JP2008215747A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner capable of improving energy consuming efficiency. <P>SOLUTION: This air conditioner is furnished with a compressor 1, a radiator 2, an expansion mechanism 3 and an evaporator 4. The compressor 1 compresses a refrigerant taken in from a suction side 11 and discharges it from a discharge side 12. The radiator 2 has an end 21 and the other end 22, and the one end 21 is connected to the discharge side 12 of the compressor 1. The evaporator 4 has one end 41 and the other end 42, and the one end 41 is connected to the suction side 11 of the compressor 1. The expansion mechanism 3 is connected between the other end 22 of the radiator 2 and the other end 42 of the evaporator 4. A ratio of rated heating capacity Q1 against compressor excluded volume E is more than 1.1 and less than 1.3 on such the air conditioner. Hereby, the rated heating capacity Q1 is calorie given to air in the radiator 2. The compressor excluded volume E is discharge of the refrigerant per one rotation of the compressor 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an air conditioner, and more particularly to an air conditioner using a refrigerant containing carbon dioxide as a main component.

  Conventionally, a water heater using a refrigerant containing carbon dioxide as a main component has been proposed. Such a water heater includes a compressor, a radiator, an expansion mechanism, and an evaporator. The refrigerant flows through the compressor, the radiator, the expansion mechanism, and the evaporator in this order. In the radiator, heat is transmitted from the refrigerant to the water for hot water supply, and the water is warmed.

  By the way, the air can be warmed by changing the object to be heat-exchanged with the refrigerant in the radiator from water for hot water supply to air. Therefore, an air conditioner using the hot water heater technology has been proposed.

In addition, the technique relevant to this invention is shown below.
Sugawara, “1. CO Heat Pump Water Heater 1.1 Development of CO2 Refrigerant Heat Pump Water Heater Applying Ejector Cycle”, Refrigeration, March 2004, Vol. 79, No. 917, p. 3-7

  However, if the conditions for operating the water heater, such as the compressor pressure, are applied to the air conditioner as they are, the efficiency of the air conditioner, particularly the energy consumption efficiency, may be reduced.

  This invention is made | formed in view of the situation mentioned above, and it aims at improving the energy consumption efficiency in an air conditioner.

An air conditioner according to a first invention includes a compressor, a radiator, an evaporator, and an expansion mechanism. The compressor compresses a refrigerant containing carbon dioxide as a main component. The radiator has one end connected to the discharge side of the compressor and the other end. The evaporator has one end connected to the suction side of the compressor and the other end. The expansion mechanism is connected between the other end of the radiator and the other end of the evaporator. The ratio of the amount of heat (unit: kW) given by the radiator to the air that exchanges heat with the refrigerant in the radiator to the refrigerant discharge amount (unit: cm ³ ) per rotation of the compressor is 1.1 or more. 1.3 or less.

An air conditioner according to a second invention includes a compressor, a radiator, an evaporator, and an expansion mechanism. The compressor compresses a refrigerant containing carbon dioxide as a main component. The radiator has one end connected to the discharge side of the compressor and the other end. The evaporator has one end connected to the suction side of the compressor and the other end. The expansion mechanism is connected between the other end of the radiator and the other end of the evaporator. The ratio of the amount of heat (unit: kW) obtained by the evaporator from the air that exchanges heat with the refrigerant in the evaporator to the amount of refrigerant discharged (unit: cm ³ ) per one rotation of the compressor is 0.6 or more 0.9 or less.

  An air conditioner according to a third aspect is the air conditioner according to the first or second aspect, wherein the pressure on the discharge side of the compressor is 8 (MPa) or more and 10 (MPa) or less.

  An air conditioner according to a fourth invention is the air conditioner according to any one of the first to third inventions, wherein the pressure on the suction side of the compressor is 2.5 (MPa) or more and 6.5 ( MPa) or less.

  An air conditioner according to a fifth invention is any one of the first to fourth inventions, and the compressor includes a motor. The motor has a stator and a rotor. The ratio of the length of the motor in the direction along the rotation axis of the rotor to the outer diameter of the stator is 0.8 or more.

