JPS588909A - Apparatus for controlling combustion by gun type burner - Google Patents

Abstract

PURPOSE:To vary the amount of supply of oil so as to control the amount of the combustion, by providing a plurality of pumps in an oil transportation passage, and changing the operating efficiency of the pumps. CONSTITUTION:In the way of the oil transportation passage 2, the first pump 4 and the second pump 5 that are driven electromagnetically and have the same capacity are connected in series through a connecting pipe 10. As the two pumps are connected in series, the discharge pressure of the second pump becomes high, and even in the case the flow rate is minimum, as the fuel spouted from a nozzle 3 becomes good fine particles and uniform atomized state, a favorable combustion state can be obtained. Thus, the formation of soot can be reduced, and the amount of combustion can be ideally controlled. A temperature sensing section 9 such as a thermistor is provided in the furnace where the nozzle 3 is directed, and is connected to a control means 11 such as a phase control apparatus so that the first pump 4 and the second pump 5 are controlled.

Description

[Detailed description of the invention] This invention relates to a control device for a gun type burner.

In particular, the present invention relates to a combustion amount control device for a gun-type burner that increases the oil pressure sent to the pump and expands the flow rate change range within the effective combustion pressure.

Gun-type burners have the advantage of good ignition/extinguishing response and generate little soot, but have the disadvantage that the amount of combustion cannot be controlled. Therefore, conventionally, two nozzles are provided and the combustion amount is controlled by, for example, stopping fuel injection from one nozzle. However, according to this device, only stepwise control corresponding to the number of nozzles can be performed, and two nozzles must be provided with a predetermined distance between them.

When only one nozzle was operated, there was a problem in that the flame was unevenly distributed.

Ninth, the so-called return nozzle method has been developed and is used in combustion devices such as dryers.

This method uses a bypass nozzle and a return pipe with a needle valve installed as a bypass, allowing part of the oil pumped by the pump to be returned to the oil tank, allowing continuous flow control. That is. However, this method has the disadvantage that manual adjustment of the needle valve is inaccurate and cumbersome.

Also, we decide to control this needle valve automatically.

The disadvantages are that the structure is complicated and expensive.

Therefore, an object of the present invention is to realize a combustion amount control device for a gun-type burner with a simple configuration that continuously changes the amount of oil fed to the gun-type burner to control the combustion amount.

The present invention will be described in detail below based on the drawings.

In order to facilitate understanding of the present invention, characteristics of the gun type burner will be explained using the graph of FIG. 1.

The characteristics of the burner required as a heat source for a grain dryer are:
At least the amount of combustion can be controlled.

It is necessary to control the fuel flow rate at a flow rate ratio of about 1:2. To achieve such a flow rate ratio.

Since the relationship between the flow rate Q and the discharge pressure P is approximately PoCQ2, the oil feeding pressure, which is the discharge pressure, needs to be changed at a ratio of 1:4. However, the maximum pressure of a normal electromagnetic pump is 1
It is about 3:00 to 14:00/-. Therefore, this maximum pressure 1
If the maximum flow rate at 41 k/cd C) is 6 t/H, the pressure at the minimum flow rate of 3 t/H, which is the VgO flow rate, is approximately 1/4, 3 Kt/-, as shown in Figure 1. Put it away. However, in gun-type burners, if the pressure is too low, the particle size of the sprayed fuel will be large and uneven, and the combustion condition will be very poor.
A pressure of /- is required. Therefore, the minimum pressure is 7K.
If t/- is 9, if you calculate backwards, you will need a maximum oil delivery pressure of 28-/-, which is four times that amount. -) t', in which case the effective combustion pressure is approximately 7 to 28 kg/li. However, as mentioned above, general commercially available electromagnetic pumps have a maximum discharge pressure of 14
Producing an electromagnetic pump having a discharge pressure of about Kg/- has not been realized, as it is technically difficult and has the disadvantage of significantly increasing the production cost.

