Low-vibration propulsion motor with embedded pressure compensation mechanism and application of low-vibration propulsion motor

Abstract

The invention discloses a low-vibration propulsion motor with an embedded pressure compensation mechanism and application of the low-vibration propulsion motor. The low-vibration propulsion motor comprises a stator, a rotor and a pressure compensation mechanism which are installed in a first inner cavity in a motor shell. The pressure compensation mechanism comprises a shell-shaped base body with a second inner cavity, an elastic element and a flexible rolling diaphragm; the elastic element is installed in the shell-shaped base body and connected with the flexible rolling diaphragm, the flexible rolling diaphragm is arranged between the second inner cavity and the first inner cavity, and the second inner cavity is communicated with the external environment and is isolated from the first inner cavity of the motor shell in a sealed mode. The low-vibration propulsion motor has the advantages of low vibration, low noise and the like, especially by adopting the embedded pressure compensation mechanism, the size of the motor can be remarkably reduced, the self weight of the motor is reduced, the thrust-weight ratio of the motor is improved, the motor can adapt to different diving depths and can stably run in deep water for a long time, meanwhile, the overall heat dissipation performance of the motor is improved, and the service life of the motor is prolonged. And the working stability is improved.

Description

Technical Field

[0001] The present application relates to an underwater propeller, and in particular to a low-vibration propulsion motor with an embedded pressure compensation mechanism and its application in underwater vehicles. Background Art

[0002] As a core power component of deep-sea equipment, underwater propulsion motors must simultaneously meet low vibration and noise requirements, high pressure resistance, and lightweight requirements. Currently, mainstream underwater propulsion motors utilize oil-filled pressure compensation technology: high-voltage insulating oil (such as mineral oil or synthetic esters) is filled within the motor cavity, and external water pressure is transmitted through the oil to balance internal and external pressures. While this technology effectively prevents housing deformation and ensures insulation performance, it suffers from drawbacks such as excessive weight, limited dynamic response, and complex thermal management, necessitating urgent improvements. Specifically, achieving kilometer-level pressure resistance (≥10 MPa) requires thicker and more reinforced motor housings. Furthermore, the high density of high-voltage insulating oil significantly increases overall weight, significantly reducing the thrust-to-weight ratio of the propulsion system. Furthermore, high-density oil increases the rotor's moment of inertia, limiting the motor's start-up, shutdown, and speed regulation response. Furthermore, the viscosity of high-voltage insulating oil varies significantly with temperature, necessitating the design of an additional oil circulation cooling system, further increasing structural complexity and weight. Summary of the Invention

[0003] The main purpose of this application is to provide a low-vibration propulsion motor with an embedded pressure compensation mechanism and its application to overcome the defects of the prior art.

[0004] In order to achieve the above-mentioned purpose of the invention, this application provides the following technical solutions.

[0005] A first aspect of the present application provides a low-vibration propulsion motor with an embedded pressure compensation mechanism, comprising a motor housing and a stator, a rotor, and a rotating shaft installed in a first inner cavity within the motor housing, wherein the rotating shaft is connected to the rotor, the rotating shaft is rotationally engaged with the motor housing via a bearing, and is rotationally and sealingly engaged with the motor housing via a mechanical dynamic seal structure, wherein the first inner cavity is isolated from the external environment at least via the mechanical dynamic seal structure, and the first inner cavity is further filled with insulating oil having a set pressure, and the insulating oil fills the first inner cavity; The propulsion motor also includes a pressure compensation mechanism fixedly arranged in the motor housing, the pressure compensation mechanism including a shell-shaped base having a second inner cavity, an elastic element and a flexible rolling diaphragm, the second inner cavity is connected to the external environment and is sealed and isolated from the first inner cavity, the flexible rolling diaphragm is fixed and sealed to the shell-shaped base, the flexible rolling diaphragm is between the second inner cavity and the first inner cavity, and is in direct contact with the insulating oil filled in the first inner cavity, the elastic element is installed in the second inner cavity, the elastic element is fixedly connected to the shell-shaped base, and is in contact or connection with the flexible rolling diaphragm, and the flexible rolling diaphragm can produce deformation toward the first inner cavity or the second inner cavity under the action of external force, and the external force is the combined force of the elastic force of the elastic element, the pressure of the insulating oil filled in the first inner cavity, and the ambient pressure in the second inner cavity.

[0006] Furthermore, the axial directions of the elastic element and the second inner cavity are parallel to the axial direction of the rotating shaft; one end of the elastic element is fixedly connected to the shell-shaped base, and the other end is connected to the flexible rolling diaphragm.

[0007] Furthermore, the aspect ratio of the elastic element is , the pressure compensation mechanism satisfies: ; Where m is the mass of the elastic element, c is the damping of the elastic element, t is the duration of deformation of the elastic element, A is the effective pressure-bearing area of ​​the pressure compensation mechanism, P is the pressure of the insulating oil, k is the stiffness of the elastic element, and x is the deformation of the elastic element.

[0008] Furthermore, the pressure compensation mechanism further includes a guide post, which is fixedly disposed in the second inner cavity, and the elastic element is sleeved on the guide post, and the elastic element is restricted to elastically expand and contract along the axial direction of the guide post.

[0009] Furthermore, the axial direction of the guide pillar is parallel to the axial direction of the elastic element.

[0010] Furthermore, the motor housing is provided with one or more seawater introduction holes, which are connected to the second inner cavity, so that seawater in the external environment can flow freely between the external environment and the second inner cavity through the seawater introduction holes.

