WO2022075248A1

WO2022075248A1 - Outdoor air conditioning apparatus

Info

Publication number: WO2022075248A1
Application number: PCT/JP2021/036586
Authority: WO
Inventors: 伸哉村井; 高幹山本
Original assignee: ダイキン工業株式会社
Priority date: 2020-10-08
Filing date: 2021-10-04
Publication date: 2022-04-14
Also published as: JP2022062471A

Abstract

The present invention presents an air conditioning apparatus with which it is possible to prevent the compressor oil quantity from falling below a required quantity in a compressor (10) in association with outdoor use. This outdoor air conditioning apparatus (100) is used outdoors, the apparatus (100) comprising a refrigerant circuit (20) and a control device (70). The refrigerant circuit (20) has a compressor (10), a heat-source-side heat exchanger (40), and a use-side heat exchanger (30). In the refrigerant circuit (20), a refrigerant circulates through the compressor (10), the heat-source-side heat exchanger (40), and the use-side heat exchanger (30), whereby a refrigeration cycle is carried out. The control device (70) activates the compressor (10) and executes a refrigeration cycle operation for causing the refrigerant circuit (20) to carry out the refrigeration cycle. The control device (70): executes a first pre-operation control (first control) in which, after the compressor (10) is activated for a prescribed first period, the compressor (10) is stopped for a prescribed second period that is longer than the first period; and initiates the refrigeration cycle operation after the first pre-operation control has ended.

Description

Outdoor air conditioner

Regarding outdoor air conditioners.

An air conditioner in which a compressor, a heat exchanger on the user side, and a heat exchanger on the heat source side are housed in one housing is known.

Patent Document 1 (Japanese Unexamined Patent Publication No. 2020-003182) describes outdoor air in which a compressor, a heat source side heat exchanger, a first fan, a user side heat exchanger, and a second fan are housed in a casing. The harmonizer is disclosed.

The outdoor air conditioner disclosed in Patent Document 1 has a problem that the amount of compressor oil in the compressor falls below the required amount after the start of the refrigeration cycle operation due to being placed in a low temperature environment for a long period of time such as at night. Specifically, a phenomenon called forming occurs in which the refrigerant condensed due to the temperature drop and dissolved in the compressor oil in the compressor is vaporized by the temperature rise caused by the drive of the compressor to foam the compressor oil. As a result, the compressor oil foamed together with the refrigerant is discharged from the compressor, and the amount of the compressor oil in the compressor is reduced, so that the amount of the compressor oil may be less than the required amount.

The present disclosure proposes an air conditioner capable of suppressing the amount of compressor oil from falling below the required amount in a compressor due to outdoor use.

The outdoor air conditioner of the first aspect is an air conditioner used outdoors, and includes a refrigerant circuit and a control unit. The refrigerant circuit has a compressor, a heat source side heat exchanger, and a user side heat exchanger, and the refrigerating cycle is performed by circulating the refrigerant through the compressor, the heat source side heat exchanger, and the user side heat exchanger. Let me do it. The control unit activates the compressor and executes a refrigerating cycle operation in which the refrigerant circuit is allowed to perform the refrigerating cycle. The control unit executes the first control and starts the refrigeration cycle operation after the first control is completed. The first control starts the compressor for a predetermined first period and then stops the compressor for a predetermined second period longer than the first period.

According to the outdoor air conditioner of the first aspect, the compressor is started for the first period and the temperature inside the compressor rises, so that the refrigerant dissolved in the compressor oil is vaporized and separated from the compressor oil. Is discharged from. Further, by stopping the compressor for the second period, the difference between the refrigerant pressure in the heat source side heat exchanger and the refrigerant pressure in the user side heat exchanger becomes small, and the refrigerant diffuses from the high pressure side to the low pressure side. Be promoted. As a result, even if the refrigeration cycle operation is started after the first control, the amount of the compressor oil is suppressed from falling below the required amount due to the discharge of the compressor oil together with the refrigerant.

The outdoor air conditioner of the second viewpoint is the outdoor air conditioner of the first viewpoint, and the first period is 1 second or more and 20 seconds or less.

The outdoor air conditioner of the third viewpoint is the outdoor air conditioner of the first viewpoint or the second viewpoint, and the second period is 1 minute or more and 20 minutes or less.

The outdoor air conditioner according to the fourth aspect is the outdoor air conditioner according to any one of the first aspect to the third aspect, and the refrigerant circuit is a switching mechanism for switching between the first state and the second state. Has. In the first state, the refrigerant is circulated in the order of the compressor, the heat source side heat exchanger, and the user side heat exchanger. In the second state, the refrigerant is circulated in the order of the compressor, the heat exchanger on the user side, and the heat exchanger on the heat source side. In the first control, the control unit sets the switching mechanism in the first state while the compressor is running, and sets the switching mechanism in the second state in the refrigeration cycle operation. Alternatively, in the first control, the control unit sets the switching mechanism in the second state while the compressor is running, and sets the switching mechanism in the first state in the refrigeration cycle operation.

According to the outdoor air conditioner of the fourth aspect, the refrigerant separated in the compressor in the first control is discharged toward the heat exchanger on the low pressure side in the subsequent refrigeration cycle operation. Therefore, even if the refrigerant discharged from the compressor contains compressor oil, the compressor oil contained in the refrigerant can be quickly returned to the compressor after the start of the refrigeration cycle operation, so that the amount of compressor oil increases. It is possible to effectively suppress the amount from falling below the required amount.

The outdoor air conditioner of the fifth aspect is the outdoor air conditioner of the fourth aspect, and the control unit sets the switching mechanism in the first state in the first control and the switching mechanism in the second state in the refrigeration cycle operation. And. Alternatively, the control unit sets the switching mechanism in the second state in the first control and the switching mechanism in the first state in the refrigeration cycle operation.

The outdoor air conditioner of the sixth viewpoint is any of the outdoor air conditioners of the first to fifth viewpoints, and the compressor has a constant refrigerant discharge capacity per unit time.

A non-inverter compressor with a constant refrigerant discharge capacity per unit time can be manufactured at low cost, but the discharge capacity cannot be finely controlled. Therefore, in an outdoor air conditioner having a non-inverter compressor, the compressor reaches the maximum rotation speed at the time of starting, intense forming occurs in the compressor, and the amount of compressor oil tends to be less than the required amount. According to the outdoor air conditioner of the sixth aspect, even when a compressor (non-inverter compressor) having a constant refrigerant discharge capacity per unit time is used as the compressor, the amount of compressor oil is required. It is possible to suppress the amount from falling below the amount.

The outdoor air conditioner of the 7th viewpoint is any of the outdoor air conditioners of the 1st to 6th viewpoints, and the heat source side heat exchanger is arranged above the user side heat exchanger.

The outdoor air conditioner according to the eighth aspect is the outdoor air conditioner according to any one of the first to seventh aspects, and the heat source side heat exchanger and the user side heat exchanger are above the compressor. Have been placed.

In an outdoor air conditioner in which the heat source side heat exchanger and the user side heat exchanger are arranged above the compressor, the heat source side heat exchanger and the refrigerant condensed in the user side heat exchanger are used. It is easy for a large amount to flow into the inside of the compressor. In particular, in the case of an integrated air conditioner in which the heat exchanger on the user side and the heat exchanger on the heat source side are housed in one casing, compared with the separate type air conditioner in which these are housed in another casing. This tendency is remarkable because the suction pipe provided between the heat exchanger on the user side and the compressor and the second gas connecting pipe tend to be shortened. According to the outdoor air conditioner of the eighth aspect, the amount of compressor oil in the compressor is less than the required amount even when the heat source side heat exchanger and the user side heat exchanger are arranged above the compressor. This can be suppressed by simple control. Therefore, there is a high degree of freedom in design regarding the arrangement of the heat source side heat exchanger, the user side heat exchanger, and the compressor.

The outdoor air conditioner according to the ninth aspect is the outdoor air conditioner according to any one of the first aspect to the eighth aspect, and further includes a crankcase heater that heats the compressor oil of the compressor by generating heat. The control unit executes the first control after starting the second control for heating the crankcase heater.

According to the outdoor air conditioner of the ninth aspect, the heat generated by the crankcase heater heats the refrigerant dissolved in the compressor oil, so that the amount of the refrigerant dissolved in the compressor oil can be further reduced.

The outdoor air conditioner of the tenth viewpoint is the outdoor air conditioner of the ninth viewpoint, and the control unit continues the second control until the refrigeration cycle operation is started.

The 11th viewpoint outdoor air conditioner is the 9th or 10th viewpoint outdoor air conditioner, further including a timer and an indicator. The timer measures the elapsed time since the crankcase heater started to generate heat. The instruction unit transmits an execution instruction instructing the control unit to execute the refrigeration cycle operation. The control unit starts the second control when the power is turned on, and when it receives an execution instruction from the instruction unit, it compares the elapsed time with the predetermined third time. If the elapsed time is equal to or longer than the predetermined third period, the control unit starts the refrigeration cycle operation without executing the first control. Further, if the elapsed time is less than the third period, the control unit executes the first control and starts the refrigeration cycle operation after the first control is completed.

According to the 11th viewpoint outdoor air conditioner, the time from receiving the execution instruction from the instruction unit to starting the refrigeration cycle operation can be shortened, and the convenience is improved.

