JP2900609B2 - Absorption refrigerator - Google Patents

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

技術分野 本発明は、主に冷媒に水を、吸収溶液に臭化リチウム
水溶液をそれぞれ用い、構成機器として、蒸発器、吸収
器、高温発生器、低温発生器及び凝縮器を備える二重効
用形の吸収式冷凍機に関する。 背景技術 従来、特開昭63−251764号公報に開示され且つ図３に
示すように、冷媒液の散布器１及び冷水管Ｗをもつ蒸発
器Ａと、該蒸発器Ａと同一容器Ｕ内にエリミネータＭを
挟んで隣接状に設けられ、濃溶液の散布器Ｓ及び冷却水
配管Ｒをもつ吸収器Ｂと、該吸収器Ｂと溶液ポンプＧ並
びに低温熱交換器Ｌ及び高温熱交換器Ｈを介して接続さ
れ、バーナーＶを加熱源として吸収器Ｂで多量に冷媒を
含んだ稀溶液から冷媒を発生させる高温発生器Ｃと、こ
の高温発生器Ｃで発生する冷媒蒸気を流す加熱器Ｋをも
ち、高温発生器Ｃで再生されて高温熱交換器Ｈを通過し
た後の中間濃度溶液から冷媒を発生させる低温発生器Ｄ
と、該低温発生器Ｄと同一容器Ｔ内に設けられ、吸収器
Ｂの冷却水配管Ｒの後段に連続して設ける冷却水配管Ｊ
により各発生器C,Dで発生した冷媒蒸気を凝縮させる凝
縮器Ｅとを備えている。こうして、蒸発器Ａにおいて、
散布する冷媒の蒸発により、冷水管Ｗに冷房負荷に供給
する冷水を取り出すようにしている。 以上の構成で、バーナーＶによる加熱量は、燃料制御
弁Ｘの開度調節により可変としており、冷水管Ｗの出口
に設ける温度検出器Ｙで検出し、冷房負荷を示す冷水出
口温度の大小に応じて、制御装置Ｆからその開度を図４
に示すように増減制御するようにしており、この場合、
外気の温度が同じでも湿度が低いと実負荷が小さく、バ
ーナーＶによる加熱量を減らして省エネが図れることか
ら、湿度の値と相関関係にある外付の冷却塔（図示せ
ず）下流の冷却水入口温度を温度検出器Ｚで検出し、そ
の冷却水入口温度が低いと、冷水入口温度に対する開度
変化の勾配を緩やかにすると共に、開度上限値を小さく
するようにしている。 しかし、以上のものでは、冷却水入口温度が低いと、
一律に燃料制御弁Ｘの開度を小さく制限しているため、
運転の立上げ時等で、冷却水の入口温度は低いが100％
の定格燃焼によって早く定常運転に移行させたい場合
や、負荷の急増で、その負荷に迅速に対応させて能力を
出したい場合等にも、加熱量が冷却水入口温度に支配さ
れて制限されてしまうため、能力を十分に発揮すること
ができず、応答遅れが生じる問題がある。 又、以上のものでは、冷却水入口温度が低いと高温発
生器Ｃの加熱量が制限されるため、該高温発生器Ｃでの
圧力高をある程度は抑制できるが、溶液配管系内に空気
等が混入したり、多量に水素ガスが発生する等の異常事
態が生じた場合には、最早、冷却水入口温度による加熱
量の制限制御では全く対応できない問題もある。 発明の開示 本発明では、一応、冷却水入口温度によって高温発生
器の最高許容温度は設定するが、基本的には、冷水出口
温度等の冷房負荷の大小に応じてその加熱量を増減制御
し、高温発生器内の温度が冷却水入口温度によって定め
た最高許容温度を越えることとなる場合にのみ、本来の
冷房負荷に基づく加熱量を減らすこととし、運転の立上
げ時等に対応させて応答性のよい制御を確保しながら、
冷却水温が低い場合の過剰冷凍能力を抑制して省エネを
図ると共に、冷却水温に拘らず、多量の水素ガスが発生
した時等の異常事態発生時も、高温発生器内での圧力高
を回避できる吸収式冷凍機を提供することをその目的と
する。 そこで、上記の目的を達成するために、図１に示すよ
うに、冷媒を蒸発させて冷房負荷に供給する冷熱を取り
出す蒸発器１、該蒸発器１で蒸発した冷媒を溶液に吸収
させる吸収器２、該吸収器２で冷媒を吸収した溶液から
冷媒を発生させる高温発生器３及び低温発生器４、これ
ら発生器3,4で発生した冷媒を凝縮させる凝縮器５を備
え、冷房負荷の大小に応じて前記高温発生器３に具備す
る加熱源31の加熱量を増減制御する加熱量制御手段32を
設けた吸収式冷凍機において、前記吸収器２に配管する
冷却水配管23に流す冷却水の温度を検出する第一温度検
出手段７と、前記高温発生器３の温度を検出する第二温
度検出手段８と、前記第一温度検出手段７の検出値の大
小に応じて前記高温発生器３の最高許容温度の高低を定
める限界温度設定手段９と、前記第二温度検出手段８の
検出値が前記限界温度設定手段９で設定する最高許容温
度を越えることになるとき前記加熱量制御手段32に加熱
量の減少指令を与える加熱量抑制手段10とを設けた。 この場合、最もポピュラーな仕様において上記目的を
達成するために、つぎの工夫も講じた。即ち、加熱源31
がバーナー31aであり、加熱量制御手段32がバーナー31a
への燃料供給を開度調節により制御する燃料制御弁32a
であるものとした。又、冷房負荷の検出手段が、蒸発器
１に配管する冷水管11の出口に設ける冷水出口温度検出
手段14であるもの、あるいは、蒸発器１に配管する冷水
管11に流す冷水の出入口温度差を検出する冷水出入口温
度差検出手段であるものとした。更に、第一温度検出手
段７が、吸収器２に配管する冷却水配管23に流す冷却水
の入口温度Ttを検出する冷却水入口温度検出手段である
ものとした。 そして、第一温度検出手段７を冷却水入口温度検出手
段で構成したものにおいては、その冷却水入口温度との
関係で高温発生器３の最高許容温度を適切に定めるた
め、限界温度設定手段９は、第一温度検出手段７で検出
する冷却水入口温度Ttが、所定値よりも低い範囲では、
該冷却水入口温度Ttに比例した最高許容温度とし、所定
値以上の範囲では、一定の最高許容温度とするものとす
るのが好ましく、この場合には、異常な温度上昇による
圧力高を一層良好に防止できる。 更に、限界温度設定手段９は、第一温度検出手段７で
検出する冷却水入口温度Ttが、第１の所定値よりも低い
範囲では、該冷却水入口温度Ttに比例した最高許容温度
とし、前記第１の所定値以上で且つこれよりも高い第２
の所定値よりも低い範囲では、一定の最高許容温度と
し、第２の所定値以上の範囲では、冷却水入口温度Ttに
反比例した最高許容温度とするものとするのも好まし
