JP5622547B2 - Multi-room air conditioner - Google Patents

Description

  The present invention relates to control of a blower in a multi-room type air conditioner.

  An air conditioner circulates indoor air through a heat exchanger, converts it into conditioned air by heating, cooling, dehumidifying functions, and the like, and blows the air into the room to air-condition the room. In recent years, as the living environment deteriorates due to frequent hot days, it is not unusual to install one air conditioner in a room, and install outdoor units as the number of units installed per unit increases. Increasing number of cases where it is difficult to secure a place, and installing a multi-room type air conditioner as a solution to reduce the number of outdoor units.

  In such a heating operation of a plurality of indoor units connected to the same outdoor unit in a multi-room type air conditioner, when a thermostat off or stop indoor unit and a thermostat on indoor unit are mixed, In the case of an indoor unit that is thermostat-off due to the influence of the high-temperature refrigerant flowing in the heat exchanger when an operation method that prevents a shortage of refrigerant by flowing a small amount of refrigerant in the thermostat-off or stopped indoor unit is also adopted. Temperature tends to rise.

  If this influence reaches the suction temperature sensor provided in the suction air passage of the heat exchanger for room temperature detection, the detection temperature of the suction temperature sensor becomes higher than the suction temperature, which may hinder the adjustment of the room temperature. In order to prevent this, the blower is appropriately operated to send suction air around the suction temperature sensor to weaken the influence of the high-temperature refrigerant flowing in the heat exchanger.

  However, if there is too much air flow, the heat exchange between the intake air and the refrigerant is promoted, the liquid refrigerant that accumulates in the heat exchanger increases, and it is easy to fall short of the refrigerant. The amount of refrigerant flowing through the heat exchanger increases, the amount of heat exchange between the refrigerant and the intake air increases, and the room temperature tends to rise despite the thermostat off state, resulting in an overheating state.

  In addition, if the air flow rate is too small, the difference between the detection temperature of the suction temperature sensor and the room temperature becomes too large, resulting in the problem that good room temperature control becomes difficult. In order to solve this problem, various ideas have been devised for controlling the blower of the multi-room air conditioner. As this type of prior art, JP-A-2005-351551, JP-A-07-260237, JP-A-2001-336808, and JP-A-08-021668 are known.

  Patent Document 1 discloses a multi-type air conditioner that operates an indoor blower for a predetermined time, operates at a higher speed as the heat exchanger temperature is higher, or performs a low air volume pre-operation for a predetermined time, and then detects the indoor air temperature by the indoor temperature detection means of the indoor unit. Is detected, and a return determination from the heating standby state to the normal heating operation is performed based on the detection result. This describes a multi-type air conditioner that can prevent overheating or the like in which the indoor air temperature is higher than the set temperature, and keep the indoor air temperature at the set temperature.

  Patent Document 2 calculates a difference between a heat exchanger temperature and a predetermined value and a temporal change rate of the indoor heat exchanger temperature when a blower of one indoor unit is stopped by a room temperature adjustment function or the like. Fuzzy operation value of the blower is calculated according to the membership function, and the indoor blower is controlled so that the difference between this value and the predetermined value is larger in the positive direction and the temporal change rate is larger in the positive direction, so that the wind becomes smaller. It is controlled so that the wind is smaller or smaller than that. Thus, a control method and apparatus for an air conditioner capable of suppressing an increase in the temperature of a heat exchanger of an indoor unit in which an indoor blower is stopped and performing appropriate operation control in a multi-type air conditioner are described.

  In Patent Document 3, when the pipe temperature detected by the pipe temperature detecting means is lower than a predetermined temperature during the heating operation, the air volume of the indoor fan is set to a super-fine wind, and the wind direction provided rotatably in the indoor unit Control is performed so that the angle of the change blade is set to the closed position. As a result, by controlling the wind direction changing blade and the indoor fan according to the piping temperature, the temperature at the start of heating operation or when the thermostat is turned off is increased, and the feeling of cold air is reduced by reducing the air volume, thereby improving comfort. It describes an air conditioner.

  Patent Document 4 discloses a multi-type air conditioner in which an indoor unit that is not in operation has a predetermined temperature setting value that is detected by a temperature sensor that detects a pipe temperature or a temperature sensor that detects an in-machine temperature. If higher, the opening control means changes the intermittent blowing time ratio and intermittently blows without stopping the fan provided in the indoor unit, and changes the opening of the electric expansion valve in the closing direction. Therefore, an air conditioner that can prevent the occurrence of warm air from the indoor unit that is not in operation and the erroneous detection of the room temperature due to the temperature rise in the machine is described.

JP-A-2005-351551 JP 07-260237 A JP 2001-336808 A Japanese Patent Laid-Open No. 08-021668

  In blower control when the thermostat of a multi-room air conditioner is turned off, in addition to avoiding shortage of refrigerant, returning the thermostat at an appropriate timing, and suppressing overheating, these requirements are realized at low cost. There is a need to.

  In Patent Document 1, there is a description of changing the wind speed according to the temperature of the heat exchanger, but there is no description of the relationship with the wind speed during normal heating operation.

  In Patent Document 2, the rate of change of the temperature of the heat exchanger must be obtained, and the fan speed must be determined by performing fuzzy calculation according to the rate of change. Become.

  Patent Document 3 describes prevention of blowing out cold air, and there is no description about the influence of the heat exchanger temperature on the suction temperature sensor and how to avoid it.

  In Patent Document 4, in order to avoid overheating, in a state where the thermostat is off, the fan is stopped or intermittently operated when the heat exchanger temperature is high to reduce heat radiation to the room. As a result of such operation, There is no description about the accumulation of refrigerant.

  A problem to be solved by the present invention is a multi-room air conditioner capable of improving the detection accuracy of the intake air temperature and increasing the temperature adjustment accuracy of the indoor air while suppressing overheating by avoiding refrigerant shortage. Is to provide.

The problem to be solved by the present invention is a heating operation of a plurality of indoor units connected to the same outdoor unit, in a state where a thermostat-off indoor unit or a stopped indoor unit and a thermostat-on indoor unit coexist. in the multi-room air conditioner to flow even (small amount of) the refrigerant to the indoor unit of the indoor unit or stop thermostat off, in the heating operation of the plurality of indoor units, and an indoor unit of the indoor unit and the thermostat on the thermostat off there there is time to mix, when the temperature of the heat exchanger of the indoor unit of the thermostat off the first predetermined temperature (T1) above, manually selectable minimum wind speed or wind speed blower of the indoor unit of the thermostat-off If, operating at wind pattern composed of two or more wind speed including wind speed of less than manually selectable minimum wind speed, heating operation of the plurality of indoor units, the indoor unit and the thermostat on the stop When the indoor unit is mixed, the operation of the blower of the stopped indoor unit is stopped, and the temperature of the heat exchanger of the indoor unit that has started the operation is the first when the stopped indoor unit starts operating. Achieved by operating the blower of the indoor unit that has started operation for a predetermined time at a wind speed equal to or higher than the set wind speed even when the thermostat is off, when the temperature is equal to or higher than the third predetermined temperature (T3) higher than the predetermined temperature (T1). Is done.

  The multi-room air conditioner according to claim 2 is the multi-room air conditioner according to claim 1, wherein the wind speed pattern includes repetition of a basic wind speed pattern in which the two or more wind speeds are combined in time series. .

  The multi-room air conditioner according to claim 3 is the multi-room air conditioner according to claim 1, wherein the heat exchanger temperature of the thermostat-off indoor unit is equal to or higher than a first predetermined temperature (T1). Is operated with a wind speed pattern constituted by three or more wind speeds below the set wind speed without stopping.

  The multi-room air conditioner according to claim 4 is the multi-room air conditioner according to claim 3, wherein the wind speed pattern includes repetition of a basic wind speed pattern in which the three or more wind speeds are combined in time series. .

  The multi-room air conditioner according to claim 5 is the multi-room air conditioner according to claim 2 or 4, wherein the operation time of the ultra-low wind speed in the repetitive operation is 0. 4 to 0.7.

  The multi-room air conditioner according to claim 6 is the multi-room air conditioner according to claim 1 or 3, wherein all of the indoor units in operation are thermostat-off in the heating operation of the plurality of indoor units. When the temperature of the heat exchanger of the thermostat-off indoor unit is equal to or higher than the first predetermined temperature (T1), the operating wind speed of the blower is set to be equal to or lower than the set wind speed. It is a monotonous decrease in wind speed.