It is an external perspective view of the outdoor air conditioner 100 of 1st Embodiment. It is a figure which shows schematically the refrigerant circuit 20 of the outdoor air conditioner 100. It is a perspective view which shows the internal structure of the casing 90 of the outdoor air conditioner 100. It is a schematic side view which shows the internal structure of the casing 90 of the outdoor air conditioner 100. It is a schematic plan view of the heat exchanger 40 on the heat source side of the outdoor air conditioner 100. It is a schematic plan view of the heat exchanger 30 on the user side of the outdoor air conditioner 100. It is a flowchart which shows the control flow of the 1st pre-operation control executed by the control device 70 of the outdoor air conditioner 100. It is a flowchart which shows the control flow of the 1st pre-operation control which concerns on modification 1A. It is a flowchart which shows the control flow of the 1st pre-operation control which concerns on modification 2A. It is a figure which shows schematically the refrigerant circuit 20 of the outdoor air conditioner 101. It is a flowchart which shows the control flow of the 2nd pre-operation control executed by the control device 71 of the outdoor air conditioner 101. It is a flowchart which shows the control flow of the 3rd pre-operation control executed by the control device 71 of the outdoor air conditioner 101. It is a graph which shows the movement of a compressor in an Example, and the oil level behavior of a compressor oil.

<First Embodiment>
The outdoor air conditioner 100 according to the first embodiment will be described below with reference to the drawings.

In the following, expressions such as "top", "bottom", "front (front)", "rear (back)", "left", and "right" may be used to explain the position and direction. Unless otherwise specified, these expressions follow the directions of the "up", "down", "front", "rear", "left", and "right" arrows shown in the drawings.

(1) Overall Overview FIG. 1 is an external perspective view of the outdoor air conditioner 100. FIG. 2 is a diagram schematically showing a refrigerant circuit 20 of the outdoor air conditioner 100.

The outdoor air conditioner 100 is an air conditioner that is installed outdoors and performs air conditioning outdoors. Here, the outdoor means a space where at least a part is exposed to the outside air. Outdoors include places without roofs or walls, such as parks, open-air stadiums, and the like. However, the outdoors are not limited to roofs and places without walls, such as open-air spaces with roofs, open terraces, places like Azumaya, and courtyards without roofs surrounded by walls. Includes spaces that are at least partly open to the outside, such as places that are open to the public.

The outdoor air conditioner 100 performs outdoor cooling, dehumidification, heating, and the like by utilizing a steam compression refrigeration cycle (hereinafter, simply referred to as a refrigeration cycle) performed in the refrigerant circuit 20. The refrigerant used in the outdoor air conditioner 100 is not limited, but is, for example, R32 alone or a mixed refrigerant containing R32. Specific examples of the mixed refrigerant containing R32 include R452B, R410A, R454B, and an HFO mixed refrigerant. R452B is a mixed refrigerant containing 67.0 wt% of R32, 7.0 wt% of R125, and 26.0 wt% of R1234yf. R410A is a mixed refrigerant containing 50 wt% of R32 and 50 wt% of R125. R454B is a mixed refrigerant containing 72.5 wt% of R32 and 27.5 wt% of R1234yf. The HFO mixed refrigerant contains 45.0 wt% of HFO-1123 and 55.0 wt% of R32, and also contains 40.0 wt% of HFO-1123 and 60.0 wt% of R32. Further, the refrigerant used in the outdoor air conditioner 100 may be a natural refrigerant such as CO ₂ .

In the present embodiment, the outdoor air conditioner 100 is a device capable of performing a cooling / dehumidifying operation and a heating operation, which are refrigeration cycle operations. Although the details will be described later, the outdoor air conditioner 100 is the first operation for suppressing the amount of compressor oil in the compressor 10 (described later) due to outdoor use from falling below the required amount before executing the refrigeration cycle operation. Perform pre-control. However, the outdoor air conditioner 100 is not limited to a device capable of performing cooling / dehumidifying operation and heating operation. For example, the outdoor air conditioner 100 may be a dedicated cooling machine capable of performing only cooling / dehumidifying operation. Further, for example, the outdoor air conditioner 100 may be a dedicated heating machine capable of performing only heating operation. When the outdoor air conditioner 100 is a dedicated cooling machine, the outdoor air conditioner 100 does not have to have the switching mechanism 12 described later. Further, even when the outdoor air conditioner 100 is a dedicated heating machine, the outdoor air conditioner 100 does not have to have the switching mechanism 12.

As shown in FIG. 2, the outdoor air conditioner 100 is a refrigerant in which devices such as a compressor 10, a switching mechanism 12, a user-side heat exchanger 30, an expansion mechanism 16, and a heat source-side heat exchanger 40 are connected by a pipe. It has a circuit 20. The outdoor air conditioner 100 accommodates the entire refrigerant circuit 20 in the casing 90. Further, the outdoor air conditioner 100 includes a user-side fan 50 that generates an air flow so that air passes through the user-side heat exchanger 30, and a heat source that generates an air flow so that air passes through the heat source-side heat exchanger 40. It has a side fan 60 and. The user-side fan 50 and the heat source-side fan 60 are housed in the casing 90. The operation of the outdoor air conditioner 100 is controlled by the control device 70 based on the execution instruction from the instruction unit 80.

(2) Detailed Description The casing 90, the refrigerant circuit 20, the user-side fan 50, the heat source-side fan 60, the control device 70, and the indicator 80 will be described below. The refrigerant circuit 20 includes a compressor 10, a switching mechanism 12, a heat source side heat exchanger 40, a utilization side heat exchanger 30, and an expansion mechanism 16.

(2-1) Casing The casing 90 of the outdoor air conditioner 100 and the arrangement of the equipment in the casing 90 will be described below with reference to the drawings.

FIG. 3 is a perspective view showing the internal configuration of the casing 90 of the outdoor air conditioner 100. FIG. 3 depicts the outdoor air conditioner 100 in a state where the decorative plate 91 of the casing 90 and some of the columns (supports 92b) are removed, and depicts the arrangement of the devices inside the casing 90. .. FIG. 4 is a schematic side view showing the internal configuration of the casing 90 of the outdoor air conditioner 100. FIG. 4 shows a cross section of a part of the configurations (utility side heat exchanger 30, heat source side heat exchanger 40, utilization side fan 50, etc.).

In the outdoor air conditioner 100 of the present embodiment, the casing 90 houses the compressor 10, the user-side heat exchanger 30, the heat source-side heat exchanger 40, the user-side fan 50, and the heat source-side fan 60. In the present embodiment, the casing 90 has a substantially rectangular parallelepiped shape having a substantially square shape in a plan view. However, the shape of the casing 90 is not limited to a substantially rectangular parallelepiped shape having a substantially square shape in a plan view, and may have a rectangular parallelepiped shape having a rectangular shape in a plan view. Further, the casing 90 may have a polygonal prism shape having a polygonal shape in a plan view, and may have a cylindrical shape having a circular shape in a plan view or an elliptical pillar shape having an elliptical view. The shape of the casing 90 may be appropriately determined.

Preferably, casters 95 are attached to the lower surface of the casing 90, and the outdoor air conditioner 100 is configured to be movable.

(2-1-1) The column, the top plate, and the bottom plate casing 90 have four columns 92a to 92d, a top plate 94, and a bottom plate 96.

The four columns 92a to 92d are arranged so as to extend in the vertical direction at the four corners of the casing 90 having a substantially square shape in a plan view. The top plate 94 and the bottom plate 96 are fixed to the four columns 92a to 92d. The top plate 94 is formed with an exhaust port 84 at the center thereof for discharging the air that has passed through the heat source side heat exchanger 40 to the outside of the casing 90. That is, the top plate 94 is formed with an exhaust port 84 at the center thereof for discharging the air that has exchanged heat with the refrigerant flowing through the heat source side heat exchanger 40 to the outside of the casing 90. A mesh-shaped fan guard (not shown) is arranged above the exhaust port 84. On the bottom plate 96, a compressor 10, an electrical component box 2 containing various electrical components of the outdoor air conditioner 100, and the like are installed.

(2-1-2)

Drain Pans

36, 46 are arranged inside the casing 90 to partition the inside of the casing 90.

The drain pan 46 is arranged below the heat source side heat exchanger 40 and adjacent to the heat source side heat exchanger 40. Here, the fact that the drain pan 46 is arranged adjacent to the lower part of the heat source side heat exchanger 40 means that the member is arranged between at least a part of the lower end of the heat source side heat exchanger 40 and the drain pan 46. It means that it has not been done.

The drain pan 46 is fixed to the columns 92a to 92d. The drain pan 46 is a member having a bottom portion 46a and a side wall 46b extending upward from the peripheral edge of the bottom portion 46a. The drain pan 46 receives dew condensation water, rainwater, and the like generated by the heat source side heat exchanger 40. The drain pan 46 is not limited to a material, but is, for example, a metal member.

The drain pan 46 partitions the heat source area A1 arranged above the drain pan 46 and the use area A2 arranged below the drain pan 46. Due to the drain pan 46, the air immediately after passing through the heat source side heat exchanger 40 may directly flow into the utilization area A2, or the air immediately after passing through the utilization side heat exchanger 30 may directly flow into the heat source area A1. It is suppressed. That is, the drain pan 46 suppresses the direct inflow of the air in the heat source area A1 into the utilization area A2 and the direct inflow of the air in the utilization area A2 into the heat source area A1. The drain pan 46 also functions as a member for heat insulation between the air flow path FP that has passed through the utilization side heat exchanger 30 and the heat source side heat exchanger 40. The drain pan 46 also functions as a member for heat insulation between the air flow path FP that has passed through the utilization side heat exchanger 30 and the air flow path that has passed through the heat source side heat exchanger 40. A support member 47 that supports the user-side fan 50 is arranged below the drain pan 46.

