An underwater propeller
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JINHUA HAIWEI BOAT EQUIP MFG CO LTD
- Filing Date
- 2025-08-04
- Publication Date
- 2026-07-21
Smart Images
Figure CN224528959U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of underwater power equipment technology, and in particular to an underwater propulsion device. Background Technology
[0002] Traditional underwater propulsion devices generally employ parallel-shaft gear transmission schemes, which have significant technical limitations. In terms of spatial layout, the cascading arrangement of multiple gear pairs results in excessively large axial dimensions, increasing the overall size of the propeller and making streamlined shell design difficult. Regarding the transmission system, the successive meshing of gear pairs generates cumulative transmission errors, significantly reducing energy transfer efficiency; actual measurements show that the efficiency of a three-stage transmission is typically less than 85%. More seriously, the impact vibrations during gear meshing are transmitted outwards through the shell, creating underwater noise pollution.
[0003] To address space constraints, existing technologies have attempted to employ helical gears or worm gear structures. While helical gears can improve the single-stage reduction ratio, the addition of axial thrust bearings increases structural complexity. Worm gear structures exhibit reverse self-locking characteristics, which can cause the propeller to rotate uncontrollably when the motor is powered off, posing a safety hazard. Planetary gear transmissions theoretically offer the advantage of compact structure, but in underwater applications, they reveal two key drawbacks: first, the dynamic sealing structure between the planetary carrier's rotating output shaft and the housing struggles to simultaneously meet the dual requirements of high-speed rotation sealing and resistance to deep-water pressure; second, underwater hull deformation under water pressure affects the meshing accuracy of the planetary gear system, making it difficult to maintain the micron-level assembly tolerances of conventional planetary gearboxes in underwater environments.
[0004] The sealing systems of existing propulsion systems also suffer from design contradictions. Parallel shaft structures require multiple bearing support points, each necessitating an independent sealing device. This not only increases the risk of leakage but also raises maintenance costs. Meanwhile, conventional planetary gearboxes use end-face seals, which are prone to axial clearance due to wear after long-term operation, leading to seal failure. These technical bottlenecks severely restrict the development of underwater propulsion systems towards higher efficiency and greater compactness. Summary of the Invention
[0005] To address the aforementioned problems, the purpose of this invention is to provide an underwater propulsion device that features a compact structure, high transmission efficiency, and excellent sealing performance.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: This application provides an underwater propulsion device, the technical solution of which is as follows: An underwater propulsion device, characterized in that it includes: a bottom shell; a drive motor, a gearbox, and a propeller disposed inside the bottom shell; the gearbox includes: a gearbox housing; a planetary gear assembly disposed inside the gearbox housing; an output shaft connected to the planetary gear assembly; the planetary gear assembly includes: a gear ring fixed to the inner wall of the gearbox housing, the inner surface of which is provided with internal teeth; a planet carrier located inside the gear ring; a plurality of planet gears arranged circumferentially on the planet carrier and capable of relative rotation, the outer sides of the planet gears meshing with the internal teeth of the gear ring; a sun gear located inside the planet carrier and meshing with the planet gears; the sun gear being connected to the output end of the drive motor; the output shaft being connected to the planet carrier and driven by the propeller.
[0007] Furthermore, this application also proposes that the planetary carrier includes: a top plate; a bottom plate opposite to the top plate; a plurality of connecting beams circumferentially spaced between the top plate and the bottom plate; a pocket formed between two adjacent connecting beams; and planetary gears rotatably mounted in the pockets via a rotating shaft.
[0008] Furthermore, this application also proposes that the gearbox housing is sealed to the rear end of the bottom shell, and the two together form a streamlined outer shell.
[0009] Furthermore, this application also proposes that the front end of the gearbox housing is sealed with an end cover; the sun gear is rotatably supported by a bearing on the inner side of the end cover; the output shaft of the drive motor passes through the central hole of the end cover and is coaxially connected with the sun gear.
