JP2536486B2 - Hot water circulation device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hot water circulation device that uses vapor pressure to supply hot water heated by a burner to a radiator without using a circulation pump.

[Conventional technology]

Conventionally, as a structure for circulating hot water heated by a kettle in a radiator, there is a structure that uses a vapor pressure that can be used even in a place where power is not supplied, instead of a circulation pump.

That is, JP-A-52-141044 and JP-B-57-53929,
Japanese Patent Application Laid-Open No. 57-23731, which is proposed by the applicant, discloses that a water heating can having a water storage can that can be sealed is heated by a burner, and hot water in the water heating can is pressure-fed to a radiator by the generated vapor pressure. A structure is described in which hot water in the kettle is pushed out to an open tank that is located higher than the kettle via the, and the water stored in the open tank is returned to the kettle via a valve. The existence of a system capable of performing is well known.

As a well-known valve structure for returning the water in the open tank to the kettle, the conventional structure of Japanese Utility Model Publication No. 57-53929 and Japanese Unexamined Patent Publication No. 57-237 are known.
No. 31 discloses a check valve, and when using a burner with a small heating value, it is common to use a check valve.

On the other hand, the biggest problem with this type of hot water circulation system is that stable operation is difficult to obtain.When using the conventionally known check valve, if the calorific value of the burner is increased, the water in the open tank will be slightly When it entered, it boiled instantly to generate a large amount of steam, and this steam pressure closed the check valve, resulting in the worst state of being unable to circulate. And, the one that obtains stable hot water circulation with the check valve is
The calorific value of the burner needs to be smaller than the capacity of the kettle, the interval for pumping the circulating water is long, and the circulating water amount is extremely small.

For this reason, a system to change the calorific value of the burner was considered for the initial response (see the explanation of the conventional example in Japanese Utility Model Publication No. 55-143413), but it is necessary to turn the heat source switch on and off repeatedly, There is a problem that the flow of hot water is intermittent operation with a long stop interval.

Japanese Utility Model Publication No. 57-53929 proposes replacing this check valve with a solenoid valve controlled by a liquid level switch.
No. 52-141044 also discloses a proposal to use a solenoid valve (a solenoid-driven on-off valve) under the control of a liquid level switch. As an example of Japanese Utility Model Publication No. 57-53929, the flow path of the solenoid valve is required to have a sufficient thickness so that the high-pressure steam in the kettle escapes at the time of opening and at the same time, the water can flow from the open tank to the kettle. Further, as another configuration, there is disclosed a configuration in which an open pipe that communicates between a closed kettle and an upper space of an open tank is provided, and a pressure relief valve that operates according to a signal of a liquid level switch is attached to the open pipe.

[Problems to be Solved by the Invention]

By the way, in a hot water circulation system that does not use a circulation pump, in order to avoid the worst case of inability to circulate, it is necessary to pour water into an open tank while hot water still remains in the kettle. The valve is opened directly or indirectly by surface detection. Furthermore, in order to ensure the stability of operation, JP-B-57-53929 and JP-A-57-57929
No. -23731 shows the need for an atmospheric release valve to release the pressure of the kettle.

Although these systems were able to avoid the worst case of inability to circulate, in this system, the amount of hot water sent to the radiator per cycle is the amount of water corresponding to the difference between the high level and the low level of the liquid level detector. The amount of water circulating in a certain amount of time is small compared to the size of a kettle, and when returning the water stored in an open tank to the kettle, a large amount of vapor pressure escapes from the kettle, causing a large energy loss. It was a problem to improve.

