JP5999499B2

JP5999499B2 - Refrigeration equipment

Info

Publication number: JP5999499B2
Application number: JP2012247565A
Authority: JP
Inventors: 三原　一彦; 一彦三原; 光洋加藤; 裕志八藤後; 豊明木屋; 裕輔倉田
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2012-11-09
Filing date: 2012-11-09
Publication date: 2016-09-28
Anticipated expiration: 2032-11-09
Also published as: JP2014095514A

Description

本発明は、圧縮機と、凝縮器と、絞り手段と、蒸発器とから冷媒回路が構成された冷凍装置に関するものである。 The present invention relates to a refrigeration apparatus in which a refrigerant circuit is constituted by a compressor, a condenser, a throttle means, and an evaporator.

従来よりスーパーマーケットやコンビニエンスストア等の店舗には商品を陳列販売するショーケース（冷却機器）が店舗の売り場内（室内）に複数台設置されている。そして、各ショーケースには、蒸発器をそれぞれ設け、室外に設置された冷凍機とを配管接続している（例えば、特許文献１参照）。これにより、冷凍機に設けられた圧縮機、凝縮器、レシーバタンクと、各ショーケース側に設けられた絞り手段及び蒸発器などが配管により順次環状に接続されて、冷媒回路が構成される。この冷媒回路内には所定量の冷媒が封入されている。 Conventionally, in a store such as a supermarket or a convenience store, a plurality of showcases (cooling devices) for displaying and selling products have been installed in the store floor (indoor). Each showcase is provided with an evaporator and connected to a refrigerator installed outdoors (see, for example, Patent Document 1). As a result, the compressor, the condenser, the receiver tank provided in the refrigerator, the throttling means, the evaporator, and the like provided on each showcase side are sequentially connected in an annular manner by the piping, thereby forming a refrigerant circuit. A predetermined amount of refrigerant is sealed in the refrigerant circuit.

圧縮機が運転されると、冷媒は圧縮されて高温高圧のガス状態となり、凝縮器に流入する。この凝縮器において冷媒は放熱し、凝縮液化した後、一旦レシーバタンクに貯留され、次に絞り手段にて減圧された後、蒸発器に供給される。この蒸発器内において、冷媒は蒸発し、そのときに周囲から吸熱することにより冷却作用を発揮する。 When the compressor is operated, the refrigerant is compressed into a high-temperature and high-pressure gas state and flows into the condenser. In this condenser, the refrigerant dissipates heat and is condensed and liquefied, and then temporarily stored in the receiver tank, and then decompressed by the throttling means, and then supplied to the evaporator. In this evaporator, the refrigerant evaporates, and at that time, the refrigerant absorbs heat from the surroundings and exhibits a cooling action.

特開２０１２−１１７７３３号公報JP 2012-117733 A

上述の如く室外（売場以外の室内、若しくは屋外）に設置された冷凍機と店内のショーケースとが現場にて冷媒配管により接続されるものであるので、溶接箇所やネジ止め部、継手等において冷媒漏洩が発生する危険性が高い。冷媒漏洩が発生すると当然に冷凍装置の冷却能力が低下し、陳列室内に陳列した商品の劣化を招くと共に、大量に漏洩が発生すると地球環境にも多大な悪影響を及ぼすことになる。特に、冷媒としてＨＦＣを採用した場合、レシーバタンクを設けて比較的多量の冷媒を封入するため、冷媒漏洩を発見し難いという問題がある。 As described above, since the refrigerator installed outside the room (inside or outside the sales floor or outdoors) and the showcase in the store are connected by refrigerant piping at the site, in welding locations, screwing parts, joints, etc. There is a high risk of refrigerant leakage. Naturally, when the refrigerant leaks, the cooling capacity of the refrigeration apparatus decreases, which causes deterioration of the products displayed in the display room, and when a large amount of leak occurs, the global environment is greatly affected. In particular, when HFC is employed as the refrigerant, there is a problem that it is difficult to find a refrigerant leak because a receiver tank is provided to enclose a relatively large amount of refrigerant.

そこで、従来では陳列室内の冷えが極端に悪くなったと使用者が判断した場合、リークディテクターやガス漏れ検知スプレー等を用いて各箇所を個々に確認し、冷媒漏洩が原因か否かを推定していたが、係る検出方法では多大な労力と時間を要し、その間にも商品の劣化が進むと共に、顧客にも迷惑となる問題があった。 Therefore, in the past, when the user determined that the cooling in the display room had become extremely bad, each part was individually checked using a leak detector, gas leak detection spray, etc. to estimate whether or not the refrigerant leak was the cause. However, such a detection method requires a great deal of labor and time, and during that time, the product deteriorates and the customer is troubled.

そこで、前記特許文献１では制御装置によってレシーバタンク内に冷媒を回収するポンプダウン運転を実行した後、冷媒回路を複数の領域に分割し、冷媒漏洩の検出に必要な領域の圧力及び温度から当該領域内の冷媒密度を算出し、冷媒密度に当該領域の容積を乗算することで冷媒量を算出し、算出された冷媒量に基づいて冷媒回路からの冷媒漏洩を判定することにより、当該算出された冷媒量と、それ以前に算出された冷媒量、若しくは、基準値等とを比較することにより、冷媒回路からの冷媒漏洩を検出するようにしていた。 Therefore, in Patent Document 1, after performing a pump-down operation in which the refrigerant is collected in the receiver tank by the control device, the refrigerant circuit is divided into a plurality of regions, and the pressure and temperature in the region necessary for detecting refrigerant leakage are used. The refrigerant density in the region is calculated, the refrigerant amount is calculated by multiplying the refrigerant density by the volume of the region, and the refrigerant leakage from the refrigerant circuit is determined based on the calculated refrigerant amount. The refrigerant leakage is detected from the refrigerant circuit by comparing the refrigerant amount with the refrigerant amount calculated before that or the reference value.

しかしながら、レシーバタンクに回収されずに凝縮器に残る冷媒量が、環境条件によって変化するため、係る算出計算によっても冷媒量を正確に算出することが難しかった。そのために、係る算出計算によらずに冷媒漏洩検出のみのための格別な装置を冷凍装置に追加すると、今度はコストの高騰が発生し、使用者の負担となる。 However, since the amount of refrigerant remaining in the condenser without being collected in the receiver tank varies depending on environmental conditions, it is difficult to accurately calculate the amount of refrigerant even by such calculation calculation. For this reason, if a special device for detecting only refrigerant leakage is added to the refrigeration device without relying on such calculation, a cost increase will occur and this will be a burden on the user.

本発明は、係る従来の技術的課題を解決するために成されたものであり、冷媒回路内の冷媒量を精度良く測定し、正確な冷媒漏洩検出を行うことができる冷凍装置を、可能な限り安価に提供することを目的とする。 The present invention has been made in order to solve the conventional technical problem, and a refrigeration apparatus capable of accurately measuring the amount of refrigerant in the refrigerant circuit and performing accurate refrigerant leakage detection is possible. The purpose is to provide it as cheaply as possible.

