JP6593632B2 - Combustion equipment - Google Patents

Description

  The present invention relates to a combustion apparatus capable of heating hot water with heat generated by combustion of fuel gas, and more particularly to a combustion apparatus that controls a combustion state according to a flame temperature.

  In the conventional combustion apparatus, a thermocouple is provided as a burner sensor for detecting the temperature of the flame, the burner sensor and the control means are arranged apart from each other, and the burner sensor and the control means of the combustion apparatus are connected via a relay connector. It was. The burner sensor and the relay connector are connected by a temperature compensating conductor, and the relay connector and the control means are connected by an inexpensive signal line that is not a temperature compensating conductor. Since the control means did not include the burner sensor reference contact compensation means, the temperature of the relay connector becomes the burner sensor reference contact temperature, and there is a deviation between the actual flame temperature and the flame temperature acquired by the control means. As a result, the control means could not obtain the flame temperature accurately.

  As a relay connector that eliminates this temperature shift, Patent Document 1 discloses a relay connector in which a compensation temperature sensor serving as a reference contact compensation means is mounted inside the connector.

JP-A-8-162220

  However, the relay connector as in Patent Document 1 is for connecting a plurality of temperature sensors to a measuring instrument at a time, and is not suitable for use in a combustion apparatus in which only one burner sensor is connected. Further, since the compensation temperature sensor is provided inside the connector, there is a problem that the manufacturing cost becomes high.

  Further, if one of the burner sensor and the compensating temperature sensor fails and the relay connector is replaced, the other sensor that has not failed is also replaced, resulting in waste.

  An object of the present invention is to provide a combustion apparatus that includes a reference junction compensation means that can be provided inexpensively and easily, and that can obtain an accurate flame temperature and can control combustion.

The combustion apparatus according to claim 1 is a combustion section, a flame temperature detection means for detecting a flame temperature generated in the combustion section, an atmosphere temperature detection means for detecting the temperature of the atmosphere, and a combustion state based on the detected flame temperature. The flame temperature detecting means is connected from the flame temperature detecting means to the relay connector with a temperature compensating conductor, and the signal from the relay connector to the control means is a combustion apparatus. Since the ambient temperature detection means is also used as a reference contact compensation means for the flame temperature detection means, the ambient temperature detection means is bound to a signal line from the control means to the relay connector. disposed in the relay connector near by, the control means, the flame temperature detected by the ambient temperature detected by said ambient temperature detection means And correcting the flame temperature detected by the stage.

According to a second aspect of the present invention, in the invention of the first aspect, the atmosphere temperature detecting means is fixed to the relay connector via a fixing bracket.

  According to the first aspect of the present invention, since the ambient temperature detecting means for detecting the ambient temperature also serves as the reference contact compensating means of the flame temperature detecting means, it is not necessary to separately provide a dedicated reference contact compensating means, and the ambient temperature detecting means The flame temperature acquired from the flame temperature detecting means can be easily and inexpensively corrected by the ambient temperature acquired from the above.

  Further, since the ambient temperature detecting means and the flame temperature detecting means are separately connected to the control means, when one is replaced, the other is not replaced together, and can be replaced separately.

Since the signal line connecting the relay connector and the control means and the signal line of the ambient temperature detecting means are bundled, the ambient temperature detecting means can be easily arranged near the relay connector.

According to the second aspect of the present invention, since the ambient temperature detection means is fixed to the relay connector via the fixing bracket, the ambient temperature detection means can be easily disposed in the vicinity of the relay connector.

It is a schematic block diagram of the hot water supply apparatus which concerns on the Example of this invention. It is a front view of a hot water supply apparatus. It is a longitudinal cross-sectional view of a hot water supply apparatus. It is a perspective view of an atmospheric temperature detection means and a relay connector. It is a perspective view of another relay connector different from the atmospheric temperature detection means. It is a flowchart which shows the combustion control of a combustion apparatus.

  Hereinafter, modes for carrying out the present invention will be described based on examples.

Initially, the whole structure of the hot water supply apparatus 1 provided with the combustion apparatus of this invention is demonstrated.
As shown in FIG. 1, a hot water supply device 1 is composed of a combustion device 2 and a heat exchanger unit 3, and heat of combustion gas generated by burning fuel gas in the combustion device 2 is used in the heat exchanger unit 3. Hot water is used for heating.