く、この楊合には、異常な温度上昇による圧力高をより
一層確実に防止できる。 又、更に、加熱量を本来の冷房負荷に応じた値から出
来るだけ逸脱させないで制御を行うため、加熱量抑制手
段10は、所定時間毎に加熱量を一ステップずつ段階的に
制限していくステップ制限手段であるものとした。 以上のように構成する吸収式冷凍機の作用効果を以下
説明する。第一温度検出手段７で検出する冷却水温が低
い場合には、冷却水温が高い場合に比べ、限界温度設定
手段９により、高温発生器３の最高許容温度が低く設定
される。この冷却水温の低い条件下での定常運転時に
は、冷却水温が高い場合に比べて、同じ温度の冷房負荷
であっても高温発生器３での加熱量を抑制できることか
ら、第二温度検出手段８で検出する高温発生器３の温度
が、低く定められた最高許容温度を越えることとなる限
りにおいて、加熱量抑制手段10によりその加熱量が減ら
されるため、過剰冷凍能力を抑制できて、省エネが図れ
る。しかも、冷却水温が低い場合にも、運転の立上げ時
等、高温発生器３の温度が最高許容温度をなかなか越え
ない場合には、大きな冷房負荷に対応して高温発生器３
での加熱量を十分に確保できるため、応答性を高めるこ
ともできる。 又、冷却水温が高い場合にも、高温発生器３の温度が
最高許容温度を越えることとなる限りにおいて、加熱量
抑制手段10によりその加熱量が減らされるため、高温発
生器３での圧力高を回避できる。その上、冷却水温の高
低に拘らず、高温発生器３の温度が最高許容温度を越え
ることとなる限りにおいて、加熱量抑制手段10によりそ
の加熱量が減らされるため、多量の水素ガス発生時等の
異常事態発生時にも、高温発生器３での圧力高を回避で
きる。 特に本発明では、低温発生器４の温度ではなく、高温
発生器３の温度に基づいて加熱量の抑制制御を行ってい
るから、次の利点も有する。すなわち、運転の立ち上げ
時から、高温発生器３の方が低温発生器４よりも温度が
高く低温発生器４の温度で限界値を決めたとすると、高
温発生器３の温度が異常に上がったときに問題が生じ
る。つまり、燃焼ガスの圧力が設計値より高くなってい
る場合や、腐食により発生する不凝縮ガス（例えば水
素）が機内に溜っている場合等の原因で、本来的に大気
圧以下で運転することを前提にしている高温発生器３の
温度が異常に上がり、圧力が大気圧より高くなる恐れが
ある。 また、温度が高い程臭化リチウム水溶液を用いた吸収
液の腐食性が増すので、機器の腐食を異常に進行させる
怖れがある。 しかしながら、本発明では、高温発生器３の温度に基
づいて加熱量を抑制しているから、これらの問題を回避
し、適切な制御が行えるのである。 図面の簡単な説明TECHNICAL FIELD The present invention mainly uses water as a refrigerant and an aqueous solution of lithium bromide as an absorbing solution, and has a double-effect type including an evaporator, an absorber, a high-temperature generator, a low-temperature generator, and a condenser as constituent devices. The present invention relates to an absorption refrigerator. 2. Description of the Related Art Conventionally, as shown in FIG. 3 and disclosed in Japanese Patent Application Laid-Open No. 63-251764, an evaporator A having a refrigerant liquid sprayer 1 and a cold water pipe W, and an evaporator A in the same container U An absorber B provided adjacent to the eliminator M and having a concentrated solution sprayer S and a cooling water pipe R; the absorber B, a solution pump G, a low-temperature heat exchanger L and a high-temperature heat exchanger H; A high temperature generator C, which is connected via a burner V and generates a refrigerant from a dilute solution containing a large amount of refrigerant in an absorber B using a burner V as a heating source, and a heater K through which refrigerant vapor generated in the high temperature generator C flows. A low-temperature generator D that generates a refrigerant from the intermediate-concentration solution after being regenerated by the high-temperature generator C and passing through the high-temperature heat exchanger H
And a cooling water pipe J provided in the same vessel T as the low-temperature generator D and continuously provided after the cooling water pipe R of the absorber B.
