JPH035837Y2 - - Google Patents
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- Publication number
- JPH035837Y2 JPH035837Y2 JP12377785U JP12377785U JPH035837Y2 JP H035837 Y2 JPH035837 Y2 JP H035837Y2 JP 12377785 U JP12377785 U JP 12377785U JP 12377785 U JP12377785 U JP 12377785U JP H035837 Y2 JPH035837 Y2 JP H035837Y2
- Authority
- JP
- Japan
- Prior art keywords
- furnace
- heat
- heat medium
- heating
- hot air
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000010438 heat treatment Methods 0.000 claims description 37
- 239000007788 liquid Substances 0.000 claims description 5
- 238000011144 upstream manufacturing Methods 0.000 claims description 4
- 239000007789 gas Substances 0.000 description 5
- 239000000567 combustion gas Substances 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
Landscapes
- Drying Of Solid Materials (AREA)
Description
【考案の詳細な説明】
産業上の利用分野
本考案は、ワーク（工作物）の乾燥等に利用さ
れる間接加熱式熱風循環炉の改良に関するもので
ある。[Detailed Description of the Invention] Industrial Application Field The present invention relates to an improvement of an indirectly heated hot air circulation furnace used for drying workpieces, etc.
従来の技術
この種の炉は、従来第３図で示されるような構
成となつている。この図において、符号１，２，
３はワーク（図示せず）の通路に沿つて設置され
た作業炉であり、ワークはこの中を矢印方向へ進
行しつつ乾燥処理される。この乾燥には熱風が利
用され、該熱風を循環させるための熱風循環路
４，５，６が各作業炉１，２，３に設けられてい
る。符号７，８，９は熱風を循環させるためのフ
アンである。2. Description of the Related Art This type of furnace has conventionally been constructed as shown in FIG. In this figure, symbols 1, 2,
Reference numeral 3 denotes a working furnace installed along the path of the workpiece (not shown), and the workpiece is dried while traveling in the direction of the arrow. Hot air is used for this drying, and each work furnace 1, 2, 3 is provided with hot air circulation paths 4, 5, 6 for circulating the hot air. Reference numerals 7, 8, and 9 are fans for circulating hot air.
また、上記各熱風循環路４，５，６には各々熱
媒循環路１０，１１，１２が付設され、各熱媒循
環路１０，１１，１２には熱媒加熱部であるバー
ナ１３，１４，１５及び燃焼炉１６，１７，１８
が設けられている。また熱媒を循環させるための
フアン１９，２０，２１も設けられている。な
お、符号２２，２３，２４は燃料流量調節バルブ
であり、符号２５，２６，２７は排気ダクトであ
る。 Further, each of the hot air circulation paths 4, 5, and 6 is provided with a heat medium circulation path 10, 11, and 12, respectively, and each of the heat medium circulation paths 10, 11, and 12 is provided with burners 13, 14, which are heat medium heating sections. , 15 and combustion furnaces 16, 17, 18
is provided. Fans 19, 20, and 21 are also provided for circulating the heat medium. Note that numerals 22, 23, and 24 are fuel flow rate control valves, and numerals 25, 26, and 27 are exhaust ducts.
上記各熱風循環路４，５，６と各熱媒循環路１
０，１１，１２との所定の接点箇所には熱媒であ
る燃焼ガスから風に対して熱を与えるための熱交
換器２８，２９，３０が設けられている。 Each of the above hot air circulation paths 4, 5, 6 and each heat medium circulation path 1
Heat exchangers 28, 29, and 30 are provided at predetermined points of contact with the wind turbines 0, 11, and 12 for supplying heat from combustion gas, which is a heat medium, to the wind.
