JP2008020189A - Refrigerating unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein an operation of a refrigerating unit is difficult to be stabilized and wherein trouble in the refrigerating unit is difficult to be evaded, by detecting a state of an inside of the refrigerating unit, since a state in a refrigerant circuit is difficult to be detected because a composition is included in a quantity of state of a refrigerant, in the refrigerating unit using a nonazeotropic refrigerant mixture. <P>SOLUTION: The circulation composition is detected in the refrigerating unit, and the state in the inside of the refrigerating unit is accurately detected using the circulation composition. The refrigerating unit is constituted to detect directly a value of the quantity of state, when the quantity of state not detected accurately exists because of an error of the detected circulation composition or the like. The trouble in the refrigerating unit is thereby detected accurately, and the state thereof is avoided thereby. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a refrigerant circuit and refrigerant circuit control of a refrigeration apparatus using a non-azeotropic refrigerant mixture.

FIG. 15 shows a conventional refrigeration apparatus using a non-azeotropic refrigerant mixture disclosed in JP-A-8-75280. Bypass from the compressor 1, the condenser 3, the first capillary 4, the evaporator 5, the refrigerant circuit in which the non-azeotropic refrigerant mixture circulates in the order connected by piping, and between the compressor 1 and the condenser 3 And a temperature detector for detecting the temperature and pressure of the bypass pipe 8 connected in order to the cooling means 9, the second capillary 10, the pipe between the compressor and the evaporator, and the outlet of the second capillary. 12 and a pressure detector 13, and a refrigeration apparatus provided with a composition calculator 14 that calculates a refrigerant composition circulating in the refrigerant circuit from signals detected by the temperature detector 12 and the pressure detector 13. With this refrigeration apparatus, the refrigerant composition circulating in the refrigerant circuit can be calculated, and the operation control of the refrigeration apparatus is performed with this refrigerant composition.

However, in the conventional technique, since the pressure of R407C is higher than that of R22 at the same temperature, the refrigeration apparatus using R407C is more likely to cause a refrigeration apparatus malfunction due to excessive compressor discharge section pressure rise than the refrigeration apparatus using R22 . In addition, in the refrigerator using ester oil / ether oil, which is the refrigerator oil used for R407C refrigerant and R407C, a lot of sludge that adversely affects the refrigeration apparatus is likely to occur .

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to use a non-azeotropic refrigerant mixture (including a pseudo-azeotropic refrigerant mixture) in a refrigeration apparatus without problems.

The refrigeration apparatus of the present invention is a refrigeration apparatus that uses a non-azeotropic mixed refrigerant or a pseudo-azeotropic mixed refrigerant as a refrigerant, and is provided with a compressor, a heat source unit side heat exchanger, a throttling device, and a use side heat exchanger. Non-azeotropic mixing from the compressor discharge side to the suction side of the refrigerant circuit, bypassing the heat source side heat exchanger, the expansion device, and the use side heat exchanger A bypass pipe for circulating the refrigerant or the pseudo-azeotropic mixed refrigerant, and an opening / closing output device that opens the opening / closing valve when the discharge temperature or pressure of the compressor is equal to or higher than a predetermined value and closes the opening / closing valve when the discharge temperature or pressure is lower than the predetermined value. Is.

A non-azeotropic refrigerant mixture (including a pseudo-azeotropic refrigerant mixture) can be used in the refrigeration apparatus without problems.

Reference Example 1 Hereinafter, this reference example will be described. FIG. 1 shows a refrigerating apparatus 81 which is an example of a refrigerating and air-conditioning apparatus using a non-azeotropic mixed refrigerant according to this reference example, and includes a compressor 1 having a variable capacity, a four-way valve 2, and a use side heat exchanger. A refrigerant circuit in which the machine heat exchanger 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source machine side heat exchanger, the accumulator 6, and the compressor 1 are connected in series in this order by piping; and Refrigerant in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order by switching the four-way valve. Configure the circuit. In addition, the first pressure detector 16 is provided in the circulation composition detector 15 and the discharge pipe of the compressor 1, and the second pressure detector 13 is provided in the suction pipe of the compressor 1. Further, the outdoor heat exchanger is provided with a variable capacity fan 7, a fan that outputs the rotation speed of the fan 7 and the frequency of the compressor 1, and a fan rotation speed / compressor frequency output device that is a compression function force variable means. 17. The capacity varying means may be separate from the fan capacity varying means and the compression function force varying means. 1 is filled with R407C, which is a non-azeotropic refrigerant mixture in which R32 / R125 / R134a is mixed at a ratio of 23/25/52 wt%. In the figure, the dotted line indicates that the control value is output in the direction of the arrow.

Next, the operation of the refrigeration apparatus 81 will be described. During heating, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 flows into the indoor unit heat exchanger 3 through the four-way valve 2 and is cooled by room temperature air or the like to be condensed and liquefied. The refrigerant discharged from the indoor unit heat exchanger 3 is depressurized by the first expansion device 4 and flows into the outdoor unit heat exchanger 5. The outdoor unit heat exchanger 5 generates a low temperature and the refrigerant evaporates and gasifies and flows out. The gas refrigerant flows into the accumulator 6 through the four-way valve 2 and passes through the accumulator 6 and is then sucked into the compressor 1. Excess refrigerant in the refrigeration apparatus 81 exists in the accumulator 6 in the form of liquid refrigerant. At this time, the condensation temperature of the indoor unit heat exchanger and the evaporation temperature of the outdoor unit heat exchanger can be changed by changing the rotation speed of the fan 7 or changing the frequency of the compressor 1 to change the rotation speed. During cooling, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 flows into the outdoor unit heat exchanger 5 through the four-way valve 2 and is cooled by room temperature air or the like to be condensed and liquefied. The refrigerant discharged from the outdoor unit heat exchanger 5 is decompressed by the expansion device 4 and flows into the indoor unit heat exchanger 3. The indoor unit heat exchanger generates a low temperature, and the refrigerant evaporates and gasifies and flows out. The gas refrigerant flows into the accumulator 6 through the four-way valve 2, passes through, and is sucked into the compressor 1. At this time, the condensation temperature of the outdoor unit heat exchanger and the evaporation temperature of the indoor unit heat exchanger can be changed by changing the rotation speed of the fan 7 or changing the frequency of the compressor 1 to change the rotation speed.