  An air conditioner according to a sixth aspect of the present invention is the air conditioner according to any one of the first to fifth aspects, wherein the compressor includes a motor. The motor has a stator and a rotor. The ratio of the length of the motor in the direction along the rotation axis of the rotor to the outer diameter of the rotor is 1.4 or more.

  An air conditioner according to a seventh aspect is the air conditioner according to the fifth or sixth aspect, wherein the compressor further includes a crankshaft rotated by a motor. The ratio of the outer diameter of the crankshaft to the outer diameter of the rotor is 0.32 or more.

  According to the air conditioner of the first invention, since the ratio of the amount of heat to the discharge amount is small, even if the rated rotational speed of the compressor is small, a desired amount of heat can be given to the air in the radiator. Thus, a desired cooling or heating capability can be obtained in the air conditioner. Moreover, energy consumption efficiency (COP) in the air conditioner can be increased by reducing the rated rotational speed.

  According to the air conditioner of the second invention, since the ratio of the amount of heat to the discharge amount is small, a desired amount of heat can be obtained from the air in the evaporator even if the rated rotational speed of the compressor is small. Thus, a desired cooling or heating capability can be obtained in the air conditioner. Moreover, energy consumption efficiency (COP) in the air conditioner can be increased by reducing the rated rotational speed.

  According to the air conditioner pertaining to the third or fourth invention, the air conditioner can be operated more efficiently.

  According to the air conditioner pertaining to the fifth or sixth aspect of the invention, the motor output can be increased without increasing the diameter of the motor, thereby increasing the refrigerant discharge amount per rotation of the compressor. be able to. Therefore, the ratio of the amount of heat given to the air in the radiator to the amount discharged to the compressor can be reduced without increasing the diameter of the compressor.

  According to the air conditioner pertaining to the seventh aspect of the invention, even if the crankshaft is lengthened by increasing the length in the direction along the rotation axis of the motor, the crankshaft is not easily bent.

<Configuration of air conditioner>
FIG. 1 is a diagram conceptually showing an air conditioner according to an embodiment of the present invention. The air conditioner includes a compressor 1, a radiator 2, an expansion mechanism 3, and an evaporator 4. The compressor 1, the radiator 2, the expansion mechanism 3, and the evaporator 4 are annularly connected by a pipe 5 in this order. A refrigerant containing carbon dioxide as a main component flows in the direction of arrow 111 in the pipe 5. In other words, the refrigerant circulates through the compressor 1, the radiator 2, the expansion mechanism 3, and the evaporator 4 in this order.

  Specifically, the compressor 1 compresses the refrigerant sucked from the suction side 11 and discharges it from the discharge side 12. The radiator 2 has one end 21 and the other end 22, and the one end 21 is connected to the discharge side 12 of the compressor 1. The evaporator 4 has one end 41 and the other end 42, and the one end 41 is connected to the suction side 11 of the compressor 1. The expansion mechanism 3 is connected between the other end 22 of the radiator 2 and the other end 42 of the evaporator 4.

  FIG. 2 shows the state of the refrigerant contained as the main component of carbon dioxide in relation to enthalpy and pressure. Specifically, in FIG. 2, a critical point CP, a saturated vapor line 101, a saturated liquid line 102, and boundary lines 103 and 104 are shown. The saturated vapor line 101 indicates a boundary between a state in which a gas and a liquid are mixed (hereinafter referred to as “gas-liquid mixed state”) and a gas state. The saturated liquid line 102 indicates the boundary between the gas-liquid mixed state and the liquid state. The boundary line 103 is an isotherm passing through the critical point CP, and indicates a boundary between the liquid state and the supercritical state where the enthalpy is smaller than the critical point CP. The boundary line 104 is an isobaric line extending from the critical point CP to the larger enthalpy and indicates the boundary between the gas state and the supercritical state. Hereinafter, the state of the circulating refrigerant will be described with reference to FIG.

  The compressor 1 compresses the refrigerant in a gaseous state (state A) and transfers it to the supercritical state (state B). The refrigerant in the supercritical state can change its temperature and pressure without latent heat. Therefore, heat can be efficiently obtained from the refrigerant in the supercritical state.

