JPS5864437A - Control on refrigerating cycle - Google Patents

Abstract

PURPOSE:To reduce the consumption of power as well as raise a feeling of air conditioning by a method in which the discharge capacity of a compressor is stepwise controlled according to the sensing signals of the temperatures of air blown out and of a room and set values for preventing frosting on a vaporizer are altered according to the magnitude of the discharge capacity. CONSTITUTION:In a compressor 12 incorporated with a capacity-varying device 18, in which the driving of the capacity-varying device is controlled by controlling a solenoid valve 16, the solenoid valve 16 is controlled by a control circuit on the basis of the signals of temperature sensors 14 and 19 consisting of thermisters to detect the temperatures of air right behind the vaporizer 5 and also of the chamber of an auto car. In short, when the temperature of auto car's chamber is higher than a set value, the solenoid valve 16 is closed, the discharge capacity of the compressor 12 is set up to a great capacity (100%), and the set value of the temperature of air blown out of the vaporizer is lowered. On the other hand, in the reverse case, the solenoid valve 16 is opened, the discharge capacity of the compressor 12 is set up to a small capacity (30-50%), and the set value of air blown out is raised.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the capacity of a refrigeration cycle used for air conditioning of automobiles.

A conventionally well-known 7-position refrigeration cycle for automobile air conditioners is composed of a compressor 1, a condenser 2, a V7 valve 3, an expansion valve 4, and an evaporator 5, as shown in FIG. Since it is driven by an automobile engine (not shown) via the electromagnetic clutch 7, the compressor rotation speed increases as the engine speed increases. Therefore, pressure @
When the rotational speed of the machine 1 increases or the cooling load decreases due to a drop in outside temperature, etc., the fin temperature of the evaporator 5, that is, the evaporation temperature of the refrigerant, decreases below 0°C, causing the fin Kl to decrease. may adhere or freeze, the amount of air blown by the blower 8 decreases, and the cooling capacity decreases. In order to prevent the rounding and the appearance of wear and tear, and to control the temperature inside the vehicle, the air temperature after the evaporator 51 is measured using a temperature sensor such as a thermistor.
Detected at 6, $2 Control shown in figure 1 Relay 1 at Kawaji Town
By opening and closing the contacts 10 & of to control the air temperature.

By the way, in such a configuration, the cooling load has decreased.9
If the rotational speed of the compressor 1 increases, the compressor's compressor function becomes excessive, and the capacity of the refrigeration cycle exceeds the cooling load.

However, in the conventional system, regardless of the size of the cooling load, the compression unit 11 always operates intermittently at the maximum capacity of V, so the drive load of the drive source of the engine unit 1 is always at the maximum, resulting in large power consumption. There is a problem that the @ sound also gets louder.

The present invention has been made in view of the above-mentioned problems, and uses a variable volume type that has a built-in variable member to change the discharge temperature of the compressor in stages, and changes the air blowing temperature immediately after the evaporator or Sensing the refrigerant temperature and refrigerant pressure in the evaporator, as well as sensing the room temperature or suction air temperature of the room temperature to be air-conditioned, and controlling the discharge capacity of the compressor in stages according to both sensing signals, and
The setting value of the evaporator frost prevention is changed according to the discharge capacity, and the temperature fluctuation of the blown air that directly hits the occupants is alleviated, giving a good air conditioning feeling, and the refrigeration cycle is adjusted to the capacity according to the load at that time. The object of the present invention is to provide a refrigeration cycle control method that can improve the cooling capacity and reliably prevent the compressor from frosting, and can also reduce the power consumption and noise of the compressor. shall be.

Embodiments of the present invention will be described below.

Since the freezing cycle in the method of the present invention may be the same as that shown in FIG. 1, the explanation will be based on warming. #I: Figure 8 shows the method of the present invention, in which the evaporator 5 and motor-driven air blower 118 shown in Figure 1 are provided. The left end side of the ventilation casing 11 communicates with an inside air suction port and an outside air suction port via an inside/outside air switching ellipse (not shown), and the right end side communicates with an inside air inlet and an outside air inlet through a heater unit (not shown), and an air outlet (upper air outlet for air conditioning, It communicates with the lower air outlet for Enokibo, etc.). A compressor 12 is connected to the cooling V& circuit on the outlet side of the evaporator fi5, and this pressure @1Ji12 is driven by the automobile engine via a tffl clutch 18. Further, this pressure wI 412 is configured as a variable capacity type having a built-in capacity variable member 18 for varying the discharge capacity, as will be described later.

