JP3915770B2

JP3915770B2 - Heat pump water heater

Info

Publication number: JP3915770B2
Application number: JP2003372508A
Authority: JP
Inventors: 昌宏尾浜; 竹司渡辺; 啓次郎國本; 宣彦藤原; 立群毛; 誠一安木; 一彦丸本; 隆幸高谷
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2003-10-31
Filing date: 2003-10-31
Publication date: 2007-05-16
Anticipated expiration: 2023-10-31
Also published as: JP2005134070A

Description

本発明はヒートポンプによる給湯機に関するものである。 The present invention relates to a water heater using a heat pump.

従来から、ヒートポンプサイクルを利用した給湯機が提案されており、例えば図７に示すように、貯湯槽を備え、この貯湯槽にあらかじめ溜めたお湯を利用する貯湯型の給湯機が提案されている（例えば特許文献１参照）。すなわち、同図において、圧縮機１、放熱器としての冷媒水熱交換器２、減圧装置３、蒸発器としての空気熱交換器４を接続した冷媒回路と、貯湯槽５、循環ポンプ６、前記冷媒水熱交換器２を接続した水回路などからなり、圧縮機１より吐出された高温高圧の過熱ガス冷媒は冷媒水熱交換器２に流入し、ここで循環ポンプ６から送られてきた水を加熱する。そして、放熱した冷媒は減圧装置３で減圧され、空気熱交換器４に流入にし、ここで大気熱を吸熱して蒸発ガス化し、圧縮機１に戻る。一方、冷媒水熱交換器２で加熱された湯は貯湯槽５の上部に流入し、上から次第に貯湯されていく。この時、冷媒水熱交換器２の水側出口に設けられた沸き上げ温度検出手段７からの信号で回転数制御手段８は循環ポンプ６の回転数を制御して、冷媒水熱交換器２の出口水温(沸き上げ温度)をほぼ一定になるように沸き上げる。そして、前記冷媒水熱交換器２の入口水温が設定値に達すると入水温度検出手段９が検知し、給湯加熱運転を停止するしかし、このような貯湯型の給湯機では、貯湯槽が小さいと湯切れを生じる場合がある。湯切れを生じないためには貯湯槽が大きくなり、それに伴って、必要な設置スペースも大きくなるので、設置の自由度が小さくなるため、設置できない場合が多くなる。 Conventionally, a water heater using a heat pump cycle has been proposed. For example, as shown in FIG. 7, a hot water storage type water heater that includes a hot water storage tank and uses hot water previously stored in the hot water storage tank has been proposed. (For example, refer to Patent Document 1). That is, in the figure, a compressor circuit, a refrigerant water heat exchanger 2 as a radiator, a decompression device 3, a refrigerant circuit connected to an air heat exchanger 4 as an evaporator, a hot water tank 5, a circulation pump 6, The high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 1 flows into the refrigerant water heat exchanger 2, and the water sent from the circulation pump 6 here is composed of a water circuit connected to the refrigerant water heat exchanger 2. Heat. The radiated refrigerant is decompressed by the decompression device 3 and flows into the air heat exchanger 4, where it absorbs atmospheric heat to evaporate and returns to the compressor 1. On the other hand, the hot water heated by the refrigerant water heat exchanger 2 flows into the upper part of the hot water storage tank 5 and is gradually stored from above. At this time, the rotation speed control means 8 controls the rotation speed of the circulation pump 6 by a signal from the boiling temperature detection means 7 provided at the water side outlet of the refrigerant water heat exchanger 2, and the refrigerant water heat exchanger 2. The outlet water temperature (boiling temperature) is boiled so that it is almost constant. When the inlet water temperature of the refrigerant water heat exchanger 2 reaches a set value, the incoming water temperature detecting means 9 detects it and stops the hot water supply heating operation. However, in such a hot water storage type hot water heater, if the hot water storage tank is small There may be a shortage of hot water. In order to prevent the hot water from running out, the hot water storage tank becomes large, and accordingly, the necessary installation space also becomes large. Therefore, the degree of freedom in installation becomes small, and there are many cases where it cannot be installed.

そこで、図８に示すように、貯湯槽を利用することなく、熱交換器で加熱したお湯をそのまま出湯する、瞬間湯沸かし型の給湯機が提案されている（例えば特許文献２参照）。同図において、冷媒回路は圧縮機１より冷媒水熱交換器２の冷媒流路２ａと減圧装置３と空気熱交換器４とを経て、圧縮機１に戻る循環経路により形成されている。また、給水回路は給水管１０より冷媒水熱交換器２の水流路２ｂを経て、給湯端末１１に至る経路により形成されている。しかし、この瞬間湯沸かし型の給湯機は、浴槽の湯張り等の大きな給湯負荷を賄う性能を保証するためには機器を構成するすべての要素部品に対して大きな性能が要求されることになるので、各要素部品および機器全体の大きさや重さが大きくなり、イニィシャルコストが大きくなるという課題がある。さらに、ヒートポンプの特性として、立ち上がりが遅く、所定の給湯温度に達するまでの時間がかかり、快適性に問題がある。 Therefore, as shown in FIG. 8, there has been proposed an instantaneous hot water heater in which hot water heated by a heat exchanger is discharged as it is without using a hot water tank (see, for example, Patent Document 2). In the figure, the refrigerant circuit is formed by a circulation path from the compressor 1 through the refrigerant flow path 2 a of the refrigerant water heat exchanger 2, the decompression device 3, and the air heat exchanger 4 to return to the compressor 1. The water supply circuit is formed by a path from the water supply pipe 10 to the hot water supply terminal 11 through the water flow path 2 b of the refrigerant water heat exchanger 2. However, in order to guarantee the performance to cover a large hot water supply load such as a hot water bath in a bathtub, this instant water heater type requires a large performance for all the component parts constituting the equipment. However, there is a problem that the size and weight of each component part and the entire device are increased, and the initial cost is increased. Furthermore, as a characteristic of the heat pump, the start-up is slow and it takes time to reach a predetermined hot water supply temperature, which causes a problem in comfort.

そこで、図９に示すように、貯湯型の給湯機と瞬間湯沸かし型の給湯機のそれぞれの特性を生かした小型の貯湯槽を備えた瞬間型の給湯機が考えられる。同図において、圧縮機１、放熱器としての冷媒水熱交換器２、減圧手段３、蒸発器としての空気熱交換器４により冷媒回路が構成されている。また、冷媒水熱交換器２は冷媒流路１２とこの冷媒流路１２と熱交換を行う水流路１３とからなる。冷媒回路で加熱することによって貯湯槽に湯を貯湯する沸き上げ運転は、循環ポンプによって貯留槽下部の水を水流路に通水させることによって、加熱し、そして、開閉弁を通って、貯湯槽の上部から高温の湯が貯湯されることによって行われる。また、給湯加熱運転は、給湯端末が開かれて、給水管から供給された市水を冷媒回路で加熱し給湯端末へと通水することによって行われる。しかし、冷媒回路で加熱しそのまま給湯する場合、加熱能力は徐々にしか上昇しないので、給湯端末において、すぐには所定の給湯温度が得られない。そこで、前述の給湯加熱運転の立ち上げ時には、市水を冷媒回路で加熱した比較的低温の湯と貯湯槽上部の高温の湯とを混合手段で混合して所定の湯温にして給湯端末から給湯する。そして、冷媒回路で加熱する水の温度が上昇するに従い、貯湯槽上部の高温の湯の混合比率を少なくする。最終的には、貯湯槽上部の湯は使用せず、すべて冷媒回路で加熱した湯で給湯することになる。 Therefore, as shown in FIG. 9, an instantaneous water heater having a small hot water tank that takes advantage of the characteristics of a hot water storage type water heater and an instantaneous water heater type water heater can be considered. In the figure, a compressor circuit, a refrigerant water heat exchanger 2 as a radiator, a decompression means 3, and an air heat exchanger 4 as an evaporator constitute a refrigerant circuit. The refrigerant water heat exchanger 2 includes a refrigerant channel 12 and a water channel 13 that exchanges heat with the refrigerant channel 12. The boiling operation in which hot water is stored in the hot water tank by heating in the refrigerant circuit is heated by passing the water in the lower part of the storage tank through the water flow path by the circulation pump, and then the hot water tank through the on-off valve. This is done by storing hot water from the top. The hot water supply heating operation is performed by opening the hot water supply terminal, heating the city water supplied from the water supply pipe by the refrigerant circuit, and passing the water to the hot water supply terminal. However, when heating in the refrigerant circuit and supplying hot water as it is, the heating capacity increases only gradually, so that a predetermined hot water supply temperature cannot be obtained immediately at the hot water supply terminal. Therefore, at the start of the hot water supply heating operation described above, a relatively low temperature hot water in which city water is heated by the refrigerant circuit and a high temperature hot water at the top of the hot water storage tank are mixed by a mixing means to obtain a predetermined hot water temperature from the hot water supply terminal. Hot water. And as the temperature of the water heated by the refrigerant circuit rises, the mixing ratio of the hot water in the upper part of the hot water tank is reduced. Eventually, the hot water in the upper part of the hot water tank is not used, and all the hot water is supplied with hot water heated in the refrigerant circuit.

