A high pressure stop check valve

Abstract

The present application discloses a high-pressure stop check valve, which solves the technical problem of the prior art that the check valve is not completely turned as the working pressure increases. The high-pressure stop check valve disclosed in this embodiment is provided with a control groove connected to the inlet on the valve head. After the fluid enters the control groove along the first through hole, it will act on the valve head together with the fluid in the inlet, thereby generating a downward medium balancing force, which can make full use of the working pressure. The greater the working pressure, the greater the medium balancing force, and the stronger the sealing reliability. By adjusting the difference between the diameter of the control groove and the inlet diameter, the extrusion sealing force of the valve head on the inlet can be adjusted, so that the medium balancing force is greater than the required pressure of the sealing surface and less than the allowable pressure of the sealing surface, thereby ensuring that when the outlet pressure is greater than or equal to the inlet pressure, the valve head can always be squeezed at the inlet of the valve body, so that the inlet is in a closed state, thereby improving the reliability of the check valve.

Description

Technical Field

[0001] The present application belongs to the technical field of stop check valves, and in particular relates to a high-pressure stop check valve. Background Art

[0002] With the continuous improvement of equipment technical indicators, higher requirements are put forward for the working pressure, small size and light weight, operating performance, safety, reliability and other general quality characteristics of valves used in high-pressure air systems. It is difficult to meet these requirements with existing technologies.

[0003] In accordance with the process of increasing working pressure and comprehensive performance requirements, the main seal of the high-pressure air stop check valve has gone through the technical stages of conventional structure cone hard seal, ordinary nylon sealing gasket flat soft seal with balance cavity, MC nylon sealing gasket flat soft seal with balance cavity, and polyimide sealing gasket flat soft seal with balance cavity.

[0004] As the working pressure of valves is further increased to 60MPa, it is impossible to achieve the technical index requirements of small size and light weight, low operating torque, high reliability, etc. through the above technical path, resulting in the phenomenon of incomplete check valves during operation. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides a high-pressure stop check valve.

[0006] The technical solution adopted to achieve the purpose of this application is that the present invention discloses a high-pressure stop check valve, comprising:

[0007] A valve body, wherein the valve body comprises an inlet, an outlet and an operating channel, wherein the inlet, the outlet and the operating channel converge at one point, and the inlet is coaxially arranged with the operating channel;

[0008] a lower valve stem, the lower valve stem being movable along the operating channel, the lower valve stem being provided with a contraction portion along one end thereof facing the inlet; and

[0009] A valve head, wherein the valve head is slidably matched with the operating channel, and the valve head is slid to close or open the inlet. The valve head is provided with a first through hole and a control groove for matching with the contraction portion, and the control groove is sealed and matched with the contraction portion. The lower valve stem can push the valve head to move toward the inlet, and after the lower valve stem moves upward a preset distance, it can drive the valve head to move upward synchronously, and the two ends of the first through hole are respectively connected with the control groove and the inlet.

[0010] Further, one end of the valve head facing the inlet is configured to be conical, and the valve body is provided with a corresponding matching inclined surface at the inlet.

[0011] Furthermore, the connecting sleeve is connected to the valve head, and the connecting sleeve is arranged outside the lower valve stem, so that after the lower valve stem moves upward by a preset distance, it can drive the connecting sleeve and the valve head to move upward synchronously.

[0012] Furthermore, a first protrusion is provided in the middle of the lower valve stem, and a movable groove is provided on the connecting sleeve. The first protrusion is located in the movable groove so that after the lower valve stem moves upward a preset distance, it can drive the connecting sleeve and the valve head to move upward synchronously.

[0013] Furthermore, it also includes a balancing piston, which is wrapped around the lower valve stem, and a force reduction chamber is formed between the top wall of the balancing piston and the valve body. The balancing piston can move along the axis of the lower valve stem, and a second through hole is provided on the lower valve stem. The first end of the second through hole is connected to the control groove, and the lower valve stem is moved to connect or disconnect the second end of the second through hole with the force reduction chamber.

[0014] Further, the outlet extends to the bottom of the balancing piston.

