JPH08193756A - Freezer device - Google Patents

Abstract

PURPOSE: To prevent lubricant oil from being diluted with liquid refrigerant and to prevent a reduction in viscosity to keep a lubricated state in a compressing mechanism and to assure a reliability in operation of a compressor by a method wherein an occurrence of liquid refrigerant caused by condensation at a discharging part of the compressor is prevented or the liquid refrigerant is gasified and removed. CONSTITUTION: In the case that a refrigerant state at a discharging port of a compressor is detected by a refrigerant state sensing device 5 arranged at the discharging port of the compressor and the refrigerant state is judged as a two-phase state, a signal is sent from the refrigerant state sensing device 5 to a condensor fan controlling micro-computer 6 and the condensor fan 7 is controlled in such a manner that the number of rotation of a condensor fan 7 may be increased by one step.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is intended to reduce the viscosity of a refrigeration system by dissolving liquid refrigerant condensed inside a compressor shell during low load operation in a lubricating oil for maintaining the lubricity of a compression mechanism to reduce the viscosity. The present invention relates to a mechanism for preventing deterioration of the lubricating performance of the compressor and deterioration of the reliability of the compressor.

[0002]

2. Description of the Related Art In recent years, a refrigerating apparatus represented by an air conditioner has been required to perform a fine air conditioning operation according to a usage environment of a user. In the early air conditioners, the compressor was operated on and off intermittently at a constant frequency, so the hunting of the indoor temperature was large, that is, when the air conditioner was taken as an example, it became too cold or hot, and as a result, Users often feel uncomfortable in a warm environment. In order to overcome such problems, air conditioners have been developed which are equipped with an inverter and which adjust the operating frequency of the compressor according to the load. That is, the compressor operating frequency is increased when the load is large, and conversely, the operating frequency is decreased when the load is small, so that the capacity is controlled to create a comfortable thermal environment.

An operation control method for a current low load of a general household air conditioner will be described with reference to FIG. FIG. 25 is a schematic diagram of a configuration example of a conventional home air conditioner, in which 51 is a compressor, 52 is an outdoor unit heat exchanger, 53 is an indoor unit heat exchanger, 54 is an expansion valve, and 55 is an indoor unit. An air intake temperature measuring thermistor (hereinafter referred to as thermistor), 56 is a set temperature reading device (hereinafter referred to as remote controller), 57 is a load determination device (hereinafter referred to as microcomputer), 58 is a compressor operating frequency control device ( Hereinafter referred to as an inverter). When the air conditioner is operated, the thermistor 55 measures the indoor unit intake air temperature as room temperature, compares it with the set temperature set by the user with the remote controller 56, and the microcomputer 57 causes the operating frequency of the compressor 51 to be changed according to the temperature difference. Is determined and transmitted to the inverter 58, and the compressor 51 is operated at the determined operating frequency. For example, during the summer cooling operation, the temperature set by the remote controller 56 is 27 degrees, and the thermistor 55
If the room temperature detected in step 2 is 27.5 degrees, the temperature difference with respect to the set value is small, so the microcomputer 57 determines that the cooling load is small and instructs the inverter 58 to operate at a low frequency. As a result, the cooling capacity of the indoor unit is suppressed to a small level, and the indoor unit is operated so as to stabilize at the set temperature.

[0004]

However, the refrigerant state inside the shell of the compressor 51, which has a small operating load and is operated at a low frequency, has a two-phase state as shown in the Mollier diagram showing the refrigerant state in FIG. May become. That is, the refrigerant compressed by the compressor 51 and discharged is not at a temperature sufficient to completely vaporize inside the compressor shell, and the compressor shell temperature may be low depending on the temperature conditions of the atmosphere.
Therefore, a part of the discharged refrigerant may be condensed in the shell. The liquid refrigerant generated inside the compressor shell in this way dissolves in and is diluted with the lubricating oil for lubricating the compression mechanism existing at the bottom of the compressor 51, and as a result, the viscosity of the lubricating oil is reduced and the compression due to reduced lubricity is caused. This causes wear of the mechanism, which leads to a reduction in reliability of the compressor itself.

In view of the above problems, the present invention detects the refrigerant state at the discharge portion of the compressor, and according to the state, the heat release fluid flow rate of the condenser, the heat release fluid flow rate of the evaporator, the compressor operating frequency, and the pressure reducing device throttle. By controlling the amount and heating means input so that the refrigerant at the compressor discharge is kept as heating gas,
(EN) A refrigeration system capable of preventing the refrigerant from condensing inside the compressor in a refrigeration system during low-load operation and thus ensuring the reliability of the compressor 51.

[0006]

In order to solve the above-mentioned problems, a refrigerating apparatus of the present invention comprises a compressor, a condenser, a pressure reducing device,
In a vapor compression refrigeration system configured by communicating an evaporator with a refrigerant pipe, a discharged refrigerant state detection means for detecting a refrigerant state in the compressor discharge part, and a refrigerant state detected by the discharged refrigerant state detection means And a condenser heat-radiating fluid flow rate control means for controlling the flow rate of the heat-radiating fluid in the condenser.

Another refrigeration system of the present invention is a compressor,
In a vapor compression refrigeration system configured by connecting a condenser, a decompressor, and an evaporator with a refrigerant pipe, a discharged refrigerant state detecting means for detecting a refrigerant state in the compressor discharge part, and the discharged refrigerant state detecting means. And an evaporator heat-absorbed fluid flow rate control means for controlling the flow rate of the heat-absorbed fluid in the evaporator according to the state of the refrigerant detected in.

Another refrigeration system of the present invention is a compressor,
In a vapor compression refrigeration system configured by connecting a condenser, a decompressor, and an evaporator with a refrigerant pipe, a discharged refrigerant state detecting means for detecting a refrigerant state in the compressor discharge part, and the discharged refrigerant state detecting means. The operating capacity control means for controlling the operating capacity of the compressor in accordance with the refrigerant state detected in Step 1.

Another refrigeration system of the present invention is a compressor,
In a vapor compression refrigeration system configured by connecting a condenser, a variable capacity decompressor, and an evaporator with refrigerant pipes, a discharged refrigerant state detection means for detecting a refrigerant state in the compressor discharge part, and the discharged refrigerant state A throttle amount control means for controlling the throttle amount in the variable pressure reducing device according to the refrigerant state detected by the detecting means.

Another refrigeration system of the present invention is a compressor,
In a vapor compression refrigeration system configured by connecting a condenser, a decompression device, and an evaporator with a refrigerant pipe, a discharged refrigerant state detection means for detecting a refrigerant state in the compressor discharge part, and a lubrication inside the compressor Heating means arranged to heat a liquid pool composed of a mixed phase of oil and liquid refrigerant, and heating amount control means for controlling the heating amount in the heating means according to the refrigerant state detected by the discharged refrigerant state detecting means. And have.

Further, in another refrigerating apparatus of the present invention, the heating means is arranged in the interior of the compressor near a suction port of an oil pump mechanism for pumping up the lubricating oil stored therein. It has an oil suction temperature detection means for detecting the temperature of the suction port of the pump mechanism.