  According to the first aspect of the present invention, there is provided a multi-room air conditioner that avoids refrigerant shortage and suppresses overheating while improving the detection accuracy of the intake air temperature and increasing the temperature adjustment accuracy of the indoor air. can do.

  According to the second aspect, overheating is reliably suppressed by avoiding shortage of refrigerant, and the temperature of the room is reliably adjusted.

  According to the third aspect, overheating is strongly suppressed, and the uncomfortable feeling of the occupants is reduced.

  According to the fourth aspect, overheating is strongly and surely suppressed, the uncomfortable feeling of the occupants is reduced, and the temperature of the room is reliably adjusted.

  According to the fifth aspect, energy is saved while maintaining the thermal sensation of the occupants.

  According to the sixth aspect, energy is saved while avoiding refrigerant shortage and suppressing overheating.

The perspective view of the air conditioner of an Example. Example 1 of the indoor unit of the air conditioner of FIG. Example 2 of the indoor unit of the air conditioner of FIG. Example 1 of the refrigeration cycle of the air conditioner of the example. Example 2 of the refrigerating cycle of the air conditioner of an Example. Air conditioner operation control flow main part. Wind speed setting control flow main part. The main part of the flow control flow during medium heat temperature. During compressor operation Thermostat on → off Wind speed control flow main part. When the thermostat is off Compressor is stopped → Operation Wind speed control flow. When the thermostat is off Compressor is running → Stop Wind speed control flow. During compressor operation When thermostat is off Initial wind speed control flow. Compressor is running. When thermostat is off. During compressor operation Thermostat on → off Wind speed control time chart. When the thermostat is off Compressor is running → Stop Wind speed control time chart. Thermostat ON → OFF Compressor operation → Stop Wind speed control time chart.

  First, the heating operation in this specification is a state in which the air conditioner is operated in the heating operation mode, the operation of operating the compressor in the heat pump cycle, and heating the room, and the temperature or humidity control device. The operation including the low-capacity operation or the interruption of the compressor operation is referred to.

  Details of the present invention will be described below. First, the overall configuration will be described with reference to FIGS. FIG. 1 is a perspective view of an air conditioner according to an embodiment. FIG. 2 is an example 1 of the indoor unit of the air conditioner of FIG. FIG. 3 is an example 2 of the indoor unit of the air conditioner of FIG.

  In FIG. 1, a multi-room air conditioner generally indicated by reference numeral 1 connects indoor units 2 a, 2 b, 2 c and an outdoor unit 6 with a connection pipe 8 to air condition the room. FIG. 1 shows an example of a multi-room air conditioner according to the present invention, which shows a combination of wall-mounted indoor units 2a, 2b and a ceiling-embedded indoor unit 2c as indoor units.

  In the following description, the same function parts for the indoor units 2a, 2b, and 2c are denoted by the same reference numerals, and when distinguished by the indoor units, the same reference numerals are followed by a, b. Note that a, b,... After the reference numerals are omitted for common explanations that do not distinguish between indoor units.

  The indoor units 2a, 2b, and 2c have an indoor heat exchanger 33 placed at the center of the casing body 21, a cross-flow fan blower 311 is disposed downstream of the air flow of the heat exchanger 33, and a dew tray 35 and the like are installed. The decorative panel 25 is attached so as to face the air-conditioned space of the housing body 21. The decorative panel 25 is provided with an air inlet 27 for sucking in indoor air and an air outlet 29 for blowing out air in which temperature and humidity are harmonized.

  There is a filter 231 for removing dust from the circulating air between the air inlet 27 and the indoor heat exchanger 33, and an automatic cleaning device 240 is provided on the suction surface side so that the filter 231 is automatically turned on when the air conditioner is stopped. Clean and keep the filter clean and restore air blowing performance so that energy-saving performance is not reduced.

  The blown airflow from the blower 311 is caused to flow into a blowout air passage 290 having a width substantially equal to the length of the blower 311, and the vertical airflow direction plate 291 disposed in the blowout port 29 deflects the vertical direction of the airflow and blows it into the room. It can be done.

  Basic internal structures such as a blower 311, an indoor heat exchanger 33, and a dew tray 35 are attached to the housing body 21. These basic internal structures are included in a casing 20 including a casing main body 21 and a decorative panel 25 to constitute the indoor unit 2. In addition, the decorative panel 25 is provided with a display unit that displays the driving situation and a transmission / reception unit 396 that exchanges infrared signals with a separate remote controller 5.

  The suction panel 251 is configured to be rotated by driving the opening / closing arm 83 with the arm driving device 81 using a rotation shaft provided on the decorative panel 25 as a fulcrum, and to open the air suction port 27 during operation of the air conditioner. ing. Thereby, indoor air is sucked into the indoor unit 2 from the air suction port 27 during operation.

  An air outlet 29 formed on the lower surface of the decorative panel 25 communicates with the rear outlet air passage 290. The up-and-down air direction plate 291 substantially conceals the blowing air path 290 in the closed state. The vertical wind direction plate 291 is pivoted at a required angle when the air conditioner is operated by a drive motor in response to an instruction from the remote controller 5 with pivot shafts provided at both ends as fulcrums. Open and hold in that state.

  The indoor unit 2 includes a control unit 10 (not shown) inside, and the control unit 10 is provided with a microcomputer. The microcomputer receives signals from various sensors such as an indoor temperature sensor and an indoor humidity sensor, and transmits and receives an infrared signal to and from the remote controller 5 via the transmission / reception unit 396. Based on these signals, the microcomputer controls the indoor blower 311, the suction panel drive motor, the up / down wind direction drive motor, and the like, and controls communication with the outdoor unit 6 to control the indoor unit 2 in an integrated manner.

  When the operation of the air conditioner is stopped, as shown by broken lines in FIGS. 2 and 3, the suction panel 251 is controlled to close the air suction port 27, and the vertical wind direction plate 291 is controlled to close the air blowout port 29. The By giving an instruction from the remote controller 5, the up-and-down air direction plate 291 can be periodically swung during the operation of the air conditioner, and the blown air can be periodically sent over a wide range in the room.

  The dew receiving tray 35 is disposed below the lower end portion of the indoor heat exchanger 33 and is provided to receive condensed water condensed on the indoor heat exchanger 33 during cooling operation or dehumidifying operation. The condensed water received and collected is discharged to the outside through the drain pipe 37.

  Next, the refrigeration cycle of the multi-room air conditioner will be briefly described with reference to FIGS. FIG. 4 is Example 1 of the refrigeration cycle of the air conditioner of the embodiment. FIG. 5 is a second example of the refrigeration cycle of the air conditioner of the embodiment.

  FIG. 4 shows an example in which two indoor units are connected to a single outdoor unit. Reference numeral 70 generally indicates a refrigeration cycle of a multi-room air conditioner for air conditioning.

  In the figure, 75 is a compressor, 72 is a refrigerant flow path switching valve, 73 is an outdoor heat exchanger, 74 is a cooling / heating throttle device, 78 is a narrow pipe connection valve, 33 is an indoor heat exchanger, 79 is a thick pipe connection valve, Reference numeral 171 denotes a suction temperature sensor.

  The refrigerant compressed by the compressor 75 is switched in the flow path by the refrigerant flow switching valve 72. During heating, the large pipe connection valve 79, the indoor heat exchanger 33, the narrow pipe connection valve 78, the cooling / heating throttle device 74, the outdoor heat. It flows in the order of the exchanger 73 and the refrigerant | coolant flow path switching valve 72, returns to the compressor 75, and heats a room | chamber interior. During cooling, the flow path is switched by the refrigerant flow path switching valve 72, and the refrigerant flows in the opposite direction to that during heating to cool the room. Further, the indoor heat exchanger 33 can be divided into two and connected in series, and a dehumidifying operation can be performed by interposing a dehumidifying throttle device (not shown) therebetween.

  The operation of this multi-room air conditioner will be described with heating as an example.

  When operating this multi-room air conditioner, first, a heating operation instruction is given by a remote controller 5a of one indoor unit, for example, the indoor unit 2a. The instruction from the remote controller 5a is transmitted to the transmission / reception unit 396a of the indoor unit 2a by infrared rays and reaches the control unit 10a of the indoor unit 2a. The control unit 10a is configured based on the setting of the indoor temperature and the temperature information from the suction temperature sensor 171a. The necessary refrigeration capacity is calculated, and the compression function required for the outdoor unit 6 is transmitted as the required compression function.

