Check valve, liquid intake flange, piston pump and application of check valve in liquid hydrogen pump

Abstract

Disclosed in the present application are a check valve, a liquid intake flange, a piston pump and an application of the check valve in a liquid hydrogen pump. The check valve comprises: a limiting frame, which comprises a limiting body and at least two supporting legs evenly distributed on the limiting body, wherein a gap is formed between adjacent supporting legs, and the limiting body is arranged opposite a position to be sealed; and a valve body, which can reciprocate between the limiting body and the position to be sealed. Also disclosed in the present application are the check valve, the liquid intake flange, the piston pump and the application of the check valve in the liquid hydrogen pump, which aim to solve the problem of a low response speed of a one-way valve or a check valve.

Description

Application of check valve, liquid inlet flange, piston pump and check valve in liquid hydrogen pump Technical Field

[0001] The present application relates to the technical field of drive equipment, and more specifically, to a check valve, a liquid inlet flange, a piston pump, and an application of the check valve in a liquid hydrogen pump. Background Art

[0002] A liquid hydrogen pump consists of a hydraulic end and a drive end. The hydraulic end is placed inside the liquid hydrogen storage tank and immersed in the liquid hydrogen; the drive end is placed outside the tank. The liquid hydrogen end is a hydraulic cylinder structure. During the intake of liquid hydrogen, the inlet check valve opens and the outlet check valve closes. During the compression of the liquid hydrogen, the inlet check valve closes and the outlet check valve opens. This allows the liquid hydrogen to be transported out of the tank at high pressure through the outlet check valve under the force of the piston. Existing check valves have a long travel distance and a relatively complex structure, resulting in slow response speed.

[0003] Therefore, a check valve, a liquid inlet flange, a piston pump and an application of the check valve in a liquid hydrogen pump are needed to solve the above problems.

[0004] Summary of the Invention

[0005] In view of this, the purpose of this application is to propose a check valve, a liquid inlet flange, a piston pump and an application of the check valve in a liquid hydrogen pump to solve the problem of slow response speed of the one-way valve or check valve.

[0006] Based on the above purpose, the present application provides a check valve, comprising:

[0007] A limiting frame, comprising a limiting body and at least two supporting legs evenly distributed on the limiting body, with gaps being provided between adjacent supporting legs; the limiting body is arranged opposite to the position to be sealed;

[0008] A valve body is capable of reciprocating between the limiting body and the position to be sealed.

[0009] Optionally, a flange is provided at one end of the supporting leg away from the limiting body, and a fixing piece is provided on the flange, and the fixing piece is used to connect the flange to the outer periphery of the position to be sealed.

[0010] Optionally, the limiting body is provided with at least one through hole penetrating along the axial direction.

[0011] Optionally, the valve body includes a main body and an overlapping edge formed around the main body, the main body includes a sealing surface, the sealing surface protrudes toward one side of the position to be sealed and can at least partially enter the position to be sealed, and the overlapping edge can overlap the edge of the position to be sealed.

[0012] Optionally, the thickness of the center of the main body is greater than the thickness of the overlapping edge.

[0013] Optionally, the valve body further includes a pressure-bearing surface, the sealing surface is arranged opposite to the pressure-bearing surface, and the distance between the sealing surface and the pressure-bearing surface first gradually increases to the center of the main body and then gradually decreases.

[0014] Optionally, a gap is provided between the overlapping edge and the supporting leg.

[0015] Optionally, at least two evenly distributed moving channels are provided on the overlapping edge, and the moving channels are gap-matched with the supporting legs.

[0016] The present application also provides a liquid inlet flange, comprising:

[0017] Such as the check valve mentioned above;

[0018] The liquid inlet flange body is provided with a liquid inlet channel, and the check valve is connected to the liquid inlet flange body and can open and close the liquid inlet channel.

[0019] The present application also provides a piston pump, comprising:

[0020] Such as the check valve mentioned above;

[0021] A liquid inlet flange body, wherein the liquid inlet flange body is provided with a liquid inlet channel; the check valve is connected to the liquid inlet flange body;

[0022] A hydraulic cylinder, the liquid inlet flange body is connected to the hydraulic cylinder, the hydraulic cylinder includes an accommodating cavity, and the liquid inlet channel is communicated with the accommodating cavity;

[0023] The piston is movably arranged in the accommodating chamber and can be moved close to or away from the liquid inlet flange body; the check valve can open and close the liquid inlet channel to connect or cut off the liquid inlet channel and the accommodating chamber.

