JP2002286316A - Freezing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform an operation capable of meeting various requests of users. SOLUTION: When the evaporating capacity of a second indoor heat exchange (91) is insufficient upon maximum capacity of a compressing mechanism (40) in a cooling cycle, the air volume of a volume of a first indoor fan (83) of a first indoor heat exchanger (81) is lowered. When the evaporating capacity of the second indoor heat exchanger (91) is still insufficient even after the air volume is lowered, the evaporation of the first indoor heat exchanger (81) is stopped. When the evaporating capacity of the second indoor heat exchanger (91) is insufficient upon maximum capacity of the compressing mechanism (40) in a heating cycle, the air volume of the first indoor fan (83) of the first indoor heat exchanger (81) is increased. When the evaporating capacity of the second indoor heat exchanger (91) is still insufficient even after the air volume is increased, the air volume of a ventilator (87) is increased. In such a way, the capacity of the second indoor heat exchanger (91) is primarily controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a refrigeration apparatus,
In particular, it relates to a priority control measure for an air-conditioning heat exchanger or a cooling-only heat exchanger.

[0002]

2. Description of the Related Art Hitherto, a refrigerating apparatus for performing a refrigerating cycle has been known, and is widely used as an air conditioner for cooling and heating a room or a refrigerator for storing foods and the like.
Some refrigeration systems are configured to perform both air conditioning and refrigeration, as disclosed in WO 98/542600. This type of refrigerating apparatus includes, for example, an air-conditioning heat exchanger, a cooling-specific heat exchanger, and a refrigerating heat exchanger, and is suitable for being installed in a convenience store or the like. This is because the air conditioning in the store and the cooling of the showcase can be performed only by installing one refrigeration apparatus.

[0003]

In this type of refrigeration system, refrigeration must always be given the utmost importance, and sometimes air conditioning at a sales floor or the like is more important. For example, even if the inside temperature of the showcase slightly exceeds the set temperature, the quality of the product may not be significantly affected depending on the type of product. In such a case, some users may want to emphasize comfort in the store.

However, in the conventional refrigeration system, the control of the air-conditioning heat exchanger, the cooling-only heat exchanger, and the refrigeration heat exchanger is
Each was done individually and did not control these heat exchangers in conjunction. As a result, the comfort in the store or the like may be impaired against the demands of the user.

Further, in the conventional refrigeration system, it is necessary to provide an outdoor unit having a capacity which is the sum of the maximum capacity of each of the air conditioning heat exchanger, the cooling heat exchanger, and the refrigeration heat exchanger. As a result, there is a problem that the capacity of the outdoor unit becomes larger than necessary.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to provide a refrigeration apparatus which can be operated to meet various demands of users.

[0007]

<Summary of the Invention> In the present invention, an air conditioning heat exchanger or a cooling only heat exchanger is preferentially controlled.

<Solution> Specifically, as shown in FIG. 1, the first invention comprises a compression mechanism (40), a heat source side heat exchanger (32), and an air conditioning heat exchanger for cooling and heating the room. (81)
And heat exchanger for cooling only for indoor cooling (91)
And a cooling heat exchanger (101) for cooling the inside of the refrigerator. The refrigerant is condensed by the heat source side heat exchanger (32) to form an air conditioning heat exchanger (81) and a cooling only heat exchanger (91). A cooling cycle in which the refrigerant is evaporated in the cooling heat exchanger (101), and a heat exchanger exclusively used for cooling by condensing the refrigerant in the air conditioning heat exchanger (81) (91)
And a refrigerant circuit (1A) for switching between a heating cycle for evaporating the refrigerant in the cooling heat exchanger (101). And, when the compression mechanism (40) has the maximum capacity, there is provided a capacity control means (210, 220) for preferentially controlling the evaporation capacity of the air conditioning heat exchanger (81) or the cooling only heat exchanger (91). .

According to a second aspect of the present invention, in the first aspect, the capacity control means (210) includes a cooling-only heat exchanger (9) when the compression mechanism (40) has the maximum capacity in the cooling cycle.
If the evaporating capacity of (1) is insufficient, the air-conditioning air flow reduction unit (21) reduces the air volume of the air-conditioning fan (83) of the air-conditioning heat exchanger (81)
1).

[0010] In a third aspect based on the second aspect, the capacity control means (210) includes an air-conditioning air volume reduction section (211).
Is equipped with an air-conditioning stop unit (212) for stopping the evaporation of the air-conditioning heat exchanger (81) if the evaporation capacity of the cooling-specific heat exchanger (91) is insufficient even after the air volume of the air-conditioning fan (83) is reduced Configuration.

[0011] In a fourth aspect based on the third aspect, the capacity control means (210) comprises: a cooling-only heat exchanger (9) when the capacity of the compression mechanism (40) in the heating cycle is at its maximum capacity.
If the evaporation capacity of (1) is insufficient, the air-conditioning air volume increasing unit (21) increases the air volume of the air-conditioning fan (83) of the air-conditioning heat exchanger (81).
3).

According to a fifth aspect, in the fourth aspect, a ventilation means (87) for ventilating a room in which the air conditioning heat exchanger (81) is installed is provided, while a capacity control means (210).
If the evaporation capacity of the cooling-specific heat exchanger (91) is insufficient even after the air-conditioning air volume increasing unit (213) increases the air volume of the air-conditioning fan (83), ventilation that increases the air volume of the ventilation means (87) The control unit (214) is provided.

[0013] In a sixth aspect based on the first aspect, the capacity control means (220) is configured to reduce the evaporation capacity of the air conditioning heat exchanger (81) when the compression mechanism (40) has the maximum capacity in the cooling cycle. If there is a shortage, the cooling air flow reduction unit (22) that reduces the air flow of the cooling fan (93) of the cooling heat exchanger (91)
1).

[0014] In a seventh aspect based on the sixth aspect, the capacity control means (220) includes a cooling air volume reduction section (221).
If the evaporation capacity of the air conditioning heat exchanger (81) is insufficient even after the air flow of the cooling fan (93) is reduced, the cooling fan (93) is provided with a cooling stop (222) for stopping the evaporation of the cooling heat exchanger (91). Configuration.

That is, in the present invention, one of the priority control of the cooling only heat exchanger (91) and the priority control of the air conditioning heat exchanger (81) is performed.

The priority control of the cooling only heat exchanger (91) is performed when the compression mechanism (40) has the maximum capacity during the cooling cycle and when the evaporation capacity of the cooling only heat exchanger (91) is insufficient. First, the air-conditioning air flow reduction unit (211) reduces the air flow of the air-conditioning fan (83) of the air-conditioning heat exchanger (81) to reduce the evaporator capacity of the air-conditioning heat exchanger (81), and the heat exchange for cooling only. Increase the evaporation capacity of the vessel (91).

Thereafter, even after the air-conditioning air flow reducing section (211) lowers the air flow of the air-conditioning fan (83), if the evaporating capacity of the cooling-specific heat exchanger (91) is insufficient, the air-conditioning stopping section ( 212) stops the evaporation of the air conditioning heat exchanger (81) and increases the evaporation capacity of the cooling only heat exchanger (91).

In the heating cycle, when the compression mechanism (40) has the maximum capacity, the cooling-specific heat exchanger (91)
If the evaporation capacity of the air conditioning heat exchanger (81) is insufficient, first, the air conditioning air volume increasing unit (213) increases the air volume of the air conditioning fan (83) of the air conditioning heat exchanger (81) to reduce the condensation capacity of the air conditioning heat exchanger (81). And the evaporation capacity of the cooling-specific heat exchanger (91) is increased.

Thereafter, even after the air-conditioning air volume increasing unit (213) increases the air volume of the air-conditioning fan (83), if the evaporation capacity of the cooling-specific heat exchanger (91) is insufficient, the ventilation control unit (213). 214) increases the air volume of the ventilation means (87), takes in outside air, increases the condensation capacity of the air conditioning heat exchanger (81), and increases the evaporation capacity of the cooling only heat exchanger (91).

On the other hand, in the priority control of the air conditioning heat exchanger (81), if the evaporation capacity of the air conditioning heat exchanger (81) is insufficient during the cooling cycle, first, the cooling air flow reducing section (22)
1) reduces the air volume of the cooling fan (93) to reduce the evaporator capacity of the cooling-specific heat exchanger (91) and increases the evaporating capacity of the air-conditioning heat exchanger (81).

