Built-in overpressure and decompression stop valve

Abstract

The utility model discloses a built-in overpressure and decompression stop valve which comprises an upper shell, a lower shell, a diaphragm, a valve rod, a fixed seat, a steel ball lining seat, a valve rod thin neck, a spring sleeve, an overpressure adjusting spring and a decompression adjusting spring, the diaphragm is installed in the shell, the valve rod is vertically installed in the shell, the fixed seat is arranged on the valve rod in a sleeved mode, and the steel ball lining seat is arranged on the valve rod. A plurality of horizontally-arranged through holes are formed in the upper portion of the fixing seat, steel balls are placed in the through holes, the steel ball lining seat is installed on the diaphragm, the upper portion of the fixing seat is sleeved with the steel ball lining seat, a steel ball lining seat boss capable of abutting against the steel balls is arranged on the steel ball lining seat, and concave portions are arranged on the steel ball lining seat and located on the upper side and the lower side of the steel ball lining seat boss. A valve rod thin neck capable of abutting against the steel ball is arranged on the valve rod, the spring sleeve is installed on the upper portion in the shell, and the bottom of the spring sleeve can abut against the top of the diaphragm. The utility model can simultaneously realize overpressure and decompression working conditions, and has the advantages of sensitive response, high cutting speed, simple structure, convenience in adjustment and reliability in use.

Description

Technical Field

[0001] The utility model relates to the technical field of valves, in particular to a built-in overpressure and pressure loss cut-off valve. Background Art

[0002] The emergency shut-off valve is a key safety protection device in the application of gas pressure regulators. In the structure of small and medium-sized pressure regulators, there is usually a built-in shut-off valve with integrated pressure regulation and shut-off.

[0003] Built-in shut-off valves are usually divided into two types based on their structure: axial drive structure and right-angle drive structure. The axial drive structure means that the force balance constructed by the diaphragm and spring is coaxial with the valve stem. A locking device is provided in the diaphragm and spring assembly to directly lock the valve stem. Once the diaphragm senses gas overpressure, the locking device is automatically released to allow the valve stem to trigger the shut-off action.

[0004] The right-angle drive structure means that the force balance constructed by the diaphragm and spring is perpendicular to the valve stem. A locking device is provided in the diaphragm and spring assembly to lock the valve stem with a transition relationship of a right angle. Once the diaphragm senses gas overpressure, the locking device is automatically released to allow the valve stem to trigger the cut-off action.

[0005] The shortcomings of the existing built-in cut-off valve:

[0006] 1. For axial drive structure;

[0007] The lock structure of the axial drive structure in the prior art is directly mounted on the valve stem. When the cut-off action occurs, the valve stem can only move in the closing direction. Therefore, the lock and the valve stem can only be unlocked in the opposite direction. Therefore, it only has a single-direction unlocking movement direction, which can only meet the overpressure cut-off action, but cannot simultaneously achieve the overpressure and underpressure cut-off settings and drives.

[0008] 2. For right-angle drive structure;

[0009] In order to simultaneously achieve the setting and driving of overpressure and underpressure cut-off, the prior art usually adopts a right-angle drive structure. Since the diaphragm, spring, and locking device are not directly mounted on the axial direction of the valve stem, but are associated with the valve stem through a transferred locking device, the unlocking direction of the locking device is not limited by the movement direction of the valve stem.

[0010] However, this vertical transfer relationship makes the cut-off valve structure more complex and asymmetrical, with high manufacturing costs, high matching precision requirements, and great difficulty in parts manufacturing. It can be said that the right-angle drive structure sacrifices the compactness, symmetry and simplicity of the structure in order to achieve both overpressure and underpressure cut-off.

[0011] Therefore, the applicant proposes a built-in overpressure and underpressure cut-off valve to solve the above problems. Utility Model Content

[0012] In view of the deficiencies in the prior art, the utility model aims to provide a built-in overpressure and underpressure cut-off valve.

[0013] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0014] A built-in overpressure and pressure loss cut-off valve, comprising:

[0015] case;

[0016] A diaphragm, wherein the diaphragm is installed inside the housing;

[0017] A valve stem, the valve stem being vertically mounted inside the housing;

[0018] A fixing seat, wherein the fixing seat sleeve is arranged on the valve stem, and a plurality of horizontally arranged through holes are opened on the upper part of the fixing seat, and steel balls are placed in the through holes;

[0019] A steel ball bushing, the steel ball bushing is installed on the diaphragm, and the steel ball bushing is sleeved on the upper part of the fixed seat, the steel ball bushing is provided with a steel ball bushing boss capable of contacting the steel ball, and the steel ball bushing is provided with recessed parts on the upper and lower sides of the steel ball bushing boss;

[0020] A valve stem neck, wherein the valve stem is provided with a valve stem neck capable of contacting with the steel ball;

[0021] A spring sleeve, wherein the spring sleeve is installed in the upper part of the housing, and the bottom of the spring sleeve can abut against the top of the diaphragm;

[0022] An overpressure regulating spring, wherein the overpressure regulating spring sleeve is arranged outside the spring sleeve;

[0023] The pressure loss regulating spring is sleeved outside the valve stem and located inside the spring sleeve.

[0024] Furthermore, the concave portion above the boss of the steel ball seat is a pressure loss release zone, and the concave portion below the boss of the steel ball seat is an overpressure release zone.

[0025] Furthermore, an overpressure regulating plate located on the top of the overpressure regulating spring is slidably installed on the outside of the spring sleeve, an overpressure regulating cover is rotatably installed on the top of the shell, and supporting feet are installed on both sides of the bottom of the overpressure regulating cover. An arc groove for the supporting feet to pass through is opened on the overpressure regulating plate, and the arc groove is slidably matched with the supporting feet. The overpressure regulating plate is threadedly connected to the upper inner wall of the shell.

[0026] Furthermore, a pressure loss regulating plate located at the top of the pressure loss regulating spring is threadedly installed on the inner thread of the spring sleeve, and a pressure loss regulating rod is rotatably installed on the overpressure regulating cover. The pressure loss regulating rod extends into the shell and passes through the pressure loss regulating plate, and the lower part of the pressure loss regulating rod is slidably fitted with the valve stem.

[0027] Furthermore, one end of the pressure loss regulating rod located in the housing is a square structure, and the pressure loss regulating plate is provided with a square hole that slidably cooperates with the pressure loss regulating rod.

[0028] Furthermore, an opening penetrating the top of the pressure loss regulating rod is provided in the pressure loss regulating rod, an indicator rod is slidably provided in the pressure loss regulating rod, and the bottom of the indicator rod is connected to the top of the valve stem.

[0029] Furthermore, a push spring is provided between the bottom of the indicator rod and the inner bottom of the pressure loss regulating rod.

[0030] Furthermore, the diaphragm is provided with a tray located outside the steel ball bushing, and the steel ball bushing is threadedly connected with a pin sleeve that abuts against the tray.

[0031] Furthermore, an elastic clamping ring is installed between the overpressure regulating cover and the shell.

[0032] Furthermore, a mounting platform is installed at the bottom of the shell.

[0033] Compared with the prior art, the utility model provides a built-in overpressure and pressure loss cut-off valve, which has the following beneficial effects:

[0034] 1. In the initial state of the utility model, the steel ball is limited by the steel ball liner boss, so the steel ball is squeezed inward and contacts the cylindrical surface of the thin neck of the valve stem. The steel balls around it embrace the thin neck of the valve stem and block the step on the upper edge of the thin neck of the valve stem. At this time, the steel ball and the steel ball liner realize a locking effect. Because the steel ball blocks the downward movement of the valve stem, the valve stem is in a locked state at this time. By adopting this special locking structure, the steel ball liner, the steel ball and the valve stem can cooperate with each other, so that the steel ball liner has two unlocking movement directions, namely, when the steel ball liner moves forward or reversely, the valve stem can be unlocked, so that the valve stem moves downward to cut off the gas in the valve body. This solves the shortcoming that the axial drive structure cannot realize overpressure and underpressure unlocking at the same time, so that the axial drive structure has the functions of overpressure cutting and underpressure cutting at the same time.

