A stop valve

Abstract

The utility model relates to the field of valve application, specifically a stop valve, including a valve body, a valve core assembly and a valve stem, the valve core assembly has a limit groove, the lower end of the valve stem is movably installed in the limit groove, at least one elastic protective member is provided between the bottom end of the valve stem and the valve core assembly, the upper side of the uppermost elastic protective member and the lower side of the lowermost elastic protective member are respectively against the lower end surface of the valve stem and the inner bottom surface of the limit groove, and a buffer cavity is provided between the lower surface of the lowermost elastic protective member and the limit groove. Through the design of the elastic protective member, a compensation stroke and a continuous closing force are provided for the valve closed state, and an initial pre-starting force is provided for the valve opening; the design of pre-compressing the elastic gap compensation member and the elastic protective member in combination with the gland makes a relative force between the valve core body, the gland and the valve stem, avoiding problems such as the valve core body falling off due to loose threads and the sealing surface scouring caused by internal leakage of the valve.

Description

Technical Field

[0001] The utility model relates to the field of valve applications, in particular to a stop valve. Background Art

[0002] In the prior art, the valve core and valve stem of the stop valve are generally connected by a T-slot, so that the valve core is driven to move when the valve stem moves up and down to complete the opening and closing of the valve. In order to avoid the contact part between the valve core and the valve stem head from being crushed, a flat gasket is arranged between the valve stem head and the valve core to increase the hardness of the contact part between the valve core and the valve stem head. In the prior art, in order to ensure the self-alignment of the valve core and the valve seat to achieve a better sealing effect, a gap is arranged between the valve core and the valve stem in the vertical direction. However, when the valve is in the open state, the valve disc is subjected to the force of the medium and there is a phenomenon of continuous up and down movement, which leads to hazards such as medium turbulence and high noise on site.

[0003] In addition, in the prior art, when the stop valve flows in a low-inlet and high-outlet direction, the valve core is continuously acted upon by the medium force when the valve is closed. Since there is no closing force continuously applied to the valve core, the valve core is easily slightly opened. In the small opening state, the medium flow rate is high and cavitation flash is prone to occur, resulting in the sealing surface being quickly eroded and the valve being unable to cut off the medium, and even flushing the valve body, causing external leakage, posing a greater safety risk; and when the medium flows in a high-inlet and low-outlet direction, the initial opening force of the valve is relatively large and it is not easy to open. In addition, in the prior art, the valve inner pressure cover and the valve core are often connected by a thread, but after long-term use, the thread is prone to loosening, causing the valve core to fall off.

[0004] Therefore, it is urgent to design a new stop valve to solve the above problems. Utility Model Content

[0005] The utility model aims to provide a stop valve, which can protect both the valve core and the valve stem during the opening and closing process of the valve through the design of an elastic protective member and a buffer chamber, thereby increasing the service life of the valve; and through the design of an elastic gap compensating member and an elastic protective member, a gland pre-compresses the elastic gap compensating member and the elastic protective member, thereby generating a relative force between the valve core body, the gland and the valve stem, thereby preventing the thread between the valve core body and the gland from loosening after long-term operation, causing the valve core body to fall off, and the valve being unable to be opened and closed.

[0006] In order to solve the above technical problems, the utility model provides a stop valve, including a valve body, a valve core assembly and a valve stem, the valve core assembly having a limit groove, the lower end of the valve stem being movably installed in the limit groove, and at least one elastic protective member being provided between the bottom end of the valve stem and the valve core assembly, the upper side of the top elastic protective member and the lower side of the bottom elastic protective member respectively abutting against the lower end surface of the valve stem and the inner bottom surface of the limit groove, and a buffer cavity being provided between the lower surface of the bottom elastic protective member and the limit groove.

[0007] Furthermore, the lower end surface of the valve stem is a spherical crown surface, and the abutment surface between the upper side of the elastic protection component and the valve stem is a plane.

[0008] Furthermore, the elastic protective parts are stacked and each of the elastic protective parts is a sheet-like structure, which is composed of an upper abutting portion and a buffer arm arranged on the outside of the upper abutting portion, the upper end of the buffer arm surrounds the outside of the upper abutting portion, and the buffer arm is inclined from top to bottom toward the outside of the upper abutting portion.

[0009] Furthermore, the upper surface of the buffer arm is a spherical crown surface or a conical surface.

[0010] Furthermore, the lower surface of the buffer arm is composed of a first part and a second part, the first part is parallel to the upper surface of the buffer arm, and the second part is arranged at the lower side of the first part and is a plane.

[0011] Furthermore, the valve core assembly includes a valve core body and a pressure cover with a through hole, the upper end of the valve core body has a valve core groove, the lower end of the pressure cover extends into the valve core groove and is threadedly connected to it and together with the valve core groove constitutes the limit groove, and at least one elastic gap compensation part is provided between the outer side of the valve stem and the valve core body.