しかして、燃焼炉１６，１７，１８内でバーナ
１３，１４，１５からの燃料が燃焼されると、そ
の熱焼ガスがフアン１９，２０，２１の作用で各
熱媒循環路１０，１１，１２中を矢印方向に循環
し、また同時に熱風循環路４，５，６内において
も風がフアン７，８，９によつて矢印方向に流
れ、その間熱交換器２８，２９，３０によつて熱
媒から熱を受けて熱風ととなり、各作業炉１，
２，３内を経由する。作業炉１，２，３内にて該
熱風はワークに当り乾燥等の作業を行なうもので
ある。 When the fuel from the burners 13, 14, 15 is combusted in the combustion furnaces 16, 17, 18, the combustion gas is transferred to each heating medium circulation path 10, 11, 12 in the direction of the arrow, and at the same time in the hot air circulation paths 4, 5, 6, the air flows in the direction of the arrow by the fans 7, 8, 9, while the air is circulated in the direction of the arrow by the heat exchangers 28, 29, 30. It receives heat from the heating medium and becomes hot air, which is then sent to each work furnace 1,
Pass through 2 and 3. The hot air hits the workpieces in the work furnaces 1, 2, and 3 and performs operations such as drying.
考案が解決しようとする問題点
しかしながら、上記従来の炉は熱媒として燃焼
ガス等の気体を使用しているため、熱交換器２
８，２９，３０、配管等が大型化し、またフアン
１９，２０，２１等の動力も多く必要とするとい
う欠点を有している。Problems to be solved by the invention However, since the above-mentioned conventional furnace uses gas such as combustion gas as a heat medium, the heat exchanger 2
8, 29, 30, piping, etc. are large in size, and the fans 19, 20, 21, etc. require a large amount of power.
さらに、炉の稼動開始にあたり、その立ち上り
時間を短縮する必要があるが、そのためにはバー
ナ１３，１４，１５、燃焼炉１６，１７，１８等
の容量を稼動時負荷の倍以上に設定しなければな
らない。ところが、上記従来の方式であると各作
業炉１，２，３に対して上記バーナ１３，１４，
１５等を設けなければならないため、設備の大型
化が助長され、また稼動のための動力もさらに大
きなものが要求されるという欠点を有するもので
ある。 Furthermore, when the furnace starts operating, it is necessary to shorten the start-up time, but to do so, the capacity of burners 13, 14, 15, combustion furnaces 16, 17, 18, etc. must be set to more than twice the operating load. Must be. However, in the conventional method, the burners 13, 14,
15 etc. must be provided, which tends to increase the size of the equipment, and has the drawback that it requires even greater power for operation.
問題点を解決するための手段
本考案は上記問題点を解決するため、所定箇所
に熱媒加熱部を有する熱媒循環路と、所定箇所に
各作業炉を有する複数の熱風循環路とを備え、両
循環路の所定の接点箇所に上記風が上記熱媒から
熱を受け取るための熱交換器が設けられた間接加
熱式熱風循環炉において、上記熱媒循環路の熱媒
加熱部は１箇所のみ設けられると共に該熱媒は液
体とされ、かつ熱媒循環路は熱媒加熱部と上記各
熱交換器との間に形成されており、各熱媒循環路
の往路には制御弁が設置されると共に上記作業炉
の起動に際してワークの流れの上流側に位置する
作業炉に対応した制御弁から順次下流側の制御弁
に向けて経時的に開動作させる制御部が設けられ
ている構成を採用している。Means for Solving the Problems In order to solve the above problems, the present invention includes a heat medium circulation path having a heat medium heating section at a predetermined location, and a plurality of hot air circulation paths each having a working furnace at a predetermined location. In the indirect heating type hot air circulation furnace, in which a heat exchanger for the wind to receive heat from the heating medium is provided at a predetermined contact point of both circulation paths, the heating medium heating section of the heating medium circulation path is provided at one location. The heating medium is a liquid, and the heating medium circulation path is formed between the heating medium heating section and each of the heat exchangers, and a control valve is installed on the outgoing path of each heating medium circulation path. and a control section that opens the control valve sequentially from the control valve corresponding to the work furnace located on the upstream side of the flow of the work toward the downstream control valve when starting the work furnace. We are hiring.