[0015] Furthermore, when the lower valve stem moves upward, it can push the balancing piston to move so as to reduce the force reduction chamber above the balancing piston.

[0016] Furthermore, a second protrusion is provided on the lower valve stem, the second protrusion is located above the first protrusion, the diameter of the second protrusion is smaller than the diameter of the first protrusion, and the diameter of the second protrusion is larger than the inner diameter of the balancing piston.

[0017] Further, projections of the first through hole and the second through hole in the vertical direction at least partially overlap.

[0018] Furthermore, two ends of the spring component are respectively connected to the valve body and the valve head, and the spring component enables the valve head to have a tendency to move toward the inlet.

[0019] It can be seen from the above technical solution that the high-pressure stop check valve disclosed in this embodiment is provided with a control groove connected to the inlet on the valve head. After the fluid enters the control groove along the first through hole, it will act on the valve head together with the fluid in the inlet, thereby generating a downward medium balancing force, which can make full use of the working pressure. The greater the working pressure, the greater the medium balancing force, and the stronger the sealing reliability. By adjusting the difference between the diameter of the control groove and the inlet diameter, the extrusion sealing force of the valve head on the inlet can be adjusted, so that the medium balancing force is greater than the required pressure of the sealing surface and less than the allowable pressure of the sealing surface, thereby ensuring that when the outlet pressure is greater than or equal to the inlet pressure, the valve head can always be squeezed at the inlet of the valve body, so that the inlet is in a closed state, thereby improving the reliability of the check valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the high-pressure stop check valve in the first state in an embodiment of the present application;

[0021] Figure 2 This is a schematic diagram of the high-pressure stop check valve in the second state in an embodiment of the present application;

[0022] Figure 3 This is a schematic diagram of the high-pressure stop check valve in the third state in the embodiment of the present application;

[0023] Figure 4 This is a schematic diagram of the high-pressure stop check valve in the fourth state in the embodiment of the present application;

[0024] Figure 5 is a schematic diagram of the valve body;

[0025] Figure 6 for Figure 5 A partial enlarged schematic diagram of

[0026] Figure 7 is a schematic diagram of the valve head;

[0027] Figure 8 is a schematic diagram of the lower valve stem;

[0028] Fig. 9 is a schematic diagram of a connecting sleeve;

[0029] Fig.10 is a schematic diagram of the bushing;

[0030] Fig.11 is a schematic diagram of a balancing piston;

[0031] Fig.12 is a schematic diagram of the upper valve stem;

[0032] Fig.13 is a schematic diagram of a transmission nut;

[0033] Fig.14 It is a schematic diagram of the valve head control structure;

[0034] Fig.15 is a schematic diagram of the outer surface of the valve body;

[0035] Fig.16 Schematic diagram of the outer surface of the transmission nut

[0036] Description of reference numerals:

[0037] 1-valve body, 101-inlet, 102-outlet, 103-operating channel, 104-matching inclined surface, 105-check line, 106-cut-off line, 2-valve head, 201-control groove, 202-first through hole, 203-sealing cone, 3-lower valve stem, 301-contraction part, 302-first protrusion, 303-second protrusion, 304-second through hole, 4-connecting sleeve, 401-movable groove, 402-first opening, 5 balancing piston, 501-force reduction chamber, 6-spring member, 7-bushing, 701-force reduction groove, 702-second opening, 8-valve frame, 9-stop gasket, 10-fixing nut, 11-stud stud, 12-transmission nut, 1201-fixing groove, 1202-thread groove, 1203-indicating structure, 13-upper valve stem, 14-handwheel. DETAILED DESCRIPTION

