Butterfly valve

Abstract

The purpose of the present invention is to provide a butterfly valve capable of obtaining a stable and high compression surface pressure. The present invention is provided with a rotation / movement conversion mechanism (MD) that rotates a valve body (50) as a valve stem (40) rotates from an open valve position to 90 degrees, and that moves the valve body (50) along a flow path (F) from an axial center so as to come into close contact with a seat ring (20) by rotating the valve stem (40) beyond 90 degrees, the rotation / movement conversion mechanism (MD) comprising: a cam (80) that moves the valve body (50) along the flow path (F) from the axial center; the main body is provided with an arc-shaped part (84) with a relatively long diameter; and a cam groove (54) into which the cam (80) is fitted, and the valve body (50) is moved from the axial center along the flow path (F) so as to come into close contact with the seat ring (20) along the flow path (F) by rotating the valve rod (40) by more than 135 degrees to disengage the arc-shaped portion (84) from the large arc-shaped portion (543) of the cam groove (54) and press-fit the linear portion (542).

Description

Technical Field

[0001] The present invention relates to, for example, a butterfly valve that is connected to piping and, by opening and closing, adjusts the flow of fluid within the piping or switches between opening and closing the flow of fluid within the piping. Background Technology

[0002] Conventionally, as shown in Patent Document 1, a butterfly valve is used, which includes: a valve housing having a tubular flow path; a valve stem rotatably disposed on the valve housing; a valve body that rotates via the valve stem to open and close the flow path; and a seat ring disposed between the valve housing and the valve body. This butterfly valve adjusts the flow rate of fluid by opening and closing, or switches between opening and cutting off the flow of fluid.

[0003] However, the butterfly valve shown in Patent Document 1 closes the valve body against the seat ring to cut off the flow when the valve is closed. Therefore, when cutting off the flow of fluids with small molecular size such as hydrogen and helium, or extremely low temperature fluids such as cryogenic fluids, it is necessary to increase the compression surface pressure between the seat ring and the valve body, but it is difficult to stably maintain a high compression surface pressure.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2003-185047 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] The purpose of this invention is to provide a butterfly valve that can achieve a stable and high compression surface pressure.

[0009] Methods for solving problems

[0010] This invention relates to a butterfly valve, characterized by comprising: a valve housing having a tubular flow path; a valve stem rotatably disposed on the valve housing; a valve body that rotates via the valve stem to open and close the flow path; and a seat ring disposed between the valve housing and the valve body. A rotational movement switching mechanism is provided between the valve stem and the valve body. This mechanism causes the valve body to rotate along with the valve stem as it rotates from the open position to a predetermined angle, and the valve body moves in close contact with the seat ring by rotating the valve stem beyond the predetermined angle. The motion conversion mechanism includes: a cam body disposed on either the valve stem or the valve body, having a convex portion whose diameter is longer than that of the other portion in the circumferential direction; and a cam groove disposed on either the valve stem or the valve body for the cam body to be inserted into. The cam groove is provided with: a recess corresponding to the convex portion; and a pressing surface continuous with the recess and pressed into by the convex portion. By rotating the valve stem beyond the predetermined angle, the convex portion disengages from the recess and presses into the pressing surface, causing the valve body to move along the flow path from the axis of the valve stem in a manner that is in close contact with the seat ring.

[0011] The butterfly valve mentioned above can be a center-type butterfly valve, or it can be configured as a single-eccentric butterfly valve or a double-eccentric butterfly valve.

[0012] The aforementioned valve housing is sometimes also referred to as the valve body, housing, or valve body.

[0013] The aforementioned seat ring is sometimes also referred to as a valve seat, etc.

[0014] As long as the aforementioned rotary movement conversion mechanism can enable the valve body to move in close contact with the aforementioned seat ring, its movement direction can be along the fluid flow direction or in a direction intersecting the flow direction.

[0015] According to the present invention, a stable and high compression surface pressure can be obtained.

[0016] Specifically, the rotary movement switching mechanism in the butterfly valve, which opens and closes the flow path of the valve housing by rotating the valve body using the valve stem to abut against the seat ring, can cause the valve body to rotate along with the valve stem as it rotates from the valve opening position to a predetermined angle, and can cause the valve body to move in close contact with the seat ring by rotating the valve stem beyond the predetermined angle.

[0017] Additionally, the rotary movement conversion mechanism includes: a cam body disposed on either the valve stem or the valve body, having a protrusion whose diameter in the circumferential direction is longer than that of the other portion; and a cam groove disposed on either the valve stem or the valve body for the cam body to be inserted into, wherein the cam groove has: a recess corresponding to the protrusion; and a pressing surface continuous with the recess and pressed into by the protrusion. Therefore, by rotating the valve stem beyond the predetermined angle, the protrusion disengages from the recess and presses into the pressing surface, causing the valve body to move in close contact with the seat ring.

[0018] Therefore, in the closed state, the valve body and the seat ring are in close contact under a high compressive surface pressure. Thus, even when cutting off the flow of fluids with small molecular sizes or extremely low temperatures such as cryogenic fluids, the fluid will not flow out between the seat ring and the valve body, reliably cutting off the flow path.

[0019] As an embodiment of the present invention, a rotation limiting mechanism may be provided, which allows the valve body to rotate from the valve stem's open position to the predetermined angle, limits the rotation of the valve body accompanying the valve stem's rotation beyond the predetermined angle, and allows the valve body to move in the direction of close contact with the seat ring.

[0020] According to the present invention, the rotation limiting mechanism can limit the rotation of the valve body that accompanies the rotation of the valve stem exceeding the predetermined angle, while in the closed state, the rotation movement conversion mechanism can move the valve body in a direction that is in close contact with the seat ring, thereby reliably cutting off the flow path.

[0021] Alternatively, as an embodiment of the present invention, the rotary movement conversion mechanism and the rotary restriction mechanism may be disposed on opposite sides of the valve body along the axial direction of the axis, and a transmission component may be provided. This transmission component transmits the rotational force of the valve stem to the rotary movement conversion mechanism and the rotary restriction mechanism disposed on opposite sides of the valve body along the axial direction, on the side of the rotary movement conversion mechanism and the rotary restriction mechanism on which no rotational force is input from the valve stem.

[0022] According to the present invention, the transmission member enables the transmission of the valve stem's rotational force to the side of the rotational movement conversion mechanism and the rotational limiting mechanism disposed on both sides of the valve body in the axial direction, on the side where no rotational force is input from the valve stem. Therefore, by means of the rotational movement conversion mechanism and the rotational limiting mechanism disposed on both sides of the axial direction, the rotation of the valve body accompanying a rotation of the valve stem exceeding the predetermined angle can be restricted. Simultaneously, in the closed state, the rotational movement conversion mechanism moves the valve body in a direction that brings it into close contact with the seat ring, further reliably cutting off the flow path.

[0023] Alternatively, as an embodiment of the present invention, a side portion may be provided in a part of the transmission component, which moves closer to the axis in a predetermined direction to suppress the reduction of the flow path area in the open valve state.

[0024] According to the present invention, without reducing the flowability in the open valve state, the valve body can be moved in a direction that is in close contact with the seat ring by the rotary movement conversion mechanism in the closed valve state, thereby further reliably cutting off the flow path.

[0025] Specifically, the axis, which serves as the center of rotation for the rotating valve stem and valve body, is positioned to traverse the tubular flow path cut off by the valve body in the closed position. Therefore, when the transmission component, which transmits the rotational force of the valve stem to the side of the rotational movement conversion mechanism and the rotational restriction mechanism located on both sides of the valve body relative to the axis, is positioned at the axis, it traverses the flow path, reducing the flow area and decreasing the flowability in the open valve state. In contrast, a portion of the transmission component is provided with a side portion that approaches the axis in a predetermined direction, thus suppressing the reduction in flow area in the open valve state. This suppresses the decrease in flowability caused by the transmission component in the open valve state, while in the closed valve state, the rotational movement conversion mechanism moves the valve body in a direction that brings it into close contact with the seat ring, further reliably cutting off the flow path.

[0026] Alternatively, as an embodiment of the present invention, an over-rotation limiting part may be provided, which limits the over-rotation of the valve stem.

[0027] According to the present invention, further rotation of the valve stem from at least one of the closed and open positions can be prevented. Therefore, excessive rotation of the valve stem can prevent loads from being applied to the valve stem, the valve body, or the seat ring.

[0028] Alternatively, as a method of the present invention, the valve stem can be rotated by a predetermined angle to move the valve body by utilizing the rotational load generated by the contact between the valve body and the seat ring.

[0029] According to the present invention, rotation of the valve body that accompanies rotation of the valve stem exceeding the predetermined angle can be restricted without the need for a rotation limiting mechanism. Simultaneously, in the closed state, the valve body can be moved in a direction that closely contacts the seat ring, reliably cutting off the flow path. Therefore, compared to the case where a rotation limiting mechanism is provided, the butterfly valve can be constructed with a simpler structure.

[0030] Furthermore, the present invention is a butterfly valve, characterized by comprising: a valve housing having a tubular flow path; a valve stem rotatably disposed on the valve housing; a valve body rotating via the valve stem to open and close the flow path; and a seat ring disposed between the valve housing and the valve body. A rotational movement conversion mechanism is disposed between the valve stem and the valve body. This mechanism causes the valve body to rotate along with the valve stem as it rotates from the open position to a predetermined angle, and moves the valve body in close contact with the seat ring by rotating the valve stem beyond the predetermined angle. The direction in which the rotational movement conversion mechanism causes the valve body to move in close contact with the seat ring is defined as the movement direction, and the opposite direction is defined as the reverse movement direction. The rotational movement conversion mechanism comprises: a cam body disposed on... Either the valve stem or the valve body; and a cam groove disposed on the other of the valve stem and the valve body for the cam body to be embedded in, the cam groove having abutting portions spaced at predetermined intervals along the direction of movement, the cam body having at least two arcuate portions centered on an eccentric center, the eccentric center being eccentric relative to the axis that is the rotation center of the valve stem, the two arcuate portions being arranged in opposite orientations across the eccentric center, and the length of the imaginary line connecting the two arcuate portions passing through the eccentric center being set to be equal to the predetermined interval, by the rotation of the valve stem exceeding the predetermined angle, the abutting portions spaced at the predetermined intervals in the cam groove abut against the two arcuate portions, causing the valve body to move from the axis along the flow path in a manner that is in close contact with the seat ring.

[0031] The butterfly valve mentioned above can be a center-type butterfly valve, or it can be configured as a single-eccentric butterfly valve or a double-eccentric butterfly valve.

[0032] The aforementioned valve housing is sometimes also referred to as the valve body, housing, or valve body.

[0033] The aforementioned seat ring is sometimes also referred to as a valve seat, etc.

[0034] As long as the aforementioned rotary movement conversion mechanism can enable the valve body to move in close contact with the aforementioned seat ring, its movement direction can be along the fluid flow direction or in a direction intersecting the flow direction.

[0035] The aforementioned cam groove has abutting portions spaced at predetermined intervals along the direction of movement, and can be any top-view shape as long as the cam body is inserted in a rotatable manner.

[0036] The arc shape centered on the aforementioned eccentric center includes various curved shapes such as circular arcs, elliptical arcs, and oblong arcs that protrude in a specified direction when viewed from above, and may also have inflection points.

[0037] The contact portion can be in contact with the arc-shaped surface, or it can be in line contact or point contact.

[0038] In addition, the arc-shaped part can make direct contact with the part being contacted, or it can make contact through other parts, and it can also have a small gap with tolerance.

[0039] In addition, the cam body has at least two arc-shaped portions centered on an eccentric center, which is eccentric relative to the axis that serves as the rotation center of the valve stem. The portions other than the arc-shaped portions can be straight, arc-shaped centered on the axis, arc-shaped with a center different from the axis and the eccentric center, or a combination thereof.

[0040] Furthermore, the at least two arc-shaped portions centered on the eccentric center can have different diameters or the same diameter.

[0041] The imaginary line connecting the two arc-shaped portions passing through the aforementioned eccentric center is a line that passes through the eccentric center and connects the points of the arc-shaped portions to each other.

[0042] The length of the aforementioned imaginary line being equal to the specified interval can mean being identical, or it can mean being slightly shorter with a tolerance.

[0043] According to the present invention, a stable and high compression surface pressure can be obtained.

[0044] Specifically, the rotary movement switching mechanism in the butterfly valve, which opens and closes the flow path of the valve housing by rotating the valve body using the valve stem to abut against the seat ring, can cause the valve body to rotate along with the valve stem as it rotates from the valve-open position to a predetermined angle, and can cause the valve body to move in close contact with the seat ring by rotating the valve stem beyond the predetermined angle.

[0045] Additionally, the rotary movement conversion mechanism includes: a cam body disposed on either the valve stem or the valve body; and a cam groove disposed on the other of the valve stem and the valve body. The cam groove is into which the cam body is inserted and has abutting portions spaced at predetermined intervals along the direction of movement. The cam body has at least two arcuate portions centered on an eccentric center, which is eccentric relative to the axis that serves as the rotation center of the valve stem. The two arcuate portions are arranged in opposing orientations, separated by the eccentric center, and the length of the imaginary line connecting the two arcuate portions passing through the eccentric center is set to be equal to the predetermined interval.

[0046] The rotary movement conversion mechanism that constitutes the cam body and the cam groove causes the cam body to rotate relative to the cam groove as the valve stem rotates beyond the predetermined angle. The abutting portion, which is arranged at the predetermined interval in the cam groove, abuts against the two arc-shaped portions, causing the valve body to move from the axis along the flow path in a manner that is in close contact with the seat ring.

[0047] Therefore, in the closed state, the valve body and the seat ring are in close contact under a high compressive surface pressure. Thus, even when cutting off the flow of fluids with small molecular sizes or extremely low temperatures such as cryogenic fluids, the fluid will not flow out between the seat ring and the valve body, reliably cutting off the flow path.

[0048] Furthermore, the abutting portion in the cam groove is arranged at a predetermined interval, and the two arc-shaped portions arranged opposite each other across the eccentric center are configured such that the length of the imaginary line connecting the two arc-shaped portions passing through the eccentric center is equal to the predetermined interval. Therefore, when the cam body rotates relative to the cam groove, no play occurs between the abutting portion arranged at the predetermined interval and the two arc-shaped portions. Therefore, by rotating the valve stem beyond a predetermined angle, the valve body can be moved from the axis along the flow path in a stable state in close contact with the seat ring.

[0049] Alternatively, as an embodiment of the present invention, the two arc-shaped portions may have a large-diameter arc-shaped portion and a small-diameter arc-shaped portion with different diameters. The large-diameter arc-shaped portion and the small-diameter arc-shaped portion are arranged opposite each other with respect to the eccentric center. The length of the imaginary line connecting the large-diameter arc-shaped portion and the small-diameter arc-shaped portion passing through the eccentric center is set to be equal to the predetermined interval. By rotating the valve stem beyond the predetermined angle, the large-diameter arc-shaped portion and the small-diameter arc-shaped portion abut against the abutting portion arranged in the cam groove at the predetermined interval.

[0050] According to the present invention, even if the eccentricity of the eccentric center relative to the axis is varied, the valve body can reliably abut against the abutted part, thereby moving the valve body from the axis along the flow path in a manner that is in close contact with the seat ring.

[0051] Alternatively, as an embodiment of the present invention, when the valve stem has been rotated by the predetermined angle, the eccentric center is eccentric relative to the axis in the opposite direction of movement, the large-diameter arcuate portion is disposed relative to the eccentric center on the side of the movement direction, and the small-diameter arcuate portion is disposed relative to the eccentric center on the side of the opposite direction of movement.

[0052] According to the present invention, even when the eccentric center is eccentric relative to the axis in the opposite direction of movement after rotating by a predetermined angle, the large-diameter arcuate portion disposed relative to the eccentric center on the side of the movement direction and the small-diameter arcuate portion disposed relative to the eccentric center on the side of the opposite movement direction can abut against the abutted portion, causing the valve body to move from the axis along the flow path in a manner that is in close contact with the seat ring. Furthermore, even during reverse rotation, it can abut against the abutted portion, causing the valve body, which is in close contact with the seat ring, to move away along the flow path toward the axis.

