Combustion device

Abstract

To provide a combustion device that can improve combustion efficiency even when the pressure of the air supplied to the furnace is monitored by an air pressure switch. [Solution] In the combustion apparatus 1000 of this disclosure, a temperature sensor 9 is installed inside the furnace 1 for combustion and detects the temperature inside the furnace 1. A blower 6 supplies air into the furnace 1 via an air supply pipe 4. An air pressure switch 7 is installed in the middle of the air supply pipe 4 and outputs an equipment malfunction signal when the pressure of the air supplied from the blower 6 falls below a set pressure. An air supply prevention mechanism 8 is installed downstream of the air pressure switch 7 in the air supply pipe 4 and switches between preventing the supply of air from the blower 6 into the furnace 1 or supplying air from the blower 6 into the furnace 1, depending on the temperature inside the furnace 1.

Description

Technical Field

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[0001] The present invention relates to a combustion device.

Background Art

[0002] In Patent Document 1, regarding the ignition pre-purge (air purge) of a gas combustion furnace, a technique for omitting the purge when the off-time does not exceed a predetermined time is disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

[0007] The combustion apparatus of this disclosure includes a temperature sensor installed in a furnace for combustion and detecting the furnace temperature, a blower that supplies air to the furnace via an air supply pipe, an air pressure switch installed in the middle of the air supply pipe and outputting an equipment malfunction signal when the pressure of the air supplied from the blower falls below a set pressure, and an air supply prevention mechanism installed downstream of the air pressure switch in the air supply pipe and switching whether to prevent the supply of air from the blower to the furnace or to supply air from the blower to the furnace depending on the furnace temperature.

[0008] Furthermore, in combustion apparatuses according to other embodiments of this disclosure, the air supply prevention mechanism is a three-way valve that switches, depending on the furnace temperature, between releasing air from the blower to the outside of the air supply pipe or supplying air supplied from the blower into the furnace.

[0009] Furthermore, in combustion apparatuses according to other embodiments of the present disclosure, the air supply prevention mechanism is a shut-off valve that, depending on the furnace temperature, shuts off the supply of air from the blower to the furnace, or switches whether to supply air from the blower to the furnace.

[0010] In the above configuration, by installing an air supply prevention mechanism (three-way valve or shut-off valve) downstream of the air pressure switch in the air supply pipe, air purging can be omitted even when the pressure of the air supplied to the furnace is monitored by the air pressure switch, thereby improving combustion efficiency.

[0011] Furthermore, a combustion apparatus according to another aspect of the present disclosure includes an air flow rate adjustment mechanism capable of adjusting the flow rate of air supplied into the furnace by the blower, wherein when the shut-off valve shuts off the supply of air from the blower into the furnace, the air flow rate adjustment mechanism lowers the flow rate of air supplied into the furnace by the blower than when the shut-off valve supplies air from the blower into the furnace.

[0012] In the above configuration, by adjusting the airflow rate in this way, the load on the shut-off valve caused by shutting off the air can be reduced.

[0013] Furthermore, a combustion apparatus according to another aspect of the present disclosure includes an air flow rate adjustment mechanism capable of adjusting the flow rate of air supplied into the furnace by the blower, wherein when the shut-off valve shuts off the supply of air from the blower to the furnace, the air flow rate adjustment mechanism adjusts the flow rate of the air supplied from the blower so that the pressure of the air supplied does not fall below the set pressure of the air pressure switch.

