JP4513848B2 - Air conditioner and control method of air conditioner - Google Patents

Description

  The present invention relates to an air conditioner and an air conditioner control method.

  Conventionally, as an air conditioner, when switching a pilot-type four-way valve that switches the refrigerant flow in the refrigerant circuit, it is necessary to ensure the differential pressure before and after the four-way valve to switch reliably. There is one that performs four-way valve operation guarantee control for operating a compressor for a predetermined time at a frequency (for example, see Japanese Patent Publication No. 3-7858 (Patent Document 1)).

  In this air conditioner, the four-way valve is switched by the four-way valve operation guarantee control when changing from the cooling cycle to the heating cycle or from the heating cycle to the cooling cycle. Even in the cycle, the four-way valve operation guarantee control is performed every time because the previous operation mode is unknown.

In such an air conditioner, since the operation frequency of the compressor is operated at a predetermined value or higher in the four-way valve operation guarantee control, the refrigerant passing sound is generated during the cooling operation or the indoor fan rotor is dewed and water splashes. There's a problem.
No. 3-7858

  Therefore, an object of the present invention is to provide an air conditioner and an air conditioner that can suppress generation of refrigerant passing sound and water splash due to condensation without performing four-way valve operation guarantee control as much as possible when starting the compressor after the power is turned off. It is to provide a method for controlling the machine.

In order to solve the above problems, the air conditioner of the present invention is
A refrigerant circuit including a compressor and a pilot-type four-way valve that switches a flow of refrigerant discharged from the compressor;
A control unit for controlling the four-way valve and the compressor;
A non-volatile storage unit that stores the position information of the four-way valve when operation is stopped,
The control unit
Before starting operation after turning on the power, in order to ensure the differential pressure before and after the four-way valve of the refrigerant circuit, four-way valve operation guarantee control is performed to operate the four-way valve by operating the compressor at a predetermined frequency. Has the ability to
If the position information of the four-way valve read from the nonvolatile storage unit does not correspond to the next operation mode when starting the next compressor after power off, the four-way valve operation assurance control is performed to While switching the four-way valve to a position corresponding to the next operation mode, when the position information of the four-way valve read from the nonvolatile storage unit corresponds to the next operation mode, the four-way valve operation guarantee With no control,
The position information of the four-way valve to be written in the non-volatile storage unit includes a cooling position at the time of cooling operation, a heating position at the time of heating operation, and an indefinite position when it is not determined whether it is the cooling position or the heating position. And the position information of any one of the cooling position, the heating position, and the indefinite position is written to the nonvolatile storage unit,
The cooling position, the heating position, and the indefinite position are defined as follows: in the four-way valve that energizes the coil of the four-way valve during heating operation, the operation mode according to either the heating cycle or the cooling cycle, and the compressor is It is determined based on the state of the four-way valve operation guarantee control that operates at the frequency and operates the four-way valve,
When the operation mode is the cooling cycle or the heating cycle, the four-way valve operation guarantee control is operating or stopped during operation, the position information of the four-way valve is set to the indefinite position,
When the operation mode is a cooling cycle, the operation after the operation of the four-way valve operation guarantee control or the stop after the operation , the position information of the four-way valve is the cooling position,
After the operation of the four-way valve operation guarantee control when the operation mode is a heating cycle, the position information of the four-way valve is the heating position,
When the operation mode is a heating cycle, if the coil of the four-way valve is in an energized state within a certain period of time after the operation of the four-way valve operation guarantee control, the position information of the four-way valve is displayed . The heating position,
When the operation mode is a heating cycle, the position information of the four-way valve is set to the indefinite position after the fixed time has elapsed since the stop after the operation of the four-way valve operation guarantee control.

  Here, power off includes a mode (hereinafter referred to as standby power saving) in which the power of the outdoor unit is turned off during operation stop to save standby power.

According to the air conditioner having the above configuration, the nonvolatile storage unit stores the positional information of the four-way valve when the operation is stopped, so that it is nonvolatile even when the compressor is started after power-off or standby power saving. Since the previous refrigeration cycle is known from the position information of the four-way valve stored in the storage unit, the four-way valve operation guarantee control need not be performed when the previous and current refrigeration cycles are the same. Therefore, at the time of starting the compressor after the power is turned off, it is possible to suppress generation of refrigerant passing sound and water splash due to condensation without performing the four-way valve operation guarantee control as much as possible. In addition, an energization mode of either energizing the coil of the four-way valve during heating operation or energizing the coil of the four-way valve during cooling operation, and an operation mode by either the heating cycle or the cooling cycle, Based on the state of the four-way valve operation guarantee control that operates the four-way valve by operating the compressor at a predetermined frequency, the position information (cooling position, heating position, indefinite position) of the four-way valve to be written in the nonvolatile storage unit By deciding, it is possible to store accurate positional information of the four-way valve when the operation is stopped in the nonvolatile storage unit.

  Moreover, in the air conditioner of one Embodiment, the positional information which shows that it is indefinite regardless of the position of the said four-way valve is memorize | stored in the said non-volatile memory | storage part at the time of shipment.

  The four-way valve is shipped at either position after testing the heating operation or cooling operation at the factory, but the switching position of the four-way valve may be shifted due to vibration during transportation. Therefore, according to the embodiment, at the time of shipment, the non-volatile storage unit is stored in the non-volatile storage unit by storing position information indicating indefinite regardless of the position of the four-way valve in the non-volatile storage unit. Because the position information (undefined position) of the four-way valve read out from does not correspond to the next operation mode, the four-way valve operation guarantee control is always performed, so the operation must be started with the four-way valve position shifted. And reliability is improved.

  Moreover, in the air conditioner of one Embodiment, the said control part writes the present positional information on the said four-way valve obtained based on the driving | running | working state in driving | operation to the said non-volatile memory | storage part at the time of operation stop.

  According to the above embodiment, the current position information of the four-way valve obtained based on the operating state during operation is written into the nonvolatile storage unit by the control unit when the operation is stopped, so that the accuracy when the operation is stopped The position information of the four-way valve can be stored in the nonvolatile storage unit.

Moreover, in the air conditioner of one embodiment,
The control unit
While operating the compressor at the predetermined frequency while energizing the coil of the four-way valve during heating operation, the four-way valve is switched so that the refrigerant flow in the refrigerant circuit becomes a heating cycle,
By operating the compressor at the predetermined frequency without energizing the coil of the four-way valve during cooling operation, the four-way valve is switched so that the refrigerant flow in the refrigerant circuit becomes a cooling cycle.

  According to the embodiment, in the four-way valve operation guarantee control, the refrigerant flow in the refrigerant circuit can be reliably switched by energization or non-energization of the coil of the four-way valve in accordance with the refrigeration cycle.

Moreover, in the air conditioner of one embodiment,
The control unit
While operating the compressor at the predetermined frequency while energizing the coil of the four-way valve during cooling operation, the four-way valve is switched so that the refrigerant flow in the refrigerant circuit becomes a cooling cycle,
By operating the compressor at the predetermined frequency without energizing the coil of the four-way valve during the heating operation, the four-way valve is switched so that the refrigerant flow in the refrigerant circuit becomes a heating cycle.

  According to the embodiment, in the four-way valve operation guarantee control, the refrigerant flow in the refrigerant circuit can be reliably switched by energization or non-energization of the coil of the four-way valve in accordance with the refrigeration cycle.

In the control method of the air conditioner of the present invention,
A refrigerant circuit through which refrigerant discharged from the compressor circulates, a pilot-type four-way valve for switching the flow of refrigerant in the refrigerant circuit, a control unit for controlling the four-way valve and the compressor, and the above-mentioned when the operation is stopped A control method for an air conditioner including a nonvolatile storage unit that stores positional information of a four-way valve,
When the position of the four-way valve read from the nonvolatile storage unit does not correspond to the next operation mode at the time of starting the next compressor after the power is turned off by the control unit, the compressor is set at a predetermined frequency. Performing a four-way valve operation guarantee control to switch the four-way valve to a position corresponding to the next operation mode by operating and operating the four-way valve,
The position information of the four-way valve to be written in the non-volatile storage unit includes a cooling position at the time of cooling operation, a heating position at the time of heating operation, and an indefinite position when it is not determined whether it is the cooling position or the heating position. And the position information of any one of the cooling position, the heating position, and the indefinite position is written to the nonvolatile storage unit,
The cooling position, the heating position, and the indefinite position are defined as follows: in the four-way valve that energizes the coil of the four-way valve during heating operation, the operation mode according to either the heating cycle or the cooling cycle, and the compressor is It is determined based on the state of the four-way valve operation guarantee control that operates at the frequency and operates the four-way valve,
When the operation mode is the cooling cycle or the heating cycle, the four-way valve operation guarantee control is operating or stopped during operation, the position information of the four-way valve is set to the indefinite position,
When the operation mode is a cooling cycle, the operation after the operation of the four-way valve operation guarantee control or the stop after the operation , the position information of the four-way valve is the cooling position,
After the operation of the four-way valve operation guarantee control when the operation mode is a heating cycle, the position information of the four-way valve is the heating position,
When the operation mode is a heating cycle, if the coil of the four-way valve is in an energized state within a certain period of time after the operation of the four-way valve operation guarantee control, the position information of the four-way valve is displayed . The heating position,
When the operation mode is a heating cycle, the position information of the four-way valve is set to the indefinite position after the fixed time has elapsed since the stop after the operation of the four-way valve operation guarantee control.

  According to the control method for the air conditioner, the position information of the four-way valve is stored in the nonvolatile storage unit when the operation is stopped, so that even when the compressor is started after the power is turned off or the standby power is saved. Since the previous refrigeration cycle is known from the position information of the four-way valve stored in the sexual storage unit, it is not necessary to perform the four-way valve operation guarantee control when the previous and current refrigeration cycles are the same. Therefore, at the time of starting the compressor after the power is turned off, it is possible to suppress generation of refrigerant passing sound and water splash due to condensation without performing the four-way valve operation guarantee control as much as possible. In addition, at the time of shipment, regardless of the position of the four-way valve, the four-way valve operation guarantee control is always performed in the trial operation after installation by storing the position information indicating indefinite in the nonvolatile storage unit. The operation is not started in a state where the position of the four-way valve is shifted, and the reliability is improved.

As is clear from the above, according to the air conditioner of the present invention, when the compressor is turned on after the power is turned off, the four-way valve operation guarantee control is not performed as much as possible, and the generation of refrigerant passing sound or water splashing due to condensation is performed. An air conditioner that can suppress the above can be realized. In addition, an energization mode of either energizing the coil of the four-way valve during heating operation or energizing the coil of the four-way valve during cooling operation, and an operation mode by either the heating cycle or the cooling cycle, Based on the four-way valve operation guarantee control that operates the four-way valve by operating the compressor at a predetermined frequency, determine the position information (cooling position, heating position, undefined position) of the four-way valve to be written to the nonvolatile storage unit Thus, the accurate positional information of the four-way valve when the operation is stopped can be stored in the nonvolatile storage unit.

  In addition, according to the air conditioner of one embodiment, at the time of shipment, the position information indicating indefinite is stored in the nonvolatile storage unit regardless of the position of the four-way valve. Since the four-way valve operation guarantee control is always performed, the operation is not started in a state where the position of the four-way valve is shifted, and the reliability is improved.

  Further, according to the air conditioner of one embodiment, by writing the current four-way valve position information obtained based on the operating state during operation into the nonvolatile storage unit by the control unit when operation is stopped, Accurate four-way valve position information when the operation is stopped can be stored in the nonvolatile storage unit.

  Further, according to the air conditioner of one embodiment, in the four-way valve operation assurance control, the compressor is operated at a predetermined frequency while the coil of the four-way valve is energized during heating operation. By switching the four-way valve so that the flow of the refrigerant becomes a heating cycle, the refrigerant flow in the refrigerant circuit is changed to the cooling cycle by operating the compressor at a predetermined frequency without energizing the coil of the four-way valve during the cooling operation. By switching the four-way valve in such a manner, the refrigerant flow in the refrigerant circuit can be reliably switched by energization or non-energization of the coil of the four-way valve according to the refrigeration cycle.

  Further, according to the air conditioner of one embodiment, in the four-way valve operation guarantee control, by operating the compressor at a predetermined frequency while energizing the coil of the four-way valve during cooling operation, While switching the four-way valve so that the flow becomes the cooling cycle, the refrigerant flow in the refrigerant circuit becomes the heating cycle by operating the compressor at a predetermined frequency without energizing the coil of the four-way valve during heating operation. By switching the four-way valve in this way, the flow of the refrigerant in the refrigerant circuit can be switched reliably by energization and non-energization of the coil of the four-way valve according to the refrigeration cycle.

