Electric motor with intrinsic cooling system

Abstract

The present disclosure relates to an electric motor comprising: a stator (101) which is a fixed part in the electric motor, the stator (101) having a plurality of poles installed in a radial direction; a rotor (102) having a plurality of magnets and disposed to freely rotate around the stator (101), the stator (101) and the rotor (102) being molded into an epoxy layer of a housing of the motor such that a passage (106) is formed, thereby allowing a cooling medium to flow through an inner portion of the electric motor.

Description

Technical Field

[0001] This disclosure generally relates to the field of electric motors. In particular, this disclosure relates to a system for cooling an electric motor (specifically, a motor with the rotor located on the outside). Background Technology

[0002] In recent years, there has been a growing trend of using electric motors in various applications, such as electric vehicles, drones, boats, pumps, etc. There are many different types of electric motors; some examples are synchronous or asynchronous motors, DC or AC motors, brushed or brushless motors, inrunner motors or outrunner motors.

[0003] Generally speaking, an electric motor is a motor that converts electrical energy into mechanical energy in the form of rotation. An electric motor operates through the interaction between the motor's magnetic field and the electromagnetic field generated by inductive windings. The result of this interaction is a rotating electromagnetic field, which in turn produces a rotational force (so-called torque), for example, in the form of rotating a shaft.

[0004] There are many types of motors on the market, but in this disclosure we focus primarily on electric brushless DC motors with the rotor located on the outside (so-called external rotor motors).

[0005] An external rotary motor typically consists of a stator and a rotor, where the stator has windings or poles located at the center of the motor, and the rotor has permanent magnets adapted to rotate around the stator. This configuration usually has a larger diameter than other types of electric motors and allows for more windings, poles, or magnets to be placed in the rotor, thereby increasing the rotating magnetic field.

[0006] Furthermore, for motors, a larger diameter results in a larger circumference per revolution. A larger diameter also indicates a larger torque arm for externally driven motors, and therefore higher torque. For externally driven motors, a larger torque arm can provide higher torque at the same speed.

[0007] A known problem with external rotary motors is that heat from the stator poles is transferred to the center of the motor, causing overheating and limiting the maximum power that can be applied to the motor. Furthermore, excessive heat weakens the magnets and damages the insulation of the windings or poles, thus severely limiting the applications that can be implemented with external rotary motors. Summary of the Invention

[0008] The purpose of this disclosure is to alleviate, mitigate or eliminate the defects and disadvantages of one or more of the prior art as described above, and at least to solve the aforementioned problems.

[0009] According to a first aspect, an electric motor is provided, comprising: a housing having a fixed internal portion and a rotatable external portion; a stator mounted on the fixed internal portion of the housing; and a rotor attached to the rotatable external portion of the housing, the rotor being configured to rotate freely about the stator; the electric motor is characterized in that the rotatable external portion has at least one inlet configured to receive a cooling medium and at least one outlet configured to discharge a cooling medium; the stator and rotor are each molded in a respective epoxy layer; and a channel is provided between the molded rotor and the molded stator to guide the cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor.

[0010] The epoxy layer protects the stator and rotor from any liquids that leak into the circuitry. This is achieved by molding the stator into one epoxy layer and the rotor into another, thus eliminating the need for additional seals afterwards.

[0011] The passage or channel between the stator and rotor allows cooling medium to pass through, thereby reducing the temperature of the rotor's internal portion facing the stator.

[0012] The use of an electric motor capable of achieving high torque in conjunction with an internal cooling system according to this disclosure provides an electric motor that does not require a gearbox and is far more efficient than previous versions of electric motors, resulting in a higher energy density than previous motor designs.

[0013] Furthermore, no additional seals are required, which provides robustness to the motor and reduces standard wear parts.

[0014] Furthermore, the channel is configured to allow cooling medium to flow through the electric motor and to be in fluid communication with at least one inlet and at least one outlet, wherein at least one inlet is adapted to introduce cooling medium into the channel and at least one outlet is adapted to discharge cooling medium from the channel by centrifugal force during rotor rotation.

[0015] In addition, at least one outlet can discharge the cooling medium by means of the centrifugal force generated during rotor rotation.

[0016] Since the rotor is located on the outer part of the housing, the cooling medium can be discharged through at least one outlet provided on the outer part of the housing when the rotor rotates. Thus, when the electric motor is operating, rotational force or centrifugal force can be used to discharge the cooling medium from the outlet. As a result, the cooling medium moves continuously from at least one inlet to at least one outlet, so that the cooling medium is always kept at a low temperature.

[0017] According to some embodiments, the motor may also include an additional channel. This additional channel may be arranged to allow cooling medium to flow through the motor. The additional channel may, for example, extend axially through the center of the motor. The additional channel may, for example, extend axially through the center of a fixed internal portion of the housing. By providing the additional channel, cooling medium can flow through the motor.

[0018] According to some embodiments, the electric motor may include at least one outlet, which may be disposed on an external portion of the housing and adapted to discharge cooling medium from the channel by centrifugal force during rotor rotation.

[0019] According to some embodiments, an electric motor may include a housing, a stator, a rotor, a channel, and at least one outlet. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. A channel may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor. The at least one outlet may be located on the external portion of the housing and is adapted to discharge cooling medium from the channel by centrifugal force during rotor rotation.