[0035] 2. The utility model adopts this special lock structure, which can be mounted on the axial direction of the valve stem, and is generally presented as an axial drive structure, which solves the problem of irregular and complex shape of the right-angle drive structure;

[0036] 3. The utility model adjusts the tightness of the overpressure regulating spring through the overpressure regulating plate, thereby changing the overpressure setting value, and adjusts the tightness of the underpressure regulating spring through the underpressure regulating plate, thereby changing the underpressure setting value, so that the device can better adapt to overpressure and underpressure working conditions and has better reliability;

[0037] 4. The utility model can realize overpressure and underpressure conditions at the same time, has sensitive response, fast cutting speed, simple structure, convenient adjustment and reliable use. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the cross-sectional structure of the utility model in the initial state;

[0039] Figure 2 It is a schematic diagram of the structure of the utility model in the initial state;

[0040] Figure 3 It is a schematic cross-sectional structure diagram of the diaphragm assembly and the valve stem in the initial state of the utility model;

[0041] Figure 4 It is a schematic diagram of the cross-sectional structure of the utility model in the overpressure cut-off state;

[0042] Figure 5 It is a cross-sectional structural diagram of the cooperation between the diaphragm assembly and the valve stem in the overpressure cut-off state of the utility model;

[0043] Figure 6 It is a schematic diagram of the cross-sectional structure of the utility model in the pressure loss cut-off state;

[0044] Figure 7 It is a schematic cross-sectional structure diagram of the cooperation between the diaphragm assembly and the valve stem in the pressure loss cut-off state of the utility model;

[0045] Figure 8 It is a schematic diagram of the cross-sectional structure of the utility model when it is reset;

[0046] Fig. 9 The utility model is a schematic diagram of the structure of the overpressure regulating cover, the supporting feet and the overpressure regulating plate.

[0047] Markings in the figure: 1. Upper shell; 2. Lower shell; 3. Diaphragm; 4. Valve stem; 41. Valve stem neck; 5. Fixed seat; 6. Steel ball; 7. Steel ball liner; 71. Steel ball liner boss; 8. Spring sleeve; 9. Overpressure regulating spring; 10. Loss of pressure regulating spring; 11. Overpressure regulating plate; 111. Arc groove; 12. Loss of pressure regulating plate; 13. Reset spring; 14. Valve port pad; 15. Cut-off spring; 16. Overpressure regulating cover; 17. Support foot; 18. Loss of pressure regulating rod; 19. Indicator rod; 20. Push spring; 21. Tray; 22. Pin sleeve; 23. Elastic clamp ring; 24. Mounting table. DETAILED DESCRIPTION

[0048] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0049] The standard parts used in the utility model can all be purchased from the market, and special-shaped parts can be customized according to the instructions and the drawings. The specific connection methods of each part adopt the conventional means such as mature bolts, rivets, welding, etc. in the existing technology. The machinery, parts and equipment all adopt the conventional models in the existing technology, and the circuit connection adopts the conventional connection method in the existing technology, which will not be described in detail here.

[0050] It should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0051] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In the description of the present invention, "plurality" means two or more than two, unless otherwise clearly and specifically defined.

[0053] The utility model embodiment provides a built-in overpressure and pressure loss cut-off valve, referring to Figures 1 to 9 , including: an upper shell 1, a lower shell 2, a diaphragm 3, a valve stem 4, a fixing seat 5, a steel ball liner 7, a valve stem neck 41, a spring sleeve 8, an overpressure regulating spring 9 and a pressure loss regulating spring 10;

[0054] case;

[0055] A diaphragm 3, wherein the diaphragm 3 is installed inside the housing;

[0056] A valve stem 4, wherein the valve stem 4 is vertically installed inside the housing;

[0057] A fixing seat 5, wherein the fixing seat 5 is sleeved on the valve stem 4, and a plurality of horizontal through holes are opened on the upper portion of the fixing seat 5, wherein steel balls 6 are placed in the through holes;

[0058] A steel ball liner 7, the steel ball liner 7 is mounted on the diaphragm 3, and the steel ball liner 7 is sleeved on the upper part of the fixing seat 5, the steel ball liner 7 is provided with a steel ball liner boss 71 capable of contacting the steel ball 6, and the steel ball liner 7 is provided with recessed parts on the upper and lower sides of the steel ball liner boss 71;

[0059] A valve stem neck 41, wherein the valve stem 4 is provided with a valve stem neck 41 capable of contacting with the steel ball 6;

[0060] A spring sleeve 8, wherein the spring sleeve 8 is installed in the upper part of the housing, and the bottom of the spring sleeve 8 can abut against the top of the diaphragm 3;

[0061] An overpressure regulating spring 9, wherein the overpressure regulating spring 9 is sleeved outside the spring sleeve 8;

[0062] The pressure loss regulating spring 10 is sleeved on the outside of the valve stem 4 and located inside the spring sleeve 8 .

