High-frequency switch switching three-way valve

Abstract

The utility model relates to a high-frequency on-off switching three-way valve, which comprises a valve body, a valve seat, a valve clack, a valve rod and a valve cover, the valve body is provided with an inlet channel and two outlet channels, and guide positioning devices matched with an upper valve clack and a lower valve clack are respectively arranged in the two outlet channels to realize radial positioning and axial guiding of the upper valve clack and the lower valve clack. The upper valve clack and the lower valve clack are prevented from generating radial displacement under the radial thrust effect of an inlet medium, the sealing specific pressure of an upper sealing pair and a lower sealing pair in the circumferential direction is kept uniform, the sealing performance of the sealing pairs is improved, meanwhile, the radial pressure of the valve rod on the packing sealing device is reduced, and abrasion of the packing sealing device is reduced. The middle cavity sealing performance and the product service life are improved; the upper valve clack and the lower valve clack are of a flexible valve clack structure, collision between the upper valve clack and the valve seat during closing is reduced, and the valve is suitable for high-frequency opening and closing working conditions.

Description

Technical Field

[0001] The utility model belongs to the field of valves, and in particular relates to a three-way switching valve. The utility model is suitable for three-way medium working conditions with frequent switching. Background Art

[0002] The valve body of the three-way switching valve has an inlet pipe and two outlet pipes. The inlet pipe is connected to one of the outlet pipes by switching the valve disc to realize the reversing flow of the medium. For example, in the three-way switching valve with patent number CN201921196724.2, the sealing parts in the valve body are all arranged on the front end of the valve core, which is not only convenient to install, but also the sealing structure of the front end of the valve core is easy to replace and maintain. The sealing component at the rear end of the valve core can extend the service life of the sealing component by compensating the spring pressure. Its main disadvantages are: in the working condition of frequent reversal of the medium pipeline, during the switching of the valve disc, the medium pressure produces radial force on the valve disc, causing the center line of the valve disc and the valve seat to shift, resulting in the offset of the matching position of the valve disc sealing surface and the valve seat sealing surface, the sealing pressure ratio of the sealing pair in the circumferential direction is inconsistent, and the sealing pressure ratio of the sealing pair near the medium inlet is low, which is prone to sealing leakage; at the same time, the medium pressure produces radial thrust on the valve stem, increases the friction of the valve stem movement, increases the opening and closing torque, causes the sealing packing at the valve stem to wear more, affects the sealing performance of the middle cavity, and shortens the service life of the product. Summary of the invention

[0003] The utility model aims at the shortcomings of the prior art and provides a high-frequency on-off switching three-way valve which can prevent radial deviation of the valve disc and the valve stem during the switching process, has uniform sealing pressure in the circumferential direction of the sealing pair, has less wear on the sealing packing, has small opening and closing torque, has reliable sealing performance and long service life.

[0004] The technical scheme of the utility model is: a high-frequency switch three-way valve, including a valve body, a valve seat, a valve disc, a valve stem, and a valve cover. The valve body has an inlet channel and two outlet channels. The valve seats are respectively installed between the two outlet channels and the inlet channel. The two valve seats are symmetrically and concentrically installed on both sides of the center line of the inlet channel. The valve disc has an upper valve disc and a lower valve disc coaxially installed on the valve stem. The two valve discs cooperate with the two valve seats to form an upper sealing pair and a lower sealing pair. The two sealing pairs realize on-off switching. A packing sealing device is arranged between the valve stem and the valve cover. It is characterized in that: a guide positioning device that cooperates with the upper valve disc and the lower valve disc is respectively arranged in the two outlet channels of the valve body, and the guide positioning device is composed of a guide positioning device. The ring cooperates with the guide grooves on the outer circumference of the upper valve disc and the lower valve disc, and the guide positioning rings are fixedly installed in the outlet chambers of the two valve seats respectively; the upper valve disc and the lower valve disc are respectively composed of a base, a sealing ring, an annular disc spring, and a pressure cover to form a flexible valve disc. The two bases adopt a cone structure and are concentrically fixed on the lower valve stem. The large diameter ends of the cones are respectively located in the outlet chambers of the two valve seats. The sealing ring is formed by integral hard alloy processing and is installed between the annular step in the plane of the large diameter end of the cone and the annular step of the pressure cover. The annular disc spring is arranged between the sealing ring and the annular step of the pressure cover. The pressure cover and the base are fixedly connected by screws, and the inner hole wall of the sealing ring and the cylindrical surface of the annular step of the base are dynamically sealed.

