JP2008275239A - Heat pump hot water supply apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump hot water supply apparatus, preventing a turn-over phenomenon even in the state where foreign matter in a refrigeration cycle is still caught in a back pressure valve of a scroll compressor. <P>SOLUTION: This heat pump hot water supply apparatus includes: a discharge temperature detecting means 10B for detecting the temperature of a refrigerant discharged from the compressor 11; a target discharge temperature setting means for the temperature of the refrigerant discharged from the compressor 11; a hot water delivery temperature detecting means 20E for detecting the temperature of hot water after heat exchanged by a hot water supplying heat exchanger 12; an outside temperature detecting means 10D for detecting the outside air temperature; and a current value detection means for detecting a current value flowing through a heat pump hot water supply apparatus, wherein after a lapse of a fixed time after the compressor 11 is started, when the hot water delivery temperature is equal to or lower than a first predetermined temperature, the outside temperature is equal to or higher than a third predetermined temperature, and also the state where the current value is equal to or lower than a predetermined value α continues for a fixed time, the target discharge temperature preset by the target discharge temperature setting means is raised by a fourth predetermined temperature. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a heat pump type hot water supply apparatus, and more particularly to control for preventing overturning of a compressor.

  Conventionally, a heat pump hot water supply apparatus using a heat pump cycle having a variable capacity compressor has been proposed (see, for example, Patent Document 1). FIG. 3 is a cross-sectional view of a scroll compressor used as a compressor of a conventional heat pump type hot water supply apparatus. In FIG. 3, the fixed scroll 101 and the orbiting scroll 102 are meshed to form a compression chamber 103 therebetween, and the orbiting scroll 102 is revolved along a circular path under the rotation restraint by the rotation restraining mechanism 104. When the compression chamber 103 moves while changing its volume, the refrigerant is sucked, compressed, and discharged.

  Between the orbiting scroll 102 and the fixing member 105 that backs up the back side of the orbiting scroll 102, a high pressure portion 106 that applies high pressure by lubricating oil is provided at the center of the back surface of the orbiting scroll 102. A back pressure chamber 108 that is partitioned by a seal ring 107 and applies a predetermined pressure (back pressure) lower than that of the high pressure portion 106 is provided on the outer peripheral portion of the back surface, and the orbiting scroll 102 is fixed to the fixed scroll component by these high pressure and back pressure. By pressing against 101, the rollover phenomenon that the orbiting scroll 102 separates from the fixed scroll 101 does not occur (for example, see Patent Document 2).

  4 (a) and 4 (b) are enlarged views of the main part of the compression chamber 103 formed by the fixed scroll 101 and the orbiting scroll 102 of FIG. 3, and FIG. 4 (a) is not less than the lower limit value of the usable compression ratio. Fig. 4 (b) is an enlarged view of the main part when operated at less than the lower limit value of the usable compression ratio. 4A and 4B, the compression chamber 103 is formed by the balance between the compression chamber pressure and the back pressure of the scroll compressor. During normal operation, the discharge pressure (absolute pressure) / suction pressure (absolute pressure) is formed. = Operating within the range of compression ratios where the compression ratio can be used, but when the operation is performed in a state where the compression ratio is smaller than the lower limit value of the usable compression ratio and the back pressure becomes small, the orbiting scroll 102 is fixed. A rollover phenomenon that leaves the scroll 101 occurs.

FIG. 5 is an enlarged view of the main part of the back pressure valve 109 of FIGS. 4 (a) and 4 (b). Since the spring pressure of the back pressure valve 109 is adjusted, the refrigerant normally passes through the path indicated by the arrow. Flows from the back pressure chamber 108 into the compression chamber 103, and the balance between the compression chamber pressure and the back pressure is maintained. At this time, the back pressure valve 109 moves up and down to change the amount of refrigerant flowing in from the opening 110, and the back pressure chamber 108 and the compression chamber 103 have a back pressure so that the pressure difference becomes a predetermined pressure difference. The pressure valve 109 moves up and down.
JP 2003-247759 A Japanese Patent Laid-Open No. 2002-266776

However, when a foreign object is caught in the inlet portion of the back pressure valve as in the prior art, the back pressure valve does not operate normally, and a rollover phenomenon is likely to occur. That is, the overturning phenomenon occurs even when the compression ratio is not less than the lower limit of the normally usable compression ratio. When the capsizing phenomenon occurs, the temperature of the refrigerant discharged from the scroll compressor is significantly lower than the target discharge temperature, so the expansion valve opening is controlled to match the target discharge temperature, but the capsizing phenomenon occurs. If the opening is not smaller than the expansion valve opening degree, the overturning does not return, so that the discharge temperature greatly overshoots after the overturning is restored. For this reason, if the expansion valve opening is widened again to adjust the discharge temperature to the target discharge temperature, foreign matter is caught in the back pressure valve, so the back pressure valve does not operate normally, and the compression chamber and back Since the pressure balance with the pressure chamber cannot be maintained normally, the capsizing phenomenon occurs again in the vicinity of the pre-rotation capping phenomenon, resulting in a decrease in hot water supply capacity, noise and vibration due to the capping phenomenon. It had the problem of end. Even if foreign matter or the like does not bite, the same problem occurs when the back pressure valve portion has burrs.

