JPH04203866A - Refrigerant shortage detector for cooling device - Google Patents

Refrigerant shortage detector for cooling device

Info

Publication number
JPH04203866A
JPH04203866A JP33706490A JP33706490A JPH04203866A JP H04203866 A JPH04203866 A JP H04203866A JP 33706490 A JP33706490 A JP 33706490A JP 33706490 A JP33706490 A JP 33706490A JP H04203866 A JPH04203866 A JP H04203866A
Authority
JP
Japan
Prior art keywords
refrigerant
compressor
sensor
refrigerant shortage
gas
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.)
Pending
Application number
JP33706490A
Other languages
Japanese (ja)
Inventor
Shunji Komatsu
小松　俊二
Susumu Kurihara
将 栗原
Kazumitsu Kobayashi
小林　一光
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Unisia Automotive Ltd
Sanden Corp
Original Assignee
Japan Electronic Control Systems Co Ltd
Sanden Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Japan Electronic Control Systems Co Ltd, Sanden Corp filed Critical Japan Electronic Control Systems Co Ltd
Priority to JP33706490A priority Critical patent/JPH04203866A/en
Priority to EP19910311098 priority patent/EP0488775A3/en
Publication of JPH04203866A publication Critical patent/JPH04203866A/en
Pending legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/005—Arrangement or mounting of control or safety devices of safety devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/006—Fluid-circulation arrangements optical fluid control arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2500/00—Problems to be solved
    • F25B2500/22—Preventing, detecting or repairing leaks of refrigeration fluids
    • F25B2500/222—Detecting refrigerant leaks

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Air-Conditioning For Vehicles (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)

Abstract

PURPOSE:To stop the operation of a compressor when refrigerant in a circulating circuit has become short by a method wherein a refrigerant shortage detecting sensor, detecting the gas and liquid mixing condition of refrigerant and outputting an electric signal for opening a power supply circuit for driving a compressor, is provided in a refrigerant conducting pipe at the high-pressure side in the refrigerant circulating circuit of a cooling device. CONSTITUTION:One terminal of a refrigerant shortage sensor 9 is connected to a power supply while the other terminal of the same is grounded through an amplifier 11 and the solenoid coil 12 of an electromagnetic opening and closing switch 10. An optical sensor is employed in a refrigerant shortage sensor 9 which detects the mixing ratio of gas and liquid of the refrigerant based on the amount of permeation of light. When the refrigerant becomes short, the ratio of mixing of gas to liquid is increased whereby the refrigerant shortage sensor 9 detects it and outputs an electric signal amplified by an amplifier 11. According to the conduction of the electric current, the solenoid coil 12 is excited and an automatic opening and closing switch 10 is put OFF. Accordingly, the driving power supply circuit of a compressor 2 is opened and the operation of the compressor 2 is stopped. For your reference, a self heat generating type thermistor can be used instead of the optical sensor.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は、冷却装置内の冷媒が不足した際に、冷媒圧縮
用のコンプレッサの稼働を停止させるための冷媒不足検
出装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a refrigerant shortage detection device for stopping the operation of a compressor for compressing refrigerant when there is a shortage of refrigerant in a cooling device.

（従来の技術） 従来の冷却装置の冷媒不足検出装置を第３図に示す。同
図において、冷却装置の冷媒の循環回路１は、コンプレ
ッサ２、コンデンサ３、レシーバドライヤ４、膨張弁５
及びエバポレート６が冷媒流通管７により順次ループ状
に接続されている。(Prior Art) A conventional refrigerant shortage detection device for a cooling device is shown in FIG. In the figure, a refrigerant circulation circuit 1 of a cooling device includes a compressor 2, a condenser 3, a receiver dryer 4, and an expansion valve 5.
and evaporator 6 are sequentially connected in a loop through a refrigerant flow pipe 7.

そして、この循環回路１の高子側では冷媒か液化状態で
、また低圧側では気化状態で循環している。。The refrigerant circulates in a liquefied state on the high-pressure side of the circulation circuit 1, and in a vaporized state on the low-pressure side. .

ここで、従来の冷媒不足検出装置においては、循環回路
１の高圧側の流通管７に低圧スイッチ８が設けられ、こ
の低圧スイッチ８がコンプレ・・Ｉす２の駆動電源回路
に電気的に接続されている。この低圧スイッチ８は、流
通管７内の冷媒の圧力が所定の値以下になった場合にＯ
ＦＦするようになっている。Here, in the conventional refrigerant shortage detection device, a low pressure switch 8 is provided in the flow pipe 7 on the high pressure side of the circulation circuit 1, and this low pressure switch 8 is electrically connected to the drive power circuit of the compressor I2. has been done. This low pressure switch 8 is activated when the pressure of the refrigerant in the flow pipe 7 falls below a predetermined value.
It is designed to be FF.

（発明が解決しようとする課題） 上記従来の冷媒不足検出装置においては、低圧スイッチ
８が動作する圧力が約２　ｋｇ／　ｃｍ２と低く、循環
回路１中の液化状態の冷媒が存在しなくなって初めて動
作するようになっている。従って、冷媒は残っているが
、不足しているような状態では、低圧スイッチ８が動作
せず、依然としてコンプレッサ２が稼働し続けていると
いう事態が生ずる。(Problems to be Solved by the Invention) In the conventional refrigerant shortage detection device described above, the pressure at which the low pressure switch 8 operates is as low as approximately 2 kg/cm2, and the pressure at which the low pressure switch 8 operates is as low as approximately 2 kg/cm2, and the pressure is not detected until the liquefied refrigerant in the circulation circuit 1 is no longer present. It's supposed to work. Therefore, in a situation where refrigerant remains but is insufficient, a situation occurs in which the low pressure switch 8 does not operate and the compressor 2 continues to operate.

このような場合、冷却装置の冷却効果か得られないばか
りでなく、コンプレッサ２に機械的ダメージを与えると
いう問題がある。In such a case, there is a problem that not only the cooling effect of the cooling device cannot be obtained, but also mechanical damage is caused to the compressor 2.

そこで、本発明は、循環回路１内の冷媒か不足したら、
コンプレッサの稼働を停止させる冷媒不足検出装置を提
供することを課題としている。Therefore, in the present invention, if there is a shortage of refrigerant in the circulation circuit 1,
An object of the present invention is to provide a refrigerant shortage detection device that stops the operation of a compressor.

（課題を解決するための手段） 上記課題を解決するために、本発明においては、冷媒が
循環する循環回路１における高圧側の冷媒流通管７に、
冷媒の気液混合状態を感知して、電気信号を出力する冷
媒不足検出センサ９を設け、この冷媒不足検出センサ９
の信号によりコンプレッサ２の駆動用電源回路を開放す
るようにして冷却装置の冷媒不足検出装置を構成した。(Means for Solving the Problems) In order to solve the above problems, in the present invention, in the refrigerant flow pipe 7 on the high pressure side in the circulation circuit 1 in which refrigerant circulates,
A refrigerant shortage detection sensor 9 is provided which senses the gas-liquid mixing state of the refrigerant and outputs an electrical signal.
The refrigerant shortage detection device for the cooling device was constructed in such a way that the driving power supply circuit for the compressor 2 was opened in response to the signal.

（作用） 本発明の冷媒不足検出装置は、循環回路１内の冷媒が不
足して圧力が低下すると、高圧側の冷媒流通管７内で気
液混合状態が生ずる。冷媒の気液混合状態か生ずると、
冷媒不足検出センサ９かこれを感知して電気信号を出力
する。この信号により電磁コイル１２が励磁されて電磁
開閉スイッチ１０か動作し、コンプレッサ２の駆動電源
回路を開く。従って、コンプレッサ２の空運転を防Ｉ卜
することができ、また冷媒の不足状態を知ることができ
る。(Function) In the refrigerant shortage detection device of the present invention, when there is a shortage of refrigerant in the circulation circuit 1 and the pressure decreases, a gas-liquid mixed state occurs in the refrigerant flow pipe 7 on the high pressure side. When a gas-liquid mixture of refrigerant occurs,
A refrigerant shortage detection sensor 9 senses this and outputs an electrical signal. This signal excites the electromagnetic coil 12, operates the electromagnetic switch 10, and opens the drive power circuit of the compressor 2. Therefore, dry running of the compressor 2 can be prevented, and the state of refrigerant shortage can be known.