  The outdoor unit 6 that has received the transmission of the required compression function force takes into account the required compression function force from other indoor units by an outdoor unit control unit (not shown), the rotational speed of the compressor 75, the outdoor blower (not shown), air conditioning The throttle amount of the expansion device 74a is controlled to respond to the request of the indoor unit 2a, and the requested room is heated.

  When the requested room is warmed and it is determined that the room temperature has reached the set temperature based on the temperature information from the suction temperature sensor 171a of the indoor unit 2a, the control unit 10a determines that the temperature adjustment device (hereinafter referred to as a thermostat for short). ) Is activated, the required compression function force is set to zero and transmitted to the outdoor unit 6.

  The outdoor unit 6 that has received transmission of zero required compression function force from the indoor unit 2a stops the operation of the compressor when there is no required compression function force from other indoor units. Further, when there is a required compression function force from another indoor unit, the rotational speed of the compressor 75 and the outdoor blower (not shown) are decelerated so as to meet the corresponding capacity.

  At this time, when the cooling / heating throttle device 74a for the indoor unit 2a having the required compression function force zero is completely shut off, the high-pressure refrigerant is stored in a liquid state in the refrigerant circuit of the indoor unit 2a, and the refrigeration cycle falls into a refrigerant shortage state. In order to prevent this, avoiding completely shutting off the cooling / heating throttle device 74a for the indoor unit 2a, slightly opening it so that a little refrigerant flows through the refrigerant circuit of the indoor unit 2a, and liquid refrigerant accumulates in this circuit. Need to be prevented.

  For this reason, since a high temperature refrigerant | coolant flows a little in the heat exchanger 33a of the indoor unit 2a, the indoor air blower 311 is stopped and the indoor heat exchange is suppressed as much as possible. However, when the indoor blower 311 is completely stopped, depending on the structure of the indoor unit, the interior of the indoor unit is warmed by the high-temperature refrigerant flowing through the heat exchanger 33a, and the temperature of the suction temperature sensor 171a provided inside the indoor unit is There is a risk that the thermostat will not operate normally due to a deviation from the room temperature. For this reason, the control described later is employed to avoid this.

  FIG. 5 shows an example in which four indoor units are connected to one outdoor unit, and reference numeral 70 generally indicates a refrigeration cycle of a multi-room air conditioner for cooling and heating.

  Also in this case, the indoor unit is operated in the same manner as the example in which two indoor units are connected, and the relationship between the required compression function force of the indoor unit that the outdoor unit intends to heat and the required compression function force of the other indoor units is set. Based on this, it is operated in the same manner as described above.

  As described above, in the case of heating, the room that is operated as described above and has been requested to be heated is heated with an appropriate heating capacity.

  Furthermore, in the case of cooling or dehumidification, the outdoor unit 6 is in a refrigeration cycle opposite to heating, based on the relationship between the required compression function of the indoor unit to be cooled or dehumidified and the required compression function of other indoor units. The operation is the same as described above.

  The control when the thermostat is operated shuts off the cooling / heating throttle device 74 for the indoor unit. This is because, unlike heating, the indoor heat exchanger 33 is kept at a low pressure, the refrigerant in the interrupted refrigerant circuit is maintained in a gaseous state, and the refrigeration cycle is not likely to run out of refrigerant. Thereby, there is no problem even if the operation of the indoor blower 311 is continued even when the thermostat is operated.

  Next, control of a blower suitable for a multi-room air conditioner will be described with reference to FIGS.

In this specification, description of normal operation control of the multi-room air conditioner will be omitted, and description will be given with emphasis on control of the blower of the multi-room air conditioner. In order to prevent confusion and make it easy to understand, the following five cases (A) to (E) will be described step by step.
(A) Thermostat on at the start of heating operation, then thermostat off, medium heat exchange temperature, compressor continues on, then compressor off, then thermostat on (B) Thermostat on at the start of heating operation, then thermostat off, medium heat exchange Temperature, compressor off, compressor on, then thermostat on (C) thermostat on when heating operation started, then thermostat off, low heat exchange temperature, then thermostat on (D) thermostat off when heating operation started, high heat exchange temperature, Then thermostat on (E) Heating operation starts thermostat off, medium / low heat exchange temperature, then thermostat on

≪Blower control≫
(A) Thermostat on at the start of heating operation, then thermostat off, medium heat exchange temperature, compressor continues to be on, then compressor off, then thermostat on First, control for thermostat on at the start of heating operation and then thermostat off This will be described with reference to FIGS.

  First, operation control of the air conditioner will be described with reference to FIG. FIG. 6 shows the main part of the air conditioner operation control flow.

  First, the indoor unit is turned on in step S100 of FIG. 6, the initial setting is performed in step S101, the remote control operation is checked in step S105, and if the operation is correct, the operation mode change is checked in step S110. If the operation mode is changed, the operation mode is set in step S111, and if the change is not stopped in step S120, the operation mode is checked in step S125.

  If the operation mode is the heating operation mode, in step S126, the thermostat history flag indicating the history of thermostat on from the start of operation is turned off, and the compressor history flag that is turned off from the compressor stop until the predetermined time after the compressor operation is turned on is turned on. , Reset the heat exchange timer that measures the predetermined time to forcibly operate the blower, perform the initial settings necessary for the operation mode set in step S127, and in step S130, set the operation details such as the set room temperature, wind speed and wind direction plate position In step S131, data such as various sensors and timers arranged in the aircraft is acquired. If the heating operation mode is set in step S135, the wind speed is set in step S136, and the heating operation is started in step S137.

  Next, the wind speed setting control of step S136 is demonstrated using FIG. 6, FIG. FIG. 7 shows the main part of the wind speed setting control flow.

  From step S136 in FIG. 6 to step S200 in FIG. 7, the thermostat history flag is checked in step S205. Since the thermostat history flag is turned off in step S126 in FIG. 6, the process proceeds to step S215, and the thermostat is checked. In this case, since it is assumed that the thermostat is turned on immediately after the start of heating, the process proceeds to step S247, and various timers used for control when the thermostat is turned off are reset.

  Next, in step S250, the thermostat history flag is turned on, the initial 3 minute flag is turned on, the compressor history flag is turned on, and in step S251, the wind speed is set to the control wind speed when the thermostat is turned on, and step S137 in FIG. 6 is performed via step S280. Return to.

  In step S137, the heating operation is performed, and the process returns to step S105. If the remote control is operated, the operation details are reset in steps S110, S115, and S130 according to the instruction, and the process proceeds to step S131. If not, the process proceeds directly to step S131, proceeds from step S135 to step S136, and enters the wind speed setting control again.

  From step S136, the process jumps to step S205 in FIG. 7 to check the thermostat history flag. Unlike the previous time, the thermostat history flag is turned on in step S250. Therefore, the process proceeds to step S210, where it is checked whether the heat exchange timer has started. In this case, the heat exchange timer start step passes. Since it is not, the process proceeds to step S225.

  In step S225, the state of the thermostat is checked. Since the thermostat is turned on based on the premise, the process proceeds to step S247, and in the same manner as described above, steps S250, S251, S280, S137, S105, S131, S135, S136, and so on. The control of S205, S210, S225, S247 is repeated. As described above, the indoor unit repeats the control of the thermostat on state until the thermostat is turned off in step S225.

  Subsequently, the thermostat is switched from on to off, the temperature of the heat exchanger is medium heat exchange temperature, the compressor continues to be turned on, the compressor is turned off, and the control from the compressor to the thermostat is subsequently turned on. 15 will be described.

  If the thermostat state is changed to OFF in step S225 of FIG. 7, the thermostat history flag is checked in step S230. Since the thermostat history flag remains on, the process proceeds to step S235, where the heat exchange temperature is the medium heat exchange temperature. It is checked whether the state is equal to or higher than T1. Since the heat exchanger temperature is equal to or higher than T1 according to the premise, the process proceeds to step S242 to enter the air speed control during the intermediate heat exchange temperature.

  Next, the air speed control at the time of intermediate heat temperature in step S242 will be described with reference to FIG. FIG. 8 shows the main part of the wind speed control flow during the intermediate heat exchange temperature.

