Axial shaftless rim propeller based on water-cooling heat dissipation structure

Abstract

The invention discloses an axial shaftless rim propeller based on a water-cooling heat dissipation structure. The axial shaftless rim propeller comprises two stators, a rotor, a bearing and a machine shell. Wherein the bearings comprise two water-lubricated thrust bearings and a water-lubricated radial bearing. The two stators are located on the two sides of the rotor respectively, the water lubrication radial bearing is arranged between the rotor and the machine shell, and the two water lubrication thrust bearings are arranged between the two stators and the rotor respectively. The stators on the two sides are of a three-dimensional integrated water-cooling heat dissipation structure, and the rotor is of a clearance water-cooling heat dissipation structure. During working, water flow can flow in from the heat dissipation structure of the stator on one side and flow out from the heat dissipation structure of the stator on the other side after passing through the heat dissipation structure of the rotor, so that heat generated during working of the stator and the rotor is taken away, and heat accumulation is avoided. The high power density of the motor is guaranteed by improving the thermal stability, and meanwhile, the running stability and safety of the motor are also improved.

Description

Technical Field

[0001] The present invention relates to a ship propulsion structure, and particularly to a shaftless rim propeller. Background Art

[0002] Traditional ship propulsion devices adopt a combination of a propulsion shaft system and a propeller. The propeller is connected to a shaft, and the shaft extends from the stern to the prime mover inside the ship's hull. This design exposes the shaft outdoors for a long time, occupies a large amount of space, resulting in large frictional losses, an increase in the ship's volume, and an increase in construction costs. At the same time, there are also problems of noise and vibration, reducing the propulsion efficiency and reliability.

[0003] As a new type of ship propulsion method, the shaftless rim propeller integrates the motor and the propeller, reduces the cabin space occupied by the propulsion system, improves the space utilization rate, increases the ship's propulsion efficiency, reduces vibration and noise, and ensures the concealment of the ship. However, when the shaftless propeller is working, due to the close integration of the stator and the rotor, a large amount of heat will be generated. These heats mainly come from the heat generated by the stator and rotor of the motor during operation. Due to the compact design of the shaftless propeller, the heat dissipation ability is poor, and the heat is difficult to dissipate in time. The high temperature will cause the motor working efficiency to decrease, and may even affect the safety and service life of the motor.

[0004] As an advanced electric propulsion system, the axial shaftless rim propeller has the advantages of high power density, compact structure, and high efficiency. An axial-flux shaftless rim propeller of CN119253962A discloses an axial-flux shaftless rim propeller, including a housing, a rotor, and two annular stators. The rotor is located inside the housing, and the rotor and the housing are connected by a water-lubricated radial bearing. The two annular stators are respectively arranged on both sides of the rotor, and water-lubricated thrust bearings are respectively arranged between the annular stator and the rotor. This shaftless rim propeller reduces the axial dimension, balances the axial magnetic pull force. Compared with the radial-flux shaftless rim propeller, it can provide a larger torque output under the same volume, improving the output power of the motor. In addition, the shaftless motor structure reduces the axial dimension of the ship propeller, provides sufficient space for the arrangement of the thrust bearing, significantly reduces friction and wear, reduces noise, effectively improves the performance of the motor, extends the service life of the motor, and further improves the running stability and efficiency of the motor. However, since its permanent magnets and windings are both on the stator, the stator sheath increases the eddy current loss, exacerbating the heat generation problem of this shaftless rim propeller, and ultimately making the motor efficiency lower than the design target. Summary of the Invention

[0005] Object of the Invention: Aiming at the above-mentioned prior art, an axial shaftless rim propeller based on a water-cooling heat dissipation structure is proposed to improve the heat dissipation efficiency of the stator and the rotor.