  Further, according to the control method for an air conditioner of the present invention, when starting the compressor after the power is turned off, the four-way valve operation guarantee control is not performed as much as possible, and the generation of refrigerant passing sound and water splash due to condensation are suppressed. In addition, at the time of shipment, regardless of the position of the four-way valve, the four-way valve operation guarantee control is always performed in the trial operation after installation by storing the position information indicating indefinite in the nonvolatile storage unit. The operation is not started in a state where the position of the four-way valve is shifted, and the reliability is improved.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an air conditioner and an air conditioner control method according to the present invention will be described in detail with reference to embodiments shown in the drawings.

  FIG. 1 shows a circuit diagram of a refrigerant circuit of an air conditioner according to an embodiment of the present invention. As shown in FIG. 1, this air conditioner has a compressor 1, a pilot-type four-way valve 2 with the discharge side of the compressor 1 connected to one end, and one end at the other end of the four-way valve 2. The connected outdoor heat exchanger 3, the electric expansion valve 4 having one end connected to the other end of the outdoor heat exchanger 3, and one end connected to the other end of the electric expansion valve 4 via a communication pipe L 1. An indoor heat exchanger 5 and an accumulator 6 having one end connected to the other end of the indoor heat exchanger 5 via a communication pipe L2 and a four-way valve 2 and the other end connected to the suction side of the compressor 1; It has. The compressor 1, the four-way valve 2, the outdoor heat exchanger 3, the electric expansion valve 4, the indoor heat exchanger 5 and the accumulator 6 constitute a refrigerant circuit.

  The air conditioner is disposed in the vicinity of the outdoor heat exchanger 3, the outdoor fan 7 that supplies outdoor air to the outdoor heat exchanger 3, the indoor fan 8 that is disposed in the vicinity of the indoor heat exchanger 5, and the compression EEPROM (electrically erasable and writable) as an example of a non-volatile storage unit that stores position information of the four-way valve 2 and a control unit 30 that controls the machine 1, the electric expansion valve 4, the outdoor fan 7, the indoor fan 8, and the like Read-only memory) 31. The control unit 30 includes a microcomputer, an input / output circuit, and the like, and includes a four-way valve operation guarantee timer TM1 and a power-off determination timer TM2.

  The compressor 1, the four-way valve 2, the outdoor heat exchanger 3, the electric expansion valve 4, the accumulator 6, the outdoor fan 7, the control unit 30 and the EEPROM 31 constitute the outdoor unit 10, and the indoor heat exchanger 5 and the indoor fan 8 Thus, the indoor unit 20 is configured.

  In the air conditioner having the above configuration, when the compressor 1 is started by switching the four-way valve 2 to the solid line switching position during the cooling operation, the high-pressure refrigerant discharged from the compressor 1 passes through the four-way valve 2 to the outdoor. Enters heat exchanger 3. The refrigerant condensed in the outdoor heat exchanger 3 is depressurized by the electric expansion valve 4 and then enters the indoor heat exchanger 5. The refrigerant evaporated in the indoor heat exchanger 5 returns to the suction side of the compressor 1 through the four-way valve 2 and the accumulator 6. In this way, the refrigerant circulates through the refrigerant circuit composed of the compressor 1, the outdoor heat exchanger 3, the electric expansion valve 4, the indoor heat exchanger 5, and the accumulator 6, so that the indoor heat exchanger 5 is The indoor air is circulated through the air to cool the room.

  On the other hand, at the time of heating operation, the four-way valve 2 is switched to the dotted line switching position, and is composed of the compressor 1, the indoor heat exchanger 5, the electric expansion valve 4, the outdoor heat exchanger 3, and the accumulator 6. The room is heated by circulating the refrigerant in the refrigerant circuit.

  2 shows a flowchart for explaining the operation of the control unit 30 of the air conditioner, FIG. 3 shows a flowchart following FIG. 2, and FIG. 4 shows a flowchart following FIG.

  First, when the process is started after the power is turned on, it is determined in step S1 shown in FIG. 2 whether or not there is an operation start request. If there is an operation start request, the process proceeds to step S2. Repeat S1.

  Next, the position information of the four-way valve 2 is read from the EEPROM 31 in step S2. Here, the position information of the four-way valve 2 is initially set to an indefinite position at the time of shipment.

