Fluid pressure energy recovery device and fluid switcher thereof

Abstract

The invention belongs to the technical field of pressure exchange, and discloses a fluid pressure energy recovery device and a fluid switcher thereof, and the fluid switcher comprises a first low-pressure barrel, a first connecting barrel, a high-pressure barrel, a second connecting barrel and a second low-pressure barrel; a piston assembly is arranged in a through cavity formed by the components and comprises a driving rod, a first piston, a piston rod and a second piston. The fluid switcher is connected with the first spiral pressure exchange cavity and the second spiral pressure exchange cavity through the piston traps, the first spiral pressure exchange cavity and the second spiral pressure exchange cavity are connected with the check valve set through the piston traps respectively, spherical isolation pistons are arranged in the first spiral pressure exchange cavity and the second spiral pressure exchange cavity respectively, and the spherical isolation pistons can be trapped by the piston traps. The fluid pressure energy recovery device has the advantages of being long in service life, small in occupied area, low in energy consumption and low in liquid mixing rate. The fluid switcher has the advantages of being high in structural component integration degree, low in switcher body energy loss, convenient to assemble and maintain and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of pressure energy recovery, and in particular, relates to a fluid pressure energy recovery device and a fluid switcher thereof. Background Art

[0002] As one of the key technologies to solve the global shortage of fresh water resources, reverse osmosis desalination has been widely used in many countries and regions. The reverse osmosis desalination process is a pressure-driven membrane separation process. The pre-treated seawater is pressurized to 5.5-8.0MPa by a high-pressure pump and enters the reverse osmosis membrane assembly. 40% of the seawater inflow passes through the membrane assembly to become product fresh water, and most of the seawater flow is intercepted by the membrane assembly to become concentrated brine. This part of concentrated brine has a similar pressure level to the seawater entering the membrane. If it is discharged directly, it will cause huge energy waste. Therefore, using a fluid pressure energy recovery device to recycle the pressure energy contained in the concentrated brine can greatly reduce the system energy consumption of the reverse osmosis desalination process and achieve energy-saving and efficient operation of the process.

[0003] Processes such as chemical reactions, separation of systems, and fluid transportation usually include two important processes: pressurization of low-pressure fluids and pressure relief of high-pressure fluids. Pressurization of low-pressure fluids requires the use of fluid equipment to do work on the fluid and input energy into the fluid; pressure relief of high-pressure fluids involves the process of high-pressure fluids releasing energy into the environment. If the high-pressure fluid is directly depressurized, the energy is directly dissipated in the environment, which will cause huge energy waste. With the help of a fluid pressure energy recovery device, the pressure relief of high-pressure fluids is combined with the pressurization of low-pressure fluids to recycle and utilize the pressure energy, thereby achieving energy saving and consumption reduction in the process. Summary of the invention

[0004] The present invention provides a fluid pressure energy recovery device and a fluid switcher thereof. The fluid pressure energy recovery device has the advantages of long service life, small footprint, low energy consumption and low liquid mixing rate. The fluid switcher has the advantages of high integration of structural components, low energy loss of the switcher body and easy assembly and maintenance.

[0005] In order to achieve the above-mentioned object of the invention, the present invention is implemented by the following technical solutions:

[0006] According to one aspect of the present invention, there is provided a fluid switch, comprising a first low-pressure cylinder, a first connecting cylinder, a high-pressure cylinder, a second connecting cylinder, and a second low-pressure cylinder coaxially arranged in sequence from top to bottom;

[0007] The first low-pressure cylinder is provided with a first axial through cavity, the inner diameter of the bottom end of the first axial through cavity gradually increases toward the port direction to form a first sealing surface; the top end of the first low-pressure cylinder is provided with a first upper end flange; the lower part of the first low-pressure cylinder is provided with a first lower end flange above the first sealing surface; the first low-pressure cylinder is connected to a first low-pressure fluid interface, the first low-pressure fluid interface is located between the first upper end flange and the first lower end flange, and is connected to the first axial through cavity;

[0008] The first connecting cylinder is provided with a first annular fluid confluence cavity, the inner diameter of which is larger than the outer diameters of the first low-pressure cylinder and the high-pressure cylinder; the top and bottom ends of the first connecting cylinder are respectively provided with a first sealed connecting channel and a second sealed connecting channel, the inner diameters of the first sealed connecting channel and the second sealed connecting channel match the outer diameters of the first low-pressure cylinder and the high-pressure cylinder; the first connecting cylinder is connected with a first fluid flow interface, and the first fluid flow interface is connected with the first annular fluid confluence cavity;

[0009] The high-pressure cylinder is provided with a second axial through cavity, and the inner diameters of the top and bottom ends of the second axial through cavity gradually increase toward the port direction, forming the second sealing surface and the third sealing surface; the upper and lower parts of the high-pressure cylinder are respectively provided with a second upper end flange and a second lower end flange, and the second upper end flange and the second lower end flange are located between the second sealing surface and the third sealing surface; sealing grooves are respectively provided on the outer rotating surface of the high-pressure cylinder between the second sealing surface and the second upper end flange, and between the second lower end flange and the third sealing surface; the high-pressure cylinder is connected with a high-pressure fluid interface, and the high-pressure fluid interface is located between the second upper end flange and the second lower end flange, and is communicated with the second axial through cavity;

[0010] The second connecting cylinder is provided with a second annular fluid confluence chamber, the inner diameter of which is larger than the outer diameters of the high-pressure cylinder and the second low-pressure cylinder; the top and bottom ends of the second connecting cylinder are respectively provided with a third sealed connection channel and a fourth sealed connection channel, the inner diameters of the third sealed connection channel and the fourth sealed connection channel match the outer diameters of the high-pressure cylinder and the second low-pressure cylinder; the second low-pressure cylinder is connected with a second low-pressure fluid interface, and the second fluid flow interface is connected with the second annular fluid confluence chamber;

[0011] The second low-pressure cylinder is provided with a third axial through cavity, the inner diameter of the top end of the third axial through cavity gradually increases toward the port direction to form a fourth sealing surface; the bottom end of the third axial through cavity is provided with a third lower end flange; the upper part of the second low-pressure cylinder is provided with a third upper end flange below the fourth sealing surface; the second connecting cylinder is connected with a second fluid flow interface, the second low-pressure fluid interface is located between the third upper end flange and the fourth lower end flange, and is connected with the third axial through cavity;

