JPH0629650B2 - Steam generator - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam generator for heating a bathroom air or the like by filling a bathroom or the like with steam and using it for a sauna or the like.

2. Description of the Related Art In general, a steam generator of this type for boiling water to generate steam has a can body 24, a steam outlet 26 in an upper space of the can body 24, and a lower water body as shown in FIG. Water supply port 25
A drain port 31 is provided at the bottom of the can body 24, and an electric heater 23, which is a heating source in the can body 24 and is located in the water, is provided. The electric heater 23 generates heat to heat the water 34 in the can body 24. Then, it is boiled to generate steam 35, and the steam 35 is sent out from the steam outlet 26 through the steam pipe 30. The steam pipe 30 is piped and opened to the atmosphere such as a bathroom. Further, the drainage pipe 32 connected to the drainage port 31 and the drainage valve 33 drain the water 34 in the can 24. In addition, the electric heater 2 for heating the water 34 in the can body
The output of 3 has a function of controlling the output of the electric heater 23 by the controller 38 to keep the room temperature constant when the room temperature in the bathroom or the like reaches the set temperature.

In the above structure, the water 34 in the can 24 is reduced by continuously generating steam, but the water level sensor 27 and the sewage level sensor 28 provided in the can 24 cause the water supply valve to operate. Water is supplied from the water supply port 25 to the inside of the can body 24 so that the water level is always controlled within the range where both the water level sensors are located by controlling the opening / closing. Since the water 34 in the can body 24 is constantly boiling and evaporating, scale components (calcium, magnesium, silica, etc.) contained in the water are deposited and concentrated, and the inner wall of the can body 24 and the electric heater 23.
Adhered to the surface of. It is shown in FIG. Then, the water 34 in the can 24 is drained from the drain valve 33 when the steam generator is stopped. This is to drain the water in which the scale components are concentrated to reduce the scale adhesion. Stopping the steam generator means turning off the power to the electric heater 23,
When full temperature as shown in Figure 6 to reach the set temperature (e point), because it controls the output of the electric heater 23 in the controller 38, the pressure in the can body 24 has a P _{2 'from} P ₂ However, since the tip of the steam pipe 30 is opened by this stopping operation (point f), the pressure P ₂ in the can 24 suddenly drops to P ₂ ′, and the pressure applied to the drain valve 33 is increased. Is only HmmH ₂ O (g point) which is the position head. On the other hand, can body 24
The electric heater 23 is cooled and contracts at the stop point f of the steam generator. At this time, due to the difference in the coefficient of thermal expansion between the can 24 and the electric heater 23 and the attached scale 37,
The scale 37 is peeled off to become a scale piece 37 ', which falls and accumulates on the lower portion of the can body 24. The school piece 37 'that has dropped near the drainage port 31 is discharged outside the device together with the drainage (point h).

Problems to be Solved by the Invention However, since the specific gravity of the school is about 2 because it is larger than the specific gravity of water, it remains sunk and is not completely discharged by the pressure of the water head H at the time of drainage, but is gradually accumulated on the can body 24. In order to solve this problem, a method has been adopted in which a pump 36 is provided downstream of the drain valve 33 and the pump 36 is forcibly pulled to drain the water. However, there is a problem that the scale piece is caught in the pump 36.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to prevent accumulation of scale pieces in a can body with a simple device without providing a discharge pump.

Means for Solving the Problems The present invention, in order to solve the problems, a can body having a steam outlet and a water supply port, and a heating source for heating the can body to boil the water inside, A water supply pipe for sending water to the can body, a drain pipe and a drain valve for draining water from the can body, and a stop operation to increase the output of the heating source to increase the pressure inside the can body, and then open the drain valve. It is provided with a controller for stopping the heating source output.

Operation According to the present invention, with the above configuration, the output of the heating source is increased by the stop operation of the steam generator, the pressure inside the can is increased, and then the drain valve is opened and the output of the heating source is stopped. Therefore, the drainage can be vigorously performed by the increased pressure inside the can, so that the scale pieces that are peeled off and dropped in the can can also be efficiently discharged.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings. In FIGS. 1 to 3, a burner 1 as heating means is arranged below a can body 2 with a constant combustion space. In the can body 2, a steam outlet 5 in the upper space, a water supply port 4 in the lower water, and a water supply valve (not shown) are controlled to open and close by a water level signal to keep the water level in the can body 2 within a certain range. A water level sensor 6 and a sewage level sensor 7 are provided, and the can body 2
A large number of fins 3 that absorb the combustion heat of the burner 1 are welded to the outer peripheral surface of the. Further, a water supply pipe 8 connected to the water supply port 4 of the can body 2 and a drainage port 9 branched from the water supply pipe 8 are provided, and a drainage pipe 21 connected to the drainage port 9 and the drainage pipe 2
1, a motor 1 and a ball 1 which is rotated by this motor via a shaft 16 to open and close the valve seat 14 of the drainage pipe 21.
And a drain valve 12 composed of three. Besides, a controller 11 for controlling the combustion amount of the burner 1 is provided. That is, the controller 11 makes the burner 1 the maximum output when the start switch 11a is operated, and when the set room temperature is reached, proportionally controls the combustion amount of the burner 1 by the temperature signal to maintain the room temperature at the set temperature and the stop switch 11b. When operated, the maximum output delay means 11c operates to maximize the combustion amount of the burner 1 for a predetermined time through the burner control units 4 and 0, and when the pressure inside the can body 2 reaches P ₁ , the pressure detected. The drain valve drive signal section 11d receives the signal from the detection section 40 to open the drain valve 12, and the burner control section 11e similarly extinguishes the burner 1. The controller 11 also receives signals from the upper and lower water level sensors 6 and 7 to control the opening and closing of the water supply valve.

