Subject Matter of the Invention

The subject of the invention is a compact, in-wheel rim, torus type, brushless and axial electric motor having high torque and power values.

State of the Art

Today' s electric motors are generally used for propulsion of systems, and developed in different types and features. In industrial applications, due to their advantages such as providing high efficiency and power density, brushless direct current motors are being used quite considerably.

In brushless direct current motors, there are semiconductor circuit components performing the task of switching high current, and an electronic controller provided with a microcontroller providing the relative timing for switching.

In the state of art, the controller for the continuity of motor rotation and the torque control controls the motor in a precise way. The controller performs this operation by using the hall effect sensors. Speed control can be achieved by adjusting the torque values by the controller. Thanks to being brushless, these types of motors in which the friction effect is minimized have high efficiency. They can operate silently in high speed. They do not have the problems such as arching and producing carbon dust. Due to not having the risk of ignition, they are suitable for use in gaseous industrial zones having explosion hazard. Their power density is high. Furthermore, they allow the development of compact designs. There is almost no need for maintenance. In numerous different countries across the world, there are many brushless direct current motors with different powers and models, marketed by different manufacturers.

In the invention according to the patent document US2018/0026500A1 of the state of the art, the magnets placed on two sides of stator are fixed to the rotor. The coils on the stator are between these two permanent magnets. The outer body is fixed. Within the body, motor performs its rotor rotational motion. However, this is not favourable for an in wheel direct drive application. It is rather developed for hybrid systems in which a power train is needed.

Patent documents EP2451059B1 and US009862264B2 can be cited as other examples. Said documents relate to the in-wheel direct drive electric motors developed for cars and other vehicles. In these patents, the wheel can be directly driven by mounting the motor block into the wheel rim. A stator, a rotor plate, a rotor pipe, a seat system and a brake system are mounted into the wheel rim by means of a simple mechanical connection. The motor used in the wheel rim has a radial structure rather than an axial structure.

As another example, the patent document WO2018/015293A1 relates to the axial flux electric machines. More particularly, it relates to a stator for an axial flux electric machine and a method for producing the same. The invention comprises an axial flux motor cover, a plurality of long sections and a stator consisting of a plurality of separate radially extending and sticking out ferromagnetic materials, an electrically insulant filler. The outer body is fixed. Within the body, rotor performs rotational motion. However, this is not favourable for an in-wheel direct drive application. It is rather developed for hybrid systems in which a power train is needed. As mentioned in the above documents, electric motors in the art are generally divided into two groups: out-wheel axial type motors and in-wheel radial type motors. The aforementioned technical documents are insufficient in terms of developing powerful axial type electric motors mounted in a wheel, and unable to satisfy this need. The radial type motors used in wheels are known to be less powerful.

There are some electric motors developed as a solution for this problem, and are explained below.

Non-patent document "Optimal design and control of axial-flux brushless dc wheel motor for electrical vehicles", relates to an axial flux, brushless, DC motor for electrical vehicles and control thereof. In the aforementioned document, an axial flux fixed magnet motor is developed to achieve a high torque/weight ratio and motor efficiency. It is suitable for direct driven wheel applications.

The invention according to the patent document US2012169154A relates to an axial flux brushless electric motor that can be used in various applications including driving a drive wheel of a vehicle. In an embodiment of the invention, the electric motor comprises a rotor comprising a plurality of permanent magnets defining a plurality of rotor poles. Electric motor also comprises a stator axially spaced from the rotor and at least one coil for conducting current; an electronic controller for controlling the current supplied to the at least one coil to rotate the rotor, and a consolidating material in which the at least one coil and the electronic controller are embedded.

The electric motors described in the above documents do not have all the features together such as having two rotors, being torus type, being brushless and having an axial flux motor to be mounted within the dead zone in the wheel rim of the electrical vehicles.