[0020] According to some embodiments, at least one inlet may be arranged on the inner surface of the fixed internal portion. By arranging at least one inlet on the inner surface of the fixed internal portion, the flow of the cooling medium through the channel can be improved. For example, the cooling medium can be propelled toward the at least one inlet by the centrifugal force or rotational force generated during rotor rotation. Furthermore, the discharge of cooling medium from at least one outlet via the channel can create suction at the at least one inlet. According to some embodiments, at least one inlet may be arranged on the stator toward an additional channel. By arranging at least one inlet on the inner surface of the fixed internal portion, the flow of the cooling medium through the channel can be improved. For example, the cooling medium can be propelled from the additional channel toward the at least one inlet by the centrifugal force or rotational force generated during rotor rotation. Furthermore, the discharge of cooling medium from at least one outlet via the channel can create suction at the at least one inlet.

[0021] According to some embodiments, at least one inlet may be provided with a fluid guiding device (such as an extension located at the edge of the inlet) to guide the flowing cooling medium to the inlet. The extension may be located on a portion of the inlet that is downstream or rearward in relation to the flow of the cooling medium. The extension may also have a concave surface to further guide the flow of the cooling medium toward the inlet.

[0022] According to some embodiments, at least one inlet may be provided with a fluid guiding device (such as a recess located at the edge of the inlet) to guide the flowing cooling medium to the inlet. The recess may be located on a portion of the inlet that is upstream or forward in relation to the flow of the cooling medium. The extension may also have a concave surface to further guide the flow of the cooling medium toward the inlet.

[0023] According to some embodiments, the location of the fluid guiding device can be determined based on the flow direction of the cooling medium during motor operation. According to some embodiments, the additional channel can be a central channel and / or a motor channel, or can be referred to as a central channel and / or a motor channel.

[0024] According to some embodiments, an electric motor may include a housing, a stator, a rotor, and a channel. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. The channel may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor.

[0025] In addition, the internal cooling system may include an additional channel that extends axially through the center of a fixed internal portion of the housing and is arranged to allow the cooling medium to flow through it.

[0026] In addition, some of the outlets can be arranged around the periphery of the rotatable outer part of the shell.

[0027] When the outlets are arranged around the periphery of the outer portion of the casing, the cooling medium is discharged in a manner that disperses around the surface of the outer portion.

[0028] In addition, the rotatable outer portion of the shell is at least partially cylindrical.

[0029] The partially cylindrical shape allows the cooling medium to flow in the axial direction, thereby cooling most of the internal motor.

[0030] Furthermore, the outlet can be any of a circular opening, a slit, or a conical opening. This shape depends on, for example, the thickness of the cooling medium or the position of the magnets within the rotor. This flexibility in the construction of the electric motor provides optimal efficiency.

[0031] According to some embodiments, the epoxy layer may be at least partially electrically insulating. For example, the electrical insulation properties of an at least partially electrically insulating epoxy layer may be greater than 100 ohms per mm of thickness. The electrical insulation properties of an electrically insulating epoxy layer may also be greater than 1 kiloohm per mm of thickness, 10 kiloohms per mm of thickness, 100 kiloohms per mm of thickness, 1 megaohm per mm of thickness, 10 megaohms per mm of thickness, 100 megaohms per mm of thickness, 1000 megaohms per mm of thickness, or 10000 megaohms per mm of thickness.

[0032] According to some embodiments, the epoxy layer can be electrically insulating. For example, the electrical insulation properties of an electrically insulating epoxy layer can be greater than 100 ohms per mm of thickness. The electrical insulation properties of an electrically insulating epoxy layer can also be greater than 1 kiloohm per mm of thickness, 10 kiloohms per mm of thickness, 100 kiloohms per mm of thickness, 1 megaohm per mm of thickness, 10 megaohms per mm of thickness, 100 megaohms per mm of thickness, 1000 megaohms per mm of thickness, or 10000 megaohms per mm of thickness.

[0033] According to some embodiments, the epoxy layer may be at least partially thermally conductive. For example, the thermal conductivity of a partially thermally conductive epoxy layer may be greater than 0.5 watts per millikelvin (W / mK). The thermal conductivity of a thermally conductive epoxy layer may also be 1 W / mK.

[0034] According to some embodiments, the epoxy layer can be thermally conductive. For example, the thermal conductivity of a thermally conductive epoxy layer can be greater than 0.5 watts per millikelvin (W / mK). The thermal conductivity of a thermally conductive epoxy layer can also be 1 W / mK.

[0035] According to some embodiments, the epoxy layer may be at least partially thermally conductive and at least partially electrically insulating. For example, the electrical insulation property of an at least partially electrically insulating epoxy layer may be greater than 100 ohms per mm of thickness. The electrical insulation property of an electrically insulating epoxy layer may also be greater than 1 kiloohm per mm of thickness, 10 kiloohms per mm of thickness, 100 kiloohms per mm of thickness, 1 megaohm per mm of thickness, 10 megaohms per mm of thickness, 100 megaohms per mm of thickness, 1000 megaohms per mm of thickness, or 10000 megaohms per mm of thickness. For example, the thermal conductivity of an at least partially thermally conductive epoxy layer may be greater than 0.5 watts per millikelvin (W / mK). The thermal conductivity of a thermally conductive epoxy layer may also be 1 W / mK.