And a condenser E for condensing the refrigerant vapor generated in each of the generators C and D. Thus, in the evaporator A,
The cooling water to be supplied to the cooling water pipe W is supplied to the cooling water pipe W by evaporation of the sprayed refrigerant. With the above configuration, the amount of heating by the burner V is variable by adjusting the opening of the fuel control valve X. The amount of heating is detected by a temperature detector Y provided at the outlet of the chilled water pipe W. In response, the controller F changes the opening degree from FIG.
The increase / decrease control is performed as shown in FIG.
Even if the temperature of the outside air is the same, if the humidity is low, the actual load is small, and the amount of heating by the burner V can be reduced to save energy. Therefore, cooling downstream of an external cooling tower (not shown) that is correlated with the humidity value. The water inlet temperature is detected by the temperature detector Z, and when the cooling water inlet temperature is low, the gradient of the opening change with respect to the cold water inlet temperature is made gentler and the opening upper limit value is made smaller. However, in the above, if the cooling water inlet temperature is low,
Since the opening of the fuel control valve X is uniformly limited to a small value,
At the start of operation, etc., the cooling water inlet temperature is low but 100%
Also, when it is desired to shift to steady operation as soon as possible due to the rated combustion, or when it is desired to quickly respond to the load due to a sudden increase in load and to increase the capacity, the heating amount is controlled by the cooling water inlet temperature and is limited. Therefore, there is a problem that the ability cannot be sufficiently exhibited and a response delay occurs. Further, in the above-described apparatus, when the cooling water inlet temperature is low, the heating amount of the high-temperature generator C is limited, so that the high pressure in the high-temperature generator C can be suppressed to some extent. When an abnormal situation occurs, such as when water is mixed in or when a large amount of hydrogen gas is generated, there is a problem that the limitation control of the heating amount by the cooling water inlet temperature can no longer cope at all. DISCLOSURE OF THE INVENTION In the present invention, for the time being, the maximum allowable temperature of the high-temperature generator is set according to the cooling water inlet temperature, but basically, the heating amount is increased or decreased according to the magnitude of the cooling load such as the chilled water outlet temperature. Only when the temperature in the high temperature generator exceeds the maximum allowable temperature determined by the cooling water inlet temperature, the heating amount based on the original cooling load is reduced, and While securing responsive control,
Suppresses excessive refrigeration capacity when the cooling water temperature is low, saves energy, and avoids high pressure inside the high-temperature generator even when an abnormal situation occurs, such as when a large amount of hydrogen gas is generated, regardless of the cooling water temperature. It is an object of the present invention to provide an absorption type refrigerator that can be used. Therefore, in order to achieve the above object, as shown in FIG. 1, an evaporator 1 for evaporating a refrigerant and extracting cold heat to be supplied to a cooling load, and an absorber for absorbing the refrigerant evaporated by the evaporator 1 into a solution. 2, a high-temperature generator 3 and a low-temperature generator 4 for generating a refrigerant from a solution in which the refrigerant has been absorbed by the absorber 2, and a condenser 5 for condensing the refrigerant generated by the generators 3, 4; In the absorption chiller provided with the heating amount control means 32 for increasing or decreasing the heating amount of the heating source 31 provided in the high temperature generator 3 in accordance with the condition, the cooling water flowing through the cooling water pipe 23 provided to the absorber 2 First temperature detecting means 7 for detecting the temperature of the high-temperature generator 3, second temperature detecting means 8 for detecting the temperature of the high-temperature generator 3, and the high-temperature generator according to the magnitude of the detection value of the first temperature detecting means 7. Limit temperature setting means 9 for determining the level of the maximum allowable temperature of 3 When the detected value of the second temperature detecting means 8 exceeds the maximum allowable temperature set by the limit temperature setting means 9, a heating amount suppressing means 10 for giving a heating amount decreasing command to the heating amount controlling means 32; Was provided. In this case, in order to achieve the above-mentioned object in the most popular specifications, the following measures were taken. That is, the heating source 31
Is the burner 31a, and the heating amount control means 32 is the burner 31a.