[0053] Alternatively, as an embodiment of the present invention, when the valve stem is rotated by the predetermined angle, the eccentric center is eccentric relative to the axis in a direction perpendicular to the direction of movement, the large-diameter arcuate portion is disposed relative to the eccentric center on the opposite side of the opposite direction of movement and opposite to the side on which the eccentric center is disposed, and the small-diameter arcuate portion is disposed relative to the eccentric center on the side of the direction of movement and on the side on which the eccentric center is disposed.

[0054] According to the present invention, even when the eccentric center is eccentric relative to the axis in a direction perpendicular to the direction of movement after rotating by a predetermined angle, the large-diameter arcuate portion disposed on the opposite side of the eccentric center in the opposite direction of movement and the small-diameter arcuate portion disposed on the side of the eccentric center in the direction of movement can abut against the abutted portion, causing the valve body to move from the axis along the flow path in a manner that is in close contact with the seat ring. Furthermore, even during reverse rotation, it can abut against the abutted portion, causing the valve body, which is in close contact with the seat ring, to move away along the flow path toward the axis.

[0055] Alternatively, as an embodiment of the present invention, a rotation limiting mechanism may be provided, which allows the valve body to rotate from the valve stem's open position to the predetermined angle, limits the rotation of the valve body accompanying the valve stem's rotation beyond the predetermined angle, and allows the valve body to move in a direction that is in close contact with the seat ring.

[0056] According to the present invention, it can achieve the same effect as the rotation limiting mechanism described above.

[0057] Alternatively, as an embodiment of the present invention, the abutting portion provided in the cam groove may be formed by a surface extending in a direction perpendicular to the moving direction, and the cam body may be provided with an open valve abutting surface that contacts the abutting portion surface in the open valve state and a closed valve abutting surface that contacts the abutting portion surface in the closed valve state.

[0058] According to the present invention, in the open valve state, the valve opening contact surface of the cam body contacts the contacted portion surface formed by a surface extending in a direction perpendicular to the moving direction, and in the closed valve state, the valve closing contact surface of the cam body contacts the contacted portion surface formed by a surface extending in a direction perpendicular to the moving direction, thus enabling stable maintenance of each state.

[0059] In addition, the valve stem can be prevented from rotating excessively beyond the surface contact state by the valve opening or closing contact surface.

[0060] Alternatively, as an embodiment of the present invention, the rotary movement conversion mechanism and the rotary restriction mechanism may be disposed on opposite sides of the valve body along the axial direction of the axis, and a transmission member may be provided to transmit the rotational force of the valve stem to the rotary movement conversion mechanism and the rotary restriction mechanism disposed on opposite sides of the valve body along the axial direction, on the side on which no rotational force is input from the valve stem.

[0061] According to the present invention, it is possible to achieve the same effect as the aforementioned transmission component.

[0062] Alternatively, as an embodiment of the present invention, a side portion may be provided in a part of the transmission component, which moves closer to the axis in a predetermined direction to suppress the reduction of the flow path area in the open valve state.

[0063] According to the present invention, it is possible to achieve the same effect as the aforementioned edge portion.

[0064] Invention Effects

[0065] According to the present invention, a butterfly valve capable of obtaining a stable and high compression surface pressure can be provided. Attached Figure Description

[0066] Figure 1 This is an explanatory diagram of a butterfly valve.

[0067] Figure 2 This is an explanatory diagram of a butterfly valve.

[0068] Figure 3 This is an explanatory diagram of a butterfly valve.

[0069] Figure 4 This is an explanatory diagram of a butterfly valve.

[0070] Figure 5 This is an explanatory diagram of a butterfly valve.

[0071] Figure 6 This is an explanatory diagram of the opening and closing mechanism.

[0072] Figure 7 This is an explanatory diagram of the rotary-movement conversion mechanism.

[0073] Figure 8 It is an exploded 3D diagram of the main structure.

[0074] Figure 9 It is an exploded 3D diagram of the main structure.

[0075] Figure 10 This is an explanatory diagram of the opening and closing action.

[0076] Figure 11 This is an explanatory diagram of other types of opening and closing mechanisms.

[0077] Figure 12 This is an explanatory diagram of other types of rotary-movement conversion mechanisms.

[0078] Figure 13 This is an illustration of other opening and closing actions.

[0079] Figure 14 This is an illustration of another type of rotary-movement conversion mechanism.

[0080] Figure 15 This is an illustration of another type of opening and closing action. Detailed Implementation

[0081] One embodiment of the present invention will be described with reference to the accompanying drawings.

[0082] Figures 1 to 5 A diagram illustrating butterfly valve 1 is shown. Figure 6 A diagram illustrating the opening and closing mechanism Y is shown. Figure 7 A diagram illustrating the rotary-movement conversion mechanism MD is shown.Figure 8 and Figure 9 An exploded perspective view of the main structure X is shown. Figure 10 A diagram illustrating the opening and closing action of butterfly valve 1 is shown.

[0083] Specifically, Figure 1 (a) shows a schematic perspective view of the front, right side and top of the butterfly valve 1. Figure 1 (b) shows a schematic perspective view of the back, left side and bottom of the butterfly valve 1. Figure 2 (a) shows a front view of butterfly valve 1 in the open position. Figure 2 (b) shows a rear view of butterfly valve 1 in this state. Figure 2 (c) shows a front view of butterfly valve 1 in the closed state. Figure 2 (d) shows a rear view of butterfly valve 1 in this state.

[0084] Figure 3 (a) shows the state of 90-degree rotation. Figure 1 (a) AA line view, Figure 3 (b) shows Figure 3 (a) BB line view.

[0085] Figure 4 (a) shows a schematic perspective view of the front, right, and top surfaces of the main body mechanism X of the butterfly valve 1, indicating the open valve state. Figure 4 (b) shows a schematic perspective view of the front, right, and top surfaces of the main body mechanism X of the butterfly valve 1, indicating the closed state. Figure 4 (c) shows a schematic perspective view of the front, right side and top of the opening and closing mechanism Y of the butterfly valve 1.

[0086] Figure 5 (a) shows a schematic perspective view of the back, left side, and bottom of the main body mechanism X of the butterfly valve 1, indicating the open valve state. Figure 5 (b) shows a schematic perspective view of the back, left side, and bottom of the main body mechanism X of the butterfly valve 1, indicating the closed state. Figure 5 (c) shows a schematic perspective view of the back, left side and bottom of the opening and closing mechanism Y of the butterfly valve 1.

[0087] Figure 6 (a) shows a schematic exploded perspective view of the front, right side and top of the opening and closing mechanism Y. Figure 6 (b) shows a schematic exploded perspective view of the back, left side, and bottom of the opening / closing mechanism Y. Additionally, in Figures 4 to 6The over-rotation prevention bolt 95 is omitted from the illustration.

[0088] Figure 7 (a) shows an enlarged top view of the cam groove 54 disposed in the horizontal portion 53 of the push-in base 51 constituting the rotary movement conversion mechanism MD. Figure 7 (b) shows an enlarged top view of the cam 80 that constitutes the rotary motion conversion mechanism MD.

[0089] Figure 8 A schematic exploded perspective view showing the front, right side, and top surfaces of the main body structure X is shown. Figure 9 A schematic exploded perspective view showing the back, left side, and bottom of the main body X is shown.

[0090] The opening and closing action of butterfly valve 1 will be explained. Figure 10 of Figure 10 (a) shows the valve open state. Figure 3 (b) CC line view, Figure 10 (b) shows the state. Figure 3 (b) DD line view, Figure 10 (c) shows the state. Figure 3 (b) EE line view.

[0091] in addition, Figure 10 (d) shows the 45-degree rotation state, where the valve stem 40 has been rotated 45 degrees clockwise from the open state. Figure 3 (b) CC line view, Figure 10 (e) shows the state. Figure 3 (b) DD line view, Figure 10 (f) shows the state. Figure 3 (b) EE line view.

[0092] and then, Figure 10 (g) shows the 135-degree rotation state, where the valve stem 40 has been rotated 135 degrees clockwise from the open state. Figure 3 (b) CC line view, Figure 10 (h) indicates the state. Figure 3 (b) DD line view, Figure 10 (i) shows the state. Figure 3 (b) EE line view.

[0093] in addition, Figure 10 (j) shows the closed valve state, which is the result of rotating the valve stem 40 180 degrees clockwise from the open valve state. Figure 3 (b) CC line view, Figure 10(k) indicates the state. Figure 3 (b) DD line view, Figure 10 (l) shows the state. Figure 3 (b) EE line view.

[0094] In addition, some of the bolt holes through which the bolts are inserted or tightened, as well as the bolts themselves, are omitted from the above-mentioned figures.

[0095] In addition, Figure 10 In (a), the vertical direction is set as the height direction H, the direction connecting the upper left and lower right is set as the width direction W, and the direction connecting the upper right and lower left is set as the depth direction D.

[0096] Furthermore, the upper side in the height direction H is designated as the upper side (HU), and the lower side is designated as the lower side (HD). Additionally, the upper left side in the width direction W, connecting the upper left and lower right, is designated as the left side (WL), and the lower right side is designated as the right side (WR). The upper right side in the depth direction D, connecting the upper right and lower left, is designated as the inner side (DB), and the lower right side is designated as the near-front side (DF). Furthermore, in both the width direction W and the depth direction D, the direction perpendicular to the height direction H is referred to as the horizontal direction.

[0097] The butterfly valve 1 is connected to the piping or other pipelines (not shown) arranged along the depth direction D. The butterfly valve 1 is a valve device used to allow or cut off the flow of liquids or other fluids flowing through the pipeline and thereby adjust the flow rate. It is also called a so-called center-type butterfly valve.

[0098] The butterfly valve 1 has: a main body mechanism X, which has at least a seat ring 20 and a valve housing 10 having a flow path F along the depth direction D inside; and an opening and closing mechanism Y, which has at least a valve stem 40 rotatably disposed on the valve housing 10 and a valve body 50 that opens and closes the flow path F by rotating the valve stem 40.

[0099] like Figure 3 and Figure 8 As shown, the main body mechanism X has a valve housing 10, a seat ring 20, a pressing ring 31, and a fixing ring 32.

[0100] The valve housing 10 has a cylindrical body portion 11 and a base portion 12, and is formed along the depth direction D with a predetermined length. The cylindrical body portion 11 is formed into a generally cylindrical shape in a lying position, and has a flow path F inside that extends along the depth direction D. The base portion 12 is provided on both sides of the cylindrical body portion 11 in the height direction H.

[0101] like Figure 9 As shown, a mounting part 111 for mounting a seat ring 20 is provided on the front side of the cylindrical body 11, which is formed into a generally cylindrical shape.

[0102] The mounting portion 111 protrudes radially inward from the inner surface of the cylinder body 11 at a position where it enters the inner side DB from the end near the front side DF of the cylinder body 11. It has a plurality of bolt holes (not shown) arranged at predetermined intervals along the circumference for fastening bolts used to secure the retaining ring 32 described later. A flow opening 112 is provided on the radially inward side of the mounting portion 111, which protrudes radially inward from the inner surface of the cylinder body 11.

[0103] The pedestal portion 12 has a predetermined thickness in the height direction H, and when viewed from the height direction H, it is formed into a rectangular shape that is longer in the depth direction D than in the width direction W. The pedestal portion 12 has a through hole 121 in the center that extends through the height direction H and communicates with the flow path F.

[0104] Furthermore, the pedestal portion 12 is disposed on both sides of the cylinder body portion 11 in the height direction H and is integrally formed. As described above, the valve housing 10, which is integrally formed by the cylinder body portion 11 and the pedestal portion 12, is made of metal.

[0105] The seat ring 20 is a sealing component that is installed on the mounting part 111 of the cylinder body 11 and abuts against the valve body 50 of the opening and closing mechanism Y described later to seal the flow opening 112. When viewed from the depth direction D, it is formed into a ring shape.

[0106] The seat ring 20 is mounted on the mounting part 111 and is formed with a suitable cross-sectional shape for sealing against the valve body 50. The seat ring 20 is made of an elastic material with suitable elasticity.

[0107] The pressing ring 31 is a flat ring plate formed with a ring shape that is approximately the same as that of the seat ring 20 when viewed from the depth direction D. The pressing ring 31 is disposed between the fixing ring 32 and the seat ring 20 for fixing the seat ring 20 installed in the mounting part 111 to the mounting part 111.

[0108] In addition, the pressing ring 31 is made of a plate material, such as resin or metal, which has a higher rigidity than the seat ring 20.

[0109] The retaining ring 32 is a fixing component used to fix the seat ring 20 installed on the mounting part 111 to the mounting part 111. It has a plurality of bolt mounting parts 321 arranged at predetermined intervals along the circumference for mounting bolts for fixing to the mounting part 111. In addition, the retaining ring 32 is made of a component with appropriate rigidity, such as resin or metal, which can overcome the tightening force of the bolts.

[0110] By using the seat ring 20, pressing ring 31 and fixing ring 32 configured as described above, the seat ring 20 can be installed and fixed to the mounting part 111 of the cylinder body 11.

[0111] In detail, the seat ring 20 is installed on the mounting portion 111 of the cylinder body 11, and a pressing ring 31 is arranged on the near-front side DF of the seat ring 20. Then, a fixing ring 32 is arranged on the near-front side DF of the pressing ring 31, and a bolt is fastened to the mounting portion 111 of the cylinder body 11 in the bolt mounting portion 321 of the fixing ring 32. This constitutes a main body mechanism X that presses and fixes the seat ring 20, which is arranged between the mounting portion 111 and the fixing ring 32, onto the valve body 10, thereby mounting the seat ring 20.

[0112] The opening and closing mechanism Y, assembled on the main body X to form the butterfly valve 1, includes a valve stem 40 rotatably mounted on the valve housing 10 and a valve body 50 that opens and closes the flow path F by rotating the valve stem 40. It also includes a fixed base 60, a push-in base 51, a guide 70, a cam 80, and a cam link 90. ​​Furthermore, there is one valve body 50, one push-in base 51, and one cam link 90; and two valve stems 40, two fixed bases 60, two guides 70, and two cams 80, arranged symmetrically vertically.

[0113] The valve stem 40 is formed into a generally cylindrical shape with a predetermined length in the height direction H. At its end in the height direction H, a square fitting portion 41 is provided that engages with the fitting hole 81 of the cam 80 and the fitting hole 93 of the cam link 90. ​​This square fitting portion 41 is formed to a predetermined height and appears square when viewed from below. Furthermore, the square fitting portion 41 is formed to be slightly longer in the height direction H than the combined thickness of the cam 80 (described later) and the horizontal arm 91 of the cam link 90.

[0114] In the butterfly valve 1, the valve stem 40A, which has two valve stems 40, protrudes from the upper HU when it is assembled in the valve housing 10, and has an operating part 42 at the upper end for mounting a handle or actuator.

[0115] In contrast, such as Figure 8 As shown in (b), the valve stem 40B, which is disposed on the lower side HD, is opposite to the valve stem 40A in vertical direction. A square fitting part 41 is provided on the upper side HU, and it is formed to be shortened by an amount equivalent to the operating part 42 of the valve stem 40A.

[0116] Regarding the butterfly valve 1 described in this embodiment, the clockwise rotation of the valve stem 40 when viewed from above is the rotation in the valve-closing direction, and the counterclockwise rotation when viewed from above is the rotation in the valve-opening direction.

[0117] The valve body 50 is rotated via the valve stem 40 through the push-in base 51 (described later) to open and close the flow path F. The valve body 50 is formed in a generally disc-shaped manner with a horizontal axis perpendicular to the height direction H as its center.

[0118] In detail, the valve body 50 is a metal disc-shaped structure with a diameter slightly larger than the flow opening 112 of the main cylindrical body 11 of the valve housing 10, and is vertically arranged with its central axis horizontal. Furthermore, in Figure 3 In the orientation shown in (a), the valve body 50 is slightly reduced in diameter toward the front side DF.