（実施例） 本発明の実施例を図面について説明する。なお、図中第
２図の従来のものと同一の構成部分には同一の符号を付
して説明を省略する。(Example) An example of the present invention will be described with reference to the drawings. Components in the figure that are the same as those of the conventional one shown in FIG.

第１図において、循環回路１のレシーバドライヤ４と膨
張弁５との間の流通管７には、低圧スイッチ８及び冷媒
不足検出センサ９が設けられている。低圧スイッチ８は
、流通管７内の冷媒の圧力が所定の値以下になったら、
スイッチＯＦＦするようになっている。この低圧スイッ
チ８は、コンプレッサ２の駆動用電源回路中に挿入され
ている。In FIG. 1, a low pressure switch 8 and a refrigerant shortage detection sensor 9 are provided in a flow pipe 7 between a receiver dryer 4 and an expansion valve 5 in a circulation circuit 1. The low pressure switch 8 is activated when the pressure of the refrigerant in the flow pipe 7 becomes below a predetermined value.
The switch is turned off. This low pressure switch 8 is inserted into the power supply circuit for driving the compressor 2.

また、この電源回路には電磁開閉スイッチ１０か挿入さ
れている。Further, an electromagnetic switch 10 is inserted into this power supply circuit.

冷媒不足検出センサ９の一方の端子は電源に接続され、
他方の端子はアンプ１１及び電磁開閉スイッチ１０の電
磁コイル１２を介して接地されている。冷媒不足検出セ
ンサ９には、光学式センサを用いる。光学式センサは、
発光素子と受光素子とを間隔をおいて突き合わせたもの
である。そして、発光素子が冷媒中に発した光のうち透
過光を受光素子が受けることにより光の通過量を検出す
るようになっている。一方、流通管７内の冷媒は、気液
の混合比に対応する。従って、光学式センサは、冷媒の
気液の混合比の相違による光に透過量の変化を感知し、
冷媒の温度を利用することによりこの混合比に応じて電
気出力を発することができる。One terminal of the refrigerant shortage detection sensor 9 is connected to a power source,
The other terminal is grounded via the amplifier 11 and the electromagnetic coil 12 of the electromagnetic switch 10. An optical sensor is used as the refrigerant shortage detection sensor 9. The optical sensor is
A light-emitting element and a light-receiving element are butted against each other with a space between them. The light receiving element receives transmitted light of the light emitted by the light emitting element into the refrigerant, thereby detecting the amount of light passing through the refrigerant. On the other hand, the refrigerant in the flow pipe 7 corresponds to the gas-liquid mixture ratio. Therefore, the optical sensor detects the change in the amount of light transmitted due to the difference in the gas-liquid mixing ratio of the refrigerant.
By utilizing the temperature of the refrigerant, it is possible to generate electrical output according to this mixing ratio.

上記実施例の冷媒不足検出装置においては、冷媒不足検
出センサ９か流通管７内の冷媒の気液の混合比を光の透
過量に基づいて検知する。もし、冷媒が不足すると気液
の混合比が増すので、これを冷媒不足検出センサ９か感
知して電気信号を出力する。この電気信号をアンプ１１
で増幅する。In the refrigerant shortage detection device of the above embodiment, the refrigerant shortage detection sensor 9 detects the gas-liquid mixture ratio of the refrigerant in the flow pipe 7 based on the amount of light transmitted. If there is a shortage of refrigerant, the gas-liquid mixture ratio will increase, and the refrigerant shortage detection sensor 9 senses this and outputs an electrical signal. Amplify this electrical signal 11
Amplify with.