[0024] In addition, optionally, an avoidance hole is provided at one end of the piston facing the check valve, and the check valve at least partially enters the avoidance hole.

[0025] The present application also provides an application of the above-mentioned check valve in a liquid hydrogen pump.

[0026] As can be seen from the above, the check valve, liquid inlet flange, piston pump, and check valve provided by this application in the liquid hydrogen pump have the following advantages compared to the prior art: When the above-mentioned check valve is used, the fluid force pushes the valve body away from the position to be sealed. When the hydraulic cylinder is filled with liquid, the limit frame limits the maximum movement position of the valve body, shortening and reducing the distance the valve body moves in the hydraulic cylinder. Moreover, when the hydraulic cylinder stops filling with liquid, the valve body returns to the position to be sealed due to gravity; the pressure in the hydraulic cylinder can be transmitted to the valve body through liquid hydrogen, and the valve body provides sufficient sealing pressure under the combined action of downward pressure and gravity to achieve sealing and non-return functions. In addition, the check valve has a simple structure, which reduces the difficulty of driving and improves the response speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above features and technical advantages of the present application will become clearer and easier to understand through the following description of its embodiments in conjunction with the accompanying drawings.

[0028] FIG1 is a schematic diagram of a closed state of a check valve used in the first embodiment of the present application.

[0029] FIG2 is a schematic diagram of the check valve shown in FIG1 in an open state.

[0030] FIG3 is a schematic diagram of the check valve and the piston shown in FIG1 in a coordinated state.

[0031] FIG. 4 is a schematic diagram of the valve body shown in FIG. 1 .

[0032] FIG5 is a side view of the valve body shown in FIG4 .

[0033] FIG. 6 is a schematic diagram of the limiting frame shown in FIG. 1 .

[0034] FIG. 7 is a side view of the limiting frame shown in FIG. 6 .

[0035] FIG8 is a schematic diagram of the cooperation state of the check valve and the piston used in the second embodiment of the present application.

[0036] FIG9 is a schematic diagram of the valve body shown in FIG8 .

[0037] FIG10 is a schematic diagram of the check valve and the piston in the closed state used in the third embodiment of the present application.

[0038] FIG11 is a schematic diagram of the open state of the check valve shown in FIG10 .

[0039] FIG12 is a schematic diagram of the cooperation state of the check valve and the piston shown in FIG10 .

[0040] FIG13 is a schematic diagram of the valve body shown in FIG10 .

[0041] FIG14 is a side view of the valve body shown in FIG13.

[0042] Wherein the accompanying drawings are:

[0043] 1. Liquid inlet flange body; 1-1. First liquid inlet flange body; 2. Hydraulic cylinder; 3. Piston; 4. Valve body; 4-1. First valve body; 4-2. Second valve body; 5. Limiting frame; 51. Limiting body; 52. Bolt hole; 53. Through hole. DETAILED DESCRIPTION

[0044] To make the objectives, technical solutions, and advantages of this application more clearly understood, the present application is further described below in conjunction with specific embodiments and with reference to the accompanying drawings. Identical parts are denoted by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings. The terms "inward" and "outward" refer to directions toward or away from the geometric center of a particular component, respectively.

[0045] FIG1 is a schematic diagram of the closed state of the check valve used in the first embodiment of the present application. FIG2 is a schematic diagram of the open state of the check valve shown in FIG1. ​​FIG3 is a schematic diagram of the check valve and the piston shown in FIG1 in cooperation. FIG4 is a schematic diagram of the valve body shown in FIG1. ​​FIG5 is a side view of the valve body shown in FIG4. FIG6 is a schematic diagram of the limit frame shown in FIG1. ​​FIG7 is a side view of the limit frame shown in FIG6. As shown in FIG1 to FIG7, the check valve includes a limit frame 5 and a valve body 4.

[0046] The limiting frame 5 includes a limiting body and at least two supporting legs evenly distributed on the limiting body, with gaps provided between adjacent supporting legs; the limiting body is arranged relative to the position to be sealed; the limiting frame 5 is connected to the outer periphery of the position to be sealed, and is used to limit the maximum movement displacement of the valve body 4. If the limiting frame 5 is connected to the outer periphery of the position to be sealed through the supporting legs, so that the limiting frame 5 cover is arranged outside the position to be sealed, the installation position of the supporting legs will not destroy the sealing effect, and there is a gap between adjacent supporting legs for liquid hydrogen to pass through, which facilitates the flow of liquid hydrogen.

