Underwater shaftless propeller
By designing various sliding bearing structures and sealants, the sealing problem of underwater shaftless thrusters in complex underwater environments was solved, resulting in a longer service life and greater thrust.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- OCEAN INTELLIGENCE (JIANGSU) TECH IND CO LTD
- Filing Date
- 2023-06-28
- Publication Date
- 2026-05-01
AI Technical Summary
In complex underwater environments, the stator windings and magnet assembly of underwater shaftless thrusters are easily worn down by mud and sand, affecting their service life, and are also susceptible to entanglement by aquatic plants.
Various sliding bearing structures and sealants were designed. By increasing the path direction of the fitting clearance, mud and sand were prevented from entering the stator windings and magnet assembly. Combined with traditional rolling bearings and sealants, the protection was enhanced.
It effectively prevents mud and sand from entering, improves the sealing of the stator winding and magnet assembly, extends service life, and enhances the thrust of the propeller and its ability to prevent grass entanglement.
Smart Images
Figure CN121947727A_ABST
Abstract
Description
underwater shaftless thruster Technical Field
[0001] This invention relates to an underwater propulsion device, and more particularly to an underwater shaftless propulsion device. Background Technology
[0002] An underwater shaftless propulsion system, also known as a rim propulsion system, has blades mounted on a rotor instead of a central hub. This effectively prevents underwater debris such as weeds and plastic bags from entangleing and ensures efficient propulsion.
[0003] When designing underwater shaftless thrusters, issues such as waterproofing, noise, and cooling need to be considered. Since the driving principle of underwater shaftless thrusters is based on electromagnetic induction, waterproofing is a key factor determining their lifespan when they are powered on.
[0004] When designing underwater shaftless thrusters, people often use vacuum potting to seal the stator windings and magnet assembly to ensure the thruster is waterproof, thus effectively isolating them from water.
[0005] However, the actual operating conditions of underwater shaftless thrusters are quite complex. During practical use, the applicant discovered that one cause of thruster damage was the destruction of the stator winding's waterproof layer. The applicant's research revealed that although traditional shaftless thrusters undergo encapsulation, the complex underwater environment allows fine sediment to enter between the stator windings and the magnet assembly from the rotating joints. As the rotor rotates, this sediment wears down and damages the encapsulation layer, thus affecting the service life of the underwater shaftless thruster. Summary of the Invention
[0006] The purpose of this invention is to provide an underwater shaftless thruster that can effectively prevent mud and sand from entering the interior, thereby avoiding damage to the stator windings and magnet assembly and greatly improving service life; at the same time, this underwater shaftless thruster can avoid entanglement with aquatic plants and can also withstand greater thrust.
[0007] The technical solution for achieving the objective of this invention is as follows: This invention comprises a stator assembly, a rotor assembly, and a blade assembly; the stator assembly includes a tubular housing with stator windings fixedly disposed on its inner wall; the rotor assembly includes a tubular rotor body with magnet assemblies fixedly disposed on its outer wall; the stator windings and magnet assemblies are sealed with potting compound; a blade assembly is fixedly disposed on the inner wall of the rotor body; the housing is disposed outside the rotor body, and the stator windings and magnet assemblies are both located between the housing and the rotor body; both ends of the rotor body are rotatably connected to the housing via a first bearing assembly and a second bearing assembly, respectively; the fit clearance between the first bearing assembly and the second bearing assembly and the stator windings or magnet assemblies has multiple varying paths.
[0008] Furthermore, the aforementioned first bearing assembly includes a first encapsulation ring, a first sliding ring, and a first sliding sleeve; the first encapsulation ring includes an integrally connected connecting ring portion and an encapsulation ring portion; the encapsulation ring portion extends toward the rotor assembly; the connecting ring portion is fixedly connected to one end of the stator assembly; the first sliding sleeve is fixedly fitted onto the outer wall of one end of the rotor body; the first sliding sleeve is provided with a first limiting ring portion extending toward the stator assembly; a first sliding cavity is formed between the encapsulation ring portion and the first limiting ring portion; the first sliding ring is disposed within the first sliding cavity; the second bearing assembly includes a limiting portion, a second sliding ring, and a second sliding sleeve; the second sliding sleeve is fixedly fitted onto the outer wall of the other end of the rotor body; the first sliding sleeve is provided with a second limiting ring portion extending toward the stator assembly; one end of the housing corresponding to the second sliding sleeve is recessed toward the stator assembly to form a limiting portion; a second sliding cavity is formed between the limiting portion and the second limiting ring portion; the second sliding ring is disposed within the second sliding cavity.
