JPS58103795A - Hot water heater - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 本発明は給湯用、暖房用などに用いられる温水加熱装置
に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hot water heating device used for hot water supply, space heating, etc.

従来の温水加熱装置は第９図および第１０図に示すよう
に、一端を冷水路と接続する流入口３１とした円筒状の
面発熱体３２と、この円筒状の面発熱体３２の外周との
間に加熱流路３３を形成する外ケース３４とにより構成
されている。前記外ケース３４には、面発熱体３２の流
入口３１側に位置して流出路３６を設けている。また前
記円筒状の面発熱体３２は円筒状のセラミック材からな
る基体Ａ３６と、シート状セラミック材から々る基体Ｂ
３７とで発熱抵抗体３８を挾持して構成している。そし
て前記基体に３６は、成形時の歪みを小さく押さえ、か
つ円筒状の面発熱体３２の機械的強度を保持するために
、所定の厚みｔｌを必要とし、また基体Ｂ３７は基体ム
３６の外周に口ＩＪソングるため、その作業が良好に行
えるように、基体Ａ３６の厚みｔｌに比べ、非常に小さ
な厚みｔ２で構成されている。As shown in FIGS. 9 and 10, the conventional hot water heating device includes a cylindrical surface heating element 32 having one end as an inlet 31 connected to a cold waterway, and an outer periphery of this cylindrical surface heating element 32. and an outer case 34 forming a heating flow path 33 therebetween. The outer case 34 is provided with an outlet passage 36 located on the inlet 31 side of the surface heating element 32. The cylindrical surface heating element 32 has a base A36 made of a cylindrical ceramic material, and a base B made of a sheet-like ceramic material.
37 and a heating resistor 38 sandwiched therebetween. The base body 36 requires a predetermined thickness tl in order to suppress distortion during molding and maintain the mechanical strength of the cylindrical surface heating element 32, and the base body B37 requires a predetermined thickness tl on the outer periphery of the base body 36. The base body A36 has a thickness t2 that is very small compared to the thickness t1 of the base body A36 so that the work can be carried out smoothly.

上記従来の構成において、流入口３１から流入した冷水
は、円筒状の面発熱体３２の内管路３２′で加熱されな
がら左端開放部に達し、その後、加熱流路３３に流入し
てさらに加熱され、流出路３５より温水となって流出す
る。In the above conventional configuration, the cold water flowing in from the inlet 31 reaches the open left end portion while being heated by the inner pipe 32' of the cylindrical surface heating element 32, and then flows into the heating flow path 33 where it is further heated. The hot water flows out from the outflow path 35 as hot water.

上記加熱工程において、円筒状の面発熱体３２の表面温
度は、セラミック基体ム３６　、Ｂ３７の厚みｔＩ　、
　ｔ、、と前記円筒状の面発熱体３２０表面における水
への熱伝達率との関係により決まる。In the above heating step, the surface temperature of the cylindrical surface heating element 32 is determined by the thickness tI of the ceramic base 36, B37,
It is determined by the relationship between t and the heat transfer coefficient to water on the surface of the cylindrical surface heating element 320.

上記従来例においては、円筒状の面発熱体３２における
内管路３２′の流速は、加熱流路３３の流用面の水への
熱伝達率は外周面の熱伝達率より大きく々る。一方、円
筒状の面発熱体３２の内周面側基体Ａ３６の厚みｔｌは
外周面側基体Ｂ３７の厚みｔ２に比べて大きい。従って
、発熱抵抗体３８から円筒状の面発熱体３２の内周面へ
の伝熱抵抗は外周面への伝熱抵抗より大きい。その結果
、円筒状の面発熱体３２の内周面は、水への熱伝達率が
大きいのに対し、発熱抵抗体３８からの伝熱抵抗が太き
いため、その表面温度は第１１図のＴｓｌで示すように
低下する。また円筒状の面発熱体３２の外周面は、水へ
の熱伝達率が小さいのに対し、発熱抵抗体３８からの伝
熱抵抗が小さいため、その表面温度は第１１図の’Ｉ’
ｓｏで示すように、高くなる。In the above-mentioned conventional example, the flow rate in the inner pipe 32' of the cylindrical surface heating element 32 is such that the heat transfer coefficient to water on the flow surface of the heating flow path 33 is greater than the heat transfer coefficient on the outer circumferential surface. On the other hand, the thickness tl of the inner peripheral surface side base body A36 of the cylindrical surface heating element 32 is larger than the thickness t2 of the outer peripheral surface side base body B37. Therefore, the heat transfer resistance from the heating resistor 38 to the inner circumferential surface of the cylindrical surface heating element 32 is greater than the heat transfer resistance to the outer circumferential surface. As a result, the inner circumferential surface of the cylindrical surface heating element 32 has a large heat transfer coefficient to water, but the heat transfer resistance from the heating resistor 38 is large, so that the surface temperature is as shown in FIG. It decreases as shown by Tsl. Further, the outer circumferential surface of the cylindrical surface heating element 32 has a small heat transfer coefficient to water, but the heat transfer resistance from the heating resistor 38 is small, so the surface temperature is 'I' in FIG.
As shown by so, it becomes high.