[0036] According to some embodiments, the epoxy layer can be thermally conductive and electrically insulating. For example, the electrical insulation property of an electrically insulating epoxy layer can be greater than 100 ohms per mm of thickness. The electrical insulation property of an electrically insulating epoxy layer can also be greater than 1 kiloohm per mm of thickness, 10 kiloohms per mm of thickness, 100 kiloohms per mm of thickness, 1 megaohm per mm of thickness, 10 megaohms per mm of thickness, 100 megaohms per mm of thickness, 1000 megaohms per mm of thickness, or 10000 megaohms per mm of thickness. For example, the thermal conductivity of a thermally conductive epoxy layer can be greater than 0.5 watts per millikelvin (W / mK). The thermal conductivity of a thermally conductive epoxy layer can also be 1 W / mK. According to some embodiments, the epoxy layer can have a low viscosity, for example, a viscosity in the range of 1400 to 2200 cPs at 23 degrees Celsius and 100 rpm. The epoxy layer can also be homogeneous and / or thermally stable.

[0037] According to some embodiments, the epoxy layer can be cured at room temperature.

[0038] According to some embodiments, an electric motor may include a housing, a stator, a rotor, and channels. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. Channels may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor. The epoxy layer may be thermally conductive and electrically insulating.

[0039] In addition, the electric motor is configured to operate in an immersion state and the cooling medium is water.

[0040] The advantage of setting the motor to operate in an submerged state is that it can be used in naval or marine applications such as submarines, ships, and pumps. Furthermore, no additional container with a cooling medium is required, thus facilitating the operation of the electric motor.

[0041] According to some embodiments, multiple magnets of the rotor can be arranged in a magnetization pattern that concentrates the combined magnetic flux of these magnets to the center of the rotor. The rotor can be hollow, for example, having a cylindrical shape, so that the magnetic flux can be concentrated in the hollow central portion of the cylindrical rotor. This hollow central portion may include other components.

[0042] According to some embodiments, the multiple magnets of the rotor can be arranged in a Heilbeck configuration, thereby directing the magnetic field strength toward the center of the rotor. By directing the magnetic field, a more efficient and / or more compact arrangement of the magnets can be achieved, thereby maximizing the size of the cooling fluid passage between the stator and rotor without reducing motor efficiency. The rotor can be hollow, for example, having a cylindrical shape, so that the magnetic flux can be concentrated in the hollow central portion of the cylindrical rotor. The hollow central portion may include other components.

[0043] According to some embodiments, the magnet may include a high-throughput alloy, such as neodymium steel.

[0044] According to some embodiments, magnets arranged in a Heilbeck configuration can be arranged in a spatially rotating magnetization pattern to enhance the magnetic field on one side of the configuration while canceling the magnetic field on the other side of the configuration to bring it close to zero.

[0045] According to some embodiments, an electric motor may include a housing, a stator, a rotor, and a channel. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotor may include magnets arranged in a Helbeck configuration. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. The channel may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor.

[0046] According to some embodiments, the motor may also include at least one thruster. This at least one thruster may be arranged on and / or connected to a rotatable portion of the motor (such as a rotor). Thus, the rotational force generated on the rotor by the electric motor can be converted into thrust through the rotational movement of the rotor and the thruster.

[0047] According to some embodiments, the motor may also include a thruster connector, wherein the thruster connector is configured to connect to at least one thruster.

[0048] According to some embodiments, the propulsion unit may include a hub and a plurality of radial blades arranged in a pitch to form a helical pattern, thereby converting rotational power into linear thrust by acting on a working fluid (such as water) during rotation.

[0049] According to some embodiments, the propulsion device can be a propeller.

[0050] According to some embodiments, the thruster can be arranged to operate while submerged in water.

[0051] According to some embodiments, the motor may also include an impeller.

[0052] According to some embodiments, an electric motor may include a housing, a stator, a rotor, channels, and a propeller. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. Channels may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor. A propeller may be arranged on the rotor, and the epoxy layer may be thermally conductive and electrically insulating.

[0053] According to some embodiments, an electric motor may include a housing, a stator, a rotor, a channel, and a propeller. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. A channel may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor. A propeller may be arranged on the rotor.

[0054] According to some embodiments, the motor may include a second housing and be configured for jetting. The second housing may be arranged to at least partially surround the motor and the propeller, thereby creating a surrounding channel between the second housing and the rotor, in which the propeller may interact with fluid.

[0055] According to some embodiments, the motor may include a rotor located within a hollow stator and a thruster located within the hollow rotor. This arrangement allows the thruster to interact with fluid transported within an additional channel. By protecting the thruster located inside the motor, a more durable motor can be provided.

[0056] According to some embodiments, the motor may have a rotor located within a hollow stator and a thruster located within the hollow rotor. With this arrangement, the motor can drive the thruster from a position surrounding it. Compared to driving in a central position, this arrangement allows for a easier construction of the jet configuration by providing drive to the motor closer to the housing.

[0057] According to some embodiments, the motor may include a second housing and be configured for jetting. The second housing may be arranged to at least partially surround the motor and the propeller, thereby creating a surrounding channel between the second housing and the rotor, in which the propeller may interact with fluid.

[0058] According to some embodiments, an electric motor is provided for powering an underwater vehicle. The vehicle may be, for example, a boat, motorboat, ship, submarine, etc. The motor can provide power through a propeller and operate while submerged. This motor has been described in any of the embodiments disclosed herein.