[0012] The first low-pressure cylinder is sealed and connected to a driving end cover via a first upper end flange, and the second low-pressure cylinder is sealed and connected to a sealing end cover via a third lower end flange;

[0013] There is a distance between the first low-pressure cylinder and the high-pressure cylinder, the first connecting cylinder is sleeved on the outside of the first low-pressure cylinder and the high-pressure cylinder, and is sealed and connected to the first lower end flange through the upper end face of the first connecting cylinder, and is sealed and connected to the second upper end flange through the lower end face of the first connecting cylinder, so that the first connecting cylinder seals and connects the first low-pressure cylinder and the high-pressure cylinder;

[0014] There is a distance between the high-pressure cylinder and the second low-pressure cylinder, the second connecting cylinder is sleeved on the outside of the high-pressure cylinder and the second low-pressure cylinder, and is sealed and connected to the second lower end flange through the upper end face of the second connecting cylinder, and is sealed and connected to the third upper end flange through the lower end face of the second connecting cylinder, so that the second connecting cylinder seals and connects the high-pressure cylinder and the second low-pressure cylinder;

[0015] A piston assembly is arranged in the through cavity formed by the first low-pressure cylinder, the high-pressure cylinder, the second low-pressure cylinder, the first low-pressure cylinder, and the second low-pressure cylinder, and the piston assembly reciprocates under the drive of the driving mechanism;

[0016] The piston assembly comprises a driving rod, a first piston, a piston rod and a second piston which are coaxially connected in sequence from top to bottom;

[0017] The upper portion of the driving rod passes through the through hole of the driving end cover and is connected to the driving mechanism; a dynamic seal is formed between the through hole of the driving end cover and the driving rod;

[0018] The outer rotating surface of the first piston is provided with a plurality of first seal installation grooves, and the plurality of first seal installation grooves are installed with sealing rings to form a multi-stage dynamic seal between the first piston and the first low-pressure cylinder and the high-pressure cylinder; the outer rotating surface of the second piston is provided with a plurality of second seal installation grooves, and the plurality of second seal installation grooves are installed with sealing rings to form a multi-stage dynamic seal between the second piston and the high-pressure cylinder and the second low-pressure cylinder.

[0019] Furthermore, the outer diameters and inner diameters of the first low-pressure cylinder, the high-pressure cylinder, and the second low-pressure cylinder are all the same.

[0020] Furthermore, the upper end surface and the lower end surface of the first connecting cylinder are respectively provided with blind bolt holes, and the upper end surface and the lower end surface of the second connecting cylinder are respectively provided with blind bolt holes.

[0021] Furthermore, a sealing groove is provided on the outer rotating surface of the first low-pressure cylinder between the first lower end flange and the first sealing surface, and a sealing groove is provided on the outer rotating surface of the second low-pressure cylinder between the fourth sealing surface and the third upper end flange.

[0022] Furthermore, the outer rotating surface of the first piston is provided with a plurality of first throttling grooves, and the plurality of first throttling grooves are arranged between the two end surfaces of the first piston and the first sealing installation groove; the outer rotating surface of the second piston is provided with a plurality of first throttling grooves, and the plurality of second throttling grooves are arranged between the two end surfaces of the second piston and the second sealing installation groove.

[0023] Furthermore, the first piston is threadedly connected to the driving rod and the piston rod respectively, and the second piston is threadedly connected to the piston rod.

[0024] According to another aspect of the present invention, there is provided a fluid pressure energy recovery device, comprising a fluid switcher as described in any one of claims 1 to 6; the first fluid flow interface of the fluid switcher is connected to the first end interface of the first spiral pressure exchange chamber through a piston catcher, and the second fluid flow interface of the fluid switcher is connected to the first end interface of the second spiral pressure exchange chamber through a piston catcher; the second end interface of the first spiral pressure exchange chamber is connected to the first check valve group through the piston catcher, and the second end interface of the second spiral pressure exchange chamber is connected to the second check valve group through the piston catcher;

[0025] The first spiral pressure exchange chamber and the second spiral pressure exchange chamber are both configured as spiral pressure channels;

[0026] A spherical isolation piston is arranged inside the first spiral pressure exchange chamber and the second spiral pressure exchange chamber. The spherical isolation piston is used to isolate two pressure exchange fluids and moves with the flow of the fluids. When the spherical isolation piston moves to the ends of the first spiral pressure exchange chamber and the second spiral pressure exchange chamber, it can be captured by the piston catcher. The piston catcher is used to limit the stroke of the spherical isolation piston without blocking the flow channel.

[0027] Furthermore, the spiral pressure channel adopts a circular spiral or a rectangular spiral.

[0028] Further, the piston trap is composed of a trap outer shell and a trap inner part, and the trap outer part and the trap inner part are sealed and connected;

[0029] The trap outer part comprises a shell, the shell is provided with a first fluid connector, the first fluid connector is used to connect with the first fluid flow interface or the second fluid flow interface of the fluid switch; the shell is provided with a flow cavity, the flow cavity is open on the top surface of the shell, and is connected with the first fluid connector;

[0030] The trap internals include a trap cage, the top of the trap cage is open, and the circumferential flow holes and the axial flow holes are respectively arranged on the circumference and bottom surfaces; the top opening of the trap cage is coaxially connected to the second fluid connector through a connecting flange; the second fluid connector is used to connect to the first end interfaces of the first spiral pressure exchange chamber and the second spiral pressure exchange chamber;

[0031] The capture cage of the collector inner part is located in the flow cavity of the collector outer part, and the flow cavity is coaxially arranged with the capture cage to form an annular flow cavity; the collector inner part is sealed and connected to the top surface of the shell through a connecting flange.

[0032] Furthermore, the first check valve group and the second check valve group both include a three-way pipe, the three-way pipe having a first interface, a second interface and a third interface; the first interface is used to connect the piston catcher; the second interface is connected to a first straight pipe through a first check valve, and the first straight pipe is used for fluid outflow; the third interface is connected to a second straight pipe through a second check valve, and the second straight pipe is used for fluid inflow.