  The radiator 2 transfers the heat of the refrigerant that has flowed into itself to the outside air, thereby reducing the enthalpy of the refrigerant with almost no change in pressure. Thereby, the radiator 2 transfers the refrigerant in the supercritical state (state B) to the liquid state (state C). At this time, a heat quantity Q substantially equal to the amount of change in enthalpy is given from the radiator 2 to the air. Since heat is efficiently obtained from the refrigerant in the supercritical state, the outside air can be efficiently warmed in the radiator 2.

  The expansion mechanism 3 changes the refrigerant in the liquid state (state C) to the gas-liquid mixed state (state D) by reducing the pressure of the refrigerant flowing from the radiator 2 side. At this time, the enthalpy of the refrigerant before and after passing through the expansion mechanism 3 hardly changes.

  The evaporator 4 increases the enthalpy of the refrigerant without changing the pressure by transferring heat from outside air to the refrigerant flowing into the evaporator 4. Thereby, the evaporator 4 transfers the refrigerant | coolant in a gas-liquid mixing state (state D) to a gaseous state (state A). At this time, most of the heat obtained from the outside air is used as latent heat to change the state of the refrigerant.

  According to the air conditioner described above, air can be harmonized efficiently. Specifically, air can be warmed in the radiator 2, and air can be cooled in the evaporator 4. Therefore, as shown in FIG. 1, when the radiator 2 is installed outdoors and the evaporator 4 is installed indoors, the air conditioner can function as a cooler.

  On the other hand, by installing the radiator 2 indoors and the evaporator 4 outdoors, the air conditioner can function as a heater.

  FIG. 3 conceptually shows an air conditioner that can perform both cooling and heating. The air conditioner includes a compressor 1, heat exchangers 61 and 62, an expansion mechanism 3, and a switching valve 8. Since the functions of the compressor 1 and the expansion mechanism 3 are the same as described above, description thereof is omitted.

  Both of the heat exchangers 61 and 62 exchange heat between external air and the refrigerant. Specifically, one of the heat exchangers 61 and 62 functions as the heat radiator 2 that transfers heat from the refrigerant to the outside air, and the other is the evaporator 4 that transfers heat from the outside air to the refrigerant. Function as. In FIG. 3, the heat exchanger 61 is set outdoors, and the heat exchanger 62 is set indoors.

  The switching valve 8 has terminals 81 to 84, communicates the terminal 81 and the terminal 84, and communicates the terminal 82 and the terminal 83, and communicates the terminal 81 and the terminal 82, And the aspect (mode b) which makes the terminal 83 and the terminal 84 communicate can be switched alternately.

  The terminal 81 is connected to the suction side 11 of the compressor 1. The terminal 82 is connected to one end 611 of the heat exchanger 61. The terminal 83 is connected to the discharge side 12 of the compressor 1. The terminal 84 is connected to one end 621 of the heat exchanger 62.

  The expansion mechanism 3 is connected between the other end 612 of the heat exchanger 61 and the other end 622 of the heat exchanger 62.

  According to this air conditioner, by switching the switching valve 8 to the mode a, the refrigerant flows in the direction of the arrow 111, the heat exchanger 61 functions as the radiator 2, and the heat exchanger 62 serves as the evaporator 4. Can function. That is, the air conditioner functions as a cooling device.

  On the other hand, by switching the switching valve 8 to the mode b, the refrigerant flows in the direction of the arrow 112, so that the heat exchanger 61 can function as the evaporator 4 and the heat exchanger 62 can function as the radiator 2. That is, the air conditioner can function as a heater.

<Conditions for operating the air conditioner>
FIG. 4 shows the conditions for operating the air conditioner and the energy consumption efficiency (COP) when operating under those conditions. In FIG. 4, the system high pressure P1 (MPa), the system low pressure P2 (MPa), the compression ratio P1 / P2, the rated heating capacity Q1 (kW), the compressor displacement volume E (cm ³ / rev), and the ratio Q1 Each value of / E is shown in four ways (conditions 1 to 4).

