JPH09284990A - Compressor protector - Google Patents
Compressor protectorInfo
- Publication number
- JPH09284990A JPH09284990A JP9648696A JP9648696A JPH09284990A JP H09284990 A JPH09284990 A JP H09284990A JP 9648696 A JP9648696 A JP 9648696A JP 9648696 A JP9648696 A JP 9648696A JP H09284990 A JPH09284990 A JP H09284990A
- Authority
- JP
- Japan
- Prior art keywords
- compressor
- relay
- temperature
- temperature rise
- protection device
- 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
Links
Landscapes
- Control Of Positive-Displacement Pumps (AREA)
- Protection Of Generators And Motors (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、空気調和機等に使
用される圧縮機の過大温度上昇を防止する保護装置に関
するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective device for preventing an excessive temperature rise of a compressor used in an air conditioner or the like.
【０００２】[0002]
【従来の技術】従来この種保護装置は、図３及び図４に
示すように温度及び電流に応動して連続的に開閉動作を
行う継電器を圧縮機の外部或いは内部に設置し圧縮機に
直列接続していた。2. Description of the Related Art Conventionally, as shown in FIGS. 3 and 4, a protection device of this type has a relay installed outside or inside of a compressor, which opens and closes continuously in response to temperature and current, and is connected in series to the compressor. I was connected.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、上記従
来の構成では、冷凍サイクル中の冷媒が漏れた場合に、
圧縮機モータ電流が減少してしまうため圧縮機内部の温
度上昇が増加しても継電器がオフしないことがあった。
また、瞬時停電が発生しモータが逆方向に回転した場合
に、ロータリー型圧縮機に於いては、冷媒が循環しない
ため圧縮機内部温度は上昇するがモータ電流は減少する
ため継電器がオフしないことがあった。また更に圧縮機
内部に設置する継電器については、特に信頼性が求めら
れる（長期間に渡り大電流の開閉に耐える）ため形状が
大きくなるという欠点があった。However, in the above conventional structure, when the refrigerant leaks during the refrigeration cycle,
Since the compressor motor current decreases, the relay may not turn off even if the temperature inside the compressor increases.
Also, when the motor rotates in the opposite direction due to an instantaneous power failure, the internal temperature of the compressor rises because the refrigerant does not circulate in the rotary compressor, but the motor current decreases, so the relay should not turn off. was there. Further, the relay installed inside the compressor has a drawback that its shape becomes large because reliability is particularly required (withstands opening and closing of large current for a long period of time).
【０００４】本発明はこのような従来の課題を解決する
ものであり、冷媒が漏れた場合や瞬時停電による逆回転
現象が発生した場合でも圧縮機内部の過大温度上昇を防
止するものである。The present invention solves such a conventional problem, and prevents an excessive temperature rise inside the compressor even when a refrigerant leaks or a reverse rotation phenomenon occurs due to an instantaneous power failure.
【０００５】[0005]
【課題を解決するための手段】上記課題を解決するため
に本発明は、電流に依存せず温度に応動する継電器を圧
縮機の内部に設置し、電流と温度に応動する継電器を圧
縮機の外部に設置するものである。SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is to install a relay that responds to temperature without depending on electric current inside a compressor, and install a relay that responds to current and temperature to the compressor. It is installed outside.
【０００６】[0006]
【発明の実施の形態】上記の課題を解決するため本発明
は、圧縮機の外部に温度及び電流に応動して連続的に開
閉動作を行う第１の継電器と、圧縮機の内部に温度に応
動して連続的に開閉動作を行う第２の継電器を、電源と
圧縮機に直列接続し、主にロックドロータのような急激
な温度上昇に対しては第１の継電器、冷媒漏れや瞬時停
電等のゆっくりした温度上昇に対しては第２の継電器を
作動させるものである。DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to solve the above problems, the present invention relates to a first relay, which is opened and closed continuously in response to temperature and current, outside the compressor, and a temperature inside the compressor. The second relay, which responds to open and close continuously, is connected in series with the power supply and the compressor. The first relay is mainly used for sudden temperature rises such as locked rotors, refrigerant leakage and momentary power failure. The second relay is operated for a slow temperature rise such as.
【０００７】また本発明は、圧縮機内部に設置する継電
器を圧縮機モータの補助巻線に接続し、小型化を図るも
のである。Further, the present invention is intended to reduce the size by connecting the relay installed inside the compressor to the auxiliary winding of the compressor motor.
【０００８】また本発明は、第２の継電器をモータ巻線
に接して配置しモータ巻線の共通ラインに接続するもの
である。Further, according to the present invention, the second relay is arranged in contact with the motor winding and is connected to the common line of the motor winding.
