JPS6222958A - Steam heating type bath boiler - Google Patents

Abstract

PURPOSE:To remove restrictions in regard to installing a bath boiler and overcome inconveniences of usage, by providing a steam generator connected to the bathtub via two pipes of steam pipe and water return pipe, a check valve in the water return pipe which allows flow only from the bathtub to the steam generator, and a mechanism to control fuel supply to the heating source. CONSTITUTION:The float actuating gas valve 15 is directly connected to the float 13 in the float chamber 12 attached to the steam generator 11, and is closed when the water level of the boiler water 18 drops to as low as a specified limit. The steam pipe 20 has at its end a steam injection nozzle 24, and the return water pipe 21 has a check valve 17 so that the only one way flow from the bathtub 22 to the steam generator 11 is made possible. In this constitution, by automatically repeating the steam generation and return flow of the bathtub water, the bathtub water 23 is heated.

Description

DETAILED DESCRIPTION OF THE INVENTION - Industrial Application Field The present invention relates to a bathtub or bathtub water heating device for home use that uses steam as a heating medium.

・Problems with the conventional technology The bathtubs currently widely used for home use in Japan are of the so-called natural convection circulation type. Its configuration and operation will be explained with reference to FIG.

In FIG. 4, ■ is a bathtub, and 22 is a bathtub. The bathtub 1 and the bathtub 22 are connected by a lower circulation vibe 9 and an upper circulation pipe 1O. The bathtub l is constructed with a gas burner 6 and a heat exchanger 8 as main components, and fuel gas is supplied to the gas burner 6 through a fuel gas supply pipe 2 and a gas solenoid valve 3. Bathtub water 23 can flow into the heat exchanger 8 through the lower circulation pipe 9 and the upper circulation pipe IO.

Prior to use, the bathtub 22 is filled with water 23 to a level above the connection point of the upper circulation pipe IO. The inside of the heat exchanger 8 is also completely filled with water. Subsequently, the gas electromagnetic valve 3 is forcibly opened, and the fuel gas is combusted in the pilot burner 4 and the gas burner 6. Thermocouple 5 is pilot burner 4
The gas solenoid valve 3 is kept open.

The heat generated by combustion in the gas burner 6 is transferred to the heat exchanger 8.
It is conveyed to the water inside. The exhaust gas after passing through the heat exchanger 8 is dissipated into the outside air through the exhaust flue 7.

The water in the heat exchanger 8 is heated by the fuel heat of the fuel gas, and its apparent specific gravity becomes smaller than that of the bath water 23, so that an upward flow of water occurs in the heat exchanger 8. As a result, the bathtub water 23 in the bathtub 22 enters the heat exchanger 8 through the lower circulation pipe 9, and the heated and lightened water returns to the bathtub 22 through the upper circulation pipe 10. The method of heating the water in the bathtub by circulating the water, which has been heated in the heat exchanger 8 and whose specific gravity has been reduced by natural convection into the bathtub, is called the natural convection circulation method, and is currently widely used. This is the operating principle of a bath kettle.

In this natural convection circulation type bathtub, the driving force that circulates water between the heat exchanger and the bathtub is reduced to a minute force due to the difference in specific gravity between the water in the heat exchanger and the wood in the bathtub. Therefore, in order to operate the bathtub stably and reliably, it is necessary to minimize the flow resistance of the water circulation path. For this reason, (1) the structure of the bathtub is such that the water flow path in the heat exchanger is inclined or upright so that the heated wood can circulate smoothly.

(2) The water path from the bathtub to the bathtub via the lower circulation pipe, the heat exchanger, and the upper circulation pipe must be sloped upward in this order to prevent flow stagnation or air bubbles from accumulating in the middle of the path. Do it like this.

As a result, when installing a natural convection circulation type bathtub, (1) it is impossible to reduce the diameter of the upper and lower circulation pipes or to extend their length; In most of the bathtubs currently in use, the inner diameter of the circulation pipe is 45 mm, and the limit of extension is about 50 cm. Therefore, the bathtub must be installed adjacent to the bathtub.

(2) When using the bath, the bath pot and bathtub are installed at a height such that the water level in the bathtub is always higher than the upper circulation pipe, and the upper circulation pipe is placed on the upward slope from the bath pot to the bathtub, and the lower part The circulation pipe must be sloped upwards from the bathtub to the bathtub, and the bathtub cannot be installed in any location without regard to the height relationship with the bathtub.