[0010] Furthermore, this application also proposes that the inner side of the end cover is provided with an inner sealing ring extending toward the shaft center; the inner sealing ring is provided with an annular groove, and a first sealing ring is fitted inside the groove; when the end cover is connected to the gearbox housing, the inner sealing ring extends into the gearbox housing and forms a radial seal with the inner wall of the housing.
[0011] Furthermore, this application also proposes that the front outer wall of the gearbox housing is provided with a first sealing ring portion; the side wall of the end cover is provided with a second sealing ring portion; the first sealing ring portion and the second sealing ring portion are respectively provided with annular grooves, and a second sealing ring is sleeved in the grooves; when the gearbox housing is connected to the bottom shell, the first sealing ring portion and the second sealing ring portion extend into the interior of the bottom shell and form a radial seal with the inner wall of the bottom shell.
[0012] Furthermore, this application also proposes that the outer peripheral wall of the output shaft is provided with multiple protruding positioning teeth along the circumferential direction; the inner edge of the shaft hole of the propeller is provided with multiple positioning grooves along the circumferential direction; when the propeller is assembled on the output shaft, the positioning teeth and the positioning grooves mesh and match to realize circumferential linkage transmission.
[0013] As can be seen from the above, the underwater propulsion device and its planetary gear transmission structure provided in this application, through the cooperative design of planetary gear assembly and sealing structure, effectively resists water pressure deformation and leakage risks while ensuring transmission accuracy, and has the advantages of compact structure, high transmission efficiency and excellent sealing performance. Attached Figure Description
[0014] Figure 1 This is a three-dimensional schematic diagram of an underwater thruster provided in this application.
[0015] Figure 2 This is a schematic diagram of the installation of an underwater thruster provided in this application.
[0016] Figure 3 This is a cross-sectional schematic diagram of an underwater thruster provided in this application.
[0017] Figure 4 This is a schematic diagram of the end cap structure.
[0018] Figure 5 This is a schematic diagram of the internal structure of the gearbox housing.
[0019] Figure 6 This is a schematic diagram of the planetary carrier structure. Detailed Implementation
[0020] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.
[0021] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more, unless otherwise expressly defined.
[0023] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0024] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0025] In existing technologies, underwater propulsion devices generally employ parallel-shaft gear transmission structures. The multi-stage gear pairs arranged sequentially along the axial direction result in a lengthy overall structure, making it difficult to adapt to the installation requirements of miniaturized equipment. Such transmission systems face challenges in sealing reliability in deep-water environments, and accumulated gear meshing errors can easily lead to vibration and energy loss. While traditional planetary gearboxes offer the advantage of compact structure, the conflict between dynamic sealing of rotating components and the shell's resistance to deformation limits their application in underwater propulsion.
[0026] To address these issues, designers discovered that the excessive axial dimension of parallel shaft drives stemmed from the linear extension of the power transmission path, while conventional planetary gearboxes failed to effectively utilize radial space. By analyzing the motion characteristics of the planetary gear train, they proposed integrating the fixed gear ring with the housing to eliminate the need for a rotary seal, while simultaneously using the planetary carrier output shaft to directly drive the propeller, shortening the transmission chain. This approach breaks away from the traditional independent sealing design of planetary gearboxes, integrating the gear train support structure with the propeller housing function.