  In the combustion apparatus 2, a burner portion 5 that burns fuel gas is accommodated inside a box-shaped burner can body 12 whose upper surface is open so that combustion gas can be supplied upward, and at the lower end portion of the burner can body 12. A blower fan 4 for supplying combustion air to the burner unit 5 is provided.

The heat exchanger section 3 is provided between the combustion gas supplied from the burner section 5 and water inside a box-shaped heat exchanger can body 6 whose bottom surface is open so that the combustion gas from the combustion device 2 can be introduced. Heat exchanger 8 (sensible heat recovery heat exchanger 8a, latent heat recovery heat exchanger 8b) is provided, and the combustion gas after heat exchange by the heat exchanger 8 is discharged from the heat exchanger can 6 Various exhaust pipes such as an exhaust port 9 for supplying clean water to the heat exchanger 8, a hot water pipe 10 b for discharging hot water heated by the heat exchanger 8, a temperature sensor for detecting the temperature of hot water, etc. A hot water flow sensor or the like (not shown) is provided.

The hot water supply device 1 also includes a control unit 7 (control means) that receives signals from various sensors and the like provided in the combustion device 2 and the heat exchanger unit 3 and drives and controls various devices.

Next, the burner unit 5 will be described.
The burner unit 5 includes a burner unit 11 that burns by mixing fuel gas supplied from a fuel supply pipe (not shown) and combustion air supplied from the blower fan 4, and a burner can body containing the burner unit 11. 12 and a combustion space 13 above the burner unit 10 in the burner can body 12.

  As shown in FIGS. 1 to 3, the burner unit 11 includes a plurality of combustion pipes 14 extending in the front-rear direction and arranged in the left-right direction. Each of the combustion stages 11a to 11c includes, for example, five, two, and three combustion pipes 14, respectively, and is connected to a corresponding fuel supply pipe. Each of the combustion stages 11a to 11c can be controlled by the control unit 7, and the number of combustion stages 11a to 11c and the output thereof are adjusted according to the hot water supply temperature or the like.

  At the time of combustion operation, for example, according to the hot water supply temperature or the like, for example, a first stage combustion stage in which only two combustion pipes 14 in the center combustion stage 11b are operated to burn, and five combustion pipes 14 in the center and right combustion stages 11b and 11c. A two-stage combustion stage in which the combustion operation is performed, a three-stage combustion stage in which the seven combustion pipes 14 in the left and center combustion stages 11a and 11b are combusted, and ten combustion pipes 14 in all the combustion stages 11a to 11c are combusted. The combustion operation is possible by switching the combustion stage to four stages of the four-stage combustion stage to be operated. The central combustion stage 11b corresponds to a combustion section that is always combusted during the combustion operation.

  As shown in FIG. 2, an igniter 15, a burner sensor 17, and a frame rod 16 are attached from the front side of the burner can body 12 in order from the left to the front portion of the burner can body 12 corresponding to the upper side of the combustion stage 11 b. Yes. As shown in FIG. 3, an igniter 15, a burner sensor 17, and a frame rod 16 protrude into the combustion space 13.

  The igniter 15 ignites the fuel-air mixture supplied from the burner unit 11 by generating an ignition spark with an ignition target provided in the burner unit 11, and projects into the combustion space 13. And it is attached so that it may extend toward diagonally downward.

  The flame rod 16 applies a voltage to the flame during the combustion operation of the burner unit 11, and detects the current flowing from the flame rod 16 to the flame by using the conductivity and rectifying action due to the ionization of the flame. It is attached to extend substantially horizontally so as to protrude into the combustion space 13.

  As shown in FIGS. 2 and 3, the burner sensor 17 corresponds to flame temperature detecting means for detecting the flame temperature of the burner unit 11 during combustion operation, and is attached to extend substantially horizontally so as to protrude into the combustion space 13. ing. The burner sensor 17 is composed of a thermocouple 17a and a pair of temperature compensating conductors 17b extending from the thermocouple 17a. A pair of temperature compensating conductors 17b are connected to the control unit 7 by a signal line 19 made of a copper wire or the like via a relay connector 18. The control unit 7 receives a detection signal of the burner sensor 17 and receives a flame temperature of the burner unit 11. To get.