作 用
熱媒循環路の熱媒としてガスでなく液体が用い
られている。また、その加熱部は１箇所である。
このため熱媒循環路及びその周辺は小型化され、
占有スペースも小さくなつている。Function: A liquid rather than a gas is used as the heating medium in the heating medium circuit. Moreover, there is only one heating section.
For this reason, the heat medium circulation path and its surroundings have been downsized,
The space it occupies is also getting smaller.
炉の稼動に際して制御部が作動すると、ワーク
の流れの上流側に位置する作業炉の制御弁が開い
て第１作業炉内の予熱がなされる。この予熱は通
常運転時の熱量の倍程度を使用することによりな
されるから迅速に立ち上る。制御部のタイマ等で
設定される所定時間が経過し、第１作業炉内が所
定温度に到達すると、次の第２作業炉に対応する
制御弁がさらに開かれて第２作業炉内に熱風が流
入する。このとき第１作業炉はすでに立ち上つて
いてその負荷は小さいので、熱量は第２作業炉の
方へより多く供給されることになる。さらに所定
時間が経過すると、第３作業炉に対応する制御弁
が開かれ、上記と同様の理由から、第１，第２よ
りも第３作業炉の方へより多く熱量が配分される
こととなる。 When the control unit is activated during operation of the furnace, a control valve of the work furnace located upstream of the flow of the workpiece is opened, and the inside of the first work furnace is preheated. This preheating is done by using about twice the amount of heat used during normal operation, so it starts up quickly. When a predetermined time set by a timer or the like in the control unit has passed and the temperature inside the first work furnace reaches a predetermined temperature, the control valve corresponding to the next second work furnace is further opened to blow hot air into the second work furnace. will flow in. At this time, the first working furnace has already started up and its load is small, so more heat is supplied to the second working furnace. Furthermore, after a predetermined period of time has elapsed, the control valve corresponding to the third working furnace is opened, and for the same reason as above, more heat is distributed to the third working furnace than to the first and second working furnaces. Become.
したがつて、全作業炉の立ち上がりが速やかに
なされることになる。 Therefore, all working furnaces will be started up quickly.
実施例
第１図及び第２図は本考案の一実施例を示して
いる。なお、これらの図において第３図における
と同一構成をとるものについては同一符号を付す
る。Embodiment FIGS. 1 and 2 show an embodiment of the present invention. Components in these figures that have the same configuration as in FIG. 3 are given the same reference numerals.
第１図で示されるように、熱媒加熱部３１は１
箇所のみ設けられている。また、熱媒も気体では
なくて液体である油が使用されている。熱媒加熱
部３１はボイラであり、該ボイラにはバーナ３
２、排気ダクト３３等が付設されている。なお、
符号３４は燃料調節弁であり、符号３５はバーナ
３２に新鮮な空気を送るための導管であり、符号
３６は該空気を排ガスで予熱するための熱交換器
である。 As shown in FIG. 1, the heat medium heating section 31 has one
Only certain locations are provided. Furthermore, the heat medium used is not gas but liquid oil. The heat medium heating section 31 is a boiler, and the boiler includes a burner 3.
2. An exhaust duct 33 etc. are attached. In addition,
Reference numeral 34 is a fuel control valve, reference numeral 35 is a conduit for sending fresh air to the burner 32, and reference numeral 36 is a heat exchanger for preheating the air with exhaust gas.
