JP2001174059A - Hot-water supplier with heat keeping function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot-water supplier with heat keeping function which can prevent the water held in a closed pipeline from jetting out of an apparatus due to a pressure rise by relieving the pressure rise in the closed pipeline while the hot-water supplier is operated for heat keeping combustion. SOLUTION: The hot-water supplier with heat keeping function is constituted in such a way that, when the supplier is started for heat keeping combustion, the water staying in the closed pipeline including a heat exchanger is heated and the pressure in the pipeline rises. A valve element 32 which moves as the pressure in the pipeline rises and a detecting section 33 for detecting the displacement of the element 32 are installed to a pressure absorbing valve 30 and, when the detecting section 33 transmits a detect signal, the supplier discriminates that the water supplied from the closed pipeline and held in an apparatus is about to jet out of the apparatus and stops the burning of a burner for the heat keeping combustion. Consequently, the abnormal pressure rise in the closed pipeline can be suppressed and the frequency-of-occurrence of such a failure that the water jets out of the apparatus can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to a method for relieving piping pressure of a water heater with a heat retaining function.

[0002]

2. Description of the Related Art Generally, in an instantaneous heating type water heater equipped with a burner, when a hot water supply curan is opened and the flow of water is started, the flow rate of the water is detected to start the combustion of the burner, and the heat is released. Hot water heated in the exchanger is supplied to the outside through a hot water supply curran. Then, when the flow of water is stopped by closing the hot water supply curran, the combustion of the burner is also stopped. In recent years, even when the hot water supply is in standby (when no hot water is supplied), a function of improving the hot water supply performance by pre-heating the water in the water heater to an appropriate temperature (insulated combustion operation function) has been provided. A water heater is provided. This is to prevent cold water from flowing out at the start of hot water supply operation or at the initial stage of re-hot water supply, and to quickly obtain the set hot water supply temperature.

[0003]

However, in general, in the construction of a water heater, the water supply pipe is often composed of a resin pipe, and therefore the high-temperature water generated in the water heater flows backward to break the water supply pipe. Usually, a check valve is provided in the water supply pipe portion of the water heater to prevent such a situation. Thereby, when the hot water supply curan is closed and the hot water supply is completed, the hot water supply pipe including the heat exchanger becomes a closed pipe. If the warm combustion operation is performed in this state, the water in the closed pipe will be heated, and there is a problem that the pressure in the closed pipe including the heat exchanger increases. If the pressure in the closed pipe is large, the pipe may be damaged, water leaks, etc. may occur with it. Overpressure safety valve was provided. However, in the conventional overpressure safety valve, since the pipe pressure is released to the outside and the water in the pipe is jetted to the outside of the instrument, undesired things such as wetting around the instrument may occur.

Accordingly, the present invention solves the problems of the conventional apparatus, alleviates a rise in the pressure in the closed pipe during the insulated combustion operation, and causes the water retained in the closed pipe to blow out of the apparatus due to the increase in pressure. It is an object of the present invention to provide a water heater with a heat retaining function that can prevent the occurrence of the problem.

[0005]

Means for Solving the Problems To achieve the above object, a water heater with a heat retaining function of the present invention is provided with a water inlet pipe, a hot water supply pipe, a heat exchanger, and a burner for supplying hot water. Even if not, by burning the burner, it is a water heater with a heat retention function capable of performing a heat retention combustion operation of water in a closed pipe including the heat exchanger,
A pressure fluid is received from a pressure introduction passage leading to the closed conduit,
When the pressure in the closed pipe rises abnormally, in a device equipped with a pressure absorption valve that releases pressure by discharging water to the outside, with the pressure increase in the closed pipe due to the heat retention combustion operation, A pressure absorbing valve having a structure in which a valve body disposed inside the pressure absorbing valve moves in a direction to expand the volume in the closed conduit and absorbs a pressure increase in the closed conduit. This is the first feature.