Further, another refrigerating apparatus of the present invention is arranged vertically above the suction port of the oil pump mechanism for pumping up the stored lubricating oil inside the compressor.

Further, in another refrigerating apparatus of the present invention, as discharge refrigerant state detecting means, discharge temperature detecting means for detecting the refrigerant temperature at the compressor discharge and discharge pressure for detecting the refrigerant pressure at the compressor discharge are also provided. The discharge temperature lower limit value determining unit determines the discharge temperature lower limit value based on the temperature and pressure detected by the discharge temperature detecting unit and the discharge pressure detecting unit.

In another refrigerating apparatus of the present invention, as discharge refrigerant state detecting means, discharge temperature detecting means for detecting the refrigerant temperature at the discharge of the compressor and a condenser for detecting the temperature of the refrigerant flowing through the condenser. The refrigerant temperature detecting means and the discharge lower limit temperature determining means for determining the lower limit value of the compressor discharge temperature based on the temperature detected by the condenser refrigerant temperature detecting means.

[0015]

The present invention has the following functions due to the above-mentioned structure.

That is, when the refrigerant state at the compressor discharge portion is detected and the refrigerant state is a two-phase state, the heat radiation fluid flow rate control means for the condenser increases the flow rate of the heat radiation fluid in the condenser. By doing so, the condenser capacity is improved, and as a result, the evaporator capacity is also improved so that the compressor sucks the refrigerant in a higher dryness state, and the refrigerant at the compressor discharge is not in the two-phase state. It will be possible to keep it to become overheated gas. As described above, the refrigerant compressed and discharged by the compressor does not condense inside the compressor shell, and thus it is possible to prevent the viscosity of the lubricating oil in the compressor from lowering with a simple and inexpensive structure. .

Further, when the refrigerant state at the compressor discharge portion is detected and the refrigerant state is a two-phase state, the flow rate of the heat-absorbed fluid in the evaporator is increased by the evaporator heat-absorbed fluid flow rate control means. By doing so, we aim to improve the evaporator capacity,
By allowing the compressor to suck in a refrigerant having a higher degree of dryness, the refrigerant discharged at the compressor can be maintained as a superheated gas instead of a two-phase state. Moreover, the control response is better than that in the case where the condenser capacity is improved, and the controllability for making the refrigerant in the compressor discharge into the superheated gas state can be further enhanced. As described above, the refrigerant compressed and discharged by the compressor does not condense inside the compressor shell, and thus it is possible to prevent the viscosity of the lubricating oil in the compressor from lowering with a simple and inexpensive structure. .

When the refrigerant state at the compressor discharge portion is detected and the refrigerant state is a two-phase state, the operating capacity control means operates the compressor at a higher capacity to circulate the refrigerant in the refrigeration cycle. By increasing the amount, the capacity of the condenser and evaporator is improved, and as a result, the refrigerant in the state of higher dryness is sucked into the compressor, and the refrigerant at the discharge of the compressor is not in the two-phase state but overheated gas. Will be able to keep it. In addition, when the compressor operating capacity is controlled to correct the refrigeration cycle, there is an advantage that a wider range of refrigerating cycle capacity control can be expected as compared with the case where the heat exchange and heat absorption fluid flow rate control is performed by the heat exchanger. As described above, the refrigerant compressed / discharged by the compressor is prevented from condensing inside the compressor shell, so that the viscosity of the lubricating oil in the compressor can be more reliably prevented with a simple and inexpensive structure. It will be possible.

Further, when the refrigerant state in the compressor discharge portion is detected and the refrigerant state is a two-phase state, the amount of refrigerant circulation in the refrigeration cycle is controlled by controlling the throttle amount in the variable capacity decompressor. Control so that the compressor sucks the refrigerant in a higher dryness state or in a superheated gas state,
It becomes possible to keep the refrigerant at the compressor discharge as a superheated gas rather than a two-phase state. Further, when the refrigeration cycle is corrected by controlling the throttle amount in the variable capacity decompressor, the refrigeration cycle has the same correction capacity as that when the compressor operating capacity is controlled, and the refrigeration apparatus accompanying the correction of the refrigeration cycle is also provided. There is an advantage that the input to the air conditioner is reduced and a more efficient refrigeration cycle can be realized. As described above, the refrigerant compressed and discharged by the compressor is prevented from condensing inside the compressor shell, and thus with a simple and inexpensive structure, it is possible to more reliably prevent the viscosity of the lubricating oil in the compressor from lowering, Moreover, it becomes possible to realize a highly efficient refrigeration cycle.

Further, when the refrigerant state at the discharge portion of the compressor is detected and the refrigerant state is a two-phase state, it is possible to heat the liquid pool consisting of a mixed phase of lubricating oil and liquid refrigerant inside the compressor. By directly heating the liquid pool with the provided heating means and vaporizing the liquid refrigerant dissolved in the lubricating oil, even if liquid refrigerant due to condensation occurs in the compressor, the lubricating oil is diluted with the liquid refrigerant. It is possible to prevent the decrease in the viscosity of the lubricating oil in the compressor more reliably with a simple structure.

Further, in heating the liquid pool composed of the mixed phase of the lubricating oil and the liquid refrigerant inside the compressor, the heating means is arranged near the suction port of the oil pump mechanism for pumping the lubricating oil, and further, the oil pump mechanism. By having an oil suction temperature detection means that detects the temperature of the suction port of
The temperature of the liquid refrigerant mixed with the lubricating oil that is about to be pumped up is directly controlled so that it is removed by heating and vaporizing it. Therefore, liquid refrigerant is generated due to condensation inside the compressor. Even in this case, it is possible to more efficiently prevent the lubricating oil from being diluted with the liquid refrigerant. Moreover, since the heating means only needs to heat the liquid pool near the inlet of the oil pump mechanism, a smaller-scale heating means can be used, that is, with a cheaper configuration, the viscosity of the lubricating oil in the compressor can be more reliably achieved. It is possible to prevent the decrease.

Further, in heating the liquid pool composed of the mixed phase of the lubricating oil and the liquid refrigerant inside the compressor, the heating means is arranged vertically above the suction port of the oil pump mechanism for pumping the lubricating oil. By so doing, it is possible to prevent the gas refrigerant heated and vaporized by the heating means from being sucked into the oil pump, suck up only the liquid lubricating oil, and reliably lubricate the compression mechanism with a simple structure. Become.

Further, as discharge refrigerant state detecting means, discharge temperature detecting means for detecting the refrigerant temperature at the compressor discharge, discharge pressure detecting means for detecting the refrigerant pressure at the compressor discharge,
By having the discharge temperature detecting means and the discharge temperature lower limit value determining means for determining the discharge temperature lower limit value based on the temperature and pressure detected by the discharge pressure detecting means, it is common to other main body controls of the refrigerating apparatus. It is possible to accurately estimate the refrigerant state at the compressor discharge by using a sensor that can be used as a simple structure, and use the result easily for control to avoid the two-phase state of the compressor discharge. It will be possible.

