Hydrogen liquid drive pump, hydrogen compressor and hydrogenation skid-mounted station

Abstract

The invention discloses a hydrogen liquid-driven pump, a hydrogen compressor and a hydrogenation skid-mounted station, and the hydrogen liquid-driven pump comprises an oil cylinder which comprises an oil cylinder piston rod; the first isolation cylinder and the second isolation cylinder are respectively arranged at two ends of the oil cylinder; the first end air cylinder and the second end air cylinder are located at the two ends of the hydrogen liquid drive pump respectively. A first air cylinder piston rod of the first end air cylinder is movably connected with the first end of the oil cylinder piston rod and located in the first isolation cylinder, and a second air cylinder piston rod of the second end air cylinder is movably connected with the second end of the oil cylinder piston rod and located in the second isolation cylinder. According to the technical scheme, the first isolation cylinder and the second isolation cylinder are additionally arranged, so that the phenomenon of oil-gas mixing is effectively prevented; the long piston rod is divided into three sections, the two ends of the oil cylinder piston rod are movably connected with the first air cylinder piston rod and the second air cylinder piston rod respectively, the problem that coaxiality of the long piston rod is difficult to guarantee is solved, and the problems that abrasion of a sealing assembly of the piston rod is aggravated, and gas leaks are solved.

Description

Technical Field

[0001] This application belongs to the field of compressor technology, specifically relating to a hydrogen liquid-driven pump, a hydrogen compressor, and a hydrogen refueling skid-mounted station. Background Technology

[0002] The liquid-driven pump is the core component of a liquid-driven hydrogen compressor. It uses hydraulic pressure to drive the reciprocating motion of a cylinder piston to achieve hydrogen compression. With the rapid increase in global hydrogen supply and consumption, higher requirements are being placed on the displacement of liquid-driven hydrogen compressors, which is limited by the cylinder volume and piston stroke.

[0003] One existing technical solution involves reducing the cylinder radius and using multiple pumps in parallel compression to ensure displacement. This reduces the difficulty of coaxiality control but increases costs. Another existing technical solution does not design an independent isolation chamber, thus reducing the overall length of the hydraulic pump and correspondingly reducing the piston rod length. It also uses a floating piston design, with the piston head and piston rod floating together, allowing the piston head to float radially. During reciprocating motion, this enables self-adjustment of the coaxiality between the piston and cylinder, mitigating piston seal wear. However, without an isolation chamber, long-term operation can easily lead to oil-gas mixing, contaminating high-purity hydrogen. Furthermore, while this solution solves the coaxiality problem between the piston and piston rod, it does not guarantee the coaxiality of a long piston rod, leading to increased piston rod seal wear during operation and potentially causing higher hydrogen leakage rates. Summary of the Invention

[0004] The purpose of this application is to provide a hydrogen-liquid-driven pump, a hydrogen compressor, and a hydrogen refueling skid-mounted station to solve problems such as oil-gas mixing and gas leakage caused by easy wear of the piston rod sealing components.

[0005] To achieve the above objectives, this application provides a hydrogen-liquid driven pump, the hydrogen-liquid driven pump comprising: Hydraulic cylinder, including hydraulic cylinder piston rod; The first isolation cylinder and the second isolation cylinder are respectively located at both ends of the oil cylinder; The first end cylinder and the second end cylinder are located at the two ends of the hydrogen-liquid driven pump, respectively. Wherein, the first cylinder piston rod of the first end cylinder is movably connected to the first end of the oil cylinder piston rod and is located in the first isolation cylinder, and the second cylinder piston rod of the second end cylinder is movably connected to the second end of the oil cylinder piston rod and is located in the second isolation cylinder.

[0006] In some embodiments, one end of the first cylinder piston rod is provided with a first protrusion extending axially, and the first end of the hydraulic cylinder piston rod is provided with a first groove with an axial opening. The first protrusion is inserted into the first groove and is used to limit the relative rotation between the hydraulic cylinder piston rod and the first cylinder piston rod.

