JPH10246435A - Hot air heating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the noise of a blower by providing a controller for periodically increasing the amount of blast at a specific interval after a flame current decreases by a specific value and stopping combustion when the flame current being detected through a flame rod is equal to or less than a specific oxygen shortage detection level. SOLUTION: A flame rod 6 is provided in a flame 12, and the flame rod 6 detects a flame current when an AC voltage is applied to an area to a flame hole 2b, thus detecting a combustion state. Also, a controller 13 switches the speed of a blower 5 to for example, 700-900rpm after the frame current decreases by several pA from a value when it is normal on a slight combustion and applies an interval for increasing the amount of blast. When it is normal where no oxygen shortage advances, no interval for increasing the amount of blast is applied so that the noise of the blower 5 becomes slight. However, when the indoor oxygen shortage advances, an interval for increasing the amount of slight wind is applied, thus warning oxygen shortage and hence improving safety.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a warm air heater for stopping combustion when oxygen is insufficient.

[0002]

2. Description of the Related Art When a flame rod is provided in a flame of a burner and an AC voltage is applied between the flame rod and a ground electrode (flame hole), a flame current is detected by a rectifying action of the flame, and a combustion state is determined. There is an example of a hot air heater to be detected (for example, Japanese Patent Publication No. 3-3709).

[0003]

The flame current is calculated as shown in FIG.
As shown in (2), the value becomes lower as the combustion amount becomes lower. However, at the time of oxygen-deficient combustion, as shown in FIG. 4, in the case of micro-combustion with a low combustion amount, the effect of a decrease in oxygen concentration is unlikely to appear. Not detected. As described above, since the difference between the normal frame current value and the frame current value at the time of oxygen deficiency detection is small, variations in the frame current value due to variations in the fuselage, or a decrease in the frame current value due to the life of the fuselage, etc. The oxygen concentration at the oxygen deficiency detection level was 16% or less, and there was a problem that the specified oxygen concentration (16% or more) could not be satisfied. In addition, when the above interval is applied from the beginning, the number of rotations is switched (for example, 700 rpm → 900 rpm), and there is a problem that the noise of the blower is a concern.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a frame rod for detecting a flame current is inserted into a flame of a burner, and a flame rod is inserted between the flame rod and the burner. When the flame current detected by the flame rod is reduced by a predetermined value at the time of slight combustion, the air flow rate is periodically increased at predetermined intervals, and the flame current detected through the flame rod is changed to a predetermined oxygen. When the level is below the deficiency detection level, the combustion is stopped.

[0005]

During the slight combustion, the air flow is periodically increased at predetermined intervals after the flame current detected by the flame rod has decreased by a predetermined value. Since the interval is not taken, the noise of the blower does not matter.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the drawings, reference numeral 1 denotes a main body comprising a hot air heater,
Reference numeral 2 denotes a burner. The burner 2 has a primary air hole 2a at one end and a flame hole 2b at an upper portion. The burner 2 is provided inside the main body 1 to burn a liquid fuel such as petroleum. Reference numeral 3 denotes a vaporizer having a nozzle 3a, which is provided opposite to the burner 2. Reference numeral 4 denotes an inner duct, which is provided behind the burner 2 to form a combustion chamber. Reference numeral 5 denotes a blower having a variable blowing amount, which is provided inside the main body 1 for blowing to the burner 2. Reference numeral 6 denotes a frame rod, which is provided opposite to the flame hole 2b of the burner 2 to detect a flame current flowing through the flame 12 of the flame hole 2b. Reference numeral 7 denotes a support plate, and a secondary air hole 7a is provided on the front side of the main body 1.
The inner filter 8 is provided on the back side of the main body 1 and supports the burner 2. A hot air outlet 9 is provided on the front surface of the main body 1. Reference numeral 10 denotes an air duct, and an inner duct 4
Also, it is attached to the main body 1 in order to partition the air from above the blower 5 to the upper part of the hot air outlet 9. Reference numeral 11 denotes a variable oil amount electromagnetic pump connected to the vaporizer 3. Reference numeral 13 denotes a controller for controlling the hot air heater, and the controller 13 includes a microcomputer having a timer function.
When the flame current detected by the flame rod 6 becomes a flame current at the oxygen deficiency detection level, the burner 2 is connected to the vaporizer 3, the blower 5, the flame rod 6, and the electromagnetic pump 11 to extinguish the fire.

Next, the operation of this embodiment will be described.

When the power is supplied to the warm air heater, the vaporizer 3 is energized. When the vaporizer 3 reaches the vaporization temperature, the electromagnetic pump 11 is energized, and the oil supplied from the electromagnetic pump 11 is supplied to the vaporizer 3. The vaporized gas is ejected from the nozzle 3a to the burner 2. At this time, the primary air and the vaporized gas flowing from the primary air holes 2a are premixed, and are ejected from the flame holes 2b of the burner 2, thereby forming a flame 12. A flame path 6 is provided in the flame 12. When an AC voltage is applied between the frame rod 6 and the ground electrode (flame hole 2b), the flame rod rectifies and the flame rod 6
Is to detect the combustion current by detecting the flame current.

[0009] The controller 13 of the present invention provides
After a several μA drop from the normal frame current, the rotation speed of the blower 5 is switched to, for example, 700 rpm → 900 rpm, and an interval for increasing the blowing amount is applied. Since no increase interval is required, the noise of the blower 5 does not matter. In addition, since the interval of the increase in the amount of air blows when the indoor oxygen deficiency has advanced, it becomes a notice of oxygen deficiency,
Further, safety can be improved.

[0010]

As described above, according to the present invention, the blower volume is periodically increased at a predetermined interval after the frame current becomes lower than the normal frame current by a predetermined value. In addition, an interval for increasing the amount of blown air takes place at a time when the oxygen deficiency in the room has advanced, and at that time, a notice of the oxygen deficiency is given. That is, there is an effect that a safe and convenient hot air heater can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a warm air heater showing one embodiment of the present invention.

FIG. 2 is a detection characteristic diagram of an air-fuel ratio and a frame current of a hot air heater according to an embodiment of the present invention.

FIG. 3 is an oxygen deficiency detection characteristic diagram of the hot air heater according to one embodiment of the present invention.

FIG. 4 is an oxygen deficiency characteristic diagram of a warm air heater showing a conventional example.

[Explanation of symbols]

 2 Burner 3 Vaporizer 5 Blower 6 Frame rod 11 Electromagnetic pump 13 Controller

Claims (1)

[Claims] 1. A blower (5) for blowing a variable amount of air,
An electromagnetic pump (11) for variably feeding the oil amount, a vaporizer (3) connected to the electromagnetic pump (11), a burner (2) opposed to the vaporizer (3), and a burner (2). ), A frame rod (6) inserted into the flame to detect a frame current, and the frame rod (6) and the burner (2).
When the flame current detected by the flame rod (6) during the slight combustion is lowered by a predetermined value and the air flow rate is periodically increased at predetermined intervals after the flame current is reduced, the flame rod (6) And a controller (13) for stopping combustion when the flame current detected by the method (1) is equal to or lower than a predetermined oxygen deficiency detection level.