As the discharged refrigerant state detecting means, a discharge temperature detecting means for detecting the refrigerant temperature at the discharge of the compressor, and a condenser refrigerant temperature detecting means for detecting the temperature of the refrigerant flowing through a specific portion on the pipe of the condenser. Means and a discharge temperature lower limit value determining means for determining the compressor discharge temperature lower limit value based on the temperature detected by the condenser refrigerant temperature detecting means, thereby measuring the pressure more expensive than the temperature detecting means. It is easy to obtain without using any means, and by predicting the refrigerant state in the compressor discharge by using only the temperature detection means that has been widely used from the past, the refrigerant in the compressor discharge is cheaper and simpler in structure. It becomes possible to make a state estimation.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the accompanying drawings. It should be noted that the following examples are examples of embodying the present invention and are not intended to limit the comprehensive scope of the present invention.

First, the configuration of the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram of the configuration of a refrigerating apparatus according to the first embodiment of the present invention. In the figure, 1 is a compressor, 2 is a condenser, 3 is an expansion valve (pressure reducing mechanism), 4 is an evaporator, and these are sequentially connected in an annular shape using a refrigerant pipe. Reference numeral 5 denotes a discharge refrigerant state detecting means at the discharge of the compressor, and details thereof are, for example, as shown in an example of the discharge refrigerant state detecting means of FIG. 2, a thermistor 5a for measuring the temperature of the refrigerant at the discharge of the compressor. And a pressure gauge 5 for measuring the compressor discharge pressure near the thermistor 5a.
b, the saturated vapor temperature (Tsat) at the compressor discharge pressure is referred to or calculated based on the signal from the pressure gauge 5b, the temperature measured by the thermistor 5a is compared, and the refrigerant discharged at the compressor is discharged. It is composed of a microcomputer 5c which determines a state and issues a control command. Further, 6 is a condenser fan control microcomputer (condenser heat radiating fluid flow rate control means), and 7 is a condenser fan unit. The refrigerant state at the discharge of the compressor is detected by the compressor detecting means 5, and when it is judged that the microcomputer 5c in the compressor detecting means needs to control, a control signal is transmitted to the condenser fan controlling microcomputer 6 and the condenser fan unit. The number of rotations of 7 is controlled so as to change.

Next, a method of determining the compressor discharge temperature lower limit value in the present invention will be described with reference to FIG. FIG. 3 is a graph of a saturated vapor line approximation formula, in which the compressor discharge pressure (Pdis) measured by the pressure gauge 5b is compressed by the functional formula f (P) according to the refrigerant used as the working fluid. The machine discharge saturated vapor temperature (Tsat) is calculated. Note that Pd
Even if Tsat for is is given in the form of table in the microcomputer 5c, the same function is achieved. Here, in the microcomputer 5c, the compressor discharge temperature (Tdis) measured by the thermistor 5a is compared with Tsat in order to prevent the refrigerant state in the compressor discharge from being a two-phase state, which is the object of the present invention. The temperature difference (ΔT) to be taken is preset, and the compressor discharge temperature lower limit value Tdisx1 = Tsa
Calculated as t + ΔT. Now, if Tdis ≧ Tdisx1, it means that the refrigerant is not in the two-phase state at the discharge of the compressor, and conversely, if Tdis <Tdisx1, the refrigerant is at the two-phase state in the discharge of the compressor, and a control process for avoiding this state Will be determined to need.

Next, a specific control method for solving the problems will be described as a first embodiment of the present invention with reference to FIGS. 4 and 5. First, FIG. 4 is a control flowchart in the first embodiment of the present invention, and FIG. 5 is a Mollier diagram showing changes in the refrigeration cycle due to the control in the same embodiment. In FIG. 4, when the operation of the refrigeration system is started, Pdis and Tdis are measured, then Tsat is calculated based on Pdis, and the compressor discharge temperature lower limit value is Tdi.
It is determined by sx1 = Tsat + ΔT. And Tdis
And Tdisx1 are compared, and Tdis ≧ Tdisx1
If it is, the operating state is maintained as it is, but Tdi
When s <Tdisx1, the microcomputer 5c issues a control command to the condenser fan control microcomputer 6 so as to increase the rotation speed of the condenser fan unit 7 by one step. As a result, the condenser capacity increases as well as the evaporator capacity, allowing the compressor intake to draw in a drier or superheated refrigerant, and is therefore indicated by the dotted line in FIG. As described above, the refrigeration cycle in which the compressor discharge is in the two-phase state is changed to the refrigeration cycle in which the compressor discharge becomes the overheated gas state, and the generation of the liquid refrigerant in the compressor discharge part can be avoided.

As described above, when the refrigerant state in the compressor discharge portion is detected and the refrigerant state is the two-phase state,
By increasing the flow rate of the heat-releasing fluid in the condenser by the heat-radiating fluid flow control means of the condenser, the condenser capacity is improved, and as a result, the evaporator ability is also improved and the dryness of the compressor is higher. Intake the refrigerant in the state,
It becomes possible to keep the refrigerant at the compressor discharge as a superheated gas rather than a two-phase state. Therefore, the refrigerant compressed and discharged by the compressor does not condense inside the compressor shell, and thus it is possible to prevent the viscosity of the lubricating oil in the compressor from decreasing with a simple and inexpensive structure.

Next, a second embodiment of the present invention will be described with reference to FIG.
Will be explained. FIG. 6 is a schematic diagram of the configuration of the refrigerating apparatus of the second embodiment of the present invention. The difference with the configuration of the first embodiment is that the fan control for correcting the refrigeration cycle is not for the condenser 2 but for the evaporator 4. As shown in the figure, it has an evaporator fan control microcomputer (evaporator radiated fluid flow rate control means) 8 and an evaporator fan unit 9. Further, the method of judging the refrigerant state at the discharge of the compressor is the same as that of the first embodiment, and therefore the explanation is omitted here.

Next, a specific control method for solving the problem in the second embodiment of the present invention will be described with reference to FIGS. 7 and 8. First, FIG. 7 is a control flowchart in the second embodiment of the present invention, and FIG. 8 is a Mollier diagram showing changes in the refrigeration cycle due to the control in the same embodiment.
In FIG. 7, first, when the operation of the refrigeration system is started, Pd
is and Tdis are measured, then T based on Pdis
sat is calculated, and the compressor discharge temperature lower limit value is Tdisx.
1 = Tsat + ΔT. And Tdis and T
Disx1 is compared, and if Tdis ≧ Tdisx1, the operating state is maintained as it is, but Tdis <
In the case of Tdisx1, the control command is issued from the microcomputer 5c to the evaporator fan control microcomputer 8 so as to increase the rotation speed of the evaporator fan unit 7 by one step. As a result, the capacity of the evaporator is increased, and it becomes possible to suck in a refrigerant having a higher degree of dryness or a superheated gas state in the suction of the compressor, and therefore, as shown by the dotted line in FIG. It is possible to avoid the generation of the liquid refrigerant in the compressor discharge part by changing the refrigeration cycle in the phase state to a refrigeration cycle in which the compressor discharges the superheated gas state.

