JPH02298758A - Detecting device of fault of exhaust channel - Google Patents

Abstract

PURPOSE:To enable detection of disconnection of an exhaust tube and the presence of a hole in an exhaust channel without any possibility of electrolytic corrosion by a construction wherein a fault of the exhaust channel is detected by comparing a detection output of a temperature detecting means fitted to the exhaust tube, with a set temperature characteristic condition. CONSTITUTION:A combustion chamber is warmed by combustion of a gas after ignition and a temperature is raised to a proper one. Then, a control circuit 11 drives a convection fan 8 and an electromagnetic relay 10, while electrifying a thermostat 5. At this time point, an exhaust gas reaches an exhaust introduction port. The thermostat 5 fitted to an exhaust tube is warmed to an operation temperature unless there is not such abnormality in an exhaust channel as disconnection of a feed-exhaust air tube from an exhaust pipe, separation of an exhaust cap or the presence of a hole in the feed-exhaust air tube or the exhaust pipe. Accordingly, terminals 11a and 11b of the control circuit 11 are connected and an electric current is supplied to the control circuit 11. The electromagnetic relay 10 driven by the control circuit 11 switches a contact 10a onto the open side. According to this constitution, the control circuit 11 is put in a state wherein it can detect any abnormality in the exhaust channel, in accordance with ON-OFF of the thermostat 5.

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention is a method for detecting defects in the exhaust pipe connected to a forced air supply/exhaust hot air heater, such as disconnection of the exhaust pipe, holes in the exhaust pipe, etc. This invention relates to a detection device.

<Prior art and problems to be solved by the invention> Conventionally, hot air heating employs a forced supply/exhaust method in which combustion air is forcibly supplied from outside through a supply cylinder, and exhaust gas is discharged outdoors through an exhaust pipe. machine (hereinafter simply referred to as hot air heater)
Various types are known.

This hot air heater can have a very high thermal efficiency of about 93%, and also can have a high heating effect because the indoor temperature distribution is uniform.

The hot air heater described above has an air supply fan, a burner, etc. placed in a duct facing the combustion chamber, and a heat exchanger placed above the combustion chamber, and a convection system that blows indoor air onto the heat exchanger. A main body having a fan and connected to the duct,
It consists of an air supply hose that sends air into the main body from the outside in response to the drive of an air supply fan, and an exhaust pipe that sends exhaust gas outside after heat exchange within the main body.

The above-mentioned exhaust pipe includes one that has one exhaust gas inlet at the connection part with the main body, and one that has two exhaust gas inlets. The reason why two exhaust gas inlets are provided is that one of the exhaust gas inlets can be selected depending on the mounting position of the heater body and easily connected to the heater body. The exhaust gas inlet on the side that is not used is closed with a cap, and this cap is welded to the inlet so as not to come off.

By the way, since the exhaust pipe is detachably connected to the main body of the hot-air heater, safety measures must be taken to prevent combustion gas from leaking into the room due to disconnection.

FIG. 6 is a diagram showing a conventional exhaust stack disconnection detection device.

This exhaust stack disconnection detection device is installed in the hot air heater main body (5
0) and the conductive exhaust pipe (51), and connect the power supply circuit (
The voltage generated by 52) is applied between the warm air heater body 50) and the exhaust stack (51), and the current detection circuit (
53), a connection failure of the exhaust pipe (51) is detected by detecting the presence or absence of current.

However, since the above device conducts electricity between the hot air heater main body (50) and the exhaust pipe (51), there is a possibility that the exhaust pipe (51) may become electrolytically eroded and holes may form after long-term use. There's a problem.

Further, although the above device can detect disconnection from the exhaust pipe (51), there is a problem in that it cannot detect holes in the exhaust pipe (51).

Furthermore, if the exhaust stack has two exhaust gas inlets, the exhaust cap is welded to the other exhaust gas inlet, which requires extra labor such as transporting a welding machine and welding work. There is a problem with doing so.

The present invention has been made in view of the above-mentioned problems, and makes it possible to detect disconnection of exhaust pipes and holes in exhaust passages without causing electrolytic corrosion, and also enables welding of exhaust caps. It is an object of the present invention to provide a defect detection device for an exhaust path that can eliminate the need for.

Means for Solving the Problems and Effects> In order to achieve the above objects, the exhaust path defect detection device of the present invention includes a temperature detection means that is attached to the exhaust stack and detects the temperature of exhaust gas, and a temperature detection means for detecting the temperature of the exhaust gas. The exhaust path defect detection means compares the detection output of the detection means with preset temperature characteristic conditions to detect a defect in the exhaust path.