[0007] In some embodiments, a clearance fit is formed between the first protrusion and the first groove.

[0008] In some embodiments, a radially penetrating pin hole is formed between the first protrusion and the first end of the cylinder piston rod, and a first pin is inserted into the radially penetrating pin hole. A radial clearance is formed between the first pin and the hole wall of the radially penetrating pin hole, so that a radial floating connection is formed between the cylinder piston rod and the first cylinder piston rod.

[0009] In some embodiments, the hydrogen-liquid pump further includes a first collar, which is sleeved on the connection portion between the first cylinder piston rod and the first end of the oil cylinder piston rod, and both ends of the first pin abut against the inner wall of the first collar.

[0010] In some embodiments, a clamping limiting ring is provided at the axial end of the first collar.

[0011] In some embodiments, the connection between the first cylinder piston rod and the first end of the oil cylinder piston rod is located inside the first isolation cylinder, and the hydrogen-liquid pump further includes a position switch for monitoring the position of the connection, the position switch being disposed between the outer wall of the first collar and the first isolation cylinder.

[0012] In some embodiments, in the first end cylinder and the second end cylinder, the piston rod of the first cylinder is movably connected to the first cylinder piston of the first end cylinder, and the piston rod of the second cylinder is movably connected to the second cylinder piston of the second end cylinder.

[0013] A second aspect of this application provides a hydrogen compressor, the hydrogen compressor including a gas delivery pipe and a hydrogen liquid-driven pump as described above, the gas delivery pipe being disposed outside the hydrogen liquid-driven pump and connected to the first end cylinder and the second end cylinder.

[0014] A third aspect of this application provides a hydrogen refueling skid-mounted station, including a hydrogen compressor as described above.

[0015] Through the above technical solution, a first isolation cylinder and a second isolation cylinder are respectively added between the first end cylinder and the second end cylinder and the oil cylinder, which effectively prevents the phenomenon of oil-gas mixing and will not cause pollution to high-purity hydrogen. The oil cylinder piston rod, the first cylinder piston rod and the second cylinder piston rod are set, dividing the long piston rod into three sections. The two ends of the oil cylinder piston rod are respectively movably connected to the first cylinder piston rod and the second cylinder piston rod, which solves the problem of difficulty in ensuring the coaxiality of the long piston rod and avoids problems such as accelerated wear of the piston rod sealing components and gas leakage.

[0016] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without any inventive effort. In the drawings: Figure 1 This is a first-view structural schematic diagram of the hydrogen-liquid driven pump of this application; Figure 2 This is a second-view structural schematic diagram of the hydrogen-liquid driven pump of this application; Figure 3 This is an exploded structural diagram of the connection between the first cylinder piston rod and the oil cylinder piston rod in this application. Figure 4 for Figure 2 A magnified view of a portion of point F in the middle; Figure 5 for Figure 1 A magnified view of a portion of point E in the middle; Figure 6 This is a schematic diagram illustrating the working principle of the hydrogen-liquid driven pump of this application.

[0018] Explanation of reference numerals in the attached figures Detailed Implementation

[0019] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0020] A hydrogen-liquid-driven pump and a hydrogen compressor according to this application are described below with reference to the accompanying drawings.

[0021] like Figures 1 to 2As shown, this application provides a hydrogen-liquid driven pump, which includes a hydraulic cylinder 1, a first isolation cylinder 2, a second isolation cylinder 3, a first end cylinder 4, and a second end cylinder 5. The hydraulic cylinder 1 includes a hydraulic cylinder piston rod 11; the first isolation cylinder 2 and the second isolation cylinder 3 are respectively disposed at both ends of the hydraulic cylinder 1; the first end cylinder 4 and the second end cylinder 5 are respectively located at both ends of the hydrogen-liquid driven pump. Specifically, the first cylinder piston rod 41 of the first end cylinder 4 is movably connected to the first end of the hydraulic cylinder piston rod 11, and the movable connection portion is located within the first isolation cylinder 2; the second cylinder piston rod 51 of the second end cylinder 5 passes through the second isolation cylinder 3 and is movably connected to the second end of the hydraulic cylinder piston rod 11, and the movable connection portion is located within the second isolation cylinder 3.