[Means for solving the problem]

The present invention opens and closes a check valve or an on-off valve by another detector in place of the conventional liquid level switch, and an open tank 1 communicating with the atmosphere and a seal provided at a position lower than the open tank 1 can be sealed. 2 is provided with a hot water can 2 which forms a water storage can body, and a radiator 3 to which hot water of the hot water can 2 is supplied. The open tank 1, the hot water can 2, the radiator 3 and the open tank 1 are connected by a circulation pipe 4, and the circulation is performed. A water circulation path is formed by the pipe 4, and an opening / closing valve 5 is attached to a circulation pipe 4 ′ in a portion of the circulation pipe 4 which connects the open tank 1 and the kettle 2 to a high position when the opening / closing valve 5 is opened. Water from the open tank 1 flows into the kettle 2, and hot water is pumped to the open tank 1 via the radiator 3 by the vapor pressure generated in the kettle 2 when the open / close valve 5 is closed, and the open / close valve 5 that repeats opening / closing forms a circulation path. In the circulation pipe 4 In the circulation device in which warm water flows by operation, one end of the circulation pipe 4 ″, which is a portion of the circulation pipe 4 that communicates the boiling water can 2 and the radiator 3, is connected to the bottom surface of the boiling water can 2 and 2 or a boiling start detection switch 6 for opening the open / close valve 5 is provided in the vicinity of the hot water can 2 and immediately after the open / close valve 5 is opened, the hot water can 2 is connected to the open tank 1 and the hot water can 2 in the circulation pipe 4 '. The steam and the supply water pressure of the open tank 1 are balanced so that the water in the open tank 1 can smoothly flow into the kettle 2 with the progress of emptying.

Further, the air-cooling start detection switch 6 is composed of a temperature switch 6'attached to a circulation pipe 4 "in a portion of the circulation pipe 4 facing from the water boiler 2 to the radiator 3, and the circulation pipe 4" has a temperature of about 100 ° C or more. If it changes to a temperature that contains steam,
Most of the hot water in the kettle 2 was pumped out and sent out, and the start of the empty heating in which the amount of steam generated rapidly decreased could be detected.

Further, the air-cooling start detection switch 6 is composed of a pressure switch 6 ″ attached to the boiling water can 2, and when the positive pressure drops to almost atmospheric pressure, it is the result that all the hot water in the boiling water can 2 is sent to the radiator 3, Since the kettle 2 is in an empty state,
By setting the detection pressure of the pressure switch 6 ″, it is possible to detect the start of the boiling of the water heating can 2.

[Action]

According to the present invention, as a signal for starting water supply from the open tank 1 to the kettle 2, an empty-water start detection switch 6 is provided instead of the signal of the water level detector which is an operation signal of the conventional on-off valve 5. Since one end of the circulation pipe 4 ″ that connects the kettle 2 and the radiator 3 is connected to the bottom of the kettle 2, the entire amount of hot water in the kettle 2 to be heated is sent to the radiator 3 and partially heated. When the start of the
Operates to open the on-off valve 5.

That is, at this time, since the kettle 2 is not completely in an empty state, the vapor pressure of the kettle 2 still remains.
When the on-off valve 5 is opened, the circulation pipe 4'which connects the open tank 1 and the kettle 2 is filled with water, and the vapor of the kettle 2 flows back through the circulation pipe 4'and the circulation pipe 4 ' At the contact portion with the water in ′, a part of the material is absorbed and liquefied by water, and tries to escape to the open tank 1.

However, the vapor pressure of the kettle 2 is gradually decreasing,
When the water pressure flowing down from the open tank 1 to the kettle 2 becomes high, the water in the open tank 1 fills the circulation pipe 4 ′ in association with this pressure drop, and then flows into the kettle 2 in due time. The water condenses the steam contained in the upper space of the kettle 2 and the internal pressure of the kettle 2 becomes a strong negative pressure, and the water in the open tank 1 is forcibly sucked, so that the kettle 2 is filled with water.

After that, when the on-off valve 5 is closed, the heated kettle 2 again generates a large amount of steam, hot water is sent to the radiator 3 by this steam pressure, and the hot water circulation system can operate stably. It has become.

