Inductive heated injector using a three wire connection
View Patent ↗A fuel injector assembly includes a first coil driven by a direct current driver and a second coil driven by an alternating current driver where both the first coil and the second coil share a common connection to reduce the number of external terminal connections. The second coil generates a second magnetic field that is utilized to heat a component in thermal contact with the fuel flow that in turn heats fuel before exiting the fuel injector.
1. A fuel injector assembly comprising:
a first coil for generating a first magnetic field responsive to a first signal;
a second coil generating a second magnetic field responsive to a second signal;
a first driver including a first lead electrically connected to the first coil;
a second driver including a second lead electrically connected to the second coil;
a common lead connected to both the first coil and the second coil; and
a component within thermal contact with a fuel flow path that is heated responsive to the second magnetic field generated by the second coil.
2. The assembly as recited in claim 1 , wherein the first signal comprises a direct current signal and the second signal comprises an alternating current signal.
3. The assembly as recited in claim 2 , including a high pass filter preventing alternating current from interfering with the direct current to the first coil.
4. The assembly as recited in claim 2 , wherein the first signal and the second signal operate independent of each other.
5. The assembly as recited in claim 1 , including an armature movable responsive to the first magnetic field for controlling a flow of fuel, wherein a portion of the armature is inductively heated by the second magnetic field.
6. The assembly as recited in claim 5 , including an armature movable within a valve body that defines an annular fuel flow channel between the armature and the tube.
7. The assembly as recited in claim 1 , wherein the second magnetic field induces hysteretic and eddy current loses that heat the component within the fuel flow path.
8. The assembly as recited in claim 1 , wherein the common lead comprises a ground connection.
9. The assembly as recited in claim 1 , wherein the common lead comprises a connection to a common voltage buss.
10. A method of heating fuel comprising the steps of:
a) generating a first magnetic field in a first coil responsive to a first signal from a first driver;
b) generating a second magnetic field in a second coil responsive to a second signal from a second driver;
c) attaching the first coil and the second coil to a common connection; and
c) heating a component within a flow of fuel with the second magnetic field generated by the second coil.
11. The method as recited in claim 10 , wherein the first signal is a direct current signal and the second signal is an alternating current.
12. The method as recited in claim 10 , wherein a high pass filter is disposed on the common connection between the first coil and the second coil for preventing the alternating current signal to the second coil from interfering with the direct current to the first coil.
13. The method as recited in claim 10 , including the step of controlling the flow of fuel with the first magnetic field generated by the first coil.
14. The method as recited in claim 10 , including the step of controlling movement of an armature between an open and closed position.
15. The method as recited in claim 10 , wherein said step c, comprises generating a time varying magnetic field with the alternating current signal that acts on the component within the flow of fuel with the time varying magnetic field.
16. The method as recited in claim 10 , wherein the common connection comprises a connection to a common ground.
17. The method as recited in claim 10 , wherein the common connection comprises a connection to a common voltage buss.
18. The method as recited in claim 15 , wherein the component within the fuel flow comprises an armature movable responsive to the first magnetic field that is heated by the second magnetic field.