[0063] Specifically, the shell includes an upper shell 1 and a lower shell 2, the lower shell 2 is installed at the bottom of the upper shell 1, and the upper shell 1 and the lower shell 2 are connected as a whole by bolts; the diaphragm 3 is installed between the upper shell 1 and the lower shell 2, and the edge of the diaphragm 3 is clamped by the upper shell 1 and the lower shell 2 to form a sealing structure; the valve stem 4 is vertically installed at the axial position of the cut-off valve, and the valve stem 4 passes through the lower shell 2; the fixed seat 5 is installed in the lower shell 2, specifically, the fixed seat 5 passes through the lower shell 2 and extends to the bottom of the lower shell 2, the fixed seat 5 and the lower shell 2 are connected by threads, and the fixed seat 5 and the valve stem 4 are slidably connected; the steel ball 6 can move in the through hole, if A number of through holes are arranged in a circular shape on the upper part of the fixing seat 5; the diameter of the valve stem neck 41 is smaller than the diameter of the rest of the valve stem 4, so the upper edge of the valve stem neck 41 has a step; the lower part of the spring sleeve 8 has a step, and the step at the lower part of the spring sleeve 8 is limited by the structure inside the lower shell 2, so the downward movement of the spring sleeve 8 is limited, and the bottom of the overpressure regulating spring 9 is connected to the step at the lower part of the spring sleeve 8; the diaphragm 3 divides the cut-off valve cavity into a monitoring air chamber and an atmospheric pressure chamber, the atmospheric pressure chamber is above the diaphragm 3, and the monitoring air chamber is below the diaphragm 3; a sealing ring is arranged on the upper part of the steel ball liner 7 and the outer circumference of the valve stem 4 to effectively separate the gas in the monitoring air chamber from the outside.

[0064] A return spring 13 sleeved on the outside of the fixing seat 5 is connected between the steel ball liner 7 and the bottom of the lower shell 2; a valve port pad 14 is installed at the bottom of the valve stem 4; a cut-off spring 15 sleeved on the outside of the valve stem 4 is connected between the valve port pad 14 and the fixing seat 5.

[0065] In the initial state, the return spring 13 can provide an upward thrust to the steel ball seat 7, so that the diaphragm 3 is pressed against the bottom of the spring sleeve 8; the valve stem 4 is connected to the valve mouth pad 14 by a thread; when the valve stem 4 is not affected by other external forces, it can be pushed downward together with the valve mouth pad 14 under the downward thrust of the cut-off spring 15 to cut off the gas in the valve body.

[0066] In the initial state, the steel ball 6 is limited by the steel ball seat boss 71, so the steel ball 6 is squeezed inward and contacts the cylindrical surface of the valve stem neck 41. The steel balls 6 around the valve stem neck 41 embrace the valve stem neck 41 and block the step on the upper edge of the valve stem neck 41. At this time, the steel ball 6 and the steel ball seat 7 realize the locking effect. Because the steel ball 6 blocks the downward movement of the valve stem 4, the valve stem 4 is in a locked state at this time.

[0067] Among them, refer to Figure 3 In this embodiment, the concave portion above the steel ball seat boss 71 is a pressure-loss release zone, and the concave portion below the steel ball seat boss 71 is an overpressure release zone.

[0068] Specifically, by setting the underpressure release zone and the overpressure release zone, the valve stem 4 can be unlocked when the steel ball liner 7 moves forward or backward, so that the valve stem 4 moves downward and performs a cutting action downward under the thrust of the cutting spring 15, thereby cutting off the gas in the valve body.

[0069] Reference Figures 1 to 8 In this embodiment, the diaphragm 3 is provided with a tray 21 located outside the steel ball bushing 7, and the steel ball bushing 7 is threadedly connected with a pin sleeve 22 that abuts against the tray 21.

[0070] Specifically, the bottom of the pressure loss regulating spring 10 is connected to the top of the pin sleeve 22; the steel ball seat 7, the diaphragm 3, the tray 21 and the pin sleeve 22 are combined into one, which can be defined as a diaphragm assembly (the same below), and the diaphragm assembly can move upward or downward; in the initial state, the top of the diaphragm assembly is in conflict with the bottom of the spring sleeve 8.