  The present invention solves the above-mentioned conventional problems, and provides a heat pump hot water supply apparatus capable of preventing the overturning phenomenon even when foreign matter in the refrigeration cycle is sandwiched between the back pressure valves of the scroll compressor. The purpose is to do.

  In order to solve the above-mentioned conventional problems, a heat pump hot water supply apparatus of the present invention is a heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe. And a discharge temperature detecting means for detecting the temperature of the refrigerant discharged from the scroll compressor, a target discharge temperature setting means for setting the temperature of the refrigerant discharged from the scroll compressor, and the heat exchanger for hot water supply. The scroll compression comprising: a hot water temperature detecting means for detecting the temperature of hot water after replacement; an outside air temperature detecting means for detecting an outside air temperature; and a current value detecting means for detecting a current value flowing through the heat pump water heater. The hot water temperature detected by the hot water temperature detecting means is equal to or lower than a first predetermined temperature after the elapse of a certain time from the start of the machine, and the discharge temperature. The discharge temperature detected by the outlet means is equal to or lower than the second predetermined temperature, the outside air temperature detected by the outside air temperature detecting means is equal to or higher than the third predetermined temperature, and the current value detected by the current value detecting means Is maintained for a predetermined time, the target discharge temperature set by the target discharge temperature setting means is raised to a fourth predetermined temperature.

  As a result, when the overturning phenomenon is detected, the target discharge temperature is further increased by the fourth predetermined temperature, so that the compression ratio can be ensured because the high pressure side rises, and foreign matter is caught in the back pressure valve 109. However, since the discharge pressure increases (that is, the back pressure increases), the back pressure valve 109 is raised to the extent that foreign matter does not affect the balance between the back pressure and the pressure in the compression chamber, and an appropriate back pressure can be secured. In addition, the overturning phenomenon due to the biting of foreign matter can be prevented.

  Further, the heat pump hot water supply apparatus of the present invention is a heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water supply heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe, from the scroll compressor Discharge temperature detection means for detecting the temperature of the discharged refrigerant, target discharge temperature setting means for the temperature of the refrigerant discharged from the scroll compressor, and the temperature of hot water after heat exchange by the hot water supply heat exchanger Hot water temperature detecting means for detecting the outside air temperature detecting means for detecting the outside air temperature, current value detecting means for detecting the current value flowing through the heat pump hot water supply device, a blower for sending air to the evaporator, and A blower air volume variable means for changing the air volume, and after the elapse of a certain time from the start of the scroll compressor, the tapping temperature detecting means detects the air temperature. The discharged hot water temperature is not more than a first predetermined temperature, the discharge temperature detected by the discharge temperature detecting means is not more than a second predetermined temperature, and the outside air temperature detected by the outside air temperature detecting means is a third temperature. When the state where the current value detected by the current value detecting means is equal to or higher than a predetermined temperature and the current value detected by the current value detecting means is equal to or less than a predetermined value α continues for a certain period of time, the air volume of the blower is decreased by a predetermined air volume by the blower air volume varying means It is.

As a result, when a rollover phenomenon is detected, the low-pressure side is lowered in order to further reduce the blower air volume by a predetermined air volume. That is, when the pressure in the compression chamber decreases, even when foreign matter is caught in the back pressure valve 109 (that is, when the back pressure is difficult to increase), the pressure balance between the back pressure chamber and the compression chamber is maintained, and the capsizing is caused by the foreign matter being caught. The phenomenon can be prevented.

  Further, the heat pump hot water supply apparatus of the present invention is a heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water supply heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe, from the scroll compressor Discharge temperature detection means for detecting the temperature of the discharged refrigerant, target discharge temperature setting means for the temperature of the refrigerant discharged from the scroll compressor, and the temperature of hot water after heat exchange by the hot water supply heat exchanger Hot water temperature detecting means for detecting the outside air temperature detecting means for detecting the outside air temperature, current value detecting means for detecting the current value flowing through the heat pump hot water supply device, a blower for sending air to the evaporator, and A blower air volume variable means for changing the air volume, and after the elapse of a certain time from the start of the scroll compressor, the tapping temperature detecting means detects the air temperature. The discharged hot water temperature is not more than a first predetermined temperature, the discharge temperature detected by the discharge temperature detecting means is not more than a second predetermined temperature, and the outside air temperature detected by the outside air temperature detecting means is a third temperature. When the state where the current value detected by the current value detecting means is equal to or higher than a predetermined temperature and the current value detected by the current value detecting means is equal to or less than a predetermined value α continues for a certain time, the target discharge temperature set by the target discharge temperature setting means is increased by a fourth predetermined temperature. And the air volume of the air blower is lowered by a predetermined air volume by the air flow rate varying means.