  Here, the system high pressure P1 is the pressure on the discharge side 12 of the compressor 1, and is the pressure of the refrigerant in the state B (FIG. 2). The system low pressure P2 is the pressure on the suction side 11 of the compressor 1 and is the pressure of the refrigerant in the state A (FIG. 2). The compression ratio P1 / P2 is a ratio of the pressure P1 to the pressure P2. The rated heating capacity Q1 is the amount of heat given to the air in the radiator 2. The compressor rejection volume E is the refrigerant discharge amount per rotation of the compressor 1. The ratio Q1 / E is a ratio between the rated heating capacity Q1 and the compression exclusion volume E.

  In FIG. 4, the conditions suitable for the operation | movement of the air conditioner mentioned above are illustrated in the conditions 4, and are compared with the conditions 1-3.

Conditions 1 and 2 exemplify conditions suitable for operating a water heater having the same configuration as the air conditioner described above. That is, in condition 1, the system high pressure P1 is 12.0 (MPa), the system low pressure P2 is 4.0 (MPa), the compression ratio P1 / P2 is 3.0, the rated heating capacity Q1 is 6.0 (kW), The compressor rejection volume E is 4.5 (cm ³ / rev), and the ratio Q1 / E is 1.33. At this time, the system COP of the water heater is 4.17. In condition 2, the system high pressure P1 is 12.0 (MPa), the system low pressure P2 is 4.0 (MPa), the compression ratio P1 / P2 is 3.0, the rated heating capacity Q1 is 4.5 (kW), and the compressor The excluded volume E is 3.3 (cm ³ / rev), and the ratio Q1 / E is 1.36. At this time, the system COP of the water heater is 3.46.

  Conditions 1 and 2 are both set in a predetermined environment and a desired water temperature. Specifically, the dry bulb temperature (DB) and wet bulb temperature (WB) at the position where the water heater is installed are 16 (° C.) and 12 (° C.), respectively, and the water temperature is 17 (° C.). When the temperature is increased from 65 to 65 (° C.), conditions 1 and 2 are set.

Condition 3 is a condition used experimentally when operating the air conditioner, and a larger value than the ratio Q1 / E of the conditions 1 and 2 is adopted as the ratio Q1 / E. Specifically, system high pressure P1 is 10.0 (MPa), system low pressure P2 is 4.5 (MPa), compression ratio P1 / P2 is 2.2, rated heating capacity Q1 is 20.0 (kW), compression The machine exclusion volume E is 12.1 (cm ³ / rev), and the ratio Q1 / E is 1.65.

  The condition 3 is set in a predetermined environment and a desired room temperature. Specifically, when the dry-bulb temperature (DB) of outdoor air and the wet-bulb temperature (WB) are 35 (° C.) and 24 (° C.), respectively, ) And are set to condition 3 when the wet bulb temperature (WB) is set to 27 (° C.) and 19 (° C.), respectively. The same applies to condition 4, and the same applies to conditions 5 and 6 (FIG. 7) described later.

  By the way, in the air conditioner, the system high pressure P1 is 8 (MPa) or more and 10 (MPa) or less, and the system low pressure P2 is 2.5 (MPa) or more and 6.5 (MPa) or less. It is desirable in that the operation efficiency of the machine can be increased. Therefore, in condition 3, 10.0 (MPa) is adopted for the system high pressure P1 and 4.5 (MPa) is adopted for the system low pressure P2. The same applies to condition 4, and the same applies to condition 5 and condition 6 (FIG. 7) described later.

  When the air conditioner is operated under condition 3, the system COP of the air conditioner is 3.57 (FIG. 4), and it can be seen that the system COP is lower than that of the water heater operated under condition 1.

On the other hand, in the condition 4, the ratio Q / E is 1.15 by setting the rated heating capacity Q1 to 19.0 (kW) and the compressor displacement volume E to 16.5 (cm ³ / rev) in the condition 3. Yes. That is, a smaller value than the ratio Q1 / E of condition 1 and condition 2 is adopted as the ratio Q1 / E of condition 4.

