JPS5838281Y2 - Automatic combustion switching device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a combustion control device, and in particular, in a combustion device configured to supply fuel (oil) using an electromagnetic pump as a fuel supply means to cause combustion, The present invention relates to an automatic combustion switching device configured to appropriately control the subsequent fuel supply amount to obtain ideal combustion characteristics.

Domestic water heaters that use oil as fuel are designed to be more compact in consideration of installation location and cost, and are also designed to remove draft regulators to reduce noise during combustion, especially when igniting. .

Therefore, in the case of this type of small water heater, the resistance of the chimney is added in addition to the resistance inside the combustion furnace, so the pressure inside the furnace at the time of fuel ignition becomes extremely high. If 100% of the air is supplied for combustion, the pressure inside the furnace will be higher than the static pressure of the fan that supplies air, which may cause oscillating combustion or backfire noise.

One way to solve this problem is, for example, to use a larger fan to blow air into the combustion furnace with a force stronger than the pressure inside the furnace at the time of ignition, but using a large fan will cause ignition noise and fan rotation noise. As the motor becomes larger, noise problems occur, and in addition, the larger the motor output, the higher the price.

As another solution, the oil burner has two fuel injection nozzles, and a timer and an electromagnetic valve are used to first supply, for example, 60% of the fuel from one nozzle at the time of ignition to cause combustion, and then keep it in contact for a certain period of time to the other nozzle. There is a method of burning by opening the nozzle and supplying the remaining 40%.

According to this method, since it is possible to achieve low combustion at the time of ignition and to suppress the pressure inside the furnace, it is possible to completely burn the fuel without causing oscillating combustion or the like, without using a large fan to supply strong air.

Therefore, it is possible to miniaturize the fan and operate water heaters, etc. with low noise, but on the other hand, the structure of the oil burner part, including the timer and solenoid valve, becomes significantly complicated and the overall price is high. This makes it unsuitable for household use.

Therefore, the present invention uses an electromagnetic pump as a fuel supply driving source, and aims to provide an automatic combustion switching device that can solve the above-mentioned problems all at once by making good use of the characteristics of this electromagnetic pump. It is.

That is, general electromagnetic pumps have different efficiencies when operating with DC power and when operating with AC power.

For example, if the amount of fuel supplied when the electromagnetic pump operates with DC power is 100, the amount of fuel supplied decreases to about 80 when it operates with AC power.

In view of the above-mentioned characteristics of the electromagnetic pump, the present invention operates the electromagnetic pump with AC power at the time of combustion ignition, thereby suppressing the amount of fuel supplied to a lower amount than the rated amount and burning, and after ignition, the electromagnetic pump is operated with DC power. It is configured to operate, supply a rated amount of fuel, and burn it, allowing a small combustion device with high internal pressure to be operated with low noise without causing vibration combustion using a small fan, and reducing the cost of the entire device. It is characterized by being devised so that it can be finished at a low cost.

An embodiment of the present invention will be described in more detail below based on the drawings.

FIG. 1 is an electrical wiring diagram of the present invention, in which 1 is an AC power supply;
2 is a switch for starting combustion connected to this AC power source 1;
3 is a first timer connected to the AC power source 1 via the switch 2, and is provided with a normally open time contact 3a.

4 is a second timer connected in parallel to the first timer 3, and has a normally closed time contact 4a, and its operating time is delayed from that of the first timer 3. The timer circuit shown in its entirety is constructed.

5 is a fan motor connected to the AC power supply 1 via the switch 2.

Further, 6 is a rectifier connected to the switch 2 via the normally open time contact 3a of the first timer 3, for example, a diode 6a.
This is half-wave rectification.

7 is an ignition transformer connected in series to the switch 2 via the normally closed time contact 4a of the second timer 4, and 8 is connected to the second timer 4 via the normally open time contact 3a of the first timer 3 and the rectifier 6. This is an electromagnetic pump connected in parallel to a series circuit consisting of a normally closed time contact 4a and an ignition transformer 7, and supplies oil to an oil burner (not shown).

Reference numeral 9 denotes a first relay connected in parallel to the timer circuit TD via the normally closed timer contact 4a of the second timer 4.

10 is a timer circuit T via the normally open contact 9a of the first relay 9, the rectifier 6 and the normally open timer contact 3a of the first timer 3.
A second relay connected in parallel to D, whose normally open contact 10
A is connected in parallel to the rectifier 6 as a bypass contact.

Therefore, the first relay 9 and its contacts 9a, the second relay 1
0 and its contact 10a, time contact 3a of the first timer 3
The time contact 4a of the second timer 4 constitutes a power switching circuit (generally indicated by the symbol PE) to be supplied to the electromagnetic pump 8.

