Impeller and centrifugal booster pump

Abstract

The invention provides an impeller and a centrifugal booster pump. The impeller comprises a cover plate, and an oil inlet is formed in the cover plate; the bottom plate and the cover plate are correspondingly arranged at an interval to form a cylindrical structure; the blades are connected between the cover plate and the bottom plate, and the adjacent blades are arranged at intervals to form an oil outlet; the radial extension lines of the projections of the blades on the bottom plate meet the exponential function y = aebx, a ranges from 1.35 to 1.95, and b ranges from 0.13 to 0.16. The centrifugal booster pump comprises a pump body, a main shaft, a rear cover and an impeller, the rear cover is fixed at the axial rear end of the pump body to form an axial through structure, the rear cover is provided with an oil suction port, a volute chamber is arranged in the pump body, the pump body is provided with an oil discharge port corresponding to the volute chamber, the impeller is arranged in the volute chamber, the main shaft is axially arranged in the pump body, and the main shaft is in transmission connection with the impeller. On the basis of ensuring the quality of hydraulic oil, the pressurizing effect and the oil conveying efficiency are improved, so that the oil suction requirement of the hydraulic pump is met, and the hydraulic pump has the characteristics of simple structure and low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of oil pumps, and in particular to an impeller and a centrifugal booster pump. Background Art

[0002] At present, booster pumps often use water pumps and gear pumps. The water pump is a simple pump body designed for water media. The blades of the water pump are thin, and the gap between the upper and lower cover plates is very small. When the impeller rotates at high speed, it will form a shear flow with a shear rate of up to tens of thousands per second. If the water pump is used as a booster pump for hydraulic oil, its long-term high shear operation will gradually deteriorate its performance and greatly shorten its life. This is because the viscosity of hydraulic oil is 40-50 times that of water. When the water pump is used as a booster pump for hydraulic oil, the hydraulic oil is forced to perform high-speed shear motion, causing it to be "torn" and deteriorate, thereby generating cavitation inside the hydraulic oil, that is, shear cavitation, so that there is a large amount of free air in the hydraulic oil, which destroys the continuity of the hydraulic oil, and then greatly reduces the effective output flow of the water pump under high-speed shear conditions, resulting in very low oil delivery efficiency and difficulty in meeting the oil suction requirements of the hydraulic pump.

[0003] The gear pump is a positive displacement pump. When used as a booster pump for a hydraulic pump, the displacement must be greater than that of the hydraulic pump to meet the hydraulic pump's oil suction requirements, which results in a high cost. Moreover, once the gear pump is damaged, not only will the hydraulic pump be unable to absorb oil, but it will also cause the hydraulic pump to inhale air and be damaged, which results in a high safety risk in the use of the hydraulic pump.

[0004] Based on this, there is an urgent need to provide a booster pump to solve the problems of hydraulic oil deterioration, low efficiency and low cost. Summary of the invention

[0005] In order to overcome at least one of the defects described in the above-mentioned prior art, the present invention provides an impeller and a centrifugal booster pump, which improves the boosting effect and oil delivery efficiency on the basis of ensuring the quality of hydraulic oil, thereby meeting the oil suction demand of the hydraulic pump, and has the characteristics of simple structure and low cost.

[0006] A first aspect of the present invention provides an impeller, comprising:

[0007] A cover plate, wherein an oil inlet is provided on the cover plate;

[0008] The bottom plate and the cover plate are arranged at corresponding intervals to form a cylindrical structure;

[0009] A plurality of blades are connected between the cover plate and the bottom plate, and adjacent blades are spaced apart to form an oil outlet;

[0010] The radial extension line of the blade projection on the base plate satisfies the exponential function y = ae bx The changing law of a is 1.35-1.95, and the value of b is 0.13-0.16.

[0011] As an optional embodiment, in the first aspect of the present invention, the blade includes a first surface and a second surface arranged circumferentially at intervals, the first surface and the second surface both extend radially, and the projections of the first surface and the second surface on the bottom plate both satisfy the exponential function y=ae bx The changing law of a is 1.35-1.95, and the value of b is 0.13-0.16.

[0012] As an optional embodiment, in the first aspect of the present invention, the distance between the corresponding positions of the first surface and the second surface is the thickness d of the blade, the diameter of the circular structure formed by the plurality of blades is the diameter D of the impeller, and the ratio of D / d satisfies (5-10):1.