[0011] Furthermore, the motor housing includes a front flange, a motor housing body and a rear flange connected in sequence along the axial direction, the stator is fixedly matched with the motor housing body, the rotating shaft is rotatably matched with the front flange and the rear flange via the two bearings respectively, the mechanical dynamic sealing structure is arranged between the rear flange and the rotating shaft, the pressure compensation mechanism is fixedly connected to the front flange, and the interior of the rotating shaft is hollow, the pressure compensation mechanism is arranged as a whole inside the rotating shaft, there is no direct contact between the pressure compensation mechanism and the rotating shaft, the gap between the pressure compensation mechanism and the rotating shaft is connected to the first inner cavity, and the seawater inlet hole is arranged on the front flange.

[0012] Furthermore, a seawater introduction channel is provided in the front flange, the seawater introduction channel is communicated with the seawater introduction hole and the second inner cavity respectively, and the seawater introduction channel is sealed and isolated from the first inner cavity.

[0013] Furthermore, the gap between the stator and the rotor and the gap between the rotating shaft and the bearing are directly connected to the first inner cavity, and the insulating oil medium is also filled in the gap between the stator and the rotor, the gap between the rotating shaft and the bearing, and the gap of the bearing, and forms a pressure-bearing oil film in the gap between the stator and the rotor, the gap between the rotating shaft and the bearing, and the gap of the bearing, respectively.

[0014] Furthermore, the bearing comprises a sliding bearing having a tubular structure, wherein one end of the tubular structure close to the rotor extends radially outward to form an annular protrusion.

[0015] Furthermore, the sliding bearing is an L-shaped tubular structure.

[0016] Furthermore, the pressure-bearing oil film between the sliding bearing and the rotating shaft is a wedge-shaped oil film structure. When the rotor rotates, the pressure of the wedge-shaped oil film structure increases as the speed of the rotor rotation increases.

[0017] Furthermore, the gap between the sliding bearing and the rotating shaft is an annular gap, and the width of the annular gap is D / 1000~2D / 1000, where D is the outer diameter of the sliding bearing.

[0018] Furthermore, the bearing is provided with an oil hole running through the bearing, the oil hole is communicated with the first inner cavity, and the insulating oil is also filled in the oil hole.

[0019] In a more typical embodiment, a resolver encoder is further provided in the rear flange, and the resolver encoder is used to monitor the working status of the propulsion motor. The resolver encoder and the rotor have the same number of pole pairs.

[0020] In a more typical embodiment, the front end of the low-vibration propulsion motor is also sealed and connected with a watertight connector, and a power wire groove is opened on the inner wall of the motor housing. The power wire passes through the power wire groove to electrically connect the power terminal of the watertight connector with the stator and / or rotor.

[0021] Furthermore, the watertight connector is sealed and connected to the front flange.

[0022] In a more typical embodiment, the rotating shaft includes a first shaft segment and a second shaft segment fixedly connected along the axial direction, the first shaft segment is composed of a magnetic metal material and serves as the rotor core, the second shaft segment is composed of a corrosion-resistant material, the first shaft segment is entirely arranged in the motor housing, and the second shaft segment is partially arranged outside the motor housing.

[0023] Furthermore, a plurality of seawater flow channels are provided on the outer wall of the motor housing, and the seawater flow channels continuously cross the outer wall of the motor housing along the axial direction.

[0024] Furthermore, the seawater flow channel includes a groove structure provided on the outer wall of the motor housing and extending continuously in the axial direction.

[0025] Furthermore, a plurality of seawater flow channels are sequentially arranged along the axial direction of the motor housing.

[0026] A second aspect of the present application provides an underwater vehicle comprising the low-vibration propulsion motor with a built-in pressure compensation mechanism.

[0027] Compared with the existing technology, the technical solution provided by this application has at least the following advantages: The present application integrates the pressure compensation mechanism in the propulsion motor and injects insulating oil with a certain pressure into the propulsion motor, forcing the elastic element in the pressure compensation mechanism to maintain a certain deformation. This can maintain a certain pressure in the propulsion motor and a certain pressure difference between the inside and the outside, thereby achieving a pressure compensation effect. This can effectively ensure the sealing of the propulsion motor at different diving depths and reduce or eliminate the leakage of the insulating oil medium.

[0028] The present application sets a pressure compensation mechanism in the propulsion motor, and uses the aforementioned seawater inlet hole to introduce seawater into the pressure compensation mechanism so that the interior is filled with seawater. This can form a pressure difference between the interior of the pressure compensation mechanism and the interior of the propulsion motor, thereby achieving a pressure compensation effect. At the same time, it is also beneficial to effectively reduce the volume of the propulsion motor, thereby reducing the weight of the oil filling and reducing the weight of the propulsion motor overall.

[0029] Compared with the method of filling high-voltage insulating oil in the propulsion motor, this application integrates the pressure compensation mechanism into the rotating shaft, which not only eliminates the need to thicken the motor casing to improve its pressure-bearing capacity, but also allows the thickness of the motor casing to be appropriately thinned, which is conducive to the lightweighting of the propulsion motor.