[0012] Furthermore, an annular groove is provided at the lower end of the valve stem, and a mounting groove is formed between the annular groove and the valve core body, and the elastic gap compensation member is installed in the mounting groove.

[0013] Furthermore, the elastic gap compensation member includes two semi-annular members, which are arranged opposite to each other and spliced ​​into a circular ring.

[0014] Furthermore, a boss section is provided at the upper end of the valve core body, the top of the boss section abuts against the gland and the outer side of the boss section is welded and fixed to the gland.

[0015] Furthermore, there are two elastic gap compensators, which are symmetrically and spliced ​​together, and the upper side of the top elastic gap compensator and the lower side of the bottom elastic gap compensator are respectively against the valve stem and the valve core body.

[0016] The beneficial effects of the utility model are:

[0017] 1. The utility model can protect both the valve core and the valve stem during the opening and closing process of the valve through the design of the elastic protective member and the buffer chamber, thereby increasing the service life of the valve; and the lower end face of the valve stem is a spherical crown surface, and the contact surface between the upper side of the elastic protective member and the valve stem is a flat surface, which facilitates the valve stem to achieve self-eccentricity adjustment relative to the valve core body and achieve the purpose of centering.

[0018] 2. The utility model, through the design of the elastic gap compensating member and the elastic protective member, can pre-compress the elastic gap compensating member and the elastic protective member through the pressure cover, so that a relative force is generated between the valve core body, the pressure cover and the valve stem, which can prevent the threads between the valve core body and the pressure cover from loosening after long-term operation, causing the valve core body to fall off and the valve cannot be opened and closed; and when the valve is closed, the elastic gap compensating member and the elastic protective member can be compressed for the second time to continuously provide closing force for the valve core body, avoiding internal leakage of the valve causing erosion of the sealing surface, and even erosion of the valve body, causing greater safety hazards; and when the valve is initially opened, the elastic gap compensating member and the elastic protective member can provide a continuous upward force for the valve stem, which helps to open the valve and reduce the valve opening force.

[0019] 3. In the utility model, there is no gap between the valve core body and the valve stem in the vertical direction, and a flexible connection state can be formed. This can not only prevent the valve core body from moving up and down due to the medium force when the valve is open, causing medium turbulence and high noise on site, but also realize the self-alignment function of the valve core body and the valve seat.

[0020] 4. The utility model is provided with a boss section at the upper end of the valve core body, the top of the boss section is abutted against the gland and the outer side is welded and fixed to the gland, so that the connection between the valve core body and the gland can be more firmly connected, avoiding the phenomenon that the valve core body falls off due to the loosening of the thread between the valve core body and the gland after long-term operation, and the valve cannot be opened and closed.

[0021] 5. The utility model adopts the design of elastic protective parts, elastic gap compensating parts, valve stems and trapezoidal thread sections on the valve stems. When the valve is closed, the valve stem performs secondary compression on the elastic protective parts and the elastic gap compensating parts. The trapezoidal thread sections of the valve stems and the valve stem nut continuously maintain the compensating force, which helps to lock the trapezoidal threads and avoid internal leakage caused by valve displacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a structural schematic diagram of a stop valve according to an embodiment of the utility model;

[0024] Figure 2 yes Figure 1 A magnified image of area A;

[0025] Figure 3 It is a structural schematic diagram of the valve core body in the embodiment of the utility model;

[0026] Figure 4 It is a schematic structural diagram of the upper surface of the buffer arm of the elastic protective member in the embodiment of the utility model being a spherical crown surface;

[0027] Figure 5 It is a schematic structural diagram of the upper surface of the buffer arm of the elastic protective member in the embodiment of the utility model being a conical surface;

[0028] Figure 6 It is a structural schematic diagram of an elastic gap compensation member of an embodiment of the utility model;

[0029] Figure 7 It is a structural cross-sectional view of a butterfly-shaped elastic gap compensating member according to an embodiment of the utility model;

[0030] Figure 8 It is a structural cross-sectional view of an arc-shaped elastic gap compensation member of an embodiment of the utility model;

[0031] In the figure: 1-valve body, 2-valve core assembly, 3-valve stem, 4-elastic protective part, 5-elastic gap compensation part, 21-valve core body, 22-pressure cover, 211-boss section, 31-trapezoidal thread section, 7-valve seat, 8-valve cover, 9-packing, 10-valve stem nut, 11-bracket, 12-handwheel, 41-upper abutment part, 42-buffer arm, 100-buffer chamber. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings of the utility model specification to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0033] In a specific embodiment of the present invention, Figure 1-8 As shown, a stop valve comprises a valve body 1, a valve core assembly 2 and a valve stem 3, wherein the valve core assembly 2 has a limiting groove, the lower end of the valve stem 3 is movably installed in the limiting groove, and at least one elastic protective member 4 is provided between the bottom end of the valve stem 3 and the valve core assembly 2, the upper side of the uppermost elastic protective member 4 and the lower side of the lowermost elastic protective member 4 respectively abut against the lower end surface of the valve stem 3 and the inner bottom surface of the limiting groove, and a buffer cavity 100 is provided between the lower surface of the lowermost elastic protective member 4 and the limiting groove; in this embodiment, through the design of the elastic protective member and the buffer cavity, both the valve core and the valve stem can be protected during the opening and closing process of the valve, thereby improving the service life of the valve, and the elastic material here can be selected from spring steel.