  As a result, when the capsize phenomenon is detected, the target discharge temperature is further increased by the fourth predetermined temperature, so that the high pressure side is increased, and the low pressure side is decreased to further reduce the blower air volume by the predetermined air volume, thereby ensuring the compression ratio. Can do. That is, when the high pressure is increased, the back pressure is increased, and the back pressure valve 109 is raised to the extent that foreign matter does not affect the pressure balance between the back pressure chamber and the compression chamber, so that an appropriate back pressure can be secured and the low pressure is reduced. Lowering the pressure in the compression chamber reduces the pressure balance between the back pressure chamber and the compression chamber even when foreign matter is caught in the back pressure valve 109, and prevents overturning due to foreign matter biting. can do. The fourth predetermined temperature can be set lower as much as it is easier to obtain a compression ratio than when the air volume of the blower is not reduced, and it becomes easy to prevent an abnormal increase in high pressure.

  The heat pump hot water supply apparatus of the present invention can provide a heat pump hot water supply apparatus that can prevent the overturning phenomenon even when the foreign matter in the refrigeration cycle is sandwiched between the back pressure valves of the scroll compressor.

  A heat pump hot water supply apparatus according to a first aspect of the present invention is a heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water supply heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe, from the scroll compressor Discharge temperature detection means for detecting the temperature of the discharged refrigerant, target discharge temperature setting means for the temperature of the refrigerant discharged from the scroll compressor, and the temperature of hot water after heat exchange by the hot water supply heat exchanger A hot water temperature detecting means for detecting the outside air temperature, an outside air temperature detecting means for detecting the outside air temperature, and a current value detecting means for detecting a current value flowing through the heat pump hot water supply device, and a predetermined time after the scroll compressor is started After elapses, the discharge temperature detected by the discharge temperature detection means is not more than a first predetermined temperature and the discharge temperature detection means detects the discharge temperature detected by the discharge temperature detection means. The temperature is not more than a second predetermined temperature, the outside temperature detected by the outside temperature detecting means is not less than a third predetermined temperature, and the current value detected by the current value detecting means is not more than a predetermined value α. When the rollover phenomenon is detected by raising the target discharge temperature set by the target discharge temperature setting means to the fourth predetermined temperature and detecting the rollover phenomenon, the target discharge temperature is further increased by the fourth predetermined temperature. Since the high pressure side rises, the compression ratio can be secured, and even if foreign matter is caught in the back pressure valve 109, the discharge pressure rises (that is, the back pressure rises). As a result, the back pressure valve 109 is raised to the extent that the foreign matter is not affected, and the overturning phenomenon due to the biting of the foreign matter can be prevented.

  A heat pump hot water supply apparatus according to a second invention is a heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water supply heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe, from the scroll compressor Discharge temperature detection means for detecting the temperature of the discharged refrigerant, target discharge temperature setting means for the temperature of the refrigerant discharged from the scroll compressor, and the temperature of hot water after heat exchange by the hot water supply heat exchanger Hot water temperature detecting means for detecting the outside air temperature detecting means for detecting the outside air temperature, current value detecting means for detecting the current value flowing through the heat pump hot water supply device, a blower for sending air to the evaporator, and A blower air volume variable means for changing the air volume, and is detected by the tapping temperature detecting means after a lapse of a certain time from the start of the scroll compressor. The discharged hot water temperature is not more than a first predetermined temperature, the discharge temperature detected by the discharge temperature detecting means is not more than a second predetermined temperature, and the outside air temperature detected by the outside air temperature detecting means is a third temperature. When the state where the current value detected by the current value detecting means is equal to or higher than a predetermined temperature and the current value detected by the current value detecting means is a predetermined value α or less continues for a certain period of time, the air flow of the blower is reduced by a predetermined air volume by the fan air volume varying means, thereby When detected, the low-pressure side is lowered in order to further reduce the blower air volume by a predetermined air volume. That is, when the pressure in the compression chamber decreases, even when foreign matter is caught in the back pressure valve 109 (that is, when the back pressure is difficult to increase), the pressure balance between the back pressure chamber and the compression chamber is maintained, and the capsizing is caused by the foreign matter being caught. The phenomenon can be prevented.

