Butterfly valve

Abstract

To provide a structure capable of ensuring sealing performance by absorbing assembly accuracy of a butterfly valve.SOLUTION: A butterfly valve comprises a body 2, a shaft 14 and an actuator 4. A valve body 12 has, at its outer peripheral part, a seal part which is attached / detached to / from an inner surface of a passage 10 to open / close the passage 10. The passage 10 includes a first passage 30 and a second passage 32, and has a spherical seal surface 48 at the intersection of the first passage 30 and the second passage 32. The seal part includes a first seal part S1 which is attached / detached to / from a cylindrical side face 46 of the second passage 32, and also seated on the side face 46 to lock the valve body 12 in a rotation direction, and a second seal part S2 which is slidable along the seal surface 48.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a butterfly valve. [Background technology]

[0002] Butterfly valves have a simple structure with a disk-shaped valve element attached to a shaft, and can be manufactured at relatively low cost. For this reason, they are often used to open, close, or switch fluid passages (see, for example, Patent Document 1). Such butterfly valves have a valve element made, for example, of a metal plate covered with an elastic material. When the valve element rotates, its outer periphery is pressed against the inner surface of the passage, thereby achieving a seal when the valve is closed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-203532 Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of butterfly valve, the disc seats on the inner surface of the passage at an angle relative to the passage axis, achieving a closed state or switching the passage. If the shaft and disc are assembled with sufficient precision, the disc will engage with the side of the passage during operation, causing its outer periphery to fit snugly against the inner surface of the passage, ensuring a tight seal. However, if the shaft or disc is assembled with inaccurate precision, one side of the disc's outer periphery may abut against the side of the passage, while the other side may float (i.e., create a gap). This would prevent a tight seal. In this case, it may be possible to force the valve into a closed state by further rotating the shaft and compressing the outer periphery. However, if the compression is excessive, the shaft's rotational torque increases, placing excessive strain on the actuator.

[0005] One object of the present invention is to provide a structure that can absorb the assembly precision of the butterfly valve and ensure sealing performance. [Means for solving the problem]

[0006] One aspect of the present invention is an electric butterfly valve that includes a body having a passage for passing a fluid, a shaft supported by the body so as to be rotatable about its own axis and extending radially of the passage, a valve element disposed in the passage while attached to the shaft and capable of opening and closing the passage by rotating together with the shaft, and an actuator that rotationally drives the shaft when energized.

[0007] The valve element has a seal portion on its outer periphery that is detachably attached to the inner surface of the passage to open and close the passage. The passage includes a first passage and a second passage, and a spherical seal surface is provided where the first and second passages intersect. The seal portion is detachably attached to the cylindrical side surface of the second passage and includes a first seal portion that is seated on the side surface to lock the valve element in the rotational direction, and a second seal portion that is slidable while in close contact with the seal surface.

[0008] In this configuration, a first seal portion is provided on one side of the outer periphery of the valve disc, and a second seal portion is provided on the other side. The first seal portion performs its sealing function when it engages with the side surface of the second passage, while the second seal portion performs its sealing function within the sliding range of the sealing surface. In other words, even if the sealing position of the first seal portion is limited, the sealing position of the second seal portion has an adjustable range, so even if the butterfly valve is not assembled with high precision, this can be accommodated to a certain extent, and sealing performance can be ensured. [Effects of the Invention]

[0009] According to the present invention, a structure can be provided that can absorb the assembly precision of the butterfly valve and ensure sealing performance. [Brief explanation of the drawings]

[0010] [Figure 1]1 is a diagram illustrating a configuration of a butterfly valve according to a first embodiment. FIG. [Figure 2] 1 is a diagram illustrating a configuration of a butterfly valve according to a first embodiment. FIG. [Figure 3] FIG. 2 is a perspective view showing the structure of a body. [Figure 4] FIG. 2 is a diagram showing the structure of a valve body. [Figure 5] 5A and 5B are diagrams illustrating the opening and closing operation of the valve body. [Figure 6] 10A and 10B are diagrams illustrating the effect of the seal structure of the embodiment. [Figure 7] 10A and 10B are diagrams showing the structure of a valve body according to a modified example. [Figure 8] FIG. 6 is a diagram illustrating the configuration of a butterfly valve according to a second embodiment. [Figure 9] 5A and 5B are diagrams illustrating the opening and closing operation of the valve body. [Figure 10] FIG. 10 is a diagram illustrating the configuration of a butterfly valve according to a third embodiment. [Figure 11] 5A and 5B are diagrams illustrating the opening and closing operation of the valve body. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. For convenience, the following description may refer to the positional relationship of each structure based on the illustrated state. In the following embodiments and their modifications, substantially identical components will be designated by the same reference numerals, and their description will be omitted where appropriate.

