JP2010112639A - Multiple chamber air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an operation control method of a multiple chamber air conditioner capable of effectively recovering oil to an intake side and being appropriately operated without becoming short in capacity. <P>SOLUTION: In this multiple chamber air conditioner, main and sub oil separators 3a, 3b are disposed between a discharge pipe 1a of a compressor 1 and a four-way valve 2, the sub oil separator 3b is connected by an electromagnetic two-way valve 4 and a check valve 5, the main and sub oil separators 3a, 3b are connected to an intake pipe 1b of the compressor 1 via a capillary tube 6, discharge gas is made to flow in the main and sub oil separators 3a, 3b by opening the electromagnetic two-way valve 4 during start control of the compressor 1, and when the compressor discharge temperature exceeds a prescribed set value, the electromagnetic two-way valve 4 is closed and the discharge gas is made to flow into only the main oil separator 3a. During start control of the compressor 1, a refrigerant is made to flow into both the main and sub oil separators 3a, 3b so that the refrigerant and the oil are separated and the oil is recovered to the low pressure side, and a decrease of an oil level in the compressor 1 can be prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an operation control method for a multi-room air conditioner.

  A conventional operation control method for this type of multi-room air conditioner will be described with reference to FIG. FIG. 17 is a refrigeration cycle diagram of a multi-room air conditioner employing a conventional multi-room air conditioner operation control method. 51 is a compressor, 52 is a four-way valve, 54 is an outdoor heat exchanger, 55 Is an outdoor blower, 56 is an outside air temperature sensor, 57 is an expansion valve, 58 is an indoor heat exchanger, 59 is an indoor blower, 60 is an indoor piping temperature sensor, and 61 is an indoor suction temperature sensor.

An oil separator 53 is connected between the discharge pipe 51a and the suction pipe 51b of the compressor 51 via a capillary tube 62. Here, when the compressor 51 is started, the oil is discharged together with the refrigerant, but is separated into the refrigerant and the oil in the oil separator 53, and the oil is recovered to the suction pipe 51b via the capillary tube 62. Since the oil further passes through the accumulator 63 from the suction pipe 51b and is finally recovered in the shell of the compressor 51, the oil level in the shell of the compressor 51 can be prevented (for example, patent) Reference 1).
JP 2002-31387 A

  However, in the above conventional multi-chamber air conditioner, the discharge pipe 51a and the suction pipe 51b are connected via the capillary tube 62, but at the time of start-up or the like, the refrigerant and the oil are mutually melted and separated. However, the refrigerant and the oil cannot be sufficiently separated with only a single oil separator, and not only the oil but also the refrigerant flows from the discharge pipe 51a toward the suction pipe 51b. For this reason, there is a problem that the loss of capacity is large, and the cooling or heating capacity is insufficient, which causes discomfort to the user.

  The present invention solves the above-described conventional problems, and can efficiently recover only oil to the suction pipe side without lowering the capacity, thereby enabling proper operation without being in a state of insufficient capacity. An object is to provide a multi-room air conditioner.

In order to solve the above-described conventional problems, a multi-room air conditioner of the present invention is an air including a compressor, an oil separator, a four-way valve, an outdoor heat exchanger, and a plurality of indoor heat exchangers. In the conditioner, at least two main and sub oil separators are arranged in parallel in the compressor, and the sub oil separator includes an electromagnetic two-way valve and a check valve before and after the main and sub oil separators. The oil separator is connected to the suction pipe of the compressor via a decompression device, and when the cooling or heating operation is started and during the start-up control of the compressor, the electromagnetic two-way valve is opened to discharge the discharge gas. Control that causes the main and sub oil separators to flow, closes the electromagnetic two-way valve when the discharge temperature of the compressor exceeds a predetermined set value, and causes the discharge gas to flow only to the main oil separator With this configuration, the discharge temperature of the compressor reaches a predetermined set value when the cooling or heating operation is started and the compressor is operating at a low frequency during start-up control. Until the electromagnetic two-way valve is opened and the refrigerant flows into both the main and sub oil separators, the ability to separate the refrigerant and the oil is sufficiently increased, and the separated oil is recovered to the low pressure side and the compressor The internal oil level is prevented from lowering, and after the start-up control is finished, the compressor discharge temperature reaches the set value.
By limiting the operating oil separator to the main oil separator and preventing the refrigerant from flowing into the sub oil separator, the oil separator capacity is increased only when necessary, and decreased when not needed to demonstrate the optimal oil separator capacity. The air conditioning capacity can be maximized.