As described above, when the refrigerant state at the compressor discharge portion is detected and the refrigerant state is the two-phase state,
By increasing the flow rate of the heat-absorbed fluid in the evaporator 4 by the evaporator heat-absorbed-fluid flow rate control means 8, the evaporator capacity is improved and the compressor 1 sucks the refrigerant in a higher dryness state. Therefore, the refrigerant discharged from the compressor can be maintained as a superheated gas instead of a two-phase state. Moreover, the control response is better than that in the case where the condenser capacity is improved, and the controllability for making the refrigerant in the compressor discharge into the superheated gas state can be further enhanced. Therefore, the refrigerant compressed and discharged by the compressor 1 does not condense inside the compressor shell, so that it is possible to prevent the viscosity of the lubricating oil in the compressor from lowering with a simple and inexpensive structure.

Next, a third embodiment of the present invention will be described with reference to FIG.
Will be explained. FIG. 9 is a schematic diagram of a refrigerating apparatus configuration according to a third embodiment of the present invention. The difference from the first and second embodiments is that the control for refrigeration cycle correction is performed by a heat radiated / heat absorbing fluid of a heat exchanger. This is not done for the flow rate, but for the operating capacity of the compressor 1. As shown in the figure, the inverter (compressor operating capacity control means) 10
Have. The method of determining the refrigerant state at the discharge of the compressor is the same as that of the first embodiment, and therefore the description is omitted here.

Next, a specific control method for solving the problem in the third embodiment of the present invention will be described with reference to FIGS. First, FIG. 10 is a control flowchart in the third embodiment of the present invention, and FIG. 11 is a Mollier diagram showing changes in the refrigeration cycle due to the control in the same embodiment. In FIG. 10, first, when the operation of the refrigeration system is started, Pdis and Tdis are measured, and then Pdis
Tsat is calculated based on the above equation, and the compressor discharge temperature lower limit value is determined by Tdisx1 = Tsat + ΔT. And T
dis and Tdisx1 are compared, and Tdis ≧ Tdi
In the case of sx1, the compressor operating frequency is decreased step by step up to the predetermined operating frequency instructed by the refrigeration system, but in the case of Tdis <Tdisx1, the microcomputer 5c
A control command is issued to the inverter 10 to increase the compressor operating frequency by one step. As a result, the heat exchanger capacity is increased, and it becomes possible to suck the refrigerant having a higher degree of dryness or a superheated gas state in the suction of the compressor, and therefore, as shown by the dotted line in FIG. The refrigeration cycle that has been in the two-phase state is changed to a refrigeration cycle in which the compressor discharges into a superheated gas state, and the generation of liquid refrigerant in the compressor discharge part can be avoided.

As described above, when the refrigerant state at the compressor discharge portion is detected and the refrigerant state is a two-phase state,
The capacity of the circulating refrigerant in the refrigeration cycle is increased by operating the compressor 1 at a higher capacity by the operating capacity control means, thereby improving the capacity of the condenser 2 and the evaporator 4, and as a result, the dryness of the compressor 1 is improved. The refrigerant in a higher state is sucked in so that the refrigerant at the discharge of the compressor can be maintained as a superheated gas instead of a two-phase state. Moreover, in this case, since the compressor operating capacity is controlled to correct the refrigeration cycle, there is an advantage that a wider range of refrigeration cycle capacity control can be expected as compared to the case of controlling the heat radiation / heat absorption fluid flow rate with the heat exchanger. is there. Therefore, the refrigerant compressed and discharged by the compressor 1 does not condense inside the compressor shell, so that the viscosity of the lubricating oil in the compressor can be prevented from decreasing with a simple and inexpensive structure. It will be possible.

Next, the fourth embodiment of the present invention will be described with reference to FIG.
2 is used for the explanation. FIG. 12 is a schematic diagram of a refrigerating apparatus configuration according to the fourth embodiment of the present invention. The difference from the first, second and third embodiments is that the control for refrigerating cycle correction is performed by the heat release of the heat exchanger.・ The point is that it is performed not for the heat absorbing fluid flow rate or for the compressor operating capacity, but for the throttle amount of the decompression device. It has a valve (variable pressure reducing device) 11 and an electric expansion valve control microcomputer (throttle amount control means) 12. The method of determining the refrigerant state at the discharge of the compressor is the same as that of the first embodiment, and therefore the description is omitted here.

Next, a specific control method for solving the problem in the fourth embodiment of the present invention will be described with reference to FIGS. 13 and 14. First, FIG. 13 is a control flowchart in the fourth embodiment of the present invention, and FIG. 14 is a Mollier diagram showing changes in the refrigeration cycle due to the control in the same embodiment. In FIG. 13, when the operation of the refrigeration system is started, Pdis and Tdis are measured first, and then Pdis
Tsat is calculated based on the above equation, and the compressor discharge temperature lower limit value is determined by Tdisx1 = Tsat + ΔT. And T
dis and Tdisx1 are compared, and Tdis ≧ Tdi
In the case of sx1, it is controlled to open the valve step by step up to a predetermined expansion valve opening determined by the refrigeration system.
When Tdis <Tdisx1, the expansion valve opening degree is set to 1 by the microcomputer 5c with respect to the electric expansion valve control microcomputer 12.
A control command is issued to close each step. As a result, the heat exchanger capacity is increased, and it becomes possible to suck in a refrigerant having a higher degree of dryness or a superheated gas state in the suction of the compressor, and therefore, as shown by a dotted line in FIG. The refrigeration cycle that was in the two-phase state changed to a refrigeration cycle in which the compressor discharges into a superheated gas state,
It is possible to avoid the generation of the liquid refrigerant in the compressor discharge part.

As described above, when the refrigerant state at the compressor discharge portion is detected and the refrigerant state is the two-phase state,
By controlling the amount of throttling in the variable capacity decompressor 11, the heat exchanger capacity is improved, and the compressor 1 sucks the refrigerant in a higher dryness state or in a superheated gas state, and It should be possible to keep the refrigerant at discharge as a superheated gas rather than a two-phase state. Further, when the refrigeration cycle is corrected by controlling the throttle amount in the variable capacity depressurizer 11 in this way, the refrigeration cycle has the same effective correction capacity of the refrigeration cycle as compared with the case where the compressor operating capacity is controlled, and the refrigeration cycle is increased. The input to the refrigeration system accompanying the modification of the cycle is reduced, and there is a merit that a more efficient refrigeration cycle can be realized. Therefore, the compressor 1
Refrigerant compressed and discharged in the compressor will not condense inside the compressor shell. With this simple and inexpensive structure, it is possible to more reliably prevent the viscosity of the lubricating oil in the compressor 1 from decreasing and to achieve high efficiency refrigeration. It becomes possible to realize the cycle.

Next, a fifth embodiment of the present invention will be described with reference to FIG.
5 and FIG. 16. FIG. 15 is a schematic diagram of the configuration of the refrigerating apparatus according to the fifth embodiment of the present invention. The difference from the first to fourth embodiments is that after the generation of the liquid refrigerant at the discharge of the compressor is detected, the liquid pool in the compressor 1 is heated and melted as a means for avoiding a decrease in the viscosity of the lubricating oil by the liquid refrigerant. A heater (heating means) 13a arranged to heat the liquid pool in the compressor 1 in order to vaporize the liquid refrigerant;
It has a heater controller (heating amount control means) 14 for controlling the output of the heater 13a in response to a signal from the microcomputer 5c. The method of determining the refrigerant state at the discharge of the compressor is the same as that of the first embodiment, and therefore the description is omitted here.