The water heater according to the present invention further includes a detecting unit for detecting a displacement of a valve disposed inside the pressure absorbing valve,
A second feature is that a control unit that performs control to stop the warm combustion operation based on the detection signal of the detection unit is provided. A third feature is that while the detection unit is transmitting the detection signal, control is performed to prohibit the insulated combustion operation.

[0007] In the first feature, when the insulated combustion operation is started, water remaining in the closed pipe including the heat exchanger is heated, and the pressure in the closed pipe increases. Due to the structure in which the valve element moves in the direction to expand the volume in the pipe with the increase in pressure, the water remaining in the closed pipe including the heat exchanger is heated during the insulated combustion operation. Even if the pressure in the closed pipe increases, the volume in the pipe can be increased with the increase in the pressure in the pipe, so that a rapid pressure increase can be prevented from acting on the pipe, It is possible to reliably prevent a pipe from being damaged due to repeated stress.

In the second aspect, when the warm combustion operation is started, the water staying in the closed pipe including the heat exchanger is heated, and the pressure in the closed pipe increases. A valve body that moves with the pressure rise and a detection unit for detecting displacement of the valve body are provided in the pressure absorption valve, and when a detection signal of the detection unit is transmitted, the device is held from the closed conduit. By judging that it is just before the water spouts out of the appliance, and by stopping the burner combustion by the insulated combustion operation, it is possible to suppress the pressure increase in the closed pipe, and the number of times the water spouts out of the appliance is reduced. Will be reduced.

In the third aspect, while the detection section is transmitting the detection signal, the control for inhibiting the warming combustion operation is performed. Even if the temperature drop of the water temperature in the pipe is detected due to a temporary decrease and the insulated combustion operation is commanded, it is considered that the pressure in the pipe is in a dangerous state while the detection unit is issuing the detection signal. As a result, warm combustion is not started, so that safer control can be achieved. Also, by not performing unnecessary combustion operation, the durability of parts can be improved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 is an overall configuration diagram showing an embodiment of a water heater with a heat retention function in the present invention, FIG. 2 is a cross-sectional configuration diagram of a pressure absorption valve in the present invention, and FIG. 3 is a cross-sectional structure diagram of a conventional overpressure safety valve.

First, a mechanical embodiment of a water heater with a heat retaining function of the present invention will be described with reference to FIG. This water heater includes a water inlet pipe 1, a tap water pipe 2, a hot water pipe 3, a can body 4 composed of a heat exchanger 5, a burner 6, and a fan 7, and a heat exchanger 5 from the water inlet pipe 1. A bypass pipe 8 directly leading to the tapping pipe 2 without passing through, a bypass flow rate control valve 9 disposed in the bypass pipe 8, a flow rate control valve 12 provided in the hot water supply pipe 3, A hot water supply temperature sensor 13 provided in the hot water supply pipe 3 and bend portions on both sides of a heat exchange pipe constituting the heat exchanger 5 are provided near the heat exchanger 5 and are provided inside the heat exchanger 5. A heat exchanger temperature sensor 14 for detecting the water temperature and the water temperature in the vicinity thereof (hereinafter referred to as the water temperature in the heat exchanger).

A control unit (not shown) controls the operation of the warm-burning operation and also controls various parts of the apparatus required as a water heater. Reference numeral 16 denotes a flame detector, which is located near a part of the combustion tube constituting the burner 6 and detects the presence or absence of a burner flame from the combustion tube. The inlet pipe 1 is provided with a backflow prevention valve 25 for preventing the backflow of high-temperature water generated in the water heater, and a pressure absorption valve 18 is provided in the middle of the hot water pipe 3.

A hot water supply curn 19 is provided at the end of the hot water supply pipe 3. When the hot water supply curan 19 is closed,
That is, when hot water is not supplied, the check valve 2
The hot water supply pipe 1, the heat exchanger 5, the hot water supply pipe 2, and the hot water supply pipe 3 extending to the hot water supply curan 19 downstream of the pipe 5 are closed pipes. Of course, when the bypass pipe 8 is provided in the middle, this bypass pipe 8 also becomes a part of the closed pipe.