  Next, it progresses to step S3, and if it determines with the positional information on the four-way valve 2 read by step S2 being a target four-way valve position (position corresponding to an operation mode), it will progress to step S11 of FIG. The target four-way valve position is the heating position in the heating operation mode by the heating cycle, and is the cooling position in the cooling operation and the dehumidifying operation by the cooling cycle.

  On the other hand, if it is determined that the position information of the four-way valve 2 read in step S2 is not the target four-way valve position, the process proceeds to step S4, and the four-way valve operation guarantee control is started in step S4. In this four-way valve operation guarantee control, the four-way valve 2 is switched to a position corresponding to the next operation mode by operating the compressor 1 at a predetermined frequency and operating the four-way valve 2.

  Next, the process proceeds to step S5, and the four-way valve operation guarantee timer TM1 is started. Here, the four-way valve operation guarantee timer TM1 is set to, for example, 30 seconds as the time for performing the four-way valve operation guarantee control.

  Next, the process proceeds to step S6, and when the four-way valve operation guarantee timer TM1 times out, the process proceeds to step S7, and the stored information of the four-way valve 2 is updated.

  On the other hand, when the four-way valve operation guarantee timer TM1 has not timed up in step S6, the process proceeds to step S8, where it is determined whether or not there is a stop request, and when there is no stop request, the process returns to step S6. If there is, the process proceeds to step S21 shown in FIG.

  Next, in step S11 shown in FIG. 3, the four-way valve operation guarantee control is finished and normal control is performed, and the process proceeds to step S12 to determine whether or not the operation mode has been changed.

  If it is determined in step S12 that there is a change in the operation mode, the process returns to step S4 shown in FIG. 2, while if it is determined that there is no change in the operation mode, the process proceeds to step S13.

  Next, in step S13, it is determined whether or not there is a stop request. If there is a stop request, the process proceeds to step S14. If there is no stop request, the process returns to step S11.

  Next, when it is a stop from air_conditionaing | cooling driving | operation by step S14, it progresses to step S22, sets four-way valve position information as a cooling position, and progresses to step S25.

  On the other hand, when the cooling operation is not stopped in step S14, the process proceeds to step S15.

  Then, after starting the power-off determination timer TM2 in step S15, the process proceeds to step S16 to determine whether or not the power-off determination timer TM2 has timed up. Here, the power-off determination timer TM2 is set to 3 minutes, for example.

  When the power-off determination timer TM2 times up in step S16, the process proceeds to step S23, and the four-way valve position information is set to an indefinite position, and the process proceeds to step S25. On the other hand, when the power-off determination timer TM2 has not expired in step S16, the process proceeds to step S24, and the four-way valve position information is set as the heating position, and the process proceeds to step S26.

  When it is determined in step S8 shown in FIG. 2 that there is no stop request, the process proceeds to step S21 shown in FIG. 3, and the four-way valve position information is set to an indefinite position, and the process proceeds to step S25.

  Next, in step S25, the four-way valve position information is written in the EEPROM 31, and the process proceeds to step S31 shown in FIG.

  In step S26, the four-way valve position information is written in the EEPROM 31, and the process proceeds to step S36 shown in FIG.

  Next, when it is determined in step S31 shown in FIG. 4 that the suspension has been entered, the process proceeds to step S33, whereas when it is determined that the suspension has not been entered, the process proceeds to step S32. Here, suspend is a function that cuts off the power supply to the outdoor unit in order to cut standby power when the operation is stopped. When the outdoor temperature is low in the heating season, the compressor is warmed up with priority given to heating start-up. Suspend function may not be activated due to preheating operation, but because the outdoor temperature is high during the cooling season, the suspend function operates almost during shutdown.

  In step S32, it is determined whether or not the power is off. If the power is off, the process proceeds to step S33. If the power is not off, the process proceeds to step S35.

  Next, the power is turned off, the microcomputer (the microcomputer in FIG. 4) used in the control unit 30 is reset in step S33, and the position information of the four-way valve 2 is held in the EEPROM 31 in step S34. This process ends.

  On the other hand, it is determined whether or not there is an operation start request in step S35, and when there is an operation start request, the process returns to step S2 shown in FIG. 2, while when there is no operation start request, the process returns to step S31.