[0038] In order to enable technicians in the technical field to which the present application belongs to understand the present application more clearly, the technical solution of the present application is described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0039] See also Figure 1 Only Fig.16 In the embodiment of the present application, the high-pressure stop check valve includes a valve body 1, a lower valve stem 3 and a valve head 2. The valve body 1 includes an inlet 101, an outlet 102 and an operating channel 103. The inlet 101, the outlet 102 and the operating channel 103 converge at one place, and the inlet 101 is coaxially arranged with the operating channel 103. The lower valve stem 3 can move along the operating channel 103, and a contraction portion 301 is provided along the end of the lower valve stem 3 facing the inlet 101. The valve head 2 is slidably matched with the operating channel 103, and the sliding valve head 2 closes or opens the inlet 101. The valve head 2 is provided with a first through hole 202 and a pressure control groove 201 for matching with the contraction portion 301. The control groove 201 is sealed with the contraction portion 301. The lower valve stem 3 can push the valve head 2 to move toward the inlet 101, and the lower valve stem 3 can drive the valve head 2 to move upward synchronously after moving upward by a preset distance. The two ends of the first through hole 202 are respectively connected with the control groove 201 and the inlet 101.

[0040] Through the above embodiments, the present application has the following beneficial effects or advantages: the high-pressure stop check valve disclosed in the present embodiment is provided with a control groove 201 connected to the inlet 101 on the valve head 2. After the fluid enters the control groove 201 along the first through hole 202, it will act on the valve head 2 together with the fluid in the inlet 101, thereby generating a downward medium balancing force, which can make full use of the working pressure. The greater the working pressure, the greater the medium balancing force, and the stronger the sealing reliability. By adjusting the difference between the diameter of the control groove 201 and the diameter of the inlet 101, the extrusion sealing force of the valve head 2 on the inlet 101 can be adjusted, so that the medium balancing force is greater than the required pressure of the sealing surface and less than the allowable pressure of the sealing surface, thereby ensuring that when the pressure of the outlet 102 is greater than or equal to the pressure of the inlet 101, the valve head 2 can always be squeezed at the inlet 101 of the valve body 1, so that the inlet 101 is in a closed state, thereby improving the reliability of the check valve.

[0041] Specifically, the diameter of the control groove 201 can be adjusted at the beginning of production and processing. Before processing, the diameter of the inlet 101 is confirmed in advance, and then the optimal diameter of the control groove 201 can be calculated according to the maximum pressure difference between the inlet and outlet 102. The pressure of the valve head 2 on the valve body 1 at the inlet 101 is calculated as follows: (inlet 101 diameter - control groove 201 diameter) * pressure difference between the inlet 101 and the outlet 102 = force.

[0042] In the standardized production process, it is somewhat difficult to change the diameter of the inlet 101 on the valve body 1, so it is possible to consider setting an inclined surface at the inlet 101 of the valve body 1. Figures 5 to 7 , by setting the matching bevel 104, the effect of changing the diameter of the inlet 101 can also be achieved. After testing, after setting the matching bevel 104 at the inlet 101 of the valve body 1, the diameter of the inlet 101 in the above formula will be replaced by the middle diameter of the bevel, that is, thereafter, only the matching bevel 104 needs to be processed to obtain the desired optimal diameter. Correspondingly, the end of the valve head 2 facing the inlet 101 can be set to a cone shape, and the inclination of the valve head 2 at the cone can be adjusted according to the inclination of the matching bevel 104 to achieve the best sealing effect. Among them, the adjustment methods for the middle diameter of the matching bevel 104 include but are not limited to the following methods: 1. Adjust the width of the matching bevel 104; 2. Adjust the inclination angle of the matching bevel 104.

[0043] Of course, providing the inclined surface at the inlet 101 of the valve body 1 is only one implementation method in this embodiment. In other implementation methods, the valve head 2 having a larger diameter than the inlet 101 may be used to squeeze the valve body 1 to close the inlet 101. In this case, the squeezing force of the valve head 2 on the valve body 1 only needs to be adjusted by adjusting the diameter of the control groove 201. After the matching inclined surface 104 is provided at the inlet 101 of the valve body 1, the middle diameter of the inclined surface and the diameter of the control groove 201 can be adjusted at the same time, which is more convenient and quick when adjusting.