〔Example〕

Referring to the drawings showing an embodiment of the present invention, 1 is an open tank for communicating with the atmosphere, 2 is a kettle having a water storage can body that can be sealed and is provided at a position lower than the open tank 1, and 3 is hot water obtained in the kettle 2. The open tank 1, the kettle 2, the radiator 3, and the open tank 1 are connected by a circulation pipe 4 to form a circulation path.

Reference numeral 4'denotes a circulation pipe that connects the open tank 1 and the kettle 2 in the circulation pipe 4, and 5 denotes an opening / closing valve attached to the circulation pipe 4 '. Before use, the opening / closing valve 5 is opened to open the opening tank 1. When water is poured, the water will pass through the on-off valve 5
-Stop pouring water when a small amount of water flows into the open tank 1 after flowing into the radiator 3 and circulation pipe 4.

Reference numeral 8 is a burner for heating the kettle 2, and when the burner 8 is ignited with the opening / closing valve 5 closed, the kettle 2 is heated,
There is no escape path for the generated steam, and the steam pressure pressurizes the water surface of the kettle 2.

Reference numeral 4 ″ denotes a circulation pipe that connects the water heater 2 and the radiator 3 in the circulation pipe 4, and the hot water pressurized in the water heater 2 is supplied to the radiator 3 via the circulation pipe 4 ″. Reference numeral 4 is a circulation pipe that connects the radiator 3 and the open tank 1 in the circulation pipe 4. The hot water pumped to the radiator 3 is cooled by the radiator 3 to become water, and the circulation pipe 4 opens the tank. Set back to 1.

In this way, when the hot water in the kettle 2 is sent to the radiator 3, the on-off valve 5 is opened by the signal from the liquid level switch and the water in the open tank 1 at the upper position flows into the kettle 2. Even if the volume of the upper space of the kettle 2 decreases due to the rise in the water level of the kettle 2, since the upper space of the kettle 2 is almost filled with steam, the volume becomes small when the steam condenses, and It becomes a negative pressure, and water can be replenished by suction from the open tank 1 to the kettle 2.

Further, since the hot water mixed with steam is broken in the circulation pipe 4 ″ and the radiator 3, the air bubbles are mixed with the hot water, resulting in a light airlock state, and even if the internal pressure of the kettle 2 drops. The water in the open tank 1 flows into the kettle 2 through the circulation pipe 4 ′ without immediately flowing back from the radiator 3 side.

Reference numeral 9 denotes a liquid level detector attached to the open tank 1 which outputs a signal of closing the open / close valve 5 that has been opened. The liquid level detector 9 detects a drop in the water level of the open tank 1 so that the open / close valve 5 is closed. Then, the internal pressure of the kettle 2 increases again and hot water is sent to the radiator 3. Therefore, the open / close valve 5 is repeatedly opened and closed to form an intermittent hot water circulation cycle.

Incidentally, instead of the liquid level detector 9 for detecting the drop in the water level of the open tank 1 (full capacity of the kettle 2), the passage of time required for the drop in the water level may be indirectly detected by a timer, and the open / close valve 5 is opened. If the on-off valve 5 is closed after a predetermined time from then, the kettle 2 is pressurized again because there is no escape path for the steam.

By the way, when the hot water of the kettle 2 is sent to the radiator 3 and the open / close valve 5 is opened, the water in the open tank 1 flows into the kettle 2, but the hot kettle 2 causes the water to generate steam. The amount of generated steam is related to the amount of heat generated by the burner 8. Since a small amount of steam is generated when the amount of heat generated is small, the steam that has flowed into the kettle 2 is cooled and condensed, and the pressure rise in the kettle 2 does not rise. It is suppressed and water can continue to flow from the open tank 1.

However, when the calorific value of the burner 8 is large, a large amount of steam is immediately generated when the water in the open tank 1 flows into the kettle 2, and even if some steam can be condensed, the amount of steam generated is large, so The pressure rises quickly, and the generated steam pushes back the water flowing from the open tank 1 into the kettle 2.
The water cannot flow from the open tank 1 to the kettle 2 and the hot water cannot be circulated.