上記課題を解決するために、本発明の冷凍装置は、圧縮機と、凝縮器と、絞り手段と、蒸発器とから冷媒回路が構成されたものであって、判定用圧縮機と、判定用凝縮器と、判定用絞り手段と、判定用蒸発器とから判定用冷媒回路が構成された冷媒量判定装置と、制御手段とを備え、冷媒量判定装置は、凝縮器を出た冷媒と判定用蒸発器とを熱交換させるカスケード熱交換器と、このカスケード熱交換器の下流側であって絞り手段の上流側に接続されたレシーバタンクと、このレシーバタンクの冷媒出口に接続されたポンプダウン用弁装置と、レシーバタンク内の冷媒量を検出する冷媒量検出手段とを有し、制御手段は、冷媒量判定モードを有し、この冷媒量判定モードにおいてはポンプダウン用弁装置を閉じた状態で圧縮機及び判定用圧縮機を運転し、レシーバタンク内に冷媒を回収するポンプダウン運転を実行すると共に、冷媒量検出手段の出力に基づいてレシーバタンク内の冷媒量を測定し、冷媒回路からの冷媒漏洩を判定することを特徴とする。 In order to solve the above-described problems, a refrigeration apparatus according to the present invention includes a compressor, a condenser, a throttle means, and an evaporator, and includes a refrigerant circuit, a determination compressor, and a determination A refrigerant amount determination device having a determination refrigerant circuit composed of a condenser, a determination throttling unit, and a determination evaporator; and a control unit. The refrigerant amount determination device determines that the refrigerant has left the condenser. Cascade heat exchanger for exchanging heat with the evaporator, a receiver tank connected downstream of the cascade heat exchanger and upstream of the throttle means, and a pump down connected to the refrigerant outlet of the receiver tank The control device has a refrigerant amount determination mode, and in this refrigerant amount determination mode, the pump-down valve device is closed. Compressor and judgment compression in state And performing a pump-down operation for collecting the refrigerant in the receiver tank, measuring the refrigerant amount in the receiver tank based on the output of the refrigerant amount detection means, and determining refrigerant leakage from the refrigerant circuit. Features.

請求項２の発明の冷凍装置は、上記発明においてレシーバタンクは、縦長形状を呈することを特徴とする。 According to a second aspect of the present invention, in the above invention, the receiver tank has a vertically long shape.

請求項３の発明の冷凍装置は、上記各発明において制御手段は、冷媒量判定モードを実行する際に蒸発器の霜取を行うことを特徴とする。 The refrigeration apparatus according to a third aspect of the present invention is characterized in that, in each of the above inventions, the control means defrosts the evaporator when executing the refrigerant amount determination mode.

請求項４の発明の冷凍装置は、上記各発明において制御手段は、冷媒量判定モードにおいて冷媒漏洩と判定した場合には、所定の警報を発することを特徴とする。 The refrigeration apparatus according to a fourth aspect of the invention is characterized in that, in each of the above inventions, the control means issues a predetermined alarm when it is determined that the refrigerant leaks in the refrigerant amount determination mode.

請求項５の発明の冷凍装置は、上記各発明において給湯器を備え、判定用凝縮器からの放熱を利用して給湯器における湯の生成を行うことを特徴とする。 A refrigeration apparatus according to a fifth aspect of the present invention is characterized in that in each of the above-mentioned inventions, a hot water heater is provided, and hot water is generated in the hot water heater using heat radiation from the determination condenser.

請求項６の発明の冷凍装置は、上記各発明において冷媒量判定装置は、レシーバタンクの入口側及び出口側に、入口側弁装置及び出口側弁装置を有することを特徴とする。 A refrigeration apparatus according to a sixth aspect of the present invention is characterized in that, in each of the above inventions, the refrigerant amount determination device has an inlet side valve device and an outlet side valve device on an inlet side and an outlet side of the receiver tank.

本発明によれば、圧縮機と、凝縮器と、絞り手段と、蒸発器とから冷媒回路が構成された冷凍装置において、判定用圧縮機と、判定用凝縮器と、判定用絞り手段と、判定用蒸発器とから判定用冷媒回路が構成された冷媒量判定装置と、制御手段とを備え、冷媒量判定装置は、凝縮器を出た冷媒と判定用蒸発器とを熱交換させるカスケード熱交換器と、このカスケード熱交換器の下流側であって絞り手段の上流側に接続されたレシーバタンクと、このレシーバタンクの冷媒出口に接続されたポンプダウン用弁装置と、レシーバタンク内の冷媒量を検出する冷媒量検出手段とを有し、制御手段は、冷媒量判定モードを有し、この冷媒量判定モードにおいてはポンプダウン用弁装置を閉じた状態で圧縮機及び判定用圧縮機を運転し、レシーバタンク内に冷媒を回収するポンプダウン運転を実行するようにしたので、ポンプダウン運転時にレシーバタンク内に回収される冷媒は、凝縮器を出てカスケード熱交換器を通過する過程で冷媒量判定装置の蒸発器により冷却されることになる。 According to the present invention, in the refrigeration apparatus in which the refrigerant circuit is configured by the compressor, the condenser, the throttle means, and the evaporator, the determination compressor, the determination condenser, and the determination throttle means, A refrigerant amount determination device in which a determination refrigerant circuit is configured from the determination evaporator, and a control unit, and the refrigerant amount determination device performs cascade heat to exchange heat between the refrigerant discharged from the condenser and the determination evaporator. An exchanger, a receiver tank connected to the downstream side of the cascade heat exchanger and upstream of the throttle means, a pump-down valve device connected to the refrigerant outlet of the receiver tank, and a refrigerant in the receiver tank Refrigerant amount detection means for detecting the amount, and the control means has a refrigerant amount determination mode, and in this refrigerant amount determination mode, the compressor and the determination compressor are operated with the pump-down valve device closed. Driving and receiver tank Since the pump-down operation for recovering the refrigerant is performed, the refrigerant collected in the receiver tank during the pump-down operation is evaporated by the refrigerant quantity determination device in the process of leaving the condenser and passing through the cascade heat exchanger. It will be cooled by the vessel.

従って、レシーバタンク内に回収された冷媒の圧力及び温度を規定の状態とすることができるようになる。また、カスケード熱交換器において冷却されることにより、それより上流側の冷媒回路内の冷媒を残らずレシーバタンク内に引き込むことが可能となる。これらにより、レシーバタンク内の冷媒量を冷媒量検出手段にて検出することで、環境条件に左右されずに制御手段は、冷媒量検出手段の出力に基づいて極めて精度良くレシーバタンクの冷媒量を測定できるようになり、冷媒回路からの冷媒漏洩を正確に判定することができるようになる。 Accordingly, the pressure and temperature of the refrigerant collected in the receiver tank can be set to a specified state. Further, by cooling in the cascade heat exchanger, it is possible to draw all the refrigerant in the refrigerant circuit upstream from the refrigerant tank into the receiver tank. As a result, the refrigerant amount in the receiver tank is detected by the refrigerant amount detection means, so that the control means can accurately determine the refrigerant amount in the receiver tank based on the output of the refrigerant amount detection means regardless of the environmental conditions. It becomes possible to measure the refrigerant leakage accurately from the refrigerant circuit.

この場合、請求項２の発明の如くレシーバタンクを縦長形状とすることで、冷媒量検出手段がレシーバタンク内の液面の位置で冷媒量を検出する場合に、その分解能を向上させてより正確に冷媒量の測定を行うことが可能となる。 In this case, by making the receiver tank vertically long as in the invention of claim 2, when the refrigerant quantity detecting means detects the refrigerant quantity at the position of the liquid level in the receiver tank, the resolution is improved and more accurate. It becomes possible to measure the amount of refrigerant.

また、請求項３の発明の如く制御手段が、冷媒量判定モードを実行する際に蒸発器の霜取を行うようにすれば、ポンプダウン運転で蒸発器内の冷媒がレシーバタンクに回収され、蒸発器の温度が上昇する冷媒量判定モードに合わせて蒸発器の霜取を行うことで、効率の良い霜取と冷媒漏洩判定を行うことができるようになる。 Further, if the control means performs defrosting of the evaporator when executing the refrigerant amount determination mode as in the invention of claim 3, the refrigerant in the evaporator is recovered in the receiver tank by the pump-down operation, By performing defrosting of the evaporator in accordance with the refrigerant amount determination mode in which the temperature of the evaporator rises, efficient defrosting and refrigerant leakage determination can be performed.

また、請求項４の発明の如く制御手段が、冷媒漏洩と判定した場合には、所定の警報を発するようにすることにより、冷媒漏洩の発生を迅速に使用者に報知し、冷媒漏洩量を最低限に抑えて冷凍能力の悪影響を最小限に抑制することができるようになる。 Further, when the control means determines that the refrigerant is leaking as in the invention of claim 4, it is possible to promptly notify the user of the occurrence of the refrigerant leakage by issuing a predetermined alarm, and to determine the refrigerant leakage amount. It becomes possible to minimize the adverse effect of the refrigerating capacity by minimizing.

更に、請求項５の発明の如く給湯器を設け、判定用凝縮器からの放熱を利用して給湯器における湯の生成を行うようにすることにより、判定用冷媒回路からの廃熱を利用して給湯を行うことが可能となり、給湯機能の追加と冷凍機の過冷却の増大による高効率化により、投資（冷媒量判定装置への投資）の回収を行うことができるようになる。 Furthermore, a hot water heater is provided as in the invention of claim 5, and the heat generated from the determination refrigerant circuit is utilized by generating the hot water in the water heater by utilizing the heat radiation from the determination condenser. Thus, it becomes possible to recover the investment (investment in the refrigerant quantity determination device) by adding a hot water supply function and increasing efficiency by increasing the supercooling of the refrigerator.

そして、請求項６の発明の如く冷媒量判定装置がレシーバタンクの入口側及び出口側に入口側弁装置及び出口側弁装置を有するようにすれば、ポンプダウン運転を実行して冷媒量判定装置のレシーバタンクに冷媒を回収した後、入口側弁装置と出口側弁装置を閉じることで、既存の冷媒回路のレシーバタンクに代えて冷媒量判定装置のレシーバタンクを取り付けた際に、既存のレシーバタンクを取り外す作業を容易に行えるようになる。 Then, if the refrigerant quantity determination device has the inlet side valve device and the outlet side valve device on the inlet side and the outlet side of the receiver tank as in the invention of claim 6, the pump down operation is performed and the refrigerant amount determination device is executed. After collecting the refrigerant in the receiver tank, the inlet side valve device and the outlet side valve device are closed, so that when the receiver tank of the refrigerant quantity determination device is installed instead of the receiver tank of the existing refrigerant circuit, the existing receiver The tank can be easily removed.

本発明を適用した冷凍装置の冷媒回路図である。It is a refrigerant circuit figure of the refrigerating device to which the present invention is applied.

以下、本発明の実施形態について図面を参照して説明する。
図１は本発明の実施形態にかかる冷凍装置Ｒの冷媒回路図である。本実施例における冷凍装置Ｒは、例えばスーパーマーケット等の店舗に複数台設置されたショーケース５陳列室内を冷却するものであり、圧縮機６、凝縮器７及び凝縮器用送風機８等が設置された冷凍機３と、一台若しくは複数台のショーケース５にそれぞれ設置された蒸発器９や膨張弁（絞り手段）１１、ポンプダウン用弁装置としての電磁弁５０等を据え付け現場にて冷媒配管１２、１３により接続することで冷媒回路１が構成される。この冷媒回路１内には、冷媒の一例としてＲ４０４Ａ（ＨＦＣ冷媒）が所定量充填されている。 Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a refrigerant circuit diagram of a refrigeration apparatus R according to an embodiment of the present invention. The refrigeration apparatus R in this embodiment cools the display case 5 display room installed in a store such as a supermarket, for example, and is equipped with a compressor 6, a condenser 7, a condenser blower 8, and the like. The refrigerant pipe 12 at the installation site of the machine 3, the evaporator 9 and the expansion valve (throttle means) 11 installed in one or a plurality of showcases 5, the electromagnetic valve 50 as a pump-down valve device, etc. The refrigerant circuit 1 is configured by connecting them by 13. The refrigerant circuit 1 is filled with a predetermined amount of R404A (HFC refrigerant) as an example of the refrigerant.

冷凍機３は店舗の売り場以外の屋内、若しくは、屋外（室外）に設置され、ショーケース５は店舗の売り場内（室内）に設置される。冷凍機３の圧縮機６は、運転周波数を変更することで回転数を制御可能とされており、吸込口２１には冷媒導入管２２が接続され、この冷媒導入管２２が冷媒配管１３に接続される。また、吐出口２３には冷媒吐出管２４が接続され、凝縮器７、本発明の冷媒量判定装置２６を介して冷媒配管１２に接続される。 The refrigerator 3 is installed indoors or outdoors (outdoors) other than the store floor, and the showcase 5 is installed in the store floor (indoors). The compressor 6 of the refrigerator 3 is capable of controlling the rotation speed by changing the operating frequency. A refrigerant introduction pipe 22 is connected to the suction port 21, and the refrigerant introduction pipe 22 is connected to the refrigerant pipe 13. Is done. In addition, a refrigerant discharge pipe 24 is connected to the discharge port 23 and is connected to the refrigerant pipe 12 via the condenser 7 and the refrigerant amount determination device 26 of the present invention.

ショーケース５は店舗内等に設置され、冷媒配管１２及び１３に接続されている。ショーケース５は、冷媒配管１２と連結するケース側冷媒配管１８及び冷媒配管１３と連結するケース側冷媒配管１９とを有している。ケース側冷媒配管１８には、電磁弁５０と絞り手段としての膨張弁１１が順次介設されると共に、蒸発器９の冷媒入口側に接続される。蒸発器９の冷媒出口側には、ケース側冷媒配管１９を介して冷媒配管１３に接続される。蒸発器９には、当該蒸発器に送風する図示しない冷気循環用送風機が隣接されている。 The showcase 5 is installed in a store or the like and connected to the refrigerant pipes 12 and 13. The showcase 5 includes a case side refrigerant pipe 18 connected to the refrigerant pipe 12 and a case side refrigerant pipe 19 connected to the refrigerant pipe 13. The case-side refrigerant pipe 18 is provided with an electromagnetic valve 50 and an expansion valve 11 as a throttle means in order, and is connected to the refrigerant inlet side of the evaporator 9. The refrigerant outlet side of the evaporator 9 is connected to the refrigerant pipe 13 via a case side refrigerant pipe 19. The evaporator 9 is adjacent to a blower for circulating cold air (not shown) that blows air to the evaporator.

そして、上述したように冷媒配管１３は冷媒導入管２２を介して圧縮機６に接続され、冷媒配管１２は電磁弁５０に接続されることにより、本実施例における冷凍装置Ｒの冷媒回路１が構成される。尚、２７は冷媒導入管２２に接続されて冷媒回路１の低圧側圧力を検出する圧力センサ、２８は冷媒吐出管２４に接続されて冷媒回路１の高圧側圧力を検出する圧力センサである。また、３１は冷媒導入管２２の温度を検出する温度センサ、３２は冷媒吐出管２４の温度を検出する温度センサである。 As described above, the refrigerant pipe 13 is connected to the compressor 6 via the refrigerant introduction pipe 22, and the refrigerant pipe 12 is connected to the electromagnetic valve 50, whereby the refrigerant circuit 1 of the refrigeration apparatus R in the present embodiment is Composed. A pressure sensor 27 is connected to the refrigerant introduction pipe 22 to detect the low-pressure side pressure of the refrigerant circuit 1, and 28 is a pressure sensor connected to the refrigerant discharge pipe 24 to detect the high-pressure side pressure of the refrigerant circuit 1. Further, 31 is a temperature sensor that detects the temperature of the refrigerant introduction pipe 22, and 32 is a temperature sensor that detects the temperature of the refrigerant discharge pipe 24.

次に、本発明の冷媒量判定装置２６について説明する。冷媒量判定装置２６は既存の冷凍機３にオプション的に追加して取り付けるか、或いは、冷凍機３の製造時に内蔵取付されるものであり、判定用圧縮機としての圧縮機３６と、判定用凝縮器としての凝縮器３７と、判定用絞り手段としての膨張弁３８と、判定用蒸発器としての蒸発器３９とを備え、これらが環状に配管接続されて判定用の冷媒回路４１を構成している。 Next, the refrigerant | coolant amount determination apparatus 26 of this invention is demonstrated. The refrigerant quantity determination device 26 is optionally added to the existing refrigerator 3 or is installed in the refrigerator 3 when it is manufactured, and includes a compressor 36 as a determination compressor, and a determination A condenser 37 as a condenser, an expansion valve 38 as a judgment throttle means, and an evaporator 39 as a judgment evaporator are provided, and these are connected in a ring to form a judgment refrigerant circuit 41. ing.

冷媒量判定装置２６は更に、縦長で所定容量を有するレシーバタンク４２と、このレシーバタンク４２の上部（入口側）に連通接続された入口側配管４３と、レシーバタンク４２の下部（出口側）に連通接続された出口側配管４４と、各配管中に介設された入口側弁装置及び出口側弁装置としての入口側手動弁４６及び出口側手動弁４７と、レシーバタンク４２内の冷媒量をその液面の高さで検出する冷媒量検出手段としての液面センサ４８と、入口側配管４３を流れる冷媒と蒸発器３９とを熱交換させるカスケード熱交換器４９を備えている。この冷媒量判定装置２６が冷媒回路１に接続されることで、電磁弁５０はレシーバタンク４２の出口側に位置することになる。 The refrigerant quantity determination device 26 further includes a receiver tank 42 that is vertically long and has a predetermined capacity, an inlet-side pipe 43 that is connected to the upper part (inlet side) of the receiver tank 42, and a lower part (outlet side) of the receiver tank 42. The outlet side pipe 44 connected in communication, the inlet side valve device and the outlet side manual valve 47 as the inlet side valve device and the outlet side valve device interposed in each pipe, and the amount of refrigerant in the receiver tank 42 A liquid level sensor 48 serving as a refrigerant amount detecting means for detecting the level of the liquid level, and a cascade heat exchanger 49 for exchanging heat between the refrigerant flowing through the inlet side pipe 43 and the evaporator 39 are provided. By connecting the refrigerant amount determination device 26 to the refrigerant circuit 1, the electromagnetic valve 50 is positioned on the outlet side of the receiver tank 42.

また、実施例の冷媒量判定装置２６には更に、水配管５１と、この水配管５１中に介設されたポンプ５２と、このポンプ５２下流側の水配管５１中を流れる水と凝縮器３７とを熱交換させる水熱交換器５３が設けられている。そして、入口側配管４３は冷凍機３の凝縮器７の出口配管５４に接続され、出口側配管４４は冷媒配管１２に接続される。これにより、レシーバタンク４２はカスケード熱交換器４９の冷媒下流側であって、膨張弁１１の上流側に位置することになる。更に、ポンプ５２上流側の水配管５１は水道配管に接続されると共に、水熱交換器５３の下流側の水配管５１は給湯器５６（実際には給湯器５６の貯湯タンク）に接続される。 Further, the refrigerant amount determination device 26 of the embodiment further includes a water pipe 51, a pump 52 interposed in the water pipe 51, water flowing in the water pipe 51 downstream of the pump 52, and the condenser 37. And a water heat exchanger 53 for exchanging heat with each other. The inlet side pipe 43 is connected to the outlet pipe 54 of the condenser 7 of the refrigerator 3, and the outlet side pipe 44 is connected to the refrigerant pipe 12. As a result, the receiver tank 42 is positioned downstream of the refrigerant in the cascade heat exchanger 49 and upstream of the expansion valve 11. Further, the water pipe 51 on the upstream side of the pump 52 is connected to a water pipe, and the water pipe 51 on the downstream side of the water heat exchanger 53 is connected to a water heater 56 (actually a hot water storage tank of the water heater 56). .

また、カスケード熱交換器４９の下流側の入口側配管４３には、凝縮器７を出てカスケード熱交換器４９を経た冷媒の温度を検出する温度センサ５７が取り付けられており、この温度センサ５７を含む各温度センサ３１、３２、圧力センサ２７、２８、液面センサ４８は、汎用マイクロコンピュータから構成された制御手段を構成する制御装置Ｃの入力に接続されている。更に、この制御装置Ｃの出力には前記圧縮機６や凝縮器用送風機８、膨張弁１１、３８、電磁弁５０、ポンプ５２が接続される。 In addition, a temperature sensor 57 that detects the temperature of the refrigerant that has exited the condenser 7 and passed through the cascade heat exchanger 49 is attached to the inlet-side piping 43 on the downstream side of the cascade heat exchanger 49. The temperature sensors 31 and 32, the pressure sensors 27 and 28, and the liquid level sensor 48 are connected to the input of a control device C that constitutes a control means constituted by a general-purpose microcomputer. Further, the compressor 6, the condenser blower 8, the expansion valves 11 and 38, the electromagnetic valve 50, and the pump 52 are connected to the output of the control device C.

尚、実際には冷凍機３やショーケース５、冷媒量判定装置２６のそれぞれに制御手段が設けられ、それらが連携して動作するものであるが、ここでは各制御手段（冷凍機３の制御手段、ショーケース５の制御手段、及び、冷媒量判定装置２６の制御手段）を含めて制御装置Ｃとする。また、この制御装置Ｃの出力には更にブザーやランプ等からなる警報器５８が接続されている。 Actually, the refrigerator 3, the showcase 5, and the refrigerant quantity determination device 26 are each provided with control means and operate in cooperation with each other, but here, each control means (control of the refrigerator 3 is controlled). The control device C including the control means of the showcase 5 and the control means of the refrigerant amount determination device 26). Further, an alarm device 58 comprising a buzzer, a lamp and the like is further connected to the output of the control device C.