Thereafter, even after the cooling air flow reducing section (221) reduces the air flow of the cooling fan (93), if the evaporation capacity of the air conditioning heat exchanger (81) is insufficient, the cooling stop section (222) ) Stops the evaporation of the cooling only heat exchanger (91) and increases the evaporation capacity of the air conditioning heat exchanger (81).

[0022]

Therefore, according to the present invention, priority control of the cooling-specific heat exchanger (91) or priority control of the air-conditioning heat exchanger (81) can be performed, so that the demand of the user can be surely met. Control can be performed, and comfort can be improved.

Since the air-conditioning heat exchanger (81) and the cooling-only heat exchanger (91) are controlled in association with each other, the compression mechanism (40)
Can be set small. As a result, the entire apparatus can be made inexpensive.

[0024]

Embodiments of the present invention will be described below in detail with reference to the drawings.

As shown in FIGS. 1 and 2, a refrigeration apparatus (10) according to the present embodiment is provided in a convenience store for cooling a showcase and cooling and heating the inside of the store.

The refrigeration system (10) comprises a high-temperature side refrigerant circuit (20), a low-temperature side refrigerant circuit (25), a controller (200)
And a changeover switch (250), and a refrigerant circuit (1A) for performing a so-called binary refrigeration cycle. Also,
The refrigeration apparatus (10) includes an outdoor unit (11), a first indoor unit (12), a second indoor unit (13), a refrigeration unit (14), a cascade unit (15), and a refrigeration unit (16). I have. And the said refrigerant circuit (1A)
It is configured to switch between a cooling cycle and a heating cycle.

The first indoor unit (12) is configured to switch between cooling and heating. The first indoor unit (12) is installed in, for example, a sales floor.
The second indoor unit (13) is configured only for cooling. The second indoor unit (13) is installed in a room with a heat load throughout the year, such as a kitchen, for example, and performs only cooling. The refrigeration unit (14) is installed in a refrigerated showcase and cools the air inside the showcase. The refrigeration unit (16) is installed in a refrigeration showcase and cools the air inside the showcase.

<Structure of High Temperature Side Refrigerant Circuit> The high temperature side refrigerant circuit (20) includes an outdoor circuit (30), first and second indoor circuits (80, 90), a refrigeration circuit (100), Side cascade circuit (110) and first and second liquid side communication pipes (21, 23)
And the first and second gas side communication pipes (22, 24). Of these, the first indoor circuit (80) is connected via a first liquid side communication pipe (21) and a first gas side communication pipe (22).
Connected to the outdoor circuit (30). On the other hand, the second indoor circuit (90), the refrigeration circuit (100), and the high-temperature cascade circuit (110) are connected via the second liquid-side communication pipe (23) and the second gas-side communication pipe (24). , And connected in parallel to the outdoor circuit (30). The high-temperature side refrigerant circuit (20) is filled with a high-temperature side refrigerant.

The outdoor circuit (30) includes an outdoor unit (1).
It is stored in 1). The outdoor circuit (30) has a compression mechanism (4
0), a four-way switching valve (31), an outdoor heat exchanger (32),
An outdoor expansion valve (34), a receiver (33), a first and a second
A liquid-side stop valve (35, 37) and first and second gas-side stop valves (36, 38) are provided. The outdoor circuit (30) is provided with a gas vent pipe (64), a pressure equalizing pipe (66), and a liquid supply pipe (68).

The compression mechanism (40) includes a first compressor (41)
And the second compressor (42) are connected in parallel, and constitute compressor means. First and second compressors (41, 42)
Are closed-type, high-pressure dome-type scroll compressors. That is, these compressors (41, 42) are configured such that the compression means and the electric motor for driving the compression means are housed in a cylindrical housing. The illustration of the compression means and the electric motor is omitted. The first compressor (41) has a variable capacity in which the number of revolutions of the electric motor is changed stepwise or continuously. The second compressor (42) is of a constant capacity in which the electric motor is always driven at a constant rotation speed. That is, the overall capacity of the compression mechanism (40) is variable by changing the capacity of the first compressor (41) and starting and stopping the second compressor (42).

The compression mechanism (40) includes a suction pipe (43) and a discharge pipe (44). The inlet end of the suction pipe (43) is connected to the first port of the four-way switching valve (31), and the outlet end is branched into two and connected to the suction sides of the compressors (41, 42). Have been. The discharge pipe (44) has an inlet end branched into two and connected to the discharge side of each compressor (41, 42),
The outlet end is connected to the second port of the four-way switching valve (31). Further, a discharge-side check valve (45) is provided in a branch pipe of the discharge pipe (44) connected to the second compressor (42). The discharge-side check valve (45) allows only the flow of the refrigerant in the direction flowing out of the second compressor (42).

The compression mechanism (40) includes an oil separator (51), an oil return pipe (52), and an oil equalizing pipe (54). The oil separator (51) is provided in the middle of the discharge pipe (44). The oil separator (51) is for separating refrigeration oil from refrigerant discharged from the compressors (41, 42). One end of the oil return pipe (52) is connected to the oil separator (51),
The other end is connected to the suction pipe (43). The oil return pipe (52) is provided with the refrigerating machine oil separated by the oil separator (51),
For returning to the suction side of the compressor (41, 42),
An oil return solenoid valve (53) is provided. One end of the oil equalizing pipe (54) is connected to the second compressor (42), and the other end is connected to the suction pipe (43) near the suction side of the first compressor (41). This oil equalizing pipe (54) is connected to each compressor (41, 42)
For equalizing the amount of refrigerating machine oil stored in the housing, and is provided with an oil equalizing solenoid valve (55).

The four-way switching valve (31) has a third port connected to the first gas side shut-off valve (36) by a pipe, and a fourth port.
Port is connected to the upper end of the outdoor heat exchanger (32) by piping. The four-way switching valve (31) has a state in which the first port and the third port are in communication and the second port and the fourth port are in communication (a state indicated by a solid line in FIG. 1); And the fourth port communicates with each other, and the second and third ports communicate with each other (the state shown by the broken line in FIG. 1).

The outdoor heat exchanger (32) is a heat source side heat exchanger, and is constituted by a cross-fin type fin-and-tube heat exchanger. In the outdoor heat exchanger (32), the high-temperature side refrigerant circulating in the high-temperature side refrigerant circuit (20) exchanges heat with the outdoor air.

The receiver (33) is a cylindrical container for storing a refrigerant. The receiver (33) is connected to the outdoor heat exchanger (32) and the first liquid side closing valve (35) via the inflow pipe (60) and the outflow pipe (62).

The inlet end of the inflow pipe (60) is branched into two branch pipes (60a, 60b), and the outlet end is connected to the upper end of the receiver (33). The first branch pipe (60a) of the inflow pipe (60) is connected to the lower end of the outdoor heat exchanger (32). The first branch pipe (60a) is provided with a first inflow check valve (61a). First inflow check valve (61
a) allows only the flow of refrigerant from the outdoor heat exchanger (32) to the receiver (33). The second branch pipe (60b) of the inflow pipe (60) is connected to the first liquid side closing valve (35). This second branch pipe (60b) has a second inflow check valve (61
b) is provided. The second inflow check valve (61b)
Only the flow of the refrigerant from the liquid side closing valve (35) to the receiver (33) is allowed.

The outflow pipe (62) has its inlet end connected to the lower end of the receiver (33), and its outlet end branched into two branch pipes (62a, 62b). The first branch pipe (62a) of the outflow pipe (62) is connected to the lower end of the outdoor heat exchanger (32). The first branch pipe (62a) is provided with the outdoor expansion valve (34). The second branch pipe (62b) of the outflow pipe (62) is connected to the first liquid side closing valve (35). The second branch pipe (62b) is provided with an outflow check valve (63). Outflow check valve (63), receiver (33)
Only the flow of the refrigerant from to the first liquid side closing valve (35) is allowed.