[0030] The present application sets multiple seawater flow channels on the outer wall of the motor housing and adopts the design of integrated axial seawater flow channels in the motor housing. When the propulsion motor is working, the external water flow is forced to convect along the propulsion direction, so that flow channels in the direction of water flow are generated outside the propulsion, the fluidity of the fluid is increased, and the propulsion motor can dissipate heat better, and the propulsion resistance can also be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0032] Figure 1 2 is a schematic cross-sectional structural diagram of a low-vibration propulsion motor with a built-in pressure compensation mechanism in an embodiment of the present application; Figure 2 2 is a schematic cross-sectional structural diagram of a low-vibration propulsion motor with a built-in pressure compensation mechanism in an embodiment of the present application; Figure 3 2 is a schematic cross-sectional structural diagram of a low-vibration propulsion motor with a built-in pressure compensation mechanism in an embodiment of the present application; Figure 4 This is a schematic cross-sectional structure diagram of a low-vibration propulsion motor with an embedded pressure compensation mechanism in an embodiment of the present application. DETAILED DESCRIPTION

[0033] The technical solution of the present application will be further described below in conjunction with specific embodiments. However, the implementation of the present application is not limited to these specific details, and may also be implemented in other ways different from those described herein. Therefore, the specific embodiments presented in the present application are only for illustration and not for limitation.

[0034] See also Figures 1-4 A low-vibration propulsion motor with an embedded pressure compensation mechanism 800 includes components such as a motor housing 100, a stator, a rotor, a rotating shaft, and a pressure compensation mechanism 800.

[0035] The configuration structure of the motor housing 100, stator, rotor, and rotating shaft is the same or substantially the same as that of conventional motors known in the art. The configuration structure of the motor housing 100, stator, rotor, and rotating shaft will be described in detail below.

[0036] Specifically, the interior of the motor housing 100 has a first inner cavity, the stator 200 and the rotor 300 are completely encapsulated in the first inner cavity of the motor housing 100, the main part of the rotating shaft 400 is encapsulated in the first inner cavity of the motor housing 100, a part of the rotating shaft 400 extends from the first inner cavity of the motor housing 100 and is fixedly connected to the propeller, wherein the stator 200 is sleeved on the rotor 300, the rotor 300 rotates with the stator 200, the stator 200 is fixedly connected to the motor housing 100, the rotor 300 is sleeved on the rotating shaft 400 and is connected to the rotating shaft 400, and the rotor 300 and the rotating shaft 400 are both connected to the motor housing 10 0 rotational fit, in order to ensure the airtightness of the first inner cavity in the motor housing 100, a mechanical dynamic sealing structure 600 is provided in the first inner cavity of the motor housing 100, and the mechanical dynamic sealing structure 600 is fixedly provided on the motor housing 100 and is located at the tail section of the motor housing 100. The mechanical dynamic sealing structure 600 rotates and seals with the part of the rotating shaft close to the part extending out of the first inner cavity, and the first inner cavity is also filled with insulating oil with a set pressure, and the insulating oil fills the first inner cavity. It can be understood that the parts of the stator, rotor, rotating shaft, etc. located in the first inner cavity that are exposed to the first inner cavity are all covered / wrapped by the insulating oil.

[0037] It should be noted that the stator, rotor and rotating shaft are the basic structures of the motor. The configuration structure of the three and the configuration structure for realizing the rotational drive of the rotating shaft are known in the art. They are not used as improved structures of this application, so no specific limitation is made. Those skilled in the art can adopt any method / structure known in the art for configuration.

[0038] Specifically, the stator 200 is fixedly matched with the motor housing 100 through a structure / method known in the art. In the radial direction, there is a gap between the stator 200 and the rotor 300, and the rotor 300 and the rotating shaft 400 also have the freedom to move in the axial direction. The structure of the stator 200 and the rotor 300 can adopt a structure known in the art. The configuration structure between the stator 200 and the rotor 300 is also known in the art and is not specifically limited here. In this embodiment, except for the stator 200 core, winding, etc., the remaining components can be encapsulated by epoxy resin to ensure reliability.

[0039] For example, the stator 200 can be made of high-quality silicon steel sheets. A high-strength composite epoxy resin is poured into the stator 200. Compared to conventional motor glue potting, this resin has higher rigidity, better thermal conductivity, insulation, and better aging resistance. Specifically, the contact surfaces between internal parts of the stator 200 are designed with high-pressure sealing rings to prevent seawater penetration. All components of the stator 200 can be made of aluminum alloy, and the high-pressure sealing rings are made of fluororubber. These are lightweight and corrosion-resistant materials that ensure the propeller can operate longer in seawater.

[0040] In this embodiment, the rotor 300 is sheathed with carbon fiber material to ensure that the rotor 300 magnets are completely fixed and can be fully protected under the action of high-speed centrifugal force. The contact surfaces of all stationary parts are designed with high-pressure resistant sealing rings, and the rotor 300 core is epoxy-encapsulated with glue, so the overall sealing performance is excellent.

[0041] Specifically, the rotating shaft 400 is rotationally engaged with the motor housing 100 via two axially spaced sliding bearings 500. These two sliding bearings 500 are primarily used to limit the radial freedom of the rotating shaft 400 and the rotor 300, ensuring that the rotating shaft 400 does not experience radial displacement and maintaining the rotating shaft 400, the rotor 300, and the stator 200 coaxially. Specifically, the two sliding bearings 500 are fixedly engaged with the motor housing 100 using structures / methods known in the art. For example, the sliding bearings 500 can be secured to the motor housing 100 via a mortise and tenon structure and / or auxiliary connectors. It will be understood that the two sliding bearings 500, the rotating shaft, the stator, and the rotor are coaxially arranged.