[0014] In the above configuration, by adjusting the airflow rate in this way, the load on the shut-off valve from cutting off the air supply can be reduced without the air pressure switch outputting an equipment malfunction signal. [Effects of the Invention]

[0015] This disclosure provides a combustion apparatus that can improve combustion efficiency even when the pressure of the air supplied to the furnace is monitored by an air pressure switch. [Brief explanation of the drawing]

[0016] [Figure 1] This figure shows an example of the configuration of a combustion device according to the first embodiment. [Figure 2] This is a flowchart showing an example of the operation of the combustion device according to the first embodiment. [Figure 3]It is a diagram comparing the presence or absence of the air flow rate of the supply to the inside of furnace 1 between when combustion is OFF and when combustion is ON, between the combustion device according to the first embodiment and the combustion device according to the comparative example. [Figure 4] It is a diagram showing an example of the configuration of the combustion device according to the second embodiment. [Figure 5] It is a flowchart showing an example of the operation of the combustion device according to the second embodiment. [Figure 6] It is a diagram comparing the presence or absence of the air flow rate of the supply to the inside of furnace 1 between when combustion is OFF and when combustion is ON, between the combustion device according to the second embodiment and the combustion device according to the comparative example.

Mode for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same or corresponding elements are denoted by the same reference numerals, and redundant descriptions are omitted as necessary for clarity of explanation.

[0018] (First Embodiment) First, the configuration of the combustion device 1,000 according to the first embodiment will be described using FIG. 1.

[0019] FIG. 1 is a diagram showing an example of the configuration of the combustion device 1,000 according to the first embodiment. As shown in FIG. 1, the combustion device 1,000 includes a furnace 1, a burner 2, a fuel gas supply pipe 3, an air supply pipe 4, a fuel gas shutoff valve 5, a blower 6, an air pressure switch 7, a three-way valve (air supply prevention mechanism) 8, a temperature sensor 9, an ignition transformer 21, a burner control device 100, and an air supply control device 200. Here, the combustion device 1,000 is composed of devices conforming to JIS B8415.

[0020] In the combustion device 1,000, the burner control device 100 controls the burner 2, the fuel gas shutoff valve 5, the blower 6, the air pressure switch 7, and the ignition transformer 21. Further, the air supply control device 200 controls the temperature sensor 9 and the three-way valve 8.

[0021] Furnace 1 is an industrial combustion furnace. Burner 2 is installed inside furnace 1. Burner 2 uses fuel to perform combustion inside furnace 1. Ignition transformer 21 is also installed inside burner 2. Ignition transformer 21 ignites the fuel supplied to burner 2.

[0022] The temperature sensor 9 is installed inside the furnace 1. For example, the temperature sensor 9 is installed near the burner 2. The temperature sensor 9 detects the temperature inside the furnace 1.

[0023] The fuel gas supply pipe 3 is connected to the burner 2. The fuel gas supply pipe 3 supplies fuel gas to the burner 2. The fuel gas is, for example, hydrogen gas. The air supply pipe 4 is connected to the burner 2. The air supply pipe 4 supplies air into the furnace 1 via the burner 2. The air supply pipe 4 is used for air purging (supplying air to remove residual gases from inside the furnace 1).

[0024] The fuel gas shut-off valve 5 is installed in the fuel gas supply pipe 3. The fuel gas shut-off valve 5 can shut off the fuel gas supplied from the fuel gas supply source (not shown) to the burner 2.

[0025] Blower 6 is connected to air supply pipe 4. Blower 6 supplies air into furnace 1. The air pressure switch 7 is installed in the air supply pipe 4 downstream of the blower 6 (i.e., on the furnace 1 side). The air pressure switch 7 monitors whether the pressure of the air supplied into the furnace 1 falls below the set pressure. Specifically, when the pressure of the air supplied from the blower 6 is equal to or greater than the set pressure, the air pressure switch 7 turns ON and sends an ON signal to the burner control device 100. On the other hand, when the pressure of the air supplied from the blower 6 falls below the set pressure, the air pressure switch 7 turns OFF and sends an OFF signal, i.e., an equipment malfunction signal, to the burner control device 100.

[0026] The three-way valve 8 is installed downstream of the air pressure switch 7 in the air supply pipe 4. The three-way valve 8 is a valve that has three ports (for example, one inlet and two outlets) and can set two air flow paths. The three-way valve 8 can set the air flow path to either "inside the furnace 1" or "outside the air supply pipe 4 (i.e., outside the furnace 1)".

