JP4229378B2 - Butterfly valve - Google Patents

Description

  The present invention relates to a butterfly valve provided with an annular valve seat that is in close contact with the peripheral edge of a valve body in a closed posture within a substantially cylindrical valve box.

  As an attachment structure of the annular valve seat in this type of butterfly valve, Patent Document 1 discloses that the annular valve seat is overlapped on one opening end surface of the valve casing, and the valve casing and the annular ring are formed by a plurality of bolts. A configuration for fastening the valve seat is disclosed.

Moreover, in patent document 2, in the state which inserted the annular valve-seat sheet | seat between one opening end surface in a valve box, and the cyclic | annular pressing body which overlaps with this, a valve box and a holding body are used with several bolts. The structure of sandwiching and fixing the annular valve seat is disclosed.
JP 2000-266193 A (FIG. 2) Japanese Patent Publication No. 8-14329 (FIG. 1)

  By the way, in the state where the butterfly valve is sandwiched and fixed between the pipes, the opening end face of one pipe and the surface facing the opening end face of the one pipe out of the annular valve seat or the presser The pressure contact (adhesion) is made through a sealing gasket.

  However, in the configuration of Patent Document 1, a bolt for fastening the annular valve seat and the valve box is screwed from the surface side of the annular valve seat toward the valve box. Bolt holes are opened.

  In this case, the bolt hole portion of the surface of the annular valve seat does not adhere to the gasket (a space is formed), so the pressure contact force (surface pressure) received by the gasket sandwiched between the pipe and the annular valve seat is The part corresponding to the bolt hole is smaller than the other part. That is, the pressure contact force applied to the gasket varies depending on the location.

  For this reason, in the structure of the said patent document 1, there existed a possibility that a fluid might leak from between one piping and an annular valve seat sheet | seat, without a gasket exhibiting sufficient sealing function.

  Similarly, in the configuration of Patent Document 2, since the bolt hole for screwing the bolt is opened on the surface of the presser body, the pressure contact force applied to the gasket varies depending on the location due to the bolt hole. As in the case of Patent Document 1, there is a risk that fluid may leak from between one pipe and the presser.

  Therefore, it is a technical object of the present invention to provide a butterfly valve that reliably prevents fluid from leaking from between a pipe and an annular valve seat or a presser.

In order to achieve this technical problem, the invention of claim 1 includes a substantially cylindrical valve box sandwiched and fixed between pipes, and an opening / closing rotation for adjusting the flow of fluid in the valve box . A butterfly valve comprising a valve body capable of being closed and an annular seat seat in close contact with the peripheral edge of the valve body in a closed posture, and a flange projecting radially outward at one opening end of the valve box was formed over the entire circumference, the surface facing the open end face of the one pipe of the flange, the annular valve seat sheet disposed so as to surround the opening of the valve body, the flange, A plurality of through holes penetrating in a direction parallel to the axes of the two pipes are formed, and a mounting hole corresponding to each through hole of the flange is formed on the back surface of the annular valve seat, which is in contact with the surface of the flange. To open only towards the surface of the flange Formed, the a annular valve seat surface a flat surface of the sheet, each mounting hole of said annular valve seat sheet, through the through hole of the flange corresponding thereto, inserted and fixed mounting means from the back side of the flange By connecting the flange and the annular valve seat, the flat end surface of the annular valve seat is brought into pressure contact with the opening end surface of the one pipe via the first sealing gasket , The other open end face of the valve box is brought into pressure contact with the open end face of the pipe via the second sealing gasket .