Control valve 32a that controls the fuel supply to the engine by adjusting the opening
It was assumed that. Further, the cooling load detecting means is the chilled water outlet temperature detecting means 14 provided at the outlet of the chilled water pipe 11 connected to the evaporator 1, or the difference between the inlet and outlet temperature of the chilled water flowing through the chilled water pipe 11 connected to the evaporator 1. Is a means for detecting the difference in temperature between the cold water inlet and the outlet. Further, the first temperature detecting means 7 is a cooling water inlet temperature detecting means for detecting an inlet temperature Tt of the cooling water flowing through the cooling water pipe 23 connected to the absorber 2. In the case where the first temperature detecting means 7 is constituted by the cooling water inlet temperature detecting means, the maximum allowable temperature of the high temperature generator 3 is appropriately determined in relation to the cooling water inlet temperature. In the range where the cooling water inlet temperature Tt detected by the first temperature detecting means 7 is lower than a predetermined value,
It is preferable that the maximum allowable temperature is in proportion to the cooling water inlet temperature Tt, and a predetermined maximum allowable temperature is set in a range equal to or higher than a predetermined value. In this case, the pressure rise due to an abnormal temperature rise is further improved. Can be prevented. Further, the limit temperature setting means 9 sets the maximum allowable temperature in proportion to the cooling water inlet temperature Tt when the cooling water inlet temperature Tt detected by the first temperature detecting means 7 is lower than a first predetermined value, A second not less than the first predetermined value and higher than the first predetermined value;
It is also preferable to set the maximum allowable temperature in a range lower than the predetermined value, and to set the maximum allowable temperature inversely proportional to the cooling water inlet temperature Tt in a range equal to or higher than the second predetermined value. Can more reliably prevent a pressure increase due to an abnormal temperature rise. Further, in order to perform control without causing the heating amount to deviate from the value corresponding to the original cooling load as much as possible, the heating amount suppression unit 10 restricts the heating amount step by step at predetermined time intervals. It is assumed that it is a step limiting means. The operation and effect of the absorption refrigerator configured as described above will be described below. When the cooling water temperature detected by the first temperature detecting means 7 is low, the maximum allowable temperature of the high temperature generator 3 is set lower by the limit temperature setting means 9 than when the cooling water temperature is high. During the steady operation under the condition of the low cooling water temperature, the amount of heating in the high temperature generator 3 can be suppressed even with the cooling load of the same temperature as compared with the case where the cooling water temperature is high. As long as the temperature of the high-temperature generator 3 detected by the above exceeds the maximum allowable temperature set low, the heating amount is reduced by the heating amount suppressing means 10, so that the excess refrigerating capacity can be suppressed and energy saving can be achieved. I can do it. Moreover, even when the temperature of the cooling water is low, if the temperature of the high-temperature generator 3 does not easily exceed the maximum allowable temperature, for example, when starting up the operation, the high-temperature generator 3 can be used in response to a large cooling load.
Since a sufficient amount of heating can be ensured, the responsiveness can also be improved. Further, even when the cooling water temperature is high, the heating amount is reduced by the heating amount suppressing means 10 as long as the temperature of the high temperature generator 3 exceeds the maximum allowable temperature. Can be avoided. In addition, as long as the temperature of the high-temperature generator 3 exceeds the maximum allowable temperature regardless of the level of the cooling water, the heating amount is reduced by the heating amount suppressing means 10, so that a large amount of hydrogen gas is generated. When an abnormal situation occurs, the pressure in the high-temperature generator 3 can be prevented from increasing. Particularly, in the present invention, since the suppression control of the heating amount is performed based on the temperature of the high-temperature generator 3 instead of the temperature of the low-temperature generator 4, the following advantages are also provided. That is, if the temperature of the high-temperature generator 3 is higher than that of the low-temperature generator 4 and the limit value is determined by the temperature of the low-temperature generator 4 from the start of the operation, the temperature of the high-temperature generator 3 rises abnormally. Sometimes problems arise. In other words, when the pressure of the combustion gas is higher than the design value, or when noncondensable gas (eg, hydrogen) generated by corrosion is accumulated in the machine, the operation should be performed at a pressure lower than the atmospheric pressure. The temperature of the high-temperature generator 3 on the premise of the above may abnormally rise, and the pressure may become higher than the atmospheric pressure. In addition, as the temperature is higher, the corrosiveness of the absorbing solution using the lithium bromide aqueous solution is increased, and there is a fear that the corrosion of the device may progress abnormally. However, in the present invention, since the amount of heating is suppressed based on the temperature of the high-temperature generator 3, these problems can be avoided and appropriate control can be performed. BRIEF DESCRIPTION OF THE FIGURES

【図１】本発明に係る吸収式冷凍機の実施例を示す配管
図。FIG. 1 is a piping diagram showing an embodiment of an absorption refrigerator according to the present invention.

【図２】同制御フローシート。FIG. 2 is a control flow sheet.

【図３】従来例の配管図。FIG. 3 is a piping diagram of a conventional example.

