JPH0351629Y2 - - Google Patents

Description

[Detailed description of the invention] <Technical field> The present invention relates to a connection failure detection device for an exhaust pipe that guides gas generated in the main body to a predetermined location such as outdoors. Although it is widely applied in various fields, it is suitable for use in, for example, the supply and exhaust pipes of combustion machines such as oil hot air heaters.

<Prior art> For example, in a forced air supply/exhaust type kerosene heater, as shown in Fig. 3, the combustion part (not shown) inside the main body 1 is connected to the outside through a supply/exhaust pipe 1', and air necessary for combustion is communicated with the outside. All exhaust gases after combustion are exchanged with the outdoors to prevent indoor air pollution from exhaust gases.

Referring to FIG. 3 in detail, reference numeral 1 denotes a combustion machine main body (also referred to as main body) 1 having a combustion section inside, and has an air supply port 2 and a metal exhaust port 3 on the back surface.
Reference numeral 4 denotes a metal supply/exhaust tube that penetrates the wall 5 and opens to the outdoors, and has an air supply hole 6 and an exhaust hole 7. A metal exhaust pipe 8 communicates with the exhaust hole 7 of the supply/exhaust tube 4, and is connected to the exhaust port 3 of the main body. Reference numeral 9 denotes a metal air supply pipe that communicates with the air supply hole 6 of the air supply/exhaust tube 4, and 10 indicates a flexible air supply hose that communicates the air supply pipe 9 with the air supply port 2 of the main body.

Operation description: Combustion air is taken in from the air supply hole 6 of the air supply and exhaust pipe 4, and is passed through the air supply pipe 9 and air supply hose 10 to the air supply port 2.
The fuel is supplied into the main body 1, mixed with fuel in a burner (not shown), and combusted. The exhaust gas after combustion undergoes heat exchange with a heat exchanger (not shown), and is discharged from the exhaust port 3 through the exhaust pipe 8 to the outside from the exhaust hole 7 of the supply/exhaust pipe 4. Although the exhaust gas has a considerably higher concentration of CO, CO ₂ , NO _x , etc. than normal air components, the indoor air was not contaminated because it was discharged outdoors.

The supply/exhaust pipe 1' is between the exhaust pipe 8, the connection port 3, and the supply/exhaust pipe 4, between the supply/exhaust pipe 4 and the supply/exhaust pipe 9,
The air supply hose 10, the air supply pipe 9, and the air supply port 2 are connection points that can be connected to and separated from each other. Therefore, when installing during the heating season, it is necessary to arrange the supply and exhaust pipes 1' as shown in FIG. 3 and to connect each connection point airtightly. Such connection work is easy if performed according to a predetermined procedure, and connection errors will not occur, but it cannot be said that connection failures due to errors or the like will not occur.

In addition, when an external force is applied that causes the main body 1 to move, such as in an earthquake or when an object or person hits the main body 1, there is no guarantee that the joints of the air supply and exhaust pipes 1' will become disconnected.
Moreover, since the supply and exhaust pipe 1' is located behind the main body 1,
Even if a connection failure or disconnection occurs, it may not be easily noticed.

Such connection failures or disconnections will prevent air supply and exhaust from working properly, leading to poor combustion and lowering combustion efficiency.What is especially problematic is exhaust gas leaking into the room from the exhaust pipe side. This is the case. In other words, the exhaust gas contains CO, CO ₂ ,
Contains components such as NO _x in considerable concentrations, so if combustion continues under these conditions, the O ₂ concentration in the indoor air will decrease and the CO, CO ₂ and NO _x concentrations will increase, resulting in a significant increase. In some cases, it may cause an accident that could be life-threatening.

Therefore, it is most desirable to prevent poor connection or disconnection of the supply and exhaust pipe 1', but when considering conditions such as simplifying the installation work and removing it outside the heating season, the third It is not possible to drastically change the connection form shown in the figure and eliminate the connection points.

If so, in the unlikely event that a connection failure or disconnection occurs in the supply and exhaust pipe 1', especially on the exhaust pipe side, this should be detected immediately and the user notified, or combustion should be stopped to prevent an accident. The goal is to prevent this from happening.

Therefore, it has already been proposed to be able to detect poor connection or disconnection in the supply and exhaust pipes, particularly on the exhaust pipe side.

That is, in FIG. 3, the main body 1, the exhaust port 3, the exhaust pipe 8, the supply/exhaust pipe 4, and the air supply pipe 9 are all made of a conductive metal material such as stainless steel or aluminum. The air supply hose 10 has a coiled wire 11 and electrically connects the air supply pipe 9 and the lead wire 12. The other end of the lead wire 12 is electrically insulated from the main body 1 and connected to the control section 1, which will be described later.
Connected to 3.

FIG. 2 is a block diagram of the control section 13, in which 1 represents the main body. 14 is a 100V commercial AC power supply,
15 is an isolation transformer that reduces the voltage to about 24V. 1
6 is the voltage-dropped AC voltage as a DC voltage,
This is a power supply circuit that supplies various parts, and a DC voltage of about -24V is supplied from the + terminal to the air supply port 3. This voltage is supplied to the main body 1, which is a conductive material, to the pipes 8, 4, 9, and to the wire 11 in the air supply hose 10, which is represented as a switch 17 in FIG. This voltage is connected to the - terminal via the lead wire 12 and a resistor R in the control section 13. That is, +, -
A conductive path is formed between the terminals. 18 is a voltage judgment circuit, and the voltage across the resistor R is a predetermined voltage (-7V).
It is determined whether it is approximately equal to or zero, and if it becomes zero, a connection failure signal P is generated. Specifically, a comparator that is turned on and off depending on the voltage across the resistor R is used. Reference numeral 19 denotes a control circuit which, upon receiving the signal P, drives a notification means 20 such as a buzzer or a lamp, and immediately stops combustion by sending a combustion stop signal to a combustion control circuit (not shown).

