JPS6247006Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a combustion device that is equipped with two or more heating combustors that can be used independently for hot water supply and space heating, such as a hot water heater, and the exhaust gas from these combustors is shared. This invention relates to a forced combustion device in which exhaust gas is discharged to the outside through an exhaust stack by a common blower.

Conventionally, in this type of device, each combustor is ignited after a certain pre-purge time delay from the start of operation of the blower in response to an ignition signal from a temperature control circuit that operates by detecting the temperature of the respective heated object. Generally, each combustor is equipped with a delay circuit, but according to this, if an ignition signal is generated from the temperature control circuit of another combustor during the combustion operation of any one combustor, the Even though the blower operates and there is no need for pre-purging, the delay circuit causes a delay in ignition, and during this delay time the temperature of the heated object drops significantly from the set temperature due to the cold air flowing through the other combustor. However, this results in the disadvantage that the range of temperature change of the object to be heated becomes large.

The purpose of the present invention is to provide a device that eliminates such inconveniences, in which a plurality of heating combustors 1 are arranged in parallel so that they can be used independently, and the exhaust gas from each heating combustor 1 is discharged to the outside. A common exhaust stack 2 equipped with a blower 3 for discharging air is provided, and each heating combustor 1 is provided with a temperature control circuit 4 that operates by detecting the temperature of the heated object, and the blower 3 is connected to which temperature control circuit. In addition, each heating combustor 1 is operated by an ignition signal from each temperature control circuit 4, and there is a delay of a certain pre-purge time from the start of operation of the blower 3 by the ignition signal from each temperature control circuit 4. In a device that is ignited, a common 1 inputs signals from these temperature control circuits 4 and outputs an activation signal after the pre-purge time has elapsed depending on the ignition signal from any temperature control circuit 4.
A delay circuit 5 is provided, and each temperature control circuit 5 receives a signal from the delay circuit 5 and a signal from each temperature control circuit 4.
AND circuits 25A, 25B, 25C... are provided, and the corresponding heating combustor 1 is ignited by the output from the AND circuit into which the activation signal from the delay circuit 5 and the ignition signal from the temperature control circuit 4 are input. is characterized in that it is given.

In the illustrated example, three heating combustors 1 are installed in parallel: an intermediate hot water supply combustor 1A, a heating combustor 1B on the left, and a bath heater combustor 1C on the right. and the heat exchanger 7 above it
A hot water supply pipe 10 leading from the hot water supply combustor 1A to the shower 8 and the hot water tap 9, and a heating combustor 1
A heating pipe line 13 with a pump 11 and an indoor heating radiator 12 interposed from B, and a bath heater combustor 1C
Heater pipes 16 with a pump 14 and a bath heater radiator 15 interposed therein are led out, and thermistors and other temperature sensing elements 17A, 17B, 17C are arranged in each of these pipes 10, 13, 16, respectively. Each temperature control circuit 4 of each combustor 1A, 1B, 1C according to the detected temperature of each temperature sensing element 17A, 17B, 17C.
A, 4B, and 4C are activated, and a high level ignition signal is generated when the detected temperature falls to the lower limit set temperature, and a low level extinguishing signal is generated when the detected temperature rises to the upper limit set temperature. The delay circuit 5 is configured, for example, as shown in FIG.
A transistor 18 in which the output terminals from A, 4B, and 4C are commonly connected to the base terminal, and a wind pressure switch 2 that is linked to a wind pressure detection device 19 provided in the exhaust stack 2.
0 in series, and a first comparator 22 that receives the potential from the voltage divider circuit 21 as input.
, an electrolytic capacitor 23 on the output side of the first comparator 22, and a second capacitor 23 to which the potential of the capacitor 23 is input.
When a high-level ignition signal is generated from any one of the temperature control circuits 4A, 4B, and 4C, the transistor 18 is made conductive, and the blower 3 is activated by the ignition signal. The wind pressure switch 20 is closed, and a high level output is generated from the first comparator 22 due to the input potential from the voltage dividing circuit 21, which charges the electrolytic capacitor 23 and the pre-purge time whose potential is constant elapses. Later, when a predetermined high potential is reached, the second comparator 24
A high-level activation signal is now generated.