以上の構成で次に本発明の冷凍装置Ｒの動作を説明する。
（１）通常運転モード
ショーケース５の陳列室内を冷却するため、制御装置Ｃは通常運転モードを実行する。この通常運転モードで制御装置Ｃは圧縮機６、凝縮器用送風機８を運転し、電磁弁５０を開放する。尚、手動弁４６及び４７は通常は開けておく。尚、冷媒量判定装置２６の圧縮機３６は停止している。圧縮機６が運転されると冷媒導入管２２を介して吸込口２１から吸い込まれた低圧の冷媒ガスが圧縮され、高温高圧のガス冷媒となって吐出口２３から冷媒吐出管２４に吐出される。 Next, the operation of the refrigeration apparatus R of the present invention with the above configuration will be described.
(1) Normal operation mode In order to cool the display room of the showcase 5, the control device C executes the normal operation mode. In this normal operation mode, the control device C operates the compressor 6 and the condenser fan 8 and opens the electromagnetic valve 50. The manual valves 46 and 47 are normally opened. In addition, the compressor 36 of the refrigerant | coolant amount determination apparatus 26 has stopped. When the compressor 6 is operated, the low-pressure refrigerant gas sucked from the suction port 21 through the refrigerant introduction pipe 22 is compressed and becomes a high-temperature and high-pressure gas refrigerant and is discharged from the discharge port 23 to the refrigerant discharge pipe 24. .

冷媒吐出管２４に吐出された冷媒ガスは凝縮器７に流入し、そこで凝縮器用送風機８により空冷され、凝縮液化する。この液化冷媒は出口配管５４を経て冷媒量判定装置２６の入口側配管４３に流入し、カスケード熱交換器４９、手動弁４６を順次経てレシーバタンク４２内に流入する。そこで液冷媒は一旦貯留された後、レシーバタンク４２から出て手動弁４７を通過し、出口側配管４４から冷媒配管１２に流入する。 The refrigerant gas discharged to the refrigerant discharge pipe 24 flows into the condenser 7, where it is air-cooled by the condenser blower 8 to be condensed and liquefied. The liquefied refrigerant flows into the inlet side pipe 43 of the refrigerant quantity determination device 26 through the outlet pipe 54, and then flows into the receiver tank 42 through the cascade heat exchanger 49 and the manual valve 46 in order. Therefore, the liquid refrigerant is temporarily stored, then comes out of the receiver tank 42, passes through the manual valve 47, and flows into the refrigerant pipe 12 from the outlet side pipe 44.

冷媒配管１２に流入した液冷媒はショーケース５内に入り、電磁弁５０を経て膨張弁１１に絞られた後、蒸発器９に流入して蒸発する。このときの吸熱作用で冷気循環用送風機により通風される空気を冷却し、この冷気を陳列室内に循環して所定温度（冷凍、冷蔵）に冷却する。蒸発器９から出た低音のガス冷媒は冷媒配管１３を経て冷凍機３に戻り、冷媒導入管２２から圧縮機６の吸込口２１に戻る循環を繰り返す。 The liquid refrigerant that has flowed into the refrigerant pipe 12 enters the showcase 5, is throttled by the expansion valve 11 through the electromagnetic valve 50, and then flows into the evaporator 9 and evaporates. The air ventilated by the cool air circulation blower is cooled by the endothermic action at this time, and the cool air is circulated in the display room to cool to a predetermined temperature (freezing, refrigeration). The low-frequency gas refrigerant coming out of the evaporator 9 returns to the refrigerator 3 through the refrigerant pipe 13 and repeats circulation returning from the refrigerant introduction pipe 22 to the suction port 21 of the compressor 6.

制御装置Ｃはショーケース５内の温度を検出する図示しない温度センサの出力に基づいて圧縮機６の回転数を制御し、陳列室内を所定温度に制御する。また、膨張弁１１の弁開度を蒸発器９の入口／出口温度（図示しない温度センサで検出）で制御し、蒸発器９における冷媒の過熱度を適正値に制御する。 The control device C controls the number of rotations of the compressor 6 based on the output of a temperature sensor (not shown) that detects the temperature in the showcase 5 and controls the display chamber to a predetermined temperature. Further, the opening degree of the expansion valve 11 is controlled by the inlet / outlet temperature of the evaporator 9 (detected by a temperature sensor (not shown)), and the superheat degree of the refrigerant in the evaporator 9 is controlled to an appropriate value.

（２）給湯運転モード
また、給湯器５６において湯を生成し、給湯を行いたい場合、使用者の選択操作により制御装置Ｃは給湯運転モードを実行する。この給湯運転モードでは、制御装置Ｃは冷媒量判定装置２６の圧縮機３６を運転すると共に、ポンプ５２を運転する。圧縮機３６が運転されると、冷媒回路４１の低圧側から吸い込まれた冷媒が圧縮され、高温高圧となって凝縮器３７に吐出される。凝縮器３７に流入した高温冷媒はそこで放熱し、凝縮液化する。ポンプ５２により水配管５１に送給される水は、水熱交換器５３を通過する過程で凝縮器３７からの放熱により加熱され（凝縮器３７の放熱を利用）、温水となって給湯器５６に供給される。 (2) Hot-water supply operation mode In addition, when hot water is generated in the water heater 56 and it is desired to perform hot-water supply, the control device C executes the hot-water supply operation mode by a user's selection operation. In this hot water supply operation mode, the control device C operates the compressor 36 of the refrigerant amount determination device 26 and also operates the pump 52. When the compressor 36 is operated, the refrigerant sucked from the low pressure side of the refrigerant circuit 41 is compressed, becomes high temperature and high pressure, and is discharged to the condenser 37. The high-temperature refrigerant that has flowed into the condenser 37 dissipates heat and condenses into liquid. The water supplied to the water pipe 51 by the pump 52 is heated by the heat radiation from the condenser 37 in the process of passing through the water heat exchanger 53 (using the heat radiation of the condenser 37), and becomes hot water as a hot water heater 56. To be supplied.

それにより、給湯器５６の貯湯タンク内に湯が貯留されるので、店舗のバックヤードにおける作業に湯を供することができるようになる。尚、凝縮器３７を出た液冷媒は膨張弁３８で絞られた後、蒸発器３９に入り、そこで蒸発した後、圧縮機３６に吸い込まれる循環を繰り返す。蒸発器３９では冷媒は吸熱作用を発揮するので、冷凍機３の凝縮器７を出て入口側配管４３を流れる冷媒をカスケード熱交換器４９において過冷却することができる。即ち、この状態で冷媒回路１と冷媒回路４１は、冷媒回路１を低段側、冷媒回路４１を高段側とする二元冷凍サイクルを構成することになる。尚、凝縮器３７では冷媒が凝縮しない場合もある。その場合、凝縮器３７はガスクーラ（放熱器）となる。 Thereby, since hot water is stored in the hot water storage tank of the water heater 56, the hot water can be used for work in the backyard of the store. The liquid refrigerant exiting the condenser 37 is throttled by the expansion valve 38 and then enters the evaporator 39 where it evaporates and then repeats the circulation sucked into the compressor 36. Since the refrigerant exhibits an endothermic effect in the evaporator 39, the refrigerant flowing out of the condenser 7 of the refrigerator 3 and flowing through the inlet side pipe 43 can be supercooled in the cascade heat exchanger 49. That is, in this state, the refrigerant circuit 1 and the refrigerant circuit 41 constitute a dual refrigeration cycle in which the refrigerant circuit 1 is at the lower stage side and the refrigerant circuit 41 is at the higher stage side. The condenser 37 may not condense the refrigerant. In that case, the condenser 37 becomes a gas cooler (heat radiator).

