The technical field generally relates to methods and systems for power transfer and communications between a steering wheel and a motor vehicle, and more particularly relates to methods and systems for wireless power transfer and communications between a steering wheel and a motor vehicle.
Most motor vehicles include a steering wheel that a driver uses to guide the motor vehicle. The steering wheel is attached to a vehicle body with a wheel shaft that rotates as the steering wheel is turned. Many steering wheels also include switches and controls for operating various components in the motor vehicle. For example, some steering wheels include radio and stereo controls, controls for a cruise control, and a horn. These controls operate regardless of the position of the steering wheel. The controls require power for lighting and/or for operations, and some steering wheels include heaters or other devices with a larger power draw. Steering wheels typically include a spiral cable for electrical connections between controls on the steering wheel and the body, where the spiral cable is a hard wired connection. The spiral cable also provides power for operations in the steering wheel. The spiral cable wraps in and out of a housing as the steering wheel is turned, so the radio, stereo and other components can be controlled when the steering wheel is in any position.
The spiral cable and the associated housing are relatively large and heavy, so appropriate space and support mechanisms must be provided in the design of the motor vehicle. The spiral cable tends to wear with the repeated coiling and uncoiling of the spiral cable in the housing as the steering wheel is turned, and this wear contributes to reliability concerns. Furthermore, the spiral cable requires physical connections that can be sources of faults or shorts.
Accordingly, it is desirable to provide methods and systems for eliminating the spiral cable from the steering column. In addition, it is desirable to develop methods and systems for powering and providing communications with the steering wheel without encumbering the steering column with hard wired connections. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and the background of the invention.
Motor vehicles and methods for power and communication between a motor vehicle body and a steering wheel are provided. In an exemplary embodiment, a motor vehicle includes a steering wheel, a body, and a wheel shaft rotationally connecting the steering wheel to the body. A body power coil is positioned in the body, where the body power coil includes conductive wire. A wheel power coil is positioned in the steering wheel, where the wheel power coil includes conductive wire. The wheel power coil and the body power coil are separated by a resonance gap, and are configured to transfer electricity by magnetic resonance coupling.
A motor vehicle is provided in another embodiment. The motor vehicle includes a steering wheel, a body, and a wheel shaft rotationally connecting the steering wheel to the body. A wheel transceiver is positioned in the steering wheel, and a body transceiver is positioned in the body. The body transceiver and the wheel transceiver are configured to wirelessly communicate with each other.
A method of producing a motor vehicle is provided in yet another embodiment. The method includes attaching a steering wheel to a body, where the body includes a body power coil and the steering wheel includes a wheel power coil. The body power coil and the wheel power coil are configured to transfer electrical power from the body power coil to the wheel power coil by magnetic resonance coupling.
The exemplary embodiments will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:
The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.
Reference is made to an exemplary embodiment in
The steering wheel 14 is connected to the body 16 of the motor vehicle 10 by a wheel shaft 30, as illustrated in an exemplary embodiment in
The vehicle component 36 is configured to receive the control signal and to change operations based on the control signal. In an exemplary embodiment where the vehicle component 36 is a stereo, the vehicle component 36 (i.e., the stereo) can adjust the volume, turn on and off, change radio stations, switch between a radio function and a CD function, and/or take other actions based on one or more control signals. Some or all of the control signals for the vehicle component 36 are operated by the wheel actuator(s) 34. In an exemplary embodiment, the vehicle component 36 also includes local actuators 38 positioned on or near the vehicle component 36 that also provide control signals. In the exemplary embodiment where the vehicle component 36 is a stereo, the vehicle component 36 includes a volume control positioned on the stereo, as well as an on/off switch, a radio tuner adjustment knob, and a radio-CD function switch. The driver of the motor vehicle 10 is capable of using either the local actuators 38 or the wheel actuators 34 to send the control signal to the vehicle component 36. In alternate embodiments, the wheel actuator(s) 34 are the only controls for some vehicle components 36, and local actuators 38 are the only controls for other vehicle components 36.
