Diverter valve

Abstract

Provided is a diverter valve in which the number of components is reduced to lower cost, interference of the packing of a valve body during rotation of the valve body is suppressed by providing a taper on the peripheral surface of the opening of each port, and the pressure loss due to the valve body is also suppressed. In the diverter valve, the opening of each port is provided in the side surface of a valve chamber 11 in which a valve body 15 is rotatably installed, the valve body 15 rotating to open and close the opening of each port to thereby switch the flow passage. An arcuately curved valve portion 15k of the valve body 15 that closes the opening of each port is limited to a size sufficient to cover the opening of each port. A packing 19 is provided to seal the opening of each port, and a taper is provided along the sliding direction of rotation of the valve body 15 at a connection portion between the opening of each port and the valve chamber 11.

Description

Flow path switching valve

[0001] The technology disclosed in the present application relates to a flow path switching valve that switches a flow path of a fluid.

[0002] Ball valve-type flow path switching valves have traditionally been used as flow path switching valves such as three-way valves. In ball valve-type flow path switching valves, as shown in the ball valve-type three-way valve 300 shown in Fig. 9, for example, sealing members 306 and 307 such as packings or O-rings 308, 309, 310, and 311 are generally interposed between openings 302 and 303 of each port provided in a valve chamber 304 in a body 301 and a ball valve 305 to seal between the openings 302 and 303 of each port and the ball valve 305.

[0003] Patent Document 1 also discloses a flow path switching valve in which the valve element has been changed from a ball valve to a swing valve. The swing valve has a face plate that is approximately square in shape from the front and has an arcuate cross section, and a valve disk made of synthetic rubber and having a circular shape from the front is embedded in the face plate, and this valve disk seals the gap between the swing valve and each outlet.

[0004] Furthermore, Patent Document 2 discloses a three-way valve comprising a valve disc having a retaining member fitted with an arch-shaped elastic body, a valve body having a semi-cylindrical valve chamber in which the valve disc is rotatably housed, a rotary shaft for rotating and sliding the valve disc within the valve chamber, a coil spring for urging the elastic body of the valve disc against the inner surface of the valve chamber, and an inlet pipe and two outlet pipes connected to the valve disc.

[0005] Patent No. 7032848 Patent No. 5982101

[0006] The conventional ball valve type three-way valve shown in FIG. 9 requires sealing members 306, 307 such as packing, O-rings 308, 309, 310, 311 that seal between the sealing members 306, 307 and the openings 302, 303 or the body 301, and joints 312, 313 that support the sealing members 306, 307, which increases the number of parts and tends to increase costs.

[0007] Furthermore, in the flow path switching valve disclosed in Patent Document 1, the connection between each outlet and the casing peripheral side wall is at an acute angle, which causes a problem in that when the swing valve rotates and passes through each outlet, this acute angle interferes with the valve disc made of synthetic rubber, making the valve disc prone to damage.

[0008] Furthermore, in the three-way valve disclosed in Patent Document 2, similar to Patent Document 1, the connection between the outlet port and the valve chamber side wall forms an acute angle, which causes problems such as the elastic body attached to the valve body interfering with the acute angle and becoming worn when the valve disc rotates to close one of the outlet ports, and also causes problems such as the arch-shaped valve disc obstructing the flow path and resulting in large pressure loss.

[0009] The technology disclosed in this application has been proposed in view of the above-mentioned problems, and aims to provide a flow path switching valve that reduces costs by reducing the number of parts, and that provides a tapered circumferential surface of the opening of each port to prevent interference with the packing of the valve body when the valve body rotates, and that also prevents pressure loss due to the valve body.

[0010] In order to achieve the above object, a flow path switching valve according to claim 1 comprises a cylindrical valve chamber, at least three ports communicating with a side surface of the valve chamber, a valve element that rotates within the valve chamber, and a drive unit that rotates the valve element, and the drive unit rotates the valve element within the valve chamber to communicate at least two of the at least three ports to switch flow paths, and the valve element has a surface size that is limited along the side surface of the valve chamber to an extent that it covers the openings of at least three ports, and the valve element has a valve element main body that has a curved arc shape that follows the curve of the cylindrical side surface of the valve chamber, a disk-shaped upper surface provided around a rotation axis connected to the drive unit, and the valve chamber and a disk-shaped underside having a cylindrical recess at its center that fits into a cylindrical protrusion at the center of the bottom of the valve chamber, and a packing made of an elastic member having an arc-shaped protrusion at its center that faces the side of the valve chamber is attached to the valve body on the side of the valve body so as to surround the periphery of any one of the openings of at least three ports, and further characterized in that a taper is provided at the connection between the opening of at least one of the at least three ports provided on the side of the valve chamber and the side of the valve chamber, which tapers over the outer circumferential surface of the opening of at least one port to prevent interference of the packing of the valve body when the valve body rotates.

