Single-arc channel centrifugal pump

Abstract

This invention discloses a single-arc flow channel centrifugal pump, comprising a pump cover structure and a pump body structure. The pump body structure can be axially fitted into the pump cover structure, achieving mortise and tenon assembly through the rotational engagement of the toothed and grooved parts, eliminating the need for rivet connections. The pump body is equipped with single-arc arc-shaped blades forming an arc-shaped flow channel, with the inner and outer arcs arranged in opposite positions. Only two sets of coordinates are required for machining, avoiding interference from rib machining and improving the efficiency of fluid kinetic energy to pressure energy conversion. Furthermore, a pressure-driven self-locking structure is incorporated, utilizing the high pressure of the centrifugal pump outlet to drive the plunger rod. The area difference between the large and small cross-sections of the plunger rod creates a net clamping force, which, combined with a throttling damping orifice, achieves pressure buffering. The higher the working pressure, the stronger the locking force, suppressing loosening caused by high-speed vibration. This invention features a simple assembly process, low processing cost, high flow channel forming accuracy, and maintains connection reliability under all operating conditions, ensuring the centrifugal pump's delivery performance. It is suitable for disc centrifuges.

Description

Technical Field

[0001] This invention relates to the field of centripetal pump technology, and specifically to a single-circular-arc flow channel centripetal pump. Background Technology

[0002] A centrifugal pump is a unique liquid output device in a separator, typically installed inside the drum of a centrifuge or similar separation equipment. It acts as a liquid flow guide, directing liquid flow through its internal channels. This process changes the direction of the rotating liquid flow from tangential to near-radial, allowing the liquid to enter the impeller's central pipe from the pump chamber via the impeller edge. Simultaneously, it converts the liquid's kinetic energy into pressure energy, overcoming the resistance of the output pipe and driving the liquid outward. In the separation process of a separator, it plays a crucial role in delivering the separated liquid to subsequent equipment without external power. Existing centrifugal pumps generally consist of two parts: the pump body and the pump cover. Figure 1 As shown, the pump body and pump cover are fixedly connected by rivets. The pump cover is equipped with a rib structure to divide the internal flow channel of the centripetal pump into different chambers, and the flow channel profile is composed of a relatively complex curve.

[0003] However, due to limitations in current processing capabilities, coupled with the high precision requirements of the centrifugal pump itself for the fit between the pump body and the pump cover, existing structures exhibit numerous insurmountable defects during actual processing and use. In the riveting process between the pump body and the pump cover, due to limitations in processing space and technological conditions, the riveting quality of some structures is difficult to guarantee consistently, often resulting in loose riveting. This leads to a lack of tight fit between the pump body and the pump cover, leaving gaps at their mating surfaces. The presence of these gaps directly compromises the sealing and integrity of the internal flow channels of the centrifugal pump. Liquid leaks or becomes turbulent during transport, significantly reducing the pump's conveying capacity. The transported liquid foams and emulsifies due to severe disturbance, and the output back pressure of the centrifugal pump fails to meet design requirements, severely impacting the overall separation effect and operational stability of the separator.

[0004] Furthermore, during long-term operation, existing centrifugal pumps rely solely on the pre-tightening force provided by rivets to maintain the tightness of the connection between the pump body and the pump cover. However, centrifugal pumps operate inside a high-speed rotating drum, continuously subjected to the combined effects of centrifugal force, fluid pressure pulsation, and mechanical vibration. The riveted parts are prone to loosening under alternating loads, and wear occurs between the rivets and the riveting holes due to relative micro-movements. This causes the clearance between the pump body and the pump cover to gradually increase over time, further exacerbating the aforementioned problems of leakage, foaming, emulsification, and insufficient back pressure. Ultimately, this forces the equipment to be shut down for maintenance, increasing maintenance costs and reducing the continuous operation capability of the separation equipment.

[0005] For the reasons mentioned above, it is necessary to propose a centripetal pump with a single circular arc flow channel to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a centripetal pump with a single circular arc flow channel, addressing the deficiencies in the existing technology.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows: A single-circular-arc flow channel centripetal pump includes a pump cover structure. The pump cover structure has a columnar portion arranged along the axial direction, and a disc portion circumferentially arranged at the end of the columnar portion. It also includes a pump body structure sleeved on the pump cover structure. The pump body structure includes a sleeve portion and a flow channel disc. The sleeve portion is a cylindrical body, and the flow channel disc is arranged at the end of the sleeve portion. The sleeve portion is coaxially sleeved outside the columnar portion. The flow channel disc and the disc portion cooperate to form an impeller body. The pump cover structure has a snap-tooth portion, and the pump body structure has a snap-groove portion. When the pump body structure moves axially and is sleeved into the bottom end of the pump cover structure, the snap-tooth portion and the snap-groove portion are aligned. The pump body structure and the pump cover structure rotate relative to each other so that the snap-tooth portion and the snap-groove portion are engaged and assembled to form a centripetal pump.