The invention of claim 2 is a substantially cylindrical valve box sandwiched and fixed between pipes, a valve body that can be opened and closed to adjust the flow of fluid in the valve box, and a closed posture. A butterfly valve having an annular valve seat seat in close contact with the peripheral edge of the valve body, wherein a flange projecting radially outward is formed over the entire circumference at one open end of the valve box. An annular pressing body is disposed on the surface facing the opening end face of the one of the pipes so as to surround the opening of the valve box, and the annular pressing body is disposed between the flange surface and the pressing body. The valve seat is inserted, and the flange has a plurality of through holes penetrating in a direction parallel to the axis of the two pipes, while the back surface of the presser body that contacts the surface of the flange is A mounting hole corresponding to each through hole of the flange is formed on the surface of the flange. Only then formed to open towards, the surface a flat surface of the pressing member, each mounting hole of the pressing member, through the through hole of the flange corresponding thereto, the back surface side of said mounting means flange by inserting fixed from and connecting the pressing member and the flange, the open end of the one pipe, is pressed against a flat surface of the pressing member via a first sealing gasket, the other pipe The other open end face of the valve box is pressed against the open end face of the valve box via a second sealing gasket .

  If comprised like Claim 1, on the back surface side contact | abutted on the surface (surface on the side which opposes the opening end surface of one piping) of a flange among annular valve seat sheets, the said flange and said annular valve seat sheet | seat are provided. Since the attachment hole for the attachment means to be connected is formed so as to open only toward the surface of the flange, the entire surface of the annular valve seat can be a flat surface having no holes or grooves. .

  As a result, when the butterfly valve is sandwiched and fixed between the two pipes, the flat opening end face of the one pipe and the entire flat surface of the annular valve seat are pressed against (adhered to) the sealing gasket. Therefore, a substantially uniform pressure contact force is applied to the gasket as a whole.

  Therefore, the gasket can sufficiently exhibit its sealing function, and it is possible to reliably prevent the fluid from leaking out between the one pipe and the annular valve seat.

  Moreover, when comprised like Claim 2, on the back surface side contact | abutted to the surface (surface on the side which opposes the opening end surface of one piping) of a flange among presser bodies, the said flange and the said presser body are provided. Since the mounting hole for the connecting mounting means is formed so as to open only toward the surface of the flange, the entire surface of the pressing body can be a flat surface having no holes or grooves.

  Therefore, in this case as well, when the butterfly valve is sandwiched and fixed between the two pipes, the flat opening end surface of the one pipe and the entire flat surface of the presser body are sealed together. Therefore, it is possible to reliably prevent the fluid from leaking from between the one pipe and the presser body.

  Next, an embodiment of the present invention will be described with reference to the drawings (FIGS. 1 and 2). FIG. 1 is a cross-sectional view of the butterfly valve of the first embodiment, and FIG. 2 is a cross-sectional view of the main part of the butterfly valve of the second embodiment.

  FIG. 1 shows a first embodiment of the present invention. The butterfly valve 1 according to the first embodiment includes a substantially cylindrical valve box 2 having an internal fluid passage 3, a substantially disc-shaped valve body 4 for opening and closing the fluid passage 3 of the valve box 2, and an annular shape And a valve seat 5.

  A valve rod 6 extending so as to intersect the axis A of the two pipes 21 and 22 located on both sides of the valve box 2 is pivotally supported on the valve box 2 so as to be rotatable about its own axis. In the first embodiment, the seal surface 8 of the valve body 4 is upstream of the flow direction of the fluid from the valve stem 6 (see the direction of arrow F in FIG. 1) so that the peripheral edge 7 of the valve body 4 is not blocked by the valve stem 6. The position is deviated appropriately (eccentric position). That is, the butterfly valve 1 of this embodiment is an eccentric type.

  A flange 9 protruding outward in the radial direction is formed over the entire circumference at one open end of the valve box 2 (the open end on the upstream side in the flow direction in the first embodiment). The flange 9 is formed with a step portion 10 that surrounds the outer peripheral side of the opening on the upstream side in the flow direction of the valve box 2.

  The flange 9 has a plurality of through holes 11 penetrating in a direction parallel to the axis A of both pipes (a direction parallel to the flow direction F) so as to communicate with the stepped portion 10 along the circumferential direction at appropriate intervals. Individually drilled. Each of these through holes 11 has a large diameter so that a head 16 of a mounting bolt 15 to be described later fits on the side of the flange 9 close to the back surface opposite to the stepped portion 10 (downstream in the flow direction in the first embodiment). Thus, on the side close to the step portion 10 (the upstream side in the flow direction in the first embodiment), a small diameter step is formed so that the shaft portion 17 of the mounting bolt 15 passes.