[0042] Specifically, there is a clearance fit between the stator 200 and the rotor 300, and between the sliding bearing 500 and the rotating shaft 400. The gap between the stator 200 and the rotor 300, the gap between the sliding bearing 500, the thrust sliding bearing 500600 and the rotating shaft 400 are connected to the first inner cavity of the motor housing 100. It can be understood that insulating oil is also filled in the gap between the stator 200 and the rotor 300, the gap between the sliding bearing 500 and the rotating shaft 400, and the gap inside the sliding bearing 500. The insulating oil located in the gap between the stator 200 and the rotor 300 and the gap between the sliding bearing 500 and the rotating shaft 400 forms a pressure-bearing oil film, and the pressure-bearing oil film enables the rotor 300 to form a rotor motion mechanism with low vibration motion.

[0043] It should be noted that the vacant space within the first inner cavity of the motor housing 100 is completely filled with insulating oil, and the pressure within the first inner cavity of the motor housing 100 is maintained above a set value. The set value can be determined based on the maximum submersible depth of the motor, and the two are positively correlated. For example, the set value can be set to 0.2-1 MPa. Exemplary insulating oils include, but are not limited to, insulating oil, white mineral oil, or transformer oil.

[0044] As a preferred solution, the sliding bearing 500 is further provided with an oil hole extending through it, communicating with the first inner cavity. The insulating oil is also filled in the oil hole. This design enhances fluid flow, improves the oil film's load-bearing capacity and damping, and reduces vibration effects. The number and size of the oil holes can be adjusted based on specific circumstances and are not limited here.

[0045] In a typical embodiment, two bearing supports are further disposed within the first inner cavity of the motor housing 100. The bearing supports are fixedly engaged with the motor housing 100, and each bearing support is disposed on the periphery of a corresponding sliding bearing 500 (typically, the bearing support can be sleeved onto the sliding bearing 500). The bearing supports engage with the sliding bearing 500 (possibly through a detachable structure known in the art) and serve to restrict the axial movement of the sliding bearing 500. Typically, the inner annular surface of the bearing support engaging the sliding bearing 500 is provided with a groove-like structure that matches the sliding bearing 500, and the sliding bearing 500 is partially embedded within the groove-like structure, thereby maintaining the position of the sliding bearing 500. Specifically, the sliding bearing 500 can have a straight cylindrical structure or an L-shaped cylindrical structure. One end of the L-shaped cylindrical sliding bearing 500 has an annular protrusion extending radially outward. Part of the sliding bearing 500 can nest with or abut against the rotating shaft 400, the motor housing 100, or the bearing support to form a stop structure, thereby maintaining the position and posture of the sliding bearing 500 within the motor housing 100. For example, the sliding bearing 500 can be a radial sliding bearing 500, and further, a cylindrical hydrodynamic lubrication bearing or a split hydrodynamic lubrication bearing can be used.

[0046] Specifically, the pressure-bearing oil film between the sliding bearing 500 and the rotating shaft 400 is a wedge-shaped oil film structure. When the rotor 300 rotates, the pressure in the wedge-shaped oil film structure increases as the rotor 300's rotational speed increases. Specifically, the gap between the sliding bearing 500 and the rotating shaft 400 is an annular gap (the gap between the inner ring of the sliding bearing 500 and the rotating shaft surface). To ensure a low-vibration motion mechanism, the width of the gap in the sliding bearing 500 is D / 1000 to 2D / 1000, where D is the outer diameter of the sliding bearing 500.

[0047] Specifically, the rotating shaft 400 is divided into two parts, specifically including a first shaft segment 410 and a second shaft segment 420 that are fixedly connected along the axial direction. The first shaft segment 410 is entirely located in the first inner cavity of the motor housing 100. The first shaft segment 410 is connected to the rotor 300 and rotates in a sealed manner with the motor housing 100 via a mechanical dynamic seal structure 600. The second shaft segment 420 is located in the first inner cavity of the motor housing 100 near the first shaft segment 410, and is located outside the motor housing 100 and fixedly connected to the propeller. Alternatively, the second shaft segment 420 can be located entirely outside the first inner cavity. More specifically, the first shaft segment 410 is composed of a magnetically conductive metal material (e.g., magnetically conductive carbon steel) and serves as the core of the rotor 300, thereby enhancing the motor's magnetic circuit. The second shaft segment 420 is composed of a corrosion-resistant material (e.g., stainless steel or a corrosion-resistant titanium alloy) to adapt to the operating environment. Specifically, since the rotating shaft 400 is composed of two parts of materials with a large span and long stroke, the two shaft sections need to be processed separately, and then a wear-resistant coating, such as a tungsten carbide coating, is applied on the surface of each shaft section by spraying or other methods, and finally they are combined together for overall grinding and other processing.

[0048] In a specific embodiment, please refer again to Figure 3 and Figure 4 The motor housing 100 includes a front flange 110, a motor housing body 120, and a rear flange 130 connected in sequence along the axial direction. The stator is fixedly matched with the motor housing body 120. The rotating shaft is rotatably matched with the front flange 110 and the rear flange 130 via the two bearings. The mechanical dynamic sealing structure 600 is provided between the rear flange 130 and the rotating shaft. Specifically, the front flange 110, the motor housing body 120, and the rear flange 130 are fixedly and sealedly connected. The structure for achieving the fixed and sealed connection between the three can adopt a method and structure known in the art and is not limited here. In addition, the mechanical dynamic sealing structure 600 and the configuration structure and method between the mechanical dynamic sealing structure 600 and the motor housing 100 and the rotating shaft are also known in the art and are not limited here.