The second liquid-side stop valve (37) is connected to the outflow pipe (6).
The pipe is connected between the outflow check valve (63) and the receiver (33) in the second branch pipe (62b) of 2). On the other hand, the second gas-side stop valve (38) is connected to a suction pipe (43) of the compression mechanism (40) by piping.

The degassing pipe (64) has one end connected to the upper end of the receiver (33) and the other end connected to the suction pipe (4).
3) Connected to. The gas vent pipe (64) is provided with a gas vent solenoid valve (65). When the gas release solenoid valve (65) is opened and closed, the flow of the refrigerant in the gas release pipe (64) is interrupted.

One end of the pressure equalizing pipe (66) is connected to the gas venting solenoid valve (65) in the gas venting pipe (64) and the receiver (3).
The other end is connected to the discharge pipe (44). Further, the equalizing pipe (66) has a check valve (67) for equalizing that allows only the flow of the refrigerant from one end to the other end.
Is provided.

The first indoor circuit (80) is housed in the first indoor unit (12). This first indoor circuit (80)
Is a pipe connection of a first indoor heat exchanger (81), which is an air conditioning heat exchanger, and a first indoor expansion valve (82) in series. The first indoor expansion valve (82) is a first indoor heat exchanger (81).
Is connected to the lower end. The first of the first indoor circuit (80)
The end on the indoor expansion valve (82) side is connected to the first liquid side closing valve (35) of the outdoor circuit (30) via the first liquid side connecting pipe (21). On the other hand, the end of the first indoor circuit (80) on the first indoor heat exchanger (81) side is connected to the first gas side shut-off valve of the outdoor circuit (30) via the first gas side communication pipe (22). Connected to (36).

The first indoor heat exchanger (81)
It becomes an evaporator during the cooling cycle of the refrigerant circuit (1A) and a condenser during the heating cycle.

The second indoor circuit (90) is housed in the second indoor unit (13). This second indoor circuit (90)
Is the second indoor heat exchanger (91) which is a cooling heat exchanger
And a second indoor expansion valve (92) connected in series by piping. The second indoor expansion valve (92) is connected to a lower end of the second indoor heat exchanger (91).

The refrigeration circuit (100) includes a refrigeration unit (1
4) is stored. The refrigeration circuit (100) includes a refrigeration heat exchanger (101), which is a refrigeration heat exchanger, and a refrigeration expansion valve (1).
02) are connected in series by piping. The refrigerating expansion valve (102) is connected to the upper end of the refrigerating heat exchanger (101).

The high temperature side cascade circuit (110) is housed in a cascade unit (15). This high-temperature side cascade circuit (110) is a cascade heat exchanger (111)
And a cascade expansion valve (112) connected in series by piping. The cascade expansion valve (112) is connected to an upper end on the primary side of the cascade heat exchanger (111).

As described above, for the outdoor circuit (30), the second liquid side communication pipe (23) and the second gas side communication pipe (24)
, The second indoor circuit (90), the refrigeration circuit (100), and the high-temperature side cascade circuit (110) are connected in parallel with each other.

More specifically, one end of the second liquid side communication pipe (23) is connected to the second liquid side closing valve (37). Also,
The second liquid side communication pipe (23) is branched into three at the other end,
The end of the second indoor circuit (90) on the side of the second indoor expansion valve (92) and the refrigeration expansion valve (102) in the refrigeration circuit (100)
And an end on the cascade expansion valve (112) side of the high temperature side cascade circuit (110).

On the other hand, one end of the second gas side communication pipe (24) is connected to the second gas side closing valve (38). Also,
The second gas-side communication pipe (24) is branched into three at the other end, and is connected to the second indoor heat exchanger (9) in the second indoor circuit (90).
1) The end of the side, the end of the refrigeration heat exchanger (101) in the refrigeration circuit (100), and the end of the high-temperature cascade circuit (110) on the cascade heat exchanger (111) side Have been.

The first and second indoor heat exchangers (81, 91) and the refrigerating heat exchanger (101) are constituted by cross-fin type fin-and-tube heat exchangers. First
In the second indoor heat exchanger (81, 91), the high-temperature side refrigerant circuit (2
Heat exchange between the high-temperature side refrigerant circulating through 0) and the indoor air is performed. In the refrigeration heat exchanger (101), the high-temperature side refrigerant circuit (2
The high-temperature side refrigerant circulating through 0) and the air in the refrigerator exchange heat.

<Structure of Low Temperature Refrigerant Circuit> The low temperature refrigerant circuit (25) includes a low temperature cascade circuit (120), a refrigeration circuit (130), a third liquid side communication pipe (26), It is constituted by a gas side communication pipe (27). The low temperature side cascade circuit (120) and the refrigeration circuit (130) are connected via a third liquid side communication pipe (26) and a third gas side communication pipe (27). The low-temperature side refrigerant circuit (25) is filled with a low-temperature side refrigerant.

The low temperature side cascade circuit (120) is housed in the cascade unit (15). The low-temperature cascade circuit (120) includes a low-temperature compressor (121), a receiver (123), a third liquid-side shutoff valve (124), and a third gas-side shutoff valve (125). 1 and 2, "A" in FIG. 2 corresponds to "A" in FIG. 1, and "B" in FIG. 2 corresponds to "B" in FIG.

The discharge side of the low-temperature side compressor (121) is connected to a cascade heat exchanger (11) through a discharge side check valve (122).
This discharge-side check valve (122), which is connected to the upper end of the secondary side in (1), allows only the flow of refrigerant from the low-temperature side compressor (121) to the cascade heat exchanger (111). .
On the other hand, the suction side of the low temperature side compressor (121) is connected to the third gas side closing valve (125) by piping. The lower end of the secondary side of the cascade heat exchanger (111) is connected to the upper part of the receiver (123) by piping. The bottom of the receiver (123) is connected to the third liquid-side stop valve (124) by piping.

The refrigeration circuit (130) includes a refrigeration unit (1
6) is stored. The refrigeration circuit (130) includes a refrigeration heat exchanger (131), which is a cooling heat exchanger, and a refrigeration expansion valve (1).
32) are connected in series by piping. The refrigeration expansion valve (132) is connected to the upper end of the refrigeration heat exchanger (131). The end of the refrigeration circuit (130) on the side of the refrigeration expansion valve (132) is connected to the third liquid side shut-off valve (124) of the low temperature side cascade circuit (120) via the third liquid side communication pipe (26). It is connected. On the other hand, the end of the refrigerating circuit (130) on the side of the refrigerating heat exchanger (131) is connected via a third gas-side connecting pipe (27) to the third gas-side shut-off valve ( 125)

The cascade heat exchanger (111) is constituted by a plate heat exchanger. The cascade heat exchanger (111) has a primary flow path and a secondary flow path defined therein. As described above, the cascade heat exchanger (111) has a primary side connected to the high-temperature side refrigerant circuit (20) and a secondary side connected to the low-temperature side refrigerant circuit (25). The cascade heat exchanger (111) is for exchanging heat between the high-temperature side refrigerant flowing through its primary side and the low-temperature side refrigerant flowing through its secondary side. That is, the cascade heat exchanger (111) functions as a cascade condenser in the binary refrigeration cycle.

<Other Configuration> The outdoor unit (11)
Is provided with an outdoor fan (70) and an outside air temperature sensor (71). The outdoor fan (70) is an outdoor heat exchanger (32)
It is for sending outdoor air to Outside temperature sensor (7
1) is for detecting the temperature of the outdoor air sent to the outdoor heat exchanger (32).

The outdoor circuit (30) housed in the outdoor unit (11) is provided with various sensors. Specifically, the outdoor heat exchanger (32) is provided with an outdoor heat exchanger temperature sensor (72) for detecting the heat transfer tube temperature. The suction pipe (43) has a suction pipe temperature sensor (73) for detecting the suction refrigerant temperature of the compressor (41, 42) and a low pressure for detecting the suction refrigerant pressure of the compressor (41, 42). A pressure sensor (74) is provided. In the discharge pipe (44),
A discharge pipe temperature sensor (75) for detecting the discharge refrigerant temperature of the compressor (41, 42), a high pressure sensor (76) for detecting the discharge refrigerant pressure of the compressor (41, 42), A pressure switch (77) is provided. Degassing pipe (64)
Is provided with a vent tube temperature sensor (78) for detecting the temperature of the refrigerant after passing through the vent gas solenoid valve (65).