[0008] Furthermore, the flow channel disk has multiple arc-shaped blades on the side facing the disk body, and the multiple arc-shaped blades are evenly distributed circumferentially, dividing the impeller body to form multiple arc-shaped flow channels.

[0009] Furthermore, the inner diameter of the sleeve portion is larger than the outer diameter of the column portion, forming an annular gap between the two. The outer wall of the sleeve portion is provided with multiple rib portions, which uniformly divide the annular gap into multiple axial cavities. The bottom end of the axial cavity is connected to the arc-shaped flow channel.

[0010] Furthermore, the inner arc of the flow channel of the arc-shaped blade is smaller than the outer arc of the flow channel, and the center of the inner arc is set at a different position from the center of the outer arc, so that the center of the inner arc is set further away from the axis than the center of the outer arc. This axis is the axis of the centripetal pump, so that the blade width at the proximal end of the arc-shaped blade is wider than that at the distal end, and the blade width of the arc-shaped blade gradually narrows from the proximal end to the center end.

[0011] Furthermore, the distal end of the arc-shaped blade is tangent to the outer circle of the flow channel disk.

[0012] Furthermore, the proximal end of the arc-shaped blade is provided with a positioning hole, and the disc body is provided with an alignment hole that matches the positioning hole. When the pump cover structure moves to the bottom of the pump body structure, the positioning hole and the alignment hole are misaligned. When the pump body structure and the pump cover structure rotate relative to each other, and the snap tooth part and the snap groove part are engaged in place, the positioning hole and the alignment hole are aligned.

[0013] Furthermore, it also includes a pressure-driven self-locking structure. Multiple self-locking structures are evenly distributed circumferentially along the surface of the cylindrical part. The self-locking structure includes a cavity structure formed in the surface of the cylindrical part. A plunger rod is provided in the cavity structure. One end of the cavity structure is connected to the high-pressure zone of the centripetal pump outlet, and the other end is set as an open groove that cooperates with the pump body structure. The pump body structure is provided with a push block that is inserted into the open groove. One end of the plunger rod extends into the open groove. During operation, the liquid in the high-pressure zone is injected into the cavity structure, and its force is applied to the plunger rod. The end of the plunger rod abuts against the push block and applies a tangential force to the pump body structure. This force causes the locking teeth and locking groove to lock tightly together.

[0014] Furthermore, the end of the cavity structure furthest from the open groove is designated as a sealed cavity. This sealed cavity is connected to the high-pressure zone of the pump outlet via a pressure supply pipe axially arranged along the inner surface of the sleeve. The sealed cavity is arranged in an L-shape with the pressure supply pipe. The end of the pressure supply pipe connected to the sealed cavity is provided with a throttling damping orifice. One end of the plunger rod is placed inside the sealed cavity (preferably with a large cross-section), and the other end protrudes from the sealed cavity and is placed inside the open groove (preferably with a small cross-section, the large cross-section having a larger cross-sectional area than the small cross-section). The pressure supply pipe allows high-pressure liquid to slowly enter the sealed cavity through the throttling damping orifice during operation, but without instantly filling it. When the centripetal pump starts working and the pressure in the outlet zone increases, the high-pressure liquid enters the sealed cavity through the throttling damping orifice. The pressure acts on the large cross-section end of the plunger rod, providing thrust, which acts on the push block along the plunger rod.

[0015] Furthermore, the plunger rod is positioned at one end of the sealed cavity with a large cross-section, and at the other end of the plunger rod located in the open groove with a small cross-section. The cross-sectional area of ​​the large cross-section end is larger than that of the small cross-section end.

[0016] Furthermore, the flow channel plate is provided with mounting holes, and the pusher is inserted into the open groove through the mounting holes, with the end of the pusher fixed on the mounting holes.

[0017] The advantages and beneficial effects of this invention are as follows: 1. Reliable connection and easy assembly: The pump body and pump cover adopt a self-connection method of mortise and tenon rotation interlocking to replace the traditional riveting, which fundamentally eliminates problems such as weak riveting, gaps in fit and the resulting decrease in conveying capacity, liquid foam emulsification and insufficient back pressure. At the same time, the ribs are moved to the outer wall of the pump body sleeve, avoiding the processing interference between the ribs and the riveting process and simplifying the production process.

[0018] 2. High efficiency and economical processing: The single circular arc flow channel design, with both the inner and outer sides of the flow channel being circular sections, requires only two coordinate points to complete the processing, effectively reducing processing costs and improving flow channel consistency; combined with the displaced inner and outer circular arcs, the gradual change in blade width, and the tangential setting at the distal end, the liquid flow guidance is smoother, and the conversion of kinetic energy into pressure energy is more complete.