[0119] The push-in base 51 is a platform for fixing the valve body 50 and rotating by rotating the valve stem 40. The push-in base 51 is formed into a U-shaped square when viewed from the horizontal direction by a vertical part 52 and a horizontal part 53. The horizontal part 53 is provided on both sides of the vertical part 52 in the height direction H and has a cam groove 54, and is provided with a configuration groove 55 for the guide 70 to be configured.

[0120] In detail, the vertical portion 52 is formed into a rectangular shape with a length in the width direction W that is shorter than the diameter of the valve body 50 and a length in the height direction H that is longer than the diameter of the valve body 50. A mounting portion for mounting the valve body 50 is provided in the center of the vertical portion 52.

[0121] exist Figure 6 In the state shown in (a), the horizontal portion 53 is a rectangular shape viewed from above, slightly longer in the depth direction D than in the width direction W. The horizontal portion 53 has a cam groove 54 and a mounting groove 55. The cam groove 54 and the mounting groove 55 are each formed to be about half the thickness of the horizontal portion 53. When viewed from the horizontal direction, the mounting groove 55 is provided on the outer side of the infeed base 51 in the height direction H, which is formed as an inverted square U-shape, and the cam groove 54 is provided on the inner side in the height direction H.

[0122] Specifically, a mounting groove 55 is provided on the upper surface of the horizontal portion 53 of the upper HU, and a cam groove 54 is provided on the lower surface. Conversely, a cam groove 54 is provided on the upper surface of the horizontal portion 53 of the lower HD, and a mounting groove 55 is provided on the lower surface.

[0123] The cam groove 54 is a groove in which the cam 80 (described later) is internally disposed and engaged by the rotation of the cam 80 in conjunction with the rotation of the valve stem 40. The cam groove 54 is formed with a height approximately the same as the thickness of the cam 80. Furthermore, the shape of the cam groove 54 will be described in detail later along with the description of the shape of the cam 80.

[0124] The mounting groove 55 is formed with a top view shape and depth to allow the base portion 72 of the guide 70 (described later) to fit. Therefore, when the base portion 72 is fitted into the mounting groove 55, the insert base 51 and the guide 70 are rotated and fixed. The fixed base 60 is composed of a plate-shaped base body 61 fixed to the pedestal portion 12 of the valve housing 10 and a cylindrical cylindrical protrusion 62 protruding from the base body 61 in the height direction H.

[0125] Furthermore, the fixing base 60 disposed on the upper HU of the valve housing 10 has a cylindrical protrusion 62 extending from the bottom surface of the base body 61 toward the lower HD, and the fixing base 60 disposed on the lower HD of the valve housing 10 has a cylindrical protrusion 62 extending from the upper surface of the base body 61 toward the upper HU. That is, the fixing base 60 disposed on the upper HU of the valve housing 10 and the fixing base 60 disposed on the lower HD of the valve housing 10 are symmetrically arranged in the vertical direction.

[0126] The base body 61 is formed with a top view shape that is substantially the same as that of the pedestal portion 12 of the valve housing 10, and the base body 61 is configured to be fastened to the pedestal portion 12 by bolts (not shown).

[0127] The cylindrical protrusion 62 is cylindrical in shape and has a diameter that allows it to be inserted through the through hole 121 when the fixing base 60 is positioned on the pedestal portion 12. Figure 6 As shown in (b), the cylindrical protrusion 62 is formed at the height of its front end reaching the flow path F.

[0128] A rotation limiting groove 63 is formed at the front end of the cylindrical protrusion 62. The rotation limiting groove 63 is fitted into the convex portion 71 of the guide 70 (described later) to limit the rotation of the convex portion 71 or allow movement in a specified direction.

[0129] like Figure 3 As shown in (a), (d), (g), and (j), the groove frame 631 constituting the rotation limiting groove 63 has a frame opening 632 on the near-front side DF that allows relative movement of the convex portion 71 towards the near-front side DF, and has an arcuate frame 633 approximately half a circumference in size from the left side WL of the frame opening 632, and a circular side frame 634 on the right side WR with a surface along the depth direction D. Furthermore, an arcuate recess 635, which becomes concave on the right side WR, is provided on the inner surface of the circular side frame 634, allowing the arcuate portion of the convex portion 71 to slide. Additionally, the frame opening 632 is formed with an opening width that is approximately one circumference larger than the length of the convex portion 71 in the short axis direction, as described later.

[0130] The slot frame 631 is surrounded by an arc frame 633 and a round side frame 634 as described above and communicates with the frame opening 632, thereby being configured to allow the convex portion 71 of the guide 70, which will be described later, to fit into the slot.

[0131] The aforementioned rotation limiting groove 63 is formed on the bottom surface of the cylindrical protrusion 62 of the fixing base 60 disposed on the upper side HU of the valve housing 10, and on the upper surface of the cylindrical protrusion 62 of the fixing base 60 disposed on the lower side HD of the valve housing 10.

[0132] Furthermore, a through insertion hole 64 is formed at the center of the cylindrical protrusion 62 in the fixed base 60 when viewed from above. This through insertion hole 64 extends along the height direction H and allows the valve stem 40 to be inserted through it. The through insertion hole 64 is a cylindrical space that is slightly larger than the valve stem 40.

[0133] Additionally, the mounting base 60 located on the lower side HD of the valve housing 10 has a supporting metal device 65 (see reference) to support the valve stem 40B inserted into the through insertion hole 64 to prevent it from falling out. Figure 10 The upper HU fixed base 60 has an anti-disengagement ring 66 to prevent the inserted valve stem 40A from disengaging.

[0134] The guide 70 has a convex portion 71 that is fitted into the rotation limiting groove 63 of the fixed base 60 and a base portion 72 that is fitted into the placement groove 55 of the insert base 51. When viewed from the horizontal direction, the guide 70 is generally convex and has a through hole 73 that extends along the height direction H near the center when viewed from above.

[0135] The convex portion 71 is formed in a generally bag-shaped plan view, which is longer in the depth direction D than in the width direction W. The base portion 72 is formed in a generally rectangular shape in the plan view, which is longer in the depth direction D than in the width direction W. The convex portion 71 and the base portion 72 are made of metal and are integrally formed.

[0136] A through hole 73, located approximately at the center of the guide 70 in plan view and extending along the height direction H, has a width wide enough for the valve stem 40 to be inserted through it. The through hole 73 is formed in a generally bag-shaped form in plan view, with a longer length direction. Therefore, the valve stem 40 inserted through the through hole 73 and the guide 70 can move relative to each other along the long axis.

[0137] Cam 80 is a plate-shaped cam having a fitting hole 81 that fits into the square fitting portion 41 of valve stem 40, such as Figure 3 As shown in (b), (e), (h), and (k), the cam 80 is formed in a roughly bell-shaped form with a rounded bottom when viewed from above.

[0138] Specifically, since the fitting hole 81 is fitted into the square fitting part 41 which is square when viewed from below, it is a square through hole that is slightly larger than the planar shape of the square fitting part 41.

[0139] like Figure 10 As shown in (b), the cam 80, which has a roughly bell-shaped shape when viewed from above, is formed by a semi-circular portion 82 centered on the center of the fitting hole 81, a straight portion 83 extending linearly from the semi-circular portion 82, and an arc-shaped portion 84 that is continuous with the straight portion 83 and located on the opposite side of the semi-circular portion 82, separated by a center. Furthermore, the arc-shaped portion 84 is an arc with a radius larger than that of the semi-circular portion 82.

[0140] In addition, such as Figure 7 As shown in (a), the cam groove 54 for the clearance engagement of the aforementioned cam 80 is similar in shape to the cam 80 in the push-in base 51 that faces the front of the vertical portion 52 toward the near front side DF, and is directed toward the right side WR of the arc-shaped portion 84.

[0141] In detail, half of the depth direction D of the cam groove 54 has the same shape as half of the depth direction D of the cam 80, which faces the arc-shaped portion 84 to the right (WR direction). Half of the depth direction D of the cam groove 54 has a small arc-shaped portion 541 corresponding to the semi-circular portion 82, a straight portion 542 corresponding to the straight portion 83 and extending along the width direction W, and a large arc-shaped portion 543 corresponding to the arc-shaped portion 84. Furthermore, these portions are reversed near the center of the depth direction D in the horizontal portion 53 and connected by the straight portion 544 along the depth direction D to form the cam groove 54.

[0142] In the cam groove 54 formed in this way, the portion formed by the small arc-shaped portion 541, the straight portion 542 and the large arc-shaped portion 543 is, as described above, the same shape as half of the cam 80, and is connected by the straight portion 544 in the depth direction D to form the cam groove 54. Therefore, the cam groove 54 is similar in shape to the cam 80.

[0143] In addition, in the cam groove 54, the large arc-shaped portion 543 is a recess corresponding to the arc-shaped portion 84 of the cam 80. The straight portion 542, which is continuous with the large arc-shaped portion 543, is closer to the center of the cam groove 54 than the other small arc-shaped portion 541, the large arc-shaped portion 543, and the straight portion 544. The large arc-shaped portion 543 becomes the pressing surface that is pressed by the arc-shaped portion 84 of the cam 80.

[0144] The cam link 90 is formed into a square U-shape when viewed from the horizontal direction by a pair of horizontal arms 91 and a vertical connection 92. The pair of horizontal arms 91 are arranged at predetermined intervals along the height direction H and extend parallel to each other in the horizontal direction. The vertical connection 92 is connected to one end of the horizontal arms 91 along the height direction H.

[0145] Furthermore, the horizontal arm 91 is longer than the depth direction D of the horizontal portion 53 that is inserted into the base 51, and a square-shaped fitting hole 93 is provided near the end opposite to the side where the vertical connecting portion 92 is provided, for the square fitting portion 41 of the valve stem 40 to fit into. In addition, near the end of the horizontal arm 91 opposite to the side where the vertical connecting portion 92 is provided, a hook-shaped portion 94 is provided that protrudes horizontally relative to the horizontal arm 91 and in a direction perpendicular to the horizontal arm 91, thereby forming the cam connecting rod 90 into a roughly L-shaped form when viewed from above.

[0146] In addition, an over-rotation prevention bolt 95 is provided near the center of the horizontal arm 91 in the longitudinal direction and the hook portion 94 in the cam link 90 to prevent excessive rotation relative to the press-in base 51.

[0147] Specifically, near the center of the horizontal arm 91 along its length, an over-rotation prevention bolt 95 is provided in a protruding manner on the opposite side from the side protruding from the hook portion 94. Additionally, in the hook portion 94, an over-rotation prevention bolt 95 is provided in a protruding manner on the side opposite to the direction in which the horizontal arm 91 extends.

[0148] Thus, regarding the cam link 90 equipped with the over-rotation prevention bolt 95, when viewed from above, the cam link 90 rotates counterclockwise relative to the insert base 51 by a predetermined angle, the over-rotation prevention bolt 95 provided on the hook-shaped portion 94 abuts against the vertical portion 52, preventing excessive counterclockwise rotation. Conversely, regarding the cam link 90 equipped with the over-rotation prevention bolt 95, when viewed from above, the cam link 90 rotates clockwise relative to the insert base 51 by a predetermined angle, the over-rotation prevention bolt 95 provided on the horizontal arm 91 abuts against the vertical portion 52, preventing excessive clockwise rotation.

[0149] The vertical connecting portions 92, which connect one end of the horizontal arms 91 arranged at predetermined intervals in the height direction H, are formed such that their height in the height direction H is lower than that of the vertical portion 52 of the insert base 51. Therefore, the horizontal portions 53 of the insert base 51, which are formed into a folded square U-shape when viewed from the horizontal direction, can be arranged with cam connecting rods 90, which are also formed into a folded square U-shape when viewed from the horizontal direction, between each other.

[0150] The valve stem 40 (40A, 40B), valve body 50, insert base 51, fixed base 60, guide 70, cam 80 and cam link 90, which constitute the elements as described above, are assembled to form the opening and closing mechanism Y.

[0151] Specifically, the valve body 50 is installed on the vertical portion 52 of the base 51 and integrated into the base.

[0152] A cam link 90 is arranged between the horizontal portions 53 in the height direction H of the press-in base 51, a cam 80 is arranged in the cam groove 54, and a guide 70 is arranged in the arrangement groove 55. That is, the cam link 90, the cam 80 arranged in the cam groove 54, and the guide 70 arranged in the arrangement groove 55 are arranged sequentially along the height direction H between the horizontal portions 53 in the height direction H of the press-in base 51. At this time, the engagement hole 93 of the horizontal arm 91 of the cam link 90 arranged between each other in the horizontal portions 53 is connected with the engagement hole 81 of the cam 80 arranged in the cam groove 54 in a manner with the same orientation along the height direction H. Specifically, relative to the press-in base 51 arranged with the vertical portion 52 facing the front DF, the cam link 90 is arranged with the horizontal arm 91 as the inner DB, and the cam 80 is arranged with the arc-shaped portion 84 as the inner DB and the right side WR facing. In this state, the flow path F arranged in the main body mechanism X.

[0153] Then, the fixing base 60 is installed on the pedestal portion 12 of the valve housing 10, which constitutes the main body mechanism X. Specifically, the fixing base 60 is positioned on the pedestal portion 12 such that the cylindrical protrusion 62 of the fixing base 60 is inserted into the through hole 121 of the pedestal portion 12 in the valve housing 10, and is fixed with bolts (not shown). At this time, as Figure 7 As shown, the protruding part 71 of the guide 70, which is fitted into the configuration slot 55 of the opening and closing mechanism Y pre-configured in the flow path F, is inserted into the rotation restriction slot 63 provided at the end of the cylindrical protrusion 62 of the fixed base 60.

[0154] Then, the valve stem 40 is installed by inserting it through the through insertion hole 64 of the fixed base 60. At this time, regarding the valve stem 40, it is inserted through the through hole 73 of the guide 70, which engages with the configuration slot 55 of the opening / closing mechanism Y disposed in the flow path F. The square fitting part 41 is inserted and fitted into the fitting hole 81 of the cam 80 and the fitting hole 93 of the cam connecting rod 90, which communicate along the height direction H, thereby forming the opening / closing mechanism Y. Then, as described above, the opening / closing mechanism Y is assembled into the main body mechanism X, thereby forming the butterfly valve 1. Furthermore, for the valve stem 40 inserted into the through insertion hole 64 of the fixed base 60, an anti-pull-out ring 66 is installed on the upper HU fixed base 60, and a supporting metal device 65 is installed on the lower HD fixed base 60, thereby preventing accidental pull-out of the valve stem 40.

[0155] In this way, the cam 80 and cam link 90, which are assembled in the square fitting part 41 of the valve stem 40 in the fitting hole 81 and fitting hole 93, are integrated. Therefore, the cam 80 and cam link 90 are integrated via the square fitting part 41 of the valve stem 40.

[0156] In contrast, the valve stem 40, which is inserted through the through hole 73, is rotatable relative to the guide 70, and the through hole 73 is formed into a generally elongated oval shape when viewed from above, so that the valve stem 40 and the guide 70 are in a state where they can move relative to each other within a specified range in the long axis direction but their relative movement in the short axis direction is restricted.

[0157] Furthermore, the guide 70 engages with the mounting slot 55 of the push-in base 51, so that the valve stem 40 can rotate freely relative to the push-in base 51 on which the valve body 50 is mounted, and can move relative to it within a specified range in the long axis direction but its relative movement in the short axis direction is restricted.

[0158] Furthermore, the square fitting portion 41 of the valve stem 40, which is rotatably assembled to the insert base 51, and the cam 80 and cam link 90, which are fitted into the fitting holes 81 and 93, also rotate together with the insert base 51 or relative to the insert base 51 as the valve stem 40 rotates. Specifically, during the rotation of the valve stem 40 up to a predetermined angle, the cam 80 and cam link 90 also rotate together with the insert base 51; during the rotation of the valve stem 40 beyond the predetermined angle, the cam 80 and cam link 90 rotate relative to the insert base 51. Therefore, through the rotation of the valve stem 40 beyond the predetermined angle, the cam 80 rotates relative to the cam groove 54 of the insert base 51.

