JPS6044724A - Safety combustion device - Google Patents

Abstract

PURPOSE:To reliably detect an abnormal combustion before a CO and a soot are produced, by comparing a flame current from two flame rods having different heights and provided inside a combustion chamber. CONSTITUTION:A primary air control damper 1 is provided adjacent to the suction port of burner 2, and a nozzle 3 is provided for injecting a fuel from the opening of damper 1 into the burner 2. A casing is provided to surround the primary flame port 9 of burner 2, having an opening 11 defined therethrough. The opening 11 serves as a secondary flame port. While a first flame rod 12 is provided inside the casing, a second flame rod 13 is provided above the opening 11. A comparing circuit section 14 is provided for comparing flame currents from these two flame rods, and a driving circuit 15 is provided for receiving a signal from the comparing circuit section and driving a solenoid valve. If the primary air control damper 1 is clogged or adversely affected, a flame propagates inside a primary combustion chamber or the casing 10, and its top end reaches the second flame rod 13. Any abnormal combustion is thus detected, by comparing amplitudes of electric currents from these two flames.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a combustion safety device, and in particular uses two flame rods to prevent abnormal combustion due to clogging of the damper portion of a burner.
The purpose is to reliably detect abnormal combustion due to lack of oxygen before carbon monoxide is generated.

Page 2 Configuration of conventional example and its problems The conventional type of combustion safety device is as shown in Figure 1.
A burner 2 having a damper 1 for secondary air control, a nozzle 3 for injecting fuel, and a solenoid valve 4 for controlling the supply of this fuel.
, a comparison circuit section 7 for comparing the flame signals obtained from the flame rod 5 provided in the flame, the flame rod 6 provided in the area where there is no flame, and the flame signals obtained from both of the flame rods, and the output signal from this circuit. It consisted of an AND circuit section 8 which receives the input temperature and drives the solenoid valve. In this configuration, for example, when the oxygen concentration decreases and a so-called oxygen-deficient state occurs, the flame floats and evaporates as shown in FIG. The changes in the flame current until such an oxygen-deficient state is reached are as shown in FIG. 3, and at a point t1 when the current value If5 of the flame rod 5 becomes less than a certain value, an L level is output from the comparator circuit section 7. The electromagnetic valve was closed by the electromagnetic valve driving AND circuit 8 which received this signal.

On the other hand, if the primary air control damper 1 is clogged with dust or the like, the flame will elongate as shown in FIG.
Since the liquid starts to flow as shown at point P in the figure, L level is output from the comparator circuit section 7, and the solenoid valve 4 is closed.

In the conventional configuration, the lift state of the flame was detected by the flame rod 5 when there was a lack of oxygen, but in reality, when the flame lifts and there is a lack of oxygen, carbon monoxide (hereinafter referred to as C) is already detected. (referred to as ○) was generated in large quantities, and it was extremely dangerous if this device was used in indoor combustion appliances.

If the primary air control damper 1 is clogged, the solenoid valve is closed by detecting the flame current If6 obtained by the flame rod 6, as shown in FIG. The change in flame current with respect to the degree of damper occlusion in this case is shown in FIG. 5, and the solenoid valve is actually closed at point P. However, when the combustion tower is throttled, the flame expands because the combustion is promoted by the surrounding secondary air.The flame current is obtained in the flame rod 6 only when the air is controlled by the air control shaft 1. 41il< 11 is clogged at the end, and the flame is elongated. In this case, 1-chip is generated, soot is discharged, and at the same time, CO is also generated. Therefore, it is still an indoor combustor! ↓ Because it is dangerous when used in a burner, there was a problem that the burner could hardly reduce the combustion Qlk (ij).

The purpose of the present invention is to solve the problems of the prior art, and is to provide one frame rod in a housing that surrounds a secondary flame hole and has a secondary flame hole, and another frame above the flame hole. The purpose of this is to reliably detect abnormal combustion before CO or IT is generated by comparing the flame currents flowing from both flame rods.

In order to achieve this objective 1-1, the present invention includes a solenoid valve for controlling the supply of fuel, a burner, a burner surrounding the primary flame hole and a secondary flame hole. 71) - From Herrond - 1 A frame having a frame rod, one frame rod provided in this frame, and another frame provided on one side of the frame rod, flame from these frame rods. It consists of a comparison circuit section that compares signals, and a drive circuit section that inputs the signals output from this circuit and drives the solenoid valve. With this structure, when the flame is clogged or when there is a lack of oxygen, the flame tends to spread inside the casing, which becomes an empty combustion chamber, because there is no supply of secondary air from the surroundings. Therefore, abnormal combustion is detected by comparing the flame current values from two flame rods installed at different heights in the comparison circuit, and a signal is output from this circuit to the drive circuit to close the solenoid valve. The burning will be stopped.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 6 to 10. In the figures, the same parts as in FIGS. 1 to 5 are given the same numbers.

In the figure, an air control damper 1 is provided near the suction port of the burner 2, and there is a nozzle 3 for injecting fuel into the burner 2 from the opening of the damper 1. The jetting of fuel from this nozzle is controlled by a solenoid valve 4. A W body 10 is provided so as to surround the primary flame holes 61 and 9 of the shunted burner 2, and the housing 10 is provided with an opening 11 through which the secondary flame holes reach.