[0012] [First embodiment] In this embodiment, the butterfly valve is configured as a switching valve applied to a refrigeration cycle of a vehicle air conditioner. This vehicle air conditioner has a refrigeration cycle in which a compressor, a condenser, an expansion device, an evaporator, and other components (not shown) are connected by piping, and air conditioning is performed within the vehicle cabin as a refrigerant circulates through the refrigeration cycle while changing state. For example, HFO-1234yf or the like is used as the refrigerant. This butterfly valve is installed at a predetermined position in the refrigeration cycle and functions as a three-way valve that can switch the refrigerant flow path.

[0013] Figures 1 and 2 are diagrams showing the configuration of a butterfly valve according to a first embodiment. Figure 1(A) is a perspective view, and Figure 1(B) is a longitudinal cross-sectional view. Figure 2(A) is a cross-sectional view taken along the line AA in Figure 1(B), and Figure 2(B) is a cross-sectional view taken along the line BB in Figure 1(B).

[0014] As shown in Figure 1(A), butterfly valve 1 is configured by integrally assembling a body 2 that houses a valve portion and an actuator 4 that drives the valve portion. Note that a DC motor, stepping motor, or other electric actuator can be used as actuator 4, but detailed explanations of these will be omitted.

[0015] As shown in Fig. 1(B), the butterfly valve 1 includes a valve element 12 that is housed in a body 2 and can open and close a refrigerant passage 10, and a shaft 14 that serves as the center of rotation of the valve element 12. The shaft 14 is connected to a rotation mechanism (rotation axis) of the actuator 4. In this embodiment, the body 2 is obtained by injection molding of a resin material.

[0016] The body 2 has a partition wall 18 that separates the passage 10 from an operating chamber 16 in which the mechanism of the actuator 4 is disposed. An insertion hole 20 for inserting the shaft 14 is provided so as to pass through the partition wall 18. The body 2 also has a bearing hole 22 that faces the insertion hole 20 across the passage 10. The bearing hole 22 is formed coaxially with the insertion hole 20 and supports the lower end of the shaft 14. In other words, the shaft 14 extends radially across the passage 10 and is supported by the body 2 so as to be rotatable about its own axis.

[0017] The insertion hole 20 is a stepped hole, with a large diameter portion 23 and a small diameter portion 24 connected from the upper step. A flange portion 15 extending radially outward is provided on the upper part of the shaft 14, and the flange portion 15 is slidably inserted into the large diameter portion 23. In other words, the shaft 14 rotates about its axis while being supported at two points, the large diameter portion 23 and the bearing hole 22. A sealing O-ring 26 is disposed in the step portion 25 formed at the boundary between the large diameter portion 23 and the small diameter portion 24. By interposing the O-ring 26 between the step portion 25 and the flange portion 15, leakage of refrigerant from the passage 10 side to the working chamber 16 side is restricted.

[0018] As shown in FIG. 2(A), the body 2 has a T-shaped cross section, and the passage 10 is a T-shaped passage. That is, the passage 10 has a linear first passage 30 that penetrates the body 2 and a second passage 32 that is connected to the first passage 30 at a right angle. One end of the second passage 32 is provided with an inlet port 34 for introducing refrigerant from the upstream side. Meanwhile, one end of the first passage 30 is provided with a first outlet port 36, and the other end is provided with a second outlet port 38. The valve element 12 is disposed at a connection point of the first passage 30 with the second passage 32. The refrigerant introduced via the inlet port 34 is discharged downstream from the first outlet port 36 or the second outlet port 38, depending on the rotational position of the valve element 12.

[0019] 2(B), the valve element 12 is not fixed to the shaft 14 in the axial direction, and its movement in the axial direction is restricted by the inner surface of the passage 10. That is, a pair of flat surfaces 40, 42 are formed by cutting on the inner wall surfaces of the passage 10 that face the upper and lower end surfaces of the valve element 12, respectively, and these flat surfaces restrict the movement of the valve element 12 in the axial direction.