[0011] In the flow path switching valve according to claim 1, by attaching a packing to the valve disc, the attached packing seals the opening when the valve disc rotates to close the opening of the port, so there is no need to incorporate sealing members such as packing, rings, or joints to support the sealing members as in conventional ball valve-type three-way valves, reducing the number of parts and lowering costs. Also, by providing an arc-shaped protrusion on the packing attached to the side of the valve disc, it is possible to completely close the opening of either port when it is closed.

[0012] Furthermore, a taper is provided around the outer periphery of the connection between the opening of each port and the side surface of the valve chamber to prevent the packing on the valve body from interfering when the valve element rotates. This allows the valve element to rotate and pass through the opening of each port without interfering with the connection, thereby preventing wear on the packing.

[0013] Furthermore, by limiting the size of the curved valve body to a size that covers the openings of at least three ports, the valve body does not obstruct the flow path when the openings of at least two ports are fully opened and connected, and pressure loss can be kept within the flow path diameter.

[0014] 1A and 1B are external views of a flow path switching valve according to an embodiment of the present invention, including (A) a front view, (B) a side view of the front view as seen from the right, and (C) a bottom view. (A) A cross-sectional view taken along line A-A in FIG. 1, and (B) a cross-sectional view taken along line B-B in FIG. 1. (A) A front view of a valve body according to the present invention, (B) a side view of the front view as seen from the right, (C) a top view of the side view as seen from above, and (D) a bottom view of the side view as seen from below. (A) A cross-sectional view taken along line C-C in FIG. 3, (B) a cross-sectional view taken along line D-D in FIG. 3, and (C) a cross-sectional view taken along line E-E in FIG. 3. (A) A front view, (B) a top view, (C) a bottom view, (D) a side view of the front view as seen from the right, (E) a cross-sectional view taken along line F-F in (A), and (F) a cross-sectional view taken along line G-G in (A), of a packing according to the present invention. (F) A cross-sectional view illustrating the attachment of a packing to a valve body. (F) A cross-sectional view illustrating the operation of a flow path switching valve according to an embodiment of the present invention. 1 is a diagram illustrating a taper provided at the opening of each port. 2 is a diagram illustrating a conventional ball valve type flow path switching valve.

[0015] First, a flow path switching valve 1 according to one embodiment of the present invention will be described with reference to the drawings. Fig. 1 is an external view of the flow path switching valve 1 according to one embodiment of the present invention. Fig. 1A is a front view, Fig. 1B is a side view of the front view as seen from the right, and Fig. 1C is a bottom view.

[0016] As shown in FIG. 1 , flow path switching valve 1 is composed of a body 2 having a first port 3, a second port 4, and a third port 5 connected to each flow path, a drive unit 6 including a stepping motor or the like that rotates a valve element within body 2, and a body lid 7 that covers the top of body 2 in the drawing and is interposed between body 2 and drive unit 6. Drive unit 6 is attached to body 2 via body lid 7 with mounting screws 8 (one of which is not shown). Body 2 is provided with first port 3 and second port 4 that are arranged facing each other on the same axis, and third port 5 that is arranged perpendicular to the axis connecting first port 3 and second port 4. First port 3, second port 4, and third port 5 are arranged on the same plane, and drive unit 6 is arranged above first port 3, second port 4, and third port 5 in the drawing via body lid 7.