According to the exhaust path defect detection device having the above configuration, if the exhaust pipe becomes defective due to detachment from the hot air heater body or a hole in the exhaust path, exhaust gas leaks. Since the temperature at the location where the temperature sensing means is attached is lower than in normal times or the rate of increase in temperature is slower, the detection output from the temperature sensing means is different from that in normal times. and,
The exhaust path defect detection means compares the detection output output from the temperature detection means with preset temperature characteristic conditions,
If the detection output and the temperature characteristic conditions are different, it is assumed that the exhaust path is defective.

Therefore, it is possible to detect the dislodgement of the exhaust pipe and the perforation of the exhaust vibrator without energizing the exhaust path.

Further, the exhaust pipe has a plurality of exhaust gas introduction ports, and a cap is inserted into the exhaust gas introduction port that is not connected to the hot air heater main body among the plurality of exhaust gas introduction ports, and the cap is inserted into the exhaust gas introduction port that is not connected to the hot air heater main body. If the detection means is attached, it is possible to detect the dislodgement of the exhaust pipe and the perforation of the exhaust passage in the same way as the invention of claim 1, and furthermore, it is possible to detect the dislodgement of the cap. Therefore, there is no need to weld the cap.

Therefore, it is possible to detect the dislodgement of the exhaust pipe and the perforation of the exhaust vibrator without energizing the exhaust path.

<Example> Next, an example of the present invention will be described below with reference to the drawings.

FIG. 2 is a diagram showing a hot air heater for detecting defects in the exhaust passage, and FIG. 3 is a perspective view showing a state in which a thermostat is attached to an exhaust port cap.

The supply/exhaust pipe (1) is attached to the wall (B), and has two vibes (la) and (lb) arranged coaxially, with an inner passage (IC) for exhaust and an outer passage (1d) for exhaust. It is used as air supply. In addition, the above-mentioned supply and exhaust pipe (1) has an inner passage (I
Two exhaust gas inlets (Ie) (II') communicating with C)
), and either one of the exhaust gas inlets (le) (], f') is connected to the exhaust vibrator (2) depending on the installation position of the hot air heater (^). Ru.

An exhaust port cap (4) is inserted into the unused exhaust gas inlet (II'). Further, an air supply hose (3) is connected to the outer passageway (1d).

A normally open contact type thermostat (5) is attached to this exhaust port cap (4). The operating temperature of this thermostat (5) is set below the temperature of the exhaust gas inlet (le) (If) when the exhaust path is in a normal state.

The air supplied by the air supply and exhaust pipe (1) is introduced into the combustion chamber (6) through the air supply hose (3), etc.
In 6), the gas etc. supplied from the electromagnetic pump (7) is combusted. The combustion gas passes through a heat exchanger (9) that communicates with the upper part of the combustion chamber (6), and in this heat exchanger (9) heat exchange is forcibly performed with air blown by a convection fan (8). . Then, the exhaust gas is discharged outdoors through the exhaust vibrator and the supply/exhaust tube (1).

FIG. 1 is a circuit diagram showing an embodiment of the exhaust path defect detection device of the present invention.

The thermostat (5) is connected in parallel to the normally closed contacts (10a) (10b) of the electromagnetic relay 00), and is connected to the control circuit (11)'s female terminals 01a) (llb). Further, an electromagnetic pump (7) is connected to the output terminal (I le) of the control circuit (11), and a drive terminal (llc) (11
A convection fan (8) and an electromagnetic relay (10) are connected to d).

The operation of the exhaust path defect detection device is as follows.

The combustion chamber (6) is warmed by gas combustion after ignition, and after the temperature of the combustion chamber (6) rises to an appropriate temperature, the control circuit (11) drives the convection fan (8) and the electromagnetic relay 001, and
Electrify the thermostat (5). At this point, the exhaust gas has reached the exhaust gas inlet (le) (Ir), and there are abnormalities in the exhaust path (disconnection between the supply and exhaust pipe (1) and exhaust vibrator (2), and the exhaust cap (4) The thermostat (5) is warmed to the operating temperature unless there is a hole in the air supply/exhaust tube (1) or exhaust vibrator (2), etc.). Since the thermostat (5) has been warmed up to the operating temperature as described above, the terminals (Ila) and (Ia) of the control circuit (11)
lb) to supply current to the control circuit (11).

Then, the electromagnetic relay 00) driven by the control circuit (11) opens the contact (10a). From this, the control circuit (1
1) is in a state where it is possible to detect an abnormality in the exhaust path.

When a current is supplied from the thermostat (5), the control circuit (11) determines that there is no abnormality in the exhaust path and continues the combustion operation.

However, if exhaust gas is leaking due to the supply/exhaust pipe (1) coming off or having a hole, the exhaust cap (4) coming off, or the exhaust vibrator (2) having a hole, etc., the convection fan should be closed after ignition. ) until the temperature of the exhaust cap (4) does not rise to the operating temperature of the thermostat (5).
The control circuit (11) is not energized. Therefore, in this case, it is determined that there is an abnormality in the exhaust path, and the safety circuit is activated to stop the electromagnetic pump (7).