In order to overcome the aforementioned disadvantages, it is aimed to develop a compact brushless double rotor torus type axial electric motor which can operate without a powertrain by mounting to the dead area in the wheel rim and has high torque and power values. The double rotor and torus type structure of the invention allows to achieve a higher power density in unit area compared to both motor types.

Detailed Description of the Invention

The invention relates to a double rotor torus type brushless axial direct current motor that has high power density and operates in the wheel rim without needing any power train in the applications focusing on efficiency, particularly in electrical vehicles.

An object of the invention is to satisfy the need for an electric motor that has high power density, and the features of lightness and compactness, can be mounted in the wheel rim and provides power increase by paralleling.

Another object of the invention is to allow the axial motor rotor to be used independently in the wheel rim instead of the fixed body.

The electric motor of invention comprises in general coils (19) (electromagnet) in a particular order and number that are triggered by placing them such that both poles thereof can be used in order to convert electrical energy to axial motion energy; strong, heat resisting fixed magnets in a particular order and number that are placed such that there is air gap for both poles (n-s) of the coil (19) by creating a magnetic field ; and double rotor, wherein the electric motor is a compact, torus type, brushless, axially operating, direct current motor that has high torque and power values and is placed within the wheel rim.

An embodiment of the invention is a compact, in-wheel rim, torus type, brushless, axial electric motor that has high torque and power values and converts electrical energy to axial motion energy by triggering the coils (19) (electromagnet) in particular order and number that are placed such that both poles can be used, and creating a magnetic field via the strong, heat resisting, fixed magnets in a particular order and number that are placed such that there is air gap for both poles (n-s) of the coil (19) .

An embodiment of the invention is mounted within the dead zone in the wheel rim.

An embodiment of the invention has high torque and power values. For example, the motor of the invention can operate in the range of 570-1500NM torque and 20-100kW power values. These values can be obtained in a cylinder area having 33cm diameter and 7cm thickness.

Particularly in order to transmit needed power to the wheel of the vehicle in the electrical vehicle propulsion systems, an embodiment of invention is comprised of a rear protection cover (1), a bearing fixing washer (2), a bearing holder flange cover (3), a stator outer connection apparatus (4) used as a bearing (7) inner seat, a rear cover connection apparatus (5) used as a bearing (7) outer seat, a rotor rear cover (6) transmitting the motion of magnets to the rotor as a result of coils (19) (electromagnet) creating a magnetic force, bearing (7), a washer (8) used between a bearing (7) and a stator, an inner magnet housing (9), inner magnets (10), a stator inner connection apparatus (11), a rotor bowl (12), a diamagnetic inner coil holder (13), a coil outer cooling sheet (14), a coil inner cooling ring (15), a coil cooling pipe (16), a cut connection apparatus (17), an joining apparatus (18), coils (19) (electromagnet), a diamagnetic outer coil holder (20), a hub (21), outer magnets (22), an outer magnet housing (23) and a rotor front cover (24) .

An embodiment of the invention more particularly comprises a rear protection cover (1) manufactured in order to fix the electrical and cooling connections, balls and washers (8), and prevent foreign objects to enter into the motor; a bearing fixing washer (2) ; a bearing holder flange cover (3) ; a stator outer connection apparatus (4) used as a bearing (7) inner seat; a rear cover connection apparatus (5) used as a bearing (7) outer seat; a rotor rear cover (6) transmitting the motion of magnets as a result of coils (19) (electromagnet) creating a magnetic force, a bearing (7), washer (8) used between a bearing (7) and stator; an inner magnet housing (9) containing miscellaneous number of magnets transmitting motion energy to the rear cover; miscellaneous number and size of inner magnets (10) that are powerful and resistant to heat; a stator inner connection apparatus (11) used as a bearing (7) inner seat; a rotor bowl (12) connecting the rotor front and rear covers to each other; a diamagnetic inner coil holder (13); a coil outer cooling sheet (14); a coil inner cooling ring (15); a coil cooling pipe (16); a cut connection apparatus (17) connecting the stator inner connection apparatus (11) to the diamagnetic inner coil holder (13); an joining apparatus (18) connecting the cut connection apparatus (17) to the diamagnetic outer coil holder (20); coils (19) (electromagnet) that are placed in miscellaneous numbers and angles; hub (21) coupling the electric motor to the wheel and body; miscellaneous number and size of outer magnets (22) that are powerful and resistant to heat; an outer magnet housing (23) containing miscellaneous number of magnets; and a rotor front cover (24) transmitting the motion of magnets to the rotor as a result of coils (19) (electromagnet) creating a magnetic force.

