A valve core structure of a screw rod upper-mounted type valve and the valve

Abstract

The utility model discloses a kind of valve core structure and valve of screw rod upper mounting type convenient to maintain, it is related to fluid control technical field, applicable to temperature control valve, stop valve and other valves depending on valve core axial lifting movement.The valve core structure includes bonnet, water pressure plate and screw rod, bonnet is equipped with axially through central hole and inner step, water pressure plate is loaded from central hole lower end and is limited by inner step, screw rod is loaded from central hole upper end and is limited by outer step, both detachable connection and synchronous axial movement to control water flow passage on-off;Bonnet upper end is screwed locking nut, and annular inner groove forms limiting cavity, first sealing ring and second sealing ring are arranged on the outer periphery of screw rod, and anti-rotation limiting structure is arranged between water pressure plate and bonnet.The utility model is designed with screw rod upper mounting type, without special tool, sealing ring can be disassembled and replaced on site, solve the defect that existing valve core is not repairable, maintenance cost is high, while simple process, reliable sealing, adapt to heating, water supply and drainage and other various fluid control scenes.

Description

Technical Field

[0001] This utility model relates to the field of fluid control technology, and in particular to a valve core structure with a lead screw mounting structure that is easy to maintain, and a valve using the valve core. Background Technology

[0002] A valve is a device used to control the flow of fluids (liquids, gases, gas-liquid mixtures, etc.) in a pipeline system. It can achieve functions such as fluid on / off switching, flow regulation, pressure control, or flow direction switching by changing the cross-sectional area of ​​its internal passage. There are many types of valves, including ball valves, gate valves, and thermostatic valves. However, different types of valves differ in their opening and closing movements and flow control principles. For example, the valve core of a ball valve is a ball (with a through-hole) that rotates (usually 90° to open and close). On / off switching is achieved through the alignment / misalignment of the ball's through-hole with the pipeline passage. This is an on / off type of flow control, offering excellent sealing in the fully open / fully closed state, but with relatively weak regulating performance. Gate valves and thermostatic valves, on the other hand, both use axial lifting movement of the valve core to open and close the sealing surface. The only difference is that thermostatic valves have an added temperature-sensing automatic adjustment module in their actuation mechanism.

[0003] Thermostatic valves and gate valves are commonly used flow control valves in HVAC and water supply and drainage systems. Both rely on the axial movement of the valve core to achieve medium flow control and regulation. As the core functional unit of both types of valves, the structure of the valve core directly determines the sealing reliability, regulation accuracy, and maintenance convenience. There are two main types of valve cores used in existing thermostatic valves and gate valves: The first type uses a snap ring fixing type, where the lead screw is installed from the bottom and limited by a snap ring at the top. After assembly, the lead screw cannot be removed without damaging the valve body, and leakage necessitates the complete scrapping of the valve. The snap ring is at risk of falling off, and the handwheel is supported only by two O-rings at the bottom, making the lead screw prone to wobbling over long-term use. The second type uses a press-fit riveting type, where the lead screw is installed from the bottom, with a groove machined at the tail. A special servo press is used to press a copper sleeve into the groove to form an axial limit. This requires factory-grade equipment and cannot be repaired on-site. As the press-fit interference decreases with temperature cycles, the lead screw is prone to shifting downwards, leading to sealing failure.

[0004] The common drawback of the two types of structures mentioned above is that they are "unrepairable." Once the sealing ring ages, the entire valve core needs to be replaced. This leads to high equipment maintenance costs and long pipeline downtime, regardless of whether it is used in a temperature control valve or a shut-off valve. This utility model proposes an improvement to address the above-mentioned drawbacks. Utility Model Content

[0005] The purpose of this utility model is to provide a valve core with a screw-mounted structure that is easy to maintain, and a valve using this valve core, mainly a valve that relies on the axial lifting and lowering movement of the valve core, such as a temperature control valve and a shut-off valve.

[0006] The purpose of this utility model is achieved as follows: a screw-mounted valve core structure that is easy to maintain is installed on the valve body, including a valve cap, a pressure plate, and a screw. The valve cap has a central hole that extends axially, and an inner step is provided in the central hole. An outer step is provided on the outer periphery of the upper end of the screw. The pressure plate is installed from the lower end of the central hole and its upward movement is restricted by the inner step. The screw is installed from the upper end of the central hole and its downward movement is restricted by the outer step. The lower end of the screw is detachably connected to the pressure plate. When the screw is driven by an external force to rotate and move axially up and down, the pressure plate moves axially synchronously with the screw to close or open the water flow channel of the valve body.

