JP2011127807A - Outdoor unit, air conditioner and method of operating the air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an outdoor unit capable of efficiently suppressing temperature increase of a control substrate even when the outdoor unit includes a fan stopped during partial load operation. <P>SOLUTION: A fan 6a is provided on the upper side of a heat source side heat exchanger 1a in which a refrigerant is made to flow during both the partial load operation and maximum load operation. A heat sink 5 is arranged below an end of a blade of the fan 6a. The fan 6b is provided on the upper side of a heat source side heat exchanger 1b in which a refrigerant is made to flow during the maximum load operation and is not made to flow during the partial load operation, and is stopped or reversely rotated during the partial load operation. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an air conditioner including an outdoor unit having a heat sink for cooling a control device, and a method for operating the air conditioner.

  The air conditioner configures a refrigerant circuit by connecting an outdoor unit including a compressor, a heat exchanger, and the like and an indoor unit including a use-side heat exchanger that cools and heats the room with a refrigerant pipe. In the air conditioner, it is necessary to adjust the amount of heat exchanged with ambient air in the heat exchanger in accordance with the indoor set temperature and the air volume setting set in the operation unit. The amount of heat exchanged is adjusted by the capacity of the compressor and the rotational speed of the blower provided near the heat exchanger. In recent years, the capacity and rotation of the compressor and blower are driven by an inverter circuit provided in the control device. Often adjust the number. In that case, heat loss occurs in the inverter circuit of the control device and heat is generated. Therefore, a heat sink is attached to cool the control device. The heat dissipation of the heat sink is determined by the temperature difference between the ambient temperature and the heat sink and the wind speed.

  As a conventional outdoor unit, two blowers are provided side by side on the top of the housing, a heat exchanger is provided in the housing across the other side wall facing the side wall, and a control device including a heat sink is installed in the housing. The outdoor unit provided in a part of the inner wall of the is described. (See Patent Document 1)

JP 2006-138573 A (columns 0012 to 0015, FIG. 1)

  In the conventional outdoor unit, when the two fans are driven independently during partial load operation, depending on where the heat sink is installed, the wind of the fan cannot be used effectively and the temperature of the control device rises excessively. there were.

  The present invention provides an outdoor unit and an air conditioner that can prevent a temperature rise of a control device by disposing a heat sink at a position where the wind of the blower always hits even if a plurality of blowers are independently driven during partial load operation. For the purpose.

  It is another object of the present invention to provide an operation method of an air conditioner that can efficiently blow air to a heat sink during partial load operation to prevent a temperature rise of a control device.

  In order to solve the above problems, an outdoor unit of the present invention includes a housing having an opening on a side surface, a compressor installed inside the housing, a control device that has an inverter circuit and controls the compressor. A first heat exchanger through which refrigerant flows during partial load operation with a compressor operating capacity equal to or less than a predetermined value, a second heat exchanger through which refrigerant does not flow during partial load operation, and an upper portion of the first heat exchanger A first blower that blows air to the first heat exchanger during partial load operation, a second blower that is provided above the second heat exchanger and stops during partial load operation, A heat sink that cools the control device provided below the end of the blade of the blower and above the housing is provided.

  In addition, a housing having an opening on the side surface, a compressor installed inside the housing, a control device that has an inverter circuit to control the compressor, and a partial load in which the operating capacity of the compressor is a predetermined value or less A first heat exchanger through which refrigerant flows during operation, a second heat exchanger in which refrigerant does not flow during partial load operation, and a first heat exchanger provided above the first heat exchanger and rotating forward from below during partial load operation A first blower that blows upward, a second blower that is provided above the second heat exchanger and blows from top to bottom in reverse rotation during partial load operation, and an end of a blade of the first blower And a heat sink for cooling the control device provided at the upper part of the housing.

  In addition, a housing having an opening on the side surface, a compressor installed inside the housing, a control device that has an inverter circuit to control the compressor, and a partial load in which the operating capacity of the compressor is a predetermined value or less A first heat exchanger through which a high-temperature and high-pressure refrigerant compressed by a compressor during operation flows, a decompression means for depressurizing a refrigerant that has been subjected to heat exchange by the first heat exchanger during partial load operation and has become a low-temperature and high-pressure, and a part A second heat exchanger through which the refrigerant that has passed through the decompression means during load operation and has become low-temperature and low-pressure flows, and is provided above the first heat exchanger and blows air to the first heat exchanger during partial load operation. A first blower, a second blower that is provided above the second heat exchanger and blows air to the second heat exchanger during partial load operation, and below the end of the rotating blade of the first blower A heat sink for cooling the control device provided at the top of the housing. It is characterized in.

  The operation method of the air conditioner of the present invention includes a housing having an opening on a side surface, a compressor installed inside the housing, and a first heat exchanger provided above the first heat exchanger. A first blower that blows air, a second blower that is provided above the second heat exchanger and blows air to the second heat exchanger, and below the wing end of the first blower. A heat sink that cools the control device provided in the upper part of the housing, an on-off valve that opens and closes the flow path of the refrigerant flowing through the second heat exchanger, a four-way valve that switches between cooling operation and heating operation, a compressor, In a method for operating an air conditioner, comprising: a control device that controls a first blower, a second blower, an on-off valve, and a four-way valve; The apparatus opens the on-off valve, causes the refrigerant to flow through the first heat source side heat exchanger and the second heat source side heat exchanger, The maximum load operation step of driving the blower and the second blower, and the control device closes the on-off valve to flow the refrigerant through the first heat source side heat exchanger to drive the second and first blowers to And a partial load operation step of stopping or reversely rotating the blower.