Next, the thermistor 20 will be described.
The thermistor 20 corresponds to an atmospheric temperature detecting means, and when an atmospheric temperature at which there is a possibility that water in the piping of the heat exchanger 8 or the like may freeze when the combustion operation is not performed is detected, freezing prevention such as operation of an antifreezing heater is performed. Control is performed. Further, in order to use the thermistor 20 as a reference contact compensation means for the burner sensor 17 in the combustion control described later, as shown in FIG. 2, FIG. And connected to the control unit 7 by a signal line 20b so that the control unit 7 can acquire the detected ambient temperature.

  As shown in FIG. 4, the signal line 20 b of the thermistor 20 is bound by a signal line 19 that connects the relay connector 18 and the control unit 7 and a binding tool 21, and the temperature detection unit 20 a of the thermistor 20 is connected to the relay connector 18. Located in the vicinity. You may bind with an adhesive tape etc. instead of the binding tool 21.

Further, as shown in FIG. 5, the thermistor 20 may be disposed in the vicinity of the relay connector 18 via the fixing bracket 22. The fixing bracket 22 has an engagement hole 22 a on the front surface, and an engagement portion 22 b that holds the signal line 20 b of the thermistor 20 is inserted into the engagement hole 22 a so that the thermistor 20 is fixed to the fixing bracket 22. Is engaged with the side groove 18 a of the relay connector 18, so that the temperature detection unit 20 a of the thermistor 20 is disposed in the vicinity of the relay connector 18. Although not shown, the thermistor 20 may be fixed to the relay connector 18 with an adhesive tape, an adhesive, or the like.

Next, the control unit 7 will be described.
The control unit 7 shown in FIGS. 1 and 2 controls the hot water supply device 1 and corresponds to the control means of the combustion device 2, and various sensors are electrically connected to receive detection signals from these sensors. Is configured to do. The control unit 7 controls the blower fan 4, the burner unit 11, and the like based on the hot water supply temperature and the hot water supply amount set at the time of combustion operation, detection signals received from various sensors, and the like. Further, when the thermistor 20 detects an atmospheric temperature at which there is a risk of pipe freezing when the combustion operation is not performed, anti-freezing control such as operation of the anti-freezing heater is performed.

Next, combustion control using the thermistor 20 by the control unit 7 as the reference contact compensation means will be described with reference to FIG. In the figure, reference sign Si (i = 1, 2,...) Represents each step.

When the opening of the hot-water tap is detected, the combustion device 2 starts the combustion operation. When the combustion operation starts, the fan correction number N is set to the initial value “0” (S1), the flame detection temperature T1 detected by the burner sensor 17 is acquired (S2), and the relay connector detected by the thermistor 20 The detected temperature T2 of the atmosphere in the vicinity of 18 is acquired (S3). Each time the fan correction number N increases, the number of rotations of the blower fan 4 is increased by a preset number of rotations, and when the number of fan corrections decreases, the number of rotations of the blower fan 4 is decreased by a predetermined number of rotations. It is an index to make it.

Next, the combustion control use temperature T that is the corrected flame temperature is calculated as T = T1 + T2 from the detected temperature T1 and the detected temperature T2 acquired in S1 and S2 (S4).

Next, it is determined whether or not the combustion control use temperature T continues at a temperature equal to or higher than the fan rotation speed increase determination temperature Tup, which is a determination criterion for increasing the rotation speed of the blower fan 4 (S5).

When the determination in S5 is Yes, it is determined whether the fan correction number N is a predetermined fan correction number upper limit Nmax, for example, whether N is “8” (S6). If the determination in S6 is Yes, the process proceeds to S8 without changing the rotational speed of the blower fan 4. If the determination in S6 is No, the fan correction number N is increased by 1, and the rotational speed of the blower fan 4 is set to the current rotational speed. To a predetermined number of revolutions, for example, the number of revolutions corresponding to 2% of the initial number of revolutions of the blower fan 4 (S7), and the process proceeds to S8. The initial rotational speed of the blower fan 4 is set in advance according to the number of combustion stages.

In S8, it is determined whether or not the combustion control use temperature T continues at a temperature equal to or higher than a safe combustion enable / disable determination temperature Tcut that is an upper limit temperature at which it is determined that the combustion operation can be safely performed for 60 seconds. If the determination is Yes, a safety operation such as stopping combustion is executed (S9), and the combustion control is terminated. If No, the process returns to S2.