  From step S242 in FIG. 7 to step S300 in FIG. 8, it is checked in step S305 whether or not the compressor is in operation. Based on the premise, since the compressor continues to operate, the process proceeds to step S310. Check the history flag. Since the compressor history flag is turned on in step S250, the compressor is operating in step S311. The thermostat is turned on and turned off.

  Next, the thermostat ON → OFF wind speed control during compressor operation in step S311 will be described with reference to FIG. Fig. 9 shows the main part of the flow control flow of the thermostat when the compressor is operating.

  From step S311, the process jumps to step S400 in FIG. 9, and the state of the initial 3-minute flag is checked in step S405. In this case, since the initial 3-minute flag is turned on in step S250, the process proceeds to step S406 and the compressor is operated. Medium When the thermostat is off Initial wind speed control starts.

  Next, the initial wind speed control during the operation of the compressor during the thermostat off in step S406 will be described with reference to FIGS. 6 to 9, FIG. 12, and FIG. FIG. 12 shows the main part of the initial wind speed control flow when the compressor is in operation and the thermostat is off. FIG. 14 is a time chart of the wind speed control during operation of the compressor.

  Step S406 jumps to step S700 in FIG. 12, and it is checked in step S705 whether the 3m timer has started. In this case, since the 3m timer has not started, the 3m timer and the ON light wind timer are started in step S706. In step S710, the 3m timer is checked for time-up. Since the time has not yet been reached, the process proceeds to step S715.

  This 3 m timer is a time provided for avoiding an excessive change in the operating state from when the wind speed changes until the temperature detected by the suction temperature sensor is stabilized, and in this example, it is set to 3 minutes.

  In step S715, the time of the ON light wind timer is checked. If the time has not yet timed up, if the wind speed set by the user in steps S720 and S721 is automatic, strong wind, weak wind, or light wind, the wind speed is set to light wind. If the wind speed set by the user is “quiet”, which is the lowest wind speed that can be set, “quiet” is set in step S722.

  This ON Breeze Timer is a time provided to reduce the uncomfortable feeling given to the occupants by temporarily changing the wind speed from the set wind speed to the super wind with the thermostat turned off. Then it was 15 seconds.

  If the ON light wind timer has expired in step S715, in step S716, the super wind is set to be lower than the lowest wind speed that can be set by the user. After the setting of the wind speed described above, the process returns to step S480 in FIG. 9 via step S780, further returns to step S280 in FIG. 7 via step S380 in FIG. 8, and returns to step S137 in FIG. , Heating operation.

  In the next control cycle, since the 3m timer has already been started in step S705 in FIG. 12, the process proceeds directly to step S710, and the same control as described above is performed. This state is the time of the 3m timer in step S710 in FIG. Continue until up.

  As described above, when the compressor is operating even when the thermostat is turned off, the wind speed is set with the upper wind speed as the slight wind from the time when the thermostat is turned off until the ON fine wind timer expires as shown in the time chart of FIG. From the time up of the ON light wind timer to the time up of the 3 m timer, the wind speed of the super light wind is set.

  When the 3m timer expires in step S710 of FIG. 12, the initial 3-minute flag is turned off in step S711, and the compressor is operating in step S407 from the check of the initial 3-minute flag in step S405 of FIG. 9 in the next control cycle. When the thermostat is off, repeats wind speed control.

  Next, the repetitive wind speed control during the operation of the compressor in step S407 when the thermostat is off will be described with reference to FIG. 6 to FIG. 9, FIG. FIG. 13 shows the main part of the repeated wind speed control flow when the compressor is in operation and the thermostat is off.

  The process jumps from step S407 to step S800 in FIG. 13, and it is checked in step S805 whether the output timer has started. In this case, since the output timer has not started, the output timer is started in step S806, and step S810. In step S815, the time-up of the output timer is checked. Since the time is not yet up, the process proceeds to step S815.

  This output timer is set to measure the time to operate at or above the minimum wind speed when controlling the wind speed in multiple stages with the thermostat turned off. The time required for the difference between the detected temperature of the suction temperature sensor and the room temperature to fall within the allowable range, and the time required to restore the loss of uniformity of the temperature distribution in the room while the thermostat is off. It is determined by the value and is approximately 2 to 5 minutes. In the example, it was 3 minutes.

  If the wind speed set by the user in steps S815 and S816 is automatic, strong wind, or weak wind, the wind speed is set to low wind, and if the wind speed set by the user is “low” or “quiet” which is the lowest wind speed that can be set. In step S817, the same breeze as the wind speed set by the user or “quiet” is set. After the setting of the wind speed described above, the process returns to step S480 in FIG. 9 via step S880, further returns to step S280 in FIG. 7 via step S380 in FIG. 8, and returns to step S137 in FIG. , Heating operation.

  In the next control cycle, since the output timer has already been started in step S805 in FIG. 13, the process directly proceeds to step S810 and the same control as described above is performed. This state is the time of the output timer in step S810 in FIG. Continue until up.

  When the output timer expires in step S810 in FIG. 13, it is checked in step S820 whether or not the 30s timer has started. In this case, the 30s timer has not been started, so in step S821, the 30s timer is started. In step S825, the time up of the 30s timer is checked. Since the time has not yet been up, the process proceeds to step S826.

  This 30s timer has the same purpose as the above-mentioned ON light wind timer, and is provided to reduce the uncomfortable feeling given to the occupants by changing the wind speed from the wind speed above the minimum wind speed to the super wind. Time, which was 30 seconds in the example.

  In step S826, the lowest wind speed that can be set by the user is set to “quiet”, and the heating operation is performed following the same process described above.

  In the next control cycle, since the 30s timer has already been started in step S820 in FIG. 13, the process proceeds directly to step S825 and the same control as described above is performed. This state is the time of the 30s timer in step S825 in FIG. Continue until up.

  When the 30s timer expires in step S825 in FIG. 13, it is checked in step S830 whether or not the super-breeze timer has started. In this case, since the super-breeze timer has not been started, the super-breeze timer is started in step S831. In step S835, the super-wind timer is checked for time-up. Since the time has not yet been reached, the process proceeds to step S837 and the wind speed is set to super-wind.

  This super-breeze timer is set to measure the time to operate at ultra-low wind speeds when the thermostat is turned off and controlled by changing the wind speed to multiple stages. This is the time required to return the refrigerant accumulated in the heat exchanger to the outdoor unit, and good results can be obtained by setting the repetition interval to 0.4 to 0.7. In the example, the repetition interval was 0.42 times 2 minutes 30 seconds.

  After setting the wind speed described above, the heating operation is performed following the same process described above.

  In the next control cycle, since the super-breeze timer has already been started in step S830 in FIG. 13, the process proceeds directly to step S835 and the same control as described above is performed, and this state is set in step S835 in FIG. It continues until the time is up.

  When the super-breeze timer expires in step S835, the output timer, 30s timer, and super-breeze timer are reset in step S836, and the wind speed maintains the super-breeze. Since the above timer has been reset, each timer starts again in steps S805, S820, and S830 in the subsequent control cycles, and the wind speed is changed over time to the upper wind speed at low wind, "quiet", and ultra-fine wind. The control is repeated.

  In this way, when the compressor is operating even when the thermostat is turned off, as shown in the repetition interval of the time chart of FIG. 14, following the initial wind speed control described above until the output timer expires, The wind speed is set with a low upper wind speed, and from the time up of the output timer to the time up of the 30s timer, the "quiet" wind speed is set up, from the time up of the 30s timer to the time up of the ultra-fine wind timer The wind speed is set for the super-fine wind.

  Here, the sum of the times of the output timer, the 30s timer, and the super-breeze timer is the repetition interval t1, and in the embodiment, 3 minutes + 30 seconds + 2 minutes 30 seconds = 6 minutes.

  This repetition continues until the compressor is turned off in step S305 in FIG. 8 or until the thermostat is turned on in step S225 in FIG. 7. When the compressor is turned off in step S305, the compressor is operating in the thermostat off in step S313. → Stop Move to wind speed control.

  Thus, the multi-room air conditioner of the embodiment is a state in which a thermostat off or stop indoor unit and a thermostat on indoor unit coexist in the heating operation of a plurality of indoor units connected to the same outdoor unit At this time, an operation method is adopted in which a small amount of refrigerant is allowed to flow through the indoor units that are turned off or stopped to prevent shortage of refrigerants. When the heat exchanger temperature of the thermostat-off indoor unit is equal to or higher than the first predetermined temperature (T1), the wind speed is higher than the lowest wind speed at which the blower can be manually selected and less than the lowest wind speed at which manual selection is possible. The vehicle is operated in a wind speed pattern composed of two or more wind speeds including the wind speed.