[0022] In the hydrogen-liquid driven pump of this application, by adding a first isolation cylinder 2 and a second isolation cylinder 3 between the first end cylinder 4 and the second end cylinder 5 and the oil cylinder 1 respectively, the phenomenon of oil-gas mixing is effectively prevented, and the high-purity hydrogen is not contaminated. The oil cylinder piston rod 11, the first cylinder piston rod 41 and the second cylinder piston rod 51 are provided, and the long piston rod is divided into multiple segments. The two ends of the oil cylinder piston rod 11 are movably connected to the first cylinder piston rod 41 and the second cylinder piston rod 51 respectively, which solves the problem of the difficulty in ensuring the coaxiality of the long piston rod and avoids problems such as accelerated wear of the piston rod sealing components and gas leakage.

[0023] In some embodiments, the hydrogen-liquid pump further includes a first connecting component 6 and a second connecting component 7, wherein the first cylinder piston rod 41 and the first end of the oil cylinder piston rod 11 are movably connected through the first connecting component 6, and the second cylinder piston and the second end of the oil cylinder piston rod 11 are movably connected through the second connecting component 7.

[0024] It should be noted that, in this application, unless otherwise stated, directional terms such as "upper" and "lower" refer to... Figure 2 The direction in which it is inserted is parallel to the first pin 61; "front" and "back" refer to the direction in which it is inserted. Figure 2 The direction in which the first pin 61 is inserted is perpendicular to the direction of insertion; "left" and "right" refer to the direction in which the pin is inserted. Figure 2 In the direction parallel to the length of the cylinder piston rod 11, with the cylinder piston rod 11 as the center, the first cylinder piston rod 41 is on the left and the second cylinder piston rod 51 is on the right.

[0025] like Figure 3 As shown, one end of the first cylinder piston rod 41 is provided with a first protrusion 42 extending axially. The first end of the hydraulic cylinder piston rod 11 is provided with a first groove 111 with an axial opening. The first protrusion 42 is inserted into the first groove 111 and is used to limit the relative rotation between the hydraulic cylinder piston rod 11 and the first cylinder piston rod 41.

[0026] Specifically, such as Figure 4As shown, the first protrusion 42 is inserted axially into the first groove 111, and there is a gap between the first protrusion 42 and the radial inner wall of the first groove 111, allowing the first protrusion 42 to float radially. It can be understood that the connection between the first protrusion 42 and the first groove 111 is a clearance fit. During operation, there is a radial gap at the connection between the first cylinder piston rod 41 and the oil cylinder piston rod 11, allowing them to float up and down. The alignment deviation of the first cylinder piston rod 41 and the oil cylinder piston rod 11 during operation can be effectively absorbed or compensated.

[0027] In some embodiments, the first connecting assembly 6 includes a first pin 61. A radially penetrating pin hole is formed between the first protrusion 42 and the first end of the cylinder piston rod 11, and the first pin 61 is inserted into the radially penetrating pin hole, the first pin 61 penetrating radially through the first protrusion 42 and the first end of the cylinder piston rod 11. Figure 5 As shown, a radial clearance is formed between the first pin 61 and the wall of the radial pin hole, so that a radial floating connection is formed between the oil cylinder piston rod 11 and the first cylinder piston rod 41.