  The multi-room air conditioner of the present invention can eliminate a decrease in the oil level of the compressor at the start of cooling or heating operation, and can prevent a decrease in cooling / heating capacity.

  A first invention is an air conditioner comprising a compressor, an oil separator, a four-way valve, an outdoor heat exchanger, and a plurality of indoor heat exchangers, wherein the oil separator of the compressor is a main and a sub At least two are arranged in parallel, and the sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after the sub oil separator, and the main and sub oil separators are connected to a suction pipe of the compressor via a pressure reducing device. When the cooling or heating operation is started and the compressor start-up control is started, the electromagnetic two-way valve is opened, and the discharge gas is circulated through the main and sub oil separators, and the discharge temperature of the compressor Is provided with a control unit that closes the electromagnetic two-way valve and distributes the discharge gas only to the main oil separator when the value exceeds a predetermined set value. Alternatively, when the compressor is operating at a low frequency at the start of heating operation and during start-up control, the electromagnetic two-way valve is opened until the discharge temperature of the compressor reaches a predetermined set value, and the refrigerant By flowing into both the main and sub oil separators to fully demonstrate the ability to separate the refrigerant and oil, separating the refrigerant and oil, and recovering to the low pressure side, reducing the oil level inside the compressor After the start-up control is completed, after the compressor discharge temperature reaches a predetermined set value, the electromagnetic two-way valve is closed to prevent refrigerant from flowing into the sub-oil separator, thereby maximizing the capacity. It can be used for proper air conditioning operation.

  2nd invention is the air provided with the compressor, the discharge pressure detection apparatus which detects the discharge pressure of the said compressor, the oil separator, the four-way valve, the outdoor heat exchanger, and the some indoor heat exchanger. In the conditioner, the oil separator of the compressor is disposed in parallel with at least two of the main and sub, and the sub oil separator includes an electromagnetic two-way valve and a check valve before and after the main and sub, and the main and sub The sub oil separator is connected to the suction pipe of the compressor via a pressure reducing device, and when the cooling or heating operation is started and during the start-up control of the compressor, the electromagnetic two-way valve is opened to discharge the discharge gas to the main When the discharge pressure detected by the discharge pressure detection device exceeds a predetermined set value, the electromagnetic two-way valve is closed and the discharge gas is allowed to flow into the main oil separator. With this configuration, the compressor discharges when the compressor is operating at a low frequency at the start of cooling or heating operation and during start-up control. Until the pressure reaches a predetermined set value, the electromagnetic two-way valve is opened, and the refrigerant is allowed to flow into both the main and sub oil separators, so that the ability to separate the refrigerant and the oil is sufficiently exerted. The oil is separated and recovered to the low-pressure side to prevent the oil level in the compressor from decreasing. After the start-up control is completed, the compressor's discharge pressure reaches the set value, and the electromagnetic two-way valve is closed. Thus, by preventing the refrigerant from flowing into the sub-oil separator, the capacity can be maximized and proper air-conditioning operation can be performed.