[0033] The beneficial effects of the present invention are:

[0034] (1) The fluid switcher of the present invention and the fluid pressure energy recovery device based on the fluid switcher adopt a single-shell structure design, in which the pressure-bearing component and the sealing component are combined into one, and the overall structural components are simplified; and a straight-open flow channel structure is adopted, the flow channel stroke is shorter, and the energy consumption of the switcher body is lower; in addition, the fluid switcher adopts a symmetrical structural design, the types of parts are reduced, and the difficulty of manufacturing and assembly is reduced.

[0035] (ii) The fluid switcher of the present invention and the fluid pressure energy recovery device based on the fluid switcher have a valve core that adopts a pressure self-balancing design, which reduces driving energy consumption while having good static stability; the valve core sealing component adopts a gradual opening and closing mode to avoid wear and damage to the seal, while eliminating cavitation damage between high and low pressure fluids.

[0036] (III) The fluid pressure energy recovery device of the present invention has a spiral pressure chamber which can make the pressure exchange chamber more compact, reduce the floor space, increase the flow path length, and stabilize the fluid flow state.

[0037] (IV) The fluid pressure energy recovery device of the present invention adopts a spherical piston to suppress the mixing of the pressure exchange fluid, and at the same time can move freely and smoothly with the pressure exchange fluid inside the spiral pressure chamber; its piston catcher can efficiently capture the piston and limit the piston movement space within the pressure exchange chamber, and at the same time the piston catcher can ensure the fluidity of the pressure exchange chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the overall structure of the fluid pressure energy recovery device provided by the embodiment of the present invention;

[0039] Figure 2 is a cross-sectional schematic diagram of a fluid switcher in a forward working position provided by an embodiment of the present invention;

[0040] Figure 3 is a cross-sectional schematic diagram of a fluid switcher in a retreated working position provided by an embodiment of the present invention;

[0041] Figure 4 It is a cross-sectional schematic diagram of a first low-pressure cylinder in a fluid switcher provided by an embodiment of the present invention;

[0042] Figure 5 is a cross-sectional schematic diagram of a first connecting cylinder in a fluid switcher provided by an embodiment of the present invention;

[0043] Figure 6 It is a cross-sectional schematic diagram of a high-pressure cylinder in a fluid switcher provided by an embodiment of the present invention;

[0044] Figure 7 is a cross-sectional schematic diagram of a second connecting cylinder in a fluid switcher provided by an embodiment of the present invention;

[0045] Figure 8 is a cross-sectional schematic diagram of a second low-pressure cylinder in a fluid switcher provided by an embodiment of the present invention;

[0046] Fig. 9 It is a structural schematic diagram of a piston assembly provided by an embodiment of the present invention;

[0047] Fig.10 is a cross-sectional schematic diagram of a first piston provided by an embodiment of the present invention;

[0048] Fig.11 is a cross-sectional schematic diagram of a second piston provided by an embodiment of the present invention;

[0049] Fig.12 It is a cross-sectional schematic diagram of the piston in the piston trap provided by the embodiment of the present invention when the piston is not trapped;

[0050] Fig.13 It is a cross-sectional schematic diagram of the piston being captured in the piston catcher provided by the embodiment of the present invention;

[0051] Fig.14 It is a structural schematic diagram of the piston catcher housing provided by the embodiment of the present invention;

[0052] Fig.15 It is a schematic diagram of the structure of the piston catcher internal parts provided by the embodiment of the present invention;

[0053] Fig.16 It is a cross-sectional schematic diagram of the check valve group provided by the embodiment of the present invention.

[0054] In the above figure: 1-fluid switch; 101-first low-pressure cylinder, 1011-first axial through cavity, 1012-first sealing surface, 1013-first upper end flange, 1014-first lower end flange; 102-first low-pressure fluid interface; 103-first piston, 1031-first throttling groove, 1032-first sealing member installation groove, 1033-first connecting hole, 1034-second connecting hole; 104-high-pressure cylinder; 1041-second axial through cavity, 1042-second sealing surface, 1043-third sealing surface, 1044-second upper end flange, 1045-second lower end flange; 105-high-pressure fluid interface; 106-second piston, 1061-second throttling groove, 1062-second sealing member installation groove Groove, 1063-third connecting hole; 107-second low-pressure cylinder; 1071-third axial through cavity, 1072-fourth sealing surface, 1073-third upper end flange, 1074-third lower end flange; 108-second low-pressure fluid interface, 109-sealed end cover, 110-second fluid flow interface, 111-second connecting cylinder, 1111-second annular fluid confluence cavity, 1112-third sealed connecting channel, 1113-fourth sealed connecting channel; 112-piston rod; 113-first fluid flow interface; 114-first connecting cylinder, 1141-first annular fluid confluence cavity, 1142-first sealed connecting channel, 1143-second sealed connecting channel; 115-driving rod, 116-driving end cover;

[0055] 2-first spiral pressure exchange chamber;

[0056] 3-second spiral pressure exchange chamber;

[0057] 4-first check valve group, 41-first three-way pipe, 42-first check valve, 43-first straight pipe, 44-second check valve, 45-second straight pipe;

[0058] 5-Second check valve group;

[0059] 6-piston catcher; 61-catcher housing, 611-shell, 612-first fluid connector, 613-circulation chamber; 62-catcher internals, 621-catch cage, 622-fluid connector, 623-connecting flange, 624-circumferential flow hole, 625-axial flow hole; 7-spherical isolation piston. DETAILED DESCRIPTION

[0060] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0061] like Figure 1As shown, the fluid pressure energy recovery device provided by the present invention mainly includes a fluid switcher 1, a first spiral pressure exchange chamber 2, a second spiral pressure exchange chamber 3, a first check valve group 4, a second check valve group 5, four piston catchers 6, and two spherical isolation pistons 7.

[0062] The fluid switch 1 is used to connect the driving mechanism for reciprocating switching to achieve switching of the energy recovery process.

[0063] Among them, the two ends of the first spiral pressure exchange chamber 2 are connected to the fluid switcher 1 and the first check valve group 5 through the piston catcher 6; the two ends of the second spiral pressure exchange chamber 3 are connected to the fluid switcher 1 and the second check valve group 5 through the piston catcher 6.