[0020] 2(A), its outer periphery abuts against the inner periphery of the passage 10. This closes the passage on the first outlet port 36 side or the passage on the second outlet port 38 side, achieving a seal in the closed state (valve closed state). That is, the valve disc 12 is rotatable in one direction (counterclockwise in the figure) or the opposite direction (clockwise in the figure) about the axis L of the shaft 14 (see dotted and dashed lines in the figure), and is rotationally driven by the actuator 4.

[0021] Rotating the valve element 12 in one direction closes the first valve (dotted line state in the figure), opens the first flow path connecting the inlet port 34 and the first outlet port 36, and closes (blocks) the second flow path connecting the inlet port 34 and the second outlet port 38. Rotating the valve element 12 in the other direction closes the second valve (broken line state in the figure), opens the second flow path, and closes (blocks) the first flow path. In this way, the open / closed state of the valve is switched depending on the rotation direction of the valve element 12, and the flow paths within the body 2 can be switched. When opening or closing either the first valve or the second valve, the valve element 12 is attached to or detached from the inner surface of the second passage 32 so as to form an angle of less than 90 degrees with respect to the axis Ly of the second passage 32.

[0022] 3A and 3B are perspective views showing the structure of the body, in which Fig. 3A shows a front view and Fig. 3B shows a longitudinal cross section along the axis of the second passage 32. The passage 10 of the body 2 has a cylindrical side surface 44 parallel to the axis Lx of the first passage 30, a cylindrical side surface 46 parallel to the axis Ly of the second passage 32, and a spherical sealing surface 48 at the point where the first passage 30 and the second passage 32 intersect.

[0023] The "spherical surface" referred to here may be an ellipsoidal spherical surface, and the "spherical shape" may be a concave curved surface that forms an arc centered on the axis L of the shaft 14 in a cross section perpendicular to the axis L of the shaft 14. The sealing surface 48 has a curved shape that is complementary to the outer peripheral surface (sealing portion) of the valve body 12. It is formed at the tip end in the depth direction of the second passage 32 in the body 2 (i.e., the side surface of the first passage 30 against which the second passage 32 abuts). The sealing surface 48 is obtained by injection molding by inserting a mandrel with a spherical tip into a predetermined mold from the introduction port 34 side.

[0024] Next, the configuration of the valve body 12 will be described in detail. Figure 4 shows the structure of the valve body 12. Figure 4(A) is a perspective view, Figure 4(B) is a plan view, Figure 4(C) is a left side view, and Figure 4(D) is a right side view. Figure 4(E) is a cross-sectional view taken along the arrow CC in Figure 4(B), and Figure 4(F) is a cross-sectional view taken along the arrow DD in Figure 4(E).

[0025] The valve body 12 is obtained by covering the outer surface of a metal body 50 with an elastic member 52, and is elliptical or oval in front view and Y-shaped in plan view (Figs. 4(A), (B), and (F)). The valve body 12 is symmetrical about a center line L1 perpendicular to the axis L in plan view, and about a center line L2 in the vertical direction in front view (Figs. 4(B) and (E)).

[0026] The main body 50 has a cylindrical base portion 54 through which the shaft 14 is inserted, a plate-shaped first main body portion 56 extending radially outward from the base portion 54, and a bifurcated second main body portion 58 extending from the base portion 54 on the opposite side to the first main body portion 56. The main body 50 can be formed by metal injection molding (such as metal powder injection molding), forging, die casting, or the like. The base portion 54 is provided with a mounting hole 55 that passes through the main body 50 in the axial direction, and the shaft 14 is assembled so as to pass through the mounting hole 55 (see FIG. 2(B)).

[0027] The second main body portion 58 includes a first plate 60 branching off to one side of the center line L1, and a second plate 62 branching off to the other side. The first plate 60 is covered with the elastic member 52 to form a first valve body portion 64, and the second plate 62 is covered with the elastic member 52 to form a second valve body portion 66. The first main body portion 56 is covered with the elastic member 52 to form a third valve body portion 68. Beads are protruded along the outer circumferential surface of each valve body portion.

[0028] That is, a bead 65 protrudes so as to draw an arc along the outer peripheral surface of the first valve body portion 64. A bead 67 protrudes so as to draw an arc along the outer peripheral surface of the second valve body portion 66. A bead 69 protrudes so as to draw an arc along the outer peripheral surface of the third valve body portion 68. The bead 65 functions as the "first bead portion," the bead 67 functions as the "second bead portion," and the bead 69 functions as the "third bead portion."