According to a third aspect of the present invention, there is provided an air conditioner comprising a compressor, an oil separator, a four-way valve, an outdoor heat exchanger, a plurality of indoor heat exchangers, and a refrigerant condensation temperature detection device, wherein the compressor The oil separator is disposed in parallel with at least two of the main and sub, the sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after the oil separator, and the main and sub oil separators are provided with a pressure reducing device. The compressor is connected to the suction pipe of the compressor, and at the start of the cooling or heating operation and during the start-up control of the compressor, the electromagnetic two-way valve is opened and the discharge gas is circulated to the main and sub oil separators. When the condensation temperature detected by the condensation temperature detection device exceeds a predetermined set value, the electromagnetic two-way valve is closed and the discharge gas is allowed to flow only to the main oil separator. With this configuration, when the compressor is operating at a low frequency at the start of cooling or heating operation and during start-up control, the refrigerant condensing temperature is set to a predetermined set value. Until reaching the above, by opening the electromagnetic two-way valve and allowing the refrigerant to flow into both the main and sub-oil separators, the refrigerant and the oil are separated by sufficiently exerting the ability to separate the refrigerant and the oil, By recovering to the low pressure side, the oil level in the compressor is prevented from lowering. After the start-up control is completed, the refrigerant two-way valve is closed after the condensing temperature of the refrigerant reaches a predetermined set value, and the refrigerant is sub-oil separator. By preventing it from flowing in, it is possible to maximize the capacity and perform proper air conditioning operation.

  4th invention is equipped with the compressor, the discharge superheat degree detection apparatus which detects the discharge superheat degree of the said compressor, an oil separator, a four-way valve, an outdoor heat exchanger, and several indoor heat exchangers. In the air conditioner, at least two oil separators of the main and sub are arranged in parallel, and the sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after the main oil separator, And the sub-oil separator is connected to the suction pipe of the compressor via a pressure reducing device, and when the cooling or heating operation is started and during the start-up control of the compressor, the electromagnetic two-way valve is opened to discharge gas. When the compressor and the sub oil separator are circulated and the discharge superheat degree of the compressor exceeds a predetermined set value, the electromagnetic two-way valve is closed and the discharge gas is supplied only to the main oil separator. With this configuration, the discharge superheat degree of the compressor can be reduced when the compressor is operating at a low frequency at the start of cooling or heating operation and during start-up control. Until the predetermined set value is reached, the electromagnetic two-way valve is opened, and the refrigerant flows into both the main and sub oil separators, so that the ability to separate the refrigerant and the oil is fully exerted, and the refrigerant and the oil Is separated and recovered to the low pressure side to prevent the oil level inside the compressor from decreasing. After the start-up control is completed, the discharge superheat of the compressor reaches the set value, and then close the electromagnetic two-way valve. By preventing the refrigerant from flowing into the sub-oil separator, the capacity can be maximized and proper air conditioning operation can be performed.

  A fifth invention is an air conditioner comprising a compressor, an oil separator, a four-way valve, an outdoor heat exchanger, a plurality of indoor heat exchangers, and an outdoor air temperature detection device, wherein the oil of the compressor The separator is arranged in parallel with at least two of the main and sub, the sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after the separator, and the main and sub oil separators are connected via a pressure reducing device. Connected to the suction pipe of the compressor, at the start of cooling or heating operation and during the start-up control of the compressor, the electromagnetic two-way valve is opened to allow the discharge gas to flow through the main and sub oil separators, When the outside air temperature detected by the outside air temperature detecting device exceeds a predetermined set value, the electromagnetic two-way valve is closed and the discharge gas is circulated only to the main oil separator. With this configuration, when the compressor is operating at a low frequency at the start of cooling or heating operation and during start-up control, until the outside air temperature reaches a predetermined set value, By opening the electromagnetic two-way valve and allowing the refrigerant to flow into both the main and sub oil separators, the refrigerant and the oil are separated sufficiently and recovered to the low pressure side. This prevents the oil level in the compressor from decreasing and closes the electromagnetic two-way valve so that the refrigerant does not flow to the sub oil separator after the outside air temperature reaches a predetermined set value after the start control is completed. Therefore, it is possible to perform the proper air conditioning operation by maximizing the ability.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a refrigeration cycle diagram of a multi-room air conditioner according to a first embodiment of the present invention.