  A heat pump hot water supply apparatus according to a third aspect of the present invention is a heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water supply heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner through a refrigerant pipe, from the scroll compressor Discharge temperature detection means for detecting the temperature of the discharged refrigerant, target discharge temperature setting means for the temperature of the refrigerant discharged from the scroll compressor, and the temperature of hot water after heat exchange by the hot water supply heat exchanger Hot water temperature detecting means for detecting the outside air temperature detecting means for detecting the outside air temperature, current value detecting means for detecting the current value flowing through the heat pump hot water supply device, a blower for sending air to the evaporator, and A blower air volume variable means for changing the air volume, and is detected by the tapping temperature detecting means after a lapse of a certain time from the start of the scroll compressor. The discharged hot water temperature is not more than a first predetermined temperature, the discharge temperature detected by the discharge temperature detecting means is not more than a second predetermined temperature, and the outside air temperature detected by the outside air temperature detecting means is a third temperature. When the state where the current value detected by the current value detecting means is equal to or higher than a predetermined temperature and the current value detected by the current value detecting means is equal to or less than a predetermined value α continues for a certain time, the target discharge temperature set by the target discharge temperature setting means is increased by a fourth predetermined temperature. When the capsizing phenomenon is detected by lowering the air volume of the blower by the blower air volume varying means, the target discharge temperature is further raised by the fourth predetermined temperature, so that the high pressure side is increased and the blower air volume is further increased. Since the air flow is lowered by a predetermined amount, the low pressure side is lowered, and the compression ratio can be ensured. That is, when the high pressure is increased, the back pressure is increased, and the back pressure valve 109 is raised to the extent that foreign matter does not affect the pressure balance between the back pressure chamber and the compression chamber, so that an appropriate back pressure can be secured and the low pressure is reduced. Lowering the pressure in the compression chamber reduces the pressure balance between the back pressure chamber and the compression chamber even when foreign matter is caught in the back pressure valve 109, and prevents overturning due to foreign matter biting. can do. The fourth predetermined temperature can be set lower as much as it is easier to obtain a compression ratio than when the air volume of the blower is not reduced, and it becomes easy to prevent an abnormal increase in high pressure.

  A heat pump hot-water supply apparatus according to a fourth aspect of the invention includes a target hot-water supply temperature setting means for setting a target hot-water supply temperature of hot water after heat exchange in the hot-water supply heat exchanger, in the first to third aspects of the invention. 1 is obtained by subtracting the fifth predetermined temperature from the target hot water temperature set by the target hot water temperature setting means, thereby associating the target hot water temperature with the actual hot water temperature. The first predetermined temperature can be set according to the tapping temperature, and erroneous determination of the overturning phenomenon of the compressor can be prevented.

In the heat pump hot water supply apparatus of the fifth invention, particularly in the first to fourth inventions, when the outside air temperature detected by the outside air temperature detecting means is equal to or lower than an eighth predetermined temperature, the target discharge temperature setting means The outside air temperature is reduced by releasing the set target discharge temperature by the fourth predetermined temperature and / or releasing the air volume of the blower by the blower air volume varying means. In the case of temperature, since the low pressure side is low, the compression ratio can be secured, so operate so as to reach the target discharge temperature set by the target discharge temperature setting means, and stop reducing the air volume of the blower by the predetermined air volume Therefore, efficient operation can be performed.

  The heat pump hot water supply apparatus according to a sixth aspect of the invention includes the boiling number storage means for storing the number of times of boiling, particularly in the first to fifth aspects, and the number of times of boiling stored by the boiling number storage means is a predetermined number of times. When it becomes above, canceling | releasing raising the target discharge temperature set by the said target discharge temperature setting means only to 4th predetermined temperature, and / or the air volume of the said air blower by the air blower air volume variable means is made into predetermined air volume By releasing the lowering, the number of times of boiling can be repeated several times, so foreign matter can be removed at some point in time. A boiling operation can be performed and an efficient operation can be performed.

  The heat pump hot-water supply apparatus according to the seventh aspect of the invention includes the operation time storage means for storing the operation time, particularly in the first to sixth inventions, and the operation time stored by the operation time storage means becomes a predetermined time or more. The release of raising the target discharge temperature set by the target discharge temperature setting means by a fourth predetermined temperature and / or releasing the air flow of the blower by the blower air volume varying means is released. If the boiling operation is carried out for a long time, foreign matter may be removed at any moment, so by performing the boiling operation for a long time, the restriction is once released and the normal boiling operation is performed. Can be performed efficiently.

  The heat pump hot water supply apparatus according to an eighth aspect of the invention includes a target discharge temperature setting means for setting a target value of a refrigerant temperature discharged from the scroll compressor, particularly in the first to seventh aspects of the invention, and a second predetermined temperature, By subtracting the sixth predetermined temperature from the target discharge temperature set by the target discharge temperature setting means, the discharge temperature and the target discharge temperature can be associated with each other. It can be provided according to the target discharge temperature, and the rollover phenomenon can be reliably prevented without erroneous detection.

  A heat pump hot water supply apparatus according to a ninth aspect of the invention includes a target hot water temperature setting means for setting a target hot water temperature of hot water after heat exchange in the hot water supply heat exchanger in the first to eighth inventions, 2 is obtained by adding the seventh predetermined temperature to the target hot water temperature set by the target hot water temperature setting means, so that the discharge temperature and the target hot water temperature can be associated. The threshold value for judging the phenomenon can be provided according to the target hot water temperature, and the capsizing phenomenon can be reliably prevented without erroneous detection.