Next, the operation of the circulating composition detection device 15 will be described. In FIG. 1, 8 is a bypass pipe that bypasses the discharge pipe of the compressor 1 and the suction pipe of the compressor, 9 is a first double pipe heat exchanger, 10 is a first pressure reducing device, and 11 is a first temperature detector. , 12 is a second temperature detector, 13 is a second pressure detector, 14 is a composition calculator, and these bypass pipe 8, first double heat exchanger 9, first pressure reducing device 10, first temperature detector 11, the second temperature detector 12, the second pressure detector and the composition calculator 14 constitute a circulating composition detector 15. A part of the high-pressure gas refrigerant exiting the compressor 1 passes through the bypass pipe 8, exchanges heat with the low-pressure refrigerant in the first double pipe heat exchanger 9, liquefies, and then depressurizes in the first decompression device 10. And it becomes a low-pressure two-phase refrigerant. Thereafter, the first double-tube heat exchanger 9 evaporates by exchanging heat with a high-pressure refrigerant, gasifies, and returns to the suction of the compressor 1. In this apparatus, the temperature of the liquid refrigerant of the first temperature detector 11 and the temperature and pressure of the two-phase refrigerant of the second temperature detector 12 and the second pressure detector 13 are detected (the value of the second pressure detector 13). Since the outlet pressure of the first decompression device 10 is substantially equal, the outlet pressure of the first decompression device 10 is set to the value of the second pressure detector 13), and the non-azeotropic refrigerant mixture in the refrigeration device 81 is based on the temperature and pressure. The composition circulation device 14 calculates and detects the refrigerant circulation composition. The circulation composition detection is always performed while the refrigeration air conditioner is powered on. Here, a method for calculating the refrigerant circulation composition will be described. Since R407C is a non-azeotropic three-type mixed refrigerant, and the three types of refrigerant circulation composition are unknown numbers, the unknown circulation composition can be found by solving three equations. However, if each of the three types of circulation composition is given, it will be 1, so if R32 is expressed as α32, R125 is expressed as α125, and R134a is expressed as α134a, then α32 + α125 + α134a = 1 (1) always holds. If two equations (excluding α32 + α125 + α134a = 1) are established and solved, the circulation composition can be obtained. For example, if two equations that make α32 and α125 unknown are found, the circulation composition can be known. Now, how to establish an equation in which α32 and α125 are unknown will be described. First, the first equation can be established from the circulating composition detection device 15 of FIG. FIG. 2 is a Mollier diagram showing the state change of the refrigerant in the circulating composition detector 15. In this figure, 1) shows the state of the high-pressure gas refrigerant leaving the compressor 1, and 2) shows the double pipe. The heat exchanger 9 heat-exchanges with the low-pressure refrigerant and is liquefied. 3) The pressure is reduced by the decompression device 10 and becomes a low-pressure two-phase refrigerant. 4) The double-tube heat exchanger 9 It shows a gasified state after evaporating through heat exchange with the refrigerant. Since 2) and 3) in FIG. 2 are the same enthalpy, an equation can be established in which α32 and α125 are unknowns, 2) enthalpy and 3) are equal. That is, if the enthalpy of 2) is hl, the enthalpy of 3) is ht, the temperature of the first temperature detector 11 is T11, the temperature of the second temperature detector 12 is T12, and the pressure of the pressure detector 13 is P13, hl ( α32, α125, T11) = ht (α32, α125, T12, P13) (2). The second equation shows that as long as the filling composition initially put into the refrigeration system is R407C, gas-liquid equilibrium is established, and even after the liquid stays in the accumulator or the refrigerant leaks, it is between the components of the circulating composition. Have a certain relationship. That is, when A and B are constants, an empirical formula for vapor-liquid equilibrium composition can be established: α32 = A × α125 + B (3). By solving the two expressions (2) and (3) established as described above, α32, α125, and α134a can be obtained. And, from the equation of α32 = A × α125 + B and the equation of α32 + α125 + α134a = 1, if the value of one of the three kinds of components of the circulation composition is known, the values of the other compositions are also known from these equations, Hereinafter, α32 is also expressed as a representative value α of the circulation composition.

Further, in this reference example , a non-azeotropic three-type mixed refrigerant is used, but in the non-azeotropic two-type mixed refrigerant, the circulation composition can be obtained only by the remaining formulas other than the vapor-liquid equilibrium composition empirical formula.

Next, the composition in the refrigeration apparatus 81 will be described. The composition of the refrigerant circulating in the refrigeration cycle, including the composition of the gas refrigerant in the accumulator 6, circulates in the refrigeration cycle, so that the refrigerant has the same composition. Therefore, during heating, the gas refrigerant in the accumulator 6, the gas refrigerant discharged from the compressor 1, and the liquid refrigerant at the outlet of the indoor unit heat exchanger 3 have the same composition. Even during cooling, the gas refrigerant in the accumulator 6, the gas refrigerant discharged from the compressor 1, and the liquid refrigerant at the outlet of the outdoor unit heat exchanger 5 have the same composition. On the other hand, when considering the gas refrigerant and liquid refrigerant of the accumulator 6, the gas-liquid equilibrium relationship is established in the accumulator 6. When gas-liquid equilibrium is established in a non-azeotropic refrigerant mixture, the gas is a refrigerant containing more low-boiling components than liquid. Therefore, the gas refrigerant in the accumulator 6 is a refrigerant containing a larger amount of refrigerants R32 and R125 having a lower boiling point than the liquid refrigerant. Conversely, the liquid refrigerant in the accumulator 6 is a refrigerant containing a larger amount of refrigerant R134a having a higher boiling point than that of the gas refrigerant. The total refrigerant in the refrigeration apparatus 81 is a combination of the refrigerant circulating in the refrigeration apparatus 81 and the liquid refrigerant in the accumulator 6, and the composition of the combined refrigerant is the same as that of the refrigerant R407C filled. When the liquid refrigerant is present in the refrigerant 6, the composition of the refrigerant circulating in the refrigeration cycle in FIG. 1 including the composition of the gas refrigerant in the accumulator 6 contains more refrigerants R32 and R125 having a lower boiling point than the filled refrigerant. It becomes a refrigerant, and the composition of the liquid refrigerant in the accumulator 6 is a refrigerant containing a larger amount of refrigerant R134a having a higher boiling point than the composition of the filled refrigerant R407C. Further, when there is no liquid refrigerant in the accumulator 6, the composition of the refrigerant circulating in the refrigeration apparatus 81 in FIG. 1 is the same as that of R407C.