[0006] Technical solution: An axial shaftless rim propeller based on a water-cooled heat dissipation structure, comprising two stators, a rotor, bearings and a housing; wherein the bearings include two water-lubricated thrust bearings and a water-lubricated radial bearing; the two stators are respectively located on both sides of the rotor, the water-lubricated radial bearing is arranged between the rotor and the housing, and the two water-lubricated thrust bearings are respectively arranged between the two stators and the rotor; a plurality of propeller blades are installed on the inner ring of the rotor yoke of the rotor, and the outer side of the rotor is covered with a waterproof shell; the stators on both sides adopt a three-dimensional integrated water-cooled heat dissipation structure, and the rotor adopts an interstitial water-cooled heat dissipation structure. The cooling water flow can flow into from the heat dissipation structure of one side stator, flow through the heat dissipation structure of the rotor, and then flow out of the axial shaftless rim propeller after flowing into the heat dissipation structure of the other side stator.

[0007] Further, the stator includes a housing for accommodating a stator core, a permanent magnet and an armature winding; the three-dimensional integrated water-cooled heat dissipation structure includes a stator water-cooled heat dissipation channel located inside the outer side surface of the housing. One channel port of one end of the stator water-cooled heat dissipation channel is located on the end surface of the housing adjacent to the water-lubricated thrust bearing, and the other channel port of the other end of the stator water-cooled heat dissipation channel is located on the outer side surface of the housing.

[0008] Further, the stator water-cooled heat dissipation pipeline includes three parts, namely a spiral pipeline section distributed along the outer circumference side of the annular stator, a plurality of radial pipeline sections and a plurality of circumferential pipeline sections inside the outer side end surface of the housing; each radial pipeline section and circumferential pipeline section are alternately connected in series to form a passage. One end of the passage is connected to one end of the spiral pipeline section, the other end of the spiral pipeline section is connected to the channel port one, and the other end of the passage is connected to the channel port two.

[0009] Further, the zigzag unit structure formed by connecting the radial pipeline section and the circumferential pipeline section is directly opposite to the high-temperature area during the operation of the permanent magnet and the armature winding.

[0010] Further, the housing includes a stator lower end cover and a stator upper end cover assembled outside the stator lower end cover; semi-circular grooves of the stator water-cooled heat dissipation channel are respectively machined on the opposite surfaces of the stator upper end cover and the stator lower end cover, and the opposite semi-circular grooves form a complete channel when the stator lower end cover and the stator upper end cover are assembled.

[0011] Further, the interstitial water-cooled heat dissipation structure includes the gaps between the water-lubricated thrust bearings on both sides of the rotor and the relative stators, the water-lubricated radial bearing, and the water flow path formed by the paths along the central axis between the water-lubricated thrust bearings on both sides.

[0012] Further, each stator includes two independent stator water-cooled heat dissipation pipelines, and each stator water-cooled heat dissipation pipeline is provided with its own independent channel port one and channel port two.

[0013] Beneficial effects: Based on an axial magnetic flux shaftless rim propeller, the present invention designs a stator and rotor water-cooling heat dissipation structure to solve the heat dissipation problem of the stator and rotor. For the propulsion motor structure with both permanent magnet and electric excitation on the stator, a three-dimensional water-cooling heat dissipation structure is cooperatively arranged through the stator end cover to increase the heat dissipation efficiency of the stator and reduce the risk of permanent magnet demagnetization.

[0014] Two independent cooling circuits are designed on each stator, which can reduce the resistance of water flow, increase the flow rate, and thus improve the heat dissipation efficiency.

[0015] The heat dissipation path of the rotor gap water cooling structure is in a "convex" shape, which is conducive to increasing the pressure difference and improving the water gap flow rate. The water flow fully contacts the heated rotor during the flow process, quickly absorbs and takes away the heat of the rotor, and can achieve continuous heat dissipation of the rotor, ensuring that the rotor runs stably at an appropriate temperature.

