JPS58106358A - Boiler - Google Patents

Abstract

PURPOSE:To supply a heat-transmitting medium easily and safely, by a method wherein a detecting electrode and a detecting circuit for a heat-transmitting medium are provided in each of a shell body and an auxiliary tank, in a boiler provided with a shell body and an auxiliary tank for replenishing a heat-transmitting medium when the amount of the medium in the shell body is reduced due to evaporation or the like. CONSTITUTION:In a boiler, the heat-transmitting medium in a shell body 1 is heated by a burner 3, and the medium thus heated is fed into a hot water type heat exchanger or the like by a circulating pump 4. When the amount of the medium in the shell body 1 is reduced, the medium in the auxiliary tank 2 is sucked into the shell body 1 by a pressure difference generated between the shell body 1 and the tank 2. In this case, the electrodes 5, 6 for detecting the medium in the shell body 1 and the tank 2 are provided. In replenishing the medium, when the level of the medium in the tank 2 is lowered to or below a set level of the electrode 6, operations of the pump 4 and the burner 3 are stopped, and the tank 2 is replenished with the medium. When the amount of the medium in the shell body 1 is reduced to or below a set level of the electrode 5, the condition is recognized as a breakage of the shell body or the like, and the operations are similarly stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a boiler having an auxiliary tank for replenishment when the amount of heat medium in the can decreases, and particularly relates to the detection of the heat medium. The purpose of this system is to provide a circuit to improve the safety of the boiler and to facilitate the replenishment of heat medium.

In conventional hot water boilers of this kind, the method for detecting the heating medium was to provide a detector in either the can body or the auxiliary tank. In such a case, first of all, with the method of installing a detector in the can body, the heating medium will decrease, and if you forget to replenish the auxiliary tank, the heating medium in the auxiliary tank will completely run out. However, the operation continues and will not stop unless the heat medium inside the can decreases. At that point, air is trapped in the heating circuit, making replenishment extremely difficult. Furthermore, the method of installing a detector in the auxiliary tank is extremely dangerous because if the detector malfunctions and the heat medium decreases, the tank will become empty. Furthermore, if the heating medium inside the can suddenly decreases due to an accident such as damage to the can, there is also the problem that the heating becomes dry.

The present invention was made in order to solve these conventional problems, and the can body and the auxiliary tank are each provided with a detector, and the detector provided in the auxiliary tank prompts the replenishment of the heat medium. In the event of a detector malfunction or damage to the can, the detector installed inside the can will stop the operation. One embodiment will be described below with reference to the drawings.

Figure 1 is a diagram showing the structure of the main body. 1 is a can body, 2 is an auxiliary tank 3 for replenishing the heating medium in the can body 1 when it decreases, and 4 is a burner for warming the heating medium in the can body 1. is a circulation pump for conveying the heat medium to a hot water heat exchanger, etc., M is a hot water bamboo pipe, and B is a hot water return pipe. Reference numeral 5 indicates an electrode for detecting the heat medium within the can body 1, and reference numeral 6 indicates an electrode for detecting the heat medium within the auxiliary tank 2. With the above configuration, when the heat medium in the can body 1 decreases, replenishment from the auxiliary tank 6 to the auxiliary tank 2 is possible.
A pressure difference occurs between the two, which causes suction into the can body 1,
This means that it will be replenished. Figure 2 shows the load circuit, where 7 is a commercial power supply, 8 is an operation switch, 9 is a power transformer for the control circuit,
1o is the vaporization heater of burner 3, 11 to 15 are the contacts of the load control relay, 16 is the burner motor of burner 3, 1
7 is a pulse pump for supplying fuel to the third burner section, and 18 is an igniter for the third burner section. Figure 3 shows a control circuit, 19 is a DC power supply for the control circuit, 2o is a vaporization heater control circuit, 21
22 is a pre-purge circuit for burner 3, 23 is an igniter drive circuit, and 24 to 27 are the above-mentioned 20 to 23.
28 to 3o are resistors, 31 is a capacitor, 32 is an operational amplifier, 33 is a relay, 34 is a transistor, and 28 to 34 form a circulation pump drive circuit. There is. 35 is a combustion detection circuit for burner 3, 36 is a flame rod, 37 is a resistor, 38 is a capacitor, 39 to 42 are resistors, 43 is a PLTT, and 44 is a transistor. It forms a heat medium detection circuit. 45-48 are resistances, 49
is a PUT, 5o is a transistor, 51.52 is a diode, the above 45 to 6 degrees and 6 form a heat medium detection circuit in the auxiliary tank 2, and the outputs of the transistors 44 and 50 are connected to an operational amplifier 32 in a ND configuration. It is connected to the power of ten people. Also, the output of the operational amplifier 32 and the input of the hot water temperature thermo circuit 21 are connected via the diode 62, and when the circulation pump drive circuit is stopped, the hot water temperature thermo circuit 21 is set to the oyy state, and the burner 3 to stop.