[0034] Specifically, in this embodiment, the lower end face of the valve stem 3 is a spherical crown surface, and the upper side of the elastic protective member 4 abutting against the valve stem 3 is a plane. Through this design, the valve stem 3 can easily achieve self-eccentric adjustment relative to the valve core body 21 to achieve the purpose of centering.

[0035] Specifically, the elastic protective members 4 are stacked and each elastic protective member 4 is a sheet-like structure, which is composed of an upper abutting portion 41 and a buffer arm 42 arranged outside the upper abutting portion 41. The upper end of the buffer arm 42 surrounds the outside of the upper abutting portion 41, and the buffer arm 42 is inclined from top to bottom toward the outside of the upper abutting portion 41. In this embodiment, the number of elastic protective members 4 is set to 1, and in other embodiments, the number of elastic protective members 4 can be 1-10; specifically, in this embodiment, the upper surface of the buffer arm 42 is a spherical crown surface (such as Figure 4 as shown) or conical surface (as Figure 5 As shown in FIG. 4 , the lower surface of the buffer arm 42 is composed of a first portion and a second portion, the first portion is parallel to the upper surface of the buffer arm, and the second portion is arranged at the lower side of the first portion and is a plane.

[0036] Specifically, in this embodiment, the valve core assembly 2 includes a valve core body 21 and a gland 22 with a through hole. The upper end of the valve core body 21 has a valve core groove, and the lower end of the gland 22 extends into the valve core groove and is threadedly connected thereto and together with the valve core groove forms a limit groove. At least one elastic gap compensation member 5 is provided between the outer side of the valve stem 3 and the valve core body 21; the lower end of the valve stem 3 is provided with an annular groove, and the annular groove and the valve core body 21 form a mounting groove, and the elastic gap compensation member 5 is installed in the mounting groove;

[0037] The utility model pre-compresses the elastic gap compensation member 5 and the elastic protection member 4 through the pressure cover 22, so that a relative force is generated between the valve core body 21, the pressure cover 22, and the valve stem 3, which can prevent the threads between the valve core body 21 and the pressure cover 22 from loosening after long-term operation, causing the valve core body 21 to fall off and the valve cannot be opened and closed; in addition, there is no gap between the valve core body 21 and the valve stem 3 in the vertical direction, and a flexible connection state can be formed, which can not only prevent the valve core body 21 from moving up and down due to the force of the medium when the valve is in the open state, causing hazards such as medium turbulence and high noise on site, but also realize the self-alignment function of the valve core body 21 and the valve seat 7.

[0038] Specifically, Figure 3 As shown, in this embodiment, a boss section 211 is provided at the upper end of the valve core body 21, the top of the boss section 211 is against the pressure cover 22 and the outer side thereof is welded and fixed to the pressure cover 22. Through this design, the connection between the valve core body 21 and the pressure cover 22 can be made more secure, thereby preventing the threads between the valve core body 21 and the pressure cover 22 from loosening after long-term operation, causing the valve core body 21 to fall off and the valve to be unable to be opened and closed.

[0039] Specifically, the elastic gap compensation member 5 includes two semi-annular members, which are arranged opposite to each other and spliced ​​into a circular ring (such as Figure 6 Of course, a butterfly-shaped elastic gap compensation member 5 can be selected here, and the structural cross-sectional view is as shown Figure 7 As shown, an arc-shaped elastic gap compensation member 5 can also be selected, and the structural cross-sectional view is as shown in Figure 8 As shown;

[0040] In the present embodiment, there are two elastic gap compensating parts 5, which are symmetrically and spliced ​​together, and the upper side of the top elastic gap compensating part 5 and the lower side of the bottom elastic gap compensating part 5 are respectively against the valve stem 3 and the valve core body 21; of course, in other embodiments, the number of elastic gap compensating parts 5 can also be designed to be four or more according to actual needs.