Next, a concrete control method for solving the problems in the fifth embodiment of the present invention will be described with reference to FIGS.
-2, It demonstrates using FIG. 17, FIG. First, Fig. 16-
1 is a schematic configuration diagram of an example of the compressor 1, and FIG. 16-2 is a detailed diagram of a heating device arrangement example in the compressor 1. FIG.
-2, for example, in a general vertical rotary compressor, the lubricating oil is stored at the bottom of the compressor 1, and the generated liquid refrigerant is mixed with the lubricating oil here. And become a liquid pool. For lubrication of the compression mechanism, a liquid pool is sucked up from the oil suction port shown in the figure and sent to each part of the compression mechanism. The heater 13a according to the present invention is arranged so as to be in contact with the liquid pool portion and to heat and vaporize the liquid refrigerant directly melted in the liquid pool. 17 is a control flowchart in the fifth embodiment of the present invention, and FIG. 18 is a Mollier diagram showing changes in the refrigeration cycle due to the control in the same embodiment. FIG. 17
First, when the operation of the refrigeration system is started, Pdis
And Tdis are measured, and then Tsa based on Pdis
t is calculated, and the compressor discharge temperature lower limit value is Tdisx1 =
It is determined by Tsat + ΔT. And Tdis and Tdi
sx1 is compared, and when Tdis ≧ Tdisx1, it is determined that heating by the heater is unnecessary in the microcomputer 5c, and the heater is kept in the OFF state.
When s <Tdisx1, the microcomputer 5c issues a control command to the heater controller 14 to heat the liquid pool with a predetermined heating amount, and the heater 13a starts heating the liquid pool. As a result, the liquid refrigerant dissolved in the lubricating oil is vaporized into a superheated gas state and is sent out from the compressor 1. Therefore, as shown by the dotted line in FIG.
The two-phase state (point A) at the outlet of the compressed gas is heated by the heater 13a so as to be in the overheated gas state (point B), whereby the liquid refrigerant in the lubricating oil is vaporized and removed, and As a result, dilution of the lubricating oil with the liquid refrigerant can be avoided.

As described above, when the refrigerant state at the compressor discharge portion is detected and the refrigerant state is the two-phase state,
By directly heating the liquid pool in the compressor 1 by a heating means arranged so as to heat a liquid pool composed of a mixed phase of lubricating oil and liquid refrigerant, and vaporizing the liquid refrigerant dissolved in the lubricating oil, Even if a liquid refrigerant is generated due to condensation inside the compressor 1, it is possible to prevent the lubricating oil from being diluted with the liquid refrigerant, so that the viscosity of the lubricating oil inside the compressor 1 can be reduced more reliably with a simple configuration. Can be prevented.

Next, a sixth embodiment of the present invention will be described with reference to FIG.
This will be described using 9. FIG. 19 is a detailed view of an arrangement example of heating devices according to the sixth embodiment of the present invention. The difference from the fifth embodiment is that the heater 13b, which is the heating means, collects only the liquid pool near the suction port (oil suction port) of the oil pump that pumps up the lubricating oil for lubrication of the compression mechanism and sends it to the compression mechanism. The oil suction temperature lower limit value (from the temperature of the oil pump suction port (Tsuc), the thermistor 5f for measuring the temperature (Tsuc) of the oil pump, and the saturation temperature obtained from the compressor discharge pressure The point is to have a microcomputer 5g that determines Tsucx) and transmits a control signal. Here, unlike the fifth embodiment, the compressor discharge temperature (Tdis) measured by the thermistor 5a is not used for the control so that the heater 13b may heat a liquid pool in a limited range near the oil suction port. In order to reduce the size, the heating amount is not large, and therefore the heating amount may be such that the compressor discharge temperature hardly changes, and thus the thermistor 5a may be difficult to control. .

Next, a specific control method for solving the problem in the sixth embodiment of the present invention will be described with reference to FIG. Here, FIG. 20 is a control flowchart in the sixth embodiment of the present invention. In the figure, first, when the operation of the refrigeration system is started, Pdis and Tsuc are measured, then Tsat is calculated based on Pdis, and the compressor discharge temperature lower limit value is determined by Tsucx = Tsat + ΔT. Then, Tdis and Tsucx are compared, and Td
When is ≧ Tsucx, the heating by the heater 13b is controlled by the microcomputer 5g so as to be in an OFF state, but when Tsuc <Tsucx, the microcomputer 5g.
A control signal is issued to the heater controller 14 to start heating. As a result, it is possible to control so that the liquid refrigerant is vaporized and removed from the liquid pool at the oil suction port, that is, the lubricating oil is guided to the oil pump without being diluted with the liquid refrigerant.

As described above, when the liquid pool composed of the mixed phase of the lubricating oil and the liquid refrigerant is heated inside the compressor, the heating unit is directly heated by the heating unit. By disposing it near the suction port of the oil pump mechanism that pumps up the oil, the liquid refrigerant mixed with the lubricating oil that is about to be pumped up is specifically removed, and therefore the compressor 1 Even if liquid refrigerant is generated due to condensation inside, it is possible to more efficiently prevent the lubricating oil from being diluted with the liquid refrigerant. Moreover, since the heating means only needs to heat the liquid pool near the inlet of the oil pump mechanism, a smaller-scale heating means can be used, that is, a cheaper configuration, more effective and more reliable compression. It is possible to prevent the viscosity of the lubricating oil in the machine 1 from decreasing.

Next, a seventh embodiment of the present invention will be described with reference to FIG.
This will be described using 1. FIG. 21 is a detailed view of an arrangement example of heating devices according to the seventh embodiment of the present invention. The difference from the fifth and sixth embodiments is that the heater 13a or the heater 13b is arranged vertically above the oil suction port of the oil pump mechanism. In the sixth embodiment, when the heater 13b is disposed vertically below the oil suction port, the refrigerant gas heated by the heater 13b and vaporized moves upward,
It may lead to the oil pump mechanism trying to suck up the lubricating oil. In this case, the oil pump is in a gas biting state, and there is a possibility that the lubricating oil cannot be normally sent to each part of the compression mechanism. However, the heater 13
When b is arranged vertically above the oil suction port, the refrigerant gas heated by the heater 13b and vaporized becomes difficult to be sucked into the oil pump, so that the lubricating oil is sucked up as compared with the case where it is arranged vertically above. Can be done correctly and the lubrication is not compromised.

As described above, when heating the liquid pool composed of the mixed phase of the lubricating oil and the liquid refrigerant inside the compressor 1, the heating means is arranged vertically above the suction port of the oil pump mechanism for pumping the lubricating oil. By arranging it, it is possible to prevent the refrigerant gas heated and vaporized by the heating means from being sucked into the oil pump, suck up only the liquid lubricating oil, and reliably lubricate the compression mechanism with a simple structure. It will be possible to do.