【図４】従来例の制御を示す図。 発明を実施するための最良の形態 図１に示すものは、ガス焚式二重効用形の吸収式冷凍
機であって、冷媒液の散布器12及び冷媒ポンプ13をも
ち、冷媒を蒸発させて冷水管11に冷房負荷に供給する冷
水を取り出す蒸発器１と、該蒸発器１と同一容器20内に
エリミネータ21を挟んで隣接状に設けられ、濃溶液の散
布器22及び冷却水配管23をもち、蒸発器１で蒸発した冷
媒を溶液に吸収させる吸収器２と、該吸収器２と溶液ポ
ンプ６並びに低温熱交換器61及び高温熱交換器62を介し
て接続され、バーナー31aから成る加熱源31により吸収
器２で多量に冷媒を吸収した稀溶液から冷媒を発生させ
る高温発生器３、該高温発生器３で発生する冷媒蒸気を
流す加熱器41をもち、高温発生器３で再生されて高温熱
交換器62を通過した後の中間濃度溶液から冷媒を発生さ
せる低温発生器４と、該低温発生器４と同一容器50内に
設けられ、吸収器２の冷却水配管23の後段に連続して設
ける冷却水配管51により各発生器3,4で発生した冷媒蒸
気を凝縮させる凝縮器５とを備えている。 高温発生器３に具備する前記バーナー31aによる加熱
量は、該バーナー31aへの供給燃料を制御する燃料供給
弁32aから成る加熱量制御手段32によって変更可能とし
ており、前記冷水管11の出口に設ける冷水出口温度検出
手段14から成る冷房負荷検出手段での検出値に基づき、
燃料供給弁32aを開度調節手段32bからの制御で開度調節
し、これにより、冷房負荷の大小に応じてその加熱量を
増減制御するようにしている。因に、冷水管11に取り出
す冷水の設定温度を例えば７℃とした場合の具体的な一
例を示すと、図２中に示すように、冷水出口温度検出手
段14で検出する冷水温度Tmが７℃以下のときは燃料制御
弁32aの開度を０％にして燃焼を停止し、冷水温度Tmが1
2℃以上のときは100％の開度にして定格燃焼を行い、７
℃〜12℃の中間域は比例制御を行うのである。 尚、冷房負荷の検出手段は、冷水出口温度検出手段14
で構成する他、冷水管11の出入口に設ける冷水出入口温
度差検出手段で構成してもよい。 以上の構成において、図１及び図２に示すように、吸
収器２に配管する冷却水配管23に流す冷却水の入口温度
Ttを検出する第一温度検出手段７と、高温発生器３の温
度Tghを検出する第二温度検出手段８とを設け、これら
温度検出手段7,8を、前記冷水出口温度検出器14と同
様、前記開度調節手段32bを具備するコントローラ100に
入力させる。尚、このコントローラ100はマイクロコン
ピュータ等を用いて構成するものである。 更に、第一温度検出手段７の検出値の大小に応じて高
温発生器３の最高許容温度の高低を定める限界温度設定
手段９を設ける。この場合、限界温度設定手段９は、第
一温度検出手段７で検出する冷却水入口温度Ttが、所定
値よりも低い範囲では、該冷却水入口温度Ttに比例した
最高許容温度とし、所定値以上の範囲では、一定の最高
許容温度とするものとするのが好ましく、具体的には、
例えば図２に示すように、第一温度検出手段７で検出す
る冷却水入口温度Ttが19℃のときはその最高許容温度を
142℃に、冷却水入口温度Ttが32℃以上のときは155℃一
定に、19℃〜32℃の中間域は比例的に変化する値に設定
するのである。また、例えば、冷却水入口温度Ttが20℃
のときはその最高許容温度を120℃に、20℃〜32℃の範
囲では比例的に変化して32℃のときはその最高許容温度
を162℃に、32℃〜34℃の範囲では162℃に一定とし、32
℃以上の範囲では反比例して例えば40℃のときは155℃
になるように、すなわち、限界温度設定手段９は、第一
温度検出手段７で検出する冷却水入口温度Ttが、第１の
所定値よりも低い範囲では、該冷却水入口温度Ttに比例
した最高許容温度とし、前記第１の所定値以上で且つこ
れよりも高い第２の所定値よりも低い範囲では、一定の
最高許容温度とし、第２の所定値以上の範囲では、冷却
水入口温度Ttに反比例した最高許容温度とするものとす
るのも好ましい。 次に、第二温度検出手段８の検出値が前記限界温度設
定手段９で設定する最高許容温度を越えることになると
き、本来の冷水出口温度に基づく開度よりも小さな開度
を燃料制御弁32aに与える加熱量抑制手段10を設ける。
具体的には、図２に明示するように、燃料制御弁32aを
開度変更させる例えば10秒間程度の最小インターバルを
計時する制御タイマーがタイムアップしたとき、温度検
出手段８の検出値Tghが限界温度設定手段９で設定した
最高許容温度を越えるか否かを判定し、越えることにな
るときには、燃料制御弁32aの開度を例えば10％絞るこ
とによりバーナー31aによる加熱量を減少させるのであ
る。このように、加熱量抑制手段10を、所定間隔毎にそ
の加熱量を一ステップずつ段階的に制限していくものと
する他、一度にその加熱量をゼロにして燃焼を停止させ
るようにしてもよい。 こうして、以上の構成により、第一温度検出手段７で
検出する冷却水温が低い場合の定常運転時には、冷却水
温が高い場合よりも低く定められた最高許容温度を越え
ることとなる限りにおいて、加熱量抑制手段10によりそ
の加熱量が減らされるため、過剰冷凍能力を抑制でき、
省エネが図れるのであるし、又、この冷却水温が低い場
合にも、運転の立上げ時等、高温発生器３の温度が最高
許容温度をなかなか越えない場合には、大きな冷房負荷
に対応して高温発生器３での加熱量を十分に確保できる
ため、応答性を高めることもできるのである。更に、冷
却水温が高い場合は勿論のこと、多量の水素ガス発生時
等の異常事態発生時にも、高温発生器３の温度が最高許
容温度を越えることとなる限りにおいて、加熱量抑制手
段10によりその加熱量が減らされるため、高温発生器３
での圧力高及び過剰濃縮を回避できるのである。 尚、以上の実施例では、加熱源31にバーナー31aを用
いたが、加熱蒸気を用いるものでもよい。 産業上の利用可能性 以上のように、本発明にかかる吸収式冷凍機は、主に
冷媒に水を、吸収溶液に臭化リチウム水溶液をそれぞれ
用い、構成機器として、蒸発器、吸収器、高温発生器、
低温発生器及び凝縮器を備える二重効用形の吸収式冷凍
機に有用である。FIG. 4 is a diagram showing control of a conventional example. BEST MODE FOR CARRYING OUT THE INVENTION FIG. 1 shows a gas-fired double-effect absorption refrigerator having a refrigerant liquid sprayer 12 and a refrigerant pump 13 for evaporating refrigerant. An evaporator 1 for taking out cold water to be supplied to a cooling load to the cold water pipe 11 is provided adjacent to the evaporator 1 with the eliminator 21 interposed therebetween in the same container 20. An absorber 2 for absorbing the refrigerant evaporated in the evaporator 1 into a solution, and a heating pump connected to the absorber 2 via a solution pump 6 and a low-temperature heat exchanger 61 and a high-temperature heat exchanger 62 and comprising a burner 31a. A high-temperature generator 3 for generating a refrigerant from a dilute solution in which a large amount of the refrigerant has been absorbed by the absorber 2 by the source 31 and a heater 41 for flowing the refrigerant vapor generated by the high-temperature generator 3 