[0017] 2A is a cross-sectional view taken along line A-A in FIG. 1, and FIG. 2B is a cross-sectional view taken along line B-B in FIG. 1. As shown in FIG. 2, a cylindrical valve chamber 11 is provided in the center of the body 2, in which a valve element 15 is rotatably disposed. As described above, the side surface of the valve chamber 11 is provided with the first port 3 having the first flow path 8 therein, the second port 4 facing the first port 3 across the valve chamber 11 and having the second flow path 9 therein and coaxial with the first port 3, and the third port 5 having the third flow path 10 therein in a direction perpendicular to the axis connecting the first port 3 and the second port 4. The side surface of the valve chamber 11 is provided with a first opening 12 that opens to the first flow path 8 of the first port 3, a second opening 13 that opens to the second flow path 9 of the second port 4, and a third opening 14 that opens to the third flow path 10 of the third port 5. The valve body 15 rotates to close one of the openings, thereby switching the flow path.

[0018] A pivot shaft 15a is provided at the top of the valve disc 15, and the upper part of the pivot shaft 15a is inserted into the drive unit 6 via the body cover 7. The pivot shaft 15a is controlled to rotate by a stepping motor or the like in the drive unit 6, thereby controlling the rotation of the valve disc 15 within the valve chamber 11. O-rings 17 and 18 are attached between the pivot shaft 15a and the body cover 7, maintaining a seal between the pivot shaft 15a and the body cover 7. An O-ring 16 is attached between the body cover 7 and the body 2, maintaining a seal between the body cover 7 and the body 2. These O-rings thus maintain a seal between the valve chamber 11 of the body 2 and the outside. A cylindrical valve chamber protrusion 2a is provided at the center of the bottom of the valve chamber 11 of the body 2, and this protrusion 2a fits into a cylindrical valve disc recess 15b provided on the lower end surface of the valve disc 15. This prevents lateral vibration of the valve element 15 when it rotates, and unlike the flow path switching valve of Patent Document 1 and the three-way valve of Patent Document 2, the rotation axis does not pass through the valve element, so the rotation axis 15a of the valve element 15 does not exist inside the valve chamber 11. This prevents the valve element 15 from blocking the flow path. Furthermore, a packing 19 with a protrusion facing the opening on the side of the valve chamber 11 is attached to the side of the valve element 15. When the valve element 15 closes the opening of each port, the protrusion attached to the packing 19 enables complete closure.

[0019] Next, the valve body 15, which is one of the features of the present invention, will be described. Figure 3 is an external view of the valve body 15. In Figure 3, (A) is a front view of the valve body 15, (B) is a side view of the front view seen from the right, (C) is a top view of the side view seen from above, and (D) is a bottom view of the side view seen from below.

[0020] As shown in Figure 3A, the valve disc 15 is primarily composed of a pivot shaft 15a and a valve disc body 15c. More specifically, the pivot shaft 15a is composed of a pivot gear 15d inserted into the drive unit 6 and a shaft body 15e provided with shaft O-ring grooves 15f and 15g. The valve disc body 15c is composed of a disk-shaped upper valve body 15j connected to the pivot shaft 15a, a valve section 15k having a curved arc shape that follows the curve of the cylindrical side surface of the valve chamber that closes the openings of each port, and a disk-shaped lower valve body 15l having the same diameter as the upper valve body 15j and a valve disc recess 15b at its bottom that fits into the cylindrical valve chamber protrusion 2a at the bottom of the valve chamber 11 (described above). The valve section 15k is provided with a packing groove 15h for attaching a packing 19. Figure 4 shows cross sections at various positions to more clearly illustrate the structure of the valve disc 15. Fig. 4(A) is a cross-sectional view taken along CC in Fig. 3, Fig. 4(B) is a cross-sectional view taken along DD in Fig. 3, and Fig. 4(C) is a cross-sectional view taken along EE in Fig. 3. As described above, the pivot shaft 15a of the valve body 15 is configured so that the valve body 15 does not obstruct the flow path.

[0021] Next, we will explain the packing 19 attached to the valve body 15. In Figure 5, (A) is a front view, (B) is a top view, (C) is a bottom view, (D) is a side view of the front view seen from the right, (E) is a cross-sectional view taken along line F-F in (A), and (F) is a cross-sectional view taken along line G-G in (A).

[0022] The packing 19 used in this embodiment is made of ethylene propylene rubber (EPDM), which is an elastic material. The packing 19 is not limited to ethylene propylene rubber, and any elastic material may be used as long as it can seal the openings of the ports (first opening 12, second opening 13, and third opening 14) in a closed state.