[0016] The coordinated work of the three-dimensional water-cooling heat dissipation structure of the stator end cover and the gap water-cooling heat dissipation structure of the rotor can prevent heat from accumulating in the shaftless rim thruster, and the high power density of the motor is guaranteed by improving thermal stability, while also improving the operating stability and safety of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the axial shaftless rim propeller of the present invention; Figure 2 is an exploded view of the axial shaftless rim propeller of the present invention; Figure 3 It is an exploded view of the stator structure of the axial shaftless rim propeller of the present invention; Figure 4 It is a flow diagram of the three-dimensional integrated water-cooling heat dissipation structure of the stator end cover in the structure of the present invention, wherein (a) is the three-dimensional structure of the stator lower end cover Figure 1 , (b) is the three-dimensional structure of the stator lower end cover Figure 2 , (c) is a three-dimensional structural diagram of the stator upper end cover; Figure 5 It is a flow diagram of the gap water cooling heat dissipation structure of the rotor in the structure of the present invention. DETAILED DESCRIPTION

[0018] The present invention will be further explained below in conjunction with the accompanying drawings.

[0019] like Figure 1 , Figure 2As shown in the figure, an axial shaftless rim propeller based on a water-cooled heat dissipation structure includes two stators 1, a rotor 2, bearings, and a housing 3. The bearings include two water-lubricated thrust bearings 4 and a water-lubricated radial bearing 5. The two stators 1 are respectively located on both sides of the rotor 2, the water-lubricated radial bearing 5 is arranged between the rotor 2 and the housing 3, and the two water-lubricated thrust bearings 4 are respectively arranged between the two stators 1 and the rotor 2. The water-lubricated thrust bearing 4 and the water-lubricated radial bearing 5 are respectively used to restrict the axial and radial movements of the rotor 2. A number of propeller blades 25 are installed on the inner ring of the rotor yoke 22 of the rotor 2, and fourteen rotor teeth 21 are fixedly connected to the outer circumference of the rotor yoke 22. The outside of the rotor 2 is covered with a waterproof shell 23, which completely covers the rotor teeth 21, and the remaining gaps inside the waterproof shell 23 are filled with a lightweight heat-conducting material. A ship connector is provided on the outside of the housing 3 for connecting the propeller to the ship.

[0020] In the above structure, the stators on both sides adopt a three-dimensional integrated water-cooled heat dissipation structure, and the rotor adopts an interstitial water-cooled heat dissipation structure.

[0021] Specifically, as Figures 2 to 4 shown, the stator 1 includes a sealing ring 11, an E-shaped stator core 12, a permanent magnet 13, an armature winding 14, an upper stator cover 15, and a lower stator cover 16. Among them, the lower stator cover 16 is an inwardly concave circular ring structure, and six stator slot wedges are arranged at intervals along the circumferential direction inside the lower stator cover 16, and an E-shaped stator core 12 is embedded between adjacent stator slot wedges. Each permanent magnet 13 is installed on the stator slot wedge, and the magnetization directions of two adjacent permanent magnets 13 are opposite, and the top of the permanent magnet 13 is flush with the top of the E-shaped stator core 12. The armature winding 14 is wound around the E-shaped stator core 12 and the permanent magnet 13. The circular sealing ring 11 covers the lower stator cover 16, sealing the E-shaped stator core 12, the permanent magnet 13, and the armature winding 14 inside the lower stator cover 16. The upper stator cover 15 is assembled outside the lower stator cover 16, and the two are closely fitted. Semi-circular grooves of the stator water-cooled heat dissipation channel 19 are machined on the opposite surfaces of the upper stator cover 15 and the lower stator cover 16, and a complete channel is formed after assembly. The two channel ports of the water-cooled heat dissipation channel 19 are respectively located on the upper stator cover 15 and the lower stator cover 16.