以上のように従来の温水加熱装置においては、円筒状の
面発熱体３２の内周面、外周面上での表面温度差が非常
に太きいため、熱交換状態にアンバランスを生じ、その
結果、発熱体の全表面が熱交換に対し有効に生かされず
、熱交換効率が低下する。As described above, in the conventional hot water heating device, the difference in surface temperature between the inner circumferential surface and the outer circumferential surface of the cylindrical surface heating element 32 is very large, resulting in an imbalance in the heat exchange state. , the entire surface of the heating element is not effectively utilized for heat exchange, resulting in a decrease in heat exchange efficiency.

また前記面発熱体３２の外周面は高温に々す、局部的な
核沸騰を起こし、スケールの主成分である重炭酸カルシ
ウム、重炭酸マグネシウムの飽和溶解度を示す温度以上
となり、スケールが面発熱体３２の表面に析出する。第
１２図は重炭酸カルシウムのＰＨと温度と溶解度の関係
を示したものである。そしてこのスケールは面発熱体３
２０表面で徐々に厚みを増し、発熱抵抗体３８から面発
熱体３２の表面への熱伝達を悪化させ、熱交換効率を下
げるとともに、発熱抵抗体３８の温度を異常に高めてし
まうため、発熱抵抗体３８を断線させてしまうという欠
点を有していた。In addition, the outer peripheral surface of the surface heating element 32 reaches a high temperature, causing local nucleate boiling, and the temperature reaches a temperature higher than the saturated solubility of calcium bicarbonate and magnesium bicarbonate, which are the main components of scale, and the scale becomes the surface heating element 32. Precipitates on the surface of 32. FIG. 12 shows the relationship between pH, temperature, and solubility of calcium bicarbonate. And this scale is surface heating element 3
The thickness gradually increases on the surface of the heating resistor 38, worsening the heat transfer from the heating resistor 38 to the surface of the surface heating element 32, lowering the heat exchange efficiency, and abnormally increasing the temperature of the heating resistor 38, which causes heat generation. This has the drawback of causing the resistor 38 to become disconnected.

本発明は、上記従来の欠点に鑑み、２つのセラミック基
体で発熱抵抗体を挾持して構成した発熱素子と、この発
熱素子の両側面に設けられ、一方は流体流入口と連通し
、かつ他方は流体流出口と連通ずる流通路とを備え、前
記発熱抵抗体から各セラミック基体への熱伝達量を、前
記発熱素子の両側面表面平均温度が略等しくなるように
構成する手段を設けることにより、前記発熱素子の表面
平均温度をスケール生成温度以下に制御または保持する
ことを容易にするとともに、熱交換効率を高めることが
できる温水加熱装置を提供しようとするものである。In view of the above conventional drawbacks, the present invention provides a heating element configured by sandwiching a heating resistor between two ceramic substrates, and a heating element provided on both sides of the heating element, one communicating with a fluid inlet and the other. is provided with a flow path communicating with a fluid outlet, and by providing means for configuring the amount of heat transferred from the heat generating resistor to each ceramic base so that the average temperature of both side surfaces of the heat generating element is approximately equal. An object of the present invention is to provide a hot water heating device that can easily control or maintain the surface average temperature of the heating element below the scale formation temperature and can improve heat exchange efficiency.