[0023] 5(B) and 5(C), the packing 19 is fitted into the packing groove 15h provided in the valve portion 15k of the valve body 15, which has a curved surface, and is therefore composed of a packing base 19a having a curved surface that matches the arc of the valve portion 15k of the valve body 15, and a rectangular protrusion 19b that surrounds the periphery of the packing base 19a. The outer periphery of the packing base 19a has a protrusion that fits into the packing groove 15h of the valve body 15, and by fitting the outer periphery of the packing base 19a of the packing 19 into the packing groove 15h of the valve body 15, the valve body 15 acts as an opening / closing valve for each port opening (first opening 12, second opening 13, third opening 14).

[0024] 6A and 6B are diagrams illustrating the attachment of the packing 19 to the valve body 15. As shown in Fig. 6A, the outer periphery of the packing base 19a of the packing 19 is fitted into the packing groove 15h of the valve body 15, and as shown in Fig. 6B, the valve body 15 and the packing 19 are integrated to function as an on-off valve.

[0025] Next, the operation of the flow path switching valve 1 according to this embodiment will be described with reference to FIG.

[0026] Fig. 7A shows a state in which the first opening 12 of the first port 3 is closed by the valve element 15, thereby communicating the second flow path 9 of the second port 4 and the third flow path 10 of the third port. Fig. 7B shows a state in which the valve element 15 is rotated rightward as indicated by arrow (1) in Fig. 7A, thereby communicating the flow paths of three ports: the first flow path 8 of the first port 3, the second flow path 9 of the second port 4, and the third flow path 10 of the third port. Fig. 7C shows a state in which the valve element 15 is further rotated rightward as indicated by arrow (2) in Fig. 7B, thereby closing the third opening 14 of the third port 5 by the valve element 15, thereby communicating the first flow path 8 of the first port 3 and the second flow path 9 of the second port.

[0027] 7A, the outer periphery of the first opening 12, which is the opening of the first port 3, is sealed with packing 19 attached to the valve body 15, so that the first flow path 8 of the first port 3 is completely closed and the second flow path 9 of the second port 4 and the third flow path 10 of the third port 5 are in communication, while in FIG. 7C, the outer periphery of the third opening 14, which is the opening of the third port 5, is sealed with packing 19 attached to the valve body 15, so that the third flow path 10 of the third port 5 is completely closed and the first flow path 8 of the first port 3 and the second flow path 9 of the second port 4 are in communication. In this way, the flow path switching valve 1 can switch the flow paths. Furthermore, as shown in FIG. 7C , by limiting the size of the valve portion 15k having a curved arc shape of the valve element 15 so that the flow path diameter when the first flow path 8 of the first port 3 and the second flow path 9 of the second port 4 are connected is equal to or greater than the flow path diameter φd of the first flow path 8 and the second flow path 9, the valve element 15 does not obstruct the flow path, and pressure loss can be kept within the flow path diameter.

[0028] 7B, it is also possible to communicate the flow paths of three ports, namely, the flow path 8 of the first port 3, the second flow path 9 of the second port 4, and the third flow path 10 of the third port. In this case, the fluid flowing in from the first port 3 and the fluid flowing in from the third port 5 can be mixed and discharged from the second port 4, so the flow path switching valve 1 can also function as a mixing valve.

[0029] Next, the taper provided at the opening of each port will be described. FIG. 8 is a diagram illustrating the taper provided at the opening of each port. FIG. 8B is an enlarged view of the square area E in FIG. 8A. FIG. 8B shows the first opening 12 of the first port 3 as an example. In the flow path switching valve 1 according to this embodiment, the outer peripheral surface (connecting portion) of the opening of each port connected to the valve chamber 11 is provided with a taper TP along the sliding direction of the rotation of the valve disc 15, as shown in the dashed-line area F in FIG. 8B. This allows the packing 19 attached to the valve disc 15 to rotate and pass through the first opening 12 without interfering with the connecting portion between the first opening 12 of the first port 3 and the valve chamber 11, thereby suppressing wear of the packing 19. In the flow path switching valve 1 according to this embodiment, the first port 3 and the third port 5 are closed by the valve body 15, and therefore, although not shown, the outer peripheral surface (connection portion) of the third opening 14 of the third port 5 is also tapered.

