Drive wheel with electric wheel hub motor

Abstract

Drive wheel with electric wheel hub motor comprising at least one wheel (5), at least one electric motor (10) by means of which the at least one wheel (5) can be driven, and at least one electrically rechargeable energy storage system for supplying at least one electrical component of the electric vehicle (1), characterized in that a) the tire structure of at least one wheel (5) of the electric vehicle (1) includes an electric motor (10) designed to exert a torque on the corresponding wheel (5) through the interaction of rotor (11), stator (12), motor shaft (13), rim (8) and electromagnetic fields, wherein e) the at least one electric motor (10) is a wheel hub motor with a housing (9), stator (12), coil core (15), windings (16), rotor (11) connected to the rim (8) of the wheel (5) in a rotationally fixed manner, and electromagnetic fields to exert a torque on the corresponding wheel (5), wherein b) the stator (12) of the wheel hub motor (10) is equipped with the permanent magnets (17) made of magnetic plastics in the form of the coil cores (15), wherein c) the windings (16) are made of electrically and thermally conductive carbon nanomaterials.

Description

Technical area

[0001] The present invention relates to a drive wheel with an electric wheel hub motor according to the preamble of claim 1. State of the art

[0002] Current state-of-the-art electric vehicle and drive concepts, which use various types of electric motors, can only offer limited range.

[0003] Conventional electric vehicles have heavy, multi-part battery packs and a shatter-resistant structure. Batteries must be protected from damage, temperature differences, and spontaneous combustion in accidents. These batteries account for a disproportionate share of the vehicle's total weight. This requires powerful electric motors or an increase in their number in a car, which leads to increased consumption of construction materials. This reduces the ultimate efficiency of the electric motor.

[0004] The production of drive motors consumes a great deal of energy and is still relatively expensive. Electric motors use both iron and copper. Copper production consumes enormous amounts of water, chemicals, and electricity. The extraction and production of non-ferrous metals used in electric motors is not the most environmentally friendly process...Therefore, electric cars are by no means climate-neutral.

[0005] There are various types of electric motors installed in cars. One type of drive is the wheel hub motor. The wheel hub drive combines the motor, power electronics, digital control, and friction brakes in a compact housing. The hub motor is integrated into the hub of the front or rear wheel, or both, usually decentralized within the rim, and thus transfers its power to the wheel hub without loss. The wheels are thus driven directly by the motor, thus achieving high efficiency.

[0006] The major advantage of positioning the motor in the wheel hub is significantly reduced drive component consumption. Gearboxes, differentials, and drive shafts are eliminated thanks to the direct drive. This minimizes power loss from electric motors and weight, as well as simplifying the vehicle structure. By using an electric hub motor, electric vehicles can be redesigned into a completely new vehicle architecture with high space efficiency. The space originally reserved for a central motor unit can now be used for other purposes.

[0007] Depending on the number of wheels, electric vehicles can be equipped with wheel hub motors. This allows an electric vehicle to continue driving even if one of the electric motors fails.

[0008] The compactness and simplicity of the wheel hub motor are practical for building modular platforms and integrating advanced control systems - be it automatic traction distribution between the wheels or rear axle steering.

[0009] In a four-motor arrangement, the independent control of the motors allows turning on the spot by turning the right and left wheels in opposite directions

[0010] The main disadvantages of wheel hub motors include the high unsprung mass of the drive unit under the spring and damper, resulting from the weight of the wheel hub modules, and especially the stator windings and cooling system. This not only results in reinforced mechanical components for the axle suspension, but also has a significant impact on suspension comfort, especially at higher speeds. For this reason, wheel hub concepts have often failed due to the lack of integration options for conventional suspension or braking components.

[0011] Care must be taken to prevent the wheel hub motor from overheating (the motor housing should not exceed 70 degrees Celsius). Therefore, cooling of the drive components is essential, especially under heavy loads. In addition to the cables, cooling hoses and conventional hydraulic lines must be routed to the wheel.

[0012] In addition, wheel hub motors are more exposed to environmental influences (e.g., moisture, dirt, splashing or jet water, dust, saline media) and require sealing and rust protection to protect against dust, water, or mechanical influences.

[0013] By reducing the unsprung mass, the main deficiencies of the wheel hub motor can be comprehensively eliminated. Various design solutions are known for reducing the weight of the wheel hub motor, for example, the use of motors with ironless field coils or reluctance motors.