  In FIG. 1, the multi-room air conditioner in the present embodiment is composed of one outdoor unit (not shown) and a plurality of indoor units (not shown) connected to the outdoor unit (see FIG. 1). 1 is a single indoor unit), the outdoor unit is a variable capacity compressor 1, a four-way valve 2, and a main oil separator disposed between the compressor 1 and the four-way valve 2. 3a, sub oil separator 3b, electromagnetic two-way valve 4, check valve 5, capillary tube 6 for oil return and also a pressure reducing device, outdoor heat exchanger 7, outdoor blower 8, and outdoor temperature sensor 9 And the main expansion valve 10. The indoor unit includes an indoor heat exchanger 11, an indoor blower 12, an indoor piping temperature sensor 13, and an indoor suction temperature sensor 14.

  The main oil separator 3 a is connected between the discharge pipe 1 a and the suction pipe 1 b of the compressor 1 via the capillary tube 6. The sub oil separator 3b has a four-way valve 2 and an electromagnetic two-way valve 4 before and after the sub-oil separator 3b, and between the discharge pipe 1a and the suction pipe 1b of the compressor 1 via the electromagnetic two-way valve 4. The main oil separator 3a is connected in parallel.

  FIG. 2 is a control block diagram of the multi-room air conditioner in the present embodiment.

  In FIG. 2, 31 is an operation mode detection device that detects cooling, heating, and other operation modes, 32 is a compressor operation frequency detection device, 33 is an expansion valve opening detection device that detects the opening of the main expansion valve 10, and 34. Is an expansion valve opening degree storage device, 35 is a compressor discharge temperature detection device, 36 is a compressor discharge temperature storage device, 37 is an expansion valve drive device for the sub oil separator 3b, and 300 is a control unit.

  The operation and action of the multi-room air conditioner based on this control block diagram will be described below using the flowchart of FIG. 3 and the time chart of FIG.

  The control unit 300 operates at the start-up frequency Hz1 at the start of the cooling or heating operation and during the start-up control. At this time, the electromagnetic two-way valve 4 for the sub oil separator 3b is opened. This is because at the start of sleep, the amount of oil dissolved in the refrigerant is large and it is determined that the main oil separator 3a alone is not sufficient to separate the refrigerant and oil, and the refrigerant flows to the sub oil separator 3b. This is because the refrigerant and the oil are separated by sufficiently exerting the ability to separate the refrigerant and the oil using 3b. As a result, the refrigerant and the oil can be separated efficiently and the oil can be recovered to the low pressure side, and the oil level inside the compressor 1 can be prevented from being lowered.

  Next, even during the start-up control, when the compressor discharge temperature rises and reaches the set value Td1, the control unit 300 closes the electromagnetic two-way valve 4 so that the refrigerant does not flow into the sub oil separator 3b. To do. This is because the oil is easily separated from the refrigerant when the temperature of the refrigerant rises, and the oil can be efficiently recovered to the low pressure side only by the main oil separator 3a. As a result, the oil level can be prevented from being lowered, and at the same time, the air conditioning capability can be efficiently exhibited.

(Embodiment 2)
FIG. 5 is a control block diagram of the multi-room air conditioner according to the second embodiment of the present invention, FIG. 6 is a flowchart showing operation control of the multi-room air conditioner, and FIG. 7 is the multi-room air conditioner. It is a time chart which shows the operation control of a machine. In addition, about the same part as the multi-room type air conditioner in the said Embodiment 1, the description is abbreviate | omitted using the same code | symbol.

5-7, 38 is a discharge pressure detection apparatus which detects the discharge pressure of the compressor 1, 39 is a discharge pressure memory | storage device, 300 is a control part. The operation of the sub oil separator 3b will be described with reference to these drawings. The control unit 300 operates the compressor at the activation frequency Hz1 at the start of cooling or heating operation and during the activation control. At this time, the two-way solenoid valve 4 for the sub oil separator 3b is opened. This is for the same reason as in the first embodiment. At the time of stagnation start-up, the amount of oil dissolved in the refrigerant is large, and it is determined that the main oil separator 3a alone does not sufficiently separate the refrigerant and the oil. The refrigerant also flows to the separator 3b, fully demonstrates the ability to separate the refrigerant and oil, efficiently separates the refrigerant and oil, and recovers the oil to the low pressure side, thereby reducing the oil level inside the compressor 1 Is to prevent.