[0005] Preferably, the guide and positioning ring adopts a squirrel-cage cylindrical ring, and the two squirrel-cage cylindrical rings are fixed and pressed in the outlet chambers of the two valve seats by the valve cover and the pressure ring respectively, and an annular flow channel is provided between the outer circular surface of the squirrel-cage cylindrical ring and the inner wall of the outlet chamber of the valve seat; a plurality of radial guide and positioning ribs are evenly arranged on the inner circumference of the squirrel-cage cylindrical ring, and guide grooves are evenly arranged on the outer circumference of the pressure cover to axially slide with the radial guide and positioning ribs, so as to form radial positioning and axial guiding of the upper valve disc and the lower valve disc, and a medium flow window is formed between two adjacent radial guide and positioning ribs.

[0006] Preferably, the valve stem is composed of an upper valve stem and a lower valve stem, the lower valve stem is located at the lower end of the base of the upper valve disc, and the two are an integrated structure, and the lower valve disc is installed on the radial boss in the middle of the lower valve stem by a nut and a locking nut.

[0007] Preferably, a radial locating pin is provided between the locking nut and the lower valve stem.

[0008] Preferably, a radial boss is provided at the lower end of the upper valve stem, and the radial boss is pressed into a recessed hole formed in the center of the plane of the base of the upper valve disc by a pressure cover, and disc springs are respectively installed between the upper annular surface of the radial boss and the pressure cover, and between the lower end surface of the radial boss and the recessed hole.

[0009] Preferably, a guide device is provided at the lower part of the lower valve stem, the inner hole of the guide ring of the guide device is movably matched with the outer cylindrical surface of the lower end of the lower valve stem, and the outer cylindrical surface of the guide ring is fixedly connected to the inner wall of one of the outlet channels through guide ribs.

[0010] Preferably, the packing sealing device is composed of a composite metal sealing structure consisting of a bowl-shaped metal sealing ring and a graphite packing, the inner hole wall of the bowl-shaped metal sealing ring dynamically seals with the outer cylindrical surface of the valve stem, and the lower end of the graphite packing is embedded between the upper outer conical surface of the bowl-shaped metal sealing ring and the valve cover.

[0011] Compared with the prior art, the utility model has the following beneficial effects: guiding and positioning devices that cooperate with the upper valve disc and the lower valve disc are respectively arranged in the two outlet channels of the valve body, so as to realize radial positioning and axial guiding of the upper valve disc and the lower valve disc, prevent the upper valve disc and the lower valve disc from generating radial displacement under the radial thrust of the inlet medium, keep the sealing pressure ratio of the upper sealing pair and the lower sealing pair in the circumferential direction uniform, improve the sealing performance of the sealing pair, reduce the radial pressure of the valve stem on the packing sealing device, reduce the wear of the packing sealing device, improve the sealing performance of the middle cavity and the service life of the product; the upper valve disc and the lower valve disc adopt a flexible valve disc structure, reduce the collision between the valve seat and the valve seat when closing, and are suitable for high-frequency opening and closing conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the utility model.