[0014] The disclosure EP000001895640B1 provides a wheel hub motor with a stator connected in a rotationally fixed manner to a wheel hub and a rotor connected in a rotationally fixed manner to a wheel rim, comprising ironless field coils connected to a control unit and permanent magnet rings with an annular air gap, wherein sections of the field coils immersed in the air gap are aligned parallel to the rotational axis of the wheel hub motor. The field coils are formed from flat strip material, comprising a foil body with an electrically insulating carrier foil and an electrically conductive layer arranged on the carrier foil, and the field coils are designed as frame coils.

[0015] An ironless winding is already known from US-PS 4,130,769, in which the individual partial coils are wound and baked in one plane and only then have to be bent into the curved shape.

[0016] When using ironless field coils, the bending process can cause the welds of the enameled wire or insulating carrier foil to break, resulting in a loss of stability. Another disadvantage is that the bending process causes the windings to no longer assume an ideal position. The term "ironless" is intended to exclude any magnetic materials in the field coil, which negatively impacts the properties of the electric motor.

[0017] DE102011081507B4 discloses a reluctance motor comprising a stator with a plurality of successively excitable phase windings and a rotor magnetized to seek a position of minimum reluctance within a progressively moving electromagnetic field generated by the phase windings, with first controlled switching means in series relative to a DC power supply with at least one pair of each phase winding and with means for controlling the first switching means to generate the progressively moving electromagnetic field,

[0018] The main disadvantage of reluctance motors is their pulsating torque, which is particularly noticeable with a small number of stator poles. Further disadvantages include a low power-to-weight ratio and pulsating radial forces between the rotor and stator, which place stress on the bearings and are responsible for comparatively high noise levels.

[0019] To reduce the heating of the wheel hub electric motor, various design solutions are known, for example the use of mechanical, hydraulic or ventilation devices.

[0020] DE102011081507B4 discloses a shielding device for thermally shielding the rotor and / or stator of an electric motor against the introduction of heat for an electric motor drive unit for an electric and / or hybrid vehicle, comprising an electric motor with a rotor and a stator and a friction brake, wherein the shielding device comprises: an annular base body and at least one coolant line for cooling the shielding device with a coolant, wherein the coolant line is integrated into the annular base body.

[0021] DE102011081660B4 discloses a drive system for a vehicle, having at least one drive system interior, comprising an electric motor with a stator and a rotor and a ventilation device for ventilating and venting the drive system interior of the drive system, wherein the ventilation device comprises at least one air supply device for supplying air into the drive system interior and at least one air discharge device for discharging air from the drive system interior, wherein the air discharge device comprises a valve, wherein the valve of the air discharge device is designed to allow air to flow out of the drive system interior and to prevent air from flowing into the drive system interior.

[0022] The disadvantages of the technical solutions in DE102011081507B4, DE102011081660B4, and others represent an attempt to eliminate one of the main disadvantages of electric wheel motors—their heating during movement—by increasing the mass of electric wheel motors through the introduction of new structural elements. In general, cooling electric wheel motors with water at low temperatures is problematic.

[0023] Now, the use of electrically and thermally conductive carbon nanomaterials with low resistance and low heat generation, plastic magnets, carbon fibers, and composite materials can significantly reduce the weight of unsprung masses and the concomitant heating of engine components. Heating of engine components can also be reduced by switching engine operation modes. Description of the invention

[0024] The present invention is based on the object of creating an innovative, efficient and economical drive wheel with an electric wheel hub motor, which simultaneously overcomes the design deficiencies of known wheel hub motors by changing the concept of the electric drive of cars.

[0025] According to the invention, the above object is achieved according to the preamble of claim 1 in conjunction with the characterizing features. Advantageous embodiments and further developments of the electric wheel hub motor according to the invention are specified in the dependent subclaims. Brief description of the drawings

[0026] Further objects, features, advantages and possible applications of the electric wheel hub motor according to the invention will become apparent from the following description of an embodiment with reference to the drawings.

[0027] The drawings show Fig. 1 a schematic view of the electric vehicle; Fig. 2 shows an electric wheel hub motor according to an embodiment of the invention in a simplified detailed representation; Implementation of the invention

[0028] The electric vehicle (1) according to the invention ( Fig. 1) consists of a chassis (3), at least one wheel (5), at least one body (6), at least one electric wheel hub motor (10) by means of which the at least one wheel (5) can be driven, and at least one energy storage system which can be recharged with electrical charge for supplying at least one electrical component of the electric vehicle (1).

[0029] On both sides of the electric vehicle (1) ( Fig. 1) preferably comprises at least two independently suspended wheel sets comprising rigid conventional wheels (5) and a tire (7) mounted thereon, which are attached to suspension arms (2). These are advantageously rigidly connected to the chassis (3). A steering element (4) is attached to the chassis (3), as well as at least one graphene supercapacitor battery (19) known in the art for each wheel (5), and electrical equipment (not shown here).