14 is a temperature sensor consisting of a thermistor for sensing the temperature of the air 4X immediately after the evaporator; 19 is a temperature sensor consisting of a thermistor for sensing the representative negative temperature inside the air conditioner; 15 is a temperature sensor consisting of the same. A control circuit 16 which receives the signal from the temperature sensor 1419 is a round electromagnetic valve that drives the variable capacity member 18 in the compressor 12, and is controlled by the output of the control circuit 15. 21 is the activation switch of the empty m device;
22 is an ignition switch, and 28 is an in-vehicle power supply.

FIG. 4 shows a specific example of the control circuit 15, in which the comparator 81 has a potential 1 determined by the resistance value of the resistor 82 and the thermistor resistance +XR1 of the evaporation EASO blowout temperature sensor 14, and the resistor 88. .841+2@1! t
The comparator output Sta is determined from the reference potential v2 determined by 4IiK and K. Transistor 86 = amplifier output 8! A relay 86 is controlled by turning on and off the transistors 85 of Hatanyopuon, Offshi, and Ko. Then, by opening and closing the contacts 86 & of the relay 86, the latch 1 becomes stained.
Intermittent 4 electricity of 8.

The comparator 87 has a potential v3 determined by the resistance value of the resistor 88 and the thermistor resistance value of the room temperature sensor 19.
The output 87 & is determined by the reference potential v4 determined by the resistance value of the resistor 89, 40, 4 (l).The transistor 41 is turned on and off by the comparator output 87M,
A relay 42 is controlled by turning on and off this transistor 41. The energization of the solenoid valve 16 is interrupted by opening and closing the contacts 42& of the relay 42. Also, is transistor 41 on? When the transistor 48 is on, the resistor 44 is connected in parallel to the reference potential setting resistor 84 of the compass 81, and a new reference potential' (vz <"'z) is set. The guest alarm detector 14.19 is a load type thermistor whose resistance value decreases as the temperature rises, and the relationship between the change in the thermistor resistance value R1% and the comparator outputs 81j and 878 is shown in Figure 6 ( &), and are set as shown in (b).

When the 1/-fi output 87a is at the 'H1' level, the transistor 4 is turned on and the transistor 48 is turned off, so the reference potential of the comparator 81 becomes vl, which is greater than v8°.In this case, In Figure 6(a),
II! As shown by the line, comparator output 11m indicates that the temperature of the blowing air immediately after the evaporator increases (for example, from 1°0) to R1.
When the voltage 4 decreases below 4m, the level becomes "Hl", the transistor 86 is turned on, the relay 86 is activated, and the normally open contact 86eL is closed. As a result, the electromagnetic clutch 18 is activated and the compressor 12 is activated. Conversely, if the blowing air temperature is, for example, 0”
When RI4 decreases from RsaB and increases from RsaB, “L,
° level. This is K], the transistor 86 is turned off, energization to the relay ss is stopped, and the contact 86m returns to the open state 11.The electromagnetic clutch 18 is disconnected and the compression Il is turned off.
l The snow stops. t2 combo p output s7m is 1-”
When the level is high, the transistor 41 is turned off and the relay 4
! does not operate, normally closed contact 4! ! When the valve is closed, the electromagnetic pulp 16 is activated. Further, when the F run raster 41 is turned off, the base voltage is applied to the transistor 48, the transistor 48 is turned on, and the resistor 44 is connected in parallel to the reference potential setting resistor 84 of the comparator 81, so that the reference potential of the comparator 11 is set to -1, which is smaller than 1. change to °. For this reason.

The comparator output 81g is switched and controlled so as to move to the high temperature side as shown by the dotted line in the middle of FIG. 5(a).

The comparator output 87 becomes the "Ill" level when the room temperature rises by, for example, 26°C and R1, decreases by RBA, and conversely, when the room temperature falls below, for example, 24°C, El,
When increases by R1·B, it becomes "L", a level.

Next, an example of a specific configuration of the compressor 12 will be described.

In FIG. 6, 100 is a cylindrical rotor, and 101 is a vane slidably inserted in the radial direction into a slit 102 provided in the rotor lOO. Although only two vanes are shown in FIG. In reality, there are four pieces arranged at equal intervals. 108
104.10S is a cylindrical cylinder that regulates the reciprocating movement of the vane 101 in the radial direction, and 104.10S is a front side plate and a rear side plate that sandwich both ends of the cylinder 1030 through microscopic air communication with the W-100 and the vane 101. . And these rotor 100, vane 101
．． cylinder 10g and front side play) 104.
Rear side plate 10! A working space V is formed by S.