  Under the condition 4, the system COP of the air conditioner is 3.80, which is larger than the system COP when the air conditioner is operated under the condition 3. Hereinafter, the reason will be described.

  FIG. 5 is a graph showing the relationship between the rotational speed and the efficiency of the compressor 1 when the compression ratio P1 / P2 is 3.0 (condition 1 or condition 2 which is the condition of the water heater). FIG. 6 is a graph showing the relationship between the rotational speed and the efficiency of the compressor 1 when the compression ratio P1 / P2 is 2.2 (condition 3 or condition 4 which is the condition of the air conditioner).

  In FIG. 5, the efficiency of the compressor 1 hardly decreases even when the rotational speed increases. On the other hand, in FIG. 6, as the rotational speed increases, the efficiency of the compressor 1 decreases.

  By the way, when the ratio Q1 / E is large, it is necessary to increase the rotational speed in order to obtain a desired cooling or heating capability in the air conditioner. On the other hand, when the ratio Q1 / E is small, the rotational speed may be small in order to obtain the capability in the air conditioner.

  Specifically, when the ratio Q1 / E is 1.65 (condition 3), the rotational speed for obtaining a desired cooling or heating capability in the air conditioner, that is, the rated rotational speed is 80 to 90 ( rps). On the other hand, when the ratio Q1 / E is 1.15 (condition 4), the rated rotational speed is 60 to 70 (rps).

  If the compression ratio P1 / P2 is 3.0 as in Condition 1 or Condition 2, efficiency of about 70% can be obtained in the compressor 1 even if the rated speed is 80 to 90 (rps). (FIG. 5). However, when the compression ratio P1 / P2 is 2.2 as in the condition 3 and the rated rotational speed is 80 to 90 (rps), only an efficiency of about 65 (%) can be obtained in the compressor 1 ( FIG. 6).

  Even if the compression ratio P1 / P2 is 2.2 by reducing the ratio Q1 / E as in condition 4 and reducing the rated rotational speed to 60 to 70 (rps), the compressor 1 The efficiency can be increased to 70 (%) or more (FIG. 6). Therefore, the air conditioner system COP also increases.

  From the viewpoint of reducing the rated rotational speed by reducing the ratio Q1 / E, the ratio Q1 / E is desirably 1.3 or less. By reducing the ratio Q1 / E, the rated rotational speed is reduced, but if it is too small, the efficiency of the compressor 1 may be reduced. Therefore, the ratio Q1 / E is desirably 1.1 or more.

  The conditions for operating the air conditioner may be set using the rated heating capacity Q2 which is the amount of heat obtained from the air in the evaporator 4 instead of the rated heating capacity Q1. This will be specifically described with reference to FIG.

In FIG. 7, the system high pressure P1 (MPa), the system low pressure P2 (MPa), the compression ratio P1 / P2, the rated heating capacity Q2 (kW), the compressor displacement volume E (cm ³ / rev), and the ratio are shown as conditions. Each value of Q2 / E is shown in two ways (Condition 5 and Condition 6).

Condition 5 is a condition used experimentally when operating the air conditioner. Specifically, the rated heating capacity Q2 is 14.0 (kW), the compressor rejection volume E is 11.1 (cm ³ / rev), and the ratio Q2 / E is 1.26. The system high pressure P1 and the system low pressure P2 have the same values as the conditions 3 and 4, respectively, and the conditions 6 are the same.

  When the ratio Q2 / E is 1.26, the rated rotational speed is 80 to 90 (rps), and the compressor 1 can only achieve an efficiency of about 65% (FIG. 6).

On the other hand, in the condition 6, the ratio Q2 / E is set to 0.85 by setting the rated heating capacity Q2 to 14.0 (kW) and the compressor rejection volume E to 16.5 (cm ³ / rev) in the condition 5. Yes.

  When the ratio Q2 / E is 0.85, the rated rotational speed is 60 to 70 (rps), and the compressor 1 can obtain an efficiency of 70 (%) or more (FIG. 6).