[0027] like Figure 1-6As shown, this embodiment proposes an underwater propulsion system including a bottom shell 10, a drive motor 20, a transmission gearbox 30, and a propeller 40. The transmission gearbox 30 includes a gearbox housing 31 and an internal planetary gear assembly, which consists of a fixed ring gear 321, a planet carrier 322, circumferential planetary gears 323, and a sun gear 324. The sun gear 324 is connected to the output end 21 of the drive motor, and the planet carrier 322 is connected to the output shaft 33 to drive the propeller 40. The bottom shell 10 refers to a rigid shell structure that supports the internal components of the propulsion system; it can be die-cast from aluminum alloy and provides an installation reference for the drive motor 20 and the transmission gearbox 30. The planetary gear assembly is a reduction mechanism that transmits power through a planetary gear train; it can be implemented using a three-stage planetary gear train, amplifying torque by inputting power through the sun gear 324 and outputting power through the planet carrier 322. The ring gear 321 is an annular component with internal teeth, which can be fixed by pressing it into the inner wall of the gearbox housing 31 with an interference fit, forming a static meshing reference for the planetary gear train. The planetary carrier 322 refers to the frame structure that supports the rotation of the planetary gears 323. Specifically, it can be implemented using a hollow bracket with pockets 3224, and the axial positioning accuracy of the planetary gears 323 is maintained by the connecting beam 3223. The output shaft 33 refers to the shaft-shaped component that transmits rotational power. Specifically, it can be implemented using a stainless steel stepped shaft, with its front end connected to the planetary carrier 322 by a key, and its rear end extending to the mounting position of the propeller 40.
[0028] Specifically, the drive motor output 21 is directly connected to the sun gear 324, and the power is split through the planetary gears 323 to the fixed ring gear 321 and the rotating planetary carrier 322. Since the ring gear 321 is rigidly fixed to the inner wall of the gearbox housing 31, the planetary gears 323, as they revolve around the sun gear 324, force the planetary carrier 322 to rotate at reduced speed. The planetary carrier 322 transmits the rotational motion to the output shaft 33, driving the propeller 40 to generate thrust. The circumferentially distributed design of the planetary gears 323 cancels out the meshing forces, reducing the vibration amplitude of the gearbox. The gearbox housing 31 and the bottom shell 10 are connected in a streamlined manner, reducing turbulence resistance when water flows through the outer shell. This solution achieves the same reduction ratio within a single-stage reduction mechanism through the radial layout of the planetary gear system, reducing axial space occupation. Compared to the conventional independent sealing design of planetary gearboxes, this solution integrates the ring gear 321 with the housing, avoiding the dynamic sealing problem of the rotating part of the planetary carrier 322, while utilizing the overall rigidity of the bottom shell 10 to improve the stability of gear meshing accuracy. Through the above technical solutions, this application effectively shortens the axial dimension of the thruster, meeting the installation requirements of small underwater equipment. The uniform load distribution characteristic of the planetary gear train reduces gear wear rate and extends the service life of the transmission system. The fixed gear ring 321 design simplifies the housing sealing structure and improves operational reliability in deep-water environments. The planetary carrier 322 directly outputs power, reducing intermediate transmission links and lowering energy transmission losses and noise radiation levels.
[0029] like Figure 6As shown, the planetary carrier 322 includes a top plate 3221, a bottom plate 3222 opposite to the top plate 3221, and multiple connecting beams 3223 circumferentially spaced between the top plate 3221 and the bottom plate 3222. A pocket 3224 is formed between adjacent connecting beams 3223, and the planetary gears 323 are rotatably mounted within the pocket 3224 via a rotating shaft. The top plate 3221 is a plate-like structure covering one axial end of the planetary carrier 322. It can be made of cast aluminum alloy or stamped steel plate, and its outer diameter is clearance-fitted with the inner wall of the gearbox housing 31, serving to form the axial positioning reference surface of the planetary