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JPS5934257B2 - water cooling device - Google Patents

water cooling device

Info

Publication number
JPS5934257B2
JPS5934257B2 JP54086263A JP8626379A JPS5934257B2 JP S5934257 B2 JPS5934257 B2 JP S5934257B2 JP 54086263 A JP54086263 A JP 54086263A JP 8626379 A JP8626379 A JP 8626379A JP S5934257 B2 JPS5934257 B2 JP S5934257B2
Authority
JP
Japan
Prior art keywords
temperature
water temperature
water
compressor
circuit
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.)
Expired
Application number
JP54086263A
Other languages
Japanese (ja)
Other versions
JPS5610643A (en
Inventor
宏明 浜
順二 岡部
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.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric 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 Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP54086263A priority Critical patent/JPS5934257B2/en
Publication of JPS5610643A publication Critical patent/JPS5610643A/en
Publication of JPS5934257B2 publication Critical patent/JPS5934257B2/en
Expired legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00Control issues
    • F25B2600/02Compressor control
    • F25B2600/025Compressor control by controlling speed
    • F25B2600/0251Compressor control by controlling speed with on-off operation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21Temperatures
    • F25B2700/2117Temperatures of an evaporator
    • F25B2700/21171Temperatures of an evaporator of the fluid cooled by the evaporator
    • F25B2700/21172Temperatures of an evaporator of the fluid cooled by the evaporator at the inlet
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21Temperatures
    • F25B2700/2117Temperatures of an evaporator
    • F25B2700/21171Temperatures of an evaporator of the fluid cooled by the evaporator
    • F25B2700/21173Temperatures of an evaporator of the fluid cooled by the evaporator at the outlet

Landscapes

  • Air Conditioning Control Device (AREA)

Description

【発明の詳細な説明】 この発明は、蒸発器で冷却された水温の制御装置の改良
に関するものである。
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a device for controlling the temperature of water cooled by an evaporator.

一般に、水冷却装置では、水の温度制御を水冷却用蒸発
器の入口水温又は、出口水温のいずれかの水温を感知し
て、圧縮機に運転停止の制御信号を出していた。
Generally, in a water cooling device, water temperature is controlled by sensing either the inlet water temperature or the outlet water temperature of a water cooling evaporator, and outputs a control signal to the compressor to stop operation.

第1図は、従来の冷房装置のサイクル図であり、同図に
おいて、1は圧縮機で、この圧縮機1から吐出された高
温高圧のガス冷媒は凝縮器2にて、凝縮液化し絞り装置
3を通過することにより、減圧され、水冷却用蒸発器4
にて蒸発する。
Figure 1 is a cycle diagram of a conventional cooling system. In the figure, 1 is a compressor, and the high temperature and high pressure gas refrigerant discharged from the compressor 1 is condensed and liquefied in a condenser 2, and then 3, the pressure is reduced by passing through the water cooling evaporator 4.
Evaporates at

すなわち、図中点線矢印で示すように冷媒は循環する。That is, the refrigerant circulates as shown by the dotted line arrows in the figure.

そして前記水冷却用蒸発器4にて冷却された冷水は、空
調末端機5にポンプ8にて循環され冷房を行なう。
The cold water cooled by the water cooling evaporator 4 is circulated by a pump 8 to an air conditioning end unit 5 for cooling.

また、循環する冷水は、蒸発器4の水入口部7aに設け
られた温度調節器6にて、水温が制御される。
Further, the temperature of the circulating cold water is controlled by a temperature regulator 6 provided at the water inlet 7a of the evaporator 4.

25は水出口部7bに設けられた凍結防止サーモで、水
温の異常低下時に作動する。
Reference numeral 25 denotes an antifreeze thermostat provided at the water outlet portion 7b, which is activated when the water temperature drops abnormally.

第2図および第3図は蒸発器4の水入口および水出口水
温制御における入口水温と出口水温との関係を示す特性
図であり、とくに第2図および第3図aは蒸発器4へ標
準水量(標準負荷)が循環している場合を、また第2図
および第3図すは蒸発器4への水量が減少(負荷減少)
した場合を示す。
2 and 3 are characteristic diagrams showing the relationship between the inlet water temperature and the outlet water temperature in the water inlet and outlet water temperature control of the evaporator 4. In particular, FIGS. Figures 2 and 3 show the case where the amount of water (standard load) is circulating, and the amount of water to the evaporator 4 decreases (load reduction).
Indicates the case where

このように水入口水温制御で標準負荷時には温度調節器
6によって入口水温すを検出し、ある温度になれば圧縮
機1を運転し、所定温度a低下すれば圧縮機1を停止さ
せる。
In this way, in the water inlet water temperature control, the inlet water temperature is detected by the temperature regulator 6 during standard load, and when the temperature reaches a certain temperature, the compressor 1 is operated, and when the predetermined temperature a decreases, the compressor 1 is stopped.