[0059] According to some embodiments, the electric motor can be configured as an external engine, an internal engine, or a pod.

[0060] According to some embodiments, the electric motor may also include mounting devices adapted for mounting the motor to a vessel. For example, the motor may be mounted on a beam, stern, hull, rudder, and / or hydrofoil.

[0061] According to some embodiments, the electric motor can be configured to be mounted on, for example, a beam, stern, hull, rudder, and / or hydrofoil.

[0062] The present invention will become apparent from the specific embodiments given below. The specific embodiments and examples disclosed are merely illustrative of preferred embodiments of the invention. Those skilled in the art will understand, through the guidance of the specific embodiments, that changes and modifications can be made within the scope of the invention.

[0063] Therefore, it should be understood that the invention disclosed herein is not limited to the specific components of the described apparatus or the steps of the described methods, as these apparatuses and methods can vary. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. It should be noted that, as used in the specification and appended claims, the articles “a,” “an,” “the,” and “the” are intended to indicate the presence of one or more elements, unless the context clearly specifies otherwise. Thus, for example, references to “a unit” or “the unit” may include several devices, etc. Furthermore, the words “comprising,” “including,” “containing,” and similar terms do not exclude other elements or steps.

[0064] In terms of terminology, the term "channel" should be interpreted as a gap, passage, or space that transports fluid from a starting position to an ending position. Attached Figure Description

[0065] The foregoing objects, as well as other objects, features, and advantages of this disclosure, will be more fully understood by referring to the following illustrative and non-limiting detailed description of exemplary embodiments of the invention, taken in conjunction with the accompanying drawings.

[0066] Figure 1 A cross-sectional view of an electric motor according to an example of this disclosure is shown.

[0067] Figure 1b A schematic cross-sectional view of an electric motor according to an example of this disclosure is shown.

[0068] Figure 1c A schematic cross-sectional view of an entry point according to an example of this disclosure is shown.

[0069] Figure 1d A schematic screenshot of an entry point according to an example of this disclosure is shown.

[0070] Figure 2A An exploded view of the rotatable outer portion of the housing of an example electric motor according to this disclosure is shown.

[0071] Figure 2B A perspective view of the rotatable external portion of the housing of an example electric motor according to the present disclosure is shown.

[0072] Figure 2C A perspective view of the fixed internal portion of the housing of an example electric motor according to the present disclosure is shown.

[0073] Figure 3A and Figure 3B A perspective view of an example embodiment of an electric motor according to the present disclosure is shown. Detailed Implementation

[0074] The invention will now be described with reference to the accompanying drawings, in which preferred exemplary embodiments of the invention are shown. However, the invention may be embodied in other forms and should not be construed as limited to the embodiments disclosed herein. The disclosed embodiments are provided to fully convey the scope of the invention to those skilled in the art.

[0075] Figure 1A cross-sectional view of an example electric motor according to an embodiment of the present invention is shown. The electric motor includes a housing 100 made of a non-oxidizable material and having a rotatable outer portion 120, which is at least partially cylindrical. However, different variations of this shape are also possible. For example, a partially cylindrical shape with tapered or rounded ends is also considered a feasible option.

[0076] The housing 100 has a fixed internal portion 110 and a rotatable external portion 120, and the housing includes a stator 101 supported by the fixed internal portion 110 and a rotor 102 attached to the rotatable external portion 120. The rotor is configured to rotate freely about the stator 101.

[0077] The stator 101, supported by a fixed internal portion 110, includes a stator core having a plurality of poles arranged radially, and windings or conductors mounted on each pole. A rotatable external portion 120 of the housing houses a rotor 102 containing a plurality of permanent magnets. The rotor 102 is also attached to the stator 101 at both ends of the housing 100 by ball bearings 103A, 103B, or any similar elements to allow free rotation about the stator and to provide a channel 106 between the stator and rotor. The size of the channel 106 can vary depending on the desired effect. For a highly efficient electric motor, the electromagnetic field in the channel 106 between the rotor and stator needs to be as small as possible. Simultaneously, if the channel 106 is as large as possible, the cooling system will be more efficient. Therefore, balancing these two constraints yields the optimal approach to achieving a highly efficient electric motor.

[0078] When the stator and rotor 102 operate together and are powered by DC, the current in the poles interacts with the magnetic field generated by the multiple magnets of the rotor 102, thereby generating a rotational force or torque that rotates the rotor. Depending on the application of the electric motor, the motor can be attached to a propeller shaft or any other rotatable shaft.

[0079] like Figure 1 As shown by the dashed lines, the stator 101 and rotor 102 are each molded within corresponding epoxy layers 107A and 107B. In other words, the stator is encapsulated or molded in epoxy layer 107A, which prevents and protects the stator from damage caused by any cooling medium (such as water). However, it does not necessarily have to be an epoxy layer, but any other layer that protects the stator and rotor from damage caused, for example, by water and dust ingress, such as a plastic or resin layer.