[0027] The three-way valve 8 switches between preventing the supply of air from the blower 6 into the furnace 1, or supplying air from the blower 6 into the furnace 1, depending on the internal temperature of the furnace 1 detected by the temperature sensor 9.

[0028] The burner control device 100 is a computer. The burner control device 100 controls the switching between ON and OFF of combustion. The burner control device 100 also controls the blower 6 to perform air purging in the furnace 1. The burner control device 100 also monitors the air pressure switch 7. Specifically, if the burner control device 100 receives an equipment malfunction signal from the air pressure switch 7, it stops the operation of the system (for example, the combustion operation in the furnace 1).

[0029] The air supply control device 200 is a computer. The air supply control device 200 controls the three-way valve 8 to either prevent the supply of air from the blower 6 into the furnace 1, or to supply air from the blower 6 into the furnace 1, according to the temperature inside the furnace 1 detected by the temperature sensor 9.

[0030] Next, the operation of the combustion device 1000 according to the first embodiment will be explained using Figure 2.

[0031] Figure 2 is a flowchart showing an example of the operation of the combustion device 1000 according to the first embodiment. As shown in Figure 2, first, in step S101, the burner control device 100 switches the combustion to OFF. In this case, the burner control device 100 shuts off the supply of fuel gas to the burner 2 by closing the fuel gas shut-off valve 5, and the burner 2 extinguishes the fire.

[0032] Next, in step S102, the air supply control device 200 determines whether the temperature inside the furnace 1 detected by the temperature sensor 9 is equal to or greater than the spontaneous combustion temperature (set temperature). The spontaneous combustion temperature is the ignition point, which is the lowest temperature at which a substance spontaneously ignites without an external ignition source.

[0033] If it is determined that the temperature inside furnace 1 is above a predetermined self-combustion temperature (YES in step S102), the process proceeds to step S103. In step S103, the air supply control device 200 sets the flow path of the three-way valve 8 to face outwards from the air supply pipe 4. By doing so, the three-way valve 8 releases the air supplied from the blower 6 to the outside of the air supply pipe 4 (i.e., prevents it from being supplied into furnace 1). Therefore, air purging into furnace 1 is omitted. The process then proceeds to step S106.

[0034] On the other hand, if it is determined that the furnace temperature is below a predetermined self-combustion temperature (NO in step S102), the process proceeds to step S104. In step S104, the air supply control device 200 sets (or maintains) the flow path of the three-way valve 8 toward the inside of the furnace 1. By doing so, the three-way valve 8 supplies air supplied from the blower 6 into the furnace 1. Next, in step S105, air purging into the furnace 1 is performed. After that, the process proceeds to step S106.

[0035] In step S106, the burner control device 100 determines whether the re-ignition condition is met. If the re-ignition condition is met (YES in step S106), the process proceeds to step S107. On the other hand, if the re-ignition condition is not met (NO in step S106), the process returns to step S106.

[0036] In step S107, the air supply control device 200 determines whether the temperature inside the furnace 1 is above the self-combustion temperature. If it is determined that the temperature inside furnace 1 is above a predetermined self-combustion temperature (YES in step S107), the process proceeds to step S108. In step S108, the air supply control device 200 sets the flow path of the three-way valve 8 to "outward direction of air supply pipe 4". By doing so, the three-way valve 8 releases the air supplied from the blower 6 to the outside of the air supply pipe 4 (i.e., prevents it from being supplied into furnace 1). Therefore, air purging into furnace 1 is omitted. The process then proceeds to step S111.

[0037] On the other hand, if it is determined that the temperature inside the furnace 1 is below a predetermined self-combustion temperature (NO in step S107), the process proceeds to step S109. In step S109, the air supply control device 200 sets (or maintains) the flow path of the three-way valve 8 to "into the furnace 1 direction". By doing so, the three-way valve 8 supplies air supplied from the blower 6 into the furnace 1. Next, in step S110, air purging into the furnace 1 is performed. After that, the process proceeds to step S111.