上記熱媒加熱部３１と各熱風循環路４，５，６
の熱交換器３７，３８，３９との間には熱媒循環
路４０，４１，４２が並列的に形成されており、
各往路には電磁弁などの制御弁４３，４４，４５
が設置されている。また所定箇所にはポンプ４６
が設置されている。これらの制御弁４３，４４，
４５はすべて制御部４７によつて制御されるよう
になつており、制御部４７はタイマ等を備え、作
業炉１，２，３の起動に際してワークの流れの上
流側に位置する作業炉１に対応した制御弁４３か
ら順次下流側の制御弁４４，４５に向けて経時的
に開動作させるよう構成されている。一つの制御
弁の開動作から次の弁の開動作に至るまでの時間
Ｔは一つの作業炉の立上り時間とほぼ一致してい
る。 The heat medium heating section 31 and each hot air circulation path 4, 5, 6
Heat medium circulation paths 40, 41, 42 are formed in parallel between the heat exchangers 37, 38, 39,
Control valves 43, 44, 45 such as solenoid valves are provided on each outward path.
is installed. In addition, a pump 46 is installed at a predetermined location.
is installed. These control valves 43, 44,
45 are all controlled by a control unit 47, and the control unit 47 is equipped with a timer, etc., and when starting up the work furnaces 1, 2, and 3, the control unit 47 controls the work furnace 1 located on the upstream side of the workpiece flow. It is configured to sequentially open the control valves 44 and 45 downstream from the corresponding control valve 43 over time. The time T from the opening operation of one control valve to the opening operation of the next valve almost coincides with the start-up time of one working furnace.
しかして、作業炉１，２，３の始動に際して
は、熱媒加熱器３１であるボイラが稼動され、熱
媒の加熱がなされる。この熱媒たる油は比熱が
424（Kal／m3，℃）であり、従来の熱媒たる空気
の0.30（Kcal／m3・℃）の約１，400倍にあたり、
それ故、熱媒循環路４０，４１，４２の配管、ポ
ンプ４６は従来のものに比べ格段に小型化されて
いる。また、熱交換器３７，３８，３９も従来の
気体−気体方式に対して気体−液体方式となり、
熱通過率（Kcal／m2・ｈ・℃）が約２倍になる
ため従来の大きさの半分程度のものを使用し得る
ものである。 Thus, when starting up the working furnaces 1, 2, and 3, the boiler, which is the heat medium heater 31, is operated to heat the heat medium. This heating medium, oil, has a specific heat of
424 (Kcal/m 3 ℃), which is approximately 1,400 times the 0.30 (Kcal/m 3 ℃) of air, which is a conventional heating medium.
Therefore, the piping of the heat medium circulation paths 40, 41, 42 and the pump 46 are much smaller than those of the conventional ones. In addition, the heat exchangers 37, 38, and 39 are also of a gas-liquid type instead of the conventional gas-gas type,
Since the heat transfer rate (Kcal/m 2 ·h ·°C) is approximately doubled, it is possible to use a device that is about half the size of the conventional one.
次いで、制御部４７からの信号に基づき、制御
弁４３が開かれ、熱媒が熱交換器３７に至り、一
方フアン７の作動による風が熱風循環路４中を循
環しつつ熱交換器３７で熱を受け取り作業炉１内
を加熱する。第２図Ａで示されるように、この制
御弁４３のみが開かれる時間Ｔはこの作業炉１の
立ち上り時間に相当し、このＴをできるだけ短縮
するためバーナ３２の容量はこの間標準稼動時に
該作業炉１の負荷をＱとすれば例えば2Qに設定
される。この作業炉１内の温度が所定の高さに立
ち上れば、制御部４７の図示しない検知器により
検知されさらに次の制御弁４４が開かれる。 Next, the control valve 43 is opened based on a signal from the control unit 47, and the heat medium reaches the heat exchanger 37, while the air generated by the operation of the fan 7 circulates in the hot air circulation path 4 and flows through the heat exchanger 37. It receives heat and heats the inside of the working furnace 1. As shown in FIG. 2A, the time T during which only the control valve 43 is opened corresponds to the start-up time of the working furnace 1, and in order to shorten this time T as much as possible, the capacity of the burner 32 is reduced during the normal operation. If the load of the furnace 1 is Q, it is set to 2Q, for example. When the temperature inside the working furnace 1 rises to a predetermined level, it is detected by a detector (not shown) in the control section 47, and the next control valve 44 is opened.
