JP3754560B2 - Boiler furnace structure - Google Patents

Boiler furnace structure Download PDF

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Publication number
JP3754560B2
JP3754560B2 JP13956198A JP13956198A JP3754560B2 JP 3754560 B2 JP3754560 B2 JP 3754560B2 JP 13956198 A JP13956198 A JP 13956198A JP 13956198 A JP13956198 A JP 13956198A JP 3754560 B2 JP3754560 B2 JP 3754560B2
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Japan
Prior art keywords
furnace
bottom plate
boiler
water
plate
Prior art date
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Expired - Fee Related
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JP13956198A
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Japanese (ja)
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JPH11337001A (en
Inventor
明夫 冨田
聡 柴田
栄治 加来
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Takuma KK
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Takuma KK
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Priority to JP13956198A priority Critical patent/JP3754560B2/en
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Description

【0001】
【発明の属する技術分野】
本発明は、例えば真空式温水機等のボイラの改良に係り、詳しくはこの様なボイラに用いられる火炉構造の改良に関する。
【0002】
【従来の技術】
一般に、真空式温水機等のボイラ(温水ボイラ)としては、例えば図3や図4に示したが知られている。
当該ボイラ50は、上部に蒸気室51が形成されるべく熱媒水52が封入された缶体53と、缶体53の蒸気室51に設けられた温水熱交換器54と、缶体53の熱媒水52に浸漬されて火堰55に依り中心部には燃焼室56がその外周にはガス通路57が形成された火炉58と、上下両端が缶体53の熱媒水54に連通されて火炉58のガス通路57に等間隔毎に配列された多数の水管59と、から構成されている。缶体53は、竪型の円筒状を呈し、外胴60と、これの上部を閉塞する天板61と、外胴60の下部を閉塞する底板62とを備えている。火炉58は、竪型の円筒状を呈し、火炉胴63と、これの上部を閉塞する天板64と、火炉胴63の下部を閉塞する底板65とを備えている。
【0003】
而して、この様なボイラ50に用いられる火炉構造としては、図3に示す如く、天板64と底板65が外側に外突した椀状を呈する椀型と、図4に示す如く、天板64と底板65が平板状を呈する平板型とに大別される。
【0004】
【発明が解決しようとする課題】
然しながら、前者のものは、次の様な問題があった。
(1) 応力の点では形状的に強度があり、板厚も薄くできるメリットがあるものの、原価が高くなる。
(2) 椀部の高さA=200〜300mmが必要となる。火炉では、天板と底板の二箇所に使用するので、400〜600mmの高さが必要となり、火炉の全高が大きくなる。
(3) 椀部のとりわけ水管等を取付ける部分を穴開け加工する場合、三次元レーザがなければ正確な穴が速く加工できず、加工時間が掛かる。
(4) 椀部の溶接や組立に費やす時間も多く掛かり、ロボット等の自動化が難しい。
【0005】
これに対して、後者のものは、前者の前記難点を解消できるものの、次の様な問題があった。
(a) 加工精度に依っては、底板が図4の鎖線で示す如く、内側(上側)に彎曲されて凹部が形成される。そうすると、底板の中央付近で加熱された熱媒水から発生する気泡が溜まり、成長して行って蒸気溜まりとなる。この状態に於て、火炉で加熱が続くと、蒸気溜まりに接している底板が局所加熱されて焼損する。
(b) 応力に対して強度的に弱いので、椀型と同じ強度にするには板厚が数倍厚くなる。
(c) 大型化するには、応力に耐える板厚に限度があり、加工能力や材料費等の点で大型化が難しい。
【0006】
本発明は、叙上の問題に鑑み、これを解消すべく創案されたもので、その課題とする処は、如何なる加工精度に於ても底板の中央部が局所加熱されて熱損するのを防止すると共に、板厚を大きくしないで応力に対する強度を高め、然も大型化が容易に行なえる様にしたボイラの火炉構造を提供することにある。
【0007】
【課題を解決するための手段】
本発明のボイラの火炉構造は、基本的には、火炉を熱媒水の中に浸漬した状態で設けられたボイラに於て、火炉の底板を平板状にしてその中央部のみを下方に突出させて下突部を形成した事に特徴が存する。
【0008】
火炉の底板を平板状にしてその中央部のみを下方に突出させて下突部を形成したので、底板の中央付近に蒸気溜まりができる事がなく、この為、底板の中央部が局所加熱されて焼損する事がない。
【0009】
【発明の実施の形態】
以下、本発明の実施の形態を、図面に基づいて説明する。
図1は、本発明のボイラの火炉構造を示す縦断側面図。図2は、図1の横断平面図である。
【0010】
ボイラ1は、缶体2、温水熱交換器3、火炉4、水管5とからその主要部が構成されて居り、この例では、温水ボイラである真空式温水機にしてある。
【0011】
缶体2は、上部に蒸気室6が形成されるべく熱媒水7が封入されたもので、この例では、竪型の円筒状を呈し、外胴8と、これの上部を閉塞する平板状の天板9と、外胴8の下部を閉塞する平板状の底板10とを備えて架台11の上に立設されて居り、上部に蒸気室(減圧蒸気室)6が形成されるべく熱媒水7が封入されると共に内部が真空に為されている。
【0012】
温水熱交換器3は、缶体2の蒸気室6に設けられたもので、この例では、缶体2内の蒸気室6に配置されて内部に水が流通される様にしてあり、給湯用熱交換器12と暖房用熱交換器13が設けられている。
【0013】
火炉4は、缶体2の熱媒水7に浸漬されて火堰14に依り中心部には燃焼室15がその外周にはガス通路16が形成されたもので、この例では、竪型の円筒状を呈し、缶体2内の熱媒水7に浸漬された状態で配置されて居り、火炉胴17と、これの上部を閉塞する平板状の天板18と、火炉胴17の下部を閉塞する平板状の底板19とを備えている。
而して、火炉4は、火炉胴17の内部に同心状に一側部(図2に於て左側)を欠如して設けられてその内側に燃焼室15を形成すると共にその外側に左右一対のガス通路16を形成し且つ内部が中空で上下両端が熱媒水7に連通された火堰14と、火炉胴17の一側部に燃焼室15と缶体2の外部とを連通すべく設けられたバーナ開口20と、バーナ開口20から挿入されてバーナ火炎21が燃焼室15に位置するバーナ22と、火炉胴17の他側部に各ガス通路16と缶体2の外部とを連通すべく設けられたガス出口23とを備えている。
【0014】
水管5は、上下両端が缶体2の熱媒水7に連通されて火炉4のガス通路16に等間隔毎に配列された多数のもので、この例では、各ガス通路16に15本づつ(合計30本)設けられた左右の水管群を備えている。
【0015】
斯くの如く、ボイラ1は、火炉4を熱媒水7の中に浸漬した状態で設けられている。
而して、火炉4の底板19は、外周部を除く中央部のみがプレス加工に依り下方に突出されて椀状を呈する下突部24が形成されている。
火炉4の火堰14と水管5は、火炉4の底板19の平板状の外周部に貫通して設けられている。
【0016】
次に、この様な構成に基づいて作用を述解する。
バーナ22に依り火炉4の燃焼室15で燃料が燃焼されると、燃焼ガスが左右に分流されて各ガス通路16を通過した後、合流されてガス出口23から缶体2の外部に排出される。そうすると、缶体2内の熱媒水7が加熱されて蒸発気化され、水蒸気となって上昇されて蒸気室6に至り、水蒸気が温水熱交換器3に放熱して液化される。温水熱交換器3の表面で液化された熱媒水7は、下方に流下される。そして、温水熱交換器3は、水蒸気の相変化に依る潜熱に依り加熱され、これに依り温水熱交換器3内を流れる水が加熱され、給湯や暖房の為に送り出される。
【0017】
缶体2と火炉4との間が真空であるので、火炉4の全体が外側に向けて引っ張られる状態になる。火炉4の底板19が平板状であれば、その応力がそのまま掛かるが、その中央部には下突部24が形成してあるので、その部分の強度が増し、補強材を使用しなくても応力に耐えられる。
火炉4の底板19の中央部には下突部24が形成されているので、蒸気溜まりができず、この為に火炉4内の燃焼に依る局所加熱が起こらず、その結果、同部分の焼損が防止できる。
火炉4の底板19は、中央部を除いて平板状を呈するので、火堰14や水管5等の穴開け加工が極めて容易になると共に、ボイラの組立がやり易くなって組立工数も大幅に削減され、自動化も容易に行なえる。
