JPH03129255A

JPH03129255A - Freezer

Info

Publication number: JPH03129255A
Application number: JP1264923A
Authority: JP
Inventors: Shoji Kikuchi; 昭治菊地; Minoru Kasezawa; 加瀬沢　実; Osamu Hakiri; 羽切　治
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1989-10-13
Filing date: 1989-10-13
Publication date: 1991-06-03

Abstract

PURPOSE:To lower a discharged gas temperature as much as possible to prolong the life of a motor and prevent supercooling to ensure the viscosity of a lubricating oil so as to prolong the life of a bearing by disposing an arithmetic unit for detecting a degree of superheat to continuously controlling a flow rate of refrigerant during the operation of the title freezer, and a flow control valve therefor. CONSTITUTION:During the operation of the title freezer, a refrigerant gas having a high temperature and a high pressure, compressed by a compressor 1, is condensed by a condenser 2, decompressed by an expansion valve 3, evaporated by an evaporator 4 to be converted into the refrigerant gas having a low pressure, and then sucked into the compressor 1. During this operation, a discharge pressure signal is inputted into an arithmetic unit 6 by a pressure sensor 7, and a discharged gas temperature signal into said unit 6 by a thermistor 8, wherein both signals inputted are calculated. By comparing a degree of superheat with a preset degree of superheat, the opening degree of a flow control valve 5 for controlling a refrigerant liquid injection rate is varied. By this method, the freezer is actuated so as to always keep a preset degree of superheat and can be operated in high reliability while providing long life for a motor and a bearing.

Description

【発明の詳細な説明】〔産業上の利用分野〕本発明は高圧側に油を保■するスクロール圧縮機をｆｆ
ｇした冷凍装置に関するもので、吐出ガス温度を中間圧
力部への液冷媒導入（以下“液インジェクン璽ン”と１
５゜）し、Ｉｔｌｌｌ呻する際に常に、適正な過熱度に
することで、信頼性の高い冷凍装置を提供することにあ
る。[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a scroll compressor that retains oil on the high pressure side.
This relates to a refrigeration system with a temperature control of discharge gas, which is controlled by introducing liquid refrigerant into an intermediate pressure section (hereinafter referred to as "liquid injection").
The object of the present invention is to provide a highly reliable refrigeration system by always maintaining an appropriate degree of superheating when cooling (5°) and cooling.

[Conventional technology]

従来の装ｒｔは、液インジェク７璽ン量を制御する流ｔ
ａＩ４整弁を、吐出ガス温度が一定になるようにｔｔＴ
ＩＪ呻していた。Conventional equipment has a flow rate that controls the amount of liquid injected.
Set the aI4 valve to ttT so that the discharge gas temperature is constant.
IJ was groaning.

[Problem that the invention seeks to solve]

高圧側に油を保有する圧、１１機エリ成る冷凍装置にお
いて、吐出ガス温度は出来る限り低くする必要があるが
、あまり低くすると油り粘度が低くなり好ましくは無い
ため、過熱度を１ｆｆｌＪ呻することが心安で、丈−モ
スタットにて液インジェク７　、ｌンの電磁弁を開閉制
御すると、電磁弁、テーモスタットの寿命に悪影響を及
ばす。また、圧縮機の容濾制御範囲が大きくなると、固
定式り流を調節器では制御できない、等のこの冷遇どの
問題に対し配慮がされてなかった。In a refrigeration system with oil on the high pressure side and consisting of 11 units, it is necessary to keep the discharge gas temperature as low as possible, but if it is too low, the viscosity of the oil will become low and this is not desirable, so the degree of superheating should be set at 1fflJ. However, if you control the opening and closing of the liquid injector's solenoid valve using the mostat, it will adversely affect the life of the solenoid valve and the mostat. Further, when the capacity control range of the compressor becomes large, no consideration has been given to problems such as the inability to control fixed flow with a regulator.

本発明の目的は、これらの問題点を屏決し、吐出ガス温
度をできる限り低くし、七−夕寿命を助けると共に、冷
遇ぎを防止し、禰の粘度を確保し、軸受けの寿命を助け
ることで、圧縮機としての二人重要ポイントであるモー
タと軸受けの信頼性を向上することにある。The purpose of the present invention is to solve these problems, reduce the temperature of the discharged gas as much as possible, help extend the life of the Tanabata, prevent bad treatment, ensure the viscosity of the wire, and help extend the life of the bearing. The aim is to improve the reliability of the motor and bearing, which are two important points for a compressor.

[Means to solve the problem]

上記目的は％運転中の過熱度を検出し、こ几により訛ｔ
を遅続制御する演算装置と流量弁により達成できる。The above purpose is to detect the degree of superheating during operation, and by this method
This can be achieved using a calculation device and flow valve that performs delayed control.

[Effect]

運転中の吐出側過熱度（ＴｄｓＨ）は（１）弐〇ように
、冷媒の橿頑（Ｎ）、吐出圧力（Ｐｄ）、吐出ガス温度
（Ｔｄ）により求まる。The discharge side superheat degree (TdsH) during operation is determined by the refrigerant strength (N), discharge pressure (Pd), and discharge gas temperature (Td), as shown in (1) 20.