The first indoor unit (12) is provided with a first indoor fan (83) and a first internal temperature sensor (84). The first indoor fan (83) is an air-conditioning fan for sending indoor air to the first indoor heat exchanger (81). The first inside air temperature sensor (84) is for detecting the temperature of room air sent to the first indoor heat exchanger (81).

The first indoor circuit (80) housed in the first indoor unit (12) is provided with a temperature sensor. Specifically, the first indoor heat exchanger (81) is provided with a first indoor heat exchanger temperature sensor (85) for detecting the heat transfer tube temperature. Near the upper end of the first indoor heat exchanger (81) in the first indoor circuit (80), a first gas side temperature sensor (86) for detecting the temperature of the gas refrigerant flowing through the first indoor circuit (80) is provided. Is provided.

The first indoor unit (12) includes:
A ventilation fan (87) as ventilation means for ventilating the room is provided.

The second indoor unit (13) is provided with a second indoor fan (93) and a second internal temperature sensor (94). The second indoor fan (93) is a cooling fan for sending indoor air to the second indoor heat exchanger (91). The second inside air temperature sensor (94) is for detecting the temperature of room air sent to the second indoor heat exchanger (91).

The second indoor circuit (90) housed in the second indoor unit (13) is provided with a temperature sensor. Specifically, the second indoor heat exchanger (91) is provided with a second indoor heat exchanger temperature sensor (95) for detecting the heat transfer tube temperature. Near the upper end of the second indoor heat exchanger (91) in the second indoor circuit (90), a second gas side temperature sensor (96) for detecting the temperature of the gas refrigerant flowing through the second indoor circuit (90). Is provided.

The refrigerating unit (14) is provided with a refrigerating fan (103) and a refrigerating temperature sensor (104). The refrigeration fan (103) is for sending air in the refrigerator to the refrigeration heat exchanger (101). The refrigeration temperature sensor (104) is for detecting the temperature of the inside air sent to the refrigeration heat exchanger (101).

The refrigeration circuit (100) housed in the refrigeration unit (14) is provided with a temperature sensor. Specifically, the refrigerating heat exchanger (101) is provided with a refrigerating heat exchanger temperature sensor (105) for detecting the heat transfer tube temperature. A refrigeration gas side temperature sensor (106) for detecting the temperature of the gas refrigerant flowing through the refrigeration circuit (100) is provided near the lower end of the refrigeration heat exchanger (101) in the refrigeration circuit (100).

The high-temperature-side cascade circuit (110) housed in the cascade unit (15) is provided with a cascade-outflow-side temperature sensor (113). The cascade outlet temperature sensor (113) is connected to the cascade heat exchanger (1).
This is for detecting the temperature of the high-temperature side refrigerant flowing out from the primary side in 11).

The refrigeration unit (16) is provided with a refrigeration fan (133) and a refrigeration temperature sensor (134). The freezing fan (133) is for sending air in the freezer to the freezing heat exchanger (131). The refrigeration temperature sensor (134) is for detecting the temperature of the air in the refrigerator sent to the refrigeration heat exchanger (131).

The refrigeration circuit (130) housed in the refrigeration unit (16) is provided with a temperature sensor. Specifically, the refrigeration heat exchanger (131) is provided with a refrigeration heat exchanger temperature sensor (135) for detecting the heat transfer tube temperature. A refrigeration gas side temperature sensor (136) for detecting the temperature of the gas refrigerant flowing through the refrigeration circuit (130) is provided near the lower end of the refrigeration heat exchanger (131) in the refrigeration circuit (130).

The controller (200) controls the operation of the refrigeration system (10) in response to detection signals from the various sensors and the like, and constitutes control means. For example, the controller (200) controls the opening degree of the outdoor expansion valve (34), the switching operation of the four-way switching valve (31), and the compression mechanism (40).
And the air volume of the outdoor fan (70). Further, the controller (200) is configured to execute the priority control, and executes the selected control operation. This controller (200) is an outdoor unit (11)
It is stored in.

That is, the controller (200) includes:
At the time of the maximum capacity of the compression mechanism (40), the air-conditioning capacity control means (210) for giving priority to the evaporation capacity of the second heat exchanger and the control for giving priority to the evaporation capacity of the first indoor heat exchanger (81). Cooling capacity control means (220).

The air conditioning capacity control means (210) controls the capacity of the first indoor heat exchanger (81) in order to give priority to the second indoor heat exchanger (91), which is a heat exchanger exclusively for cooling. Give priority to the cooling operation of the two indoor units (13). The air-conditioning capacity control means (210) includes an air-conditioning air flow reducing section (211), an air-conditioning stopping section (212), an air-conditioning air flow increasing section (213), and a ventilation control section (214).

The cooling capacity control means (220) gives priority to the first indoor heat exchanger (81) which is an air conditioning heat exchanger.
The capacity of the second indoor heat exchanger (91) is controlled, and the cooling operation of the first indoor unit (12) is prioritized. The cooling capacity control means (220) includes a cooling air volume reduction section (221) and a cooling stop section (222).

When the evaporation capacity of the second indoor heat exchanger (91) is insufficient during the maximum capacity of the compression mechanism (40) in the cooling cycle, the first indoor heat exchanger (81) ), The air volume of the first indoor fan (83) is reduced.

The air-conditioning stopping section (212) has a shortage of the evaporation capacity of the second indoor heat exchanger (91) even after the air-conditioning air flow reducing section (211) reduces the air volume of the first indoor fan (83). Then, the evaporation of the first indoor heat exchanger (81) is stopped.
That is, the air-conditioning stop unit (212) suspends the cooling operation of the first indoor unit (12), and turns off the so-called thermo-off.

The air-conditioning air volume increasing section (213) is configured to operate the first indoor heat exchanger (81) when the evaporation capacity of the second indoor heat exchanger (91) is insufficient during the maximum capacity of the compression mechanism (40) in the heating cycle. ) To increase the air volume of the first indoor fan (83).

The ventilation control section (214) has a problem that the evaporation capacity of the second indoor heat exchanger (91) is insufficient even after the air-conditioning air volume increasing section (213) increases the air volume of the first indoor fan (83). Then, the air volume of the ventilation fan (87) is increased.

When the evaporating capacity of the first indoor heat exchanger (81) is insufficient at the maximum capacity of the compression mechanism (40) in the cooling cycle, the second indoor heat exchanger (91) ), The air volume of the second indoor fan (93) is reduced.

The cooling stop section (222) is configured to stop the evaporation of the first indoor heat exchanger (81) even after the cooling air volume reduction section (221) reduces the air volume of the second indoor fans (93) (93). When the capacity is insufficient, the evaporation of the second indoor heat exchanger (91) is stopped. That is, the cooling stop section (222) suspends the cooling operation of the second indoor unit (13), and turns off the so-called thermo-off.

The operation changeover switch (250) is for inputting an external signal for selecting the priority control executed by the controller (200), and constitutes an input means. That is, by operating the operation changeover switch (250), the priority control of the second indoor unit (13) and the priority control of the first indoor unit (12) executed by the controller (200) are arbitrarily selected. The operation changeover switch (250) is housed in the outdoor unit (11).

-Operation- During the operation of the refrigeration system (10), the high-temperature side refrigerant circuit (2
The refrigerant circulates in each of phase 0) and the low-temperature side refrigerant circuit (25) while changing phase, and a vapor compression refrigeration cycle is performed.
The refrigerating device (10) performs a cooling operation (cooling cycle) for cooling the indoor air in the first indoor unit (12) and a heating operation (heating cycle) for heating the indoor air in the first indoor unit (12). To switch.

<Cooling Operation> In the cooling operation, in the high-temperature side refrigerant circuit (20), the outdoor heat exchanger (32) is used as a condenser, and the first indoor heat exchanger (81) and the second indoor heat exchanger ( 9
1), a refrigeration cycle is performed using the refrigerating heat exchanger (101) and the cascade heat exchanger (111) as evaporators. On the other hand, in the low-temperature side refrigerant circuit (25), a refrigeration cycle is performed using the cascade heat exchanger (111) as a condenser and the refrigeration heat exchanger (131) as an evaporator.