[0044] In order to further improve the reliability of the check function, a spring member 6 may be provided in the valve body 1, and the two ends of the spring member 6 are respectively connected to the valve body 1 and the valve head 2, and the spring member 6 makes the valve head 2 have a tendency to move toward the inlet 101. In this embodiment, the medium balance force is mainly used, and the elastic force of the spring member 6 is used as an auxiliary to apply a downward force to the valve head 2, so as to ensure that during the check process, when the pressure of the outlet 102 is greater than or equal to the pressure of the inlet 101, the valve head 2 can always abut against the inlet 101 to close the inlet 101.

[0045] See also Figure 5 The valve body 1 is provided with an inlet 101, an outlet 102 and an operating channel 103. The inlet 101 and the operating channel 103 are coaxially arranged, the outlet 102 can be arranged perpendicular to the inlet 101, the operating channel 103 can be arranged in a stepped shape, and the diameter of the end of the operating channel 103 away from the inlet 101 is larger.

[0046] The valve head 2 can slide up and down in the operating channel 103 to open or close the inlet 101. The bottom of the valve head 2 is conical, and a control groove 201 is arranged on the top of the valve head 2. The bottom of the first through hole 202 and the control groove 201 extend to the bottom wall of the valve head 2 to connect the control groove 201 with the inlet 101.

[0047] The lower valve stem 3 is provided with a second protrusion 303, a first protrusion 302 and a contraction portion 301 from top to bottom, the diameter of the second protrusion 303 is larger than the diameter of the lower valve stem 3 itself, the diameter of the first protrusion 302 is larger than the diameter of the second protrusion 303, the diameter of the contraction portion 301 is smaller than the diameter of the first protrusion 302, and the diameter of the contraction portion 301 is adapted to the diameter of the control groove 201. The contraction portion 301 is sealed with the control groove 201, that is, a sealing ring can be provided on the side wall of the control groove 201 or the contraction portion 301, so that the fluid will not escape from the gap between the lower valve stem 3 and the valve head 2 after entering the control groove 201 along the first through hole 202.

[0048] A connecting sleeve 4 can be arranged outside the valve head 2, and the connecting sleeve 4 and the valve head 2 can be detachably matched. The bottom of the connecting sleeve 4 is connected to the top of the valve head 2, and a movable groove 401 is arranged near the top of the connecting sleeve 4, and a first opening 402 is arranged at the top of the connecting sleeve 4, and the first opening 402 penetrates the top wall of the connecting sleeve 4. The first protrusion 302 of the lower valve stem 3 is located in the movable groove 401, and the height of the first protrusion 302 is less than the height of the movable groove 401, so that the lower valve stem 3 will not directly drive the connecting sleeve 4 to move when it moves a certain distance, and after the lower valve stem 3 moves upward by a preset distance, it will drive the connecting sleeve 4 and the valve head 2 to move upward synchronously. The diameter of the second protrusion 303 can be equal to the diameter of the first opening 402 to prevent the fluid at the outlet 102 from flowing into the movable groove 401.

[0049] It should be noted that in this embodiment, the maximum diameter of the valve head 2, the maximum diameter of the connecting sleeve 4 and the maximum diameter of the lower valve stem 3 are all smaller than the minimum diameter of the operating channel 103. Therefore, the fluid at the outlet 102 will fill around the valve head 2, the connecting head and the lower valve stem 3.

[0050] In the above implementation of the present embodiment, the connecting sleeve 4 and the valve head 2 are detachably matched in a threaded or snap-fit ​​manner. In other implementations, the valve head 2 and the connecting sleeve 4 can also be processed in an integral molding manner. At this time, the first protrusion 302 can be delivered into the movable groove 401 in other ways. For example, the first protrusion 302 can be set as a separate point protrusion and set as a telescopic structure. After the lower valve stem 3 is extended into the movable groove 401, the first protrusion 302 pops out, which can also ensure that the lower valve stem 3 can drive the valve head 2 to move upward together.

[0051] The bushing 7 is installed on the valve body 1 at the position of the larger diameter of the operating channel 103. The bushing 7 and the valve body 1 are detachably matched to facilitate the assembly of the valve head 2 and the lower valve stem 3, and the bushing 7 and the valve body 1 are sealed. The bottom of the bushing 7 is provided with a force reduction groove 701, and the top wall of the bushing 7 is provided with a second opening 702. The second opening 702 penetrates the top wall of the bushing 7 to communicate with the force reduction groove 701.