[0022] In this embodiment, as Figure 4As shown in (b) and (c), the stator water-cooling heat dissipation pipeline 19 is composed of three parts, namely: a spiral pipeline section 191 distributed along the outer circumferential side of the stator lower end cover 16, several radial pipeline sections 192 and several circumferential pipeline sections 193 on the opposite end faces of the stator lower end cover 16 and the stator upper end cover 15. Each radial pipeline section 192 and circumferential pipeline section 193 are alternately connected in series to form a passage. The zigzag unit structure formed by the connection of the radial pipeline section 192 and the circumferential pipeline section 193 is directly opposite to the high-temperature areas during the operation of the permanent magnet 13 and the armature winding 14 of the stator. One end of this passage is connected to one end of the spiral pipeline section 191, the other end of the spiral pipeline section 191 is connected to a channel port 17 on the stator lower end cover 16, and the other end of the passage is connected to a channel port 18 on the stator upper end cover 15. Thus, a complete three-dimensional integrated cooperative water-cooling stator water-cooling heat dissipation pipeline is formed. It should be noted that Figure 4 (a) and (b) are perspective views of different angles of the same stator lower end cover.

[0023] In this embodiment, two independent stator water-cooling heat dissipation pipelines 19 are respectively arranged on each stator 1. The channel ports 18 of the two stator water-cooling heat dissipation pipelines 19 located on the stator upper end cover 15 are respectively located at both ends of the diameter of the circular ring-shaped stator upper end cover. The passages on the opposite end faces of the stator lower end cover 16 and the stator upper end cover 15 are respectively located on both sides of a certain diameter of the circular ring-shaped end face, that is, each occupies half of the area of the end face. By setting two independent stator water-cooling heat dissipation pipelines 19, the path length of a single heat dissipation passage is shortened. Compared with using a single longer heat dissipation passage, this solution can effectively reduce the resistance during the water flow, improve the flow rate, and thus improve the heat dissipation efficiency. In addition, the outer side of the stator upper end cover 15 is smoothed to reduce the water resistance.

[0024] The gap water-cooling heat dissipation structure 24 of the rotor refers to the water flow path formed by the gaps between the water-lubricated thrust bearings 4 on both sides of the rotor 2 and the relative stator 1, the water-lubricated radial bearing 5, and the path between the two water-lubricated thrust bearings 4 along the central axis.

[0025] After the axial shaftless rim propeller of the present invention is powered on, the armature winding 14 generates a magnetic field to drive the entire rotor 2 to rotate, so that the propeller blades 25 rotate synchronously, and a pressure difference will be formed on both sides of the blades. Under the action of this pressure difference, water flows in from the channel port 18 of one side stator 1, passes through the stator water-cooled heat dissipation pipe 19, and then flows out from the channel port 17 of this stator 1 to the end face of the same-side water-lubricated thrust bearing 4, and then converges from the gap between the water-lubricated thrust bearing 4 and the seal ring 11 of the stator 1 into the central hole of the bearing, then passes through the propeller blade 25 from the center of the rotor 2, and then flows in from the center of the other water-lubricated thrust bearing 4 through the gap between the bearing and the seal ring 11 of the adjacent stator 1, and then flows radially to the outside along the end face of the water-lubricated thrust bearing 4. At this time, the water flow is divided into two paths. One path flows into the stator water-cooled heat dissipation pipe 19 from the channel port 17 of this side stator 1 and then flows out of the axial shaftless rim propeller from the channel port 18 of this stator 1; the other path is as Figure 5 shown, the water flowing into the water-lubricated radial bearing 5 outside the rotor 2 along the gap, and then flowing into the outer end face of the water-lubricated thrust bearing 4 on this side opposite to the seal ring 11 from the gap on the other side, so as to be mixed with the water flow flowing out from the channel port 17 of the stator water-cooled heat dissipation pipe 19 on this side, and then continue to converge radially into the central hole of the water-lubricated thrust bearing 4 to form a water circulation for water-cooling and heat dissipation in the rotor gap. Among them, on the one hand, the water flow serves as the lubricating medium for the water-lubricated thrust bearing 4 and the water-lubricated radial bearing 5, and on the other hand, it can contact the waterproof shell 23 of the heat-generating rotor 2 during the flowing process, quickly absorb the heat of the rotor 2, and carry the heat out of the axial shaftless rim propeller. As Figure 5 shown, the heat dissipation path of the water-cooling and heat dissipation structure in the rotor gap is in a "convex" shape, which is beneficial to increasing the pressure difference and improving the water flow velocity in the gap.