  Next, even during the start-up control, when the discharge pressure of the compressor 1 detected by the discharge pressure detection device 38 increases and reaches the set value Pd1, the control unit 300 controls the two-way valve 4 of the solenoid valve. Prevent the refrigerant from flowing into the closed sub-oil separator. This is because if the pressure of the refrigerant rises, the oil is easily separated from the refrigerant, so that the oil can be efficiently recovered to the low pressure side using only the main oil separator 3a. As a result, the oil level can be prevented from being lowered, and at the same time, the air conditioning capability can be efficiently exhibited.

(Embodiment 3)
FIG. 8 is a control block diagram of the multi-room air conditioner according to the third embodiment of the present invention, FIG. 9 is a flowchart showing operation control of the multi-room air conditioner, and FIG. 10 is the multi-room air conditioner. It is a time chart which shows the operation control of a machine. In addition, about the same part as the multi-room air conditioner in the said embodiment, the description is abbreviate | omitted using the same code | symbol.

  8 to 10, reference numeral 40 denotes a condensing temperature detecting device for detecting the condensing temperature of the refrigerant, 41 denotes a condensing temperature storage device, and 300 denotes a control unit. The controller 300 operates the compressor at the start-up frequency Hz1 at the start of cooling or heating operation and during start-up control. At this time, the electromagnetic two-way valve 4 for the sub oil separator 3b is opened. This is also due to the same reason as in the previous embodiments, and at the time of stagnation start-up, the amount of oil dissolved in the refrigerant is large and it is determined that the main oil separator 3a alone does not sufficiently separate the refrigerant and oil, The refrigerant flows through the sub-oil separator 3b, fully demonstrates the ability to separate the refrigerant and the oil, efficiently separates the refrigerant and the oil, and collects the oil to the low pressure side. This is to prevent a decrease.

  Next, even during start-up control, when the condensing temperature of the refrigerant detected by the condensing temperature detector 40 rises and reaches the set value Thp1, the control unit 300 closes the electromagnetic two-way valve 4 and sub-oil. The refrigerant is prevented from flowing into the separator 3b. Assuming that the refrigerant condensing temperature is equal to the discharge pressure, the oil is easily separated from the refrigerant when the discharge pressure is increased. Therefore, the oil can be efficiently recovered to the low pressure side only by the main oil separator 3a. As a result, the oil level can be prevented from being lowered, and at the same time, the air conditioning capability can be efficiently exhibited.

(Embodiment 4)
FIG. 11 is a control block diagram of the multi-room air conditioner according to the fourth embodiment of the present invention, FIG. 12 is a flowchart showing operation control of the multi-room air conditioner, and FIG. 13 is the multi-room air conditioner. It is a time chart which shows the operation control of a machine. In addition, about the same part as the multi-room air conditioner in the said embodiment, the description is abbreviate | omitted using the same code | symbol.

  11-13, 42 is a discharge superheat degree detection apparatus which detects the discharge superheat degree of the compressor 1, 43 is a discharge superheat degree memory | storage device, 300 is a control part. The controller 300 operates the compressor at the start-up frequency Hz1 at the start of cooling or heating operation and during start-up control.

At this time, the electromagnetic two-way valve 4 for the sub oil separator 3b is opened. In the same manner as in the previous embodiments, it is determined that the amount of oil dissolved in the refrigerant is large at the time of start-up and only the main oil separator 3a determines that the separation of the refrigerant and the oil is insufficient, and the refrigerant is sent to the sub oil separator 3b. This is to prevent the lowering of the oil level inside the compressor 1 by sufficiently separating the refrigerant and the oil and recovering the oil to the low pressure side by sufficiently exhibiting the ability to separate the refrigerant and the oil by flowing the refrigerant. .