On the other hand, when the determination in S5 is No, it is determined whether or not the combustion control use temperature T is lower than the fan rotation speed decrease determination temperature Tdown that is a determination criterion for decreasing the rotation speed of the blower fan 4 (S10).

If the determination in S10 is No, the process returns to S2, and if Yes, it is determined whether the fan correction number N of the blower fan 4 is the lower limit “0” (S11). If the determination in S11 is Yes, the process returns to S2 without changing the rotational speed of the blower fan 4, and if No, the fan correction number N is decreased by 1, and the rotational speed of the blower fan 4 is determined from the current rotational speed. Is reduced by, for example, a rotational speed corresponding to 2% of the initial rotational speed (S12), and the process returns to S2.

As in the combustion control described above, the control unit 7 controls the rotational speed of the blower fan based on the combustion control use temperature T, which is the corrected flame temperature, and adjusts the combustion state of the combustion device 2.

Next, the operation and effect of the combustion apparatus 2 of the present invention will be described.
In the combustion apparatus 2 of the present invention, the thermistor 20 that is the atmospheric temperature detection means used for the freeze prevention control or the like is also used as the reference contact compensation means of the burner sensor 17 that is the flame temperature detection means at the time of combustion control. The flame temperature detected by the burner sensor 17 can be corrected to accurately acquire the flame temperature burned by the burner unit 11, and the blower 4 is controlled by the corrected flame temperature to adjust the combustion state. be able to. Further, the thermistor 20 is provided for preventing the pipe from freezing, and the reference contact compensation means can be easily provided at a low cost without adding any special equipment.

  Further, since the thermistor 20 and the burner sensor 17 are separately connected to the control unit 7, when one is replaced, the other is not replaced together, and can be replaced separately.

  Furthermore, since the signal line 19 connecting the relay connector 18 and the control unit 7 and the signal line 20b of the thermistor 20 are bundled, the thermistor 20 can be easily arranged in the vicinity of the relay connector 18.

  Further, since the thermistor 20 is fixed to the relay connector 18 via the fixing bracket 22, the thermistor 20 can be easily disposed in the vicinity of the relay connector 18.

  Those skilled in the art can implement the present invention in various forms with various modifications without departing from the spirit of the present invention, and the present invention includes such modifications.

DESCRIPTION OF SYMBOLS 1 Hot-water supply apparatus 2 Combustion apparatus 3 Heat exchanger part 4 Blower fan 5 Burner part 6 Heat exchanger can body 7 Control unit (control means)
8 Heat Exchanger 8a Sensible Heat Recovery Heat Exchanger 8b Latent Heat Recovery Heat Exchanger 9 Exhaust Port 10a Inlet Pipe 10b Outlet Pipe 11 Burner Unit 11b Combustion Unit 12 Burner Can 13 Combustion Space 14 Combustion Pipe 15 Igniter 16 Frame Rod 17 Burner sensor (flame temperature detection means)
17a Thermocouple 17b Temperature compensation lead wire 18 Relay connector 18a Side groove 19 Signal wire 20 Thermistor (atmosphere temperature detection means)
20a Temperature detection part 20b Signal line 21 Binding tool 22 Fixing bracket 22a Engagement hole 22b Engagement part

Claims (2)

A combustion section, a flame temperature detection means for detecting a flame temperature generated in the combustion section, an atmosphere temperature detection means for detecting the temperature of the atmosphere, and a control means for controlling the combustion state based on the detected flame temperature A combustion device,
The flame temperature detecting means is connected from the flame temperature detecting means to the relay connector with a temperature compensating conductor, and from the relay connector to the control means is connected with a signal line,
The ambient temperature detection means is arranged in the vicinity of the relay connector by being bundled with a signal line from the control means to the relay connector in order to serve as a reference contact compensation means of the flame temperature detection means,
The said control means correct | amends the flame temperature detected by the said flame temperature detection means with the atmospheric temperature detected by the said atmospheric temperature detection means, The combustion apparatus characterized by the above-mentioned. The combustion apparatus according to claim 1, wherein the ambient temperature detection unit is fixed to the relay connector via a fixing bracket .