The structure of a conventional overpressure safety valve will be described with reference to FIG. This mechanism includes a valve cylinder 40 and a valve port 41.
, A valve element 42, a pressure adjusting lid 43 and a spring 44. The valve body 42 is pressed against the valve seat by the urging force of a spring 44 that can adjust the urging force by tightening the pressure adjusting lid 43 into the valve cylinder 40, and the fluid in the hot water supply conduit is more than the urging force of the spring 44. When the pressure rises, it separates from the valve seat and drains water in the piping to the outside of the device. This prevents an abnormal increase in the pipe internal pressure and prevents the pipe and the heat exchanger from being damaged.

Next, an embodiment of the present invention will be described with reference to FIG. This mechanism includes a valve cylinder 30 and a valve port 31.
, A valve element 32 that receives fluid pressure in the hot-water supply line 3 and slides in the valve cylinder 30, a reed switch 33 attached to the valve port 31, and a magnet 34 provided inside the valve element 32.
And an O-ring 35 for sealing the valve body 32 and the valve cylinder 30
A spring 36 for biasing the valve body 32 in the closing direction;
A pressure adjusting lid 38 is attached to the valve cylinder 30 by a screw and adjusts the urging force of the spring 36. The pressure adjusting lid 38 is provided with a hole 37 for venting air.

The valve body 32 is urged in a direction for closing the hot water supply duct 3 by an urging force of a spring 36 which can be adjusted by tightening the pressure adjusting lid 37 into the valve cylinder 30, and is greater than the urging force of the spring 36. When the fluid pressure in the hot water supply pipe line 3 rises, the sliding movement in the valve cylinder 30 occurs. When the fluid pressure in the hot water supply line 3 rises to a certain level or more and the displacement of the valve element 32 becomes a certain level or more, the distance between the magnet 34 provided in the valve element 32 and the reed switch 33 decreases, and the reed switch 33 is O
N, the detection signal is transmitted to the control unit, so that it is determined that the pressure is just before the pressure at which the retained water is ejected from the closed pipe to the outside of the appliance, and the combustion is stopped if the insulated combustion operation is being performed.

During the warm combustion operation, the control unit includes a heat exchanger 5 detected by the heat exchanger temperature sensor 14.
If the temperature in the inside is equal to or lower than the insulated combustion start temperature TS, the insulated combustion is started, and if the temperature in the heat exchanger 5 is equal to or higher than the insulated combustion end temperature TE, the insulated combustion is ended. However, while the ON signal of the reed switch 33 is being transmitted, even if the temperature detected by the heat exchanger temperature sensor 14 is equal to or lower than the warming combustion start temperature TS, the warming combustion operation is controlled not to be performed. . This prevents the insulated combustion operation from being started due to a partial temperature decrease in the appliance, even though the pressure in the pipe is in a dangerous state, and by not performing useless insulated combustion operation, The purpose is to reduce the number of times of starting and stopping of the combustion part and to consider the durability of parts.

The above embodiment (magnetic field detection system) is merely a preferred embodiment of the present invention. In addition to the above, a contact system based on electrical contact between the valve body and the valve cylinder, and a method provided on the valve cylinder are provided. It is possible to detect the displacement of the valve element by using a displacement sensor such as detection by a mechanical switch such as pressing the switch by the valve element, and to control the warm combustion operation.