[0159] Furthermore, by rotating the cam 80 relative to the cam groove 54 of the pressing base 51, the arc-shaped portion 84 of the cam 80, which is longer than the semi-circular portion 82 at a distance from the center of the fitting hole 81, functions as a rotary movement conversion mechanism MD that presses and moves the straight portion 542 in the inner circumferential surface of the cam groove 54. That is, the cam groove 54 of the pressing base 51 and the cam 80 rotate together with the valve stem 40 during the rotation of the valve stem 40 up to a predetermined angle, and the rotation of the valve stem 40 beyond the predetermined angle acts in the direction that moves the pressing base 51, thereby enabling it to function as a rotary movement conversion mechanism MD in the butterfly valve 1.

[0160] Furthermore, in the opening and closing mechanism Y, as described above, the convex portion 71 of the guide 70 of the base portion 72 is embedded in the configuration groove 55 of the base 51 and the rotation restriction groove 63 at the front end of the cylindrical protrusion 62 of the fixed base 60 is embedded in the configuration groove 55 of the base 51.

[0161] Specifically, a convex portion 71, which is roughly bag-shaped when viewed from above, is embedded between the arc frame 633 and the circular side frame 634 in the slot frame 631.

[0162] Furthermore, as the valve stem 40 rotates, as described above, the insert base 51 rotates along with the valve stem 40 up to a predetermined angle. At this time, the guide 70, into which the base portion 72 is embedded in the mounting groove 55 of the insert base 51, also rotates along with the valve stem 40, and the roughly bag-shaped convex portion 71, viewed from above, also rotates between the arc frame 633 and the round side frame 634.

[0163] Furthermore, when the valve stem 40 is about to rotate beyond a predetermined angle, the side of the convex portion 71, which has been rotating with the valve stem 40 up to this point, abuts against the side of the circular side frame 634, thus restricting further rotation. However, in the rotation limiting groove 63, a frame opening 632, which is formed with an opening width that is larger than the length of the convex portion 71 in the short axis direction, is provided near the front side DF. Therefore, the convex portion 71 functions as a rotation limiting mechanism MR in the rotation limiting groove 63, allowing it to move towards the front side DF through the frame opening 632.

[0164] Thus, the convex portion 71 and the rotation limiting groove 63 into which the convex portion 71 is inserted function as a rotation limiting mechanism MR that restricts rotation accompanying the rotation of the valve stem 40 up to a predetermined angle, but allows movement towards the forward side DF during rotation of the valve stem 40 beyond the predetermined angle. Furthermore, the rotation limiting mechanism MR also functions as a movement direction limiting unit that restricts the movement direction of the convex portion 71, i.e., the movement direction of the valve body 50.

[0165] The rotary movement conversion mechanism MD and the rotary restriction mechanism MR, thus configured, are positioned on both sides of the valve body 50 in the height direction H.

[0166] Next, refer to Figure 3 The operation of a butterfly valve 1, which is assembled with a main body mechanism X and an opening and closing mechanism Y and has a rotational movement conversion mechanism MD and a rotational limiting mechanism MR, will be explained.

[0167] in addition, Figure 10 Images (a) through (c) show the valve open state with the valve stem 40 rotated counterclockwise to its maximum extent. Figure 10 (d) to (f) show the state where the valve stem 40 has been rotated 45 degrees clockwise from the open state. Figure 10 (g) to (i) show the state where the valve stem 40 has been rotated 135 degrees clockwise from the open state. Figure 10 (j) to (l) show the state in which the valve stem 40 has been rotated 180 degrees clockwise from the open state, and the closed state in which the valve stem 40 has been rotated clockwise to the maximum extent.

[0168] That is, the butterfly valve 1 can switch from the open state, in which the valve stem 40 rotates counterclockwise to the closed state, in which the valve stem 40 rotates clockwise to the maximum extent, by rotating 180 degrees.

[0169] in addition, Figure 10 The (a), (d), (g), and (j) are shown Figure 10 The CC-direction view of (b) illustrates the state in which the convex portion 71 of the guide 70 is embedded in the rotation limiting groove 63 at the front end of the cylindrical protrusion 62 of the fixed base 60, i.e., the state of the rotation limiting mechanism MR.

[0170] in addition, Figure 3 The (b), (e), (h), and (k) diagrams are shown. Figure 10 The DD line view of (b) shows the state in which the cam 80 is embedded in the cam groove 54 of the horizontal part 53 of the press base 51, that is, the state of the rotary movement conversion mechanism MD.

[0171] and then, Figure 3 The (c), (f), (i), and (l) are shown Figure 10 (b) shows the state of valve body 50 in flow path F in the EE line view.

[0172] In addition, Figure 3 In the diagram, left and right represent the width direction W, left side represents left WL, and right side represents right WR. Additionally, in... Figure 10 In the middle, the vertical direction represents the depth direction D, the downward direction represents the near-front side DF, and the upward direction represents the inner side DB.

[0173] Will Figure 10 Taking the valve-opening states shown in (a) to (c) as the initial state, the following will be... Figure 10 The operation of the butterfly valve 1 shown in (j) to (l) from the open state to the closed state will be described in detail, specifically the operation of the rotary movement conversion mechanism MD, the rotary restriction mechanism MR, and the valve body 50 from the open state to the closed state.

[0174] In this specification, in the initial open valve state, such as Figure 10 of (a) Figure 2 (b) Figure 2 of (a) Figure 4 (a) and Figure 5As shown in (c), the valve body 50, mounted on the vertical portion 52 of the insert base 51, is arranged in the flow path F of the valve housing 10 facing to the right WR. Furthermore, the insert base 51 and the cam link 90 are arranged opposite each other along the width direction W, with the vertical portion 52 of the insert base 51 and the vertical connecting portion 92 of the cam link 90 facing each other. Therefore, a generally quadrilateral frame with an opening in the depth direction D is formed by the vertical portion 52 and the upper and lower horizontal portions 53 of the insert base 51, and the vertical connecting portion 92 and the upper and lower horizontal arms 91 of the cam link 90. ​​Thus, in the butterfly valve 1, fluid through the flow path F can flow through the flow opening 112.

[0175] At this time, in the rotation limiting mechanism MR, in the rotation limiting groove 63, the generally bag-shaped convex portion 71 is arranged with its long axis direction along the width direction W.

[0176] Furthermore, in the rotary movement conversion mechanism MD, the vertical portion 52 of the base 51 is positioned as the right side WR. That is, the horizontal portion 53 with the cam groove 54 faces the width direction W, and the cam 80 is positioned inside the cam groove 54 with the arc-shaped portion 84 facing the left side WL and the inner side DB.

[0177] In this state, rotation is not restricted by the rotation limiting mechanism MR. Therefore, when the valve stem 40 is rotated clockwise by a specified angle, i.e., 45 degrees, from the open state, the cam 80 and cam link 90 rotate clockwise by 45 degrees along with the clockwise rotation of the valve stem 40 (see reference). Figure 10 (e)). However, even if the valve stem 40 rotates, the insert base 51, in which the base portion 72 is fitted in the configuration slot 55, does not rotate (see reference). Figure 10 (d)

[0178] With the further clockwise rotation of the convex portion 71 restricted by the rotation limiting mechanism MR as described above, when the valve stem 40 is further rotated to the position of 135 degrees, the cam 80 and the cam connecting rod 90 rotate to the position of 135 degrees (see reference). Figure 10 (i)). Moreover, as the cam 80 and cam link 90 rotate, the push-in base 51 on which the valve body 50 is mounted and the guide 70 also rotate clockwise to a position of 135 degrees (see reference). Figure 10 (d) Therefore, the valve body 50 installed on the vertical part 52 of the insert base 51 is in a position facing the front side DF, but there is a gap between it and the seat ring 20 installed on the mounting part 111, and it is not in a sealed state (see reference). Figure 10 (f)

[0179] Additionally, in this state, such as Figure 10As shown in (d), the convex portion 71, which is roughly bag-shaped when viewed from above, is positioned with its long axis pointing towards the depth direction D in the rotation limiting groove 63, and its side abuts against the side of the circular side frame 634. Therefore, the convex portion 71, whose side abuts against the side of the circular side frame 634, is in a state where further rotation is restricted in the rotation limiting groove 63, but a frame opening 632 is provided on the near-front side DF of the convex portion 71, which is oriented along the depth direction D in the long axis direction, so that movement of the near-front side DF of the convex portion 71 is allowed. That is, when the valve stem 40 is rotated clockwise to a position of 135 degrees from the initial state, the rotation limiting mechanism MR is in a state where further rotation of the convex portion 71 is restricted, but movement of the convex portion 71 towards the near-front side DF is allowed. Therefore, in the cam groove 54, the cam 80 rotates relative to the inner surface of the cam groove 54 by an amount of 90 degrees until the front end of the arc-shaped portion 84 in the rotation direction abuts against the inner surface of the cam groove 54 (see reference). Figure 10 (h)

[0180] In this state, when the valve stem 40 is further rotated to a 180-degree position, the cam 80 and the cam connecting rod 90 rotate to a 180-degree position (see reference). Figure 10 (l)). However, further clockwise rotation of the convex portion 71 is limited by the rotation limiting groove 63 constituting the rotation limiting mechanism MR, so even if the valve stem 40 rotates, the insert base 51, in which the base portion 72 is fitted in the mounting groove 55, does not rotate (see reference). Figure 10 (j) Therefore, in the cam groove 54, the cam 80 rotates relative to the straight portion 542, which is the inner surface of the cam groove 54, by pressing the arc-shaped portion 84 toward the near-front side DF. Figure 10 (h) Therefore, the straight portion 542 of the cam groove 54 is pressed into the front side DF by the arc-shaped portion 84, and the push-in base 51 moves towards the front side DF. At this time, the through hole 73 of the guide 70 is oriented along the depth direction D in the long axis direction, and the convex portion 71 moves relative to the valve stem 40 towards the front side DF through the frame opening 632 of the rotation limiting groove 63 (refer to...). Figure 10 (j)).

[0181] Thus, by further rotating the valve stem 40, the arc-shaped portion 84 of the cam 80, which functions as the rotary movement conversion mechanism MD, presses the straight portion 542 of the cam groove 54 toward the forward side DF. As a result, the push-in base 51 on which the valve body 50 is mounted moves toward the forward side DF, and the valve body 50 comes into close contact with the seat ring 20 mounted on the mounting portion 111, thereby sealing the flow opening 112.

[0182] Additionally, at this time, the over-rotation prevention bolt 95 of the horizontal arm 91 mounted on the cam link 90 abuts against the vertical part 52, limiting further clockwise relative rotation of the cam link 90 relative to the pressed base 51.

[0183] Thus, the valve stem 40 can be rotated clockwise to a 180-degree position from the initial open state to become the closed state, but when the valve stem 40 is rotated counterclockwise to a 180-degree position from the closed state, it can become the open state.

[0184] Specifically, when the valve stem 40 is rotated counterclockwise to a position of 45 degrees, the cam 80 and cam link 90 rotate counterclockwise by 45 degrees along with the rotation of the valve stem 40. However, even when the valve stem 40 rotates, the push-in base 51, in which the base portion 72 is fitted in the mounting groove 55, does not rotate.

[0185] In this state, when the valve stem 40 is further rotated counterclockwise to a position of 90 degrees, the cam 80 and the cam connecting rod 90 also rotate counterclockwise to a position of 90 degrees. Therefore, in the cam groove 54, a relative rotation of 45 degrees counterclockwise is made, causing the base 51 to move inward to DB, that is, pulling the valve body 50 inward to DB, thus releasing the tight contact between the valve body 50 and the seat ring 20.

[0186] Then, as the valve stem 40 is further rotated counterclockwise to a position of 180 degrees, i.e., the valve-opening position, the cam 80 and cam link 90 also rotate counterclockwise to a position of 180 degrees, i.e., the valve-opening position, along with the rotation of the cam 80 and cam link 90. ​​Moreover, as the cam 80 and cam link 90 rotate, the push-in base 51 and guide 70, on which the valve body 50 is mounted, also rotate counterclockwise to a position of 180 degrees, i.e., the valve-opening position, thus achieving the valve-opening state.

[0187] As described above, the butterfly valve 1 includes: a valve housing 10 having a tubular flow path F; a valve stem 40 rotatably disposed on the valve housing 10; a valve body 50 that rotates via the valve stem 40 to open and close the flow path F; and a seat ring 20 disposed between the valve housing 10 and the valve body 50. Furthermore, a rotational movement switching mechanism MD is provided between the valve stem 40 and the valve body 50. This mechanism rotates the valve body 50 as the valve stem 40 rotates from the open position to a 90-degree position, and moves the valve body 50 in close contact with the seat ring 20 by rotating the valve stem 40 clockwise by more than 135 degrees.

[0188] The rotary movement conversion mechanism MD has: a cam 80 having an arcuate portion 84 in the circumferential direction with a diameter longer than the other portion, the cam 80 being disposed on the valve stem 40; and a cam groove 54 for the cam 80 to be inserted into, the cam groove 54 being disposed on the valve body 50.

[0189] The cam groove 54 is provided with a large arc-shaped portion 543 corresponding to the arc-shaped portion 84 and a straight portion 542 that is continuous with the large arc-shaped portion 543 and pressed into the arc-shaped portion 84. Moreover, in the rotary movement conversion mechanism MD, by rotating the valve stem 40 by more than 135 degrees, the arc-shaped portion 84 disengages from the large arc-shaped portion 543 and is pressed into the straight portion 542, thereby causing the valve body 50 to move from the axis along the flow path F in a manner that is in close contact with the seat ring 20. Therefore, even for high-pressure fluids, a stable and high compressible surface pressure can be obtained in the closed valve state, and the flow path F can be reliably cut off.

[0190] Specifically, the rotary movement conversion mechanism MD in the butterfly valve 1, which opens and closes the flow path F of the valve housing 10 by rotating the valve body 50 using the valve stem 40 to abut against the seat ring 20, can rotate the valve body 50 along with the valve stem 40 from the open position to the 135-degree position. Furthermore, by rotating the valve stem 40 clockwise by more than 135 degrees, the valve body 50 moves from the axis along the flow path F in a manner that is in close contact with the seat ring 20.

[0191] Additionally, the rotary movement conversion mechanism MD includes: a cam 80 having an arcuate portion 84 in which a portion of the diameter is longer than the other portion in the circumferential direction, the cam 80 being disposed on the valve stem 40; and a cam groove 54 into which the cam 80 is inserted, the cam groove 54 being disposed on the valve body 50, the cam groove 54 having a large arcuate portion 543 corresponding to the arcuate portion 84 and a straight portion 542 continuous with the large arcuate portion 543 and pressed into the arcuate portion 84. Therefore, by rotating the valve stem 40 by more than 135 degrees, the arcuate portion 84 disengages from the large arcuate portion 543 and is pressed into the straight portion 542, thereby causing the valve body 50 to move from the axis along the flow path F in a manner that is in close contact with the seat ring 20.

[0192] Therefore, in the closed state, the valve body 50 and the seat ring 20 are in close contact under a high compression surface pressure. Furthermore, since the transition to the closed state, where the valve body 50 and seat ring 20 are in close contact under a high compression surface pressure, reduces the operating torque of the valve stem 40, improving operability. Thus, because the valve body 50 and seat ring 20 are in close contact under a high compression surface pressure with a smaller operating torque, it goes without saying that the flow of fluids with small molecular sizes, extremely low-temperature fluids such as cryogenic fluids, towards the forward side DF is acceptable. Even when the flow towards the inward side DB, which exerts pressure on the valve body 50 in the opening direction, is cut off, the flow path F can be reliably cut off, preventing fluid from flowing out between the seat ring 20 and the valve body 50.

[0193] Furthermore, the valve body 50 is allowed to rotate from the open position of the valve stem 40 to a 90-degree position, the rotation of the valve body 50 along with the clockwise rotation of the valve stem 40 exceeding 90 degrees is restricted, and movement of the valve body 50 near its forward side DF is allowed. That is, a rotation limiting mechanism MR is provided, which also functions as a movement direction limiting mechanism.