[0019] 3. Adaptive locking, tightening with rotation: A self-locking structure driven by the high pressure of the centrifugal pump's own outlet is added. Through the pressure relief of the throttling damping orifice, the amplification of the force at the large and small cross sections of the plunger rod, and the dual effects of pressure difference and area difference, the plunger rod is always pressed against the push block and a tangential preload is applied to the pump body. The higher the working pressure, the tighter the locking, effectively preventing loosening and wear under high-speed operation. It is maintenance-free and reliable under all working conditions. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the longitudinal section of a centripetal pump in the prior art; Figure 2 This is a schematic diagram of the longitudinal section of the centripetal pump with a single circular arc flow channel in this invention; Figure 3 These are cross-sectional and top views of the pump cover structure in this invention; Figure 4 These are the top view and cross-sectional view of the pump body structure in this invention; Figure 5 This is a schematic diagram of the self-locking structure in this invention; Figure 6 This is a diagram showing the arrangement of the pressure taps in the self-locking structure of this invention; In the diagram: 1. Pump cover structure; 2. Pump body structure; 3. Rivet; 4. Column part; 5. Disc part; 6. Sleeve part; 7. Flow channel disc; 8. Impeller body; 9. Gear part; 10. Groove part; 11. Arc-shaped blade; 12. Annular gap; 13. Rib part; 14. Inner arc; 15. Outer arc; 16. Proximal end; 17. Positioning hole; 18. Alignment hole; 19. Cavity structure; 20. Piston rod; 21. Open groove part; 22. Push block; 23. Tangential force; 24. Throttling damping hole; 25. Large cross-section end; 26. Small cross-section end; 27. Self-locking structure; 28. Pressure tapping pipe. Detailed Implementation

[0021] The specific embodiments of the present invention will be further described below with reference to examples. These examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0022] Example 1: A single-circular-arc flow channel centrifugal pump, as a unique liquid output device in a separator, guides liquid flow through its internal flow channel. This achieves two key transformations: firstly, it changes the flow direction, shifting the tangential flow of the rotating liquid to a radial flow, allowing the liquid to enter the impeller's central pipe from the pump chamber via the impeller edge; secondly, it converts the liquid's kinetic energy into pressure energy to overcome resistance and drive the liquid output. Thus, it plays a crucial role in the separator's separation process, transporting liquid to other equipment without requiring external power. Figure 2-4 As shown, the single-circular arc flow channel centrifugal pump includes a pump cover structure 1. The pump cover structure 1 has a column part 4 arranged along the axial direction. The column part 4 is a cylindrical tube structure. Its axial passage can serve as a feed hole for materials to enter the disc centrifuge along the axial direction. A disc part 5 is arranged circumferentially at the end of the column part 4, so that the column part 4 is perpendicular to the center position of the disc part 5.

[0023] It also includes a pump body structure 2 fitted onto the pump cover structure 1. The pump body structure 2 includes a sleeve portion 6 and a flow channel plate 7. The sleeve portion 6 is a cylindrical body, and the flow channel plate 7 is provided at the end of the sleeve portion 6. The sleeve portion 6 as a whole is also a cylindrical structure with a length less than that of the cylindrical body portion 4. The sleeve portion 6 is vertically arranged at the center of the flow channel plate 7. The sleeve portion 6 is coaxially fitted onto the cylindrical body portion 4. The flow channel plate 7 and the plate body portion 5 cooperate to form an impeller body 8. The diameter of the flow channel plate 7 is similar to that of the plate body portion 5. After installation, the flow channel plate 7 and the plate body portion 5 are set parallel to each other at a certain distance, so that the liquid flow is pumped through the formed impeller body 8 when rotating.

[0024] Unlike traditional centrifugal pumps that use rivets 3 to fix the pump body and pump cover together, this embodiment has a snap-tooth portion 9 on the pump cover structure 1 and a snap-groove portion 10 on the pump body structure 2. When the pump body structure 2 moves axially and fits into the bottom end of the pump cover structure 1, during installation, the pump body structure 2 is inserted downwards from the top end of the column portion 4 through the sleeve portion 6. When the pump body structure 2 is installed to the bottom, the snap-tooth portion 9 and the snap-groove portion 10 are aligned. Then, the pump body structure 2 and the pump cover structure 1 are controlled to rotate relative to each other, thereby aligning the snap-tooth portion 9 and the snap-groove portion 10. The snap-fit ​​design allows the pump cover structure 1 and the pump body structure 2 to be joined together to form a centripetal pump. This mortise and tenon self-connection fixing method solves the problems caused by the traditional structure requiring the pump cover and body to be connected by rivets 3 from the design level. It avoids the drawbacks caused by limited processing, such as weak rivet connection, poor fit between the pump body and pump cover, gaps that lead to reduced conveying capacity, foaming and emulsification of the conveyed liquid, and insufficient back pressure. At the same time, it saves the manpower required for the riveting process and simplifies the production process.