[0029] In a cross section of the valve body 12, the distance r1 from the axis L of the shaft 14 to the beads 65, 67 is greater than the distance r2 from the axis L to the bead 69 (FIG. 4(F)). As a result, the bead 69 is seated on the side surface 44 (seal surface 48) of the first passage 30, the side surface of the second passage 32, and the beads 65, 67 are configured to be seated on the side surface of the second passage 32 (see FIG. 2(A)).

[0030] In the manufacturing process of the valve body 12, the elastic member 52 (a corrosion-resistant resin material) is baked onto the main body 50. In this embodiment, rubber is used as the elastic member 52, and the rubber and the main body 50 are vulcanized and joined together. This allows the elastic member 52 to be stably fixed to the main body 50 in a tight contact state.

[0031] The shaft 14 is provided with a so-called D-cut at the portion that is inserted into the valve body 12. That is, a pair of flat surfaces is formed at the portion of the shaft 14 that is inserted into the mounting hole 55, and these flat surfaces constitute a rotational force transmission surface 70 for transmitting the rotational force of the actuator 4 (FIG. 4(F)).

[0032] Meanwhile, a pair of pressure-receiving surfaces 72 that respectively come into contact with the pair of rotational force transmission surfaces 70 are formed on the inner wall surface of the base portion 54. When the actuator 4 is driven to rotate the shaft 14, the rotational force transmission surfaces 70 press against the pressure-receiving surfaces 72, thereby applying a rotational torque to the main body 50. The valve element 12 rotates in a direction corresponding to the rotation of the actuator 4 to adjust the open / closed state of the passage 10.

[0033] The upper and lower end surfaces of the elastic member 52 are flat surfaces 74, 76 that are perpendicular to the axis L and parallel to each other (FIGS. 4(A) to 4(F)). A circular annular bead 78 protrudes from the flat surface 74 so as to surround the upper opening of the mounting hole 55. The annular bead 78 coaxially surrounds the opening of the insertion hole 20 and is in close contact with the flat surface 40, preventing the refrigerant from flowing into the valve body 12 (see FIG. 1(B)). Meanwhile, a circular annular bead 80 protrudes from the flat surface 76 so as to surround the lower opening of the mounting hole 55. The annular bead 80 coaxially surrounds the opening of the bearing hole 22 and is in close contact with the flat surface 42, preventing the refrigerant from flowing into the valve body 12 (see FIG. 1(B)).

[0034] Furthermore, a pair of straight beads 82, 84 are provided on the upper surface of the elastic member 52 so as to extend radially outward from the annular bead 78 (FIG. 4(B)). An arc-shaped bead 86 is provided so as to be perpendicular to the tip of the straight bead 82. One end of the arc-shaped bead 86 is connected to one end of the bead 65, and the other end of the arc-shaped bead 86 is connected to one end of the bead 67. Furthermore, one end of the bead 69 is connected to the tip of the straight bead 84.

[0035] Similarly, a pair of straight beads 88, 90 are provided on the underside of the elastic member 52 so as to extend radially outward from the annular bead 80 (FIG. 4(E)). An arc-shaped bead 92 is provided so as to be perpendicular to the tip of the straight bead 88. One end of the arc-shaped bead 92 is connected to the other end of the bead 65, and the other end of the arc-shaped bead 92 is connected to the other end of the bead 67. Furthermore, the other end of the bead 69 is connected to the tip of the straight bead 90.

[0036] Arc-shaped bead 86 is arranged concentrically with annular bead 78, and arc-shaped bead 92 is arranged concentrically with annular bead 80. Note that, although "concentric" here preferably refers to a circular arc, when the arc-shaped bead is short as shown in the figure, it may also be linear (extending in the tangential direction of the concentric circles of the annular seal portion). Such a linear shape may be substantially included in the concept of "concentric."

[0037] The annular bead 78, the straight beads 82 and 84, and the arcuate bead 86 adhere to the flat surface 40 of the passage 10 with substantially the same crushing margin regardless of whether the valve portion is open or closed. Similarly, the annular bead 80, the straight beads 88 and 90, and the arcuate bead 92 adhere to the flat surface 42 of the passage 10 with substantially the same crushing margin regardless of whether the valve portion is open or closed.