  Next, even during start-up control, when the discharge superheat degree of the compressor 1 detected by the discharge superheat degree detection device 42 increases and reaches the set value SH1, the control unit 300 performs the electromagnetic two-way valve 4. Is closed so that the refrigerant does not flow into the sub oil separator 3b. Here, if the discharge superheat degree of the compressor 1 is high, it is determined that the discharge gas has already been separated from the oil, and the oil can be efficiently recovered to the low pressure side only by the main oil separator 3a. As a result, the oil level can be prevented from being lowered, and at the same time, the air conditioning capability can be efficiently exhibited.

(Embodiment 5)
FIG. 14 is a control block diagram of the multi-room air conditioner according to the fifth embodiment of the present invention, FIG. 15 is a flowchart showing operation control of the multi-room air conditioner, and FIG. 16 is the multi-room air conditioner. It is a time chart which shows the operation control of a machine. In addition, about the same part as the multi-room air conditioner in the said embodiment, the description is abbreviate | omitted using the same code | symbol.

  14-16, 44 is an outside temperature detection apparatus which detects outside temperature, 45 is an outside temperature memory | storage device, 300 is a control part. The controller 300 operates the compressor at the start-up frequency Hz1 at the start of cooling or heating operation and during start-up control.

  At this time, the electromagnetic two-way valve 4 for the sub oil separator 3b is opened. Similarly to the previous embodiments, at the time of stagnation start-up, it is determined that the amount of oil dissolved in the refrigerant is large and the main oil separator 3a alone is not sufficient to separate the refrigerant and oil, and the refrigerant is sent to the sub oil separator 3b. This is to prevent the lowering of the oil level inside the compressor 1 by sufficiently separating the refrigerant and the oil by efficiently flowing the refrigerant and separating the refrigerant and the oil and recovering the oil to the low pressure side.

  Next, even during the start-up control, the controller 300 closes the electromagnetic two-way valve 4 when the outside air temperature detected by the outside air temperature detecting device 44 rises and reaches the set value To1, and the sub oil separator Prevent the refrigerant from flowing into 3b. This is because if the outside air temperature is high, the discharge pressure rises and it is determined that the discharge gas is already separated from the oil, and the oil can be efficiently recovered to the low pressure side only by the main oil separator 3a. As a result, the oil level can be prevented from being lowered, and at the same time, the air conditioning capability can be efficiently exhibited.

  As described above, the multi-room air conditioner according to the present invention can efficiently recover the compressor oil without deteriorating the cooling or heating capacity. It can also be used for machine oil recovery control.

Refrigeration cycle diagram of the multi-chamber air conditioner in the first embodiment of the present invention Control block diagram showing operation control of the multi-room air conditioner Flow chart showing operation control of the multi-room air conditioner Time chart showing operation control of the multi-room air conditioner Control block diagram of the multi-room air conditioner in the second embodiment of the present invention Flow chart showing operation control of the multi-room air conditioner Time chart showing operation control of the multi-room air conditioner Control block diagram of multi-room air conditioner in the third embodiment of the present invention Flow chart showing operation control of the multi-room air conditioner Time chart showing operation control of the multi-room air conditioner Control block diagram of multi-room air conditioner in the fourth embodiment of the present invention Flow chart showing operation control of the multi-room air conditioner Time chart showing operation control of the multi-room air conditioner Control block diagram of multi-room air conditioner in fifth embodiment of the present invention Flow chart showing operation control of the multi-room air conditioner Time chart showing operation control of the multi-room air conditioner Refrigeration cycle diagram of a conventional multi-room air conditioner

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 4 way valve 3a Main oil separator 3b Sub oil separator 4 Electromagnetic 2 way valve 5 Check valve 6 Capillary tube (pressure reduction device)
7 Outdoor Heat Exchanger 8 Outdoor Blower 9 Outdoor Air Temperature Sensor 10 Main Expansion Valve 35 Compressor Discharge Temperature Detection Device 36 Compressor Discharge Temperature Storage Device 38 Discharge Pressure Detection Device 39 Discharge Pressure Storage Device 40 Condensation Temperature Detection Device 41 Condensation Temperature Storage Device 42 Discharge superheat degree detection device 43 Discharge superheat degree storage device 44 Outside air temperature detection device 45 Outside air temperature storage device