この結果、第２図Ｂで示されるように下流側の
隣接作業炉２に2Qの熱量が加えられるようバー
ナ３２の容量が2Q＋Ｑ＝3Qとして調節され、該
炉２も時間Ｔの間はより多く加熱されて立ち上り
時間の短縮化がなされる。時間Ｔが経過すると、
さらに次の制御弁４５が開かれる。 As a result, as shown in FIG. 2B, the capacity of the burner 32 is adjusted as 2Q+Q=3Q so that 2Q of heat is added to the adjacent work furnace 2 on the downstream side, and the furnace 2 also increases the amount of heat during time T. It is heated and the rise time is shortened. When time T has passed,
Furthermore, the next control valve 45 is opened.
その結果、第２図Ｃで示されるように、さらに
下流側の作業炉３に2Qの熱量が加えられるよう
にバーナ３２の容量が2Q＋Ｑ＋Ｑ＝4Qとして調
節され、該炉３も時間Ｔの間より多く加熱されて
立ち上り時間の短縮化がなされる。時間Ｔが経過
するとバーナ３２の容量は3Qに調整され、作業
炉３は負荷3Qの標準稼動状態とされて、ワーク
の炉１，２，３内への搬入が開始されることとな
る。 As a result, as shown in FIG. A large amount of heat is generated, and the rise time is shortened. When the time T has elapsed, the capacity of the burner 32 is adjusted to 3Q, the work furnace 3 is brought into a standard operating state with a load of 3Q, and workpieces are started to be carried into the furnaces 1, 2, and 3.
ここで、従来の方式と比較すると、従来は炉
１，２，３の始動に際し立ち上り時間を短縮する
ためバーナ１３，１４，１５の容量を2Qに設定
するとすれば、作業炉がＮ個あるとして、全体で
2QNを必要とする。これに対し、本考案によれ
ば、バーナ３２の容量はＱ（Ｎ＋１）で済ませ得
るものである。従つて、そのバーナ容量の低減割
合は作業炉の個数が多いほど大きくなるという好
結果をもたらすものである。 Here, in comparison with the conventional system, if the capacity of burners 13, 14, 15 is set to 2Q in order to shorten the start-up time when starting furnaces 1, 2, and 3, then assuming that there are N working furnaces, , in total
Requires 2QN. On the other hand, according to the present invention, the capacity of the burner 32 can be reduced to Q(N+1). Therefore, the reduction rate of the burner capacity increases as the number of working furnaces increases, which is a good result.
考案の効果
本考案は以上のような構成及び作用からなるの
で、熱媒加熱部３１、熱媒循環路４０，４１，４
２熱交換器３７，３８，３９等の小型化をなし
得、従つて、間接加熱式熱風循環炉全体の構成を
簡素にし、占有スペースの減少、放熱損失等の設
備の固定損失の低減を図り得るものである。Effects of the invention Since the present invention has the above-described configuration and operation, the heating medium heating section 31, the heating medium circulation paths 40, 41, 4
2 The heat exchangers 37, 38, 39, etc. can be downsized, and the overall configuration of the indirect heating type hot air circulation furnace can be simplified, occupying space, and fixed losses of equipment such as heat radiation loss can be reduced. It's something you get.
さらに、作業炉の立ち上り時間を短くした状態
において熱媒加熱部３１のバーナ３２の低容量化
を図り得るので、作業炉１，２，３の標準稼動下
におけるバーナ３２の効率向上を図り得るもので
ある。しかもバーナ３２の容量は、従来方式が
2NQ必要であるとすれば、本考案ではＱ（Ｎ＋
１）で済むので、作業炉１，２，３を増設する場
合等において特に有益である。 Furthermore, since the capacity of the burner 32 of the heat medium heating section 31 can be reduced in a state where the start-up time of the work furnace is shortened, the efficiency of the burner 32 can be improved under standard operation of the work furnaces 1, 2, and 3. It is. Moreover, the capacity of the burner 32 is smaller than that of the conventional method.