[0071] Reference Figure 1 and Figure 2 In this embodiment, a mounting platform 24 is installed at the bottom of the shell.

[0072] Specifically, a mounting platform 24 is installed at the bottom of the lower shell 2, and the device can be conveniently installed on the valve body through the mounting platform 24, so that the valve port pad 14 cooperates with the valve seat in the valve body to cut off the gas in the valve body.

[0073] Reference Figure 1 and Fig. 9In this embodiment, an overpressure regulating plate 11 located on the top of the overpressure regulating spring 9 is slidably installed on the outside of the spring sleeve 8, an overpressure regulating cover 16 is rotatably installed on the top of the shell, and support feet 17 are installed on both sides of the bottom of the overpressure regulating cover 16. An arc groove 111 is opened on the overpressure regulating plate 11 for the support feet 17 to pass through. The arc groove 111 is slidably matched with the support feet 17, and the overpressure regulating plate 11 is threadedly connected to the upper inner wall of the shell.

[0074] Specifically, an overpressure regulating cover 16 is rotatably installed on the top of the upper shell 1; the overpressure regulating plate 11 is threadedly connected to the inner wall of the upper shell 1; the tightness of the overpressure regulating spring 9 is adjusted by the overpressure regulating plate 11, thereby changing the overpressure setting value; the bottom of the overpressure regulating plate 11 is not connected to the overpressure regulating spring 9; when the overpressure regulating cover 16 is rotated, the overpressure regulating plate 11 can be driven to rotate by the support foot 17, and the overpressure regulating plate 11 can move upward or downward under the action of the thread of the inner wall of the upper shell 1. When the overpressure regulating plate 11 moves downward (that is, the overpressure regulating cover 16 rotates clockwise), the overpressure regulating spring 9 is compressed to increase the overpressure setting value. When the overpressure regulating plate 11 moves upward (that is, the overpressure regulating cover 16 rotates counterclockwise), the overpressure regulating spring 9 is relaxed to reduce the overpressure setting value.

[0075] Among them, refer to Figure 1 , Figure 4 , Figure 6 and Figure 8 In this embodiment, an elastic clamping ring 23 is installed between the overpressure regulating cover 16 and the housing.

[0076] Specifically, an elastic clamp ring 23 is installed between the overpressure regulating cover 16 and the upper shell 1; by setting the elastic clamp ring 23, external water vapor can be effectively prevented from invading the interior of the parts, playing a protective moisture-proof role, and facilitating the sealing cooperation between the overpressure regulating cover 16 and the upper shell 1. A semicircular ring groove cooperating with the elastic clamp ring 23 is provided on the overpressure regulating cover 16.

[0077] Reference Figure 1 , Figure 4 , Figure 6 and Figure 8 In this embodiment, the spring sleeve 8 has an internal threaded installation of a pressure loss regulating plate 12 located at the top of the pressure loss regulating spring 10, and the overpressure regulating cover 16 has a pressure loss regulating rod 18 rotatably installed thereon. The pressure loss regulating rod 18 extends into the housing and passes through the pressure loss regulating plate 12, and the lower part of the pressure loss regulating rod 18 is slidably fitted with the valve stem 4.

[0078] Specifically, the pressure loss regulating rod 18 extends into the upper shell 1; the tightness of the pressure loss regulating spring 10 is adjusted through the pressure loss regulating plate 12, so as to change the pressure loss setting value; the bottom of the pressure loss regulating plate 12 is not connected to the pressure loss regulating spring 10; the upper part of the pressure loss regulating rod 18 passes through the overpressure regulating cover 16 and is blocked by its own step, and then limited by the top clamp ring, so the pressure loss regulating rod 18 and the overpressure regulating cover 16 have the characteristics of axial synchronous movement, but there is no radial limit on them, so the pressure loss regulating rod 18 can be relatively The overpressure regulating cover 16 is rotated independently; the underpressure regulating plate 12 is threadedly connected to the inner wall of the spring sleeve 8; when the underpressure regulating rod 18 is rotated, the underpressure regulating plate 12 can be driven to move upward or downward. When the underpressure regulating plate 12 moves downward (that is, the underpressure regulating rod 18 rotates clockwise), the underpressure regulating spring 10 is compressed to increase the underpressure setting value. When the underpressure regulating plate 12 moves upward (that is, the underpressure regulating rod 18 rotates counterclockwise), the underpressure regulating spring 10 is relaxed to reduce the underpressure setting value.

