Low cost high speed spark voltage and flame drive signal generator
AssigneeHoneywell International Inc.
InventorsBrent Chian, Jonathan McDonald, Norm Planer
Life of this patent
Estimating the term…
Abstract
A system for generating a high DC voltage for a spark to ignite a flame in a combustion device, and a high AC voltage for a flame rod to sense a flame in the device, from a low voltage for combustion device control. The system may be an inexpensive mechanism.
Claims20
A spark voltage and flame rod voltage generator for a combustion device, comprising:
- a driver for receiving a low-voltage supply and a control signal;
- an inductive-capacitive (LC) circuit connected to an output of the driver, for providing a flame rod voltage;
- and
- a rectification-capacitive circuit connected to an output of the LC circuit for providing a spark voltage.
A method for generating a spark voltage and a flame rod voltage for a combustion device, from a low voltage supply of the combustion device, comprising:
- providing an electrical supply having a first voltage to a driver circuit;
- providing a pulse width modulation (PWM) signal having a duty cycle and a frequency to the driver circuit for driving an inductor-capacitor (LC) circuit with the PWM signal;
- adjusting the pulse width and frequency of the PWM signal to obtain a near sinusoidal signal having a second voltage at an output of the LC circuit;
- rectifying the near sinusoidal signal having the second voltage into a direct current (DC) signal;
- and
- charging up a capacitor with the DC signal for a spark voltage.
A spark voltage and flame rod voltage generator for a combustion device, comprising:
- an inductor-capacitor (LC) circuit;
- a driver for driving the LC circuit with a pulse width modulated (PWM) signal;
- a spark voltage circuit connected to an output of the LC circuit;
- a voltage sensing circuit connected to the output of the LC circuit;
- a flame sensing circuit connected via a direct current (DC) blocking device to the output of the LC circuit;
- and
- a flame rod connected via the DC blocking device to the output of the LC circuit.
The generator of 16, wherein:
- the generator uses a power supply having a first voltage;
- the spark voltage circuit is for providing a second voltage;
- the output of the LC circuit has a third output voltage;
- and
- each of the second and third voltages is greater than the first voltage.
Dependencies are inferred from the claim text.