[0013] In the figure: 1 outlet channel, 2 valve seat, 3 valve body, 4 guide positioning ring, 5 valve cover, 6 bowl-shaped metal sealing ring, 7 graphite packing, 8 upper valve stem, 9 pressure cover, 10 annular disc spring, 11 sealing ring, 12 inlet channel, 13 disc spring, 14 base, 15 annular flow channel, 16 lower valve stem, 17 pressure ring, 18 guide ring, 19 guide rib, 20 radial guide positioning rib, 21 nut, 22 locking nut, 23 positioning pin, 24 screw, 25 radial boss. DETAILED DESCRIPTION

[0014] like Figure 1The high-frequency on-off switching three-way valve shown in the figure comprises a valve body 3, a valve seat 2, a valve disc, a valve stem and a valve cover 5. The valve body 3 has an inlet channel 12 and two outlet channels 1. The valve seats 2 are respectively installed between the two outlet channels 1 and the inlet channel 12. The two valve seats 2 are symmetrically and concentrically installed on both sides of the center line of the inlet channel 12. The flow channel center line of the valve seat 2 intersects vertically with the center line of the inlet channel 12. The valve disc comprises an upper valve disc and a lower valve disc coaxially installed on the valve stem. The center line of the valve stem coincides with the flow channel center line of the valve seat 2. The two valve discs cooperate with the two valve seats to form an upper sealing pair and a lower sealing pair. The two sealing pairs realize on-off switching, that is, when the upper sealing pair is closed, the lower sealing pair is opened and the upper sealing pair is closed. When the sealing pair is opened, the lower sealing pair is closed to achieve alternating communication between the inlet channel 12 and the two outlet channels 1, and a packing sealing device is arranged between the valve stem and the valve cover 5 to achieve sealing between the valve stem and the valve cover 5; its characteristics are: a guide positioning device cooperating with the upper valve disc and the lower valve disc is respectively arranged in the two outlet channels 1 of the valve body 3, and the guide positioning device is composed of a guide positioning ring 4 and a guide groove on the outer circumference of the upper valve disc and the lower valve disc to cooperate with each other, so as to achieve radial positioning and axial guidance of the upper valve disc and the lower valve disc, prevent the radial thrust of the inlet medium on the upper valve disc and the lower valve disc, cause the upper valve disc and the lower valve disc to produce radial displacement, and cause the concentricity of the valve disc and the valve seat 2 to deviate, resulting in the sealing pair. The sealing pressure ratio in the circumferential direction is inconsistent, which reduces the sealing performance of the sealing pair. At the same time, the valve disc drives the valve stem to produce radial deviation, which causes the valve stem to produce radial pressure on the packing sealing device, increases the wear on the sealing packing, and affects the sealing performance of the middle cavity and the service life of the product; the guide positioning ring 4 is fixedly installed in the outlet cavity of the two valve seats 2 respectively; the upper valve disc and the lower valve disc are respectively composed of a base 14, a sealing ring 11, an annular disc spring 10, and a pressure cover 9 to form a flexible valve disc, which reduces the impact between the valve disc and the sealing surface of the valve seat 2 when closing, and prevents damage to the sealing surface under high-frequency opening and closing conditions. The two bases 14 adopt a cone structure with a cone angle facing the inlet channel 12, that is, the large diameter end of the cone is located at the outlet of the two valve seats 2 The sealing ring 11 is formed by integral hard alloy and installed between the annular step in the plane of the large diameter end of the cone and the annular step of the gland 9. It has high hardness and high strength and meets the requirements of high-frequency switching conditions. The annular disc spring 10 is arranged between the sealing ring 11 and the annular step of the gland 9, so that the sealing ring 11 can float axially when closed to form a flexible sealing pair. The gland 9 and the base 14 are fixedly connected by screws 24. The screws 24 are evenly arranged in the circumferential direction in the plane of the gland 9. The inner hole wall of the sealing ring 11 and the inner cylindrical surface of the annular step of the base 14 are dynamically sealed, so that the sealing ring 11 can float axially when closed.