Also, cylinder ios, front side plate 104
．． The rear side plate 105 is connected to the housing 106.10
The tightening is fixed by port 108 together with 7. The rotor 100 is integrally connected to the rotating shaft 10g, and the rotating shaft 109 is connected to the front side plate 104 by a bearing 110. The rear side plate 1 (IK rotationally supported and receives driving force from the automobile engine via an electromagnetic clutch 18 etc.) 111 is a shaft sealing device that maintains a seal with the outside air.

Then, the 74-inch F side plate 104 and the housing 1
Intake 1ir1111 is formed by 08.

Frozen Nital's evaporator 5 and this inhalation! The refrigerant sucked into the front side play 112 is drawn into the suction port 11g (FIG. 8) opened in the front side play 104 into the V during nighttime operation. That is, the working nitrogen gap V is filled with refrigerant at suction pressure (as shown in FIG. 8(a)). The refrigerant sucked into the working space V is compressed as the volume of the working space V decreases.

In the most compressed state, it is discharged from the discharge port 114 of the cylinder 10g through a discharge valve (not shown), etc., to the discharge port 107a in the I-Ujifugu 10f, and then to the condenser 2 of the refrigeration cycle. Ru.

P is the shade for unloading, front side plate 1
04 and communicates the working space V with the suction chamber 112. Therefore, in the state where the unloading pipe P) is open, the refrigerant will not be compressed until the working space V separates from the communication pipe with the unloading pipe P. Mashi.

The space volume v1 at the start of compression in the open state 1iK of this unloading/-)P is shown in FIG. The spatial volume V・ is 0 in this example shown in FIG. 8 (&).
The unloading port P is opened at a position such that V is approximately sO% to 60%.

11M is an on-off valve that opens and closes the unloading mate P. To specifically explain the structure of this on-off valve 115, the seventh
As shown in the figure, a valve body 111i and a spring 11 bias the valve body 115al with a predetermined load in the opening direction.
51), the valve body 115a, and the t-driven bellow flamm 1
15c, and a plate 116f that also serves as a spring seat and guides the bellow frame 115c4. In addition, the valve body 115a
is made of high-strength material such as stainless steel. And, the chamber 116d on the back side of the bellows 7 ram 115C has a viroft pressure introduction port v! &l 17 are in communication with each other, and the pilot pressure, that is, suction pressure or discharge pressure, is applied by controlling the solenoid valve 160.

11? The IL is formed in the biloft pressure introduction passage 117 and has a nine-way restriction to prevent the pilot pressure from being suddenly applied to g 1154. On the other hand, Bellow 7 rum 1l
The pressure of the suction chamber 112 is applied to the li 115 s on the surface side of the lia.

By the combination of the above-mentioned yt/-)P and the on-off valve 115,
A variable capacitance member 18 is configured.

The driving of the on-off valve 115 of the BO) P is controlled by a solenoid valve 16.

As shown in FIG. 9, the electromagnetic valve 16 has eight pressure ports, namely, a suction pressure inlet 16&, a discharge pressure inlet 16b, and a pilot pressure outlet 1110. ! The pressure of the discharge pressure inlet l5it) is the discharge pressure 1i[107! The virofloft pressure outlet 16o communicates with the chamber on the valve body closing side of the on-off valve 11B, that is, the pilot valve 11Jsll. And solenoid valve 16
The pilot pressure outlet 16o4C is ':1ile 16
The position of the valve body 168 made of magnetic material is controlled by intermittent energization to d.

Suction pressure or discharge pressure is selected and applied respectively.

Therefore, when suction pressure is introduced to the viroft pressure outlet lea, the pilot) 11116a increases to the suction pressure,
Therefore, the valve body 116a moves in the opening direction by the setting force of the spring 11B'b, and the on-off valve 11B opens the port P. Conversely, when the discharge pressure is introduced into the pilot pressure outlet 18a, the valve body 115a moves in the closing direction against the setting force of the spring 116b. The moving on-off valve 116 closes the boat P.