  In step S36, it is determined whether or not there is an operation start request. When there is an operation start request, the process returns to step S2 shown in FIG. 2, while when there is no operation start request, the process proceeds to step S37.

  In step S37, it is determined whether or not the power is off. If the power is off, the process proceeds to step S33. If the power is not off, the process returns to step S16 shown in FIG.

  Next, FIG. 5 shows the relationship between the operation mode, the state of the four-way valve operation guarantee control, the coil energization of the four-way valve 2, and the position information of the four-way valve 2. FIG. 5 illustrates the four-way valve position when the coil of the four-way valve 2 is energized (turned on) during heating operation.

  As shown in FIG. 5, the state of the four-way valve operation guarantee control differs depending on the operation mode.

  Specifically, in the cooling operation and the dehumidifying operation by the cooling cycle, while the four-way valve operation guarantee control is operating, the four-way valve 2 coil is in a non-energized state (off) and the four-way valve position information is indefinite. After the operation of the four-way valve operation guarantee control, the coil of the four-way valve 2 is in a non-energized state (off) and the four-way valve position information is the cooling position.

  In the heating operation by the heating cycle, while the four-way valve operation guarantee control is in operation, the four-way valve 2 coil is energized (on) and the four-way valve position information is indefinite. After the operation, the coil of the four-way valve 2 is energized (ON) and the four-way valve position information is the heating position.

  In addition, when cooling is stopped from the cooling operation, the four-way valve operation guarantee control is stopped during operation. The four-way valve 2 coil is in a non-energized state (off) and the four-way valve position information is indefinite. After the operation of the guarantee control, the coil of the four-way valve 2 is in a non-energized state (off) and the four-way valve position information is the cooling position.

  In addition, when the four-way valve operation guarantee control is in operation after the heating operation is stopped, the coil of the four-way valve 2 is energized (on) within a certain time (3 minutes) from the stop, and the four-way valve switching position Is set to an indefinite position, and after a certain period of time (3 minutes) has elapsed since the stop during the operation of the four-way valve operation guarantee control, the coil of the four-way valve 2 is turned off and the four-way valve switching position is set to the indefinite position. And

  In addition, when the heating operation is stopped, the four-way valve operation guarantee control is stopped after the four-way valve operation guarantee control is activated within a certain time (three minutes). Is the heating position, and after a certain period of time (3 minutes) has elapsed since the stop of the four-way valve operation guarantee control, the four-way valve 2 coil is de-energized (off) and the four-way valve switching position is indefinite. And

  Thus, when energizing (turning on) the coil of the four-way valve 2 during the heating operation, the coil of the four-way valve 2 is not energized (off) during the cooling operation and during the stop. Also, if the coil of the four-way valve 2 is immediately de-energized (off) due to the stop from the heating operation, the four-way valve 2 is switched from the heating position to the cooling position, and the high pressure and low pressure of the refrigerant are reversed. Since sound is generated, the coil of the four-way valve 2 is deenergized (off) after 3 minutes. In addition, the position of the four-way valve 2 after about 3 minutes (a certain period of time) from the change in stoppage from the heating operation switches to the cooling position if there is a differential pressure, but remains in the heating position if there is no differential pressure. Since the cooling / heating position cannot be limited, the position is indefinite.

  According to the air conditioner and the air conditioner control method configured as described above, when the compressor 1 is started after the power is turned off (including standby power saving that saves standby power by turning off the outdoor unit during operation stop). Further, it is possible to suppress the generation of refrigerant passing sound and water splash due to condensation without performing the four-way valve operation guarantee control as much as possible.

  In addition, when this air conditioner is shipped, regardless of the position of the four-way valve 2, the position information indicating indefinite is stored in the EEPROM 31, so that the four-way valve operation guarantee control is always performed in the trial operation after installation. Therefore, even if the position of the four-way valve 2 is shifted due to vibration during transportation, the operation is not started in that state, and the reliability is improved.

  Further, an energization mode of either energizing the coil of the four-way valve 2 during the heating operation or energizing the coil of the four-way valve 2 during the cooling operation, and an operation mode based on either the heating cycle or the cooling cycle. And the position information (cooling position, heating position, indefinite position) of the four-way valve 2 to be written in the EEPROM 31 based on the four-way valve operation guarantee control for operating the compressor 1 at a predetermined frequency and operating the four-way valve 2. By deciding, the correct position information of the four-way valve 2 when the operation is stopped can be stored in the EEPROM 31.