[0080] Similar to the stator 101, the rotor 102 is also encapsulated or molded into an epoxy layer 107B to prevent any moisture, rust, dust, cooling medium, or water from entering the internal parts of the rotor. The rotor 102 and stator 101 are encapsulated in separate epoxy layers such that the channel 106 between the rotor 102 and stator 101 is isolated and sealed relative to the internal parts of the stator and rotor. This isolation or sealing allows cooling media such as water to flow through the channel 106 through at least one inlet 104A, 104B and at least one outlet 105A, 105B. Figure 1 An exemplary embodiment shows a rotatable external portion 100 having at least one inlet 104A, 104B at the interface of each bearing 103A, 103B attached to each end of the housing 100. These inlets 104A, 104B are configured to receive cooling medium and may be natural inlets created by the interface when the rotor 102 is attached to the stator 101 using bearings or by other edge differences between the stator and rotor. Depending on the application of the electric motor, the cooling medium may be introduced via at least one inlet 104A, 104B in different ways.

[0081] In some embodiments, the electric motor is used in an environment other than aquatic, and thus the cooling medium is introduced from the outer container via an inlet (such as an interface associated with a bearing or any other suitable support element) and reintroduced into the container via any outlet as explained below.

[0082] Back Figure 1 A cooling medium, such as water, flows in through inlets 104A and 104B and through channel 106. Channel 106 is arranged between the molded rotor and the molded stator to guide the cooling medium in the axial direction of the housing 100 and is in fluid communication with at least one inlet 104A and 104B and at least one outlet 105A and 105B, thereby forming an internal cooling system for the electric motor. This internal cooling system is configured to cool the internal parts of the motor. The introduced cooling medium is then discharged from channel 106 via at least one outlet 105A and 105B, which is located on the rotatable outer portion 120 of the housing and configured to discharge the cooling medium by the centrifugal force (or rotational force) generated during the rotation of the rotor 102.

[0083] Outlets 105A and 105B are openings that pass through both the rotatable outer portion 120 of the housing and the rotor 102 and are in fluid communication with the internal passage 106. The shapes of outlets 105A and 105B are any of the following: circular opening, slit, square opening, star-shaped opening, borehole, and conical opening; or any type of small-diameter opening arranged in annular form or around the periphery of the rotatable outer portion 120 of the housing. Outlets 105A and 105B may be one or more and may be located anywhere within the rotatable outer portion 120 of the housing.

[0084] However, the magnets located inside the rotor limit the space available for setting these outlets. Therefore, the location of these outlets, the spacing between them, and the diameter of each outlet can all be varied.

[0085] Figure 1b A schematic diagram of a sub-device of an electric motor is shown, illustrating a stator 101 and a rotor 102. The stator and rotor are part of the electric motor and are arranged in a rotationally symmetrical manner. An additional channel 108 is shown at the center of the diagram. This additional channel extends axially through the center of the electric motor and is arranged to allow cooling medium to flow through the interior of the stator 101. The additional channel 108 extends along the motor axis of the electric motor. Thus, this inverted electric motor configuration includes a central channel 108 (referred to herein as the additional channel) extending along the motor axis of the electric motor through the center of the inner stator 101 for the cooling medium. The diagram also shows a channel 106 arranged between the rotor and stator to guide the cooling medium at least partially along the axial direction of the motor and in fluid communication with at least one inlet 104 and at least one outlet 105, thereby forming an internal cooling system for the electric motor. At least one inlet 104 is shown arranged on the inner surface of the stator 101. This inner surface faces the additional channel 108. At least one outlet 105 is arranged on the outer surface of the rotor 102. The figure shows four inlets and two outlets; however, it should be recognized that the examples shown are merely illustrative and other combinations are possible. The stator and / or rotor may be provided with inlets and / or outlets located on the stator and / or rotor and / or at the edges between the stator and rotor. The figure shows inlet 104 located on stator 101.

[0086] Figure 1cA schematic diagram of an inlet 104 with an extension 109c located at the edge of the inlet to guide the flow of cooling medium toward the inlet 104 is shown. The extension is located downstream of the inlet 104 in the flow direction of the cooling medium. The extension can have different shapes; the triangular shape shown is merely an example. In the example shown, the extension protrudes from the inner surface of the stator into an additional channel 108 to increase the flow of cooling medium from the additional channel through the inlet 104 to the channel 106 within the internal cooling system.

[0087] Figure 1d A schematic diagram of an inlet 104 with a recess 109d located at the edge of the inlet is shown to guide the flow of cooling medium toward the inlet 104. In the flow direction of the cooling medium, the recess 109d is located upstream of the inlet 104. The recess can have different shapes; a triangular cut-out shape is shown as an example. In the example shown, the recess is formed in the inner surface of the stator to increase the flow of cooling medium from the additional channel via the inlet 104 to the channel 106 of the internal cooling system.

[0088] In another exemplary embodiment, the electric motor is capable of operating in a submerged or immersed state and can be used in a variety of applications, such as excavation pumps, deep well pumps, sewage pumps, boats, ships, or submarines.

[0089] The electric motor can also be arranged to operate in a submerged state, and the cooling medium can be water. For a submersible electric motor, the cooling system described above can be enhanced by providing an additional channel 108 that extends axially through the center of the fixed internal portion of the housing and is arranged to allow the cooling medium to flow through. The center of the fixed internal portion 110 is hollow to allow water to flow axially through the outer portion of the stator 101. Water can be introduced through the hollow portion of the housing via a fan or propeller P located at the outer front of the rotor 102. Then, as... Figure 1 and Figure 3A , Figure 3B As shown, water is guided along the axial direction of the housing toward the back of the electric motor. The hollow portion or additional channel 108 can be configured as a single channel or multiple small channels or openings parallel to each other, allowing water to flow through. The more water flows through the additional channels, the faster the electric motor cools down.

