US 4,280,184 A · Burner flame detection

Abstract

Method and apparatus for evaluating the quality of a flame in response to outputs from a flame sensor. The present invention includes a method and apparatus in which output pulses from a flame sensor are continuously counted.The number of pulses is accumulated over a time interval of a predetermined length and compared with a threshold value. The accumulated total is continuously updated to reflect the pulses received over the previous time interval to effectively provide a moving time-window of a fixed length over which pulses from the flame sensor are accumulated. Other additional checks may be made to ascertain that a flame is present, including the time over which no pulses are detected and a long-term average of the number of pulses. A preferred embodiment disclosed in which numerous self-checking features are incorporated, and which includes a novel bar-graph type of display for displaying flame quality and diagnostic information.

Claims37

Dependent claims

A method for providing a signal representative of the quality of a flame in a burner system of the type including a burner for producing a flame and a flame sensor responsive to the burner flame for providing signal pulses representative of the flame, the method comprising the steps of:

defining a series of successively-occurring time intervals;
counting the number of pulses produced by the flame sensor during each interval;
storing the number of pulses produced during each of a selected number of preceding intervals, the duration of said selected number of intervals defining a first period of time;
periodically determining the number of pulses produced during the preceding first period of time to define a total number equal to said number of pulses produced during the preceding first period of time;
comparing said total number with a threshold value to determine when said total number is below the threshold value and providing a signal representative thereof.

2 more elements

A flame analyzer for providing a signal representative of the quality of a flame in a burner system of the type including a burner for producing a flame and a flame sensor responsive to the burner flame for producing signal pulses representative of the flame, the flame analyzer comprising:

means for defining a series of successively-occuring time intervals;
means for counting the number of pulses produced by the flame sensor during each interval;
a memory;
means, responsive to the counting means, for storing the number of pulses produced during each of a selected number of preceding intervals, the duration of said selected number of intervals defining a first period of time;
means for determining the number of pulses produced during the preceding first period of time to define a total number equal to the number of pulses produced during the preceding first period of time;
means for comparing said total number with a threshold value to determine when said total number is below the threshold value and for providing an output signal representative thereof which represents the flame quality.

3 more elements

Dependencies are inferred from the claim text.

Burner flame detection

Life of this patent

Burner flame detection

Life of this patent

Abstract

Claims37