[0038] Figure 5 is a diagram showing the opening and closing operation of the valve body 12. Figure 5(A) shows the neutral state, Figure 5(B) shows the state in which the first flow path is open, and Figure 5(C) shows the state in which the second flow path is open. In the neutral state, the bead 69 remains in close contact with the sealing surface 48 (sealed state), but the beads 65 and 67 are separated from the side surface 46 of the second passage 32 (FIG. 5(A)). Because both the first valve and the second valve are open, both the first flow path f1 and the second flow path f2 are open. At this time, the ratio of the flow rates of the first flow path f1 and the second flow path f2 can be adjusted by adjusting the rotation angle of the valve body 12.

[0039] By rotating the valve element 12 in one direction (clockwise in the figure), the bead 69 slides while remaining in close contact with the seal surface 48, and the bead 65 seats on the side surface 46 of the second passage 32 (FIG. 5(B)). The bead 65 functions as the "first seal portion," and the bead 69 functions as the "second seal portion." As a result, the first valve closes, blocking the second flow path f2. The second valve is fully open, and the first flow path f1 is opened. At this time, a continuous annular seal structure is realized in the order of annular bead 78 → straight bead 82 → arc-shaped bead 86 → bead 65 → arc-shaped bead 92 → straight bead 88 → annular bead 80 → straight bead 90 → bead 69 → straight bead 84 → annular bead 78 (see FIG. 4), ensuring the sealing state of the first valve. The bead 67 is detached from the side surface 46 of the second passage 32.

[0040] On the other hand, by rotating the valve element 12 in the other direction (counterclockwise in the figure), the bead 69 slides while remaining in close contact with the seal surface 48, and the bead 67 seats on the side surface 46 of the second passage 32 (FIG. 5(C)). The bead 67 functions as the "first seal portion," and the bead 69 functions as the "second seal portion." As a result, the second valve closes, blocking the first flow path f1. The first valve is fully open, and the second flow path f2 is opened. At this time, a continuous annular seal structure is realized in the order of annular bead 78 → straight bead 82 → arc-shaped bead 86 → bead 67 → arc-shaped bead 92 → straight bead 88 → annular bead 80 → straight bead 90 → bead 69 → straight bead 84 → annular bead 78 (see FIG. 4), ensuring the sealing state of the second valve. The bead 65 is detached from the side surface 46 of the second passage 32.

[0041] 6A and 6B are diagrams showing the effects of the seal structure of the embodiment. Fig. 6A shows the effects of the embodiment, and Fig. 6B shows the effects of a comparative example. The comparative example differs from the embodiment in that it does not have a spherical seal surface at the intersection of the first passage and the second passage.

[0042] As described above, in this embodiment, a spherical seal surface 48 is provided at the intersection between the first passage 30 and the second passage 32 (FIG. 6(A)). During valve closing, as the first seal portion S1 (beads 65, 67) seats on the side surface 46 of the second passage 32, the second seal portion S2 (bead 69) slides along the seal surface 48. That is, the first seal portion S1 achieves sealing by seating, so the sealing position is physically limited. In contrast, the second seal portion S2 maintains its sealing state during the sliding process, so its sealing position can change depending on the seating position of the first seal portion S1. Therefore, even if the position of the axis L deviates from its original position (error Δs) due to an assembly error of the butterfly valve or the like, causing the sealing position of the first seal portion S1 to deviate slightly, the second seal portion S2 can move to follow the deviation and maintain the sealing state.

[0043] In contrast, in the comparative example, sealing is achieved by both the first seal portion S1 and the second seal portion S2 seating on the side surface 144 of the passage 130. Therefore, if the position of the axis L deviates from its original position (error Δs), even if one of the first seal portion S1 and the second seal portion S2 can seat on the side surface 144, the other cannot, resulting in a gap Δc. As a result, a sealed state cannot be achieved. In other words, according to this embodiment, it is easier to flexibly respond to the assembly accuracy of the butterfly valve than the comparative example.

[0044] As described above, according to this embodiment, even if the sealing position of the first seal portion S1 is limited, the sealing position of the second seal portion S2 has an adjustable range. This allows for some degree of tolerance for imprecise assembly of the butterfly valve, ensuring sealing performance. Therefore, there is no need to increase the rotational load of the actuator and increase the crushing margin of the seal portion to ensure sealing performance. Furthermore, in this embodiment, the valve element 12 is shaped (Y-shaped) so that one side of the valve element 12 expands radially, branching the first seal portion S1 into two, separating the first and second bead portions in the direction of rotation of the valve element 12. This reduces the rotation angle of the valve element 12 when switching between the sealing states of the respective bead portions. This means that the time required to switch between the open and closed states of the first and second valves can be shortened.