[0090] In another exemplary embodiment, the electric motor is not located in an aqueous environment. Therefore, the additional channel 108 is closed or sealed at both ends, leaving an empty space inside the motor. This empty space may have at least one inlet and at least one outlet, wherein the inlet is for introducing cooling medium from an external container, and the outlet is for discharging the cooling medium to the same external container or another external container. The cooling medium cools the internal parts of the motor (specifically, the rotatable external part of the stator) when introduced into the additional channel 108. Other variations in the introduction or discharge of the cooling medium are also possible.

[0091] The motor may also include an additional channel 108. This additional channel 108 may be arranged to allow cooling medium to flow through the motor. The additional channel 108 may, for example, extend axially through the center of the motor. The additional channel may, for example, extend axially through the center of a fixed internal portion of the housing. By providing the additional channel, cooling medium can flow through the motor.

[0092] The electric motor may include at least one outlet, which may be located on an external portion of the housing and is adapted to discharge cooling medium from the channel by centrifugal force during the rotation of the rotor.

[0093] In another exemplary embodiment, the electric motor may include a housing, a stator, a rotor, a channel, and at least one outlet. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. The channel may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor. At least one outlet may be provided on the external portion of the housing and adapted to discharge cooling medium from the channel by centrifugal force during rotation of the rotor.

[0094] At least one inlet may be located on the inner surface of the fixed internal portion.

[0095] At least one entrance can be arranged on the stator facing the additional channel.

[0096] At least one inlet may be provided with a fluid guiding device, such as an extension located at the edge of the inlet, to guide the flowing cooling medium to the inlet. The extension may be located on a rearward portion of the inlet in relation to the flow of the cooling medium. The extension may also have a concave surface to further guide the flow of the cooling medium toward the inlet. According to some embodiments, at least one inlet may be provided with a fluid guiding device, such as a recess located at the edge of the inlet, to guide the flowing cooling medium to the inlet. The recess may be located on a forward portion of the inlet in relation to the flow of the cooling medium. The extension may also have a concave surface.

[0097] The location of the fluid guiding device can be determined based on the flow direction of the cooling medium during motor operation.

[0098] Additional channel 108 may be a central channel and / or a motor channel, or may be referred to as a central channel and / or a motor channel.

[0099] In another exemplary embodiment, the electric motor may include a housing, a stator, a rotor, and a channel. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. The channel may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor.

[0100] Figure 2A An exploded view of the rotatable outer portion 220 of the housing of an example electric motor according to the present disclosure is shown, and Figure 2B A perspective view of the rotatable external portion of the housing of an example electric motor according to the present disclosure is shown.

[0101] The housing 220 is cylindrical in shape and has an enveloping surface, a top surface, and a bottom surface. A series of openings 205A and 205B are visible on the outer enveloping surface of the housing 220. Openings 205A and 205B are spaced apart from each other and arranged along each end of the enveloping surface, forming an annular shape around the outer portion of the housing to allow cooling medium or water to be discharged from the fixed internal portion of the housing during operation. Each annular shape formed by the outlets 205A or 205B is located at a different distance from the inlet. These distances allow sufficient space for the introduced cooling medium or water to flow through the fixed internal portion of the housing, thereby reducing the internal temperature of the external motor.

[0102] In some embodiments, only some outlets are arranged in annular shape around the outer portion of the housing, while other outlets are located on different portions of the outer surface of the housing. In some examples, the outlets may be located in the space between the permanent magnets of the rotor, i.e., in the middle portion of the outer surface, and the outlet need not be shaped in any particular way, but simply need to allow water or cooling medium to drain from the housing in a suitable manner. Other examples may include only one outlet located at any position on the outer envelope surface 220.

[0103] Figure 2C A perspective view of the fixed internal portion 210 of the housing of an electric motor according to an example of the present disclosure is shown.

[0104] The fixed internal portion 210 of the housing supports the fixed portion of the motor (i.e., the stator). The fixed internal portion 210 includes a hollow structure on which the stator is mounted after being encapsulated in an epoxy layer. This epoxy layer is moldable and protects any molded device from any liquids, dust, sand, or moisture.

[0105] The molded stator is at least waterproof and dustproof. The same steps are used for the rotor, which is then mounted on the stator via bearings. These bearings allow the rotor to rotate freely without friction, thus creating a channel (such as a gap, cavity, or clearance) between the stator and rotor. Any liquid introduced into at least one inlet will pass through the channel to at least one outlet, and in this process, no leakage of the introduced liquid into the rotor or stator occurs.

[0106] The hollow section is large enough to allow the cooling medium or water to flow through the center of the motor without negatively impacting its efficiency.

[0107] Figure 3A and Figure 3B An example of a marine motor including the electric motor disclosed herein is shown.

[0108] Figure 3A The marine motor shown is Figure 1 The illustration shows an example of an implementation of an electric motor and its attachment to an external thruster. In the front view, the thruster can be seen positioned in front of the electric motor on a shaft connected to it. The electric motor generates rotational force or torque on the shaft, designed to rotate the thruster 330 to transmit power by converting rotational motion into thrust.