- In addition, a first frame rod 12 (Uj) is provided in the housing, and a second frame rod 13 (d) is provided on one side of the opening 11-1.
A comparison circuit section 14 for comparing frame currents from both frame rods, and a drive circuit 15 for driving an electromagnetic valve into which the voltage output from this circuit section is input are provided.

In the above configuration, is there a flame during normal combustion without separation? :jr
As shown in the Je diagram, it is formed near the primary flame.

Therefore, more frame current can be obtained from the first frame rod 12, so that the comparator circuit section 14 outputs an H level signal]! is being sent to the dynamic circuit section 15, and the solenoid valve is open. From this state, when an oxygen-deficient state occurs, the flame expands within the casing 10, which is the primary combustion chamber, and reaches the second frame rod 13 as shown in FIG. In this case, if we look at the flame currents obtained from both flame rods until an oxygen-deficient state is reached, we can see that the flame current value If2 from the second flame rod 13 is the same as the current from the first flame rod 12 as shown in FIG. When the value If1 passes the point t1, it begins to rotate by -1. Therefore, in reality, at point t, comparison circuit section 1
4 to the L-level signal is output to the 11th moving circuit section 15, the solenoid valve 4 is closed, and combustion is also stopped.

On the other hand, if the damper 1 for air control 11 is clogged, as shown in FIG. Ru. Changes in the current values of both frames U when the damper is gradually closed are as shown in FIG. 10, and If2 turns Ifl by 1 at damper closure degree M. Therefore, knowing this point, the comparison circuit section 14 outputs an L level signal to the ICJ circuit section 15 to close the solenoid valve 4.

-1] As mentioned above, even in the case of oxygen deficiency, clogged shoes, and abnormal combustion, the flame is blocked by the secondary air supply by the casing 1o, so even a slight oxygen deficiency can easily cause the flame to evaporate. Stretch. For this reason, the change in the flame current from both frame ronds is large, and in this embodiment, there will always be a point where the difference between the two market values becomes zero, so it is necessary to grasp this point and close the solenoid valve 4 reliably. I can do it. When there is a lack of oxygen, the flame lifts up to 1ft from the primary flame hole, allowing CO to be generated quickly and safely, making it safe even when used in indoor combustion equipment. On the other hand, even if the combustion amount is reduced, the flame will easily extend in a circular pattern, and light combustion can be detected by comparing the current values of both flames, so there is no problem even if the burner combustion (7) is reduced. It disappears.

It is more effective than January! According to No. 11 combustion safety device, the following effects are impressive.

(1) The flame hole of the burner is surrounded by a casing with a secondary flame hole, which obstructs the supply of secondary air, so the flame inside the casing is protected against slight oxygen deficiency. Easily expands. Therefore, the flame current obtained from the two flame rods installed at different heights sometimes has a large change in the abnormal combustion i+', so by inputting this flame current to the comparator circuit, the flame is Lift from CO
Abnormal combustion conditions can be reliably detected before they occur.

(2) Even when the combustion is narrowed down, the flame will easily expand even if there is a slight lack of oxygen or a clogged damper, so change the height before CO is generated due to flame lifting or yellow chips. Abnormal combustion conditions can be detected using the two flame rods provided. Therefore, the throttle ratio of the combustor of the burner can be expanded.

[Brief explanation of the drawing]

Figure 1 is a partial cross-sectional configuration diagram of a conventional combustion safety device, Figure 2 is an explanatory diagram of the above combustion safety device in which the flame is in a lifting state due to lack of oxygen, and Figure 3 is a diagram showing the flame in a lifting state as shown in Figure 2. Figure 4 is an explanatory diagram of a state in which the flame is elongated due to damper clogging in the combustion safety device described in 11-2.
As shown in the figure, a characteristic diagram showing the change in flame current at the edge where the flame extends, Figure 6 is a partial cross-sectional configuration diagram of the combustion safety device of the present invention, and Figure 7 is a diagram showing the changes in the flame current at the edge where the flame extends. An explanatory diagram of the flame elongating due to oxygen deficiency in the device, Figure 8 is a characteristic diagram showing the change in ionic current when the flame is extended due to oxygen deficiency as shown in Figure 7 on page 110, and Figure 9 is a characteristic diagram showing the change in ionic current as shown in Figure 6 Fig. 10 is a characteristic diagram showing the change in flame current value when the degree of blockage of the damper is changed, especially in Fig. 9. be. 2... Burner, 4... Solenoid valve, 9...
...-Flame hole, 10... Housing, 11...
... Secondary flame hole, 12.13 ... Flame rod, 14 ... Comparison circuit section, 15 ... Drive circuit section. Names of the 11 members: Patent attorney Toshio Nakao and 1 other person
Figure 1 Figure 4 Figure 2 Fuel Figure 3 Time opening Figure 5 P Datsuba Shuseian Figure 6 Figure 7 Figure 1f Analysis Figure 8 Figure Hour opening Figure 9 1 Lead material No. 10 Kumba blocker

Claims (1)

[Claims] a solenoid valve for controlling fuel supply; a burner; a casing surrounding a primary flame hole of the burner and having a secondary flame hole; a frame rod provided in the casing; A flame rod provided in the housing or above the secondary flame hole, and a comparison circuit section for comparing flame signals outputted from both of the flame rods, and an output signal of the comparison circuit section. A combustion safety device comprising a drive circuit that receives input and drives the solenoid valve.