[0028] Specifically, when the piston head of the hydraulic cylinder 1 moves to the right, it pushes the piston rod 11 of the hydraulic cylinder to move to the right, and at the same time pulls the piston rod 41 of the first cylinder to move to the right. At this time, due to the setting of the first pin 61 in the radial pin hole, there is a radial gap of 0.2-1mm between the first pin 61 and the hole wall of the radial pin hole. The piston rod 41 of the first cylinder is pulled by the piston rod 11 of the hydraulic cylinder. When the piston rod 41 of the first cylinder is pulled, the inner wall of its radial pin hole contacts the first pin 61. The piston rod 41 of the first cylinder can be moved and adjusted in the up and down direction, and can also be moved and adjusted in the back and forth direction. During this process, the piston rod 41 of the first cylinder and the piston rod 11 of the hydraulic cylinder automatically adjust to be concentric. Similarly, when the piston head of the hydraulic cylinder 1 moves to the left, it pushes the piston rod 11 to the left. The first cylinder piston rod 41 is pushed by the piston rod 11. When the first cylinder piston rod 41 is pushed, the inner wall of its radial pin hole contacts the first pin 61. The first cylinder piston rod 41 can move and adjust in the vertical direction, and it can also move and adjust in the forward and backward direction. During this process, the first cylinder piston rod 41 and the hydraulic cylinder piston rod 11 automatically adjust to be concentric. During operation, the first cylinder piston rod 41 can float in two mutually perpendicular directions of freedom. The alignment deviation between the first cylinder piston rod 41 and the hydraulic cylinder piston rod 11 can be effectively absorbed or compensated, solving the problem of difficulty in ensuring the coaxiality of a long piston rod.

[0029] Furthermore, the first connecting assembly 6 also includes a first collar 62, which is sleeved on the connecting portion between the first cylinder piston rod 41 and the first end of the oil cylinder piston rod 11. Both ends of the first pin 61 abut against the inner wall of the first collar 62 to restrict the position of the first pin 61 and prevent the first pin 61 from falling off radially.

[0030] Furthermore, the first connecting component 6 also includes a clamp limiting ring 63, and the clamp limiting ring 63 is provided at the axial end of the first ring 62 to limit the first ring 62.

[0031] Specifically, the clamp limiting ring 63 is nested within the first end of the cylinder piston rod 11 and located at the axial outer end of the first sleeve ring 62, used to restrict the axial movement of the first sleeve ring 62. In this embodiment, the first end of the cylinder piston rod 11 is configured as a stepped shaft, and the shoulder of the shaft can limit the first sleeve ring 62 on one side. Of course, the clamp limiting ring 63 can also be provided on both sides of the first sleeve ring 62 for limiting.

[0032] In some embodiments, the connection portion between the first cylinder piston rod 41 and the first end of the oil cylinder piston rod 11 is located inside the first isolation cylinder 2. The hydrogen-liquid pump also includes a position switch for monitoring the position of the connection portion. The position switch is disposed between the outer wall of the first collar 62 and the first isolation cylinder 2.

[0033] The reciprocating motion of a hydrogen-liquid pump requires precise reversing control, and position switches (usually proximity switches or limit switches) are the "command signals" for achieving this automatic reversing. They trigger the reversing of the cylinder piston head by monitoring the displacement of the piston rod or related connecting parts.

[0034] Specifically, the first ring 62 has an annular boss 621 on its circumferential side, which serves as a trigger (such as a magnetic ring, metal sensing block, or cam). At each end of the first isolation cylinder 2, corresponding to the end point of the first ring 62's stroke, a position switch (left position switch and right position switch) is installed. Hydraulic oil enters the cylinder, driving the cylinder piston head to push the cylinder piston rod 11 to the right, simultaneously driving the first cylinder piston rod 41 and the second cylinder piston rod 51 to the right. When the first ring 62 reaches the predetermined position on the right end, its trigger enters the sensing area of ​​the right position switch. The right position switch immediately detects this signal and sends an electrical signal to the pump's main control system. Upon receiving the signal from the right position switch, the control system immediately drives a... An electrically controlled directional valve actuates; the directional valve changes the flow path of the hydraulic oil, cutting off the original oil circuit that drove the piston to the right and establishing a new oil circuit that drives the piston head of the cylinder to move to the left; after the direction of the piston head of the cylinder changes, the piston head of the cylinder pushes the piston rod 11 to the left, and at the same time drives the piston rod 41 of the first cylinder and the piston rod 51 of the second cylinder to start moving to the left; when the first collar 62 moves to the predetermined position on the left end, the trigger approaches the left position switch; the left position switch sends a signal, and the control system drives the directional valve to reverse again, and the piston rod 41 of the first cylinder and the piston rod 51 of the second cylinder start moving to the right again. This cycle repeats continuously, realizing automatic and continuous reciprocating motion.

