JPH0599427A - Combustion air adjusting device - Google Patents

Abstract

PURPOSE:To provide a combustion air adjusting device in which the total amount of secondary combustion air is always kept constant and a stable combustion is carried out in whatever position a damper may occupy and whatever variation in distribution ratio of secondary combustion air flowing in each of flow dividing ports in a duct may occur. CONSTITUTION:A duct 18 divides a secondary combustion air passage into two directions. A flat opening adjusting damper 19 having two holes or the first passage 15a and the second passage 15b corresponding to a passage resistance in the secondary air passage and a shaft 21 are arranged within the duct 18. A stepping motor 22 drives the shaft 21 and a control part 23 controls a driving of the stepping motor 22 according to the output from a burner thermistor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion air control device for a petroleum hot air heater or the like.

[0002]

2. Description of the Related Art Generally, a highly accurate combustion air control device is required for stable combustion using oil or gas as fuel. The conventional combustion air control device will be described below.
In FIG. 3, reference numeral 1 is a duct that branches a secondary air passage for combustion in two directions, 2 is a damper provided in the duct 1, 3 is a stepping motor that rotates the damper, and 4 is a control unit that controls the stepping motor. is there.

The operation of the combustion air conditioning apparatus constructed as above will be described. First, the control unit 4 controls the stepping motor 3 to rotate according to a predetermined program. When the stepping motor 3 rotates, the damper 2 also rotates, thereby branching the secondary combustion air in two directions and changing the distribution ratio.

[0004]

However, in the above-mentioned conventional configuration, when the stepping motor 3 rotates, the position of the damper 2 changes, and the distribution ratio of the secondary air for combustion flowing through each branch port of the duct 1 changes, Since the opening degree and the resistance change depending on the rotation angle of the damper, the total amount of secondary air changes, which causes a problem that combustion becomes unstable.

The present invention has been made to solve the above problems, and has as its object to realize stable combustion by accurately adjusting the air amount.

[0006]

In order to achieve the above object, the present invention has a duct in which a secondary air passage for combustion to a burner is branched in a plurality of directions, and a plurality of holes in a plane provided in the duct. A damper, a shaft for rotating the damper, a stepping motor for rotating the shaft,
A control unit for controlling the stepping motor is provided, and the passage of the hole of the damper is provided with a combustion air adjusting device provided corresponding to each branch port of the duct.

[0007]

With the above-described structure, the present invention ensures stable combustion because the total amount of secondary air for combustion is always constant regardless of the position of the damper and the distribution ratio of the secondary air for combustion flowing through the flow dividing ports of the duct. Will be realized.

[0008]

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

In FIGS. 1 and 2, 11 is a vaporizing tube, and 12
Reference numeral 13 is a burner portion, 13 is a burner case arranged so as to block the combustion portion A and the atmosphere B and cover the vaporization cylinder 11, and an air passage 15 for secondary air for combustion is formed with the secondary air guide 14. .. The air passage 15 is branched into a first passage 15a directly connected to the combustion portion A and a second passage 15b directly connected to the combustion portion A via the outer circumference of the vaporization cylinder 11. Reference numeral 16 is a burner thermistor for detecting the vaporization cylinder temperature, and 17 is a heater for increasing the vaporization cylinder temperature. Reference numeral 18 is a duct that branches the air passage 15 into first and second passages, and a damper 19 for opening adjustment having two holes according to passage resistance of the air passages 15a and 15b and a damper for preventing air leakage. A spring 20 for pressing 19 onto the surface of the duct 18
A shaft 21 for driving the damper 19 is provided in the duct 18. A stepping motor 22 drives the shaft 21. A controller 23 controls the driving of the stepping motor 22 based on the output from the burner thermistor 16.

The operation of the combustion apparatus constructed as above will be described below. In accordance with the temperature of the vaporization cylinder 11 detected by the burner thermistor 16, the stepping motor 22 is rotated via the control unit 23 and the damper 19 is moved, so that the combustion 2 flowing in the first passage 15a and the second passage 15b is moved. Change the distribution ratio of the secondary air. That is, the damper 19 directly connects the combustion section A via the outer periphery of the vaporization cylinder 11.
The vaporization cylinder temperature is maintained at an appropriate temperature by adjusting the flow rate of the secondary combustion air flowing through the first passage 15a connected to the. And
When the combustion amount, environmental conditions, etc. change, and the vaporization cylinder temperature changes accordingly, the stepping motor 22 rotates and the damper 19 moves, but the secondary air passage hole for combustion of the damper is passed through the passage of each branch port of the duct. Since the two holes are provided in correspondence with the resistance, the total amount of the secondary air for combustion is always constant regardless of the position of the damper and the change of the distribution ratio of the secondary air for combustion flowing through each branch port of the duct 18. Therefore, stable combustion can be realized.

[0011]

As described above, according to the present invention, the configuration in which the plurality of holes are provided corresponding to the respective diversion ports of the duct allows the position of the damper to be changed and the secondary air for combustion flowing through the diversion ports of the duct to flow. No matter how the distribution ratio changes, stable combustion can be realized because the total amount of secondary air for combustion is always constant.

[Brief description of drawings]

FIG. 1A is a diagram of a damper according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view of a main portion of the damper movable portion.

FIG. 2 is a diagram of a combustion device according to an embodiment of the present invention.

FIG. 3 Conventional diagram

[Explanation of symbols]

 18 duct 19 damper 21 shaft 22 stepping motor 23 controller 15a first passage 15b second passage

Claims (1)

[Claims] 1. A duct in which a secondary air passage for combustion to a burner is branched in a plurality of directions, a damper having a plurality of holes in a plane provided in the duct, a shaft for rotating the damper, and the shaft. A combustion air control device comprising a stepping motor for rotating and a control unit for controlling the stepping motor, wherein the passage of the hole of the damper is provided so as to correspond to each branch port of the duct.