In the above configuration, when the start switch 11a is operated,
The burner 1 is supplied with fuel from the proportional valve 41 and burns so that it burns with maximum capacity. By this combustion, the fins 3 absorb the combustion heat, the water 19 in the can body 2 is heated and boils, and the steam 20 is generated. The generated steam 20 is sent out from the steam outlet 5 through the steam pipe 18. The steam pipe 18 is extended and opened to the atmosphere such as a bathroom. The water 19 in the can 2 evaporates and decreases,
Water is supplied from the water supply port 4 so that the water level is kept within the range where the upper water level sensor 6 and the lower water level sensor 7 are located. Since the water 19 in the can body 2 is constantly boiling and evaporating, the scale component contained in the water is deposited and concentrated, and the scale adheres to the inner wall of the can body 19 (shown in FIG. 2). . Then, as the steam generator is stopped by the stop switch 11b, the water 19 in the can body 2 is discharged from the drain valve 12, so that the can body 2 is rapidly cooled and contracts. At this time, due to the difference in thermal expansion coefficient between the can body 2 and the attached scale 22, the scale 22 is peeled off to form a scale piece 22 '.
Fall to the bottom of.

The steam generation and the drainage process by the drain valve after the stop will be described with reference to FIG. 3. The pressure inside the can body 2 reaches the set temperature when the start switch 11a is operated as described above ( Until the point a), the burner 1 burns at the maximum due to the proportional valve 41, so the pressure becomes P ₁ , and after the bathroom temperature reaches the set temperature (point a), the controller 11
Controls the combustion amount of the burner 1 proportionally, so the pressure is P ₁ ′.
Becomes During drainage, when the stop switch 11b is operated to stop the steam generator (point b), the maximum output delay means 11c operates, the proportional valve 41 is controlled via the burner controller 11e, and the burner 1 burns. The amount is once again maximized to raise the internal pressure of the can to P ₁ . Then, after the pressure rises (point c), the drain valve drive signal unit 11d operates in response to the signal from the pressure detection unit 40 to move the motor 17 to open the drain valve 12, and in the same manner as the pressure detection unit 40.
The proportional valve 41 is closed by the burner control unit 11e which receives the signal of (1) to extinguish the burner 1. Therefore, the drainage can be made vigorous by the pressure of P ₁ , and the scale piece 2 dropped in the can body 2
Since 2'can also be efficiently discharged, it is not accumulated in the can body.

The heating source is not limited to the burner 1 and may be an electric heater.

Effects of the Invention As described above, according to the present invention, the following operational effects can be expected.

(1) After stopping the steam generator, increase the output of the heating source more than usual and increase the pressure inside the can.
Since the drain valve is opened to stop the operation of the heating source, the drainage efficiency and the scale piece discharge efficiency are high, and the scale piece accumulation can be prevented in the can body.

(2) The drainage pump is unnecessary, the scale piece is not caught in the pump, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a steam generator showing an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1, and FIG. FIG. 4 is a vertical cross-sectional view of a conventional example, FIG. 5 is a cross-sectional view showing the state of scale adhesion and separation on the inner wall of the can and the heater surface of FIG. 3, and FIG.
The figure is a diagram showing changes in the internal pressure of the can, the passage of time, and the output of the electric heater. 1 ... Burner, 2 ... Can body, 4 ... Water supply port, 5 ... Steam outlet, 11 ... Controller, 11e ... Burner control unit (heating source control unit), 12 ... Drain valve.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-48-14902 (JP, A) Actually opened 61-135114 (JP, U) Actually opened 61-69605 (JP, U)

Claims (1)

[Claims] 1. A can body having a steam outlet and a water supply port, a heating source for heating the can body to boil internal water, a heating source control section for controlling the output of the heating source, and a can body. A water supply pipe for sending water and a drain pipe and a drain valve for draining water from the can body, and before the water in the can body is drained, the output of the heating source is kept for a certain period of time.
A steam generator comprising a controller for opening the drain valve and stopping the output of the heating source after increasing the internal pressure of the can by raising the pressure inside the can more than usual.