【0018】
火炉4の底板19を平板状にしてその中央部のみを下方に突出させて下突部24を形成したので、平板型に比べて原価が少し上昇するものの、椀型に比べて二分の一以下となり、コストの低減を図る事ができる。
【0019】
尚、火炉構造は、先の例では、真空式温水機に適用したが、これに限らず、例えばこれ以外のボイラに適用しても良い。
下突部24は、先の例では、椀状であったが、これに限らず、例えば円錐状等でも良い。
【0020】
【発明の効果】
以上、既述した如く、本発明に依れば、次の様な優れた効果を奏する事ができる。
(1) 火炉を熱媒水の中に浸漬した状態で設けられたボイラに於て、火炉の底板を平板状にしてその中央部のみを下方に突出させて下突部を形成したので、如何なる加工精度に於ても底板の中央部が局所加熱されて熱損するのを防止する事ができる。
(2) 火炉の底板を平板状にしてその中央部のみを下方に突出させて下突部を形成したので、板厚を大きくしないで応力に対する強度を高める事ができる。
(3) 板厚を大きくしないで応力に対する強度を高める事ができるので、大型化が容易に行なえる。
【図面の簡単な説明】
【図1】本発明のボイラの火炉構造を示す縦断側面図。
【図2】図1の横断平面図。
【図3】従来の椀型の火炉構造を示す縦断側面図。
【図4】従来の平板型の火炉構造を示す縦断側面図。
【符号の説明】
1,50…ボイラ、2,53…缶体、3,54…温水熱交換器、4,58…火炉、5,59…水管、6,51…蒸発室、7,52…熱媒水、8,60…外胴、9,18,61,64…天板、10,19,62,65…底板、11…架台、12…給湯用熱交換器、13…暖房用熱交換器、14,55…火堰、15,56…燃焼室、16,57…ガス通路、17,63…火炉胴、20…バーナ開口、21…バーナ火炎、22…バーナ、23…ガス出口、24…下突部、A…椀部の高さ。
[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a boiler such as a vacuum hot water machine, and more particularly to an improvement in a furnace structure used in such a boiler.
[0002]
[Prior art]
Generally, as a boiler (hot water boiler) such as a vacuum hot water machine, for example, as shown in FIGS. 3 and 4 is known.
The boiler 50 includes a can body 53 in which heat medium water 52 is sealed so that a steam chamber 51 is formed at an upper portion, a hot water heat exchanger 54 provided in the steam chamber 51 of the can body 53, A combustion chamber 56 is immersed in the heat transfer water 52 by a fire weir 55 and a furnace 58 in which a gas passage 57 is formed in the outer periphery thereof, and both upper and lower ends communicate with the heat transfer water 54 of the can body 53. And a large number of water pipes 59 arranged at equal intervals in the gas passage 57 of the furnace 58. The can 53 has a bowl-shaped cylindrical shape, and includes an outer body 60, a top plate 61 that closes an upper portion of the outer body 60, and a bottom plate 62 that closes a lower portion of the outer body 60. The furnace 58 has a bowl-shaped cylindrical shape, and includes a furnace body 63, a top plate 64 that closes an upper portion of the furnace body 63, and a bottom plate 65 that closes a lower portion of the furnace body 63.
[0003]
Thus, as a furnace structure used in such a boiler 50, as shown in FIG. 3, a bowl shape having a bowl shape in which a top plate 64 and a bottom plate 65 project outward, and a ceiling plate as shown in FIG. The plate 64 and the bottom plate 65 are roughly divided into flat plate types having a flat plate shape.
[0004]
[Problems to be solved by the invention]
However, the former had the following problems.
(1) In terms of stress, there is strength in shape and there is an advantage that the plate thickness can be reduced, but the cost is increased.
(2) The height A of the buttock is required to be 200 to 300 mm. Since the furnace is used in two places, the top plate and the bottom plate, a height of 400 to 600 mm is required, and the total height of the furnace is increased.
(3) When drilling a part of the buttock, particularly a water pipe, an accurate hole cannot be processed quickly without a three-dimensional laser, and processing time is required.
(4) It takes a lot of time to weld and assemble the buttocks, making it difficult to automate robots.
[0005]
On the other hand, although the latter can solve the above-mentioned difficulties, there are the following problems.
(A) Depending on the processing accuracy, the bottom plate is bent inward (upper side) to form a recess as shown by the chain line in FIG. If it does so, the bubble which generate | occur | produces from the heat-medium water heated in the center vicinity of the bottom plate will accumulate, it will grow, and it will become a vapor reservoir. In this state, when heating continues in the furnace, the bottom plate in contact with the steam pool is locally heated and burns out.
(B) Since the strength is weak against stress, the thickness of the plate becomes several times thicker in order to obtain the same strength as the saddle type.
(C) In order to increase the size, there is a limit to the plate thickness that can withstand stress, and it is difficult to increase the size in terms of processing capability and material costs.
[0006]