Next, the fan rotation speeds of the condensing temperature and evaporating temperature of the refrigerant circuit of this reference example and the operation control method of the compressor frequency output device 17 will be described. During the operation of the refrigeration system, the fan rotation speed and compressor frequency output device 17 determines the gas saturation temperature of P16 based on the detected value P16 of the first pressure detector 16 and the calculation of the composition calculator 14 and the detected circulating composition detection value α. The average value of the liquid saturation temperature and the liquid saturation temperature is obtained, and this value is set as the condensation temperature. Based on the detection value P13 of the second pressure detector 13 and the circulation composition detection value α, the average value of the gas saturation temperature and the liquid saturation temperature of P13 is obtained. This value is taken as the evaporation temperature. However, the value T12 of the second temperature detector 12 may be used as the evaporation temperature. The fan rotation speed / compressor frequency output device 17 compares the calculated condensation temperature and evaporation temperature with the respective target values incorporated therein, and calculates the rotation speed and compression of the fan 7 so that the target values are obtained. The frequency of the machine 1 is output to the fan 7 and the compressor 1, respectively. As a specific control example of the fan rotation speed and the compressor frequency output device 17, an increase in the condensation temperature and a decrease in the evaporation temperature or an increase in the frequency of the compressor 1 by increasing the frequency of the compressor 1 (increasing the rotation speed). Decrease in condensation temperature and increase in evaporation temperature due to lowering (reduction in rotational speed), decrease in condensation temperature during cooling due to increase in rotational speed of fan 7 (increase in fan air volume), increase in evaporation temperature during heating, or fan 7 in combination with an increase in the condensation temperature during cooling due to a decrease in the rotational speed (decrease in the fan air volume) and a decrease in the evaporation temperature during heating. Further, the control for changing the number of revolutions according to the frequency of the compressor 1 may be capacity control with a compressor provided with a so-called capacity control mechanism. In the reference example , the fan rotation speed and the compressor frequency output device 17 determine the condensing temperature and the evaporating temperature. However, a device for determining each of them or a device for determining both are provided, and these devices are provided. Thus, the condensing temperature and the evaporating temperature may be determined and output to the fan rotation speed and compressor frequency output device 17. In addition, in the case of a unit that operates at a constant frequency and constant indoor unit capacity where the change in condensation temperature or evaporation temperature is not large, only one of the controls, such as controlling only the fan or only the compressor, can be used. Good.

Reference Example 2 Reference Example 1 was control for keeping the condensation temperature and the evaporation temperature constant in order to ensure a constant capacity of the refrigerating and air-conditioning apparatus. However, when the refrigerant circulation composition changes, the condensation temperature and the evaporation temperature are constant. However, the condensation pressure and the evaporation pressure change. For this reason, the pressure difference at the inlet / outlet of the first expansion device 4 changes, and the flow rate of the refrigerant circuit and the refrigerant flow direction inlet subcool of the first expansion device 4 change. Accordingly, the flow rate of the refrigerant circuit and the subcooling direction inlet subcool of the first expansion device 4 change under the constant opening degree of the first expansion device 4 due to the change of the refrigerant circulation composition. The range of the opening varies depending on the refrigerant circulation composition. Therefore, as Reference Example 2, the minimum opening degree of the first throttle device 4 that can secure the flow rate of the refrigerant circuit and the inlet subcool of the first throttle device 4 in the flow direction of the refrigerant is determined for each refrigerant circulation composition or the change of the refrigerant circulation composition. You may set by the pressure difference of the 1st expansion device 4 which changes.

FIG. 3 shows a refrigerating apparatus 82 which is an example of a refrigerating and air-conditioning apparatus using a non-azeotropic refrigerant mixture related to this reference example . The compressor 1 having a variable capacity, the four-way valve 2, and a room which is a use side heat exchanger. A refrigerant circuit in which the machine heat exchanger 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source machine side heat exchanger, the accumulator 6, and the compressor 1 are connected in series in this order by piping; and Refrigerant in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order by switching the four-way valve. Configure the circuit. In addition, the first pressure detector 16 is connected to the circulation composition detector 15 and the discharge pipe of the compressor 1, the second pressure detector 13 is connected to the suction pipe of the compressor 1, and the fifth temperature detector is provided before and after the first throttle device 4. 35 and a sixth temperature detector 36, and an indoor unit heat exchanger has a seventh temperature detector 37 for detecting the room temperature. Furthermore, the outdoor heat exchanger 5 is provided with a variable capacity fan 7, a fan that outputs the rotational speed of the fan 7 and the frequency of the compressor 1, and a fan rotational speed / compressor frequency output that is a compression function force control means. And a sub-cool calculator 38 for calculating and outputting the degree of supercooling before and after the first throttling device 4. FIG. 3 is the same as the reference example 1 except that the expansion device minimum opening calculator 18, the fifth temperature detector 35, the sixth temperature detector 36, the seventh temperature detector 37, and the subcool calculator 38 are provided. Therefore, explanation is omitted.

Next, the subcool calculator 38 and the throttle device minimum opening calculator 18 will be described. The subcool calculator 38 is a temperature difference obtained by subtracting the value of the fifth temperature detector 35 from the value P16 of the first pressure detector 16 and the condensation temperature at the refrigerant circulation composition α during the cooling operation, and the first pressure during the heating operation. The temperature difference obtained by subtracting the value of the sixth temperature detector 36 from the value P16 of the detector 16 and the condensation temperature at the refrigerant circulation composition α is calculated, the subcooling of the first expansion device 4 is calculated, and this subcooling is calculated. The opening degree of the first expansion device 4 is controlled so as to be a predetermined target value. However, if the first throttling device 4 is controlled by the subcooling calculator 38, the refrigerant flow rate decreases even if the subcooling can be secured, and the capacity may become insufficient. There is a need. Therefore, the throttle device minimum opening calculator 18 receives the value P16 of the first pressure detector 16, the value P13 of the second pressure detector 13, and the refrigerant circulation composition α, and calculates the throttle device minimum opening X by the following equation. The output is controlled so that the first expansion device 4 does not become less than or equal to X to prevent the refrigerant flow from being insufficient due to excessive restriction. That is, the throttle device minimum opening output device 18 receives the opening command of the first throttle device 4 of the subcool calculator 38, and if this opening command is greater than X, the subcool calculator When the value is equal to or less than X, the command to set X is output to the first expansion device 4. By controlling in consideration of the refrigerant circulation composition α, the amount of refrigerant is not too small, and an optimal opening of the first expansion device 4 that can secure a subcool is ensured. During heating: X = K · (Tc-T37) / √ (P16-P13) (4) During cooling: X = K · (T37-Te) / √ (P16-P13) (5) where K is the aperture The minimum opening coefficient of the device, Tc is the condensation temperature calculated from P16 and α, Te is the evaporation temperature calculated from P13 and α, T37 is the indoor temperature of the indoor unit heat exchanger detected by the seventh temperature detector 37 is there. The equations (4) and (5) are derived as follows. The heat exchange amount between the indoor unit heat exchanger 3 and the refrigerant flowing through the indoor unit heat exchanger 3 is Q1, the heat exchange amount between the indoor unit heat exchanger 3 and the indoor unit side air is Q2, and the first expansion device 4 is opened. When the degree is Xa, Q1∝Xa · √ (P16−P13) (6) During heating: Q2∝ (Tc−T37) (7) During cooling: Q2∝ (T37−Te) (8) and Q1 = Since Q2, the heating time: Xa · √ (P16−P13) ∝ (Tc−T37) (9) The cooling time: Xa · √ (P16−P13) ∝ (T37−Te) (10) Based on (9) and (10), (4) and (5) can be established as an expression of X in which the lowest level refrigerant flow rate flows. In the control in which the evaporating temperature Te and the condensing temperature Tc are constant, √ (P16−P13) is a function of α, so that K is a function K (α) of α, and during heating: X = K (α) (Tc−T37) (11) During cooling: X = K (α) • (T37−Te) (12). In this reference example , the subcool calculator 38 determines the condensation temperature. However, a separate condensation temperature determination device may be provided and output to the subcool calculator 38. Further, the output of the opening instruction of the subcool calculator 38 and the output of the calculated minimum opening of the expansion device minimum opening calculator 18 is received and compared, and the opening command or the calculated minimum opening is sent to the first expansion device 4. A device for outputting the above may be provided separately.