[0047] The valve body 4 can reciprocate between the limiter and the position to be sealed. Usually, the valve body 4 is arranged in the limiter frame 5, and the valve body 4 abuts the position to be sealed to achieve the sealing effect; the valve body 4 moves away from the position to be sealed to achieve the unsealing effect.

[0048] The liquid inlet flange body 1 is connected between the hydraulic cylinder 2 and the liquid hydrogen storage tank. It is provided with a liquid inlet channel, comprising an inlet and an outlet. The inlet communicates with the liquid hydrogen storage tank, and the outlet communicates with the hydraulic cylinder 2. If the unsealed position is the outlet of the liquid inlet channel, a check valve is provided at the unsealed position. During liquid inlet, the check valve opens due to fluid force as the piston 3 moves upward, drawing in liquid hydrogen. Specifically, when the hydraulic cylinder 2 begins to draw in liquid hydrogen, the piston 3 within the hydraulic cylinder 2 is at the relatively lower end of the hydraulic cylinder 2 and begins to move upward. The internal pressure of the hydraulic cylinder 2 gradually decreases until the fluid force pushes the valve body 4 upward, releasing the unsealed unsealed position. The limiter 5 limits the maximum displacement of the valve body 4, and the liquid hydrogen passes through the valve body 4 and is automatically pressed into the hydraulic cylinder 2. When the piston 3 reaches the top end of the hydraulic cylinder 2, the liquid hydrogen no longer flows into the hydraulic cylinder 2, and the valve body 4 falls back under the action of gravity, sealing the unsealed position. When the piston 3 moves downward to compress the liquid hydrogen in the hydraulic cylinder 2, the pressure in the hydraulic cylinder 2 is transferred to the valve body 4 by the liquid hydrogen, so that sufficient sealing pressure is generated between the valve body 4 and the position to be sealed, thereby achieving sealing and non-return functions.

[0049] With this check valve, fluid force pushes valve body 4 away from the sealing position. When the hydraulic cylinder is filled with fluid, the limiter 5 limits the maximum travel of valve body 4, shortening and minimizing the distance valve body 4 can move within hydraulic cylinder 2. Furthermore, when hydraulic cylinder 2 stops filling, valve body 4 returns to the sealing position due to gravity. Pressure within hydraulic cylinder 2 is transmitted to valve body 4 via liquid hydrogen. The combined effects of downward pressure and gravity provide sufficient sealing pressure, achieving both sealing and non-return functions. The check valve also features a simple structure, reducing actuation complexity and improving response speed.

[0050] In one embodiment of the present application, the limit frame 5 and / or the valve body 4 are made of a metal material resistant to hydrogen corrosion, thereby improving corrosion resistance and extending the service life of the check valve.

[0051] In one embodiment of the present application, the limiting frame 5 includes multiple (such as 6 to 8) supporting legs, and the multiple supporting legs are evenly distributed along the circumferential direction of the limiting body 51. The limiting body 51 and the supporting legs are enclosed to form a limiting cavity. The limiting cavity is a non-closed cavity, and there is a gap between adjacent supporting legs for fluid to pass through.

[0052] Optionally, a flange is provided at one end of the support leg away from the stopper, and a fixing member is provided on the flange for connecting the flange to the outer periphery of the location to be sealed. The provision of the flange increases the contact area between the support leg and the outer periphery of the location to be sealed, thereby increasing the installation stability of the stopper 5.

[0053] In one embodiment of the present application, the flange extends toward a side away from the limiting cavity to avoid blocking the position to be sealed. A bolt hole 52 is provided on the flange. The fixing parts include but are not limited to common parts such as bolts and screws. The fixing parts are passed through the bolt hole 52 and fix the flange.

[0054] Optionally, the stopper is provided with at least one through-hole extending axially therethrough. Typically, through-hole 53 is positioned opposite the position to be sealed, with valve body 4 positioned between them. Liquid hydrogen can act on valve body 4 through through-hole 53, providing downward pressure thereon. Furthermore, a portion of piston 3 can enter the stopper 5 through through-hole 53, allowing the check valve and piston 3 to engage within a narrow range, thereby reducing the volume requirement for hydraulic cylinder 2.

[0055] In one embodiment of the present application, the diameter of the through hole 53 is larger than the diameter of the position to be sealed, and the diameter of the valve body 4 is larger than the diameter of the through hole 53 .

[0056] In one embodiment of the present application, a through hole 53 is provided on a stopper 51, a stopper cavity cover is provided outside the location to be sealed, and support legs are connected to the outer periphery of the location to be sealed via flanges. The valve body 4 reciprocates within the stopper cavity. The stopper cavity communicates with the location to be sealed and is also connected to the hydraulic cylinder 2 via the through hole 53. The valve body 4 reciprocates within the stopper cavity, reaching its maximum movement position where it abuts the stopper 51. Using this stopper frame 5 results in a relatively simple and compact structure, occupies little space, and is easy to install.

[0057] Optionally, the valve body includes a main body and an overlapping edge formed around the main body. The main body includes a sealing surface that protrudes toward a side of a position to be sealed. When the position to be sealed is a port of a liquid inlet channel, the sealing surface is capable of at least partially entering the port of the liquid inlet channel, and the overlapping edge is capable of overlapping an edge of the position to be sealed. The main body overlaps the edge of the position to be sealed via the peripheral overlapping edge, and the main body is sealed to the position to be sealed via the sealing surface. The sealing surface partially enters the position to be sealed, thereby ensuring a sealing effect through insertion sealing and achieving self-positioning during reciprocating movement.

[0058] In one embodiment of the present application, the valve body 4 is in the shape of a disc protruding to one side, the protruding portion is the main body, the protruding surface of the protruding portion is the sealing surface, and the area surrounding the protruding portion is the overlapping edge.

[0059] Optionally, the thickness of the center of the main body is greater than the thickness of the overlapping edge. The thickness of the main body can generally be consistent or inconsistent. When the thickness of the main body is inconsistent, the thickness of the center of the main body is the largest, and the thickness of the main body is set according to the pressure it can withstand. The thickness of the overlapping edge is generally consistent, and the thickness of the overlapping edge is set to meet the sealing and structural strength requirements. By setting different thicknesses, that is, when the overlapping edge overlaps the edge of the position to be sealed, increasing the thickness of the center of the main body can ensure the sealing performance of the valve body 4 at the position to be sealed, achieving self-positioning during reciprocating movement, while reducing the thickness of the overlapping edge to meet the sealing performance requirements and avoid deformation.

[0060] In one embodiment of the present application, the thickness of the center of the main body is 1.5-3 times the thickness of the overlapping edges.

[0061] Optionally, the valve body 4 also includes a pressure-bearing surface, and the sealing surface and the pressure-bearing surface are arranged opposite to each other, and the distance between the sealing surface and the pressure-bearing surface first gradually increases to the center of the main body and then gradually decreases. The pressure-bearing surface is used to withstand the downward pressure provided by liquid hydrogen or the piston 3. The pressure-bearing surface can be a horizontal surface, which is arranged flush with the upper surface of the overlapping edge, or the sealing surface and the pressure-bearing surface are both arc-shaped surfaces protruding to the same side. It should be ensured that the distance between the sealing surface and the pressure-bearing surface first gradually increases to the center of the main body and then gradually decreases to ensure that the thickness of the center of the main body is the largest. By setting the thickness and shape of the valve body 4, the sealing performance of the valve body 4 to the position to be sealed can be guaranteed, and self-positioning during reciprocating movement can be achieved, which helps to achieve gravity self-positioning of the valve body 4, so that the center of the main body can enter the position to be sealed to achieve plug-in sealing.

[0062] In one embodiment of the present application, the main body includes a pressure-bearing surface and a sealing surface arranged in opposite directions. The pressure-bearing surface is arranged opposite to the through hole 53, and the sealing surface protrudes toward the side away from the pressure-bearing surface. Liquid hydrogen can act on the pressure-bearing surface through the through hole 53.

[0063] Figure 8 is a schematic diagram of the check valve and piston used in the second embodiment of the present application. Figure 9 is a schematic diagram of the valve body shown in Figure 8. As shown in Figures 8 and 9, valve body 4 adopts a first valve body 4-1, the shape of which is different from that of valve body 4 in the first embodiment.

[0064] The first valve body 4-1 has a symmetrical structure. The closer to the center of the main body, the greater the distance between the sealing surface and the pressure-bearing surface, i.e., the greater the thickness. The closer to the edge of the main body, the smaller the distance between the sealing surface and the pressure-bearing surface, i.e., the thinner the thickness. In one embodiment of the present application, the pressure-bearing surface of the first valve body 4-1 is a flat surface, and the sealing surface of the first valve body 4-1 is an arcuate surface.