ところで、ヒートポンプサイクルを利用した給湯機の場合、効率の良い加熱運転を行うために冷媒回路を流れる冷媒の循環量の制御が必要である。貯湯型の給湯機では、前述した図７の特許文献１に冷媒循環量の制御について記載されている。以下、その構成、作用について図７を参照しながら説明する。制御手段１６は、外気温度を検出する外気温度検出手段１７と圧縮機１の吐出温度を検出する吐出温度検出手段１８からの信号で、前記吐出温度を所定の吐出温度（目標吐出温度）になるように、減圧装置３の弁開度を制御することによって最適な冷媒循環量になるようにしている。このとき、この目標吐出温度を記憶しているのが目標記憶手段１９である。
特開２０００−３４６４４７号公報特開平２−２２３７６７号公報 By the way, in the case of a water heater using a heat pump cycle, it is necessary to control the circulation amount of the refrigerant flowing through the refrigerant circuit in order to perform an efficient heating operation. In the hot water storage type water heater, the control of the refrigerant circulation amount is described in Patent Document 1 in FIG. 7 described above. The configuration and operation will be described below with reference to FIG. The control means 16 is a signal from the outside temperature detecting means 17 that detects the outside air temperature and the discharge temperature detecting means 18 that detects the discharge temperature of the compressor 1, and the discharge temperature becomes a predetermined discharge temperature (target discharge temperature). As described above, the optimum refrigerant circulation amount is obtained by controlling the valve opening degree of the decompression device 3. At this time, the target storage means 19 stores the target discharge temperature.
JP 2000-346447 A JP-A-2-223767

一日の給湯負荷を考えた時、ほとんどの場合の給湯時間は数分間程度の短時間で終了してしまう。通常、もっとも時間のかかる場合でも、浴槽への湯の落とし込み負荷で約２０分前後である。一方、ヒートポンプサイクルを利用した給湯機の場合、加熱運転を開始して、圧縮機１が起動してから、圧縮機１の吐出温度などが定常状態に達するまで比較的長時間必要とする。だから、給湯端末１１が開かれて、給水管から供給された市水を冷媒回路で加熱し、直接、給湯端末１１へと通水する給湯加熱運転の場合、給湯負荷を検出した後、圧縮機１が起動してから圧縮機１の吐出温度が所定の吐出温度に上昇する前に、給湯時間が終了してしまう。例えば、前述した吐出温度による冷媒循環量の制御をした場合について、図１０を用いて説明をする。同図において、横軸に運転を起動してからの運転時間をとり、縦軸に圧縮機１の周波数、吐出圧力、吐出温度および減圧装置の弁開度をとり、起動後の運転時間に対する圧縮機の周波数、吐出圧力、吐出温度および減圧装置の弁開度の変化を説明したものである。給湯加熱運転が始まると圧縮機１が起動する。一般に、圧縮機１としてはインバータ制御で能力可変のものが使用されることが多い。そこで、起動後、徐々に運転周波数を上昇していき、目標の運転周波数に達する。この時、吐出温度は比較的ゆっくりと上昇するため、目標吐出温度になかなか到達しないので、減圧装置３の弁開度を徐々に絞っていく。それに伴い、吐出圧力も上昇し、圧縮機１の圧縮比が大きくなり、運転効率が低下する。場合によっては、急激に圧力が上昇し、圧力の保護装置（図示せず）が動作して、運転を停止してしまうこともある。結局、適正な冷媒循環量ができないので、運転効率が悪くなるという課題を有している。 When considering the daily hot water supply load, the hot water supply time in most cases ends in a short time of about several minutes. Usually, even when it takes the most time, it takes about 20 minutes due to the dropping load of hot water into the bathtub. On the other hand, in the case of a water heater using a heat pump cycle, a relatively long time is required until the discharge temperature of the compressor 1 reaches a steady state after starting the heating operation and starting the compressor 1. Therefore, in the case of hot water heating operation in which the hot water supply terminal 11 is opened and the city water supplied from the water supply pipe is heated in the refrigerant circuit and directly passed to the hot water supply terminal 11, the hot water supply load is detected, and then the compressor The hot water supply time ends before the discharge temperature of the compressor 1 rises to a predetermined discharge temperature after the 1 is started. For example, the case where the refrigerant circulation amount is controlled by the discharge temperature described above will be described with reference to FIG. In the figure, the horizontal axis indicates the operation time after starting the operation, the vertical axis indicates the frequency of the compressor 1, the discharge pressure, the discharge temperature, and the valve opening of the pressure reducing device, and compression with respect to the operation time after the start. It explains changes in the machine frequency, discharge pressure, discharge temperature, and valve opening of the pressure reducing device. When the hot water supply heating operation starts, the compressor 1 is started. In general, the compressor 1 is often used with a variable capacity by inverter control. Therefore, after starting, the operating frequency is gradually increased to reach the target operating frequency. At this time, since the discharge temperature rises relatively slowly, the target discharge temperature is not easily reached. Therefore, the valve opening of the decompression device 3 is gradually reduced. Along with this, the discharge pressure also increases, the compression ratio of the compressor 1 increases, and the operating efficiency decreases. In some cases, the pressure suddenly increases, and a pressure protection device (not shown) is operated to stop the operation. Eventually, there is a problem that the operation efficiency is deteriorated because an appropriate amount of refrigerant circulation cannot be achieved.

また、一般に圧縮機１の吐出温度を測定するために、圧縮機１の出口と冷媒水熱交換器２の冷媒流路１２入口とを接続する配管の表面をサーミスタなどで温度検出する場合が多い。この場合、一旦加熱運転を終了後、すぐに再度、加熱運転を起動するとき、前記サーミスタが設置部の(前回の運転で加熱されて高温になったままの)配管の温度を検出してしまい、正しい吐出温度に基づく適正な冷媒循環量ができないので、効率が悪くなるという課題も有している。 In general, in order to measure the discharge temperature of the compressor 1, the temperature of the surface of the pipe connecting the outlet of the compressor 1 and the inlet of the refrigerant flow path 12 of the refrigerant water heat exchanger 2 is often detected with a thermistor or the like. . In this case, when the heating operation is started again immediately after finishing the heating operation, the thermistor detects the temperature of the pipe of the installation section (heated in the previous operation and remains at a high temperature). In addition, since an appropriate refrigerant circulation amount based on the correct discharge temperature cannot be obtained, there is a problem that efficiency is deteriorated.

本発明は上記課題を解決するもので、比較的運転時間が長く、冷媒水熱交換器の水流路の出口の水温度が高い沸き上げ運転と、比較的運転時間が短く、冷媒水熱交換器の水流路の出口の水温度が低い給湯加熱運転に対して、それぞれ最適な冷媒循環量に制御をすることによって、運転の高効率化をはかることを主目的とするものである。 SUMMARY OF THE INVENTION The present invention solves the above-described problem, and a boiling operation in which the operation time is relatively long, the water temperature at the outlet of the water flow path of the refrigerant water heat exchanger is high, and the operation time is relatively short. The main purpose is to increase the efficiency of the operation by controlling the coolant circulation amount to be optimal for the hot water supply heating operation in which the water temperature at the outlet of the water flow path is low.