In addition, if the exhaust gas leaks due to, for example, the supply and exhaust pipe (1) and exhaust vibrator (2) coming off during operation, the supply and exhaust pipe (1)
As the temperature of 1) decreases, the thermostat (5) turns O.
Becomes FF. In this case, power supply to the control circuit (11) is stopped. Therefore, it is determined that there is an abnormality in the exhaust path, and the safety circuit is activated to stop the electromagnetic pump (7).

In the above embodiment of the present invention, the thermostat (5) is attached to the exhaust port cap (4), and the thermostat (5) is attached to the exhaust port cap (4).
), the air supply/exhaust pipe (1) and exhaust vibro come off, the exhaust cap (4) comes off, and the air supply/exhaust pipe (
1) and the exhaust vibrator (2), there is no risk of electrolytic corrosion of the supply/exhaust tube (1) or the exhaust vibrator (2). In addition, since it is possible to detect the removal of the exhaust port cap (4), there is no need to take safety measures such as welding the exhaust port cap (4) (thereby reducing the labor required for installing the exhaust pipe). can.

FIG. 4 is a circuit diagram showing another embodiment, and the difference from the embodiment shown in FIG.
2) It uses (thermistor, temperature IC, etc.) and does not use electromagnetic relay 00).

A microcomputer is incorporated in the control circuit (11), and controls the electromagnetic pump (7), convection fan G), etc. according to the flowchart shown in FIG. That is, in step (2), ignition is detected, and in step (2), the elapse of a certain period of time is waited.

If it is determined that a certain period of time has elapsed, in step (3), the temperature data T supplied from the temperature sensor (12) is
Compare I with the preset temperature TO, and find that T1≧T
If O, repeat the process of step ■, and TI < T
If o, it is determined in step (2) that an abnormality has occurred in the exhaust path.

In step (2), driving of the electromagnetic pump (7) is stopped.

For the certain period of time in step ■ above, if the exhaust path is normal,
The time is set at which the temperature T1 detected by the temperature sensor (12) reaches a preset temperature TO.

Note that the present invention is not limited to the above-mentioned embodiments; for example, the temperature sensor (12) and the thermostat (5) may be connected to the exhaust gas inlet of the supply/exhaust pipe (1) in addition to the exhaust port cap (4). It can be attached to the inner passage (tc) leading to the exhaust port, and it can also be applied to an exhaust pipe in which an air supply path and an exhaust path are provided separately.

<Effects of the Invention> As described above, according to the exhaust path defect detection device of the present invention, when the exhaust pipe becomes detached from the exhaust pipe or a hole is formed in the exhaust path and the exhaust path becomes defective, The temperature detection means attached to the exhaust stack detects the temperature of the exhaust gas and outputs it to the exhaust path failure detection means, and the exhaust path failure detection means compares the detection output from the temperature detection means with preset temperature characteristic conditions. By comparing the values, it is possible to detect a defect in the exhaust path without energizing the exhaust path. Therefore,
It is possible to obtain the effect that even holes in the exhaust passage can be detected without electrolytically corroding the exhaust passage.

Additionally, by attaching a temperature detection means to the cap inserted into the exhaust gas inlet, it is possible to detect when the cap comes off, eliminating the need to weld the cap and reducing the labor required to install the exhaust pipe. be able to.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing an embodiment of the present invention, Figure 2 is a schematic configuration diagram of a hot air heater for detecting defects in the exhaust path, and Figure 3 is a diagram showing a thermostat attached to the exhaust port cap. FIG. 4 is a circuit diagram showing another embodiment; FIG. 5 is a flowchart of a control circuit; FIG. 6 is a diagram showing a conventional air supply and exhaust pipe disconnection detection device. (1)... Supply and exhaust pipe, (le) (if)... Exhaust gas inlet, (5)... Thermostat, 00)...
Electromagnetic relay, (11)...control circuit, (12)...
Temperature sensor patent applicant: Daikin Industries, Ltd. Representative: Hiroshi Kamei, patent attorney
Katsu (and 1 other person) Figure 1 Figure 4

Claims (1)

[Claims] 1. In a hot air heating device of a forced air supply/exhaust type in which an exhaust stack for discharging exhaust gas after combustion to the outside is connected to a hot air heater body placed indoors, , a temperature detection means for detecting the temperature of the exhaust gas, and an exhaust path defect detection means for detecting a defect in the exhaust passage by comparing the detection output of the temperature detection means with preset temperature characteristic conditions. Features: Exhaust path defect detection device. 2. The exhaust stack has a plurality of exhaust gas introduction ports, and a cap is inserted into the exhaust gas introduction port that is not connected to the hot air heater main body among the plurality of exhaust gas introduction ports,
The exhaust path failure detection device according to claim 1, wherein the temperature detection means is attached to the cap.