[0049] Exemplarily, the material of the motor housing 100 can be an aluminum alloy material, which is beneficial to the lightweight of the motor and can slow down or prevent long-term contact corrosion with seawater. Preferably, the outer surface of the motor housing 100 can be hard-oxidized, thereby further slowing down the erosion of the exterior of the propulsion motor from seawater. Preferably, some parts in the motor housing 100, such as the shaft cap, can also be made of sacrificial anode material, so that it cooperates with parts such as the motor housing body 120, the front flange 110, and the rear flange 130 to form a primary battery, which can achieve the effect of slowing down or preventing the motor housing body 120, flanges and other parts from being corroded by seawater.

[0050] In a more preferred embodiment, in order to make the propulsion motor control more precise, a resolver encoder with the same number of pole pairs as the rotor 300 can be provided at one end of the motor housing 100. The resolver encoder is used to monitor the working status of the propulsion motor. The structure of the resolver encoder itself and the configuration structure between it and other components can be implemented in a manner known in the art and are not specifically limited here.

[0051] In addition, it is preferred to seal and connect a watertight connector at the axial center of the front end of the propulsion motor, and a power line groove is provided on the inner wall of the motor housing 100. The power line passes through the power line groove to electrically connect the power terminal of the watertight connector 700 with the windings in the stator and rotor. Specifically, the propulsion motor cable uses a special underwater cable, and the cable is specially sealed. For example, an O-ring is used to wrap the cable, and a pressure cap is placed on the O-ring. The locking force of the screw forces it to deform, so that the O-ring is firmly squeezed onto the motor cable and the workpiece to form a firm seal. Among them, the motor cable, O-ring, etc. can all be purchased commercially, and their specific structure and product model are not limited here.

[0052] With the dynamic changes in diving depth, the pressure difference fluctuation between the inside of the motor and the external environment increases significantly, resulting in a sharp decline in the reliability of the mechanical dynamic sealing structure 600. In particular, the dynamic sealing part is prone to produce micro gaps due to material fatigue or deformation, causing leakage of insulating oil, and then causing problems such as degradation of the internal insulation performance of the motor and reduced heat dissipation efficiency. In severe cases, it may even cause winding short circuit or permanent magnet demagnetization, threatening the safe operation of the spacecraft.

[0053] Based on this, please refer again to Figure 3 and Figure 4The low-vibration propulsion motor in the present application also includes a pressure compensation mechanism 800, which is fixedly arranged in the first inner cavity inside the motor housing 100. The pressure compensation mechanism 800 includes a shell-shaped base 810 with a second inner cavity 811, an elastic element 820 and a flexible rolling diaphragm 830. The shell-shaped base 810 is fixedly connected to the motor housing 100. The second inner cavity 811 of the pressure compensation mechanism 800 is communicated with the external environment and is sealed and isolated from the first inner cavity. The flexible rolling diaphragm 830 is fixed and sealed to the shell-shaped base 810. The flexible rolling diaphragm 830 is located between the second inner cavity 811 and the first inner cavity, and is in direct contact with the insulating oil filled in the first inner cavity. The elastic element 820 is installed in the second inner cavity 811. The elastic element 820 is fixedly connected to the shell-like base 810 and is in contact or connection with the flexible rolling diaphragm 830. The flexible rolling diaphragm 830 can be deformed toward the first inner cavity or the second inner cavity 811 under the action of external force. The external force is the combined force of the elastic force of the elastic element 820, the pressure of the insulating oil filled in the first inner cavity, and the ambient pressure in the second inner cavity 811. It can be understood that the shell-shaped base 810 of the pressure compensation mechanism 800 is a cylindrical structure with one end open, and the flexible rolling diaphragm 830 covers the open port of the shell-shaped base 810. Therefore, the second inner cavity 811 can also be understood as being formed by the shell-shaped base 810 and the flexible rolling diaphragm 830. Alternatively, it can be understood that the shell-shaped base 810 is a cylindrical structure, and one end of the shell-shaped base 810 has a window connected to the first inner cavity, and the flexible rolling diaphragm 830 is fixed and sealed to the shell-shaped base 810 and covers the window. In short, one side of the surfaces of the flexible rolling diaphragm 830 facing away from the two sides directly faces the first inner cavity, and the other side surface directly faces the second inner cavity 811.

[0054] It can be understood that the second inner cavity 811 inside the pressure compensation mechanism 800 is directly connected to the external environment. When the low-vibration propulsion motor dives with the underwater vehicle, water in the external environment (such as seawater) will enter the second inner cavity 811. At this time, the ambient pressure in the second inner cavity 811 is the pressure of the entering water.

[0055] Specifically, the pressure compensation mechanism 800 maintains the pressure difference between the propulsion motor and the external environment through the elastic force of the elastic element 820, that is, through the interaction between the elastic element 820 and the pressure of the insulating oil filled in the first inner cavity and the ambient pressure in the second inner cavity 811, the dynamic balance of the pressure inside the propulsion motor is achieved, thereby ensuring the stability of the movement of the elastic element 820, thereby maintaining the internal and external pressure difference of the propulsion motor, which can reduce vibration and make the pressure of the insulating oil inside the propulsion motor act on each part, which is equivalent to applying a force to each part. This force is equivalent to applying an elastic constraint to each part, which can have a vibration reduction effect.

[0056] Specifically, the axial direction of the elastic element 820 and the second inner cavity 811 is parallel to the axial direction of the rotating shaft. The elastic element 820, the second inner cavity 811, the rotating shaft, the motor housing 100, and the first inner cavity are preferably coaxially arranged, wherein one end of the elastic element 820 is fixedly connected to the shell-shaped base 810, and the other end is connected to the flexible rolling diaphragm 830.