  It also has a housing having an opening on the side surface, a compressor installed inside the housing and discharging high-temperature and high-pressure refrigerant, a four-way valve connected to the compressor to switch between cooling operation and heating operation, and an inverter circuit. A control device that controls the compressor, a first blower that is provided above the first heat exchanger and blows air to the first heat exchanger, and is provided above the second heat exchanger. A second fan that blows air to the second heat exchanger, a heat sink that cools the control device provided on the upper part of the housing, below the end of the rotating blade of the first fan, and a partial load A branch pipe in which heat is exchanged in the first heat exchanger during operation and the low-temperature high-pressure refrigerant flows to the second heat exchanger, a decompression means provided in the branch pipe for decompressing the low-temperature high-pressure refrigerant, and a second heat exchange An open / close valve that opens and closes the refrigerant flow path, the compressor, the first blower, and the second feed In the operation method of an air conditioner comprising: a control device that controls a machine, an on-off valve, and a four-way valve; and a use side heat exchanger that is connected to the four-way valve to cool and heat the room, the control device opens the on-off valve A maximum load operation process in which the refrigerant flows through the first heat source side heat exchanger and the second heat source side heat exchanger to drive the first blower and the second blower, and the controller controls the on-off valve to control the temperature. A partial load operation step of flowing a low-pressure refrigerant through the first heat exchanger and driving the first blower and the second blower is provided.

  In the outdoor unit and the air conditioner of the present invention, since the heat sink is arranged below the fan that is driven during both the maximum load operation and the partial load operation, the temperature rise of the control board is prevented. There is an effect that can.

  Further, the operation method of the air conditioner according to the present invention drives the blower disposed above the heat sink during both the maximum load operation and the partial load operation, thereby preventing the temperature rise of the control board. There is an effect that can be done.

It is a front view of the outdoor unit of Embodiment 1 of the present invention. It is a top view of the outdoor unit according to Embodiment 1 of the present invention. It is a side view of the outdoor unit of Embodiment 1 of the present invention. It is sectional drawing of the control box and heat sink of Embodiment 1 of this invention. It is a relationship figure of the position of the fan and air volume of Embodiment 1 of this invention. It is a refrigerant | coolant piping figure of the air conditioning apparatus of Embodiment 1 of this invention. It is a front view of the outdoor unit of Embodiment 2 of the present invention. It is a top view of the outdoor unit according to Embodiment 2 of the present invention. It is a flowchart of the operating method of the air conditioning apparatus of Embodiment 1, 2 of this invention. It is a refrigerant | coolant piping figure which shows the flow of the refrigerant | coolant at the time of the air conditioning operation | movement of the air conditioning apparatus of Embodiment 3 of this invention. It is a refrigerant | coolant piping figure at the time of the air_conditionaing | cooling operation of the air conditioning apparatus of Embodiment 3 of this invention. It is a flowchart of the operating method of the air conditioning apparatus of Embodiment 3 of this invention.

Embodiment 1 FIG.
Based on FIG. 1 thru | or FIG. 3, the structure of the outdoor unit 10 concerning this invention is demonstrated. FIG. 1 is a front view of the outdoor unit 10 according to the first embodiment, FIG. 2 is a top view of the outdoor unit, and FIG. 3 is a side view of the outdoor unit 10. 1 is a front view of a state in which the front panel is removed and the inside of the outdoor unit 10 can be seen from the front, and FIG. 2 is a top view of a state in which the top plate is removed and the inside of the outdoor unit 10 can be seen from above. The arrow in the figure represents the wind direction. The outdoor unit 10 has a substantially rectangular parallelepiped shape, and is a bottom plate 12a having a substantially rectangular shape at the bottom, and the heat source side heat exchangers 1a and 1b, the compressor 2 and the like are placed on the bottom plate 12a. Four pillars 11a are provided at the four corners of the bottom plate 12a, and a pillar 11b is provided at the center of the front surface of the outdoor unit 10, and supports the top board 12b installed on the four pillars 11a and 11b. Yes. Fan guards 7a and 7b are provided on the top plate 12b, and the fans 6a and 6b are arranged inside the fan guards 7a and 7b. The fan guards 7a and 7b have openings at the top and bottom and can be ventilated. The fans 6a and 6b blow wind from the bottom to the top during forward rotation, and blow wind from the top to bottom during reverse rotation. The side surface of the outdoor unit 10 includes a front surface, a left side surface, a right side surface, and a back surface, and a front panel 13 is provided on the front surface. No panels are provided on the left side surface 14a, the right side surface 14b, and the back surface 15 so that ventilation is possible. When the fans 6a and 6b rotate forward, wind is sucked from the left side surface 14a, the right side surface 14b, and the back surface 15. The sucked wind passes through the heat source side heat exchangers 1a and 1b and is blown above the fans 6a and 6b. In the first embodiment, no panel is provided on the side surface other than the front surface, but a panel or the like having an opening such as a fence or a slit may be provided.