The drain pan 36 is arranged below the user-side heat exchanger 30 and adjacent to the user-side heat exchanger 30. Here, the fact that the drain pan 36 is arranged adjacent to the lower side of the user side heat exchanger 30 means that the member is arranged between at least a part of the lower end of the user side heat exchanger 30 and the drain pan 36. It means that it has not been done.

The drain pan 36 is fixed to the columns 92a to 92d. The drain pan 36 is a member having a bottom portion 36a and a side wall 36b extending upward from the peripheral edge of the bottom portion 36a. The drain pan 36 receives dew condensation water, rainwater, and the like generated by the heat exchanger 30 on the user side. The drain pan 36 is not limited to a material, but is, for example, a metal member.

The drain pan 36 partitions the use area A2 arranged above the drain pan 36 and the machine room area A3 arranged below the drain pan 36.

(2-1-3) Heat source area, utilization area, and machine room area In the heat source area A1, a heat source side heat exchanger 40 and a heat source side fan 60 are mainly arranged. In the heat source area A1, a heat source side heat exchanger 40 is arranged above the drain pan 46 and adjacent to the drain pan 46. The heat source side heat exchanger 40 is arranged adjacent to the bottom portion 46a of the drain pan 46. Further, in the heat source area A1, a heat source side fan 60 is arranged above the heat source side heat exchanger 40.

The user side heat exchanger 30 and the user side fan 50 are mainly arranged in the use area A2. The used area A2 is further divided into a blowout area A21 arranged above the intermediate plate 98 and a heat exchanger area A22 arranged below the intermediate plate 98 by the intermediate plate 98 fixed to the columns 92a to 92d. It is partitioned.

The user side fan 50 is mainly arranged in the blowout area A21. In the blowout area A21, a flow path FP for air that has passed through the heat exchanger 30 on the utilization side is formed.

In the flow path FP of the air that has passed through the user side heat exchanger 30 (hereinafter, may be simply referred to as the flow path FP), an outlet through which the air that has passed through the user side heat exchanger 30 is blown out to the outside of the casing 90. 82 is included. The outlet 82 is formed between adjacent columns on the side surface of the casing 90 surrounding the outlet area A21. The outlet 82 includes a plurality of outlets 82a to 82d (four in this embodiment). Specifically, the outlet 82a is formed between the support column 92a and the support column 92b (on the right side surface). An outlet 82b is formed between the support column 92b and the support column 92c (front surface). An outlet 82c is formed between the support column 92c and the support column 92d (left side surface). An outlet 82d is formed between the support column 92d and the support column 92a (rear surface).

The air that has exchanged heat with the refrigerant in the user-side heat exchanger 30 passes through the flow path FP and is blown out of the casing 90 from the outlets 82a to 82d of the flow path FP. Here, since the outlets 82a to 82d are formed on the four side surfaces of the casing 90, the air that has passed through the flow path FP is blown out from the casing 90 in a plurality of directions (in all directions).

The outlets 82a to 82d are arranged between the heat source side heat exchanger 40 and the user side heat exchanger 30. The outlets 82a to 82d are located below the heat source side heat exchanger 40 and above the utilization side heat exchanger 30.

In the heat exchanger area A22, the user-side heat exchanger 30 is arranged above the drain pan 36 and adjacent to the drain pan 36. The user-side heat exchanger 30 is arranged adjacent to the bottom portion 36a of the drain pan 36.

In the machine room area A3, a compressor 10 and an electrical component box 2 containing various electrical components of the outdoor air conditioner 100 are mainly arranged.

(2-1-4) Decorative board A decorative board 91 is attached to the side surface of the casing 90 so as to close between adjacent columns. Specifically, on the side surface of the casing 90, between the support column 92a and the support column 92b, between the support column 92b and the support column 92c, between the support column 92c and the support column 92d, between the support column 92d, and the support column. A decorative plate 91 is attached so as to close the space between the 92a and the 92a.

The veneer 91 has a first veneer 91a, a second veneer 91b, and a third veneer 91c.

The first decorative plate 91a is attached to the casing 90 so as to close between adjacent columns on the outside of the heat source area A1. The second decorative plate 91b is attached to the casing 90 so as to close between the lower side of the blowout area A21, the heat exchanger area A22, and the adjacent columns outside the machine room area A3. The third decorative plate 91c is attached to the casing 90 so as to close the space between the adjacent columns on the outer side of the upper side of the blowout area A21. The outlets 82a to 82d are closed above the second decorative plate 91b and by the third decorative plate 91c.

A plurality of through holes are formed in the decorative plate 91 in a mesh shape, and air can flow through the through holes. As will be described later, the air taken into the casing 90 from the outside by the heat source side fan 60 and the user side fan 50 is a through hole formed in the first decorative plate 91a and the second decorative plate 91b (not shown). ) And flows into the inside from the outside of the casing 90. The air blown from the outlets 82a to 82d by the user-side fan 50 to the outside of the casing 90 passes through the lower side of the second decorative plate 91b and the through holes formed in the third decorative plate 91c, and is inside the casing 90. Blow out from.

(2-1-5) Piping space In the outdoor air conditioner 100, heat exchange from the machine room area A3 to the heat source side adjacent to at least one of four columns 92a to 92d (supports 92b in this embodiment). It is preferable that a piping space PS extending upward to the height position of the vessel 40 is formed. In the piping space PS, connecting

pipes

20c, 20d, 20e and the like, which will be described later, are arranged. In order to form the piping space PS, one corner of the drain pan 46 having a substantially square shape is cut out. In the present embodiment, in order to form the piping space PS, the corner portion of the drain pan 46 arranged adjacent to the support column 92b is cut out. The same applies to the drain pan 36. It is preferable that the piping space PS is separated from the space through which the airflow generated by the heat source side fan 60 and the user side fan 50 passes by the

partition plates

99a, 99b, 99c extending in the vertical direction. As a result, the inflow of air from the heat source area A1 and the utilization area A2 into the piping space PS is suppressed.

(2-2) Refrigerant circuit As described above, the outdoor air conditioner 100 is connected to equipment such as the compressor 10, the switching mechanism 12, the user side heat exchanger 30, the expansion mechanism 16, and the heat source side heat exchanger 40. It has a refrigerant circuit 20 connected by.

Here, the connection of equipment in the refrigerant circuit 20 will be described. The outdoor air conditioner 100 mainly includes a suction pipe 20a, a discharge pipe 20b, a first gas connecting pipe 20c, a liquid connecting pipe 20d, and a second gas as pipes for connecting the equipment constituting the refrigerant circuit 20. Including the connecting pipe 20e.

The suction pipe 20a connects the switching mechanism 12 and the pipe connection portion (not shown) on the suction side of the compressor 10. The suction tube 20a has, for example, an inner diameter of 12.7 mm and a length of 803 mm.

The discharge pipe 20b connects the pipe connection portion (not shown) on the discharge side of the compressor 10 and the switching mechanism 12. The discharge pipe 20b has, for example, an inner diameter of 7.9 mm and a length of 1265 mm.

The first gas connecting pipe 20c connects the switching mechanism 12 and the gas side refrigerant inlet / outlet of the heat source side heat exchanger 40. The first gas connecting pipe 20c has, for example, an inner diameter of 12.7 mm and a length of 1440 mm.

The liquid communication pipe 20d connects the liquid side refrigerant inlet / outlet of the heat source side heat exchanger 40 and the liquid side refrigerant inlet / outlet of the user side heat exchanger 30. An expansion mechanism 16 is arranged in the liquid communication pipe 20d.

The second gas connecting pipe 20e connects the gas side refrigerant inlet / outlet of the user side heat exchanger 30 and the switching mechanism 12. The second gas connecting pipe 20e has, for example, an inner diameter of 12.7 mm and a length of 1024 mm.

(2-3) Compressor The compressor 10 is a device that compresses the refrigerant. The compressor 10 compresses the low pressure refrigerant in the refrigeration cycle and pressurizes it to the high pressure in the refrigeration cycle.

The type of the compressor 10 is not limited, but is, for example, a rotary type or scroll type positive displacement compressor. The compression mechanism (not shown) of the compressor 10 is driven by the motor 11. The compressor 10 is a non-inverter compressor (non-inverter compressor) in which the motor 11 is rotationally driven at a constant speed and the refrigerant is discharged at a constant capacity. However, the present invention is not limited to this, and the compressor may be a compressor having a variable capacity (inverter compressor). The compressor 10 is filled with a predetermined amount of compressor oil.

An accumulator may be provided on the suction side (suction pipe 20a) of the compressor 10 in order to suppress the inflow of the liquid refrigerant into the compressor 10.

(2-4) Switching Mechanism The switching mechanism 12 switches the flow direction of the refrigerant discharged from the compressor 10 to change the operating state of the outdoor air conditioner 100 into a first operating state and a second operating state. It is a mechanism to switch between. In the first operating state, the user-side heat exchanger 30 is made to function as an evaporator, and the heat source-side heat exchanger 40 is made to function as a condenser (radiator). In the second operating state, the user-side heat exchanger 30 is made to function as a condenser (radiator), and the heat source-side heat exchanger 40 is made to function as an evaporator.