The wheel actuators 34 require electrical power to generate and send the control signal. In an exemplary embodiment, electrical power is transferred to the steering wheel 14 using magnetic resonance coupling. Magnetic resonance coupling is the transfer of electrical power from one conductor (the transmitter) that produces a magnetic field to another conductor (the receiver). In an exemplary embodiment, the alternating current flows through the transmitter conductor and generates a magnetic field builds and crashes with changes in the alternating current. The receiver conductor is typically formed in a coil within the building and crashing magnetic field, where the receiver coil produces electricity as the magnetic field changes. In an exemplary embodiment, the magnetic resonance coupling uses a body power coil 40 positioned within the body 16, and a wheel power coil 42 (not visible in
In an exemplary embodiment, the body coil face 44 and the wheel coil face 48 are round, but in alternate embodiments the body coil face 44 and/or the wheel coil face 48 are square, rectangular, oval, or other shapes. A square or rectangular shape for the body and/or wheel coil face 44, 48 can aid in power transfer if the body power coil 40 and wheel power coil 42 are partially mis-aligned. The body and wheel power coils 40, 42 have a body coil maximum distance 52 and a wheel coil maximum distance 54, respectively, where the body and wheel coil maximum distance 52, 54 is the maximum distance measured across the body and wheel coil face 44, 48, respectively. In an embodiment with a round body coil face 44, the body coil maximum distance is the diameter of the body coil face 44. In an embodiment with a square body coil face 44, the body coil maximum distance 52 is the diagonal of the square, and so forth.
The body power coil 40 and the wheel power coil 42 are positioned adjacent to each other, such that the body coil face 44 is positioned adjacent to and at least partially overlapping the wheel coil face 48. Alternating current electricity provided to the body power coil 40 (i.e., a transmitter coil), induces an electrical alternating current in the wheel power coil 42 (i.e., a receiver coil). The wheel power coil 42 and the body power coil 40 are positioned near each other, but are not in electrical communication, wherein “electrical communication,” as used herein, means connected by one or more electrical conductors. As such, no wire, bar, bus, or other electrical conductor contacts both the wheel power coil 42 and the body power coil 40. A resonance gap 58 is the distance between the body power coil 40 and the wheel power coil 42, and the resonance gap 58 is from about more than 0 centimeters to about the lesser of the body coil maximum distance 52 and the wheel coil maximum distance 54 in an exemplary embodiment. In other embodiments, the resonance gap 58 is from about more than 0 centimeters to about ½ or about ¼ of the lesser of the body and wheel coil maximum distance 52, 54. The body and wheel power coils 40, 42 can be as close as possible as long as there is no electrical communication (i.e., an electrical short) between the two. In some embodiments, the body power coil 40 and/or the wheel power coil 42 are positioned concentrically around the wheel shaft 30 and the steering axis 32, but other positions are also possible. The electricity produced in the wheel power coil 42 is used as needed within the steering wheel 14, such as for producing a control signal or for powering a steering wheel heater (not illustrated in
In some embodiments, the body power coil 40 is printed on a body printed circuit board 62, as illustrated in
Referring to an exemplary embodiment illustrated in
Reference is made to an exemplary embodiment in
A body controller 76 is configured to communicate with one or more of the inverter 60, the body amplifier 70, the body communication board 74, and the communication coil 72. In various embodiments, the body controller 76 includes any type of processor or multiple processors, integrated circuits such as a microprocessor, or any suitable number of integrated circuit devices and/or circuitry working in cooperation to accomplish the tasks of the body controller 76. The body controller 76 executes one or more programs that are stored within a body controller memory 78 in an exemplary embodiment. In one example, the body controller memory 78 saves various other data as well, such as information for other processes within the motor vehicle 10. In various embodiments, the body controller 76 includes, or has access to, any type of body controller memory 78, including but not limited to random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), and non-volatile random access memory (NVRAM).
The wheel power coil 42 and the wheel impedance coil 66 are in communication with a wheel controller 80 in an exemplary embodiment illustrated in
The use of magnetic resonance coupling and wireless communication systems eliminate the need for a spiral cable or another hard wired electrical connector between the body 16 and the steering wheel 14, so the motor vehicle 10 is free of a steering wheel power wire (not illustrated) or a steering wheel signal wire (not illustrated) that travel from the body 16 to the steering wheel 14. The wireless transfer of power and control signals reduces the number of moving parts in the steering wheel system compared to a steering wheel with a spiral cable. The reduction in the number moving parts can improve reliability and simplicity while reducing weight and bulk. Many of the components for the magnetic resonance coupling and the wireless communication are available on circuit boards of one type or another, and circuit boards typically require less space and weight than a spiral cable and the associated hardware. Therefore, the wireless transfer of power and communications also reduces bulk and weight in many embodiments.
While at least one exemplary aspect has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary aspect or exemplary aspects are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary aspect of the invention. It is to be understood that various changes may be made in the function and arrangement of elements described in an exemplary aspect without departing from the scope of the invention as set forth in the appended claims.