  A heat source side heat exchanger 1a is installed below the fan 6a, and a heat source side heat exchanger 1b is installed below the fan 6b. The heat source side heat exchangers 1a and 1b have a substantially U-shaped horizontal cross section, and two of the heat source side heat exchangers 1a and 1b are arranged side by side facing forward. In FIG. 1, the heat source side heat exchanger 1a is arranged on the left side in the drawing, and the heat source side heat exchanger 1b is arranged on the right side. The compressor 2 is disposed on the bottom plate 12b on the right side of the outdoor unit 10 and in the U-shaped inner space of the heat source side heat exchanger 1b, and a four-way valve 21 is connected to the compressor 2. . During the cooling operation, the high-temperature and high-pressure refrigerant discharged from the compressor 2 flows from the four-way valve 21 to the heat source side heat exchangers 1a and 1b, and during the heating operation, the refrigerant exchanges indoor use-side heat via the four-way valve 21. It flows to the vessel. A header 3 connected to the four-way valve 21 is provided between the heat source side heat exchanger 1a and the heat source side heat exchanger 1b, and the refrigerant is transferred to the header 3 of the heat source side heat exchanger 1a and the heat source side heat exchanger 1b. The refrigerant flowing through the heat source side heat exchangers 1a and 1b flows from the header 3 to the indoor use side heat exchanger during the heating operation, and from the header 3 to the compressor 2 via the four-way valve 21 during the cooling operation. Flowing.

  The substantially rectangular parallelepiped control box 4 is sandwiched between the front right column 11a and the front center column 11b at a position in front of the heat source side heat exchanger 1a and close to the inner wall surface of the front panel 13, or the front right column 11a. It is installed on a plate sandwiched between pillars 11b at the front center. Inside the control box 4 is provided a control board including an inverter circuit that is driven by supplying AC power of variable frequency to the compressor 2 and the fans 6a and 6b. A heat sink 5 that dissipates heat generated by the inverter circuit is attached to the surface of the control box 4 that faces the heat source side heat exchanger 1a, and the end of the rotating blade of the fan 6a is disposed above the heat sink 5 Pass through. When the blade of the fan 6a is closest to the control box 4, the heat sink 5 is located near the lower end of the blade 6a.

  4 shows a cross-sectional view of the control box 4 of FIG. The control box 4 is a substantially rectangular parallelepiped, and a control board 4b and an inverter circuit 4c are partly installed in a space inside the housing 4a in which a heat sink installation hole and a wiring outlet are opened. The inverter circuit 4c is in contact with the base 5a of the heat sink 5, and the heat of the inverter circuit 4c is transmitted to the base 5a. A plurality of heat radiation fins 5b are integrally formed in parallel with the base 5a, and heat transmitted to the base 5a is radiated by the heat radiation fins 5b. The housing 4a is configured such that the front surface 4d facing the front panel 13 can be opened and closed. When the front panel 13 is removed and the front surface 4d is opened, maintenance of the control board 4b can be performed.

  The control board 4b controls the switching of the four-way valve 21, the rotation speed of the fans 6a and 6b, the opening degree of the decompression means described below, and the opening and closing of the on-off valve. Furthermore, the control board 4b controls the rotation speed of the compressor 2 from the voltage applied to the compressor 2 from the inverter circuit, its frequency, and the duty ratio, and changes the flow rate of refrigerant discharged from the compressor 2 and its pressure.

  FIG. 5 illustrates the relationship between the fan position and the wind speed. The length of the arrow in the figure represents the wind speed, and the longer the arrow, the greater the wind speed. As shown in the figure, the wind speed increases toward the end of the fan blade. The closer to the fan, the higher the wind speed. That is, since the wind speed is the highest directly below the blade tip, the position where the heat sink 5 is disposed is between the bottom plate 12a and the top plate 12b and within a height within 1/2 of the top plate 12b as shown in FIG. In addition, it is desirable that the distance between the rotation axis of the fan 6a and the tip of the blade is within 1/3 of the end of the blade and directly below the blade of the fan 6a. By disposing the heat sink 5 at the position as described above, the heat sink 5 can be cooled by effectively using the air blown from the fan 6a.

When the refrigerant is a hydrofluorocarbon (HFC) type refrigerant, for example, R410a refrigerant, the temperature of the refrigerant discharged from the compressor 2 is determined in advance so as to be 60.5 ° C. (pressure 38 kg / cm ² ). Yes. Since the heat resistance temperature of the control board 4b is 75 ° C. or higher and the maximum temperature of the refrigerant is set lower than the heat resistance temperature of the control board 4b, the high temperature refrigerant discharged from the compressor 2 during the cooling operation is used as heat source side heat. Even if it flows through the exchangers 1a and 1b or the wind that has passed through the heat source side heat exchanger 1a from the outside, the control board 4b can be cooled to a heat resistant temperature or lower. Further, a temperature and pressure detection sensor for detecting the temperature and pressure of the refrigerant discharged from the compressor 2 are installed in the vicinity of the refrigerant discharge port of the compressor 2, and the detected value is output to the control board 4b. If the temperature and pressure of the refrigerant are equal to or higher than a predetermined maximum value, the control board 4b determines that the control board 4b is abnormal and stops the compressor 2. Note that the maximum temperature and pressure of the refrigerant set according to the type of refrigerant to be used are changed.

  FIG. 6 shows a refrigerant circuit diagram of the air-conditioning apparatus according to Embodiment 1. The solid line arrows in the figure indicate the flow of the refrigerant during the heating operation, and the broken line arrows in the figure indicate the flow of the refrigerant during the cooling operation. FIG. 6 shows the flow of the refrigerant during the maximum load operation in which the refrigerant flows through both the heat source side heat exchangers 1a and 1b. The case where the operating capacity of the compressor 2 is equal to or greater than a predetermined value is referred to as maximum load operation, and the case where the operating capacity is equal to or less than the predetermined value is referred to as partial load operation.

