JPS6014084Y2 - steam generator - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a steam generator using an electric heater.

Steam generators, which are generally used in humidifiers, are constructed by installing an electric heater inside a tank that holds water, and installing a water level regulator such as a ball tap on the water supply pipe that supplies water to the tank to adjust the water level inside the tank. The water in the tank is heated to the boiling point using an electric heater to generate steam.

However, in this steam generator, there is a problem in that when the water is heated, components contained in the water precipitate as scale, adhere to the inside of the tank and the surface of the heater, and precipitate.

Here, talking about scale generation, water contains components such as magnesium, calcium, sodium, and silica dissolved in ionic states such as magnesium ions and calcium ions, and by heating water, these ions are removed. is precipitated as solid components such as magnesium and calcium, forming scale.

For example, bicarbonate ion (Ca(HCo3)2) is calcium bicarbonate dissolved in water as an ion.
By heating Ca (HCo3)2 → CaCO3 + H20
+CO2↑ and precipitates in the form of calcium carbonate.

In addition, silica also precipitates and precipitates, which causes scale generation.

Particularly in steam generators, residual water is concentrated due to water evaporation;
When the concentration exceeds that of a saturated solution, scale formation is accelerated.

However, when scale occurs in the steam generator,
Scale adheres to the surface of the heater, which worsens the heat dissipation of the heater and causes the heater's internal temperature to rise abnormally, resulting in damage.Scale adheres to the float of a ball tap, making the float inoperable and water supply to the tank impossible. accidents occur.

Conventionally, as a countermeasure against scale generation in steam generators, a method has been used to remove scale from the tank by draining the water in the tank at regular intervals using a timer, but this method reduces the amount of water used. If the size is large, the water heating efficiency by the heater is poor and it is not only very uneconomical, but also the scale discharged with the water solidifies in the pipes and causes clogging.

Furthermore, in conventional steam generators, ball taps are often used as water level regulators.

In this type of ball tap, the float may get caught in a tank or the like, or the float may corrode and form a hole, causing the float to malfunction or malfunction.

Therefore, there is a problem in that the water position in the tank cannot be adjusted accurately.

The basic concept of the steam generator of the present invention will be described.

A scale collection electrode is installed in the tank, and the component ions contained in the water are sucked into the electrode and deposited as scale, and the scale is adsorbed and collected by this electrode.
This is intended to prevent scale from adhering to tanks, heaters, etc.

That is, as shown in FIG. 1, a positive electrode 2 and a negative electrode 3 are provided in a tank 1, and electricity is applied between the electrodes 2 and 3 through water 4 placed in the tank 1. Calcium ions (Ca+), magnesium ions (M♂+), and sodium ions (Na+) dissolved in water 4
Component ions on the positive side, such as +), are attracted to the negative electrode 3.

Then, the positive side ions are neutralized by receiving negative side electrons (e-) from the negative electrode 3, and are precipitated as solids such as calcium, magnesium, and sodium.

This precipitated material is scale.

In this way, the scale generated from the components contained in the water 4 is collectively collected by the negative electrode 3.

Further, in the steam generator of the present invention, water is supplied into the tank 1 by electrically detecting a drop in the water level in the tank 1 using both electrodes 2.degree.

In other words, the water level detector connected to one of the electrodes detects that the water level inside the tank 1 is lower than both the electrodes 2 and 3, resulting in a non-conducting state between the electrodes 2 and 3. The water supply valve is operated by the operation of the container, and water is supplied to the tank 1.

A specific embodiment of the steam generator of the present invention will be described with reference to FIGS. 2 and 3.

In FIG. 2, numeral 11 is a tank for storing water 4, such as a pan-shaped humidifier.

An electric heater 12 made of, for example, a sheathed heater is provided inside the tank 11 on the lower side, and this electric heater 12 is attached to the side wall of the tank 11 with a mounting nut 13 and connected to a conductor 14 connected to an AC power source 24. .

This electric heater 12 generates heat when energized and heats the water 4 in the tank 11 to its boiling point.

A water supply pipe 15 connected to a water supply source such as a water supply is provided above the tank 11, and the water supply pipe 15 is provided with, for example, a solenoid valve 16 as a water supply valve.