In the automatic combustion switching device configured as described above, when the switch 2 is turned on as shown in FIG. 2A, the first timer 3, the second timer
When the timer 4 is energized, the first relay 9 is energized and its contacts 9a are closed as shown in the second diagram, and the fan motor 5 is rotated as shown in FIGS. 2B and C. Furthermore, the ignition transformer 7 is energized.

When the fan motor 5 rotates and the ignition transformer 7 is energized, raw gas remaining in the furnace is pre-purged.

Next, when the set time t1 of the timer 3 of the hair 1 is reached after the switch 2 is turned on, the first timer 3 is turned on as shown in FIG. 2E.
is activated and its normally open time contact 3a is closed.

When the contact 3a is closed, the second relay 10 is energized as shown in FIG. 2'F, and its normally open contact 10a is closed.

When the contact 10a is closed, full-wave AC power is applied from the AC power supply 1 to the electromagnetic pump 8, and the electromagnetic pump 8 is operated as shown in FIG. 2G.

In this way, the amount of oil supplied by the electromagnetic pump 8 driven by AC power is lower than the required rated amount, for example, 80% of the required rated amount.
It is the rank.

Therefore, the electromagnetic pump 8 supplies oil to an oil burner (not shown) with the flow rate limited to about 80%, and the oil is ejected from the burner and ignited by the ignition transformer 9 to cause low combustion.

After that, when the set time t2 of the timer 4 for hair 2 is reached, the second
As shown in Figure H, the second timer 4 operates to open its normally closed time contact 4a.

When the contact 4a opens, the ignition transformer 7 stops its operation, and the first relay 9 is deenergized and its contact 9a opens.

When the contact 9a opens, the second relay 10 is opened as shown in FIG. 2F.
deenergizes and its contact 10a opens.

When the contact 10a opens, the current from the AC power supply 1 is half-wave rectified by the rectifier 6, and the electromagnetic pump 8 is driven by this rectified power.

At this time, since the electromagnetic pump 8 is driven by DC power, the oil can be supplied to the oil burner at a flow rate of 100% for high combustion.

Generally, the set time limit tl of the first timer 3 is within 20 seconds, and the set time limit t2 of the second timer 4 is 25 seconds or more, so the low combustion time Tt2-11 is about 5 seconds.

As described above, the present invention uses an electromagnetic pump as a fuel supply drive source, and when combustion ignites, the pump is driven with AC power for a predetermined time, and after ignition, the pump is driven with DC power by a rectifier, so that when combustion ignites, the pump is driven with DC power. The amount of fuel supplied can be kept lower than the required rated amount for combustion, and after ignition, the required rated amount of fuel can be supplied for combustion.

Therefore, the present invention has a small combustion chamber and a strong draft regulator, making it possible to reduce the pressure inside the furnace at the time of ignition as low as possible through low combustion, even in combustion equipment such as household water heaters, where the pressure inside the furnace at the time of ignition is very high. This makes it possible to reduce the air supply pressure required for combustion, making it possible to downsize the fan used.Furthermore, there is no need to worry about vibration combustion occurring during ignition, making the combustion equipment less noisy. can be driven with.

In addition, since the present invention is a very simple device that utilizes the characteristics of an electromagnetic pump, the fan used is also small and inexpensive. It is possible to reduce the price and has extremely high practical value.

[Brief explanation of the drawing]

FIG. 1 is an electrical wiring diagram showing an embodiment of the present invention, and FIG. 2 is an operational flow chart thereof. 1...AC power supply, 2...Switch for starting combustion, 3...First timer, 3a...
...Normally open time contact of the first timer, 4...
Second timer, 4a... Normally closed time contact of second timer, 6... Rectifier, 6a...
Diode, 7...Ignition transformer, 8...
...Electromagnetic pump, 9...First relay, 9a.
...Normally open contact of the first relay, 10...
Second relay, 10a... Bypass contact which is a normally open contact of the second relay, TD... Time limit circuit, PE... Power switching circuit.

Claims (1)

[Scope of utility model registration request] A timer circuit is constructed by connecting a first timer and a second timer whose operation time is set later than that of the first timer to an AC power source via a switch for starting combustion. A rectifier is connected through the normally open time contact of the first timer, and an ignition transformer is connected in series to the switch via the normally closed time contact of the second timer, An electromagnetic pump that serves as a drive source for supplying burning material to the combustion furnace is connected in parallel to a series circuit consisting of the normally closed time contact of the second timer and the transformer via the normally open time contact of the first timer and a rectifier. A first relay is connected in parallel to the time circuit through the normally closed time contact of the second timer, and the time circuit further includes a normally open contact of the first relay and the rectifier. and a second relay is connected in parallel through the normally open time contact of the first timer, and the normally open contact of the second relay is connected in parallel to the rectifier as a bypass contact. Combustion switching device.