Then, the output terminal of the delay circuit 5 derived from the output side of the second comparator 24 is connected to each temperature control circuit 4.
Each AND connecting the output terminals of A, 4B, and 4C
Connect to circuits 25A, 25B, 25C, and
Each relay that will be energized by the upcoming high level output on the output side of AND circuits 25A, 25B, and 25C
RA, RB, RC are provided, and according to the energization, each combustion control circuit 26A, 2 of each combustor 1A, 1B, 1C
Each relay contact rA connected in series to 6B and 26C,
rB and rC are closed, and each combustor 1A, 1B, 1
C ignition is now provided. In addition, blower 3
When the amount of exhaust gas is small, such as when the heating combustor 1B or the bath heater combustor 1C is in independent combustion operation, the operation is switched to deceleration mode by a known means.In this case, the wind pressure switch 20 is opened due to insufficient wind pressure. Therefore, a second electrolytic capacitor 28 is provided to charge the output from the first comparator 22 via a resistor 27, and the potential of the capacitor 28 is inputted to the first comparator 22 to calculate the wind pressure. switch 20
Even when the first comparator 22 is opened, a high level output is continuously generated from the first comparator 22.

Next, to explain the overall operation of the present device, when all the combustors 1A, 1B, and 1C are in the extinguished state and the operation of the blower 3 is stopped, any temperature control circuit, for example, a temperature control circuit for hot water supply, is activated. 4A
When an ignition signal is generated, first the blower 3 starts operating, and an activation signal is generated from the delay circuit 5 after a certain pre-purge time has elapsed, and the output of the hot water supply AND circuit 25A becomes high level. The hot water supply combustor 1A is ignited.

In this state, if an ignition signal is generated from another temperature control circuit 4B for heating, for example, since an activation signal has already been generated from the delay circuit 5,
A high level output is immediately generated from the circuit 25B, and the heating combustor 1B is ignited without any delay time.

FIG. 3 shows the hot water supply temperature control circuit 4A of the hot water supply combustor 1A in a state in which the heating combustor 1B is in continuous combustion operation, that is, in a state in which the ignition signal is continuously generated from the heating temperature control circuit 4B. FIG. 3 is a diagram showing the change in outlet temperature when combustion control is performed, in which the a line shows the change characteristic of the device of the present invention, and the b line shows the change characteristic of the conventional device.

As is clear from the figure, according to the device of the present invention, an activation signal has already been generated from the common delay circuit 5 in response to an ignition signal from the heating temperature control circuit 4B, so that the hot water temperature does not reach the lower limit set temperature _T1 . When the ignition signal is generated from the hot water temperature control circuit 4A during the descent, the hot water combustor 1A is immediately ignited, and the upper limit set temperature is reached.
When the temperature rises to _T2 , the combustor 1A is extinguished by the extinguishing signal generated from the temperature control circuit 4A, and the outlet hot water temperature is kept within the upper and lower set temperature ranges.

On the other hand, according to conventional equipment, the lower limit set temperature
Even if an ignition signal is generated due to the drop to T ₁ , the ignition of the hot water supply combustor will be delayed due to the delay circuit installed separately for each combustor, and by the time it is ignited, the outlet temperature will be much higher than the lower limit set temperature T ₁ . According to this, the intermittent combustion time until the hot water temperature after ignition reaches the upper limit set temperature T ₂ and the fire is extinguished becomes longer, and the range of rise in the hot water temperature after the fire is extinguished due to residual heat increases accordingly, and the hot water temperature decreases. begins to show wide fluctuations.

As described above, according to the present invention, the delay circuit 5 is used in common, and while any one heating combustor 1 is in combustion operation, the other heating combustor 1 is immediately ignited by the ignition signal from the temperature control circuit 4. This has the effect that the temperature of the object to be heated does not drop during the ignition delay time, and the range of temperature change can be controlled as narrowly as possible.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of one example of the device of the present invention, FIG. 2 is an electric circuit diagram thereof, and FIG. 3 is a comparative characteristic diagram of the device of the present invention and a conventional device. 1...Heating combustor, 2...Exhaust stack, 3...Blower, 4...Temperature control circuit, 5...Delay circuit, 25A,
25B, 25C...AND circuit.

Claims (1)

[Scope of utility model registration request] A plurality of heating combustors 1 are arranged in parallel so that they can be used independently, and a common exhaust pipe 2 equipped with a blower 3 for discharging exhaust gas from each heating combustor 1 to the outside is provided. A temperature control circuit 4 that detects the temperature of the object to be heated and operates is provided in the temperature control circuit 4, and the blower 3 is operated by an ignition signal from any temperature control circuit 4, and each heating combustor 1 is designed to be ignited with a certain pre-purge time delay from the start of operation of the blower 3 by the ignition signal from each temperature control circuit 4, and when the signals from these temperature control circuits 4 are input, A common delay circuit 5 is provided which outputs an activation signal after the pre-purge time has elapsed even in response to the ignition signal from the temperature control circuit 4, and further inputs the signal from the delay circuit 5 and the signal from each temperature control circuit 4. Each AND circuit 25A, 25B, 25C
... is provided, and the corresponding heating combustor 1 is ignited by the output from the AND circuit into which the activation signal from the delay circuit 5 and the ignition signal from the temperature control circuit 4 are input. A forced combustion device featuring: