JPH07190504A - Refrigerant flow rate controller - Google Patents

Abstract

PURPOSE:To obtain signals with less time delay, ensure effectual and smooth operation, and control many branch flow passages with reduced controllers by providing a first sensor in the vicinity of an entrance of each flow passage, a second sensor backwardly of the same flow passage, and a third sensor in a common final end region of a plurality of the passages. CONSTITUTION:A refrigerant from a freezer enters a distributer 2 through a flow rate control valve 1 from a liquid pipe 8, and is thereafter collected into an assembly pipe 4 after heat exchange through three flow passages 3-1, 3-2, and 3-3 in an evaporator and is returned to the freezer from a gas recovery pipe 9. There are mounted a first sensor 5 in the vicinity of an entrance of the refrigerant flow passage 3-3, a second sensor 6 intermediate between the flow passages 3-1 and 3-3, and a third sensor 7 at the assembly pipe 4. A difference between an output of the first sensor 5 and the total sum of outputs of the second and third sensors 6, 7 is used for estimation to control the refrigerant flow rate. For this, in the flow rate control of the refrigerant flowing through many branches the entire control is ensured with a reduced number of control units.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は冷却装置において効率が
高くかつ安全性の高い運転を可能とする制御方法を与え
るものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a control method which enables highly efficient and safe operation of a cooling device.

【０００２】[0002]

【従来の技術】冷却装置の運転において適正な過熱度で
運転する事が効率、安全性の両面から重要である事は周
知の事であり、この目的の為圧力、温度等を検知して過
熱度に相当する信号を得て、これにより冷媒流量制御を
行う事は広く行われていた。しかし従来は蒸発器の出入
口に相当する２つの部位より得た情報のみから過熱度に
相当する信号を得る構成であった。2. Description of the Related Art It is well known that it is important to operate a cooling device at an appropriate degree of superheat in terms of efficiency and safety. For this purpose, it is necessary to detect pressure, temperature, etc. It has been widely practiced to obtain a signal corresponding to the temperature and control the refrigerant flow rate by this. However, in the past, a signal corresponding to the degree of superheat was obtained only from the information obtained from the two parts corresponding to the inlet and outlet of the evaporator.

【０００３】ところが一般に蒸発器内の冷媒流路は多岐
に分岐している為、これらにそれぞれセンサーと制御装
置を設けない限り分岐による各流路のアンバランスを補
正する事が出来なかった。However, since the refrigerant flow passages in the evaporator are generally divergent, it is impossible to correct the imbalance of the respective passages due to the divergence unless a sensor and a control device are provided for each of them.

【０００４】又、出口側センサー位置も効率と安全性と
に関し相反する関係を持っている為、どうしても効率を
犠牲にして安全側を選ぶか、制御目標設定時に安全度を
大きく取った設定とする事となっていた。Further, since the exit side sensor position also has a contradictory relationship with respect to efficiency and safety, the safety side is inevitably selected at the expense of efficiency, or the safety degree is set to be large when setting the control target. It was a thing.

【０００５】更に、安全性確保の為、出口側センサーを
複数流路が集合した後の共通部分に取る事が行われてい
たが、この場合信号の時間遅れが大きく成りハンチング
の原因となる等の欠点があった。Further, in order to ensure safety, the exit side sensor is taken to be a common part after a plurality of flow paths have been gathered, but in this case, the signal time delay becomes large and causes hunting. There was a drawback.

【０００６】[0006]

【発明が解決しようとする課題】時間遅れの少ない信号
を得て、滑らかかつ効率の良い動作が行え、かつ多岐に
分岐した被制御系の流路に対し、より少ない数の制御装
置でこれを制御可能とする事である。SUMMARY OF THE INVENTION A signal with a small time delay can be obtained, smooth and efficient operation can be performed, and this can be performed with a smaller number of control devices for the flow paths of the controlled system that are diverged in various ways. It should be controllable.

【０００７】[0007]

【発明が解決する為の手段】時間遅れの少ない信号を得
る為に、入口側センサーを取り付けた流路の中間の至出
口近傍に第２のセンサーを設けた。これにより他の系の
影響を受ける事なく直接的に制御結果を反映した信号を
早めに取り込む事が出来る。In order to obtain a signal with a small time delay, a second sensor is provided in the middle of the flow path to which the inlet side sensor is attached, in the vicinity of the outlet. As a result, a signal directly reflecting the control result can be taken in early without being affected by other systems.

【０００８】しかしこれだけではセンサーのない他の流
路で起こっている事を知る事が出来ず危険性が有る。However, it is not possible to know what is happening in other flow paths without sensors by this alone, which is dangerous.

【０００９】そこで本発明は複数流路の共通終端部域に
第３のセンサーを設ける事でこの問題を解決した。Therefore, the present invention solves this problem by providing a third sensor in the common terminal area of the plurality of flow paths.