  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.

(Embodiment 1)
1 is a circuit configuration diagram of a heat pump water heater in Embodiment 1 of the present invention. First, based on FIG. 1, the structure of the heat pump hot-water supply apparatus by a present Example is demonstrated. In FIG. 1, the heat pump circuit 10 according to the present embodiment uses carbon dioxide as a refrigerant and operates in a state where the critical pressure is exceeded on the high pressure side (the discharge pressure side of the compressor). Of course, carbon dioxide is adopted as the refrigerant in this embodiment, but there is no problem even if the heat pump circuit is composed of other refrigerants as long as the high pressure side exceeds the critical pressure. In the first embodiment, the heat pump hot water supply apparatus will be described as a separate type heat pump hot water supply apparatus including a tank unit 60 and a heat pump unit 61. Of course, the tank unit and the heat pump unit are integrally configured. An integrated heat pump hot water supply apparatus may be used.

  The heat pump circuit 10 is configured by connecting a scroll compressor 11, a hot water supply heat exchanger 12, a main expansion valve 13A, a capillary tube 13B, and an evaporator 14 in this order by piping. A blower 15 that sends air to the evaporator 14 is installed on the leeward side of the evaporator 14. Further, since the structure of the scroll compressor 11 is the same as that of the conventional structure, the same reference numerals as those of the conventional example are given and detailed description is omitted.

  The heat pump circuit 10 includes a temperature sensor 10A for detecting the temperature of the scroll compressor 11, a temperature sensor (discharge temperature detecting means) 10B for detecting a discharge temperature from the scroll compressor 11, and a discharge refrigerant pressure from the scroll compressor 11. A pressure sensor 10C for detecting, a temperature sensor (outside air temperature detecting means) 10D for detecting the intake air of the evaporator 14, and a temperature sensor 10E for detecting the evaporator temperature of the evaporator 14 are provided. Here, the temperature sensor 10 </ b> A detects cold start, and the pressure sensor 10 </ b> C detects abnormality of the scroll compressor 11 or the heat pump circuit 10.

  Next, a hot water storage circuit of the heat pump hot water supply apparatus according to this embodiment will be described. A bottom pipe 21 of the hot water storage tank 20 is connected to a water supply pipe 32 such as a water pipe via a pressure reducing valve 31. The bottom piping 22 of the hot water storage tank 20 is connected to the inflow side of the water piping 12 </ b> A of the hot water supply heat exchanger 12 through the circulation pump 23. The upper circulation pipe 24 of the hot water storage tank 20 is connected to the outflow side of the water pipe 12A. The hot water storage tank 20 according to the present embodiment is a stacked hot water storage tank, and is configured so that stirring in the tank is prevented and high temperature water is accumulated at the top and low temperature water is accumulated at the bottom.

  On the other hand, the upper hot water supply pipe 33 of the hot water storage tank 20 is connected to the mixing valve 34. Further, a water discharge pipe 35 branched from the bottom pipe 21 of the hot water storage tank 20 is connected to the mixing valve 34. The outlet circuit on the outflow side of the mixing valve 34 is connected to a faucet 36 for hot water supply such as a kitchen or a washroom. This tapping circuit is provided with a flow sensor 30A for detecting the tapping amount and a temperature sensor 30B for detecting tapping temperature.

  The hot water storage tank 20 is provided with a plurality of temperature sensors 20A, 20B, 20C for detecting the amount of hot water in the hot water storage tank 20. In addition, a temperature sensor 20 </ b> D that detects the incoming water temperature derived from the bottom pipe 22 of the hot water storage tank 20 is provided in the inflow side pipe of the water pipe 12 </ b> A. The upper circulation pipe 24 is provided with a temperature sensor (hot water temperature detecting means) 20E for detecting the hot water temperature derived from the water pipe 12A.

  Hereinafter, the hot water storage operation of the heat pump hot water supply apparatus according to the present embodiment will be described. When the time reaches a predetermined time or the temperature sensors 20A, 20B, and 20C in the hot water storage tank 20 detect that the amount of hot water in the hot water storage tank 20 has become less than a predetermined amount, the heat pump circuit 10 is operated to store hot water. Start driving.

  In the heat pump circuit 10, the refrigerant compressed by the scroll compressor 11 radiates heat by the hot water supply heat exchanger 12, is depressurized by the main expansion valve 13 </ b> A and the capillary tube 13 </ b> B, and then is sent by the blower 15 by the evaporator 14. Heat is absorbed from the coming air and is sucked into the scroll compressor 11 in a gas state.

  On the other hand, by the operation of the circulation pump 23, the water in the hot water storage tank 20 is guided to the water pipe 12A through the bottom pipe 22, and the hot water heated by the water pipe 12A passes through the upper circulation pipe 24. It is returned to the hot water storage tank 20.