An embodiment of the present invention that improves the above-mentioned drawbacks will be explained with reference to FIG.

Reference numeral 1 denotes an oil tank, and an oil feed passage 2 communicates with this oil tank, and this oil feed passage 2 opens and ends at a nozzle 3. A first pump 4 and a second pump 5 having the same capacity and driven by electromagnetic force are connected in series along the communication pipe IQK in the middle of the oil supply passage 2.

In addition, 6 is an ignition tone, 7 is an igniter, and 8 is a blower. Further, a temperature sensing section 9 such as a thermistor is provided in the furnace toward which the nozzle 3 is directed, and this temperature sensing section 9 is provided.
9 is connected to a control means 11&c such as a phase angle control device, and the control means 11 directly controls the operation of the first pump 4 and the second pump 5.

Note that in this embodiment, the control means 11 is used.

Control the phase angle θ appropriately from DO to 90° using a thyristor, etc. Kyoυ2 Change the energization time to adjust the flow rate to 1;z
Although the pump operation rate is controlled continuously within the range of , the operating rate of the pump can also be changed by pulse number control, pulse width control method, or other methods.

However, if the pumps are connected in series in two stages as described above,
As shown in FIG. 3, the graph of the second pump discharge pressure P2 with respect to the first pump discharge pressure PIK is drawn as P2=2P1.9 For example, if nine pumps are used that exert a maximum pressure of 144/ad.

P2 indicates the maximum discharge pressure of 28 to/-.

Therefore, as shown in Figure 4, the maximum pressure is 284/al1
If K is set to obtain a flow rate of 6 A/H at a time, 1/2 of that
When a flow rate of 98t/h is to be pumped, the calculated value is 7! according to the embodiment of the invention of B. /-yo) is also slightly lower at 6.2K.
This can be done at t/-. Therefore, even in the case of this minimum flow rate, the fuel injected from the nozzle 3 is in a fine and uniform atomized state, so that a preferable combustion state can be achieved.

In addition, when the pressure is high, the spray particles are generally too fine and the ignition performance deteriorates.

According to the experimental results of this invention, the rise in pressure of the electromagnetic pump is not sudden, and ignition is completed by the time the maximum pressure zsKp/- is reached, so there is no problem.

If there is still pressure buildup 1)K inconvenience.

If the phase angle 0 of the phase angle control means is temporarily shifted and increased only during ignition, the ideal ignition pressure will be 5 to 10.
&I/ai K can be easily adjusted.

In the above embodiment, two pumps are used to double the pressure, but it goes without saying that a multi-stage series system with three or more pumps can be used.

As is clear from the above description, according to the present invention, it is possible to ensure good response between ignition and extinguishment of the gun type burner, and to reduce soot, which is important when using the gun type burner as a direct flame type heat source for grain drying. It is possible to take advantage of the fact that the amount of combustion is small and to ideally control the amount of combustion. Compared to the conventional return nozzle method, etc., the structure is extremely simple, the manufacturing cost is low, and maintenance and inspection are easy.

[Brief explanation of the drawing]

Figure 1 is a graph showing the flow rate characteristics of a commercially available electromagnetic pump.
FIG. 2 is a schematic system diagram showing an embodiment of the present invention, FIG. 3 is a graph showing the discharge pressure of the first pump and the second pump,
FIG. 4 is a graph showing the relationship between the flow rate Q and the discharge pressure P of the device according to the present invention. In the figure, 2 is an oil feeding passage, 3 is a nozzle, 4 is a first pump, and 5 is a second pump. Agent Patent Attorney Yoshimi Nishigo Figure 3: Apply slight pressure to the pump 1 in Figure 4, R(k), /c inertia 1) Figure 4, GL()/M)

Claims (1)

[Claims] Increasing the oil supply pressure to the gun-type burner and expanding the range of flow rate changes within the effective combustion pressure. 1. A combustion amount control device for a gun-type burner, comprising a control means for changing the operating rate of the pump by changing the amount of electricity.