  As a result, if the temperature of the heat exchanger of the indoor unit that is thermostatted off is too high and the effect on the suction temperature sensor is too great, operate the blower and send room air around the suction temperature sensor to Make sure that the temperature detected by the temperature sensor does not deviate significantly from the room temperature.

  At this time, the wind speed is divided into two or more stages, and at least one of the stages is set to a wind speed higher than the minimum wind speed that can be set by the user with a remote controller or the like. The minimum wind speed that can be set by the user with the remote control is required to allow the air conditioner to operate without any problems at that wind speed, and the thermostat operation and return characteristics do not at least become a practical obstacle. It is stipulated in.

  In this way, since the wind speed pattern of the air blow when the thermostat is off includes the time when operating at a wind speed higher than the minimum wind speed, the thermostat can be operated and restored without any problem by operating at this wind speed for the required time. The thermostat will return too slowly and there is no risk of overheating.

  At this time, at least one stage of the wind speed is set to a wind speed lower than the minimum wind speed that the user can set with the remote controller. As a result, the amount of heat exchange between the refrigerant and the intake air is reduced, there is no risk of refrigerant shortage, and the intake air always flows around the intake temperature sensor at a low speed. Can be reduced.

  In addition, as described above, suction air always flows around the suction temperature sensor at a low speed, so the suction temperature sensor is exposed to the suction air including the surroundings, so it operates at a wind speed higher than the above-mentioned minimum wind speed. In addition, the time required for determining whether or not the intake air temperature has reached the return temperature of the thermostat can be shortened, and the amount of heat exchange is reduced accordingly, and overheating is suppressed.

  For this reason, it is possible to provide a multi-room air conditioner that increases the accuracy of detecting the intake air temperature and increases the temperature adjustment accuracy of the indoor air while avoiding the shortage of refrigerant and suppressing overheating.

  In the multi-room air conditioner of the embodiment, the wind speed pattern includes repetition of a basic wind speed pattern in which the two or more wind speeds are combined in time series.

  As a result, the temperature at the outlet of the indoor heat exchanger is heated according to the wind speed above the minimum wind speed at which the thermostat is reliably operated and restored, and the opening of the expansion valve that is slightly opened to suppress the accumulation of refrigerant. Since it is operated repeatedly in combination with an ultra-low wind speed that is set to be higher than during operation, the thermostat reliably recovers when it is operated at a wind speed higher than the minimum wind speed when the suction temperature falls, and overheating does not occur.

  In addition, when operating at a wind speed higher than the minimum wind speed, a small amount of refrigerant accumulates, but since this accumulation is also eliminated during ultra-low wind speed operation, a slight accumulation of refrigerant and elimination of the accumulation are repeated. In addition, accumulation of a large amount of refrigerant that interferes with the operation of the refrigeration cycle is avoided. In the examples, the above ultra-low wind speed was set to 1/3 or more of the minimum wind speed and 1/2 or less of the rated wind speed, and good results were obtained.

  For this reason, it is possible to provide a multi-room air conditioner that avoids refrigerant shortage, reliably suppresses overheating, and reliably adjusts the temperature of the room.

  The multi-room air conditioner of the embodiment has three or more stages below the set wind speed without stopping the blower when the heat exchanger temperature of the thermostat-off indoor unit is equal to or higher than the first predetermined temperature (T1). Driving with a wind speed pattern composed of

  In general, when changing the rotational speed of the blower, when the vehicle is decelerated, the load serves as a brake, so that the vehicle can be decelerated quickly. However, when increasing the speed, it is necessary to output a larger force against the load, so it is necessary to increase the speed slowly over time according to the current limit of the driver that drives the fan and the current capacity of the power supply circuit. There is.

  In the multi-room air conditioner of the embodiment, since the operation at the set wind speed higher than the minimum wind speed is entered, the operation temperature at the set wind speed at which the detected temperature of the suction temperature sensor approaches the suction temperature quickly and overheating tends to occur. Shortens and less likely to overheat. In addition, it is easy to change the speed of the blower from the set wind speed to the ultra-low wind speed as described above, but the change in the wind speed is too rapid, which may make the user feel uncomfortable and disturb the calmness of the room. is there.

  For this reason, when decelerating from the set wind speed to the ultra-low wind speed, a time for operating at the intermediate wind speed is provided in the middle so that the wind speed does not change suddenly, and the user does not feel uncomfortable. On the other hand, when increasing the speed, as described above, by slowly accelerating according to the current capacity of the power source and the current limit of the driver, abrupt changes in the wind speed are avoided, and the occupant's uncomfortable feeling is lightened to perform gentle air conditioning be able to.

  For this reason, it is possible to provide a multi-room air conditioner that strongly suppresses overheating and reduces the uncomfortable feeling of occupants.

  In the multi-room air conditioner of the embodiment, the wind speed pattern includes repetition of a basic wind speed pattern in which the three or more wind speeds are combined in time series.

  As a result, the operation and return of the thermostat are performed more reliably, and overheating is not performed, and accumulation of a large amount of refrigerant that interferes with the operation of the refrigeration cycle is avoided.

  For this reason, it is possible to provide a multi-room air conditioner that strongly suppresses overheating, reduces the uncomfortable feeling of the occupants, and reliably adjusts the temperature of the room.

  In the multi-room air conditioner of the embodiment, the operation time of the ultra low wind speed in the repeated operation is 0.4 to 0.7 of the interval of the repeated operation.

  As a result, the refrigerant that has accumulated in the heat exchanger when operating at the wind speed of the upper limit weak wind during repeated operation can be returned to the outdoor unit, and refrigerant shortage can be improved. When the operating time of ultra-low wind speed is less than 0.4 of the interval between repeated operations, the ability to return the refrigerant accumulated in the heat exchanger to the outdoor unit is insufficient, and the refrigerant that gradually accumulates in the heat exchanger every time it is repeated The risk of falling into a refrigerant shortage eventually increases.

  In addition, if the operating time of ultra-low wind speed exceeds 0.7, which is the interval between repeated operations, the difference between the detection temperature of the suction temperature sensor and room temperature increases due to the effect of the heat exchanger temperature, and within the upper limit weak wind operating time. The difference between the suction temperature sensor and the room temperature does not fall within the allowable range, the delay in thermostat on increases, the fluctuation of the room temperature increases, and the temperature distribution in the room during ultra low wind speed operation is not uniform. It becomes worse and the uniformity cannot be recovered within the upper limit low wind operation time, and the air conditioning quality deteriorates.

  Therefore, it is possible to provide a multi-room air conditioner that saves energy while maintaining the thermal sensation of the occupants.

  Next, when the thermostat is turned off in step S313, the compressor is operating and stopped. The wind speed control will be described with reference to FIGS. Fig. 11 shows the main part of the flow control flow when the thermostat is off. FIG. 15 is a time chart of the wind speed control when the thermostat is off and the compressor is operating.

  When the compressor is turned off in step S305 in FIG. 8, when the thermostat is turned off in step S313, the compressor is operating → stopped. The flow proceeds to step S600 from step S313 to step S600 in FIG. 11, and the OF light wind timer is started in step S605. In this case, since the OF light wind timer has not been started, the OF light wind timer is started in step S606, and the compressor history flag is turned off in step S611.

  This OF breeze timer has the same purpose as the above-mentioned ON breeze timer, and changes the air velocity from the upper limit weak wind speed to the super breeze during the repetitive wind speed control described above, and gives it to the occupants as an intermediate wind speed. This time is set to reduce the sense of incongruity, and is set to 15 seconds in the embodiment.

  In step S615, the time of the OF light wind timer is checked. If the time has not yet timed up, if the wind speed set by the user in steps S620 and S621 is automatic, strong wind, weak wind, or light wind, the wind speed is set to light wind. If the wind speed set by the user is “quiet”, which is the lowest wind speed that can be set, “quiet” is set in step S622.

  If the OF light wind timer has expired in step S615, the super wind is set at a wind speed lower than the lowest wind speed that can be set by the user in step S616. After the setting of the wind speed described above, the process returns to step S380 in FIG. 8 through step S680, further returns to step 280 in FIG. 7, and further returns to step S137 in FIG. 6 to perform the heating operation.