Therefore, if there is no defect in the connection of the supply and exhaust pipe 1',
When AC power is applied, DC current (approx. 0.3mA)
+ terminal → switch 17 → lead wire 12 → resistor R
→ flows through the route of the − terminal, a predetermined voltage is generated across the resistor R, and this is read by the voltage determination circuit 18, so the signal P is not generated. In other words, it is determined that there is no connection failure and normal combustion control is performed.

On the other hand, if there is a connection failure, for example, a disconnection, in the supply/exhaust pipe 1', the switch 17 will be in the "open" state, so a predetermined voltage will not be generated across the resistor R, and the determination circuit 18 will output a connection failure signal. Generate P. Therefore, the control circuit 19 drives the notification means 20 to actively notify the user of the poor connection, and if combustion is in progress, immediately stops the combustion to prevent the generation of exhaust gas.

In this way, a connection failure can be detected immediately, and accidents caused by exhaust gas can be prevented.

<Problems to be Solved> However, with this configuration, as shown in Fig. 1, there is no problem in the event that the exhaust cap 22 provided on the supply/exhaust pipe 21, which normally allows connection of exhaust pipes from two directions, comes off. In this case, since the exhaust cap 22 itself has no role in the conductive path, even if the cap 22 comes off, there is no change in the circuit state, and therefore it cannot be detected.

<Means for solving the problem> In FIG. 1, the air supply port of the supply/exhaust tube 21 and the air supply pipe 9 are electrically insulated and connected, and the exhaust cap 22 and the air supply pipe 9 are connected by a lead wire. 23 for electrical connection.

<Function> Even if the exhaust cap 22 is removed, the supply and exhaust pipe 21
Even if the exhaust pipe 8 comes off, the conductive path is cut off, so any of the above-mentioned detachments can be detected.

<Example> FIG. 1 is a configuration diagram of the main parts of the present invention, and the only difference from FIG. 2 and FIG. 3 is the configuration of the supply and exhaust pipe 21 and the connection configuration with the air supply pipe 9. The explanation of this part will be omitted and only the main parts will be explained.

In FIG. 1, reference numeral 21 denotes a supply and exhaust pipe having two exhaust pipe connection ports 21a and 21b;
An exhaust pipe 8 is airtightly connected to 1a. 22
is a conductive exhaust cap that is removably and airtightly placed over the unused connection port 21b.

24 is an air supply connection port (conductor) coming out of the supply/exhaust pipe 21, and 25 is an insulating air supply elbow for connecting the air supply connection port 24 and the air supply pipe 9.

26 is a conductive angle attached to the air supply pipe 9, and the angle 26 and the exhaust cap 2
2 are electrically connected by lead wires 23.

Under the above configuration, when a potential (-24V) is applied to the stove body 1 from the circuit inside the stove body 1, that potential will be transferred from the stove body 1 to the exhaust gas if the supply and exhaust pipes etc. are connected correctly. It passes through the pipe 8 -> air supply/exhaust tube 21 -> exhaust cap 22 -> lead wire -> angle 26 -> air supply pipe 9 -> wire 11 -> lead wire 12 and is connected to the judgment circuit inside the main body, which determines that it is in a normal state. If the supply/exhaust pipe 21, exhaust cap 22, etc. come off, the electric potential (-24V) applied to the main body will no longer be applied to the judgment circuit inside the stove main body because the above-mentioned closed circuit will be destroyed. As described above, it is determined that there is an abnormal condition and the operation of the stove is stopped.

<Effects> According to the present invention, not only the dislodgement of the exhaust pipe but also the dislodgement of the exhaust cap can be detected.

Furthermore, since the detection is performed electrically, it is easy to use this connection failure signal to proactively notify the user of the problem or to stop the generation of exhaust gas. Accidents can be prevented.

[Brief explanation of the drawing]

FIG. 1: External side view of main parts of an embodiment of the present invention.
Figure 2: Main part block diagram of the defect detection device for supply and exhaust pipes. Figure 3: External side view of the conventional device. Code, 21... Supply and exhaust pipe, 22... Exhaust cap, 23... Lead wire, 25... Exhaust elbow.

Claims (1)

[Scope of claim for utility model registration] An air supply port for taking in combustion air from the outside,
A forced air supply/exhaust type hot air heater main body having an exhaust port for discharging exhaust gas generated by combustion;
A conductive air supply pipe and a conductive exhaust pipe are connected to the air supply and exhaust ports and serve as passages for combustion air and exhaust gas, and are further connected to the air supply and exhaust pipes to connect indoors and outdoors. A forced supply/exhaust type comprising a conductive supply/exhaust pipe having at least two or more exhaust pipe connection ports that communicate with each other, and a conductive exhaust cap provided at the exhaust pipe connection port of the supply/exhaust pipe. In the combustion machine, the above-mentioned supply/exhaust pipe and the air supply pipe are electrically insulated and connected, and the above-mentioned exhaust cap and the air supply pipe are electrically connected with a lead wire, and the above-mentioned exhaust pipe, supply/exhaust pipe, and exhaust pipe are connected electrically. A conductive path is formed by a cap, a lead wire, and an air supply pipe, a power supply circuit is provided to apply a predetermined voltage to this conductive path, and a voltage detection means is provided to detect voltage changes in the conductive path. defect detection device.