Reference Example 3 FIG. 4 shows a refrigeration apparatus 83 which is an example of a refrigeration air-conditioning apparatus using a non-azeotropic refrigerant mixture related to this reference example , and includes a compressor 1, a four-way valve 2, and a indoor heat exchanger. A refrigerant circuit in which the machine heat exchanger 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source machine side heat exchanger, the accumulator 6, and the compressor 1 are connected in series in this order by piping; and Refrigerant in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order by switching the four-way valve. Configure the circuit. In addition, the first pressure detector 16 is provided in the circulation composition detector 15 and the discharge pipe of the compressor 1, and the second pressure detector 13 is provided in the suction pipe of the compressor 1. Further, the outdoor heat exchanger is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. Further, a first opening and closing valve 19 that outputs the opening and closing of the opening and closing valve 19 according to the value of the second pressure detector 13, a bypass pipe connecting the discharge pipe of the compressor 1 and the accumulator 6 and the second pressure reducing device 20 in series. An output device 21 is included. FIG. 4 is the same as the reference example 1 except for the piping in which the on-off valve 19 and the second pressure reducing device 20 are connected in series and the first on-off output device 21, and thus the description thereof is omitted.

Next, the control and operation of this reference example will be described. The first opening / closing output device 21 opens the opening / closing valve 19 when the value of the second pressure detector 13 is less than a predetermined value, for example, less than 1 kgf / cm 2 G, while the compressor 1 is in operation. Above cm2G, the on-off valve 19 sends a closing signal to the on-off valve 19, and the on-off valve 19 opens and closes by this signal. By this control, the high-temperature and high-pressure gas at the discharge portion of the compressor 1 is supplied to the accumulator after being reduced in pressure by the second pressure reducing device 20. At this time, the refrigerant containing a large amount of the low boiling point component R32 of the refrigerant R407C staying in the accumulator evaporates, and the refrigerant is supplied to the compressor 1. The refrigerant containing a large amount of R32 has a higher saturation pressure at the same temperature than the refrigerant of the R407C component. For this reason, the pressure of the suction part of the compressor 1 can be raised by the two effects that the refrigerant can be supplied to the compressor 1 and that the supplied refrigerant is a refrigerant having a high saturation pressure.

Further, the contact point between the pipe connecting the on-off valve 19 and the second pressure reducing device 20 and the accumulator 6 is not bent at the tip of the bypass pipe sideways as shown in FIG. When it opens, the liquid refrigerant in the accumulator does not easily enter the bypass pipe including the on-off valve 19 and the second pressure reducing device 20, and the high-temperature gas refrigerant is easily supplied into the refrigerant accumulated in the accumulator. Thereby, the refrigerant staying in the accumulator can be foamed, and the staying refrigerant can be efficiently evaporated. One end of the bypass pipe is connected to the accumulator 6, but it may be connected to the upstream or downstream pipe of the accumulator 6 as long as it is a suction pipe of the compressor.

When the temperature of the first embodiment is the same, the saturation pressure of R22 and R407C is higher by 2 kgf / cm 2 or more at a temperature of 50 ° C. Therefore, the discharge pressure of the compressor 1 is higher at R407C. Therefore, in Reference Example 3, when the value of the second pressure detector 13 is less than a certain value, the opening / closing valve 19 is opened to increase the suction portion pressure of the compressor 1, but when the opening / closing valve 19 is opened, the compressor 1 is opened. The compressor 1 may be protected by lowering the discharge section pressure.

FIG. 6 shows a refrigeration apparatus 84 which is an example of a refrigeration air-conditioning apparatus using a non-azeotropic refrigerant mixture according to the present invention. The compressor 1, the four-way valve 2, and an indoor unit heat exchanger which is a use side heat exchanger. 3. A first expansion device 4, an outdoor unit heat exchanger 5, which is a heat source side heat exchanger, an accumulator 6, and a compressor 1 are connected in series by piping in this order, and a four-way valve is switched. Thus, a refrigerant circuit in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order is configured. . In addition, the first pressure detector 16 is provided in the circulation composition detector 15 and the discharge pipe of the compressor 1, and the second pressure detector 13 is provided in the suction pipe of the compressor 1. Further, the outdoor heat exchanger is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. Also, a second opening / closing output that outputs opening / closing of the opening / closing valve 19 according to the value of the first pressure detector 16, a pipe connecting the opening / closing valve 19 connecting the discharge pipe of the compressor 1 and the accumulator 6 and the second pressure reducing device 20 device in series. It has a device 22. Since FIG. 6 is the same as Reference Example 1 except for the piping in which the on-off valve 19 and the second pressure reducing device 20 are connected in series and the second on-off output device 22, the description thereof is omitted.