  In the next control cycle, since the OF light wind timer has already been started in step S605 in FIG. 11, the process proceeds directly to step S611 and the same control as described above is performed. This state is the OF light wind timer in step S615 in FIG. It continues until the time is up.

  As described above, when the thermostat is off and the compressor is changed from being operated to being stopped, as shown in the time chart of FIG. 15, the upper wind speed is set to be a slight wind from the compressor stop to the time up of the OF light wind timer. The wind speed is set, and the wind speed setting of the super-fine wind is performed from the time up of the OF light wind timer.

  This state continues until the thermostat is turned on in step S225 of FIG. 7, and when the thermostat is turned on, the above-described thermostat on control starting from step S247 is repeated.

  Thus, in the multi-room air conditioner of the embodiment, when all the indoor units in operation are in a thermostat-off state in the heating operation of the plurality of indoor units, the heat exchanger temperature of the thermostat-off indoor unit When the temperature is equal to or higher than the first predetermined temperature (T1), the operating wind speed of the blower is set to be equal to or lower than the set wind speed and is monotonously decreased with time to an ultra-low wind speed lower than the lowest wind speed that can be manually selected.

  Thereby, since the compressor is stopped, the high-temperature refrigerant does not flow in the heat exchanger, the heat in the machine is gradually dissipated, and the heat influence from the heat exchanger on the suction temperature sensor is also weakened. For this reason, the difference between the temperature detected by the suction temperature sensor and the temperature of the suction air is reduced, and even if the wind speed is gradually reduced, there is no problem and energy saving of the blower can be measured. It is also possible to prevent sudden changes in wind speed.

For this reason, it is possible to provide a multi-room air conditioner that saves energy while avoiding refrigerant shortage and suppressing overheating.
(B) Thermostat on at the start of heating operation, then thermostat off, medium heat exchange temperature, compressor also off, then compressor on, then thermostat on Next, thermostat on heating operation start, then thermostat off, medium heat exchange The control when the compressor is turned off, the compressor is turned on, and then the thermostat is turned on will be described with reference to FIGS. 8, 10, 11, and 16. FIG. Fig. 10 shows the main part of the flow control flow when the thermostat is off. FIG. 16 is a time chart of thermostat on → off compressor operation → stop wind speed control.

  In this case, the control from the start of the heating operation to the thermostat on, the subsequent thermostat off, and the intermediate heat exchange temperature is the same as (A) described above.

  From step S242 in FIG. 7 to step S300 in FIG. 8, it is checked in step S305 whether or not the compressor is in operation. Since the compressor is stopped based on the premise, the process proceeds to step S313 and compression is performed when the thermostat is off. During machine operation → Stop Enters wind speed control. From step S313, the process jumps to step S600 in FIG. 11, where the wind speed is set in the same manner as described above, and the heating operation is performed.

  Thus, when the thermostat is turned off and the compressor is changed to stop at the same time, as shown in the time chart of FIG. 16, from the compressor stop to the time up of the OF light wind timer, the wind speed setting is performed with the upper wind speed as a slight wind. From the time up of the OF light wind timer, the super-wind speed is set. This state continues until the compressor resumes operation in step S305 in FIG. 8 or until the thermostat is turned on in step S225 in FIG.

  When the compressor resumes operation with the thermostat off, the process proceeds from step S305 in FIG. 8 to step S310, and the compressor history flag is turned off in step S611 in FIG. When the thermostat is off at S312 Compressor is stopped → Operation Wind speed control is entered. The process jumps from step S312 to step S500 in FIG. 10, and it is checked in step S505 whether the compressor timer has started.

  This compressor timer is a period of time that is set to stabilize the operation state of the indoor unit where the thermostat is off and to quickly stabilize the refrigeration cycle after the compressor starts operation. In the example, it was 3 minutes.

  In this case, since the compressor timer has not yet started, the compressor timer is started in step S506, the compressor timer is checked for time-up in step S510, and if not, the wind speed is exceeded in step S515. The light wind is set, and the process returns from step S580 to step S380 in FIG. 8, step S280 in FIG. 7, and step S137 in FIG. 6, and the heating operation is performed.

  This state continues until the compressor timer expires in step S510 in FIG. 10. When the timer expires, the compressor timer is reset in step S511, the compressor history flag is turned on in step S512, and the 3-minute flag is initially turned off. To.

  In the next control cycle, since the compressor history flag checked in step S310 in FIG. 8 is turned on in step S512 in FIG. 10, the compressor is in operation from step S310 to step S311. Then, the process jumps to step S400 in FIG. 9, the initial 3 minute flag is checked in step S405, and since this flag is turned off in step S512 in FIG. 10, the process proceeds to step S407, and the repeated wind speed in FIG. Enter control and repeat.

This state continues until the thermostat is turned on in step S225 of FIG. 7, and when the thermostat is turned on, the above-described thermostat on control cycle starting from step S247 is repeated.
(C) Thermostat on at the start of heating operation, then thermostat off, low heat exchange temperature, then thermostat on, then (12) Control after thermostat off, low heat exchange temperature, then thermostat on (C) using FIG. I will explain.

  In this case, the control from the start of the heating operation to the thermostat on and then to the thermostat off is the same as described above.

  If the thermostat state is changed to OFF in step S225 of FIG. 7, the thermostat history flag is checked in step S230. Since the thermostat history flag remains on, the process proceeds to step S235, where the heat exchange temperature is the medium heat exchange temperature. It is checked whether the state is equal to or higher than T1. Since the heat exchanger temperature is in a state of low heat exchange temperature based on the premise, the process proceeds from step S240 to step S241, and the blower is stopped.

  This state continues until the thermostat is turned on in step S225. When the thermostat is turned on, the above-described thermostat-on control cycle starting from step S247 is repeated. Further, when the temperature of the heat exchanger rises to the intermediate heat exchange temperature in step S235 in the middle of the repetition while the thermostat is off, the flow shifts to the above-described air temperature control during the intermediate heat exchange temperature in step S242.

At this time, if the compressor is operating, during operation of the compressor in step S311 in FIG. 8, the thermostat is turned on to off, or the wind speed control is performed as described above. If the compressor is not operating, when the thermostat is off in step S313, the compressor is operating and stopped. The wind speed control is performed as described above.
(D) Thermostat off at the start of heating operation, high heat exchange temperature, and then thermostat on Next, control when the heating of the indoor unit is started and the thermostat is off will be described with reference to FIG.

  In this case, the control up to step S136 in FIG. 6 is the same as described above. The process jumps from step S136 to step S200 in FIG. 7, and the thermostat history flag is checked in step S205. Since this flag is turned off at the start of operation at the beginning of the operation mode being switched to the heating operation mode, the process proceeds to step S215. Check if the thermostat is off.

  Since the thermostat is off by assumption, the process proceeds to step S216, the heat exchange timer is reset, and the heat exchange temperature is checked in step S245.

  This heat exchanger timer is a state in which the heat exchanger is hot and the thermostat is off immediately after starting the heating operation, when the heat in the indoor unit is heated and the detected temperature of the suction temperature sensor is significantly different from the room temperature. The user's intention is to start heating, and the temperature of the heat exchanger is high, so there is no danger of cold air blowing out. Since it is necessary to reduce the difference between the detected temperature and room temperature, it is provided to control the blower as if the thermostat is on, and to return to normal thermostat control after a predetermined time. In the example, it was 3 minutes.

  Since the heat exchange temperature is higher than T3, which is a high heat exchange temperature condition, the process proceeds from step S245 to step S246, where the heat exchange timer is started, and various timers used for controlling the blower when the thermostat is off are set in step S247. Next, in step S250, the thermostat history flag is turned on, the initial 3-minute flag is turned on, the compressor history flag is turned on, and in step S251, the wind speed is set to the control wind speed when the thermostat is turned on, and the process proceeds to step 6 through step S280. The process returns to step S137.

  In the next control, since the thermostat history flag is turned on in step S250, the process proceeds from step S205 to step S210, where it is checked whether the heat exchange timer is started and the heat exchange timer is started. Proceeding to step S220, the heat exchange timer is checked for time-up, and if time is not up, the process goes to step S247.

  Thereafter, the control is repeated as if the thermostat was on in the control cycle of steps S247, S250, S251, S280, S137, S105, S131, S135, S136, S200, S205, S210, S220, and S247. This control cycle continues until the heat exchange timer expires in step S220, and when the time expires, the state of the thermostat is checked in step S225.