The detailed structural and characteristic features necessary to achieve the object of the invention are set forth in the figures and in the description with reference to these figures .

Fig. 1 is a general view of a double rotor torus type in wheel rim axial direct current motor (25) of the invention and Fig. 2 is a sectional view thereof. The in-wheel rim motor of invention used as a propulsion mechanism in electrical vehicles can operate without needing any power train. Due to its high power density and efficiency, it can reach the needed power and torque values.

As shown in Fig. 1, there are a sensor channel (1-a) and a cooling and cable channel (1-b) on the rear protection cover (1) . There is a bearing holder flange cover mounting hole (3- a) on the bearing holder flange cover (3) . Likewise, there is a rotor rear cover mounting hole (6-a) on the rotor rear cover (6) . There is a hub center section hole (24-a) , a stud hole (24-b) , wheel bowl mounting hole (24-c) on the rotor front cover (24 ) .

Fig. 2 is a sectional view of a double rotor torus type in wheel rim axial direct current motor (25) of the invention.

Fig. 3 is an exploded view a double rotor torus type in-wheel rim axial direct current motor (25) of the invention.

The wound coil (19) of the double rotor torus type in-wheel rim axial direct current motor (25) of the invention in Fig. 4 provides magnetic power to both rotors shown in Fig. 7 by means of its two poles. The arrangement, geometry and number of coils (19) are calculated with a particular algorithm. The ferromagnetic sheet (19-b) is covered with a suitable material resistant to high heat and electric stresses. The size of the enamelled wire (19-a) is calculated and it is wound around the previously covered ferromagnetic sheets (19-b) .

Fig. 5 is a sectional view of a stator (Fig. 6), a coil (19), an inner magnet (10) and an outer magnet (22), an enamelled wire (19-a) (copper coil wire) and a ferromagnetic sheet (19— b) of the double rotor torus type in-wheel rim axial direct current motor (25) .

The stator body shown in Fig. 6 is comprised of an inner coil holder (13), an outer cooling sheet (14), an inner cooling ring (15), a cooling pipe (16), a cut connection apparatus (17), a joining apparatus (18), coils (19) and an outer coil holder (20) . It is a structure containing a sensor and electric connections, in which the coils (19) are fixed between the coil holders, i.e. an inner coil holder (13) and an outer coil holder (20), and cooled by inner cooling ring (15) and outer cooling sheet (14) . The cut connection apparatus (17) comprises a cut connection apparatus mounting hole (17-a) . The outer coil holder (20) comprises outer coil holder mounting hole (20-a) .

The motor of invention provides an axial motion from the double rotor shown in Fig. 7. As a result of the energization of the electromagnets, i.e. the coils (19) by triggering the hall effect sensors located in the stator with magnetic field created by powerful inner magnet (10) and outer magnet (22) in a particular number and arrangement coupled to the rotors, an axial rotational force shown in Fig. 5 emerges. As shown in Fig. 7, the outer magnet housing (23) comprises an outer magnet housing mounting hole (23-a) .

In-wheel rim motor (25) comprises a bearing (7) coupled to a hub (21) allowing the rotor to rotate in circular motions and a bearing (7) connected to the inner rear rotor cover (6) shown in Fig. 7.