For this reason, conventionally, when water still remains in the kettle 2, the liquid level switch detects the drop in the water level and opens the open / close valve 5, and the high pressure vapor pressure is released through the open tank 1. As a result, although the energy efficiency deteriorates, the reliability of hot water circulation can be obtained.

This invention ensures the reliability of hot water circulation and increases the amount of hot water circulation.
The detector for obtaining the open circuit signal of the on-off valve 5 is proposed in order to improve the energy efficiency.

That is, the circulation pipe 4 ″ in the portion that connects the kettle 2 and the radiator 3 is opened to the bottom of the kettle 2 into which water from the open tank 1 directly flows, and the circulation pipe 4 ″ is opened to the bottom. As a result, the entire amount of hot water heated by the kettle 2 is sent to the radiator 3.

Reference numeral 6 denotes a boiling water start detection switch of the boiling water can 2 or a boiling water can 2 mounted in the vicinity of the boiling water can 2, which is interlocked with an opening / closing valve 5 which repeats the opening / closing, and when the opening / closing valve 5 is opened, the boiling water can 2 is empty. It is set when starting the fire. Further, the on-off valve 5 may be closed after a certain period of time when it is opened by a timer as in the conventional product, or may be closed by detecting the empty amount of the open tank 1 by the liquid level detector 9.

As a specific air-cooling start detection switch 6, a general method of detecting an increase in the temperature of the bottom surface of the boiling water can 2 can be considered for air-water start detection, but the air-heating start detection switch 6 of the embodiment shown in FIG. Is composed of a temperature switch 6 ′ attached to the circulation pipe 4 ″ of the circulation pipe 4 facing from the kettle 2 to the radiator 3, and the bottom of the kettle 2 into which the water in the open tank 1 directly flows. A circulation pipe 4 ″ toward the radiator 3 is connected to the opening so as to open.

Therefore, after almost all of the hot water heated by the kettle 2 is sent to the radiator 3, the hot water mixed with steam flows out to the circulation pipe 4 ″, and when the empty heating starts, the heated steam is sent out. The temperature of the circulation pipe 4 ″ changes from the liquid temperature (less than 100 ° C. in water without mixing of chemicals) to a temperature including vapor of approximately 100 ° C. or more. Therefore, this time is the time when the start of the empty heating is started, and the start of the empty heating can be detected by monitoring the temperature by the temperature switch 6.

Further, the emptying start detection switch 6 of the embodiment shown in FIG. 2 comprises a pressure switch 6 ″ attached to the kettle 2, and while hot water remains in the kettle 2, a large amount of steam is generated and the kettle 2 is heated. Keeps high pressure.

Then, with the start of the empty heating, the generation of steam decreases toward zero, the internal pressure of the kettle 2 also gradually decreases, and the end of the circulation pipe 4 forming the hot water circulation path is opened to the atmosphere by the open tank 1. Since there is no pressurization of the kettle 2 from the side of the circulation pipe 4 ″ that connects the kettle 2 and the radiator 3, the pressure of the kettle 2 that has been completely boiled drops to almost atmospheric pressure. Therefore, by monitoring the pressure change of the kettle 2 with the pressure switch 6 ″, the start of the empty heating can be detected.

If the on-off valve 5 is opened before the start of empty heating, the internal pressure of the kettle 2 will be high, and the steam will rise through the circulation pipe 4'through the open tank 1 and into a lumpy bubble and rise for a moment. A phenomenon occurs in which water in the open tank 1 flows into the circulation pipe 4 ′ whose pressure has dropped, and by repeating this, vapor remains in the circulation pipe 4 ′ as air bubbles and an airlock phenomenon occurs. When the airlock phenomenon occurs, the flow path resistance becomes high, and the water in the open tank 1 cannot flow into the kettle 2 and hot water circulation does not function.