[0194] Therefore, by means of the rotation limiting mechanism MR, the rotation of the valve body 50, which is associated with the clockwise rotation of the valve stem 40 by more than 135 degrees, is limited. And in the closed state, by means of the rotation movement switching mechanism MD, the valve body 50 is moved to the forward side DF, which can reliably cut off the flow path F.

[0195] In addition, the rotary movement conversion mechanism MD and the rotary restriction mechanism MR are disposed on both sides of the valve body 50 in the height direction H. The rotary movement conversion mechanism MD and the rotary restriction mechanism MR on the lower side HD of the rotary movement conversion mechanism MD and the rotary restriction mechanism MR disposed on both sides of the valve body 50 in the height direction H are provided with a cam connecting rod 90 for transmitting the rotational force of the valve stem 40.

[0196] Therefore, via the cam link 90, the rotational force of the valve stem 40 can be transmitted to the lower side HD of the rotational movement conversion mechanism MD and the rotational limiting mechanism MR, which are located on both sides of the valve body 50 in the height direction H. Thus, by using the rotational movement conversion mechanism MD and the rotational limiting mechanism MR located on both sides of the height direction H, the rotation of the valve body 50, which accompanies a clockwise rotation of the valve stem 40 exceeding 90 degrees, is restricted. Simultaneously, in the closed state, the rotational movement conversion mechanism MD moves the valve body 50 towards the forward side DF, enabling more reliable shut-off of the flow path F.

[0197] In addition, the cam link 90 is provided with a horizontal arm 91 and a vertical connecting part 92 that move from the axis toward a specified direction to suppress the reduction of the area of ​​the flow path F in the open valve state. Therefore, the flowability in the open valve state is not reduced, and in the closed valve state, the valve body 50 is moved toward the front side DF by the rotary movement conversion mechanism MD, which can more reliably cut off the flow path F.

[0198] Specifically, the axis of rotation of the rotating valve stem 40 and valve body 50 is located at a position that traverses the tubular flow path F cut off by the valve body 50 when it is in the closed position. Therefore, in the lower HD of the rotational movement conversion mechanism MD and rotational restriction mechanism MR, which are provided on both sides of the valve body 50 in the height direction H, when the rotational transmission component that transmits the rotational force of the valve stem 40 is arranged at the axis, it will traverse the flow path F, and in the open state, it will reduce the area of ​​the flow path F and reduce the flowability in the open state.

[0199] In contrast, the cam link 90 is provided with a horizontal arm 91 and a vertical connecting portion 92 that move in a predetermined direction from the axis, thus suppressing the reduction of the flow path F area in the open valve state. This suppresses the decrease in flowability caused by the cam link 90 in the open valve state, while in the closed valve state, the valve body 50 is moved towards the forward side DF by the rotary shifting mechanism MD, enabling more reliable shut-off of the flow path F.

[0200] Furthermore, since an over-rotation prevention bolt 95 is provided to limit excessive rotation of the valve stem 40, further rotation of the valve stem 40 from the closed and open positions can be prevented. Therefore, loads acting on the valve stem 40, valve body 50, or seat ring 20 due to excessive rotation of the valve stem 40 can be prevented.

[0201] Furthermore, in the butterfly valve 1 in the closed state, when the valve stem 40 is rotated counterclockwise to a position of 90 degrees, the base 51 is pressed inward and moved to DB. The tight contact between the valve body 50 and the seat ring 20 is released, thus reducing the torque required to operate the valve stem 40 when transitioning from the closed state to the open state and improving operability.

[0202] Next, other embodiments of the present invention will be described with reference to the accompanying drawings.

[0203] Figure 10 An explanatory diagram of the opening and closing mechanism Ys according to other embodiments is shown. Figure 11 Explanatory diagrams of rotary motion conversion mechanisms (MDs) according to other embodiments are shown. Figure 12 An explanatory diagram showing the opening and closing operation of the butterfly valve 1 in another embodiment is provided.

[0204] Specifically, Figure 13 (a) and (b) show the relationship with Figure 11 The corresponding diagrams for (a) and (b).

[0205] Figure 6 (a) shows an enlarged top view of the cam groove 54s of the horizontal portion 53s of the push-in base 51s provided in the rotary movement conversion mechanism MDs constituting another embodiment. Figure 12 (b) shows an enlarged top view of the cam 80s that constitutes the rotary motion conversion mechanism MDs. Figure 12 (c) shows an enlarged top view of the state in which the cam 80s is embedded in the cam groove 54s in the open valve state.

[0206] In addition, Figure 12 In the diagram, the cam groove 54s, cam 80s, and rotary movement conversion mechanism MDs are shown in the orientation in which the valve stem 40 is rotated by a specified angle (90 degrees) from the open valve state.

[0207] Figure 12Figures (a) to (c) show the butterfly valve 1 with its opening and closing mechanism Ys in the open state. Figure 13 The diagrams corresponding to (a) to (c) Figure 10 (d) to (f) show the state of the valve stem 40 rotating 90 degrees clockwise from the open state to the 90-degree rotation state. Figure 13 The diagrams corresponding to (d) to (f).

[0208] and then, Figure 10 (g) to (i) show the state of rotation of valve stem 40 by 135 degrees clockwise from the open state. Figure 13 The graphs corresponding to (g) to (i) Figure 10 (j) to (l) show the relationship between the valve stem 40 rotated 180 degrees clockwise from the open valve state and the closed valve state. Figure 13 The graph corresponding to (j) to (l).

[0209] Furthermore, in the above figures, in the butterfly valve 1 with the opening and closing mechanism Ys, those with the same structure as the butterfly valve 1 with the opening and closing mechanism Y are marked with the same reference numerals and their descriptions are omitted.

[0210] The butterfly valve 1 with opening and closing mechanism Ys is the same as the butterfly valve 1 with opening and closing mechanism Y. It is a valve device that is connected to a pipeline (not shown) arranged along the depth direction D and is used to allow or cut off the flow of fluids such as liquids flowing through the pipeline and thereby adjust the flow rate. It is also called a so-called center-type butterfly valve.

[0211] In the butterfly valve 1 with opening and closing mechanism Ys, the cam 80s in the opening and closing mechanism Ys and the cam groove 54s provided in the horizontal part 53s of the pressing base 51s are different from the cam 80 and cam groove 54s in the opening and closing mechanism Y of the butterfly valve 1. The other structures in the main body mechanism X and the opening and closing mechanism Ys are the same as those in the main body mechanism X and the opening and closing mechanism Y of the butterfly valve 1. Therefore, the structure of the cam 80s and the cam groove 54s and the operation of the opening and closing mechanism Ys with the cam 80s and the cam groove 54s will be explained below.

[0212] Similar to the push-in base 51 of the opening and closing mechanism Y, the push-in base 51s is a platform for fixing the valve body 50 and rotating it by rotating the valve stem 40. The push-in base 51s is formed into a square U-shape when viewed from the horizontal direction by a vertical part 52 and a horizontal part 53s. The horizontal part 53s is provided on both sides of the vertical part 52 in the height direction H and has a cam groove 54s and a mounting groove 55 for mounting the guide 70.

[0213] In detail, Figure 10In the state shown in (a), the horizontal portion 53s is a rectangular shape viewed from above, slightly longer in the depth direction D than in the width direction W. The horizontal portion 53s has a cam groove 54s and a placement groove 55. The cam groove 54s and the placement groove 55 are each formed to be about half the thickness of the horizontal portion 53s. When viewed from the horizontal direction, the placement groove 55 is provided on the outer side of the indentation base 51s in the height direction H, which is formed as an inverted square U-shape, and the cam groove 54s is provided on the inner side in the height direction H.

[0214] Similar to the cam groove 54, the cam groove 54s is a groove in which the cam 80s (described later) is disposed internally and is locked or pressed in by the rotation of the cam 80s in conjunction with the rotation of the valve stem 40. The cam groove 54s is formed with a height approximately the same as the thickness of the cam 80s.

[0215] The cam groove 54s is a large, roughly rectangular space in plan view, with a length in the width direction W slightly longer than the length in the depth direction D, i.e., the depth length DL. In this embodiment, the cam groove 54s is formed with a length of about half the length in the depth direction D of the horizontal portion 53s, and with a length of about 2 / 3 the length in the width direction W of the horizontal portion 53s.

[0216] The cam groove 54s thus formed is configured to be offset to the right by WR relative to the center of the width direction W of the horizontal portion 53s, and to be offset inward by DB relative to the center of the depth direction D of the horizontal portion 53s. Furthermore, compared to the offset in the depth direction D of the cam groove 54s, which is offset inward by DB relative to the center of the depth direction D of the horizontal portion 53s, the offset in the width direction W of the cam groove 54s, which is offset to the right by WR relative to the center of the width direction W of the horizontal portion 53s, is set to be larger.

[0217] In addition, the inner surfaces on both sides of the depth direction D in the cam groove 54s formed in this way are designated as the contact surfaces 541s, the inner surface of the near front side DF in the contact surfaces 541s is designated as the near front inner surface 542s, and the inner surface of the inner side DB is designated as the inner inner surface 543s.

[0218] Cam 80s is a plate-shaped cam having a fitting hole 81 that fits into the square fitting portion 41 of valve stem 40, such as Figure 11 As shown in (b), the cam 80 is formed in a different top view shape than the cam 80 which is formed in a roughly bell-shaped form with an arc-shaped bottom.

[0219] In addition, the center of the fitting hole 81 becomes the first center Fc, which coincides with the center of the fitted square fitting part 41, i.e., the axis.

[0220] Specifically, in Figure 12In the valve-open state shown in (b), regarding the top view of the cam 80s, the first straight section 82s, the first arc-shaped section 83s, the second straight section 84s, the second arc-shaped section 85s, the third arc-shaped section 86s, the third straight section 87s, and the fourth arc-shaped section 88s are arranged sequentially from the inside DB in a clockwise direction.

[0221] exist Figure 12 In the open valve state shown in (b), the first straight section 82s is a straight line with the first center Fc, which is the center of the fitting hole 81, pointing to the right WR at the innermost DB.

[0222] The first arc-shaped portion 83s continues from the right end of the first straight portion 82s extending along the width direction W, and is formed as an arc convex towards the right side WR with the first center Fc as the center and the inner side DB being convex. Furthermore, the radius of the first arc-shaped portion 83s is set as the first radius R1. In this embodiment, the first arc-shaped portion 83s is formed as an arc at approximately 45 degrees centered on the first center Fc.

[0223] The second straight section 84s is continuous from the right side WR and near the front side DF end of the first arc-shaped section 83s, forming a straight line along the near front side DF.

[0224] The second arc-shaped portion 85s continues from the end of the second straight portion 84s near the front side DF along the depth direction D, and is formed as a semi-circle convex to the right side WR with the second center Sc eccentric to the first center Fc as the center. In addition, the radius of the second arc-shaped portion 85s is set as the second radius R2.

[0225] Furthermore, the second center Sc, which is the center of the second arc-shaped portion 85s, is positioned off-center from the center of the fitting hole 81, i.e., the first center Fc, by a predetermined interval Z towards the inward side DB. Moreover, the predetermined interval Z of the second center Sc's off-center position relative to the first center Fc towards the inward side DB is the same interval as the amount of movement by which the valve body 50 moves towards the near-forward side DF via the opening and closing mechanism Ys, described later.

[0226] The third arc-shaped portion 86s continues from the left side WL and near the front side DF of the second arc-shaped portion 85s, and is positioned opposite the first arc-shaped portion 83s relative to the first center Fc, forming a semi-circle that is convex towards the left side WL and near the front side DF. Furthermore, the third arc-shaped portion 86s is centered on the first center Fc, and its radius is set as the third radius R3.

[0227] The third straight section 87s is continuous from the end of the left side WL and the inner side DB of the third arc-shaped section 86s, and is formed as a straight line along the inner side DB.

[0228] The fourth arc-shaped portion 88s connects the inner end DB of the third straight portion 87s extending along the depth direction D to the left end WL of the first straight portion 82s extending along the width direction W. The fourth arc-shaped portion 88s is positioned opposite the second arc-shaped portion 85s to the second center Sc, forming a semi-circle facing the left WL with its inner end DB convex. Furthermore, the fourth arc-shaped portion 88s is centered on the second center Sc, and its radius is set as the fourth radius R4.

[0229] That is, the first arc-shaped portion 83s formed with the first radius R1 and the third arc-shaped portion 86s formed with the third radius R3 are arc-shaped with the first center Fc as the center, and are configured to be convex on the opposite side of the first center Fc with opposite orientations. In addition, the first radius R1 of the first arc-shaped portion 83s, which is located on the inner side DB of the second center Sc relative to the first center Fc, is set to be larger than the third radius R3 of the third arc-shaped portion 86s, which is located on the near front side DF relative to the first center Fc.

[0230] Furthermore, the second arc-shaped portion 85s formed with the second radius R2 and the fourth arc-shaped portion 88s formed with the fourth radius R4 are arc-shaped with the second center Sc as the center, and are configured to be convex on the opposite side relative to the second center Sc, with their orientations reversed. In addition, the second radius R2 of the second arc-shaped portion 85s, which is disposed near the front side DF relative to the second center Sc, is set to be larger than the fourth radius R4 of the fourth arc-shaped portion 88s, which is disposed on the inner side DB of the second center Sc relative to the first center Fc.

[0231] Furthermore, the radii (R3, R4) of the third arc-shaped portion 86s, which is located to the left of the first center Fc and centered on the first center Fc, and the fourth arc-shaped portion 88s, which is centered on the second center Sc, are set to the same length.

[0232] In addition, the first radius R1 of the first arc-shaped portion 83s centered on the first center Fc is set to be longer than the second radius R2 of the second arc-shaped portion 85s centered on the second center Sc, and the second radius R2 of the second arc-shaped portion 85s is set to be longer than the radii (R3, R4) of the third arc-shaped portion 86s and the fourth arc-shaped portion 88s.

[0233] Therefore, the interval between the boundary between the second arc-shaped portion 85s and the third arc-shaped portion 86s, centered at the second center Sc, and the first center Fc, becomes the third radius R3 of the third arc-shaped portion 86s. The interval between the boundary between the second arc-shaped portion 85s and the third arc-shaped portion 86s, and the second center Sc, becomes the second radius R2 of the second arc-shaped portion 85s, and is a length shorter than the first radius R1 of the first arc-shaped portion 83s. Therefore, in the second arc-shaped portion 85s, the distance from the first center Fc gradually increases from the boundary with the third arc-shaped portion 86s toward the boundary with the second arc-shaped portion 85s.

[0234] The distance between the boundary of the fourth arc-shaped portion 88s centered on the second center Sc and the first straight portion 82s and the first center Fc is longer than the fourth radius R4. Specifically, it is set to be the sum of the eccentricity of the second center Sc relative to the first center Fc and the length of the fourth radius R4. Furthermore, the distance between the boundary of the fourth arc-shaped portion 88s and the third straight portion 87s and the first center Fc is longer than the fourth radius R4, becoming a length shorter than the sum of the eccentricity of the second center Sc and the length of the fourth radius R4. Therefore, in the fourth arc-shaped portion 88s, the distance from the first center Fc gradually decreases from the boundary with the first straight portion 82s towards the boundary with the third straight portion 87s.

[0235] Furthermore, the length of the imaginary line VL, which passes through the second center Sc and connects any point on the second arc-shaped portion 85s with any point on the fourth arc-shaped portion 88s, is always set to be constant. Additionally, the length of the imaginary line VL, which passes through the second center Sc and connects any point on the second arc-shaped portion 85s with any point on the fourth arc-shaped portion 88s, is set to be equal to the depth length DL of the cam groove 54s.

[0236] Furthermore, the lengths of the first straight section 82s along the width direction W, the third straight section 87s along the depth direction D, and the second straight section 84s along the depth direction D are set to become progressively shorter.

[0237] In addition, the length of the third straight section 87s along the depth direction D is formed at a predetermined interval Z with the second center Sc being eccentric relative to the first center Fc, that is, with a length corresponding to the amount of movement of the valve body 50 towards the near front side DF through the opening and closing mechanism Ys.