前記従来の課題を解決するために、本発明のヒートポンプ給湯機は、圧縮機、放熱器としての冷媒水熱交換器、減圧装置、蒸発器としての空気熱交換器を有する冷媒回路と、前記放熱器と熱交換する前記冷媒水熱交換器に設けられた水流路に市水を供給する給水管と
、前記水流路から給湯端末へと通水するように接続する給湯回路と、前記冷媒回路で加熱した温水を貯湯する貯湯槽と、前記圧縮機の吐出温度を検出する吐出温度検出手段とを備え、前記冷媒水熱交換器で加熱された湯を前記貯湯槽に貯湯する沸き上げ運転と、前記冷媒水熱交換器で加熱された湯を給湯端末へ通水する給湯加熱運転の２つの運転動作を有し、前記沸き上げ運転時よりも前記給湯加熱運転時の方が、前記圧縮機から吐出する冷媒の温度を低く設定するものである。 In order to solve the conventional problems, a heat pump water heater of the present invention includes a compressor, a refrigerant water heat exchanger as a radiator, a decompression device, a refrigerant circuit having an air heat exchanger as an evaporator, and the heat dissipation. A water supply pipe for supplying city water to a water flow path provided in the refrigerant water heat exchanger for exchanging heat with a heater, a hot water supply circuit connected so as to pass water from the water flow path to a hot water supply terminal, and the refrigerant circuit A hot water storage tank for storing heated hot water, and a discharge temperature detecting means for detecting a discharge temperature of the compressor; a boiling operation for storing hot water heated by the refrigerant water heat exchanger in the hot water storage tank; It has two operation operations of a hot water supply heating operation for passing hot water heated by the refrigerant water heat exchanger to a hot water supply terminal, and the hot water supply heating operation is more effective than the boiling operation from the compressor. it is for setting the temperature of the refrigerant discharged low

これによって、比較的運転時間が長く、冷媒水熱交換器の水流路の出口の水温度が高い沸き上げ運転と、比較的運転時間が短く、冷媒水熱交換器の水流路の出口の水温度が低い給湯加熱運転に対して、それぞれ最適な冷媒循環量に制御をすることによって、運転の高効率化をはかることができる。 As a result, a boiling operation with a relatively long operation time and a high water temperature at the outlet of the water flow path of the refrigerant water heat exchanger, and a water temperature at the outlet of the water flow path of the refrigerant water heat exchanger with a relatively short operation time. For the hot water supply heating operation with low temperature, the efficiency of the operation can be increased by controlling the refrigerant circulation amount to be optimum.

本発明のヒートポンプ給湯機は、比較的運転時間の長い沸き上げ運転時には所定の吐出温度になるように冷媒循環量を制御するので加熱運転の効率の向上を図ることができる。 Since the heat pump water heater of the present invention controls the refrigerant circulation amount so as to reach a predetermined discharge temperature during a boiling operation with a relatively long operation time, it is possible to improve the efficiency of the heating operation.

本発明は各請求項に記載の形態で実施できるものであり、第１の発明は、圧縮機、放熱器としての冷媒水熱交換器、減圧装置、蒸発器としての空気熱交換器を有する冷媒回路と、前記放熱器と熱交換する前記冷媒水熱交換器に設けられた水流路に市水を供給する給水管と、前記水流路から給湯端末へと通水するように接続する給湯回路と、前記冷媒回路で加熱した温水を貯湯する貯湯槽と、前記圧縮機の吐出温度を検出する吐出温度検出手段とを備え、前記冷媒水熱交換器で加熱された湯を前記貯湯槽に貯湯する沸き上げ運転と、前記冷媒水熱交換器で加熱された湯を給湯端末へ通水する給湯加熱運転の２つの運転動作を有し、前記沸き上げ運転時よりも前記給湯加熱運転時の方が、前記圧縮機から吐出する冷媒の温度を低く設定するため、沸き上げ運転と給湯加熱運転ともに加熱運転の効率の向上になる。 The present invention can be implemented in the form described in each claim, and the first invention is a refrigerant having a compressor, a refrigerant water heat exchanger as a radiator, a decompression device, and an air heat exchanger as an evaporator. A water supply pipe that supplies city water to a water flow path provided in the refrigerant water heat exchanger that exchanges heat with the radiator, and a hot water supply circuit that is connected to pass water from the water flow path to the hot water supply terminal. A hot water storage tank for storing hot water heated by the refrigerant circuit; and a discharge temperature detecting means for detecting a discharge temperature of the compressor, wherein hot water heated by the refrigerant water heat exchanger is stored in the hot water storage tank. There are two operation operations, a boiling operation and a hot water heating operation for passing hot water heated by the refrigerant water heat exchanger to a hot water supply terminal, and the hot water heating operation is more than the boiling operation. , order to set the temperature of the refrigerant discharged from the compressor low, Made in improving the efficiency of the pressurized heat operation to increase operation and the hot water supply heating operation both can.

第２の発明のヒートポンプ給湯機は、特に第１の発明において、沸き上げ運転時には、圧縮機の吐出温度が所定の吐出温度になるように、減圧装置の弁開度を制御し、給湯加熱運転時には、起動時の循環量制御後は、前記減圧装置の弁開度を所定の弁開度に設定することにより、効率の良い加熱運転ができる。 In the heat pump water heater of the second invention, particularly in the first invention, during the boiling operation, the valve opening of the decompression device is controlled so that the discharge temperature of the compressor becomes a predetermined discharge temperature, and the hot water supply heating operation is performed. Sometimes, after the circulation amount control at the start-up, an efficient heating operation can be performed by setting the valve opening of the pressure reducing device to a predetermined valve opening.

第３の発明のヒートポンプ給湯機は、特に第２の発明において、給湯加熱運転が起動して所定の時間経過後、圧縮機の吐出温度が所定の吐出温度になるように前記減圧装置の弁開度を制御することにより、給湯加熱運転が長時間続いた場合は、吐出温度制御を行うので効率の良い運転が可能になる。 In the heat pump water heater of the third invention, particularly in the second invention, the valve opening of the pressure reducing device is set so that the discharge temperature of the compressor becomes a predetermined discharge temperature after a hot water heating operation is started and a predetermined time has elapsed. By controlling the degree, when the hot water supply heating operation continues for a long time, the discharge temperature control is performed, so that an efficient operation is possible.

第４の発明のヒートポンプ給湯機は、特に第２の発明において、所定の弁開度を、圧縮機の周波数、外気温度、熱交換器の入口温度、熱交換器の出口温度のうち、複数の情報に基づいて決定するので、給湯加熱運転の性能を決定する諸条件が変化しても効率の良い運転が可能となる。 The heat pump water heater of the fourth invention is the heat pump water heater of the second invention , in particular, in the second invention, the predetermined valve opening is a plurality of compressor frequency, outside air temperature, heat exchanger inlet temperature, heat exchanger outlet temperature. Since it determines based on information, even if various conditions which determine the performance of hot water supply heating operation change, efficient operation is attained.

第５の発明のヒートポンプ給湯機は、特に第１〜第４の発明において、冷媒回路に用いる冷媒を二酸化炭素とし、高圧側では臨界圧を超える状態で運転するので、高温高効率化と地球環境保全をはかることができる。 In the heat pump water heater of the fifth invention, particularly in the first to fourth inventions, the refrigerant used in the refrigerant circuit is carbon dioxide, and the high pressure side is operated in a state exceeding the critical pressure. Conservation can be achieved.

以下、本発明の実施の形態について、図面を参照しながら説明する。なお、この実施の形態によって本発明が限定されるものではない。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

（実施の形態１）
図１は本発明の第１の実施の形態におけるヒートポンプ給湯機の構成図、図２は同ヒートポンプ給湯機の運転時間に対する圧縮機の周波数と吐出圧力と吐出温度と減圧装置の弁開度との変化を示す説明図である。なお、従来例で説明した図７〜図９と同じ構成部材には同一符号を用い説明を省略する。 (Embodiment 1)
FIG. 1 is a block diagram of the heat pump water heater in the first embodiment of the present invention, and FIG. 2 shows the frequency of the compressor, the discharge pressure, the discharge temperature, and the valve opening of the pressure reducing device with respect to the operation time of the heat pump water heater. It is explanatory drawing which shows a change. In addition, the same code | symbol is used for the same component as FIGS. 7-9 demonstrated in the prior art example, and description is abbreviate | omitted.