[0015] The guide and positioning ring 4 adopts a squirrel cage cylindrical ring structure. The two squirrel cage cylindrical rings are fixedly pressed in the outlet chambers of the two valve seats 2 by the valve cover 5 and the pressure ring 17 respectively. An annular flow channel 15 is provided between the outer circumference of the squirrel cage cylindrical ring and the inner wall of the outlet chamber of the valve seat 2; a plurality of radial guide and positioning ribs 20 are evenly arranged on the inner circumference of the squirrel cage cylindrical ring, and guide grooves are evenly arranged on the outer circumference of the pressure cover 9 to axially slide with the radial guide and positioning ribs 20 to constitute radial positioning and axial guidance of the upper valve disc and the lower valve disc, and a medium flow window is formed between two adjacent radial guide and positioning ribs 20, and the fluid enters the annular flow channel 15 from the medium flow window to the outlet channel 1.

[0016] The valve stem is composed of an upper valve stem 8 and a lower valve stem 16. The lower valve stem 16 is located at the lower end of the base 14 of the upper valve disc. The two are an integrated structure and are precisely machined by a machining center to reduce assembly errors and improve the concentricity of the lower valve stem 16 and the upper valve disc. The lower valve disc is installed on the radial boss in the middle of the lower valve stem 16 by a nut 21 and a locking nut 22.

[0017] A radial positioning pin 23 is provided between the locking nut 22 and the lower valve stem 16 to prevent the locking nut 22 from loosening and improve the reliability of fixing the lower valve disc.

[0018] A radial boss 25 is provided at the lower end of the upper valve stem 8, and the radial boss 25 is pressed by the pressure cover 9 into a concave hole formed in the center of the plane on the base 14 of the upper valve disc. Disc springs 13 are respectively installed between the upper annular surface of the radial boss 25 and the pressure cover 9, and between the lower end surface of the radial boss 25 and the concave hole, so that the upper valve disc, the lower valve disc and the valve seat 2 form a flexible fit, and a buffer structure is formed when closed to reduce the collision of the sealing surface.

[0019] A guide device is provided at the lower part of the lower valve stem 16. The inner hole of the guide ring 18 of the guide device is matched with the outer cylindrical surface of the lower end of the lower valve stem 16. The outer cylindrical surface of the guide ring 18 is fixedly connected to the inner wall of the outlet channel 1 outside the lower valve stem 16 through the guide rib 19, thereby enhancing the guiding performance of the axial movement of the valve stem.

[0020] The packing sealing device is composed of a composite metal sealing structure consisting of a bowl-shaped metal sealing ring 6 and a graphite packing 7. The inner hole wall of the bowl-shaped metal sealing ring 6 is dynamically sealed with the outer cylindrical surface of the upper valve stem 8. The lower end of the graphite packing 7 is embedded between the upper outer conical surface of the bowl-shaped metal sealing ring 6 and the valve cover 5. The medium pressure pushes the bowl-shaped metal sealing ring 6 to move upward. The outer conical surface thereof radially contracts under the wedging force of the graphite packing 7 to be pressed and sealed with the outer cylindrical surface of the upper valve stem 8 to realize the medium self-sealing function.