  Further, the current position information of the four-way valve 2 obtained based on the operating state during operation is written into the EEPROM 31 by the control unit when the operation is stopped, so that the accurate position information of the four-way valve 2 when the operation is stopped is obtained. Can be stored in the EEPROM 31.

  In addition, using a four-way valve that energizes the coil during heating operation or a type that energizes the coil during cooling operation, the refrigerant flow in the refrigerant circuit is controlled by energizing or de-energizing the coil of the four-way valve according to the refrigeration cycle. It can be switched reliably.

  In the above embodiment, the case where the coil of the four-way valve 2 is energized (turned on) during the heating operation has been described. However, the present invention is applied to an air conditioner that energizes (turns on) the coil of the four-way valve 2 during the cooling operation. May be. In that case, the coil of the four-way valve 2 is deenergized (off) during the heating operation and during the stop. If the coil of the four-way valve 2 is immediately de-energized (off) due to the stop from the cooling operation, the four-way valve is switched from the cooling position to the heating position, and there is an abnormal noise in which the high pressure and low pressure of the refrigerant are reversed. Since this occurs, the coil of the four-way valve 2 is de-energized (turned off) after 3 minutes.

  In the above-described embodiment, the EEPROM 31 is used as the nonvolatile storage unit. However, the nonvolatile storage unit is not limited to this, and other types such as a ferroelectric memory and a RAM (random access memory) backed up by a power source are used. A non-volatile memory may be used.

FIG. 1 is a circuit diagram of a refrigerant circuit of an air conditioner according to an embodiment of the present invention. FIG. 2 is a flowchart for explaining the operation of the control unit of the air conditioner. FIG. 3 is a flowchart following FIG. FIG. 4 is a flowchart following FIG. FIG. 5 is a diagram showing a four-way valve position during heating operation.

DESCRIPTION OF SYMBOLS 1 ... Compressor 2 ... Four-way valve 3 ... Outdoor heat exchanger 4 ... Electric expansion valve 5 ... Indoor heat exchanger 6 ... Accumulator 7 ... Outdoor fan 8 ... Indoor fan 10 ... Outdoor unit 20 ... Indoor unit 30 ... Control part 31 ... EEPROM
TM1 ... Four-way valve operation guarantee timer TM2 ... Power off judgment timer

Claims (6)