  The operating capacity of the compressor 2 can be determined from the frequency of the voltage applied to the compressor 2 by the inverter circuit 4 c incorporated in the control device 10 based on the following “Equation 1”. The operating capacity is obtained using the frequency of the voltage applied to the compressor 2 during the rated capacity operation at which the predetermined maximum work of the compressor 2 is operated as the denominator and the frequency of the voltage applied to the compressor 2 during the operation as the numerator. When the operating capacity is equal to or less than a predetermined value, the partial load operation is set. In addition to the frequency, the maximum load operation time can be similarly obtained from the duty ratio of the inverter circuit as a denominator. If the operating capacity is not proportional to the frequency of the applied voltage applied to the compressor 2, the right side of “Equation 1” may be determined by multiplying the frequency obtained in advance and a function for correcting the operating capacity deviation.

  The partial load operation can also be determined from the amount of refrigerant discharged from the compressor 2, and a flow rate sensor is provided at the discharge port of the compressor 2 so that the compressor 2 in operation can be You may judge from the value which divided the refrigerant | coolant amount discharged by the refrigerant | coolant amount which the compressor 2 discharges at the time of a maximum load driving | operation. It can also be determined from the pressure value of the refrigerant pressure discharged from the compressor 2. If the operating capacity is not proportional to the frequency of the applied voltage applied to the compressor 2, the right side of “Equation 1” may be determined by multiplying the frequency obtained in advance with a function for correcting the deviation of the operating capacity.

  The partial load operation may be determined from the pressure values of the low-pressure refrigerant before flowing into the compressor 2 and the high-pressure refrigerant after discharge, or the rotational speeds of the fans 6a and 6b. During the cooling operation, for example, when the outdoor temperature is low or when the user increases the indoor set temperature, the pressure of the high-pressure refrigerant decreases, so that the control board 4b maintains the pressure value of the high-pressure refrigerant constant. In order to reduce the heat exchange amount of the heat source side heat exchangers 1a and 1b, control is performed to reduce the rotational speed of the fans 6a and 6b. The control board 4b determines that the partial load operation is performed when the pressure value of the high-pressure refrigerant is equal to or lower than a predetermined value or the rotational speed of the fans 6a and 6b is equal to or lower than a predetermined minimum rotational speed. During the heating operation, if the outdoor temperature is high or the user lowers the indoor set temperature, the pressure value of the low-pressure refrigerant increases, so that the heat exchange amount of the heat source side heat exchangers 1a and 1b is decreased. Control is performed to reduce the rotational speed of the fans 6a, 6b. When the pressure value of the low-pressure refrigerant is equal to or higher than the predetermined value or the rotation speed of the fans 6a and 6b is equal to or lower than the predetermined minimum rotation speed, the control board 4b determines that the partial load operation is being performed. In addition, pressure detection sensors are installed at the refrigerant inlet and the refrigerant outlet of the compressor 2 to detect the refrigerant pressure, and the rotational speeds of the fans 6a and 6b are determined from the frequency of the alternating current supplied by the inverter circuit 4c and the power value thereof. The control board 4b calculates.

  First, a description will be given of the maximum load operation in which the refrigerant flows through both the heat source side heat exchangers 1a and 1b during the cooling operation. The high-temperature and high-pressure refrigerant compressed by the compressor 2 flows to the header 3a via the four-way valve 21. The refrigerant flows into the heat source side heat exchangers 1a and 1b through the refrigerant pipe divided into two by the header 3a, and the low-temperature and high-pressure refrigerant that exchanges heat with the air that the fans 6a and 6b blow in forward rotation respectively is the header 3b. After joining, it flows to the indoor unit. The refrigerant is depressurized by the depressurization means 22a, becomes low temperature and low pressure, and flows into the use side heat exchanger 22. In a multi-unit type air conditioner in which a plurality of indoor units are connected to a single outdoor unit, refrigerant piping is provided before and after the use side heat exchanger 22 and the decompression means 22a so that the refrigerant flows to each indoor unit. Branched. The refrigerant that has been subjected to heat exchange in the use-side heat exchanger 22 and has become high temperature and low pressure flows into the compressor 2 through the four-way valve 21. The header 3 shown in FIG. 1 includes a header 3a and a header 3b. The decompression means 22a is an electromagnetic valve whose capillary tube and opening degree can be adjusted.

  Next, the maximum load operation in which the refrigerant flows through both the heat source side heat exchangers 1a and 1b during the heating operation will be described. The high-temperature and high-pressure refrigerant compressed by the compressor 2 flows into the use side heat exchanger 22 of the indoor unit via the four-way valve 21 and exchanges heat with the indoor air to become a low-temperature and high-pressure refrigerant. Thereafter, the refrigerant becomes low temperature and low pressure by the decompression means 22a, and flows into the heat source side heat exchangers 1a and 1b through the refrigerant pipe divided into two by the header 3b. The refrigerant that exchanges heat with the air blown by the fans 6a and 6b in the forward rotation in the heat source side heat exchangers 1a and 1b becomes high temperature and low pressure, merges in the header 3a, and then flows into the compressor 2 via the four-way valve 21. .

  Here, the refrigerant flow during the cooling operation during the partial load operation and during the heating operation will be described. An opening / closing valve 23 is provided in the refrigerant pipe between the heat source side heat exchanger 1b and the header 3b. When the on-off valve 23 is opened, the refrigerant flows, and when it is closed, the refrigerant does not flow. During the partial load operation, the refrigerant flowing to the heat source side heat exchanger 1b is stopped by closing the on-off valve 23 during both the cooling operation and the heating operation. In this case, the fan 6b is stopped and the fan 6a is driven in forward rotation. In addition, if an on-off valve is further provided between the header 3a and the heat source side heat exchanger 1b, accumulation of refrigerant in the heat source side heat exchanger 1b can be prevented during partial load operation. When switching to partial load operation during cooling operation, it is preferable to close the on-off valve 23 after closing the on-off valve provided between the header 3a and the heat source side heat exchanger 1b, and close the on-off valve 23 first during heating operation. Good.