以下、本発明の一実施例について、第１図〜第４図にも
とづいて説明する。第１図、第２図において、１は円筒
状に構成された発熱素子で、この発熱素子１はセラミッ
ク基体Ａ２とセラミック基体Ｂ３とで発熱抵抗体４を挾
持することにより構成している。そして前記セラミック
基体Ａ２は、成形時の歪みを極力小さく押さえ、かつ発
熱素子１の機械的強度を保持するため所定の厚みｔＡを
必要とし、またセラミック基体Ｂ３はセラミック基体Ａ
２の外周にローリングするため、セラミック基体ム２の
厚みｔＡに比べ非常に小さな厚みｔＢで構成されている
。また円筒状に構成された発熱素子１は内管路５を有す
るとともに、一端には、冷水供給管への接続ねじ６を取
付けた流体流入ロアを内管路６と連通するように設けて
いる。８は外ケースで、この外ケース８は発熱素子１０
列周との間に加熱流路９を形成し、かつ前記発熱素子１
の内管路６の他端側を閉塞し、さらに前記流体流入ロア
側に位置して流体流出口１０を設けている。前記加熱流
路ｅ内には、被加熱流体に旋回流を与えて加熱流路９内
における加熱流体の流速を高めるため、螺旋状のインナ
ーフィン１１を挿入している。１２１Ｌは発熱抵抗体４
への通電用リード線、１２ｂは制御部、１２０はセンサ
ーである。Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 4. In FIGS. 1 and 2, reference numeral 1 denotes a cylindrical heating element, and this heating element 1 is constructed by sandwiching a heating resistor 4 between a ceramic base A2 and a ceramic base B3. The ceramic substrate A2 requires a predetermined thickness tA in order to minimize distortion during molding and maintain the mechanical strength of the heating element 1, and the ceramic substrate B3 requires a predetermined thickness tA to suppress distortion during molding as much as possible and maintain the mechanical strength of the heating element 1.
2, the thickness tB is much smaller than the thickness tA of the ceramic base 2. Further, the heating element 1 having a cylindrical shape has an inner pipe line 5, and a fluid inflow lower having a connecting screw 6 for connecting to a cold water supply pipe is provided at one end so as to communicate with the inner pipe line 6. . 8 is an outer case, and this outer case 8 houses a heating element 10.
A heating channel 9 is formed between the heating element 1 and the heating element 1.
The other end side of the inner pipe line 6 is closed, and a fluid outlet 10 is further provided located on the lower fluid inflow side. A spiral inner fin 11 is inserted into the heating channel e in order to give a swirling flow to the fluid to be heated and increase the flow velocity of the heating fluid in the heating channel 9. 121L is heating resistor 4
12b is a control unit, and 120 is a sensor.

また第１図におけるＬは加熱流路９の流路長さであり、
第２図におけるＤは加熱流路９の中心直径である。Moreover, L in FIG. 1 is the flow path length of the heating flow path 9,
D in FIG. 2 is the center diameter of the heating channel 9.

第３図ａ、ｂは上記一実施例における温水加熱装置の要
部断面斜視図と流れのベクトル図を示したもので、Ｖが
流速ベクトノペＮはインナーフィン１１の巻き数である
。FIGS. 3a and 3b show a cross-sectional perspective view of the main part of the hot water heating device in the above embodiment and a flow vector diagram, where V is the flow velocity and N is the number of turns of the inner fin 11.

第４図は、発熱素子１の表面温度を展開グラフとして示
したもので、この第４図中ＴＡは発熱素子１における内
管路６側の表面温度、ＴＢは加熱流路９側の表面温度を
示す。FIG. 4 shows the surface temperature of the heating element 1 as an expanded graph. In FIG. shows.

都電源に接続して発熱抵抗体４に通電し、流量が温水加
熱装置の使用最低水量または設定水量値である冷水を流
体流入ロアより第１図の矢印で示すように供給する。こ
の場合、前記最低水量または設定水量は、温水加熱装置
の使用水量範囲において最もスケール付着が厳しい条件
である。従って、前記最低水量または設定水量値におい
て、スケール付着温度以下に制御まだは保持することに
よって、スケール付着は解消できる。流入した冷水は内
管路５で加熱されながら左端開放部に達し、その後、発
熱素子１の外周に位置する加熱流路９に流入し、そして
インナーフィン１１により形成された螺旋状の加熱流路
９内を旋回しながら加熱され、流体流出口１０より温水
となって流出する。It is connected to the city power supply, the heat generating resistor 4 is energized, and cold water having a flow rate equal to the minimum water amount used by the hot water heating device or the set water amount value is supplied from the fluid inflow lower as shown by the arrow in FIG. In this case, the minimum amount of water or the set amount of water is the condition under which scale adhesion is most severe in the range of amount of water used by the hot water heating device. Therefore, scale adhesion can be eliminated by controlling or maintaining the water amount below the scale adhesion temperature at the minimum water amount or set water amount value. The inflowing cold water reaches the open left end portion while being heated in the inner pipe 5, then flows into the heating channel 9 located on the outer periphery of the heating element 1, and then flows into the spiral heating channel formed by the inner fin 11. It is heated while swirling in the fluid outlet 9 and flows out from the fluid outlet 10 as hot water.

この加熱工程において、水への熱伝達率、各基体ム２．
Ｂ３の厚みｔＡ、　ｔＢおよび熱伝導率との関係を用い
ると、発熱素子１の表面温度算出式は次のようになる。In this heating step, the heat transfer coefficient to water, each base layer 2.
Using the relationship between the thicknesses tA and tB of B3 and the thermal conductivity, the formula for calculating the surface temperature of the heating element 1 is as follows.