The switching mechanism 12 switches the operating state of the outdoor air conditioner 100 to the first operating state during the cooling / dehumidifying operation. Specifically, during the cooling / dehumidifying operation, the switching mechanism 12 communicates the suction pipe 20a with the second gas connecting pipe 20e and the discharge pipe 20b with the first gas connecting pipe 20c (switching mechanism 12 in FIG. 2). See the solid line inside). That is, the switching mechanism 12 communicates the suction side of the compressor 10 with the gas side end of the user side heat exchanger 30 through the suction pipe 20a and the second gas connecting pipe 20e during the cooling / dehumidifying operation, and compresses the compressor 10. The discharge side of the machine 10 is communicated with the gas side end of the heat source side heat exchanger 40 through the discharge pipe 20b and the first gas connecting pipe 20c. Therefore, when the operating state of the outdoor air conditioner 100 is the first operating state, the refrigerant circulates in the refrigerant circuit 20 in the order of the compressor 10, the heat source side heat exchanger 40, and the user side heat exchanger 30. Hereinafter, the state of the switching mechanism 12 during the cooling / dehumidifying operation is referred to as a first state.

The switching mechanism 12 switches the operating state of the outdoor air conditioner 100 to the second operating state during the heating operation. Specifically, during the heating operation, the switching mechanism 12 communicates the suction pipe 20a with the first gas connecting pipe 20c and the discharge pipe 20b with the second gas connecting pipe 20e (in the switching mechanism 12 of FIG. 2). See dashed line). That is, the switching mechanism 12 communicates the suction side of the compressor 10 with the gas side end of the heat source side heat exchanger 40 through the suction pipe 20a and the first gas connecting pipe 20c during the heating operation, and the compressor 10 Is communicated with the gas side end of the user side heat exchanger 30 through the discharge pipe 20b and the second gas connecting pipe 20e. Therefore, when the operating state of the outdoor air conditioner 100 is in the second operating state, the refrigerant circulates in the refrigerant circuit 20 in the order of the compressor 10, the user side heat exchanger 30, and the heat source side heat exchanger 40. .. Hereinafter, the state of the switching mechanism 12 during the heating operation is referred to as a second state.

In the present embodiment, the switching mechanism 12 is a four-way switching valve. However, the switching mechanism 12 is not limited to the four-way switching valve, and may be configured so as to be able to realize the switching of the flow direction of the refrigerant as described above by combining a plurality of solenoid valves and a refrigerant pipe. ..

(2-5) Heat Source Side Heat Exchanger The heat source side heat exchanger 40 is a heat exchanger that exchanges heat between a refrigerant and outdoor air. When the operating state of the outdoor air conditioner 100 is in the first operating state, the heat source side heat exchanger 40 functions as a condenser. When the operating state of the outdoor air conditioner 100 is in the second operating state, the heat source side heat exchanger 40 functions as an evaporator. In the present embodiment, the heat source side heat exchanger 40 is arranged above the user side heat exchanger 30. Further, the heat source side heat exchanger 40 is arranged above the compressor 10.

In the heat source side heat exchanger 40, the liquid connecting pipe 20d is connected to the liquid side end, and the first gas connecting pipe 20c is connected to the gas side end.

The heat source side heat exchanger 40 is a fin-and-tube heat exchanger mainly having a refrigerant heat transfer tube 43 in which a refrigerant flows inside and a large number of heat transfer fins (not shown). As shown in FIGS. 3 and 4, the heat source side heat exchanger 40 is arranged above the drain pan 46 and adjacent to the drain pan 46. The lower end of the heat source side heat exchanger 40 is preferably arranged below the upper end of the side wall 46b of the drain pan 46.

Condensation water generated in the heat source side heat exchanger 40 when the heat source side heat exchanger 40 functions as an evaporator, water generated when the frost adhering to the heat source side heat exchanger 40 is melted during the defrost operation described later, and exhaust Rainwater or the like flowing in from the mouth 84 or the like flows into the drain pan 46. The water flowing into the drain pan 46 is formed, for example, inside at least one of the columns 92a to 92d, or is arranged adjacent to at least one of the columns 92a to 92d through a drainage path (not shown). , Discharged from the bottom of the outdoor air conditioner 100.

As shown in FIG. 4, the heat source side heat exchanger 40 has a heat exchange unit 41a and a heat exchange unit 41b. In each of the

heat exchange portions

41a and 41b, the refrigerant heat transfer tubes 43 are arranged in a direction intersecting the direction of the airflow Fb from the outside of the casing 90 toward the inside of the casing 90, which is generated by the heat source side fan 60. In the present embodiment, the refrigerant heat transfer tubes 43 are arranged in the vertical direction in each of the

heat exchange portions

41a and 41b. In the heat source side heat exchanger 40, the heat exchange unit 41a and the heat exchange unit 41b are arranged side by side in two rows in the direction of the air flow Fb generated by the heat source side fan 60. In other words, in the heat source side heat exchanger 40 of the heat source side heat exchanger 40, the refrigerant heat transfer tubes 43 arranged in the vertical direction are arranged in two rows in the direction of the air flow Fb generated by the heat source side fan 60. The heat exchange unit 41a is arranged on the downstream side in the direction of the air flow Fb generated by the heat source side fan 60, and the heat exchange unit 41b is arranged on the upstream side in the direction of the air flow Fb generated by the heat source side fan 60.

FIG. 5 is a schematic plan view of the heat source side heat exchanger 40 of the outdoor air conditioner 100. As shown in FIG. 5, the heat source side heat exchanger 40 is arranged so as to form a quadrilateral shape in a plan view. As a result, in the heat source side heat exchanger 40, the refrigerant heat transfer tube 43 forms a plurality of heat exchange surfaces HSb1 to HSb4 through which the airflow Fb generated by the heat source side fan 60 passes. The heat exchange surfaces HSb1 to HSb4 are arranged adjacent to the decorative plate 91 of the casing 90. It is preferable that no other member is arranged between the heat exchange surfaces HSb1 to HSb4 of the heat source side heat exchanger 40 and the decorative plate 91. The heat exchange surface HSb1 is arranged on the rear side of the outdoor air conditioner 100 and spreads in the vertical direction and the horizontal direction. The heat exchange surface HSb2 is arranged on the right side of the outdoor air conditioner 100 and spreads in the vertical direction and the front-back direction. The heat exchange surface HSb3 is arranged on the front side of the outdoor air conditioner 100 and spreads in the vertical direction and the horizontal direction. The heat exchange surface HSb4 is arranged on the left side of the outdoor air conditioner 100 and spreads in the vertical direction and the front-back direction.

When the heat source side fan 60 is operated, the air taken in from the outside of the casing 90 through the through hole (not shown) of the first decorative plate 91a by the air flow Fb generated by the heat source side fan 60 is on the heat source side. It passes through the heat exchange surfaces HSb1 to HSb4 of the heat exchanger 40. The air that has passed through the heat exchange surfaces HSb1 to HSb4 exchanges heat with the refrigerant flowing inside the refrigerant heat transfer tube 43 of the heat source side heat exchanger 40. The air that has exchanged heat with the refrigerant in the heat source side heat exchanger 40 is formed on the upper part of the casing 90 by passing through the bell mouth 64 arranged in the upper part in the casing 90 by the air flow Fb generated by the heat source side fan 60. It is exhausted upward from the exhaust port 84.

(2-6) User-side heat exchanger The user-side heat exchanger 30 is a heat exchanger that exchanges heat between the refrigerant and the outdoor air. When the operating state of the outdoor air conditioner 100 is in the first operating state, the user-side heat exchanger 30 functions as an evaporator. When the operating state of the outdoor air conditioner 100 is in the second operating state, the user-side heat exchanger 30 functions as a condenser. In the present embodiment, the user-side heat exchanger 30 is arranged above the compressor 10.

In the user-side heat exchanger 30, the liquid connecting pipe 20d is connected to the liquid side end, and the second gas connecting pipe 20e is connected to the gas side end.

The user-side heat exchanger 30 is a fin-and-tube heat exchanger having a refrigerant heat transfer tube 33 through which a refrigerant flows, and a large number of heat transfer fins (not shown). As shown in FIGS. 3 and 4, the user-side heat exchanger 30 is arranged above the drain pan 36 and adjacent to the drain pan 36. It is preferable that the lower end of the user-side heat exchanger 30 is arranged below the upper end of the side wall 36b of the drain pan 36.

When the user-side heat exchanger 30 functions as an evaporator, dew condensation water or the like generated in the user-side heat exchanger 30 flows into the drain pan 36. The water flowing into the drain pan 36 is formed, for example, inside at least one of the columns 92a to 92d, or is arranged adjacent to at least one of the columns 92a to 92d through a drainage path (not shown). , Discharged from the bottom of the outdoor air conditioner 100.

As shown in FIG. 4, the user-side heat exchanger 30 has a heat exchange unit 31a and a heat exchange unit 31b (see FIG. 4). In each of the

heat exchange portions

31a and 31b, the refrigerant heat transfer tubes 33 are arranged in a direction intersecting the direction of the airflow Fa from the outside of the casing 90 toward the inside of the casing 90, which is generated by the user-side fan 50. In the present embodiment, the refrigerant heat transfer tubes 33 are arranged in the vertical direction in each of the

heat exchange portions

31a and 31b. In the user side heat exchanger 30, the heat exchange unit 31a and the heat exchange unit 31b are arranged side by side in two rows in the direction of the air flow Fa generated by the user side fan 50. In other words, in the user-side heat exchanger 30 of the user-side heat exchanger 30, the refrigerant heat transfer tubes 33 arranged in the vertical direction are arranged in two rows in the direction of the air flow Fa generated by the user-side fan 50. The heat exchange unit 31a is arranged on the downstream side in the direction of the airflow Fa generated by the user-side fan 50, and the heat exchange unit 31b is arranged on the upstream side in the direction of the airflow Fa generated by the user-side fan 50.

FIG. 6 is a schematic plan view of the heat exchanger 30 on the user side of the outdoor air conditioner 100. As shown in FIG. 6, the utilization side heat exchanger 30 is arranged so as to form a quadrilateral shape in a plan view. As a result, in the user-side heat exchanger 30, the refrigerant heat transfer tube 33 forms a plurality of heat exchange surfaces HSa1 to HSa4 through which the airflow Fa generated by the user-side fan 50 passes. The heat exchange surfaces HSa1 to HSa4 of the user-side heat exchanger 30 are arranged adjacent to the decorative plate 91 of the casing 90. It is preferable that no other member is arranged between the heat exchange surfaces HSa1 to HSa4 of the user-side heat exchanger 30 and the decorative plate 91. The heat exchange surface HSa1 is arranged on the rear side of the outdoor air conditioner 100 and spreads in the vertical direction and the horizontal direction. The heat exchange surface HSa2 is arranged on the right side of the outdoor air conditioner 100 and spreads in the vertical direction and the front-back direction. The heat exchange surface HSa3 is arranged on the front side of the outdoor air conditioner 100 and spreads in the vertical direction and the horizontal direction. The heat exchange surface HSa4 is arranged on the left side of the outdoor air conditioner 100 and spreads in the vertical direction and the front-back direction.

When the user-side fan 50 is operated, the air taken in from the outside of the casing 90 through the through hole (not shown) on the lower side of the second decorative plate 91b by the airflow Fa generated by the user-side fan 50 is taken in. , Passes through the heat exchange surfaces HSa1 to HSa4 of the user side heat exchanger 30. The air that has passed through the heat exchange surfaces HSa1 to HSa4 exchanges heat with the refrigerant flowing inside the refrigerant heat transfer tube 33 of the user side heat exchanger 30. The air that has exchanged heat with the refrigerant in the user-side heat exchanger 30 passes through the bell mouth 54 and the user-side fan 50 arranged above the intermediate plate 98 by the airflow Fa generated by the user-side fan 50. The air that has passed through the user-side fan 50 flows through the air flow path FP that has passed through the user-side heat exchanger 30 formed in the blowout area A21. The air that has passed through the heat exchanger 30 on the utilization side is discharged from the outlets 82a to 82d that form a part of the flow path FP to the through hole (not shown) on the lower side of the second decorative plate 91b and the third decorative plate. It is blown out of the casing 90 through a through hole (not shown) of the plate 91c. In the present embodiment, since the outlets 82a to 82d are provided on the four side surfaces (front surface, rear surface, right surface, and left surface) of the casing 90 having a substantially rectangular parallelepiped shape, the air passing through the user-side heat exchanger 30 is collected. Blow out from the casing 90 in multiple directions (in all directions).

(2-7) Expansion mechanism The expansion mechanism 16 is a mechanism for lowering the pressure of the high-pressure refrigerant in the refrigeration cycle by the throttle expansion action. In this embodiment, the expansion mechanism 16 is an electronic expansion valve. However, the expansion mechanism 16 is not limited to the electronic expansion valve whose opening degree can be adjusted, and may be a mechanical expansion valve used together with the heat-sensitive cylinder. Further, from the viewpoint of reducing the device cost and the like, the expansion mechanism 16 may be a capillary tube whose degree of decompression and flow rate cannot be adjusted.

(2-8) Heat source side fan The heat source side fan 60 is a mechanism for generating an air flow Fb so that air passes through the heat source side heat exchanger 40. The heat source side fan 60 is driven by the motor 62. When the motor 62 is operated and the heat source side fan 60 generates the air flow Fb, air is taken into the casing 90 from the side surface of the casing 90 through the through hole of the first decorative plate 91a. In the present embodiment, when the heat source side fan 60 generates the air flow Fb, air is taken into the casing 90 from above the outlets 82a to 82d through the through hole of the first decorative plate 91a. The air taken into the casing 90 passes through the heat source side heat exchanger 40, then passes through the heat source side fan 60 and the bell mouth 64, and flows out from the exhaust port 84 at the upper part of the casing 90.

The heat source side fan 60 is a propeller fan in this embodiment. However, the type of the heat source side fan 60 is not limited to the propeller fan. If it is possible to generate the above-mentioned air flow, the type of the heat source side fan 60 may be appropriately determined. For example, the heat source side fan 60 may be a turbo fan or a sirocco fan.

Further, in the present embodiment, the heat source side fan 60 is arranged on the downstream side of the heat source side heat exchanger 40 in the direction of the air flow Fb generated by the heat source side fan 60, but the present invention is not limited to this. Depending on the design of the air flow path and the like, the heat source side fan 60 may be arranged on the upstream side of the heat source side heat exchanger 40 in the direction of the air flow Fb generated by the heat source side fan 60.

Further, in the present embodiment, the heat source side fan 60 is arranged in the upper part of the casing 90 (above the heat source side heat exchanger 40), but the arrangement of the heat source side fan 60 depends on the type of the heat source side fan 60 and the like. It may be decided as appropriate.

(2-9) User-side fan The user-side fan 50 is a mechanism for generating an air flow Fa so that air passes through the user-side heat exchanger 30. The user-side fan 50 is driven by the motor 52. When the motor 52 is operated and the user-side fan 50 generates an air flow Fa, air is taken into the casing 90 from the side surface of the casing 90 through the through hole of the second decorative plate 91b. In the present embodiment, when the user-side fan 50 generates the airflow Fa, air is taken into the casing 90 from below the outlets 82a to 82d through the through hole of the second decorative plate 91b. The air taken into the casing 90 passes through the heat exchanger 30 on the user side, then passes through the bell mouth 54 and the fan 50 on the user side, and the air outlets 82a to be provided on the side surface of the casing 90. Pass through 82d. The air that has passed through the outlets 82a to 82d passes through the through hole of the third decorative plate 91c and is blown out to the outside of the casing 90.

The user side fan 50 is a turbo fan in this embodiment. However, the type of the user fan 50 is not limited to the turbo fan. If it is possible to generate the above-mentioned airflow, the type of the user-side fan 50 may be appropriately determined. For example, the user fan 50 may be a propeller fan or a sirocco fan.

Further, in the present embodiment, the user-side fan 50 is arranged on the downstream side of the user-side heat exchanger 30 in the direction of the airflow Fa generated by the user-side fan 50, but the present invention is not limited to this. Depending on the design of the air flow path and the like, the user-side fan 50 may be arranged on the upstream side of the heat source-side heat exchanger 40 in the direction of the air flow Fa generated by the user-side fan 50.

Further, in the present embodiment, the user-side fan 50 is arranged in the blowout area A21 above the user-side heat exchanger 30, but the user-side fan 50 is appropriately arranged according to the type of the user-side fan 50 and the like. It should be decided.

(2-10) Instruction unit The instruction unit 80 transmits an execution instruction instructing the control device 70 to execute the refrigeration cycle operation. The instruction unit 80 receives an execution instruction for either cooling / dehumidifying operation or heating operation, a target temperature, or the like from the user, and transmits these as control signals to the control device 70. The indicator 80 is typically an operation switch (not shown) provided on the casing 90.

(2-11) Control device The control device 70 controls the operation of each part constituting the outdoor air conditioner 100. The control device 70 executes a refrigerating cycle operation in which the refrigerant circuit 20 performs a refrigerating cycle by controlling the operation of each part constituting the outdoor air conditioner 100. The cooling / dehumidifying operation and the heating operation are examples of the refrigerating cycle operation. The control device 70 includes a microcomputer having parts such as a CPU and a memory. The control device 70 is electrically connected to various parts of the outdoor air conditioner 100 including the compressor 10, the switching mechanism 12, the expansion mechanism 16, the user side fan 50, the heat source side fan 60, and the indicator 80. (See the dashed line in FIG. 2). Further, the control device 70 is also electrically connected to a temperature sensor (not shown) provided in each part of the outdoor air conditioner 100. The temperature sensor includes, for example, a temperature sensor for measuring the temperature of the refrigerant in each part of the refrigerant circuit 20, a temperature sensor for measuring the outside air temperature, and the like. Each part of the refrigerant circuit 20 of the outdoor air conditioner 100 may be provided with a pressure sensor for measuring the pressure of the refrigerant. When the outdoor air conditioner 100 is provided with a pressure sensor, the pressure sensor includes, for example, a suction pressure sensor provided in the suction pipe 20a and a discharge pressure sensor provided in the discharge pipe 20b. The control device 70 controls the operation of the outdoor air conditioner 100 by executing a program stored in the memory by the CPU in the microcomputer. The control device 70 is an example of a control unit.