[0013] As an optional embodiment, in the first aspect of the present invention, the ends of the first surface and the second surface close to the impeller axis are connected by a transition surface, and the transition surface is an arc surface.

[0014] As an optional embodiment, in the first aspect of the present invention, the number of blades is 6-9, and the blades are circumferentially evenly spaced.

[0015] A second aspect of the present invention provides a centrifugal booster pump, comprising: a pump body, a main shaft, a rear cover and the above-mentioned impeller, the rear cover is fixed at the axial rear end of the pump body to form an axially through structure, the rear cover is provided with an oil suction port, a vortex chamber is provided in the pump body, an oil discharge port is provided in the pump body corresponding to the vortex chamber, the impeller is provided in the vortex chamber, the main shaft is axially provided in the pump body, and the main shaft is drivingly connected to the impeller.

[0016] As an optional embodiment, in the second aspect of the present invention, the axis of the bottom plate of the impeller protrudes outwardly away from the axial direction of the cover plate to form a connecting portion, the main shaft passes through the connecting portion, and the connecting portion and the main shaft are transmission-connected by a matching spline structure.

[0017] As an optional embodiment, in the second aspect of the present invention, the cover plate protrudes axially away from the base plate to form a boss, the boss is arranged on the radial outer periphery of the oil inlet, and a second oil seal is provided between the outer periphery of the boss and the inner wall of the pump body, and a first oil seal is provided between the side wall of the main shaft and the inner wall of the front end of the pump body.

[0018] As an optional embodiment, in the second aspect of the present invention, a first retaining ring is provided between the front end of the first oil seal and the pump body, a third retaining ring is provided between the rear end of the second oil seal and the pump body, and a second retaining ring is provided at the end where the impeller is connected to the main shaft.

[0019] As an optional embodiment, in the second aspect of the present invention, the main shaft passes through the impeller, the front interference sleeve of the main shaft is provided with a first bearing, the rear interference sleeve of the main shaft is provided with a second bearing supported by the bearing seat, and the oil suction port is connected to the impeller through the bearing seat.

[0020] As an optional embodiment, in the second aspect of the present invention, the front end of the main shaft is used to connect to the output shaft of the motor, and the main shaft and the output shaft of the motor are connected via a flat key transmission.

[0021] As an optional implementation, in the second aspect of the present invention, an O-ring is provided between the rear cover and the pump body, and the rear cover and the pump body are fixedly connected by bolts.

[0022] The impeller and centrifugal booster pump provided by the present invention have the following beneficial effects:

[0023] The radial extension line of the projection of the impeller blade on the base plate satisfies the exponential function y = ae bx The change law of a is 1.35-1.95, and the value of b is 0.13-0.16, so that the blades extend radially inward from the circumferential edge of the impeller in an arc shape, and the spacing between adjacent blades close to the circumferential edge of the impeller is greater than the spacing close to the axis of the impeller. In this way, the impeller is applied to the centrifugal booster pump. After the centrifugal booster pump absorbs oil, the high-speed rotation of the impeller can drive several blades to rotate synchronously, so that the hydraulic oil is thrown from the center of the impeller to the circumferential edge by centrifugal force, and flows out from the oil discharge port at a higher pressure for the hydraulic pump to absorb oil. At the same time, a certain vacuum is formed at the center of the impeller due to the hydraulic oil being thrown out, so that the hydraulic oil can enter the centrifugal booster pump through the oil suction port due to the pressure difference, and enter the impeller through the oil inlet. In this way, the impeller rotates continuously, so that the hydraulic oil is continuously sucked in and discharged, thereby improving the boosting effect and oil delivery efficiency of the centrifugal booster pump on the basis of ensuring the quality of the hydraulic oil, so as to meet the oil suction demand of the hydraulic pump, and has the characteristics of simple structure and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the impeller of Example 1;

[0025] Figure 2 It is a front view of the impeller of Example 1;

[0026] Figure 3 is a top view of the impeller of Example 1;

[0027] Figure 4 is an exponential function diagram of the radial extension line of the blade of Example 1;

[0028] Figure 5 It is a structural schematic diagram of the centrifugal booster pump of Example 2;

[0029] Figure 6 is an axial cross-sectional view of the centrifugal booster pump of Example 2;

[0030] Figure 7 It is a schematic structural diagram of the pump body of Example 2;

[0031] Figure 8 This is a cross-sectional view of the vortex chamber of the pump body of Example 2.