[0109] In other embodiments (not shown), the thruster may be attached to a rotatable external portion of the housing to utilize the external rotation of an electric motor. Other configurations are also possible.

[0110] The blades of the thruster 330 are specifically designed to generate a pressure difference that accelerates the water passing through the thruster 330 when the motor is submerged in water.

[0111] The cooling water not only flows along the outer surface of the electric motor, but also through an additional channel 308 located inside the structure, in order to reduce the heat in the internal parts of the motor. Figure 3B Another view of the electric motor is shown, which shows the end of an additional channel 308 in the form of a pipe or passage.

[0112] The epoxy layer can be at least partially electrically insulating. For example, the electrical insulation properties of an at least partially electrically insulating epoxy layer can be greater than 100 ohms per mm of thickness. The electrical insulation properties of an electrically insulating epoxy layer can also be greater than 1 kiloohm per mm of thickness, 10 kiloohms per mm of thickness, 100 kiloohms per mm of thickness, 1 megaohm per mm of thickness, 10 megaohms per mm of thickness, 100 megaohms per mm of thickness, 1000 megaohms per mm of thickness, or 10000 megaohms per mm of thickness.

[0113] The epoxy layer can be electrically insulating. For example, the electrical insulation properties of an electrically insulating epoxy layer can be greater than 100 ohms per mm of thickness. The electrical insulation properties of an electrically insulating epoxy layer can also be greater than 1 kiloohm per mm of thickness, 10 kiloohms per mm of thickness, 100 kiloohms per mm of thickness, 1 megaohm per mm of thickness, 10 megaohms per mm of thickness, 100 megaohms per mm of thickness, 1000 megaohms per mm of thickness, or 10000 megaohms per mm of thickness.

[0114] The epoxy layer can be at least partially thermally conductive. For example, the thermal conductivity of a partially thermally conductive epoxy layer can be greater than 0.5 watts per millikelvin (W / mK). The thermal conductivity of a thermally conductive epoxy layer can also be 1 W / mK.

[0115] The epoxy layer can be thermally conductive. For example, the thermal conductivity of a thermally conductive epoxy layer can be greater than 0.5 watts per millikelvin (W / mK). The thermal conductivity of a thermally conductive epoxy layer can also be 1 W / mK.

[0116] The epoxy layer may be at least partially thermally conductive and at least partially electrically insulating. For example, the electrical insulation property of an at least partially electrically insulating epoxy layer may be greater than 100 ohms per mm of thickness. The electrical insulation property of an electrically insulating epoxy layer may also be greater than 1 kiloohm per mm of thickness, 10 kiloohms per mm of thickness, 100 kiloohms per mm of thickness, 1 megaohm per mm of thickness, 10 megaohms per mm of thickness, 100 megaohms per mm of thickness, 1000 megaohms per mm of thickness, or 10000 megaohms per mm of thickness. For example, the thermal conductivity of an at least partially thermally conductive epoxy layer may be greater than 0.5 watts per millikelvin (W / mK). The thermal conductivity of a thermally conductive epoxy layer may also be 1 W / mK.

[0117] The epoxy layer can be thermally conductive and electrically insulating. For example, the electrical insulation property of an electrically insulating epoxy layer can be greater than 100 ohms per mm of thickness. The electrical insulation property of an electrically insulating epoxy layer can also be greater than 1 kiloohm per mm of thickness, 10 kiloohms per mm of thickness, 100 kiloohms per mm of thickness, 1 megaohm per mm of thickness, 10 megaohms per mm of thickness, 100 megaohms per mm of thickness, 1000 megaohms per mm of thickness, or 10000 megaohms per mm of thickness. For example, the thermal conductivity of a thermally conductive epoxy layer can be greater than 0.5 watts per millikelvin (W / mK). The thermal conductivity of a thermally conductive epoxy layer can also be 1 W / mK. According to some embodiments, the epoxy layer can have a low viscosity, for example, a viscosity in the range of 1400 to 2200 cPs at 23 degrees Celsius and 100 rpm. The epoxy layer can also be homogeneous and / or thermally stable.

[0118] The epoxy layer can be cured at room temperature.

[0119] According to some embodiments, an electric motor may include a housing, a stator, a rotor, and channels. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. Channels may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor. The epoxy layer may be thermally conductive and electrically insulating.

[0120] Multiple magnets of the rotor can be arranged in a magnetization pattern that concentrates the combined magnetic flux of these magnets to the center of the rotor. The rotor can be hollow, for example, having a cylindrical shape, so that the magnetic flux can be concentrated in the hollow central portion of the cylindrical rotor. This hollow central portion may include other components.

[0121] The rotor's multiple magnets can be arranged in a Heilbeck configuration, thereby directing the magnetic field strength towards the center of the rotor. The rotor can also be hollow, for example, having a cylindrical shape, so that the magnetic flux can be concentrated in the hollow central portion of the cylindrical rotor. This hollow center may include other components.

[0122] Magnets can include high-throughput alloys, such as neodymium steel.

[0123] Magnets arranged in a Heilbeck configuration can be arranged in a spatially rotating magnetization pattern to enhance the magnetic field on one side of the configuration while canceling the magnetic field on the other side of the configuration, bringing it close to zero.