[0038] In step S111, the air supply control device 200 terminates the air purging-related operations. Next, in step S112, the air supply control device 200 sets (or maintains) the flow path of the three-way valve 8 toward the inside of the furnace 1. Next, in step S113, the burner control device 100 switches combustion ON. In this case, the burner control device 100 supplies fuel gas to the burner 2 by opening the fuel gas shut-off valve 5, and the ignition transformer 21 ignites the fuel gas supplied to the burner 2. After that, the series of processes is completed.

[0039] Next, an example of the effects of the combustion device 1000 according to the first embodiment will be explained using Figure 3.

[0040] Figure 3 is a diagram comparing the presence or absence of air flow rate supplied into the furnace 1 between combustion OFF and combustion ON in the combustion apparatus 1000 according to the first embodiment and the combustion apparatus according to the comparative example. Figure 3 (bottom) relates to the combustion apparatus 1000 according to the first embodiment. Figure 3 (top) relates to the combustion apparatus according to the comparative example. Here, the combustion apparatus according to the comparative example does not include a three-way valve 8 and an air supply control device 200 that controls the three-way valve 8.

[0041] In Figure 3 (top) and Figure 3 (bottom), the horizontal axis represents time, and the vertical axis represents the following: • Turning the burner control device 100 ON / OFF • Turning the air pressure switch 7 ON / OFF • Presence or absence of fuel gas flow rate supplied to burner 2 • Presence or absence of air flow rate for supplying inside Furnace 1 Furthermore, Figure 3 (below) shows the following on the vertical axis. • Turning the three-way valve 8 ON / OFF • Presence or absence of air flow rate for discharge outside Furnace 1

[0042] As shown in Figure 3 (above), in the comparative example combustion apparatus, if the supply of air to the furnace 1 is stopped between combustion OFF and combustion ON, the air pressure switch 7 outputs an equipment malfunction signal, making it impossible to stop the air. As a result, the inside of the furnace 1 is cooled by the air, and the combustion efficiency decreases.

[0043] On the other hand, as shown in Figure 3 (below), the combustion device 1000 according to the first embodiment can release air to the outside of the furnace 1 and prevent the supply of air to the furnace 1 under predetermined temperature conditions between combustion OFF and combustion ON. Therefore, in the combustion device 1000, the inside of the furnace 1 is not cooled by air, and combustion efficiency can be improved.

[0044] (Second embodiment) Next, the configuration of the combustion device 2000 according to the second embodiment will be described using Figure 4. Figure 4 is a block diagram showing an example of the configuration of the combustion device 2000 according to the second embodiment.

[0045] As shown in Figure 4, the combustion device 2000 has the following configuration changes from the combustion device 1000 according to the first embodiment. In addition, the combustion device 2000 is equipped with a shut-off valve (air supply prevention mechanism) 11 instead of a three-way valve 8. The combustion device 2000 is further equipped with an air flow rate adjustment mechanism 12. In addition, the combustion device 2000 is equipped with an air supply control device 300 instead of an air supply control device 200.

[0046] The shut-off valve 11 is installed downstream of the air pressure switch 7 in the air supply pipe 4. The shut-off valve 11 has two ports (one inlet and one outlet) and is a valve that can switch the air shut-off ON / OFF. The shut-off valve 11 switches between shutting off the supply of air from the blower 6 to the furnace 1 or supplying air from the blower 6 to the furnace 1, depending on the temperature inside the furnace 1 detected by the temperature sensor 9.