[0035] Of course, the position switch can also be set in the second isolation cylinder 3. Its specific working principle is the same as that of the position switch installed in the first isolation cylinder 2, and will not be described in detail here.

[0036] In some embodiments, in the first end cylinder 4 and the second end cylinder 5, the first cylinder piston rod 41 is movably connected to the first cylinder piston of the first end cylinder 4, and the second cylinder piston rod 51 is movably connected to the second cylinder piston of the second end cylinder 5.

[0037] Specifically, the first cylinder piston is sleeved on the first end of the first cylinder piston rod 41 and forms a clearance fit with the first end. There is a radial clearance between the first cylinder piston and the first end of the first cylinder piston rod 41. During operation, the positions of the first cylinder piston and the first cylinder piston rod 41 can be adjusted by vertical floating. The alignment deviation can be effectively absorbed or compensated, which can counteract the problem of misalignment between the first cylinder piston and the first cylinder piston rod 41 and alleviate the problem of seal wear at the first cylinder piston. The second cylinder piston is sleeved on the second end of the second cylinder piston rod 51, forming a clearance fit. There is a radial clearance between the second cylinder piston and the second end of the second cylinder piston rod 51. During operation, the position of the second cylinder piston and the second cylinder piston rod 51 can be adjusted vertically, effectively absorbing or compensating for any misalignment. This counteracts the misalignment problem between the second cylinder piston and the second cylinder piston rod 51, and alleviates the problem of seal wear at the second cylinder piston.

[0038] In this embodiment, the two ends of the first cylinder piston rod 41 are movably connected to the first end of the oil cylinder piston rod 11 and the first cylinder piston, respectively. The two ends of the second cylinder piston rod 51 are movably connected to the second end of the oil cylinder piston rod 11 and the second cylinder piston rod, respectively. Both ends of the first cylinder piston rod 41 and the second cylinder piston rod 51 are provided with movable connections to form a double floating structure. During operation, the alignment deviation of the first cylinder piston rod 41 and the second cylinder piston rod 51 can be effectively absorbed or compensated, preventing the formation of a large additional radial force between the cylinder piston and the cylinder wall, and between the oil cylinder piston / cylinder piston and the sealing assembly. This avoids unilateral wear of the piston, cylinder liner, and critical seals caused by this radial force, effectively preventing the failure of these critical vulnerable parts and improving the operational reliability, service life, and safety of the hydrogen-liquid driven pump.

[0039] In some embodiments, the hydraulic cylinder 1 further includes a hydraulic cylinder piston head 12, which is sealed within the oil chamber of the hydraulic cylinder 1, dividing the hydraulic cylinder into a first oil chamber and a second oil chamber. The first oil chamber is located near the first isolation cylinder 2, and the second oil chamber is located near the second isolation cylinder 3. The hydraulic cylinder piston head 12 is located at the middle of the hydraulic cylinder piston rod 11, which is fixedly connected. The first isolation cylinder 2 and the second isolation cylinder 3 are symmetrically distributed around the center of the hydraulic cylinder 1. The first end cylinder 4 and the second end cylinder 5 are symmetrically distributed around the center of the hydraulic cylinder 1. The first cylinder piston rod 41 and the second cylinder piston rod 51 are symmetrically distributed around the center of the hydraulic cylinder piston head 12.