[0030] Electric wheel hub motor (10) ( Fig. 2) is preferably a two-mode electric vehicle drive. It consists of a housing (9), a rotor (11), a stator (12), a motor shaft (13), and Hall sensors (not shown here) in the form of a brushless wheel hub motor known in the art. On the externally rotating rotor (11) there are permanent magnets (14) made of neodymium, whose alternating north and south poles are directed towards the center of the circle and influence each other: like magnetic poles repel each other, and unlike magnetic poles attract each other. Magnets made of the rare earth material neodymium have several times the magnetic force of ferrite-bonded magnets, but for political, economic, and technical reasons they are replaced by plastic magnets. The stator (12) contains a coil core (15) onto which windings (16) made of insulated, conductive copper wire are wound.The polarity of the electromagnet, i.e. the orientation of the north and south poles, depends on the current direction in the windings (16).

[0031] The iron cores, permanent magnets, and copper windings form the main weight of the wheel hub motor. In view of the purpose of the present invention, the iron cores are preferably replaced by non-metallic plastics with permanent magnetic properties, and the copper windings are replaced by insulated, electrically and thermally conductive carbon nanomaterials with low resistance and low heat generation. This eliminates the fundamental design flaw of the wheel hub motor. The coil cores (15), which serve as permanent magnets, are aligned so that the opposite poles of the rotor and stator magnets are always facing each other ( Fig.2). Alternatively, electrically switchable permanent magnets can be used. They gain or lose their adhesive power under the influence of a short electrical voltage pulse, allowing energy to be saved and magnetic properties to be controlled by switching them on or off. The disadvantages of conventional motors are the complicated geometry of the field coils and the large radial extension, which, for example, prevents the motor from being housed in a wheel hub. As an example for the production of structural elements, the possibility of using magnetic and conductive neodymium-bonded plastics is considered. Due to its higher magnetic force, this magnetic plastic is suitable for injection molding, and thanks to its high dimensional accuracy, it is suitable for high-precision parts. Due to its properties, neither expensive magnetic field molding machines nor tools are required. The parts can be manufactured relatively inexpensively.

[0032] Depending on the parameters of the wheel hub motor, the parameters of the permanent magnets on the rotor (14) and permanent magnets on the stator (17) (shape, size, angle of inclination to each other, power, as well as the size of the air gap between the rotor (11) and the stator (12)) should be clarified.

[0033] The rotor (11) and stator (17) of the electric wheel hub motor (10), power electronics, and brake (not shown here) are housed within the rim (8). This allows for separate speed and direction control, with each wheel (5) receiving as much torque as required for the respective driving situation. Furthermore, the drive shafts are eliminated. The motor shaft (13) is attached to suspension arms (2).

[0034] The electric wheel hub motor (10) is preferably used only to start the electric vehicle (1) and to change the driving mode (first mode). In stable driving mode, the electric wheel hub motor (10) is switched off, and the wheels (5) continue to rotate due to the mutual influence of the permanent magnets on the rotor (14) and the permanent magnets on the stator (17), as well as due to the rotation of the wheel masses, which act as a flywheel (second mode).

[0035] When the electric vehicle (1) is produced at the manufacturer's plant, pre-charged graphene supercapacitor batteries (19) are installed on it to power the electrical equipment of the electric vehicle (1), including the electric wheel hub motor (10).

[0036] When the electric wheel hub motor (10) is powered by one or more graphene supercapacitor batteries (19) (first modes), the rotor (11) rotates relative to the stator (12) due to the attractive and repulsive forces of the electromagnets of the stator (12) and the permanent magnets (14) of the rotor (11). To ensure that the rotor (11) continues to rotate, the controller (25) reverses the poles of the electromagnets of the stator (12) accordingly.

[0037] The electromagnets of the stator (12) are covered, for example, with Hall sensor shielding plates (not shown here) to block the magnetic flux from the permanent magnets (14) on the rotor (11) when the opposite poles of the stator and rotor magnets are attracted to each other and the end of the rotor magnet (14) is not aligned with the same pole of the stator magnet. The rotation of the rotor (11) ultimately sets the associated wheel (5) in rotation.