During the cooling operation, the four-way switching valve (31) is switched to the state shown by the solid line in FIG. Further, the first indoor expansion valve (82), the second indoor expansion valve (92), the refrigeration expansion valve (102), the cascade expansion valve (112), and the refrigeration expansion valve (132) have a predetermined opening degree. The outdoor expansion valve (34) is fully closed. Oil return solenoid valve (53), oil equalizing solenoid valve (55),
The degassing solenoid valve (65) and the liquid supply solenoid valve (69) are normally kept closed, but are opened and closed as needed.

First, the operation of the high-temperature side refrigerant circuit (20) will be described. When the compressors (41, 42) of the compression mechanism (40) are operated, the high-temperature side refrigerant compressed by the compressors (41, 42) is discharged to the discharge pipe (44). The high-temperature side refrigerant flows into the outdoor heat exchanger (32) through the four-way switching valve (31). In the outdoor heat exchanger (32), the high-temperature side refrigerant releases heat to outdoor air and condenses. The high-temperature side refrigerant condensed in the outdoor heat exchanger (32) flows into the first branch pipe (60a) of the inflow pipe (60), passes through the first inflow check valve (61a), and passes through the receiver (33).
Flows into The high-temperature side refrigerant of the receiver (33) flows into the outflow pipe (62). Thereafter, the high-temperature side refrigerant is divided into two flows, one of which flows through the outflow check valve (63) to the first liquid side closing valve (35), and the other flows to the second liquid side closing valve (37).

The high-temperature side refrigerant that has passed through the first liquid side closing valve (35) passes through the first liquid side communication pipe (21), and then enters the first indoor circuit (8).
0). In the first indoor circuit (80), after the inflowing high-temperature side refrigerant is decompressed by the first indoor expansion valve (82),
It flows into the indoor heat exchanger (81). The first indoor heat exchanger (8
In 1), the high temperature side refrigerant absorbs heat from room air and evaporates. That is, in the first indoor heat exchanger (81), the indoor air is cooled. The high-temperature side refrigerant evaporated in the first indoor heat exchanger (81) flows through the first gas side communication pipe (22), passes through the first gas side shutoff valve (36), and flows into the outdoor circuit (30). . Thereafter, the high-temperature side refrigerant passes through the four-way switching valve (31) and flows into the suction pipe (43).

The high-temperature side refrigerant that has passed through the second liquid side closing valve (37) flows into the second liquid side communication pipe (23). The high-temperature side refrigerant is then divided into three parts, and is divided into the second indoor circuit (9).
0), refrigeration circuit (100), or high-temperature cascade circuit (11
Flows to 0).

The high-temperature side refrigerant flowing into the second indoor circuit (90) is depressurized by the second indoor expansion valve (92), and then flows into the second indoor heat exchanger (91). In the second indoor heat exchanger (91), the high-temperature side refrigerant absorbs heat from room air and evaporates. That is, in the second indoor heat exchanger (91), the indoor air is cooled.

The high-temperature side refrigerant that has flowed into the refrigeration circuit (100) flows into the refrigeration heat exchanger (101) after being depressurized by the refrigeration expansion valve (102). In the refrigeration heat exchanger (101),
The high temperature side refrigerant absorbs heat from the air inside the refrigerator and evaporates.
That is, in the refrigerating heat exchanger (101), the air in the refrigerator is cooled.

The high-temperature refrigerant flowing into the high-temperature cascade circuit (110) is depressurized by the cascade expansion valve (112) and then flows into the cascade heat exchanger (111). In the cascade heat exchanger (111), the high-temperature side refrigerant flowing on the primary side absorbs heat from the low-temperature side refrigerant flowing on the secondary side and evaporates.

The second indoor heat exchanger (91), the refrigeration circuit (10
0) or the high-temperature side refrigerant evaporated in the cascade heat exchanger (111) flows into the second gas side communication pipe (24) and merges, and then passes through the second gas side shutoff valve (38). And flows into the suction pipe (43). In the suction pipe (43), the high temperature side refrigerant sent through the first gas side communication pipe (22)
The high-temperature side refrigerant sent through the second gas side communication pipe (24) merges. The high-temperature side refrigerant flowing through the suction pipe (43)
It is sucked into the compressors (41, 42) of the compression mechanism (40). These compressors (41, 42) compress the drawn high-temperature side refrigerant and discharge it again. In the high-temperature side refrigerant circuit (20), such circulation of the high-temperature side refrigerant is repeated.

Next, the operation of the low temperature side refrigerant circuit (25) will be described. When the low temperature side compressor (121) is operated, the compressed low temperature side refrigerant is discharged from the low temperature side compressor (121). This low-temperature side refrigerant flows into the secondary side of the cascade heat exchanger (111) through the discharge side check valve (122). In the cascade heat exchanger (111), the low-temperature side refrigerant on the secondary side releases heat to the high-temperature side refrigerant on the primary side and condenses. The low-temperature side refrigerant condensed in the cascade heat exchanger (111) flows into the receiver (123). Thereafter, the low-temperature side refrigerant flows out of the receiver (123), passes through the third liquid side communication pipe (26), and flows through the refrigeration circuit (13).
0).

In the refrigerating circuit (130), the inflowing low-temperature side refrigerant is reduced in pressure by the refrigerating expansion valve (132) and then flows into the refrigerating heat exchanger (131). In the refrigeration heat exchanger (131),
The low-temperature refrigerant absorbs heat from the air in the freezer and evaporates.
That is, in the freezing heat exchanger (131), the air in the freezer is cooled. The low-temperature side refrigerant evaporated in the refrigeration heat exchanger (131) flows into the low-temperature side cascade circuit (120) through the third gas-side communication pipe (27). Thereafter, the low-temperature side refrigerant is sucked into the low-temperature side compressor (121). The low temperature side compressor (121) compresses the sucked low temperature side refrigerant and discharges it again. In the low-temperature side refrigerant circuit (25), such circulation of the low-temperature side refrigerant is repeated.

<Heating Operation> In the heating operation, in the high-temperature side refrigerant circuit (20), the first indoor heat exchanger (81) is used as a condenser, the outdoor heat exchanger (32) and the second indoor heat exchanger ( 91),
Refrigeration heat exchanger (101) and cascade heat exchanger (11
A refrigeration cycle is performed using 1) as an evaporator. On the other hand, in the low-temperature side refrigerant circuit (25), the cascade heat exchanger (111)
Is used as a condenser, and the refrigeration cycle is performed using the refrigeration heat exchanger (131) as an evaporator. The operation of the low-temperature side refrigerant circuit (25) is the same as that in the cooling operation.

During this heating operation, the four-way switching valve (31) is switched to the state shown by the broken line in FIG. The first indoor expansion valve (82), the second indoor expansion valve (92), the refrigeration expansion valve (102), the cascade expansion valve (112), and the refrigeration expansion valve (13)
2) and the outdoor expansion valve (34) is set to a predetermined opening. The oil return solenoid valve (53), oil equalizing solenoid valve (55), degassing solenoid valve (65), and liquid supply solenoid valve (69) are normally kept closed. It is opened and closed appropriately.

When the compressors (41, 42) of the compression mechanism (40) are operated, the compressed high-temperature side refrigerant is discharged from the compressors (41, 42) to the discharge pipe (44). The discharged high-temperature side refrigerant is
After passing through the four-way switching valve (31), it flows into the first indoor circuit (80) through the first gas side communication pipe (22). The high-temperature refrigerant flowing into the first indoor circuit (80) is supplied to the first indoor heat exchanger (8).
In 1), heat is released to the indoor air and condensed. In the first indoor heat exchanger (81), the indoor air is heated by heat radiation of the high-temperature side refrigerant.

The high-temperature side refrigerant condensed in the first indoor heat exchanger (81) passes through the first indoor expansion valve (82) and flows through the first liquid side communication pipe (21). The high-temperature side refrigerant of the first liquid side communication pipe (21) passes through the first liquid side closing valve (35), and flows into the second branch pipe (60b) of the inflow pipe (60). This high temperature side refrigerant is
It flows into the receiver (33) through the inflow check valve (61b). The high-temperature side refrigerant of the receiver (33) flows from the receiver (33) into the outflow pipe (62). Thereafter, the high-temperature side refrigerant is divided into two branches, one of which is the first branch pipe (62a) of the outflow pipe (62).
And the other flows into the second branch pipe (62b) of the outflow pipe (62).