（３）過冷却運転モード（給湯運転モード）
ここで、前述した通常運転モードにおいて冷凍装置Ｒが過負荷状態となり、圧力センサ２８が検出する冷媒回路１の高圧側圧力が上昇した場合、制御装置Ｃは過冷却運転モードに移行する。この過冷却運転モードでは制御装置Ｃは上述した給湯運転モードと同様に冷媒量判定装置２６の圧縮機３６を運転する。動作は上記給湯運転モードと同様である。即ち、冷媒量判定装置２６の蒸発器３９における冷媒の吸熱作用により、冷凍機３の凝縮器７を出て入口側配管４３を流れる冷媒がカスケード熱交換器４９において過冷却されるようになるので、冷凍機３の冷媒回路１の高圧側における圧力上昇を抑え、冷凍能力が向上される。尚、この場合もポンプ５２を運転することにより、給湯器５６の貯湯タンクに湯を生成することができる。 (3) Supercooling operation mode (hot water supply operation mode)
Here, when the refrigeration apparatus R is overloaded in the normal operation mode described above and the high-pressure side pressure of the refrigerant circuit 1 detected by the pressure sensor 28 increases, the control apparatus C shifts to the supercooling operation mode. In this supercooling operation mode, the control device C operates the compressor 36 of the refrigerant quantity determination device 26 as in the hot water supply operation mode described above. The operation is the same as in the hot water supply operation mode. That is, due to the endothermic action of the refrigerant in the evaporator 39 of the refrigerant quantity determination device 26, the refrigerant flowing out of the condenser 7 of the refrigerator 3 and flowing through the inlet side pipe 43 is supercooled in the cascade heat exchanger 49. The pressure increase on the high pressure side of the refrigerant circuit 1 of the refrigerator 3 is suppressed, and the refrigerating capacity is improved. In this case as well, hot water can be generated in the hot water storage tank of the water heater 56 by operating the pump 52.

（４）霜取運転モード
次に、上記通常運転モードにおいて制御装置Ｃは所定時間毎（１日に２回〜３回）にショーケース５の蒸発器９の霜取運転モードを実行する。この霜取運転モードでは制御装置Ｃは圧縮機６を停止する（給湯を必要としない場合は圧縮機３６も停止）。これにより、蒸発器９には冷媒が供給されなくなる。また、前述した冷気循環用送風機を運転するので、蒸発器９に付着した霜は通風によって融解される（オフサイクルデフ）。尚、この霜取運転は所定時間経過後、或いは蒸発器９の温度が所定温度に上昇（図示しない蒸発器温度センサで検出）した場合に終了し、通常運転モードに復帰する。 (4) Defrosting operation mode Next, in the normal operation mode, the control device C executes the defrosting operation mode of the evaporator 9 of the showcase 5 every predetermined time (twice to three times a day). In this defrosting operation mode, the control device C stops the compressor 6 (when the hot water supply is not required, the compressor 36 is also stopped). As a result, no refrigerant is supplied to the evaporator 9. Further, since the above-described cool air circulation blower is operated, the frost adhering to the evaporator 9 is melted by ventilation (off-cycle differential). This defrosting operation ends when a predetermined time has elapsed or when the temperature of the evaporator 9 rises to a predetermined temperature (detected by an evaporator temperature sensor not shown) and returns to the normal operation mode.

（５）冷媒量判定モード（霜取運転モード）
次に、制御装置Ｃは一定期間毎に冷媒回路１からの冷媒漏洩を判定するための冷媒量判定モードを実行する。この冷媒量判定モードで制御装置Ｃは、先ず、電磁弁５０を閉じ（手動弁４６及び４７は開放）、圧縮機６を運転することで、電磁弁５０以降の冷媒回路１内の冷媒をレシーバタンク４２に回収するポンプダウン運転を実行する。このポンプダウン運転で冷媒回路１内の冷媒はレシーバタンク４２内に回収され、貯留されていく。 (5) Refrigerant amount determination mode (defrosting operation mode)
Next, the control apparatus C performs the refrigerant | coolant amount determination mode for determining the refrigerant | coolant leakage from the refrigerant circuit 1 for every fixed period. In this refrigerant amount determination mode, the control device C first closes the electromagnetic valve 50 (manual valves 46 and 47 are opened) and operates the compressor 6 to receive the refrigerant in the refrigerant circuit 1 after the electromagnetic valve 50 as a receiver. A pump-down operation for collecting in the tank 42 is executed. With this pump-down operation, the refrigerant in the refrigerant circuit 1 is collected and stored in the receiver tank 42.

また、冷媒量判定装置２６の圧縮機３６を運転し、前述同様に蒸発器３８により、冷凍機３の凝縮器７を出て入口側配管４３を流れる冷媒をカスケード熱交換器４９において冷却する（前述同様に冷媒回路１と冷媒回路４１は、冷媒回路１を低段側、冷媒回路４１を高段側とする二元冷凍サイクルを構成）。その際、制御装置Ｃは温度センサ５７の出力に基づき、カスケード熱交換器４９を経た入口側配管４３を流れる冷媒の温度が規定の温度となるように圧縮機３６の運転を制御する。 Further, the compressor 36 of the refrigerant quantity determination device 26 is operated, and the refrigerant flowing out of the condenser 7 of the refrigerator 3 and flowing through the inlet side pipe 43 is cooled in the cascade heat exchanger 49 by the evaporator 38 as described above ( As described above, the refrigerant circuit 1 and the refrigerant circuit 41 constitute a dual refrigeration cycle in which the refrigerant circuit 1 is on the low stage side and the refrigerant circuit 41 is on the high stage side). At that time, the control device C controls the operation of the compressor 36 based on the output of the temperature sensor 57 so that the temperature of the refrigerant flowing through the inlet side pipe 43 that has passed through the cascade heat exchanger 49 becomes a specified temperature.

これにより、レシーバタンク４２内に流入する液冷媒の圧力及び温度は規定の状態とされ、レシーバタンク４２内の圧力及び温度も既定値に維持されるようになる。特に、カスケード熱交換器４９において冷却されることにより、それより上流側の冷媒回路１内の冷媒は残らずレシーバタンク４２内に引き込まれるようになる。 As a result, the pressure and temperature of the liquid refrigerant flowing into the receiver tank 42 are in a specified state, and the pressure and temperature in the receiver tank 42 are also maintained at predetermined values. In particular, by cooling in the cascade heat exchanger 49, all the refrigerant in the refrigerant circuit 1 on the upstream side is not drawn and is drawn into the receiver tank 42.

そして、ポンプダウン運転を所定時間実行した後（予め冷媒回路１内の全ての冷媒を回収できる時間を計測し、制御装置Ｃに設定しておく）、若しくは、圧力センサ２７が検出する低圧側圧力が所定値（冷媒回路１内の全ての冷媒が回収された状態の低圧側圧力）に低下した場合、制御装置Ｃは液面センサ４８の出力に基づき、レシーバタンク４２内の液冷媒の量をその液面の高さから測定する。 Then, after the pump-down operation has been performed for a predetermined time (measured in advance is a time during which all the refrigerant in the refrigerant circuit 1 can be collected and set in the control device C), or the low-pressure side pressure detected by the pressure sensor 27 Is reduced to a predetermined value (low pressure side pressure in a state where all the refrigerant in the refrigerant circuit 1 has been recovered), the control device C determines the amount of liquid refrigerant in the receiver tank 42 based on the output of the liquid level sensor 48. Measure from the height of the liquid level.

そして、制御装置Ｃは測定した冷媒量を所定の基準値と比較し、基準値と同等であった場合（所定の余裕度を加味して）、冷媒回路１からの冷媒漏洩は無いものと判定し、冷媒量判定モードを終了して通常運転モードに復帰する。 And the control apparatus C compares the measured refrigerant | coolant amount with a predetermined reference value, and when it is equal to a reference value (a predetermined margin is considered), it determines with there being no refrigerant leak from the refrigerant circuit 1. Then, the refrigerant quantity determination mode is terminated and the normal operation mode is restored.

尚、この冷媒量判定モードでは蒸発器９内の冷媒も吸引されて無くなるので、蒸発器９は実質的に霜取される状態となる（霜取運転モードと同等）。そこで、制御装置Ｃは冷媒量判定モードを複数回の前記霜取運転モードに対して一回実行するものとする。また、毎回実行してもよいが、その場合は前記霜取運転モード＝冷媒量判定モードとなる。 In this refrigerant quantity determination mode, the refrigerant in the evaporator 9 is also sucked and disappears, so that the evaporator 9 is substantially defrosted (equivalent to the defrosting operation mode). Therefore, the control device C executes the refrigerant amount determination mode once for a plurality of defrosting operation modes. Moreover, although you may perform every time, it becomes the said defrost operation mode = refrigerant | coolant amount determination mode in that case.

また、この冷媒量判定モードにおいても凝縮器３７は加熱能力を発揮するので、前述同様に給湯器５６の貯湯タンクに湯が生成されることになる。 Further, in this refrigerant amount determination mode, the condenser 37 exhibits the heating capability, so that hot water is generated in the hot water storage tank of the water heater 56 as described above.

一方、冷媒量判定モードにおいて測定した冷媒量が前記基準値より少ない場合（所定の余裕度を加味して）、制御装置Ｃは冷媒回路１から冷媒が漏洩しているものと判定し、冷凍装置Ｒの運転を停止する（圧縮機６及び圧縮機３６他を停止）。これにより、冷凍装置Ｒを保護する。また、同時に警報器５８を動作させ、冷媒漏洩を使用者に報知することで、冷媒漏洩量を最小限に抑える。 On the other hand, when the refrigerant quantity measured in the refrigerant quantity judgment mode is smaller than the reference value (in consideration of a predetermined margin), the control device C determines that the refrigerant is leaking from the refrigerant circuit 1, and the refrigeration apparatus The operation of R is stopped (the compressor 6 and the compressor 36, etc. are stopped). Thereby, the refrigeration apparatus R is protected. At the same time, the alarm device 58 is operated to notify the user of refrigerant leakage, thereby minimizing the amount of refrigerant leakage.

ここで、既存の冷凍機３に冷媒量判定装置２６を追加して取り付ける場合、既に冷凍機３に内蔵されているレシーバタンク（図１に破線Ａで示す）を取り外す必要がある。その場合は、先ず、冷媒量判定装置２６を冷媒回路１に接続した後、前述した冷媒量判定モードと同様のポンプダウン運転を実行して、レシーバタンクＡ内を含む冷媒回路１内の冷媒を一旦冷媒量判定装置２６のレシーバタンク４２内に回収する。その後、入口側手動弁４６及び出口側手動弁４７を閉じてレシーバタンク４２内に冷媒を封じ込めた状態でレシーバタンクＡを取り外すものとする。これにより、冷媒量判定装置２６をオプションで後付けする際の設置作業が容易となる。 Here, when the refrigerant quantity determination device 26 is additionally attached to the existing refrigerator 3, it is necessary to remove the receiver tank (indicated by the broken line A in FIG. 1) already built in the refrigerator 3. In that case, first, the refrigerant amount determination device 26 is connected to the refrigerant circuit 1, and then the pump-down operation similar to the refrigerant amount determination mode described above is performed, and the refrigerant in the refrigerant circuit 1 including the receiver tank A is discharged. The refrigerant is once collected in the receiver tank 42 of the refrigerant quantity determination device 26. After that, the inlet side manual valve 46 and the outlet side manual valve 47 are closed, and the receiver tank A is removed in a state where the refrigerant is sealed in the receiver tank 42. Thereby, the installation work at the time of retrofitting the refrigerant quantity determination device 26 as an option is facilitated.

以上詳述した如く本発明では制御装置Ｃが冷媒量判定モードを有し、この冷媒量判定モードにおいては電磁弁５０を閉じた状態で圧縮機６及び圧縮機３６を運転し、レシーバタンク４２内に冷媒を回収するポンプダウン運転を実行するので、ポンプダウン運転時にレシーバタンク４２内に回収される冷媒が、凝縮器７を出てカスケード熱交換器４９を通過する過程で冷媒量判定装置２６の蒸発器３９により冷却される。 As described above in detail, in the present invention, the control device C has the refrigerant amount determination mode. In this refrigerant amount determination mode, the compressor 6 and the compressor 36 are operated with the electromagnetic valve 50 closed, and the receiver tank 42 Therefore, the refrigerant recovered in the receiver tank 42 during the pump-down operation exits the condenser 7 and passes through the cascade heat exchanger 49. Cooled by the evaporator 39.

従って、レシーバタンク４２内に回収された冷媒の圧力及び温度を規定の状態とすることができるようになる。また、カスケード熱交換器４９において冷却されることにより、それより上流側の冷媒回路１内の冷媒を残らずレシーバタンク４２内に引き込むことが可能となる。これらにより、レシーバタンク４２内の冷媒量を液面センサ４８にて検出することで、環境条件に左右されずに制御装置Ｃは、液面センサ４８の出力に基づいて極めて精度良くレシーバタンク４２の冷媒量を測定できるようになり、冷媒回路１からの冷媒漏洩を正確に判定することができるようになる。 Therefore, the pressure and temperature of the refrigerant collected in the receiver tank 42 can be brought into a specified state. Further, by being cooled in the cascade heat exchanger 49, it is possible to draw all the refrigerant in the refrigerant circuit 1 upstream from the refrigerant tank 1 into the receiver tank 42. Thus, by detecting the refrigerant amount in the receiver tank 42 with the liquid level sensor 48, the control device C can control the receiver tank 42 with extremely high accuracy based on the output of the liquid level sensor 48 regardless of environmental conditions. The amount of refrigerant can be measured, and the leakage of refrigerant from the refrigerant circuit 1 can be accurately determined.