式は、各基体Ａ２　、Ｂ３から水への熱伝達率を各々α
Ａ、αＢ、セラミック基体Ａ２．Ｂ３の熱伝導率をλ、
各基体＆２　、Ｂ３の厚みをｔＡ、ｔＢ、水と接する発
熱素子１の表面積をＳＡ、ＳＢとし、また発熱素子１０
発熱抵抗体４の温度をＴＨ１発熱素子１の各基体ム２．
Ｂ３の表面温度を各々ＴＡ　、　ＴＢ、内管路６内の水
温をＴＷＡ、加熱流路ｅ内の水温をＴＷＢとすると、発
熱抵抗体４から各基体Ａ２，８３表面への伝熱量ＱＡ１
．　ＱＢＯは、ＱＡ−λ・（ＴＨ−ＴＡ　）・ＳＡ・−
ｔＡ ＱＢ−λ・（Ｔ）（−ＴＢ）・８Ｂ・１Ｂ となる。また、発熱素子１の基体Ａ２．Ｂ３の表面から
水への熱伝達量を各々１％Ａ　＋　１１．Ｂとすると、
争Ａ：αＡ・（ＴＡ−ＴＷＡ　）　＠ａｘす、二α８・
（ＴＢ　　Ｔｗｎ）・Ｓｇとなる。まだ熱バランスの関
係からＱ〔１Ａ＋ＱＢ＝鉤となる。よって ＱＢ　　ｔＢ、Ｊ−（ＴＨ−ＴＢ）・ｓＢ’　ｔＢｌ　
。The formula calculates the heat transfer coefficient from each substrate A2 and B3 to water by α
A, αB, ceramic substrate A2. The thermal conductivity of B3 is λ,
The thickness of each base &2, B3 is tA, tB, the surface area of the heating element 1 in contact with water is SA, SB, and the heating element 10 is
The temperature of the heating resistor 4 is determined by adjusting the temperature of each base member 2 of the heating element 1.
When the surface temperatures of B3 are TA and TB, the water temperature in the inner pipe 6 is TWA, and the water temperature in the heating channel e is TWB, the amount of heat transferred from the heating resistor 4 to the surface of each base A2, 83 is QA1.
．． QBO is QA-λ・(TH-TA)・SA・-
tA QB-λ・(T)(-TB)・8B・1B. Further, the base body A2 of the heating element 1. The amount of heat transferred from the surface of B3 to water is 1%A + 11. If it is B,
Conflict A: αA・(TA-TWA) @axsu, 2 α8・
(TB Twn)・Sg. Due to the heat balance, Q [1A + QB = hook. Therefore, QB tB, J-(TH-TB)・sB' tBl
.

α８・（ＴＢ−ＴＷＢ）・ＳＢ となる。従って、これから ＴＨ−ＴＢ　　　αＢ°ｔＢ”（ＴＢ−ＴＷＢ）１にす
るとＴＡ＝ＴＢとなり、発熱素子１の表面温度は等しく
力る。α8・(TB−TWB)・SB becomes. Therefore, if TH-TB αB°tB'' (TB-TWB) is set to 1 from now on, TA=TB, and the surface temperature of the heating element 1 becomes equal.

上記一実施例で示すように、外ケース８の内径が発熱素
子１の外径に比べて大きい場合、加熱流路９内にインナ
ーフィン１１を挿入しないと、加熱流路９における流速
は発熱素子１における内管路５の流速より小さいため、
基体Ａ２　、Ｂ３の表面から水への熱伝達率はαえ〉α
８となり、また基体Ａ２　、Ｂ３の厚みｔＡ、ｔＢはｔ
Ａ＞ｔＢであるだめ、Ｒは１を越え非常に大きな値とな
る。そしてまた第４図の点線で示すように、基体Ｂ３の
表面温度ＴＢ１′は、基体Ａ２の表面温度ＴＡ　、ｒに
比べて高くなる。As shown in the above embodiment, when the inner diameter of the outer case 8 is larger than the outer diameter of the heating element 1, if the inner fin 11 is not inserted into the heating passage 9, the flow velocity in the heating passage 9 will be lower than that of the heating element 1. Since it is smaller than the flow velocity of the inner pipe 5 in 1,
The heat transfer coefficient from the surfaces of substrates A2 and B3 to water is α〉α
8, and the thicknesses tA and tB of the bases A2 and B3 are t
Unless A>tB, R exceeds 1 and becomes a very large value. Also, as shown by the dotted line in FIG. 4, the surface temperature TB1' of the base body B3 is higher than the surface temperature TA, r of the base body A2.