are reproduced by the high-temperature generator 3. Refrigerant from the intermediate-concentration solution after passing through the high-temperature heat exchanger 62 The low-temperature generator 4 to be generated and the cooling water pipe 51 provided in the same container 50 as the low-temperature generator 4 and provided at the subsequent stage of the cooling water pipe 23 of the absorber 2 and generated by each of the generators 3 and 4 A condenser 5 for condensing the refrigerant vapor. The amount of heating by the burner 31a provided in the high temperature generator 3 can be changed by a heating amount control means 32 including a fuel supply valve 32a for controlling fuel supplied to the burner 31a, and is provided at an outlet of the cold water pipe 11. Based on the value detected by the cooling load detection means comprising the chilled water outlet temperature detection means 14,
The opening of the fuel supply valve 32a is adjusted by the control of the opening adjusting means 32b, whereby the heating amount is controlled to increase or decrease according to the magnitude of the cooling load. Incidentally, a specific example in which the set temperature of the chilled water taken out to the chilled water pipe 11 is set to, for example, 7 ° C. As shown in FIG. 2, the chilled water temperature Tm detected by the chilled water outlet temperature detecting means 14 is 7 ° C. When the temperature is lower than 0 ° C., the opening of the fuel control valve 32a is set to 0% to stop the combustion, and the chilled water temperature Tm becomes 1
When the temperature is 2 ° C or higher, the rated combustion is performed with 100% opening.
In the middle range between 12 ° C and 12 ° C, proportional control is performed. The cooling load detecting means is a chilled water outlet temperature detecting means 14.
Alternatively, it may be configured by a chilled water inlet / outlet temperature difference detecting means provided at the inlet / outlet of the chilled water pipe 11. In the above configuration, as shown in FIGS. 1 and 2, the inlet temperature of the cooling water flowing through the cooling water pipe 23 connected to the absorber 2
A first temperature detecting means 7 for detecting Tt and a second temperature detecting means 8 for detecting the temperature Tgh of the high temperature generator 3 are provided. These temperature detecting means 7 and 8 are similar to the cold water outlet temperature detector 14. Is input to the controller 100 including the opening degree adjusting means 32b. Note that the controller 100 is configured using a microcomputer or the like. Further, a limit temperature setting means 9 for determining the maximum allowable temperature of the high temperature generator 3 according to the magnitude of the detection value of the first temperature detection means 7 is provided. In this case, when the cooling water inlet temperature Tt detected by the first temperature detecting means 7 is lower than a predetermined value, the limit temperature setting means 9 sets the maximum allowable temperature in proportion to the cooling water inlet temperature Tt to a predetermined value. In the above range, it is preferable to set a certain maximum allowable temperature, specifically,
For example, as shown in FIG. 2, when the cooling water inlet temperature Tt detected by the first temperature detecting means 7 is 19 ° C., the maximum allowable temperature is
When the cooling water inlet temperature Tt is equal to or higher than 32 ° C., the temperature is set to 155 ° C., and the intermediate range of 19 ° C. to 32 ° C. is set to a value that changes proportionally. Further, for example, when the cooling water inlet temperature Tt is 20 ° C.