[0026] The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. An axial shaftless rim propeller based on a water-cooled heat dissipation structure, characterized in that: The invention comprises two stators (1), a rotor (2), a bearing and a casing (3); wherein the bearing comprises two water-lubricated thrust bearings (4) and a water-lubricated radial bearing (5); the two stators (1) are respectively located on both sides of the rotor (2); the water-lubricated radial bearing (5) is arranged between the rotor (2) and the casing (3); and the two water-lubricated thrust bearings (4) are respectively arranged between the two stators (1) and the rotor (2); the inner ring of the rotor yoke (22) of the rotor (2) is provided with a plurality of propeller blades (25); and the outer side of the rotor (2) is covered with a waterproof shell (23); the stators (1) on both sides adopt a three-dimensional integrated water-cooling heat dissipation structure, and the rotor (2) adopts a gap water-cooling heat dissipation structure, and the heat dissipation water flow can flow into the heat dissipation structure of the stator (1) on one side, flow through the heat dissipation structure of the rotor (2), flow into the heat dissipation structure of the stator (1) on the other side, and then flow out of the axial shaftless rim propeller.

2. The axial shaftless rim propeller according to claim 1, characterized in that: The stator (1) comprises a shell that accommodates a stator core (12), a permanent magnet (13), and an armature winding (14); the three-dimensional integrated water-cooling heat dissipation structure comprises a stator water-cooling heat dissipation channel (19) located inside the outer side surface of the shell, a channel port 1 (17) at one end of the stator water-cooling heat dissipation channel (19) is located on the end surface of the shell adjacent to the water-lubricated thrust bearing (4), and a channel port 2 (18) at the other end of the stator water-cooling heat dissipation channel (19) is located on the outer side surface of the shell.

3. The axial shaftless rim propeller according to claim 2, characterized in that: The stator water-cooling heat dissipation pipeline (19) comprises three parts, namely a spiral pipeline segment (191) distributed along the outer circumference of the annular stator (1), a plurality of radial pipeline segments (192) and a plurality of circumferential pipeline segments (193) within the outer end surface of the shell; the radial pipeline segments (192) and the circumferential pipeline segments (193) are alternately connected in sections to form a passage, one end of the passage is connected to one end of the spiral pipeline segment (191), the other end of the spiral pipeline segment (191) is connected to the channel port one (17), and the other end of the passage is connected to the channel port two (18).

4. The axial rimless propeller according to claim 3, characterized in that: The "X"-shaped unit structure formed by connecting the radial pipeline segment (192) and the circumferential pipeline segment (193) is directly opposite to the high-heat zone of the permanent magnet (13) and the armature winding (14) when they are working.

5. The axial rimless propeller according to claim 4, characterized in that: The housing comprises a stator lower end cover (16) and a stator upper end cover (15) mounted on the outside of the stator lower end cover (16); semicircular grooves of the stator water-cooling heat dissipation channel (19) are respectively processed on the opposite surfaces of the stator upper end cover (15) and the stator lower end cover (16); the opposite semicircular grooves are combined to form a completed channel when the stator lower end cover (16) and the stator upper end cover (15) are assembled.

6. The axial rimless propeller according to any one of claims 2 to 5, characterized in that: The gap water-cooling heat dissipation structure comprises a gap between the water-lubricated thrust bearings (4) on both sides of the rotor (2) and the relative stator (1), a water-lubricated radial bearing (5), and a water flow path formed by a path between the water-lubricated thrust bearings (4) on both sides along the central axis.

7. The axial rimless propeller according to claim 6, characterized in that: Each stator (1) comprises two independent stator water-cooling heat dissipation pipes (19), and each stator water-cooling heat dissipation pipe (19) is provided with a respective independent channel port one (17) and channel port two (18).

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