JPH0359316A - Safety control device of combustion apparatus - Google Patents

Abstract

PURPOSE:To improve usability by executing prepurge again or by executing the prepurge or preignition in continuation, when a time of continuation or a time of addition of a false flame signal generated on detection of a false flame is shorter than a prescribed reference time. CONSTITUTION:A false flame determinator 6 comprises a time detecting means which detects a time of continuation of a false flame signal generated on detection by a flame sensor 2 or a time of addition of the time when the false flame signal is obtained, in a period of prepurge or preignition, and a comparing means which compares the detected time with a prescribed reference time. A display device 7 is subjected to a display control by a sequence controller 3 and conducts a prescribed display such as an alarm display. A setting unit 8 for setting control modes makes setting beforehand as to whether a return is made to the prepurge and restart is executed or whether an operation of the prepurge or the preignition is continued as it is when the time detected by the time detecting means is shorter than the prescribed reference time. Accordingly, a labor of executing the restart after lockout, an alarm, etc. are reset is saved and usability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a combustion equipment safety arm device for safely controlling boilers, furnaces, and other general combustion equipment.

[Conventional technology]

In a conventional combustion device in which the main burner is ignited through a predetermined combustion sequence such as pre-purge or pre-ignition, a pseudo flame is generated during the pre-purge or pre-ignition period. Then, almost at the same time as the occurrence is detected, the device is locked out, or the bimetal heater is heated, and an alarm buzzer or the like is immediately sounded.

[Problem to be solved by the invention]

Conventional combustion equipment is locked out or an alarm is generated even if a false flame occurs for a very short time during the pre-purge or pre-ignition period as described above.
Each time, it is necessary to manually lock out or reset the alarm before restarting the system, which is very inconvenient to use.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to obtain a safety control device for a combustion device that is easy to use by performing predetermined processing depending on the duration of a pseudo flame.

[Means to solve the problem]

The safety control device for a combustion device according to the present invention performs the pre-purge again or continues the pre-purge or pre-ignition when the continuous time or addition time of the pseudo-flame signal that detected the pseudo-flame is shorter than a predetermined reference time. This is how it was done.

[For production]

The safety control device for a combustion device according to the present invention does not lock out or issue an alarm when a pseudo flame occurs for a short period of time, and returns to pre-purge again or restarts the currently underway pre-purge or pre-ignition. It will continue as is.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a combustion device, 2 is a flame sensor provided in the combustion device 1 as means for detecting a false flame, and 3 is an operation control device for the combustion device 1 according to a predetermined combustion sequence, as well as other predetermined controls. 4 is a pre-purge timer that is operated during the pre-purge period according to instructions from the sequence controller 3; 5 is a pre-ignition timer that is operated during the pre-ignition period according to instructions from the sequence controller 3; 6 is a pseudo flame detector. A time detection means for detecting an additional time obtained by adding the time during which the pseudo flame signal detected by the flame sensor 2 continues or the time during which the pseudo flame signal is obtained during the pre-purge or pre-ignition period, and this time detection means. and comparison means for comparing the detected time with the detected time.

7 is a display device that displays a predetermined display such as an alarm display under display control by the sequence controller 3;
is a setting device for setting the control mode, and when the time detected by the time detection means is shorter than the predetermined reference time, it returns to pre-purge and restarts, or continues to operate pre-purge or pre-ignition. Set in advance whether to do so.

Next, the operation will be explained with reference to the flowchart shown in FIG.

First, in step STI, the control mode of the device is set to restart mode or operation continuation mode using the setting device 8. Next, the process proceeds to step ST2, where it is checked whether pre-purge or pre-ignition is currently being performed in the combustion device I.

If no pre-purging or pre-ignition is performed, the following sequence is executed. If the pre-purge or pre-ignition is being performed, the process proceeds to step ST3, where it is checked whether a false flame signal is detected from the flame sensor 2 during the operation period of the pre-purge timer 4 or the pre-ignition timer 5. If the pseudo flame signal is not detected, the process returns to step ST2, and if it is detected, the process proceeds to step ST4.

In this step ST4, the time detection means of the pseudo flame determination device 6 detects an additional time obtained by adding the time during which the pseudo flame signal continues or the time during which the pseudo flame signal is obtained. Further, the comparison means compares the time detected by the time detection means (hereinafter referred to as duration time) with a predetermined reference time (for example, 5 seconds). If the duration is shorter than the reference time, the process returns to step ST2. In this step ST2, if the control mode set by the setting device 8 is the restart mode, the process returns to the pre-purge and is restarted from the pre-purge. Further, when the set control mode is the operation continuation mode, the currently performed pre-purge or pre-ignition continues to be performed.

Further, if it is determined in step ST4 that the above-mentioned duration time exceeds the reference time, the above-mentioned additional time is transferred to the memory as necessary in step ST5, and then the process proceeds to step ST6, where a predetermined lockout is performed. While performing the processing, a warning is displayed on the display device 7, and furthermore, the entire load is stopped.

Note that if you want to restart the system after this, you can do so by resetting the lockout and alarm after confirming that there are no other abnormalities.

According to the above, if a false flame occurs during pre-purge or pre-ignition and disappears within 5 seconds, the pre-purge will be restarted or the pre-purge or pre-ignition that is currently being performed will be restarted. will continue to be carried out. If the false flame continues for more than 5 seconds, predetermined measures such as lockout and warning will be taken immediately.

〔Effect of the invention〕

As described above, according to the present invention, when the pseudo flame disappears within a certain period of time, it automatically returns to the pre-purge and restarts, or the pre-purge or pre-ignition continues as it is, which is different from the conventional method. To improve usability by eliminating the need for lockout or alarm even if a false flame occurs in a short period of time, such as by eliminating the trouble of restarting after resetting lockout, alarm, etc. It produces the effect that can be achieved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a safety control device for a combustion device according to an embodiment of the present invention, and FIG. 2 is a flowchart showing the operation of the device. 1 is a combustion device, 2 is a flame sensor, 3 is a sequence controller, 4 is a pre-purge timer, 5 is a pre-ignition timer, and 6 is a pseudo flame detector.

Claims (1)

[Claims] A detection means for detecting a pseudo flame generated during a pre-purge or pre-ignition period, and a time for detecting the sum of the time during which the pseudo flame signal detected by the detection means continues or the time during which the pseudo flame signal is obtained. a detection means; a comparison means for comparing the time detected by the time detection means with a predetermined reference time; A safety control device for a combustion device, comprising: a sequence controller for controlling the combustion device so as to perform the process again or to continue performing pre-purge or pre-ignition.