The maximum allowable temperature changes to 120 ° C in the case of, the maximum allowable temperature changes to 162 ° C in the range of 20 ° C to 32 ° C and 32 ° C to 162 ° C in the range of 32 ° C to 34 ° C. Constant and 32
In the range above ℃, inversely proportional, for example, 155 ℃ at 40 ℃
That is, the limit temperature setting means 9 is proportional to the cooling water inlet temperature Tt in a range where the cooling water inlet temperature Tt detected by the first temperature detecting means 7 is lower than the first predetermined value. The maximum allowable temperature is a constant maximum allowable temperature in a range equal to or higher than the first predetermined value and lower than a second predetermined value higher than the first predetermined value, and a cooling water inlet temperature is set in a range equal to or higher than the second predetermined value. It is also preferable to set the maximum allowable temperature in inverse proportion to Tt. Next, when the detected value of the second temperature detecting means 8 exceeds the maximum allowable temperature set by the limit temperature setting means 9, the fuel control valve sets an opening smaller than the opening based on the original chilled water outlet temperature. The heating amount suppressing means 10 applied to 32a is provided.
Specifically, as clearly shown in FIG. 2, when the control timer for measuring the minimum interval of, for example, about 10 seconds for changing the opening of the fuel control valve 32a has timed out, the detection value Tgh of the temperature detecting means 8 has reached the limit. It is determined whether or not the temperature exceeds the maximum allowable temperature set by the temperature setting means 9. If the temperature exceeds the maximum allowable temperature, the amount of heating by the burner 31a is reduced by reducing the opening of the fuel control valve 32a by, for example, 10%. As described above, the heating amount suppressing means 10 is configured to limit the heating amount step by step at predetermined intervals, and to stop the combustion by zeroing the heating amount at a time. Is also good. Thus, with the above-described configuration, the amount of heating during normal operation when the cooling water temperature detected by the first temperature detection means 7 is lower than the maximum allowable temperature set lower than when the cooling water temperature is higher than when the cooling water temperature is high is increased. Since the heating amount is reduced by the suppression means 10, the excess refrigeration capacity can be suppressed,
Energy saving can be achieved, and even when the cooling water temperature is low, if the temperature of the high-temperature generator 3 does not easily exceed the maximum allowable temperature, such as when starting up the operation, it is necessary to cope with a large cooling load. Since the heating amount in the high-temperature generator 3 can be sufficiently secured, the responsiveness can be improved. Further, not only when the cooling water temperature is high, but also when an abnormal situation such as generation of a large amount of hydrogen gas occurs, as long as the temperature of the high-temperature generator 3 exceeds the maximum allowable temperature, the heating amount suppressing means 10 Since the heating amount is reduced, the high-temperature generator 3
Pressure and over-concentration in the system can be avoided. In the above-described embodiment, the burner 31a is used as the heating source 31, but a heating steam may be used. INDUSTRIAL APPLICABILITY As described above, the absorption refrigerator according to the present invention mainly uses water as a refrigerant and an aqueous solution of lithium bromide as an absorption solution, and includes an evaporator, an absorber, and a high temperature as constituent components. Generator,
It is useful for a double effect absorption refrigerator having a low temperature generator and a condenser.

Claims (8)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】冷媒を蒸発させて冷房負荷に供給する冷熱
を取り出す蒸発器（１）、該蒸発器（１）で蒸発した冷
媒を溶液に吸収させる吸収器（２）、該吸収器（２）で
冷媒を吸収した溶液から冷媒を発生させる高温発生器
（３）及び低温発生器（４）、これら発生器（3,4）で
発生した冷媒を凝縮させる凝縮器（５）を備え、冷房負
荷の大小に応じて前記高温発生器（３）に具備する加熱
源（31）の加熱量を増減制御する加熱量制御手段（32）
を設けた吸収式冷凍機において、前記吸収器（２）に配
管する冷却水配管（23）に流す冷却水の温度を検出する
第一温度検出手段（７）と、前記高温発生器（３）の温
度を検出する第二温度検出手段（８）と、前記第一温度
検出手段（７）の検出値の大小に応じて前記高温発生器
（３）の最高許容温度の高低を定める限界温度設定手段
（９）と、前記第二温度検出手段（８）の検出値が前記
限界温度設定手段（９）で設定する最高許容温度を越え
ることになるとき前記加熱量制御手段（32）に加熱量の
減少指令を与える加熱量抑制手段（10）とを設けたこと
