JPS599011B2 - gas water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas water heater, and more particularly to an improved structure of its ignition device.

This type of water heater is divided into those that directly ignite the main burner and those that ignite the main burner with an ignition burner that is constantly burning.

The disadvantage of the former is that if the ignition fails, a large amount of raw gas is released and there is a risk of explosive ignition if you do not wait for a while to re-ignite. There is a waste of letting the flames burn, and since the flames are small, they may blow out, so it is necessary to provide a safety device for this purpose.

To deal with this problem, a special gas water heater has been developed that detects the operation of the water supply switch, supplies gas to the ignition burner, ignites it, detects the ignition, opens the gas supply valve to the main burner, and starts combustion. This was proposed in 1972-115342.

However, in such conventional examples, the gas supply valve to the main burner is a solenoid valve, so if you try to make this gas supply valve perform a slow ignition operation, you will need multiple large solenoid valves, which increases the cost. However, the disadvantage was that the control circuit was complicated.

The present invention provides a solenoid valve that adjusts and always maintains at least the flow path to the low pressure chamber in a state where no differential pressure occurs between the high pressure chamber and the low pressure chamber, which are separated by a diaphragm of the hydraulic response device. The above disadvantages are solved by operating the sub burner in a state where a differential pressure is generated between the compartments upon arrival of the ignition confirmation signal, and by providing a slow ignition device in the flow path to the low pressure chamber. The embodiment will be explained with reference to the drawings.

Reference numeral 1 denotes a water passage that connects in this order a water supply port 2, a diaphragm-type water governor 3, a water flow control valve 4, a heat exchanger 5, and a hot water supply port 6. A venturi 7 is formed downstream of the water flow control valve 4, and this venturi 7 is communicated with a low pressure chamber 9 of a diaphragm type hydraulic response device 8 through a low pressure passage 10, and an upstream side of the water flow control valve 4 is communicated with the high pressure chamber 11 through a high pressure passage 12.

Reference numeral 13 indicates a main burner, and 14 indicates an auxiliary burner having a smaller capacity than the main burner for ignition.

15 is a gas passage in which a gas inlet 16, a first electromagnetic valve 17, and a diaphragm-type gas governor 18 are successively connected;
A large-diameter main passage 20 and a small-diameter sub-passage 21 leading to No. 3 are communicated with each other.

22 is a spindle fixed to the diaphragm 23 of the hydraulic response device 8, and the above-mentioned main and sub passages 20 and 21 are connected to the tip of the spindle.
A first gas valve 24 that opens and closes the main passage 20 at the same time and a second gas valve 25 that opens and closes only the main passage 20 are provided. However, the second gas valve 25 is opened after a certain period of time.

Reference numeral 26 denotes a communication passage that communicates the high pressure passage 12 and the low pressure passage 10, and is opened and closed by a second electromagnetic valve 27.

Reference numeral 28 denotes a drainage channel that communicates the low pressure channel 10 with the downstream side of the venturi 7, which is opened and closed by a second electromagnetic valve 27, and a manual drain plug 29 is provided in the channel.

30 is a spark plug that ignites the auxiliary burner 14; 31 is a detection electrode that detects the ignited combustion flame of the auxiliary burner 14; 32 is a diaphragm-type water supply switch that is activated by the water supply pressure when water is supplied into the water passage 1; 33; receives signals from the water supply switch 32 and the detection electrode 31, respectively, and operates the first solenoid valve 1.
7 and the second electromagnetic valve 27, and applies a high voltage to the spark plug 30 as appropriate.

34 is a slow ignition device consisting of a small ball 35 provided in the low pressure flow path 10 near the low pressure chamber 9 and a bypass path 36 that bypasses the small ball 35.

Note that 37 is a passage that communicates the low pressure chamber of the water tanker 3 with the low pressure passage 10.

Next, the operation of the water heater according to the present invention will be explained.
Before water supply starts, the first solenoid valve 17 is closed, the second solenoid valve 27 is opened, and the first and second gas valves 24 and 25 are closed.

First, when water starts to be supplied from the water supply port 2 into the water passage 1,
The pressure of the water is regulated by a water governor 3 and the amount of water is regulated by a regulator 4, which enters a heat exchanger 5 via a venturi 7 and exits from a hot water supply port 6.

During this time, the second electromagnetic valve 27 is opened to open the communication path 26, so both sides of the diaphragm 23 are receiving the same pressure and the hydraulic response device 8 does not operate.

On the other hand, since the water supply switch 32 is activated by the water supply to the water passage 1, the control device 33 opens the first solenoid valve 17 to supply gas from the branch passage 19 to the auxiliary burner 14, and also causes the spark plug 30 to be supplied with gas. A high voltage is applied for a certain period of time.

In this way, when the auxiliary burner 14 ignites and burns, the detection electrode 31 detects the flame, so the control device 33 controls the second solenoid valve 2.
7 closes the communication path 26.

When the communication passage 26 is closed, a pressure difference is generated between the high pressure chamber 11 and the low pressure chamber 9, so that the hydraulic response device 8 gradually moves the spindle 22 by the slow ignition device 34.

Therefore, the first gas valve 24 is first opened to supply a small amount of gas to the main burner 13 from the auxiliary passage 21 and ignited and burned in the auxiliary burner 14, and then the second gas valve 25 is opened to supply the main burner 13 with a small amount of gas. , a large amount of gas is supplied from both auxiliary passages 20, 21 to carry out predetermined combustion.