[0065] Optionally, a gap is provided between the overlapping edge and the support leg. This gap should not affect the reciprocating movement of the valve body 4, while ensuring effective positioning of the valve body 4 to prevent significant movement. By providing this gap, the overlapping edge does not rub against the support leg during movement, reducing the difficulty of driving the valve body 4 and improving the response speed of the valve body 4.

[0066] Optionally, the overlapping edge is provided with at least two evenly distributed movement channels, which are clearance-matched with the support legs. The movement channels are sleeved onto the support legs, allowing the overlapping edge to reciprocate along the support legs through the movement channels. The support legs provide guidance for the overlapping edge, and the clearance fit reduces friction between the overlapping edge and the support legs, ensuring the response speed of the valve body 4.

[0067] In one embodiment of the present application, if the supporting legs are cylindrical, the movable channel may be in the shape of a waist hole.

[0068] Figure 10 is a schematic diagram of the check valve and piston in the closed state used in the third embodiment of the present application. Figure 11 is a schematic diagram of the check valve shown in Figure 10 in the open state. Figure 12 is a schematic diagram of the check valve and piston in the coordinated state shown in Figure 10. Figure 13 is a schematic diagram of the valve body shown in Figure 10. Figure 14 is a side view of the valve body shown in Figure 13. As shown in Figures 10 to 14, the valve body 4 adopts a second valve body 4-2, and the shape of the second valve body 4-2 is different from the shape of the valve body 4 in the first embodiment. The liquid inlet flange body 1 adopts a first liquid inlet flange body 1-1, which is different from the shape of the liquid inlet flange body 1 in the first embodiment.

[0069] The main body and its two side edges are integrally molded, with a smooth transition between the main body and the edges, rather than a distinct bend. The second valve body 4-2 is symmetrically constructed. The closer to the center of the main body, the greater the distance between the sealing surface and the pressure-bearing surface, i.e., the thicker it is. The closer to the edges, the smaller the distance between the sealing surface and the pressure-bearing surface, and the smaller the distance between the overlapping edges and the pressure-bearing surface, i.e., the thinner it is.

[0070] The first liquid inlet flange body 1-1 is provided with a liquid inlet channel, which includes an inlet end and an outlet end. The inlet end is connected to the liquid hydrogen storage tank, and the outlet end is connected to the hydraulic cylinder 2. If the position to be sealed is the outlet end of the liquid inlet channel, a check valve is provided at the position to be sealed. In order to achieve a good match with the second valve body 4-2, the end face of the outlet end is provided with an arcuate surface. The arcuate surface is a gradient surface, that is, the diameter of the arcuate surface gradually increases from the inlet end side to the outlet end side; and the arcuate surface coincides with the edge of the second valve body 4-2. That is, when the second valve body 4-2 is in the closed state, the main body enters the liquid inlet channel, and the edge overlaps the arcuate surface, realizing the self-positioning function under the action of gravity and effectively sealing the outlet end.

[0071] In addition, the arc surface at the outlet end is inclined downward, and solid impurities in liquid hydrogen are not easily deposited and retained on the arc surface, which can realize the self-cleaning function, so that the second valve body 4-2 can achieve efficient and reliable sealing.

[0072] Generally, in order to ensure that the valve body 4 can be sealed and unsealed normally and realize the self-positioning function, the distance between the two ends of the second valve body 4-2 (that is, the distance between the two side edges) should be greater than the diameter of the inlet channel, and the distance between the two ends of the second valve body 4-2 should be less than the distance between the limit frame 5 and the place to be sealed.

[0073] The following further introduces the use of the check valve.

