Wireless in-wheel electric assemblies with integrated in-wheel cooling and vehicles incorporating the same

• US 10,381,901 B2
• Filed: 05/12/2017
• Issued: 08/13/2019
• Est. Priority Date: 05/12/2017
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Zhou, Feng, Dede, Ercan Mehmet, Ukegawa, Hiroshi N., Miyagi, Kyosuke
• Primary Examiner(s): Nguyen, Tran N
• Application Number:
  US15/594,088
• Publication Number:
  US 20180331601A1
• Time in Patent Office: 823 Days
• CPC Class Codes: B60K 11/04 Arrangement or mounting of radiators, radiator shutters, or radiator blinds B60K11/085 takes precedence
• CPC Class Codes: B60K 11/06 with air cooling
• CPC Class Codes: B60K 2007/0038 the motor moving together with the wheel axle
• CPC Class Codes: B60K 2007/0092 the motor axle being coaxial to the wheel axle
• CPC Class Codes: B60K 7/0007 the motor being electric
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2220/44 Wheel Hub motors, i.e. integrated in the wheel hub
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 50/52 characterised by DC-motors
• CPC Class Codes: B60Y 2400/602 DC Machines
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02K 11/33 Drive circuits, e.g. power electronics H02K11/38 takes precedence
• CPC Class Codes: H02K 7/1846 structurally associated with wheels or associated parts dynamos arranged in the wheel hub of cycles B62J6/12
• CPC Class Codes: H02K 9/06 with fans or impellers driven by the machine shaft
• CPC Class Codes: H02K 9/197 in which the rotor or stator space is fluid-tight, e.g. to provide for different cooling media for rotor and stator
• CPC Class Codes: H02K 9/227 Heat sinks
• CPC Class Codes: H02P 27/06 using dc to ac converters or inverters H02P27/05 takes precedence
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A wireless in-wheel electric motor assembly having a wheel, an electric motor disposed within the wheel, the electric motor including a stator and a rotor, a receiving coil disposed within the wheel and operable to receive wirelessly transmitted energy, a first converter disposed within the wheel, electrically coupled to the receiving coil and operable to convert the wirelessly transmitted energy from the receiving coil into direct current, an inverter circuit disposed within the wheel, electrically coupled to the conversion circuit and the electric motor, and operable to power the electric motor. The wireless in-wheel electric motor assembly further includes a cooling system disposed within the wheel that includes a micro pump operable to pump coolant, a fluid line operable to pass the coolant proximate at least one of the conversion circuit and the inverter circuit, and a heat exchanger operable to receive heated coolant and dissipate heat to the environment.

Claims

1. A wireless in-wheel electric motor assembly comprising:

a wheel;

an electric motor disposed within the wheel, the electric motor comprising a stator and a rotor;

a receiving coil operable to receive wirelessly transmitted energy, wherein the receiving coil is disposed within the wheel;

a first conversion circuit electrically coupled to the receiving coil and operable to convert the wirelessly transmitted energy from the receiving coil into direct current, wherein the first conversion circuit is disposed within the wheel;

an inverter circuit electrically coupled to the first conversion circuit and the electric motor, wherein the inverter circuit is operable to power the electric motor and is disposed within the wheel; and

a cooling system disposed within the wheel, the cooling system comprising;

a micro pump operable to pump coolant;

a fluid line operable to pass the coolant proximate at least one of the first conversion circuit and the inverter circuit; and

a heat exchanger operable to receive heated coolant and dissipate heat to an environment.

2. The wireless in-wheel electric motor assembly of claim 1, further comprising a second conversion circuit electrically coupled to the first conversion circuit and the micro pump, wherein the second conversion circuit is operable to power the micro pump and is disposed within the housing.

3. The wireless in-wheel electric motor assembly of claim 1, further comprising a fan configured to force air to flow across the heat exchanger.

4. The wireless in-wheel electric motor assembly of claim 3, wherein the fan is selectively powered based on at least one of a rotational velocity of the wheel, a temperature of the coolant, a temperature of the electrical components of the system, an electrical output of the motor, and a mechanical output of the motor.

5. The wireless in-wheel electric motor assembly of claim 1, further comprising a hubcap having a fan blade shape such that rotation of the hubcap forces air across one or more of the heat exchangers to convect heat out of the coolant.