gears 323 together with the bottom plate 3222. The bottom plate 3222 is a plate-like structure arranged parallel to the top plate 3221, and can be made of the same material and using the same forming process as the top plate 3221. Its inner edge is interference-fitted with the output shaft 33, serving to transmit the rotational power of the planetary carrier 322 to the output shaft 33. The connecting beam 3223 refers to the strip-shaped support evenly distributed circumferentially between the top plate 3221 and the bottom plate 3222. It can be connected to the top plate 3221 and the bottom plate 3222 by welding or integral casting, forming a rigid partition between adjacent pockets 3224 to distribute the radial load transmitted by the planetary gear 323. The pocket 3224 refers to the rectangular or trapezoidal space enclosed by two adjacent connecting beams 3223 and the top plate 3221 and the bottom plate 3222. It can be formed into a regular geometric shape by milling or casting, accommodating the planetary gear 323 and restricting its radial displacement. The rotating shaft refers to the cylinder passing through the central hole of the planetary gear 323. It can be a stainless steel pin or a carbide shaft, with both ends fixed to the side walls of the connecting beam 3223 by snap rings or threads, supporting the rotational motion of the planetary gear 323. Specifically, the top plate 3221 and the bottom plate 3222 form a closed frame structure through circumferentially distributed connecting beams 3223, constraining the planetary gears 323 within the pockets 3224 formed by the top plate 3221, the bottom plate 3222, and the connecting beams 3223 on both sides. The radial force generated by the planetary gears 323 during meshing is dispersed by the connecting beams 3223 to the top plate 3221 and the bottom plate 3222, preventing localized stress concentration that could lead to deformation of the planetary carrier 322. The sidewalls of the pockets 3224 form surface contact with the shaft, suppressing axial movement of the planetary gears 323 during high-speed rotation. Simultaneously, rolling bearings or lubrication bushings are installed between the shaft and the inner bore of the planetary gears 323 to reduce frictional resistance. The symmetrical layout of the top plate 3221 and the bottom plate 3222 ensures the planetary carrier 322 remains balanced under bidirectional axial loads, while the circumferentially spaced connecting beams 3223 ensure structural rigidity while providing a channel for the flow of lubricating oil within the gearbox housing 31.
[0030] like Figure 2-5As shown, the gearbox housing 31 is sealed to the rear end of the bottom shell 10, and the two together form a streamlined outer shell. The sealed connection of the gearbox housing 31 to the rear end of the bottom shell 10 means that the gearbox housing 31 and the rear end of the bottom shell 10 are fixedly connected by a sealing structure. This can be achieved using a flange connection with a sealing gasket, or an interference fit with sealant. This connection method reduces the assembly gap between the separate housings, shortening the axial length of the transmission system. The streamlined outer shell refers to the shape structure with a continuous smooth curved surface formed by the combination of the gearbox housing 31 and the bottom shell 10. This can be achieved through the curved transition design of the housing mating parts, for example, designing the rear end of the gearbox housing 31 as a tapered cone that smoothly connects with the arc-shaped tail of the bottom shell 10. This structure reduces fluid resistance during underwater propulsion by eliminating the step-like abrupt change at the housing connection. Specifically, the sealed connection between the rear ends of the gearbox housing 31 and the bottom shell 10 forms an integral structure, optimizing the axial layout of the transmission system and the propeller housing. The gearbox housing 31, serving as the load-bearing structure of the transmission assembly, directly eliminates the assembly space between traditional split housings by sealing its connection with the bottom housing 10, thus reducing the axial dimension of the propeller. The streamlined curved surface formed by the combination of the two housings allows water to flow smoothly along the outer surface, avoiding turbulence caused by abrupt changes in shape at the housing connection. This structure simplifies the sealing interface of the transmission system from traditional multi-stage sealing to a single sealing surface, reducing the risk of leakage caused by complex sealing structures.