The high-temperature side refrigerant flowing into the first branch pipe (62a) of the outflow pipe (62) is depressurized by the outdoor expansion valve (34), and then flows into the outdoor heat exchanger (32). In the outdoor heat exchanger (32), the high-temperature side refrigerant absorbs heat from outdoor air and evaporates. The evaporated high-temperature side refrigerant flows into the suction pipe (43) through the four-way switching valve (31).

The high-temperature side refrigerant flowing into the second branch pipe (62b) of the outflow pipe (62) flows in the same manner as in the cooling operation. That is, the high-temperature-side refrigerant flows out of the receiver (33), flows through the second liquid-side communication pipe (23), is branched, and is divided into the second indoor circuit (9).
0), refrigeration circuit (100), or high-temperature cascade circuit (11
Sent to 0). The high-temperature side refrigerant flowing into the second indoor circuit (90) absorbs heat from indoor air in the second indoor heat exchanger (91) and evaporates. The high-temperature side refrigerant that has flowed into the refrigeration circuit (100) absorbs heat from the internal air in the refrigeration heat exchanger (101) and evaporates. The high-temperature side refrigerant that has flowed into the high-temperature side cascade circuit (110) absorbs heat from the internal air in the cascade heat exchanger (111) and evaporates. The high-temperature side refrigerant evaporated in the second indoor heat exchanger (91), the refrigeration heat exchanger (101), or the cascade heat exchanger (111) merges in the second gas-side communication pipe (24), and Suction pipe (43) passing through gas side shut-off valve (38)
Flows into

In the suction pipe (43), the high-temperature side refrigerant evaporated in the outdoor heat exchanger (32) and the second indoor heat exchanger (91), the refrigerating heat exchanger (101), or the cascade heat exchanger ( The high-temperature side refrigerant evaporated in 111) merges. The joined high-temperature side refrigerant is sucked into the compressors (41, 42) of the compression mechanism (40).
These compressors (41, 42) compress the drawn high-temperature side refrigerant and discharge it again. In the high-temperature side refrigerant circuit (20), such circulation of the high-temperature side refrigerant is repeated.

As described above, during the heating operation, not only the heat absorbed by the high-temperature side refrigerant from the outdoor air in the outdoor heat exchanger (32) but also the second indoor heat exchanger (91) and the refrigeration heat exchanger (10).
1) Alternatively, the indoor air is heated by the first indoor heat exchanger (81) by utilizing the heat absorbed by the high-temperature side refrigerant from the indoor air or the indoor air in the cascade heat exchanger (111).

During the heating operation, the outdoor heat exchanger (32), the second indoor heat exchanger (91), and the refrigeration heat exchanger (10) are used.
1) and the amount of heat absorbed by the high-temperature refrigerant in the cascade heat exchanger (111) may exceed the amount of heat released by the high-temperature refrigerant in the first indoor heat exchanger (81). In such a case, the outdoor expansion valve (34) is fully closed, and the flow of the high-temperature side refrigerant toward the outdoor heat exchanger (32) is shut off. That is, the second indoor heat exchanger (91), the refrigerating heat exchanger (101), and the cascade heat exchanger (111) are used as evaporators to reduce the amount of heat absorbed by the high-temperature side refrigerant.

<Controller Priority Control Operation> When the operation changeover switch (250) is operated, a predetermined external signal is input to the controller (200). Controller (20
0) performs either the priority control of the second indoor unit (13) or the priority control of the first indoor unit (12) selected by the input external signal.

The priority control of the second indoor unit (13) is a priority control of the cooling system for cooling only, in which the cooling capacity of the second indoor heat exchanger (91) is prioritized during the cooling / heating operation. Therefore, this priority control will be described with reference to FIG.

First, when the control operation of the cooling operation is started, in step ST1, the second internal temperature sensor (94)
And the set temperature Ts of the second indoor unit (13).
It is determined whether or not the state in which the temperature difference from et is smaller than 1 has continued for 10 minutes or more.

If the temperature difference between the detected temperature Tr and the set temperature Tset is smaller than 1 for more than 10 minutes, the evaporation capacity of the second indoor heat exchanger (91) is satisfied.
The process moves to step ST2, executes the control of the LP control routine, and returns.

The detected temperature T of the second inside air temperature sensor (94)
If the temperature difference between r and the set temperature Tset of the second indoor unit (13) is smaller than 1 for less than 10 minutes, the process proceeds from step ST1 to step ST3. In step ST3, the capacity of the compression mechanism (40) is adjusted based on the difference between the detected temperature Tr of the second inside air temperature sensor (94) and the set temperature Tset of the second indoor unit (13). That is, when the difference between the detected temperature Tr and the set temperature Tset is large, the operating frequency Hz of the first compressor (41) is increased.
In this case, since the load is large, the operating frequency Hz of the first compressor (41) is maintained while the second compressor (42) is driven.
Control.

Thereafter, the process proceeds from step ST3 to step ST4, where the operating frequency Hz of the first compressor (41) is set to 2
It is determined whether the state greater than 00 has continued for 10 minutes or more. It is determined whether or not the compression mechanism (40) is continuously operating at the maximum capacity for 10 minutes or more.

If the compression mechanism (40) has been operating for 10 minutes or more at the maximum capacity, the process proceeds from step ST4 to step ST5, and firstly, the air-conditioning air volume reduction unit (211)
Reduces the air volume of the first indoor fan (83). That is,
Since the evaporation capacity of the second indoor heat exchanger (91) is insufficient, the first indoor fan (83) of the first indoor heat exchanger (81).
To reduce the evaporator capacity of the first indoor heat exchanger (81) and increase the evaporative capacity of the second indoor heat exchanger (91). Thereafter, the process returns to step ST1 and repeats the above operation.

If the evaporation capacity of the second indoor heat exchanger (91) is insufficient even after the air-conditioning air volume reduction section (211) reduces the air volume of the first indoor fan (83), the process proceeds to step ST4. From step ST5 to the air-conditioning stop section (21
2) stopping the evaporation of the first indoor heat exchanger (81).
That is, the air-conditioning stop unit (212) suspends the cooling operation of the first indoor unit (12) to perform thermo-off, and increases the evaporation capacity of the second indoor heat exchanger (91). Thereafter, the process returns to step ST1 and repeats the above operation.

Also, in step ST4, the first
If the operating frequency Hz of the compressor (41) is not higher than 200 for more than 10 minutes, the determination is NO because the compressor mechanism (40) is not operating for more than 10 minutes at the maximum capacity. The process moves to step ST6. In this step ST6, the air flow is returned to the original, that is, when the air conditioning stop section (212) thermo-offs the first indoor unit (12), the air flow is returned to the air flow reduction of the air conditioning air flow reduction section (211). , Returning to step ST1, and repeating the above operation.

In step ST6, when the air-conditioning air flow reducing section (211) reduces the air flow of the first indoor fan (83), the air flow of the first indoor fan (83) is returned to the original. , Returning to step ST1, and repeating the above operation.

By the above operation, the second indoor unit (1)
3) The cooling capacity is maintained.

On the other hand, during the heating operation, the same control is performed from step ST1 to step ST4 during the cooling operation. Then, when the compression mechanism (40) is continuously operating at the maximum capacity for 10 minutes or more, the process proceeds from step ST4 to step ST5. First, the air-conditioning air volume increasing unit (213) starts the first indoor heat exchanger ( 81) The air volume of the first indoor fan (83) is increased. That is, since the evaporation capacity of the second indoor heat exchanger (91) is insufficient, the air volume of the first indoor fan (83) of the first indoor heat exchanger (81) is increased to increase the first indoor heat exchanger (81). The condensation capacity of the exchanger (81) is increased, and the evaporation capacity of the second indoor heat exchanger (91) is increased.
Thereafter, the process returns to step ST1 and repeats the above operation.