6. The wireless in-wheel electric motor assembly of claim 1, wherein the cooling system supplies coolant to a stator of the in-wheel electric assembly to cool the stator.

7. The wireless in-wheel electric motor assembly of claim 1, wherein the cooling system further comprises a manifold plate comprising an inner face and an outer face, the outer face including a pair of concentric cooling channels including an outer channel and an inner channel.

8. The wireless in-wheel electric motor assembly of claim 7, wherein the pair of concentric cooling channels are fluidly coupled to one or more coolant supply channels and one or more coolant return channels through one or more stator irons of the stator within the wheel through a pair of openings in the manifold plate.

9. The wireless in-wheel electric motor assembly of claim 8, wherein

each of the one or more stator irons comprises the coolant supply channel and the coolant return channel passing through a width of the stator iron;

and

the coolant supply channel and the coolant return channel are coradial with the outer channel and the inner channel of the outer face of the manifold plate, are fluidly coupled thereto, and the individual coolant supply and coolant return channels are fluidly coupled by a redirection feature at the end of the coolant supply and the coolant return channels opposite the manifold plate.

10. A vehicle comprising:

one or more batteries;

a transmitting coil electrically coupled to the one or more batteries and operable to transmit wirelessly transmitted energy; and

a wireless in-wheel electric motor assembly comprising;

a wheel;

an electric motor disposed within the wheel, the electric motor comprising a stator and a rotor;

a receiving coil operable to receive wirelessly transmitted energy from the transmitting coil;

a first conversion circuit electrically coupled to the receiving coil and operable to convert the wirelessly transmitted energy from the receiving coil into direct current, wherein the first conversion circuit is disposed within the wheel;

an inverter circuit electrically coupled to the first conversion circuit and the electric motor, wherein the inverter circuit is operable to power the electric motor and is disposed within the wheel; and

a cooling system comprising;

a micro pump operable to pump coolant;

a fluid line operable to pass the coolant proximate at least one of the first conversion circuit and the inverter circuit; and

a heat exchanger operable to receive heated coolant and dissipate heat to an environment.

11. The vehicle of claim 10, wherein the wireless in-wheel electric motor assembly further comprises a second conversion circuit electrically coupled to the first conversion circuit and the micro pump, wherein the second conversion circuit is operable to power the micro pump and is disposed within the housing.

12. The vehicle of claim 10, wherein the wireless in-wheel electric motor assembly further comprises a fan configured to force air to flow across the heat exchanger.

13. The vehicle of claim 12, wherein the fan is selectively powered based on at least one of a rotational velocity of the one or more wheels, a temperature of the coolant, a temperature of the electrical components of the system, an electrical output of the motor, and a mechanical output of the motor.

14. The vehicle of claim 10, wherein the wheel further comprises a hubcap having a fan blade shape such that rotation of the hubcap forces air across one or more of the heat exchangers to convect heat out of the coolant.

15. The vehicle of claim 10, wherein the cooling system supplies coolant to one or more stators of the one or more in-wheel motor assemblies to cool the one or more stators.

16. The vehicle of claim 10, wherein the cooling system further comprises a manifold plate having an inner face and an outer face, the outer face comprising concentric cooling channels that are fluidly coupled to one or more coolant supply channels and one or more coolant return channels through one or more stator irons of the stator, wherein the concentric cooling channels are configured to supply coolant to the one or more coolant supply channels of the stator and receive heated coolant from the one or more coolant return channels of the stator.

17. The vehicle of claim 16, wherein the one or more coolant supply channels and the one or more coolant return channels are fluidly coupled by a redirection feature at an outer end of the coolant supply and the coolant return channels that is opposite the manifold plate.

18. The vehicle of claim 17, wherein the coolant supply channels and the coolant return channels form parallel channels within the one or more stator irons.

19. The vehicle of claim 10, further comprising a power electronics plate, wherein at least the first converter and the inverter circuit are supported by the power electronic plate, and the cooling system comprises cooling lines that fluidly couple the first converter and the inverter circuit with the radiator.

20. The vehicle of claim 19, further comprising a manifold plate having an inner face and an outer face, the outer face including concentric cooling channels that are fluidly coupled to the cooling system and configured to supply coolant to the stator and receive heated coolant from the stator, wherein the cooling lines of the power electronics plate and the cooling channels of the manifold plate are configured in series, such that coolant flows through the cooling lines before flowing through the cooling channels.