[0038] When the electric wheel hub motor (10) is switched off (second mode), the permanent magnets (14) and (17) built into the rotor (11) and stator (12) are attracted to each other by opposite poles, causing the rotor (11) to rotate around the axis by a certain angle until one of the extreme positions is reached, the end of the rotor magnet (14) is not aligned with the same pole of the permanent magnet on the stator (17). The influence of the magnetic flux is eliminated in this case by rotation of the wheel masses flywheel. With further rotation of the rotor (11), the opposite poles of the rotor (11) and permanent magnets on the stator (17) interact again and the rotor (11) continues to rotate by a certain angle, the cycle repeats. The permanent magnets on the stator (17) and the permanent magnets on the rotor (14) are arranged at each angle of rotation in such a way that at any time and at any angle of rotation one of the rotor magnets always provides the attraction.As a result, the rotor (11) rotates together with the wheels (5) around the motor shaft (13).

[0039] Electrical energy for starting electric motors is transmitted from one or more graphene supercapacitor batteries (19), which are connected to switching, protection, and control means not shown here in a manner known in the art, for example, resonant magnetic coupling and the range of technical means provided for in the A4WP standard. In the same way, current is transmitted to charge the graphene supercapacitor battery (19), which is generated when the vehicle descends a hill, coasts to a stop, or brakes the motor with a wheel (5), or due to the interaction of the magnetic fields of permanent magnets (17) of the stator (12) and the windings (16). This allows energy to be transmitted over reasonable distances via a single transmitter to multiple devices. This also offers enormous advantages in cabling, as the length and cross-section of the cable can be significantly smaller than in known analogues of classic central drives.Electronic components and circuit boards must be developed. The vehicle speed and electric vehicle drive modes are adjusted by the onboard computer. This ensures continuous operation of the electric vehicle (1). Special embodiments of the invention

[0040] The drive wheel with electric wheel hub motor according to the invention is characterized in that:

[0041] a) the tire structure of at least one wheel (5) of the vehicle (1) contains an electric motor (10) which is designed to exert a torque on the corresponding wheel (5) through the interaction of the rotor (11), stator (12), motor shaft (13), rim (8) and electromagnetic fields, wherein

[0042] b) the at least one electric motor (10) is a wheel hub motor with a stator (12) with windings (16), a rotor (11) connected in a rotationally fixed manner to the rim (8) of the wheel (5), and electromagnetic fields in order to exert a torque on the corresponding wheel (5), wherein a plurality of the coil cores (15) of the stator (12) of the wheel hub motor (10) are made of non-metallic plastics with permanently magnetic properties and the windings (16) are made of electrically and thermally conductive carbon nanomaterials, and permanent magnets (14) are arranged on the rotor (11) in order to cause rotation of the wheel (5) through the interaction of the electromagnetic fields of the stator (12) and the magnetic fields of the permanent magnets (14) of the rotor (11).

[0043] c) In order to reduce design defects of the wheel hub motor (10), in particular the weight, heating and rust of drive components, the iron cores (15) of the stator (12) are replaced by non-metallic plastics with permanent magnetic properties and the copper windings (16) of the stator (12) are replaced by insulated electrically and thermally conductive carbon nanomaterials with low resistance and low heat generation and the power supply of the wheel hub motor (10) is switched off in the stable movement mode in order to dispense with the cooling system of the electric motor (10) and reduce its weight.

[0044] d) The electrical component of the electric vehicle (1) may further be connected to the outputs and inputs of the graphene supercapacitor batteries (19) via a resonant magnetic coupling to ensure energy transmission over reasonable distances from graphene supercapacitor batteries (19) and multiple devices through a single transmitter and to significantly reduce the length and cross-section of the cable.

[0045] e) The electrical energy for drive and vehicle systems of the electric vehicle (1) can therefore preferably be provided by graphene supercapacitor batteries (19), some of which alternately supply the electrical components of the electric vehicle (1) with power while driving, while others are charged by a tire (7) with a device for generating electrical power (18) (is the subject of a separate application).

[0046] f) It is particularly advantageous that the sealing and rust protection of the electric wheel hub motor (10) is carried out by applying water-repellent carbon nanomaterials.

[0047] g) The solution according to the invention provides that the starting and acceleration of the electric vehicle (1) preferably takes place in a first mode by at least one pre-charged graphene super-capacitor battery (19) under the influence of attractive and repulsive forces from the electromagnets (17) of the stator (12) and the permanent magnets (14) of the rotor (11), and in a stable second driving mode the electric wheel hub motor (10) is switched off and the wheels (5) rotate due to the mutual influence of the permanent magnets (14) on the rotor (11) and the permanent magnets (17) on the stator (12), wherein the movement through the extreme point in the same direction, when the pole of the rotor magnet (14) is aligned with the same pole of the stator magnet (17), takes place due to the rotation of the masses of the wheel (5), which functions as a flywheel.