【０００９】また本発明は、第２の継電器を吐出ガス雰
囲気または吐出ガス雰囲気部品に接して配置しモータ巻
線の共通ラインに接続するものである。Further, according to the present invention, the second relay is arranged in contact with the discharge gas atmosphere or the discharge gas atmosphere component and is connected to the common line of the motor windings.
【００１０】また本発明は、第１の継電器を圧縮機の外
郭の近傍に設置し積極的に外郭温度を検出するものであ
る。Further, according to the present invention, the first relay is installed near the outer shell of the compressor to positively detect the outer shell temperature.
【００１１】また本発明は、第１の継電器を圧縮機の外
郭から離れた場所に設置し外郭温度を検出しないように
したものである。Further, according to the present invention, the first relay is installed at a place apart from the outer shell of the compressor so that the outer shell temperature is not detected.
【００１２】また本発明は、第１の継電器の内部に一定
以上の温度で永久的にオープンモードになる熱応動スイ
ッチを付加するものである。Further, according to the present invention, a heat responsive switch that is permanently in an open mode at a temperature above a certain temperature is added inside the first relay.
【００１３】[0013]
【実施例】以下本発明の一実施例について図面を参照し
て説明する。An embodiment of the present invention will be described below with reference to the drawings.
【００１４】（実施例１）図３及び図４は、従来に於け
る圧縮機保護装置のブロック結線図である。同図に於い
て、１は電源装置、２は圧縮機、３は運転用進相コンデ
ンサ、４は電流と周囲温度に応動して連続的に開閉動作
を行う継電器である。図３に於いては、継電器４を圧縮
機２の外部に設置している。図４に於いては、継電器４
を圧縮機２の内部に設置している。このシステムに於い
て、規定冷媒量が確保されかつ正常回転で運転されてい
る場合には、冷凍サイクル負荷増加に伴い運転電流も増
加するので、圧縮機内部温度上昇を継電器４をオフする
事により防止する事が出来る。また圧縮機２がロックド
ロータになった場合にも、運転電流が増大するので同様
に継電器４をオフする事により圧縮機温度上昇を防止す
ることが出来る。(Embodiment 1) FIGS. 3 and 4 are block connection diagrams of a conventional compressor protection device. In the figure, 1 is a power supply device, 2 is a compressor, 3 is a phase advancing capacitor for operation, and 4 is a relay that opens and closes continuously in response to current and ambient temperature. In FIG. 3, the relay 4 is installed outside the compressor 2. In FIG. 4, the relay 4
Is installed inside the compressor 2. In this system, when the specified amount of refrigerant is ensured and the engine is operating at normal speed, the operating current increases as the refrigeration cycle load increases. It can be prevented. Further, even when the compressor 2 becomes a locked rotor, the operating current increases, so that the relay 4 can be turned off to prevent the compressor temperature from rising.
【００１５】しかしながら従来のシステムに於いて、冷
媒が抜けたり或いは瞬時停電に伴う逆回転運転が発生し
た場合には、運転電流が大幅に減少してしまうため圧縮
機２の温度上昇を防止できないという欠点があった。こ
れら欠点を解決する提案（例えば特願平４−２２４２６
９）もされているが不十分である。However, in the conventional system, when the refrigerant escapes or the reverse rotation operation occurs due to the momentary power failure, the operating current is significantly reduced, so that the temperature rise of the compressor 2 cannot be prevented. There was a flaw. A proposal for solving these drawbacks (for example, Japanese Patent Application No. 4-22426).
9) It has been done, but it is insufficient.
【００１６】図１は、本発明に於ける圧縮機保護装置の
ブロック結線図である。同図に於いて、１は電源装置、
２は圧縮機、３は運転用進相コンデンサ、１１は電流と
周囲温度に応動して連続的に開閉動作を行う第１の継電
器、１２は周囲温度に応動して連続的に開閉動作を行う
第２の継電器、１３は圧縮機モータの主巻線、１４は、
圧縮機モータの補助巻線である。FIG. 1 is a block connection diagram of a compressor protection device according to the present invention. In the figure, 1 is a power supply device,
Reference numeral 2 is a compressor, 3 is a phase advancing capacitor for operation, 11 is a first relay that continuously opens and closes in response to current and ambient temperature, and 12 continuously opens and closes in response to ambient temperature The second relay, 13 is the main winding of the compressor motor, and 14 is
It is an auxiliary winding of the compressor motor.