[0079] Reference Figure 1 , Figure 4 , Figure 6 and Figure 8 In the present embodiment, one end of the pressure loss regulating rod 18 located in the housing is a square structure, and a square hole for slidingly cooperating with the pressure loss regulating rod 18 is provided on the pressure loss regulating plate 12 .

[0080] Specifically, one end of the pressure loss regulating rod 18 located in the upper shell 1 is a square structure; through the arrangement of the square structure, the pressure loss regulating rod 18 can drive the pressure loss regulating plate 12 to move upward and downward when it rotates.

[0081] Reference Figure 1 , Figure 4 , Figure 6 and Figure 8 In this embodiment, an opening penetrating the top of the pressure loss regulating rod 18 is provided in the pressure loss regulating rod 18 , and an indicator rod 19 is slidably provided in the pressure loss regulating rod 18 , and the bottom of the indicator rod 19 is connected to the top of the valve stem 4 .

[0082] Specifically, the indicator rod 19 is located in the opening of the pressure loss regulating rod 18; in the initial state, the indicator rod 19 extends a distance from the top of the pressure loss regulating rod 18, which is convenient for observing whether the cut-off valve is in the cut-off state; a section of the upper part of the valve stem 4 extends into the opening of the pressure loss regulating rod 18 and is connected to the bottom of the indicator rod 19.

[0083] Reference Figure 1 , Figure 4 , Figure 6 and Figure 8 In this embodiment, a push spring 20 is provided between the bottom of the indicator rod 19 and the inner bottom of the pressure loss regulating rod 18 to facilitate the resetting of the overpressure regulating cover 16, the indicator rod 19 and the pressure loss regulating rod 18.

[0084] Working principle: Setting the overpressure setting value and the underpressure setting value: When the overpressure regulating cover 16 is manually rotated, the overpressure regulating plate 11 can be driven to rotate through the support foot 17. The overpressure regulating plate 11 can move upward or downward under the action of the thread on the inner wall of the upper shell 1. When the overpressure regulating plate 11 moves downward (that is, the overpressure regulating cover 16 rotates clockwise), the overpressure regulating spring 9 is compressed to increase the overpressure setting value. When the overpressure regulating plate 11 moves upward (that is, the overpressure regulating cover 16 rotates counterclockwise), the overpressure regulating spring 9 is relaxed to reduce the overpressure setting value.

[0085] When the pressure loss regulating rod 18 is manually rotated, the pressure loss regulating plate 12 can be driven to move upward or downward. When the pressure loss regulating plate 12 moves downward (i.e., the pressure loss regulating rod 18 rotates clockwise), the pressure loss regulating spring 10 is compressed to increase the pressure loss setting value. When the pressure loss regulating plate 12 moves upward (i.e., the pressure loss regulating rod 18 rotates counterclockwise), the pressure loss regulating spring 10 is relaxed to reduce the pressure loss setting value.

[0086] Locked and buckled state: in the initial state, the steel ball liner seat boss 71 is just aligned with the steel ball 6 in the through hole of the fixing seat 5, and the steel ball liner seat boss 71 limits the steel ball 6, so the steel ball 6 is squeezed inward and contacts the cylindrical surface of the valve stem neck 41. The circle of steel balls 6 around the valve stem neck 41 forms an embrace and blocks the step on the upper edge of the valve stem neck 41. At this time, the steel ball 6 and the steel ball liner 7 realize the locking effect. When the valve stem 4 is not affected by other external forces, it can be pushed downward together with the valve port pad 14 under the downward thrust of the cut-off spring 15 to cut off the gas in the valve body. Because the steel ball 6 forms a barrier to the downward movement of the valve stem 4, the valve stem 4 is in a locked and buckled state at this time.