Furthermore, when using a natural convection circulation bathtub to heat the water in the bathtub, (1) the portion of the bathtub water above the upper circulation pipe is mainly heated, resulting in uneven water temperature distribution within the bathtub; The temperature continues to rise. It is impossible to judge whether the appropriate temperature has been reached unless the temperature is manually and occasionally forcibly stirred.

(2) When the combustion of the heating source is stopped while the temperature of the bathtub water is higher than the outside air temperature, the heat exchanger of the bathtub operates as a cooler. The bathtub water enters the heat exchanger from the upper circulation pipe, is cooled there, and then returns to the bathtub from the lower circulation pipe, creating a water flow that is the opposite of that during heating, and the heated bathtub water ends up being cooled down. .

These restrictions in installing the bathtub and the inconveniences in its use naturally arise from the structure and operating principle of the natural convection circulation bathtub, and cannot be avoided.

As a way to solve these problems with natural circulation bath pots, a method has been proposed in which the bath water is forcibly circulated through the heat exchanger of the bath pot using an electric pump. Not only does the product price increase due to the built-in expensive parts, but it also requires pump power, has a limited lifespan of rotating parts, and is accompanied by the hassle of having to periodically repair and replace parts. ing.

Middle object of the present invention The present invention can be installed without regard to the height relationship with the bathtub, and the circulation pipe can be extended, so there is no restriction on the installation location, and the bathtub water is sufficient when in use. A bathtub water heating device or a bathtub water heating device in which the water temperature is automatically raised with a uniform temperature distribution by stirring is realized without using an electric pump, and the installation limitations of the bathtub water heater in the above-mentioned conventional technology are realized. The purpose is to eliminate the inconvenience and inconvenience of use.

・Structure of the present invention In order to achieve the above object, the present invention is composed of a steam generator that has a heating source and is connected to a bathtub through two pipes, a steam pipe and a water return pipe. It has a check valve in the middle that allows flow only from the bathtub to the steam generator, and has a control mechanism that stops the supply of fuel to the heating source when the water level in the steam generator drops to a specified water level. We propose a steam-heating bathtub that heats bathtub water by alternately repeating the generation of steam in a steam generator and the return of bathwater from the bathtub to the steam generator.

In the bathtub of the present invention, the water in the steam generator is heated by a heating source to become steam, which is sent to the bathtub through the steam pipe, where it exchanges heat with the bathtub water and heats the bathtub water. do. At this time, a check valve is inserted into the water return pipe, so that most of the water vapor is sent to the bathtub through the steam pipe.

As the generation of steam in the steam generator progresses, the amount of water in the steam generator decreases, and when the water level drops to a specified water level, a control device, for example, in the steam generator or in a float chamber communicating with the steam generator, The float inside closes the gas valve connected to the float. As a result, the combustion of the heating source is stopped, the generation of steam in the steam generator is stopped, and the pressure inside the steam generator is reduced to below atmospheric pressure.

This reduced pressure draws bath water through the return pipe and check valve into the steam generator. The return pipe is always filled with bath water, and as soon as the pressure inside the steam generator is reduced, water is immediately injected into the steam generator, and once the water injection starts, the injected water accelerates the cooling of the steam generator. Therefore, the time required to fill the steam generator with water is extremely short.

When the inside of the steam generator becomes full of water, the float in the float chamber rises accordingly, opening the gas valve connected to the float. Combustion of the heating source is restarted and steam generation in the steam generator will take place in due course. The generated water vapor is sent to the bathtub through a steam pipe. In this way, by repeating the generation of steam in the steam generator and the return of the bathtub water to the steam generator, steam heating of the bathtub water is performed in the bathtub.

The supply of steam from the steam generator to the bathtub is driven by the pressure of the steam itself within the steam generator.

The pressure is equal to the passage resistance when steam flows through the steam pipe connecting the steam generator and the bathtub, and is determined by the amount of steam passing through and the diameter/length of the steam pipe. Since it is for household use, it is desirable to keep it below 1 kg/Ctrl'g, and the diameter/extension of the steam pipe is usually selected so that it is about 0.5 kg/Ctrl'g. However, the amount of reverse heat 10.0
Even if the amount of steam equivalent to OOkcal 8 is to flow through a steam pipe with an extension of 10 m, a diameter of 10 mm is sufficient for the steam pipe.