By the way, when the kettle 2 starts to be heated, the internal pressure of the kettle 2 is gradually reduced. At this time, if the open / close valve 5 is opened, the circulation pipe 4'on the side of the open tank 1 side of the open / close valve 5 is opened.
The water filled with the water is pushed back to the open tank by the vapor pressure of the kettle 2, while a part of the steam is absorbed and liquefied into the water at the contact portion between the steam and the water. Therefore, the inflow pressure from the open tank 1 and the vapor pressure trying to escape to the open tank 1 are balanced in the circulation pipe 4 ', and the water in the open tank 1 flows through the circulation pipe 4'as the internal pressure of the kettle 2 decreases. Fill and kettle 2
Flows into.

If the water in the open tank 1 flows into the kettle 2 on the verge of becoming empty, the water contained in the water cools and condenses the steam contained in the upper space of the kettle 2, conversely the internal pressure of the kettle 2 is negative. As a result, the water in the open tank 1 is forcibly sucked, so that the kettle 2 is smoothly filled with water and hot water circulation becomes possible.

5'is a check valve installed in place of the on-off valve 5 in the circulation pipe 4'of the part that connects the open tank 1 and the kettle 2; 10 is an open pipe that connects the upper part of the kettle 2 and the upper part of the open tank 1; Reference numeral 7 denotes a pressure relief valve attached to the open pipe 10. The pressure relief valve 7 is interlocked with the above-mentioned air-cooling start detection switch 6, and when the air-boiling start detection switch 6 operates, the pressure relief valve 7 is opened, and the kettle 2 A small amount of the internal pressure that had remained inside was released and became atmospheric pressure. Therefore, a pressure difference that pushes the check valve 5 ′ is generated between the water pressure of the open tank 1 and the water can flow from the open tank 1 into the kettle 2 at the start of emptying.

The electrically operated on-off valve that opens and closes the water channel is large and very expensive, while the check valve 5'which can be used instead of the on-off valve 5 when the calorific value of the burner 8 is very small has a simple structure. Since the pressure relief valve 7 can be a small one that mainly opens and closes the gas flow path, the open pipe 10
Even if the pressure relief valve 7 and the check valve 5'are combined with each other, the overall structure is less expensive than the case where an electrically operated on-off valve is used. Further, the pressure of the kettle 2 when it starts to be empty is close to the atmospheric pressure, and even if the pressure release valve 7 is opened, the vapor pressure that escapes to the open tank 1 is very small, and the energy loss due to vapor is small. It is a waste.

Reference numeral 11 denotes a cylindrical water chamber that covers the outer circumference of the kettle 2. The cylindrical water chamber 11 is located in the middle of the circulation pipe 4 in the part that connects the radiator 3 and the open tank 1 to each other. The water returned to the open tank 1 is being reheated. Further, even when steam is mixed with the heat-dissipated water returned from the radiator 3 to the open tank 1, the steam is liquefied in the large-capacity cylindrical water chamber 11,
Even if the end of the circulation pipe 4'is opened in the open tank 1, the release of steam from the open tank 1 is suppressed.

〔The invention's effect〕

As described above, in the present invention, as the signal for inflowing water into the kettle 2 as in the conventional product, the liquid level switch or another detector that operates in the same manner is not used, and the emptying start detection switch 6
Since the opening of the open / close valve 5 is opened by detecting the start of emptying by the above, the water in the open tank 1 surely flows into the kettle 2 and hot water is sent to the radiator 3 until the kettle 2 is completely empty. Therefore, the reliability of hot water circulation is increased, and the amount of hot water sent out in one cycle is increased.

Therefore, as compared with the case where the liquid level switch outputs the open circuit signal of the open / close valve 5 while the hot water remains in the boiling water can 2, it is desirable that the open / close valve 5 can be opened immediately after the time when the local boiling is started. From the above, there is an effect that the steam remaining in the kettle 2 is cooled by the inflowing water and conversely promotes the inflowing. Furthermore, since the amount of warm water sent out in one cycle is increased, the circulating water amount per constant time is This is an increase over conventional products.