[0025] In order to form a flow channel structure to guide the liquid flow inside the centripetal pump, the flow channel disk 7 is provided with multiple arc-shaped blades 11 on the side facing the disk body 5. The multiple arc-shaped blades 11 are evenly distributed around the circumference, dividing the impeller body 8 into multiple arc-shaped flow channels. The liquid completes the conversion of flow direction and energy form in the process of flowing from the outer edge to the center in the arc-shaped flow channel.

[0026] Furthermore, the inner diameter of the sleeve portion 6 is larger than the outer diameter of the cylindrical portion 4, forming an annular gap 12 between them. The outer wall of the sleeve portion 6 is provided with multiple rib portions 13, which uniformly divide the annular gap 12 into multiple axial cavities. The bottom end of the axial cavity is connected to the arc-shaped flow channel. Here, the rib portions 13 are set on the outer wall of the sleeve portion 6 of the pump body structure 2, thereby avoiding the difficulties in machining the ribs and the interference problem, which would cause the centripetal pump flow channel to fail to meet the design requirements. The rib portions 13 divide the annular gap 12 into multiple axial cavities, so that the liquid is guided and rectified by the axial cavities before entering the arc-shaped flow channel, thereby increasing the output capacity of the centripetal pump.

[0027] In terms of flow design, this embodiment adopts a single circular arc flow channel design, that is, both the inner and outer sides of the flow channel are circular sections, forming the processing structure of a single circular arc flow channel centripetal pump. During the processing, only two coordinate points are needed to complete the arc, which effectively reduces the processing cost.

[0028] In the specific configuration of the arc-shaped blade 11, the inner arc 14 of the flow channel is smaller than the outer arc 15 of the flow channel. The center of the inner arc 14 and the center of the outer arc 15 are set out of position, so that the center of the inner arc 14 is far away from the axis compared with the center of the outer arc 15. This axis is the axis of the centripetal pump, so that the blade width at the proximal end 16 of the arc-shaped blade 11 is wider than that at the distal end, and the blade width of the arc-shaped blade 11 gradually narrows from the proximal end 16 to the center end, so that the arc-shaped blade 11 has a certain width at the proximal end 16, which facilitates the setting of structures such as the groove part 10 at the proximal end 16. This design of the inner and outer arcs being out of position and the blade width gradually changing makes the flow channel cross section present a gradual characteristic along the liquid flow direction, which can better adapt to the change law of flow velocity and pressure when the liquid flows from the outer edge to the center, making the conversion of kinetic energy into pressure energy more stable and efficient. The distal end of the arc-shaped blade 11 is tangent to the outer circle of the flow channel disk 7. The tangent design of the distal end makes the inlet smoother when the liquid enters the arc-shaped flow channel from the pump chamber, reducing the impact and eddy current loss when the liquid enters the flow channel, which is beneficial to improving the delivery efficiency and output back pressure of the centripetal pump.

[0029] Furthermore, to ensure precise alignment between the pump body structure 2 and the pump cover structure 1 during rotational engagement, a positioning hole 17 is provided through the proximal end 16 of the arc-shaped blade 11, and an alignment hole 18 is provided on the disc body 5 to mate with the positioning hole 17. When the pump cover structure 1 moves to the bottom of the pump body structure 2, the positioning hole 17 and the alignment hole 18 are misaligned, and the pump body structure 2 and the pump cover structure 1 rotate relative to each other. When the snap tooth part 9 and the snap groove part 10 are engaged, the positioning hole 17 and the alignment hole 18 are aligned. The matching relationship between the positioning hole 17 and the alignment hole 18 serves as a visual indicator of engagement and can also be used to further lock the relative circumferential position between the pump body structure 2 and the pump cover structure 1 by inserting pins or other means after engagement, preventing the centrifugal pump from rotating and loosening due to vibration or liquid flow reaction force during operation. The centripetal pump is installed on the inlet and outlet device of the separator. The top of the pump cover structure 1 is provided with a threaded structure. Other parts are installed on the threaded structure on the top of the pump cover. By tightening the centripetal pump, the flow channel plate 7 can be fixed to the plate body 5, thus completing the overall installation of the centripetal pump.

[0030] In this embodiment, the single-arc flow channel centripetal pump forms a complete and coordinated system from installation and fixation to flow channel guidance and energy conversion through the split tenon and tenon joint connection between the pump cover structure 1 and the pump body structure 2, the separation of the axial cavity by the pump body side rib section 13, the construction of the flow channel inside the impeller body 8 by the single-arc arc blade 11, and the control of the flow channel cross section by the inner and outer arc gradually changing blade width. The rotating engagement of the toothed part 9 and the grooved part 10 avoids axial displacement and replaces the traditional riveting with rivets 3, fundamentally eliminating the problems of weak riveting and gaps in the fit. At the same time, it allows the rib part 13 to be freely set on the outer wall of the pump body sleeve part 6 without being interfered with by the riveting process. The axial cavity formed by the rib part 13 is connected to the beginning and end of the arc-shaped flow channel, so that the liquid is first rectified axially and then enters the arc-shaped flow channel to complete the centripetal delivery, which improves the output capacity. The single arc flow channel design takes into account both the liquid flow guiding performance and the processing economy. The dislocation of the inner and outer arcs, the gradual change of the blade width, and the tangential setting of the distal end further optimize the liquid flow state in the flow channel, making the conversion of kinetic energy into pressure energy more complete.