Return of the bath water from the bath to the steam generator is accomplished by the vacuum created in the steam generator when the heating source is turned off. The magnitude of this reduced pressure is usually -0.5 kg/cm
The amount of water sent out in the form of steam by the steam generator is returned in the form of water, so if a pipe with the same diameter as the steam pipe is used as the metering water pipe, the passage resistance of the return water pipe can be ignored. I can do it.

In this way, in the bathtub of the present invention, steam is sent to the bathtub by the pressure of the steam generated in the steam generator, and bath water is sucked into the steam generator by the reduced pressure generated by cooling the steam generator. is the basis of its operation. Moreover, the pressure difference that becomes the driving force is approximately 0.5 in both cases.
kg/crn'. The diameter of the bathtub and bathtub is 10mm.
Two connecting pipes are tied together with wood, but the connecting pipe can be extended to 10 meters or more. With practical soil, there is no need to consider the height difference between the bath pot and the bathtub. The difference in height between the bathtub and the bathtub becomes a problem when the bathtub is lower than the steam generator, and if the difference in height exceeds 5 m, it becomes difficult to draw bath water into the steam generator. It's coming. However, such a case is unlikely to occur for general household use.

Thus, in the present invention, there are no restrictions on the installation location of the bathtub, and it can be installed at a location away from the bathtub, ignoring the height relationship with the bathtub. Only two pipes with an inner diameter of about 10 mm are connected between the bathtub and the bathtub, and there is practically no limit to the length of the pipes.

There are no restrictions on the connection position of the steam pipe and water return pipe to the bathtub.They may be connected to the bottom of the bathtub, or the steam pipe and water return pipe may be connected separately at a separate location.Currently, this is widely used. In bathtubs in practical use, only the bathtub water above the upper circulation pipe is heated unless it is forcibly stirred.
The bathtub water below the upper circulation pipe is hardly heated. In the present invention, the steam pipe is connected to the bottom of the bathtub,
The entire bath water can be heated from the beginning, and the water return pipe can be connected to a location away from the steam pipe, or steam can be spouted from the tip of the steam pipe to forcibly circulate the bath water, It is possible to raise the temperature of the entire water while maintaining a uniform temperature distribution.

The steam generator that constitutes the bathtub of the present invention heats the water therein using combustion gas as a heating source to turn it into steam, and has heat transfer fins on the outside to promote heat transfer from the combustion gas. It can be a surface-mounted can structure or a structure in which a heat transfer section is provided separately from the can body. In the conventional bath kettle, it is necessary to slope the water flow path in the heat exchanger, but in the present invention, such consideration is not necessary at all, and the focus is solely on efficient heat transfer. The steam generator should be designed and manufactured with emphasis on this.

Conventional bathtubs had a drawback in that while the heating source stopped burning, the bathtub's heat exchanger operated as a cooler, cooling the heated bathtub water. . In the bathtub according to the present invention, even if the heating source is left without combustion, the bathwater never circulates by convection between the bathtub and the steam generator.
Therefore, the bath water is not cooled down.

In the present invention, when water vapor, which is a heat transfer medium, is blown directly into the bathtub water, in order to prevent so-called steam hammer from occurring and generating noise, a special It is desirable to install a steam blowing nozzle.If you install a heat exchanger instead of the steam blowing nozzle, exchange heat with the bath water in advance, condense the water vapor, and then mix it into the bath water, noise will be generated. is completely preventable. In this case, it is natural that the bath water can be heated evenly by installing a heat exchanger at the bottom of the bathtub.Furthermore, a backflow prevention valve can be added to the tip of the heat exchanger. If the water in the bathtub is prevented from flowing back into the heat exchanger and steam pipes when the pressure inside the steam generator is reduced, the water in the steam pipes and heat exchanger will be There is no need to remove water, the steam flows smoothly, and the steam pressure in the steam generator does not become excessive.

In the present invention, the steam pipe that sends water vapor from the steam generator to the bathtub and the return pipe that returns bathtub water from the bathtub to the steam generator are separate dedicated pipes. This is a measure to shorten the time required to supply water by bringing bath water close to the steam generator in advance and immediately starting returning the water as soon as the steam generator is slightly depressurized.