[0074] The liquid inlet flange body 1 is connected between the hydraulic cylinder 2 and the liquid hydrogen storage tank. A liquid inlet channel is provided on the liquid inlet flange body 1. The liquid inlet channel includes an inlet end and an outlet end. The inlet end communicates with the liquid hydrogen storage tank, and the outlet end communicates with the hydraulic cylinder 2. If the position to be sealed is the outlet end of the liquid inlet channel, a check valve is provided at the position to be sealed. A limit frame 5 is provided outside the position to be sealed. The limit frame 5 is connected to the outside of the position to be sealed via support legs, so that the limit body is arranged opposite to the position to be sealed, and the valve body 4 abuts the position to be sealed via a sealing surface. During liquid inflow, the check valve opens by fluid force as piston 3 moves upward to draw in liquid hydrogen. That is, when hydraulic cylinder 2 begins to absorb liquid hydrogen, piston 3 inside hydraulic cylinder 2 is at the relatively lower end of hydraulic cylinder 2 and begins to move upward. The internal pressure of hydraulic cylinder 2 gradually decreases until valve body 4 moves upward, and the sealing surface of valve body 4 leaves the waiting-to-seal position, achieving the unsealed waiting-to-seal position. The limiter limits the maximum displacement of valve body 4, reducing the travel distance of valve body 4. After passing through valve body 4, liquid hydrogen is automatically pressed into hydraulic cylinder 2 from the gap between the support legs. When piston 3 reaches the top end of hydraulic cylinder 2, liquid hydrogen no longer flows into hydraulic cylinder 2, and valve body 4 falls back under the action of gravity, sealing the waiting-to-seal position. When the piston 3 moves downward to compress the liquid hydrogen in the hydraulic cylinder 2, the liquid hydrogen filled with pressure in the hydraulic cylinder 2 is transferred to the valve body 4 through the through hole 53 and the gap between the support legs. Under the action of the valve body 4's own weight and the downward pressure, sufficient sealing pressure is generated between the valve body 4 and the position to be sealed, realizing the sealing and non-return functions.

[0075] The present application also provides a liquid inlet flange, comprising: a check valve and a liquid inlet flange body 1.

[0076] The liquid inlet flange includes the check valve as described above. The check valve can adopt the check valve in any of the above embodiments, which will not be described in detail here.

[0077] The liquid inlet flange body 1 is provided with a liquid inlet channel. A check valve is connected to the liquid inlet flange body 1 and can open and close the liquid inlet channel. The liquid inlet flange body 1 is connected between the hydraulic cylinder 2 and the liquid hydrogen storage tank. The liquid inlet channel includes an inlet and an outlet. The inlet is connected to the liquid hydrogen storage tank, and the outlet is connected to the hydraulic cylinder 2. Liquid inlet refers to liquid hydrogen provided by the liquid hydrogen storage tank entering the liquid inlet flange body 1 through the inlet and entering the hydraulic cylinder 2 through the outlet.

[0078] The check valve includes a stop frame 5 and a valve body 4. The stop frame 5 is connected to the liquid inlet flange body 1. The valve body 4 is arranged between the liquid inlet flange body 1 and the stop frame 5. The stop frame 5 is used to limit the maximum movement distance of the valve body 4. The liquid inlet channel includes an inlet end and an outlet end. The valve body 4 is arranged on the side of the outlet end. When the valve body 4 abuts the outlet end, the liquid inlet channel is closed and liquid in and out. When the valve body 4 moves away from the outlet end and toward the side where the stop frame 5 is located, the liquid inlet channel is opened and liquid can enter the liquid inlet channel.

[0079] By adopting the liquid inlet flange, the check valve has a simple structure and a fast response speed, and can quickly open and close the liquid inlet channel of the liquid inlet flange body.

[0080] In one embodiment of the present application, a liquid inlet channel is provided in the axial direction of the liquid inlet flange body 1 , and a liquid outlet channel is provided in the radial direction of the liquid inlet flange body 1 , and the liquid outlet channel is communicated with the liquid inlet channel.

[0081] In one embodiment of the present application, the liquid inlet flange body 1 is detachably connected to the hydraulic cylinder 2, and / or the liquid inlet flange body 1 is detachably connected to the liquid hydrogen storage tank.

[0082] The present application also provides a piston pump, comprising: a check valve, a hydraulic cylinder 2, a piston 3 and a liquid inlet flange body 1.

[0083] The piston pump includes the check valve as described above. The check valve can adopt the check valve in any of the above embodiments, which will not be described in detail here.

[0084] The liquid inlet flange body 1 is provided with a liquid inlet channel; the check valve is connected to the liquid inlet flange body 1; the liquid inlet flange body 1 can adopt the liquid inlet flange body 1 in any of the above embodiments, which will not be repeated here.

[0085] The liquid inlet flange body 1 is connected to the hydraulic cylinder 2. The hydraulic cylinder 2 includes a receiving chamber, and the liquid inlet channel is connected to the receiving chamber. The hydraulic cylinder 2 includes a top end and a bottom end that are oppositely arranged, and the receiving chamber is arranged between the top end and the bottom end. The liquid inlet flange body 1 is connected to the bottom end of the hydraulic cylinder 2.

