JPS6016847Y2 - Gas equipment operation control device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an operation control device for gas appliances, and particularly to an operation control device for gas hot air heaters and the like.

FIG. 1 is a diagram of a gas combustion system of a conventional FF type gas hot air heater, which is the background of this invention and to which this invention can be applied.

The gas sent to the gas pipe GP by opening the gas cock is
As shown by the arrow, the main gas valve (main gas solenoid valve)
MV and pilot gas valve (pilot gas solenoid valve) PV
The gas is fed into the heat exchanger HEX as a gas combustion section.

The pilot gas that passes through the pilot gas valve PV is ignited within this heat exchanger HEX to serve as a pilot flame, and ignites the main gas that passes through the main gas valve MV.

These pilot flame and main flame are forcibly sent into the heat exchanger HEX from the intake port INT by a combustion fan (not shown) that is rotationally driven according to the energization of the combustion fan motor BM. Sustain combustion with air.

Further, carbon dioxide gas and soot generated within the heat exchanger HEX are discharged to the outside through the exhaust port EXH.

Heat exchanger HE heated by ignited and combustible main input
The heat of X is radiated into the room by a hot air fan HF that is rotationally driven by a fan motor FM.

Therefore, the room can be heated without contaminating the air.

Further, the main gas valve station is opened after confirming that the pilot flame is ignited by a pilot flame detector FX including, for example, a thermocouple and a relay.

FIG. 2 is an electrical circuit diagram of the control device of FIG. 1 as an interesting prior art to this invention.

Hereinafter, the configuration and operation will be explained with reference to FIGS. 1 and 2.

First, when the power switch PS is closed, the power supply AC100
AC power from V is given to the combustion fan motor BM via a current fuse CF, a temperature fuse THF, and a closed power switch circle.

The combustion fan therefore starts rotating and delivers combustion air into the heat exchanger HEX.

Next, when the ignition switch IGS is closed, electric power from the power supply is applied to the pilot gas valve PV via the closed ignition switch IGS, and this valve PV is opened.

Therefore, a small amount of pilot gas is fed from the gas pipe PG into the heat exchanger HEX as a gas combustion section.

At this time, the pilot flame has not been ignited yet, so the relay switch FXI included in the pilot flame detector FX is connected to the contact FX l.
l) and FXlc are electrically connected, and relay switch Fx2
The contacts Fx2a and Fx2C are open (blocked).

Therefore, the igniter IGN is energized to ignite the pilot gas via the pilot gas valve PV.

When the pilot flame is lit, the pilot flame detector FX detects the pilot flame.

Therefore, the relay switch F included in the pilot flame detector FX
Contacts FX1a and FXlc of Xl are electrically connected, and contacts FX2a and FX2c of relay switch FX2 are electrically electrically connected.

Further, the indoor temperature thermostat RTS is closed because the indoor temperature is lower than a predetermined constant value (set value).

Therefore, AC power from the power source ACIQQV is applied to the main gas valve MV, and this valve W is opened.

Therefore, the main gas is fed into the heat exchanger HEX via this main gas valve W, and is ignited by the ignited pilot flame.

As mentioned above, when the main input is ignited and reaches a temperature at which the heat exchanger HEX is heated, the delay thermostat (DTH) is closed.

Therefore, electric power from the power supply is applied to the warm air fan motor FM, energizing it.

Therefore, this hot air fan FM starts rotating,
The room is heated by heated air from the heat exchanger HEX.

In addition, the delay thermostat DTH prevents cold air from blowing out immediately after the start of main combustion, and even after the operation is stopped, the heat exchanger HE
This is to blow out warm air while the temperature of X is high.

Furthermore, the overheat prevention thermostat OHT and the temperature fuse THF are used to cut off the power and stop the operation of the equipment when the temperature of the equipment rises abnormally.

When the room is heated by hot air and its temperature becomes higher than the set value, the room temperature thermostat RT
S is opened (blocked).

Therefore, the main gas valve MV is closed and the gas supply through this valve MV is stopped.

In this way, the indoor temperature can be kept approximately constant.

In conventional gas hot air heaters as described above, even after the indoor temperature rises above the set value, the indoor temperature thermostat is opened (the main gas valve is closed), and the main gas is extinguished, the combustion fan continues to operate. Since the engine continues to rotate, that is, cold combustion air from outside is sent into the heat exchanger, the heated heat exchanger is cooled down.

Therefore, the indoor temperature will drop rapidly, which is not preferable from the viewpoint of energy saving.