The control device 70 of the present embodiment is only an example of a control device that controls the operation of the outdoor air conditioner 100. The control device may realize the same function as the function exhibited by the control device 70 of the present embodiment by hardware such as a logic circuit, or may be realized by a combination of hardware and software.

Next, the operations of the outdoor air conditioner 100 during the cooling / dehumidifying operation, the heating operation, and the first pre-operation control will be described.

(2-11-1) Upon receiving the cooling / dehumidifying operation execution instruction from the cooling / dehumidifying operation instruction unit 80, the control device 70 executes the first pre-operation control. Although the details will be described later, in the first pre-operation control, the control device 70 controls the switching mechanism 12 so that the operating state of the outdoor air conditioner 100 becomes the first operating state, and sets the first state (FIG. 2). Refer to the solid line in the switching mechanism 12 of. When the first pre-operation control is completed, the control device 70 starts the operation of the compressor 10, the heat source side fan 60, and the user side fan 50, and starts the operation of the compressor 10, the expansion mechanism 16, the heat source side fan 60, and The operation of the user-side fan 50 is appropriately controlled.

As a result of controlling the operation of the outdoor air conditioner 100 in this way, the low-pressure gas refrigerant in the refrigeration cycle in the refrigerant circuit 20 is sucked into the compressor 10 and compressed, and becomes a high-pressure gas refrigerant in the refrigeration cycle. The gas refrigerant compressed by the compressor 10 is sent to the heat source side heat exchanger 40 through the switching mechanism 12. The high-pressure gas refrigerant in the refrigeration cycle sent to the heat source side heat exchanger 40 is cooled by exchanging heat with the outdoor air supplied by the heat source side fan 60 in the heat source side heat exchanger 40 that functions as a condenser. Condenses and becomes a high-pressure liquid refrigerant. On the other hand, the air heated by the heat source side heat exchanger 40 that functions as a condenser is discharged to the outside of the casing 90 from the exhaust port 84 at the upper part of the casing 90. The liquid refrigerant condensed in the heat source side heat exchanger 40 is decompressed by the expansion mechanism 16 to expand, and is sent to the user side heat exchanger 30. The low-pressure gas-liquid two-phase state refrigerant sent to the user-side heat exchanger 30 exchanges heat with the outdoor air supplied by the user-side fan 50 in the user-side heat exchanger 30 that functions as an evaporator. It evaporates and becomes a low-pressure gas refrigerant. The low-pressure gas refrigerant is sent to the compressor 10 through the second gas connecting pipe 20e and the suction pipe 20a, and is sucked into the compressor 10 again. On the other hand, the air cooled by the utilization side heat exchanger 30 that functions as an evaporator is blown out to all sides of the casing 90 through the outlets 82a to 82d on the side surface of the casing 90.

(2-11-2) Upon receiving the heating operation execution instruction from the heating operation instruction unit 80, the control device 70 executes the first pre-operation control. Although the details will be described later, in the first pre-operation control, the control device 70 controls the switching mechanism 12 so that the operating state of the outdoor air conditioner 100 becomes the second operating state (FIG. 2). See the broken line in the switching mechanism 12 of. When the first pre-operation control is completed, the control device 70 starts the operation of the compressor 10, the heat source side fan 60, and the user side fan 50, and starts the operation of the compressor 10, the expansion mechanism 16, the heat source side fan 60, and The operation of the user-side fan 50 is appropriately controlled.

As a result of controlling the operation of the outdoor air conditioner 100 in this way, the gas refrigerant in the low-pressure refrigeration cycle in the refrigerant circuit 20 is sucked into the compressor 10 and compressed, and becomes a high-pressure gas refrigerant in the refrigeration cycle. The gas refrigerant compressed by the compressor 10 is sent to the user side heat exchanger 30 through the switching mechanism 12. The high-pressure gas refrigerant in the refrigeration cycle sent to the user-side heat exchanger 30 is cooled by exchanging heat with the outdoor air supplied by the user-side fan 50 in the user-side heat exchanger 30 that functions as a condenser. Condenses and becomes a high-pressure liquid refrigerant. On the other hand, the air heated by the utilization side heat exchanger 30 that functions as a condenser is blown out to all sides of the casing 90 through the outlets 82a to 82d on the side surface of the casing 90. The liquid refrigerant condensed in the user-side heat exchanger 30 is decompressed by the expansion mechanism 16 to expand, and is sent to the heat source-side heat exchanger 40. The low-pressure gas-liquid two-phase state refrigerant sent to the heat source side heat exchanger 40 exchanges heat with the outdoor air supplied by the heat source side fan 60 in the heat source side heat exchanger 40 that functions as an evaporator. It evaporates and becomes a low-pressure gas refrigerant. The low-pressure gas refrigerant is sent to the compressor 10 through the first gas connecting pipe 20c and the suction pipe 20a, and is sucked into the compressor 10 again. On the other hand, the air cooled by the heat source side heat exchanger 40 that functions as an evaporator is discharged to the outside of the casing 90 from the exhaust port 84 at the upper part of the casing 90.

(2-11-3) First pre-operation control In the first pre-operation control, cooling / dehumidifying operation and heating are performed in order to prevent the amount of compressor oil in the compressor 10 from falling below the required amount due to outdoor use. This is the control executed by the control device 70 before the operation is started. The first pre-operation control is an example of the first control.

In the first pre-operation control, the control device 70 starts the compressor 10 for a predetermined first period, and then stops the compressor 10 for a predetermined second period longer than the first period. The first period is, for example, 1 second or more and 20 seconds or less. The second period is, for example, 1 minute or more and 20 minutes or less.

The control flow of the first pre-operation control will be explained. FIG. 7 is a flowchart showing a control flow of the first pre-operation control executed by the control device 70. When the control device 70 receives the execution instruction of the refrigeration cycle operation from the instruction unit 80, the control device 70 starts the first pre-operation control.

In step S110, the control device 70 activates the compressor 10 and proceeds to step S120.

In step S120, the control device 70 determines whether or not the first period has elapsed from the start of the compressor 10. The control device 70 repeats step S120 until the first period elapses from the start of the compressor 10 (No), and proceeds to step S130 when the first period elapses from the start of the compressor 10 (Yes).

In step S130, the control device 70 stops the compressor 10 and proceeds to step S140.

In step S140, the control device 70 determines whether or not the second period has elapsed since the compressor 10 was stopped. The control device 70 repeats step S140 from the stop of the compressor 10 until the second period elapses (No), and ends the first pre-operation control when the second period elapses from the stop of the compressor 10 (Yes).

When the first pre-operation control is completed, the control device 70 starts the refrigeration cycle operation based on the execution instruction of the refrigeration cycle operation from the instruction unit 80.

(3) Features (3-1)
The outdoor air conditioner 100 of the present embodiment is an air conditioner used outdoors and includes a refrigerant circuit 20 and a control device 70. The refrigerant circuit 20 includes a compressor 10, a heat source side heat exchanger 40, and a user side heat exchanger 30. The refrigerant circuit 20 causes the refrigeration cycle to be performed by circulating the refrigerant through the compressor 10, the heat source side heat exchanger 40, and the user side heat exchanger 30. The control device 70 activates the compressor 10 to execute a refrigerating cycle operation in which the refrigerant circuit 20 performs a refrigerating cycle. The control device 70 executes the first pre-operation control (first control) in which the compressor 10 is started for a predetermined first period and then the compressor 10 is stopped for a predetermined second period longer than the first period. , The refrigeration cycle operation is started after the first pre-operation control is completed.

In the outdoor air conditioner 100, in the first pre-operation control, the compressor 10 is started for the first period and the temperature inside the compressor 10 rises, so that the refrigerant dissolved in the compressor oil is vaporized from the compressor oil. It is separated and discharged from the compressor 10. By setting the first period to a short period of time, the amount of compressor oil discharged from the compressor 10 is limited even if the compressor oil foams due to the refrigerant vaporized inside the compressor 10 at this time. It is a target.

The refrigerant discharged from the compressor 10 is sent to the heat source side heat exchanger 40 and the user side heat exchanger 30, but when the compressor 10 is stopped for the second period, the heat source side heat exchanger 40 is used. The difference between the pressure of the refrigerant and the pressure of the refrigerant in the heat exchanger 30 on the user side becomes small. As a result, the diffusion of the refrigerant dissolved in the compressor oil into the refrigerant circuit 20 is promoted, and the amount of the refrigerant in the compressor 10 is reduced. As a result, even if the refrigeration cycle operation is started after the first pre-operation control, the amount of the compressor oil is suppressed from falling below the required amount due to the discharge of the compressor oil together with the refrigerant.

Further, when the outdoor air conditioner 100 is placed in a place having a relatively low temperature such as outdoors for a long time, the refrigerant in the refrigerant circuit 20 is condensed, and the refrigerant having a high degree of wetness is unevenly present in the refrigerant circuit 20. I have something to do. When the refrigeration cycle operation is started in that state, the highly moist refrigerant returns to the compressor 10 at once, so that the temperature of the compressor 10 drops, and the compressor oil is easily discharged from the compressor 10 together with the refrigerant. However, in the outdoor air conditioner 100, by stopping the compressor 10 for the second period, the refrigerant moves from the high pressure side to the low pressure side, so that the refrigerant can be dispersed and exist in the refrigerant circuit 20. As a result, even if the refrigeration cycle operation is started, the highly moist refrigerant is suppressed from returning to the compressor 10 at once, and the amount of compressor oil is suppressed from falling below the required amount.