冷媒の循環量を制御する場合、その制御対象となる、冷凍サイクルの状態を決める物理量として、圧縮機１の吐出温度や吐出圧力がある。さらに、冷凍サイクルの状態を決める物理量から計算される圧縮機１の吸入冷媒の過熱度などがある。そこで、図１においては、一例として、制御対象を圧縮機１の吐出温度を用いた場合を示す。すなわち、冷媒循環量制御手段２０は、減圧装置３と吐出温度検出手段１８と制御装置１６とから成り立っている。また、圧縮機１として、インバータ制御などで能力可変のものであれば、冷媒循環量制御手段２０のなかに、圧縮機１を含んでも良い。さらに、冷媒としては、高圧側の冷媒圧力が臨界圧力以上となる二酸化炭素を用いている。 When controlling the circulation amount of the refrigerant, there are a discharge temperature and a discharge pressure of the compressor 1 as physical quantities that determine the state of the refrigeration cycle, which is a control target. Furthermore, there is the degree of superheat of the refrigerant sucked in the compressor 1 calculated from the physical quantity that determines the state of the refrigeration cycle. Therefore, in FIG. 1, as an example, a case where the discharge temperature of the compressor 1 is used as a control target is shown. That is, the refrigerant circulation amount control means 20 includes the decompression device 3, the discharge temperature detection means 18, and the control device 16. Further, the compressor 1 may be included in the refrigerant circulation amount control means 20 as long as the compressor 1 has variable capacity by inverter control or the like. Further, as the refrigerant, carbon dioxide whose refrigerant pressure on the high pressure side is equal to or higher than the critical pressure is used.

動作、作用について説明する。まず、冷媒回路で加熱することによって貯湯槽に湯を貯湯する沸き上げ運転について説明する。この場合、制御手段１６は、減圧装置３の弁開度を所定の起動弁開度に設定し、さらに、必要な加熱能力を得るために圧縮機１の所定の運転周波数を設定して、圧縮機１を起動する。そして、圧縮機１が前記所定の運転周波数に達した後、所定の条件が成り立てば、圧縮機１の吐出温度を検出する吐出温度検出手段１８からの信号で、前記吐出温度を所定の吐出温度（目標吐出温度）になるように、減圧装置３の弁開度を制御することによって最適な冷媒循環量になるようにしている。なお、前記所定の条件としては、圧縮機１の起動後の運転時間が所定の時間に達するか、吐出温度が安定するか、吐出温度が所定の吐出温度に達するかなどである。 The operation and action will be described. First, a boiling operation for storing hot water in a hot water tank by heating in a refrigerant circuit will be described. In this case, the control means 16 sets the valve opening of the decompression device 3 to a predetermined starting valve opening, and further sets a predetermined operating frequency of the compressor 1 to obtain a required heating capacity, The machine 1 is started. If the predetermined condition is satisfied after the compressor 1 reaches the predetermined operating frequency, the discharge temperature is detected by a signal from the discharge temperature detecting means 18 for detecting the discharge temperature of the compressor 1. By controlling the valve opening degree of the pressure reducing device 3 so as to be (target discharge temperature), an optimum refrigerant circulation amount is obtained. The predetermined condition includes whether the operation time after starting up the compressor 1 reaches a predetermined time, whether the discharge temperature is stable, whether the discharge temperature reaches a predetermined discharge temperature, or the like.

次に、給湯端末が開かれて、給水管から供給された市水を冷媒回路で加熱し給湯端末へと通水する給湯加熱運転について説明する。制御手段１６は、減圧装置３の弁開度を所定の起動弁開度に設定し、さらに、必要な加熱能力を得るために圧縮機１の所定の運転周波数を設定し、圧縮機１を起動する。そして、圧縮機１が前記所定の運転周波数に達した後、減圧装置３の弁開度を所定の弁開度に設定する。なお、ヒートポンプによる加熱運転の場合、その効率などの性能は、蒸発器や放熱器において熱交換する媒体の条件で決定される。すなわち、圧縮機の周波数、外気温度、冷媒水熱交換器２の水流路１３の入口温度、冷媒水熱交換器２の水流路１３の出口温度、減圧装置３の弁開度などである。そこで、これらの相互の関係を予め求めておいて、その情報を制御手段１６に記憶させておき、減圧装置３の弁開度を決定すればよい。このとき、すべての情報に基づいて、減圧装置３の弁開度を決定しなくても、特に影響の大きい情報を基に決定しても良い。たとえば、圧縮機の周波数、外気温度、冷媒水熱交換器２の水流路１３の出口温度などである。 Next, a hot water supply heating operation in which the hot water supply terminal is opened and the city water supplied from the water supply pipe is heated by the refrigerant circuit and passed to the hot water supply terminal will be described. The control means 16 sets the valve opening of the decompression device 3 to a predetermined starting valve opening, sets a predetermined operating frequency of the compressor 1 to obtain a required heating capacity, and starts the compressor 1 To do. Then, after the compressor 1 reaches the predetermined operating frequency, the valve opening of the decompression device 3 is set to a predetermined valve opening. In the case of a heating operation by a heat pump, the performance such as efficiency is determined by the condition of the medium for heat exchange in the evaporator or the radiator. That is, the frequency of the compressor, the outside air temperature, the inlet temperature of the water passage 13 of the refrigerant water heat exchanger 2, the outlet temperature of the water passage 13 of the refrigerant water heat exchanger 2, the valve opening degree of the decompression device 3, and the like. Therefore, these mutual relationships are obtained in advance, and the information is stored in the control means 16, and the valve opening degree of the pressure reducing device 3 is determined. At this time, the valve opening degree of the decompression device 3 may not be determined based on all the information, but may be determined based on information having a particularly large influence. For example, the frequency of the compressor, the outside air temperature, the outlet temperature of the water flow path 13 of the refrigerant water heat exchanger 2, and the like.

上記のように、比較的運転時間が長く、冷媒水熱交換器２の出口の水温度が高い沸き上げ運転時には圧縮機１の吐出温度を所定の吐出温度（目標吐出温度）になるように減圧装置３の弁開度を制御し、比較的運転時間が短く、冷媒水熱交換器２の出口の水温度が低い給湯加熱運転時には減圧装置３の弁開度を所定の弁開度に設定するため、沸き上げ運転、給湯加熱運転それぞれに対して、最適な冷媒循環量になるように制御するので効率の良い運転ができる。 As described above, during the heating operation in which the operation time is relatively long and the water temperature at the outlet of the refrigerant water heat exchanger 2 is high, the discharge temperature of the compressor 1 is reduced to a predetermined discharge temperature (target discharge temperature). The valve opening degree of the apparatus 3 is controlled, and the valve opening degree of the pressure reducing device 3 is set to a predetermined valve opening degree during hot water supply heating operation in which the operation time is relatively short and the water temperature at the outlet of the refrigerant water heat exchanger 2 is low. Therefore, since the control is performed so that the refrigerant circulation amount is optimum for each of the boiling operation and the hot water supply heating operation, an efficient operation can be performed.