When the on-off valve 5 is opened and water is poured into the kettle 2 after the kettle 2 has caused empty heating, the water can 2 is overheated and the injected water instantaneously vaporizes and the internal pressure rises. In addition to the inability to inflow of water, the phenomenon that water in the circulation pipe 4 ″ is pushed back from the open / close valve 5 to the open tank 1 due to the vapor pressure, and the circulation of hot water is disabled. As described above, in the present invention, the on / off valve 5 is opened by detecting the start of the empty heating, so there is no such trouble.
This is a reliable circulation of hot water.

Further, as the empty-boil start detection switch 6, a temperature switch 6'can be attached to a circulation pipe 4'of a portion that connects the water heater 2 and the radiator 3 to detect the empty-boil,
The change in temperature and pressure of the circulation pipe 4 ″ makes it possible to detect the progress from the boiling state to complete boiling, and functions as the boiling start detection switch 6.

A pressure switch 6 ″ attached to the kettle 2 can be used as the emptying start detection switch 6.
By monitoring the state of the change in pressure, it becomes possible to detect the progress from the boiling state to complete boiling, and this functions as the boiling start detection switch 6.

[Brief description of drawings]

1 and 2 are sectional views showing an embodiment of the product of the present invention. 1 ... open tank, 2 ... can, 3 ... radiator, 4 ...
... Circulation pipe, 5 ... On-off valve, 6 ... Empty-fire start detection switch, 6 '... Temperature switch, 6 "... Pressure switch

Claims (3)

(57) [Claims] 1. An open tank 1 communicating with the atmosphere, a hot water can 2 provided at a position lower than the open tank 1 to form a water storage can that can be sealed, and a radiator 3 to which hot water of the hot water can 2 is supplied. The open tank 1, the kettle 2, the radiator 3, and the open tank 1 are connected by a circulation pipe 4, and a water circulation path is formed by the circulation pipe 4, and the open tank 1 and the kettle 2 are connected in the circulation pipe 4. The open / close valve 5 is attached to the circulation pipe 4'which communicates with the open / close valve 5, and when the open / close valve 5 is opened, the water in the high-position open tank 1 flows into the kettle 2 and when the open / close valve 5 is closed by the steam pressure generated in the kettle 2 Hot water is pumped to the open tank 1 via the radiator 3, and the hot water can flow in the circulation pipe 4 by intermittent operation in the circulation pipe 4 that forms a circulation path by the open / close valve 5 that repeatedly opens and closes. 2 and radiator 3 are connected One end of the circulation pipe 4 ″ of the part to be connected is connected to the bottom of the kettle 2, and an empty-boil start detection switch 6 for opening the open / close valve 5 is provided in the vicinity of the kettle 2 and the open / close valve 5 Immediately after the open circuit, the steam in the kettle 2 and the supply water pressure in the open tank 1 are balanced in the circulation pipe 4 ′ in the part that communicates the open tank 1 and the kettle 2, and the water in the open tank 1 becomes the water in the kettle 2 with the progress of emptying. A hot water circulating device characterized by flowing into the. 2. An empty-boil start detection switch 6 is a circulation pipe 4 ″ in a portion of the circulation pipe 4 which faces the radiator 3 from the boiling water can 2.
A temperature switch 6'attached to the temperature sensor 6 ', which detects the start of space-time heating when the circulation pipe 4 "changes to a temperature containing steam of approximately 100 ° C or higher.
The hot water circulation device according to the item. 3. The boiling point start detection switch 6 is composed of a pressure switch 6 ″ attached to the kettle 2 to detect the start of the point-in-time boiling point when the pressure drops from positive pressure to almost atmospheric pressure. The hot water circulation device according to item 1.