[0064] The first check valve group 4 and the second check valve group 5 use multiple check valves to work in coordination to achieve the entry of the energy receiving fluid and the discharge of the energy supplying fluid.

[0065] like Figure 2 , Figure 3 As shown, the fluid switch 1 includes a first low-pressure cylinder 101, a high-pressure cylinder 104, and a second low-pressure cylinder 107, which are arranged in sequence from top to bottom. The first low-pressure cylinder 101, the high-pressure cylinder 104, and the second low-pressure cylinder 107 have the same outer diameter and the same inner diameter. There is a spacing between the first low-pressure cylinder 101 and the high-pressure cylinder 104 and they are connected by a first connecting cylinder 114, and there is a spacing between the high-pressure cylinder 104 and the second low-pressure cylinder 107 and they are connected by a second connecting cylinder 111.

[0066] The central axes of the first low-pressure cylinder 101 , the high-pressure cylinder 104 , the second low-pressure cylinder 107 , the first connecting cylinder 114 , and the second connecting cylinder 111 are all the same, and a piston assembly is disposed in the through cavity composed of the five components.

[0067] The top end of the first low-pressure cylinder 101 is connected to the driving end cover 116 by flange, and the bottom end of the second low-pressure cylinder 107 is connected to the sealing end cover 109 by flange. The first low-pressure cylinder 101 is connected to the first low-pressure fluid interface 102, the high-pressure cylinder 104 is connected to the high-pressure fluid interface 105, and the second low-pressure cylinder 107 is connected to the second low-pressure fluid interface 108. The first connecting cylinder 114 is connected to the first fluid circulation interface 113, and the second connecting cylinder 111 is connected to the second fluid circulation interface 110.

[0068] The fluid switcher 1 adopts a single-shell structure, which greatly simplifies the flow channel structure in the switcher and reduces the resistance loss during the fluid flow process.

[0069] Combination Figure 4As shown, the first low-pressure cylinder 101 is a cylindrical structure, including a first axial through cavity 1011, and the inner diameter of the bottom end of the first axial through cavity 1011 gradually increases toward the port direction, forming a first sealing surface 1012 with a gradual inclination. A first upper end flange 1013 is provided at the top of the first axial through cavity 1011, and the first upper end flange 1013 is used to be sealed and connected with the drive end cover 116. A first lower end flange 1014 is provided at the lower part of the first low-pressure cylinder 101, above the first sealing surface 1012, and the first lower end flange 1014 is used to connect the first connecting cylinder 114. A sealing groove is provided on the outer rotating surface of the first low-pressure cylinder 101 between the first lower end flange 1014 and the first sealing surface 1012. The first low-pressure fluid interface 102 is located between the first upper end flange 1013 and the first lower end flange 1014, is arranged along the radial direction of the first low-pressure cylinder 101 and is connected with the first axial through cavity 1011.

[0070] Combination Figure 5 As shown, the first connecting cylinder 114 is a cylindrical structure, and a first annular fluid confluence chamber 1141 is arranged inside the first connecting cylinder 114. The inner diameter of the first annular fluid confluence chamber 1141 is larger than the outer diameter of the first low-pressure cylinder 101 and the high-pressure cylinder 104, so as to realize the annular amplification of the circulation chamber and conduct fluid confluence. The top and bottom ends of the first connecting cylinder 114 are respectively provided with a first sealed connection channel 1142 and a second sealed connection channel 1143, and the first sealed connection channel 1142 and the second sealed connection channel 1143 are both axially connected with the first annular fluid confluence chamber 1141. The inner diameters of the first sealed connection channel 1142 and the second sealed connection channel 1143 match the outer diameters of the first low-pressure cylinder 101 and the high-pressure cylinder 104 to realize radial positioning and the matching requirements of the seal. The upper end face and the lower end face of the first connecting cylinder 114 are respectively provided with bolt blind holes, and the bolt blind holes are respectively uniformly distributed in the upper end face and the lower end face in the annular direction. The first fluid flow interface 113 is disposed along the radial direction of the first connecting cylinder 114 and is communicated with the first annular fluid confluence cavity 1141 .

[0071] Combination Figure 6As shown, the high-pressure cylinder 104 is a cylindrical structure, including a second axial through cavity 1041, and the inner diameters of the top and bottom ends of the second axial through cavity 1011 gradually increase toward the port direction, forming a second sealing surface 1042 and a third sealing surface 1043 with a gradual inclination. The upper and lower parts of the high-pressure cylinder 104 are respectively provided with a second upper end flange 1044 and a second lower end flange 1045, and the second upper end flange 1044 and the second lower end flange 1045 are located between the second sealing surface 1042 and the third sealing surface 1043, and are respectively used to connect the first connecting cylinder 114 and the second connecting cylinder 111. Sealing grooves are respectively provided on the outer rotating surface of the high-pressure cylinder 104 between the second sealing surface 1042 and the second upper end flange 1044, and between the second lower end flange 1045 and the third sealing surface 1043. The high-pressure fluid interface 105 is located between the second upper end flange 1044 and the second lower end flange 1045 , is disposed along the radial direction of the high-pressure cylinder 104 , and is communicated with the second axial through cavity 1041 .

[0072] Combination Figure 7 As shown, the second connecting cylinder 111 is a cylindrical structure, and a second annular fluid confluence chamber 1111 is arranged inside the second connecting cylinder 111. The inner diameter of the second annular fluid confluence chamber 1111 is larger than the outer diameter of the high-pressure cylinder 104 and the second low-pressure cylinder 107, so as to realize the annular amplification of the circulation chamber and conduct fluid confluence. The top and bottom ends of the second connecting cylinder 111 are respectively provided with a third sealed connection channel 1112 and a fourth sealed connection channel 1113, and the third sealed connection channel 1112 and the fourth sealed connection channel 1113 are axially connected with the second annular fluid confluence chamber 1111. The inner diameters of the third sealed connection channel 1112 and the fourth sealed connection channel 1113 match the outer diameters of the high-pressure cylinder 104 and the second low-pressure cylinder 107 to achieve the matching requirements of the seal. The upper end face and the lower end face of the second connecting cylinder 111 are respectively provided with bolt blind holes, and the bolt blind holes are respectively uniformly distributed in the upper end face and the lower end face in an annular direction. The second fluid flow interface 110 is disposed along the radial direction of the second connecting cylinder 111 and communicates with the second annular fluid confluence chamber 1111 .