  From the above, the efficiency of the compressor 1 can be increased by reducing the ratio Q2 / E. Therefore, the system COP of the air conditioner can be increased.

  From the viewpoint of reducing the rated rotational speed by reducing the ratio Q2 / E, the ratio Q2 / E is desirably 0.9 or less. By reducing the ratio Q2 / E, the rated rotational speed is reduced, but if it is too small, the efficiency of the compressor 1 may be reduced. Therefore, the ratio Q2 / E is desirably 0.6 or more.

<Configuration of compressor 1>
FIG. 8 is a sectional view conceptually showing the compressor 1. The compressor 1 includes a motor 7, a crankshaft 74, a bearing 75, and a compression chamber 76. The motor 7 has a stator 71 and a rotor 72. The crankshaft 74 extends along the rotation shaft 73 of the rotor 72, one end thereof is connected to the rotor 72, and the other end is rotatably supported by the bearing 75.

  The refrigerant is sucked into the compression chamber 76 from the suction side 11 of the compressor 1. The refrigerant in the compression chamber 76 is compressed by the rotation of the crankshaft 74 and is discharged from the discharge side 12 of the compressor 1.

  The ratio L / r1 of the length L of the motor 7 in the direction 91 along the rotation shaft 73 to the outer diameter r1 of the stator 71 is desirably 0.8 or more. This is because the motor output can be increased by increasing the length L of the motor 7 without increasing the diameter of the motor 7, and the compressor displacement volume E can be increased. In other words, the ratio Q / E can be reduced without increasing the diameter of the compressor 1.

  From the viewpoint of reducing the ratio Q / E without increasing the diameter of the compressor 1, the ratio L / r2 of the length L of the motor 7 to the outer diameter r2 of the rotor 72 is set to 1.4 or more. May be.

  When the length L of the motor 7 is increased, the crankshaft 74 becomes longer along the rotation shaft 73, so that the crankshaft 74 is easily bent. In order to reduce the bending of the crankshaft 74, it is desirable that the ratio r3 / r2 of the outer diameter r3 of the crankshaft 74 to the outer diameter r2 of the rotor 72 be 0.32 or more.

FIG. 9 illustrates the dimensions of the motor 7 in the condition F3 for the compressor 1 used in the air conditioner. In FIG. 9, the inner diameter (hereinafter referred to as “pipe inner diameter”) (mm) and cylinder volume (cm ³ / rev) of the compressor 1, the maximum torque (N · m) and the length L ( mm), the outer diameter r1 (mm) of the stator 71, the outer diameter r2 (mm) of the rotor 72, the outer diameter r3 (mm) of the crankshaft 74, and the ratios L / r1, L / r2, and r3 / r2. Each value is shown. Since the stator 71 is fixed in the pipe 15 by press-fitting, for example, the inner diameter of the pipe 15 and the outer diameter of the stator 71 are substantially equal.

Under condition 3F, the inner diameter of the pipe is 125 (mm), the cylinder volume is 16.5 (cm ³ / rev), the maximum torque of the motor 7 is 18 (N · m), the length L is 110 (mm), and the outer diameter r1 Is 125 (mm), the outer diameter r2 is 65 (mm), and the outer diameter r3 is 22 (mm). The ratio L / r1 is 0.88, the ratio L / r2 is 1.69, and the ratio r3 / r2 is 0.34.

  In FIG. 9, for comparison with the condition F3, dimensions and the like related to the compressor 1 used in the water heater are also shown in the condition F1 and the condition F2, respectively.

In condition F1, the inner diameter of the pipe is 112 (mm), the cylinder volume is 4.2 (cm ³ / rev), the maximum torque of the motor 7 is 6 (N · m), the length L is 70 (mm), and the outer diameter r1 Is 112 (mm), the outer diameter r2 is 55 (mm), and the outer diameter r3 is 16 (mm). The ratio L / r1 is 0.625, the ratio L / r2 is 1.27, and the ratio r3 / r2 is 0.29.