次に、加熱流路９内にインナーフィン１１を挿入すると
、流体の流れは旋回流となる。この時の旋回流路長さＬ
ｏは第３図より、 となり、旋回流の流路長さＬｏは平行流の流路長さＬの
ＩＡｉｎθ倍長くなり、かつ流速も１／１ｓｉｎθ倍と
なる。従って、θの値を選定することにより、α□〈α
８を満たすようにαＢを増大させることがすなわち、第
４図の実線で示すようにＴＡ　ｊ　＋　ＴＢ　１をほぼ
等しい値に近づけることができる。また制御部１２ｂで
入力を制御することにより、発熱素子１０表面温度をス
ケール付着温度以下に保つことができる。Next, when the inner fin 11 is inserted into the heating channel 9, the fluid flow becomes a swirling flow. The swirl flow path length L at this time
According to FIG. 3, o is as follows, the flow path length Lo of the swirling flow is IAinθ times longer than the flow path length L of the parallel flow, and the flow velocity is also 1/1 sinθ times. Therefore, by selecting the value of θ, α□〈α
In other words, by increasing αB so as to satisfy 8, it is possible to bring TA j + TB 1 close to approximately equal values, as shown by the solid line in FIG. Furthermore, by controlling the input with the control section 12b, the surface temperature of the heating element 10 can be kept below the scale adhesion temperature.

上記説明からも明らかなように、流速の遅い加熱流路９
内にインナーフィン１１を挿入して加熱流路９内に旋回
流を発生させることにより、加熱流路９内の流速は速く
なり、その結果、熱伝達率が大きくなって、発熱素子１
の表面平均温度ははインナーフィン１１を挿入すること
により、加熱流路９に発生する旋回流に比べ、発熱素子
１の外周全面を均一な流速で流れる。そのだめ、発熱素
子１の表面上で局部的に高温となる部分はなくなり、そ
の結果、局部沸騰や、異常高温による発熱素子１の破壊
等を防ぐことができる。As is clear from the above description, the heating channel 9 with a slow flow rate
By inserting the inner fins 11 into the heating channel 9 and generating a swirling flow in the heating channel 9, the flow velocity in the heating channel 9 increases, and as a result, the heat transfer coefficient increases, and the heating element 1
By inserting the inner fins 11, the average surface temperature of the heat generating element 1 flows at a uniform velocity over the entire outer periphery of the heating element 1, compared to the swirling flow generated in the heating channel 9. As a result, there will be no locally heated portions on the surface of the heating element 1, and as a result, local boiling and destruction of the heating element 1 due to abnormally high temperatures can be prevented.

次に本発明の他の実施例について、第６図〜第６図にも
とづいて説明する。この実施例は、発熱素子の電気入力
を大きくするために、基体の径を太きくし、かつ外ケー
スの内径を小さくして、加熱流路幅を比較的狭くした場
合の実施例を示したものである。この第６図、第６図に
おいて、１３は円筒状に構成された発熱素子で、この発
熱素子１３はセラミック基体Ａ１４とセラミック基体Ｂ
１５とで発熱抵抗体１６を挾持することにより構成して
いる。そして前記基体ム１４は、成形時の歪みを極力押
さえ、かつ発熱素子１３の機械的強度を保持するため所
定の厚みｔＡを必要とし、また基体Ｂ１６は基体Ａ１４
の外周にローリングす　３ るため、基体Ａ１４の厚みｔＡに比べ非常に小さな厚み
ｔＢで構成されている。また円筒状に構成された発熱素
子１３は内管路１７を有するとともに、一端には、冷供
給管への接続ねじ１８を取付けた流体流入口１９を内管
路１７と連通するように設けている。２０は外ケースで
、この外ケース２０は発熱素子１３の外周との間に加熱
流路２１を形成し、かつ前記発熱素子１３の内管路１７
の他端側を閉塞し、さらに前記流体流入口１９側に位置
して流体流出口２２を設けている。また前記発熱素子１
３の内管路１７内には被加熱流体の流速を高めるため、
中子２３を挿入している。そしてこの中子２３は左端で
前記外ケース２ｏに袋ナツト２４により固定され、かつ
右方において、支持材２６により、発熱素子１３の中央
部に位置するように支持されている。２６１Ｌは発熱抵
抗体１６への通電用リード線、２６ｂは制御部、２６０
はセンサーである。Next, another embodiment of the present invention will be described based on FIGS. This example shows an example in which the diameter of the base body is increased, the inner diameter of the outer case is decreased, and the width of the heating channel is made relatively narrow, in order to increase the electrical input to the heating element. It is. 6, 13 is a cylindrical heating element, and this heating element 13 is composed of a ceramic substrate A 14 and a ceramic substrate B.
15 and a heat generating resistor 16 sandwiched therebetween. The base member 14 requires a predetermined thickness tA in order to suppress distortion during molding as much as possible and maintain the mechanical strength of the heating element 13, and the base member B16 requires a predetermined thickness tA to suppress distortion during molding as much as possible and maintain the mechanical strength of the heat generating element 13.
The base body A14 has a thickness tB that is much smaller than the thickness tA of the base body A14. The heating element 13 having a cylindrical shape has an inner pipe line 17, and a fluid inlet port 19 with a connecting screw 18 to the cold supply pipe is provided at one end so as to communicate with the inner pipe line 17. There is. Reference numeral 20 denotes an outer case, and this outer case 20 forms a heating passage 21 between it and the outer periphery of the heating element 13, and the inner pipe 17 of the heating element 13.
The other end is closed, and a fluid outlet 22 is further provided on the fluid inlet 19 side. Further, the heating element 1
In order to increase the flow velocity of the fluid to be heated,
Core 23 is inserted. The core 23 is fixed to the outer case 2o at the left end with a cap nut 24, and is supported at the right by a support member 26 so as to be located at the center of the heating element 13. 261L is a lead wire for energizing the heating resistor 16, 26b is a control unit, 260
is a sensor.