The solenoid valve 16 is used to prevent malfunction due to overheating.The solenoid valve 16 is used to prevent malfunction due to overheating.The parts 1 of the compressor 12 that are relatively low temperature, such as the service nozzle (not shown) through which the suction refrigerant passes, and the front nozzle 106 is located adjacent to.

Next, the operation of the control method according to this embodiment will be explained.

t11 temperature is higher than 16°C! When the thermistor resistance value R1 of the frequency detector ill is smaller than RII, the comparator output 3 to 6 becomes "H1 level. This turns on the transistor 41, and the normally closed contact 4 of the relay 4 opens. Therefore, the solenoid valve 16 is in the state shown in FIG. 9, and since the valve body 16 and the whirling discharge pressure introduction hole 11111 are open, the valve body 1158 of the on-off valve 115 is not energized by the discharge pressure. The discharge capacity of the compressor 12 is increased to a large capacity (
100% capacity). In this case, since the transistor 41 is on, no base voltage is applied to the transistor 48, and the transistor 48 is turned off.

Therefore, the resistor 44 does not act, and the set reference voltage is the resistor jlB.
, 84.114a? ``It becomes a fixed V proverb.

In the above state, the evaporator outlet temperature is set to 0'
0 to 1-(', (As mentioned above, in the above state, the set voltage is Vj). 81 Hatake iE'H1'' level. This turns on the transistor s6 and the normally open contact 84 of the relay 86.
1 is closed and electromagnetic clutch 1 [is connected. Therefore, the compressor 12 operates at full capacity with a large discharge capacity.

Then, when the evaporator outlet air temperature drops below O'G, ns
a is larger than R+41A, comparator output 81
Hatake becomes ``L,'' level. Therefore, the transistor 86 is turned off, the normally open contact 88m of the relay 86 is opened, and the electromagnetic clutch 18 is disconnected.

Compressor 11! operation will be stopped. This results in evaporation 11
B's 70 strike is prevented.

Next - The room temperature is lower than the set temperature of 24°C to 26°C9. The thermistor resistance value R+1 of the temperature sensor 19 is R,,
When it increases by 1, the comparator output 87g becomes "L, '
As a result, the transistor 41 is turned off and the normally closed contact 424 of the relay 42 is closed to 1 mK, so that the solenoid valve 16 is energized. Therefore, the valve body 1 of the solenoid valve 16
6s is the coil 16 (suctioned by l, discharge pressure inlet 161) is closed and suction pressure inlet 16g
Since the valve body 116a of the on-off valve 115 is opened, the spring 11
51) to open the bow) pt. As a result, the discharge capacity of the compressor is set to a small capacity (aO% to 50% capacity) K. Further, since the transistor 41 is turned off, the base voltage is applied to the transistor 48, and the transistor 4s is turned on, so that the resistor 414 is connected in parallel with the resistor 84. As a result, the reference potential of the comparator 11 changes to a value smaller than vl, and the value of the thermistor resistance that changes the output of the comparator output 81M becomes R1 (1°C) and R14B (0'O).
From R14A'(4'O),RIaB'' (8°C)
It is set to switch to.

In the above state, if the temperature of the nitrogen evaporator 5 is higher than 4°C, the thermistor resistance value R14 of the temperature sensor 14 becomes R1.
becomes smaller than 4mm°・Comparator output FLIII-
Since it becomes H1” level, normally open contact 86 of relay 86
α is closed and the electromagnetic clutch 111 is connected. Therefore,
The compressor lz is operated with a small discharge volume and a controlled blown air temperature high. When the total air temperature at the outlet of the evaporator drops by 8°C, the thermistor resistance value Rh increases.
° becomes larger・Comparator output 81m-1)E”
Since the level reaches L, the normally open contact lag of the relay 86 is closed.The electromagnetic clutch 18 is disconnected and the operation of the compressor 12 is stopped.

As mentioned above, in one example, when the room temperature is high and a large cooling capacity is required, the compressor is used! The frost prevention control of the evaporator 415 is performed at a lower set temperature by alternating between high-capacity operation and operation stop, and the cooling capacity is improved.On the other hand, when the overflow is low and the cooling capacity is not required as much, the compression Machine 12
Small capacity operation and evaporator Suita g! By switching the temperature to a higher set temperature, it is possible to reliably prevent evaporation g15 from frosting.

Looks great on the crew! 2 It can give a ghost feeling.