The coil holder material of inner magnet (10) and outer magnet (22) must be made of a material that is durable to high degree electric and heat isolation; flameproof; withstands mechanical loads; has dimensional stability over a wide range of temperatures; has high isolation at high frequency currents; and resistant to liquids.

The most important advantage obtained with the invention is that an axially operating, double rotor, torus type, brushless, direct drive motors that have higher power and torque values can be used in a wheel for the first time.

The double rotor and torus type structure of the invention allows to achieve a higher power density in unit area compared to both motor types.

Thanks to the invention, an axially operating, double rotor, torus type, brushless, direct current motor has been developed for use in a wheel for the first time. Therefore, higher power and torque values can be obtained with smaller volumes.

The invention relates to the propulsion and power production systems needed in industrial applications requiring large diameter, high torque, high or low rotation motion (rpm) for the production of wind power, hydroelectric and wave power, and in electrical automobiles and motorcycles, plane rotors.

They also can be used within the wheel rim in electrical automobiles, and between the motor and the power trains in hybrid vehicles.

Briefly, the invention is a torus type, brushless direct current electric motor for placement within the dead zone in the wheel rim without needing any power train, comprising a rear protection cover (1) fixing the electrical and cooling connections, balls and washers (8), and preventing foreign objects to enter into the motor; a stator body comprising hall effect sensors and respectively an inner coil holder (13), an outer cooling sheet (14), an inner cooling ring (15), cooling pipe (16), a cut connection apparatus (17), an joining apparatus (18), coils (19) (electromagnet) and an outer coil holder (20); the coils (19) fixed between an inner coil holder (13) and an outer coil holder (20), cooled by the inner cooling ring (15) and the outer cooling sheet (14), protecting the sensor and the electrical connections; a rotor front cover (24) transmitting the motion of magnets to the rotor as a result of the coils (19) creating magnetic force; a double rotor providing an axial rotational force by triggering hall effect sensors with the created magnetic field and energizing via two poles of coils (19) ; and a hub (21) allowing the rotor to rotate in circular motions, .

Description of the Figures

Fig. 1: The general view of double rotor torus type in-wheel rim axial direct current motor of the invention.

Fig. 2: The sectional view of double rotor torus type in ^¬ wheel rim axial direct current motor of the invention.

Fig. 3: The exploded view of double rotor torus type in-wheel rim axial direct current motor of the invention.

Fig. 4: The view of wound coil of double rotor torus type in ^¬ wheel rim axial direct current motor of the invention.

Fig. 5: The sectional view of stator, coil, magnet, copper coil wire and ferromagnetic material of double rotor torus type in-wheel rim axial direct current motor of the invention. Fig. 6: The view of stator of double rotor torus type in wheel rim axial direct current motor of the invention.

Fig. 7: The view of rotor of double rotor torus type in-wheel rim axial direct current motor of the invention.

Descriptions of Reference Numbers in Figures

1. Rear protection cover

1-a. Sensor channel

1-b. Cooling and cable channel

2. Bearing fixing washer

3. Bearing holder flange cover

3-a. Bearing holder flange cover mounting hole

4. Stator outer connection apparatus

5. Rear cover connection apparatus

6. Rotor rear cover

6-a. Rotor rear cover mounting hole

7. Bearing

8. Washer

9. Inner magnet housing

10. Inner magnet

11. Stator inner connection apparatus

12. Rotor bowl

13. Inner coil holder

14. Outer cooling sheet

15. Inner cooling ring

16. Cooling pipe

17. Cut connection apparatus

17-a. Cut connection apparatus mounting hole

18. Joining apparatus

19. Coils

19-a. Enamelled wire

19-b. Ferromagnetic sheet

20. Outer coil holder

20-a. Outer coil holder mounting hole

21. Hub 22. Outer magnet

23. Outer magnet housing

23-a. Outer magnet housing mounting hole

24. Rotor front cover

24-a. Hub center section hole

24-b. Stud hole

24-c. Wheel bowl mounting hole

25. Double rotor torus type in-wheel rim axial direct current motor