給湯端末が開かれて、給水管から供給された市水を冷媒回路で加熱し給湯端末へと通水する給湯加熱運転は前述したように、ほとんどの場合、短時間で終了してしまう。しかし、浴槽への湯の落とし込みなどは比較的長時間になる。このような場合には、給湯加熱運転が起動して所定の時間経過後、圧縮機１の吐出温度が所定の吐出温度になるように減圧装置３の弁開度を制御すればよい。図２は横軸に圧縮機１が起動してからの運転時間をと
り、縦軸に圧縮機１の周波数と吐出圧力と吐出温度と減圧装置３の弁開度をとって、運転時間に対する圧縮機１の周波数と吐出圧力と吐出温度と減圧装置３の弁開度の変化を示したものである。この場合、制御手段１６は、減圧装置３の弁開度を所定の起動弁開度に設定し、さらに、必要な加熱能力を得るために圧縮機１の所定の運転周波数を設定して、圧縮機１を起動する。そして、圧縮機１が前記所定の運転周波数に達した後、減圧装置３の弁開度を所定の弁開度に設定する。給湯時間が続き、給湯加熱運転時間が所定の時間以上経過すれば、圧縮機１の吐出温度を検出する吐出温度検出手段１８からの信号で、前記吐出温度を所定の吐出温度（目標吐出温度）になるように、減圧装置３の弁開度を制御する。このようにすれば、給湯加熱運転が長時間続いた場合でも、最適な冷媒循環量が得られ、効率の良い運転ができる。 As described above, the hot water supply heating operation in which the hot water supply terminal is opened and the city water supplied from the water supply pipe is heated by the refrigerant circuit and passed through the hot water supply terminal is almost completed in a short time. However, dropping hot water into the bathtub takes a relatively long time. In such a case, the valve opening degree of the decompression device 3 may be controlled so that the discharge temperature of the compressor 1 becomes a predetermined discharge temperature after the hot water supply heating operation is started and a predetermined time elapses. In FIG. 2, the horizontal axis indicates the operation time after the compressor 1 is started, and the vertical axis indicates the frequency of the compressor 1, the discharge pressure, the discharge temperature, and the valve opening degree of the decompression device 3, and compression with respect to the operation time The change of the frequency of the machine 1, discharge pressure, discharge temperature, and the valve opening degree of the decompression device 3 is shown. In this case, the control means 16 sets the valve opening of the decompression device 3 to a predetermined starting valve opening, and further sets a predetermined operating frequency of the compressor 1 to obtain a required heating capacity, The machine 1 is started. Then, after the compressor 1 reaches the predetermined operating frequency, the valve opening of the decompression device 3 is set to a predetermined valve opening. If the hot water supply time continues and the hot water heating operation time elapses a predetermined time or more, the discharge temperature is detected by a signal from the discharge temperature detecting means 18 that detects the discharge temperature of the compressor 1 and the predetermined discharge temperature (target discharge temperature). The valve opening of the decompression device 3 is controlled so that In this way, even when the hot water supply heating operation continues for a long time, the optimum refrigerant circulation amount can be obtained, and an efficient operation can be performed.

沸き上げ運転は貯湯槽５に高温の湯（一般に６５〜９０℃）を貯める運転であり、給湯加熱運転は直接給湯端末１１で湯を使うために、中温の湯（一般に４２℃前後）を作る運転である。また、沸き上げ運転と給湯加熱運転とでは、冷媒回路での加熱能力がほぼ一定であるとするならば、冷媒水熱交換器２の水流路１３を流れる水の流量は、給湯加熱運転の方が当然多くなる。さらに、冷媒水熱交換器２では、通常、冷媒と水とは対向流となるように冷媒流路１２と水流路１３とを構成する。このとき、冷媒流路１２の入口温度（冷媒入口温度）と水流路１３の出口温度（水出口温度）との差には、運転効率を考慮した場合、最適値がある。だから、高温の湯を作る沸き上げ運転と中温の湯を作る給湯加熱運転とでは、最適な冷媒循環量が得られる所定の吐出温度（目標吐出温度）が異なることになる。そこで、沸き上げ運転時よりも給湯加熱運転時の方が、所定の吐出温度（目標吐出温度）を低く設定すると、効率の良い運転が可能となる。言い換えれば、冷媒水熱交換器２の水流路１３を流れる水の流量が多いほど、所定の吐出温度（目標吐出温度）を低く設定する方が、効率の良い運転ができることになる。 The boiling operation is an operation in which hot water (generally 65 to 90 ° C.) is stored in the hot water storage tank 5, and the hot water heating operation is to use medium hot water (generally around 42 ° C.) in order to use the hot water directly at the hot water supply terminal 11. Driving. Further, in the boiling operation and the hot water supply heating operation, if the heating capacity in the refrigerant circuit is substantially constant, the flow rate of water flowing through the water flow path 13 of the refrigerant water heat exchanger 2 is equal to that in the hot water supply heating operation. Naturally increases. Further, in the refrigerant water heat exchanger 2, the refrigerant flow path 12 and the water flow path 13 are usually configured so that the refrigerant and water are opposed to each other. At this time, the difference between the inlet temperature of the refrigerant channel 12 (refrigerant inlet temperature) and the outlet temperature of the water channel 13 (water outlet temperature) has an optimum value when operating efficiency is considered. Therefore, a predetermined discharge temperature (target discharge temperature) at which an optimum refrigerant circulation amount is obtained is different between a boiling operation for producing high-temperature hot water and a hot-water supply heating operation for producing medium-temperature hot water. Therefore, if the predetermined discharge temperature (target discharge temperature) is set lower in the hot water supply heating operation than in the boiling operation, an efficient operation is possible. In other words, the more the flow rate of water flowing through the water flow path 13 of the refrigerant water heat exchanger 2 is, the more efficiently the operation can be performed when the predetermined discharge temperature (target discharge temperature) is set lower.

（実施の形態２）
図３は本発明の第２の実施の形態におけるヒートポンプ給湯機の構成図である。なお、本発明の第１の実施の形態で説明した図１と同じ構成部材には同一符号を用い説明を省略する。図１と異なる点は、冷媒の循環量の制御対象として、冷凍サイクルの状態を決める物理量である圧縮機１の吐出圧力としたことである。つまり、冷媒循環量制御手段２０として，圧縮機１の吐出圧力を検出する吐出圧力検出手段２１と減圧装置３と制御装置１６とを用いたことである。第１の実施の形態と同様、冷媒循環量制御手段２０のなかに、圧縮機１を含んでも良い。 (Embodiment 2)
FIG. 3 is a configuration diagram of a heat pump water heater in the second embodiment of the present invention. In addition, the same code | symbol is used for the same component as FIG. 1 demonstrated in the 1st Embodiment of this invention, and description is abbreviate | omitted. The difference from FIG. 1 is that the discharge pressure of the compressor 1, which is a physical quantity that determines the state of the refrigeration cycle, is set as the control target of the refrigerant circulation amount. That is, as the refrigerant circulation amount control means 20, the discharge pressure detection means 21 that detects the discharge pressure of the compressor 1, the decompression device 3, and the control device 16 are used. Similarly to the first embodiment, the compressor 1 may be included in the refrigerant circulation amount control means 20.

そして、この吐出圧力検出手段２４から検出される圧縮機の吐出圧力を適正な所定の吐出圧力に制御すれば、効率の良い給湯加熱運転が可能となる。図３において、この適正な所定の吐出圧力である目標吐出圧力を記憶しているのが目標記憶手段１９である。 And if the discharge pressure of the compressor detected from this discharge pressure detection means 24 is controlled to an appropriate predetermined discharge pressure, an efficient hot water supply heating operation becomes possible. In FIG. 3, the target storage means 19 stores the target discharge pressure, which is an appropriate predetermined discharge pressure.

動作、作用について説明する。まず、冷媒回路で加熱することによって貯湯槽に湯を貯湯する沸き上げ運転について説明する。この場合、制御手段１６は、減圧装置３の弁開度を所定の起動弁開度に設定し、さらに、必要な加熱能力を得るために圧縮機１の所定の運転周波数を設定して、圧縮機１を起動する。そして、圧縮機１が前記所定の運転周波数に達した後、所定の条件が成り立てば、圧縮機１の吐出圧力を検出する吐出圧力検出手段２１からの信号で、前記吐出圧力を所定の吐出圧力（目標吐出圧力）になるように、減圧装置３の弁開度を制御することによって最適な冷媒循環量になるようにしている。なお、前記所定の条件としては、圧縮機１の起動後の運転時間が所定の時間に達するか、吐出圧力が安定するか、吐出圧力が所定の吐出圧力に達するかなどである。 The operation and action will be described. First, a boiling operation for storing hot water in a hot water tank by heating in a refrigerant circuit will be described. In this case, the control means 16 sets the valve opening of the decompression device 3 to a predetermined starting valve opening, and further sets a predetermined operating frequency of the compressor 1 to obtain a required heating capacity, The machine 1 is started. When the predetermined condition is satisfied after the compressor 1 reaches the predetermined operating frequency, the discharge pressure is determined by a signal from the discharge pressure detecting means 21 that detects the discharge pressure of the compressor 1. By controlling the valve opening degree of the decompression device 3 so as to be (target discharge pressure), the optimum refrigerant circulation amount is obtained. The predetermined condition includes whether the operation time after starting up the compressor 1 reaches a predetermined time, whether the discharge pressure is stabilized, whether the discharge pressure reaches a predetermined discharge pressure, or the like.