[0057] As a preferred solution, the aspect ratio of the elastic element 820 is , the pressure compensation mechanism 800 satisfies: ; Where m is the mass of elastic element 820, c is the damping of elastic element 820, t is the duration of deformation of elastic element 820, A is the effective pressure-bearing area of ​​pressure compensation mechanism 800, P is the pressure of insulating oil, k is the stiffness of elastic element 820, and x is the deformation of elastic element 820. It should be noted that the effective pressure-bearing area of ​​pressure compensation mechanism 800 is the overlapping area between flexible rolling diaphragm 830 and second inner cavity 811.

[0058] In a preferred embodiment, to improve the stability of the movement of the elastic element 820 and enhance the reliability of the pressure compensation mechanism 800, the pressure compensation mechanism 800 further includes a guide post 840. The guide post 840 is fixedly disposed in the second inner cavity 811. The elastic element 820 is sleeved on the guide post 840. The elastic element 820 is constrained to elastically expand and contract along the axial direction of the guide post 840. Preferably, the axial direction of the guide post 840 is parallel to the axial direction of the elastic element 820. More preferably, the guide post 840 and the elastic element 820 are coaxial. For example, the elastic element 820 may be a spring, etc., which may be directly connected to the flexible rolling diaphragm 830 or connected via an intermediate connecting gasket, etc. The specific material and characteristic parameters of the flexible rolling diaphragm 830 are not limited herein as long as it can deform under a specified pressure differential and compress the insulating oil in the first inner cavity.

[0059] Specifically, the motor housing 100 is provided with one or more seawater inlet holes 111, which communicate with the second inner cavity 811. Seawater from the external environment can flow freely between the external environment and the second inner cavity 811 through the seawater inlet holes 111. More specifically, the seawater inlet holes 111 are provided on the front flange 110 of the electrical housing, and a seawater inlet channel may also be provided within the front flange 110. The seawater inlet channel communicates with the seawater inlet holes 111 and the second inner cavity 811, respectively, and is sealed and isolated from the first inner cavity.

[0060] By utilizing the seawater inlet hole 111 provided on the motor housing 100 to fill the interior of the pressure compensation mechanism 800 with seawater, not only can the overall volume of the propulsion motor be effectively reduced, thereby reducing the weight of the oil filling and the overall weight of the propulsion motor, but also a pressure difference can be formed between the interior of the pressure compensation mechanism 800 and the interior of the propulsion motor.

[0061] Specifically, the interior of the rotating shaft in this application is hollow, and the pressure compensation mechanism 800 is entirely disposed within the rotating shaft. More specifically, one end of the shell-shaped base 810 of the pressure compensation mechanism 800 is fixedly connected to the front flange 110. The shell-shaped base 810 of the pressure compensation mechanism 800 can be entirely or substantially disposed within the rotating shaft. Furthermore, none of the components of the pressure compensation mechanism 800, including the shell-shaped base 810, directly contact the rotating shaft, thus not affecting the operation of the rotating shaft. However, it should be emphasized that the gap between the pressure compensation mechanism 800 and the rotating shaft is connected to the first inner cavity and can be directly considered as part of the first inner cavity. Therefore, the gap between the pressure compensation mechanism 800 and the rotating shaft is also filled with insulating oil. This design not only enables the introduction of the pressure compensation mechanism 800 without changing the external volume of the motor housing 100, but also reduces the volume of the internal cavity of the electrical connection housing, improving overall space utilization and reducing the volume / amount of insulating oil required.

[0062] This application provides a pressure compensation mechanism 800 within the propulsion motor and utilizes the aforementioned seawater inlet hole 111 to introduce seawater into the pressure compensation mechanism 800, filling the pressure compensation mechanism 800 with seawater. This creates a pressure difference between the pressure compensation mechanism 800 and the propulsion motor, achieving a pressure compensation effect. This also effectively reduces the volume of the propulsion motor, thereby reducing the weight of the oil filling and overall weight reduction of the propulsion motor. Furthermore, compared to the method of only filling the propulsion motor with high-voltage insulating oil, the method of this embodiment not only eliminates the need to thicken the motor housing 100 to improve its pressure-bearing capacity, but also allows the motor housing 100 to be appropriately thinned, contributing to the lightweighting of the propulsion motor.

[0063] As a preferred embodiment, the outer wall of the motor housing 100 is provided with multiple seawater flow channels, which continuously extend axially across the outer wall of the motor housing 100. Specifically, the seawater flow channels can be grooves arranged along the outer wall of the motor housing 100 and extending continuously in the axial direction. The multiple seawater flow channels are sequentially arranged along the axial direction of the motor housing 100. This design of integrated axial seawater flow channels in the motor housing 100 allows for forced convection of external water along the propulsion direction during propulsion motor operation, significantly improving heat dissipation and reducing propulsion resistance.

[0064] It should be noted that the seawater flow channel can be provided only on the motor housing body 120, or on the motor housing body 120 and the surfaces of the front and rear flanges 130. The specific width and depth of the seawater flow channel can be set according to specific circumstances and are not limited here.

[0065] Furthermore, the propulsion motor in this application can utilize O-ring seals at the mating points of the stationary components. The compression and extension of the O-rings are calculated to achieve optimal sealing performance, as is known in the art and not specifically limited herein. Specifically, the stator and flange are clearance-matched, with two O-rings positioned between the two components to create a two-stage seal. This gradually reduces seawater pressure and effectively enhances the stator's sealing performance.