[0031] As shown in Figures 4 and 5, an end cover 34 is sealed to the front end of the gearbox housing 31. The sun gear 324 is rotatably supported by a bearing inside the end cover 34. The output shaft of the drive motor 20 passes through the central hole of the end cover 34 and is coaxially connected to the sun gear 324. The end cover 34 is a closed component covering the front opening of the gearbox housing 31. It can be made of metal or engineering plastic in a ring-shaped disc structure and is detachably connected to the gearbox housing 31 via bolts or clips, serving to isolate the gearbox interior from the external environment. The bearing is a mechanical element used to support rotating components. It can be a deep groove ball bearing or an angular contact bearing, installed in a bearing housing inside the end cover 34, used to constrain the radial runout of the sun gear 324 and reduce rotational friction. The central hole is a through hole located at the geometric center of the end cover 34. It can be a precision-machined circular channel matching the diameter of the drive motor 20's output shaft, used to achieve a non-eccentric connection between the motor shaft and the sun gear 324. Specifically, the end cap 34 covers the front end of the gearbox housing 31 through a sealed connection, forming the first barrier to prevent external water from entering the gearbox. The bearing installed inside the end cap 34 directly supports the sun gear 324 radially, ensuring the sun gear 324 maintains a stable rotational axis when transmitting torque to the drive motor 20, avoiding shaft misalignment caused by the cantilever structure. The output shaft of the drive motor 20 passes through the center hole of the end cap 34 and is coaxially connected to the sun gear 324, ensuring the power transmission path extends in a straight line and eliminating the shaft misalignment error common in multi-stage transmissions. The sealed connection interface between the end cap 34 and the gearbox housing 31, and the fit clearance between the center hole and the motor shaft, together constitute a double sealing barrier, preventing external water from axially penetrating into the gearbox.
[0032] In the specific design, the inner side of the end cover 34 is provided with an inner sealing ring 341 extending towards the axis. The inner sealing ring 341 has an annular groove, and a first sealing ring 51 is fitted inside the groove. When the end cover 34 is connected to the gearbox housing 31, the inner sealing ring 341 extends into the gearbox housing 31 and forms a radial seal with the inner wall of the housing. The inner sealing ring 341 refers to an annular protrusion extending from the inner side of the end cover 34 towards the axis. It can be implemented using a metal ring or engineering plastic ring integrally formed with the end cover 34. Its extension length can cover the radial sealing area of the inner wall of the gearbox housing 31, establishing a radial fit with the inner wall of the housing. The annular groove refers to a groove structure circumferentially formed along the inner sealing ring 341. It can be formed by turning or injection molding, and the groove depth can be slightly larger than the diameter of the sealing ring cross-section, used to accommodate and fix the sealing ring. The first sealing ring 51 is an elastic sealing element fitted into the annular groove. It can be made of nitrile rubber or fluororubber, and its cross-sectional shape can be circular or rectangular. It forms a contact seal with the inner wall of the housing through radial compression deformation. Specifically, when the end cover 34 is assembled to the gearbox housing 31, the inner sealing ring 341 inserts into the inner cavity of the housing, causing the sealing ring fitted into the annular groove to be radially compressed by the inner wall of the housing. During gearbox operation, the contact pressure generated by the elastic deformation of the sealing ring can simultaneously resist the leakage of internal lubricating oil and the intrusion of external water pressure. As the gearbox speed increases, centrifugal force causes the sealing ring to further tighten against the inner wall of the housing, forming a dynamic self-tightening effect. The radial fit between the inner sealing ring 341 and the inner wall of the housing ensures that the sealing interface is always perpendicular to the pressure direction, avoiding gap changes caused by axial pressure fluctuations in traditional end-face seals. Through the above technical solution, this application effectively prevents external water from seeping into the gearbox through the connection between the end cover 34 and the housing in deep-water, high-pressure environments, while also preventing internal lubricating oil leakage. The uniform contact pressure formed by the sealing ring under radial compression can adapt to the changes in centrifugal force generated by the high-speed rotation of the gearbox, maintaining the stability of the sealing interface. The radial fit structure between the inner sealing ring 341 and the inner wall of the housing enhances the pressure resistance of the sealing system, ensuring long-term sealing even under dynamic operating conditions.