Therefore, it is conceivable to stop the delivery of combustion air as soon as the main input is extinguished when the temperature related to the gas combustion section is above a preset value.

However, even if the delivery of combustion air is stopped after the main inlet is extinguished, the heat exchanger HE
X may be filled with gas.

In such a case, if the temperature associated with the gas combustion part falls below a predetermined set value and the main air is ignited at the same time as combustion air is created, there may be a risk of explosion or the like.

In such a case, if a delay means is provided in the control means for igniting the main input, and the main input is ignited after a certain period of time has elapsed after creating combustion air, risks such as explosion can be avoided.

However, the above function alone is not necessarily safe in cases where the igniter does not ignite even after a certain period of time has elapsed, such as when the igniter breaks down, and countermeasures for such cases are required.

Therefore, the main purpose of this invention is to operate gas appliances that can operate safely even when the ignition means does not operate after a certain period of time, when gas supply is temporarily stopped, or when a temporary power outage occurs. The purpose of the present invention is to provide a control device.

In summary, this invention is based on the fact that in response to the temperature detection means detecting a temperature below a predetermined set value, the ignition means is controlled after a predetermined period of time has elapsed, and the pilot flame is ignited. , is an operation control device for gas appliances that has a function of stopping all energization and closing gas valves and others if the pilot flame does not ignite after the predetermined period of time has elapsed.

FIG. 3 is an electrical circuit diagram of an embodiment of this invention.

The configuration and operation will be explained below with reference to FIGS. 1 and 4.

When the power switch circle is closed (on), the power supply AC100
The AC power from V is the current fuse CF.

Thermal fuse THF is applied to the self-holding relay via the closed power switch PS to energize the relay.

Therefore, relay contact AXa is closed and this relay AX
is self-retained and continues to be energized even after the power switch circle is opened.

When , the indoor temperature is below the set value (of the indoor temperature thermostat RTS), so the indoor temperature thermostat RT
S remains closed.

Therefore, the combustion fan motor BM is energized.

On the other hand, the heat exchanger HEX also remains cold, and the hot air thermostat HAT is opened.

Therefore, the hot air fan motor FM remains deenergized.

When the combustion fan motor BM is energized, a combustion fan (not shown) starts rotating accordingly, and combustion air is sent into the heat exchanger HEX from the intake port INT.

Therefore, the wind pressure switch WPS disposed within the heat exchanger HEX senses the wind pressure caused by the fan and is closed.

Therefore, power is applied to the pilot flame detector FX via the closed wind pressure switch WPS.

However, at this time, since the pilot flame is not lit, the relay switch FXl included in the pilot flame detector FX has its contacts FXll) and FXlc electrically connected, and the relay switch FX2 has its contacts FX2b and FX2C electrically connected. .

Therefore, the AC power is passed through the relay switch FXl and the delay circuit DLY to the igniter IGN, the heating resistor RH,
It is given to the parallel circuit of the pilot gas valve PV (relay switch FX2).

When alternating current is applied to the delay circuit DLY, the diode DI
, D2. D3. A DC voltage with a small ripple component that is rectified by the bridge circuit constituted by D4 and smoothed by the capacitor C2 is applied to both ends of the thyristor SCR.

At the same time, diode D2. The current (voltage) flowing through D4 is charged into capacitor C1 through resistors R1 and R2.

When the charging voltage of capacitor C1 exceeds the breakover voltage of silicon bidirectional switching element SBS, which has characteristics similar to SSS, for example, this switching element SB
S transitions to a conductive state.

Therefore, the charge in the capacitor C1 is applied to the gate electrode of the thyristor SCR via this switching element SBS.

Therefore, the thyristor SCR becomes conductive, and at the same time, the bridge circuit connecting the diodes D1 to D4 also becomes conductive.

In other words, the delay circuit DLY waits for a certain period of time (
In other words, conduction is delayed by the charging time of capacitor C1.

That is, the igniter IGN, the heating resistor RH, and the pilot gas valve PV are energized by the delay circuit DLY, and then energized after a certain period of time has elapsed.

When the delay circuit DLY becomes conductive as described above, the pilot gas valve PV is energized and opened, and the igniter IGN is energized.

Therefore, a small amount of pilot gas is fed into the heat exchanger HEX and ignited.

Therefore, the pilot flame detector FX detects that the pilot flame has been ignited, and accordingly, the relay switch FXl switches between the contacts FXla and F.
The waist relay switch FX2 is conductive with Xlc and the contact FX2a
and FX)c are electrically connected.