【００１０】[0010]

【実施例】図１は本発明の実施例を模式的に示す蒸発器
周辺の図で、図示しない冷凍機よりの冷媒は液管８より
膨張弁を兼ねる流量制御弁１を介してディストリビュー
ター２に入り、この後蒸発器内で３−１、３−２、３−
３の３本の流路でそれぞれ熱交換後集合管４に集まり、
ガス回収管９より冷凍機に戻される。1 is a schematic view of an evaporator according to an embodiment of the present invention, in which a refrigerant from a refrigerator (not shown) is delivered from a liquid pipe 8 via a flow control valve 1 which also serves as an expansion valve and a distributor 2 Then, after this, in the evaporator 3-1, 3-2, 3-
After heat exchange in the three flow paths of 3, each gathers in the collecting pipe 4,
It is returned to the refrigerator through the gas recovery pipe 9.

【００１１】本実施例では３−３の入口部近傍に第１の
センサー５、中間部に第２のセンサー６、集合管部に第
３のセンサー７が取り付けられている。In this embodiment, a first sensor 5 is attached near the inlet 3-3, a second sensor 6 is attached in the middle, and a third sensor 7 is attached to the collecting pipe.

【００１２】尚、第１のセンサー５、第２のセンサー
６、第３のセンサー７はその電気的結線を示す図２の通
り。The first sensor 5, the second sensor 6, and the third sensor 7 are electrically connected as shown in FIG.

【００１３】第１のセンサー５は２組の熱電対が同極性
直列接続されたもので、第２のセンサー６と第３のセン
サー７とは各１組の熱電対が同極性直列接続されてい
る。The first sensor 5 has two thermocouples connected in series with the same polarity, and the second sensor 6 and the third sensor 7 each have one set of thermocouples connected in series with the same polarity. There is.

【００１４】又、全体としては第１のセンサー５と第２
のセンサー６及び第３のセンサー７とは逆極性直列接続
されて、本実施例の信号源となっている。Also, as a whole, the first sensor 5 and the second sensor 5
The sensor 6 and the third sensor 7 are connected in series in reverse polarity and serve as a signal source of this embodiment.

【００１５】本発明は前述の通り構成されているので、
第１のセンサー５により略入口近傍における冷媒蒸発温
度、第２のセンサー６によりその時点での熱交換の状
況、第３のセンサー７により３−３の流路のみならず３
−１及び３−２の流路においても冷媒液過剰状態に成っ
ていないかどうか等を反映した信号を得る事が出来る。Since the present invention is constructed as described above,
The first sensor 5 causes the refrigerant vaporization temperature in the vicinity of the inlet, the second sensor 6 causes heat exchange at that time, and the third sensor 7 causes not only the flow path 3-3 but also 3
It is possible to obtain a signal that reflects whether or not the refrigerant liquid is in the excess state in the flow paths -1 and 3-2.

【００１６】すなわちセンサーの取り付けられていない
流路３−１、又は流路３−２が流路３−３より先に冷媒
過剰（液バック）状態に成った場合、第３のセンサー７
の検知する温度から冷媒過剰状態である事を知る事が出
来るので、安全でありかつ通常第３のセンサー７が冷媒
過剰状態を検知する前に、第２のセンサー６が冷媒流路
内の相当部分に冷媒が充満して来た事を検知するので、
全体としてのセンサーの検知する過熱度相当信号の微分
値変化を利用する事で時間遅れを大幅に減少した制御が
可能となる。That is, when the flow passage 3-1 to which no sensor is attached or the flow passage 3-2 is in the refrigerant excess (liquid back) state before the flow passage 3-3, the third sensor 7
Since it is possible to know that the refrigerant is in the excessive refrigerant state from the temperature detected by the second sensor 6, it is safe and normally before the third sensor 7 detects the excessive refrigerant state, the second sensor 6 corresponds to the inside of the refrigerant passage. Since it detects that the part is filled with refrigerant,
By using the change in the differential value of the superheat equivalent signal detected by the sensor as a whole, control with significantly reduced time delay becomes possible.

【００１７】これらの特徴は各センサー信号の単純な和
及び差信号でありながら流路内圧力損失の関係で、冷媒
に接した時の各部の温度が、第３のセンサー７、第２の
センサー６、第１のセンサー５の順に差の有る事を巧み
に利用した結果である。These characteristics are simple sum and difference signals of the respective sensor signals, but due to the pressure loss in the flow channel, the temperature of each part when in contact with the refrigerant is determined by the third sensor 7 and the second sensor. This is a result of skillfully utilizing the fact that there is a difference in the order of 6 and the first sensor 5.

