JPH068442Y2 - Decompression type water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a decompression type water heater, more specifically, a heat exchanger is arranged in a sealed decompression steam chamber so that hot water can be efficiently obtained. The present invention relates to a water heater.

[Conventional technology]

There is already known a water heating device that decompresses the inside of the steam chamber and uses the heat exchanger placed in this steam chamber to obtain hot water. In addition, since the heating uses condensation heat transfer of steam, the heat exchange efficiency is extremely good. Furthermore, the structure is simple and the manufacturing cost is low, and the device is always in a depressurized state (below atmospheric pressure). ), There is no danger.

By the way, in the conventional depressurization type water heater, a combustion chamber surrounded by a water jacket is provided in the lower part of the decompression steam room, and a steam generating tube with fins is installed so that both ends communicate with the inside of the water jacket. The steam generation pipes are arranged in an inclined shape so that the heating medium liquid is filled up to the water level covering the ceiling of the combustion chamber and the heated heating medium liquid circulates smoothly.

In the decompression type water heater as described above, when the burner is ignited to heat the steam generation tube in a state where the temperature of the heat transfer medium is low, the heat transfer medium in the steam generation tube immediately starts boiling because it is in a depressurized state. Generates steam.

[Problems to be solved by the device]

These vapor bubbles try to come out to the steam chamber through the heat transfer liquid in the water jacket, but since the heat transfer liquid in the water jacket is still low in temperature, the bubbles rapidly cool and shrink here, causing a burst. However, there is a problem that a loud noise is generated.

Further, since the heating medium liquid is filled up to the water level covering the ceiling of the combustion chamber, there is a drawback that the amount of liquid increases and it takes a long time until the temperature of the entire heating medium liquid rises to a normal boiling state. is there.

Therefore, the problem of the present invention is to solve the above problems, so that the generation of sound immediately after ignition is extremely small,
Another object of the present invention is to provide a decompression-type water heater capable of shortening the rise time until reaching a normal state and improving the overall efficiency.

[Means for Solving the Problems]

In order to solve the above problems, the present invention provides a water jacket surrounding the combustion chamber on the outside of the combustion chamber having a burner,
A depressurized steam chamber that is connected to the upper part of the water jacket and covers the upper part of the combustion chamber is provided in a sealed state, a hot water supply heat exchanger is housed inside the depressurized steam chamber, and a hollow internal steam generation tube Are installed horizontally so that both ends communicate with the inside of the water jacket at positions opposite to each other, and the width of the portion of the water jacket where the steam generation pipe opens is wider than other positions so as to serve as a passage for the generated steam. And a storage part for the heat transfer liquid is formed on the upper surface of the combustion chamber facing the reduced pressure vapor chamber, and an exhaust stack rising from this combustion chamber penetrates the reduced pressure vapor chamber in an airtight manner and draws it out to the outside. The heat exchanger incorporated in the steam chamber is arranged so as to be sandwiched between the peripheral wall of the reduced pressure steam chamber and the facing surface of the exhaust pipe.

[Action]

When the heat transfer fluid for the water jacket and steam generation tube is filled to a water level that fills the lower half of the steam generation tube and the burner is ignited in the combustion chamber, the heat transfer fluid heated via the steam generation tube enters the decompression steam chamber. The vapor that has evaporated and generated in the upper half of the steam generation tube can be sent to the decompression steam chamber without hiding the heat transfer liquid. Hot water is obtained by exchanging heat with steam in an exchanger.

〔Example〕

An embodiment of the present invention will be described below with reference to the accompanying drawings.

In the first embodiment shown in FIGS. 1 to 3, a water heater comprises a frame-shaped water jacket 2 surrounding the combustion chamber 1 on the outside of the combustion chamber 1 having a burner 16, and this water jacket 2 And a decompression steam chamber 3 which covers the upper part of the combustion chamber 1 in a continuous manner and is installed in the combustion chamber 1 in a state where an internal hollow steam generation pipe 4 is connected to the water can 2 and An exhaust pipe 5 connected to the upper part of 1 penetrates the inside of the reduced pressure steam chamber 3 in an airtight manner and projects to the outside of the upper part, and heat exchangers 6 and 7 are incorporated in the reduced pressure steam chamber 3.