Therefore, the main gas valve MV is energized and opened,
The main input via this valve MV is the heat exchanger HEX.
The pilot flame is ignited by the ignited pilot flame to start combustion.

Note that if the pilot flame is not ignited even after a certain period of time has elapsed, the heating resistor RH continues to be energized, so that the resistor RH generates heat and reaches a certain temperature.

When the heating resistor RH reaches a certain temperature or higher, the associated heating thermostat RH3 is opened (turned off), the self-holding relay AX is deenergized, and the self-holding of this relay is released.

Therefore, no further control is performed.

As mentioned above, when the main input starts combustion, the heat exchanger HE
X is heated and the hot air thermostat)-HAT is closed.

Therefore, the warm air fan motor FM is energized, and the heat of the heat exchanger HEX is dissipated into the room by the hot air fan that is rotationally driven accordingly.

Therefore, the indoor temperature gradually rises and exceeds the set value.

When the indoor temperature reaches or exceeds the set value, the indoor temperature thermostat RTS is opened (turned off) and energization to subsequent circuits is stopped, so the combustion fan motor BM is deenergized and the delivery of combustion air is accordingly stopped. will be stopped.

Thereafter, when the room temperature falls below the set value, the thermostat RTS is closed and the above-described operation is repeated.

Furthermore, if gas supply is stopped for some reason during main combustion, gas supply starts again in a very short period of time, and then the gas is ignited again and combustion is restarted.

However, if the gas supply stop time is relatively long, the subsequent operation control is stopped by the action of the heat generating resistor RH.

Of course, in the event of a temporary power outage during operation, even if the power is turned on again, the operation remains stopped because the self-holding of relay AX has been released.

As mentioned above, according to this embodiment, specific effects as described below can be achieved.

(1) When the indoor temperature exceeds a predetermined set value (based on the indoor temperature thermostat) and gas combustion is stopped, the combustion fan is stopped accordingly and the delivery of combustion air is stopped. Therefore, the indoor temperature can be prevented from being cooled down rapidly, and gas can be saved.

Also, since the combustion fan (motor) stops, power can be saved.

(2) When the indoor temperature falls below a predetermined set value,
In order to prevent the ignition from happening immediately, a delay circuit is provided so that the combustion fan starts rotating and the air in the heat exchanger is sufficiently replaced before the igniter is activated (pre-purge), so the response of the pilot flame detector is Even if a delayed one is used, there is no risk of explosion and ignition, and it is safe to use.

(3) It is safe because it will not be re-ignited when the temporary power outage or gas supply is stopped for a relatively long time.

(4) If the igniter fails, for example, and the ignition does not start after a certain period of time, all gas valves are closed and power to the igniter is stopped, making it even safer.

FIG. 4 is an electrical circuit diagram of another embodiment of this invention.

This FIG. 4 is substantially the same as FIG. 3 except for the following.

That is, in Fig. 3, a heat generating resistor RH and a heat generating thermostat RH3 are used to detect that the ignition does not occur even after a certain period of time has elapsed after electricity is applied, but in Fig. 4, for example, a delay relay or a timer is used. The operation is now stopped according to the timing of a time limit means such as a constant timer.

In other words, when the delay circuit DLY is conductive, the igniter IGN,
The pilot gas valve Pv is energized and the pilot flame is ignited.

The timer relay TX starts timing after being energized, and when a predetermined time (no ignition) is counted, its contact TXb is opened.

Therefore, the self-holding of the relay is released, and the subsequent power supply to the circuit is stopped.

Further, since the other configurations and operations are the same as those shown in FIG. 3, their explanations will be omitted.

FIG. 5 is a gas combustion system diagram of a FF type gas hot air heater according to still another embodiment of this invention.

This FIG. 5 is substantially similar to FIG. 1 except as follows.

That is, the gas sent to the gas pipe GP by opening the gas cock is heated as the main gas through the all-gas valve (all-electromagnetic valve) AV and the main valve (top-heating solenoid valve) MV, as shown by the arrow. It is fed into the exchanger HEX, and is also fed into the heat exchanger HEX as pilot gas through the all-gas valve AV.

As described above, the feature of this embodiment is that the main supply and the pilot supply are combined into one system, and the supply thereof is intermittent by the all-gas valve AV.

In the control device shown in FIG. 5, if the pilot gas valve PV in FIGS. 3 and 4 is replaced with the all-gas valve AV, the operation control operation can be performed in the same manner.