[0086] The piston 3 is movably disposed within the accommodating chamber and can be moved toward or away from the liquid inlet flange body 1. The check valve can open and close the liquid inlet passage, thereby connecting or disconnecting the liquid inlet passage from the accommodating chamber. The piston 3 is movably connected within the accommodating chamber, reciprocating between the top and bottom ends. When the piston 3 moves away from the liquid inlet flange body 1, the check valve opens the liquid inlet passage, connecting the liquid inlet passage with the accommodating chamber and allowing liquid inflow. When the piston 3 moves toward the liquid inlet flange body 1, the check valve closes the liquid inlet passage, disconnecting the liquid inlet passage from the accommodating chamber and stopping liquid inflow.

[0087] The liquid inlet flange body 1 is connected between the hydraulic cylinder 2 and the liquid hydrogen storage tank. The liquid inlet flange body 1 is provided with a liquid inlet channel. The liquid inlet channel includes an inlet end and an outlet end. The inlet end is connected to the liquid hydrogen storage tank, and the outlet end is connected to the hydraulic cylinder 2. The check valve is provided at the outlet end of the liquid inlet channel. When liquid is introduced, the piston 3 moves toward the top end, and liquid hydrogen enters the liquid inlet channel from the inlet end. The fluid force pushes the check valve away from the outlet end, and the liquid inlet channel is connected to the accommodating chamber, and liquid enters the accommodating chamber. When the piston 3 moves to the top end, the liquid inlet stops. Under the action of gravity, the check valve resets to the outlet end and forms a seal, cutting off the connection between the liquid inlet channel and the accommodating chamber. When the piston 3 moves toward the bottom end, the pressure in the hydraulic cylinder 2 is transmitted to the check valve through the liquid hydrogen, providing downward pressure on the reset check valve, generating sufficient sealing pressure to achieve the sealing and non-return functions. Using the above-mentioned piston pump, when liquid is introduced, the piston 3 moves upward, and the fluid force pushes the check valve to move away from the to-be-sealed position, connecting the liquid inlet channel and the accommodating chamber. When liquid inflow stops, the check valve automatically resets to the sealed position due to gravity, blocking the liquid inlet channel and the accommodating chamber. As piston 3 moves downward, the pressure within hydraulic cylinder 2 is transmitted to the check valve via the liquid hydrogen. The combined force of downward pressure and gravity generates sufficient sealing pressure, achieving both sealing and non-return functions. The check valve also features a simple structure, reducing actuation difficulty and improving response speed.

[0088] Optionally, a clearance hole is provided on the end of the piston facing the check valve, into which the check valve at least partially enters. When the piston 3 moves toward the check valve, the check valve's stopper 5 can enter the clearance hole. This piston 3 achieves a more compact structure. The stopper 5 enters the piston 3, leaving the piston 3 with less clearance at the end of compression, which helps increase volumetric efficiency and improve the performance of the piston pump.

[0089] In one embodiment of the present application, a protrusion is provided on the end surface of the piston 3 facing the stop frame 5, and a groove is provided on the end surface of the liquid inlet flange body 1 facing the piston 3 to cooperate with the protrusion, so that the protrusion can enter the groove. The edge of the protrusion away from the piston 3 is provided with a smooth chamfer, and the bottom of the groove structure is also provided with a smooth chamfer.

[0090] In one embodiment of the present application, an avoidance hole is provided in the middle of the raised structure, the diameter of the avoidance hole is larger than the diameter of the limit frame 5, the avoidance hole cover is provided on the outside of the limit frame 5, the limit frame 5 can enter the avoidance hole, the bottom of the avoidance hole is provided with a smooth chamfer, and the corners of the limit frame 5 are provided with a smooth chamfer.

[0091] In one embodiment of the present application, the relief hole in piston 3 is annular, i.e., the relief hole divides the raised structure into two edge portions and a central raised portion. A through-hole 53 is provided in stop frame 5, and the raised portion has a smaller diameter than through-hole 53. When stop frame 5 enters the relief hole of piston 3, the edge portion enters the space surrounding stop frame 5, and the raised portion enters through-hole 53. The mutual encroachment between piston 3 and stop frame 5 results in a smaller clearance between piston 3 and stop frame 5 at the end of compression, which helps increase volumetric efficiency and improve the performance of the piston pump.