[0041] In addition, in this embodiment, the stop valve further includes a valve seat 7 and a valve cover 8. The valve seat 7 is arranged in the valve body 1 and is located directly below the valve core body 21. The valve cover 8 is arranged above the valve body 1 and is fixedly connected thereto. A packing 9 is arranged between the valve cover 8 and the valve stem 3. A trapezoidal thread section 31 is arranged at the upper end of the valve stem 3, and the trapezoidal thread section 31 is threadedly connected to a valve stem nut 10. The valve stem nut 10 is rotatably connected to the valve cover 8 through a bracket 11. A hand wheel 12 is fixedly connected to the top of the valve stem nut 10.

[0042] Specifically, the valve drives the stem nut 10 to rotate by rotating the hand wheel 12, and the stem nut 10 and the stem 3 are driven by the trapezoidal thread to drive the stem 3 to move up and down to open and close the valve. When the hand wheel 12 is driven to close the valve, the stem 3 performs secondary compression on the elastic protective member 4 and the elastic gap compensation member 5. This process can continuously provide supplementary sealing force and compensation stroke for the valve core body 21, which can not only prevent the valve core body 21 from being blown open to a smaller opening by the medium force for a long time, resulting in internal leakage of the valve, but also prevent cavitation from occurring in the working state of a small opening. The medium flow rate is extremely high, which quickly erodes the valve sealing surface and even the pressure-bearing valve body, making the valve unable to seal or even causing safety problems; it can also enable the stem 3 to form a continuous upward compensation force and supplementary stroke. The stem 3 is not subject to the medium force fluctuation that causes the trapezoidal nut to be tightened or loosened when screwed together, which helps to lock the trapezoidal nut between the stem 3 and the stem nut 10, and avoids the loose displacement of the trapezoidal transmission thread causing the valve to be laxly closed; in this embodiment, the continuous upward force of the stem 3 helps to open the valve and reduce the valve opening force.

[0043] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope covered by the present invention.

Claims

1. A stop valve, characterized in that: The invention comprises a valve body (1), a valve core assembly (2) and a valve stem (3), wherein the valve core assembly (2) has a limiting groove, the lower end of the valve stem (3) is movably mounted in the limiting groove, at least one elastic protective member (4) is arranged between the bottom end of the valve stem (3) and the valve core assembly (2), the upper side of the uppermost elastic protective member (4) and the lower side of the lowermost elastic protective member (4) respectively abut against the lower end surface of the valve stem (3) and the inner bottom surface of the limiting groove, and a buffer cavity (100) is arranged between the lower surface of the lowermost elastic protective member (4) and the limiting groove.

2. A stop valve according to claim 1, characterized in that: The lower end surface of the valve stem (3) is a spherical crown surface, and the contact surface between the upper side of the elastic protection component (4) and the valve stem (3) is a plane.

3. A stop valve according to claim 2, characterized in that: The elastic protection members (4) are stacked and each of the elastic protection members (4) is a sheet-like structure, which is composed of an upper abutting portion (41) and a buffer arm (42) arranged outside the upper abutting portion (41), the upper end of the buffer arm (42) surrounds the outside of the upper abutting portion (41), and the buffer arm (42) is inclined from top to bottom toward the outside of the upper abutting portion (41).

4. A stop valve according to claim 3, characterized in that: The upper surface of the buffer arm (42) is a spherical crown surface or a conical surface.

5. A stop valve according to claim 4, characterized in that: The lower surface of the buffer arm (42) is composed of a first part and a second part, the first part is parallel to the upper surface of the buffer arm, and the second part is arranged on the lower side of the first part and is a plane.

6. A stop valve according to claim 1, characterized in that: The valve core assembly (2) comprises a valve core body (21) and a pressure cover (22) having a through hole, the upper end of the valve core body (21) having a valve core groove, the lower end of the pressure cover (22) extending into the valve core groove and being threadedly connected thereto and together with the valve core groove forming the limit groove, at least one elastic gap compensation member (5) is provided between the outer side of the valve stem (3) and the valve core body (21).

7. A stop valve according to claim 6, characterized in that: An annular groove is provided at the lower end of the valve stem (3), and a mounting groove is formed between the annular groove and the valve core body (21), and the elastic gap compensation member (5) is installed in the mounting groove.

8. A stop valve according to claim 6, characterized in that: The elastic gap compensating member (5) comprises two semi-annular members, which are arranged opposite to each other and spliced ​​into a circular ring.

9. A stop valve according to claim 6, characterized in that: A boss section (211) is provided at the upper end of the valve core body (21), the top of the boss section (211) abuts against the gland (22) and the outer side of the boss section (211) is welded and fixed to the gland (22).

10. A stop valve according to claim 6, characterized in that: The number of the elastic gap compensating parts (5) is two, and the two elastic gap compensating parts (5) are symmetrically and spliced ​​together. The upper side of the top elastic gap compensating part (5) and the lower side of the bottom elastic gap compensating part (5) are respectively against the valve stem (3) and the valve core body (21).

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