を特徴とする吸収式冷凍機。An evaporator (1) for evaporating a refrigerant to extract cold heat supplied to a cooling load, an absorber (2) for absorbing the refrigerant evaporated by the evaporator (1) into a solution, and an absorber (2). A) a high-temperature generator (3) and a low-temperature generator (4) for generating a refrigerant from a solution that has absorbed the refrigerant in (1), and a condenser (5) for condensing the refrigerant generated in these generators (3, 4). Heating amount control means (32) for increasing or decreasing the heating amount of a heating source (31) provided in the high-temperature generator (3) according to the magnitude of the load;
A first temperature detecting means (7) for detecting a temperature of cooling water flowing through a cooling water pipe (23) connected to the absorber (2); and the high temperature generator (3). A second temperature detecting means (8) for detecting the temperature of the first temperature detecting means, and a limit temperature setting for determining the maximum allowable temperature of the high temperature generator (3) according to the magnitude of the detection value of the first temperature detecting means (7). Means (9) and the heating amount control means (32) when the detected value of the second temperature detecting means (8) exceeds the maximum allowable temperature set by the limit temperature setting means (9). An absorption type refrigerator provided with a heating amount suppressing means (10) for giving a command to reduce the amount of heat. 【請求項２】加熱源（31）がバーナー（31a）であり、
加熱量制御手段（32）がバーナー（31a）への燃料供給
を開度調節により制御する燃料制御弁（32a）である請
求の範囲第１項記載の吸収式冷凍機。2. The heating source (31) is a burner (31a),
The absorption refrigerator according to claim 1, wherein the heating amount control means (32) is a fuel control valve (32a) for controlling fuel supply to the burner (31a) by adjusting an opening degree. 【請求項３】冷房負荷の検出手段が、蒸発器（１）に配
管する冷水管（11）の出口に設ける冷水出口温度検出手
段（14）である請求の範囲第１項又は第２項記載の吸収
式冷凍機。3. A cooling water outlet temperature detecting means (14) provided at an outlet of a chilled water pipe (11) piped to an evaporator (1). Absorption refrigerator. 【請求項４】冷房負荷の検出手段が、蒸発器（１）に配
管する冷水管（11）に流す冷水の出入口温度差を検出す
る冷水出入口温度差検出手段である請求の範囲第１項又
は第２項記載の吸収式冷凍機。4. A cooling water inlet / outlet temperature difference detecting means for detecting an inlet / outlet temperature difference of chilled water flowing through a chilled water pipe (11) connected to an evaporator (1). 3. The absorption refrigerator according to claim 2. 【請求項５】第一温度検出手段（７）が、吸収器（２）
に配管する冷却水配管（23）に流す冷却水の入口温度
（Tt）を検出する冷却水入口温度検出手段である請求の
範囲第１項記載の吸収式冷凍機。5. A method according to claim 1, wherein said first temperature detecting means comprises an absorber.
2. The absorption chiller according to claim 1, wherein the cooling chiller is a cooling water inlet temperature detecting means for detecting an inlet temperature (Tt) of cooling water flowing through a cooling water pipe (23). 【請求項６】限界温度設定手段（９）は、第一温度検出
手段（７）で検出する冷却水入口温度（Tt）が、所定値
よりも低い範囲では、該冷却水入口温度（Tt）に比例し
た最高許容温度とし、所定値以上の範囲では、一定の最
高許容温度とするものである請求の範囲第５項記載の吸
収式冷凍機。6. The cooling water inlet temperature (Tt) when the cooling water inlet temperature (Tt) detected by the first temperature detecting means (7) is lower than a predetermined value. 6. The absorption refrigerator according to claim 5, wherein a maximum allowable temperature is set in proportion to the maximum allowable temperature, and a predetermined maximum allowable temperature is set in a range equal to or higher than a predetermined value. 【請求項７】限界温度設定手段（９）は、第一温度検出
手段（７）で検出する冷却水入口温度（Tt）が、第１の
所定値よりも低い範囲では、該冷却水入口温度（Tt）に
比例した最高許容温度とし、前記第１の所定値以上で且
つこれよりも高い第２の所定値よりも低い範囲では、一
定の最高許容温度とし、第２の所定値以上の範囲では、
冷却水入口温度（Tt）に反比例した最高許容温度とする
ものである請求の範囲第５項記載の吸収式冷凍機。7. The cooling water inlet temperature (Tt) detected by the first temperature detecting means (7) is lower than a first predetermined value if the cooling water inlet temperature (Tt) is lower than a first predetermined value. The maximum allowable temperature is proportional to (Tt). In a range that is equal to or higher than the first predetermined value and lower than a second predetermined value that is higher than the first predetermined value, the maximum allowable temperature is set to be a certain maximum allowable temperature and a range that is equal to or higher than a second predetermined value. Then
6. The absorption refrigerator according to claim 5, wherein the maximum allowable temperature is inversely proportional to the cooling water inlet temperature (Tt). 【請求項８】加熱量抑制手段（10）は、所定時間毎に加
熱量を一ステップずつ段階的に制限していくステップ制
限手段である請求の範囲第１項又は第２項若しくは請求
の範囲第５項又は第６項若しくは第７項記載の吸収式冷
凍機。8. The heating means according to claim 1, wherein said heating amount suppressing means is a step limiting means for limiting the heating amount step by step at predetermined time intervals. Item 8. The absorption refrigerator according to item 5, 6 or 7.