The present invention employs a float-driven gas valve directly connected to the float as one of the control mechanisms.

In this way, changes in the water level in the can inside the steam generator are automatically taken care of, making it possible to interrupt and restart the supply of fuel gas without requiring any external control circuit or external power. This makes it possible to avoid using a circulation pump.
A non-powered steam heated bathtub was realized. However, the same operation as the present invention can be performed by using a water level sensor and an electromagnetic gas on-off valve instead of the float-driven gas valve, but in this case, an external power supply and control circuit are required. Of course.

·Example An embodiment of the present invention will be described below.

In FIG. 1, 1 is a bathtub according to the present invention. Fuel gas is supplied to the gas burner 6, which is a heating source, from the fuel gas supply pipe 2 through the gas electromagnetic valve 3 and the float-driven gas valve 15. The gas solenoid valve 3 is driven by a fire extinguishing safety circuit created by a pilot burner 4 and a thermocouple 5. Float driven gas valve 15 is connected to steam generator 11
The flow in the float chamber 12 attached to) 13 and the valve stem 14
The can water 1 in the steam generator 11 is directly connected through the steam generator 11.
The valve closes when the liquid level in No. 8 drops to a specified level.

The steam generator 11 and the bathtub 22 are connected by a steam pipe 20 and a water return pipe 21. A steam blowing nozzle 24 is attached to the tip of the steam pipe 20. A check valve 17 is inserted into the water return pipe 21 to allow water to flow only in the direction from the bathtub 22 to the steam generator 11.

It is assumed that the steam generator 11 of the bathtub 1 is filled with water in advance. Fill the bathtub 22 with water 23 and start operation of the bath pot l.Forcibly open the gas solenoid valve 3.
Pilot burner 4 and gas burner 6 are ignited. When the thermocouple 5 is heated by the pilot burner 4, the thermoelectromotive force of the thermocouple 5 keeps the gas solenoid valve 3 open.

The water 18 in the steam generator 11 is heated by the combustion heat of the gas burner 6, and eventually steam starts to be generated.The generated steam 19 flows into the steam pipe 2 due to its own pressure.
0 into the bathtub 22 and exits through the steam blowing nozzle 24 into the bathtub water 23 . The bathtub water 23 is heated by the heat of condensation of the water vapor.

As the generation of steam in the steam generator 11 progresses and the water level of the can water 18 in the steam generator 11 drops to a specified height, the float 13 in the float chamber 12 attached to the steam generator 11 It follows that and decreases, float 13
The gas valve 15 directly connected to is closed. The combustion of the gas burner 6 is stopped, the generation of steam in the steam generator 11 is stopped, and the pressure inside the steam generator 11 is reduced to below atmospheric pressure. Sucked by this reduced pressure, the bathtub water in the water return pipe 21 passes through the check valve 17 and falls into the steam generator 11 . These water droplets serve as a trigger to rapidly return the bath water to the steam generator 11.

When the bath water flows back into the steam generator 11, the float chamber 1
The float 13 in 2 floats up, and the gas valve 15 opens. The combustion of the gas burner 6 is restarted, and the steam generator 11 is started again.
Steam is then sent to the bathtub 22. In this manner, the generation of steam in the steam generator 11 and the return of the bath water to the steam generator 11 are automatically repeated to heat the bath water 23.

FIG. 2 shows another embodiment of the invention. In this embodiment, a heat exchanger 25 was installed inside the bathtub 22 and connected to the steam pipe 20. The steam sent from the steam generator 11 exchanges heat with the bathtub water 23 in the heat exchanger 25, condenses into water, and then mixes with the bathtub water. In this way, it is possible to avoid the generation of steam hammer and noise when steam is blown into the bathtub water, and quiet operation can be achieved.