  Control as if the thermostat is on as described above is that the compressor is operated while the indoor unit is stopped, and a small amount of refrigerant is flowing to the stopped indoor unit to solve the refrigerant shortage. The temperature of the heat exchanger becomes high, the heat is trapped in the indoor unit, the suction temperature sensor is affected by the heat, and the thermostat is turned off even though the room temperature is low due to deviation from the room temperature. In order to eliminate this state, only a limited time (time until the heat exchanger timer expires) is performed.

  If the thermostat is on in step S225, the process proceeds to step S247, and the normal thermostat-on heating operation described above is started in (A). If the thermostat is off in step S225, the process proceeds to steps S230 and S235, and since this limited time has passed, the difference between the detected temperature of the suction temperature sensor and the room temperature is no longer within the allowable value and is in a normal state. Then, the control returns to the control (A), (B) or (C) described above.

  As described above, the multi-room air conditioner of the embodiment has the third predetermined temperature (T3) in which the temperature of the heat exchanger of the indoor unit that has started operation in the heating mode is higher than the first predetermined temperature (T1). In the above case, even if the thermostat is off at the start of operation, the blower is operated for a predetermined time at a wind speed equal to or higher than the set wind speed, and after a predetermined time has elapsed, the routine proceeds to normal heating control by the thermostat.

  In general, a small amount of refrigerant flows through the heat exchanger to eliminate the refrigerant shortage, such as when the heating of the room is stopped while the compressor is operated while the other room is heating, and the blower is turned off. If the operation is not continued for a long time, the heat from the high-temperature refrigerant that flows to the heat exchanger inside the indoor unit is heated, and the blower is not turning, so the suction temperature sensor is strongly affected by this, and the detection temperature increases. Often the thermostat is turned off.

  In the multi-room type air conditioner of the embodiment, the temperature of the heat exchanger is sufficiently warm, so that the temperature of the heat exchanger is in a warm state that does not hinder the blowing of warm air, and the blower rotates. Since the cool air does not blow out and matches the user's intention to start heating, the blower is turned rather than rotating the blower at ultra-low speed operation to gradually discharge the heat inside the machine to eliminate the heat turbulence. Drive immediately.

  Thus, when the temperature of the heat exchanger when starting operation in the heating mode is a temperature that is sufficiently higher than the third predetermined temperature (T3), the fan is operated even if the thermostat is off, Supply warm air indoors. Thereby, heating can be started in the room and the satisfaction of the user can be increased.

  Also, when the predetermined time has passed, the control returns to the original control by turning on and off the thermostat, so that the room temperature does not become too high. Thus, even when the heat exchanger becomes hot at the time of stoppage and the thermostat is turned off due to a malfunction, the thermostat can be returned to a normal state in a short time while following the user's intention.

For this reason, it is possible to provide a multi-room air conditioner that returns the thermostat to a normal state in a short time while following the user's intention.
(E) Thermostat off at the start of heating operation, medium / low heat exchange temperature, and then thermostat on In this case, the process jumps from step S136 in FIG. 6 to step S200 in FIG. 7, passes through steps S205, S215, and S216, and in step S245. The control is the same as that in (D) until the temperature is checked. Since the heat exchange temperature is lower than T3, which is a medium / low heat exchange temperature, the process proceeds from step S245 to step S252, the wind speed is set to ultra-fine wind, and the process returns from step S280 to step S137 in FIG. I do.

  Thereafter, the control cycle of steps S137, S105, S131, S135, S136, S200, S205, S215, S216, S245, S252, S280, and S137 is set, and this control cycle is set to a super-wind, and the thermostat is turned on in step S215. Repeat until. When the thermostat is turned on, the process proceeds from step S215 to step S247. Thereafter, the control cycle of steps S247, S250, S251, S280, S137, S105, S131, S135, S136, S200, S205, S210, S225, and S247 is performed. The thermostat is turned on.

  As described above, according to the multi-room air conditioner according to claim 1, in the heating operation of a plurality of indoor units connected to the same outdoor unit, the thermostat-off or stop indoor unit and the thermostat-on room When there is a mixture of units, a small amount of refrigerant is allowed to flow through the thermostat off or stop indoor unit to prevent shortage of refrigerants. When the heat exchanger temperature of the thermostat-off indoor unit is equal to or higher than the first predetermined temperature (T1) when both the thermostat-on indoor unit and the thermostat-on indoor unit are mixed, The vehicle is operated with a wind speed pattern composed of two or more wind speeds including a wind speed less than the selectable minimum wind speed.

  As a result, if the temperature of the heat exchanger of the indoor unit that is thermostatted off is too high and the effect on the suction temperature sensor is too great, operate the blower and send room air around the suction temperature sensor to Make sure that the temperature detected by the temperature sensor does not deviate significantly from the room temperature.

  At this time, the wind speed is divided into two or more stages, and at least one of the stages is set to a wind speed higher than the minimum wind speed that can be set by the user with a remote controller or the like. The minimum wind speed that can be set by the user with the remote control is required to allow the air conditioner to operate without any problems at that wind speed, and the thermostat operation and return characteristics do not at least become a practical obstacle. It is stipulated in.

  In this way, since the wind speed pattern of the air blow when the thermostat is off includes the time when operating at a wind speed higher than the minimum wind speed, the thermostat can be operated and restored without any problem by operating at this wind speed for the required time. The thermostat will return too slowly and there is no risk of overheating.

  At this time, at least one stage of the wind speed is set to a wind speed lower than the minimum wind speed that the user can set with the remote controller. As a result, the amount of heat exchange between the refrigerant and the intake air is reduced, there is no risk of refrigerant shortage, and the intake air always flows around the intake temperature sensor at a low speed. Can be reduced.

  In addition, as described above, suction air always flows around the suction temperature sensor at a low speed, so the suction temperature sensor is exposed to the suction air including the surroundings, so it operates at a wind speed higher than the above-mentioned minimum wind speed. In addition, the time required for determining whether or not the intake air temperature has reached the return temperature of the thermostat can be shortened, and the amount of heat exchange is reduced accordingly, and overheating is suppressed.

  For this reason, it is possible to obtain a multi-room air conditioner that increases the accuracy of detecting the intake air temperature and increases the temperature adjustment accuracy of the indoor air while avoiding the shortage of refrigerant and suppressing overheating.

  In the multi-room air conditioner according to claim 2, the wind speed pattern includes repetition of a basic wind speed pattern in which the two or more wind speeds are combined in time series.

  As a result, the temperature at the outlet of the indoor heat exchanger is heated according to the wind speed above the minimum wind speed at which the thermostat is reliably operated and restored, and the opening of the expansion valve that is slightly opened to suppress the accumulation of refrigerant. Since it is operated repeatedly in combination with an ultra-low wind speed that is set to be higher than during operation, the thermostat reliably recovers when it is operated at a wind speed higher than the minimum wind speed when the suction temperature falls, and overheating does not occur.

  In addition, when operating at a wind speed higher than the minimum wind speed, a small amount of refrigerant accumulates, but since this accumulation is also eliminated during ultra-low wind speed operation, a slight accumulation of refrigerant and elimination of the accumulation are repeated. In addition, accumulation of a large amount of refrigerant that interferes with the operation of the refrigeration cycle is avoided. In the examples, the above ultra-low wind speed was set to 1/3 or more of the minimum wind speed and 1/2 or less of the rated wind speed, and good results were obtained.

  For this reason, it is possible to obtain a multi-room air conditioner that avoids refrigerant shortage, reliably suppresses overheating, and reliably adjusts the temperature of the room.

  According to the multi-room air conditioner according to claim 3, when the heat exchanger temperature of the thermostat-off indoor unit is equal to or higher than the first predetermined temperature (T1), the blower is not stopped and the set wind speed or less. A wind speed pattern composed of three or more wind speeds is operated.

  As a result, operation at a set wind speed higher than the minimum wind speed is entered, so that the detection temperature of the suction temperature sensor approaches the suction temperature quickly and the operation time at the set wind speed at which overheating tends to occur is shortened, and overheating is unlikely to occur. Become. In addition, it is easy to change the speed of the blower from the set wind speed to the ultra-low wind speed as described above, but the change in the wind speed is too rapid, which may make the user feel uncomfortable and disturb the calmness of the room. is there.