  The capacity control in the scroll compressor 11 and the opening control in the expansion valve 13 are controlled so that the discharge temperature detected by the temperature sensor 10B maintains a preset temperature.

  Further, the present embodiment is provided with a microcomputer 50 which is a control means for controlling each device constituting the heat pump unit. The target discharge temperature setting means for setting the target discharge temperature of the compressor, and the blower air volume variable. Means and target hot water temperature setting means. Moreover, the current value detection means (not shown) which detects the current value of the heat pump unit of the heat pump water heater is provided.

  Next, a compressor overturn detection method and an operation after the compressor overturn detection in the heat pump hot water supply apparatus according to this embodiment will be described with reference to FIG. FIG. 2 is a flowchart showing a method for detecting the overturning phenomenon and a method for controlling the refrigeration cycle in the present embodiment.

  First, in STEP 1, at the same time when the power is turned on, the microcomputer 50 sets a “rollover detection flag” indicating whether the rollover has occurred, and proceeds to STEP 2. If the “overturn detection flag” is “0”, it is a variable for determining that it is not overturned, and if the “overturn detection flag” is “1”, it is determined that it is overturned.

  In STEP2, it is determined whether or not the boiling operation has been started. If the boiling operation has not been started, STEP2 is repeated until the operation is started, and if the boiling operation is started, the number of times of boiling is counted. Is increased once and the process proceeds to STEP3.

  In STEP 3, the hot water temperature Ts, the outside air temperature Tg, and the current value I are detected, and the process proceeds to STEP 4.

  In STEP 4, it is determined whether or not a predetermined time has elapsed since the start of the compressor. If the predetermined time has elapsed, the process proceeds to STEP 5, and if the predetermined time has not elapsed, the process proceeds to STEP 6.

  In STEP 5, it is determined whether or not the compression ratio is not obtained even though a predetermined time has elapsed since the start of the compressor, and whether or not it is overturned. In the present embodiment, the determination is made based on the temperature of the hot water discharged from the hot water supply heat exchanger, the discharge temperature of the refrigerant discharged from the compressor, the outside air temperature, and the current value in the heat pump unit. Specifically, the hot water temperature Ts is lower than the first predetermined temperature T1, the discharge temperature Tt is lower than the second predetermined temperature T2, the outside air temperature Tg is higher than the third predetermined temperature T3, and When the current value I is smaller than the predetermined current value α, it is determined that the scroll compressor 11 does not exhibit the desired capacity, and it is determined that the rollover state is present. If it is determined that the rollover state is set, “1” is set in the “rollover detection flag” to indicate the rollover state, and the process proceeds to STEP 6.

  In this embodiment, the tapping temperature Ts is compared with the first predetermined temperature T1, but instead of the first predetermined temperature T1, the fixed temperature is fixed from the target temperature set by the target tapping temperature setting means. A value obtained by subtracting the fifth predetermined temperature T5 as a value may be used. In that case, since the tapping temperature Ts and the target tapping temperature can be associated with each other, a threshold value for judging the capsizing phenomenon can be set according to the target tapping temperature, and the capsizing phenomenon is reliably prevented without erroneous detection. can do.

Further, the discharge temperature Tt is compared with the second predetermined temperature T2, but instead of the second predetermined temperature T2, a sixth value which is a fixed value from the target discharge temperature set by the target discharge temperature setting means. A value obtained by subtracting the predetermined temperature T6 may be used. In this case, since the discharge temperature Tt and the target discharge temperature can be associated, a threshold value for judging the overturning phenomenon can be provided according to the target discharge temperature, and the overturning phenomenon can be reliably prevented without erroneous detection. can do.

  Instead of the second predetermined temperature T2, a value obtained by adding a seventh predetermined temperature T7 which is a fixed value to the target hot water temperature set by the target hot water temperature setting means may be used. In that case, since the discharge temperature Tt and the target hot water temperature can be correlated, a threshold value for judging the capsizing phenomenon can be set according to the target hot water temperature, and the capsizing phenomenon is reliably prevented without erroneous detection. can do.

  The first predetermined temperature T1 may be set for each target hot water temperature of hot water discharged from the hot water supply heat exchanger set by the target hot water temperature setting means.

  In STEP 6, it is determined whether the outside air temperature Tg is lower than the eighth predetermined temperature T8 or whether the count of the number of times of boiling is equal to or greater than the predetermined number of times of boiling. Here, by determining whether or not the outside air temperature Tg is lower than the eighth predetermined temperature T8, the low pressure side is lowered under a low outside air temperature condition, so that the compression ratio can be ensured, so that there is little risk of overturning again. In addition, by determining whether or not the count of the number of times of boiling is equal to or greater than the predetermined number of times of boiling, the foreign matter biting into the back pressure valve 109 of the scroll compressor 11 while the boiling operation is repeated is determined. There is a case where it can be taken with some time, so in that case there is little risk of capsizing again. Therefore, it is determined whether the outside air temperature Tg is lower than the eighth predetermined temperature T8 or the number of times of boiling is equal to or higher than the predetermined number of times of boiling. If applicable, the “overturn detection flag” is set to “0”. ”And proceed to STEP 7 and simultaneously clear the count of the number of times of boiling. On the other hand, if it does not correspond, it progresses to STEP7 as it is. In the present embodiment, it is determined whether or not the number of times of boiling is equal to or greater than the predetermined number of times. However, the same effect can be obtained by determining whether or not the operation time is equal to or greater than the predetermined operation time.