[0045] [Variations] 7A and 7B are diagrams showing the structure of a valve body according to a modified example, in which Fig. 7A is a perspective view, Fig. 7B is a plan view, Fig. 7C is a left side view, and Fig. 7D is a right side view. This modified example differs from the above embodiment in that the valve body 112 does not have a bifurcated structure. The valve body 112 has a valve body portion 164 that is fan-shaped in a plan view and fills the gap between the first valve body portion 64 and the second valve body portion 66 shown in Figure 4. Beads 65, 67 protrude from the valve body portion 164, drawing an arc along the outer circumferential surface. The positions of the beads 65, 67 are the same as in the above embodiment.

[0046] This modification also provides sealing performance similar to that of the above embodiment with a seal structure including the first seal portion S1 and the second seal portion S2. Although the material yield of the valve body 112 is lower than that of the above embodiment, the structure can be simplified because it does not have a bifurcated shape.

[0047] In this modified example, the valve body portion 164 and the third valve body portion 68 are asymmetrical with respect to the axis L of the valve body 112, but in other modified examples, the outer shapes may be symmetrical except for the bead portion. Even with such a structure, sealing performance can be ensured as long as the bifurcated structure that branches into the first bead portion S1 and the second bead portion S2 is maintained.

[0048] [Second embodiment] Figure 8 shows the configuration of a butterfly valve according to a second embodiment. Figure 8(A) is a cross-sectional view corresponding to Figure 2(A) of the first embodiment. Figure 8(B) is a cross-sectional view taken along the line EE in Figure 8(A).

[0049] The butterfly valve of this embodiment differs from that of the first embodiment in that it functions as a four-way valve. 8(A), the body 202 has a cross-shaped passage 210. That is, the passage 210 has a first linear passage 230 that penetrates the body 202 and a second linear passage 232 that also penetrates the body 202, the first linear passage 230 and the second linear passage 232 intersecting each other at right angles. One end of the second passage 232 is provided with an inlet port 234 for introducing a refrigerant from the upstream side, and the other end is provided with an outlet port 235 for discharging the refrigerant to the downstream side. Meanwhile, one end of the first passage 230 is provided with a first inlet / outlet port 236 for introducing or discharging a refrigerant, and the other end is provided with a second inlet / outlet port 238 for introducing or discharging a refrigerant.

[0050] The valve element 12 is disposed at the connection point between the first passage 230 and the second passage 232. The outlet port 235 has a communication hole 237 formed in a side surface 44 of the first passage 230. The communication hole 237 has a smaller opening area than the inlet port 234. The seal surface 48 is provided on the side surface 44 of the first passage 230 on the outlet port 235 side. As shown in FIG. 8(B) , the communication hole 237 has an elliptical shape in a plan view and penetrates the inside of the seal surface 48. In other words, the second passage 232 is narrowed at the position of the communication hole 237, and the seal surface 48 is formed to surround the communication hole 237. This ensures a sufficient area for the seal surface 48.

[0051] Figure 9 is a diagram showing the opening and closing operation of the valve body 12. Figure 9(A) shows the neutral state, Figure 9(B) shows the state in which the first flow path and the second flow path are open, and Figure 9(C) shows the state in which the third flow path and the fourth flow path are open. In the neutral state, the bead 69 is separated from the seal surface 48, and the beads 65, 67 are separated from the side surface 46 of the second passage 32 (FIG. 9(A)). Because both the first valve and the second valve are open, the refrigerant introduced from the inlet port 234 is discharged from the outlet port 235, the first inlet / outlet port 236, and the second inlet / outlet port 238, respectively.

[0052] By rotating the valve element 12 in one direction (clockwise in the figure), the bead 69 slides while adhering closely to the seal surface 48, and the bead 65 seats on the side surface 46 of the second passage 232 (FIG. 9(B)). The bead 65 functions as the first seal portion S1, and the bead 69 functions as the second seal portion S2. As a result, the first valve closes and the second valve is fully open, forming a first flow path f1 and a second flow path f2. The refrigerant introduced from the inlet port 234 is discharged from the first inlet / outlet port 236, and the refrigerant introduced from the second inlet / outlet port 238 is discharged from the outlet port 235.