[0047] The air flow rate adjustment mechanism 12 is a mechanism capable of adjusting the flow rate of air supplied into the furnace 1 by the blower 6. Specifically, the air flow rate adjustment mechanism 12 receives a blower frequency signal from the air supply control device 300, controls the rotational speed of the blower 6 according to the blower frequency signal, and adjusts the flow rate of air supplied into the furnace 1. More specifically, when the shut-off valve 11 shuts off the supply of air from the blower 6 to the furnace 1, the air flow rate adjustment mechanism 12 adjusts the flow rate of air supplied into the furnace by the blower 6 to be lower than when air is supplied into the furnace 1. Furthermore, when the shut-off valve 11 shuts off the supply of air from the blower 6 to the furnace 1, the air flow rate adjustment mechanism 12 adjusts the flow rate of air supplied into the furnace by the blower 6 so that the pressure of the air supplied from the blower 6 does not fall below the set pressure of the air pressure switch 7.

[0048] The air supply control device 300 is a computer. The air supply control device 300 controls the temperature sensor 9, the shut-off valve 11, and the air flow rate adjustment mechanism 12.

[0049] Next, the operation of the combustion device 2000 according to the second embodiment will be explained using Figure 5.

[0050] Figure 5 is a flowchart showing an example of the operation of the combustion device 2000 according to the second embodiment. As shown in Figure 5, first, in step S201, the burner control device 100 switches the combustion to OFF. In this case, the burner control device 100 shuts off the supply of fuel gas to the burner 2 by closing the fuel gas shut-off valve 5, and the burner 2 extinguishes the fire.

[0051] Next, in step S202, the air supply control device 300 determines whether the temperature inside the furnace 1 detected by the temperature sensor 9 is equal to or greater than the self-combustion temperature (set temperature).

[0052] If it is determined that the temperature inside furnace 1 is above a predetermined self-combustion temperature (YES in step S202), the process proceeds to step S203. In step S203, the air supply control device 300 transmits a blower frequency signal to the air flow rate adjustment mechanism 12, causing it to set the air flow rate supplied from blower 6 to "low". By doing so, the air flow rate adjustment mechanism 12 adjusts the air flow rate supplied into furnace 1 by blower 6 to a flow rate corresponding to "low". However, the air flow rate set to "low" in step S203 is such that, when the supply of air to furnace 1 is shut off by the shut-off valve 11, the pressure of the air supplied from blower 6 is equal to or greater than the set pressure of the air pressure switch 7 (i.e., no equipment malfunction signal is output).

[0053] Next, in step S204, the air supply control device 300 sets the shut-off valve 11 to "ON". By doing so, the shut-off valve 11 shuts off the supply of air from the blower 6 into the furnace 1. Therefore, air purging into the furnace 1 is omitted. The process then proceeds to step S208.

[0054] On the other hand, if it is determined that the temperature inside the furnace 1 is below a predetermined self-combustion temperature (NO in step S202), the process proceeds to step S205. In step S205, the air supply control device 300 sets (or holds) the shut-off valve 11 to "OFF". By doing so, the shut-off valve 11 supplies air supplied from the blower 6 into the furnace 1.

[0055] Next, in step S206, the air supply control device 300 transmits a blower frequency signal to the air flow rate adjustment mechanism 12, causing it to set the air flow rate supplied from the blower 6 to "high". By doing so, the air flow rate adjustment mechanism 12 adjusts the air flow rate supplied into the furnace 1 by the blower 6 to a flow rate corresponding to "high". Here, the air flow rate set in step S206 is higher than the air flow rate set in step S203. Next, in step S207, air purging into the furnace 1 is performed. After that, the process proceeds to step S208.

[0056] In step S208, the burner control device 100 determines whether the re-ignition condition is met. If the re-ignition condition is met (YES in step S208), the process proceeds to step S209. On the other hand, if the re-ignition condition is not met (NO in step S208), the process returns to step S208.

[0057] Next, in step S209, the air supply control device 300 determines whether the temperature inside the furnace 1 detected by the temperature sensor 9 is equal to or greater than the autocombustion temperature.