[0007] In the above-mentioned screw-mounted valve core structure, the inner wall of the upper end of the valve cap is provided with an annular inner groove, and the outer wall is screwed with a locking nut. When the locking nut is screwed into the valve cap, the annular inner groove and the locking nut together form a limiting cavity, which allows the outer step to move up and down with the axial direction of the screw.

[0008] In the above-mentioned screw-mounted valve core structure, the outer periphery of the screw is provided with an upper ring groove and a lower ring groove arranged in parallel. The upper ring groove and the lower ring groove are located above and below the outer step, respectively. A first sealing ring is provided in the upper ring groove. The first sealing ring hugs the screw and is limited by the end face of the locking nut, thus forming a static seal and flexible support. A second sealing ring is provided in the lower ring groove. The second sealing ring is radially attached to the inner wall of the central hole to form a static seal.

[0009] In the above-mentioned screw-mounted valve core structure, there are two lower annular grooves, which are arranged parallel to each other. The second sealing ring is provided in each lower annular groove, and the two second sealing rings together form a seal on the inner wall of the valve cap center hole.

[0010] In the aforementioned screw-mounted valve core structure, the lower end of the screw is detachably connected to the pressure plate via a threaded connection. Specifically, the pressure plate has an internal thread in its upper countersunk hole, and the lower cylindrical section of the screw has an external thread. The engagement of the internal and external threads forms a detachable synchronous lifting structure. In this screw-mounted valve core structure, a limiting structure is formed between the outer periphery of the pressure plate and the inner wall of the valve cap's central hole to prevent the pressure plate from rotating within the central hole.

[0011] In the above-mentioned screw-mounted valve core structure, the limiting structure is provided with an anti-rotation surface on the outer periphery of the pressure plate and a positioning surface adapted to the anti-rotation surface on the inner wall of the central hole.

[0012] A valve that is easy to maintain includes the valve core structure described above. The valve is a temperature control valve or a gate valve, the valve body is a two-way or three-way structure, and it is equipped with a handwheel or an electric actuator.

[0013] The outstanding and beneficial technical effects of this utility model compared to the prior art are:

[0014] 1. This utility model adopts a top-mounted screw type, that is, the screw is installed from the top. This structure is easy to maintain. If the sealing ring is worn or the seal fails, simply unscrew the locking nut and take the screw upward to replace the new sealing ring. On-site maintenance can be performed without special tools.

[0015] 2. This utility model has multiple seals and flexible support, which makes the handwheel drive screw feel better and has a longer service life.

[0016] 3. This utility model eliminates the existing valve core structure that uses snap rings and riveting, which simplifies the process and effectively reduces costs. Attached Figure Description

[0017] Figure 1 Structural cross-sectional view of this utility model;

[0018] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0019] Figure 3 One of the schematic diagrams of the valve cap, pressure plate and screw structure of this utility model;

[0020] Figure 4 Schematic diagram of the valve cap structure of this utility model;

[0021] Figure 5 Schematic diagram of the valve cap, pressure plate and screw structure of this utility model (II);

[0022] Figure 6 Schematic diagram of the valve cap, pressure plate and screw structure of this utility model (Part 3);

[0023] Figure 7 One of the structural schematic diagrams of the valve of this utility model;

[0024] Figure 8 The second schematic diagram of the valve structure of this utility model;

[0025] The meaning of the labels in the diagram:

[0026] 1-Valve cap; 11-Inner step; 12-Annular inner groove; 13-Positioning surface;

[0027] 2-Water pressure plate; 21-Anti-rotation surface;

[0028] 3-Screw; 31-Outer step; 32-Upper annular groove; 33-Lower annular groove;

[0029] 4- Locking nut; 51- First sealing ring; 52- Second sealing ring;

[0030] 100 - Valve body; 200 - Handwheel. Detailed Implementation

[0031] The present invention will be further described below with reference to specific embodiments:

[0032] like Figures 1-8 As shown, a screw-mounted valve core structure for easy maintenance is mounted on a valve body 100, including a valve cap 1, a pressure plate 2, and a screw 3. The valve cap 1 has a central hole extending axially, with an inner step 11 inside the central hole. The upper end of the screw 3 has an outer step 31 on its outer periphery. The pressure plate 2 is inserted into the lower end of the central hole and its upward movement is restricted by the inner step 11. The screw 3 is inserted into the upper end of the central hole and its downward movement is restricted by the outer step 31. The lower end of the screw 3 is detachably connected to the pressure plate 2. When the screw 3 is driven by an external force to rotate and move axially up and down, the pressure plate 2 and the screw 3 move axially synchronously to close or open the water flow channel of the valve body. This technical solution achieves the core function of "detachable top-mounted," providing great convenience for on-site maintenance.

[0033] Furthermore, the upper end of the valve cap 1 has an annular inner groove 12 on its inner side wall and a locking nut 4 screwed onto its outer side wall. When the locking nut 4 is screwed onto the valve cap 1, the annular inner groove 12 and the locking nut 4 together form a limiting cavity, allowing the outer step 31 to move up and down axially with the lead screw 3. In this technical solution, the lead screw is provided with full-stroke axial travel limitation to prevent overtravel and disengagement; at the same time, a detachable port is formed, and the valve core can be removed by removing the locking nut, facilitating quick on-site maintenance.

[0034] Furthermore, the outer periphery of the lead screw 3 is provided with an upper annular groove 32 and a lower annular groove 33 arranged parallel to each other. The upper annular groove 32 and the lower annular groove 33 are located above and below the outer step 31, respectively. A first sealing ring 51 is provided in the upper annular groove 32. The first sealing ring 51 hugs the lead screw 3 and is limited by the end face of the locking nut 4, thus forming a static seal and flexible support. A second sealing ring 52 is provided in the lower annular groove 33. The second sealing ring 52 is radially attached to the inner wall of the central hole to form a static seal. In this technical solution, the first sealing ring simultaneously achieves a static seal and flexible support, resulting in a small amount of handwheel wobble. In addition, the second sealing ring forms a static seal, effectively preventing the medium from entering the limiting cavity, resulting in a good sealing effect and a long service life.

[0035] Furthermore, there are two lower annular grooves 33, which are arranged parallel to each other vertically. Each lower annular groove 33 contains the aforementioned second sealing ring 52, and the two second sealing rings 52 together form a seal against the inner wall of the central hole of the valve cap 1. In this technical solution, the lower annular grooves 33 are arranged in two parallel sections, i.e., axially spaced parallel. Each lower annular groove 33 is equipped with a second sealing ring 52, forming a double seal against the inner wall of the central hole. Even if one seal ages, the sealing reliability can still be guaranteed; at the same time, the risk of water entering the limiting cavity is further reduced.

[0036] In this technical solution, an inner step 11 is machined at the lower end of the central hole of the valve cap 1, and an external thread and an annular inner groove 12 are machined at the upper end. The pressure plate 2 is installed from the lower end and is limited by the inner step 11; an internal thread is machined in the countersunk hole at the upper end of the pressure plate 2. The lead screw 3 is installed from the upper end, and the outer step 31 sits at the bottom of the annular inner groove 12, forming a limit; the lower cylindrical section of the lead screw 3 is machined with an external thread and screwed into the internal thread of the pressure plate 2, forming a detachable threaded pair. The locking nut 4 is screwed into the external thread of the valve cap 1, forming a limiting cavity with the annular inner groove 12, allowing the outer step 31 to have a full axial movement stroke.

[0037] Furthermore, in the aforementioned screw-mounted valve core structure, the lower end of the screw 3 is detachably connected to the pressure plate 2 via a threaded connection. Specifically, the pressure plate 2 has an internal thread in its upper countersunk hole, and the lower cylindrical section of the screw 3 has an external thread. The engagement of the internal and external threads forms a detachable synchronous lifting structure. This structure allows for quick rotation and disassembly of the screw 3, enabling users to perform maintenance on the valve core. During maintenance, the locking nut 4 is unscrewed, the screw 3 is rotated to disengage its external thread from the pressure plate's internal thread, and then the screw 3 is pulled out of the central hole to replace all sealing rings (the first and second sealing rings). The first and second sealing rings can preferably be standard parts such as O-rings.