[0238] The opening and closing mechanism Ys, which includes the push-in base 51s and the cam 80s having the cam groove 54s configured as described above, can be assembled in the same manner as the assembly method of the opening and closing mechanism Y described above.

[0239] In addition, the opening and closing mechanism Ys, which includes the push-in base 51s with cam groove 54s and cam 80s, is configured with cam 80s in the cam groove 54s, which is formed into a roughly rectangular shape in plan view that is larger in width direction than depth direction D. The first straight portion 82s is the inner side DB, the second straight portion 84s is the right side WR, and the third straight portion 87s is the left side WL.

[0240] At this time, the boundary portion of the second arc-shaped portion 85s and the third arc-shaped portion 86s in the cam 80s abuts against the near-inner side surface 542s of the cam groove 54s, which is formed to have a larger width direction W than the depth direction D when viewed from above, and the first straight portion 82s abuts against the inner side surface 543s of the inner side DB of the cam groove 54s.

[0241] In addition, the third straight section 87s abuts against the inner side of the left WL of the cam groove 54s.

[0242] Furthermore, when viewed from above, the first straight section 82s and the third straight section 87s, which are formed as straight lines, are in a state of being opposed to and abutting the contact surface 541s (542s, 543s) of the cam groove 54s in the depth direction D, i.e., surface contact.

[0243] In addition, the contact between a portion of the cam 80s and the contact surface 541s of the cam groove 54s can be an actual contact or a gap of a certain tolerance.

[0244] The butterfly valve 1, which is formed by assembling the opening and closing mechanism Ys onto the main body mechanism X, performs the same function as the butterfly valve 1 with the aforementioned opening and closing mechanism Ys.

[0245] Next, with Figure 12 The operation of the butterfly valve 1, which assembles the main body mechanism X and the opening / closing mechanism Ys to form the opening / closing mechanism Ys including the rotary movement conversion mechanism MDs and the rotary limiting mechanism MR, will be explained together. Furthermore, in Figure 13 In, with Figure 13 The diagrams are drawn in the same direction.

[0246] in addition, Figure 10 Images (a) through (c) show the valve open state with the valve stem 40 rotated counterclockwise to its maximum extent. Figure 13 Figures (d) to (f) show the state in which the valve stem 40 has been rotated 90 degrees clockwise from the open position. Figure 13 (g) to (i) show the state where the valve stem 40 has been rotated 135 degrees clockwise from the open state. Figure 13(j) to (l) show the state in which the valve stem 40 has been rotated 180 degrees clockwise from the open state to the closed state, which is the state in which the valve stem 40 has been rotated clockwise to the maximum extent.

[0247] That is, the butterfly valve 1 with the opening and closing mechanism Ys can switch from the open valve state, in which the valve stem 40 rotates counterclockwise to the closed valve state, in which the valve stem 40 rotates clockwise to the maximum extent, by rotating 180 degrees.

[0248] The following is about... Figure 13 The valve opening states shown in (a) to (c) represent the initial state to... Figure 13 The operation of the butterfly valve 1 with opening and closing mechanism Ys up to the closed state shown in (j) to (l) will be explained. In detail, the operation of the rotary movement conversion mechanism MDs, the rotary restriction mechanism MR, and the valve body 50 from the open state to the closed state will be explained.

[0249] In this specification, the valve-opening state of the opening / closing mechanism Ys, which is the initial state, is the same as the valve-opening state of the opening / closing mechanism Y, so its description is omitted. Furthermore, the rotation limiting mechanism MR at this time is also the same as the rotation limiting mechanism MR in the valve-opening state of the opening / closing mechanism Y, so its description is omitted.

[0250] In the open valve state, rotation is not restricted by the rotation limiting mechanism MR. Therefore, when the valve stem 40 is rotated clockwise by a specified angle, i.e., 90 degrees, from the open valve state, the cam 80s and cam connecting rod 90 rotate clockwise by 90 degrees along with the clockwise rotation of the valve stem 40 (see reference). Figure 13 (e)).

[0251] Furthermore, the boundary between the second arc-shaped portion 85s and the third arc-shaped portion 86s of the cam 80s abuts against the near-inner side surface 542s of the cam groove 54s, the first straight portion 82s abuts against the inner side surface 543s of the cam 54s, and the third straight portion 87s abuts against the inner side surface of the left side WL of the cam groove 54s. Therefore, as the valve stem 40 and the cam 80s rotate, the pressing base 51s also rotates 90 degrees clockwise (see reference). Figure 13 (d), (e), (f)). Therefore, the valve body 50 installed on the vertical part 52 of the insert base 51s is in a position facing the forward side DF, but there is a gap between it and the seat ring 20 installed on the mounting part 111, and it is not in a sealed state (see reference). Figure 13 (f)

[0252] In addition, Figure 13In the rotation-limiting state shown in (d), (g), and (h), a frame opening 632 is provided near the front side DF of the convex portion 71, which faces along the depth direction D in the long axis direction, thus allowing movement of the front side DF of the convex portion 71. That is, when the valve stem 40 is rotated clockwise to a position of 90 degrees from the initial state, the rotation-limiting mechanism MR functions as a movement direction limiting unit that restricts further rotation of the convex portion 71 but allows the convex portion 71 to move towards the front side DF.

[0253] Then, as the valve stem 40 is further rotated to a position of 135 degrees, the cam 80s and the cam link 90 also rotate to a position of 135 degrees (see reference). Figure 13 (g), (h), (i)). However, even if cam 80s and cam link 90 rotate, as Figure 13 As shown in (d), since the side of the convex portion 71 abuts against the round side frame 634, further clockwise rotation of the convex portion 71 is limited by the rotation limiting mechanism MR, and the push-in base 51s and guide 70 on which the valve body 50 is mounted do not rotate (see Figure 1). Figure 13 (g)).

[0254] Thus, by rotating the valve stem 40 at an angle exceeding the specified angle of 90 degrees, when the cam 80s rotates clockwise relative to the cam groove 54s provided in the pressing base 51s, the pressing base 51s moves towards the front DF through the arc-shaped portions 85s and 88s in the cam 80s.

[0255] Specifically, in the second arc-shaped portion 85s that abuts against the near-inner side surface 542s of the cam groove 54s as described above, the distance from the first center Fc gradually increases from the boundary with the third arc-shaped portion 86s toward the boundary with the second arc-shaped portion 85s. In the fourth arc-shaped portion 88s that abuts against the inner side surface 543s of the cam groove 54s, the distance from the first center Fc gradually decreases from the boundary with the first straight portion 82s toward the boundary with the third straight portion 87s.

[0256] Therefore, in the second arc-shaped portion 85s, the distance between the part abutting the near-inner side 542s of the cam groove 54s and the first center Fc gradually increases, and the near-inner side 542s of the cam groove 54s is pressed into the near-inner side DF by the clockwise rotating second arc-shaped portion 85s. Conversely, in the clockwise rotating fourth arc-shaped portion 88s, the distance between the part abutting the inner side 543s of the cam groove 54s and the first center Fc gradually decreases. That is, it approaches the first center Fc.

[0257] Additionally, at this time, the through hole 73 of the guide 70 is oriented along the depth direction D in the long axis direction, and the convex part 71 can move relative to the valve stem 40 through the frame opening 632 of the rotation limiting groove 63 towards the forward side DF (see reference). Figure 13 (g)).

[0258] Therefore, by rotating the valve stem 40 at an angle exceeding the specified angle of 90 degrees, when the cam 80s rotates clockwise relative to the cam groove 54s provided on the pressing base 51s, the near-front inner surface 542s of the cam groove 54s is pressed into the near-front side DF by the second arc-shaped portion 85s in the cam 80s, and the pressing base 51s moves towards the near-front side DF. Furthermore, since the length of the imaginary line VL passing through the second center Sc and connecting any point on the second arc-shaped portion 85s with any point on the fourth arc-shaped portion 88s is set to be equal to the depth length DL of the cam groove 54s, even if the valve stem 40 rotates beyond a specified angle, i.e., 90 degrees, the second arc-shaped portion 85s abuts against the near-inner side surface 542s of the cam groove 54s, and rotates with the inner side surface 543s of the cam groove 54s abutting against the fourth arc-shaped portion 88s. That is, the pressing base 51s can be moved towards the near-inner side DF, and no gap will be generated between the cam 80s in the depth direction D and the abutted surface 541s of the cam groove 54s.

[0259] In this state, when the valve stem 40 is further rotated to a 180-degree position, the cam 80s and the cam connecting rod 90 also rotate to a 180-degree position (see reference). Figure 13 (l)), but the insert base 51s, in which the base portion 72 is fitted in the configuration slot 55, does not rotate (see reference). Figure 13 As described above, the push-in base 51s, on which the valve body 50 is mounted, moves toward the front side DF, and the valve body 50 comes into close contact with the seat ring 20 mounted on the mounting part 111, thereby sealing the flow opening 112.

[0260] Additionally, at this time, the over-rotation prevention bolt 95 of the horizontal arm 91 installed on the cam link 90 abuts against the vertical part 52, limiting the further clockwise relative rotation of the cam link 90 with respect to the pressed base 51s.

[0261] Thus, the valve stem 40 can be rotated clockwise to a 180-degree position from the initial open state to become the closed state, but when the valve stem 40 is rotated counterclockwise to a 180-degree position from the closed state, it can become the open state.

[0262] Specifically, when the valve stem 40 is rotated counterclockwise to a specified angle of 90 degrees, the cam 80s and the cam connecting rod 90 also rotate counterclockwise by 90 degrees, but the pressing base 51 does not rotate. Therefore, when the cam 80s rotates counterclockwise relative to the cam groove 54s provided on the pressing base 51s, the inner side 543s of the cam groove 54s is pressed inward toward the inner side DB by the fourth arc-shaped portion 88s in the cam 80s, and the pressing base 51s moves inward toward the inner side DB.

[0263] Furthermore, since the length of the imaginary line VL, which passes through the second center Sc and connects any point on the second arc-shaped portion 85s with any point on the fourth arc-shaped portion 88s, is set to be equal to the depth length DL of the cam groove 54s, even if the valve stem 40 rotates counterclockwise from the closed state, it rotates while the inner side 543s of the cam groove 54s abuts against the fourth arc-shaped portion 88s and the near-front inner side 542s of the cam groove 54s abuts against the second arc-shaped portion 85s. This allows the pressing base 51s to move inwards to DB without creating a gap between the cam 80s in the depth direction D and the abutted surface 541s of the cam groove 54s.

[0264] That is, in the cam groove 54s, the cam 80s rotates 90 degrees counterclockwise and presses into the base 51 to move inward to DB, that is, the valve body 50 is pulled inward to DB, so the tight contact state of the valve body 50 relative to the seat ring 20 is released.

[0265] Then, as the valve stem 40 is further rotated counterclockwise to a position of 180 degrees, i.e., the open valve position, the cam 80s and cam connecting rod 90 also rotate counterclockwise to a position of 180 degrees, i.e., the open valve position, along with the rotation of the cam 80s and cam connecting rod 90. Moreover, along with the rotation of the cam 80s and cam connecting rod 90, the push-in base 51s on which the valve body 50 is mounted and the guide 70 also rotate counterclockwise to a position of 180 degrees, i.e., the open valve position, thus achieving the open valve state.

[0266] As described above, in addition to the functions of the butterfly valve 1 with opening and closing mechanism Ys, the butterfly valve 1 with opening and closing mechanism Ys also performs the following functions.

[0267] Specifically, the butterfly valve 1 with the opening and closing mechanism Ys includes: a valve housing 10 having a tubular flow path F; a valve stem 40 rotatably disposed on the valve housing 10; a valve body 50 that rotates via the valve stem 40 to open and close the flow path F; and a seat ring 20 disposed between the valve housing 10 and the valve body 50. A rotational movement conversion mechanism MDs is disposed between the valve stem 40 and the valve body 50. This rotational movement conversion mechanism MDs causes the valve body 50 to rotate as the valve stem 40 rotates from the open position to 90 degrees, and the valve body 50 moves in close contact with the seat ring 20 by rotating the valve stem 40 more than 90 degrees. The direction in which the valve body 50 moves in close contact with the seat ring 20 is set as the forward side DF, and the opposite direction is set as the inward side DB. The rotary movement conversion mechanism MDs has a cam 80s provided on the valve stem 40 and a cam groove 54s provided on the push-in base 51 integrated with the valve body 50 for the cam 80s to be embedded. The cam groove 54s has an abutting surface 541s separated by a depth length DL on the forward side DF. The cam 80s has two arc-shaped portions 85s and 88s centered on a second center Sc. The second center Sc is eccentric to the first center Fc, which is the rotation center of the valve stem 40. Two arc-shaped portions 85s and 88s are arranged opposite each other across the second center Sc, and the length of the imaginary line VL that passes through the second center Sc and connects the two arc-shaped portions 85s and 88s is set to be equal to the depth length DL. By rotating the valve stem 40 by more than 90 degrees, the contact surface 541s, which is arranged in the cam groove 54s and is separated from the depth length DL, abuts against the two arc-shaped portions 85s and 88s, so that the valve body 50 moves from the first center Fc of the valve stem 40 along the flow path F in a manner that is in close contact with the seat ring 20.

[0268] Therefore, a stable and high compression surface pressure can be obtained.

[0269] Specifically, the rotary movement switching mechanism MDs in the butterfly valve 1, which opens and closes the flow path F of the valve housing 10 by rotating the valve body 50 using the valve stem 40 to abut against the seat ring 20, can rotate the valve body 50 along with the valve stem 40 from the open position to 90 degrees, and move the valve body 50 in close contact with the seat ring 20 by rotating the valve stem 40 more than 90 degrees.

[0270] Additionally, the rotary movement conversion mechanism MDs has a cam 80s disposed on the valve stem 40 and a cam groove 54s disposed on the push-in base 51 integrated with the valve body 50. The cam groove 54s is into which the cam 80s is inserted and has an abutting surface 541s spaced apart by the depth length DL along the depth direction D. The cam 80s has two arc-shaped portions 85s and 88s centered on a second center Sc, which is eccentric relative to the first center Fc, which is the rotation center of the valve stem 40. The two arc-shaped portions 85s and 88s are arranged in opposite directions across the second center Sc, and the length of the imaginary line VL passing through the second center Sc and connecting the two arc-shaped portions 85s and 88s is set to be equal to the depth length DL.

[0271] In the rotary movement conversion mechanism MDs that constitutes the cam 80s and the cam groove 54s, as the valve stem 40 rotates more than 90 degrees, the cam 80s rotates relative to the cam groove 54s. The abutting surface 541s, which is arranged in the cam groove 54s with a depth length DL separated, abuts against two arc-shaped portions 85s and 88s, so that the valve body 50 moves from the first center Fc of the valve stem 40 along the flow path F in a manner that is in close contact with the seat ring 20.

[0272] Therefore, in the closed state, the valve body 50 and the seat ring 20 are in close contact under a high compressive surface pressure. Thus, even when cutting off the flow of fluids with small molecular sizes or extremely low-temperature fluids such as cryogenic fluids, the flow path F can be reliably cut off, and fluid will not flow out between the seat ring 20 and the valve body 50.

[0273] Furthermore, the contact surface 541s in the cam groove 54s is arranged apart from the depth length DL. Two arc-shaped portions 85s and 88s, arranged opposite each other across the second center Sc, are configured such that the length of the imaginary line VL connecting the two arc-shaped portions 85s and 88s is equal to the depth length DL. Therefore, when the cam 80s rotates relative to the cam groove 54s, no clearance is generated between the contact surface 541s, arranged apart from the depth length DL, and the two arc-shaped portions 85s and 88s. Therefore, by rotating the valve stem 40 by more than 90 degrees, the valve body 50 can be moved from the first center Fc of the valve stem 40 along the flow path F in a stable state, in close contact with the seat ring 20.