To explain the operation of the above configuration, first, when the operation switch 8 shown in FIG. o'- via power supply 19;

Then, power is supplied to the control circuit. As a result, the output of the vaporization heater control circuit 2o becomes 0il, the relay 24 is energized, the contact 11 shown in FIG. 2 is closed, and the vaporization heater 10 starts heating. At the same time, since the can body 1 and the auxiliary tank 2 are sufficiently filled with a heating medium, a current flows between the polarizations 5 and 6 through the heating medium. This allows PU743 and 49
becomes conductive, and transistors 44 and 60 become OFF. That is, the capacitor 31 is charged through the resistor 28, and when the potential becomes higher than the potential determined by the resistors 29 and 30, the output of the operational amplifier 32 becomes 1 state, the transistor 34 is turned on, the relay 33 is energized, and the contact 12 is closed. Therefore, the circulation pump 4 is driven.

Next, the heating of the vaporization heater 1o progresses, and when the predetermined temperature is reached, the stop signal to the hot water temperature thermocircuit 21 is released, and the subsequent combustion control circuit starts operating.

First, by turning on the output of the hot water temperature thermo circuit 21, the relay 2
6 is energized, the contact 13 is closed, the burner motor 16 is driven, and then the blipurge circuit 22 is turned on after a predetermined period of time has elapsed.
As a result, the relay 26 is energized. At the same time, the igniter drive circuit 23 is turned on and the relay 27 is energized. As a result, the contacts 14 and 16 are closed, the pulse pump 17 and the igniter 18 are driven, and the pulp pump 17 supplies liquid fuel to the burner 3 section, which is vaporized by the vaporization heater 1o. are mixed and ignited. When ignited, the combustion detection circuit 36 activates the igniter drive circuit 23 via the flame rod 36, de-energizes the OFF relay 27, opens the contact 16, stops the operation of the igniter 18, and shifts to normal combustion.

Next, when the heat medium in the can body 1 decreases in this state, a pressure difference occurs between the can body 1 and the auxiliary tank 2, as described above, which causes the heat medium in the auxiliary tank 2 to decrease. However, as the replenishment progresses and the level of the heat medium falls below the installation level of the electrodes 6, the space between the electrodes 6 becomes open.
Since the gate of PUT49 is set to high level, PUT
49 becomes non-conductive, and the transistor 60 becomes the resistor 46.
, 47, so that they are in a conductive state. When the transistor 50 turns on, the capacitor 3
The charge of 1 is discharged through the transistor 6o.

That is, the ten inputs of the operational amplifier 32 go to the Low state, and the output also goes to the Low state. As a result, the transistor 34 is turned off, the relay 33 is de-energized, the contacts 12 are opened, and the circulation pump 4 and burner motor 16. The pulse pump 17 is stopped and the fire is extinguished. At the same time, the control circuit side also turns off the hot water temperature thermo circuit 21 via the diode 62.
It is kept in F state. If the auxiliary tank 2 is replenished here, it will automatically return and restart.

Next, if the heat medium detection circuit of auxiliary tank 2 fails,
The operation when the can body 1 is damaged will be explained. In this case, when the heat medium decreases to below the installation level of the electrode 6 provided in the can body 1, the gap between the electrodes 5 and 6 becomes open, so the gate of the PUT 43 is set to a high level as described above. Therefore, it becomes non-conductive and the transistor 44 is turned on. This causes the ten inputs of the operational amplifier 32 to become Low, l! =7!
11 output becomes Low and transistor 34 turns off.
, Relay -33 is de-energized, contact 12 is opened, and the circulation cylinder is opened? yf open 8#58-1υ6; J58 (drip 4 and stops combustion.Here, if the power source of the heating medium detection circuit is DC, an oxide film is generated due to polarization.
AC power is used because there are problems such as electrodes melting.

As described above, according to the present invention, when the heat medium decreases,
It stops the operation before air is trapped in the heating piping, prompts replenishment, and requires replenishment only to the auxiliary tank, making the replenishment operation easy. In addition, if the detection circuit on the auxiliary tank side malfunctions or the can body is damaged, the detection circuit on the can side will detect it, so there will be no dry firing, improving safety. It is something.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing one embodiment of the present invention, Fig. 2, Fig. 3
The figure is the same circuit diagram. 1... Can body, 2... Auxiliary tank, 3.
...Burner, 4...Circulation pump, 5,6
......electrode, 32...mountain, operational amplifier. Name of agent: Patent attorney Satoshi Nakatashi (T1 or 1 person) Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A can body and an auxiliary tank for replenishing when the heat medium in the can body decreases due to evaporation etc., each of the can body and the auxiliary tank is provided with a heat medium detection electrode and a detection circuit, and each detection circuit Boiler whose output is connected to the input of the circulation pump drive circuit.