第７図ａ、ｂは各流水路の断面積を示したもので、Ｓｌ
は発熱素子１３の内管路１７の断面積、　４ Ｓ２は加熱流路２１の断面積、Ｓ３は中子２３の断面積
、Ｓ４は内管路１７の断面積Ｓ１より中子２３の断面積
Ｓ３を差し引いた断面積である。Figures 7a and b show the cross-sectional area of each flow channel.
is the cross-sectional area of the inner pipe 17 of the heating element 13, 4 S2 is the cross-sectional area of the heating channel 21, S3 is the cross-sectional area of the core 23, and S4 is the cross-sectional area of the core 23 from the cross-sectional area S1 of the inner pipe 17. This is the cross-sectional area after subtracting S3.

第８図は発熱素子１３０表面温度を示しだもので、実線
ＴＡ２は内管路１７側の表面温度、実線ＴＢ２は加熱流
路２１側の表面温度を示す。また点線ＴＡ２１　、　Ｔ
Ｂ２１　は中子２３を挿入する前の内管路１７側および
加熱流路２１側の各表面温度を示す。FIG. 8 shows the surface temperature of the heating element 130, where the solid line TA2 shows the surface temperature on the inner pipe line 17 side, and the solid line TB2 shows the surface temperature on the heating channel 21 side. Also dotted lines TA21, T
B21 indicates each surface temperature on the inner pipe path 17 side and the heating flow path 21 side before inserting the core 23.

上記構成において、通電用リード線２６を外部電源に接
続して発熱抵抗体１６に通電し、冷水を流体流入口１９
より第５図の矢印で示すように萩給する。そして流入し
た冷水は内管路１７で加熱されながら左端開放部に達し
、その後、発熱素子１３の外周に位置する加熱流路２１
に流入し、ここでさらに加熱され、流体流出口２２より
温水となって流出する。この加熱工程において、中子２
３が挿入されていない場合の発熱素子１３の表面温度算
出式は前述した一実施例の説明時に求めた次式になる。In the above configuration, the energizing lead wire 26 is connected to an external power source to energize the heating resistor 16, and the cold water is supplied to the fluid inlet 19.
Then feed the bushes as shown by the arrow in Figure 5. The inflowing cold water is heated in the inner pipe 17 and reaches the open left end, and then flows through the heating channel 21 located on the outer periphery of the heating element 13.
The water flows into the water, is further heated here, and flows out from the fluid outlet 22 as hot water. In this heating process, the core 2
The formula for calculating the surface temperature of the heating element 13 in the case where the heat generating element 13 is not inserted is the following formula, which was obtained when the above-mentioned embodiment was explained.

１５ ＴＨ−ＴＢ　　　αＢ・ｔＢ”（ＴＢ　　”ＷＢ）上記
第６図〜第６図で示す他の実施例のように、発熱素子１
３の内径が大きく、かつ加熱流路２１０幅が狭い場合は
、内管路１７内に中子２３を挿入しないと、内管路１７
内の流速は加熱流路２１の流速に比べて小さくなる。そ
のため、基体Ａ１４、Ｂ１５の表面から水への熱伝達率
はαよ（に対し非常に小さな値となる。その結果、第８
図に示すように、基体Ａ１４の表面温度ＴＡ２′は基体
Ｂ１６の表面温度ＴＢ（に比べて高くなる。15 TH-TB αB・tB” (TB “WB) As in the other embodiments shown in FIGS. 6 to 6 above, the heating element 1
3 has a large inner diameter and the width of the heating channel 210 is narrow, if the core 23 is not inserted into the inner pipe 17, the inner pipe 17
The flow velocity in the heating channel 21 is smaller than that in the heating channel 21. Therefore, the heat transfer coefficient from the surfaces of the substrates A14 and B15 to water becomes a very small value with respect to α.
As shown in the figure, the surface temperature TA2' of the substrate A14 is higher than the surface temperature TB of the substrate B16.