In addition, in the above-mentioned Example, although the gas hot-air heater was demonstrated, this can of course be applied, for example to a gas hot water supply facility etc.

In this case, instead of the room temperature thermostat, a thermostat that operates in response to water temperature (hot water temperature) may be used.

In the embodiments shown in FIGS. 3 and 4 above, the resistors RH,
The timer relay TX constitutes an energization time detection means, and the heat generating thermostat RH3 and the timer relay TX constitute an energization control switch.

The gas appliance operation control device of the present invention connects a combustion blower to the power supply via an indoor thermostat, and connects a pilot flame detector, main gas valve, delay circuit, and igniter in parallel with the blower. A series connection body is connected to the igniter, and an energization time detection means for detecting energization for a predetermined time or more to the igniter and a pilot gas valve are connected in parallel to the igniter, and the output of the pilot detector is In response to this, a first changeover switch selectively connects the main gas valve and the series connection body to a power source, and a pilot gas valve is selectively connected in parallel to the igniter and the main gas valve. A power supply control switch is provided in the power supply path, through which the second changeover switch is inserted and which cuts off the power supply route in response to the output of the power supply time detection means.

Therefore, it has the following effects.

(1) Since the power source is connected to the indoor thermostat by a combustion blower, pilot flame detector, main gas valve, delay circuit, igniter, pilot gas valve, and energization time detection means, the indoor temperature can be determined in advance. When the temperature exceeds a predetermined set value (based on the indoor temperature thermostat) and the indoor thermostat is turned off, the power supply to each part is cut off, stopping gas combustion and correspondingly stopping the combustion fan.

Therefore, the delivery of combustion air is stopped, and the heat exchanger temperature and room temperature are prevented from being rapidly cooled, and gas can be saved.

Also, since the combustion fan (motor) stops, power can be saved.

(2) When the indoor temperature falls below a predetermined set value and the indoor thermostat is turned on, the combustion blower connected to the thermostat will operate immediately, but since a delay circuit is connected to the igniter, the igniter will not work. does not operate immediately, but operates after a delay of the delay time caused by the delay circuit.

Therefore, the combustion fan starts rotating and the air in the heat exchanger is sufficiently replaced before the igniter is activated (pre-purge), so there is no risk of explosion and ignition, and it is safe to use.

(3) The output of the pilot flame detector controls the energization of the igniter and the energization time detection means for the igniter, and the power supply path is cut off when the energization time detection means continues to be energized for a certain period of time or more. Therefore, if the gas supply is stopped for a relatively long time, the energization control switch is activated and the power is cut off.

Therefore, when they dissipate again, they are safe because they will not be re-ignited.

In addition, if the igniter fails, for example, and the ignition does not start after a certain period of time, the power is similarly cut off, so all soot valves are closed and power to the igniter is stopped.

Therefore, it is even safer.

[Brief explanation of drawings]

FIG. 1 is a diagram of a gas combustion system of an FF type gas hot air heater which is the background of this invention and to which this invention can be applied. FIG. 2 is an electrical circuit diagram of an operation control device as an interesting prior art to this invention. FIG. 3 is an electrical circuit diagram of an embodiment of this invention. FIG. 4 is an electrical circuit diagram of another embodiment of this invention. FIG. 5 is a gas combustion system diagram of still another embodiment of this invention. In the figures, the same reference numerals indicate the same or corresponding parts, W is the main gas valve, PV ha pilot gas valve, FX is the pilot flame detector, BM is the combustion fan motor, HF is the hot air fan FM, the warm air fan motor, HEX
is a heat exchanger, ps is a power switch, c is a self-holding relay, WPS is a wind pressure switch, DLY is a delay circuit, IGN is an igniter, RH is a heating resistor, RH3 is a heating thermostat, TX is a timer relay, AV is all It's a gas valve.

Claims (1)

[Scope of Claim for Utility Model Registration] A combustion blower is connected to the power supply via an indoor thermostat, and in parallel with this blower, a series connection of a pilot flame detector, a main gas valve, a delay circuit, and an igniter. and for this igniter, an energization time detection means for detecting energization for a predetermined time or more and a pilot gas valve are connected in parallel, and the pilot gas valve responds to the output of the pilot detector. a first selector switch that selectively connects the main gas valve and the series connection body to a power source; and a second selector switch that selectively connects the pilot gas valve to the igniter and the main gas valve in parallel. 1. An operation control device for gas appliances, characterized in that an energization control switch is inserted in a power supply path and interrupts the power supply path in response to the output of the energization time detection means.