[0073] Combination Figure 8As shown, the second low-pressure cylinder 107 is a cylindrical structure, including a third axial through cavity 1071, and the inner diameter of the top of the third axial through cavity 1071 gradually increases toward the port direction, forming a fourth sealing surface 1072 with a gradient inclination. A third lower end flange 1074 is provided at the bottom end of the third axial through cavity 1071, and the third lower end flange 1074 is used for sealing connection with the sealing end cover 109. A third upper end flange 1073 is provided at the upper part of the second low-pressure cylinder 107 below the fourth sealing surface 1072, and the third upper end flange 1073 is used for connecting the second connecting cylinder 111. A sealing groove is provided on the outer rotating surface of the second low-pressure cylinder 107 between the fourth sealing surface 1072 and the third upper end flange 1073. The second low-pressure fluid interface 108 is located between the third upper end flange 1073 and the fourth lower end flange 1074, and is connected to the third axial through cavity 1071.

[0074] The first connecting cylinder 114 is sleeved on the outer side of the lower part of the first low-pressure cylinder 101 and the outer side of the upper part of the high-pressure cylinder 104. The upper end face of the first connecting cylinder 114 is connected to the first lower end flange 1014 of the first low-pressure cylinder 101 and bolts are evenly distributed in the annular direction are installed, and the lower end face of the first connecting cylinder 114 is connected to the second upper end flange 1044 of the high-pressure cylinder 104 and bolts are evenly distributed in the annular direction are installed, so that the first connecting cylinder 114 connects the first low-pressure cylinder 101 and the high-pressure cylinder 104. At the same time, sealing rings are installed in the sealing grooves at the lower part of the first low-pressure cylinder 101 and the upper part of the high-pressure cylinder 104 to achieve static sealing between the first connecting cylinder 114 and the first low-pressure cylinder 101, and between the first connecting cylinder 114 and the high-pressure cylinder 104.

[0075] The second connecting cylinder 111 is sleeved on the outer side of the lower part of the high-pressure cylinder 104 and the outer side of the upper part of the second low-pressure cylinder 107, and the upper end face of the second connecting cylinder 111 is connected with the second lower end flange 1045 of the high-pressure cylinder 104 and bolts uniformly distributed in the circumferential direction are installed, and the lower end face of the second connecting cylinder 111 is connected with the third upper end flange 1073 of the second low-pressure cylinder 107 and bolts uniformly distributed in the circumferential direction are installed, so that the second connecting cylinder 111 connects the high-pressure cylinder 104 and the second low-pressure cylinder 107. At the same time, a sealing ring is installed in the sealing groove at the lower part of the high-pressure cylinder 104 and the upper part of the second low-pressure cylinder 107 to achieve static sealing between the second connecting cylinder 111 and the high-pressure cylinder 104, and between the second connecting cylinder 111 and the second low-pressure cylinder 107.

[0076] The above fluid switcher 1 adopts a gradual opening and closing structure to avoid mechanical impact damage and fluid cavitation damage to the seal and the matching surface, thereby increasing the operating life of the fluid switcher.

[0077] The piston assembly performs reciprocating motion inside the fluid switcher 1 under the drive of the driving mechanism.

[0078] like Fig. 9 As shown, the piston assembly includes a driving rod 115, a first piston 103, a piston rod 112, and a second piston 106. The first piston 103 and the second piston 106 are connected through the piston rod 112. The driving rod 115 is connected to the first piston 103, passes through the through hole of the driving end cover 116, and is connected to the external driving mechanism. A dynamic seal is formed between the through hole of the driving end cover 116 and the driving rod 115.

[0079] like Fig.10 As shown, the outer rotating surface of the first piston 103 is provided with a plurality of first seal installation grooves 1032, which are arranged in the middle section of the first piston 103 and are used to install sealing rings to form a dynamic seal between the first piston 103 and the first low-pressure cylinder 101 and the high-pressure cylinder 104. Further preferably, the outer rotating surface of the first piston 103 is also provided with a plurality of first throttling grooves 1031, which are arranged between the two end surfaces of the first piston 103 and the first seal installation grooves 1032, and are used to throttle and reduce the pressure of the high-pressure fluid, playing a role of preliminary interception and sealing. The top end of the first piston 103 is provided with a first connecting hole 1033 along its central axis, which is used to be threadedly connected to the lower end of the driving rod 115. The bottom end of the first piston 103 is provided with a first connecting hole 1034 along its central axis, which is used to be threadedly connected to the upper end of the piston rod 112.

[0080] like Fig.11 As shown, the outer rotating surface of the second piston 106 is provided with a plurality of second seal installation grooves 1062, which are arranged in the middle section of the second piston 106 for installing sealing rings to form a dynamic seal between the second piston 106 and the high-pressure cylinder 104 and the second low-pressure cylinder 107. Further preferably, the outer rotating surface of the second piston 106 is also provided with a plurality of second throttling grooves 1061, which are arranged between the two end surfaces of the second piston 106 and the second seal installation grooves 1062, for throttling and reducing the pressure of the high-pressure fluid, and playing a role of preliminary interception and sealing. The top of the second piston 106 is provided with a third connecting hole 1063 along its central axis for threaded connection with the lower end of the piston rod 112.

[0081] The fluid switch 1 adopts a straight-through flow channel structure to eliminate the flow energy loss caused by complex flow channels and pipeline bypass. At the same time, the double-piston valve core adopts a pressure self-balancing structure, which can balance the axial force of the valve core and reduce the energy consumption of working position switching. The synergistic effect of the two makes the device's own energy consumption low and improves the device's energy recovery efficiency. At the same time, the reduction in the number of parts and components contained in the fluid switch 1 and the simplification of the types of parts reduce the difficulty of manufacturing and assembly.