この場合、レシーバタンク４２は縦長形状とされているので、液面センサ４８によりレシーバタンク４２内の液面の位置で冷媒量を検出する場合に、その分解能を向上させてより正確に冷媒量の測定を行うことが可能となる。 In this case, since the receiver tank 42 has a vertically long shape, when the refrigerant level is detected at the liquid level in the receiver tank 42 by the liquid level sensor 48, the resolution is improved and the refrigerant quantity is more accurately measured. Measurement can be performed.

また、制御装置Ｃが冷媒量判定モードを実行する際に蒸発器９の霜取を行う、即ち、ポンプダウン運転で蒸発器９内の冷媒がレシーバタンク４２に回収され、蒸発器９の温度が上昇する冷媒量判定モードに合わせて蒸発器９の霜取を行うことになるので、効率の良い霜取と冷媒漏洩判定を行うことができるようになる。 Further, when the control device C executes the refrigerant amount determination mode, the evaporator 9 is defrosted, that is, the refrigerant in the evaporator 9 is collected in the receiver tank 42 by the pump-down operation, and the temperature of the evaporator 9 is increased. Since the evaporator 9 is defrosted in accordance with the rising refrigerant amount determination mode, efficient defrosting and refrigerant leakage determination can be performed.

また、制御装置Ｃは冷媒漏洩と判定した場合には、警報器５８により警報を発するので、冷媒漏洩の発生を迅速に使用者に報知し、冷媒漏洩量を最低限に抑えて冷凍能力の悪影響を最小限に抑制することができるようになる。 Further, when the controller C determines that the refrigerant is leaking, the alarm 58 is used to issue an alarm, so that the occurrence of the refrigerant leak is promptly notified to the user, and the refrigerant leakage amount is minimized to adversely affect the refrigerating capacity. Can be minimized.

更に、給湯器５６が設けられており、凝縮器３７からの放熱を利用して給湯器５６における湯の生成を行うので、判定用の冷媒回路４１からの廃熱を利用して給湯を行うことが可能となり、給湯機能の追加による投資（冷媒量判定装置２６を取り付けるための投資）の回収を行うことができるようになる。 Further, a hot water heater 56 is provided, and hot water is generated in the hot water heater 56 using heat radiation from the condenser 37, so that hot water is supplied using waste heat from the refrigerant circuit 41 for determination. This makes it possible to recover the investment by adding the hot water supply function (investment for installing the refrigerant quantity determination device 26).

そして、実施例では冷媒回路４１や水熱交換器５３、ポンプ５２、カスケード熱交換器４９、レシーバタンク４２、液面センサ４８を冷媒量判定装置２６が備えており、更に、この冷媒量判定装置２６のレシーバタンク４２の入口側及び出口側に入口側手動弁４６及び出口側手動弁４７を取り付けているので、ポンプダウン運転を実行して冷媒量判定装置２６のレシーバタンク４２に冷媒を回収した後、入口側手動弁４６と出口側手動弁４７を閉じることで、既存の冷媒回路１のレシーバタンクＡに代えて冷媒量判定装置２６を取り付けた際に、既存のレシーバタンクＡを取り外す作業を容易に行えるようになる。 In the embodiment, the refrigerant amount determination device 26 includes the refrigerant circuit 41, the water heat exchanger 53, the pump 52, the cascade heat exchanger 49, the receiver tank 42, and the liquid level sensor 48. Furthermore, the refrigerant amount determination device Since the inlet side manual valve 46 and the outlet side manual valve 47 are attached to the inlet side and the outlet side of the receiver tank 42 of the No. 26 receiver, the refrigerant is collected in the receiver tank 42 of the refrigerant amount determination device 26 by performing the pump-down operation. After that, by closing the inlet-side manual valve 46 and the outlet-side manual valve 47, when the refrigerant amount determination device 26 is attached instead of the receiver tank A of the existing refrigerant circuit 1, the existing receiver tank A is removed. It becomes easy to do.

尚、実施例では水配管５１を流れる水を直接凝縮器３７の放熱により加熱するようにしたが、それに限らず、ブライン回路を用いて凝縮器３７によりブライン回路内のブラインを加熱し、このブライン回路により給湯器５６内の水を加熱するようにしてもよい。 In the embodiment, the water flowing through the water pipe 51 is directly heated by the heat radiation of the condenser 37. However, the present invention is not limited to this, and the brine in the brine circuit is heated by the condenser 37 using the brine circuit. The water in the water heater 56 may be heated by a circuit.

Ｃ制御装置（制御手段）
Ｒ冷凍装置
１冷媒回路
３冷凍機
５ショーケース
６、３６圧縮機
７、３７凝縮器
９、３９蒸発器
１１、３８膨張弁（絞り手段）
４２レシーバタンク
４６入口側手動弁（入口側弁装置）
４７出口側手動弁（出口側弁装置）
４８液面センサ（冷媒量検出手段）
４９カスケード熱交換器
５０電磁弁（ポンプダウン用弁装置）
５３水熱交換器
５６給湯器 C Control device (control means)
R Refrigeration equipment 1 Refrigerant circuit 3 Refrigerator 5 Showcase 6, 36 Compressor 7, 37 Condenser 9, 39 Evaporator 11, 38 Expansion valve (throttle means)
42 Receiver tank 46 Inlet side manual valve (Inlet side valve device)
47 Outlet side manual valve (Outlet side valve device)
48 Liquid level sensor (refrigerant amount detection means)
49 Cascade heat exchanger 50 Solenoid valve (valve device for pump down)
53 Water heat exchanger 56 Water heater

Claims

In the refrigeration apparatus in which the refrigerant circuit is configured by the compressor, the condenser, the throttle means, and the evaporator,
A determination amount compressor, a determination condenser, a determination throttle means, a refrigerant amount determination device in which a determination refrigerant circuit is configured from a determination evaporator, and a control means,
The refrigerant quantity determination device includes:
A cascade heat exchanger for exchanging heat between the refrigerant exiting the condenser and the determination evaporator;
A receiver tank connected downstream of the cascade heat exchanger and upstream of the throttle means;
A pump-down valve device connected to the refrigerant outlet of the receiver tank;
Refrigerant amount detection means for detecting the amount of refrigerant in the receiver tank,
The control means has a refrigerant amount determination mode,
In the refrigerant amount determination mode, the pump and the determination compressor are operated with the pump-down valve device closed, and a pump-down operation for collecting the refrigerant in the receiver tank is performed.
A refrigerating apparatus, wherein the refrigerant amount in the receiver tank is measured based on the output of the refrigerant amount detection means to determine refrigerant leakage from the refrigerant circuit.

The refrigeration apparatus according to claim 1, wherein the receiver tank has a vertically long shape.

The refrigeration apparatus according to claim 1 or 2, wherein the control means performs defrosting of the evaporator when the refrigerant amount determination mode is executed.

The refrigeration apparatus according to any one of claims 1 to 3, wherein the control unit issues a predetermined alarm when it is determined that the refrigerant leaks in the refrigerant amount determination mode.

Equipped with a water heater,
The refrigeration apparatus according to any one of claims 1 to 4, wherein hot water is generated in the water heater by using heat radiation from the determination condenser.

The refrigeration according to any one of claims 1 to 5, wherein the refrigerant amount determination device includes an inlet side valve device and an outlet side valve device on an inlet side and an outlet side of the receiver tank. apparatus.