[0087] Overpressure cut-off state: When the measured gas pressure is overpressure, the upward thrust of the gas on the diaphragm 3 becomes larger, thereby pushing the diaphragm assembly upward. The diaphragm assembly transmits the force to the overpressure regulating spring 9 through the spring sleeve 8. At this time, the thrust generated by the overpressure gas pressure on the diaphragm 3 is greater than the overpressure setting value of the overpressure regulating spring 9, so the balance is broken, and the spring sleeve 8 is pushed upward. At the same time, when the steel ball liner 7 moves upward with the diaphragm assembly, the concave part (i.e., the overpressure release area) below the steel ball liner boss 71 is aligned with the steel ball 6, and the thin neck 4 that originally embraces the valve stem is retracted. 1 is no longer restricted, and the force direction of the contact point between the step on the upper edge of the valve stem neck 41 and the steel ball 6 is at a certain outward angle to the axial direction of the valve stem 4. When the outer side of the steel ball 6 is no longer restricted, the step on the upper edge of the valve stem neck 41 transmits the downward thrust of the cutting spring 15 to the contact point with the steel ball 6 and squeezes the steel ball 6 outward through the angle force, so that the steel ball 6 enters the recessed part below the steel ball liner boss 71, and the valve stem 4 is no longer blocked, so it performs a cutting action downward with the cutting spring 15, thereby completing the overpressure cutting.

[0088] Loss of pressure cut-off state: When the measured air pressure loses pressure, the upward thrust of the gas on the diaphragm 3 becomes smaller, and the diaphragm assembly moves downward under the thrust of the loss of pressure regulating spring 10 and separates from the spring sleeve 8. At this time, the upper side of the diaphragm assembly bears the downward thrust of the loss of pressure regulating spring 10, and the lower side bears the upward thrust of the air pressure. When the thrust of the loss of pressure on the diaphragm 3 is less than the loss of pressure setting value of the loss of pressure regulating spring 10, the balance is broken, and the diaphragm assembly continues to move downward under the thrust of the loss of pressure regulating spring 10. At the same time, the steel ball liner 7 moves downward with the diaphragm assembly. During movement, the recessed portion above the steel ball liner boss 71 (i.e., the pressure-loss release zone) is aligned with the steel ball 6, and the outer side of the steel ball 6 that originally embraced the valve stem neck 41 is no longer restricted. When the outer side of the steel ball 6 is no longer restricted, the step on the upper edge of the valve stem neck 41 transmits the downward thrust of the cut-off spring 15 to the contact point with the steel ball 6 and squeezes the steel ball 6 outward through the angle force, so that the steel ball 6 enters the recessed portion above the steel ball liner boss 71, and the valve stem 4 is no longer blocked, so it performs a cutting action downward with the cut-off spring 15, thereby completing the pressure-loss cut-off.

[0089] Reset (according to the provisions of relevant standards, the cut-off valve can only be reset manually after the cut-off is triggered): Pulling the overpressure regulating cover 16 upwards can drive the pressure loss regulating rod 18 to move upwards synchronously. As the pressure loss regulating rod 18 moves upwards, the tightened end surface of the bottom of the pressure loss regulating rod 18 will compress the push spring 20 until the push spring 20 is compressed and transmits the pulling force to the indicator rod 19, so that the indicator rod 19 and the valve stem 4 are pulled upwards together, until the valve stem neck 41 returns to the corresponding position of the steel ball 6 again, and the diaphragm assembly returns to the position of contact with the spring sleeve 8 under the action of the reset spring 13, and at the same time, the steel ball seat boss 71 of the steel ball seat 7 squeezes the steel ball 6 inward again, so that the steel ball 6 returns to the initial locked state;

[0090] Then loosen the overpressure regulating cover 16, and the pushing spring 20 inside the underpressure regulating rod 18 will generate a downward thrust on the tightened end surface of the bottom inner bottom of the underpressure regulating rod 18, and this thrust will drive the underpressure regulating rod 18 and the overpressure regulating cover 16 to move downward together. After the rebound action of the pushing spring 20 is completed, you only need to lightly press the top of the overpressure regulating cover 16 with your hand to push the elastic clamping ring 23 into the semicircular ring groove on the overpressure regulating cover 16 that cooperates with the elastic clamping ring 23 to form a bite, thereby completing the reset.

[0091] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0092] The above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit the protection scope of the utility model. Obviously, the described embodiments are only some embodiments of the utility model, rather than all embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model. Although the utility model has been described in detail with reference to the above embodiments, ordinary technicians in this field can still combine, add, delete or make other adjustments to the features in the various embodiments of the utility model according to the circumstances without conflict, without making creative work, so as to obtain different other technical solutions that do not deviate from the concept of the utility model in essence, and these technical solutions also belong to the scope of protection of the utility model.