次に、給湯端末が開かれて、給水管から供給された市水を冷媒回路で加熱し給湯端末へと通水する給湯加熱運転について説明する。この場合についても、沸き上げ運転と同様の
吐出圧力の制御を行うことによって、最適な冷媒循環量になるようにする。 Next, a hot water supply heating operation in which the hot water supply terminal is opened and the city water supplied from the water supply pipe is heated by the refrigerant circuit and passed to the hot water supply terminal will be described. Also in this case, the optimum refrigerant circulation amount is obtained by controlling the discharge pressure in the same manner as in the boiling operation.

上記のように、応答が速い吐出圧力を制御対象にしているため、比較的運転時間が長い沸き上げ運転でも、比較的運転時間が短い給湯加熱運転でも、圧縮機１の吐出圧力を所定の吐出圧力（目標吐出圧力）になるように、減圧装置３の弁開度を制御する。このようにすれば、加熱運転の時間の長さに関係なく、最適な冷媒循環量が得られ、効率の良い運転ができる。 As described above, since the discharge pressure having a quick response is targeted for control, the discharge pressure of the compressor 1 can be controlled to a predetermined level even in a heating operation with a relatively long operation time or a hot water supply heating operation with a relatively short operation time. The valve opening degree of the decompression device 3 is controlled so as to be a pressure (target discharge pressure). In this way, an optimum refrigerant circulation amount can be obtained regardless of the length of time of the heating operation, and an efficient operation can be performed.

（実施の形態３）
図４は本発明の第３の実施の形態におけるヒートポンプ給湯機の構成図である。なお、本発明の第１の実施の形態で説明した図１と同じ構成部材には同一符号を用い説明を省略する。図１と異なる点は、冷媒の循環量の制御対象として、冷凍サイクルの状態を決める物理量から計算される圧縮機１の吸入冷媒の過熱度としたことである。つまり、冷媒循環量制御手段２０として，圧縮機１の吸入冷媒の過熱度を検出する過熱度検出手段２２と減圧装置３と制御装置１６とを用いたことである。第１の実施の形態と同様、冷媒循環量制御手段２０のなかに、圧縮機１を含んでも良い。さらに、過熱度検出手段２２の一例として、空気熱交換器４と圧縮機１の間の冷媒の温度を検出する吸入温度検出手段２３と空気熱交換器４で蒸発する冷媒の温度を検出する蒸発温度検出手段２４とを用いている。そして、過熱度は、吸入温度検出手段２３の検出温度と蒸発温度検出手段２４の検出温度との差で求まる。この過熱度を適正な所定の過熱度に制御すれば、効率の良い給湯加熱運転が可能となる。図４において、この適正な所定の過熱度である目標過熱度を記憶しているのが目標記憶手段１６である。 (Embodiment 3)
FIG. 4 is a configuration diagram of a heat pump water heater in the third embodiment of the present invention. In addition, the same code | symbol is used for the same component as FIG. 1 demonstrated in the 1st Embodiment of this invention, and description is abbreviate | omitted. The difference from FIG. 1 is that the degree of superheat of the suction refrigerant of the compressor 1 calculated from the physical quantity that determines the state of the refrigeration cycle is set as the control target of the refrigerant circulation amount. That is, as the refrigerant circulation amount control means 20, the superheat degree detection means 22 that detects the superheat degree of the refrigerant sucked in the compressor 1, the decompression device 3, and the control device 16 are used. Similarly to the first embodiment, the compressor 1 may be included in the refrigerant circulation amount control means 20. Furthermore, as an example of the superheat degree detection means 22, the suction temperature detection means 23 that detects the temperature of the refrigerant between the air heat exchanger 4 and the compressor 1 and the evaporation that detects the temperature of the refrigerant evaporated by the air heat exchanger 4. The temperature detecting means 24 is used. The degree of superheat is obtained from the difference between the temperature detected by the suction temperature detecting means 23 and the temperature detected by the evaporating temperature detecting means 24. If this superheat degree is controlled to an appropriate predetermined superheat degree, an efficient hot water supply heating operation becomes possible. In FIG. 4, the target storage means 16 stores the target superheat degree which is an appropriate predetermined superheat degree.

動作、作用について説明する。まず、冷媒回路で加熱することによって貯湯槽に湯を貯湯する沸き上げ運転について説明する。この場合、制御手段１６は、減圧装置３の弁開度を所定の起動弁開度に設定し、さらに、必要な加熱能力を得るために圧縮機１の所定の運転周波数を設定して、圧縮機１を起動する。そして、圧縮機１が前記所定の運転周波数に達した後、所定の条件が成り立てば、圧縮機１の吸入冷媒の過熱度を検出する過熱度検出手段２２からの信号で、前記吸入冷媒の過熱度を所定の過熱度（目標過熱度）になるように、減圧装置３の弁開度を制御することによって最適な冷媒循環量になるようにしている。なお、前記所定の条件としては、圧縮機１の起動後の運転時間が所定の時間に達するか、過熱度が安定するか、過熱度が所定の過熱度に達するかなどである。 The operation and action will be described. First, a boiling operation for storing hot water in a hot water tank by heating in a refrigerant circuit will be described. In this case, the control means 16 sets the valve opening of the decompression device 3 to a predetermined starting valve opening, and further sets a predetermined operating frequency of the compressor 1 to obtain a required heating capacity, The machine 1 is started. Then, after the compressor 1 reaches the predetermined operating frequency, if a predetermined condition is satisfied, the superheat of the suction refrigerant is detected by a signal from the superheat degree detection means 22 that detects the superheat degree of the suction refrigerant of the compressor 1. By controlling the valve opening degree of the pressure reducing device 3 so that the degree becomes a predetermined degree of superheat (target degree of superheat), an optimum refrigerant circulation amount is obtained. The predetermined condition includes whether the operation time after starting up the compressor 1 reaches a predetermined time, whether the degree of superheat is stable, whether the degree of superheat reaches a predetermined degree of superheat, and the like.

次に、給湯端末が開かれて、給水管から供給された市水を冷媒回路で加熱し給湯端末へと通水する給湯加熱運転について説明する。この場合についても、沸き上げ運転と同様の圧縮機１の吸入冷媒の過熱度の制御を行うことによって、最適な冷媒循環量になるようにする。 Next, a hot water supply heating operation in which the hot water supply terminal is opened and the city water supplied from the water supply pipe is heated by the refrigerant circuit and passed to the hot water supply terminal will be described. Also in this case, the optimum refrigerant circulation amount is obtained by controlling the degree of superheat of the refrigerant sucked in the compressor 1 as in the boiling operation.

上記のように、比較的応答が速い圧縮機１の吸入冷媒の過熱度を制御対象にしているため、比較的運転時間が長い沸き上げ運転でも、比較的運転時間が短い給湯加熱運転でも、圧縮機１の吸入冷媒の過熱度を所定の過熱度（目標過熱度）になるように、減圧装置３の弁開度を制御する。このようにすれば、加熱運転の時間の長さに関係なく、最適な冷媒循環量が得られ、効率の良い運転ができる。 As described above, since the degree of superheat of the refrigerant sucked by the compressor 1 that has a relatively fast response is controlled, it can be compressed even in a boiling operation with a relatively long operation time or a hot water heating operation with a relatively short operation time. The valve opening degree of the decompression device 3 is controlled so that the superheat degree of the refrigerant sucked in the machine 1 becomes a predetermined superheat degree (target superheat degree). In this way, an optimum refrigerant circulation amount can be obtained regardless of the length of time of the heating operation, and an efficient operation can be performed.

