JPS588919A - Combustion control circuit - Google Patents

Abstract

PURPOSE:To stop the post-purge function when reignition operation is performed at the post-purge, by providing a circuit which, when a second switch is turned ON at the post-purge, outputs a signal for resetting a post-purge circuit. CONSTITUTION:At the steady operation, when a first switch 2 and the second switch 5 are opened to stop the operation, the first and second switches 2, 5 are opened one after the other to cause the electric current to a safety timer 18, a flame detecting circuit 16, etc. to be turned OFF, and a post-purge timer 27 is actuated to cause the electric current to pass through a post-purge relay 26 so that post-purge is carried out. During this post-purge, if the first and second switches 2, 5 are closed to operate reignition, the electric current to the post- purge relay 26 is stopped simultaneously with the closing of the second switch 5, and a prescribed ignition action is carried out. Thus, when reignition operation is performed at the post-purge, the post-purge function can be stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustion control circuit for a combustor equipped with a post-purge function, and in particular, an object of the present invention is to stop the post-purge function during a re-ignition operation during post-purge.

For stoves, etc., a post-purge circuit is installed that rotates the blower for a predetermined period of time after extinguishing the fire, in order to prevent equipment damage due to heat accumulation after combustion has stopped.
In many of the devices equipped with the above-mentioned post-purge circuit, even if a re-ignition operation is performed at the time of post-purge, the ignition operation does not occur until the post-purging time has elapsed, making them inconvenient to use.

The present invention has been made in view of the above point ε, and will be explained below with reference to FIG. 1.

(1) is a commercial power source, which is connected to a convection fan motor (3), a direct current source (4), etc. via a first switch (2).

In addition, the DC power supply (4) is connected to the second switch (5), and the IQε first switch via the switch element (6) using a Tunster.
The first relay (Rysu (9)) and the second relay (myri1) are connected to the rear stage of the switchboard (2), and the relay contact (9) is connected between the nine igniter (7) and the solenoid valve (8). are connected in series via the drive T, Tunister, and A.
The first and second switches (2) and (5) are opened and closed in conjunction with the rotation of the operating shaft, etc., and the closing switch (5) of the first switch (2) is closed, and the j12 switch (5) is closed. It is configured so that Kaisei Apprentice 1 Suite (2) is closed.

The above 1. The first reset circuit consists of a circuit similar to a Nyristor equivalent circuit by interconnecting transistors A to S connected in parallel to the second relay (9) and the like.

The pace of the transistor α fathom is the driving transistor 0.
Connected to the pace of.

! A flame detection circuit, a pre-purge timer 1''r), a safety timer α, and a forced ignition timer 0 are installed between the second switch (5) shown in θ and the switching element 163, and the output of the flame detection circuit is set at the pace of the transistor. and its collector is connected to the base of the driving transistor 2 through a resistor (21), and is connected to the base of the 9 transistors 4 and the collector of the F transistor U facing the first reset circuit via the diode (2), and the transistor The collector of is the safety timer Ql
as well as the input side of the 19th set of transistors W&-
Connected to the collector of IS. The output of the safety timer is connected to the pace of the switching element (6), and this pace is connected to the collector of the transistor (2), which is connected to the output of the pre-purge timer. The output of the following 0 forced ignition timer 0 is connected to the pace of the 111th generation driving transistor I.

After closing the first and second switches (2) and (5), the output of the pre-purge timer 0 turns on the transistor (to) and turns off the switching element (6), causing the pre-purge &>
Do something. When the pre-purge time elapses T, the output of the pre-purge timer is '! becomes I & low, turning off the transistor and turning on the switching element (63).
The I1 ignition timer a9 operates, and its output turns on the driving transistor I, turning on the first ignition timer a9. 2nd relay (RysuC
Transistor I turns off at low output due to the predetermined time opening of 0 forced ignition timer 4, which energizes Rysu(9)-.
The power to I (I) (9) will be stopped, but the 1ll
The low output of the flame detection circuit αe caused by the I fire turns off the transistor, and turns on the transistor a4, which continues to energize the second relay (my relay).Then, the flame detection circuit (18 At the output, the transistor σ41 (15) of the first reset circuit aJ is turned on to set it, and the input of the safety timer (Ls is set to low to stop its operation).