【００１７】まず規定冷媒量が確保されている正常回転
時に於ける動作を説明する。運転中、冷凍サイクル負荷
が増大すると、圧縮機２の内部温度は上昇する。通常こ
の動きは冷凍サイクルの時定数の関係から徐々に進行す
る。この場合には、第２の継電器１２がオフし過大温度
上昇を抑制する。一方、ロックドロータのような大電流
による急激な温度上昇に対しては、第１の継電器１１が
オフし過大温度上昇を抑制する。通常、空気調和機に於
いて、冷凍サイクルの負荷増加（過負荷状態）による第
２の継電器１２の動作する機会は、ロックドロータによ
る第１の継電器１１の動作する機会より遙かに少ない。
そのため、第２の継電器１２の接点容量は小さく設計で
き小型化が図れる。First, the operation during normal rotation in which the specified refrigerant amount is secured will be described. During operation, when the refrigeration cycle load increases, the internal temperature of the compressor 2 rises. Usually, this movement gradually progresses due to the time constant of the refrigeration cycle. In this case, the second relay 12 is turned off to suppress the excessive temperature rise. On the other hand, with respect to a rapid temperature rise due to a large current such as a locked rotor, the first relay 11 is turned off to suppress an excessive temperature rise. Normally, in the air conditioner, the chance of the second relay 12 operating due to the increase in the load of the refrigeration cycle (overload state) is far less than the chance of operating the first relay 11 due to the locked rotor.
Therefore, the contact capacity of the second relay 12 can be designed to be small, and the size can be reduced.
【００１８】次に冷媒抜け或いは瞬時停電による逆回転
運転（ロータリー型圧縮機）が発生した場合に於ける動
作を説明する。運転中、圧縮機２の内部温度は徐々に上
昇する。運転電流は、冷媒循環量が小さく或いは零にな
るので極めて小さくなる。この時には、第２の継電器１
２がオフし過大温度上昇を抑制する。一方、ロックドロ
ータのような大電流による急激な温度上昇に対しては、
第１の継電器１１がオフし過大温度上昇を抑制する。Next, the operation when the reverse rotation operation (rotary type compressor) occurs due to refrigerant loss or momentary power failure will be described. During operation, the internal temperature of the compressor 2 gradually rises. The operating current becomes extremely small because the refrigerant circulation amount is small or becomes zero. At this time, the second relay 1
2 turns off and suppresses excessive temperature rise. On the other hand, for a rapid temperature rise due to a large current like a locked rotor,
The first relay 11 is turned off to suppress an excessive temperature rise.
【００１９】尚、第２の継電器１２の動作について、周
囲温度に応動して連続的に開閉動作をすると説明した
が、多少電流の影響を受けても何ら差し支えない。The operation of the second relay 12 has been described as being continuously opened / closed in response to the ambient temperature, but it may be affected by a little current.
【００２０】図１に於いて、第２の継電器１２は圧縮機
モータの共通ラインに接続している。この場合に於いて
も、従来例（図４）より動作回数を少なくできるため小
型化が図れる。In FIG. 1, the second relay 12 is connected to the common line of the compressor motor. Even in this case, the number of operations can be reduced as compared with the conventional example (FIG. 4), so that the size can be reduced.
【００２１】図２は、圧縮機２の内部に設置する第３の
継電器１５を圧縮機モータの補助巻線に接続した実施例
である。補助巻線電流は、共通ライン電流より遙かに小
さいため更に小型化が図れる。圧縮機２の内部温度が上
昇した場合に、第３の継電器１５がオフする。そうする
とモータ発生トルクは急減するので、ロックドロータ状
態になり共通ライン電流が急激に増加し、その結果第１
の継電器１１がオフし過大温度上昇を抑制する。FIG. 2 shows an embodiment in which the third relay 15 installed inside the compressor 2 is connected to the auxiliary winding of the compressor motor. Since the auxiliary winding current is much smaller than the common line current, further miniaturization can be achieved. When the internal temperature of the compressor 2 rises, the third relay 15 is turned off. Then, the torque generated by the motor is rapidly reduced, and the locked rotor state is established, and the common line current is rapidly increased.
The relay 11 of turns off and suppresses an excessive temperature rise.
【００２２】図１に於いて、圧縮機２の外部に設置した
第１の継電器１１を圧縮機２の外郭に接触させて固定す
ると、過負荷状態に於いて動作する機会が増加し、第２
の継電器１２の負担が軽減できるため、更に第２の継電
器１２の小型化が図れる。In FIG. 1, when the first relay 11 installed outside the compressor 2 is fixed by contacting it with the outer shell of the compressor 2, the chance of operating in an overload state increases, and
Since the load on the relay 12 can be reduced, the size of the second relay 12 can be further reduced.