The present invention has been devised in view of the above-mentioned problems, and has been devised to solve this problem. The problem is to prevent the central portion of the bottom plate from being locally heated at any processing accuracy and causing heat loss. Another object of the present invention is to provide a boiler furnace structure that can increase the strength against stress without increasing the plate thickness and can be easily increased in size.
[0007]
[Means for Solving the Problems]
The furnace structure of the boiler of the present invention is basically a boiler provided with the furnace immersed in heat transfer water, and the bottom plate of the furnace is formed into a flat plate shape and only its central portion projects downward. The feature is that the lower protrusion was formed.
[0008]
Since the bottom plate of the furnace is made flat and only the center part protrudes downward to form the lower protrusion, there is no possibility of steam accumulation near the center of the bottom plate, so the center part of the bottom plate is locally heated. It will not burn out.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal side view showing a furnace structure of a boiler according to the present invention. FIG. 2 is a cross-sectional plan view of FIG.
[0010]
The boiler 1 is composed mainly of a can body 2, a hot water heat exchanger 3, a furnace 4, and a water pipe 5. In this example, the boiler 1 is a vacuum water heater that is a hot water boiler.
[0011]
The can body 2 is filled with a heat transfer water 7 so that a steam chamber 6 is formed at the upper portion. In this example, the can body 2 has a bowl-shaped cylindrical shape, and a flat plate that closes the outer body 8 and the upper portion thereof. A top plate 9 and a flat bottom plate 10 for closing the lower part of the outer body 8 are provided on a stand 11 so that a steam chamber (decompressed steam chamber) 6 is formed on the upper part. The heat transfer water 7 is enclosed and the inside is evacuated.
[0012]
The hot water heat exchanger 3 is provided in the steam chamber 6 of the can body 2. In this example, the hot water heat exchanger 3 is disposed in the steam chamber 6 in the can body 2 so that water is circulated therein. A heat exchanger 12 for heating and a heat exchanger 13 for heating are provided.
[0013]
The furnace 4 is immersed in the heat transfer water 7 of the can body 2 and has a combustion chamber 15 formed in the center thereof by a fire weir 14 and a gas passage 16 formed in the outer periphery thereof. It has a cylindrical shape and is disposed so as to be immersed in the heat transfer water 7 in the can body 2. The furnace body 17, the flat top plate 18 that closes the upper part thereof, and the lower part of the furnace body 17 are arranged. And a flat bottom plate 19 to be closed.
Thus, the furnace 4 is provided concentrically inside the furnace body 17 without one side (left side in FIG. 2) to form a combustion chamber 15 on the inside and a pair of left and right sides on the outside. In order to communicate between the combustion chamber 15 and the outside of the can body 2 at one side of the furnace body 17 and a gas weir 14 having a gas passage 16 formed therein and hollow inside and communicated with the heat transfer water 7 at both upper and lower ends. The provided burner opening 20, the burner 22 inserted from the burner opening 20 so that the burner flame 21 is located in the combustion chamber 15, and the gas passages 16 and the outside of the can 2 are connected to the other side of the furnace body 17. And a gas outlet 23 provided to pass therethrough.
[0014]
The upper and lower ends of the water pipe 5 communicate with the heat transfer water 7 of the can body 2 and are arranged at equal intervals in the gas passage 16 of the furnace 4. In this example, 15 water pipes 5 are provided for each gas passage 16. (Total 30) The left and right water tube groups are provided.
[0015]
As described above, the boiler 1 is provided in a state in which the furnace 4 is immersed in the heat transfer water 7.
Thus, the bottom plate 19 of the furnace 4 is formed with a lower protrusion 24 having a bowl-like shape that protrudes downward only by a pressing process except for the outer peripheral portion.
The fire weir 14 and the water pipe 5 of the furnace 4 are provided so as to penetrate the flat plate-like outer peripheral portion of the bottom plate 19 of the furnace 4.