[0053] On the other hand, by rotating the valve element 12 in the other direction (counterclockwise in the figure), the bead 69 slides while adhering closely to the seal surface 48, and the bead 67 seats on the side surface 46 of the second passage 232 (FIG. 9(C)). The bead 67 functions as the first seal portion S1, and the bead 69 functions as the second seal portion S2. As a result, the second valve closes and the first valve is fully opened, forming the third flow path f3 and the fourth flow path f4. In other words, the flow paths are switched. The refrigerant introduced from the inlet port 234 is discharged from the second inlet / outlet port 238, and the refrigerant introduced from the first inlet / outlet port 236 is discharged from the outlet port 235.

[0054] In this embodiment, the seal structure including the first seal portion S1 and the second seal portion S2 provides the same sealing performance as in the first embodiment. Note that although the present embodiment employs the same valve body 12 as in the first embodiment, a modified valve body 112 (FIG. 7) may also be employed.

[0055] [Third embodiment] Figure 10 is a diagram showing the configuration of a butterfly valve according to a third embodiment. Figure 10(A) is a cross-sectional view corresponding to Figure 2(A) of the first embodiment. Figure 10(B) is a cross-sectional view taken along the line EE in Figure 10(A).

[0056] The butterfly valve of this embodiment differs from the first embodiment in that it functions as a two-way valve. As shown in Fig. 10(A), the body 302 has a passage 310 with an L-shaped axis. That is, the passage 310 has a first passage 330 and a second passage 332 that intersect at right angles. The second passage 332 is provided with an inlet port 334 for introducing a refrigerant from the upstream side, and the first passage 330 is provided with an outlet port 336 for discharging the refrigerant to the downstream side.

[0057] The valve element 12 is disposed at the connection point between the first passage 330 and the second passage 332. The sealing surface 48 is formed at the tip of the second passage 332 in the depth direction of the body 302 (on the side surface of the tip of the first passage 330). As also shown in Fig. 10(B) , the side surface of the corner where the first passage 330 and the second passage 332 intersect is formed in a spherical shape.

[0058] Figure 11 is a diagram showing the opening and closing operation of the valve element 12. Figure 11(A) shows the open state, and Figure 11(B) shows the closed state. By rotating the valve element 12 in one direction (clockwise in the figure), the bead 69 slides while adhering closely to the seal surface 48, and the bead 65 seats on the side surface 46 of the second passage 332 (FIG. 10(A)). The bead 65 functions as the first seal portion S1, and the bead 69 functions as the second seal portion S2. As a result, the valve portion is fully opened, and the flow path f is opened. The refrigerant introduced from the inlet port 334 is discharged from the first inlet / outlet port 336.

[0059] On the other hand, by rotating the valve element 12 in the other direction (counterclockwise in the figure), the bead 69 slides while adhering closely to the seal surface 48, and the bead 67 seats on the side surface 46 of the second passage 332 (FIG. 10(B)). The bead 67 functions as the first seal portion S1, and the bead 69 functions as the second seal portion S2. As a result, the valve portion closes and the flow path f is blocked.

[0060] In this embodiment, the seal structure including the first seal portion S1 and the second seal portion S2 provides the same sealing performance as in the first embodiment. Note that although the present embodiment employs the same valve body 12 as in the first embodiment, a modified valve body 112 (FIG. 7) may also be employed.

[0061] Although the preferred embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to this specific embodiment, and various modifications are possible within the scope of the technical concept of the present invention.

[0062] [Variations] In the above embodiment, the butterfly valve body is formed by injection molding a resin material. In a modified example, the body may be formed by cutting a metal material such as an aluminum alloy or brass. For cutting the flat surface, a machining center or an internal broach may be used.

[0063] In the above embodiment, a bead is provided as a protruding seal on the elastic member covering the plate. In this modified example, the bead may be formed by cutting out a groove in the surface of the elastic member that constitutes the valve body, leaving a remaining portion.

[0064] Alternatively, the bead-less structure may be used, with the portion that functions as the sealing portion being set at a different position on the elastic member. However, from the viewpoint of keeping the closing torque of the valve body small, it is preferable to use a bead-shaped sealing portion.

[0065] In the above embodiment, the angle of the valve disc relative to the axis of the passage when the valve is closed is set to approximately 45 degrees, and the valve disc seals the passage at an angle. In a modified example, the angle of the valve disc may be any other appropriate angle less than 90 degrees.