このときの出口水温dは入口水温すに伴って所定温度中
Cに制御されるので、凍結防止サーモ25が作動して圧
縮機1を停止してしまうこともない。
Since the outlet water temperature d at this time is controlled to a predetermined temperature C as the inlet water temperature increases, the antifreeze thermostat 25 will not operate and the compressor 1 will not be stopped.

ところが、負荷減少時には入口と出口水温差Cが標準負
荷時よりも大きくなる。
However, when the load is reduced, the difference C between the inlet and outlet water temperatures becomes larger than when the load is standard.

すなわち、出口水温dが異常に低下し、温度調節器6が
作動する前に凍結防止サーモ25が作動し、正常な冷房
運転が維持できない。
That is, the outlet water temperature d drops abnormally, the antifreeze thermostat 25 operates before the temperature regulator 6 operates, and normal cooling operation cannot be maintained.

一方、水出口水温制御において、標準負荷のときは第2
図aの場合と同様正常に運転制御できるが、負荷減少時
には出口水温dの異常低下が防止できるが、水出口に設
けられた温度調節器の作動タイミングが早くなって圧縮
機1の発停が頻繁になり、圧縮機1の寿命を縮める原因
となっていた。
On the other hand, in the water outlet water temperature control, the second
As in the case of Figure a, the operation can be controlled normally, but when the load decreases, an abnormal drop in the outlet water temperature d can be prevented, but the operation timing of the temperature regulator installed at the water outlet becomes earlier and the compressor 1 starts and stops. This has become a frequent cause of shortening the life of the compressor 1.

この発明は、上述した欠点を除去するためになされたも
のであって、出口水温で圧縮機を停止させ、この時の入
口水温を記憶しておいて、入口水温が記憶しておいた温
度より所定温度上昇した時点にて、圧縮機を始動させる
事により、適正な、出口温度及び発停間隔を確保するも
のである。
This invention was made in order to eliminate the above-mentioned drawbacks.The compressor is stopped at the outlet water temperature, the inlet water temperature at this time is memorized, and the inlet water temperature is lower than the memorized temperature. By starting the compressor when the temperature rises to a predetermined value, an appropriate outlet temperature and start/stop interval are ensured.

以下、この発明の一実施例について説明する。An embodiment of the present invention will be described below.

第4図は、この発明の一実施例を示す回路図であり、第
5図は、同じく温度検出装置の動作ブ冶ツク図、また、
第6図は、同じく運転特性図である。
FIG. 4 is a circuit diagram showing an embodiment of the present invention, and FIG. 5 is an operational block diagram of the temperature detecting device.
FIG. 6 is also an operating characteristic diagram.

第4図において、9は蒸発器4の水入口部7aに設けら
れた第2の温度検出装置13の感温−1てンサ10は、
同じく水出口部7bに設けられた第1の温度検出装置1
1の感温センサ、12は、第2の温度検出装置13の制
御により付勢される継電器であり、12aは継電器12
のa接点、14は、第1の温度検出装置11の制御によ
り付勢される継電器であり、14bは継電器14のb接
点、17は、運転指令用継電器であり、運転スイッチ1
5により付勢される。
In FIG. 4, reference numeral 9 indicates a temperature sensor 10 of a second temperature detection device 13 provided at the water inlet 7a of the evaporator 4.
The first temperature detection device 1 also provided at the water outlet section 7b
1 is a temperature sensor, 12 is a relay energized by the control of the second temperature detection device 13, and 12a is a relay 12.
A contact 14 is a relay energized by the control of the first temperature detection device 11, 14b is a B contact of the relay 14, 17 is a relay for operation command, and operation switch 1
5.

また、17aは、運転指令用継電器17のa接点である
Moreover, 17a is an a contact of the relay 17 for operation commands.

16は、圧縮機運転用電磁接触器であり、16aは、そ
のa接点である。
16 is an electromagnetic contactor for operating the compressor, and 16a is its a contact.

また25は凍結防止サーモで、水温が異常低下したとき
作動する。
Also, 25 is an anti-freeze thermostat that activates when the water temperature drops abnormally.