The steam generation pipe 4 provided in the combustion chamber 1 is horizontally arranged so as to communicate with each other at opposite sides of the water canister 2 and has a structure in which a large number of fins 8 on the outer peripheral surface thereof are attached. Two pieces are arranged side by side, but the number can be freely increased or decreased.

The lower end of the exhaust pipe 5 is connected to the central portion of the ceiling plate 9 in the combustion chamber 1, and a low rising wall 10 is provided around the ceiling plate 9, and the rising wall 10 allows the shallow heat medium liquid pool to be formed on the ceiling plate 9. 11 is formed.

As shown in FIG. 1, the heat transfer medium A is poured into the water jacket 2 and the steam generation pipe 4 to a water level that fills the lower half of the steam generation pipe 4, and the upper half of the steam generation pipe 4 is filled. Is used as the passage 12 for the generated steam.

In order that the steam generated in the passage 12 of the steam generating tube 4 can be smoothly ejected to the depressurized steam chamber 3, the two surface portions of the water jacket 2 where the ends of the steam generating tube 4 are open are shown in FIGS. As is clear from the figure, it is formed wider than the other two surface portions, and at the same time, the amount of the heat transfer liquid is reduced.

In addition, for example, one of the heat exchangers 6 and 7 incorporated in the reduced pressure steam chamber 3 is used for a bath and the other is used for hot water supply, and an extraction valve 13 and a fusible plug 14 are provided on the upper portion of the reduced pressure steam chamber 3.
Is installed.

The reduced pressure steam chamber 3 and an exhaust pipe 5 penetrating the inside thereof
In order to prevent deformation of the peripheral wall due to decompression, the exhaust pipe 5 is separated into two, and the upper wall 15 of the steam chamber 3 and the ceiling plate 9 of the combustion chamber 1 are joined by welding via the exhaust pipe 5. In addition, as shown in FIG. 3, the heat exchangers 6 and 7 have a straight line in the longitudinal direction passing through the side wall of the steam chamber 3 and the side wall of the exhaust pipe 5 and between the exhaust pipes 5 as shown in FIG. The steam chamber 3 and the exhaust pipe 5 are assembled so that both ends in the longitudinal direction abut on the side wall of the steam chamber 3.
By supporting the side walls of the heat exchangers 6 and 7, the deformation resistance strength is improved. The drawings show heat exchangers 6 and 7.
A gap was provided between each other and between the reduced pressure steam chamber 3 and the exhaust pipe 5 to facilitate understanding, but in reality, they are arranged so that they are in contact with each other, or spacers are inserted so that they are in contact with each gap. Is.

The first embodiment of the present invention has the above-described structure, and the heat transfer medium A is injected to fill the lower half of the steam generating pipe 4 as shown in FIG. When the burner 16 is ignited to heat the steam generation tube 4 in a reduced pressure state,
The generated steam immediately passes through the passage 12 to the water jackets 2 at both ends.

Since there is no heat transfer liquid in the upper part of the water jacket 2, the steam blows out into the decompression steam chamber 3 without submerging the heat transfer liquid, and no sound is generated due to the burst of the steam bubbles.

In the depressurized steam chamber 3, the steam adheres to the outer peripheral surfaces of the heat exchangers 6 and 7, heat-exchanges with the water flowing in the heat exchangers to heat them, and the condensed water droplets are accumulated in the heat medium liquid pool 11 immediately below. It falls and overflows this heat medium liquid pool 11
Return to inside.

By the way, if the heat medium liquid is reduced to a level that fills the lower half of the steam generation tube 4 and the water level is lowered, the time required for the entire body to reach a normal boiling state can be greatly shortened. Since the upper part of the peripheral wall of the chamber 1 is exposed to the combustion gas, there is a fear that it will be in a so-called empty state.

However, in this invention, since the heating medium liquid pool 11 is provided on the upper surface of the ceiling plate 9 in the combustion chamber 1, the overflowing heating medium liquid always makes the wall surface of the combustion chamber 1 wet, which causes abnormal heating. It is preventing.