[0274] In addition, the two arc-shaped portions 85s and 88s have different diameters. The arc-shaped portions 85s and 88s are configured to be oppositely oriented with a gap between them and the second center Sc. The length of the imaginary line VL that passes through the second center Sc and connects the second arc-shaped portion 85s and the fourth arc-shaped portion 88s is equal to the depth length DL. By rotating the valve stem 40 by more than 90 degrees, the contact surface 541s, which is configured with a gap between the depth length DL and the arc-shaped portions 85s and 88s in the cam groove 54s, abuts against the arc-shaped portions 85s and 88s.

[0275] Therefore, even if the eccentricity of the second center Sc relative to the first center Fc varies in various ways, it can reliably abut against the contact surface 541s, allowing the valve body 50 to move along the flow path F from the first center Fc of the valve stem 40 in a manner that is in close contact with the seat ring 20.

[0276] In addition, with the valve stem 40 rotated 90 degrees, the second center Sc is eccentric to the inward side DB relative to the first center Fc, the second arc-shaped portion 85s is positioned on the side near the front DF relative to the second center Sc, and the fourth arc-shaped portion 88s is positioned on the side of the inward side DB relative to the second center Sc.

[0277] Therefore, even when the second center Sc is eccentrically positioned towards the inward DB relative to the first center Fc after a 90-degree rotation, the second arc-shaped portion 85s on the side near the front DF relative to the second center Sc and the fourth arc-shaped portion 88s on the side inward DB relative to the second center Sc can abut against the contact surface 541s, causing the valve body 50 to move along the flow path F from the first center Fc of the valve stem 40 in close contact with the seat ring 20. Furthermore, during reverse rotation, the valve body 50, which is in close contact with the seat ring 20, can also move away along the flow path F towards the inward DB after abutting against the contact surface 541s.

[0278] In addition, a rotation limiting mechanism MR is provided, which allows the valve body 50 to rotate from the valve stem 40 in the open position to 90 degrees, limits the rotation of the valve body 50 to more than 90 degrees along with the rotation of the valve stem 40, and allows the valve body 50 to move in the direction of close contact with the seat ring 20.

[0279] Therefore, by means of the rotation limiting mechanism MR, the rotation of the valve body 50 that accompanies the rotation of the valve stem 40 by more than 90 degrees can be limited, and in the closed state, the valve body 50 is moved in the direction of close contact with the seat ring 20 by means of the rotation movement conversion mechanism MDs, so as to reliably cut off the flow path F.

[0280] In addition, the cam groove 54s is formed to be larger in the width direction W than the depth length DL in the depth direction D, but the rotation limiting mechanism MR can prevent the pressing base 51s from accidentally shifting in the width direction W.

[0281] In addition, the contact surface 541s provided in the cam groove 54s is formed by surfaces (542s, 543s) extending in the width direction W. The cam 80s is provided with a first straight portion 82s that contacts the inner side surface 543s (541s) in the open valve state and a second straight portion 84s that contacts the near front inner side surface 542s (541s) in the closed valve state.

[0282] Therefore, in the open valve state, the first straight portion 82s of the cam 80s contacts the inner side surface 543s (541s) formed by the surface extending in the width direction W on the inner side DB, and in the closed valve state, the second straight portion 84s of the cam 80s contacts the near-front inner side surface 542s (541s) formed by the surface extending in the width direction W on the near-front side DF, thus enabling stable maintenance of each state.

[0283] In addition, the first straight section 82s and the second straight section 84s are in surface contact with the contact surface 541s, thus preventing excessive rotation of the valve stem 40 beyond the surface contact state.

[0284] Next, with the following appendix Figure 13 Another embodiment of the present invention will now be described.

[0285] Figure 13 An explanatory diagram of another embodiment of the rotary-movement conversion mechanism MDt is shown. Figure 13 An explanatory diagram showing the opening and closing operation of a butterfly valve 1 with an opening and closing mechanism Yt having other embodiments is provided.

[0286] Specifically, Figure 13 Images (a) to (c) show the butterfly valve 1 with opening and closing mechanism Yt in the open state. Figure 13 The diagrams corresponding to (a) to (c).

[0287] Figure 13 Figures (a) to (l) show the butterfly valve 1 with opening and closing mechanism Yt and Figure 13 The diagrams corresponding to (a) to (l).

[0288] Furthermore, in the above figures, in the butterfly valve 1 with opening and closing mechanism Yt, the same reference numerals are used for structures that are the same as those in the butterfly valve 1 with opening and closing mechanisms Y and Ys, and their descriptions are omitted.

[0289] The opening and closing mechanism Yt in butterfly valve 1 is different from cam 80t in the opening and closing mechanism Ys mentioned above, except that the other structures are the same as the other structures in the opening and closing mechanism Ys. Cam 80t will be described in detail.

[0290] As mentioned above, in Figure 13 In the valve-open state shown in (b), compared to the cam 80s which has a first straight section 82s, a first arc-shaped section 83s, a second straight section 84s, a second arc-shaped section 85s, a third arc-shaped section 86s, a third straight section 87s, and a fourth arc-shaped section 88s arranged sequentially from the inside DB in a clockwise direction when viewed from above, the cam 80t has a top-view shape with a second straight section 84s, a first arc-shaped section 83s, a first straight section 82s, a fourth arc-shaped section 88s, a third straight section 87s, a third arc-shaped section 86s, and a second arc-shaped section 85s arranged sequentially from the inside DB in a clockwise direction when viewed from above. That is, Figure 13 As shown in (c), the cam 80t in the open valve state is connected by a 45-degree inclined imaginary line VL2 (refer to) connecting the left WL and the near-front DF with the right WR and the inner DB. Figure 13 (a) is symmetrical, and will Figure 13 The orientation obtained by reversing the cam 80s in the open valve state shown in (c).

[0291] Therefore, as Figure 13 As shown in (b), compared to cam 80s which eccentricates the second center Sc toward the inner side DB of the first center Fc, the second center Sc in cam 80t is positioned on the right side WR relative to the first center Fc.

[0292] In addition, the opening and closing mechanism Yt, which includes the push-in base 51s with cam groove 54s and cam 80t, is configured with cam 80t facing in a top view in the cam groove 54s, which is formed to be larger in width direction W than in depth direction D, with the second straight portion 84s becoming the inner side DB, the first straight portion 82s becoming the right side WR and the third straight portion 87s becoming the near front side DF.

[0293] At this time, the second straight section 84s in the cam 80t abuts against the inner side 543s of the cam groove 54s, which is formed to be roughly rectangular in shape when viewed from above, with a width greater than that in the depth direction D. The third straight section 87s abuts against the near-inner side 542s of the cam groove 54s.

[0294] In addition, the boundary between the second arc-shaped portion 85s and the third arc-shaped portion 86s abuts against the inner side of the left side WL of the cam groove 54s.

[0295] Furthermore, the second straight portion 84s and the third straight portion 87s, which are formed as straight lines when viewed from above, are in a state of being opposed to and abutting the contact surface 541s of the cam groove 54s in the depth direction D, i.e., surface contact.

[0296] In addition, the contact between a portion of the cam 80s and the contact surface 541s of the cam groove 54s can be an actual contact or a gap of a certain tolerance.

[0297] Next, the following describes the case where the valve stem 40 rotates beyond a specified angle in the opening and closing mechanism Yt.

[0298] Furthermore, in the opening and closing mechanism Yt, the action of making the valve stem 40 exceed the specified angle, i.e., 90 degrees, is the same as the action of the opening and closing mechanisms Y and Ys mentioned above, so the explanation is omitted.

[0299] in addition, Figure 13 (a) ~ Figure 13 (c) shows the valve open state with the valve stem 40 rotated counterclockwise to its maximum extent. Figure 13 Figures (d) to (f) show the state in which the valve stem 40 has been rotated 90 degrees clockwise from the open position. Figure 13 (g) to (i) show the state where the valve stem 40 has been rotated 135 degrees clockwise from the open state. Figure 13 (j) to (l) show the state in which the valve stem 40 has been rotated 180 degrees clockwise from the open state, and the closed state in which the valve stem 40 has been rotated clockwise to the maximum extent.

[0300] In this way, the butterfly valve 1 with the opening and closing mechanism Yt can switch from the open state, in which the valve stem 40 rotates to the maximum extent counterclockwise, to the closed state, in which the valve stem 40 rotates to the maximum extent clockwise, by rotating 180 degrees.

[0301] In addition, Figure 13 In the open valve state shown in (b), the third linear portion 87s and the second linear portion 84s of the cam 80t abut against the contact surfaces 541s (542s, 543s) on both sides of the depth direction D of the cam groove 54s. Therefore, during the rotation of the valve stem 40 up to the specified angle of 90 degrees, the cam 80t and the cam connecting rod 90 also rotate together with the pressing base 51s.

[0302] When the valve stem 40 is rotated clockwise from the open position by more than a specified angle, i.e., 90 degrees, to a position such as 135 degrees, the cam 80t and the cam link 90 also rotate to the 135-degree position (see reference). Figure 13 (g), (h), (i)), but the base 51s and guide 70 are restricted from further clockwise rotation by the rotation limiting mechanism MR (see reference). Figure 13(g)).

[0303] Thus, when the cam 80t rotates clockwise relative to the cam groove 54s provided in the pressing base 51s by rotating the valve stem 40 by more than a specified angle, i.e., 90 degrees, the pressing base 51s moves towards the front DF through the second arc-shaped portion 85s and the fourth arc-shaped portion 88s in the cam 80t.

[0304] Specifically, in the fourth arc-shaped portion 88s that abuts against the near-inner side surface 542s of the cam groove 54s as described above, the distance from the first center Fc gradually increases from the boundary with the third straight portion 87s toward the boundary with the first straight portion 82s. In the second straight portion 84s that abuts against the inner side surface 543s of the cam groove 54s, the distance from the first center Fc gradually decreases from the boundary with the second straight portion 84s toward the boundary with the third arc-shaped portion 86s.

[0305] Therefore, in the fourth arc-shaped portion 88s, the distance between the part abutting the near-inner side 542s of the cam groove 54s and the first center Fc gradually increases, and the near-inner side 542s of the cam groove 54s is pressed into the near-inner side DF by the clockwise rotating fourth arc-shaped portion 88s. Conversely, in the clockwise rotating second arc-shaped portion 85s, the distance between the part abutting the inner side 543s of the cam groove 54s and the first center Fc gradually decreases. That is, it approaches the first center Fc.

[0306] Additionally, at this time, the through hole 73 of the guide 70 is oriented along the depth direction D in the long axis direction, and the convex part 71 can move relative to the valve stem 40 through the frame opening 632 of the rotation limiting groove 63 towards the forward side DF (see reference). Figure 13 (g)).

[0307] Therefore, when the cam 80t rotates clockwise relative to the cam groove 54s provided on the pressing base 51s by rotating the valve stem 40 by more than a specified angle, i.e., 90 degrees, the near-front inner surface 542s of the cam groove 54s is pressed into the near-front side DF by the fourth arc-shaped portion 88s in the cam 80t, and the pressing base 51s moves towards the near-front side DF. Furthermore, the length of the imaginary line VL, which passes through the second center Sc and connects any point on the fourth arc-shaped portion 88s with any point on the second arc-shaped portion 85s, is set to be equal to the depth length DL of the cam groove 54s. Therefore, even if the valve stem 40 rotates beyond the specified angle of 90 degrees, it rotates with the fourth arc-shaped portion 88s abutting against the near-inner side 542s of the cam groove 54s and the inner side 543s of the cam groove 54s abutting against the second arc-shaped portion 85s. This allows the pressing base 51s to move towards the near-inner side DF, preventing a gap from forming between the cam 80t in the depth direction D and the abutted surface 541s of the cam groove 54s.

[0308] In this state, when the valve stem 40 is further rotated to a 180-degree position, the cam 80t and the cam connecting rod 90 rotate to a 180-degree position (see reference). Figure 13 (l)), but the insert base 51s, in which the base portion 72 is fitted in the configuration slot 55, does not rotate (see reference). Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 Figure 13 As described above, the push-in base 51s, on which the valve body 50 is mounted, moves toward the front side DF, and the valve body 50 comes into close contact with the seat ring 20 mounted on the mounting part 111, thereby sealing the flow opening 112.

[0309] In addition, when the valve stem 40 is rotated counterclockwise to a specified angle of 90 degrees, the cam 80t and the cam connecting rod 90 rotate counterclockwise by 90 degrees, but the pressing base 51 does not rotate. Therefore, the inner side 543s of the cam groove 54s is pressed into the inner side DB by the second arc-shaped part 85s in the cam 80t, and the pressing base 51s moves inward to the DB.

[0310] Furthermore, since the length of the imaginary line VL, which passes through the second center Sc and connects any point on the fourth arc-shaped portion 88s with any point on the second arc-shaped portion 85s, is set to be equal to the depth length DL of the cam groove 54s, even if the valve stem 40 rotates counterclockwise from the closed state, it rotates with the inner side 543s of the cam groove 54s abutting against the second arc-shaped portion 85s and the near-front inner side 542s of the cam groove 54s abutting against the fourth arc-shaped portion 88s. This allows the pressing base 51s to move inwards to DB without creating a gap between the cam 80t in the depth direction D and the abutted surface 541s of the cam groove 54s.

[0311] That is, the cam 80s rotates 90 degrees counterclockwise in the cam groove 54s and moves into the base 51 inwards DB, thereby pulling the valve body 50 inwards DB, thus releasing the tight contact between the valve body 50 and the seat ring 20.

[0312] Then, as the valve stem 40 is further rotated counterclockwise to a position of 180 degrees, i.e., the open valve position, the cam 80t and cam connecting rod 90 also rotate counterclockwise to a position of 180 degrees, i.e., the open valve position, along with the rotation of the cam 80t and cam connecting rod 90. Moreover, as the cam 80t and cam connecting rod 90 rotate, the push-in base 51s and guide 70, on which the valve body 50 is mounted, also rotate counterclockwise to a position of 180 degrees, i.e., the open valve position, thus achieving the open valve state.

[0313] As described above, the butterfly valve 1 with opening and closing mechanism Yt, in addition to the functions performed in the butterfly valve 1 with opening and closing mechanism Y and the butterfly valve 1 with opening and closing mechanism Ys, also performs the following functions.

[0314] Specifically, the second center Sc is eccentric to the front DF and right WR relative to the first center Fc when the valve stem 40 is rotated 90 degrees. The second arc-shaped portion 85s is positioned on the inner DB side relative to the second center Sc and left WL. The fourth arc-shaped portion 88s is positioned on the front DF side relative to the second center Sc and right WR.

[0315] Therefore, even when rotated 90 degrees, the opening and closing mechanism Yt, which is eccentric to the front DF and right WR relative to the first center Fc, can still have its second arc-shaped portion 85s (located on the inner DB side relative to the second center Sc and with its left WL) and its fourth arc-shaped portion 88s (located on the inner DF side relative to the second center Sc and with its right WR) abut against the contact surface 541s, causing the valve body 50 to move from the first center Fc of the valve stem 40 along the flow path F in a manner that is in close contact with the seat ring 20. Furthermore, even during reverse rotation, it can still abut against the contact surface 541s, causing the valve body 50, which is in close contact with the seat ring 20, to move away along the flow path F towards the inner DB side.

[0316] In the above correspondence between the structure of the present invention and the foregoing embodiments, the flow path of the present invention corresponds to flow path F.

[0317] Similarly,

[0318] Valve housing corresponds to valve housing 10, valve stem corresponds to valve stem 40, valve body corresponds to valve body 50, seat ring corresponds to seat ring 20, rotary movement conversion mechanism corresponds to rotary movement conversion mechanisms MD, MDs, MDt, cam body corresponds to cams 80, 80s, 80t, cam groove corresponds to cam grooves 54, 54s, butterfly valve corresponds to butterfly valve 1, specified angle corresponds to 45 degrees or 90 degrees, pressing direction corresponds to the near-front side DF, concave part corresponds to the large arc-shaped part 543, pressing surface corresponds to the straight part 542, rotation limiting mechanism corresponds to rotation limiting mechanism MR, axial direction corresponds to height direction H, transmission component corresponds to cam connecting rod 90, edge part corresponds to horizontal arm 91 and vertical connection part 92, over-rotation limiting part corresponds to over-rotation anti-bolt 95, specified angle corresponds to 90 degrees. Correspondingly, the moving direction corresponds to the near front side DF, the reverse moving direction corresponds to the inner side DB, the abutted part corresponds to the abutted surface 541s, the axis corresponds to the first center Fc, the eccentric center corresponds to the second center Sc, the arc-shaped part corresponds to the second arc-shaped part 85s and the fourth arc-shaped part 88s, the imaginary line corresponds to the imaginary line VL, the specified interval corresponds to the depth length DL, the large-diameter arc-shaped part corresponds to the second arc-shaped part 85s, the small-diameter arc-shaped part corresponds to the fourth arc-shaped part 88s, the vertical direction corresponds to the width direction W, the side opposite to the side where the eccentric center is located corresponds to the left side WL, the side where the eccentric center is located corresponds to the right side WR, the valve opening abutted surface corresponds to the first straight part 82s, and the valve closing abutted surface corresponds to the second straight part 84s, but it is not limited to the above-described embodiment.