この電流の通電により電磁コイル１２が励磁されて自動
開閉スィッチ１０がＯＦＦする。従って、コンプレッサ
２の駆動電源回路が開き、コンプレッサ２が稼働を停止
する。The electromagnetic coil 12 is excited by this current, and the automatic opening/closing switch 10 is turned off. Therefore, the drive power circuit of the compressor 2 is opened, and the compressor 2 stops operating.

また、他の実施例として、上記実施例における光学式セ
ンサに代え、自己発熱タイプのサーミスタを用いてもよ
い。このサーミスタは、発熱抵抗体を主体として構成さ
れる。発熱抵抗体は、周期の温度増加に応じて電気抵抗
が小さくなるようになっている。一方、冷媒の温度は、
熱伝導率０．０６１ｋｃａｌ／”Ｃの液化状態の冷媒と
、同じ＜　０．０６１ｋｃａｌ／℃の気化状態の冷媒と
の混合比に応じて異なる。Further, as another embodiment, a self-heating type thermistor may be used instead of the optical sensor in the above embodiment. This thermistor is mainly composed of a heating resistor. The electrical resistance of the heating resistor decreases as the temperature increases over time. On the other hand, the temperature of the refrigerant is
It varies depending on the mixing ratio of a liquefied refrigerant with a thermal conductivity of 0.061 kcal/"C and a vaporized refrigerant with the same <0.061 kcal/"C.

従って、サーミスタは、発熱抵抗体の電気抵抗を利用す
ることにより冷媒の気液の混合比を感知して電気的出力
を発することかできる。Therefore, the thermistor can sense the gas-liquid mixture ratio of the refrigerant by utilizing the electrical resistance of the heating resistor, and can generate an electrical output.

（発明の効果） 以上のように、本発明は、冷媒か循環する循環回路１に
おける高圧側の冷媒流通管７に、冷媒の気液混合状態を
感知して、電気信号を出力する冷媒不足検出センサ９を
設け、この冷媒不足検出センサ９の信号によりコンプレ
ッサ２の駆動用電源回路を開放するようにして冷却装置
の冷媒不足検出装置を構成したため、循環回路１内の冷
媒が不足したら、これを冷媒不足検出センサ９が感知し
てコンプレッサの稼働を停止させることができるから、
冷媒の不足を知って、速やかに対処することができるし
、コンプレッサを損傷させることもない効果を奏する。(Effects of the Invention) As described above, the present invention detects refrigerant shortage by sensing the gas-liquid mixing state of refrigerant and outputting an electric signal to the refrigerant flow pipe 7 on the high pressure side in the circulation circuit 1 in which refrigerant circulates. The refrigerant shortage detection device for the cooling system is constructed by providing a sensor 9 and opening the power supply circuit for driving the compressor 2 in response to a signal from the refrigerant shortage detection sensor 9. Therefore, when there is a shortage of refrigerant in the circulation circuit 1, it is possible to Since the refrigerant shortage detection sensor 9 can sense this and stop the operation of the compressor,
When the refrigerant shortage is known, it can be dealt with promptly, and the compressor is not damaged.

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

第１図は本発明の冷媒不足検出装置を設けた冷媒循環回
路の回路図、第２図は従来の冷媒不足検出装置を設けた
冷媒循環回路の回路図、第３図は冷媒残量に対する冷媒
圧力の変化を示すグラフである。 １・・循環回路、２・・・コンプレッサ、７・・冷媒流
通管、９・・・冷媒不足検出センサ、〕０・・・電磁開
閉スイッチ、１２・・・電磁コイル。 第１図 第２図 Ｂ　　　　　Ａ 冷媒残量 手続補正書（方式） 平成３年３月１９日Figure 1 is a circuit diagram of a refrigerant circulation circuit equipped with the refrigerant shortage detection device of the present invention, Figure 2 is a circuit diagram of a refrigerant circulation circuit equipped with a conventional refrigerant shortage detection device, and Figure 3 is a diagram of refrigerant relative to the remaining amount of refrigerant. It is a graph showing changes in pressure. 1... Circulation circuit, 2... Compressor, 7... Refrigerant distribution pipe, 9... Refrigerant shortage detection sensor, 0... Electromagnetic opening/closing switch, 12... Electromagnetic coil. Figure 1 Figure 2 B A Remaining refrigerant procedure amendment form (method) March 19, 1991