If 2NQ is necessary, in this invention Q(N+
1) is sufficient, so it is particularly useful when increasing the number of working furnaces 1, 2, and 3.
第１図及び第２図は本考案の間接加熱式熱風循
環炉の一実施例を示し、第１図はそのブロツク回
路図、第２図はその操作の一例を示すブロツク回
路図で、Ａは炉の起動時、ＢはＴ時間後Ｃは2T
時間に夫々該当するものであり、第３図は従来方
式のブロツク回路図である。
１，２，３：作業炉、４，５，６：熱風循環
路、３１：熱媒加熱部、３２：バーナ、３７，３
８，３９：熱交換器、４０，４１，４２：熱媒循
環路、４３，４４，４５：制御弁、４６：ポン
プ、４７：制御部。
1 and 2 show an embodiment of the indirect heating type hot air circulation furnace of the present invention, FIG. 1 is a block circuit diagram thereof, and FIG. 2 is a block circuit diagram showing an example of its operation. When the furnace is started, B is T hours later, C is 2T.
FIG. 3 is a block circuit diagram of a conventional system. 1, 2, 3: Working furnace, 4, 5, 6: Hot air circulation path, 31: Heat medium heating section, 32: Burner, 37, 3
8, 39: heat exchanger, 40, 41, 42: heat medium circulation path, 43, 44, 45: control valve, 46: pump, 47: control section.
Claims (1)
所定箇所に各作業炉を有する複数の熱風循環路と
を備え、両循環路の所定の接点箇所に上記風が上
記熱媒から熱を受け取るための熱交換器が設けら
れた間接加熱式熱風循環炉において、上記熱媒循
環路の熱媒加熱部は１箇所のみ設けられると共に
該熱媒は液体とされ、かつ熱媒循環路は熱媒加熱
部と上記各熱交換器との間に形成されており、各
熱媒循環路の往路には制御弁が設置されると共に
上記作業炉の起動に際してワークの流れの上流側
に位置する作業炉に対応した制御弁から順次下流
側の制御弁に向けて経時的に開動作させる制御部
が設けられていることを特徴とする間接加熱式熱
風循環炉。 a heating medium circulation path having a heating medium heating section at a predetermined location;
An indirect heating hot air circulation system comprising a plurality of hot air circulation paths each having a working furnace at a predetermined location, and a heat exchanger for the air to receive heat from the heating medium at a predetermined contact point between the two circulation paths. In the furnace, the heat medium heating section of the heat medium circulation path is provided at only one location, the heat medium is in liquid form, and the heat medium circulation path is formed between the heat medium heating section and each of the heat exchangers. A control valve is installed on the outgoing path of each heat medium circulation path, and when starting the above-mentioned work furnace, the control valve corresponding to the work furnace located on the upstream side of the flow of workpieces is sequentially directed to the downstream control valve. An indirect heating type hot air circulation furnace characterized by being provided with a control unit that opens the furnace over time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12377785U JPH035837Y2 (en) | 1985-08-12 | 1985-08-12 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12377785U JPH035837Y2 (en) | 1985-08-12 | 1985-08-12 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6232994U JPS6232994U (en) | 1987-02-26 |
| JPH035837Y2 true JPH035837Y2 (en) | 1991-02-14 |
Family
ID=31015190
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12377785U Expired JPH035837Y2 (en) | 1985-08-12 | 1985-08-12 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH035837Y2 (en) |
-
1985
- 1985-08-12 JP JP12377785U patent/JPH035837Y2/ja not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6232994U (en) | 1987-02-26 |
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