Next, the control and operation of the present invention will be described. When the compressor 1 is in operation, the second opening / closing output device 22 closes the opening / closing valve 19 when the value of the first pressure detector 16 is determined in consideration of the pressure resistance of the unit, for example, less than 27 kgf / cm 2 G. At 27 kgf / cm 2 G or more, a signal for opening the opening / closing valve 19 is sent to the opening / closing valve 19, and the opening / closing valve 19 is opened / closed by this signal. Due to this control, a part of the high-temperature / high-pressure gas in the discharge part of the compressor 1 bypasses the accumulator through a pipe connecting the on-off valve 19 and the second pressure reducing device 20 in series. The pressure of decreases.

In another embodiment, the opening / closing pressure of the on-off valve 19 may be a function of the refrigerant circulation composition α within the range of the pressure resistance of the unit, taking into account that the saturation pressure varies depending on the refrigerant circulation composition. That is, the open / close pressure is increased or decreased depending on the saturation pressure, and in particular, it is possible to prevent a decrease in capacity due to a shortage of the refrigerant amount to the main circuit with a composition having a large saturation pressure. In the present embodiment, an HFC refrigerant having a higher saturation pressure at the same temperature than R22 is effective as the refrigerant.

Reference Example 4 Refrigerant R407C has a lower non-dielectric constant than refrigerant R22. Therefore, when the compressor is operated in a vacuum, R407C is more susceptible to corona discharge (such as a motor section short), and this phenomenon. Therefore, the compressor is easily damaged.

FIG. 7 shows a refrigeration apparatus 85 which is an example of a refrigeration air-conditioning apparatus using a non-azeotropic refrigerant mixture related to this reference example . The compressor 1, the four-way valve 2, and an indoor unit heat exchange which is a use side heat exchanger. A refrigerant circuit in which the condenser 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source side heat exchanger, the accumulator 6, and the compressor 1 are connected in series by piping in this order, and the four-way valve By switching, a refrigerant circuit in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order is configured. To do. In addition, the first pressure detector 16 is provided in the circulation composition detector 15 and the discharge pipe of the compressor 1, and the second pressure detector 13 is provided in the suction pipe of the compressor 1. Further, the outdoor heat exchanger is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. Moreover, it has the 1st compressor stop output device 23 which outputs the signal which stops the compressor 1 with the value of the 2nd pressure detector 13. FIG. Since FIG. 7 is the same as Reference Example 1 except for the first compressor stop output device 23, description thereof is omitted.

Next, the control and operation of this reference example will be described. The first compressor stop output device 23 stops the operation of the compressor 1 when the value of the second pressure detector 13 is a pressure indicating that the compressor performs a vacuum operation, for example, 0 kgf / cm 2 G or less. The compressor 1 is stopped in response to this signal. As a result, the compressor is not damaged by corona discharge that is likely to occur in R407C. As the refrigerant in this reference example , an HFC type refrigerant that is more susceptible to corona discharge than R22 is effective.

Second Embodiment Sludge that adversely affects the refrigerant circuit such as clogging of the throttle device increases when the discharge temperature of the compressor is high, and is often found when R407C is used as the refrigerant and ester oil or ether oil is used as the refrigerant oil. appear. Therefore, in the present invention, control is performed so that the discharge temperature of the compressor does not exceed a certain value.

FIG. 8 shows a refrigerating apparatus 86 as an example of a refrigerating and air-conditioning apparatus using a non-azeotropic refrigerant mixture according to the present invention. The compressor 1, the four-way valve 2, and an indoor unit heat exchanger that is a use side heat exchanger. 3. A first expansion device 4, an outdoor unit heat exchanger 5, which is a heat source side heat exchanger, an accumulator 6, and a compressor 1 are connected in series by piping in this order, and a four-way valve is switched. Thus, a refrigerant circuit in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order is configured. . In addition, the circulation composition detector 15 and the discharge pipe of the compressor 1 have a first pressure detector 16 and a third temperature detector 24, and the suction pipe of the compressor 1 has a second pressure detector 13. Further, the outdoor heat exchanger is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. Moreover, it has the piping which connected the on-off valve 19 which connects the discharge pipe of the compressor 1 and the accumulator 6, and the 2nd pressure reduction apparatus 20 apparatus in series. Moreover, it has the 3rd opening / closing output apparatus 25 which outputs opening / closing of the on-off valve 19 by the value of the 3rd temperature detector 24. FIG. FIG. 8 is the same as Reference Example 1 except for the piping in which the on-off valve 19 and the second pressure reducing device 20 are connected in series, the third temperature detector 24, and the third on-off output device 25, and thus the description thereof is omitted.

Next, the control and operation of the present invention will be described. When the compressor 1 is in operation, the third open / close output device 25 outputs a signal to open the open / close valve 19 when the value of the third temperature detector 24 is less than 120 ° C. The on-off valve 19 is opened and closed by this signal. Due to this control, a part of the high-temperature / high-pressure gas in the discharge part of the compressor 1 bypasses the accumulator through a pipe connecting the on-off valve 19 and the second pressure reducing device 20 in series. The pressure and temperature will decrease and sludge generation will decrease.

As another method, when the value of the third temperature detector 25 becomes 120 ° C. or higher while the compressor 1 is in operation, the operation of the compressor may be stopped.

Reference Example 5 When the superheat degree of the compressor discharge section is low during the operation of the compressor, the compressor liquid-compresses the refrigerant, and the compressor may be damaged. Therefore, in this reference example , the degree of superheat of the compressor discharge section is calculated from the pressure detector and temperature detector of the compressor discharge pipe and the value of the refrigerant circulation composition, and control is performed so that this value does not become less than a certain value.

FIG. 9 shows a refrigerating apparatus 87 which is an example of a refrigerating and air-conditioning apparatus using a non-azeotropic refrigerant mixture related to this reference example . The compressor 1, the four-way valve 2, and an indoor unit heat exchange which is a use side heat exchanger. A refrigerant circuit in which the condenser 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source side heat exchanger, the accumulator 6, and the compressor 1 are connected in series by piping in this order, and the four-way valve By switching, a refrigerant circuit in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order is configured. To do. In addition, the circulation composition detector 15 and the discharge pipe of the compressor 1 have a first pressure detector 16 and a third temperature detector 24, and the suction pipe of the compressor 1 has a second pressure detector 13. Further, the outdoor heat exchanger is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. In addition, the value of the third temperature detector 24 and the gas saturation temperature of the first pressure detector 16 (the refrigerant circulation composition α and the value of the first pressure detector 16 are input at the temperature when the liquid refrigerant is all gas refrigerant). And a second compressor stop output device 26 for outputting a stop of the compressor 1 based on this value. Since FIG. 9 is the same as Reference Example 1 except for the third temperature detector 24 and the second compressor stop output device 26, the description thereof is omitted.