  An annular recessed groove 12 for fitting a sealing O-ring 18 to be described later is formed in a portion of the step portion 10 on the inner diameter side of each through hole 11.

  On the other hand, an annular valve seat 5 is fitted in the step portion 10 of the flange 9 in the valve box 2 so as to surround one opening (opening on the upstream side in the flow direction) of the valve box 2. In the first embodiment, the inner peripheral surface of the step portion 10 that contacts the annular valve seat 5 corresponds to the “flange surface” recited in the claims. In addition, the step part 10 is not an essential component of the flange 9 in the present invention.

  On the inner diameter side of the annular valve seat 5, a tongue piece 13 that protrudes radially inward is formed over the entire circumference. The fluid passage 3 in the valve box 2 is closed (the flow of fluid is blocked) by bringing the peripheral edge 7 of the valve body 4 into close contact with the inward tongue piece 13.

  Further, bolt holes 14 as mounting holes corresponding to the through holes 11 of the flange 9 are opened on the downstream side in the flow direction on the back surface of the annular valve seat 5 (the surface facing the inner peripheral surface of the step portion 10). It is formed to do. Therefore, each bolt hole 14 of the annular valve seat 5 is opened only toward the inner peripheral surface of the stepped portion 10. The surface of the annular valve seat 5 (the surface facing the upstream side in the flow direction so as to face the fixed flange 23 of the first pipe 21 described later) is a flat surface without holes or grooves.

  In a state where the annular valve seat 5 is fitted in the step portion 10 of the flange 9 in the valve box 2, a mounting bolt 15 is screwed into each bolt hole 14 of the annular valve seat 5 through each through hole 11 of the flange 9. In other words, by inserting the mounting bolt 15 from the back surface side (the end surface side opposite to the stepped portion 10) of the flange 9 toward the annular valve seat 5 by inserting, the annular valve seat 5 is It is detachably fixed to the valve box 2.

  The attachment bolt 15 corresponds to “attachment means” recited in the claims. Each mounting bolt 15 of the first embodiment is a hexagon socket head cap screw having a hexagon socket on the head 16.

  The annular valve seat 5 of the first embodiment may be made of metal or synthetic resin. Moreover, you may attach metal foil to the tongue piece part of the cyclic valve seat sheet | seat made from a synthetic resin. In the first embodiment, the back surface of the annular valve seat 5 is in close contact with the inner peripheral surface of the stepped portion 10 via a sealing O-ring 18 made of a soft elastic material such as rubber.

  As shown in FIG. 1, with the butterfly valve 1 interposed between the two pipes 21, 22, the fixing flanges 23, 24 that protrude radially outward from the opening ends of the pipes 21, 22 are connected to each other. The butterfly valve 1 is sandwiched and fixed by two pipes 21 and 22 by tightening with a plurality of sets of long screw bolts 25 and nuts 26.

  Between the fixed flange 23 of the first pipe 21 located on the upstream side in the flow direction and the surface facing the fixed flange 23 of the annular valve seat 5, an annular first seal gasket 27 made of a soft elastic material or the like is used. Is inserted. Similarly, between the fixed flange 24 of the second pipe 22 on the downstream side in the flow direction and the opening end surface of the valve box 2 facing the fixed flange 24 of the valve box 2, an annular first ring made of a soft elastic material or the like is used. A two-seal gasket 28 is inserted. The inner diameters of the sealing gaskets 27 and 28 are set to be substantially the same as the inner diameters of the pipes 21 and 22 corresponding to the gaskets 27 and 28, respectively.