[0033] Furthermore, a first sealing ring 311 is provided on the front outer wall of the gearbox housing 31, and a second sealing ring 342 is provided on the side wall of the end cover 34. The first sealing ring 311 and the second sealing ring 342 each have an annular groove, and a second sealing ring 52 is fitted inside the groove. When the gearbox housing 31 is connected to the bottom shell 10, the first sealing ring 311 and the second sealing ring 342 extend into the bottom shell 10 and form a radial seal with the inner wall of the bottom shell 10. The first sealing ring 311 refers to the annular protrusion structure provided on the front outer wall of the gearbox housing 31. Specifically, it can be implemented using a machined metal ring, with an outer diameter slightly smaller than the inner wall of the bottom shell 10. Radial compression deformation is achieved through the sealing ring in the annular groove. The second sealing ring 342 refers to the annular protrusion structure provided on the side wall of the end cover 34. Specifically, it can be implemented using a plastic or metal ring integrally formed with the end cover 34. Its outer diameter forms a stepped fit with the first sealing ring 311, achieving a separate sealing contact through the sealing ring in the annular groove. An annular groove refers to a groove structure formed on the surface of the sealing ring, which can be formed by turning or injection molding, and is used to accommodate and fix the sealing ring. The second sealing ring 52 is an elastic annular seal, which can be made of nitrile rubber or fluororubber, and expands radially under pressure to fill the assembly gap.
[0034] Specifically, when the gearbox housing 31 is assembled with the bottom shell 10, the second sealing ring 342 on the end cover 34 first contacts the inner wall of the bottom shell 10. The second sealing ring 52 in the annular groove expands outward after being squeezed, filling the microscopic gap between the housings. Subsequently, the first sealing ring 311 of the gearbox housing 31 extends further into the bottom shell 10, and the second sealing ring 52 in its annular groove undergoes radial deformation under the action of axial assembly force, forming a second sealing interface. The stepped distribution of the two sealing rings causes the sealing contact surfaces to be staggered axially, and the water pressure load is distributed to two independent sealing areas. Through the above technical solution, this application effectively prevents water infiltration at the connection between the gearbox housing 31 and the bottom shell 10, ensuring the sealing reliability of the propeller under high-speed rotation and deep water pressure. The combined structure of the two sealing rings forms a redundant sealing barrier, so even if one sealing ring wears, the other sealing interface can still maintain an effective seal. The split sealing ring design reduces the requirements for the coaxiality of the housing machining and reduces the risk of leakage due to assembly errors. The stepped distribution of the sealing interface extends the seepage path and improves the sealing structure's resistance to instantaneous pressure shocks.
[0035] like Figure 6As shown, the outer peripheral wall of the output shaft 33 is provided with multiple protruding positioning teeth 331 along the circumferential direction, and the inner edge of the shaft hole of the propeller 40 is provided with multiple positioning grooves along the circumferential direction. When the propeller 40 is assembled on the output shaft 33, the positioning teeth 331 and the positioning grooves mesh and match, realizing circumferential linkage transmission. The positioning teeth 331 refer to the protruding structures extending circumferentially along the outer peripheral wall of the output shaft 33. Specifically, they can be implemented using metal racks with trapezoidal or rectangular cross sections, and they are continuously distributed along the axial direction to enhance torsional resistance. The positioning grooves refer to the grooves on the inner edge of the shaft hole of the propeller 40 that are complementary in shape to the positioning teeth 331. Specifically, they can be formed by precision milling, and the groove depth matches the height of the positioning teeth 331 to ensure no gaps on the meshing surface. The meshing relationship between the positioning teeth 331 and the positioning grooves avoids single-point stress concentration through multi-tooth uniform load distribution, and at the same time eliminates the assembly clearance error of traditional keyway connections. Specifically, when the output shaft 33 rotates, the meshing surfaces of the positioning teeth 331 and the positioning grooves form rigid contact, and the power is directly transmitted to the propeller 40 through the mechanical extrusion of the tooth sides. The locating teeth 331 are evenly distributed circumferentially, ensuring that each tooth bears the torque load synchronously and avoiding tooth surface wear caused by local overload. The locating groove inside the propeller shaft hole forms an angular alignment constraint with the locating teeth 331 during assembly, ensuring that the propeller blades 40 and the rotation center of the output shaft 33 are strictly coaxial. When the propeller is subjected to water flow impact or sudden load changes, the multi-tooth meshing structure disperses the impact stress by increasing the contact area, preventing transmission failure caused by circumferential slippage or misalignment.