Further, inside the tank 11, a positive electrode 17 and a negative electrode 18 are provided vertically with an interval, and these electrodes 17.1
8 is attached to the side wall of the tank 11 with screws so as to be electrically insulated, and is connected to the DC power supply circuits 21 and 22 via conductive wires (not shown).

These electrodes 17 and 18 are used both for the purpose of collecting scale generated in the water 4 and for the purpose of detecting the water level in the tank 11, and for the former purpose, the negative electrode 1B is used for collecting scale. For the latter purpose, one electrode, for example, the positive electrode 17, is connected to the water supply level detector 20 as a water level detection electrode.

In addition, since the positive electrode 17 is used as a water level detection electrode,
It is provided above the electric heater 12 at the same water level as the negative electrode 18 or at a higher water level than the negative electrode 18 .

Further, inside the tank 11, an electric heater 12 and an electrode 17.
A partition plate 19 is provided to separate the electrodes 17 and 18.
This prevents fluctuations in graft resistance.

Next, the electrode 17.1B, the solenoid valve 16 and the electric heater 1
The electric circuit related to 2 will be described.

The positive electrode 17 is a water supply level detector 20 with a built-in timer relay.
This water supply level detector 20 is connected to a control DC power supply circuit 21, 22.

The negative electrode 18 is connected to a DC power supply circuit 22 on the negative side.

DC power supply circuits 21 and 22 are provided corresponding to an AC power supply 24 via a transformer 23.

Further, the electric heater 12 is connected to an AC power source via a contact 25a of an electromagnetic contactor 25.

The electromagnetic valve 16 is connected to an AC power source via a contact 26a of an electromagnetic contactor 26.

The electromagnetic contactors 25 and 26 are the contacts 20a of the water supply level detector 20.
, 20b to the AC power supply 24.

In addition, 27 in the figure is a humidity controller.

Here, the relationship between the water supply level detector 20 and the electrodes 17.18 will be described.

When the electrodes 17 and 18 are inside the water 4 of the tank 11, the ice 4
A current flows between the two through the electrode 17, resulting in a conductive state.
When the tank 11 is exposed above the water 4, there is no electrical continuity between the two, and this fact is utilized to detect the water level inside the tank 11.

When the water level is below the positive electrode 17 and the positive electrode 17 is exposed, the water supply level detector 20 is activated and the contact 20a
is opened, and when the water level is above the positive electrode 17 and the electrodes 17, 18 are conductive inside the water 4, the water supply level detector 20 operates to close the contact 20a.

In the steam generator configured in this manner, when the water level in the tank 11 is higher than the positive electrode 17, the feed water level detector 2
0 contact 20a is closed, and the electromagnetic contactor 25 is connected to the AC power supply 24 and closes the contact 25a, so the electric heater 12 is energized by the AC power supply and the water 4 in the tank 11 is
heat up.

Note that the humidity regulator 27 is closed. The positive electrode 17 and the negative electrode 18 are energized through the water 4 in the tank 11 with the DC power supply circuit 21 on the positive side and the DC power supply circuit 22 on the negative side.

In this case, the positive potential of the positive electrode 17 (0 volts on the circuit) determines the negative potential of the negative electrode 18, resulting in a potential distribution.

When the positive electrode 17 and the negative electrode 18 are electrically connected in this way, the positive side component ions dissolved in the water 4 in the tank 11 are attracted to the negative electrode 18, and these ions are transferred to the negative electrode 18.
It is given negative electrons from 8 and precipitates as a solid component and adheres to the surface of the negative electrode 18.

That is, the negative ions contained in the water 4 reach the negative electrode 1.
Water 4 is collected and attached as scale to water 4.
The scale generated by the components contained in the liquid can be collected as a whole by the negative electrode 18.

Therefore, scale does not adhere or precipitate inside the tank 11, or scale does not adhere to the surface of the electric heater 12.

Therefore, accidents such as damage to the electric heater 12 due to adhesion of scale can be prevented.

In addition, when the amount of scale attached to the negative electrode 18 increases, the negative electrode 18 is removed from the tank 11, the scale is removed, and used again, or the negative electrode 18 is replaced with a new negative electrode 18.