[0052] The lower valve stem 3 is slidably matched with the second opening 702, and the bushing 7 can be used to guide the lower valve stem 3. The lower valve stem 3 is provided with a second through hole 304, and the first end of the second through hole 304 is connected to the control groove 201. The lower valve stem 3 is moved to connect or disconnect the second end of the second through hole 304 with the force reduction groove 701. The lower valve stem 3 is sealed with the second opening 702 to prevent fluid from leaking from the second opening 702.

[0053] A balancing piston 5 is also provided between the lower valve stem 3 and the bushing 7, and the balancing piston 5 is wrapped around the lower valve stem 3. The inner wall of the balancing piston 5 is sealed with the lower valve stem 3, and the outer wall of the balancing piston 5 is sealed with the side wall of the force reduction chamber 501, and the balancing piston 5 can move up and down relative to the bushing 7 and the lower valve stem 3. A force reduction chamber 501 can be formed by the top wall of the balancing piston 5, the outer wall of the lower valve stem 3, the side wall of the force reduction groove 701, and the bottom wall of the force reduction groove 701. When the second through hole 304 is connected with the force reduction chamber 501, the fluid in the inlet 101 can flow into the force reduction chamber 501. In this embodiment, the first through hole 202 and the second through hole 304 can be coaxially arranged or the first through hole 202 and the second through hole 304 can have at least a partially overlapping portion in the vertical direction to ensure that when the high-pressure stop check valve is in a cut-off state, the second through hole 304 can still be connected to the first through hole 202, thereby smoothly introducing the fluid into the force reduction chamber 501.

[0054] Among them, the medium balancing force exerted by the fluid on the control groove 201 is the same. After the fluid enters the force reduction chamber 501, the fluid will exert a downward medium balancing force on the balancing bushing 7, and its magnitude is equal to (the diameter of the inlet 101-the diameter of the force reduction chamber 501)*the pressure difference between the inlet 101 and the outlet 102. By utilizing this downward medium balancing force, the resultant force on the lower valve stem 3 can be minimized, thereby reducing the operating torque of the entire valve.

[0055] Since the fluid at the outlet 102 is always filled in the connection sleeve 4 and around the lower valve stem 3 , after the balancing piston 5 is provided, the fluid at the outlet 102 will also be filled in the bottom and around the balancing piston 5 .

[0056] See 1 to Figure 4 The high-pressure stop check valve disclosed in this application has multiple working states:

[0057] like Figure 1 At this time, the high-pressure stop check valve is in the cut-off state, and the pressure at the inlet 101 is greater than the pressure at the outlet 102. At this time, the balancing piston 5 moves downward under the action of the inlet 101 pressure and abuts against the connecting sleeve 4. Its extrusion force can further squeeze the valve head 2, thereby making the seal more reliable.

[0058] like Figure 2 At this time, the high-pressure stop check valve is in the cut-off state, and the pressure at the outlet 102 is greater than the pressure at the inlet 101. At this time, the balancing piston 5 moves upward under the action of the pressure at the outlet 102 to completely fill the force reduction chamber 501.

[0059] like Figure 3At this time, it is the non-return state of the high-pressure stop check valve, and at this time the pressure of the inlet 101 is greater than the pressure of the outlet 102. The valve head 2 moves upward under the push of the inlet 101 pressure so that the fluid in the inlet 101 can flow out of the outlet 102 smoothly.

[0060] like Figure 4 At this time, it is the non-return state of the high-pressure stop check valve, and the pressure of the outlet 102 is greater than the pressure of the inlet 101. At this time, the fluid at the inlet 101 flows into the control groove 201 and exerts a downward medium balancing force on the valve head 2, so that the valve head 2 closes the inlet 101.