As described above, according to the outdoor air conditioner 100, it is possible to prevent the amount of compressor oil from falling below the required amount by a simple control of starting and stopping the compressor 10.

(3-2)
The first period is 1 second or more and 20 seconds or less.

By setting the first period to the above period, the amount of compressor oil discharged from the compressor 10 can be suppressed even if forming occurs.

(3-3)
The second period is 1 minute or more and 20 minutes or less.

By setting the second period to the above period, the diffusion of the refrigerant dissolved in the compressor oil into the refrigerant circuit 20 is promoted, and the amount of the refrigerant in the compressor 10 can be reduced.

(3-4)
The compressor 10 of the outdoor air conditioner 100 is a compressor (non-inverter compressor) having a constant refrigerant discharge capacity per unit time.

A non-inverter compressor with a constant refrigerant discharge capacity per unit time can be manufactured at low cost, but the discharge capacity cannot be finely controlled. Therefore, in an outdoor air conditioner having a non-inverter compressor, the compressor reaches the maximum rotation speed at the time of starting, intense forming occurs in the compressor, and the amount of compressor oil tends to be less than the required amount. According to the outdoor air conditioner 100, even when a non-inverter compressor is used for the compressor 10, the amount of compressor oil is required in the compressor 10 by simple control of starting and stopping the compressor 10. It is possible to suppress the amount from falling below the amount. Therefore, the manufacturing cost can be kept low.

(3-5)
The heat source side heat exchanger 40 and the user side heat exchanger 30 of the outdoor air conditioner 100 are arranged above the compressor 10.

In the outdoor air conditioner 100 in which the heat source side heat exchanger 40 and the user side heat exchanger 30 are arranged above the compressor 10, the heat source side heat exchanger 40 and the user side heat exchanger 30 are included. A large amount of the refrigerant condensed in (1) tends to flow into the compressor 10. In particular, in the case of an integrated air conditioner in which the user-side heat exchanger 30 and the heat source-side heat exchanger 40 are housed in one casing 90, such as the outdoor air conditioner 100, these are placed in different casings. This tendency is due to the fact that the suction pipe 20a and the second gas connecting pipe 20e provided between the user side heat exchanger 30 and the compressor 10 tend to be shorter than the housed separate type air conditioner. Is remarkable.

Therefore, the amount of compressor oil for outdoor use of the heat source side heat exchanger 40 and the user side heat exchanger 30 is less than the required amount as compared with the outdoor air conditioner arranged below the compressor 10. Cheap.

In the outdoor air conditioner 100, even when the heat source side heat exchanger 40 and the user side heat exchanger 30 are arranged above the compressor 10, the amount of compressor oil in the compressor 10 is less than the required amount. Can be suppressed by simple control. Therefore, there is a high degree of freedom in design regarding the arrangement of the heat source side heat exchanger 40, the user side heat exchanger 30, and the compressor 10.

(4) Modification example The following is a modification of the above embodiment. It should be noted that the partial configuration or the entire configuration of each modification shown here may be applied in combination with other modifications to the extent that there is no contradiction.

(4-1) Modification 1A
The control device 70 may switch the switching mechanism 12 to a predetermined state based on the execution instruction of the refrigeration cycle operation from the instruction unit 80 during the first pre-operation control.

FIG. 8 is a flowchart showing a control flow of the first pre-operation control executed by the control device 70 in the outdoor air conditioner 100 according to the modified example 1A. In the control flow shown in FIG. 8, the control device 70 switches the switching mechanism 12 based on the execution instruction of the refrigeration cycle operation from the instruction unit 80 in the step S105 before the step S110.

Specifically, when the execution instruction is the execution instruction of the cooling / dehumidifying operation (when the switching mechanism 12 is set to the first state in the refrigeration cycle operation), the control device 70 switches the switching mechanism 12 to the second state. .. Further, when the execution instruction is the execution instruction of the heating operation (when the switching mechanism 12 is set to the second state in the refrigeration cycle operation), the control device 70 switches the switching mechanism 12 to the first state.

After that, the control device 70 executes step S140 from step S110 described above to end the first pre-operation control.

When the first pre-operation control is completed, the control device 70 starts the refrigeration cycle operation based on the execution instruction of the refrigeration cycle operation from the instruction unit 80. At the start of the refrigeration cycle operation, the switching mechanism 12 switched in step S105 is switched again by the control device 70 so as to be in a state based on the execution instruction of the refrigeration cycle operation from the instruction unit 80.

As a result, in the outdoor air conditioner 100 according to the modified example 1A, the refrigerant separated in the compressor 10 in the first pre-operation control is directed toward the heat exchanger on the low pressure side in the subsequent refrigeration cycle operation. It is discharged. Therefore, even if the refrigerant discharged from the compressor 10 contains the compressor oil, the compressor oil contained in the refrigerant can be quickly returned to the compressor after the start of the refrigeration cycle operation, so that the amount of the compressor oil can be reduced. Can be effectively suppressed from falling below the required amount.

Further, in the outdoor air conditioner 100, since the heat source side heat exchanger 40 is arranged above the user side heat exchanger 30, the heat source side heat exchanger 40 condenses while the outdoor air conditioner 100 is stopped. A part of the refrigerant also collects in the heat exchanger 30 on the user side. Even if a part of the condensed refrigerant is accumulated in the heat exchanger 30 on the user side, the outdoor air conditioner 100 compresses the refrigerant in the first pre-operation control by executing the cooling / dehumidifying operation. By discharging the refrigerant separated in the machine 10 to the user side heat exchanger 30, the refrigerant accumulated in the user side heat exchanger 30 can be evaporated and sent to the heat source side heat exchanger 40.

(4-2) Modification 1B
In the control flow shown in FIG. 8, the control device 70 may switch the switching mechanism 12 after the compressor 10 is stopped and before the first pre-operation control is completed.

FIG. 9 is a flowchart showing a control flow of the first pre-operation control executed by the control device 70 in the outdoor air conditioner 100 according to the modified example 1B. In the control flow shown in FIG. 9, the control device 70 switches the switching mechanism 12 in step S135 after step S130.

In other words, in the first pre-operation control, the control device 70 sets the switching mechanism 12 in the first state while the compressor 10 is running, and sets the switching mechanism 12 in the second state in the refrigeration cycle operation. Alternatively, in the first control, the control device 70 sets the switching mechanism 12 in two states while the compressor 10 is running, and sets the switching mechanism 12 in the first state in the refrigeration cycle operation.

(4-3) Modification 1C
In the second period, the control device 70 may make the opening degree of the expansion mechanism 16 larger than the opening degree during the refrigerating cycle operation.

As a result, the difference between the pressure in the heat source side heat exchanger 40 and the pressure in the user side heat exchanger 30 tends to be small, so that the diffusion of the refrigerant into the refrigerant circuit 20 is promoted and the compressor 10 is compressed. It is effectively suppressed that the amount of machine oil falls below the required amount.

<Second Embodiment>
The outdoor air conditioner 101 according to the second embodiment will be described below with reference to the drawings, focusing on the differences from the outdoor air conditioner 100.

(1) Overall Overview FIG. 10 is a diagram schematically showing a refrigerant circuit 20 of an outdoor air conditioner 101. The difference between the outdoor air conditioner 101 and the outdoor air conditioner 100 is that the outdoor air conditioner 101 further includes a crankcase heater 13 and also includes a control device 71 instead of the control device 70.

(2) Detailed Description (2-1) Crankcase Heater The crankcase heater 13 heats the compressor oil stored in the compressor 10. In the present embodiment, the crankcase heater 13 is attached to the bottom wall surface of the compressor 10. The crankcase heater 13 is controlled by the control device 71 and generates heat when energized.

(2-2) Control device The control device 71 controls the operation of each part constituting the outdoor air conditioner 101. The difference between the control device 71 and the control device 70 is that the control device 71 is electrically connected to the crankcase heater 13, and the control device 71 executes the second pre-operation control including the preheating control. It is a point to do. The preheating control is a control in which the control device 71 heats the crankcase heater 13. Preheating control is an example of the second control.

Next, the operation of the outdoor air conditioner 101 during the second pre-operation control will be described.

(2-2-1) Second Pre-Operation Control The control device 71 executes the second pre-operation control when it receives an execution instruction for cooling / dehumidifying operation or heating operation from the instruction unit 80. The difference between the second pre-operation control executed by the control device 71 and the first pre-operation control executed by the control device 70 is that in the second pre-operation control, the first preheating control is started after the control device 71 starts the preheating control. This is the point of executing pre-operation control. Preheating control continues until the refrigeration cycle operation is started. In other words, the preheating control is continued until the second pre-operation control is completed.

The control flow of the second pre-operation control executed by the control device 71 will be described. FIG. 11 is a flowchart showing a control flow of the second pre-operation control executed by the control device 71. When the control device 71 receives the execution instruction of the refrigeration cycle operation from the instruction unit 80, the control device 71 starts the second pre-operation control.

In step S21, the control device 71 starts preheating control, heats the crankcase heater 13, and proceeds to step S22.

In step S22, the control device 71 executes the first pre-operation control steps S11 to S16 shown in FIG. 7. The description of the first pre-operation control will be omitted. The control device 71 proceeds to step S23 when step S22 is completed.