[0040] In some embodiments, the connection portion between the second cylinder piston rod 51 and the second end of the oil cylinder piston rod 11 and the connection portion between the first cylinder piston rod 41 and the first end of the oil cylinder piston rod 11 have the same structure.

[0041] Specifically, the second cylinder piston rod 51 has the same external structure as the first cylinder piston rod 41, that is, the second cylinder piston rod 51 has a second protrusion 52 that mates with the second end of the hydraulic cylinder piston rod 11, and the second protrusion extends axially. The second end of the hydraulic cylinder piston rod 11 has a second groove 112 that opens axially. The second protrusion 52 and the second groove 112 are interlocked and used to limit the relative rotation between the hydraulic cylinder piston rod 11 and the second cylinder piston rod 51. Further, the second connecting assembly 7 includes a second pin, a second collar, and a second limiting member. It should be noted that the installation method of the second connecting assembly 7 is the same as that of the first connecting assembly 6, which can be referred to in the above description of the connection of the first connecting assembly 6 at the first end of the first cylinder piston rod 41 and the hydraulic cylinder piston rod 11, and will not be repeated here.

[0042] A second aspect of this application provides a hydrogen compressor, including a gas delivery pipe and a hydrogen-liquid driven pump as described above. The gas delivery pipe is disposed outside the hydrogen-liquid driven pump and is used to connect a first end cylinder 4 and a second end cylinder 5.

[0043] It should be noted that the diameters of the first end cylinder 4 and the second end cylinder 5 can be equal or unequal. Hydrogen-liquid driven pumps can operate in single-acting and double-acting modes, and their compression technologies can be single-stage or multi-stage. The structure of a hydrogen-liquid driven pump can be categorized into single-acting single-stage compression design, single-acting multi-stage compression design, double-acting single-stage compression design, and double-acting multi-stage compression design. Among these, the double-acting multi-stage compression pump structure is more complex, operates under harsh conditions, and requires high coaxiality. This embodiment uses a double-acting multi-stage compression design as an example. While the above forms may differ slightly depending on the design, the overall structural differences are not significant. Therefore, the floating piston rod structure in the hydrogen-liquid driven pump of this embodiment can be used in all of the above structural designs.

[0044] like Figure 6 As shown, the first end cylinder 4 also includes a first cylinder piston head, which is sealed inside the first end cylinder 4. The first end cylinder 4 has a first air chamber, and the first cylinder piston head divides the first cylinder into chamber A and chamber B. The first end cylinder 4 has a first air inlet, a second air inlet, a first exhaust port, and a second exhaust port. The second end cylinder 5 also includes a second cylinder piston head, which is sealed inside the second end cylinder. The second end cylinder 5 has a second air chamber, and the second cylinder piston head divides the second air chamber into chamber C and chamber D. The second end cylinder 5 has a third air inlet, a fourth air inlet, a third exhaust port, and a fourth exhaust port. The first exhaust port and the third air inlet are connected via a gas delivery pipe, and the second exhaust port and the fourth air inlet are connected via a gas delivery pipe. Both the first and second air inlets are connected to external equipment to allow hydrogen to enter the first air chamber, and both the third and fourth exhaust ports are connected to external equipment to output compressed hydrogen.