[0061] See also Figure 1 The valve frame 8, stop gasket 9, fixing nut 10, stud 11 and other structures are also arranged on the top of the valve body 1. The valve frame 8, stop gasket 9, fixing nut 10 and stud 11 are arranged in sequence along the height direction of the valve body 1. The inner diameter of the valve frame 8 can be larger than the outer diameter of the bushing 7. The valve frame 8 can form a certain limit on the bushing 7 and improve the stability of the connection of the bushing 7.

[0062] The high-pressure stop check valve disclosed in the present application also includes a hand wheel 14, an upper valve stem 13 and a transmission nut 12. The transmission nut 12 is slidably matched with the valve body 1, and the transmission nut 12 can move up and down along the height direction of the valve body 1. The transmission nut 12 is connected to the lower valve stem 3, and when the transmission nut 12 moves up and down, it can drive the lower valve stem 3 to move together. Figure 12 to Figure 14 In this embodiment, a fixing groove 1201 can be provided at the bottom of the driving nut 12, and then a fixing block for cooperating with the fixing groove 1201 can be provided at the top of the lower valve stem 3. After the fixing block is clamped into the fixing groove 1201, the driving nut 12 can drive the lower valve stem 3 to move together when it moves up and down. Among them, the fixing groove 1201 can be set in a shape such as a T-slot or a dovetail groove. Of course, setting the fixing groove 1201 and the fixing block to connect the driving nut 12 and the lower valve stem 3 is only one embodiment of this embodiment. In other embodiments, the driving nut 12 and the lower valve stem 3 can also be connected by other methods such as threaded connection.

[0063] The upper valve stem 13 is rotatably connected to the valve body 1, the bottom of the upper valve stem 13 is provided with an external thread, the top of the drive nut 12 is provided with a thread groove 1202, the upper valve stem 13 and the drive nut 12 are threadedly matched, when the upper valve stem 13 rotates, the drive nut 12 can move up and down through the thread. The hand wheel 14 is installed on the top of the upper valve stem 13, and the hand wheel 14 is used to drive the upper valve stem 13 to rotate, which is more convenient to use.

[0064] See also Fig.15 and Fig.16At least two identification lines are arranged outside the valve body 1, which are a cut-off line 106 and a check line 105, respectively. The cut-off line 106 is located below the check line 105. A window can be provided next to the identification line on the valve body 1, or the valve body 1 can be provided with a transparent structure at the position of the identification line, and an indication structure 1203 is provided outside the driving nut 12 to identify the working state of the high-pressure cut-off check valve.

[0065] When the transmission nut 12 drives the lower valve stem 3 to move downward and presses the valve head 2 against the inlet 101, the indicator structure 1203 on the transmission nut 12 is aligned with the cut-off line 106, indicating that the high-pressure cut-off check valve is in the cut-off state. When the transmission nut 12 drives the lower valve stem 3 to move upward so that the first protrusion 302 pushes the balance piston 5 to completely fill the force reduction chamber 501, the indicator structure 1203 on the transmission nut 12 is aligned with the check line 105, indicating that the high-pressure cut-off check valve is in the non-return state.

[0066] The high pressure stop check valve disclosed in this embodiment is controlled as follows:

[0067] When the high-pressure stop check valve needs to be operated to the stop state, the hand wheel 14 is rotated clockwise to drive the upper valve stem 13 to rotate, and the external thread on the upper valve stem 13 and the internal thread on the drive nut 12 rotate relative to each other, thereby driving the drive nut 12 to move downward, and then driving the lower valve stem 3 and the valve head 2 to move downward, so that the sealing cone surface 203 of the valve head 2 is combined with the matching inclined surface 104 of the valve body 1 to form a sealing pair, completing the two-way stop state operation of the valve. During the operation, the fluid enters the force reduction chamber 501 above the balance piston 5 through the first through hole 202 on the valve head 2 and the second through hole 304 on the lower valve stem 3, generating a downward medium pressure balancing force, which completely or partially offsets the upward medium force on the sealing cone surface 203 of the valve head 2, thereby reducing the operating torque.