  When configured as described above, when attaching the annular valve seat 5 to the valve box 2, the bolt hole 14 formed on the back surface of the annular valve seat 5 (the surface facing the inner peripheral surface of the step portion 10), Since the mounting bolt 15 is screwed from the back surface side of the flange 9 (the end surface side opposite to the step portion 10) toward the annular valve seat 5, the aforementioned bolt hole 14 is formed on the inner peripheral surface of the step portion 10. It only needs to be open toward. That is, it is not necessary to make a bolt hole 14 on the surface of the annular valve seat 5 (the surface facing the upstream side in the flow direction so as to face the fixed flange 23 of the first pipe 21). Therefore, the entire surface of the annular valve seat 5 can be a flat surface without holes or grooves.

  Thus, when the butterfly valve 1 is sandwiched and fixed between the pipes 21 and 22, the flat opening end face of the fixing flange 23 and the entire flat surface of the annular valve seat 5 in the first pipe 21 are Since the sealing gasket 27 can be pressed (contacted) from both sides, a substantially uniform pressing force is applied to the first sealing gasket 27 as a whole.

  Therefore, the first sealing gasket 27 can sufficiently exhibit its sealing function, and can reliably prevent fluid from leaking between the first pipe 21 and the annular valve seat 5. is there.

  In the first embodiment, the back surface of the annular valve seat 5 is in close contact with the inner peripheral surface of the step portion 10 via the sealing O-ring 18. It is also possible to prevent the fluid from leaking out. Of course, since the second sealing gasket 28 is also inserted between the fixed flange 24 of the second pipe 22 and the opening end face of the valve box 2 facing the fixed flange 24 of the second pipe 22, Needless to say, leakage of fluid from between the pipe 22 and the valve box 2 can be prevented.

  In the first embodiment, since the mounting bolt 15 is employed as the mounting means, the work of mounting / removing the annular valve seat 5 on the valve box 2 can be performed quickly and easily.

  FIG. 2 shows a second embodiment of the present invention. Here, in the second embodiment, the same configuration and operation as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof is omitted.

  In the butterfly valve 1 ′ of the second embodiment, an annular pressing body 29 ′ is fitted in the step portion 10 of the flange 9 in the valve box 2 so as to surround the opening on the upstream side in the flow direction of the valve box 2. Yes. An annular valve seat 5 'is interposed between the step portion 10 and the presser body 29'. By bringing the peripheral edge 7 of the valve body 4 into close contact with the annular valve seat 5 ', the fluid passage 3 in the valve box 2 is closed (flow of fluid is blocked).

  Bolt holes 30 ′ as attachment holes corresponding to the through holes 11 of the flange 9 are opened on the downstream side in the flow direction on the back surface of the presser body 29 ′ (surface facing the inner peripheral surface of the step portion 10). Is formed. Therefore, also in this case, each bolt hole 30 ′ of the annular valve seat 5 opens only toward the inner peripheral surface of the stepped portion 10. The surface of the presser 29 '(the surface facing the fixed flange 23 of the first pipe 21) is a flat surface without holes or grooves.

  With the annular valve seat 5 'interposed between the step 10 of the flange 9 and the presser 29' in the valve box 2, the bolt holes of the presser 29 'are inserted through the through holes 11 of the flange 9. By screwing the mounting bolt 15 into the 30 ', in other words, by screwing the mounting bolt 15 from the back side of the flange 9 toward the presser body 29', the presser body 29 'and thus the annular valve seat 5' It is detachably fixed to the box 2.

  The presser body 29 'of the second embodiment may be made of metal or synthetic resin. The annular valve seat 5 'may be made of metal or may be made of a synthetic resin having elasticity. When the presser 29 'is used, the annular valve seat 5' may have a laminated structure in which a plurality of metal plates are stacked. Further, the mounting bolt 15 may be configured to penetrate the annular valve seat 5 '.

