orthogonal to the valve body flow path 21 is formed in the rotational 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 and shorter than the large diameter flow path 23.

  As a processing method of the communication hole to be the auxiliary flow path 22, first, a bottomed hole to be the large diameter flow path 23 is formed with a drill having an outer diameter of 4 mm from the outer peripheral surface of the ball valve body 2 toward the valve body flow path 21. . If the bottom surface of the large-diameter channel 23 is formed so as to be narrowed toward the valve body channel 21, it is preferable because the drill for forming the small-diameter channel 24 can be easily positioned. Next, a through-hole that becomes the small-diameter channel 24 is formed with a drill having an outer diameter of 0.3 mm from the center of the bottom surface of the large-diameter channel 23 toward the valve body channel 21. The processing method for forming the auxiliary flow path 22 in stages by the large diameter flow path 23 and the small diameter flow path 24 is easy to break the drill used for drilling the small diameter flow path 24. The inner diameter of the small diameter flow path 24 is less than 1 mm. It is suitable at the time. Further, when a through-hole is drilled on the outer peripheral surface of the ball valve body 2 with a thin drill, the drill is slippery and easily breaks as the through-hole becomes longer, but the auxiliary channel 22 is divided into a large-diameter channel 23 and a small-diameter channel 24. If the length of the small-diameter flow path 24 is shortened by forming them separately, the through hole can be easily processed. In particular, if the inner diameter of the small-diameter channel 24 is less than 1 mm, the drill is easy to break. Therefore, if the length of the small-diameter channel 24 is 3 mm or less, the drill is difficult to break and easy to process. Further, the inner diameter of the small-diameter channel 24 is preferably set to 0.1 mm or more so that a fluid such as pure water passes through the small-diameter channel 24 stably. 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 is omitted.

  Next, the operation of the ball valve of the second embodiment will be described with reference to FIGS. 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 fluid in the valve chamber 13 and the valve body channel 21 can be suppressed, generation of germs, accumulation of foreign matter, and adhesion. Can be reduced. At this time, since the auxiliary channel 22 is formed stepwise by the large-diameter channel 23 and the small-diameter channel 24, the inner diameter of the small-diameter channel 24 can be reduced, and the flow rate for the purpose of preventing stagnation can be suppressed. Other operations and effects of the ball valve according to the first embodiment are the same as those of the ball valve according to the first embodiment, and thus description thereof is omitted.

  In the second embodiment, the auxiliary flow path 22 is formed by a drill, but 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 configured by only the small diameter flow path 24. It becomes easy. Further, only the large-diameter channel 23 of the auxiliary channel 22 may be formed by injection molding. In the second embodiment, the number of the communication grooves 32 and the auxiliary flow paths 22 is one each, but the number of the communication grooves 32 and the auxiliary flow paths 22 can be freely designed according to the desired flow rate. it can.

  In the present invention, the material of the valve body 1, the stem 5, the ball valve body 2, the valve body presser 9, the seat 3, the flow rate adjustment sheet 4, the handle 6, the cap nut 7, and the flanged short tube 8 is A material satisfying functions such as chemical resistance to fluid can be selected as appropriate. Examples of suitable materials include resins such as PVC, polypropylene, polyethylene, polyvinylidene fluoride, ABS, and PTFE, metals such as stainless steel, iron, copper alloys, and aluminum, or ceramics such as porcelain.

  Preferred embodiments of the present invention are as described above, but the present invention is not limited to them. Various other embodiments may be made without departing from the spirit and scope of the invention. Furthermore, the operations and effects described in this embodiment are merely examples, and do not limit the present invention.

DESCRIPTION OF SYMBOLS 1 Valve body 2 Ball | bowl valve body 3 Seat 4 Flow rate adjustment sheet 5 Stem 6 Handle 7 Cap nut 8 Short tube with a flange 9 Valve body presser 10 Annular groove 11 First flow path 12 Second flow path 13 Valve chamber 14 Recess 15 Notch groove 16 First cushion 17 Second 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 part 42 Sheet part 43 Seal surface 44 Flow rate adjustment part 45 Protrusion part 46 Flow rate Adjustment opening 47 Guide surface

Claims (5)

A valve body comprising a first flow path, a second flow path, and a valve chamber communicating the first flow path and the second flow path;
A seat located on the first flow path side in the valve chamber;
A flow rate adjustment sheet positioned on the second flow path side in the valve chamber and configured to adjust the flow rate of fluid flowing through the first flow path and the second flow path;
A ball valve body that is rotatably disposed between the seat and the flow rate adjustment sheet, has a through-hole serving as a valve body passage, and communicates or blocks the first passage and the second passage; In a ball valve comprising:
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 seal surface on which the ball valve body slides and seals the fluid,
The flow rate adjustment unit is continuously connected to the flow rate adjustment opening that communicates the second flow path and the valve chamber, and is separated from the ball valve body and induces the fluid. A guiding surface configured,
The ball valve characterized in that a gap between the guide surface and the ball valve body continuously increases from the outer periphery of the guide surface toward the flow path axis. The sealing surface is a spherical surface having the same radius as the radius of the ball valve body;
The ball valve according to claim 1, wherein the guide surface is a spherical surface having a radius smaller than a radius of the ball valve body. The seat member has a communication groove communicating the first flow path and the valve chamber;
The ball valve body has an auxiliary flow path that is orthogonal to the valve body flow path and has an inner diameter smaller than that of the valve body flow path. The ball valve according to claim 1, wherein the second flow path is communicated with the ball valve. The auxiliary channel is a large-diameter channel located on the outer peripheral side of the ball valve body, and a small-diameter channel having an inner diameter smaller than the large-diameter channel that communicates the large-diameter channel and the valve-body channel; Have
The ball valve according to claim 3, wherein a length of the small-diameter channel is shorter than the large-diameter channel.   The ball valve according to claim 4, wherein an inner diameter of the small-diameter channel is 0.1 mm or more and less than 1 mm.

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