If the evaporation capacity of the second indoor heat exchanger (91) is insufficient even after the air-conditioning air volume increasing section (213) increases the air volume of the first indoor fan (83), the above-mentioned step ST4 is performed. From step ST5 to the ventilation control section (21
4) increases the air volume of the ventilation fan (87). That is, the ventilation control section (214) takes in outside air into the room, forcibly increases the condensation capacity of the first indoor unit (12),
Increase the evaporation capacity of the indoor heat exchanger (91). afterwards,
Returning to step ST1, the above operation is repeated.

In the above step ST4, the first
If the operating frequency Hz of the compressor (41) is not higher than 200 for more than 10 minutes, the determination is NO because the compressor mechanism (40) is not operating for more than 10 minutes at the maximum capacity. The process moves to step ST6. In this step ST6, the air volume is returned to the original, that is, when the ventilation control unit (214) increases the air volume of the ventilation fan (87), the air volume is returned to the air volume increase of the air conditioning air volume increasing unit (213), Returning to step ST1, the above operation is repeated.

In step ST6, when the air-conditioning air volume increasing unit (213) is increasing the air volume of the first indoor fan (83), the air volume of the first indoor fan (83) is returned to the original. , Returning to step ST1, and repeating the above operation.

By the above operation, the second indoor unit (1
3) The cooling capacity is maintained.

On the other hand, the priority control of the first indoor unit (12) is performed during the cooling operation by the first indoor heat exchanger (81).
This is control of the hepon cooling which gives priority to the cooling capacity of the air conditioner. This priority control is also performed in the second indoor unit (13) described above.
Since the priority control is almost the same as that of the first embodiment, differences will be described with reference to FIG.

In the priority control of the first indoor unit (12), the same control is performed from step ST1 to step ST4 during the cooling operation. Then, when the compression mechanism (40) is continuously operating at the maximum capacity for 10 minutes or more, the process proceeds from step ST4 to step ST5, and first, the cooling air flow reducing unit (221) starts the second indoor fan (9).
3) Reduce the air volume. That is, since the evaporation capacity of the first indoor heat exchanger (81) is insufficient, the air volume of the second indoor fan (93) of the second indoor heat exchanger (91) is reduced to reduce the second indoor heat exchanger (81). The evaporator capacity of the exchanger (91) is reduced, and the evaporative capacity of the first indoor heat exchanger (81) is increased. Thereafter, the process returns to step ST1 and repeats the above operation.

If the evaporation capacity of the first indoor heat exchanger (81) is insufficient even after the cooling air volume reduction section (221) reduces the air volume of the second indoor fan (93), the above step ST4 is performed. From step ST5 to the cooling stop section (22
2) stopping the evaporation of the second indoor heat exchanger (91).
That is, the cooling stop section (222) suspends the cooling operation of the second indoor unit (13) to perform thermo-off, thereby increasing the evaporation capacity of the first indoor heat exchanger (81). Thereafter, the process returns to step ST1 and repeats the above operation.

In step ST4, the first
If the operating frequency Hz of the compressor (41) is not higher than 200 for more than 10 minutes, the determination is NO because the compressor mechanism (40) is not operating for more than 10 minutes at the maximum capacity. The process moves to step ST6. In this step ST6, the air volume is returned to the original, that is, when the cooling stop unit (222) thermo-offs the second indoor unit (13), the air volume is returned to the air volume reduction of the cooling air volume reduction unit (221). , Returning to step ST1, and repeating the above operation.

If the cooling air flow reducing section (221) reduces the air flow of the second indoor fan (93) in step ST6, the air flow of the second indoor fan (93) is restored. , Returning to step ST1, and repeating the above operation.

By the above operation, the first indoor unit (1
2) The cooling capacity is maintained.

<LP Control Operation> Next, the compression mechanism (40) based on the low pressure until the compression mechanism (40) reaches the maximum capacity.
Will be described with reference to FIG.

This LP control controls the operating capacity, which is the capacity of the compression mechanism (40), based on the low pressure LP which is the suction refrigerant pressure of the compression mechanism (40) detected by the low pressure sensor (74). It is.

When increasing the operating capacity of the compression mechanism (40), the second compressor (42) is stopped and
The first compressor (41) is operated from the lowest frequency Hz to the highest frequency Hz.
To increase. Thereafter, the second compressor (42) is driven, and the first compressor (41) is increased from the lowest frequency Hz to the highest frequency Hz.

When the operating capacity of the compression mechanism (40) is reduced, the operation is performed in reverse. When the second compressor (42) is driven, the first compressor (41) is switched from the maximum frequency Hz to the minimum frequency. Reduce to frequency Hz. Thereafter, the second compressor (42) is stopped, and the first compressor (41) is switched to the maximum frequency Hz.
To the lowest frequency Hz.

The control of the compression mechanism (40) is as follows. First, in step ST11, the low pressure LP is set to, for example, 29
It is determined whether it is 4 kPa or less. This low pressure LP is 2
If the pressure is 94 kPa or more, the process proceeds from step ST11 to step ST12, sets the first timer T1 and proceeds to step ST13, and determines whether the zeroth timer T0 has started.

If the 0th timer T0 has not started, the process moves from step ST13 to step ST14.
The operation of the increase routine is performed to increase the operating frequency Hz of the first compressor (41) by a preset frequency. Thereafter, the process proceeds to step ST15, in which the zeroth timer T0 is started, the process proceeds to step ST11, and the above operation is repeated.

Then, the operating frequency H of the first compressor (41)
If the low pressure LP remains at 294 kPa or more even if z is increased, since the 0th timer T0 has been started this time, the determination in step ST13 becomes YES, and the process proceeds to step ST16. It is determined whether the timer T0 has expired. The zeroth timer T0 is set to, for example, 60 seconds, and repeats the above operation until 60 seconds have elapsed. When 60 seconds have elapsed, the process proceeds from step ST16 to step ST14, where the first compressor (41) The operation frequency Hz of the above is increased by a preset frequency. Thereafter, the above operation is repeated.

On the other hand, in step ST11, if the low pressure LP drops below 294 kPa, the determination is NO.
Then, the process proceeds to step ST17 to determine whether the low pressure LP is, for example, 245 kPa or more.

If the low pressure LP is lower than 294 kPa and higher than 245 kPa, the determination in step ST becomes YES, the process moves to step ST11, and the above operation is repeated while maintaining the current state.

When the low pressure LP drops below 245 kPa, the process moves from step ST17 to step ST18, sets the 0th timer T0, moves to step ST19, and determines whether the first timer T1 has started.

If the first timer T1 has not started, the process moves from step ST19 to step ST20,
The operation of the drooping routine is performed to lower the operating frequency Hz of the first compressor (41) by a preset frequency. Thereafter, the process proceeds to step ST21, in which the first timer T1 is started, the process proceeds to step ST11, and the above operation is repeated.

Then, the operating frequency H of the first compressor (41)
If the low pressure LP remains lower than 245 kPa even if z is decreased, the first timer T1 has started this time, so the determination in step ST19 is YES, and the process proceeds to step ST22. It is determined whether or not the timer T1 has expired. This first timer T1 is:
For example, the operation is set to 60 seconds, and the above operation is repeated until 60 seconds elapse. When 60 seconds elapse, the process proceeds from step ST22 to step ST20, and the operating frequency Hz of the first compressor (41) is set in advance. Lower by the set frequency. Thereafter, the above operation is repeated.

The increase routine in step ST14 is as follows.
As shown in FIG. 5, in step ST31, it is determined whether the calculated operating frequency Hz of the first compressor (41), that is, the frequency step is the maximum. If the calculated frequency step is not the maximum frequency step of the first compressor (41), the process proceeds to step ST32, where the frequency step of the first compressor (41) is increased, the process returns to step ST15, and the above operation is repeated. .

If it is determined in step ST31 that the calculated frequency step is the maximum frequency step of the first compressor (41), the process proceeds to step ST33, and the frequency step of the first compressor (41) is changed to the maximum frequency step. And returns to step ST15 to repeat the above operation. Then, in this case, the above-described priority control of the first indoor fan (83) in FIG. 3 and the like is performed.

On the other hand, as shown in FIG. 6, the drooping routine of step ST20 is performed in step ST41.
It is determined whether the calculated operating frequency Hz of the first compressor (41), that is, the frequency step is the lowest. If the calculated frequency step is not the lowest frequency step of the first compressor (41), the process proceeds to step ST42, in which the frequency step of the first compressor (41) is reduced, and the above-mentioned step ST42 is performed.
Returning to step 21, the above operation is repeated.