[0092] In one embodiment of the present application, the valve body of the check valve includes a pressure-bearing surface, and the end surface of the protrusion away from the piston 3 can match the pressure-bearing surface. For example, when the pressure-bearing surface is an arc-shaped, the end surface of the drive head is a matching arc-shaped; for example, when the pressure-bearing surface is a plane, the end surface of the drive head is a plane.

[0093] The present application also provides an application of the aforementioned check valve in a liquid hydrogen pump. The application method can adopt any of the aforementioned embodiments, which will not be described in detail here.

[0094] From the above description and practice, it can be seen that the check valve, liquid inlet flange, piston pump and check valve provided by this application in the liquid hydrogen pump have the following advantages compared with the existing technology: when the above-mentioned check valve is used, the fluid force pushes the valve body 4 away from the position to be sealed. When the hydraulic cylinder 2 is filled with liquid, the limit frame 5 limits the maximum movement position of the valve body 4, shortening and reducing the distance the valve body 4 moves in the hydraulic cylinder 2. Moreover, when the hydraulic cylinder 2 stops filling with liquid, the valve body 4 returns to the position to be sealed due to gravity; the pressure in the hydraulic cylinder 2 can be transmitted to the valve body 4 through liquid hydrogen. Under the combined action of downward pressure and gravity, the valve body 4 provides sufficient sealing pressure to achieve sealing and non-return functions. In addition, the check valve has a simple structure, which reduces the difficulty of driving and improves the response speed.

[0095] Those skilled in the art should understand that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the scope of the present application should be included in the scope of protection of the present application.

Claims

1. A check valve, characterized in that: include: A limiting frame, the limiting frame comprising a limiting body and at least two supporting legs evenly distributed on the limiting body, with gaps being provided between adjacent supporting legs; the limiting body is arranged opposite to the position to be sealed; A valve body is capable of reciprocating between the limiting body and the position to be sealed.

2. The check valve according to claim 1, characterized in that: A flange is arranged at one end of the supporting leg away from the limiting body, and a fixing piece is arranged on the flange. The fixing piece is used to connect the flange to the outer periphery of the position to be sealed.

3. The check valve according to claim 2, characterized in that: The limiting body is provided with at least one through hole penetrating along the axial direction.

4. The check valve according to any one of claims 1 to 3, characterized in that: The valve body includes a main body and an overlapping edge formed around the main body, the main body includes a sealing surface, the sealing surface protrudes toward one side of the position to be sealed and can at least partially enter the position to be sealed, and the overlapping edge can overlap the edge of the position to be sealed.

5. The check valve according to claim 4, characterized in that: The thickness of the center of the body is greater than the thickness of the overlapping edges.

6. The check valve according to claim 5, characterized in that: The valve body further comprises a pressure-bearing surface, the sealing surface is arranged opposite to the pressure-bearing surface, and the distance between the sealing surface and the pressure-bearing surface first gradually increases to the center of the main body and then gradually decreases.

7. The check valve according to claim 4, characterized in that: A gap is provided between the overlapping edge and the supporting leg.

8. The check valve according to claim 4, characterized in that: At least two evenly distributed moving channels are arranged on the overlapping edge, and the moving channels are gap-matched with the supporting legs.

9. A liquid inlet flange, characterized in that: include: The check valve according to any one of claims 1 to 8; The liquid inlet flange body is provided with a liquid inlet channel, and the check valve is connected to the liquid inlet flange body and can open and close the liquid inlet channel.

10. A piston pump, characterized in that: include: The check valve according to any one of claims 1 to 8; A liquid inlet flange body, wherein the liquid inlet flange body is provided with a liquid inlet channel; the check valve is connected to the liquid inlet flange body; A hydraulic cylinder, the liquid inlet flange body is connected to the hydraulic cylinder, the hydraulic cylinder includes a containing cavity, and the liquid inlet channel is communicated with the containing cavity; The piston is movably arranged in the accommodating chamber and can be close to or away from the liquid inlet flange body; the check valve can open and close the liquid inlet channel to connect or cut off the liquid inlet channel and the accommodating chamber.

11. The piston pump according to claim 10, characterized in that: An escape hole is provided at one end of the piston facing the check valve, and the check valve at least partially enters the escape hole.

12. Use of the check valve according to any one of claims 1 to 8 in a liquid hydrogen pump.

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