[0048] The implementation of the invention makes it possible to create a climate-neutral electric vehicle (1) and to increase the range and driving time. List of reference numbers 1 electric vehicle 2 suspension arms 3 Carriage frame 4 steering elements 5 wheel 6 Body 7 tires 8 rim 9 housings 10 electric wheel hub motor 11 Rotor 12 Stator 13 Motor shaft 14 permanent magnets on the rotor 15 coil core 16 windings 17 permanent magnets on the stator 18 Device for generating electric current 19 Graphene Supercapacitor Batteries QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 000001895640B1

[0014] US Patent 4,130,769

[0015] DE 102011081507B4 [0017, 0020, 0022] DE 102011081660B4 [0021, 0022]

Claims

[1] Drive wheel with electric wheel hub motor, which comprises at least one wheel (5), at least one electric motor (10) by means of which the at least one wheel (5) can be driven, and at least one energy storage system rechargeable with electrical charge for supplying at least one electrical component of the electric vehicle (1), characterized by , that a) the tire structure of at least one wheel (5) of the electric vehicle (1) contains an electric motor (10) which is designed to exert a torque on the corresponding wheel (5) through the interaction of the rotor (11), stator (12), motor shaft (13), rim (8) and electromagnetic fields, wherein e) the at least one electric motor (10) is a wheel hub motor with a housing (9), stator (12), coil core (15), windings (16), the rotor (11) connected in a rotationally fixed manner to the rim (8) of the wheel (5), and electromagnetic fields in order to exert a torque on the corresponding wheel (5), wherein b) the stator (12) of the wheel hub motor (10) is equipped with the permanent magnets (17) made of magnetic plastics in the form of the coil cores (15), wherein c) the windings (16) are made of electrically and thermally conductive carbon nanomaterials. [2] Drive wheel with electric wheel hub motor according to claim 1 characterized by that the weight of the electric wheel hub motor (10) and the effects of the unsprung mass are reduced and the rotation of the wheel (5) will continue when the motor is switched off in the stable movement mode through the interaction of the magnetic fields of the permanent magnets (17) of the stator (12) and the magnetic fields of the permanent magnets (14) of the rotor (11) by replacing the iron cores of the stator (12) of the electric motor (0) with a plurality of coil cores (15) made of non-metallic plastics with permanent magnetic properties. [3] Drive wheel with electric wheel hub motor according to claim 1 characterized bythat the weight of the electric wheel hub motor (10), effects of the unsprung mass and heating of the motor parts are reduced by replacing the copper wire of the windings (16) of the stator (12) with electrically and thermally conductive carbon nanomaterials with low resistance and low heat generation. [4] Drive wheel with electric wheel hub motor according to claim 1 characterized by that the electrical component of the electric vehicle (1) is connected to the outputs and inputs of the at least one graphene supercapacitor battery (19) via a resonant magnetic coupling in order to ensure energy transmission over reasonable distances from graphene supercapacitor batteries (19) and several devices through a single transmitter, significantly reducing the length and cross-section of the cable. [5] Drive wheel with electric wheel hub motor according to claim 1 characterized bythat the starting and acceleration of the electric vehicle (1) in a first mode via at least one pre-charged graphene supercapacitor battery (19) takes place under the influence of attractive and repulsive forces from the electromagnets of the stator (12) and the permanent magnets (14) of the rotor (11), and in a stable second driving mode, the electric wheel hub motor (10) is switched off and the wheels (5) rotate due to the mutual influence of the permanent magnets (14) on the rotor (11) and the permanent magnets (17) on the stator (12), wherein the movement through the extreme point in the same direction, when the pole of the rotor magnet (14) is aligned with the same pole of the stator magnet (17), takes place due to the rotation of the masses of the wheel (5), which functions as a flywheel [6] Drive wheel with electric wheel hub motor according to claim 1 characterized bythat the electrical energy for drive and vehicle systems of the electric vehicle (1) is provided by graphene supercapacitor batteries (19), some of which alternately supply the electrical components of the electric vehicle (1) with power while driving, while others are charged by at least one tire (7) with a device for generating electrical current (18). [7] Drive wheel with electric wheel hub motor according to claim 1 characterized by that the coil cores (15) are designed as permanent magnets (17) [8] Drive wheel with electric wheel hub motor according to claim 1 characterized by that the field coil heads of the coil cores (15) form a preferably pot-shaped body. [9] Drive wheel with electric wheel hub motor according to claim 1 characterized by that the sealing and rust protection of the housing (9) of the electric wheel hub motor (10) is achieved by applying water-repellent carbon nanomaterials.

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