[0082] The first piston 103 and the second piston 106 adopt a multi-stage sealing structure, which not only avoids the cross-flow between high-pressure and low-pressure fluids during the dynamic switching process of the fluid switcher 1, but also ensures the high sealing performance of the fluid switcher 1 when it is maintained statically. In addition, the multi-stage sealing component adopts a gradual closing and gradual opening action process, which, on the one hand, reduces the wear rate of the seal and avoids damage to the seal during the switching process; on the other hand, the gradual closing and gradual opening process alleviates the sudden change of fluid pressure, suppresses equipment vibration and reduces local cavitation at the sealing surface, thereby increasing the operating life of the fluid switcher 1.

[0083] The first spiral pressure exchange chamber 2 and the second spiral pressure exchange chamber 3 are both configured as spiral pressure channels, and the spiral pressure channels can be circular spirals or rectangular spirals. Circular spirals or rectangular spirals refer to the projection of the pressure channels on a plane being circular or rectangular. The spiral pressure channels can provide a longer pressure exchange space at the same axial distance, reduce the floor space of the pressure exchange chamber, and make the device more compact.

[0084] A spherical isolation piston 7 is disposed inside the first spiral pressure exchange chamber 2 and the second spiral pressure exchange chamber 3. The spherical isolation piston 7 is used to isolate the two pressure exchange fluids and move freely with the flow of the fluids. Compared with the traditional cylindrical isolation piston, the spherical isolation piston 7 runs more smoothly, has lower movement resistance and is not easy to get stuck, and can better control the mixing rate of the fluid.

[0085] The piston catcher 6 is arranged at both ends of the first spiral pressure exchange chamber 2 and the second spiral pressure exchange chamber 3, that is, the first spiral pressure exchange chamber 2 and the second spiral pressure exchange chamber 3 are respectively equipped with two piston catchers 6, and when the spherical isolation piston 7 moves to the ends of the first spiral pressure exchange chamber 2 and the second spiral pressure exchange chamber 3, it is captured by the piston catcher 6. The piston catcher 6 can limit the stroke of the spherical isolation piston 7 without blocking the flow channel.

[0086] like Fig.12 and Fig.13 As shown, the piston catcher 6 is composed of a catcher outer shell 61 and a catcher inner part 62, and the catcher outer part 61 and the catcher inner part 62 are sealed and connected.

[0087] like Fig.14As shown, the trap outer part 61 includes a shell 611, and a first fluid connector 612 is provided on one side of the shell 611. The first fluid connector 612 is used to connect with the first fluid flow interface 113 or the second fluid flow interface 110 of the fluid switch 1. A cylindrical flow cavity 613 is provided inside the shell 611. The flow cavity 613 is open on the top surface of the shell 611 and is connected to the first fluid connector 612. The top surface of the shell 611 is provided with circumferentially uniformly distributed bolt blind holes for connecting with the trap inner part 62.

[0088] like Fig.15 As shown, the inner part 62 of the collector includes a capture cage 621, which is a cylindrical structure with an open top. The circumferential flow hole 624 and the axial flow hole 625 are respectively arranged on the circumference and bottom surface thereof for fluid inlet and outlet. The top opening of the capture cage 621 is connected to the second fluid connector 622 through a connecting flange 623. The capture cage 621 is coaxially connected with the second fluid connector 622. The capture cage 621, the second fluid connector 622 and the connecting flange 623 are usually integrally formed. The second fluid connector 622 is used to connect to the first end interface of the first spiral pressure exchange chamber 2 and the second spiral pressure exchange chamber 3. The outer rotating surface of the upper part of the capture cage 621 is provided with a static sealing groove for installing a sealing ring to form a seal between the inner part 62 of the collector and the outer part 61 of the collector.

[0089] The axial directions of the second fluid connector 622 of the collector inner part 62 and the first fluid connector 612 of the collector outer part 61 are perpendicular to each other.

[0090] The inner part 62 of the collector is placed through the top opening of the outer part 61 of the collector, so that the cage 621 is located in the flow cavity 613 of the outer part 61 of the collector, and the connecting flange 623 is connected to the top surface of the shell 611. The flow cavity 613 of the outer part 61 of the collector is coaxially arranged with the cage 621 of the inner part 62 of the collector, and an annular flow cavity is formed between the two, which can realize the convergence and distribution of the fluid. The outer part 61 of the collector and the inner part 62 of the collector are fixedly connected by installing bolts in the bolt blind holes of the connecting flange 623 and the top surface of the shell 611; at the same time, the sealing ring installed in the circumferential sealing groove of the inner part 62 of the collector realizes the static seal between the outer part 61 of the collector and the inner part 62 of the collector.

[0091] As a preferred embodiment, the shell 611 of the collector outer part 61 and the connecting flange 623 of the collector inner part 62 both have square cross-sections with rounded chamfers; the connecting bolts are respectively located at the four corners of the shell 611 and the connecting flange 623.

[0092] like Fig.16As shown, the first check valve assembly 4 includes a first three-way pipe 41, and the first three-way pipe 41 has a first interface, a second interface and a third interface. The first interface is used to connect the piston catcher 6; the second interface is connected to the first straight pipe 43 through the first check valve 42, and the first straight pipe 43 is used for fluid outflow; its third interface is connected to the second straight pipe 45 through the second check valve 44, and the second straight pipe 45 is used for fluid inflow.

[0093] Likewise, the structure of the second check valve group 5 is completely the same as that of the first check valve group 4, and will not be described in detail herein.

[0094] The first end interface of the first spiral pressure exchange chamber 2 is connected to the first fluid flow interface 113 of the fluid switch 1 through the piston catcher 6 , and the second end interface is connected to the first interface of the first check valve group 4 through the piston catcher 6 .

[0095] The first end interface of the second spiral pressure exchange chamber 3 is connected to the second fluid flow interface 110 of the fluid switch 1 through the piston catcher 6 , and the second end interface is connected to the first interface of the second check valve group 5 through the piston catcher 6 .

[0096] The fluid pressure energy recovery device provided by the present invention has the following working process:

[0097] According to the different positions of the first piston 103 and the second piston 106 in the fluid switcher 1, the fluid pressure energy recovery device has two typical working states: a forward working position state and a backward working position state. The two working states are alternately switched by the reciprocating movement of the piston.