[0009] Furthermore, a partition ring is provided on the first encapsulation ring between the connecting ring portion and the encapsulation ring portion; the partition ring is disposed on the end face of the first encapsulation ring facing the stator winding and its axis extends; the inner and outer sides of the partition ring respectively participate in forming the first sliding cavity and the stator winding mounting cavity; the end face of the partition ring that participates in forming the first sliding cavity is closer to the rotor body than the stator winding.
[0010] As a variation of the design, the first bearing assembly includes a first bearing shell, a second bearing shell, a third slip ring, and a second encapsulating ring. The first and second bearing shells are fixedly mounted on one end of the rotor body after mating. The second encapsulating ring is fixedly connected to the stator assembly. The first and second bearing shells form a third sliding cavity. A fourth sliding cavity is formed between the second encapsulating ring and the stator assembly. The inner and outer ring portions of the third slip ring are slidably disposed within the third and fourth sliding cavities, respectively. The second bearing assembly includes a third bearing shell, a fourth bearing shell, a fourth slip ring, and a limiting groove. The third and fourth bearing shells are fixedly mounted on the other end of the rotor body after mating. The stator assembly at the end corresponding to the fourth bearing shell is recessed inward to form a limiting groove. The third and fourth bearing shells form a fifth sliding cavity. The inner and outer ring portions of the fourth slip ring are slidably disposed within the fifth sliding cavity and the limiting groove, respectively.
[0011] The third and fifth sliding cavities mentioned above are both trapezoidal opening grooves; the inner ring portions of the third and fourth sliding rings are both trapezoidal cross-section ring portions that correspond to and fit with the corresponding trapezoidal opening grooves.
[0012] As a variation of the design, the first bearing assembly includes a first rolling bearing and a press-fit ring; the inner ring of the first rolling bearing is fixedly connected to the rotor body, and the outer ring of the first rolling bearing is press-fitted and fixed to the stator assembly by the press-fit ring; the inner ring portion of the press-fit ring is located above the inner ring of the first rolling bearing; the second bearing assembly includes a second rolling bearing; the inner ring of the second rolling bearing is fixedly connected to the rotating body, and the outer ring of the second rolling bearing mates with the stator assembly; the end of the housing corresponding to the second rolling bearing is recessed to form a cover plate portion; the cover plate portion is fitted under the inner ring of the second rolling bearing.
[0013] Sealant is provided between the aforementioned press-fit ring and the stator assembly, and between the outer ring of the first rolling bearing; sealant is also provided between the cover plate and the outer ring of the second rolling bearing.
[0014] The present invention has positive effects: (1) By increasing the path direction of the fit gap between the first bearing assembly and the second bearing assembly, the present invention can minimize the entry of mud and sand between the stator winding and the magnet assembly, thereby greatly avoiding the wear and damage of the mud and sand on the glue applied to the stator winding and the magnet assembly, and effectively improving the service life.
[0015] (2) In this invention, the first bearing assembly adopts a sliding fit between the first sliding ring and the first sliding cavity, and the second bearing assembly adopts a sliding fit between the second sliding ring and the second sliding cavity. This is equivalent to designing a completely new sliding bearing structure. Furthermore, this structure increases the path direction of the fitting gap, which not only improves the propulsion bearing capacity but also minimizes the entry of mud and sand.
[0016] (3) In this invention, the first bearing assembly is made through the sliding fit of the first bearing shell, the second bearing shell and the third slip ring, and the second bearing assembly is made through the sliding fit of the third bearing shell, the fourth bearing shell and the fourth slip ring. This is equivalent to designing another new sliding bearing structure. Through the fit of the trapezoidal opening groove and the ring part of the trapezoidal section, the fit clearance path direction is increased, which can also prevent the entry of mud and sand.
[0017] (4) The present invention uses the traditional first rolling bearing and second rolling bearing, but the path direction of the fitting clearance is also increased by the press-fit ring and cover plate, which effectively avoids the entry of mud and sand.