第5図において、19,20.21は、第1の温度検出
装置11に設けられた各回路であり、それぞれ、19は
、温度感知部、20は、記憶指令回路、21は、継電器
14を一定時間付勢させる出力回路である。
In FIG. 5, 19, 20, and 21 are respective circuits provided in the first temperature detection device 11, respectively, 19 is a temperature sensing section, 20 is a storage command circuit, and 21 is a circuit for controlling the relay 14. This is an output circuit that energizes for a certain period of time.

また、22,23.24は、第2の温度検出装置13に
設けられた各回路であり、22は、記憶演算部、23は
、継電器12への出力回路で、電磁接触器16の付勢を
確認して出力をOFFする。
Further, 22, 23, 24 are respective circuits provided in the second temperature detection device 13, 22 is a memory calculation section, and 23 is an output circuit to the relay 12, which energizes the electromagnetic contactor 16. Check and turn off the output.

24は、記憶解除指令回路で出力回路23の出力OFF
により作動する。
24 is a memory release command circuit that turns off the output of the output circuit 23.
It is activated by

図中記号Cは、回路α]つながりを示す。Symbol C in the figure indicates a circuit [alpha]] connection.

第6図の符号りは、第1の温度検出装置11の出口水温
動作点であり、Eは前記第2の温度検出装置13が記憶
する入口水温、△tは所定のディファレンシャル、Fは
入口水温動作点である。
The numbers in FIG. 6 are the outlet water temperature operating points of the first temperature detection device 11, E is the inlet water temperature stored in the second temperature detection device 13, Δt is a predetermined differential, and F is the inlet water temperature. This is the operating point.

つぎに、動作について説明する。Next, the operation will be explained.

まず、第5図の第1、および第2の温度検出装置11.
13について説明すると、第1の温度検出装置11にお
いては、感温センサ10で所定の温度を感知すると、温
度感知部19が作動して、第2の温度検出装置13に記
憶指令回路20より、記憶指令を出すと共に、第1の温
度検出装置11に設けられた出力回路21により、継電
器14を付勢し、一定時間後再び消勢させる動作を有し
ている。
First, the first and second temperature detection devices 11 in FIG.
13, in the first temperature detection device 11, when the temperature sensor 10 senses a predetermined temperature, the temperature sensing section 19 is activated, and the second temperature detection device 13 is sent to the storage command circuit 20. In addition to issuing a storage command, the relay 14 is energized by the output circuit 21 provided in the first temperature detection device 11, and the relay 14 is deenergized again after a certain period of time.

また、第2の温度検出装置13においては、水温が上昇
し感温センサ9で所定の温度(第1の温度検出装置11
の記憶指令入力時の入口水温+所定のディファレンシャ
ル△t)を感知すると、記憶演算部22が作動し、前記
第2の温度検出装置13に設けられている出口回路23
により、継電器12を付勢し、そして電磁接触器16を
付勢したのち記憶解除指令回路24を作動させ、前回記
憶した温度を解除するパターン動作を行なう。
In addition, in the second temperature detection device 13, the water temperature rises and the temperature sensor 9 detects a predetermined temperature (the first temperature detection device 11
When the inlet water temperature + predetermined differential △t) at the time of inputting the storage command is sensed, the storage calculation section 22 is activated, and the exit circuit 23 provided in the second temperature detection device 13 is activated.
After energizing the relay 12 and energizing the electromagnetic contactor 16, the memory release command circuit 24 is activated to perform a pattern operation to release the previously stored temperature.

第1および第2の温度検出装置11.13は、かかる動
作をするため、第4図において、電源を投入し、運転ス
イッチ15をONすると継電器17が付勢され、入口水
温が高い場合は、第1および第2の温度検出装置11.
13により、継電器14は消勢、継電器12は、付勢さ
れるため電磁接触器16が付勢され圧縮機1を駆動させ
、以後電磁接触器16の自己保持回路により運転を継続
させるとともに継電器12は消勢する。
Since the first and second temperature detection devices 11.13 perform such operations, in FIG. 4, when the power is turned on and the operation switch 15 is turned on, the relay 17 is energized, and when the inlet water temperature is high, First and second temperature detection devices 11.
13, the relay 14 is de-energized and the relay 12 is energized, so the electromagnetic contactor 16 is energized and drives the compressor 1. Thereafter, the self-holding circuit of the electromagnetic contactor 16 continues the operation, and the relay 12 is energized. disappears.