[0032] The meanings of the reference numerals are as follows:

[0033] 1. Pump body; 101. Vortex chamber; 102. Oil discharge port; 2. Main shaft; 3. Flat key; 4. First retaining ring; 5. First oil seal; 6. First bearing; 7. Second retaining ring; 8. Impeller; 81. Cover plate; 811. Oil inlet; 82. Bottom plate; 83. Blade; 831. First surface; 832. Second surface; 833. Transition surface; 84. Oil outlet; 85. Connecting part; 851. Spline structure; 86. Boss; 9. Second oil seal; 10. Third retaining ring; 11. Rear cover; 111. Oil suction port; 12. Bolt; 13. O-ring; 14. Bearing seat; 15. Second bearing. DETAILED DESCRIPTION

[0034] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0035] In the description of the present invention, it should be noted that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0037] Example 1

[0038] See also Figure 1-4 The present embodiment provides an impeller, comprising: a cover plate 81, a bottom plate 82 and a plurality of blades 83. The cover plate 81 is provided with an oil inlet 811, and the bottom plate 82 and the cover plate 81 are arranged at intervals to form a cylindrical structure. The plurality of blades 83 are connected between the cover plate 81 and the bottom plate 82, and adjacent blades 83 are arranged at intervals to form an oil outlet 84, and the radial extension line of the projection of the blade 83 on the bottom plate 82 satisfies the exponential function y=ae bx The changing law of a is 1.35-1.95, and the value of b is 0.13-0.16.

[0039] The cover plate 81 and the bottom plate 82 are two circular plates arranged opposite to each other and adapted to each other. The cover plate 81 and the bottom plate 82 are arranged opposite to each other so that the cover plate 81, the bottom plate 82 and the area therebetween form a cylindrical structure, so as to facilitate the rotation of the impeller 8 around the circular axis. The opposite ends of a plurality of blades 83 are respectively connected to the cover plate 81 and the bottom plate 82. The plurality of blades 83 are arranged at intervals and extend from the circumferential edge of the impeller 8 in the radial direction close to the axis of the impeller 8 to form a chamber in the center of the impeller 8.

[0040] On this basis, the radial extension line of the projection of the blade 83 of the impeller 8 on the bottom plate 82 satisfies the exponential function y=ae bx The change rule of a is 1.35-1.95, and the value of b is 0.13-0.16, so that the blades 83 extend radially inward from the circumferential edge of the impeller 8 in an arc shape, and the spacing between adjacent blades 83 close to the circumferential edge of the impeller 8 is greater than the spacing close to the axis of the impeller 8, that is, the thickness of the blades 83 gradually decreases from the circumferential edge to the inside. In this way, when the impeller 8 rotates, the blades 83 are driven to rotate synchronously, so that the hydraulic oil is thrown from the center of the impeller 8 to the circumferential edge by centrifugal force, so that the hydraulic oil flows out from the oil outlet 84. At the same time, the central chamber of the impeller 8 forms a certain vacuum due to the hydraulic oil being thrown out, so that the hydraulic oil can enter the impeller 8 through the oil inlet 811 due to the pressure difference. In this way, the impeller 8 rotates continuously, so that the hydraulic oil is continuously sucked in and discharged, thereby improving the boosting effect and oil delivery efficiency on the basis of ensuring the quality of the hydraulic oil.

[0041] See also Figure 3 and Figure 4 The blade 83 includes a first surface 831 and a second surface 832 which are circumferentially spaced apart. The first surface 831 and the second surface 832 both extend radially, and the projections of the first surface 831 and the second surface 832 on the bottom plate 82 both satisfy the exponential function y=ae. bx The change rule of a is 1.35-1.95, and the value of b is 0.13-0.16. In this way, the first surface 831 and the second surface 832 are spaced apart and both extend radially inward from the circumferential edge of the impeller 8 in an arc shape, and according to the change rule of the exponential function curve, the spacing between the first surface 831 and the second surface 832 gradually decreases from the axial edge inward, that is, the thickness of the blade 83 gradually decreases from the circumferential edge inward, which is conducive to the formation of a vortex in the central chamber of the impeller 8 when a number of blades 83 rotate, which is convenient for using centrifugal force to discharge the hydraulic oil, and can form a certain vacuum in the central chamber of the impeller 8 when discharging the hydraulic oil, so as to use the pressure difference to suck in the hydraulic oil. In this way, the impeller 8 can continuously inhale and discharge the hydraulic oil, so as to achieve the purpose of efficient pressurization and oil transportation.