[0068] When it is necessary to operate the high-pressure stop check valve to the check state, the hand wheel 14 is rotated counterclockwise to drive the upper valve stem 13 to rotate, and the external thread on the upper valve stem 13 and the internal thread on the transmission nut 12 rotate relative to each other, thereby driving the transmission nut 12 to move upward, and then driving the lower valve stem 3 to move upward. When the indicating structure 1203 on the transmission nut 12 is aligned with the check line 105 on the valve body 1, the check state operation of the valve is completed.

[0069] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0070] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A high pressure stop check valve, characterized in that: include: A valve body (1), the valve body (1) comprising an inlet (101), an outlet (102) and an operating channel (103), the inlet (101), the outlet (102) and the operating channel (103) converging at one point, and the inlet (101) and the operating channel (103) being coaxially arranged; a lower valve stem (3), the lower valve stem (3) being movable along the operating channel (103), the lower valve stem (3) being provided with a contraction portion (301) along one end of the lower valve stem (3) facing the inlet (101); and A valve head (2), wherein the valve head (2) is slidably matched with the operating channel (103), and the valve head (2) is slid to close or open the inlet (101). The valve head (2) is provided with a first through hole (202) and a control groove (201) for matching with the contraction portion (301), and the control groove (201) is sealed and matched with the contraction portion (301). The lower valve stem (3) can push the valve head (2) to move toward the inlet (101), and after the lower valve stem (3) moves upward a preset distance, it can drive the valve head (2) to move upward synchronously, and the two ends of the first through hole (202) are respectively connected with the control groove (201) and the inlet (101).

2. The high-pressure stop check valve according to claim 1, characterized in that: One end of the valve head (2) facing the inlet (101) is arranged in a conical shape, and the valve body (1) is provided with a corresponding matching inclined surface (104) at the inlet (101).

3. The high-pressure stop check valve according to claim 1, characterized in that: It also includes a connecting sleeve (4), which is connected to the valve head (2), and the connecting sleeve (4) is sleeved outside the lower valve stem (3), so that after the lower valve stem (3) moves upward a preset distance, it can drive the connecting sleeve (4) and the valve head (2) to move upward synchronously.

4. The high-pressure stop check valve according to claim 3, characterized in that: A first protrusion (302) is provided in the middle of the lower valve stem (3), and a movable groove (401) is provided on the connecting sleeve (4). The first protrusion (302) is located in the movable groove (401) so that after the lower valve stem (3) moves upward a preset distance, it can drive the connecting sleeve (4) and the valve head (2) to move upward synchronously.

5. The high-pressure stop check valve according to claim 4, characterized in that: It also includes a balancing piston (5), which is wrapped around the lower valve stem (3), and a force reduction chamber (501) is formed between the top wall of the balancing piston (5) and the valve body (1). The balancing piston (5) can move along the axis of the lower valve stem (3), and a second through hole (304) is provided on the lower valve stem (3). The first end of the second through hole (304) is connected to the control groove (201), and the lower valve stem (3) is moved to connect or disconnect the second end of the second through hole (304) with the force reduction chamber (501).

6. The high-pressure stop check valve according to claim 5, characterized in that: The outlet (102) extends to the bottom of the balancing piston (5).

7. The high-pressure stop check valve according to claim 5, characterized in that: When the lower valve stem (3) moves upward, it can push the balancing piston (5) to move so as to reduce the force reduction chamber (501) above the balancing piston (5).

8. The high-pressure stop check valve according to claim 7, characterized in that: A second protrusion (303) is provided on the lower valve stem (3), and the second protrusion (303) is located above the first protrusion (302). The diameter of the second protrusion (303) is smaller than the diameter of the first protrusion (302), and the diameter of the second protrusion (303) is larger than the inner diameter of the balancing piston (5).

9. The high-pressure stop check valve according to claim 5, characterized in that: The projections of the first through hole (202) and the second through hole (304) in the vertical direction at least partially overlap.

10. The high-pressure stop check valve according to claim 1, characterized in that: It also comprises a spring component (6), the two ends of which are respectively connected to the valve body (1) and the valve head (2), and the spring component (6) enables the valve head (2) to have a tendency to move towards the inlet (101).

Images