[0058] If it is determined that the temperature inside furnace 1 is above a predetermined self-combustion temperature (YES in step S209), the process proceeds to step S210. In step S210, the air supply control device 300 transmits a blower frequency signal to the air flow rate adjustment mechanism 12, causing it to set the air flow rate supplied from blower 6 to "low". By doing so, the air flow rate adjustment mechanism 12 adjusts the air flow rate supplied into furnace 1 by blower 6 to a flow rate corresponding to "low". However, the air flow rate set to "low" in step S210 is such that, when the supply of air to furnace 1 is shut off by the shut-off valve 11, the pressure of the air supplied from blower 6 is equal to or greater than the set pressure of the air pressure switch 7 (i.e., no equipment malfunction signal is output).

[0059] Next, in step S211, the air supply control device 300 sets the shut-off valve 11 to "ON". By doing so, the shut-off valve 11 shuts off the supply of air from the blower 6 into the furnace 1. Therefore, air purging into the furnace 1 is omitted. The process then proceeds to step S215.

[0060] On the other hand, if it is determined that the furnace temperature is below a predetermined self-combustion temperature (NO in step S209), the process proceeds to step S212. In step S212, the air supply control device 300 sets (or holds) the shut-off valve 11 to "OFF". By doing so, the shut-off valve 11 supplies air supplied from the blower 6 into the furnace 1.

[0061] Next, in step S213, the air supply control device 300 controls the air flow rate adjustment mechanism 12 to set the air flow rate supplied from the blower 6 to "high". By doing so, the air flow rate adjustment mechanism 12 adjusts the air flow rate supplied into the furnace 1 by the blower 6 to a flow rate corresponding to "high". Here, the air flow rate set in step S213 is higher than the air flow rate set in step S210. Next, in step S214, air purging into the furnace 1 is performed. After that, the process proceeds to step S215.

[0062] In step S215, the air supply control device 300 terminates the air purging-related operations. Next, in step S216, the air supply control device 300 sets (or holds) the shut-off valve 11 to OFF. Next, in step S217, the burner control device 100 switches combustion to ON. In this case, the burner control device 100 supplies fuel gas to the burner 2 by opening the fuel gas shut-off valve 5 and ignites the fuel gas supplied to the burner 2 by the ignition transformer 21. After that, the series of processes is completed.

[0063] Next, an example of the effects of the combustion device 2000 according to the second embodiment will be explained using Figure 6.

[0064] Figure 6 is a diagram comparing the presence or absence of air flow rate supplied to the furnace 1 between combustion OFF and combustion ON in the combustion apparatus 2000 according to the second embodiment and the combustion apparatus according to the comparative example. Figure 6 (bottom) relates to the combustion apparatus 2000 according to the second embodiment. Figure 6 (top) relates to the combustion apparatus according to the comparative example. Here, the combustion apparatus according to the comparative example does not have a shut-off valve 11, an air flow rate adjustment mechanism 12, and an air supply control device 300 that controls them.

[0065] In Figure 6 (top) and Figure 6 (bottom), the horizontal axis represents time, and the vertical axis represents the following: • Turning the burner control device 100 ON / OFF • Turning the air pressure switch 7 ON / OFF • Presence or absence of fuel gas flow rate supplied to burner 2 • Presence or absence of air flow rate for supplying inside Furnace 1 Furthermore, Figure 6 (below) shows the following on the vertical axis. • ON / OFF of shutoff valve 11 - Whether or not the airflow rate supplied from the blower 6 is adjusted ("low") by the airflow rate adjustment mechanism 12.

[0066] As shown in Figure 6 (above), in the comparative example combustion apparatus, if the supply of air to the furnace 1 is stopped between combustion OFF and combustion ON, the air pressure switch 7 outputs an equipment malfunction signal, making it impossible to stop the air. As a result, the inside of the furnace 1 is cooled by the air, and the combustion efficiency decreases.