[0042] The distance between the corresponding positions of the first surface 831 and the second surface 832 is the thickness d of the blade 83, the diameter of the circular structure surrounded by the blades 83 is the diameter D of the impeller 8, and the ratio of D / d satisfies 5-10:1. Preferably, the ratio of D / d is 7:1. In this way, on the basis of ensuring the centrifugal force and pressure difference brought by the rotation of the blades 83, the hydraulic oil can be smoothly sucked in and discharged, thereby increasing the effective output flow of the hydraulic oil, so as to achieve the purpose of efficient oil delivery.

[0043] The number of blades 83 is 6-9, and the blades 83 are evenly spaced in the circumferential direction. In this way, the blades 83 are arranged in the impeller 8, and the spacing between adjacent blades 83 can effectively balance the centrifugal force, pressure difference and oil discharge, thereby efficiently increasing pressure and delivering oil.

[0044] In addition, the ends of the first surface 831 and the second surface 832 close to the axis of the impeller 8 are connected by a transition surface 833, and the transition surface 833 is an arc surface. The transition surface 833 is an arc surface, which can prevent the hydraulic oil from being sheared at high speed when the blades 83 rotate at high speed, thereby preventing the hydraulic oil from being "torn" and deteriorating, thereby ensuring the effective output flow of the hydraulic oil and improving the oil delivery efficiency.

[0045] In addition, see Figure 1-3 The axis of the bottom plate 82 of the impeller 8 is axially protruded away from the cover plate 81 to form a connecting portion 85, and the connecting portion 85 is used for transmission connection with the pump shaft. Specifically, the connecting portion 85 is sleeved on the pump shaft, and the connecting portion 85 and the pump shaft are correspondingly provided with a matching spline structure 851, so that the transmission between the pump shaft and the impeller 8 is realized through the spline structure 851, so that when the motor drives the pump shaft to rotate, the impeller 8 is driven to rotate synchronously to realize the suction and discharge of hydraulic oil.

[0046] The cover plate 81 axially protrudes away from the bottom plate 82 to form a boss 86, which is arranged at the radial periphery of the oil inlet 811. The boss 86 has a flow-guiding function, so that the hydraulic oil flows along the boss 86 through the oil inlet 811 into the central chamber of the impeller 8, thereby improving the smoothness of the hydraulic oil suction.

[0047] Example 2

[0048] See also Figure 5-8 The present embodiment provides a centrifugal booster pump, comprising: a pump body 1, a main shaft 2, a rear cover 11 and the impeller 8 of embodiment 1, the rear cover 11 is fixed at the axial rear end of the pump body 1 to form an axially through structure, the rear cover 11 is provided with an oil suction port 111, a vortex chamber 101 is provided in the pump body 1, an oil discharge port 102 is provided in the pump body 1 corresponding to the vortex chamber 101, the impeller 8 is arranged in the vortex chamber 101, the main shaft 2 is axially arranged in the pump body 1, and the main shaft 2 is transmission-connected to the impeller 8.

[0049] The vortex chamber 101 is arranged in the pump body 1 and communicated with the oil discharge port 102, and the center of the vortex chamber 101 coincides with the axis of the pump body 1. The vortex chamber 101 is a volute-shaped structure, and the flow channel in the vortex chamber 101 becomes larger as it approaches the oil discharge port 102, so that the high-speed hydraulic oil thrown out by the impeller 8 reduces the flow rate, converts part of the kinetic energy into static pressure energy, and then is discharged from the oil discharge port 102. The impeller 8 is arranged in the vortex chamber 101, and the main shaft 2 axially penetrates the impeller 8 to be in transmission connection with the impeller 8.