  As described above, the air conditioner according to the first embodiment has the heat sink 5 disposed below the fan 6a that is driven during both the maximum load operation and the partial load operation. The temperature rise of the substrate 4b can be prevented. Moreover, since the fan 6b is stopped, the operating efficiency of the air conditioner during partial load operation can be increased.

  Further, during partial load operation, the refrigerant flows only to the heat source side heat exchanger 1a and stops the refrigerant flowing to the heat source side heat exchanger 1b, so that the heat exchange amount of the heat source side heat exchanger is too large and is used in the cooling operation. It is possible to prevent the refrigerant temperature from being extremely lowered at the inlet of the side heat exchanger and the refrigerant flow noise from being generated from the piping around the decompression means 22a. Further, in the case of heating operation, it is possible to prevent the refrigerant pressure discharged from the compressor 2 from rising excessively. Further, since the fan 6b is stopped during the partial load operation, the operation efficiency can be increased.

Embodiment 2. FIG.
In the second embodiment, the outdoor unit 10 when the fan 6b is driven in the reverse rotation during the partial load operation will be described with reference to FIGS. FIG. 7 is a front view of the outdoor unit 10 of the air conditioner when the fan 6b of the second embodiment is reversely rotated, and FIG. 8 is a top view. In addition, the structure of the air conditioning apparatus in this Embodiment 2 is the same as that of Embodiment 1, and attaches | subjects the same code | symbol to the same part.

  During the partial load operation, the refrigerant flows through the heat source side heat exchanger 1a but does not flow through the heat source side heat exchanger 1b. The fan 6a is driven by forward rotation, and in the second embodiment, the fan 6b is driven by reverse rotation. As shown in FIG. 7, when the fan 6b is rotated in the reverse direction, the wind blown by the fan 6b is reversed during forward rotation, and the air is sucked from above the fan 6b and blown downward. As shown in FIG. 8, the air sucked from above the fan 6b is exhausted from the inside to the outside of the heat source side heat exchanger 1b. Since a part of the exhausted air passes through the central portion of the outdoor unit 10 and flows to the heat source side heat exchanger 1a and then blown to the fan 6a, the flow rate of the air flowing inside the heat source side heat exchanger 1a is To increase.

  Since wind flows from the heat source side heat exchanger 1b to the heat source side heat exchanger 1a, if the heat sink 5 is arranged on the right side of the center of the control box 4, the wind flowing from the heat source side heat exchanger 1b is efficiently applied to the heat sink 5. The heat radiation amount of the heat sink 5 can be increased.

  In the second embodiment, a temperature detection circuit for detecting the temperature of the control board 4b is built in the control board 4b, or a temperature detection means such as a thermistor or a thermocouple is attached to the heat sink 5 instead of the temperature / temperature detection circuit. The fan 6b is stopped when the temperature detected by the temperature detecting means during the load operation is equal to or lower than a predetermined value. However, the control board 4b may drive the fan 6b in the reverse rotation when the temperature is higher than the predetermined value.

  Further, if the fan 6b is driven by the DC power output from the converter circuit built in the control board 4a instead of the AC power output from the inverter circuit, the amount of heat generated by the control board 4b by driving the fan 6b is reduced. Can be lowered.

  As described above, the air conditioner of the second embodiment creates the airflow that reversely rotates the fan 6b during the partial load operation and flows from the heat source side heat exchanger 1b side to the heat source side heat exchanger 1a side. The amount of air hitting the heat increases, and the heat dissipation amount of the heat sink 5 can be increased.

  Here, the operation method of the air conditioning apparatus of Embodiment 1 and Embodiment 2 is demonstrated using the flowchart of FIG. First, when the operation of the air conditioner is started, the control board 4b calculates the operation capacity of the compressor 2 to determine whether it is a partial load operation or a maximum load operation (S10). If it is determined that the maximum load operation is performed in S10, the process proceeds to S11. In S11, the control board 4b controls to drive the fan 6a and the fan 6b in forward rotation, and controls the on-off valve 23 to open and flow the refrigerant through both the heat source side heat exchanger 6a and the heat source side heat exchanger 6b. If it is determined that the partial load operation is performed in S10, the process proceeds to S12. In S12, the control board 4b controls to stop the fan 6b, drives the fan 6a by forward rotation, controls the on-off valve 23 to close, and stops the refrigerant flowing to the heat source side heat exchanger 6b. After S12, the process proceeds to S13. In S13, the control board 4b determines whether the detected value of the temperature detecting means for detecting the temperature of the control board 4b or the heat sink 5 is greater than or equal to a predetermined value. If the detected value is equal to or smaller than the predetermined value in S13, the process returns to S10. If it is determined that the detected value is equal to or larger than the predetermined value, the process proceeds to S14. In S14, the control board 4b controls to drive the fan 6b in the reverse rotation.

In S12, an operation method may be used in which the control board 4b rotates in the reverse direction without stopping the fan 6b and returns to S10 without shifting to S13.
Note that the control performed by the control board 4b in S14 may be performed in S12, and after S12, S13 may be omitted and the process may return to S10. Further, when the fan 6b is configured to be driven not by the AC power output from the inverter circuit 4c but by the DC power or commercial AC power output by the converter circuit built in the control board 4a, the control board by driving the fan 6b. The calorific value of 4b can be reduced.