上記説明では、圧縮機１の吸入冷媒の過熱度を、吸入の冷媒温度と蒸発器での冷媒の蒸発温度とから求めたが、圧縮機１の吸入圧力を検出する吸入圧力検出手段（図示せず）を設け、圧縮機１の吸入圧力から求めた吸入の飽和温度と吸入温度とから求めても良い。 In the above description, the degree of superheat of the refrigerant sucked in the compressor 1 is obtained from the refrigerant temperature of the suction and the evaporation temperature of the refrigerant in the evaporator, but suction pressure detecting means (not shown) for detecting the suction pressure of the compressor 1 is shown. And the suction saturation temperature and the suction temperature obtained from the suction pressure of the compressor 1 may be obtained.

（実施の形態４）
図５は本発明の第４の実施の形態におけるヒートポンプ給湯機の構成図である。なお、
本発明の第１の実施の形態で説明した図１と同じ構成部材には同一符号を用い説明を省略する。図１と異なる点は、冷媒の循環量の制御対象として、冷凍サイクルの状態を決める物理量である圧縮機１の吐出温度と吐出圧力としたことである。つまり、冷媒循環量制御手段２０として，圧縮機１の吐出温度を検出する吐出温度検出手段１８と圧縮機１の吐出圧力を検出する吐出圧力検出手段２１と減圧装置３と制御装置１６とを用いたことである。第１の実施の形態と同様、冷媒循環量制御手段２０のなかに、圧縮機１を含んでも良い。 (Embodiment 4)
FIG. 5 is a configuration diagram of a heat pump water heater in the fourth embodiment of the present invention. In addition,
The same components as those in FIG. 1 described in the first embodiment of the present invention are denoted by the same reference numerals, and description thereof is omitted. The difference from FIG. 1 is that the discharge temperature and discharge pressure of the compressor 1, which are physical quantities that determine the state of the refrigeration cycle, are controlled as the circulation amount of the refrigerant. That is, as the refrigerant circulation amount control means 20, the discharge temperature detection means 18 that detects the discharge temperature of the compressor 1, the discharge pressure detection means 21 that detects the discharge pressure of the compressor 1, the decompression device 3, and the control device 16 are used. It was. Similarly to the first embodiment, the compressor 1 may be included in the refrigerant circulation amount control means 20.

そして、この吐出温度検出手段１８から検出される圧縮機１の吐出温度を適正な所定の吐出温度に制御するか、または、吐出圧力検出手段２１から検出される圧縮機の吐出圧力を適正な所定の吐出圧力に制御すれば、効率の良い加熱運転が可能となる。図５において、この適正な所定の吐出温度である目標吐出温度および適正な所定の吐出圧力である目標吐出圧力を記憶しているのが目標記憶手段１９である。 Then, the discharge temperature of the compressor 1 detected from the discharge temperature detection means 18 is controlled to an appropriate predetermined discharge temperature, or the compressor discharge pressure detected from the discharge pressure detection means 21 is set to an appropriate predetermined value. If the discharge pressure is controlled, an efficient heating operation is possible. In FIG. 5, the target storage means 19 stores the target discharge temperature, which is an appropriate predetermined discharge temperature, and the target discharge pressure, which is an appropriate predetermined discharge pressure.

次に、給湯端末が開かれて、給水管から供給された市水を冷媒回路で加熱し給湯端末へと通水する給湯加熱運転について説明する。この場合、制御手段１６は、減圧装置３の弁開度を所定の起動弁開度に設定し、さらに、必要な加熱能力を得るために圧縮機１の所定の運転周波数を設定して、圧縮機１を起動する。そして、圧縮機１が前記所定の運転周波数に達した後、所定の条件が成り立てば、圧縮機１の吐出圧力を検出する吐出圧力検出手段２１からの信号で、前記吐出圧力を所定の吐出圧力（目標吐出圧力）になるように、減圧装置３の弁開度を制御することによって最適な冷媒循環量になるようにしている。 Next, a hot water supply heating operation in which the hot water supply terminal is opened and the city water supplied from the water supply pipe is heated by the refrigerant circuit and passed to the hot water supply terminal will be described. In this case, the control means 16 sets the valve opening of the decompression device 3 to a predetermined starting valve opening, and further sets a predetermined operating frequency of the compressor 1 to obtain a required heating capacity, The machine 1 is started. When the predetermined condition is satisfied after the compressor 1 reaches the predetermined operating frequency, the discharge pressure is determined by a signal from the discharge pressure detecting means 21 that detects the discharge pressure of the compressor 1. By controlling the valve opening degree of the decompression device 3 so as to be (target discharge pressure), the optimum refrigerant circulation amount is obtained.

上記のように、比較的運転時間が長く、冷媒水熱交換器２の出口の水温度が高い沸き上げ運転時には圧縮機１の吐出温度を制御し、比較的運転時間が短く、冷媒水熱交換器２の出口の水温度が低い給湯加熱運転時には変化の応答の速い吐出圧力を制御するので、沸き上げ運転、給湯加熱運転それぞれに対して、最適な冷媒循環量になるため、効率の良い運転ができる。 As described above, during the boiling operation in which the operation time is relatively long and the water temperature at the outlet of the refrigerant water heat exchanger 2 is high, the discharge temperature of the compressor 1 is controlled, the operation time is relatively short, and the refrigerant water heat exchange is performed. Since the discharge pressure with a quick response to change is controlled during the hot water supply heating operation when the water temperature at the outlet of the water heater 2 is low, the refrigerant circulation amount is optimum for each of the boiling operation and the hot water supply heating operation. Can do.

（実施の形態５）
図６は本発明の第５の実施の形態におけるヒートポンプ給湯機の構成図である。なお、本発明の第１の実施の形態で説明した図１と同じ構成部材には同一符号を用い説明を省略する。図１と異なる点は、冷媒の循環量の制御対象として、冷凍サイクルの状態を決める物理量である圧縮機１の吐出温度と吸入冷媒の過熱度としたことである。つまり、冷媒循環量制御手段２０として，圧縮機１の吐出温度を検出する吐出温度検出手段１８と圧縮機１の吸入冷媒の過熱度を検出する過熱度検出手段２２と減圧装置３と制御装置１６とを用いたことである。第１の実施の形態と同様、冷媒循環量制御手段２０のなかに、圧縮機１を含んでも良い。さらに、第３の実施の形態で説明した図４と同様、過熱度検出手段２２の一例として、空気熱交換器４と圧縮機１の間の冷媒の温度を検出する吸入温度検出手段２３と空気熱交換器４で蒸発する冷媒の温度を検出する蒸発温度検出手段２４とを用いている。そして、この吐出温度検出手段１８から検出される圧縮機１の吐出温度を適正な所
定の吐出温度に制御するか、または、過熱度検出手段２２から検出される圧縮機の吸入冷媒の過熱度を適正な所定の過熱度に制御すれば、効率の良い加熱運転が可能となる。図６において、この適正な所定の吐出温度である目標吐出温度および適正な所定の過熱度である目標過熱度を記憶しているのが目標記憶手段１９である。 (Embodiment 5)
FIG. 6 is a configuration diagram of a heat pump water heater in the fifth embodiment of the present invention. In addition, the same code | symbol is used for the same component as FIG. 1 demonstrated in the 1st Embodiment of this invention, and description is abbreviate | omitted. A difference from FIG. 1 is that the discharge temperature of the compressor 1 and the superheat degree of the suction refrigerant, which are physical quantities that determine the state of the refrigeration cycle, are controlled as the circulation amount of the refrigerant. That is, as the refrigerant circulation amount control means 20, the discharge temperature detection means 18 that detects the discharge temperature of the compressor 1, the superheat degree detection means 22 that detects the superheat degree of the refrigerant sucked in the compressor 1, the decompression device 3, and the control device 16. And that. Similarly to the first embodiment, the compressor 1 may be included in the refrigerant circulation amount control means 20. Further, similarly to FIG. 4 described in the third embodiment, as an example of the superheat degree detection means 22, an intake temperature detection means 23 for detecting the temperature of the refrigerant between the air heat exchanger 4 and the compressor 1 and air The evaporating temperature detecting means 24 for detecting the temperature of the refrigerant evaporating in the heat exchanger 4 is used. Then, the discharge temperature of the compressor 1 detected from the discharge temperature detection means 18 is controlled to an appropriate predetermined discharge temperature, or the superheat degree of the refrigerant sucked in the compressor detected from the superheat degree detection means 22 is set. If the temperature is controlled to an appropriate predetermined degree of superheat, an efficient heating operation can be performed. In FIG. 6, the target storage means 19 stores the target discharge temperature, which is an appropriate predetermined discharge temperature, and the target superheat, which is an appropriate predetermined superheat.