[0066] In this propulsion motor, the rotating components are sealed with a stable mechanical dynamic seal, ensuring the overall sealing of the propulsion motor. A mechanical dynamic seal is used between the stator and rotor of the propulsion motor for rotary sealing. This mechanical dynamic seal shifts the sealing area to the well-controlled surfaces of the static and dynamic rings. The dynamic ring, pushed by a spring, creates a pressure differential with the static ring that is greater than the external pressure, achieving a rotary seal for the propulsion motor.

[0067] Before the propulsion motor in the present application is launched into the water with the underwater vehicle, the first cavity in the motor housing 100 is filled with insulating oil. As the insulating oil rushes in, the internal pressure will increase, and the increased pressure will force the elastic element 820 of the pressure compensation mechanism 800 to compress and deform until the elastic element 820 reaches a certain deformation amount. At this time, the injection of insulating oil is stopped and the oil filling port is closed. A certain pressure is maintained in the first cavity in the motor housing 100. The pressure of the insulating oil is uniformly applied to each part in contact with the insulating oil in the motor housing 100, and a certain pressure difference between the inside and the outside is maintained. At this time, the propulsion motor can be launched into the water and run. Even if the propulsion motor has some oil leakage at the mechanical dynamic sealing structure 600, the elastic element 820 of the pressure compensation mechanism 800 will maintain the pressure difference between the inside and the outside of the propulsion motor, thereby ensuring the sealing of the propulsion motor.

[0068] Specifically, in the initial state, the pressure of the insulating oil injected into the first inner cavity is typically around 1-2 MPa. At this point, the elastic element will elastically deform. However, the underwater vehicle will eventually dive to a pressure of several tens of MPa. The initial injection of insulating oil prevents seawater from entering the propulsion motor through the mechanical dynamic seal structure 600, ensuring the stability of the propulsion motor. If the initial pressure is 1 MPa, the pressure differential between the propulsion motor and the outside world will remain stable at 1 MPa during the dive. If the insulating oil leaks, the elastic element will also expand, maintaining the pressure differential between the inside and outside of the propulsion motor.

[0069] The present application embeds the pressure compensation mechanism in the propulsion motor and injects insulating oil with a certain pressure into the propulsion motor, forcing the elastic element in the pressure compensation mechanism to maintain a certain deformation, thereby enabling the propulsion motor to maintain a certain pressure and maintain a certain pressure difference between the inside and the outside. In particular, the internal and external pressure difference generated by the pressure compensation mechanism on the propulsion motor is smaller than the specific pressure generated by the mechanical dynamic sealing structure, thereby effectively ensuring the sealing of the propulsion motor at different diving depths and reducing or eliminating the leakage of the insulating oil medium.

[0070] This application provides a pressure compensation mechanism within the propulsion motor and utilizes the aforementioned seawater inlet hole to introduce seawater into the pressure compensation mechanism, filling it with seawater. This creates a pressure difference between the interior of the pressure compensation mechanism and the interior of the propulsion motor, achieving a pressure compensation effect. This also effectively reduces the volume of the propulsion motor, thereby reducing the weight of the oil filling and, overall, the weight of the propulsion motor. Furthermore, compared to the method of filling the propulsion motor with high-voltage insulating oil, the method of this embodiment not only eliminates the need to thicken the motor casing to increase its pressure-bearing capacity, but also allows the motor casing to be appropriately thinned, contributing to the lightweighting of the propulsion motor.

[0071] This application sets up multiple seawater flow channels on the outer wall of the motor housing and adopts the design of integrated axial seawater flow channels in the motor housing. When the propulsion motor is working, the external water flow can be forced to convect along the propulsion direction, which significantly improves the heat dissipation coefficient and reduces the propulsion resistance.

[0072] The low-vibration propulsion motor of the present application has the advantages of low vibration and low noise. In particular, by adopting an embedded pressure compensation mechanism, it can significantly reduce the size of the motor, reduce its own weight, improve its thrust-to-weight ratio, and make it adaptable to different diving depths. It can operate stably in deep water for a long time, while improving its overall heat dissipation performance and improving its working stability.

[0073] The above embodiments are intended only to illustrate the technical concepts and effects of this application, with the goal of enabling those familiar with this technical field to understand the content of this application and implement it accordingly. However, these embodiments do not constitute a limitation on the scope of protection of this application. Any equivalent transformations or modifications made based on the spirit and technical ideas of this application should be covered by the claims of this application.

Claims

1. A low-vibration propulsion motor with an embedded pressure compensation mechanism, comprising a motor housing and a stator, a rotor, and a rotating shaft mounted in a first inner cavity within the motor housing, the rotating shaft being connected to the rotor, the rotating shaft being rotationally engaged with the motor housing via a bearing, and being rotationally and sealingly engaged with the motor housing via a mechanical dynamic seal structure, the first inner cavity being isolated from the external environment at least via the mechanical dynamic seal structure, and the first inner cavity being further filled with insulating oil having a set pressure, the insulating oil filling the first inner cavity; Its characteristics are: The propulsion motor also includes a pressure compensation mechanism fixedly arranged in the motor housing, the pressure compensation mechanism including a shell-shaped base having a second inner cavity, an elastic element and a flexible rolling diaphragm, the second inner cavity is connected to the external environment and is sealed and isolated from the first inner cavity, the flexible rolling diaphragm is fixed and sealed to the shell-shaped base, the flexible rolling diaphragm is between the second inner cavity and the first inner cavity, and is in direct contact with the insulating oil filled in the first inner cavity, the elastic element is installed in the second inner cavity, the elastic element is fixedly connected to the shell-shaped base, and is in contact or connection with the flexible rolling diaphragm, and the flexible rolling diaphragm can produce deformation toward the first inner cavity or the second inner cavity under the action of external force, and the external force is the combined force of the elastic force of the elastic element, the pressure of the insulating oil filled in the first inner cavity, and the ambient pressure in the second inner cavity.