[0050] In this way, the rotation of the main shaft 2 drives the impeller 8 and the blades 83 to rotate synchronously to make the centrifugal booster pump absorb oil, and the hydraulic oil enters the central chamber of the impeller 8 through the oil suction port 111 and the oil inlet 811 in turn, so that the hydraulic oil can be thrown from the center of the impeller 8 to the circumferential edge by centrifugal force, so that the hydraulic oil flows out from the oil outlet 84 into the vortex chamber 101, and flows out through the oil discharge port 102 at a higher pressure for the hydraulic pump to absorb oil. At the same time, the central chamber of the impeller 8 forms a certain vacuum due to the hydraulic oil being thrown out, so that the hydraulic oil can enter the impeller 8 through the oil suction port 111 and the oil inlet 811 in turn due to the pressure difference. In this way, the impeller 8 rotates continuously, so that the hydraulic oil is continuously sucked in and discharged, thereby improving the boosting effect and oil delivery efficiency of the centrifugal booster pump on the basis of ensuring the quality of the hydraulic oil, so as to meet the oil suction demand of the hydraulic pump, and has the characteristics of simple structure and low cost.

[0051] The axis of the bottom plate 82 of the impeller 8 is axially protruded away from the cover plate 81 to form a connecting portion 85, the main shaft 2 passes through the connecting portion 85, and the connecting portion 85 is transmission-connected with the main shaft 2 through a matching spline structure 851. The connecting portion 85 is sleeved on the main shaft 2, and the connecting portion 85 and the main shaft 2 are correspondingly provided with a matching spline structure 851, so as to realize the transmission connection between the main shaft 2 and the impeller 8 through the spline structure 851, so that when the motor drives the main shaft 2 to rotate, the impeller 8 is driven to rotate synchronously, so as to realize the suction and discharge of hydraulic oil.

[0052] The cover plate 81 protrudes axially outward away from the bottom plate 82 to form a boss 86, which is arranged on the radial outer periphery of the oil inlet 811, and a second oil seal 9 is provided between the outer periphery of the boss 86 and the inner wall of the pump body 1, and a first oil seal 5 is provided between the side wall of the main shaft 2 and the inner wall of the front end of the pump body 1.

[0053] The boss 86 has a flow-guiding function, so that the hydraulic oil flows into the central chamber of the impeller 8 through the oil inlet 811 along the boss 86, thereby improving the smoothness of the hydraulic oil suction. The first oil seal 5 can prevent the hydraulic oil from leaking from the front end of the main shaft 2 along the connection between the main shaft 2 and the connecting part 85, and the second oil seal 9 can prevent the hydraulic oil from flowing back to the oil suction port 111 after being thrown out by the impeller 8. In this way, the first oil seal 5 and the second oil seal 9 can cooperate to prevent the front and rear leakage of the hydraulic oil, so as to ensure that the hydraulic oil is discharged to the hydraulic pump through the oil discharge port 102 according to the established route, thereby improving the solvent efficiency of the centrifugal booster pump.

[0054] Furthermore, a first retaining ring 4 is provided between the front end of the first oil seal 5 and the pump body 1 , a third retaining ring 10 is provided between the rear end of the second oil seal 9 and the pump body 1 , and a second retaining ring 7 is provided at the end of the impeller 8 which is transmission-connected to the main shaft 2 .

[0055] The first retaining ring 4 is used to axially fix the first oil seal 5, thereby ensuring the sealing performance of the first oil seal 5. The third retaining ring 10 is used to axially fix the second oil seal 9, thereby ensuring the sealing performance of the second oil seal 9. The second retaining ring 7 is provided at both ends of the connecting portion 85, thereby further preventing the hydraulic oil from leaking toward the front end of the main shaft 2 on the basis of ensuring the reliability of the transmission connection between the main shaft 2 and the connecting portion 85.

[0056] The main shaft 2 passes through the impeller 8, the front end interference sleeve of the main shaft 2 is provided with a first bearing 6, the rear end interference sleeve of the main shaft 2 is provided with a second bearing 15 supported by a bearing seat 14, and the oil suction port 111 is connected with the impeller 8 through the bearing seat 14. The coordinated use of the main shaft 2, the first bearing 6 and the second bearing 15 is conducive to improving the smoothness of the rotation of the main shaft 2, thereby improving the rotation efficiency of the impeller 8, so as to efficiently transport oil.

[0057] The front end of the main shaft 2 is used to connect the output shaft of the motor, and the main shaft 2 and the output shaft of the motor are connected by a flat key 3. The motor is used to drive the main shaft 2 to rotate. The setting of the flat key 3 is conducive to improving the reliability of the rotation connection between the motor and the main shaft 2, thereby improving the service life of the centrifugal booster pump.