[0124] According to some embodiments, an electric motor may include a housing, a stator, a rotor, and a channel. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotor may include magnets arranged in a Helbeck configuration. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. The channel may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor.

[0125] The motor may also include at least one propeller. The at least one propeller may be arranged on and / or connected to a rotatable part of the motor (such as a rotor).

[0126] The motor may also include a thruster connector, wherein the thruster connector is arranged to connect to at least one thruster.

[0127] The propulsion unit may include a hub and multiple radial blades arranged in a pitch to form a helical pattern, thereby converting rotational power into linear thrust by acting on a working fluid (such as water) during rotation.

[0128] The propulsion device can be a propeller.

[0129] The thruster can be configured to operate while submerged in water.

[0130] Motors may also include impellers.

[0131] According to some embodiments, an electric motor may include a housing, a stator, a rotor, channels, and a propeller. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. Channels may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor. A propeller may be arranged on the rotor, and the epoxy layer may be thermally conductive and electrically insulating.

[0132] According to some embodiments, an electric motor may include a housing, a stator, a rotor, a channel, and a propeller. The housing may have a fixed internal portion and a rotatable external portion. The stator may be supported by the fixed internal portion of the housing. The rotor may be attached to the rotatable external portion of the housing, and the rotor may be configured to rotate freely about the stator. The rotatable external portion may have at least one inlet configured to receive cooling medium and at least one outlet configured to discharge cooling medium. The stator and rotor may each be molded in a respective epoxy layer. A channel may be arranged between the molded rotor and the molded stator to guide cooling medium in the axial direction of the housing and to be in fluid communication with at least one inlet and at least one outlet, thereby forming an internal cooling system for the electric motor. A propeller may be arranged on the rotor.

[0133] The motor may include a second housing and be configured for jet propulsion. The second housing may be arranged to at least partially enclose the motor and the propulsion unit.

[0134] The motor may have a rotor located inside a hollow stator and a propeller located inside the hollow rotor.

[0135] The motor may have a rotor located inside a hollow stator and a propeller located inside the hollow rotor.

[0136] The motor may include a second housing and be configured for jet propulsion. The second housing may be arranged to at least partially enclose the motor and the propulsion unit.

[0137] Electric motors are suitable for powering underwater vehicles, such as boats, motorboats, ships, and submarines. The motors power propulsion and operate while submerged.

[0138] The electric motor can be configured as an external engine, an internal engine, or a pod.

[0139] The electric motor may also include mounting devices adapted to mount the motor to the vessel. For example, the motor may be mounted on a beam, stern, hull, rudder, and / or hydrofoil.

[0140] Electric motors can be configured to be mounted on, for example, beams, sterns, hulls, rudders, and / or hydrofoils.

[0141] The electric motor according to this disclosure can be used not only in marine or naval applications, but also in other applications (e.g., drones, electric vehicles, and a wide variety of electric toys). However, in non-military applications, a cooling medium is needed instead of water. This cooling medium can be introduced into a closed or sealed channel 308 through at least one inlet and discharged through at least one outlet (not shown). Both the at least one outlet and the at least one inlet can be connected to an external container or similar device that holds the cooling medium. In some applications, a fan or similar device is needed instead of a propeller for proper operation.

[0142] Those skilled in the art will recognize that the present invention is not limited to the preferred embodiments described above. They will also recognize that modifications and variations can be made within the scope of the appended claims. Furthermore, by studying the accompanying drawings, the disclosure, and the appended claims, those skilled in the art can understand the disclosed embodiments and can make variations to the disclosed embodiments in practicing the claimed invention.

Claims

1. An electric motor, comprising: - Housing (100) having a fixed internal portion (110) and a rotatable external portion (120); - The stator (101) is supported by the fixed internal portion (110) of the housing (100); - A rotor (102), attached to the rotatable outer portion (120) of the housing (100), the rotor being configured to rotate freely about the stator (101); Its features are: - The rotatable outer portion (100) has at least one inlet (104A, 104B) configured to receive a cooling medium and at least one outlet (105A, 105B) configured to discharge the cooling medium. - The stator (101) and the rotor (102) are each molded in a corresponding epoxy layer (107A, 107B). A channel (106) is provided between the molded rotor and the molded stator, the channel guiding the cooling medium in the axial direction of the housing (100) and in fluid communication with at least one inlet (104A, 104B) and at least one outlet (105A, 105B), thereby forming an internal cooling system for the electric motor. - The internal cooling system also includes an additional channel (108) that extends axially through the center of the fixed internal portion of the housing and is arranged to allow the cooling medium to flow through.

2. The electric motor according to claim 1, wherein, The at least one outlet (105A, 105B) discharges the cooling medium by the centrifugal force generated during the rotation of the rotor (102).

3. The electric motor according to claim 1 or 2, wherein, Some of the multiple outlets (105A, 105B) are arranged around the periphery of the rotatable outer portion of the housing.

4. The electric motor according to claim 1 or 2, wherein, The rotatable outer portion of the housing is at least partially cylindrical.

5. The electric motor according to claim 1 or 2, wherein, The at least one outlet (105A, 105B) is any one of a circular opening, a slit, a star-shaped opening, a square opening, a borehole, and a conical opening.

6. The electric motor according to claim 1 or 2, wherein, The electric motor is configured to operate in a submerged state, and the cooling medium is water.

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