[0098] Figure 2 The fluid switcher is shown in the forward working position. The high-pressure fluid enters the second axial through cavity 1041 of the high-pressure cylinder 104 through the high-pressure fluid interface 105, flows through the first annular fluid confluence cavity 1141 of the first connecting cylinder 114, and enters the first piston catcher 2 through the first fluid flow interface 113. In the piston catcher 2 on the side of the fluid switcher 1, the high-pressure fluid passes through the circumferential flow hole 624 and the axial flow hole 625 provided in the catcher inner part 62, and pushes the spherical piston 20 into the first spiral pressure exchange chamber 2. In the first spiral pressure exchange chamber 2, the high-pressure fluid pushes the spherical piston 20 to pressurize the low-pressure fluid, and the spherical piston 20 moves toward the first check valve group 4 until it is captured by the piston catcher 4 on the side of the first check valve group 4. The pressurized fluid enters the first check valve group 4, passes through the first three-way pipe 41 and the first check valve 42, and flows out from the first straight pipe 43.

[0099] At the same time, the low-pressure fluid enters the piston catcher 2 on the side of the second check valve group 5 through the second check valve group 5. The low-pressure fluid in the piston catcher 2 passes through the circumferential flow hole 624 and the axial flow hole 625 provided in the catcher inner part 62, and pushes the spherical piston 20 into the second spiral pressure exchange chamber 3. In the second spiral pressure exchange chamber 3, the low-pressure fluid pushes the spherical piston 20 to replace the pressure relief fluid, and at the same time, the spherical piston 20 moves toward the fluid switcher 1 until the spherical piston 20 is captured by the piston catcher 4 on the side of the fluid switcher 1. The pressure relief fluid enters the fluid switcher 1 through the first fluid connector 612 of the catcher outer part 61 and the second fluid flow interface 110 of the fluid switcher 1 in sequence. In the fluid switcher 1, the fluid flows through the second annular fluid confluence chamber 1111 of the second connecting cylinder 111, enters the third axial through chamber 1071 of the second low-pressure cylinder 107, and is discharged through the second low-pressure fluid interface 108.

[0100] When the spherical piston 20 in the first spiral pressure exchange chamber 2 enters the piston catcher on the side of the first check valve group 4, or the spherical piston 20 in the second spiral pressure exchange chamber 3 enters the piston catcher on the side of the fluid switcher 1, the piston assembly moves downward under the push of external driving force, and the fluid switcher 1 enters the retreat working position. Figure 3 The fluid switcher 1 is shown in the retracted working position. In the retracted working position, the first spiral pressure exchange chamber 2 performs the discharge process of the pressure relief fluid, and the second spiral pressure exchange chamber 3 performs the pressurization process of the high-pressure fluid. When the spherical piston 20 in the first spiral pressure exchange chamber 2 enters the piston catcher on the side of the fluid switcher 1, or the spherical piston 20 in the second spiral pressure exchange chamber 3 enters the piston catcher on the side of the second check valve group 5, the piston assembly moves upward under the push of the external driving force, and the switcher enters the forward working position. This cycle repeats, and the first spiral pressure exchange chamber 2 and the second spiral pressure exchange chamber 3 alternately perform the pressurization process and the pressure relief process.

[0101] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments, which are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms of specific changes without departing from the scope of protection of the present invention and the claims, all of which fall within the scope of protection of the present invention.

Claims

1. A fluid switch, characterized in that: It includes a first low-pressure cylinder, a first connecting cylinder, a high-pressure cylinder, a second connecting cylinder, and a second low-pressure cylinder which are coaxially arranged in sequence from top to bottom; The first low-pressure cylinder is provided with a first axial through cavity, the inner diameter of the bottom end of the first axial through cavity gradually increases toward the port direction to form a first sealing surface; the top end of the first low-pressure cylinder is provided with a first upper end flange; the lower part of the first low-pressure cylinder is provided with a first lower end flange above the first sealing surface; the first low-pressure cylinder is connected to a first low-pressure fluid interface, the first low-pressure fluid interface is located between the first upper end flange and the first lower end flange, and is connected to the first axial through cavity; The first connecting cylinder is provided with a first annular fluid confluence cavity, the inner diameter of which is larger than the outer diameters of the first low-pressure cylinder and the high-pressure cylinder; the top and bottom ends of the first connecting cylinder are respectively provided with a first sealed connecting channel and a second sealed connecting channel, the inner diameters of the first sealed connecting channel and the second sealed connecting channel match the outer diameters of the first low-pressure cylinder and the high-pressure cylinder; the first connecting cylinder is connected with a first fluid flow interface, and the first fluid flow interface is connected with the first annular fluid confluence cavity; The high-pressure cylinder is provided with a second axial through cavity, and the inner diameters of the top and bottom ends of the second axial through cavity gradually increase toward the port direction, forming the second sealing surface and the third sealing surface; the upper and lower parts of the high-pressure cylinder are respectively provided with a second upper end flange and a second lower end flange, and the second upper end flange and the second lower end flange are located between the second sealing surface and the third sealing surface; sealing grooves are respectively provided on the outer rotating surface of the high-pressure cylinder between the second sealing surface and the second upper end flange, and between the second lower end flange and the third sealing surface; the high-pressure cylinder is connected with a high-pressure fluid interface, and the high-pressure fluid interface is located between the second upper end flange and the second lower end flange, and is communicated with the second axial through cavity; The second connecting cylinder is provided with a second annular fluid confluence chamber, the inner diameter of which is larger than the outer diameters of the high-pressure cylinder and the second low-pressure cylinder; the top and bottom ends of the second connecting cylinder are respectively provided with a third sealed connection channel and a fourth sealed connection channel, the inner diameters of the third sealed connection channel and the fourth sealed connection channel match the outer diameters of the high-pressure cylinder and the second low-pressure cylinder; the second low-pressure cylinder is connected with a second low-pressure fluid interface, and the second fluid flow interface is connected with the second annular fluid confluence chamber; The second low-pressure cylinder is provided with a third axial through cavity, the inner diameter of the top end of the third axial through cavity gradually increases toward the port direction to form a fourth sealing surface; the bottom end of the third axial through cavity is provided with a third lower end flange; the upper part of the second low-pressure cylinder is provided with a third upper end flange below the fourth sealing surface; the second connecting cylinder is connected with a second fluid flow interface, the second low-pressure fluid interface is located between the third upper end flange and the fourth lower end flange, and is connected with the third axial through cavity; The first low-pressure cylinder is sealed and connected to a driving end cover via a first upper end flange, and the second low-pressure cylinder is sealed and connected to a sealing end cover via a third lower end flange; There is a distance between the first low-pressure cylinder and the high-pressure cylinder, the first connecting cylinder is sleeved on the outside of the first low-pressure cylinder and the high-pressure cylinder, and is sealed and connected to the first lower end flange through the upper end face of the first connecting cylinder, and is sealed and connected to the second upper end flange through the lower end face of the first connecting cylinder, so that the first connecting cylinder seals and connects the first low-pressure cylinder and the high-pressure cylinder; There is a distance between the high-pressure cylinder and the second low-pressure cylinder, the second connecting cylinder is sleeved on the outside of the high-pressure cylinder and the second low-pressure cylinder, and is sealed and connected to the second lower end flange through the upper end face of the second connecting cylinder, and is sealed and connected to the third upper end flange through the lower end face of the second connecting cylinder, so that the second connecting cylinder seals and connects the high-pressure cylinder and the second low-pressure cylinder; A piston assembly is arranged in the through cavity formed by the first low-pressure cylinder, the high-pressure cylinder, the second low-pressure cylinder, the first low-pressure cylinder, and the second low-pressure cylinder, and the piston assembly reciprocates under the drive of the driving mechanism; The piston assembly comprises a driving rod, a first piston, a piston rod and a second piston which are coaxially connected in sequence from top to bottom; The upper portion of the driving rod passes through the through hole of the driving end cover and is connected to the driving mechanism; a dynamic seal is formed between the through hole of the driving end cover and the driving rod; The outer rotating surface of the first piston is provided with a plurality of first seal installation grooves, and the plurality of first seal installation grooves are installed with sealing rings to form a multi-stage dynamic seal between the first piston and the first low-pressure cylinder and the high-pressure cylinder; the outer rotating surface of the second piston is provided with a plurality of second seal installation grooves, and the plurality of second seal installation grooves are installed with sealing rings to form a multi-stage dynamic seal between the second piston and the high-pressure cylinder and the second low-pressure cylinder.