[0016]
Next, the operation will be described based on such a configuration.
When the fuel is combusted in the combustion chamber 15 of the furnace 4 by the burner 22, the combustion gas is diverted to the left and right, passes through each gas passage 16, merges, and is discharged from the gas outlet 23 to the outside of the can 2. The Then, the heat transfer water 7 in the can body 2 is heated and evaporated to be vaporized to rise to the vapor chamber 6, and the vapor is radiated to the hot water heat exchanger 3 and liquefied. The heat transfer water 7 liquefied on the surface of the hot water heat exchanger 3 flows down. The hot water heat exchanger 3 is heated by the latent heat due to the phase change of water vapor, and the water flowing in the hot water heat exchanger 3 is heated by this, and sent out for hot water supply or heating.
[0017]
Since the space between the can 2 and the furnace 4 is a vacuum, the entire furnace 4 is pulled outward. If the bottom plate 19 of the furnace 4 is flat, the stress is applied as it is, but since the lower protrusion 24 is formed at the center, the strength of that portion is increased, and a reinforcing material is not used. Can withstand stress.
Since the lower protrusion 24 is formed in the center portion of the bottom plate 19 of the furnace 4, steam cannot be accumulated, and local heating due to combustion in the furnace 4 does not occur. As a result, the same portion is burned out. Can be prevented.
Since the bottom plate 19 of the furnace 4 has a flat shape except for the central portion, drilling of the fire weir 14 and the water pipe 5 is extremely easy, and the assembly of the boiler is facilitated and the number of assembly steps is greatly reduced. It is easy to automate.
[0018]
Since the bottom plate 19 of the furnace 4 is formed in a flat plate shape and only the central portion thereof protrudes downward to form the lower protrusion 24, the cost is slightly increased compared to the flat plate type, but less than half of the vertical type. Thus, the cost can be reduced.
[0019]
In addition, although the furnace structure was applied to the vacuum hot water machine in the previous example, it is not limited thereto, and may be applied to other boilers, for example.
In the above example, the lower protrusion 24 has a bowl shape, but is not limited thereto, and may have a conical shape, for example.
[0020]
【The invention's effect】
As described above, according to the present invention, the following excellent effects can be obtained.
(1) In the boiler provided with the furnace immersed in the heat transfer water, the bottom plate of the furnace is made flat and only the center part protrudes downward to form the lower protrusion. Even in the processing accuracy, it is possible to prevent the central portion of the bottom plate from being locally heated and causing heat loss.
(2) Since the bottom plate of the furnace is made flat and only the central portion protrudes downward to form the lower protrusion, the strength against stress can be increased without increasing the plate thickness.
(3) Since the strength against stress can be increased without increasing the plate thickness, the size can be easily increased.
[Brief description of the drawings]
FIG. 1 is a longitudinal side view showing a furnace structure of a boiler according to the present invention.
FIG. 2 is a cross-sectional plan view of FIG.
FIG. 3 is a longitudinal side view showing a conventional vertical furnace structure.
FIG. 4 is a longitudinal side view showing a conventional flat-plate furnace structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,50 ... Boiler, 2,53 ... Can body, 3,54 ... Hot water heat exchanger, 4,58 ... Furnace, 5,59 ... Water pipe, 6,51 ... Evaporation chamber, 7,52 ... Heat transfer water, 8 , 60 ... outer trunk, 9, 18, 61, 64 ... top plate, 10, 19, 62, 65 ... bottom plate, 11 ... mount, 12 ... heat exchanger for hot water supply, 13 ... heat exchanger for heating, 14, 55 ... fire weir, 15, 56 ... combustion chamber, 16, 57 ... gas passage, 17, 63 ... furnace shell, 20 ... burner opening, 21 ... burner flame, 22 ... burner, 23 ... gas outlet, 24 ... bottom projection, A ... Height of the buttocks.