[0045] The hydrogen-hydraulic pump compresses hydrogen by driving a piston to reciprocate left and right using hydraulic oil. Its specific working principle is as follows: 1) Stroke 1: Hydraulic oil enters the second oil chamber of cylinder 1, driving the cylinder piston head 12 to move to the left, which in turn drives the cylinder piston rod 11, the first cylinder piston rod 41, and the second cylinder piston rod 51 to move to the left. The first cylinder piston head and the second cylinder piston head move to the left synchronously. At the same time, hydrogen gas enters chambers A and D through the first and second air inlets, and is compressed by the leftward movement of the first and second cylinder piston heads. The compressed hydrogen gas is discharged through the third and fourth exhaust ports. During the process, if... Figure 4 and Figure 5 As shown, there is a horizontal floating gap of 0.1-2 mm between the first cylinder piston rod 41 and the first pin 61 and the first collar 62, and a vertical floating gap of 0.1-2 mm between the first cylinder piston rod 41 and the first end of the oil cylinder piston rod 11. This allows the first cylinder piston rod 41 to float radially, compensating for the eccentricity between the first cylinder piston rod 41 and the oil cylinder piston rod 11. This ensures that the piston rod sealing assembly on the end cover of the first isolation cylinder 2 is subjected to uniform radial force, reducing friction loss. Simultaneously, there is a horizontal floating gap of 0.1-2 mm between the second cylinder piston rod 51 and the second pin and the second collar, and a vertical floating gap of 0.1-2 mm between the second cylinder piston rod 51 and the second end of the oil cylinder piston rod 11. This ensures that the second cylinder piston rod 51 is subjected to uniform radial force, compensating for the eccentricity between the second cylinder piston rod 51 and the oil cylinder piston rod 11. This ensures that the piston rod sealing assembly on the end cover of the second isolation cylinder 3 is subjected to uniform radial force, reducing friction loss. In addition, the connection between the first pin 61 and the first cylinder piston rod 41 and the oil cylinder piston rod 11 needs to be coated with grease or lubricating oil to prevent the first cylinder piston rod 41 and the oil cylinder piston rod 11 from colliding or rubbing hard against the first pin 61 during the reciprocating motion, which would cause wear and reduced strength at the connection between the first cylinder piston rod 41 and the oil cylinder piston rod 11, and also reduce noise; similarly, the connection between the second pin and the second cylinder piston rod 51 and the oil cylinder piston rod 11 also needs to be coated with grease or lubricating oil.

[0046] Stroke 2: After the cylinder piston head 12 reaches the left dead center, hydraulic oil enters the first oil chamber, driving the cylinder piston head 12 to move to the right, which in turn drives the cylinder piston rod 11, the first cylinder piston rod 41, and the second cylinder piston rod 51 to move to the right. At the same time, hydrogen gas enters chambers B and C through the first and second air inlets, and is compressed by the rightward movement of the first and second cylinder piston heads. The compressed hydrogen gas is discharged through the third and fourth exhaust ports. At this time, the first cylinder piston rod 41 and the second cylinder piston rod 51 are simultaneously in a radially free floating state, compensating for the eccentricity of the piston and piston rod relative to the cylinder and end cover, thereby reducing the wear of the cylinder piston and cylinder piston rod sealing assembly and extending its service life.

[0047] The above two strokes constitute one cycle, and the hydrogen-liquid pump continuously cycles back and forth to achieve continuous compression of hydrogen.

[0048] The first pin 61 connects the first cylinder piston rod 41 and the oil cylinder piston rod 11. The cross-sectional area S of the pin needs to be checked for strength. When the oil cylinder piston rod 11 pulls the first cylinder piston rod 41, the first pin 61 will be subjected to shear force. The maximum tensile force Fs on the oil cylinder piston rod 11 is calculated based on the maximum working pressure of the hydraulic oil and the cross-sectional area of ​​the oil cylinder piston head 12. The shear stress on the pin cross-section is τ = (Fs / 2) / A. The shear stress cannot be greater than the required shear stress, i.e., τ ≤ [τ], [τ] = 0.8σ / n, where σ is the tensile strength of the pin and n is the safety factor, which is taken as 2. Therefore, the design cross-sectional area A of the first pin 61 is ≥ Fs / (0.8σ).