FIG. 10 shows another specific example of the control circuit 46, and the main difference from the control circuit shown in FIG. be. The comparator 45 has an output of 45 m (based on the resistor 88, the thermistor resistance value R11 of the room temperature sensor 19, a potential v1 determined by the trap, and a reference potential V determined by the resistance values of the newly installed resistors 4g and 47 and 47a). is determined. The reference potential V of the comparator L/-p41s is the comparator 118'l (D reference potential, v4 y l Jli
((Vs > V4) G'il city ibb's 1.
Output BT of both comparators 87.45.

45g is the thermistor resistance value R1 of the room temperature sensor 19.
11. That is, the comparator output 456 of the comparator 45 indicates that the room temperature is, for example, the 11th
As shown in the figure, if the set temperature is higher than 22℃ of 20'C~22*c, it is the "Hl" level, and the 9m set temperature is 2G'C~
If it is lower than 20″C of 22°C, it will be “work □”. When the comparator output 451B is 1H1 level, the transistor 85 is turned on, the relay 86 is activated, the normally open contact 864f is closed, and the electromagnetic clutch 1B is activated to operate the compressor 12.

When the reverse pressure comparator output 45& is at the mL" level, the transistor 85f is turned off and the relay 86 is stopped.

As a result, the electromagnetic clutch 13 is disengaged and the compressor 12 is stopped. Another difference is the transmission process of the comparator 81 to the comparator output 811 from the circuit shown in FIG. That is, the comparator output 81g is input to the base of the transistor 46. This transistor 46 receives the comparator output 81adl "H1" and the 91st-order transistor 47 is not applied with a high voltage, and the four transistors are turned off. When the four transistors are off, the comparator output 45/& of the base comparator 45 is directly input to the transistor s5. When the comparator output sia of the comparator 31 is at the "L" or "W" level, the transistor 4B is turned off.The base voltage is applied to the reduction transistor 47, and the four transistors are turned on. Even if the output 45"2>E is at the "Hl" level, the signal at the "Hl" level is grounded because the transistor 47 is on, and no base voltage is applied to the transistor 85, so the transistor 85 is turned off. Become. This is f
i +J relay 6 breaks and normally open contact 86tL opens.

The clutch 18 is disengaged and the compressor 12 is stopped.

In the case of this embodiment, compared to the function of the four control circuits lδ in Fig. 4, the set temperature of the room temperature is set in two categories, and if the temperature is lower than 20°C as shown in Fig. 11 (→), the room temperature Sensor 19
When the value of the thermistor resistance R, - becomes larger than RteD, the comparator output 46 of the comparator 45 becomes “
When the level reaches "L" level, the transistor 85 is turned off, the relay 86 is stopped, the normally open contact 86a is opened, and the electromagnetic clutch 18 is disengaged.

The difference is that the compressor 12 has a function of stopping.

The set temperature of the Suita gust temperature of the evaporator 5 changes as shown in FIG. 11(b) according to the comparator output ays of the comparator 87, just as in the case of the control circuit shown in FIG. Therefore, in the control circuit of this embodiment, the room temperature is sensed, and if the temperature is higher than the first set temperature (24 (] to 26 C), high-capacity operation is performed, and the blowing temperature of the evaporator is lowered (0 C-1). 'C) 1st set temperature (24'O~2
g'0) Yosi low.

If the temperature is higher than the second set temperature (2 (Ifl~22-fl)), small capacity operation is performed and the outlet temperature of the evaporator 6 is set to a high ((8-(3~40)). Temperature (2
If it is lower than o-fl~22-('3), compressor 1
1! stop operating. Furthermore, the blowing temperature of the evaporator 5 is sensed, and the room temperature is set to the first set temperature (241E-1ll").
'j) If the temperature is too high, the compressor 12 is continued to operate until the air discharged from the evaporator 5 becomes lower than the low set temperature (0-1'C) to improve the cooling capacity.

- If the temperature is lower than the first set temperature (24"C to 2g'C), the cooling heat load is small, so the set temperature of the blowout temperature is set high (8°C to 4"fl) L, and the evaporator 5 Reliably prevents frosting. Therefore, the occupants can always receive comfortable cold air, frost is prevented, and the compressor is operated at an appropriate capacity.

In the above-mentioned embodiment, the sudden air temperature t immediately after the evaporator is sensed and controlled; however, the refrigerant pressure in the evaporator, t or the refrigerant temperature, t or the evaporator fin or refrigerant It is also possible to sense the surface temperature of the piping and use this as a rounding control signal for capacity control.