[0018] (5) When the present invention uses the traditional first rolling bearing and second rolling bearing, it also uses sealant to further prevent the entry of mud and sand. Attached Figure Description
[0019] To make the content of the present invention easier to understand, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein Figure 1 is a structural schematic diagram of the present invention; Figure 2 is a cross-sectional view of Embodiment 1 of the present invention; Figure 3 is an enlarged schematic diagram of point A in Figure 2; Figure 4 is an installation schematic diagram of the first bearing assembly and the second bearing assembly in Embodiment 2 of the present invention; Figure 5 is an installation schematic diagram of the first bearing assembly and the second bearing assembly in Embodiment 3 of the present invention; Detailed Implementation
[0020] (Example 1) As shown in Figures 1 to 3, the present invention comprises a stator assembly 1, a rotor assembly 2, and a blade assembly 3. The stator assembly 1 includes a tubular housing 12 with stator windings 11 fixed on its inner wall. The rotor assembly 2 includes a tubular rotor body 22 with magnet assemblies 21 fixed on its outer wall. The stator windings 11 and magnet assemblies 21 are sealed with adhesive. The blade assembly 3 is fixed on the inner wall of the rotor body 22. The housing 12 is disposed outside the rotor body 22, and the stator windings 11 and magnet assemblies 21 are both located between the housing 12 and the rotor body 22. The two ends of the rotor body 22 are rotatably connected to the housing 12 via a first bearing assembly 4 and a second bearing assembly 5, respectively. The fitting clearance between the first bearing assembly 4 and the second bearing assembly 5 and the stator windings 11 or magnet assemblies 21 has multiple varying paths. These paths are the paths that sediment must take when it enters. The more directions of the paths, the better the sediment prevention effect.
[0021] The first bearing assembly 4 includes a first encapsulation ring 41, a first sliding ring 42, and a first sliding sleeve 43; the first encapsulation ring 41 includes an integrally connected connecting ring portion 411 and an encapsulation ring portion 412; the encapsulation ring portion 412 extends toward the rotor assembly 2; the connecting ring portion 411 is fixedly connected to one end of the stator assembly 1; the first sliding sleeve 43 is fixedly fitted onto the outer wall of one end of the rotor body 22; the first sliding sleeve 43 is provided with a first limiting ring portion 431 extending toward the stator body assembly 1; a first limiting ring portion 431 is formed between the encapsulation ring portion 412 and the first limiting ring portion 431. A sliding cavity; the first sliding ring 42 is disposed in the first sliding cavity; the second bearing assembly 5 includes a limiting part 51, a second sliding ring 52 and a second sliding sleeve 53; the second sliding sleeve 53 is fixedly fitted on the outer wall of the other end of the rotor body 22; the first sliding sleeve 53 is provided with a second limiting ring part 531 extending towards the stator assembly 1; the housing 12 is recessed into the stator assembly 1 at one end corresponding to the second sliding sleeve 53 to form a limiting part 51; a second sliding cavity is formed between the limiting part 51 and the second limiting ring part 531; the second sliding ring 52 is disposed in the second sliding cavity.
[0022] A partition ring 413 is also provided on the first encapsulation ring 41 between the connecting ring portion 411 and the encapsulation ring portion 412. The partition ring 413 is disposed on the end face of the first encapsulation ring 41 facing the stator winding 11, and its axis extends. The inner and outer sides of the partition ring 413 respectively participate in forming the first sliding cavity and the mounting cavity of the stator winding 11. The end face of the partition ring 413 that participates in forming the first sliding cavity is closer to the rotor body 22 than the stator winding 11. This design allows the stator winding 11 to be better protected by the first encapsulation ring 41, preventing the formation of gaps between the first sliding ring 42 and the second sliding ring 52 and the stator winding 11 that could allow mud and sand to accumulate.