  In STEP 7, it is determined whether or not the current “overturn detection flag” is “1”. If the “overturn detection flag” is “1”, the process proceeds to STEP 8, and if the “overturn detection flag” is “0”. If so, proceed to STEP9.

  In STEP 8, since the “overturn detection flag” is set to “1”, the target discharge temperature is increased from the normal target discharge temperature to the fourth predetermined temperature T4, and the blower air volume is also decreased from the normal blower air volume by the predetermined air volume. Then go to STEP10.

  That is, if the main expansion valve 13A is controlled as it is after returning from the overturning phenomenon, the overturning phenomenon is likely to occur again. Therefore, if the target discharge temperature is set higher than the normal target discharge temperature, scroll compression is performed accordingly. Since the refrigerant discharged from the machine 11 also moves to the high pressure side, the back pressure rises, and even if foreign matter is caught in the back pressure valve 109 in an attempt to balance the pressure between the back pressure chamber and the compression chamber, it has an effect on it. Since the back pressure valve 109 is raised to the extent that there is no air pressure and an appropriate back pressure can be secured, the pressure balance between the compression chamber and the back pressure chamber can be maintained, and the overturning phenomenon can be prevented.

  In addition, by setting the blower air volume lower than the normal blower air volume, the low pressure side can be lowered and the pressure in the compression chamber is reduced. Therefore, even if foreign matter is caught in the back pressure valve 109, the compression chamber and the back air flow are reduced. The pressure balance with the pressure chamber can be maintained, and the overturning phenomenon can be prevented.

  In this embodiment, the target discharge temperature and the blower air volume are changed in STEP 8, but the present invention is not limited to this, and even if only one of them is changed, the capsizing phenomenon is prevented. It has the effect to do.

On the other hand, in STEP 9, since there is little possibility that the overturning phenomenon will occur again, the target discharge temperature and the air flow rate of the blower are operated at the normally set values, and the process proceeds to STEP 10.

  In STEP10, it is determined whether or not the operation is stopped. If the operation is not stopped, the process returns to STEP3. If the operation is stopped, the process returns to STEP2.

  As described above, when the overturning phenomenon occurs, the back pressure valve has a foreign object by increasing the target discharge temperature of the refrigerant discharged from the compressor in order to increase the high pressure side, or by reducing the blower air volume to decrease the low pressure side. Even if it is bitten, the back pressure is raised and the back pressure valve is raised to the extent that it is not affected by foreign matter, and the appropriate back pressure is secured or the pressure in the compression chamber is controlled to reduce the overturning phenomenon. It is possible to provide a stable heat pump water heater that does not occur again.

  As described above, the present invention can be applied not only to a heat pump hot water supply device that discharges water from a tank to a hot water supply port, but also to a heat pump hot water supply device that discharges hot water directly from a hot water supply heat exchanger.

The block diagram of the heat pump hot-water supply apparatus in Embodiment 1 of this invention Control flowchart in the first embodiment Sectional view of a conventional scroll compressor (A) Main part sectional view of conventional scroll compressor (during operation at or above lower limit of usable compression ratio) (b) Main part sectional view of conventional scroll compressor (lower than lower limit of usable compression ratio) Driving) Enlarged view of the main parts of a conventional scroll compressor

Explanation of symbols

10 heat pump circuit 10B temperature sensor (discharge temperature detection means)
10D temperature sensor (outside temperature detection means)
DESCRIPTION OF SYMBOLS 11 Scroll compressor 12 Heat exchanger for hot water supply 13A Main expansion valve 14 Evaporator 15 Blower 20E Temperature sensor (Tapping temperature detection means)

Claims (9)

A heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water supply heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe, and detects discharge temperature of refrigerant discharged from the scroll compressor A temperature detection means, a target discharge temperature setting means for the temperature of the refrigerant discharged from the scroll compressor, a hot water temperature detection means for detecting the temperature of hot water after heat exchange in the hot water supply heat exchanger, and outside air An outside air temperature detecting means for detecting the temperature and a current value detecting means for detecting a current value flowing through the heat pump hot water supply device, and detected by the tapping temperature detecting means after a lapse of a certain time from the start of the scroll compressor. The discharged hot water temperature is not more than a first predetermined temperature, and the discharge temperature detected by the discharge temperature detecting means is not more than a second predetermined temperature, and the When the outside air temperature detected by the air temperature detecting means is not less than a third predetermined temperature and the current value detected by the current value detecting means is not more than the predetermined value α for a certain period of time, the target discharge temperature setting means A heat pump hot water supply apparatus, wherein the target discharge temperature set by the step is raised to a fourth predetermined temperature. A heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water supply heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe, and detects discharge temperature of refrigerant discharged from the scroll compressor A temperature detection means, a target discharge temperature setting means for the temperature of the refrigerant discharged from the scroll compressor, a hot water temperature detection means for detecting the temperature of hot water after heat exchange in the hot water supply heat exchanger, and outside air Outside air temperature detecting means for detecting temperature, current value detecting means for detecting a current value flowing through the heat pump hot water supply device, a blower for sending air to the evaporator, and a blower air volume variable means for changing the air volume of the blower Provided, and after a predetermined time has elapsed since the scroll compressor was started, the tapping temperature detected by the tapping temperature detecting means is not more than a first predetermined temperature, The discharge temperature detected by the discharge temperature detecting means is not more than a second predetermined temperature, the outside air temperature detected by the outside air temperature detecting means is not less than a third predetermined temperature, and the current value detecting means A heat pump hot water supply apparatus, wherein when a state where the detected current value is equal to or less than a predetermined value α continues for a certain period of time, the air volume of the blower is lowered by a predetermined air volume by the blower air volume varying means. A heat pump hot water supply apparatus including a heat pump circuit in which a scroll compressor, a hot water supply heat exchanger, an expansion valve, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe, and detects discharge temperature of refrigerant discharged from the scroll compressor A temperature detection means, a target discharge temperature setting means for the temperature of the refrigerant discharged from the scroll compressor, a hot water temperature detection means for detecting the temperature of hot water after heat exchange in the hot water supply heat exchanger, and outside air Outside air temperature detecting means for detecting temperature, current value detecting means for detecting a current value flowing through the heat pump hot water supply device, a blower for sending air to the evaporator, and a blower air volume variable means for changing the air volume of the blower Provided, and after a predetermined time has elapsed since the scroll compressor was started, the tapping temperature detected by the tapping temperature detecting means is not more than a first predetermined temperature, The discharge temperature detected by the discharge temperature detecting means is not more than a second predetermined temperature, the outside air temperature detected by the outside air temperature detecting means is not less than a third predetermined temperature, and the current value detecting means When the state where the detected current value is equal to or less than the predetermined value α continues for a certain period of time, the target discharge temperature set by the target discharge temperature setting means is raised to a fourth predetermined temperature, and the blower air volume varying means A heat pump hot water supply apparatus characterized by lowering an air volume by a predetermined air volume. Target hot water temperature setting means for setting the target hot water temperature of the hot water after heat exchange with the hot water supply heat exchanger is provided, and the first predetermined temperature is determined from the target hot water temperature set by the target hot water temperature setting means. The heat pump hot-water supply device according to any one of claims 1 to 3, wherein the heat pump is obtained by subtracting a fifth predetermined temperature. Canceling raising the target discharge temperature set by the target discharge temperature setting means by a fourth predetermined temperature when the outside air temperature detected by the outside air temperature detection means is equal to or lower than an eighth predetermined temperature; 5. The heat pump hot water supply device according to claim 1, wherein lowering the air volume of the blower by a predetermined air volume by the blower air volume varying unit is released. A boiling number storage means for storing the number of times of boiling is provided, and when the number of times of boiling stored by the boiling number storage means exceeds a predetermined number, the target discharge temperature set by the target discharge temperature setting means is set. The release of raising the fourth predetermined temperature and / or releasing the lowering of the air flow of the blower by the blower air volume varying means is canceled. The heat pump hot water supply apparatus described in 1. An operation time storage means for storing the operation time is provided, and when the operation time stored by the operation time storage means exceeds a predetermined time, a target discharge temperature set by the target discharge temperature setting means is set to a fourth predetermined discharge temperature. The heat pump according to any one of claims 1 to 6, wherein the raising of only the temperature is released and / or the lowering of the air volume of the blower by the blower air volume varying means is released. Hot water supply device. Target discharge temperature setting means for setting a target value of the refrigerant temperature discharged from the scroll compressor is provided, and the second predetermined temperature is changed from the target discharge temperature set by the target discharge temperature setting means to the sixth predetermined temperature. The heat pump hot water supply apparatus according to any one of claims 1 to 7, wherein the heat pump hot water supply apparatus is one obtained by subtracting. A target hot water temperature setting means for setting a target hot water temperature of the hot water after being heat-exchanged by the hot water supply heat exchanger; and a second predetermined temperature is determined from the target hot water temperature set by the target hot water temperature setting means. The heat pump hot water supply device according to any one of claims 1 to 8, wherein the seventh predetermined temperature is added.

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