If it is determined in step ST41 that the calculated frequency step is the lowest frequency step of the first compressor (41), the process proceeds to step ST43, and the frequency step of the first compressor (41) is changed to the lowest frequency step. And returns to step ST21 to repeat the above operation.

The thermo-on control is as shown in FIG. That is, when the first compressor (41) is started while the second compressor (42) is stopped, first, in step ST51, it is determined whether or not a predetermined standby time has elapsed. After waiting for
Move to step ST52, where the low pressure LP is 245 kPa
It is determined whether or not this is the case. Low pressure LP is 245k
The thermo-off state is continued until the pressure becomes equal to or more than Pa.
The process moves from step 52 to step ST53, where the first compressor (41) is started at the lowest frequency step, and the above-described LP control and the like are performed.

That is, when the first compressor (41) has the lowest frequency Hz, the result is as shown in FIG. For example, when the low pressure LP is 98 kPa or less, the first compressor (41)
Stop area. When the low pressure LP is higher than 98 kPa and lower than 245 kPa, the operation range is the lowest frequency Hz of the first compressor (41). Low pressure LP is 245
When the pressure is equal to or higher than kPa and lower than 294 kPa, the operating frequency Hz of the first compressor (41) does not change. When the low pressure LP is 294 kPa or more, a continuous region for 60 seconds corresponds to a rising region where the operating frequency Hz of the first compressor (41) is increased.

If the first compressor (41) is not at the lowest frequency Hz, the result is as shown in FIG. For example, when the low pressure LP is lower than 245 kPa, a drooping region where the operating frequency Hz of the first compressor (41) is lowered for 60 seconds consecutively. When the low pressure LP is 245 kPa or more, 2
When the pressure is lower than 94 kPa, the operating frequency Hz of the first compressor (41) does not change. Low pressure LP is 294
kPa or more, the first compressor (4
This is an ascending region where the operation frequency Hz in 1) is increased.

<Effects of Embodiment> As described above, according to the present embodiment, priority control of the second indoor heat exchanger (91) or priority control of the first indoor heat exchanger (81) can be performed. As a result, it is possible to perform control corresponding to the user's request without fail, and to improve comfort.

Further, since the first indoor heat exchanger (81) and the second indoor heat exchanger (91) are controlled in relation to each other, the capacity of the compression mechanism (40) can be set small. As a result, the entire apparatus can be made inexpensive.

[0142]

In the above embodiment, the low-temperature side refrigerant circuit (25) is provided. However, in the present invention, the low-temperature side refrigerant circuit (25) is not necessarily required to be provided.

In the present invention, when the low-temperature side refrigerant circuit (25) is provided, the refrigerator unit (14) may not be provided.

Further, according to the present invention, the compression mechanism (40) includes the first
It may have only the compressor (41).

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram illustrating a refrigerant circuit of a refrigeration apparatus according to an embodiment of the present invention.

FIG. 2 is a refrigerant circuit diagram showing a low-temperature side refrigerant circuit according to the embodiment of the present invention.

FIG. 3 is a control flowchart showing priority control according to the present invention.

FIG. 4 is a control flowchart showing LP control of a compression mechanism.

FIG. 5 is a control flowchart showing a routine for increasing the operating frequency of the compression mechanism.

FIG. 6 is a control flowchart showing a drooping routine of an operating frequency of a compression mechanism.

FIG. 7 is a control flow chart showing thermo-on control of a compression mechanism.

FIG. 8 is a characteristic diagram showing an operation range in the compression mechanism of the lowest frequency.

FIG. 9 is a characteristic diagram showing an operation range of the compression mechanism having the lowest frequency or higher.

[Explanation of symbols]

 10 Refrigeration unit 32 Outdoor heat exchanger (heat source side heat exchanger) 40 Compression mechanism 41 First compressor 42 Second compressor 81 First indoor heat exchanger (air-conditioning heat exchanger) 83 First indoor fan (air-conditioning fan) 87 Ventilation fan (ventilation means) 91 2nd indoor heat exchanger (cooling heat exchanger) 92 2nd indoor fan (cooling fan) 101 Refrigeration heat exchanger (cooling heat exchanger) 131 Refrigeration heat exchanger (cooling heat) 210) Air-conditioning capacity control means 211 Cooling capacity control means 212 Air-conditioning air volume reduction unit 213 Air-conditioning stop unit 214 Ventilation control unit 220 Cooling capacity control unit 221 Cooling air volume reduction unit 222 Cooling stop unit

Continuation of the front page (72) Inventor Kenji Tanimoto 1304 Kanaokacho, Sakai City, Osaka Prefecture Daikin Industries, Ltd. Sakai Seisakusho Kanaoka Plant F-term (reference) 3L060 AA08 CC02 DD02 EE05 3L061 BE02 BF02 3L092 GA01 GA12 HA10 JA12 KA05 KA05 KA13 LA05 LA07

Claims (7)

[Claims] 1. A compression mechanism (40) and a heat source side heat exchanger (32).
And an air conditioning heat exchanger (81) for cooling and heating the room, a cooling heat exchanger (91) for cooling only the room, and a cooling heat exchanger (101) for cooling the inside of the refrigerator , Condensing the refrigerant in the heat source side heat exchanger (32)
1), a cooling cycle for evaporating the refrigerant in the cooling only heat exchanger (91) and the cooling heat exchanger (101), and an air conditioning heat exchanger (81)
A refrigerant circuit (1A) that switches between a heating cycle for condensing refrigerant and a heating cycle for evaporating refrigerant in the cooling heat exchanger (91) and a cooling heat exchanger (101), and the maximum capacity of the compression mechanism (40) Sometimes the air conditioning heat exchanger (8
(1) A refrigerating apparatus comprising: capacity control means (210, 220) for giving priority to controlling the evaporation capacity of the cooling-specific heat exchanger (91). 2. The air-conditioning heat exchanger according to claim 1, wherein the capacity control means (210) is configured to determine if the evaporation capacity of the cooling-specific heat exchanger (91) is insufficient at the maximum capacity of the compression mechanism (40) in the cooling cycle. A refrigeration apparatus comprising an air-conditioning air flow reduction unit (211) for reducing the air volume of the air-conditioning fan (83) of (81). 3. The capacity control means (210) according to claim 2, wherein the air-conditioning air flow reducing section (211) reduces the air flow of the air-conditioning fan (83) even after the air-conditioning fan (83) has reduced the air flow. A refrigeration system comprising an air conditioning stop (212) for stopping evaporation of the air conditioning heat exchanger (81) when the capacity is insufficient. 4. The air-conditioning heat exchanger according to claim 3, wherein the capacity control means (210) is configured to determine if the evaporation capacity of the cooling-specific heat exchanger (91) is insufficient at the maximum capacity of the compression mechanism (40) in the heating cycle. A refrigeration system comprising an air conditioning air volume increasing section (213) for increasing the air volume of the air conditioning fan (83) of (81). 5. The capacity control means (210) according to claim 4, further comprising a ventilation means (87) for ventilating a room in which the air conditioning heat exchanger (81) is installed. Even after increasing the air volume of the air-conditioning fan (83), if the evaporation capacity of the cooling-specific heat exchanger (91) is insufficient, the ventilation means (8
7) A refrigeration apparatus comprising the ventilation control section (214) for increasing the air volume. 6. The cooling-only heat exchanger according to claim 1, wherein the capacity control means (220) is provided when the evaporating capacity of the air-conditioning heat exchanger (81) is insufficient at the maximum capacity of the compression mechanism (40) in the cooling cycle. A refrigeration apparatus comprising: a cooling air flow reducing section (221) for reducing the air flow of a cooling fan (93) of (91). 7. The evaporating capacity of the air conditioning heat exchanger (81) according to claim 6, wherein the capacity control means (220) is configured to reduce the air volume of the cooling fan (93) even after the cooling air volume reduction section (221) reduces the air volume. A refrigeration system comprising a cooling stop section (222) for stopping evaporation of the cooling only heat exchanger (91) when the temperature is insufficient.