圧縮機1の運転により、水温低下すると蒸発器4の水出
口部7bに設けられた水温感知センサ10が蒸発器4の
出口水温を感知して、ある所定の設定温度りになると、
継電器14が付勢されるため、その接点14bがOFF
すると、電磁接触器16が消勢され、圧縮機1を運転停
止させるとともに、このときの水温感知センサ9で検出
した入口水温Eを記憶させる。
When the water temperature decreases due to the operation of the compressor 1, the water temperature sensor 10 provided at the water outlet part 7b of the evaporator 4 detects the water temperature at the outlet of the evaporator 4, and when the water temperature reaches a certain preset temperature,
Since the relay 14 is energized, its contacts 14b are OFF.
Then, the electromagnetic contactor 16 is deenergized, the compressor 1 is stopped, and the inlet water temperature E detected by the water temperature sensor 9 at this time is stored.

更に一定時間、例えば5秒後に継電器14を消勢させる
圧縮機1の運転停止により、水温が上昇し、第2の温度
検出装置13で、記憶している入口水温Eより所定のデ
ィファレンシャル△を例えば3°C上昇すると、この温
度Fを水温感知センサ9で検出して継電器12を付勢し
、そして電磁接触器16が付勢されて圧縮機1が運転開
始する。
Furthermore, after a certain period of time, for example, 5 seconds, the relay 14 is deenergized and the compressor 1 is stopped, and the water temperature rises, and the second temperature detection device 13 sets a predetermined differential Δ, for example, from the stored inlet water temperature E. When the temperature rises by 3°C, the water temperature sensor 9 detects this temperature F, energizes the relay 12, and then the electromagnetic contactor 16 is energized, and the compressor 1 starts operating.

電磁接触器16が付勢されると、継電器12が消勢され
る。
When the electromagnetic contactor 16 is energized, the relay 12 is deenergized.

以後第6図の動作パターン図に示すように凍結防止サー
モ25を作動させることなく、しかも圧縮機1の発停間
隔を比較的長くとりながら圧縮機1の運転を継続し、冷
房運転を維持する。
Thereafter, as shown in the operation pattern diagram of FIG. 6, the operation of the compressor 1 is continued without activating the anti-freeze thermostat 25, and the interval between starting and stopping of the compressor 1 is relatively long, thereby maintaining the cooling operation. .

以上のようにこの発明では、所定の出口水温にて圧縮機
を停止させ、この時の入口水温を記憶して、この記憶し
た入口水温に、所定のディファレンシャル△tをプラス
した温度が上昇した時点に圧縮機を運転開始させること
により、従来の入口水温制御の場合のように循環水量の
低下時に発生する、出口水温の異常低下これに伴なう凍
結防止回路(保護装置)の作動また、従来の出口水温制
御の場合のように圧縮機の頻繁な発停による圧縮機焼損
など多々の問題が解消される。
As described above, in this invention, the compressor is stopped at a predetermined outlet water temperature, the inlet water temperature at this time is memorized, and the point in time when the temperature obtained by adding a predetermined differential Δt to the memorized inlet water temperature rises. By starting the compressor at This solves many problems such as compressor burnout due to frequent starting and stopping of the compressor, as in the case of outlet water temperature control.

また、出口水温が安定しかつ信頼性の高い運転を維持で
きる等、実用的効果は極めて高いものである。
In addition, the practical effects are extremely high, such as the ability to maintain stable outlet water temperature and highly reliable operation.

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

第1図は従来の冷房装置のサイクル図、第2図および第
3図は水入口および水出口水温制御における入口と出口
との水温の関係を示す特性図、第4図はこの発明の一実
施例を示す全体回路図、第5図は同じく温度検出装置の
動作ブロック図、第6図はこの発明による水入口および
水出口水温の関係を示す運転特性図である。 なお、図中同一符号は同一または相当部分を示す。 図中、1は圧縮機、2は凝縮器、3は絞り装置、4は蒸
発器、9,10は水温感知センサ、11゜13は第1お
よび第2の温度検出装置である。
Fig. 1 is a cycle diagram of a conventional air conditioner, Figs. 2 and 3 are characteristic diagrams showing the relationship between inlet and outlet water temperatures in water inlet and outlet water temperature control, and Fig. 4 is an embodiment of the present invention. FIG. 5 is an operational block diagram of the temperature detection device, and FIG. 6 is an operating characteristic diagram showing the relationship between water inlet and outlet water temperatures according to the present invention. Note that the same reference numerals in the figures indicate the same or corresponding parts. In the figure, 1 is a compressor, 2 is a condenser, 3 is a throttle device, 4 is an evaporator, 9 and 10 are water temperature sensing sensors, and 11° and 13 are first and second temperature sensing devices.