[0031] This embodiment avoids problems such as reduced conveying capacity, liquid foam emulsification, and insufficient back pressure caused by riveting defects. It eliminates interference from rib processing, ensuring the flow channel meets design requirements, reducing flow channel processing costs, simplifying production and assembly processes, improving the output capacity and conveying efficiency of the centripetal pump, and ensuring reliable installation and positioning, preventing loosening during operation.

[0032] Example 2: In Embodiment 1, the pump cover structure 1 and the pump body structure 2 are combined and fixed together by the meshing of the snap teeth 9 and the snap groove 10. During installation, the pump body structure 2 rotates relative to the pump cover structure 1 to align the positioning hole 17 with the alignment hole 18. Bolts, positioning pins and other structures can be inserted to restrict the circumferential relative rotation of the two. However, there is an assembly gap between the bolt inserted into the positioning hole 17 and the positioning hole 17 and the alignment hole 18. Under long-term operation and repeated impacts of high speed and high pressure, vibration and wear are easily caused. The reason is that under this assembly gap, the flow channel plate 7 and the plate body 5 rotate slightly relative to each other. In particular, when the centrifugal pump switches between low speed and high speed, the flow channel plate 7 and the plate body 5 repeatedly vibrate, causing the structure to loosen.

[0033] Specifically, such as Figure 5 , 6 As shown, based on the single-circular arc flow channel centripetal pump described in Example 1, this embodiment further adds a pressure-driven self-locking structure. Multiple self-locking structures are evenly distributed along the circumferential surface of the column part 4 to solve the problem that the pump body structure 2 and the pump cover structure 1 may loosen circumferentially and have reduced tightness of engagement under high-speed rotation and liquid flow pulsation conditions when the mechanical engagement between them relies solely on the snap teeth 9 and the snap groove 10. The self-locking structure includes a cavity structure 19 formed in the surface of the column part 4. A plunger rod 20 is provided in the cavity structure 19. One end of the cavity structure 19 is connected to the high-pressure zone of the centripetal pump outlet through a connecting pipe 28, and the other end is set as an open groove part 21 that cooperates with the pump body structure 2. The pump body structure 2 is provided with a push block 22 that is placed in the open groove part 21. One end of the plunger rod 20 extends into the open groove. During operation, the liquid in the high-pressure zone is injected into the cavity structure 19 and its force is applied to the plunger rod 20. The end of the plunger rod 20 abuts against the push block 22 and applies a tangential force 23 to the pump body structure 2. This force causes the locking tooth part 9 and the locking groove part 10 to lock tightly together. The power source of this self-locking structure does not come from an external hydraulic system or elastic element, but is directly taken from the liquid pressure in the high-pressure zone of the centrifugal pump during its own operation. That is, while the centrifugal pump realizes liquid flow and converts kinetic energy into pressure energy, the high-pressure liquid generated by the centrifugal pump is introduced in reverse into the cavity structure 19 to drive the plunger rod 20 to complete the locking action, forming a self-driven adaptive locking mechanism of "delivery is locking, and the higher the pressure, the tighter the locking". This is fundamentally different from the traditional approach of relying on interference fit, rivet 3 riveting or spring preload to maintain tight connection.

[0034] To ensure that the high-pressure liquid can smoothly and controllably drive the plunger rod 20, the end of the cavity structure 19 away from the open groove 21 is designated as a sealed cavity. This sealed cavity is connected to the high-pressure zone of the pump outlet via a pressure supply pipe axially arranged along the inner surface of the sleeve 6. The arrangement of the cavity structure 19 and the pressure supply pipe forms an L-shape. This L-shaped pipe arrangement fully utilizes the radial and axial space between the column portion 4 and the sleeve portion 6, allowing the self-locking structure to be embedded inside the pump body without increasing the external dimensions of the centrifugal pump. The end of the pressure supply pipe connecting to the sealed cavity is provided with a throttling damping orifice 24. One end of the plunger rod 20 is placed within the sealed cavity, preferably as a large-section end 25. The other end extends out of the sealed cavity and is placed within the open groove 21, preferably as a small-section end 26. The cross-sectional area of ​​the large-section end 25 is larger than that of the small-section end 26. The pressure supply pipe allows high-pressure liquid to slowly enter the sealed cavity through the throttling damping orifice 24 during operation, but it will not fill it instantly. When the centrifugal pump starts working and the pressure in the outlet area increases, the high-pressure liquid enters the sealed cavity through the throttling damping orifice 24. The pressure acts on the large cross-section end 25 of the plunger rod 20 to provide thrust. The thrust acts on the push block 22 along the plunger rod 20. The delayed buffering effect produced by the setting of the throttling damping orifice 24 here is as follows: At the moment of starting the centrifugal pump, the pressure in the outlet area rises suddenly. If the high-pressure liquid directly rushes into the sealing cavity, it will cause the plunger rod 20 to be violently pushed out instantly, generating an impact tangential force on the push block 22. This may cause impact wear between the locking teeth 9 and the locking groove 10, or even circumferential vibration of the pump body structure 2. However, the throttling damping orifice 24 restricts the flow rate of the liquid into the sealing cavity, so that the pressure in the sealing cavity gradually increases over time. The plunger rod 20 is pushed out at a slow speed and abuts against the push block 22. The locking force is gradually built up, effectively avoiding the starting impact. Conversely, when the centrifugal pump stops, the pressure in the outlet area drops rapidly. The high-pressure liquid in the sealing cavity slowly flows back and is released through the throttling damping orifice 24. The plunger rod 20 also slowly retracts, avoiding the instantaneous disappearance of the locking force, which would cause relative surging impact between the pump body structure 2 and the pump cover structure 1. This structure forms a two-way buffering characteristic of slow locking at start-up and slow release at stop.