次に内管路１７内に中子２３を挿入すると、内管路１７
の断面積Ｓ４は５４−８ｌ−８３となって断面積が減少
する。したがって内管路１７内の流速は断面積の減少の
割合Ｓ４／Ｓ、　　に逆比例して増加するため、中子２
３の径を選定することにより、ＴＨ−ＴＢ２ の値が１に近づき、第８図の実線で示すように、ＴＡ２
　＋　’ｒＢ、、をほぼ等しい値に近づけることができ
る。寸だ制御部２６ｂで入力を制御することにより、発
熱素子１３の表面温度をスケール付着温度以下に保つこ
とができる。Next, when inserting the core 23 into the inner pipe line 17, the inner pipe line 17
The cross-sectional area S4 becomes 54-8l-83, and the cross-sectional area decreases. Therefore, the flow velocity in the inner pipe 17 increases in inverse proportion to the rate of decrease in cross-sectional area S4/S,
By selecting a diameter of 3, the value of TH-TB2 approaches 1, and as shown by the solid line in Fig. 8, TA2
+ 'rB, , can be brought close to approximately equal values. By controlling the input with the scale control section 26b, the surface temperature of the heating element 13 can be kept below the scale adhesion temperature.

上記説明からも明らかなように、流速の遅い発熱素子１
３の内管路１７内に中子２３を挿入して内管路１７内の
流速を速め、内管路１７側の熱伝達率を高めることによ
って、発熱素子１３０表面表面温度はほぼ等しい値とな
る。また中子２３により流れのコア部が破壊されて乱れ
が増加し、熱伝達率が増大する。さらに、中子２３が発
熱素子１３の支持部材となるだめ、発熱素子１３を外ケ
ース２ｏの中心位置に支持できる等の特徴を有する。As is clear from the above description, the heating element 1 with a slow flow rate
By inserting the core 23 into the inner pipe line 17 of No. 3 to increase the flow velocity in the inner pipe line 17 and increase the heat transfer coefficient on the inner pipe line 17 side, the surface temperature of the heating element 130 can be made to be approximately the same value. Become. Further, the core portion of the flow is destroyed by the core 23, turbulence increases, and the heat transfer coefficient increases. Furthermore, since the core 23 serves as a support member for the heating element 13, it has features such as being able to support the heating element 13 at the center of the outer case 2o.

なお、上記実施例においては、円筒状に構成された発熱
素子を用いたものについて説明したが、Ｎの発熱素子で
、その両側面に流通路を形成し　７ たものでも上記実施例と同様の効果が得られることは言
うまでもない。In the above embodiment, a heating element having a cylindrical shape was used. However, an N heating element with flow passages formed on both sides can also be used in the same manner as in the above embodiment. Needless to say, it is effective.

以上のように本発明の温水加熱装置は、流体の流速を変
え、流体への熱伝達率を変えることによって、発熱素子
の発熱抵抗体からセラミック基体−＼の熱伝達量を発熱
素子の両側面の表面平均温度が略等しくなるようにして
いるため、前記発熱素子の表面平均温度をスケール生成
温度以下に制御または保持することが容易となり、また
発熱素子の表面平均温度がほぼ等しいことから、発熱素
子の全表面を最適々熱交換条件に保つことができ、その
結果、発熱素子表面の熱交換効率を高めることができる
等のすぐれた効果を奏するものである。As described above, the hot water heating device of the present invention changes the amount of heat transferred from the heating resistor of the heating element to the ceramic substrate ＼ on both sides of the heating element by changing the flow rate of the fluid and changing the heat transfer coefficient to the fluid. Since the average surface temperatures of the heating elements are made to be approximately equal, it is easy to control or maintain the average surface temperature of the heating element below the scale generation temperature. The entire surface of the element can be maintained under optimal heat exchange conditions, and as a result, excellent effects such as the ability to increase the heat exchange efficiency on the surface of the heating element can be achieved.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明の一実施例を示す温水加熱装置の一部破
断側面図、第２図は第１図のＡ−Ａ′線断面図、第３図
ａ、ｂは第１図の要部拡大断面斜視図および流れのベク
トル図、第４図は同温水加熱装置における発熱素子の表
面温度の展開グラフ、第６図は本発明の他の実施例を示
す温水加熱装置　８ の一部破断側面図、第６図は第６図のＢ−Ｂ’巌断面図
、第７図ａ、ｂは第５図の各流路の流路断面積を示す断
面図、第８図は第６図の実施例における発熱素子の表面
温度の展開グラフ、第９図は従来の温水力１熱装置の一
部破断側面図、第１ｏ図は第９図のｃ−ｃ’線断面図、
第１１図は従来の円筒状面発熱体の表面温度を示す展開
グラフ、第１２図は重炭酸カルシウムのＰＨと温度と溶
解度との関係を示すグラフである。 １．１３・・・・・発熱素子、２，１４・・・・・・基
体人、３．１５・・・重体Ｂ、４，１６・・・・発熱抵
抗体、６．１７・・・・・内管路、９．２１・・印・加
熱流路、７゜１９・・・・・・流体流入口、８，２０・
・・・・外ケース、１０．２２・・・・・・流体流出口
。 代理人の氏名　弁理士　中　尾　敏　男　ほか１名第１
図 ／２７ 第２図 ０ 第３図 第４図 角　度０（°ン 第５図 第６図 ２？ 第７図 第８図 角屓θ／’Ｊ 第９図 第１０図 第１２図 水温（６Ｃ） ４９FIG. 1 is a partially cutaway side view of a hot water heating device showing an embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A' in FIG. 1, and FIGS. 3a and 3b are main points of FIG. 4 is a developed graph of the surface temperature of the heating element in the hot water heating device, and FIG. 6 is a partially broken view of the hot water heating device 8 showing another embodiment of the present invention. A side view, FIG. 6 is a cross-sectional view taken along line B-B' in FIG. 6, FIG. 7 a and b are cross-sectional views showing the cross-sectional area of each channel in FIG. FIG. 9 is a partially cutaway side view of a conventional hydronic single-heat device; FIG. 1o is a cross-sectional view taken along line c-c' in FIG. 9;
FIG. 11 is a developed graph showing the surface temperature of a conventional cylindrical surface heating element, and FIG. 12 is a graph showing the relationship between pH, temperature, and solubility of calcium bicarbonate. 1.13... Heat generating element, 2,14... Base person, 3.15... Heavy body B, 4,16... Heat generating resistor, 6.17...・Inner pipe line, 9.21...mark ・Heating channel, 7°19...Fluid inlet, 8,20...
...Outer case, 10.22...Fluid outlet. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure/27 Figure 2 Figure 0 Figure 3 Figure 4 Angle 0 (°) Figure 5 Figure 6 Figure 2? Figure 7 Figure 8 Angle angle θ/'J Figure 9 Figure 10 Figure 12 Water temperature ( 6C) 49