[0049] A third aspect of this application provides a hydrogen refueling skid-mounted station, including the hydrogen compressor described above. The hydrogen refueling skid-mounted station is a highly integrated, modular, small-scale hydrogen refueling station that integrates core functions such as hydrogen compression, storage, cooling, and refueling into one or more skid-mounted modules. The core function of the hydrogen refueling skid-mounted station is to convert low-pressure hydrogen into high-pressure hydrogen and refuel it into a vehicle; this pressurization process is entirely completed by the hydrogen compressor. The hydrogen compressor is a key component within the hydrogen refueling skid-mounted station; it is integrated into the compression module or process module and works in conjunction with the hydrogen storage tank, control system, etc. The displacement (gas production capacity) and maximum outlet pressure of the hydrogen compressor directly determine the refueling speed of the entire skid-mounted station and the time required to fully refuel a vehicle.

[0050] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0051] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0052] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0053] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A hydrogen liquid-displacement pump characterized by, The hydrogen liquid drive pump comprises: a cylinder (1) comprising a cylinder piston rod (11); a first isolation cylinder (2) and a second isolation cylinder (3) respectively arranged at two ends of the cylinder (1); a first end cylinder (4) and a second end cylinder (5) respectively located at two ends of the hydrogen liquid drive pump; wherein a first cylinder piston rod (41) of the first end cylinder (4) is movably connected with a first end of the cylinder piston rod (11) and located in the first isolation cylinder (2), and a second cylinder piston rod (51) of the second end cylinder (5) is movably connected with a second end of the cylinder piston rod (11) and located in the second isolation cylinder (3).

2. The hydrogen liquid-displacement pump according to claim 1, characterized by, One end of the first cylinder piston rod (41) is provided with a first protrusion (42) extending in an axial direction, and a first groove (111) with an axial opening is formed in the first end of the cylinder piston rod (11), the first protrusion (42) is inserted and matched with the first groove (111) and used for limiting the relative rotation between the cylinder piston rod (11) and the first cylinder piston rod (41).

3. The hydrogen liquid-displacement pump of claim 2, wherein, The first protrusion (42) and the first groove (111) form a clearance fit.

4. The hydrogen liquid-displacement pump of claim 2, wherein, A radial pin hole passing through the alignment is formed between the first protrusion (42) and the first end of the cylinder piston rod (11), a first pin shaft (61) is inserted into the radial pin hole, and a radial gap is formed between the first pin shaft (61) and the hole wall of the radial pin hole, so that the cylinder piston rod (11) and the first cylinder piston rod (41) form a radial floating connection.

5. The hydrogen liquid-displacement pump of claim 4, wherein, The hydrogen liquid drive pump further comprises a first collar (62), the first collar (62) is sleeved on the connecting part between the first cylinder piston rod (41) and the first end of the cylinder piston rod (11), and both ends of the first pin shaft (61) abut against the inner wall of the first collar (62).

6. The hydrogen liquid-displacement pump of claim 5, wherein, A clamping limiting ring (63) is arranged at the axial end of the first collar (62).

7. The hydrogen liquid displacement pump of claim 5, wherein, The connecting part between the first cylinder piston rod (41) and the first end of the cylinder piston rod (11) is located in the first isolation cylinder (2), and the hydrogen liquid drive pump further comprises a position switch for monitoring the position of the connecting part, and the position switch is arranged between the outer side wall of the first collar (62) and the first isolation cylinder (2).

8. The hydrogen liquid displacement pump of any one of claims 1-7, wherein, In the first end cylinder (4) and the second end cylinder (5), the first cylinder piston rod (41) is movably connected with the first cylinder piston of the first end cylinder (4), and the second cylinder piston rod (51) is movably connected with the second cylinder piston of the second end cylinder (5).

9. A hydrogen compressor characterized by, The hydrogen compressor comprises a gas conveying pipe and the hydrogen liquid drive pump according to any one of claims 1-8, and the gas conveying pipe is arranged outside the hydrogen liquid drive pump and connected with the first end cylinder (4) and the second end cylinder (5).

10. A hydrogenation skid station characterized in that, The hydrogen compressor comprises the hydrogen compressor according to claim 9.

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