A refrigerant circuit including a compressor (1) and a pilot-type four-way valve (2) for switching the flow of refrigerant discharged from the compressor (1);
A control unit (30) for controlling the four-way valve (2) and the compressor (1);
A non-volatile storage unit (31) for storing position information of the four-way valve (2) when the operation is stopped;
The control unit (30)
Before starting operation after turning on the power, the compressor (1) is operated at a predetermined frequency to ensure the differential pressure before and after the four-way valve (2) of the refrigerant circuit, and the four-way valve (2) is operated. It has a function to perform four-way valve operation guarantee control to be activated,
If the position information of the four-way valve (2) read from the nonvolatile storage unit (31) does not correspond to the next operation mode when the compressor (1) is started up after the power is turned off, The four-way valve (2) is switched to the position corresponding to the next operation mode by performing the road valve operation guarantee control, and the position information of the four-way valve (2) read from the nonvolatile storage unit (31) When corresponding to the following operation mode, the four-way valve operation assurance control is not performed,
Whether the position information of the four-way valve (2) to be written in the nonvolatile storage unit (31) is the cooling position during the cooling operation, the heating position during the heating operation, the cooling position, or the heating position. It is an indefinite position when it is not fixed, and position information of any one of the cooling position, the heating position, and the indefinite position is written in the nonvolatile storage unit (31),
The cooling position, the heating position, and the indefinite position are the operation mode according to either the heating cycle or the cooling cycle in the four-way valve that energizes the coil of the four-way valve during heating operation, and the compressor (1). Is operated at the predetermined frequency to activate the four-way valve (2), and is determined based on the state of the four-way valve operation assurance control.
When the operation mode is the cooling cycle or the heating cycle, the four-way valve operation guarantee control is operating or stopped during operation, the position information of the four-way valve is set to the indefinite position,
When the operation mode is a cooling cycle, the operation after the operation of the four-way valve operation guarantee control or the stop after the operation , the position information of the four-way valve is the cooling position,
After the operation of the four-way valve operation guarantee control when the operation mode is a heating cycle, the position information of the four-way valve is the heating position,
When the operation mode is a heating cycle, if the coil of the four-way valve is in an energized state within a certain period of time after the operation of the four-way valve operation guarantee control, the position information of the four-way valve is displayed . The heating position,
When the operation mode is a heating cycle, the air conditioner is characterized in that the position information of the four-way valve is set to the indefinite position after the predetermined time has elapsed since the stop after the operation of the four-way valve operation guarantee control. Machine. In the air conditioner according to claim 1,
At the time of shipment, the air conditioner is characterized in that position information indicating indefiniteness is stored in the nonvolatile storage unit (31) regardless of the position of the four-way valve (2). In the air conditioner according to claim 1 or 2 ,
The control unit (30) writes the current position information of the four-way valve (2) obtained based on the operating state during operation into the nonvolatile storage unit (31) when the operation is stopped. Air conditioner. In the air conditioner according to any one of claims 1 to 3 ,
The control unit (30)
By operating the compressor (1) at the predetermined frequency while energizing the coil of the four-way valve (2) during the heating operation, the four-way operation is performed so that the refrigerant flow in the refrigerant circuit becomes a heating cycle. While switching valve (2)
By operating the compressor (1) at the predetermined frequency without energizing the coil of the four-way valve (2) during the cooling operation, the four-way so that the refrigerant flow in the refrigerant circuit becomes a cooling cycle. An air conditioner characterized by switching the valve (2). In the air conditioner according to any one of claims 1 to 3 ,
The control unit (30)
By operating the compressor (1) at the predetermined frequency while energizing the coil of the four-way valve (2) during the cooling operation, the four-way so that the refrigerant flow in the refrigerant circuit becomes a cooling cycle. While switching valve (2)
By operating the compressor (1) at the predetermined frequency without energizing the coil of the four-way valve (2) during the heating operation, the four-way so that the refrigerant flow in the refrigerant circuit becomes a heating cycle. An air conditioner characterized by switching the valve (2). A refrigerant circuit in which refrigerant discharged from the compressor (1) circulates, a pilot-type four-way valve (2) for switching the refrigerant flow in the refrigerant circuit, the four-way valve (2), and the compressor (1 A control unit (30) for controlling the air conditioner, and a non-volatile storage unit (31) for storing the positional information of the four-way valve (2) when operation is stopped,
The position information of the four-way valve (2) read out from the nonvolatile storage unit (31) when the compressor (1) is started up after the power is turned off by the control unit (30) is the next operation mode. When the compressor (1) is operated at a predetermined frequency and the four-way valve (2) is operated, the four-way valve (2) is switched to a position corresponding to the next operation mode. While performing valve operation guarantee control,
Whether the position information of the four-way valve (2) to be written in the nonvolatile storage unit (31) is the cooling position during the cooling operation, the heating position during the heating operation, the cooling position, or the heating position. It is an indefinite position when it is not fixed, and position information of any one of the cooling position, the heating position, and the indefinite position is written in the nonvolatile storage unit (31),
The cooling position, the heating position, and the indefinite position are the operation mode according to either the heating cycle or the cooling cycle in the four-way valve that energizes the coil of the four-way valve during heating operation, and the compressor (1). Is operated at the predetermined frequency to activate the four-way valve (2), and is determined based on the state of the four-way valve operation assurance control.
When the operation mode is the cooling cycle or the heating cycle, the four-way valve operation guarantee control is operating or stopped during operation, the position information of the four-way valve is set to the indefinite position,
When the operation mode is a cooling cycle, the operation after the operation of the four-way valve operation guarantee control or the stop after the operation , the position information of the four-way valve is the cooling position,
After the operation of the four-way valve operation guarantee control when the operation mode is a heating cycle, the position information of the four-way valve is the heating position,
When the operation mode is a heating cycle, if the coil of the four-way valve is in an energized state within a certain period of time after the operation of the four-way valve operation guarantee control, the position information of the four-way valve is displayed . The heating position,
When the operation mode is a heating cycle, the air conditioner is characterized in that the position information of the four-way valve is set to the indefinite position after the predetermined time has elapsed since the stop after the operation of the four-way valve operation guarantee control. How to control the machine.

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