2. The low-vibration propulsion motor with a built-in pressure compensation mechanism according to claim 1, characterized in that: The axial directions of the elastic element and the second inner cavity are parallel to the axial direction of the rotating shaft; one end of the elastic element is fixedly connected to the shell-shaped base, and the other end is connected to the flexible rolling diaphragm; and / or, the aspect ratio of the elastic element , the pressure compensation mechanism satisfies: ; Where m is the mass of the elastic element, c is the damping of the elastic element, t is the duration of deformation of the elastic element, A is the effective pressure-bearing area of ​​the pressure compensation mechanism, P is the pressure of the insulating oil, k is the stiffness of the elastic element, and x is the deformation of the elastic element.

3. The low-vibration propulsion motor with a built-in pressure compensation mechanism according to claim 1 or 2, characterized in that: The pressure compensation mechanism further includes a guide post, the guide post being fixedly disposed in the second inner cavity, the elastic element being sleeved on the guide post, and the elastic element being restricted to elastically expand and contract along the axial direction of the guide post; And / or, the axial direction of the guide pillar is parallel to the axial direction of the elastic element.

4. The low-vibration propulsion motor with a built-in pressure compensation mechanism according to claim 1 or 2, characterized in that: The motor housing is provided with one or more seawater introduction holes, which are communicated with the second inner cavity. Seawater in the external environment can flow freely between the external environment and the second inner cavity through the seawater introduction holes.

5. The low-vibration propulsion motor with a built-in pressure compensation mechanism according to claim 4, characterized in that: The motor housing includes a front flange, a motor housing body, and a rear flange connected in sequence along the axial direction; the stator is fixedly matched with the motor housing body; the rotating shaft is rotatably matched with the front flange and the rear flange via the two bearings respectively; the mechanical dynamic seal structure is provided between the rear flange and the rotating shaft; the pressure compensation mechanism is fixedly connected to the front flange; the interior of the rotating shaft is hollow; the pressure compensation mechanism is entirely provided inside the rotating shaft; there is no direct contact between the pressure compensation mechanism and the rotating shaft; the gap between the pressure compensation mechanism and the rotating shaft is connected to the first inner cavity; and the seawater introduction hole is provided on the front flange; And / or, a seawater introduction channel is provided in the front flange, the seawater introduction channel is communicated with the seawater introduction hole and the second inner cavity respectively, and the seawater introduction channel is sealed and isolated from the first inner cavity.

6. The low-vibration propulsion motor with a built-in pressure compensation mechanism according to claim 5, characterized in that: The gap between the stator and the rotor, and the gap between the rotating shaft and the bearing are directly connected to the first inner cavity. The insulating oil medium also fills the gap between the stator and the rotor, the gap between the rotating shaft and the sliding bearing, and the gap between the bearings, and forms a pressure-bearing oil film in the gap between the stator and the rotor, the gap between the rotating shaft and the bearing, and the gap between the bearings. And / or, the bearing comprises a sliding bearing having a tubular structure, wherein one end of the tubular structure close to the rotor extends radially outward to form an annular protrusion; And / or, the sliding bearing is an L-shaped tubular structure; And / or, the pressure-bearing oil film between the sliding bearing and the rotating shaft is a wedge-shaped oil film structure, and when the rotor rotates, the pressure of the wedge-shaped oil film structure increases as the speed of the rotor increases; And / or, the gap between the sliding bearing and the rotating shaft is an annular gap, the width of the annular gap is D / 1000 to 2D / 1000, where D is the outer diameter of the sliding bearing; And / or, the bearing is further provided with an oil hole penetrating the bearing, the oil hole is communicated with the first inner cavity, and the insulating oil is also filled in the oil hole.

7. The low-vibration propulsion motor with a built-in pressure compensation mechanism according to claim 5, characterized in that: A resolver encoder is also provided in the rear flange, and the resolver encoder is used to monitor the working status of the propulsion motor. The resolver encoder and the rotor have the same number of pole pairs; And / or, the front end of the low-vibration propulsion motor is further sealed with a watertight connector, and a power line groove is opened on the inner wall of the motor housing, and the power line passes through the power line groove to electrically connect the power terminal of the watertight connector with the stator and / or rotor; And / or, the watertight connector is sealed to the front flange.

8. The low-vibration propulsion motor with a built-in pressure compensation mechanism according to claim 1 or 5, characterized in that: The rotating shaft includes a first shaft segment and a second shaft segment fixedly connected along the axial direction, the first shaft segment is composed of a magnetic metal material and serves as a rotor core, the second shaft segment is composed of a corrosion-resistant material, the first shaft segment is entirely arranged in the motor housing, and the second shaft segment is partially arranged outside the motor housing.

9. The low-vibration propulsion motor with a built-in pressure compensation mechanism according to claim 1, characterized in that: A plurality of seawater flow channels are provided on the outer wall of the motor housing, and the seawater flow channels continuously cross the outer wall of the motor housing in the axial direction; And / or, the seawater flow channel includes a groove structure provided on the outer wall of the motor housing and extending continuously in the axial direction.

10. An underwater vehicle, characterized in that: A low-vibration propulsion motor comprising the built-in pressure compensation mechanism according to any one of claims 1 to 9.

Images