【００１８】以上最も簡単に構成出来る熱電対を組み合
わせたセンサーによる実施例について説明したが、基本
的には同一流路系にあって前後し圧力損失の異なる位置
の温度を検出する第１、第２のセンサー及び更に後方に
あって少なくともその制御ユニットが受け持つ流路系の
共通帰路に第３のセンサーを設け、これら３個所の位置
の温度信号より演算する事で制御するものである。Although the embodiment using the sensor in which the thermocouples which can be most simply constructed are combined has been described above, basically, the first and the first for detecting the temperature at the positions in the same flow path system and having different pressure losses in front and back. The third sensor is provided in the common return path of the flow path system, which is located at the rear of the two sensors and at least the control unit, and controls by calculating temperature signals at these three positions.

【００１９】従ってそのセンサーは更に精度を高める
為、白金抵抗体等を用いてもよい事はいうまでもない。Therefore, it goes without saying that a platinum resistor or the like may be used in order to further improve the accuracy of the sensor.

【００２０】又、センサーの構成、演算過程において、
いずれかの位置よりの信号に比重を持たせる為、いずれ
かを数倍にしたり、センサーを追加して取り付けたりす
る事が良い結果をもたらす場合もある。Further, in the configuration of the sensor and the calculation process,
In order to give specific gravity to the signal from any one of the positions, it is sometimes possible to multiply one of them or add an additional sensor to bring good results.

【００２１】[0021]

【発明の効果】以上説明したように本発明の冷媒流量制
御装置は、蒸発器内で多岐に分岐して流れる冷媒の流量
制御において、少数の制御ユニットで全体の制御を行い
ながら安全性を確保しつつ高効率の運転が行えるもので
ある。As described above, in the refrigerant flow rate control device of the present invention, in controlling the flow rate of the refrigerant that branches and flows in the evaporator in various ways, a small number of control units perform overall control while ensuring safety. The operation can be performed with high efficiency.

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

【図１】本発明の実施例を模式的に示す蒸発器周辺の
図。FIG. 1 is a diagram around an evaporator schematically showing an embodiment of the present invention.

【図２】本発明の実施例におけるセンサーの構成を示す
電気的結線図FIG. 2 is an electrical connection diagram showing a configuration of a sensor according to an embodiment of the present invention.

【符号の説明】[Explanation of symbols]

１ 膨張弁を兼ねる流量制御弁 ２ ディストリビューター ３−１ 蒸発器を構成する冷媒流路 ３−２ 蒸発器を構成する冷媒流路 ３−３ 蒸発器を構成する冷媒流路 ４ 集合管 ５ 第１のセンサー ６ 第２のセンサー ７ 第３のセンサー ８ 液管 ９ ガス回収管 1 Flow rate control valve which also serves as an expansion valve 2 Distributor 3-1 Refrigerant flow path which constitutes an evaporator 3-2 Refrigerant flow path which constitutes an evaporator 3-3 Refrigerant flow path which constitutes an evaporator 4 Collection pipe 5 1st Sensor 6 Second sensor 7 Third sensor 8 Liquid pipe 9 Gas recovery pipe

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 一つの制御出力信号で流量を制御される
冷媒が蒸発器内で複数の流路を通るよう構成されている
冷却装置において、冷媒流路の温度に係る信号を得る
為、第１のセンサーを該流路の入口近傍、第２のセンサ
ーを第１のセンサーが取付られたと同一流路の後方、第
３のセンサーを複数の流路の共通終端部域に設け、第１
のセンサーの出力と、第２、第３のセンサーの出力の和
との差を用いて演算を行い、冷媒流量を制御する事を特
徴とする冷媒流量制御装置。1. A cooling device in which a refrigerant whose flow rate is controlled by one control output signal is configured to pass through a plurality of flow paths in an evaporator, in order to obtain a signal related to the temperature of the refrigerant flow path. The first sensor is provided in the vicinity of the inlet of the flow path, the second sensor is provided behind the same flow path where the first sensor is attached, and the third sensor is provided in the common terminal area of the plurality of flow paths.
The refrigerant flow rate control device characterized in that the refrigerant flow rate is controlled by performing calculation using the difference between the output of the sensor and the output of the second and third sensors. 【請求項２】 第１のセンサーとして２組の熱電対を順
極性直列接続したものを用い、第２、第３のセンサーと
して各１組の熱電対を用い同じく順極性直列接続すると
共に、第１のセンサーと第２、第３のセンサーを逆極性
直列接続してその両端より温度差に係る信号を得る事を
特徴とする請求項１の冷媒流量制御装置。2. A pair of thermocouples in which two pairs of thermocouples are connected in a forward polarity series are used as the first sensor, and a pair of thermocouples in each pair is used as a second and a third sensor. 2. The refrigerant flow rate control device according to claim 1, wherein the first sensor and the second and third sensors are connected in series of opposite polarities to obtain a signal relating to the temperature difference from both ends thereof.