Claims (1)

火炉を熱媒水の中に浸漬した状態で設けられたボイラに於て、火炉の底板を平板状にしてその中央部のみを下方に突出させて下突部を形成した事を特徴とするボイラの火炉構造。In a boiler provided with the furnace immersed in heat transfer water, the bottom plate of the furnace is formed into a flat plate shape, and only the central portion protrudes downward to form a lower protrusion. Furnace structure.
JP13956198A 1998-05-21 1998-05-21 Boiler furnace structure Expired - Fee Related JP3754560B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13956198A JP3754560B2 (en) 1998-05-21 1998-05-21 Boiler furnace structure

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13956198A JP3754560B2 (en) 1998-05-21 1998-05-21 Boiler furnace structure

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JPH11337001A JPH11337001A (en) 1999-12-10
JP3754560B2 true JP3754560B2 (en) 2006-03-15

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Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5247382B2 (en) * 2008-11-28 2013-07-24 西松建設株式会社 Heating and hot water supply system, energy saving and greenhouse gas emission reduction method
JP5604267B2 (en) * 2010-11-08 2014-10-08 株式会社日本サーモエナー Heat recovery apparatus for exhaust gas from vacuum hot water machine and heat recovery method using the same
JP5604268B2 (en) * 2010-11-08 2014-10-08 株式会社日本サーモエナー Heat recovery apparatus for exhaust gas from vacuum hot water machine and heat recovery method using the same

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