Next, the eighth embodiment of the present invention will be described with reference to FIG.
Will be explained. FIG. 2 is a schematic diagram of the discharged refrigerant state detecting means according to the eighth embodiment of the present invention. As shown in the figure, the discharge refrigerant state detecting means of the present invention includes a thermistor 5a for measuring the temperature of the refrigerant at the compressor discharge, a pressure gauge 5b for measuring the compressor discharge pressure near the thermistor 5a, and a pressure gauge 5.
The saturated vapor temperature (Tsat) at the compressor discharge pressure is referred to or calculated based on the signal from b and compared with the temperature measured by the thermistor 5a to determine the lower limit value (Tdisx1) of the compressor discharge temperature. It comprises a microcomputer 5c that determines and issues a control command for the refrigeration system.

Next, a method of determining the compressor discharge temperature lower limit value in the present invention will be described with reference to FIG. FIG. 3 is a graph of a saturated vapor line approximation formula, in which the compressor discharge pressure (Pdis) measured by the pressure gauge 5b is compressed by the functional formula f (P) according to the refrigerant used as the working fluid. The machine discharge saturated vapor temperature (Tsat) is calculated. Note that Pd
Even if Tsat for is is given in the form of table in the microcomputer 5c, the same function is achieved. Here, in the microcomputer 5c, the compressor discharge temperature (Tdis) measured by the thermistor 5a is compared with Tsat in order to prevent the refrigerant state in the compressor discharge from being a two-phase state, which is the object of the present invention. The temperature difference (ΔT) to be taken is preset, and the compressor discharge temperature lower limit value Tdisx1 = Tsa
Calculated as t + ΔT. Now, if Tdis ≧ Tdisx1, it means that the refrigerant is not in the two-phase state at the discharge of the compressor, and conversely, if Tdis <Tdisx1, the refrigerant is at the two-phase state in the discharge of the compressor, and a control process for avoiding this state Will be determined to need.

Next, a specific control method applied when solving the problems as the eighth embodiment of the present invention will be described with reference to FIGS. 4 and 5. First, FIG. 4 is a control flowchart in the eighth embodiment of the present invention, and FIG. 5 is a Mollier diagram showing changes in the refrigeration cycle due to the control in the same embodiment. In FIG. 4, when the operation of the refrigeration system is started, Pdis and Tdis are measured first, and then Pdis
Tsat is calculated based on dis, and the compressor discharge temperature lower limit value is determined by Tdisx1 = Tsat + ΔT. Then, Tdis and Tdisx1 are compared, and Tdis ≧
If Tdisx1, the operating state is maintained as it is, but if Tdis <Tdisx1, the microcomputer 5
From c, a control command is issued to the condenser fan control microcomputer 6 so as to increase the number of rotations of the condenser fan unit 7 by one step. As a result, the condenser capacity increases as well as the evaporator capacity, allowing the compressor intake to draw in a drier or superheated refrigerant, and is therefore indicated by the dotted line in FIG. As described above, the refrigeration cycle in which the compressor discharge is in the two-phase state is changed to the refrigeration cycle in which the compressor discharge becomes the overheated gas state, and the generation of the liquid refrigerant in the compressor discharge part can be avoided.

As described above, as discharge refrigerant state detecting means, discharge temperature detecting means for detecting the refrigerant temperature at the compressor discharge, discharge pressure detecting means for detecting the refrigerant pressure at the compressor discharge, and the discharge By having the temperature detection means and the discharge temperature lower limit value determination means for determining the discharge temperature lower limit value based on the temperature and pressure detected by the discharge pressure detection means, it is common to other main body controls of the refrigeration system. It becomes possible to accurately detect the refrigerant state at the discharge of the compressor by using a usable sensor with a simple configuration and use it for controlling the refrigeration system.

Although the control object of the refrigerating apparatus is limited to the condenser fan unit in this embodiment, the present invention is not limited to the evaporator fan unit as in the second embodiment. Or in the case of an inverter as in the third embodiment, in the case of an electric expansion valve as in the fourth embodiment, or in the case of a heater as in the fifth and seventh embodiments. It is applicable to control.

Next, a ninth embodiment of the present invention will be described with reference to FIG.
2 is used for the explanation. FIG. 22 is a schematic view of the refrigerating apparatus according to the ninth embodiment of the present invention. The difference from the first to fifth embodiments is that the refrigerant state detection means has a thermistor 5a for detecting the compressor discharge temperature and a thermistor 5d for detecting the temperature of the refrigerant flowing through a specific position of the condenser 2. Further, based on the temperatures of the thermistor 5a and the thermistor 5d, a microcomputer 5e (discharge lower limit temperature determining means) for determining a compressor discharge temperature lower limit value (Tdisx2) so that the refrigerant in the compressor discharge does not become a two-phase state I have.

Next, a method of determining the compressor discharge temperature lower limit value in the present invention will be described with reference to FIG. FIG. 23 is a schematic diagram of a method for determining the compressor discharge temperature lower limit value. In the figure, ΔTx is a thermistor 5 preset by experiments or the like so that the refrigerant discharged from the compressor is not in a two-phase state.
It is the temperature difference between the compressor discharge temperature (Tdis) measured in a and the condenser temperature (Tcond) measured in the thermistor 5d. Tdisx2 = Tdisx2 = Tcond using Tdis and Tcond measured by the microcomputer 5e.
It shall be determined by the formula: cond + ΔTx.

Next, a specific control method for solving the problem in the ninth embodiment of the present invention will be described with reference to FIG. 24 together with the first embodiment. FIG. 24 shows the ninth aspect of the present invention.
3 is a control flowchart in the embodiment of FIG. In the figure, first, when the operation of the refrigeration system is started, Tdis and Tcond are measured, and then ΔTx prepared in advance is read out by the microcomputer 5e based on Tcond, and Tdisx2 is set as described above. Is determined. Then, Tdis and Tdisx2 are compared, and Tdis ≧ T
When disx2, the operating state is maintained as it is, but when Tdis <Tdisx2, the microcomputer 5e is used.
Then, a control command is issued to the evaporator fan control microcomputer 6 to increase the rotation speed of the evaporator fan unit 7 by one step. As a result, the capacity of the evaporator is increased, and it becomes possible to suck in a refrigerant having a higher degree of dryness or a superheated gas state in the suction of the compressor, and therefore, as in the first embodiment, it is shown by a dotted line in FIG. As described above, the refrigeration cycle in which the compressor discharge is in the two-phase state is changed to the refrigeration cycle in which the compressor discharge becomes the overheated gas state, and the generation of the liquid refrigerant in the compressor discharge part can be avoided. .

As described above, as the discharged refrigerant state detecting means, the discharge temperature detecting means for detecting the refrigerant temperature at the discharge of the compressor and the temperature of the refrigerant flowing through the specific portion on the pipe of the condenser 2 are detected. By using the condenser refrigerant temperature detecting means and the discharge temperature lower limit value determining means for determining the compressor discharge temperature lower limit value based on the temperature detected by the condenser refrigerant temperature detecting means, as compared with the temperature detecting means. It is easy to obtain without using a more expensive pressure measuring means. By predicting the refrigerant state at the compressor discharge using only the temperature detecting means that has been widely used from the past, it is cheaper and easier. The configuration makes it possible to estimate the refrigerant state at the compressor discharge.