[0030] As described above, the flow path switching valve 1 according to this embodiment employs the valve disc 15 equipped with the packing 19 to seal the port openings, eliminating the need to incorporate sealing members such as packings, rings, and joints for supporting the sealing members as in conventional ball valve-type three-way valves, thereby reducing the number of parts and enabling cost savings. Furthermore, the connection portions between the first opening 12 and the third opening 14 of the first port 3 and the third port 5, which are closed by the valve disc 15, and the side surface of the valve chamber 11 are tapered to prevent the packing 19 attached to the valve disc 15 from interfering with each other when the valve disc 15 rotates around the periphery of each opening. This allows the valve disc 19 to rotate and pass through the openings of the ports without interfering with each connection portion, thereby suppressing wear of the packing 19. Furthermore, by providing the packing 19 attached to the valve portion 15k of the valve element 15 with an arc-shaped protrusion 19b that protrudes around the outer periphery toward the side surface of the valve chamber 11, each port can be completely closed when closed. Furthermore, by limiting the size of the valve portion 15k of the valve element 15, which has an arc-shaped curve, to a size that covers the opening of each port, the valve element 15 does not obstruct the flow path when the flow path is fully opened after switching, and pressure loss can be kept within the flow path diameter. Furthermore, as described above, by controlling the rotation of the valve element 15 to a position intermediate between the first opening 12 and the third opening 14, the three ports can be connected, allowing the valve to function as a mixing valve.

[0031] Here, the flow path switching valve 1 is an example of a flow path switching valve, the valve chamber 11 is an example of a valve chamber, the first port 3, the second port 4, and the third port 5 are examples of ports, the valve body 15 is an example of a valve body, the drive unit 6 is an example of a drive unit, the valve portion 15k is an example of a valve body main body, the packing 19 is an example of a packing, and the taper TP is an example of a taper.

[0032] Although the embodiments of the present invention have been described in detail above, these are merely examples, and the present invention should not be construed in any way as being limited by the specific descriptions in such embodiments. It should be understood that the present invention can be implemented in various forms with various changes, modifications, improvements, etc. made based on the knowledge of those skilled in the art, and that all such embodiments are included within the scope of the present invention as long as they do not deviate from the spirit of the present invention.

[0033] For example, in the flow path switching valve 1 of the above embodiment, a taper is provided at the connection between the valve chamber 11 and the first opening 12 of the first port 3 and the third opening 14 of the third port 5, which are closed, but if the second port is also closed, a taper may also be provided at the connection between the valve chamber 11 and the second opening 13 of the second port 4.

[0034] Furthermore, in the above embodiment, the flow path switching valve 1 is exemplified as a three-way valve having a first port 3, a second port 4, and a third port 5, but the flow path switching valve according to the present invention is not limited to a three-way valve, and can also be used in a four-way valve, a five-way valve, etc.

[0035] 1. Flow path switching valve 2. Body 3. First port 4. Second port 5. Third port 6. Actuator 7. Body cover 8. First flow path 9. Second flow path 10. Third flow path 11. Valve chamber 12. First opening 13. Second opening 14. Third opening 15. Valve element 16, 17, 18. O-ring 19. Packing TP. Tapered

Claims

1. A flow path switching valve comprising: a cylindrical valve chamber; at least three ports communicating with the side surface of said valve chamber; a valve element that rotates within said valve chamber; and a drive unit that drives the valve element to rotate, wherein said drive unit rotates said valve element within said valve chamber to communicate at least two of said at least three ports to switch flow paths, wherein said valve element has a surface size that is limited to cover the openings of any of said at least three ports along the side surface of said valve chamber, and is composed of a valve element main body having a curved arc shape that follows the curve of the cylindrical side surface of said valve chamber, a disk-shaped upper surface provided around a rotation axis that connects to said drive unit, and a disk-shaped lower surface provided around a cylindrical recess that fits into a cylindrical protrusion provided at the center of the bottom of said valve chamber, a packing formed of an elastic member and having an arc-shaped protrusion at its center toward the side surface of the valve chamber, is attached to the valve body on the side surface of the valve disc so as to surround the periphery of any one of the openings of the at least three ports; and further, a taper is provided at a connection between the opening of at least one of the at least three ports provided on the side surface of the valve chest and the side surface of the valve chest, so as to prevent interference of the packing of the valve body when the valve disc rotates over the outer circumferential surface of the opening of the at least one port.

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