Claims (3)

【特許請求の範囲】[Claims] （１）２つのセラミック基体で発熱抵抗体を挾持して構
成した発熱素子と、この発熱素子の両側面に設けられ、
一方は流体流入口と連通し、かつ他方は流体流出口と連
通ずる流通路とを備え、前記流体流入口より供給される
使用最低流量または設定流量において、発熱抵抗体から
２つのセラミック基体への熱伝達量を、前記発熱素子の
両側面表面平均温度が略等しくなるように構成する手段
を設けるとともに、前記発熱素子の表面平均温度はスケ
ール生成温度以下に制御または保持するようにした温水
加熱装置。(1) A heating element configured by sandwiching a heating resistor between two ceramic substrates, and a heating element provided on both sides of the heating element,
A flow path is provided, one of which communicates with the fluid inlet, and the other communicates with the fluid outlet, and the heating resistor is connected to the two ceramic substrates at the lowest operating flow rate or set flow rate supplied from the fluid inlet. A hot water heating device comprising a means for configuring the amount of heat transfer so that the average temperatures of the surfaces of both side surfaces of the heating element are approximately equal, and the average surface temperature of the heating element is controlled or maintained below a scale generation temperature. . （２）前記発熱抵抗体から２つのセラミック基体への熱
伝達量を、前記発熱素子の両側面平均温度が略等しくな
るように構成する手段として、前記流体流出口と連通ず
る流通路に、加熱流体の流速を高める螺旋状のインナー
フィンを設けた特許請求の範囲第１項記載の温水加熱装
置。(2) As a means for configuring the amount of heat transferred from the heating resistor to the two ceramic substrates so that the average temperature on both sides of the heating element is approximately equal, heating is applied to the flow path communicating with the fluid outlet. The hot water heating device according to claim 1, further comprising a spiral inner fin that increases the flow velocity of the fluid. （３）前記発熱抵抗体から２つのセラミック基体への熱
伝達量を、前記発熱素子の両側面平均温度が略等しくな
るように構成する手段として、前記流体流入口と連通ず
る流通路の断面積を、流体流出口と連通ずる流通路の断
面積より大きくした際に、前記流体流入口と連通ずる流
通路に、加熱流体の流速を高める中子を挿入した特許請
求の範囲第１項記載の温水加熱装置。(3) A cross-sectional area of a flow path communicating with the fluid inlet as means for configuring the amount of heat transferred from the heating resistor to the two ceramic substrates so that the average temperature on both sides of the heating element is approximately equal. Claim 1, wherein a core is inserted into the flow passage communicating with the fluid inlet to increase the flow velocity of the heated fluid when the cross-sectional area of the flow passage communicating with the fluid outlet is made larger than the cross-sectional area of the flow passage communicating with the fluid outlet. Hot water heating device.