[0035] In addition, since the plunger rod 20 is designed with a large cross-section end 25 and a small cross-section end 26 at both ends, the plunger rod 20 is positioned at the sealed cavity end with a large cross-section end 25 and at the open groove end 21 with a small cross-section end 26. The cross-sectional area of ​​the large cross-section end 25 is larger than that of the small cross-section end 26. This differentiated cross-section design is not only to obtain greater thrust at the large cross-section end 25 to achieve force amplification, but its deeper design intention is to use the inherent difference in the cross-sectional areas of the two ends to construct a "pressure difference-area difference" dual action of constant clamping mechanism. Specifically, the plunger rod 20 is not in an ideal unidirectional force state with one end pressurized and the other end completely unpressurized within the cavity structure 19. The open groove 21 where its small cross-section end 26 is located is connected to the internal space of the pump body structure 2. During the operation of the centrifugal pump, a certain amount of liquid pressure will inevitably exist in the open groove 21. This pressure acts on the small cross-section end 26 of the plunger rod 20 and generates a reverse thrust opposite to the thrust of the large cross-section end 25. If the cross-sectional areas of the two ends of the plunger rod 20 are equal, then when the liquid pressure at both ends tends to be balanced, the thrusts at both ends cancel each other out, and the plunger rod 20 will lose its clamping effect on the push block 22. The tightness of the engagement between the snap teeth 9 and the snap groove 10 will decrease accordingly. However, in this design, the two ends of the plunger rod 20 are set as a large cross-section end 25 and a small cross-section end 26 with unequal cross-sectional areas. According to the force calculation formula F=p×S, even in the extreme case where the liquid pressure at both ends is exactly the same, the thrust generated by the large cross-section end 25 (F 大 =p×S 大 The force is also always greater than the reverse thrust (F) generated by the small section end 26. 小 =p×S 小 The resultant force of the two is ΔF = p × (S) 大 -S 小 The piston rod 20 is always aligned with the small section end 26 along its axis, meaning it is always pushed against the push block 22. This means that as long as the open groove 21 and the sealed cavity have the same liquid pressure, the piston rod 20 can obtain a residual preload force pointing towards the push block 22 due to the area difference. This ensures that the end of the piston rod 20 is always against the push block 22 and will not detach from the push block 22 due to the equal pressure at both ends, so that the snap tooth 9 and the snap groove 10 always maintain a tight fit within the entire pressure range.

[0036] When the centrifugal pump is operating normally, the sealed cavity connected to the large cross-section end 25 is connected to the high-pressure zone of the centrifugal pump outlet through the pressure supply pipe and the throttling damping orifice 24, while the open groove 21 at the small cross-section end 26 is connected to the relatively low-pressure area inside the pump body structure 2. At this time, there is not only a difference in cross-sectional area between the two ends of the plunger rod 20, but also a significant pressure difference. The large cross-section end 25 bears the high-pressure liquid pressure p in the high-pressure zone of the outlet. 高 The small cross-section end 26 bears the relatively low pressure p inside the open groove 21. 低 , and p高 >p 低 Under this operating condition, the net thrust ΔF obtained by the plunger rod 20 is p 高 ×S 大 -p 低 ×S 小 The net thrust is composed of two parts: "high pressure acting on a large cross-section" and "low pressure acting on a small cross-section". The two factors are superimposed, on the one hand, high pressure p 高 The voltage itself is relatively large, and on the other hand, this high voltage acts on the larger cross-sectional end for 25 seconds. 大 The product of the two generates a very large positive thrust; while the opposite side has a lower pressure p. 低 Acting on the smaller cross-sectional end 26S 小 The reverse thrust is doubly weakened, so the net thrust ΔF is much greater than the residual preload generated by the area difference alone. This causes the plunger rod 20 to press against the push block 22 with a greater force, thereby applying a greater tangential force 23 to the pump body structure 2, causing the toothed part 9 and the grooved part 10 to engage with each other with a higher preload. This design creates a bidirectional force enhancement effect of "high pressure end amplification and low pressure end reduction" during operation. The pressing force of the plunger rod 20 increases significantly with the increase of the centrifugal pump's working pressure. The higher the back pressure of the centrifugal pump output and the more severe the conveying conditions, the more firmly the plunger rod 20 presses against the push block 22, and the tighter the engagement of the toothed part 9 and the grooved part 10. This fundamentally avoids the problem of loosening caused by high-speed rotational vibration, fluid flow pulsation, and long-term wear. At the same time, it effectively suppresses wear caused by small relative displacements between the engagement surfaces, extending the service life and operational reliability of the centrifugal pump.