動作、作用について説明する。まず、冷媒回路で加熱することによって貯湯槽に湯を貯湯する沸き上げ運転についは、図１で説明した本発明の第１の実施の形態と同様である。 The operation and action will be described. First, the boiling operation in which hot water is stored in a hot water tank by heating in a refrigerant circuit is the same as that of the first embodiment of the present invention described in FIG.

次に、給湯端末が開かれて、給水管から供給された市水を冷媒回路で加熱し給湯端末へと通水する給湯加熱運転について説明する。この場合、制御手段１６は、減圧装置３の弁開度を所定の起動弁開度に設定し、さらに、必要な加熱能力を得るために圧縮機１の所定の運転周波数を設定して、圧縮機１を起動する。そして、圧縮機１が前記所定の運転周波数に達した後、所定の条件が成り立てば、圧縮機１の吸入冷媒の過熱度を検出する過熱度検出手段２２からの信号で、前記吸入冷媒の過熱度を所定の過熱度（目標過熱度）になるように、減圧装置３の弁開度を制御することによって最適な冷媒循環量になるようにしている。なお、前記所定の条件としては、圧縮機１の起動後の運転時間が所定の時間に達するか、過熱度が安定するか、過熱度が所定の過熱度に達するかなどである。 Next, a hot water supply heating operation in which the hot water supply terminal is opened and the city water supplied from the water supply pipe is heated by the refrigerant circuit and passed to the hot water supply terminal will be described. In this case, the control means 16 sets the valve opening of the decompression device 3 to a predetermined starting valve opening, and further sets a predetermined operating frequency of the compressor 1 to obtain a required heating capacity, The machine 1 is started. Then, after the compressor 1 reaches the predetermined operating frequency, if a predetermined condition is satisfied, the superheat of the suction refrigerant is detected by a signal from the superheat degree detection means 22 that detects the superheat degree of the suction refrigerant of the compressor 1. By controlling the valve opening degree of the pressure reducing device 3 so that the degree becomes a predetermined degree of superheat (target degree of superheat), an optimum refrigerant circulation amount is obtained. The predetermined condition includes whether the operation time after starting up the compressor 1 reaches a predetermined time, whether the degree of superheat is stable, whether the degree of superheat reaches a predetermined degree of superheat, and the like.

上記のように、比較的運転時間が長く、冷媒水熱交換器２の出口の水温度が高い沸き上げ運転時には圧縮機１の吐出温度を制御し、比較的運転時間が短く、冷媒水熱交換器２の出口の水温度が低い給湯加熱運転時には変化の応答が比較的速い吸入冷媒の過熱度を制御するので、沸き上げ運転、給湯加熱運転それぞれに対して、最適な冷媒循環量になるため、効率の良い運転ができる。 As described above, during the boiling operation in which the operation time is relatively long and the water temperature at the outlet of the refrigerant water heat exchanger 2 is high, the discharge temperature of the compressor 1 is controlled, the operation time is relatively short, and the refrigerant water heat exchange is performed. Since the superheat degree of the suction refrigerant whose response to change is relatively fast is controlled during the hot water supply heating operation where the water temperature at the outlet of the water heater 2 is low, the refrigerant circulation amount is optimum for each of the boiling operation and the hot water supply heating operation. Efficient operation is possible.

本発明の第１の実施の形態におけるヒートポンプ給湯機の構成図The block diagram of the heat pump water heater in the 1st Embodiment of this invention 同、ヒートポンプ給湯機の運転時間に対する圧縮機の周波数と吐出圧力と吐出温度と減圧装置の弁開度との変化を示す図The figure which shows the change of the frequency of a compressor with respect to the operation time of a heat pump water heater, discharge pressure, discharge temperature, and the valve opening degree of a pressure reduction device. 本発明の第２の実施の形態におけるヒートポンプ給湯機の構成図The block diagram of the heat pump water heater in the 2nd Embodiment of this invention 本発明の第３の実施の形態におけるヒートポンプ給湯機の構成図The block diagram of the heat pump water heater in the 3rd Embodiment of this invention 本発明の第４の実施の形態におけるヒートポンプ給湯機の構成図The block diagram of the heat pump water heater in the 4th Embodiment of this invention 本発明の第５の実施の形態におけるヒートポンプ給湯機の構成図The block diagram of the heat pump water heater in the 5th Embodiment of this invention 従来例におけるの貯湯型ヒートポンプ給湯機の構成図Configuration diagram of a hot water storage type heat pump water heater in the conventional example 従来例におけるの瞬間湯沸かし型ヒートポンプ給湯機の構成図Configuration diagram of instant water heater type heat pump water heater in the conventional example 従来例におけるの貯湯槽を備えた瞬間湯沸かし型ヒートポンプ給湯機の構成図Configuration diagram of an instantaneous water heater type heat pump water heater equipped with a hot water storage tank in the conventional example 同、ヒートポンプ給湯機の運転時間に対する圧縮機の周波数と吐出圧力と吐出温度と減圧装置の弁開度との変化を示す図The figure which shows the change of the frequency of a compressor with respect to the operation time of a heat pump water heater, discharge pressure, discharge temperature, and the valve opening degree of a pressure reduction device.

Explanation of symbols

１圧縮機
２冷媒水熱交換器
３減圧装置
４空気熱交換器
５貯湯槽
１０給水管
１１給湯端末
１３水流路
１８吐出温度検出手段
２０冷媒循環量制御手段
２１吐出圧力検出手段
２２過熱度検出手段 DESCRIPTION OF SYMBOLS 1 Compressor 2 Refrigerant water heat exchanger 3 Pressure reducing device 4 Air heat exchanger 5 Hot water storage tank 10 Water supply pipe 11 Hot water supply terminal 13 Water flow path 18 Discharge temperature detection means 20 Refrigerant circulation amount control means 21 Discharge pressure detection means 22 Superheat degree detection means

Claims

A refrigerant circuit having a compressor, a refrigerant water heat exchanger as a radiator, a decompressor, an air heat exchanger as an evaporator, and a water flow path provided in the refrigerant water heat exchanger for exchanging heat with the radiator A water supply pipe for supplying city water, a hot water supply circuit connected so as to pass water from the water flow path to the hot water supply terminal, a hot water storage tank for storing hot water heated by the refrigerant circuit, and a discharge temperature of the compressor are detected. And a discharge temperature detecting means for performing boiling operation for storing hot water heated by the refrigerant water heat exchanger in the hot water storage tank, and passing hot water heated by the refrigerant water heat exchanger to a hot water supply terminal. A heat pump water heater having two operation operations of a hot water supply heating operation, wherein the temperature of the refrigerant discharged from the compressor is set lower in the hot water supply heating operation than in the boiling operation .

During heating operation, as the discharge temperature of the compressors becomes a predetermined discharge temperature, and controls the valve opening degree of the reduced pressure device, at the time of hot water heating operation, after circulation quantity control at the time of startup, the decompression device The heat pump water heater according to claim 1, wherein the valve opening is set to a predetermined valve opening.

3. The heat pump hot water supply according to claim 2, wherein the valve opening degree of the decompression device is controlled so that the discharge temperature of the compressor becomes a predetermined discharge temperature after a hot water supply heating operation is started and a predetermined time elapses. Machine.

A predetermined valve opening degree, the frequency of the compressor, outside air temperature, inlet temperature of the refrigerant-water heat exchanger, of the outlet temperature of the refrigerant-water heat exchanger, claims characterized in that it is determined based on the plurality of information Item 3. A heat pump water heater according to Item 2 .

The heat pump water heater according to any one of claims 1 to 4 , wherein the refrigerant used in the refrigerant circuit is carbon dioxide and is operated in a state exceeding a critical pressure on a high pressure side.