[0023] (Example 2) As shown in Figure 4, the first bearing assembly 4 in this invention includes a first bearing shell 44, a second bearing shell 45, a third slip ring 46, and a second encapsulation ring 47. The first bearing shell 44 and the second bearing shell 45 are fixedly installed at one end of the rotor body 22 after being fitted together. The second encapsulation ring 47 is fixedly connected to the stator assembly 1. The first bearing shell 44 and the second bearing shell 45 cooperate to form a third sliding cavity. A fourth sliding cavity is formed between the second encapsulation ring 47 and the stator assembly 1. The inner ring portion and the outer ring portion of the third slip ring 46 are slidably disposed respectively. Within the third and fourth sliding cavities; the second bearing assembly 5 includes a third bearing shell 54, a fourth bearing shell 55, a fourth slip ring 56, and a limiting groove 57; the third bearing shell 54 and the fourth bearing shell 55 are fixedly installed at the other end of the rotor body 22 after being fitted together; the stator assembly 1 forms the limiting groove 57 by inwardly retracting one end corresponding to the fourth bearing shell 55; the third bearing shell 54 and the fourth bearing shell 55 are fitted together to form a fifth sliding cavity; the inner ring portion and the outer ring portion of the fourth slip ring 56 are slidably disposed within the fifth sliding cavity and the limiting groove, respectively.
[0024] Both the third and fifth sliding cavities are trapezoidal opening grooves; the inner ring portions of the third slip ring 46 and the fourth slip ring 56 are trapezoidal cross-section ring portions that correspond to and cooperate with the corresponding trapezoidal opening grooves.
[0025] Other technical features are the same as in Example 1.
[0026] (Example 3) As shown in Figure 5, in this invention, the first bearing assembly 4 includes a first rolling bearing 48 and a press-fit ring 49; the inner ring of the first rolling bearing 48 is fixedly connected to the rotor body 22, and the outer ring of the first rolling bearing 48 is press-fitted and fixed to the stator assembly 1 by the press-fit ring 49; the inner ring portion of the press-fit ring 49 is located above the inner ring of the first rolling bearing 48; the second bearing assembly 5 includes a second rolling bearing 58; the inner ring of the second rolling bearing 58 is fixedly connected to the rotating body 22, and the outer ring of the second rolling bearing 58 is fitted with the stator assembly 1; the housing 12 is recessed at one end corresponding to the second rolling bearing 58 to form a cover plate portion 121; the cover plate portion 121 is fitted under the inner ring of the second rolling bearing 58.
[0027] Sealant is provided between the press-fit ring 49 and the outer ring of the stator assembly 1 and the first rolling bearing 48; sealant is also provided between the cover plate portion 121 and the outer ring of the second rolling bearing 58.
[0028] Other technical features are the same as in Example 1.
[0029] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. An underwater shaftless thruster, comprising a stator assembly, a rotor assembly, and a blade assembly; characterized in that: The stator assembly includes a tubular housing with stator windings fixed on its inner wall; the rotor assembly includes a tubular rotor body with magnets fixed on its outer wall; the stator windings and magnets are sealed with potting compound; a blade assembly is fixed on the inner wall of the rotor body; the housing is located outside the rotor body, and the stator windings and magnets are both located between the housing and the rotor body; both ends of the rotor body are rotatably connected to the housing via a first bearing assembly and a second bearing assembly, respectively; the fit clearance between the first bearing assembly and the second bearing assembly and the stator windings or magnets has multiple varying paths; the first bearing assembly includes a first bearing bush, a second bearing bush, a third slip ring, and a second sealing ring; the first bearing bush and the second bearing bush are fixed after mating. The first bearing is fixedly installed at one end of the rotor body; the second encapsulation ring is fixedly connected to the stator assembly; the first bearing bush and the second bearing bush cooperate to form a third sliding cavity; a fourth sliding cavity is formed between the second encapsulation ring and the stator assembly; the inner ring and outer ring of the third slip ring are slidably disposed in the third sliding cavity and the fourth sliding cavity, respectively; the second bearing assembly includes a third bearing bush, a fourth bearing bush, a fourth slip ring, and a limiting groove; the third bearing bush and the fourth bearing bush are fixedly installed at the other end of the rotor body after cooperation; the stator assembly at one end corresponding to the fourth bearing bush forms a limiting groove; the third bearing bush and the fourth bearing bush cooperate to form a fifth sliding cavity; the inner ring and outer ring of the fourth slip ring are slidably disposed in the fifth sliding cavity and the limiting groove, respectively.
2. The underwater shaftless thruster according to claim 1, characterized in that: Both the third and fifth sliding cavities are trapezoidal opening grooves; the inner ring portions of the third and fourth sliding rings are trapezoidal cross-section ring portions that correspond to and fit with the corresponding trapezoidal opening grooves.