Although the control target of the refrigerating apparatus is limited to the condenser fan unit in the present embodiment, the present invention is applied to the case where the control target is the condenser fan unit as in the first embodiment. Or in the case of an inverter as in the third embodiment, in the case of an electric expansion valve as in the fourth embodiment, or in the case of a heater as in the fifth and seventh embodiments. It is applicable to control.

[0057]

As is apparent from the above embodiments, the refrigerating apparatus of the present invention detects the refrigerant state in the compressor discharge portion, and when the refrigerant state is a two-phase state, the heat radiation fluid flow rate of the condenser is high. By increasing the flow rate of the heat-releasing fluid in the condenser by the control means, the condenser capacity is improved, and as a result, the evaporator capacity is also improved, and the compressor sucks the refrigerant in a higher dryness state. In this way, the refrigerant discharged from the compressor can be maintained as a superheated gas instead of a two-phase state. As described above, the refrigerant compressed and discharged by the compressor does not condense inside the compressor shell, and thus it is possible to prevent the viscosity of the lubricating oil in the compressor from lowering with a simple and inexpensive structure. .

Further, the refrigerating apparatus of the present invention detects the refrigerant state at the discharge portion of the compressor, and when the refrigerant state is a two-phase state, the heat-absorbed fluid flow rate control means of the evaporator absorbs heat to be absorbed by the evaporator. By increasing the flow rate of the fluid, the evaporator capacity is improved so that the compressor sucks the refrigerant in a higher dryness state, and the refrigerant at the discharge of the compressor becomes a superheated gas instead of a two-phase state. You will be able to keep up. Moreover, the control response is better than that in the case where the condenser capacity is improved, and the controllability for making the refrigerant in the compressor discharge into the superheated gas state can be further enhanced. As described above, the refrigerant compressed and discharged by the compressor will not condense inside the compressor shell,
Thus, it is possible to prevent the viscosity of the lubricating oil in the compressor from lowering with a simple and inexpensive structure.

Further, the refrigerating apparatus of the present invention detects the refrigerant state in the compressor discharge portion, and when the refrigerant state is a two-phase state, the operating capacity control means causes the compressor to operate at a higher capacity. By increasing the amount of refrigerant circulating in the refrigeration cycle, the capacity of the condenser and evaporator is improved, and as a result, the refrigerant in a higher dryness state is sucked in, and the refrigerant discharged at the compressor is It becomes possible to keep the superheated gas rather than the phase state. In addition, when the compressor operating capacity is controlled to correct the refrigeration cycle, there is an advantage that a wider range of refrigerating cycle capacity control can be expected as compared with the case where the heat exchange and heat absorption fluid flow rate control is performed by the heat exchanger. As described above, the refrigerant compressed / discharged by the compressor is prevented from condensing inside the compressor shell, so that the viscosity of the lubricating oil in the compressor can be more reliably prevented with a simple and inexpensive structure. It will be possible.

Further, the refrigerating apparatus of the present invention detects the refrigerant state at the compressor discharge portion, and when the refrigerant state is a two-phase state, the refrigerating apparatus controls the throttle amount in the variable capacity depressurizing apparatus to refrigerate. Control the amount of refrigerant circulation in the cycle so that the compressor sucks the refrigerant in a higher degree of dryness or in a superheated gas state so that the refrigerant at the compressor discharge becomes a superheated gas instead of a two-phase state Will be able to keep on.
Further, when the refrigeration cycle is corrected by controlling the throttle amount in the variable capacity decompression device, while having the same refrigeration cycle correction capacity as compared with the case of controlling the compressor operating capacity,
There is an advantage that the input to the refrigeration system accompanying the modification of the refrigeration cycle is reduced and a more efficient refrigeration cycle can be realized. As described above, the refrigerant compressed and discharged by the compressor is prevented from condensing inside the compressor shell, and thus with a simple and inexpensive structure, it is possible to more reliably prevent the viscosity of the lubricating oil in the compressor from lowering, Moreover, it becomes possible to realize a highly efficient refrigeration cycle.

Further, the refrigerating apparatus of the present invention detects the refrigerant state at the compressor discharge portion, and when the refrigerant state is a two-phase state, a liquid consisting of a mixed phase of lubricating oil and liquid refrigerant inside the compressor. By directly heating the liquid pool by the heating means arranged to heat the pool and vaporizing the liquid refrigerant dissolved in the lubricating oil, even if liquid refrigerant due to condensation is generated inside the compressor, lubrication is performed. It is possible to prevent the oil from being diluted with the liquid refrigerant, and thus it is possible to more reliably prevent the viscosity of the lubricating oil in the compressor from lowering with a simple configuration.

Further, the refrigerating apparatus of the present invention detects the refrigerant state at the discharge portion of the compressor, and when the refrigerant state is a two-phase state, a liquid consisting of a mixed phase of lubricating oil and liquid refrigerant inside the compressor. When heating the liquid pool directly by the heating means arranged to heat the pool, the heating means is arranged near the suction port of the oil pump mechanism for pumping the lubricating oil, so that Specially remove the liquid refrigerant that is mixed with the lubricating oil that is about to be removed, so that even if liquid refrigerant due to condensation occurs inside the compressor, it is possible to more efficiently prevent dilution of the lubricating oil with the liquid refrigerant. be able to. Moreover, since the heating means only needs to heat the liquid pool near the inlet of the oil pump mechanism, a smaller-scale heating means can be used, that is, with a cheaper configuration, the viscosity of the lubricating oil in the compressor can be more reliably achieved. It is possible to prevent the decrease.

Further, in the refrigerating apparatus of the present invention, as discharge refrigerant state detecting means, discharge temperature detecting means for detecting the refrigerant temperature at the compressor discharge, discharge pressure detecting means for detecting the refrigerant pressure at the compressor discharge, By having the discharge temperature detection means and the discharge temperature lower limit value determination means for determining the discharge temperature lower limit value based on the temperature and pressure detected by the discharge pressure detection means, the refrigerant state at the compressor discharge can be simplified. With such a configuration, it is possible to accurately detect and use it for controlling the refrigeration system.

Further, in the refrigerating apparatus of the present invention, as the discharged refrigerant state detecting means, the discharge temperature detecting means for detecting the refrigerant temperature at the discharge of the compressor and the temperature of the refrigerant flowing through a specific portion on the pipe of the condenser are detected. By using the condenser refrigerant temperature detecting means for, and the discharge temperature lower limit value determining means for determining the compressor discharge temperature lower limit value based on the temperature detected by the condenser refrigerant temperature detecting means, compared to the temperature detecting means. It is easy to obtain without using a more expensive pressure measuring means, and by predicting the refrigerant state at the compressor discharge by using only the temperature detecting means that has been widely used in the past, it is possible to use an inexpensive and simpler configuration. It becomes possible to estimate the refrigerant state at the discharge of the compressor.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a refrigeration system configuration according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of a discharged refrigerant state detecting means configuration according to first and eighth embodiments of the present invention.

FIG. 3 is a graph of a saturated vapor line approximation formula.

FIG. 4 is a control flowchart in the first and eighth embodiments of the present invention.