[0066] Although not mentioned in the above embodiment and modified example, the shaft may not penetrate the valve body. Specifically, in the configuration shown in Fig. 1(B), the tip of the shaft 14 may remain inside the valve body 12. In this case, the bearing hole 22 can be omitted.

[0067] In the above embodiment, an example in which the butterfly valve is applied to the refrigeration cycle of a vehicle air conditioner has been shown. In a modified example, the butterfly valve may be applied to the refrigeration cycle of other air conditioners, such as those for home use. Alternatively, the butterfly valve may be applied to a circulation circuit of a coolant (coolant water or cooling oil) for an automobile used to cool a battery or motor. That is, the butterfly valve may be applied to a fluid circuit in an automobile fluid control system. Alternatively, the butterfly valve may be applied to a water circuit in a hot water supply system or the like. Furthermore, the butterfly valve may be applied to a device that controls the flow of oil or other working fluids.

[0068] The present invention is not limited to the above-described embodiments and modifications, and the components can be modified without departing from the spirit of the invention. Various inventions can be formed by appropriately combining multiple components disclosed in the above-described embodiments and modifications. Furthermore, some components can be omitted from all the components shown in the above-described embodiments and modifications. [Explanation of symbols]

[0069] 1 butterfly valve, 2 body, 4 actuator, 10 passage, 12 valve body, 14 shaft, 20 insertion hole, 22 bearing hole, 26 O-ring, 30 first passage, 32 second passage, 34 inlet port, 36 first outlet port, 38 second outlet port, 44 side surface, 46 side surface, 48 sealing surface, 50 main body, 52 elastic member, 60 first plate, 62 second plate, 64 first valve body portion, 65 bead, 66 second valve body portion, 67 bead, 68 third valve body portion, 69 bead, 76 flat surface, 78 annular bead, 80 annular bead, 82 straight bead, 84 straight bead, 86 arc-shaped bead, 88 straight bead, 90 straight bead, 92 arc-shaped bead, 112 valve body, 164 valve body portion, 202 Body, 210 passage, 230 first passage, 232 second passage, 234 inlet port, 235 outlet port, 236 first inlet / outlet port, 237 communication hole, 238 second inlet / outlet port, 302 body, 310 passage, 330 first passage, 332 second passage, 334 inlet port, 336 outlet port, 336 first inlet / outlet port, S1 first seal portion, S2 second seal portion, f flow path, f1 first flow path, f2 second flow path, f3 third flow path, f4 fourth flow path.

Claims

1. An electrically operated butterfly valve, a body having a passageway for passing a fluid; a shaft supported by the body so as to be rotatable about its own axis and extending in a radial direction of the passage; a valve body that is disposed in the passage while being assembled to the shaft and that can open and close the passage by rotating together with the shaft; an actuator that rotates the shaft when energized; Equipped with the valve body has a seal portion on its outer periphery that is detachably attached to the inner surface of the passage to open and close the passage; the passage includes a first passage and a second passage, and has a spherical sealing surface at a location where the first passage and the second passage intersect; The sealing portion is a first seal portion that is detachably attached to a cylindrical side surface of the second passage and that is seated on the side surface to lock the valve body in the rotational direction; a second seal portion that is slidable while in close contact with the seal surface; A butterfly valve comprising:

2. 2. The butterfly valve according to claim 1, wherein the first seal portion and the second seal portion are bead portions that protrude toward the inner surface of the passage and extend along the outer periphery.

3. the first seal portion includes a first bead portion that seats in the second passage when the shaft rotates in one direction, and a second bead portion that seats in the second passage when the shaft rotates in the opposite direction; 3. The butterfly valve according to claim 2, wherein the second seal portion includes a single third bead portion that can abut along the seal surface.

4. 4. A butterfly valve according to claim 1, wherein in a cross section of the valve body, the distance from the axis of the shaft to the first seal portion is greater than the distance from the axis of the shaft to the second seal portion.

5. 4. The butterfly valve according to claim 1, wherein the sealing surface is formed at a tip end portion of the second passage in the body in a depth direction.

6. the second passage extends through the interior of the sealing surface; 4. The butterfly valve according to claim 1, wherein a passage width of the second passage on the second seal portion side is smaller than a passage width of the second passage on the first seal portion side.

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