Claims

1. A built-in overpressure and pressure loss cut-off valve, characterized in that: include: case; A diaphragm (3), wherein the diaphragm (3) is installed inside the housing; A valve stem (4), the valve stem (4) being vertically mounted inside the housing; A fixing seat (5), the fixing seat (5) being sleeved on the valve stem (4), the fixing seat (5) having a plurality of horizontally arranged through holes formed on an upper portion thereof, and steel balls (6) being placed in the through holes; A steel ball liner (7), the steel ball liner (7) being mounted on the diaphragm (3), and the steel ball liner (7) being sleeved on the upper part of the fixing seat (5), the steel ball liner (7) being provided with a steel ball liner boss (71) capable of contacting the steel ball (6), and the steel ball liner (7) being provided with recessed parts on both upper and lower sides of the steel ball liner boss (71); A valve stem thin neck (41), wherein the valve stem (4) is provided with a valve stem thin neck (41) capable of abutting against the steel ball (6); A spring sleeve (8), wherein the spring sleeve (8) is installed in the upper part of the housing, and the bottom of the spring sleeve (8) is capable of abutting against the top of the diaphragm (3); An overpressure regulating spring (9), wherein the overpressure regulating spring (9) is sleeved outside the spring sleeve (8); A pressure loss regulating spring (10), wherein the pressure loss regulating spring (10) is sleeved on the outside of the valve stem (4) and is located inside the spring sleeve (8).

2. The built-in overpressure and underpressure cut-off valve according to claim 1, characterized in that: The recessed portion above the steel ball seat boss (71) is a pressure loss release zone, and the recessed portion below the steel ball seat boss (71) is an overpressure release zone.

3. The built-in overpressure and pressure loss cut-off valve according to claim 1, characterized in that: An overpressure regulating plate (11) located on the top of the overpressure regulating spring (9) is slidably mounted on the outside of the spring sleeve (8); an overpressure regulating cover (16) is rotatably mounted on the top of the shell; legs (17) are mounted on both sides of the bottom of the overpressure regulating cover (16); an arc groove (111) is formed on the overpressure regulating plate (11) for the legs (17) to pass through; the arc groove (111) and the legs (17) are slidably matched; and the overpressure regulating plate (11) is threadedly connected to the inner wall of the upper portion of the shell.

4. The built-in overpressure and pressure loss cut-off valve according to claim 3 is characterized in that: The spring sleeve (8) has an internal threaded portion with a pressure loss regulating plate (12) located at the top of the pressure loss regulating spring (10), and the overpressure regulating cover (16) has a pressure loss regulating rod (18) rotatably mounted thereon. The pressure loss regulating rod (18) extends into the housing and penetrates the pressure loss regulating plate (12), and the lower portion of the pressure loss regulating rod (18) is slidably engaged with the valve stem (4).

5. The built-in overpressure and pressure loss cut-off valve according to claim 4, characterized in that: One end of the pressure loss regulating rod (18) located in the housing is a square structure, and the pressure loss regulating plate (12) is provided with a square hole that is slidably matched with the pressure loss regulating rod (18).

6. The built-in overpressure and pressure loss cut-off valve according to claim 5, characterized in that: An opening penetrating the top of the pressure loss regulating rod (18) is provided in the pressure loss regulating rod (18), an indicator rod (19) is slidably provided in the pressure loss regulating rod (18), and the bottom of the indicator rod (19) is connected to the top of the valve stem (4).

7. The built-in overpressure and pressure loss cut-off valve according to claim 6, characterized in that: A push spring (20) is provided between the bottom of the indicating rod (19) and the inner bottom of the pressure loss regulating rod (18).

8. The built-in overpressure and underpressure cut-off valve according to claim 1, characterized in that: The diaphragm (3) is provided with a tray (21) located outside the steel ball liner (7), and the steel ball liner (7) is threadedly connected with a pin sleeve (22) that abuts against the tray (21).

9. The built-in overpressure and pressure loss cut-off valve according to claim 3, characterized in that: An elastic clamping ring (23) is installed between the overpressure regulating cover (16) and the housing.

10. The built-in overpressure and pressure loss cut-off valve according to claim 1, characterized in that: A mounting platform (24) is mounted on the bottom of the shell.

Images