FIG. 5 is a Mollier diagram showing changes in the refrigeration cycle in the first and eighth embodiments of the present invention.

FIG. 6 is a schematic diagram of the configuration of a refrigeration system according to a second embodiment of the present invention.

FIG. 7 is a control flowchart in the second embodiment of the present invention.

FIG. 8 is a Mollier diagram showing changes in the refrigeration cycle in the second embodiment of the present invention.

FIG. 9 is a schematic diagram of the configuration of a refrigerating machine according to a third embodiment of the present invention.

FIG. 10 is a control flowchart in the third embodiment of the present invention.

FIG. 11 is a Mollier diagram showing changes in the refrigeration cycle in the third embodiment of the present invention.

FIG. 12 is a schematic diagram of the configuration of a refrigerating machine according to a fourth embodiment of the present invention.

FIG. 13 is a control flowchart in the fourth embodiment of the present invention.

FIG. 14 is a Mollier diagram showing changes in the refrigeration cycle in the fourth embodiment of the present invention.

FIG. 15 is a schematic diagram of the configuration of a refrigerating machine according to a fifth embodiment of the present invention.

FIG. 16: (1) Schematic diagram of compressor configuration (2) Detailed view of arrangement of heating device

FIG. 17 is a control flowchart in the fifth embodiment of the present invention.

FIG. 18 is a Mollier diagram showing changes in the refrigeration cycle in the fifth embodiment of the present invention.

FIG. 19 is a detailed view of a heating device arrangement example according to the sixth embodiment of the present invention.

FIG. 20 is a control flowchart in the sixth embodiment of the present invention.

FIG. 21 is a detailed view of an arrangement example of heating devices according to the seventh embodiment of the present invention.

FIG. 22 is a schematic diagram of the configuration of a refrigerating machine according to a ninth embodiment of the present invention.

FIG. 23 is a schematic diagram of a compressor discharge temperature lower limit value determination method according to a ninth embodiment of the present invention.

FIG. 24 is a control flowchart in the ninth embodiment of the present invention.

FIG. 25 is a schematic diagram of a configuration example of a conventional home air conditioner.

FIG. 26 is a Mollier diagram showing the refrigerant state.

[Explanation of symbols]

1 Compressor 2 Condenser 3 Expansion valve (pressure reducing device) 4 Evaporator 5 Refrigerant state detection device 5a Thermistor (compressor discharge temperature detection device) 5b Pressure gauge (compressor discharge pressure detection device) 5c Microcomputer (discharge using Pdis) Temperature lower limit value determination device) 5d Thermistor (compressor discharge temperature detection device) 5e Microcomputer (discharge temperature lower limit value determination device using Tcond) 5f Thermistor (oil suction temperature detection device) 5g Microcomputer (oil suction temperature lower limit value determination device) 6 Condenser fan control microcomputer (condenser heat release fluid flow rate control means) 7 Condenser fan unit 8 Evaporator fan control microcomputer (evaporator heat absorption fluid flow rate control means) 9 Evaporator fan unit 10 Inverter (compressor operation Capacity control means) 11 Electric expansion valve (capacity variable pressure reducing device) 12 Electric expansion valve control microcomputer (throttle Amount control means 13a Heater (heating means) 13b Small heater (heating means) 14 Heater controller (heating amount control means) 51 Compressor 52 Condenser 53 Expansion valve 54 Evaporator 55 Indoor air intake temperature measurement thermistor (thermistor) 56 Set temperature reading device (remote control) 57 Load determination device (microcomputer) 58 Compressor operating frequency control device (inverter)

Claims (9)

[Claims] 1. A discharge refrigerant state detecting means for detecting a refrigerant state in the compressor discharge part in a vapor compression refrigeration apparatus constituted by connecting a compressor, a condenser, a pressure reducing device and an evaporator with a refrigerant pipe. And a condenser radiating fluid flow rate control means for controlling the flow rate of the radiating fluid in the condenser according to the refrigerant state detected by the discharged refrigerant state detecting means. 2. A discharged refrigerant state detecting means for detecting a refrigerant state in the compressor discharge part in a vapor compression refrigeration apparatus constituted by connecting a compressor, a condenser, a pressure reducing device and an evaporator with a refrigerant pipe. And an evaporator heat-absorbed fluid flow rate control means for controlling the flow rate of the heat-absorbed fluid in the evaporator according to the refrigerant state detected by the discharged refrigerant state detection means. 3. In a vapor compression refrigeration system constituted by connecting a compressor, a condenser, a pressure reducing device, and an evaporator with a refrigerant pipe, a discharged refrigerant state detecting means for detecting a refrigerant state in the compressor discharge part. A refrigerating apparatus comprising: a refrigerating machine; and an operating capacity control means for controlling an operating capacity of the compressor according to a refrigerant state detected by the discharged refrigerant state detecting means. 4. A vapor compression refrigeration system configured by connecting a compressor, a condenser, a pressure reducing device (hereinafter, referred to as a variable capacity pressure reducing device) capable of changing the amount of throttle, and an evaporator through a refrigerant pipe, wherein: A discharge refrigerant state detection unit that detects a refrigerant state in the compressor discharge unit, and a throttle amount control unit that controls a throttle amount in the variable pressure reducing device according to the refrigerant state detected by the discharge refrigerant state detection unit. Characterizing refrigeration equipment. 5. A discharge refrigerant state detecting means for detecting a refrigerant state in the compressor discharge part in a vapor compression refrigeration apparatus constituted by connecting a compressor, a condenser, a pressure reducing device and an evaporator with a refrigerant pipe. A heating means arranged to heat a liquid pool composed of a mixed phase of lubricating oil and a liquid refrigerant inside the compressor; and heating by the heating means according to the refrigerant state detected by the discharged refrigerant state detecting means. A refrigerating apparatus comprising: a heating amount control means for controlling the amount. 6. The heating means is arranged near the suction port of an oil pump mechanism for pumping up the stored lubricating oil inside the compressor, and further detects the temperature of the suction port of the oil pump mechanism. The refrigeration system according to claim 5, further comprising an oil suction temperature detection means. 7. The heating means is arranged vertically above the suction port of an oil pump mechanism for pumping up the stored lubricating oil inside the compressor. The refrigeration system described. 8. A discharge temperature detecting means for detecting the refrigerant temperature at the compressor discharge, a discharge pressure detecting means for detecting the refrigerant pressure at the compressor discharge, and the discharge temperature detecting means as the discharge refrigerant state detecting means. 7. A discharge temperature lower limit value determining means for determining a discharge temperature lower limit value based on the temperature and pressure detected by the discharge pressure detecting means. Any of 7
Refrigerating apparatus according to paragraph. 9. A discharge refrigerant state detecting means for detecting a refrigerant temperature at the discharge of a compressor, and a condenser refrigerant temperature detecting means for detecting a temperature of a refrigerant flowing through a specific portion of the pipe of the condenser. 5. A discharge temperature lower limit value determining means for determining a compressor discharge temperature lower limit value based on the temperature detected by the condenser refrigerant temperature detecting means. The refrigerating apparatus according to any one of 5, 6, and 7.