Next, a second embodiment shown in FIG. 4 and FIG. 5 shows a different built-in structure of the heat exchangers 6 and 7 with respect to the inside of the reduced pressure steam chamber 3, using one exhaust pipe 5, Heat exchangers 6 and 7
Is a combination of a large-diameter spiral and a small-diameter spiral inside and outside, and a parallel straight line portion is interposed between the steam chamber 3 and the exhaust pipe 5 to prevent deformation of the steam chamber 3 and the exhaust pipe 5 due to depressurization. is there.

〔effect〕

As described above, according to the present invention, since the configuration is as described above, there are the effects listed below.

(I) Steam generated in the steam generation tube by injecting a heat medium liquid in an amount satisfying the lower half of the steam generation tube provided in the combustion chamber and using the upper half of the steam generation tube as a passage for the generated steam. Can be jetted into the depressurized steam chamber without submerging in the heat transfer liquid, and noise due to burst of steam bubbles is eliminated.

(II) Since it is sufficient to fill the lower half of the steam generation tube with the heat transfer fluid, the amount of heat transfer fluid can be reduced, and the time required for the whole to reach a normal boiling state can be greatly shortened. The cost can be reduced.

(III) Since the exhaust stack connected to the combustion chamber penetrates the reduced pressure steam chamber, the inside of the steam chamber is always maintained at atmospheric pressure or lower, and the boiling temperature, that is, the steam temperature is 100 ° C. or lower, but the exhaust gas temperature is Since it is always higher than this, heat exchange can be performed between the exhaust gas and the steam, and heat recovery can be improved.

(IV) Since the heating medium liquid pool is provided on the ceiling of the combustion chamber, the heating medium liquid also evaporates in this part, and the overflowing heating medium liquid wets the peripheral wall of the combustion chamber, which causes abnormal heating. It is possible to prevent damage from occurring and improve durability.

(V) If the width of the water jacket is narrow at the portion where the end of the steam generating tube is open, the steam velocity passing through the steam generating tube becomes high and water droplets are entrained, and water droplets are applied to the heat exchanger in the steam chamber. Although the heat transfer of condensation due to the steam is blocked, the gap between the water jackets on the two sides where the steam generation pipe is opened is wide, so there is no fear of this. Since the gap is narrowed, the total amount of liquid can be reduced.

(VI) If a heat exchanger is installed so that the exhaust stack penetrates the decompression steam chamber and is in contact with the exhaust stack and the decompression steam chamber, the heat exchanger prevents distortion due to decompression of the decompression steam chamber and the exhaust stack. can do.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional front view showing a first embodiment of a water heater according to the present invention, FIG. 2 is a longitudinal side view of the same, FIG. 3 is a transverse plan view of the same, and FIG. 4 is a second embodiment thereof. FIG. 5 is a cross-sectional plan view of the same as above. 1 ... Combustion chamber, 2 ... Water jacket, 3 ... Decompression steam chamber, 4 ... Steam generation tube, 5 ... Exhaust pipe, 6, 7 ... Heat exchanger, 11 ... Heat medium liquid pool, 12 ……aisle.

Claims (1)

[Scope of utility model registration request] 1. A decompression steam is provided outside a combustion chamber having a burner in a hermetically sealed state, with a water jacket surrounding the combustion chamber and a decompression steam chamber continuous with the upper part of the water jacket and covering the upper part of the combustion chamber. A heat exchanger for hot water supply is stored inside the chamber, and in the combustion chamber,
In order to use the inner hollow steam generating pipe horizontally so that the both ends communicate with the inside of the water jacket at positions opposite to each other, the width of the portion of the water jacket where the steam generating pipe opens is used as a passage for the generated steam. Formed wider than other positions, forming a heat medium liquid storage portion on the upper surface of the combustion chamber facing the depressurized vapor chamber, and an exhaust stack rising from this combustion chamber penetrates the depressurized vapor chamber in an airtight manner. A decompression-type water heater in which a heat exchanger that is drawn out to the outside and is incorporated in the decompression steam chamber is arranged so as to be sandwiched between the peripheral wall of the decompression steam chamber and the facing surface of the exhaust pipe.