Note that the supplied gas is adjusted to a predetermined pressure by a gas governor 18.

The water heated by the fuel exchanger 5 becomes hot water and continues to be supplied from the hot water supply port 6, but when the desired amount of hot water is obtained, the water supply is stopped.

Therefore, since the water supply switch 32 is deactivated, the control device 33 returns the first solenoid valve 17 to its closed state and returns the second solenoid valve 27 to its original open state.

Therefore, the gas supply to the main burner 13 and the auxiliary burner 14 is stopped, each burner 13, 14 is extinguished, and the communication passage 26 is opened, so that the hydraulic response device 8 is maintained in an inoperative state.

At this time, when the drain plug 29 is loosened and opened, the residual water in the high pressure chamber 11 and the low pressure chamber 9 passes through the second electromagnetic valve 27 and enters the drain channel 28.
The water is led out into the interior and exits from the drain plug 29.

Incidentally, when the high voltage is applied from the spark plug 30 for a certain period of time and the detection electrode 31 cannot detect it during that period, the control device 33 immediately closes and returns the first electromagnetic valve 17.

Thereafter, for a certain period of time, even if the water supply switch 32 is activated by water supply, the control device 33 does not operate, and waits until the raw gas discharged from the sub-burner 14 is completely discharged outside the vessel.

Here, in another embodiment shown in FIG. 2, the communication passage 26 is eliminated and a second electromagnetic valve 27 is installed in the low pressure flow passage 10.

That is, before water is supplied, the second solenoid valve 27 is closed and the low pressure chamber 9 is closed.
The interior is sealed to prevent the diaphragm 23 from moving even when water supply pressure is applied to the high pressure chamber 11, and the second electromagnetic valve is opened when an ignition confirmation signal arrives due to detection of flame by the detection electrode 31. do it like this.

In the hydraulic response device 8 of the type in which the low pressure chamber 9 is communicated with the atmosphere through a small hole or the like, the small hole or the like may be opened and closed by a second electromagnetic valve 27 as in the other embodiment shown in FIG.

In this way, the present invention includes a main burner that heats a heat exchanger in a water passage, a sub-burner that ignites this burner and is ignited every time water is supplied to the water passage, and a gas supply valve to the main burner as described above. and a hydraulic response device that is activated by the movement of a diaphragm that receives the pressure in the water passage in a high pressure chamber, and at least maintains a state in which no differential pressure occurs between the high pressure chamber and the low pressure chamber, which are separated by the diaphragm of the hydraulic response device. A solenoid valve is provided to adjust and maintain the flow path to the low pressure chamber at all times, and this solenoid valve is operated to a state where a pressure difference between the compartments is generated upon arrival of the ignition confirmation signal of the auxiliary burner, and the flow path to the low pressure chamber is operated. A slow ignition device is installed in the flow path, and the sub-burner is ignited every time water is supplied, and upon arrival of the sub-burner ignition confirmation signal, the solenoid valve in the flow path to the low pressure chamber is activated to reduce the pressure difference between the compartments. Activate the slow ignition device to slowly ignite the main burner.

Therefore, there is no waste in constantly burning the auxiliary burner, and since gas is supplied to the main burner only after both the water supply operation and the ignition operation of the auxiliary burner are performed, the main burner repeatedly fails to ignite and releases raw gas. This eliminates the risk of explosion and ignition.

According to the present invention configured as described above, it is possible to eliminate slow ignition operation, explosive ignition, and prevent wasteful constant combustion by adding a small solenoid valve to the hydraulic response device, so that the conventional solenoid valve This has significant effects such as cost reduction compared to a device that performs the same operation, and also simplifies the control circuit configuration since only one solenoid valve is required to control it.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a gas water heater according to the present invention, and FIG. 2 is a sectional view of another embodiment of the main part. 8...Hydraulic response device, 9...Low pressure chamber,
10...Low pressure flow path, 11...High pressure chamber,
13...Main burner, 14...Sub burner, 24, 25...Gas valve, 27...Second solenoid valve.

Claims (1)

[Claims] 1. A main burner that heats a heat exchanger in the water passage, a sub-burner that ignites this burner and is ignited every time water is supplied to the water passage, and a gas supply valve to the main burner. It consists of a hydraulic response device that is activated by the movement of a diaphragm that receives the pressure in the water passage in a high pressure chamber, and the system is designed to minimize the pressure difference between the high pressure chamber and low pressure chamber, which are separated by the diaphragm of the hydraulic response device. A solenoid valve is provided which adjusts the flow path to the low pressure chamber and maintains it at all times, and when the auxiliary burner ignition confirmation signal arrives, the solenoid valve is operated to generate a differential pressure between the compartments, and the low pressure A gas water heater equipped with a slow ignition device in the flow path to the chamber. 2. The gas water heater according to claim 1, wherein the solenoid valve is a solenoid valve that always opens a water communication path that connects the high pressure chamber and the low pressure chamber of the hydraulic response device. 3. Claim 1, characterized in that the solenoid valve is a solenoid valve that seals a flow path to a low pressure chamber that communicates with a water path of a hydraulic response device before water is supplied, and opens upon arrival of an ignition confirmation signal. gas water heater.