In step S23, the control device 71 ends the preheating control, stops the heat generation of the crankcase heater 13, and ends the second pre-operation control.

When the second pre-operation control is completed, the control device 71 starts the refrigeration cycle operation based on the execution instruction of the refrigeration cycle operation from the instruction unit 80.

(3) Features (3-1)
The outdoor air conditioner 101 of the present embodiment further includes a crankcase heater 13 that heats the compressor oil of the compressor 10 by generating heat. The control device 71 executes the first pre-operation control after starting the preheating control (second control) for heating the crankcase heater 13.

In the outdoor air conditioner 101, the heat generated by the crankcase heater 13 heats the refrigerant dissolved in the compressor oil, so that the amount of the refrigerant dissolved in the compressor oil can be further reduced. Therefore, according to the outdoor air conditioner 101, it is possible to more effectively prevent the amount of compressor oil from falling below the required amount.

(4) Modification example (4-1) Modification example 2A
The control device 71 may execute the preheating control after the power is turned on to the outdoor air conditioner 101 without waiting for the execution instruction of the refrigeration cycle operation from the instruction unit 80. In this case, if the control device 71 is heated to a period during which it is possible to prevent the compressor oil from falling below the required amount when the execution instruction is received, it is not necessary to execute the first pre-operation control. Hereinafter, the third pre-operation control executed by the control device 71 of the outdoor air conditioner 101 according to the modified example 2A will be described.

(4-1-1) Third Pre-Operation Control In the outdoor air conditioner 101 according to the modified example 2A, the control device 71 starts preheating control when the power is turned on to the outdoor air conditioner 101. When the control device 71 receives the execution instruction from the instruction unit 80, the control device 71 compares the elapsed time from the start of heat generation of the crankcase heater 13 with the predetermined third period. Then, if the elapsed time from the start of heat generation of the crankcase heater 13 is the third period or more, the control device 71 starts the refrigeration cycle operation without executing the first pre-operation control. Further, if the elapsed time from the start of heat generation of the crankcase heater 13 is less than the third period, the control device 71 executes the first pre-operation control, and after the first pre-operation control is completed, the refrigeration cycle Start operation.

The outdoor air conditioner 101 according to the modification 2A further includes a timer (not shown). The timer measures the elapsed time since the crankcase heater 13 starts to generate heat.

The control flow of the third pre-operation control executed by the control device 71 of the outdoor air conditioner 101 according to the modification 2A will be described. FIG. 12 is a flowchart showing a control flow of the third pre-operation control executed by the control device 71.

The control device 71 starts control when the power is turned on to the outdoor air conditioner 102.

In step S31, the control device 71 starts preheating control, heats the crankcase heater 13, and proceeds to step S32. At this time, the timer starts measuring the elapsed time.

In step S32, the control device 71 determines whether or not the refrigerating cycle operation execution instruction has been received from the instruction unit 80. The control device 71 repeats step S32 until the execution instruction is received (No), and when the execution instruction is received (Yes), the control device 71 proceeds to step S33.

In step S33, the control device 71 acquires the elapsed time from the start of heat generation of the crankcase heater 13 from the timer, and proceeds to step S34.

In step S34, the control device 71 determines whether or not the acquired elapsed time is equal to or longer than the predetermined third period. If the elapsed time is the third period or more (Yes), the control device 71 ends the third pre-operation control, and if the elapsed time is less than the third period, proceeds to step S35 (No).

In step S35, the control device 71 executes steps S11 to S16 of the first pre-operation control. The control device 71 ends the third pre-operation control when the steps S11 to S16 of the first pre-operation control are completed.

When the third pre-operation control is completed, the control device 71 starts the refrigeration cycle operation based on the execution instruction of the refrigeration cycle operation from the instruction unit 80.

The third period is a period in which it is possible to separate the refrigerant dissolved in the compressor oil only by the heat generated by the crankcase heater 13 and prevent the amount of the compressor oil from falling below the required amount. The third period is, for example, 90 minutes.

In the third pre-operation control, when the control device 71 is heated to a period during which the crankcase heater 13 can prevent the compressor oil from falling below the required amount by the time the control device 71 receives the execution instruction, the first pre-operation control is performed. Start refrigeration cycle operation without execution. If the compressor oil is not sufficiently heated by the crankcase heater 13 by the time the control device 71 receives the execution instruction, the refrigeration cycle operation is started after the first pre-operation control is executed.

Therefore, the time from receiving the execution instruction from the instruction unit 80 to starting the refrigeration cycle operation can be shortened, and the convenience is improved.

The first pre-operation control was evaluated using the above-mentioned outdoor air conditioner 100. FIG. 13 is a graph showing the movement of the compressor and the oil level behavior of the compressor oil in the embodiment.

In the embodiment, the first pre-operation control was performed before the start of the cooling operation. The first period was 5 seconds and the second period was 3 minutes. The oil level behavior was observed with a sight glass provided in the compressor. In FIG. 13, the timing at which the control device 70 starts the first pre-operation control is shown as 0 minute.

As shown in FIG. 13, although the oil level in the compressor once dropped once the cooling operation started, it did not fall below the height of the lower end of the oil pickup shown by the dotted line in the graph. In addition, the oil level that hit the bottom about 2 minutes after the start of the cooling operation rose immediately after that. The oil pickup is a pipe for sucking oil from the compressor, one end of which is connected to the fuel filler port and the other end of which is arranged in the oil reservoir space in the compressor.

From the above results, it was confirmed that the amount of compressor oil could be suppressed from falling below the required amount by executing the first pre-operation control.

Although the embodiments of the present disclosure have been described above, it is understood that the purpose of the present disclosure described in the claims and various changes in the form and details are possible without departing from the scope. Let's do it.

10 Compressor 12 Switching mechanism 13 Crankcase heater 20 Refrigerant circuit 30 User side heat exchanger 36 Drain pan 40 Heat source side heat exchanger 46 Drain pan 50 User side fan (first fan)
60 Heat source side fan (second fan)
70, 71 Control device 80 Indicator 82 (82a, 82b, 82c, 82d) Outlet 90

Casing

100, 101 Outdoor air conditioner FP flow path

Japanese Patent Application No. 2020-003182

Claims

An air conditioner (100) used outdoors,
It has a compressor (10), a heat source side heat exchanger (40), and a user side heat exchanger (30), and uses the compressor, the heat source side heat exchanger, and the user side heat exchanger as a refrigerant. Refrigerant circuit (20) that causes the refrigeration cycle to be performed by circulating
A control unit (70) that activates the compressor and executes a refrigerating cycle operation for causing the refrigerant circuit to perform the refrigerating cycle.
Equipped with
The control unit
After starting the compressor for a predetermined first period, the first control for stopping the compressor for a predetermined second period longer than the first period is executed.
After the first control is completed, the refrigeration cycle operation is started.
Outdoor air conditioner.
The first period is
1 second or more and 20 seconds or less,
The outdoor air conditioner according to claim 1.
The second period is
1 minute or more and 20 minutes or less,
The outdoor air conditioner according to claim 1 or 2.
The refrigerant circuit is
The first state in which the refrigerant is circulated in the order of the compressor, the heat source side heat exchanger, and the user side heat exchanger, and the refrigerant is transferred to the compressor, the user side heat exchanger, and the heat source side heat. It has a switching mechanism (12) that switches between the second state that circulates in the order of the exchanger and the second state.
The control unit
In the first control, the switching mechanism is set to the first state while the compressor is being activated, and in the refrigeration cycle operation, the switching mechanism is set to the second state, or
In the first control, the switching mechanism is set to the second state while the compressor is being activated, and in the refrigeration cycle operation, the switching mechanism is set to the first state.
The outdoor air conditioner according to any one of claims 1 to 3.
The control unit
In the first control, the switching mechanism is set to the first state, and in the refrigerating cycle operation, the switching mechanism is set to the second state, or
In the first control, the switching mechanism is set to the second state, and in the refrigerating cycle operation, the switching mechanism is set to the first state.
The outdoor air conditioner according to claim 4.
The compressor
The discharge capacity of the refrigerant per unit time is constant.
The outdoor air conditioner according to any one of claims 1 to 5.
The heat source side heat exchanger is
Located above the user heat exchanger,
The outdoor air conditioner according to any one of claims 1 to 6.
The heat source side heat exchanger and the user side heat exchanger are
Located above the compressor,
The outdoor air conditioner according to any one of claims 1 to 7.
A crankcase heater (13) that heats the compressor oil of the compressor by generating heat is further provided.
The control unit
The first control is executed after the second control for heating the crankcase heater is started.
The outdoor air conditioner according to any one of claims 1 to 8.
The control unit
The second control is continued until the refrigeration cycle operation is started.
The outdoor air conditioner according to claim 9.
A timer that measures the elapsed time since the crankcase heater started to generate heat,
An instruction unit (80) for transmitting an execution instruction instructing the control unit to execute the refrigeration cycle operation, and an instruction unit (80).
Further prepare
The control unit
When the power is turned on, the second control is started.
When the execution instruction is received from the instruction unit,
If the elapsed time is equal to or longer than the predetermined third period, the refrigeration cycle operation is started without executing the first control.
If the elapsed time is less than the third period, the first control is executed, and the refrigeration cycle operation is started after the first control is completed.
The outdoor air conditioner according to claim 9 or 10.