【００２３】図１に於いて、圧縮機２の外部に設置した
第１の継電器１１を圧縮機２の発熱影響を受けない離れ
た場所に固定すると、実質的に電流にのみ応動して動作
することになり、ロックドロータに対しては第１の継電
器１１、過負荷に対しては第２の継電器１２で完全に分
担して保護するため、過負荷状態に於ける第１の継電器
１１の早動作が防止できる。In FIG. 1, when the first relay 11 installed outside the compressor 2 is fixed at a remote place where it is not affected by the heat generation of the compressor 2, it operates substantially in response to only the current. Therefore, the first relay 11 for the locked rotor and the second relay 12 for the overload are completely shared and protected. The operation can be prevented.
【００２４】図１に於いて、圧縮機２の外部に設置した
第１の継電器１１の内部温度に応動し、一定以上の温度
になった場合に、永久にオープン状態になるよう熱応動
スイッチを附加することにより、圧縮機２或いは第２の
継電器１２が故障する以前に第１の継電器１１が完全オ
フするので、メンテナンスが極めて容易となる。In FIG. 1, in response to the internal temperature of the first relay 11 installed outside the compressor 2, and when the temperature exceeds a certain level, a thermal response switch is set so as to be permanently opened. With the addition, the first relay 11 is completely turned off before the compressor 2 or the second relay 12 fails, so that the maintenance becomes extremely easy.
【００２５】図５は、熱応動スイッチを附加した継電器
の概略構造図である。同図に於いて、２１は可動接点を
有する第１の皿形バイメタル、２２は可動接点、２３は
連結棒、２４は第２の皿形バイメタルである。第１の皿
形バイメタル２１は、約１５０℃で反転するように設定
されている。第２の皿形バイメタル２４は、約２００℃
で反転するように設定されている。通常、ロックドロー
タ保護は第１の皿形バイメタル２１の動作によってなさ
れる。第１の皿形バイメタル２１の動作回数が増加し、
やがて第１の皿形バイメタル２１にクラック等が発生す
ると第１の継電器１１の内部温度は急激に上昇する。こ
の状態になると、第２の皿形バイメタル２４が反転し、
連結棒２３を介して可動接点２２をオフする。第２の皿
形バイメタル２４の反転復帰温度を−２０℃以下に設定
すれば事実上永久オープンとなる。FIG. 5 is a schematic structural diagram of a relay to which a heat responsive switch is added. In the figure, 21 is a first dish-shaped bimetal having a movable contact, 22 is a movable contact, 23 is a connecting rod, and 24 is a second dish-shaped bimetal. The first dish-shaped bimetal 21 is set to be inverted at about 150 ° C. The second plate-shaped bimetal 24 is about 200 ° C
It is set to invert. Locked rotor protection is usually provided by the action of the first dish-shaped bimetal 21. The number of operations of the first dish-shaped bimetal 21 increases,
When a crack or the like occurs in the first dish-shaped bimetal 21 in due course, the internal temperature of the first relay 11 rapidly rises. In this state, the second plate-shaped bimetal 24 is inverted,
The movable contact 22 is turned off via the connecting rod 23. If the inversion return temperature of the second dish-shaped bimetal 24 is set to -20 ° C or lower, it is practically permanently open.
【００２６】[0026]
【発明の効果】上記実施例から明らかなように、電流に
依存せず温度に応動する継電器を圧縮機の内部に設置
し、電流と温度に応動する継電器を圧縮機の外部に設置
することにより、冷媒が抜けた場合や瞬時停電による圧
縮機モータの逆回転運転に対しても、過大な温度上昇を
防止することができる。As is apparent from the above embodiment, by installing a relay that responds to temperature without depending on current inside the compressor, and install a relay that responds to current and temperature outside the compressor. It is possible to prevent an excessive rise in temperature even when the refrigerant runs out or the compressor motor reversely rotates due to an instantaneous power failure.
【００２７】また、本発明は圧縮機の内部に設置する継
電器の開閉回数を少なくできるため、小型化が図れ小容
量圧縮機への適用も可能になった。Further, since the present invention can reduce the number of times of opening and closing the relay installed inside the compressor, it can be downsized and can be applied to a small capacity compressor.