  As described above, since the operation method of the air conditioning apparatus according to the first and second embodiments drives the fan 6a during both the maximum load operation and the partial load operation, the fan 6a is driven. The heat sink 5 disposed below can be efficiently radiated. Moreover, since the fan 6b is reversely rotated to increase the amount of air blown by the fan 6a, the heat dissipation amount of the heat sink 5 can be increased.

Embodiment 3 FIG.
In the third embodiment, a case in which a low-temperature refrigerant is supplied to the heat source side heat exchanger 1b during partial load operation during cooling operation to drive the fan 6b in forward rotation will be described with reference to FIGS. FIG. 10 is a refrigerant circuit diagram showing a refrigerant flow during the cooling / heating operation in the third embodiment. FIG. 11 is a refrigerant circuit diagram illustrating the flow of the refrigerant when the refrigerant flows through the heat source side heat exchanger 1b during the partial load operation of the cooling operation. The solid line arrows in the figure indicate the refrigerant flow during the cooling operation, and the broken line arrows in the figure indicate the refrigerant flow during the heating operation. In addition, the same code | symbol is attached | subjected to the structure of the air conditioning apparatus in this Embodiment 3, and the same part of Embodiment 1. FIG.

  In addition to the configuration of the first embodiment, the air conditioner of the third embodiment includes a second four-way valve 24, a pipe through which refrigerant flows from the first four-way valve 21 to the compressor 2, and a second four-way valve 24. A connecting pipe 25, a header 3b, a pipe of the pressure reducing means 22a, a branch pipe 26 connecting the on-off valve 23, and a pressure reducing means 27 provided in the branch pipe 26 are provided. The on-off valve 23 according to the third embodiment is a three-way valve provided at a connection point between a pipe connecting the heat source side heat exchanger 1b and the header 3b and the branch pipe 26.

First, the flow of the refrigerant in the maximum load operation in which the refrigerant is supplied to both the heat source side heat exchangers 1a and 1b during the cooling operation and the heating operation in the third embodiment will be described based on FIG.
During the cooling operation, the high-temperature and high-pressure refrigerant compressed by the compressor 2 flows to the header 3a via the four-way valve 21. One of the refrigerant pipes divided into two by the header 3 a is connected to the heat source side heat exchanger 1 a, and the other one is connected to the heat source side heat exchanger 1 b via the second four-way valve 24. The refrigerant that has flowed into the heat source side heat exchangers 1a and 1b exchanges heat with the air blown by the fans 6a and 6b in forward rotation, respectively, and becomes low-temperature and high-pressure refrigerant. The refrigerant flowing out from the heat source side heat exchangers 1a and 1b joins in the header 3b and then flows to the indoor unit. At this time, the valve on the branch pipe 26 side of the on-off valve 23 and the pressure reducing means 27 are closed so that the refrigerant does not flow into the branch pipe 26. The refrigerant is depressurized by the depressurization means 22a, becomes low temperature and low pressure, and flows into the use side heat exchanger 22. The refrigerant that has been subjected to heat exchange in the use-side heat exchanger 22 and has become high temperature and low pressure flows into the compressor 2 through the four-way valve 21.

  At the time of heating operation, the high-temperature and high-pressure refrigerant compressed by the compressor 2 flows into the use side heat exchanger 22 of the indoor unit via the four-way valve 21 and exchanges heat with room air to become a low-temperature and high-pressure refrigerant. Thereafter, the refrigerant becomes low temperature and low pressure by the decompression means 22a, and flows into the heat source side heat exchangers 1a and 1b through the refrigerant pipe divided into two by the header 3b. At this time, the valve on the branch pipe 26 side of the on-off valve 23 and the pressure reducing means 27 are closed so that the refrigerant does not flow into the branch pipe 26. In the heat source side heat exchangers 1a and 1b, the refrigerants that exchange heat with the air that the fans 6a and 6b blow in forward rotation respectively have high temperature and low pressure. The refrigerant flowing out from the heat source side heat exchanger 1a returns to the compressor 2 via the header 3a and the four-way valve 21, and the refrigerant flowing out from the heat source side heat exchanger 1b passes through the connection pipe 25 via the second four-way valve 24. Return to the compressor 2 through.

  In the third embodiment, as in the second embodiment, a temperature detection circuit for detecting the temperature of the control board 4b is built in the control board 4b. When the temperature detected by the temperature detection circuit during the partial load operation is below a predetermined value, the refrigerant flowing to the heat source side heat exchanger 1b is stopped by closing all the valves of the on-off valve 23 during both the cooling operation and the heating operation. Yes. In that case, the fan 6b is stopped or rotating in reverse, and the fan 6a is driven in forward rotation. When the temperature detected by the temperature detection circuit during the partial load operation during the cooling operation becomes equal to or higher than a predetermined value, a low-temperature refrigerant flows through the heat source side heat exchanger 1b, and the fan 6b rotates forward. The operation will be described below with reference to FIG.