Ｔｄｓｆ（＝ｆ（Ｎ、Ｐｄ、Ｔｄ）　　・・・・・・・
・・・・・・・・・・・・・・（１）また、この吐出圧
力（Ｐｄ）は、圧力センサーにより検出でき、吐出ガス温度（Ｔｄ）はチーきスターにて検出でき、冷
媒の種ｄ　（Ｎ）は、その装置により決まるため予め設
定することにより、マイクロコンビエータにより演算で
きる。Tdsf(=f(N, Pd, Td)...
・・・・・・・・・・・・・・・(1) Also, this discharge pressure (Pd) can be detected by a pressure sensor, and the discharge gas temperature (Td) can be detected by a cheek star. Since the seed d (N) is determined by the device, it can be calculated by the micro combinator by setting it in advance.

また、ここで検出きれた、過熱［（ＴｄｓＨ）により予
め定められた過熱度（’ｌ’ｄｓｆ（ｃ）との比較演算
により、過熱度を変化させる冷媒流量弁の一度を制御す
る。In addition, the refrigerant flow valve that changes the degree of superheat is controlled once by comparing the detected superheat [(TdsH) with the predetermined degree of superheat ('l'dsf(c)).

〔Example〕

以丁、本発明クー実施例を第１図、第２図により説明す
る。An embodiment of the present invention will now be described with reference to FIGS. 1 and 2.

運転中は、圧縮機ｌで圧縮され九高温高圧の冷媒ガスは
凝縮器２によＱ凝縮され、膨張弁８で減圧され、蒸発６
慟で蒸発して低圧の冷媒ガスとなり圧縮機ｌへ吸込まれ
る。During operation, high-temperature, high-pressure refrigerant gas compressed by the compressor 1 is condensed by the condenser 2, depressurized by the expansion valve 8, and evaporated by the evaporator 6.
It evaporates into a low-pressure refrigerant gas and is sucked into the compressor l.

この運転中の吐出圧力（Ｐｄ）は、圧力センサー７、吐
出ガス温度（Ｔｄ）は、チーミスタ８により演莫装ｄ６
に入力され、ここで算出した。過熱度（ＴｄｓＨ）　ト
、予め設定すれた過熱度（Ｔｄｓ）（ｃ）との比較によ
り、欣インジェクシ、ン量を制御する流量弁５の一度を
変化させる。During this operation, the discharge pressure (Pd) is determined by the pressure sensor 7, and the discharge gas temperature (Td) is determined by the team resistor 8, which is determined by the controller d6.
was input and calculated here. Degree of Superheating (TdsH) The flow rate of the flow valve 5 that controls the amount of injection is changed by comparison with the preset degree of superheating (Tds) (c).

これにより常に予め設定された過熱度（ＴｄｓＨｃ）に
なるように動き、信頼性の高い運転ができる〔＠明の効
果〕本発明によれば、冷凍＊ｔｍの屑付櫨境、使用蒸発温度
の変化や％更にインバータ等による容量側−による必要
液インジェクシｌン産が変ｖりでも、安定し７を温熱度
運転を行うことができ、信頼性のｌｆｌい冷凍装置を提
供することができる。As a result, the operation always maintains the preset superheat degree (TdsHc), and highly reliable operation can be achieved. Even if the required liquid injector output changes due to changes, percentages, or the capacity side due to an inverter, etc., stable temperature operation can be performed, and a highly reliable refrigeration system can be provided.

[Brief explanation of the drawing]

第１図は本発明の一実施りリフ）冷凍サイクル系統図と
、制御ｆ７＆置関係図を示Ｔ。第２図は、七の制御フロー図を示す。１・・・圧１８機　　２・・・凝縮器　　８・・・膨張
弁４・・・蒸発６　５・・・ｄｊｔｆｆ　　　ｔｌ・・
・演算装置７・・・圧力七ンｔ−８・・・チーミスタ。第！（２）２７二二FIG. 1 shows a refrigeration cycle system diagram and a control f7 & position relationship diagram according to an embodiment of the present invention. FIG. 2 shows seven control flow diagrams. 1... Pressure 18 machine 2... Condenser 8... Expansion valve 4... Evaporation 6 5... djtff tl...
- Arithmetic device 7...pressure 7-t-8...teamister. No.! (2) 2722

Claims

[Claims]

A fixed scroll and a movable scroll, each having a wrap made of a helical curve such as an involute formed on the end plate, are engaged with each other with the wraps inside, and the movable scroll is rotated relative to the fixed scroll to form a hermetic seal closed by both scroll wraps. It is equipped with a scroll compressor that increases the pressure of the space and is connected to a condenser, a pressure reducer, an evaporator, etc. to form a refrigerant circuit, and an end plate of the fixed scroll is opened to a compression chamber that is intermediate between suction pressure and discharge pressure. In an apparatus that includes a through hole and introduces high pressure liquid refrigerant at the outlet of the condenser through the through hole into the intermediate pressure section, the flow rate of the liquid refrigerant is determined based on the discharge pressure at the outlet of the scroll compressor, the discharge gas temperature, and A refrigeration system characterized by comprising means for controlling based on the degree of superheating of a refrigerant depending on the type of refrigerant.