  For this reason, when decelerating from the set wind speed to the ultra-low wind speed, a time for operating at the intermediate wind speed is provided in the middle so that the wind speed does not change suddenly, and the user does not feel uncomfortable. On the other hand, when increasing the speed, as described above, by slowly accelerating according to the current capacity of the power source and the current limit of the driver, abrupt changes in the wind speed are avoided, and the occupant's uncomfortable feeling is lightened to perform gentle air conditioning be able to.

  For this reason, it is possible to obtain a multi-room air conditioner that strongly suppresses overheating and reduces the uncomfortable feeling of the occupants.

  In the multi-room air conditioner according to claim 4, the wind speed pattern includes repetition of a basic wind speed pattern in which the three or more wind speeds are combined in time series.

  As a result, the operation and return of the thermostat are performed more reliably, and overheating is not performed, and accumulation of a large amount of refrigerant that interferes with the operation of the refrigeration cycle is avoided.

  For this reason, it is possible to obtain a multi-room air conditioner that strongly suppresses overheating, reduces an uncomfortable feeling of the occupants, and reliably adjusts the temperature of the room.

  According to the multi-room air conditioner of claim 5, the operation time of the ultra-low wind speed in the repeated operation is 0.4 to 0.7 of the interval between the repeated operations.

  As a result, the refrigerant that has accumulated in the heat exchanger when operating at the wind speed of the upper limit weak wind during repeated operation can be returned to the outdoor unit, and refrigerant shortage can be improved. When the operating time of ultra-low wind speed is less than 0.4 of the interval between repeated operations, the ability to return the refrigerant accumulated in the heat exchanger to the outdoor unit is insufficient, and the refrigerant that gradually accumulates in the heat exchanger every time it is repeated The risk of falling into a refrigerant shortage eventually increases.

  In addition, if the operating time of ultra-low wind speed exceeds 0.7, which is the interval between repeated operations, the difference between the detection temperature of the suction temperature sensor and room temperature increases due to the effect of the heat exchanger temperature, and within the upper limit weak wind operating time. The difference between the suction temperature sensor and the room temperature does not fall within the allowable range, the delay in thermostat on increases, the fluctuation of the room temperature increases, and the temperature distribution in the room during ultra low wind speed operation is not uniform. It becomes worse and the uniformity cannot be recovered within the upper limit low wind operation time, and the air conditioning quality deteriorates.

  Therefore, it is possible to obtain a multi-room air conditioner that saves energy while maintaining the thermal sensation of the occupants.

  According to the multi-room air conditioner according to claim 6, when all the indoor units in operation are in a thermostat-off state in the heating operation of the plurality of indoor units, heat exchange of the thermostat-off indoor units is performed. When the chamber temperature is equal to or higher than the first predetermined temperature (T1), the operating wind speed of the blower is set to be equal to or lower than the set wind speed and is monotonously decreased with time to an ultra-low wind speed lower than the lowest wind speed that can be manually selected.

  Thereby, since the compressor is stopped, the high-temperature refrigerant does not flow in the heat exchanger, the heat in the machine is gradually dissipated, and the heat influence from the heat exchanger on the suction temperature sensor is also weakened. For this reason, the difference between the temperature detected by the suction temperature sensor and the temperature of the suction air is reduced, and even if the wind speed is gradually reduced, there is no problem and energy saving of the blower can be measured. It is also possible to prevent sudden changes in wind speed.

  For this reason, it is possible to obtain a multi-room air conditioner that saves energy while avoiding refrigerant shortage and suppressing overheating.

  Moreover, according to the multi-room air conditioner according to claim 7, the temperature of the heat exchanger of the indoor unit that has started operation in the heating mode is a third predetermined temperature (T1) higher than the first predetermined temperature (T1). In the case of T3) or more, even if the thermostat is off at the start of operation, the fan is operated for a predetermined time at a wind speed equal to or higher than the set wind speed, and after a predetermined time has elapsed, the routine proceeds to normal heating control by the thermostat.

  Thereby, since the temperature of the heat exchanger is sufficiently warm, the temperature of the heat exchanger is in a warm state that does not hinder the blowing of hot air, and even if the blower rotates, cold air does not blow out, Since it also matches the user's intention to start heating, the fan is operated immediately rather than turning the fan at ultra-low speed operation to gradually discharge the heat inside the machine to eliminate the heat buildup.

  Thus, when the temperature of the heat exchanger when starting operation in the heating mode is a temperature that is sufficiently higher than the third predetermined temperature (T3), the fan is operated even if the thermostat is off, Supply warm air indoors. Thereby, heating can be started in the room and the satisfaction of the user can be increased.

  Also, when the predetermined time has passed, the control returns to the original control by turning on and off the thermostat, so that the room temperature does not become too high. Thus, even when the heat exchanger becomes hot at the time of stoppage and the thermostat is turned off due to a malfunction, the thermostat can be returned to a normal state in a short time while following the user's intention.

  Therefore, it is possible to obtain a multi-room air conditioner in which the thermostat returns to a normal state in a short time while following the user's intention.

1 Air conditioner 2a Indoor unit a
2b Indoor unit b
2c Indoor unit c
5a Remote control a
5b Remote control b
5c Remote control c
6 Outdoor unit 8 Connection pipe 10 Control unit 20 Housing 21 Housing body 21c Hanging bolt 25 Cosmetic panel 27 Air inlet 29 Air outlet 33 Indoor heat exchanger 35 Dew tray 37 Drain pipe 70 Refrigeration cycle 72 Refrigerant cycle switching valve 73 Outdoor Heat Exchanger 74 Air-Conditioning and Throttle Device 75 Compressor 78 Narrow Pipe Connection Valve 79 Thick Pipe Connection Valve 81 Arm Drive Device 83 Opening / Closing Arm 171 Suction Temperature Sensor 231 Filter 240 Cleaning Device 251 Suction Panel 290 Blowing Air Path 291 Vertical Air Direction Plate 311 Blower 313 Blower motor 396a Transceiver a
396b Transmission / reception unit b
396c Transmission / reception unit c
903 Ceiling

Claims (6)

A plurality of heating operation of the indoor unit connected to the same outdoor unit, a state where the indoor unit or stopping the indoor unit and the thermostat on the indoor unit of the thermostat-off are mixed, the indoor unit or the stop of the thermostat-off in multifocal flow a small amount of refrigerant in the indoor unit of the room air conditioner,
In the heating operation of the plurality of indoor units, wherein the indoor unit of the thermostat off a when the thermostat on the indoor unit and are mixed, the temperature of the heat exchanger of the indoor unit of the thermostat off the first predetermined temperature ( in the case of T1) or more, and manual selectable minimum wind speed or wind speed blower of the indoor unit of the thermostat-off, in wind speed pattern composed of two or more wind speed including wind speed of less than manually selectable minimum wind speed Drive ,
In the heating operation of a plurality of indoor units, when the stopped indoor unit and the thermostat-on indoor unit coexist, the operation of the blower of the stopped indoor unit is stopped, and the stopped indoor unit starts operation When the temperature of the heat exchanger of the indoor unit that has started operation is equal to or higher than the third predetermined temperature (T3) higher than the first predetermined temperature (T1), the set wind speed even if the thermostat is off A multi-room air conditioner that operates the blower of the indoor unit that has started the operation for a predetermined time at the above wind speed .   2. The multi-room air conditioner according to claim 1, wherein the wind speed pattern includes repetition of a basic wind speed pattern in which the two or more wind speeds are combined in time series.   In Claim 1, when the heat exchanger temperature of the thermostat-off indoor unit is equal to or higher than the first predetermined temperature (T1), the wind speed pattern configured by three or more stages of wind speeds below the set wind speed without stopping the blower A multi-room air conditioner that operates on   4. The multi-room air conditioner according to claim 3, wherein the wind speed pattern includes repetition of a basic wind speed pattern in which the three or more wind speeds are combined in time series.   5. The multi-room air conditioner according to claim 2, wherein the operation time of the ultra low wind speed in the repeated operation is 0.4 to 0.7 of the interval of the repeated operation.   In Claim 1 or 3, when all the indoor units under operation are in a thermostat-off state in the heating operation of the plurality of indoor units, the heat exchanger temperature of the thermostat-off indoor unit is a first predetermined temperature (T1). ) In the above case, the multi-room air conditioner is characterized in that the operating wind speed of the blower is set below the set wind speed and monotonously decreases with time to an ultra-low wind speed less than the lowest wind speed that can be manually selected.

Images