Next, a case where the water 4 in the tank 11 evaporates and the water level becomes lower than the positive electrode 17 will be described.

In this case, since no current is applied between the electrodes 17 and 18, the water level detector 20 operates and opens the contact 20a, so the electromagnetic contactor 25 is de-energized from the AC power source 24 and opens the contact 25a. Open.

Therefore, the electric heater 12 is de-energized from the electrodes and stops generating heat.

Therefore, when the water level in the tank 11 is low and the amount of water 4 is small, heating of the water 4 by the electric heater 12 is prevented, so-called dry cooking is prevented, and safety is greatly improved.

On the other hand, since the water supply level detector 20 closes the contact 20b, the electromagnetic contactor 26 connects to the AC power supply 24 and closes the contact 26a.

Therefore, the electromagnetic valve 16 is connected to the AC power source and opens, so that water is supplied to the tank 11 via the water supply pipe 15.

When the water level inside the tank 11 rises to the position of the positive electrode 17 due to water supply, conduction is established between the two electrodes 17 and 18.

For this reason, the built-in timer relay in the water supply level detector 20 operates to open the contact 20b after a certain period of time (3 to 4 seconds), so the electromagnetic contactor 26 is disconnected from the AC power source 24 and opens the contact 26a. Open.

As a result, the electromagnetic valve 16 is disconnected from the AC power source and is closed, thereby stopping the water supply to the tank 11.

At the same time, the contact 20a is closed and the electromagnetic contactor 25 is connected to the AC power supply 24, thereby closing the contact 25a.
The electric heater 12 is energized by the AC power source and heats the water 4.

The water level detector 20 detects this decrease in the water level inside the tank 11 using the electrodes 17 and 18, and the electromagnetic valve 16 operates due to the action of the water level detector 20, causing the water to flow into the tank 11. Water is supplied and the water level in the tank 11 is adjusted.

Therefore, there is no need to use a mechanical water level regulator such as a ball tap, and malfunctions and failures that occur in this type of water level regulator can be avoided, and the water level can be easily and accurately adjusted by electrical means.

Note that the electrodes 17.18 have a length of 4-1 and a diameter of 1.57, for example.
A platinum-plated titanium bar with a diameter of 1.5 m is used, and the current conditions for flowing through both electrodes are, for example, DC 12 V and 8 rTIA.

Note that a means for detecting a drop in the water level inside the tank and opening the circuit of the electric heater is not necessarily required.

Further, the water supply level detector may be connected to the negative electrode instead of the positive electrode.

The water supply valve is not limited to a solenoid valve, and may be any valve that opens and closes in response to an electrical signal.

As explained above, the steam generator of the present invention is a simple means in which a positive electrode and a negative electrode are provided in the tank to conduct electricity through water, and the negative electrode collectively collects scale generated by water components. It prevents scale from adhering to various parts such as tanks and electric heaters, and prevents deterioration of the functions of various parts due to scale, allowing for good operation as a steam generator.

Furthermore, there are no problems such as uneconomical costs or clogging of pipes, which are required when replacing the water in the tank at regular intervals to remove scale.

Furthermore, since the water level in the tank is electrically adjusted using the positive and negative electrodes, malfunctions and failures that would otherwise occur when using a mechanical water level regulator can be avoided.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the principle of the steam generator of the present invention, FIG. 2 is a longitudinal sectional front view showing an embodiment of the steam generator of the present invention, and FIG. 3 is a circuit diagram showing an electric circuit. 1...Tank, 2...Positive electrode, 3...
...Negative electrode, 4...Water, 11...
Tank, 12... Electric heater, 15...
・Water supply pipe, 16... Solenoid valve (water supply valve), 17.
...Positive electrode, 18...Negative electrode, 20...
...Water level detector.

Claims (1)

[Scope of utility model registration request] A tank containing water, an electric heater provided inside the tank to heat the water inside the tank, a positive electrode provided inside the tank, and a positive electrode provided inside the tank through which the water inside the tank is heated. a negative electrode that conducts with the water and adsorbs and precipitates positive ions contained in the water; a water level detector that is connected to either one of these electrodes and emits a signal when there is no conduction between the two electrodes; A steam generator comprising a water supply valve that is operated by a signal from the water level detector to supply water to the tank.