Claims (1)

【特許請求の範囲】[Claims] 1 圧縮機、凝縮器、膨張装置及び水冷却用蒸発器を順
次連結して構成された冷凍サイクルの前記水冷却用蒸発
器の出口水温を検出し、所定の温度以下に低下したこと
を検出する温度感知部と、その検出信号に基づいて記憶
指令信号を出力する記憶指令回路と、前記検出信号に基
づいて付勢され前記圧縮機を消勢する出力回路とで構成
された第1の温度検出装置、前記水冷却用蒸発器の入口
水温を検出して前記記憶指令信号の入力時における木口
水温に所定温度加算した温度を前記入口水温として記憶
し、この記憶された入口水温と実際の検出入口水温とが
一致した時に一致検出信号を出力する記憶演算回路と、
前記一致検出信号に基づいて前記圧縮機を付勢するとと
もに前記記憶演算回路に記憶された入口水温を解除すべ
く記憶解除指令回路に解除指令を与える出力回路とで構
成された第2の温度検出装置を備えたことを特徴とする
水冷却装置。
1. Detecting the outlet water temperature of the water cooling evaporator of a refrigeration cycle configured by sequentially connecting a compressor, a condenser, an expansion device, and a water cooling evaporator, and detecting that the water temperature has dropped below a predetermined temperature. A first temperature detection comprising a temperature sensing section, a storage command circuit that outputs a storage command signal based on the detection signal, and an output circuit that is energized based on the detection signal and de-energizes the compressor. The device detects the inlet water temperature of the water cooling evaporator, stores the temperature obtained by adding a predetermined temperature to the end water temperature at the time of inputting the storage command signal as the inlet water temperature, and compares this stored inlet water temperature with the actual detected inlet water temperature. a memory calculation circuit that outputs a coincidence detection signal when the temperature matches the water temperature;
a second temperature detection circuit that energizes the compressor based on the coincidence detection signal and provides a release command to a memory release command circuit to release the inlet water temperature stored in the memory calculation circuit; A water cooling device characterized by being equipped with a device.
JP54086263A 1979-07-06 1979-07-06 water cooling device Expired JPS5934257B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP54086263A JPS5934257B2 (en) 1979-07-06 1979-07-06 water cooling device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP54086263A JPS5934257B2 (en) 1979-07-06 1979-07-06 water cooling device

Publications (2)

Publication Number Publication Date
JPS5610643A JPS5610643A (en) 1981-02-03
JPS5934257B2 true JPS5934257B2 (en) 1984-08-21

Family

ID=13881924

Family Applications (1)

Application Number Title Priority Date Filing Date
JP54086263A Expired JPS5934257B2 (en) 1979-07-06 1979-07-06 water cooling device

Country Status (1)

Country Link
JP (1) JPS5934257B2 (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0784969B2 (en) * 1986-11-20 1995-09-13 東京都 Heat pump with auxiliary heater
JPH0617757B2 (en) * 1989-09-14 1994-03-09 清水建設株式会社 Freezing detection method for low temperature cold water production equipment
JP2708053B2 (en) * 1992-07-23 1998-02-04 株式会社日立製作所 Refrigerator temperature controller
JPH074815A (en) * 1993-06-10 1995-01-10 Shinko Metal Prod Kk Water cooling method
JP5106819B2 (en) * 2006-10-20 2012-12-26 三菱重工業株式会社 HEAT SOURCE DEVICE, HEAT SOURCE SYSTEM, AND HEAT SOURCE DEVICE CONTROL METHOD
ITBO20070399A1 (en) * 2007-06-04 2008-12-05 Rhoss S P A METHOD FOR ESTIMATING THE THERMAL LOAD OF A CIRCUIT FOR A SERVICE FLUID OUT OF A REFRIGERATED MACHINE
EP2012069A1 (en) * 2007-06-04 2009-01-07 RHOSS S.p.A. Method for regulating the delivery temperature of a service fluid in output from a refrigerating machine
EP2012068A1 (en) * 2007-06-04 2009-01-07 RHOSS S.p.A. Method for regulating the delivery temperature of a service fluid in output from a refrigerating machine

Also Published As

Publication number Publication date
JPS5610643A (en) 1981-02-03

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