[0036] In summary, the underwater propulsion device and its planetary gear transmission structure provided in this application, through the cooperative design of the planetary gear assembly and the sealing structure, effectively resists the risk of water pressure deformation and leakage while ensuring transmission accuracy. It has the advantages of compact structure, high transmission efficiency and excellent sealing performance.
[0037] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0038] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.
Claims
1. An underwater propulsion device, characterized in that, include: Bottom shell (10); The drive motor (20), the gearbox (30) and the propeller (40) are installed inside the bottom shell (10). The gearbox (30) includes: Gearbox housing (31); Planetary gear assembly disposed within the gearbox housing (31); The output shaft (33) is connected to the planetary gear assembly. The planetary gear assembly includes: The gear ring (321) fixed to the inner wall of the gearbox housing (31) has internal teeth on its inner surface; Planet carrier (322) located inside the gear ring (321); A plurality of planetary gears (323) are arranged circumferentially on the planet carrier (322) and can rotate relative to each other, the outer side of the planetary gears (323) meshing with the inner teeth of the gear ring (321); The sun gear (324) located inside the planet carrier (322) meshes with the planet gear (323); The sun gear (324) is connected to the output end (21) of the drive motor (20); The output shaft (33) is connected to the planetary carrier (322) and is driven by the propeller (40); The gearbox housing (31) is sealed to the rear end of the bottom shell (10), and the two are combined to form a streamlined outer shell; The front end of the gearbox housing (31) is sealed with an end cover (34); the inner side of the end cover (34) is supported by a bearing for rotating the sun gear (324); the output shaft of the drive motor (20) passes through the center hole of the end cover (34) and is coaxially connected with the sun gear (324); The end cap (34) has an inner sealing ring (341) extending toward the axis on its inner side; the inner sealing ring (341) has an annular groove, and a first sealing ring (51) is fitted inside the groove; when the end cap (34) is connected to the gearbox housing (31), the inner sealing ring (341) extends into the gearbox housing (31) and forms a radial seal with the inner wall of the housing; The front outer wall of the gearbox housing (31) is provided with a first sealing ring (311); the side wall of the end cover (34) is provided with a second sealing ring (342); the first sealing ring (311) and the second sealing ring (342) are respectively provided with annular grooves, and a second sealing ring (52) is sleeved in the grooves; when the gearbox housing (31) is connected to the bottom shell (10), the first sealing ring (311) and the second sealing ring (342) are combined and extended into the bottom shell (10), and form a radial seal with the inner wall of the bottom shell (10).
2. The underwater thruster according to claim 1, characterized in that: The planetary carrier (322) includes: Top plate (3221); The bottom plate (3222) is opposite to the top plate (3221); Multiple connecting beams (3223) are circumferentially spaced between the top plate (3221) and the bottom plate (3222); A pocket (3224) is formed between two adjacent connecting beams (3223); The planetary gear (323) is rotatably mounted in the pocket (3224) via a pivot.
3. The underwater thruster according to claim 1, characterized in that: The outer peripheral wall of the output shaft (33) is provided with a plurality of protruding positioning teeth (331) along the circumferential direction; the inner edge of the shaft hole of the propeller (40) is provided with a plurality of positioning grooves along the circumferential direction; when the propeller (40) is assembled on the output shaft (33), the positioning teeth (331) and the positioning grooves mesh and match to realize circumferential linkage transmission.