  When the temperature detected by the temperature detection circuit exceeds a predetermined value, the valve on the branch pipe 26 side of the on-off valve 23 and the valve on the heat source side heat exchanger 1b open, and the refrigerant flows from the branch pipe 26 to the heat source side heat exchanger 1b. . The high-temperature and high-pressure refrigerant compressed by the compressor 2 flows into the header 3a via the four-way valve 21. One of the refrigerant pipes divided into two by the header 3a is connected to the heat source side heat exchanger 1a. The other one is connected to the four-way valve 24. However, since the refrigerant pipe is closed at the tip of the four-way valve 24, the refrigerant flows only to the heat source side heat exchanger 1a. The refrigerant that has flowed through the heat source side heat exchanger 1a exchanges heat with air that is blown forward by the fan 6a to become a low-temperature and high-pressure refrigerant. Thereafter, the refrigerant flows to the decompression means 22a and the use side heat exchanger 22 via the header 3b, but a part of the refrigerant flows to the branch pipe 26 connected between the header 3b and the decompression means 22a. The refrigerant flowing through the branch pipe 26 is decompressed by the decompression means 27 provided in the branch pipe 26 to become a low-temperature and low-pressure refrigerant. The low-temperature and low-pressure refrigerant flows to the heat source side heat exchanger 1b through the on-off valve 23 provided between the heat source side heat exchanger 1b and the header 3b. The refrigerant flowing through the heat source side heat exchanger 1b exchanges heat with the air blown by the fan 6b in the forward rotation to become a high-temperature and low-pressure refrigerant. The refrigerant flowing out from the heat source side heat exchanger 1 b flows through the connection pipe 25 via the second four-way valve 24 and returns to the compressor 2. The refrigerant that has passed through the pressure reducing means 22 a and the use side heat exchanger 22 from the header 3 b joins with the refrigerant flowing from the connection pipe 25 via the four-way valve 21 and returns to the compressor 2.

  As described above, the air-conditioning apparatus according to Embodiment 3 can flow a low-temperature refrigerant to the heat source side heat exchanger 1b of the outdoor unit 10 even during the cooling operation, and lowers the air temperature inside the outdoor unit 10. Therefore, the heat dissipation of the heat sink 5 can be increased and the temperature rise of the control board 4b can be prevented. Further, by increasing the rotational speed of the fan 6a from the rotational speed of the fan 6b, the air volume of the low-temperature air passing through the central portion of the outdoor unit 10 is increased without changing the air volume flowing through the heat source side heat exchanger 1a, thereby efficiently The heat sink can be cooled.

  Next, the operation method of the air conditioner of Embodiment 3 will be described with reference to FIG. First, when the operation of the air conditioner is started and the cooling operation is performed (S2), the process proceeds to S20. In S20, the control board 4b calculates the operation capacity of the compressor 2 to determine whether the control board 4b is a partial load operation or a maximum load operation (S20). If it is determined in S20 that the operation is at the maximum load, the process proceeds to S21. In S21, the control board 4b controls to drive the fan 6a and the fan 6b in forward rotation. Further, the control board 4b switches the four-way valve 24 to connect the header 3a and the heat source side heat exchanger 1b, opens the on-off valve 23, and allows the refrigerant to flow through both the heat source side heat exchanger 6a and the heat source side heat exchanger 6b. . After S21, the process returns to S20. If it is determined that the partial load operation is performed in S20, the process proceeds to S22. In S22, the control board 4b controls to stop the fan 6b, drives the fan 6a by forward rotation, controls the on-off valve 23 to close, and stops the refrigerant flowing to the heat source side heat exchanger 6b. After S22, the process proceeds to S23. In S23, the control board 4b determines whether the detected value of the temperature detecting means for detecting the temperature of the control board 4b or the heat sink 5 is greater than or equal to a predetermined value. If the detected value is equal to or smaller than the predetermined value in S23, the process returns to S20. If it is determined that the detected value is equal to or larger than the predetermined value, the process proceeds to S24. In S24, the control board 4b controls to drive the fan 6a and the fan 6b by forward rotation. Further, the control board 4b switches the four-way valve 24 to connect the heat source side heat exchanger 1b and the connection pipe 25. Further, the control board 4b opens the on-off valve 23 so that the refrigerant flows from the branch pipe 26 to the heat source side heat exchanger 1b. Under the control of S24, the high-temperature and high-pressure refrigerant discharged from the compressor 2 becomes the low-temperature and high-pressure refrigerant in the heat source side heat exchanger 1a, and then the low-temperature and low-pressure refrigerant decompressed by the decompression means 27 provided in the branch pipe 26 is used as the heat source. It can flow to the side heat exchanger 1b.

  Note that the control performed by the control board 4b in S24 may be performed in S22, and S23 may be omitted after S22 and the process may return to S20. Further, when the fan 6b is configured to be driven not by the AC power output by the inverter circuit but by the DC power or the commercial AC power output by the converter circuit built in the control board 4a, the control board 4b by driving the fan 6b. The amount of heat generated can be reduced.

  As described above, the operation method of the air-conditioning apparatus according to Embodiment 3 is arranged under the fan 6a because the fan 6a is driven during both the maximum load operation and the partial load operation. Heat dissipation of the heat sink 5 can be performed efficiently. In addition, since the low-temperature and low-pressure refrigerant is caused to flow through the heat source side heat exchanger 6b during the cooling operation to lower the temperature inside the outdoor unit 10, the heat radiation amount of the heat sink 5 can be increased.

  The present invention can be used for an air conditioner including an outdoor unit.

  1a, 1b Heat source side heat exchanger, 2 compressor, 3 header, 4 control box, 4a housing, 4b control board, 4c inverter circuit, 5 heat sink, 5a base, 5b fin, 6a, 6b fan, 6c blade, 7a , 7b Fan guard, 10 Outdoor unit, 11a, 11b Pillar, 12a Bottom plate, 12b Top plate, 13 Front panel, 14a Left side, 14b Right side, 15 Back, 21 Four-way valve, 22 Utilization side heat exchanger, 22a Pressure reducing means , 23 On-off valve, 24 Second four-way valve, 25 Connection pipe, 26 Separation pipe, 27 Pressure reducing means.