Next, the control and operation of this reference example will be described. The second compressor stop output device 26 is configured such that when the compressor 1 is in operation, the value of the third temperature detector 24 and the pressure of the first pressure detector 16 are used to adjust the gas saturation temperature (when the liquid refrigerant has become all gas refrigerant). The difference value TdSH between the refrigerant circulation composition α and the first pressure detector 16 is input at the temperature, and this value is a predetermined value at which a predetermined degree of superheat cannot be obtained, that is, there is liquid compression. If the state of 20 degrees or less, which is the value of, continues for a predetermined time, for example, 10 minutes, the compressor 1 is stopped to prevent the compressor from being damaged.

As another method, the refrigeration apparatus as shown in FIG. 10 may be controlled as shown in FIG. FIG. 10 shows a refrigeration apparatus 88 which is an example of a refrigeration air-conditioning apparatus using a non-azeotropic refrigerant mixture related to this reference example . The compressor 1, the four-way valve 2, and an indoor unit heat exchange which is a use side heat exchanger. A refrigerant circuit in which the condenser 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source side heat exchanger, the accumulator 6, and the compressor 1 are connected in series by piping in this order, and the four-way valve By switching, a refrigerant circuit in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order is configured. To do. In addition, the circulation composition detector 15 and the discharge pipe of the compressor 1 have a first pressure detector 16 and a third temperature detector 24, and the suction pipe of the compressor 1 has a second pressure detector 13. Further, the outdoor heat exchanger is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. In addition, the value of the third temperature detector 24 and the gas saturation temperature of the first pressure detector 16 (the refrigerant circulation composition α and the value of the first pressure detector 16 are input at the temperature when the liquid refrigerant is all gas refrigerant). A throttle device opening reduction output device 27 is provided for calculating the value of the difference TdSH from the first throttle device 4 and reducing the opening of the first throttle device 4 by this value. FIG. 10 is the same as Reference Example 1 except for the third temperature detector 24 and the expansion device opening reduction output device 27, and therefore the description thereof is omitted.

Next, the control and operation of this reference example will be described. In FIG. 11, the contents of the control are as follows: the throttle device opening reduction output device 27 operates while the compressor 1 is operating, the value of the third temperature detector 24 and the gas saturation temperature of the first pressure detector 16 (all liquid refrigerant is gas refrigerant). The value TdSH of the difference between the refrigerant circulation composition α and the first pressure detector 16 is input at the temperature when the temperature becomes (step 1), and the predetermined superheat degree cannot be obtained. That is, it is determined whether or not a state where the liquid compression is present, for example, a state of 20 degrees or less continues for 10 minutes (step 2). The opening degree of the device 4 is closed by a predetermined amount, for example, 10 pulses (step 3). Then, the first expansion device 4 is closed until TdSH becomes larger than 20 degrees. By closing the first expansion device 4, the difference between the discharge and suction pressure of the compressor is increased, and the energy supplied to the refrigerant from the compressor is increased, so that the refrigerant is easily gasified.

Reference Example 6 When the temperature of the refrigeration oil in the compressor increases, the lubricity of the refrigeration oil decreases and the compressor may be damaged. However, the refrigerant circuit as in Reference Example 4 cannot accurately determine the temperature of the refrigerating machine oil (particularly, in R407C, since the refrigerant circulation composition error affects the refrigerating machine oil detection error, the refrigerating machine oil temperature is obtained from R22. Hateful). Therefore, in this reference example , a temperature detector is provided at a position where the temperature of the refrigeration oil in the compressor body can be measured, and the temperature of the temperature detector is not operated for a long time beyond a certain value to protect the compressor. Take control.

FIG. 12 shows a refrigerating apparatus 89 which is an example of a refrigerating and air-conditioning apparatus using a non-azeotropic refrigerant mixture related to this reference example . The compressor 1, the four-way valve 2, and an indoor unit heat exchange which is a use side heat exchanger. A refrigerant circuit in which the condenser 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source side heat exchanger, the accumulator 6, and the compressor 1 are connected in series by piping in this order, and the four-way valve By switching, a refrigerant circuit in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order is configured. To do. In addition, the fourth temperature detector 28 and the compressor 1 are disposed at positions where the temperature of the refrigerating machine oil at the lower part of the compressor 1 and the first pressure detector 16 can be detected in the circulation pipe 15 and the discharge pipe of the compressor 1. A second pressure detector 13 is provided in the suction pipe. Further, the outdoor heat exchanger is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. Moreover, it has the 3rd compressor stop output device 29 which outputs the stop of the compressor 1 by the value of the 4th temperature detector 28. FIG. Further, FIG. 12 is the same as Reference Example 1 except for the fourth temperature detector 28 and the third compressor stop output device 29, and the description thereof will be omitted.

Next, the control and operation of this reference example will be described. The third compressor stop output device 29 detects that the value of the fourth temperature detector 22 becomes a predetermined value, for example, 100 ° C. or more during the operation of the compressor 1, and this state continues for 60 minutes continuously. In this case, a signal for stopping the operation of the compressor 1 is output, and the compressor 1 stops.

Reference Example 7 When the concentration of the refrigerating machine oil in the compressor becomes low, the lubricity of the refrigerating machine oil decreases and the compressor may be damaged. Therefore, in this reference example , the concentration of the refrigeration oil in the compressor body is expressed as the difference between the temperature of the refrigeration oil and the gas saturation temperature of the refrigerant at the pressure on the compressor suction side, and this value does not operate for a long time beyond a certain value. In this way, control for protecting the compressor is performed.

FIG. 13 shows a refrigeration apparatus 89 which is an example of a refrigeration air-conditioning apparatus using a non-azeotropic refrigerant mixture related to this reference example . The compressor 1, the four-way valve 2, and an indoor unit heat exchange which is a use side heat exchanger. A refrigerant circuit in which the condenser 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source side heat exchanger, the accumulator 6, and the compressor 1 are connected in series by piping in this order, and the four-way valve By switching, a refrigerant circuit in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order is configured. To do. In addition, the fourth temperature detector 28 and the compressor 1 are disposed at positions where the temperature of the refrigerating machine oil at the lower part of the compressor 1 and the first pressure detector 16 can be detected in the circulation pipe 15 and the discharge pipe of the compressor 1. A second pressure detector 13 is provided in the suction pipe. Further, the outdoor heat exchanger 5 is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. Further, the value of the fourth temperature detector 28 and the gas saturation temperature of the second pressure detector 13 (the refrigerant circulation composition α and the value of the second pressure detector 13 are input at the temperature when all the liquid refrigerant becomes gas refrigerant). And a fourth compressor stop output device 30 for outputting an output for stopping the operation of the compressor 1 based on the value TsSH. FIG. 13 is the same as Reference Example 1 except for the fourth temperature detector 28 and the fourth compressor stop output device 30, and thus the description thereof is omitted.

