JPH027401Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a small water heater consisting of a case equipped with a hot water outlet leading to a faucet and a water intake leading to a water supply pipe, and a burner that is activated when a control circuit is turned on. Regarding improvements.

In order to reduce heating costs, conventional small water heaters of this type are equipped with a flow switch in the water supply pipe that turns on the water only when hot water is used, and the flow switch turns on the burner. There are many types that keep the burner turned off and the burner is always turned off when hot water is not in use.

However, in order to use this type of flow switch, the capacity of the case must be reduced, but on the other hand, when the capacity of the case is reduced, the temperature of the hot water taken out increases, making it inconvenient to use a shower tube. becomes.

Therefore, the present invention was devised in order to solve these problems in the conventional technology, and the capacity of the housing is small (approximately 10 to 15 l/min), and the flow switch and thermostat are The purpose of the present invention is to provide a new compact water heater that can make the use of a shower more convenient and meet the demand for energy conservation.

In order to achieve this purpose, the small water heater of the present invention has a hot water outlet 5 leading to a faucet 6 and a water supply pipe 7.
In a small water heater comprising a case 3 having a water intake port 4 leading to a water heater, and a burner 1 that is activated when a control circuit a is turned on, the control circuit a of the burner 1 has a water intake that is activated when water is supplied. A flow switch F provided on the water supply pipe 7 and the housing 3
Thermostat that turns on and off depending on the temperature of the water inside
The contact r ₂ a controlled by TH is connected in series, and a separate auxiliary switch SW ₂
A self-holding circuit b that holds the control circuit a on is connected by the operation of , and the self-holding circuit b is controlled by the thermostat TH so that the self-holding circuit b is released when the thermostat TH is turned off. It is characterized by

The invention will now be described in detail with reference to illustrative embodiments.

In Fig. 1, A is a small water heater, in which a case 3 is formed in the form of an annular water jacket around a furnace 2 of a kerosene burner 1, and a water inlet 4 and a hot water outlet 5 are connected to the case 3. A thermostat TH for controlling the operation of the kerosene burner 1 is provided in the housing 3 at a location close to the hot water outlet 5.

The hot water outlet 5 communicates with a faucet 6, the water inlet 4 connects to a water supply pipe 7, a pressure relief valve 8 is provided above the connecting portion, and a pressure reducing valve 9 is provided below the pressure relief valve 8. Further, a flow switch F is provided at a portion of the water supply pipe 7 near the pressure reducing valve 9 on the water supply source side.

The kerosene burner 1 atomizes kerosene supplied by the operation of a fuel pump (electromagnetic pump) and jets it from a nozzle using pressure air discharged from a blower operated by a motor, and ignites it by discharge sparks from an electrode rod. This is a conventional method for starting the blower, and only the blower is shown in the drawing.

The furnace 2 is formed into a cylindrical shape so as to enclose and completely burn the combustion gas 11 ejected from the nozzle of the kerosene burner 1, and an exhaust pipe 21 (chimney) is installed at the top. .

31 is an automatic air vent valve provided at the top of the housing 3.

The thermostat TH is designed to turn on and off the operation of the kerosene burner 1 according to the temperature of the hot water inside the housing 3, and the operating section is located near the hot water outlet 5 of the housing 3. Although it is installed so that the temperature sensing part is exposed on the outer surface of the hot water outlet 5 and faces inside the housing 3 near the hot water outlet 5, the temperature sensing part may be installed so as to face the inside of the hot water outlet 5. And the thermostat TH is
When the temperature detected by the temperature sensing part falls below the temperature range set by the operation part, the kerosene burner 1
It is connected to the electric circuit of the electromagnetic pump of the kerosene burner 1, the blower motor, etc. so that the operation of the kerosene burner 1 is turned on and turned off when the temperature rises to that temperature range.