In condition F2, the inner diameter of the pipe is 125 (mm), the cylinder volume is 11.1 (cm ³ / rev), the maximum torque of the motor 7 is 15 (N · m), the length L is 90 (mm), and the outer diameter r1 Is 125 (mm), the outer diameter r2 is 65 (mm), and the outer diameter r3 is 20 (mm). The ratio L / r1 is 0.72, the ratio L / r2 is 1.38, and the ratio r3 / r2 is 0.31.

It is a figure which shows notionally the air conditioner concerning embodiment of this invention. It is a figure which shows the state of a refrigerant | coolant by the relationship between enthalpy and pressure. It is a figure which shows notionally the air conditioner which can perform both air_conditioning | cooling and heating. It is a figure which shows the conditions at the time of driving | running an air conditioner, and energy COP. It is a figure which shows the relationship between a rotation speed and the efficiency of the compressor 1 with a graph. It is a figure which shows the relationship between a rotation speed and the efficiency of the compressor 1 with a graph. It is a figure which shows the conditions at the time of driving | running an air conditioner. 1 is a cross-sectional view conceptually showing a compressor 1. It is a figure which shows the dimension of the motor 7, etc. about the compressor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Radiator 3 Expansion mechanism 4 Evaporator 7 Motor 11 Suction side 12 Discharge side 21, 41 One end 22, 42 Other end 71 Stator 72 Rotor 73 Rotating shaft 74 Crankshaft 91 Direction 741 Partial Q1, Q2 Rated heating Ability (calorie)
E Excluded compressor capacity (discharge amount)
P1 System high pressure (pressure on the discharge side)
P2 system low pressure (pressure on suction side)
L length r1, r2, r3 outer diameter

Claims (7)

A compressor (1) for compressing a refrigerant containing carbon dioxide as a main component;
A radiator (2) having one end (21) connected to the discharge side (12) of the compressor and the other end (22);
An evaporator (4) having one end (41) connected to the suction side (11) of the compressor and the other end (42);
An expansion mechanism (3) connected between the other end of the radiator and the other end of the evaporator;
The amount of heat (Q1) (unit is kW) given by the radiator to the air that exchanges heat with the refrigerant in the radiator, and the discharge amount (E) of the refrigerant per rotation of the compressor (unit: cm ³ ), an air conditioner having a ratio (Q1 / E) of 1.1 or more and 1.3 or less. A compressor (1) for compressing a refrigerant containing carbon dioxide as a main component;
A radiator (2) having one end (21) connected to the discharge side (12) of the compressor and the other end (22);
An evaporator (4) having one end (41) connected to the suction side (11) of the compressor and the other end (42);
An expansion mechanism (3) connected between the other end of the radiator and the other end of the evaporator;
The amount of heat (Q2) (unit: kW) that the evaporator obtains from the air that exchanges heat with the refrigerant in the evaporator, the discharge amount (E) of the refrigerant per revolution of the compressor (unit: cm ³ ) (Q2 / E) is an air conditioner having a ratio of 0.6 to 0.9.   The air conditioner according to claim 1 or 2, wherein a pressure (P1) on the discharge side (12) of the compressor (1) is 8 (MPa) or more and 10 (MPa) or less.   The pressure (P2) on the suction side (11) of the compressor (1) is not less than 2.5 (MPa) and not more than 6.5 (MPa). The air conditioner described. The compressor (1) includes a motor (7) having a stator (71) and a rotor (72),
The ratio (L / r1) of the motor length (L) to the outer diameter (r1) of the stator in the direction (91) along the rotation axis (73) of the rotor is 0.8 or more. The air conditioner according to any one of claims 1 to 4. The compressor (1) includes a motor (7) having a stator (71) and a rotor (72),
The ratio (L / r2) of the motor length (L) to the outer diameter (r2) of the rotor in the direction (91) along the rotation axis (73) of the rotor is 1.4 or more. The air conditioner according to any one of claims 1 to 5. The compressor (1) further comprises a crankshaft (74) rotated by the motor (7),
The air conditioner according to claim 5 or 6, wherein a ratio (r3 / r2) of the outer diameter (r3) of the crankshaft to the outer diameter (r2) of the rotor is 0.32 or more.

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