[0067] On the other hand, as shown in Figure 6 (below), the combustion device 2000 according to the second embodiment can prevent the supply of air to the furnace 1 by shutting off the air supply with the shut-off valve 11 under predetermined temperature conditions between combustion OFF and combustion ON. Therefore, in the combustion device 2000, the inside of the furnace 1 is not cooled by air, and combustion efficiency can be improved. In addition, when the air is shut off by the shut-off valve 11, the air flow rate supplied from the blower 6 is adjusted to "low" by the air flow rate adjustment mechanism 12, so the load on the shut-off valve 11 that shuts off the air can be reduced.

[0068] It should be noted that the present invention is not limited to the embodiments described above, and can be modified as appropriate without departing from the spirit of the invention.

[0069] The computers comprising the burner control device 100, air supply control device 200, and air supply control device 300 include a processor and memory. The processor may be, for example, a microprocessor, an MPU (Micro Processing Unit), or a CPU (Central Processing Unit). The processor may include multiple processors. The memory consists of a combination of volatile memory and non-volatile memory. The memory may include storage located away from the processor. In this case, the processor may access the memory via an I / O interface not shown. The processor executes one or more programs that include a set of instructions for causing the computer to perform algorithms (operations) as described with reference to the drawings. The programs include a set of instructions (or software code) for causing the computer to perform one or more functions as described in the embodiments when loaded into the computer. The programs may be stored in a non-temporary computer-readable medium or a tangible storage medium. Examples, but not limited to, include computer-readable media or physical storage media such as random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drives (SSDs) or other memory technologies, CD-ROMs, digital versatile discs (DVDs), Blu-ray® discs or other optical disc storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices. Programs may be transmitted over temporary computer-readable media or communication media. Examples, but not limited to, include temporary computer-readable media or communication media such as electrical, optical, acoustic or other forms of propagating signals. [Explanation of Symbols]

[0070] 1 Furnace, 2 Burner, 3 Fuel gas supply pipe, 4 Air supply pipe, 5 Fuel gas shut-off valve, 6 Blower, 7 Air pressure switch, 8 Three-way valve (air supply prevention mechanism), 9 Temperature sensor, 11 Shut-off valve (air supply prevention mechanism), 12 Air flow rate adjustment mechanism, 21 Ignition transformer, 100 Burner control device, 200, 300 Air supply control device, 1000, 2000 Combustion device

Claims

1. A temperature sensor installed inside a furnace for combustion, which detects the temperature inside the furnace, A blower that supplies air into the furnace via an air supply pipe, An air pressure switch is installed in the middle of the air supply pipe and outputs an equipment malfunction signal when the pressure of the air supplied from the blower falls below a set pressure. The air supply pipe includes an air supply prevention mechanism installed downstream of the air pressure switch, which, depending on the furnace temperature, prevents the supply of air from the blower into the furnace, or switches whether to supply air from the blower into the furnace. Combustion device.

2. The aforementioned air supply prevention mechanism is This is a three-way valve that switches between releasing air from the blower to the outside of the air supply pipe or supplying air supplied from the blower into the furnace, depending on the furnace temperature. The combustion apparatus according to claim 1.

3. The aforementioned air supply prevention mechanism is This shut-off valve switches between shutting off the supply of air from the blower to the furnace, or supplying air from the blower to the furnace, depending on the furnace temperature. The combustion apparatus according to claim 1.

4. The furnace is equipped with an air flow rate adjustment mechanism that can adjust the flow rate of air supplied into the furnace by the blower, The aforementioned air flow rate adjustment mechanism is When the shut-off valve shuts off the supply of air from the blower to the furnace, the flow rate of air supplied to the furnace by the blower is lower than when the shut-off valve supplies air from the blower to the furnace. The combustion apparatus according to claim 3.

5. The furnace is equipped with an air flow rate adjustment mechanism that can adjust the flow rate of air supplied into the furnace by the blower, The aforementioned air flow rate adjustment mechanism is When the shut-off valve shuts off the supply of air from the blower to the furnace, the flow rate of the air is adjusted so that the pressure of the air supplied from the blower does not fall below the set pressure of the air pressure switch. The combustion apparatus according to claim 4.

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