The flow switch F connects the water supply pipe 7 from the water supply source to the water supply pipe 7.
The thermostat is normally turned on when the water supplied to it flows into the water intake port 4, and turned off when the water supply stops.As shown in the electrical circuit diagram in Figure 2, the thermostat TH The control circuit a of the kerosene burner 1, which is controlled by controlled switch
r ₂ a in series, and by operating a separately provided manual auxiliary switch Sw ₂ , the control circuit a
A self-holding circuit b is connected to keep the thermostat TH on, and the self-holding circuit b is controlled by the thermostat TH so that it is released when the thermostat TH is turned off. R ₁ is a relay through which current flows when the auxiliary switch SW ₂ (momentary) is turned on, r ₁ a, r ₁ b are the contacts of that relay R ₁ ,
R ₂ is a relay through which current flows when thermostat TH is turned on, r ₂ a and r ₂ b are contacts of relay R ₂ , and SW ₁ is a power switch.

Next, the operation of the small water heater A of the above-described embodiment will be explained.

In FIG. 2, turn on the power switch _SW1 . When the temperature is low, thermostat TH is on, so relay _R2 is on, so the relay installed in circuit d of relay _R1 is
Contact r ₂ b of R ₂ is also in the on state. Next, when the auxiliary switch SW ₂ is pressed, current flows through the coil of the relay R ₁ , and the contact r ₁ a of the relay R ₁ in the self-holding circuit c that connects A and B across the auxiliary switch SW ₂ is turned on. It is turned on and self-maintained.

On the other hand, when the contact r ₁ b of relay R ₁ in self-holding circuit b connected between c and d across flow switch F of control circuit a and contact r ₂ a of relay R ₂ is turned on, the kerosene burner is turned on. Turn on 1.

To eliminate the self-holding described above, simply turn off the current flowing through the coil of relay _R1 . For that purpose, contact r ₂ a, r ₂ b of relay R ₂
Just turn it off. That is, thermostat TH
When turns off, the coil of relay R ₂ turns off,
Since the contact r ₂ b is also turned off, current no longer flows to the coil of relay R ₁ , and the contacts r ₁ a and r ₂ b are also turned off, and the self-holding is released and the kerosene burner 1
is turned off. Therefore, the thermostat TH
It is self-maintained until it is turned off once. Also, usually the thermostat
When TH is turned on, the coil of relay R ₂ is turned on, so its contacts r ₂ a and r ₂ b are also turned on. At this time, if flow switch F is activated, kerosene burner 1 is turned on and the normal state is turned on. An action is taken.
That is, the burner 1 is
To check, press the auxiliary switch SW ₂ , and when the thermostat TH is activated, the inspection is canceled and normal operation returns.

As described above, according to the small water heater of the present invention, by operating the auxiliary switch, the burner can be turned on until the thermostat is activated, regardless of the flow switch. When starting or for the first time after a long period of outage, such as in the morning, pressing the auxiliary switch will boil the water heater until the thermostat turns off, and then turn off the flow switch after the thermostat turns off. Turns the burner on and off. By doing this,
Usually can be used exactly the same as the instantaneous type,
In addition, it can also have the advantage of a hot water storage type in which the temperature of the hot water is stable.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of the small water heater of the present invention, and FIG. 2 is an electric circuit diagram installed in the same small water heater. Explanation of drawing symbols, A...Small water heater, 1...kerosene burner, 2...furnace, 3...casing, 4...water intake, 5...hot water outlet, 6...faucet, 7... ... Water supply pipe, 8 ... Pressure relief valve, 9 ... Pressure reducing valve, a ...
Control circuit, b, c... Self-holding circuit, d... Relay R ₁ circuit, F... Flow switch, TH... Thermostat, SW ₂ ... Auxiliary switch, r ₂ a...
Contact, 11... Combustion gas, 21... Exhaust stack (chimney), 31... Automatic air vent valve.

Claims (1)

[Scope of utility model registration request] A small water heater comprising a housing 3 having a hot water outlet 5 communicating with a faucet 6 and a water intake 4 communicating with a water supply pipe 7, and a burner 1 that is activated when a control circuit a is turned on. The control circuit a includes a flow switch F provided in the water supply pipe 7 so as to be turned on by water supply, and a contact r ₂ a controlled by a thermostat TH which is turned on and off depending on the temperature of the water in the housing 3. are connected in series, and a self-holding circuit b is connected which holds the control circuit a on by operating a separately provided manual auxiliary switch _SW2 , and the self-holding circuit b is turned off by the thermostat TH. A small water heater characterized in that the thermostat TH is controlled so that the thermostat is released when the water heater is turned off.