Claims (5)

In an air conditioner including a compressor, an oil separator, a four-way valve, an outdoor heat exchanger, and a plurality of indoor heat exchangers, at least two of the main and sub oil separators are arranged in parallel. The sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after the sub oil separator, and the main and sub oil separators are connected to a suction pipe of the compressor via a pressure reducing device, for cooling or heating. At the start of operation and during start-up control of the compressor, the electromagnetic two-way valve is opened, the discharge gas is circulated through the main and sub oil separators, and the discharge temperature of the compressor has a predetermined set value. A multi-chamber air conditioner provided with a control unit that closes the electromagnetic two-way valve when exceeded and distributes the discharge gas only to the main oil separator. In the air conditioner including a compressor, a discharge pressure detection device that detects a discharge pressure of the compressor, an oil separator, a four-way valve, an outdoor heat exchanger, and a plurality of indoor heat exchangers, the compression The oil separator of the machine is disposed in parallel with at least two of the main and sub, the sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after that, and the main and sub oil separators are pressure reducing devices. Is connected to the suction pipe of the compressor via the valve, and at the start of cooling or heating operation and during start-up control of the compressor, the electromagnetic two-way valve is opened to discharge gas to the main and sub oil separators. When the discharge pressure detected by the discharge pressure detection device exceeds a predetermined set value, the electromagnetic two-way valve is closed and the discharge gas is supplied only to the main oil separator. A multi-room air conditioning apparatus characterized by comprising a control unit for pass. In an air conditioner comprising a compressor, an oil separator, a four-way valve, an outdoor heat exchanger, a plurality of indoor heat exchangers, and a refrigerant condensation temperature detection device, the oil separator of the compressor is the main and At least two subs are arranged in parallel, the sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after the sub oil separator, and the main and sub oil separators are connected to the compressor via a pressure reducing device. Connected to the suction pipe, and when starting the cooling or heating operation and during the start-up control of the compressor, the electromagnetic two-way valve is opened and the discharge gas is circulated to the main and sub oil separators to detect the condensation temperature. When the condensing temperature detected by the apparatus exceeds a predetermined set value, the electromagnetic two-way valve is closed, and a control unit is provided to distribute the discharge gas only to the main oil separator. Multi-room air conditioning apparatus according to claim and. In an air conditioner comprising a compressor, a discharge superheat detection device that detects a discharge superheat degree of the compressor, an oil separator, a four-way valve, an outdoor heat exchanger, and a plurality of indoor heat exchangers, The oil separator of the compressor is arranged in parallel with at least two main and sub, the sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after that, and the main and sub oil separators are The compressor is connected to a suction pipe of the compressor via a pressure reducing device, and at the start of cooling or heating operation and during startup control of the compressor, the electromagnetic two-way valve is opened to discharge gas from the main and sub oils. When the discharge superheat degree of the compressor exceeds a predetermined set value, the electromagnetic two-way valve is closed and the discharge gas is allowed to flow only to the main oil separator. A multi-room air conditioning apparatus characterized by comprising a part. In an air conditioner including a compressor, an oil separator, a four-way valve, an outdoor heat exchanger, a plurality of indoor heat exchangers, and an outdoor air temperature detection device, the oil separator of the compressor is a main and a sub At least two of them are arranged in parallel, the sub oil separator is provided with an electromagnetic two-way valve and a check valve before and after the sub oil separator, and the main and sub oil separators are connected to a suction pipe of the compressor via a pressure reducing device. When the cooling or heating operation is started and the start-up control of the compressor is being performed, the electromagnetic two-way valve is opened to circulate the discharge gas to the main and sub oil separators, and the outside air temperature detection device When the detected outside air temperature exceeds a predetermined set value, the electromagnetic two-way valve is closed, and a control unit is provided to distribute the discharge gas only to the main oil separator. Multi-room air conditioner and butterflies.

Images