Claims (9)

A housing having an opening on a side surface;
A compressor installed inside the housing;
A control device having an inverter circuit to control the compressor;
A first heat exchanger through which refrigerant flows during partial load operation where the operating capacity of the compressor is a predetermined value or less;
A second heat exchanger in which refrigerant does not flow during the partial load operation;
A first blower that is provided above the first heat exchanger and blows air to the first heat exchanger during the partial load operation;
A second blower provided above the second heat exchanger and stopped during the partial load operation;
A heat sink that cools the controller provided below the end of the blade of the first blower and provided at the top of the housing;
An outdoor unit characterized by comprising: A housing having an opening on a side surface;
A compressor installed inside the housing;
A control device having an inverter circuit to control the compressor;
A first heat exchanger through which refrigerant flows during partial load operation where the operating capacity of the compressor is a predetermined value or less;
A second heat exchanger in which refrigerant does not flow during the partial load operation;
A first blower which is provided above the first heat exchanger and blows air from the bottom to the top by forward rotation during the partial load operation;
A second blower that is provided above the second heat exchanger and blows from top to bottom in reverse rotation during the partial load operation;
A heat sink that cools the controller provided below the end of the blade of the first blower and provided at the top of the housing;
An outdoor unit characterized by comprising: A housing having an opening on a side surface;
A compressor installed inside the housing;
A control device having an inverter circuit to control the compressor;
A first heat exchanger through which a high-temperature and high-pressure refrigerant compressed by the compressor flows during partial load operation in which the operation capacity of the compressor is a predetermined value or less;
Decompression means for decompressing the refrigerant that has been subjected to heat exchange in the first heat exchanger during the partial load operation to become a low temperature and high pressure;
A second heat exchanger through which the refrigerant that has passed through the pressure-reducing means and became low-temperature and low-pressure flows during the partial load operation;
A first blower that is provided above the first heat exchanger and blows air to the first heat exchanger during the partial load operation;
A second blower that is provided above the second heat exchanger and blows air to the second heat exchanger during the partial load operation;
A heat sink that cools the controller provided below the end of the rotating blade of the first blower and provided at the top of the housing;
An outdoor unit characterized by comprising: A temperature detecting means for detecting the temperature of the control device or the heat sink;
The said 2nd air blower stops when the detection value of the said temperature detection means is below a predetermined value, and reversely rotates the said 2nd air blower when it is more than a predetermined value. Outdoor unit. The outdoor unit of an air conditioner according to claim 2 or 3, wherein the second blower is driven by DC power or commercial AC power. The outdoor unit according to any one of claims 1 to 3, wherein the control device determines that the partial load operation is performed when a frequency of a voltage applied from the inverter circuit to the compressor is a predetermined value or less. An outdoor unit for an air conditioner according to any one of claims 1 to 3, comprising a four-way valve that switches between a cooling operation and a heating operation.
A user-side heat exchanger connected to the four-way valve to cool and heat the room;
An air conditioner comprising: A housing having an opening on a side surface;
A compressor installed inside the housing;
A first blower that is provided above the first heat exchanger and blows air to the first heat exchanger;
A second blower that is provided above the second heat exchanger and blows air to the second heat exchanger;
A heat sink that cools the controller provided below the end of the blade of the first blower and provided at the top of the housing;
An on-off valve that opens and closes the flow path of the refrigerant flowing through the second heat exchanger;
A four-way valve that switches between cooling operation and heating operation,
A control device for controlling the compressor, the first blower, the second blower, the on-off valve, and the four-way valve;
A user-side heat exchanger connected to the four-way valve to cool and heat the room;
In the operation method of the air conditioner equipped with
Maximum load for driving the first fan and the second fan by causing the control device to open the on-off valve to flow a refrigerant through the first heat source side heat exchanger and the second heat source side heat exchanger. Operation process;
A partial load in which the control device closes the on-off valve, causes a refrigerant to flow through the first heat source side heat exchanger, drives the second fan, and stops or reversely rotates the second fan. Operation process;
A method for operating an air conditioner, comprising: A housing having an opening on a side surface;
A compressor installed inside the housing and discharging a high-temperature and high-pressure refrigerant;
A four-way valve connected to the compressor to switch between cooling operation and heating operation;
A control device having an inverter circuit to control the compressor;
A first blower that is provided above the first heat exchanger and blows air to the first heat exchanger;
A second blower that is provided above the second heat exchanger and blows air to the second heat exchanger;
A heat sink that cools the controller provided below the end of the rotating blade of the first blower and provided at the top of the housing;
A branch pipe in which heat is exchanged in the first heat exchanger during the partial load operation and the low-temperature and high-pressure refrigerant flows into the second heat exchanger;
A decompression means provided in the branch pipe for decompressing the low-temperature high-pressure refrigerant;
An on-off valve that opens and closes the flow path of the refrigerant flowing through the second heat exchanger;
A control device for controlling the compressor, the first blower, the second blower, the on-off valve, and the four-way valve;
A user-side heat exchanger connected to the four-way valve to cool and heat the room;
In the operation method of the air conditioner equipped with
Maximum load for driving the first fan and the second fan by causing the control device to open the on-off valve to flow a refrigerant through the first heat source side heat exchanger and the second heat source side heat exchanger. Operation process;
A partial load operation step in which the control device controls the on-off valve to flow the low-temperature and low-pressure refrigerant through the first heat exchanger, and drives the first blower and the second blower;
A method for operating an air conditioner, comprising:

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