In addition, if the resistor 88 or the like is made into a cute resistor that can be manually adjusted externally so that the user can freely adjust the set temperature of the room, it can be used for the purpose of controlling the room temperature in addition to preventing frosting of the evaporator. Invention - Applicable.

Further, a temperature sensor 19 for room temperature is installed in the air suction part of the ventilation casing 11 (left end in FIG. 3).

The present invention can be implemented in the same manner even if the intake air temperature is sensed at a temperature close to room temperature.

Furthermore, the compressor 12 is not limited to the vane type, and other types such as a swash plate type can also be used.

[Brief explanation of drawings]

Fig. 1 is a refrigeration cycle diagram of a conventionally known automobile air conditioner, Fig. 2 is an electric circuit diagram showing the capacity control circuit of the device shown in Fig. 1, and Fig. 8 is a configuration diagram showing the overall control system of the device of the present invention. , FIG. 4 is an electric circuit diagram of an embodiment of the control circuit 15 of the device of the present invention, FIG. 7 is a sectional view showing an embodiment of the compressor used in the present invention, FIG. 7 is a sectional view showing the configuration of a compressor internal capacity variable member, and FIGS. An explanatory diagram showing the variable capacity mechanism - Fig. 9 is a sectional view of a solenoid valve used in one embodiment of the present invention, Fig. 10 is an electric circuit diagram of another embodiment of the control circuit of the present invention, and Fig. 11 ( a)
, ('bl is the comparator 81.8 shown in Fig. 10)
46 is an operational characteristic diagram of In the figure, reference numeral 6 indicates an evaporator, 1g a compressor, 18 an electromagnetic clutch, 14 and 19 a temperature sensor, 15 a control circuit, 16 an electromagnetic valve, and 18 a variable capacity member. --- Patent Applicant Nippondenso Co., Ltd. Representative Patent Attorney Hiroshi Okawa Hill O″C Between procedural amendments (method) % formula % 1. Display of the case Patent Application No. 163846 of 1982 2. Name of the invention Method for controlling a refrigeration cycle 3. Relationship with the case to be amended Patent applicant Aichi 1-1 Showa-cho, Kariya-shi, Prefecture (426) Nippondenso Co., Ltd. Representative: Fumi Hirano 4, Agent: Kodama Building, 3-3-4 Meieki, Nakamura-ku, Nagoya, Aichi Prefecture 450 (Tel: <052> 583-9720) ＞February 4, 1981, column 7 of the title of the invention in the specification to be amended, content of the amendment (1) "Refrigerating cycle control method" in the second line of the first page of the specification was changed to [refrigerating cycle Control method J and corrections.

Claims (1)

[Scope of Claims] (1) A method for controlling a refrigeration cycle having a variable capacity compressor configured to be able to change the discharge amount in stages, the room temperature to be air-conditioned or the *C temperature during suction. The discharge amount of the compressor is switched by sensing, and the temperature or refrigerant pressure related to the degree of cooling of the evaporator is sensed to control intermittent operation, and the temperature or refrigerant pressure related to the degree of cooling of the evaporator is controlled by changing the discharge capacity. A method for controlling a refrigeration cycle, characterized by controlling a set temperature or a set pressure of the refrigeration cycle. +2) When the room temperature or the suction air temperature is higher than the set temperature, set the discharge capacity of the pressure machine to a large capacity, and set the temperature or set pressure of the temperature or refrigerant pressure related to the degree of cooling of the evaporator. When the room temperature or suction air temperature is lower than the set temperature, the discharge capacity of the d1 nuclear compressor is set to a small volume. The method of controlling carpet according to claim 1, wherein the set temperature or set pressure of the carpet is changed to a higher value. (3) If the room temperature or suction air temperature is higher than the first set degree of mud, the discharge capacity of the compressor is set to a large capacity, and the temperature is within the cooling degree of the evaporator 4 or the set temperature of the refrigerant 1 mocha. When the set pressure is lowered and the room temperature or suction air temperature is lower than the first set temperature and daytime than the second set temperature,
The discharge capacity of the compressor is set to a small capacity, and the set temperature or set pressure of the temperature or refrigerant pressure related to the degree of cooling of the evaporator is set to the lowest, and the room temperature or the suction air width is set to the second setting.
The control method according to claim 1, wherein the aphrodisiac is stopped when the crystallinity is unsatisfactory.