2. A fluid switch according to claim 1, characterized in that: The first low-pressure cylinder, the high-pressure cylinder, and the second low-pressure cylinder have the same outer diameter and the same inner diameter.

3. A fluid switch according to claim 1, characterized in that: The upper end surface and the lower end surface of the first connecting cylinder are respectively provided with blind bolt holes, and the upper end surface and the lower end surface of the second connecting cylinder are respectively provided with blind bolt holes.

4. A fluid switch according to claim 1, characterized in that: A sealing groove is provided on the outer rotating surface of the first low-pressure cylinder between the first lower end flange and the first sealing surface, and a sealing groove is provided on the outer rotating surface of the second low-pressure cylinder between the fourth sealing surface and the third upper end flange.

5. A fluid switch according to claim 1, characterized in that: The outer rotating surface of the first piston is provided with a plurality of first throttling grooves, and the plurality of first throttling grooves are respectively arranged between the two end surfaces of the first piston and the first sealing installation groove; the outer rotating surface of the second piston is provided with a plurality of first throttling grooves, and the plurality of second throttling grooves are respectively arranged between the two end surfaces of the second piston and the second sealing installation groove.

6. The fluid switch according to claim 1, characterized in that: The first piston is threadedly connected to the driving rod and the piston rod respectively, and the second piston is threadedly connected to the piston rod.

7. A fluid pressure energy recovery device, characterized in that: Comprising a fluid switcher as described in any one of claims 1 to 6; the first fluid flow interface of the fluid switcher is connected to the first end interface of the first spiral pressure exchange chamber through a piston catcher, and the second fluid flow interface of the fluid switcher is connected to the first end interface of the second spiral pressure exchange chamber through a piston catcher; the second end interface of the first spiral pressure exchange chamber is connected to the first check valve group through the piston catcher, and the second end interface of the second spiral pressure exchange chamber is connected to the second check valve group through the piston catcher; The first spiral pressure exchange chamber and the second spiral pressure exchange chamber are both configured as spiral pressure channels; A spherical isolation piston is disposed inside the first spiral pressure exchange chamber and the second spiral pressure exchange chamber. The spherical isolation piston is used to isolate two pressure exchange fluids and moves with the flow of the fluids. When the spherical isolation piston moves to the ends of the first spiral pressure exchange chamber and the second spiral pressure exchange chamber, it can be captured by the piston catcher, and the piston catcher is used to limit the stroke of the spherical isolation piston without blocking the flow channel.

8. A fluid pressure energy recovery device according to claim 7, characterized in that: The spiral pressure flow channel adopts a circular spiral or a rectangular spiral.

9. A fluid pressure energy recovery device according to claim 7, characterized in that: The piston trap is composed of a trap outer shell and a trap inner part, and the trap outer part and the trap inner part are sealed and connected; The trap outer part comprises a shell, the shell is provided with a first fluid connector, the first fluid connector is used to connect with the first fluid flow interface or the second fluid flow interface of the fluid switch; the shell is provided with a flow cavity, the flow cavity is open on the top surface of the shell, and is connected with the first fluid connector; The trap internals include a trap cage, the top of the trap cage is open, and the circumferential flow holes and the axial flow holes are respectively arranged on the circumference and bottom surfaces; the top opening of the trap cage is coaxially connected to the second fluid connector through a connecting flange; the second fluid connector is used to connect to the first end interfaces of the first spiral pressure exchange chamber and the second spiral pressure exchange chamber; The capture cage of the collector inner part is located in the flow cavity of the collector outer part, and the flow cavity is coaxially arranged with the capture cage to form an annular flow cavity; the collector inner part is sealed and connected to the top surface of the shell through a connecting flange.

10. A fluid pressure energy recovery device according to claim 7, characterized in that: The first check valve group and the second check valve group both include a three-way pipe, the three-way pipe having a first interface, a second interface and a third interface; the first interface is used to connect the piston catcher; the second interface is connected to the first straight pipe through the first check valve, and the first straight pipe is used for fluid outflow; the third interface is connected to the second straight pipe through the second check valve, and the second straight pipe is used for fluid inflow.

Images