Claims (3)

【特許請求の範囲】[Claims] （１）冷却装置の冷媒循環回路における高圧側の冷媒流
通管に、冷媒の気液混合状態を感知して、コンプレッサ
駆動用の電源回路を開くための電気信号を出力する冷媒
不足検出センサを設けたことを特徴とする冷却装置の冷
媒不足検出装置。(1) A refrigerant shortage detection sensor is installed in the refrigerant flow pipe on the high-pressure side of the refrigerant circulation circuit of the cooling device, which detects the gas-liquid mixing state of the refrigerant and outputs an electric signal to open the power supply circuit for driving the compressor. A refrigerant shortage detection device for a cooling device, characterized in that: （２）前記冷媒不足検出センサが、冷媒の気液混合状態
を光の透過量で検出する光学式センサであることを特徴
とする請求項（１）に記載の冷却装置の冷媒不足検出装
置。(2) The refrigerant shortage detection device for a cooling device according to claim 1, wherein the refrigerant shortage detection sensor is an optical sensor that detects the gas-liquid mixing state of the refrigerant based on the amount of light transmitted. （３）前記冷媒不足検出センサが、冷媒の温度を感知す
る自己発熱タイプのサーミスタであることを特徴とする
請求項（１）に記載の冷却装置の冷媒不足検出装置。(3) The refrigerant shortage detection device for a cooling device according to claim 1, wherein the refrigerant shortage detection sensor is a self-heating type thermistor that senses the temperature of the refrigerant.
JP33706490A 1990-11-30 1990-11-30 Refrigerant shortage detector for cooling device Pending JPH04203866A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP33706490A JPH04203866A (en) 1990-11-30 1990-11-30 Refrigerant shortage detector for cooling device
EP19910311098 EP0488775A3 (en) 1990-11-30 1991-11-29 Detecting system for detecting an insufficient amount of refrigerant in a cooling apparatus and compressor control system incorporating same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP33706490A JPH04203866A (en) 1990-11-30 1990-11-30 Refrigerant shortage detector for cooling device

Publications (1)

Publication Number Publication Date
JPH04203866A true JPH04203866A (en) 1992-07-24

Family

ID=18305091

Family Applications (1)

Application Number Title Priority Date Filing Date
JP33706490A Pending JPH04203866A (en) 1990-11-30 1990-11-30 Refrigerant shortage detector for cooling device

Country Status (2)

Country Link
EP (1) EP0488775A3 (en)
JP (1) JPH04203866A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109073260A (en) * 2016-05-17 2018-12-21 三菱电机株式会社 Air conditioner
CN112513544A (en) * 2018-06-22 2021-03-16 艾默生零售解决方案公司 System and method for optical detection of refrigeration system anomalies

Families Citing this family (5)

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Publication number Priority date Publication date Assignee Title
US5230223A (en) * 1992-03-20 1993-07-27 Envirosystems Corporation Method and apparatus for efficiently controlling refrigeration and air conditioning systems
US7905099B2 (en) * 2008-05-21 2011-03-15 Justak John F Predictive maintenance method and apparatus for HVACR systems
ES2669728T3 (en) * 2016-01-29 2018-05-29 Daikin Industries, Limited Air conditioning system
EP3199892A1 (en) * 2016-01-29 2017-08-02 Daikin Industries, Limited Air conditioning system
EP3199888A1 (en) * 2016-01-29 2017-08-02 Daikin Industries, Limited Air conditioning system

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109073260A (en) * 2016-05-17 2018-12-21 三菱电机株式会社 Air conditioner
CN112513544A (en) * 2018-06-22 2021-03-16 艾默生零售解决方案公司 System and method for optical detection of refrigeration system anomalies

Also Published As

Publication number Publication date
EP0488775A3 (en) 1992-09-23
EP0488775A2 (en) 1992-06-03

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