Claims

1. A high-frequency on-off switching three-way valve, comprising a valve body (3), a valve seat (2), a valve disc, a valve stem, and a valve cover (5), wherein the valve body (3) has an inlet channel (12) and two outlet channels (1), the valve seats (2) are respectively installed between the two outlet channels (1) and the inlet channel (12), the two valve seats (2) are symmetrically and concentrically installed on both sides of the center line of the inlet channel (12), the valve disc comprises an upper valve disc and a lower valve disc coaxially installed on the valve stem, the two valve discs cooperate with the two valve seats (2) to form an upper sealing pair and a lower sealing pair, the two sealing pairs form an on-off switch, and a packing sealing device is arranged between the valve stem and the valve cover (5); the characteristics are: A guide positioning device that cooperates with the upper valve disc and the lower valve disc is respectively arranged in the two outlet passages (1) of the valve body (3), and the guide positioning device is composed of a guide positioning ring (4) that cooperates with the guide grooves on the outer circumferences of the upper valve disc and the lower valve disc. The guide positioning ring (4) is respectively fixedly installed in the outlet chambers of the two valve seats (2); the upper valve disc and the lower valve disc are respectively composed of a base (14), a sealing ring (11), an annular disc spring (10), and a pressure cover (9) to form a flexible valve disc, and the two bases (14) are tapered toward the inlet. The conical structure of the channel (12) is fixedly mounted concentrically on the valve stem. The sealing ring (11) is formed by integral hard alloy processing and is mounted between the annular step in the plane of the large diameter end of the cone and the annular step of the gland (9). The annular disc spring (10) is arranged between the sealing ring (11) and the annular step of the gland (9). The gland (9) and the base (14) are fixedly connected by screws (24). The inner hole wall of the sealing ring (11) and the inner cylindrical surface of the annular step of the base (14) are dynamically sealed.

2. The high-frequency on-off switching three-way valve according to claim 1 is characterized in that: The guide positioning ring (4) adopts a squirrel cage cylindrical ring structure. The two squirrel cage cylindrical rings are fixedly pressed into the outlet chambers of the two valve seats (2) by the valve cover (5) and the pressure ring (17), respectively. An annular flow channel (15) is provided between the outer circumference of the squirrel cage cylindrical ring and the inner wall of the outlet chamber of the valve seat (2). A plurality of radial guide positioning ribs (20) are evenly arranged on the inner circumference of the squirrel cage cylindrical ring. Guide grooves are evenly arranged on the outer circumference of the pressure cover (9) to axially slide with the radial guide positioning ribs (20), thereby forming radial positioning and axial guidance of the upper valve disc and the lower valve disc. A medium flow window is formed between two adjacent radial guide positioning ribs (20).

3. The high-frequency on-off switching three-way valve according to claim 2 is characterized in that: The valve stem is composed of an upper valve stem (8) and a lower valve stem (16). The lower valve stem (16) and the base (14) of the upper valve disc are of an integral structure. The lower valve disc is mounted on a radial boss in the middle of the lower valve stem (16) by a nut (21) and a locking nut (22).

4. The high-frequency on-off switching three-way valve according to claim 3 is characterized in that: A radial positioning pin (23) is provided between the locking nut (22) and the lower valve stem (16).

5. The high-frequency on-off switching three-way valve according to claim 3 is characterized in that: A radial boss (25) is provided at the lower end of the upper valve stem (8). The radial boss (25) is press-fitted into a recessed hole formed at the center of the upper plane of the base (14) of the upper valve disc by a gland (9). Disc springs (13) are respectively installed between the upper annular surface of the radial boss (25) and the gland (9) and between the lower end surface of the radial boss (25) and the recessed hole.

6. The high-frequency on-off switching three-way valve according to claim 3, 4 or 5, characterized in that: A guide device is provided at the lower portion of the lower valve stem (16); an inner hole of a guide ring (18) of the guide device is matched with an outer cylindrical surface of the lower end of the lower valve stem (16); and the outer cylindrical surface of the guide ring (18) is fixedly connected to an inner wall of an outlet passage (1) outside the lower valve stem (16) via a guide rib (19).

7. The high-frequency on-off switching three-way valve according to claim 1 or 2 or 3 or 4 or 5, characterized in that: The packing sealing device is composed of a bowl-shaped metal sealing ring (6) and a graphite packing (7) to form a composite metal sealing structure. The inner hole wall of the bowl-shaped metal sealing ring (6) and the outer cylindrical surface of the upper valve stem (8) are dynamically sealed, and the lower end of the graphite packing (7) is embedded between the upper outer conical surface of the bowl-shaped metal sealing ring (6) and the valve cover (5).

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