[0058] In addition, an O-ring 13 is provided between the rear cover 11 and the pump body 1, and the rear cover 11 and the pump body 1 are fixedly connected by bolts 12. The rear cover 11 and the pump body 1 are firmly connected, and the O-ring 13 is conducive to improving the sealing of the connection between the rear cover 11 and the pump body 1 to avoid oil leakage.

[0059] The technical means disclosed in the scheme of the present invention are not limited to the technical means disclosed in the above-mentioned implementation mode, but also include technical schemes composed of any combination of the above-mentioned technical features. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also regarded as the protection scope of the present invention.

Claims

1. An impeller, characterized in that: include: A cover plate, wherein an oil inlet is provided on the cover plate; A bottom plate, wherein the bottom plate and the cover plate are spaced and arranged correspondingly to form a cylindrical structure; A plurality of blades, wherein the plurality of blades are connected between the cover plate and the bottom plate, and adjacent blades are spaced apart to form an oil outlet; The radial extension line of the projection of the blade on the base plate satisfies the exponential function y=ae bx The changing law of a is 1.35-1.95, and the value of b is 0.13-0.

16.

2. The impeller according to claim 1, characterized in that: The blade comprises a first surface and a second surface arranged circumferentially at intervals, the first surface and the second surface both extend radially, and the projections of the first surface and the second surface on the bottom plate both satisfy the exponential function y=ae bx The changing law of a is 1.35-1.95, and the value of b is 0.13-0.

16.

3. The impeller according to claim 2, characterized in that: The distance between the corresponding positions of the first surface and the second surface is the thickness d of the blade, the diameter of the circular structure surrounded by a plurality of the blades is the diameter D of the impeller, and the ratio of D / d satisfies (5-10):

1.

4. The impeller according to claim 2, characterized in that: The ends of the first surface and the second surface close to the impeller axis are connected by a transition surface, and the transition surface is an arc surface.

5. The impeller according to claim 1, characterized in that: The number of the blades is 6-9, and the blades are circumferentially distributed with equal intervals.

6. A centrifugal booster pump, characterized in that: include: A pump body, a main shaft, a rear cover and an impeller as described in any one of claims 1 to 5, wherein the rear cover is fixed to the axial rear end of the pump body to form an axially through structure, the rear cover is provided with an oil suction port, a vortex chamber is provided in the pump body, an oil discharge port is provided in the pump body corresponding to the vortex chamber, the impeller is provided in the vortex chamber, the main shaft is axially provided in the pump body, and the main shaft is drivingly connected to the impeller.

7. The centrifugal booster pump according to claim 6, characterized in that: The axis of the bottom plate of the impeller is axially protruded outward away from the cover plate to form a connecting portion, the main shaft passes through the connecting portion, and the connecting portion and the main shaft are transmission-connected via a matching spline structure.

8. The centrifugal booster pump according to claim 6, characterized in that: The cover plate protrudes axially outward away from the base plate to form a boss, the boss is arranged at the radial outer periphery of the oil inlet, and a second oil seal is provided between the outer periphery of the boss and the inner wall of the pump body, and a first oil seal is provided between the side wall of the main shaft and the inner wall of the front end of the pump body.

9. The centrifugal booster pump according to claim 8, characterized in that: A first retaining ring is provided between the front end of the first oil seal and the pump body, a third retaining ring is provided between the rear end of the second oil seal and the pump body, and a second retaining ring is provided at the end of the impeller that is transmission-connected to the main shaft.

10. The centrifugal booster pump according to claim 6, characterized in that: The main shaft passes through the impeller, the front interference sleeve of the main shaft is provided with a first bearing, the rear interference sleeve of the main shaft is provided with a second bearing supported by a bearing seat, and the oil suction port is connected with the impeller through the bearing seat.

11. The centrifugal booster pump according to claim 6, characterized in that: The front end of the main shaft is used to connect with the output shaft of the motor, and the main shaft and the output shaft of the motor are connected through a flat key transmission.

12. The centrifugal booster pump according to claim 6, characterized in that: An O-ring is arranged between the rear cover and the pump body, and the rear cover and the pump body are fixedly connected by bolts.

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