  When configured as described above, the surface of the presser body 29 '(the surface facing the fixing flange 23 of the first pipe 21) can be a flat surface having no holes or grooves. Thus, when the butterfly valve 1 'is sandwiched and fixed between the pipes 21 and 22, the flat opening end face of the fixing flange 23 and the flat surface of the presser body 29' in the first pipe 21 are connected to the first seal. Since the first gasket 27 can be press-contacted (contacted) so as to be sandwiched from both sides, a substantially uniform pressing force is applied to the first seal gasket 27 as a whole.

  Accordingly, in this case as well, as in the first embodiment, the first sealing gasket 27 can sufficiently exert its sealing function, and fluid leaks from between the first pipe 21 and the presser 29 '. Can be reliably prevented.

  The present invention is not limited to the illustrated embodiment, and can be embodied in various forms. For example, the present invention is not limited to the pressure contact structure as in the above-described embodiments, that is, the pressure connection structure between the first pipe 21 on the upstream side in the flow direction and the valve box 2, but the second pipe on the downstream side in the flow direction. Needless to say, the invention can also be applied to the pressure contact structure between the valve 22 and the valve box 2. In this case, a flange projecting radially outward is provided at the opening end of the valve box 2 on the downstream side in the flow direction. Further, the attaching means is not limited to bolts, but may be pins, rivets or screws.

It is sectional drawing of the butterfly valve in 1st Example. It is principal part sectional drawing of the butterfly valve in 2nd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1 'Butterfly valve 2 Valve box 4 Valve body 5, 5' Annular valve seat 9 Flange 10 Step part 11 Through-hole 13 Tongue piece part 14 Bolt hole 15 Mounting bolt 21 and 22 as attachment means Piping 27 and 28 Seal Gasket 29 'Presser body

Claims (2)

Closely attached to the peripheral edge of the valve body in a closed position, a substantially cylindrical valve box that is sandwiched and fixed between the pipes, a valve body that can be opened and closed to adjust the flow of fluid in the valve box , and a closed valve body A butterfly valve with an annular seat seat
A flange projecting radially outward is formed on one opening end of the valve box over the entire circumference, and a surface of the flange facing the opening end surface of the one pipe is formed on the opening of the valve box. The annular seat seat so as to surround
The flange is formed with a plurality of through-holes penetrating in a direction parallel to the axis of the two pipes, and on the back surface of the annular valve seat that is in contact with the surface of the flange, each through-hole of the flange is formed. Is formed so as to open only toward the surface of the flange, and the surface of the annular valve seat is a flat surface,
The flange and the annular valve seat are connected to each mounting hole of the annular valve seat by inserting and fixing the mounting means from the back side of the flange through the corresponding through-hole of the flange. And
A flat surface of the annular valve seat is pressed against the open end surface of the one pipe via a first seal gasket, and the valve is connected to the open end face of the other pipe via a second seal gasket. A butterfly valve characterized in that the other open end face of the box is brought into pressure contact . Closely attached to the peripheral edge of the valve body in a closed position, a substantially cylindrical valve box that is sandwiched and fixed between the pipes, a valve body that can be opened and closed to adjust the flow of fluid in the valve box, and a closed valve body A butterfly valve with an annular seat seat
A flange projecting radially outward is formed on one opening end of the valve box over the entire circumference, and a surface of the flange facing the opening end surface of the one pipe is formed on the opening of the valve box. An annular presser body is disposed so as to surround, and the annular valve seat is interposed between the surface of the flange and the presser body,
The flange is formed with a plurality of through holes penetrating in a direction parallel to the axis of the two pipes, and the back surface of the presser body that contacts the surface of the flange corresponds to each through hole of the flange. Forming the mounting hole to open only toward the surface of the flange, the surface of the presser body is a flat surface,
By connecting and fixing the attachment means from the back side of the flange to the respective attachment holes of the presser body through the corresponding through-holes of the flange, the flange and the presser body are connected,
A flat surface of the presser body is pressed against the opening end face of the one pipe via a first sealing gasket, and the opening end face of the other pipe is attached to the valve box via a second sealing gasket. A butterfly valve characterized in that the other opening end face is brought into pressure contact .

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