[0037] The plunger rod 20 has a large cross-section end 25 at one end of the sealed cavity and a small cross-section end 26 at the other end of the open groove 21. The cross-sectional area of ​​the large cross-section end 25 is larger than that of the small cross-section end 26. This difference in cross-sectional area essentially constitutes a force amplification mechanism. According to the principle of hydrostatic transmission, the axial thrust generated by the liquid pressure acting on the large cross-section end 25 is equal to the liquid pressure multiplied by the cross-sectional area of ​​the large cross-section end 25. This thrust is rigidly transmitted to the small cross-section end 26 through the plunger rod 20 and acts on the pusher block 22. With a smaller cross-sectional area, the end contact pressure is higher under the same thrust, which can more concentratedly apply tangential force 23 to the push block 22. This means that even if the liquid pressure in the high-pressure zone of the outlet is not very high, it can still generate a sufficiently large locking thrust after the area is amplified by the large cross-section end 25, thereby ensuring that the locking tooth part 9 and the locking groove part 10 remain tightly engaged in the entire operating range. This force amplification effect greatly enhances the adaptability of the self-locking structure to the working pressure of the centrifugal pump, and a reliable locking effect can be obtained even in the low-pressure start-up stage or low-load operating conditions.

[0038] The flow channel plate 7 is provided with mounting holes. The push block 22 is inserted into the open groove 21 through the mounting holes, and the end of the push block 22 is fixed on the mounting holes. This insertion-type push block 22 installation method makes the assembly and replacement of the push block 22 very convenient. During installation, the pump body structure and the pump cover structure are rotated relative to each other at a certain angle so that the snap teeth and snap grooves are engaged in place. Then, the push block is inserted into the mounting holes so that its end is inserted into the open groove and can contact the small cross-section end. At the same time, the end of the push block 22 is fixed on the mounting holes of the flow channel plate 7, which ensures the connection rigidity between the push block 22 and the pump body structure 2, so that the tangential force applied by the plunger rod 20 can be reliably transmitted to the entire pump body structure 2 and finally converted into the circumferential clamping force between the snap teeth 9 and the snap groove 10.

[0039] The self-locking structure of this embodiment transforms the working medium pressure of the centrifugal pump itself, which was originally considered an "output result," into a "control input" that maintains the tightness of its own structure, thus achieving functional self-consistency and closed-loop. Multiple self-locking structures are evenly distributed circumferentially along the surface of the column part 4, so that the tangential force 23 applied by each plunger rod 20 to the corresponding push block 22 is uniform and consistent in the circumferential direction. Together, they push the pump body structure 2 to generate a uniform circumferential pre-tightening tendency relative to the pump cover structure 1. This tendency is exactly consistent with the fastening direction of the fastening tooth part 9 and the fastening groove part 10, so that the fastening surface on the entire circumference is uniformly pressed and tightly fitted, avoiding the off-center load and local gap caused by unilateral locking. More importantly, the self-locking structure and the mortise and tenon fastening connection in Embodiment 1 form a synergistic effect: the mortise and tenon fastening provides the initial mechanical positioning and basic connection during assembly, while the self-locking structure dynamically supplements and enhances the tightness of the fastening according to the working pressure during operation. When the two are combined, the higher the speed of the centrifugal pump, the greater the delivery flow rate, and the higher the liquid back pressure, the greater the tangential locking force applied by the self-locking structure, and the tighter the fastening teeth 9 and the fastening groove 10 will be. This positive feedback characteristic of "the more severe the working conditions, the more reliable the connection" is not available in the traditional fixed pre-tightening connection method. Furthermore, the delayed buffering of the throttling damping orifice 24 and the force amplification of the large and small cross-section ends 26 work together to enable the self-locking structure to obtain sufficient locking force and smooth, impact-free operation in the low-pressure stage. In the high-pressure stage, the locking is further enhanced without overload impact. The entire structure requires no external power source, no electrical control components, and no precision elastic parts. It relies entirely on the hydraulic energy of the centrifugal pump itself and the pure mechanical structure to achieve adaptive locking. It has significant advantages such as simple structure, reliable operation, maintenance-free operation, and adaptability to all working conditions. At the same time, it fundamentally eliminates a series of problems caused by loose fastening, such as gaps between the pump body and pump cover, which in turn lead to a decrease in delivery capacity, liquid foam emulsification, and insufficient back pressure.