Furthermore, a post purge timer (R
y) A post-purge circuit consisting of a post-purge timer (2), etc., and i10 first reset circuits αJ and I.
! A second reset circuit (2) formed by interconnecting transistors @O1e and an abnormality reset circuit diagram are connected to the same circuit configuration. and the post purge timer (
2) has its output connected to the pace of the transistor (to) whose collector is connected to the pace of the driving transistor (to) via the diode (g), and the input (b)
A diode C (
It is connected via l. The collector of the voltage detection transistor (sub) is connected to the collector of the transistor (to) of the second reset circuit □□□ via a diode chain. The collector of this transistor (to) is connected to the collector of the transistor C2 of the abnormal reset circuit (to) through a diode (4η).This collector is also connected to the switching element (6) through a diode (0).
), connect the base to the first reset circuit's transistor a◆, the collector, and the flame detection circuit αG.
It is connected to the collector of the misfire transistor, which is connected to the output via the diode (c). (Incorporated) is a transistor for inhibiting setting, whose collector is connected to the output of the flame detection circuit αG via the pace of the transistor of the j12 reset circuit (to) and the diode 4-, and the pace is connected to the output of the pre-barge timer aη. , turns on the transistor (to) at the time of prepurge, and turns off the second transistor at that time.
Prohibits setting of the reset circuit (to). An alarm pad is connected to the emitter of transistor C (υ) of the abnormality reset circuit (to).

Therefore, during pre-purge after closing the second switch (5), the set prohibition transistor is turned on at the output of the pre-purge timer to prohibit setting of the second y-set circuit (to). Is the pre-purge timer 11 after the pre-purge time has elapsed? ) becomes low, or when the cupana is ignited and the output of the flame detection circuit is only one, the above-mentioned 15th set circuit (13th cella [accompanied by the second reset circuit (to)) is activated. Transistor @ (to) is turned on and set. As a result, bias current flows from the 25th set circuit (to) to the driving transistor (c), but the pressure detection transistor (to) is also turned on at 1. Since the bias current is bypassed through the diode (43), when the second switch (2) is opened in the sumo wrestler ε state, the voltage detection transistor (2) is turned off and the 9 drive transistor (2) is turned off. ) is turned on, the post purge relay (11) is energized, connected in parallel to the first switch (2), and the contact 97 -
, and the post-purge timer wtJ starts operating.

Furthermore, during the above-mentioned post-purge, the first. Second switch (2) (
5) is closed and a re-ignition operation is performed, one voltage detection transistor (to) is activated as the second switch (5) is closed.
is turned on, the input (to) of the purge timer (to) is set low, and this is set again. Other flame detection circuit 1・,
Since the purge timer a11 and the like are initially set to 5 when the second switch (5) is opened, a predetermined rate of rinsing operation is performed when the second switch (5) is closed.

In addition, in the event of a misfire, the output of the flame detection circuit goes high, which turns on the misfire transistor 4, which turns on the transistor (to) and switching element (6) of the abnormality reset circuit.
Turn off; set the normal reset circuit a4t, and then
- while operating the first. The energization to the 25th relay (9)- is stopped. Then, the misfire transistor is turned on, blocking the bias of the transistor (through) through the diode θη, and thereby the post-purge relay (through).
Turn off.

FIG. 2 is a time diagram of the circuit described above, relative to the output level of each contact or circuit, so that during ignition operation, the first. The second switches (2) and (5) are closed in sequence, and thereby the pre-purge operation an is activated, and the output of the safety timer α and the forced ignition timer 11 are invalidated to perform the pre-purge operation. When the part T is ignited, the output of the flame detection circuit (18) becomes low and the output of the safety timer is held at ^A, and the second relay (
9 is energized, the solenoid valve (8) is opened, and steady operation begins.

In the case of a misfire during the process, the flame detection circuit will not come out properly],
The output of the safety timer α is set low to stop the power supply to the second switch, and this state continues until the first and second switches (bar 5j) are opened.During normal operation, the first and second switches +2) If (5) is opened and a stop operation cannot be performed, the first. The second switches (2-bar 5) are sequentially opened to stop energizing the safety timer (l, flame detection circuit w!1m1, etc.), and the post-purge timer is activated to energize the post-purge relay (to). A post purge is performed.

During this post-purge, when the first and second switches t (2-bar 5) are closed and a re-ignition operation is performed, the post-purge relay (to) is energized at the same time as the second switch (5) is closed. The engine is stopped and a predetermined ignition operation is performed.

As described above, the combustion control device according to the present invention has a second switch connected in series after the first switch to which the top purge relay contacts are connected in parallel.

A post purge circuit is constructed between the first and second switches, and a reset circuit is provided downstream of the second switch to output a reset signal for the post purge circuit KC when the second switch is closed during the BoXJ purge. If a re-ignition operation is performed during post-purge, the post-purge circuit will stop operating.

With no post purge, the specified ignition operation can be performed immediately, making it extremely easy to use.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a combustion control circuit according to the present invention. Figure 2 shows the same timing data. (2)・-1st switch, (5)-2nd switch, Jin J
・-1st y set circuit, αG... flame detection circuit, @-・
・Bost purge circuit, @・-2nd reset circuit, C34
−Abnormal reset circuit・

Claims (1)

[Claims] (1) A second switch is connected in series after the first switch with post-purge relay contacts connected in parallel, and a post-purge circuit is configured between the first switch and the second switch with 10 arrangement, and the second When the second switch is turned on during the post-purge after the switch, @boost purge time l! A combustion control circuit comprising a reset circuit that outputs a reset signal for the combustion control circuit.