【００２８】また、更に本発明は圧縮機の外部に設置す
る継電器に、一定以上の温度で永久オープンする熱応動
スイッチを附加し、圧縮機本体が故障する以前に継電器
が完全オフし、メンテナンスが極めて容易となった。Further, according to the present invention, a heat responsive switch that is permanently opened at a temperature above a certain level is added to a relay installed outside the compressor so that the relay is completely turned off before maintenance of the compressor body and maintenance is performed. It has become extremely easy.
【図１】本発明の実施例を示すブロック結線図FIG. 1 is a block connection diagram showing an embodiment of the present invention.
【図２】本発明の他の実施例を示すブロック結線図FIG. 2 is a block connection diagram showing another embodiment of the present invention.
【図３】従来の実施例を示すブロック結線図FIG. 3 is a block connection diagram showing a conventional embodiment.
【図４】従来の他の実施例を示すブロック結線図FIG. 4 is a block connection diagram showing another conventional example.
【図５】本発明の実施例を示す第１の継電器の概略構造
図FIG. 5 is a schematic structural diagram of a first relay showing an embodiment of the present invention.
１ 電源 ２ 圧縮機 １１ 第１の継電器 １２ 第２の継電器 １４ モータ補助巻線 １５ 第３の継電器 1 Power Supply 2 Compressor 11 1st Relay 12 2nd Relay 14 Motor Auxiliary Winding 15 3rd Relay
Claims (7)
動して連続的に開閉動作を行う第１の継電器と前記圧縮
機の内部に設置し温度に応動して連続的に開閉動作を行
う第２の継電器を電源と前記圧縮機に直列接続する圧縮
機保護装置。1. A first relay installed outside the compressor to open and close continuously in response to temperature and current, and installed inside the compressor to open and close continuously in response to temperature. A compressor protection device in which a second relay to be performed is connected in series to a power source and the compressor.
動して連続的に開閉動作を行う第１の継電器と電源を前
記圧縮機に直列接続するとともに前記圧縮機の内部に設
置しモータの補助巻線に接続した温度に応動して連続的
に開閉動作を行う第３の継電器から構成される圧縮機保
護装置。2. A motor that is installed outside the compressor and that is connected in series to the compressor and a power source that is opened and closed continuously in response to temperature and current and is installed inside the compressor. A compressor protection device including a third relay that continuously opens and closes in response to the temperature connected to the auxiliary winding.
て配置しモータ巻線の共通ラインに接続する請求項１記
載の圧縮機保護装置。3. The compressor protection device according to claim 1, wherein the second relay is arranged in contact with the compressor motor winding and is connected to a common line of the motor winding.
出ガス雰囲気部品に接して配置しモータ巻線の共通ライ
ンに接続する請求項１記載の圧縮機保護装置。4. The compressor protection device according to claim 1, wherein the second relay is arranged in contact with the discharge gas atmosphere or the discharge gas atmosphere component and is connected to a common line of the motor windings.
できる近傍に配置する請求項１記載の圧縮機保護装置。5. The compressor protection device according to claim 1, wherein the first relay is arranged in the vicinity where the outer temperature of the compressor can be detected.
しない場所に配置する請求項１記載の圧縮機保護装置。6. The compressor protection device according to claim 1, wherein the first relay is arranged at a location where the outer contour of the compressor is not detected.
上の温度に達すると永久にオープン状態になる熱応動ス
イッチを備えた請求項１記載の圧縮機保護装置。7. The compressor protection device according to claim 1, wherein the first relay includes a heat-responsive switch that responds to the internal temperature and becomes permanently open when a temperature above a certain level is reached.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9648696A JPH09284990A (en) | 1996-04-18 | 1996-04-18 | Compressor protector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9648696A JPH09284990A (en) | 1996-04-18 | 1996-04-18 | Compressor protector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09284990A true JPH09284990A (en) | 1997-10-31 |
Family
ID=14166405
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9648696A Pending JPH09284990A (en) | 1996-04-18 | 1996-04-18 | Compressor protector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09284990A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007212023A (en) * | 2006-02-08 | 2007-08-23 | Matsushita Electric Ind Co Ltd | Air conditioning system |
| JP2012115034A (en) * | 2010-11-24 | 2012-06-14 | Tsubaki Emerson Co | Method for preventing single-phase motor reverse rotation, and single-phase motor control circuit |
-
1996
- 1996-04-18 JP JP9648696A patent/JPH09284990A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007212023A (en) * | 2006-02-08 | 2007-08-23 | Matsushita Electric Ind Co Ltd | Air conditioning system |
| JP2012115034A (en) * | 2010-11-24 | 2012-06-14 | Tsubaki Emerson Co | Method for preventing single-phase motor reverse rotation, and single-phase motor control circuit |
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