Next, the control and operation of this reference example will be described. The fourth compressor stop output device 30 is the value of the fourth temperature detector 28 and the gas saturation temperature of the second pressure detector 13 during the operation of the compressor 1 (the temperature when all the liquid refrigerant becomes gas refrigerant). The difference value TsSH between the refrigerant circulation composition α and the second pressure detector 13) is a predetermined value indicating that a large amount of refrigerant is mixed in the refrigerating machine oil. It is detected that the state has continued for 60 minutes. In this case, a signal for stopping the operation of the compressor 1 is output, and the compressor 1 stops.

Reference Example 8 FIG. 14 shows a refrigeration apparatus 85 which is an example of a refrigeration air-conditioning apparatus using a non-azeotropic refrigerant mixture related to this reference example , and includes a compressor 1, a four-way valve 2, and a room which is a use side heat exchanger. A refrigerant circuit in which the machine heat exchanger 3, the first expansion device 4, the outdoor unit heat exchanger 5, which is a heat source machine side heat exchanger, the accumulator 6, and the compressor 1 are connected in series in this order by piping; and Refrigerant in which the compressor 1, the four-way valve 2, the outdoor unit heat exchanger 5, the first expansion device 4, the indoor unit heat exchanger 3, the accumulator 6, and the compressor 1 are connected in series by piping in this order by switching the four-way valve. Configure the circuit. In addition, the first pressure detector 16 is provided in the circulation composition detector 15 and the discharge pipe of the compressor 1, and the second pressure detector 13 is provided in the suction pipe of the compressor 1. Further, the outdoor heat exchanger is provided with a fan 7, and the rotation speed of the fan 7 and the compressor 1 are output by a fan rotation speed / compressor frequency output device 17 that outputs the rotation speed of the fan 7 and the frequency of the compressor 1. Calculate and change the frequency. Further, a first branch point 31 existing between the outdoor unit heat exchanger 5 and the first throttle device 4 and a second branch point 32 existing between the four-way valve 2 and the accumulator 6 are connected, and the second throttle device is connected. 33 and the outdoor unit heat exchanger 5 and a part between the first branch point 31 have a refrigerant circuit in which a second double pipe heat exchanger 34 for exchanging heat is connected in series with a pipe. The first branch point 31, the second branch point 32, the second expansion device 33, and the second double pipe heat exchanger 34 constitute a supercooling device. In FIG. 14, the first branch point 31 existing between the outdoor unit heat exchanger 5 and the first expansion device 4 and the second branch point 32 existing between the four-way valve 2 and the accumulator 6 are connected. Except for the refrigerant circuit in which the expansion device 33 and the outdoor unit heat exchanger 5 and the second double-tube heat exchanger 34 that exchanges heat with a part between the first branch point 31 are connected in series by a pipe, Reference Example 1 The explanation is omitted because it is the same.

Next, the operation of this reference example will be described. The refrigerant heat-exchanged by the outdoor unit heat exchanger 5 during cooling is exchanged with the low-pressure two-phase refrigerant depressurized from the first branch point through the second expansion device by the double-tube heat exchanger 26. Ensure the degree of cooling. At this time, in the case of R407C, the degree of supercooling is a value obtained by subtracting the in-situ temperature from the liquid saturation temperature at the in-situ pressure, and in R22, a value obtained by subtracting the in-situ temperature from the saturation temperature at the in-situ pressure. Become. For this reason, since it is difficult to secure the degree of supercooling in R407C, this reference example is effective. By ensuring the degree of supercooling, generation of refrigerant noise can be prevented in the indoor unit expansion device (first expansion device 4).

In each of the above-described embodiments, the description has been given mainly for the case of R407C as the refrigerant. However, the present invention can be applied to, for example, R404A and R407A that are non-azeotropic mixed refrigerants, and R410A and R410B that are pseudo-azeotropic mixed refrigerants. To do.

6 is a refrigerant circuit diagram in Reference Example 1. FIG. It is a Mollier diagram which shows the change of the refrigerant | coolant in the circulation composition detection circuit in the reference example 1. FIG. 6 is a refrigerant circuit diagram in Reference Example 2. FIG. FIG. 6 is a refrigerant circuit diagram in Reference Example 3 . It is a diagram of the connection of the accumulator and the hot gas refrigerant bypass pipe definitive to the embodiment of the present invention. It is a refrigerant circuit diagram definitive to an embodiment of the present invention. FIG. 6 is a refrigerant circuit diagram in Reference Example 4 . It is a refrigerant circuit diagram definitive to an embodiment of the present invention. FIG. 9 is a refrigerant circuit diagram in Reference Example 5 . 10 is another refrigerant circuit diagram in Reference Example 5. FIG. FIG. 10 is a control flowchart in Reference Example 5 . FIG. 9 is a refrigerant circuit diagram in Reference Example 6 . It is a refrigerant circuit figure in reference example 7 . 10 is a refrigerant circuit diagram in Reference Example 8. FIG. It is a refrigerant circuit in a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor, 3 Use side heat exchanger, 4 Expansion device, 5 Heat source side heat exchanger, 7 Fan, 13 2nd pressure detector, 15 Circulating composition detection device, 16 1st pressure detector, 17 Fan, compression Functional force control means, 18 throttle device minimum opening output device, 19 open / close valve, 20 pressure reducing device, 21 first open / close output device, 22 second open / close output device, 23 first compressor stop output device, 24 third temperature detection 25, third open / close output device, 26 second compressor stop output device, 27 throttle device opening reduction output device, 28 fourth temperature detector, 29 third compressor stop output device, 30 fourth compressor stop output Device, 31-34 supercooling device, 35, 36 temperature detector, 38 subcool calculator,

Claims (11)