[0040] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A centripetal pump with a single circular arc flow channel, characterized in that, The system includes a pump cover structure, which has an axially oriented cylindrical portion and a circumferentially oriented disc portion at the end of the cylindrical portion. It also includes a pump body structure fitted onto the pump cover structure. The pump body structure includes a sleeve portion and a flow channel disc. The sleeve portion is a cylindrical body, and the flow channel disc is located at the end of the sleeve portion. The sleeve portion is coaxially fitted onto the cylindrical portion. The flow channel disc and the disc portion cooperate to form an impeller. The pump cover structure has a snap-tooth portion, and the pump body structure has a snap-groove portion. When the pump body structure moves axially and fits into the bottom end of the pump cover structure, the snap-tooth portion aligns with the snap-groove portion. The pump body structure and the pump cover structure rotate relative to each other, causing the snap-tooth portion and the snap-groove portion to engage and assemble into a radial pump.

2. The centripetal pump with a single circular arc flow channel according to claim 1, characterized in that, The flow channel disk has multiple arc-shaped blades on the side facing the disk body. The multiple arc-shaped blades are evenly distributed circumferentially, dividing the impeller body into multiple arc-shaped flow channels.

3. A centripetal pump with a single circular arc flow channel according to claim 2, characterized in that, The inner diameter of the sleeve part is larger than the outer diameter of the column part, so that an annular gap is formed between the two. The outer wall of the sleeve part is provided with multiple ribs, which uniformly divide the annular gap into multiple axial cavities. The bottom end of the axial cavity is connected to the arc-shaped flow channel.

4. A centripetal pump with a single circular arc flow channel according to claim 2, characterized in that, The inner arc of the flow channel of the arc-shaped blade is smaller than the outer arc of the flow channel. The center of the inner arc is set at a different position from the center of the outer arc, so that the center of the inner arc is further away from the axis than the center of the outer arc. This makes the blade width at the proximal end of the arc-shaped blade wider than that at the distal end, and the blade width of the arc-shaped blade gradually narrows from the proximal end to the center end.

5. A centripetal pump with a single circular arc flow channel according to claim 2, characterized in that, The distal end of the arc-shaped blade is tangent to the outer circle of the flow channel plate.

6. A centripetal pump with a single circular arc flow channel according to claim 4, characterized in that, The proximal end of the arc-shaped blade is provided with a positioning hole, and the disc body is provided with an alignment hole that matches the positioning hole. When the pump cover structure moves to the bottom of the pump body structure, the positioning hole and the alignment hole are misaligned. When the pump body structure and the pump cover structure rotate relative to each other, and the snap tooth part and the snap groove part are engaged in place, the positioning hole and the alignment hole are aligned.

7. A centripetal pump with a single circular arc flow channel according to claim 1, characterized in that, It also includes a pressure-driven self-locking structure, with multiple self-locking structures evenly distributed circumferentially along the surface of the cylindrical part. The self-locking structure includes a cavity structure formed within the surface of the cylindrical part, and a plunger rod is provided inside the cavity structure. One end of the cavity structure is connected to the high-pressure zone of the centripetal pump outlet, and the other end is set as an open groove that cooperates with the pump body structure. The pump body structure is provided with a push block that is inserted into the open groove. During operation, the liquid in the high-pressure zone is injected into the cavity structure, and its force is applied to the plunger rod. The end of the plunger rod abuts against the push block, applying a tangential force to the pump body structure. This force causes the locking teeth and locking groove to lock tightly together.

8. A centripetal pump with a single circular arc flow channel according to claim 7, characterized in that, The cavity structure is configured as a sealed cavity at the end away from the open groove. The sealed cavity is connected to the high-pressure zone of the pump outlet through a pressure supply pipe arranged axially along the inner surface of the sleeve. The end of the pressure supply pipe connected to the sealed cavity is provided with a throttling damping hole. One end of the plunger rod is placed in the sealed cavity, and the other end extends out of the sealed cavity and is placed in the open groove.

9. A centripetal pump with a single circular arc flow channel according to claim 8, characterized in that, The plunger rod is positioned at one end of the sealed cavity with a large cross-section, and at the other end of the plunger rod located in the open groove with a small cross-section. The cross-sectional area of ​​the large cross-section end is larger than that of the small cross-section end.

10. A centripetal pump with a single circular arc flow channel according to claim 7, characterized in that, The flow channel plate is provided with mounting holes, and the pusher is inserted into the open groove through the mounting holes, with the end of the pusher fixed on the mounting holes.

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