JPS60221619A - Burning control device - Google Patents

Abstract

PURPOSE:To perform the after-purge by utilizing a burning control circuit having no after-purge faculty by a method wherein a CR timer requiring designated time for discharging is provided, the timer is charged by a blower driving signal and the discharging thereof is started by a blower stopping signal. CONSTITUTION:When the temperature of a load is raised by burning higher than the designated temperature, the output level at terminals 2a, 2b and 2c of an integrated circuit 2 is made Hi level, then the operation of all units is made stop. Thereby, a transistor 13 is made OFF, the electric charge of a capacitor 10 is discharged, a comparator 11 continues at Hi level condition during the designated time until the positive input terminal becomes lower than the negative input terminal. Meanwhile, because of the Hi level at output terminals 2b, 2c, the transistor 13 is made OFF. Consequently, the transistor 13 is made ON again, a relay 3 is made ON, accordingly, the after-purge can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustion control device. In particular, existing combustion control systems that do not have an afterbarge sequence f
It is an object of the present invention to provide a combustion control device that can perform all afterverging operations using t'&.

The present invention provides a C
An R timer is provided, and after-purging is performed by the charge signal of the CR timer.

Below, a case @VC in which the present invention is applied to a pulse combustor will be explained.

A pulse combustor is a combustor that generates flame intermittently, that is, in pulses, unlike a general combustor that generates a combustion flame continuously over time. The pulse combustor is
There are various methods, but for example, a valve that controls the supply of gaseous fuel and air to the combustion chamber, a combustion chamber, and a combustion chamber are provided to generate air column vibration at a predetermined period. The exhaust pipe is good. Generally, the combustion chamber and exhaust pipe serve as a heat exchanger.

Its operation is to supply fuel and air to the combustion chamber through valves,
When it is ignited with an igniter, it explodes and burns, and the resulting pressure closes the valve, while the combustion gases are exhausted through the exhaust pipe. This discharge creates a negative pressure in the combustion chamber, the valve opens, and fuel and air are sucked in. The vibration of the air column caused by the combustion chamber and the exhaust pipe moves the residual combustion flame or high-temperature gas in the exhaust pipe into the combustion chamber. The inhaled fuel explodes and burns using this as an ignition source. This pressure rise causes the previous combustion exhaust gas to be discharged. This is considered as one cycle, and this cycle is continuously repeated. In other words, combustion occurs intermittently, that is, in pulses.

In this way, the pulse combustor continues combustion by vibration of the air column, and once ignited, the combustion air is self-suctioned, and there is no need to drive the combustion blower. Therefore, the combustion blower only needs to be operated until ignition occurs.

In addition, if necessary, for example, in the case of a device that requires after-purging, the operation may be performed before ignition and after ignition.

In FIG. 1, 1a is a DC source for an integrated circuit, 1b is a DC power source for a relay, 2 is a combustion control integrated circuit,
An example is ■Hitachi's new Hk-16605W: The integrated circuit 2 operates by inputting the load temperature signal, clock pulse, and flame detection signal (all input terminals are not shown), and when the load temperature decreases, Blower output terminal 2a ((Lo
level, the blower relay is driven to start pre-purge, and after the pre-purge time, the igniter output terminal 2b and the fuel valve output terminal 2c are set to Lo level, and the igniter relay 4,
Drives the combustion valve relay 5. When ignited, either at the same time or after the ignition time has elapsed, the output terminal 2b is set to Hi level and steady operation begins. If there is no ignition within the ignition time, the output terminals 2a, 2b, 2C are set to Hi level and the operation is stopped.

The resistor 9 and the capacitor 101-t constitute a timer, and the capacitor 1o completes energization. The comparator 11 is provided to measure the discharge time of the capacitor. 12, 13, and 14 are transistors, 15 to 22 are resistors, and 23 to 29 are diodes.

The operation of this configuration will be explained with reference to FIG. The black in Figure 2 shows the parts &' (in Figure 1).When the load temperature decreases,
Since the blower output terminal 2a becomes LO level, the transistor 12 turns on, the capacitor 10 is immediately charged, and the output of the comparator 11 becomes Hi level. . After a predetermined time, output terminals 2b and 2C are set to Lo.
When the level is set, relays 4 and 5 are turned on, and ignition begins. When the igniter is ignited, the igniter output terminal 2b becomes Hi level at the same time or after the ignition time ends, and the operation of the igniter is stopped. The output terminal 2c continues to be at Lo level. As a result, transistor 14 is turned on, transistor 13 is turned off, blower relay 3 is turned off, the blower is stopped, and steady combustion begins.

When the temperature of the load rises to a predetermined temperature or higher due to combustion, the integrated circuit 2 sets the output terminals 2a, 2b, and 'lc to the normal level, and attempts to stop the operation of all devices.This causes the transistor 12 to turn off. , the comparator 11 continues at Hi level for a predetermined time until the charge in the capacitor 10 is discharged and the (+) input terminal becomes the (-) input terminal. - Since the power output terminals 2b and 2c are at Hi level, the transistor 18 is OFF'. Therefore, the transistor 13 is turned on again, the pl relay 3 is turned on, and afterbarge is performed.

As described above, afterpurging can be performed using the existing combustion control circuit that does not have afterpurge.

Further, although an electromagnetic relay is used in the above embodiment, the relay 4 may be a gate of a thyristor of a pulse transformer, for example.

As described above, according to the present invention, afterbarge can be performed using a combustion control circuit that does not have afterbarge.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram of a combustion control device according to an embodiment of the present invention, and FIG. 2 is an operation waveform diagram of each component in FIG. 1. la, lb... DC power supply 2... Integrated circuit for combustion control 2a... Output terminal for blower 2b... Output terminal for igniter 2c... Output terminal for combustion valve 3... Relay for blower 4 ... Relay for igniter 5 ... Relay for fuel valve 11 ... Comparator ＼J＼ Mi

Claims (1)

[Claims] When the operation starts, a first signal for driving the blower is output,
A combustion control device comprising a combustion control circuit including a first output terminal that outputs a second signal for stopping the blower when the operation is stopped, and a switching means for the blower operated by a signal from the first output terminal. A first switching element is provided to energize the CR timer in accordance with the signal No. 1, and a second switching element is provided to conduct in accordance with the charge of the CR timer and operate the switching means, so that the CR timer has a predetermined time for discharging. Combustion control device with all the features provided.