A variable capacity compressor, a heat source machine side heat exchanger, a throttling device, a refrigerant circuit piped to a use side heat exchanger, a variable capacity fan for the heat source machine side heat exchanger, and a discharge pipe of the compressor In a refrigeration apparatus comprising a first pressure detector, a second pressure detector of a suction pipe of the compressor, and a refrigerant circulation composition detection device, and using a non-azeotropic refrigerant mixture,
The condensation temperature of the heat source unit side heat exchanger or the use side heat exchanger is determined from the refrigerant circulation composition detected by the circulation composition detection device and the detection pressure of the first pressure detector, and the circulation composition detection The evaporating temperature of the heat source machine side heat exchanger or the use side heat exchanger is determined from the refrigerant circulation composition detected by the apparatus and the detected pressure of the second pressure detector, and the condensing temperature and the evaporating temperature are respectively determined. A refrigeration apparatus comprising a fan for controlling the capacity of the compressor and the capacity of the heat source machine side heat exchanger so as to have a predetermined target value, and a compression function force control means. A refrigerant circuit in which a compressor, a heat source side heat exchanger, a throttling device, and a use side heat exchanger are connected by piping; a first pressure detector of a discharge pipe of the compressor; and a second pressure of a suction pipe of the compressor In a refrigeration apparatus comprising a detector, a refrigerant circulation composition detection device, and a temperature detector for detecting a refrigerant temperature upstream of the expansion device, and using a non-azeotropic refrigerant mixture,
The condensation temperature of the heat source apparatus side heat exchanger or the use side heat exchanger is determined from the refrigerant circulation composition detected by the circulation composition detection device and the detected pressure of the first pressure detector, and the condensation temperature and the temperature detection are determined. A subcool calculator for calculating a subcooling value of the refrigerant entering the expansion device from the detected temperature of the compressor, and issuing an opening degree command of the expansion device so that the subcooling value becomes a predetermined target value;
The minimum opening of the throttling device is calculated from the refrigerant circulation composition detected by the circulation composition detection device, the detection pressure of the first pressure detector, and the detection pressure of the second pressure detector. -If the opening command is larger than the calculated minimum opening, the opening command is compared.If the opening command is less than the calculated minimum opening, the calculated minimum opening is compared. And a throttling device minimum opening degree output device for outputting a squeezing device to the throttling device. Compressor, heat source side heat exchanger, expansion device, refrigerant circuit with pipe connection of use side heat exchanger, second pressure detector of suction pipe of compressor, on-off valve, pressure reducing device, compressor In a refrigeration apparatus comprising a bypass pipe connecting the discharge pipe and the suction pipe, and using a non-azeotropic refrigerant mixture,
A refrigeration apparatus comprising a first on-off output device that opens the on-off valve when the detected pressure of the second pressure detector is less than a predetermined value and closes the on-off valve when the detected pressure is higher than a predetermined value. Compressor, heat source side heat exchanger, expansion device, refrigerant circuit connected by piping, first pressure detector of discharge pipe of the compressor, on-off valve, pressure reducing device, compressor In a refrigeration apparatus comprising a bypass pipe connecting the discharge pipe and the suction pipe, and using a refrigerant having a higher saturation pressure at the same temperature than R22 as an HFC refrigerant,
A refrigeration apparatus comprising a second on-off output device that opens the on-off valve when the detected pressure of the first pressure detector is equal to or higher than a predetermined value and closes the on-off valve when the detected pressure is less than the predetermined value. A refrigerant circuit having a compressor, a heat source side heat exchanger, a throttling device, and a use side heat exchanger connected by piping; and a second pressure detector of the suction pipe of the compressor. In a refrigeration system that uses a refrigerant that is prone to corona discharge,
A first compressor stop output device is provided to stop the operation of the compressor when the detected pressure of the second pressure detector is equal to or less than a predetermined value indicating that the compressor performs a vacuum operation. Refrigeration equipment. Compressor, heat source side heat exchanger, expansion device, refrigerant circuit connected with piping, use side heat exchanger, third temperature detector of discharge pipe of the compressor, on-off valve, pressure reducing device, compressor In a refrigeration apparatus comprising a bypass pipe connecting the discharge pipe and the suction pipe, and using an HFC refrigerant as a refrigerant,
A refrigeration apparatus comprising a third on-off output device that opens the on-off valve when a detection value of the third temperature detector is equal to or greater than a predetermined value, and closes the on-off valve when the detection value is less than the predetermined value. A refrigerant circuit in which a compressor, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by piping, a first pressure detector of a suction pipe of the compressor, and a third temperature of a discharge pipe of the compressor In a refrigeration apparatus comprising a detector and a circulating composition detection device for refrigerant and using a non-azeotropic refrigerant mixture,
The superheat degree of the discharge pipe of the compressor is calculated from the detected values of the first pressure detector, the third temperature detector, and the refrigerant circulation composition detector, and the superheat degree is a predetermined value or less. Is provided with a second compressor stop output device for stopping the operation of the compressor when it continues for a predetermined time. A refrigerant circuit in which a compressor, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by piping, a first pressure detector of a suction pipe of the compressor, and a third temperature of a discharge pipe of the compressor In a refrigeration apparatus comprising a detector and a circulating composition detection device for refrigerant and using a non-azeotropic refrigerant mixture,
The superheat degree of the discharge pipe of the compressor is calculated from the detected values of the first pressure detector, the third temperature detector, and the refrigerant circulation composition detector, and the superheat degree is a predetermined value or less. A refrigeration apparatus comprising: a throttle device opening reduction output device that closes the opening of the throttle device by a predetermined amount when the operation continues for a predetermined time. In a refrigeration system comprising a refrigerant circuit in which a compressor, a heat source machine side heat exchanger, a throttling device, and a use side heat exchanger are connected by piping, and using a non-azeotropic refrigerant mixture,
When a fourth temperature detector for detecting the temperature of the refrigerating machine oil is included in the compressor, the detection value of the fourth temperature detector is a predetermined value or more, and when the state of the predetermined value or more continues for a predetermined time, A refrigeration apparatus comprising a third compressor stop output device for stopping the operation of the compressor. A compressor, a heat source side heat exchanger, a throttling device, a refrigerant circuit piped to the use side heat exchanger, a second pressure detector of the suction pipe of the compressor, and a refrigerant circulation composition detection device, In refrigeration equipment using non-azeotropic refrigerant mixture,
The difference between the temperature of the refrigerating machine oil detected by the fourth temperature detector in the compressor and the gas saturation temperature at the detected pressure of the second pressure detector is a predetermined value in the detected composition of the circulating composition detector of the refrigerant. A refrigeration apparatus comprising: a fourth compressor stop output device that stops the operation of the compressor when this state continues for a predetermined time. In a refrigeration system comprising a refrigerant circuit in which a compressor, a heat source machine side heat exchanger, a throttling device, and a use side heat exchanger are connected by piping, and using a non-azeotropic refrigerant mixture,
A refrigeration apparatus comprising a supercooling device that supercools a refrigerant between the heat source unit side heat exchanger and the expansion device during a cooling operation.

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