[0019]

According to the first aspect of the present invention, there is provided a water supply pipe, a hot water supply pipe, a heat exchanger, and a burner for supplying hot water. A water heater with a heat retention function, wherein the burner burns the burner to perform a warming combustion operation of water in a closed pipe including the heat exchanger. A pressure-absorbing valve that receives a pressure fluid from the pressure introduction passage leading to the valve and releases the pressure by discharging water to the outside when the pressure in the closed conduit rises abnormally. Due to the pressure increase in the closed conduit, the valve element disposed inside the pressure absorbing valve moves in a direction to expand the volume in the closed conduit, and absorbs the pressure increase in the closed conduit. Pressure absorption valve with a structure that Therefore, even if the pressure in the closed pipe increases due to the heating of the water remaining in the closed pipe including the heat exchanger during the insulated combustion operation, the volume in the pipe increases with the increase in the pressure in the pipe. Therefore, it is possible to prevent an abrupt increase in pressure from acting on the pipeline, and it is possible to reliably prevent fatigue damage or the like of the pipeline due to repeated stress. According to the second aspect of the present invention, when the warm combustion operation is started, the water staying in the closed pipe including the heat exchanger is heated, and the pressure in the closed pipe increases. A valve body that moves with this pressure rise and a detection unit for detecting the displacement of the valve body are provided on the pressure absorption valve, and when a detection signal of the detection unit is transmitted, the water contained in the appliance is closed from the closed conduit. Is determined to be the pressure immediately before squirting out of the instrument,
By stopping the combustion of the burner by the insulated combustion operation,
It is possible to suppress an abnormal increase in the pressure in the closed conduit, and it is possible to reduce the number of times of failure such as water spouting out of the appliance. According to the third aspect of the present invention, while the detection unit is transmitting the detection signal, the control is performed such that the warming combustion operation is prohibited. Even when the temperature drop of the water temperature in the pipe is detected due to a significant drop, and the insulated combustion operation is instructed, it is considered that the pressure in the pipe is in a dangerous state while the detection unit is issuing the detection signal. Since safer control can be performed and the number of times of unnecessary combustion is reduced, it is possible to improve the durability of components.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a water heater showing an embodiment of the present invention.

FIG. 2 is a sectional configuration view of a pressure absorption valve according to the present invention.

FIG. 3 is a sectional configuration diagram of a conventional overpressure safety valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inlet line 2 Outlet line 3 Hot water supply line 5 Heat exchanger 6 Burner 18 Pressure absorption valve 19 Hot water supply curan 32 Valve body 33 Reed switch

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsu Kawaguchi 93 Edocho, Chuo-ku, Kobe, Hyogo Prefecture Inside Noritz Co., Ltd. (72) Inventor Hidekazu Fukui 93 Edocho, Chuo-ku, Kobe, Hyogo Noritz Co., Ltd. (72) Inventor Masamitsu Ishizumi, 93 Edo-cho, Chuo-ku, Kobe, Hyogo Prefecture Inside Noritz Co., Ltd. (72) Inventor Takehiro Shimizu 93, Edo-cho, Chuo-ku, Kobe City, Hyogo Prefecture F-term in Noritz Co., Ltd. 3L034 BA22 EA06 3L073 AA02 AA17 AC09 AE01

Claims (3)

[Claims] 1. A water inlet pipe, a hot water supply pipe, a heat exchanger,
Equipped with a burner, even when hot water is not supplied,
By burning the burner, it is a water heater with a heat retaining function capable of performing a warming combustion operation of water in a closed pipe including the heat exchanger, wherein a pressure introduction path leading to the closed pipe. When the pressure fluid is received and the pressure in the closed conduit rises abnormally, the pressure-release valve is provided with a pressure absorption valve that releases the pressure by discharging water to the outside. With a rise in pressure, a valve body disposed inside the pressure absorption valve moves in a direction to expand the volume in the closed conduit, and has a structure to absorb the rise in pressure in the closed conduit. A water heater with a heat retention function, which is provided with a pressure absorption valve. 2. A water heater with a heat retaining function according to claim 1, further comprising a detector for detecting a displacement of a valve element disposed inside the pressure absorbing valve, and performing a warm combustion operation based on a detection signal of the detector. A water heater with a heat retention function, comprising a control unit for performing control to stop the water supply. 3. The water heater with a heat retention function according to claim 2, further comprising a control unit for performing control to inhibit the heat retention combustion operation while the detection signal of the detection unit is being transmitted. Water heater with heat retention function.