FIG. 3 shows an embodiment in which a check valve 26 is provided at the tip of the heat exchanger 25 in the bathtub 22. When stopping the combustion of the heating source and generating reduced pressure inside the steam generator 11 to cause the bathtub water 23 to flow back to the steam generator 11, the check valve 2
6 is not present, bath water 23 is also sucked into the heat exchanger 25 and the steam pipe 20. The water sucked into the steam pipe 20 and the heat exchanger 25 needs to be pushed out into the bathtub water 23 again when the steam generator 11 resumes generating steam. For this reason, the internal pressure of the steam generator 11 will rise abnormally at the beginning of the restart of steam generation. This can be prevented by providing the check valve 26, thereby allowing the steam generator to start up smoothly. Furthermore, it can reduce the withstand pressure of the steam generator, contributing to lower manufacturing costs.

- Effects of the Invention The present invention has the above-described configuration and operation, and provides the following effects.

(1) Only two connecting pipes, a steam pipe and a water return pipe, connect the bathtub and the bathtub, and since they can be extended, the bathtub can be installed at a location away from the bathtub. For general household use, a tube with an inner diameter of about 10 mm can be extended over 10 m, so it can be said that practically the location of the bathtub can be selected independently of the location of the bathtub. -(2) There is no need to consider the height relationship between the bathtub and the bathtub. In practical terms, a bath kettle can be installed at a location higher than a bathtub as long as it is within 5 meters in the vertical direction.

(3) Using coated soft steel pipes or wire-mesh rubber pipes as piping materials, it is only necessary to install two pieces of piping with an inner diameter of about 10 mm between the bathtub and the bathtub, and in addition, the conventional bathtub circulation pipe Unlike the above, there is no need to pay any consideration to the inclination or inclination of the piping, so the installation work is very easy.

(4) Connect the steam pipe near the bottom of the bathtub, or install a heat exchanger at the bottom of the bathtub to send heat to the bottom of the bathtub water as much as possible, or connect the return water pipe at a location far away from the steam pipe. By blowing out steam from a steam blowing nozzle at the tip of the steam pipe, it is possible to raise the temperature of the entire bathtub water while maintaining a uniform temperature distribution.

(5) Even if the combustion of the bathtub remains stopped, natural convection will circulate the bathtub water between the bathtub and the bathtub, and the heat of the bathwater will be radiated into the outside air through the bathtub. do not have.

(8) Unlike conventional baths, there is no need for special measures such as inclination or inclination for the water flow path in the heat exchanger, so the design and manufacture of the heat transfer section is easy and there is a large degree of freedom.

(7) Since an electric pump is not used, there is no need for auxiliary power, and there is no need for periodic repairs or parts replacement.
Excellent durability.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of one embodiment of the bath pot according to the present invention, and FIG.
3 and 3 are explanatory views of different embodiments of the bath kettle according to the present invention, and FIG. 4 is an explanatory view of a bath kettle according to the prior art. 1...Bath pot 16...Valve stem seal 2...Fuel gas supply pipe 17...
... Check valve 3 ... Gas solenoid valve 18.
...Water in the can 4 ...Pilot burner 1
9... Water vapor 5... Thermocouple
20... Steam pipe 6... Gas burner
21... Return pipe 7... Exhaust flue 22... Bathtub 8... Heat exchanger 23... Bathtub water 9... ... Lower circulation pipe 24 ... Steam blowing 10 ...
...Upper circulation pipe Nozzle 11...
... Steam generator 25 ... Heat exchanger 12 ... Float chamber 26 ...
Backflow prevention valve 13...Float 27
... Filter 14 ... Valve stem 15 ... Gas valve

Claims (1)

[Claims] 1. Consists of a steam generator that has a heating source and is connected to a bathtub through two pipes, a steam pipe and a return pipe, and the steam generator is connected to the bathtub in the middle of the return pipe. It has a check valve that allows water to flow only in one direction, and a control mechanism that stops the supply of fuel to the heating source when the water level in the steam generator drops to a specified water level. A steam-heating bathtub that heats bathtub water by alternately repeating generation and return of bathwater from the bathtub to a steam generator. 2. The steam according to claim 1, wherein a heat exchanger is installed in the bathtub, and the steam from the steam generator is indirectly cooled by the bathtub water, condensed, and then mixed into the bathtub water. Heated bath kettle. 3. A heat exchanger with a non-return valve at its tip is installed in the bathtub, and the steam from the steam generator is indirectly heat exchanged with the bath water, condensed, and then mixed into the bath water. The steam-heated bathtub according to claim 1, wherein bath water is prevented from flowing into the heat exchanger when combustion is stopped.