[0038] Furthermore, a limiting structure is formed between the outer periphery of the pressure plate 2 and the inner wall of the central hole of the valve cap 1 to prevent the pressure plate from rotating in the central hole.

[0039] Furthermore, the limiting structure consists of an anti-rotation surface 21 on the outer periphery of the pressure plate 2, and a positioning surface 13 adapted to the anti-rotation surface on the inner wall of the central hole. In this technical solution, the anti-rotation surface 21 and the positioning surface 13 are set as regular polygons, which facilitates their installation.

[0040] A valve that is easy to maintain includes the valve core structure described above. The valve is a two-way or three-way structure and is equipped with a handwheel 200 or an electric actuator. The valve in this technical solution specifically refers to a valve that uses axial lifting motion to open and close the sealing surface, such as a temperature control valve and a gate valve.

[0041] The above embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of protection of the present utility model. Therefore, all equivalent changes made to the structure, shape, and principle of the present utility model should be covered within the scope of protection of the present utility model.

Claims

1. A screw-mounted valve core structure for easy maintenance, mounted on the valve body (100), characterized in that: The valve includes a valve cap (1), a pressure plate (2), and a screw (3). The valve cap (1) has a central hole that extends through the axial direction. An inner step (11) is provided in the central hole. An outer step (31) is provided on the outer periphery of the upper end of the screw (3). The pressure plate (2) is inserted from the lower end of the central hole and is restricted from moving upward by the inner step (11). The screw (3) is inserted from the upper end of the central hole and is restricted from moving downward by the outer step (31). The lower end of the screw (3) is detachably connected to the pressure plate (2). When the screw (3) is driven by an external force to rotate and move axially up and down, the pressure plate (2) and the screw (3) move axially in sync to close or open the water flow channel of the valve body.

2. The screw-mounted valve core structure according to claim 1, characterized in that: The valve cap (1) has an annular inner groove (12) on the inner side wall of the upper end and a locking nut (4) screwed onto the outer side wall. When the locking nut (4) is screwed into the valve cap (1), the annular inner groove (12) and the locking nut (4) together form a limiting cavity, which allows the outer step (31) to move up and down along the axial direction of the screw (3).

3. The screw-mounted valve core structure according to claim 2, characterized in that: The lead screw (3) has an upper ring groove (32) and a lower ring groove (33) arranged in parallel on its outer periphery. The upper ring groove (32) and the lower ring groove (33) are located above and below the outer step (31), respectively. A first sealing ring (51) is provided in the upper ring groove (32). The first sealing ring (51) hugs the lead screw (3) and is limited by the end face of the locking nut (4), thus forming a static seal and flexible support. A second sealing ring (52) is provided in the lower ring groove (33). The second sealing ring (52) is radially attached to the inner wall of the central hole to form a static seal.

4. The lead screw-mounted valve core structure according to claim 3, characterized in that: The lower annular groove (33) has two sections, and the two lower annular grooves (33) are arranged in parallel. The second sealing ring (52) is provided in each lower annular groove (33), and the two second sealing rings (52) together form a seal on the inner wall of the central hole of the valve cap (1).

5. The screw-mounted valve core structure according to claim 1, characterized in that: The lower end of the lead screw (3) and the pressure plate (2) are detachably connected by a threaded pair. Specifically, the upper end of the pressure plate (2) is provided with an internal thread in the countersunk hole, and the lower end of the lead screw (3) is provided with an external thread. After the internal and external threads are screwed together, a detachable synchronous lifting structure is formed.

6. The screw-mounted valve core structure according to claim 1, characterized in that: A limiting structure is formed between the outer periphery of the pressure plate (2) and the inner wall of the central hole of the valve cap (1) to prevent the pressure plate from rotating in the central hole.

7. The screw-mounted valve core structure according to claim 6, characterized in that: The limiting structure is that the water pressure plate (2) has an anti-rotation surface (21) on its outer periphery and a positioning surface (13) that is adapted to the anti-rotation surface on the inner wall of the central hole.

8. A valve that is easy to maintain, characterized in that, The valve includes the valve core structure described in any one of claims 1-7, wherein the valve is a temperature control valve or a shut-off valve, the valve body (100) has a two-way or three-way structure, and is equipped with a handwheel (200) or an electric actuator.

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