[0319] For example, the butterfly valve 1 with the above-mentioned opening and closing mechanisms Y, Ys, and Yt is a central butterfly valve, but it can also be configured as a primary eccentric butterfly valve or a secondary eccentric butterfly valve.

[0320] In addition, in the above description, the butterfly valve 1 with opening and closing mechanism Y achieves the above action by having a rotational movement conversion mechanism MD and a rotational restriction mechanism MR. However, it is also possible to not have a rotational restriction mechanism MR, but instead rotate the valve stem 40 to a position of 90 degrees and use the rotational load generated by the contact between the valve body 50 and the seat ring 20 to move.

[0321] In this configuration, the rotation of the valve body 50, which accompanies the clockwise rotation of the valve stem 40 exceeding 90 degrees, can be restricted without the need for a rotation limiting mechanism MR. Simultaneously, in the closed state, the valve body 50 is moved forward towards the DF via the rotational movement switching mechanism MD, reliably cutting off the flow path F. Therefore, compared to the case where a rotation limiting mechanism MR is provided, a butterfly valve 1 with a simpler opening and closing mechanism Y can be constructed.

[0322] In addition, in the description of the butterfly valve 1 with the above-mentioned opening and closing mechanism Y, the valve stem 40 is rotated clockwise to a position of 45 degrees from the initial open state, and the relative rotation of the convex part 71 is restricted by the rotation limiting mechanism MR. When the rotation exceeds 135 degrees, the arc-shaped part 84 presses the straight part 542 of the cam groove 54s, causing the valve body 50 to move towards the front side DF and come into close contact with the seat ring 20. However, it is not limited to the above-mentioned angle and can be set to an appropriate angle.

[0323] Alternatively, it can be configured such that when rotated to a 90-degree position, the relative rotation of the convex portion 71 is restricted by the rotation limiting mechanism MR. When the rotation exceeds 90 degrees, the arc-shaped portion 84 presses the straight portion 542 of the cam groove 54s, causing the valve body 50 to move towards the front side DF and come into close contact with the seat ring 20.

[0324] Furthermore, the shape of the rotation limiting groove 63 in the rotation limiting mechanism MR is not limited to the shape described above. For example, the arc frame 633 may be formed in a circumferential shape, and the frame opening 632 may not be an opening, but rather a recess in the circumferential arc frame 633. The circular side frame 634 that limits the rotation of the convex part 71 may also be composed of a convex part that protrudes from the inner surface of the circumferential arc frame 633.

[0325] Regarding the valve stem 40, valve stem 40A and valve stem 40B are provided, and the rotation of valve stem 40A is transmitted to the rotational movement conversion mechanism MD, MDs, MDt or rotational limiting mechanism MR on the lower side HD by a cam link 90. ​​However, it can also be composed of a single valve stem 40 that passes through the insert bases 51, 51s, 51t along the height direction H. In this case, the cam link 90 is not required, but it is also possible to provide an edge portion on the valve stem 40, as with the cam link 90, so that the portion of the valve stem 40 disposed between the horizontal portions 53, 53s, 53t of the insert bases 51, 51s, 51t is offset from the axis in a predetermined direction.

[0326] In addition, in the above description, by rotating the shifting mechanism MD, MDs, MDt, the valve body 50 is moved in the direction of the fluid flowing from the inner side DB toward the near front side DF (i.e. toward the near front side DF) and comes into close contact with the seat ring 20. However, the direction of movement of the valve body 50 caused by the rotating shifting mechanism MD, MDs, MDt does not need to be along the direction of fluid flow. The direction of contact between the valve body 50 and the seat ring 20 can also be a direction that intersects with the direction of fluid flow.

[0327] In addition, in the above description, in the rotary movement conversion mechanism MD, MDs, MDt, the cams 80, 80s, 80t are connected to the valve stem 40, and the push-in bases 51, 51s, 51t on which the valve body 50 is installed are provided with cam grooves 54, 54s. However, the cam grooves can also be provided on the valve stem 40, and the push-in bases 51, 51s, 51t on which the valve body 50 is installed are provided with cams.

[0328] Furthermore, in the above description, the butterfly valve 1 with opening and closing mechanisms Y, Ys, and Yt is configured to switch from an open valve state in which the valve stem 40 rotates counterclockwise to the maximum extent and to a closed valve state in which the valve stem 40 rotates clockwise to the maximum extent by rotating 180 degrees. However, the butterfly valve 1 with opening and closing mechanisms Y, Ys, and Yt can also be configured such that the valve stem 40 rotates counterclockwise to change from an open valve state to a closed valve state.

[0329] In addition, in the case of the opening and closing mechanisms Ys and Yt mentioned above, the over-rotation prevention bolt 95 provided on the hook-shaped part 94 of the cam link 90 and the hook-shaped part 94 itself may not be provided.

[0330] Specifically, in the opening and closing mechanism Ys, in the open valve state, the first linear portion 82s and the third linear portion 87s abut against the contact surface 541s of the cam groove 54s, and in the closed valve state, the second linear portion 84s and the third linear portion 87s abut against the contact surface 541s of the cam groove 54s, thus enabling stable maintenance of each state.

[0331] Furthermore, the length of the imaginary line VL connecting the boundary of the first straight portion 82s that abuts against the inner side 543s of the cam groove 54 in the open state with the point on the third arc-shaped portion 86s that passes through the first center Fc, and the length of the imaginary line VL connecting the boundary of the second arc-shaped portion 85s that abuts against the near-front inner side 542s of the cam groove 54 in the closed state with the point on the third arc-shaped portion 86s that passes through the first center Fc, is the longest in the cam 80s, thus preventing excessive rotation of the valve stem 40 centered on the first center Fc.

[0332] Furthermore, the length of the imaginary line VL connecting the boundary of the second straight section 84s that abuts against the inner side 543s of the cam groove 54 in the open state with the point on the third arcuate section 86s that passes through the first center Fc, and the length of the imaginary line VL connecting the boundary of the first straight section 82s that abuts against the near inner side 542s of the cam groove 54 in the closed state with the point on the third arcuate section 86s that passes through the first center Fc, is the longest in the cam 80t, thus preventing excessive rotation of the valve stem 40 centered on the first center Fc.

[0333] Therefore, in the opening and closing mechanisms Ys and Yt, even if the over-rotation prevention bolt 95 is not provided on the hook portion 94 of the cam link 90, even if the cam link 90, which is straight when viewed from above, does not originally have the hook portion 94, it is possible to prevent over-rotation centered on the first center Fc.

[0334] The aforementioned cam groove 54s can have any top-view shape as long as it has a contact surface 541s separated by the depth length DL on the near-front side DF and is able to be rotatably inserted into the cam 80s. In addition, the contact surface 541s is planar and separated by the depth length DL, but it may not be a planar surface, for example, it may be a convex shape that makes point or line contact with the cams 80s and 80t.

[0335] The aforementioned arc shape centered on the second center Sc includes various curved shapes such as circular arc, elliptical arc, and oblong arc that protrude along a specified direction when viewed from above, and may also have inflection points.

[0336] Furthermore, in the aforementioned cam 80s, which has two arc-shaped portions 85s and 88s centered on a second center Sc that is eccentric to the first center Fc, which is the rotation center of the valve stem 40, the portions other than the arc-shaped portions 85s and 88s can be straight, or arc-shaped centered on the first center Fc, or arc-shaped with a center different from the first center Fc and the second center Sc, or even a combination thereof.

[0337] Furthermore, the two arc-shaped portions 85s and 88s centered on the second center Sc can have different diameters or the same diameter.

[0338] Label Explanation

[0339] 1: Butterfly valve; 10: Valve housing; 20: Seat ring; 40: Valve stem; 50: Valve body; 54, 54s: Cam groove; 80, 80s, 80t: Cam; 82s: First straight section; 84: Arc-shaped section; 84s: Second straight section; 85s: Second arc-shaped section; 88s: Fourth arc-shaped section; 90: Cam connecting rod; 91: Horizontal arm; 92: Vertical connection; 96: Over-rotation prevention bolt; 541s: Abutting surface; 542: Straight section; 543: Large arc-shaped section; DB: Inner side; DF: Near front side; DL: Depth length; F: Flow path; Fc: First center; H: Height direction; MD, MDs, MDt: Rotational movement conversion mechanism; MR: Rotation limiting mechanism; VL: Imaginary line; W: Width direction; WL: Left side; WR: Right side; Sc: Second center.

Claims

1. A butterfly valve, comprising: Valve housing, which has a tubular flow path; A valve stem, which is rotatably mounted on the valve body; A valve body, which rotates via the valve stem, opens and closes the flow path; and A seat ring is disposed between the valve housing and the valve body. A rotary-movement conversion mechanism is provided between the valve stem and the valve body. This mechanism causes the valve body to rotate along with the valve stem as it rotates from the valve-open position to a predetermined angle. Furthermore, by rotating the valve stem beyond the predetermined angle, the valve body moves in close contact with the seat ring. The rotary-movement conversion mechanism has: A cam body, disposed on either the valve stem or the valve body, has a protrusion in the circumferential direction whose diameter is longer than that of other portions; and A cam groove, which is located on either the valve stem or the valve body, allows the cam body to embed. The cam groove is provided with: A recessed portion, corresponding to the convex portion; and The pressing surface is continuous with the recess and is pressed in by the protrusion. By rotating the valve stem at an angle exceeding the specified angle, the protrusion disengages from the recess and presses into the pressing surface, causing the valve body to move from the axis of the valve stem along the flow path in a manner that is in close contact with the seat ring.

2. The butterfly valve according to claim 1, wherein, The butterfly valve is equipped with a rotation limiting mechanism that allows the valve body to rotate from the open position of the valve stem to the specified angle. The rotation limiting mechanism restricts the rotation of the valve body along with the rotation of the valve stem beyond the specified angle, and allows the valve body to move in a direction that is in close contact with the seat ring.

3. The butterfly valve according to claim 2, wherein, The rotary movement conversion mechanism and the rotary limiting mechanism are disposed on opposite sides of the valve body along the axial direction of the axis. The butterfly valve is provided with a transmission component that transmits the rotational force of the valve stem to the rotational movement conversion mechanism and the rotational restriction mechanism located on both sides of the valve body in the axial direction, on the side of the rotational movement conversion mechanism and the rotational restriction mechanism that does not receive rotational force from the valve stem.

4. The butterfly valve according to claim 3, wherein, The butterfly valve has a side portion provided on a part of the transmission component, which moves closer to the axis in a predetermined direction to suppress the reduction of the flow path area in the open valve state.

5. The butterfly valve according to any one of claims 1 to 4, wherein, The butterfly valve is provided with an over-rotation limiting part, which limits the over-rotation of the valve stem.

6. The butterfly valve according to claim 1, wherein, The butterfly valve moves by rotating the valve stem by a predetermined angle and utilizing the rotational load generated by the contact between the valve body and the seat ring.

7. A butterfly valve, comprising: Valve housing, which has a tubular flow path; A valve stem, which is rotatably mounted on the valve body; A valve body, which rotates via the valve stem, opens and closes the flow path; and A seat ring is disposed between the valve housing and the valve body. A rotary-movement conversion mechanism is provided between the valve stem and the valve body. This mechanism causes the valve body to rotate along with the valve stem as it rotates from the valve-open position to a predetermined angle. Furthermore, by rotating the valve stem beyond the predetermined angle, the valve body moves in close contact with the seat ring. The direction in which the valve body moves in close contact with the seat ring via the rotary movement conversion mechanism is defined as the movement direction, and the opposite direction is defined as the reverse movement direction. The rotary-movement conversion mechanism has: A cam body, which is disposed on either the valve stem or the valve body; and A cam groove, which is located on either the valve stem or the valve body, allows the cam body to embed. The cam groove has a contact portion spaced at a predetermined interval in the direction of movement. The cam body has at least two arc-shaped portions centered on an eccentric center, which is off-center relative to the axis that serves as the rotation center of the valve stem. The two arc-shaped portions are arranged opposite each other with a gap between them at the eccentric center, and the length of the imaginary line connecting the two arc-shaped portions, passing through the eccentric center, is set to be equal to the predetermined interval. By rotating the valve stem at an angle exceeding the specified angle, the abutting portion, which is spaced apart in the cam groove at the specified interval, abuts against the two arc-shaped portions, causing the valve body to move from the axis along the flow path in a manner that is in close contact with the seat ring.

8. The butterfly valve according to claim 7, wherein, The two arc-shaped portions have a large-diameter arc-shaped portion and a small-diameter arc-shaped portion with different diameters. The large-diameter arc-shaped portion and the small-diameter arc-shaped portion are arranged opposite each other with a gap between them at the eccentric center, and the length of the imaginary line connecting the large-diameter arc-shaped portion and the small-diameter arc-shaped portion, passing through the eccentric center, is set to be equal to the predetermined interval. By rotating the valve stem at an angle exceeding the predetermined angle, the large-diameter arcuate portion and the small-diameter arcuate portion abut against the abutting portion, which is arranged in the cam groove at the predetermined interval.

9. The butterfly valve according to claim 8, wherein, When the valve stem has been rotated by the specified angle, the eccentric center is eccentric relative to the axis in the opposite direction of movement. The large-diameter arc-shaped portion is positioned relative to the eccentric center on the side of the moving direction. The small-diameter arc-shaped portion is positioned on the opposite movement direction side relative to the eccentric center.

10. The butterfly valve according to claim 8, wherein, When the valve stem has been rotated by the specified angle, the eccentric center is eccentric relative to the axis in a direction perpendicular to the direction of movement. The large-diameter arc-shaped portion is positioned relative to the eccentric center on the opposite side of the direction of movement, and on the opposite side to the side where the eccentric center is located. The small-diameter arc-shaped portion is disposed on the side of the moving direction relative to the eccentric center, and on the side where the eccentric center is disposed.

11. The butterfly valve according to any one of claims 7 to 10, wherein, The butterfly valve is equipped with a rotation limiting mechanism that allows the valve body to rotate from the open position of the valve stem to the specified angle. The rotation limiting mechanism restricts the rotation of the valve body along with the rotation of the valve stem beyond the specified angle, and allows the valve body to move in a direction that is in close contact with the seat ring.

12. The butterfly valve according to claim 11, wherein, The abutted portion disposed in the cam groove is formed by a surface extending in a direction perpendicular to the direction of movement. The cam body is provided with: The valve-opening contact surface, which contacts the surface of the part being abutted when the valve is open; and The valve-closing contact surface contacts the contacted part surface when the valve is closed.

13. The butterfly valve according to claim 12, wherein, The rotary movement conversion mechanism and the rotary limiting mechanism are disposed on opposite sides of the valve body along the axial direction of the axis. The butterfly valve is provided with a transmission component that transmits the rotational force of the valve stem to the rotational movement conversion mechanism and the rotational restriction mechanism located on both sides of the valve body in the axial direction, on the side of the rotational movement conversion mechanism and the rotational restriction mechanism that does not receive rotational force from the valve stem.

14. The butterfly valve according to claim 13, wherein, The butterfly valve has a side portion provided on a part of the transmission component, which moves closer to the axis in a predetermined direction to suppress the reduction of the flow path area in the open valve state.

Images