JP6458533B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner, and more particularly to operation control at the start of heating operation.

  As a conventional air conditioner, an indoor heat exchanger temperature sensor for detecting the temperature of the indoor heat exchanger is provided, and at the start of heating operation, the compressor is started, and the detected value of the indoor heat exchanger temperature sensor is equal to or greater than a predetermined value. If it becomes, there exists a thing which raises the rotation speed of an indoor fan from very low rotation to low rotation (for example, patent document 1). As a result, it is possible to prevent the cool air from being blown out when the indoor fan is operated before the temperature of the indoor heat exchanger is sufficiently increased, and to improve the comfort at the start of the heating operation of the air conditioner. Such control is called cold air prevention control.

  In a multi-type air conditioner in which multiple indoor units are connected to one outdoor unit, especially when the piping connecting the indoor unit and the outdoor unit is long, the circulation of the refrigerant takes time, so the temperature rise of the indoor heat exchanger is slow. It does not exceed the predetermined value. As a result, it takes time before the warm air can be blown from the indoor unit. In the air conditioner described in Patent Document 1, with respect to such a problem, the rotational speed of the indoor fan is increased when a predetermined time has elapsed from the start of operation of the compressor. This prevents the problem that the warm air blowing is not started and the start-up of the heating is delayed because the indoor heat exchanger temperature does not exceed the predetermined value.

  On the other hand, if the rotational speed of the compressor is driven at the maximum rotational speed immediately after startup, a large amount of refrigerating machine oil accumulated in the compressor is discharged, and the reliability of the compressor is lowered. For this reason, the compressor performs control to gradually increase the rotational speed from a low rotational speed after startup.

  In the air conditioner described in Patent Document 1, the rotational speed of the indoor fan is increased after a predetermined time has elapsed from the start of operation of the compressor even if the indoor heat exchanger temperature does not exceed the predetermined value. The wind is not warm enough.

  On the other hand, if the rotational speed of the compressor reaches the maximum rotational speed before the predetermined time has elapsed, the temperature of the indoor heat exchanger rises, and warm air warmed to such an extent that the user's comfort is not impaired. Although there is a possibility that the air can be blown out, the air conditioner described in Patent Document 1 does not increase the rotational speed of the indoor fan unless a predetermined time elapses. As a result, the start-up of the heating operation is delayed.

JP 2002-174450 A

  The present invention has been made to solve such a problem, and it is an object of the present invention to provide an air conditioner that improves the comfort at the start of heating operation and prevents the start-up of heating from being delayed. It is what.

  The air conditioner of the present invention includes a compressor, an indoor heat exchanger, an indoor fan, an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, and a control means for controlling the indoor fan. The air conditioner is provided, wherein the control means operates the indoor fan at a first rotational speed simultaneously with the start of the compressor at the time of starting the heating operation of the air conditioner, and starts the compressor When the detected value of the indoor heat exchanger temperature detecting means is equal to or higher than a predetermined temperature, the indoor fan is operated at a second rotational speed larger than the first rotational speed, and the indoor heat exchange is performed. When the detected value of the temperature detector is lower than a predetermined temperature, the detected value of the indoor heat exchanger temperature detector is increased per unit time after increasing the rotational speed of the compressor to the maximum rotational speed. The amount of increase is calculated For more value, the holding current rotational speed of the indoor fan, if the increment is less than the predetermined value, is characterized by increasing the rotational speed of the indoor fan by a predetermined rotation speed.

  Preferably, the detected value of the indoor heat exchanger temperature detecting means is lower than a predetermined temperature, and the increase is performed when a predetermined time elapses after the rotation speed of the compressor is increased to the maximum rotation speed. Regardless of the amount, the indoor fan is operated at the second rotational speed.

  ADVANTAGE OF THE INVENTION According to this invention, the comfort at the time of heating operation start can be improved, and the rise time of heating can be shortened.

It is the schematic which shows the whole refrigerating cycle of the air conditioning apparatus of this embodiment. It is a figure which shows the change of the indoor fan rotation speed and indoor heat exchanger temperature of the air conditioning apparatus when not implementing this invention. It is a flowchart which shows the control method of the air conditioning apparatus of this invention. It is a flowchart which shows the control method of the air conditioning apparatus of this invention.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The present invention is not limited to the following embodiments, and can be variously modified without departing from the gist of the present invention.

  As shown in FIG. 1 (A), an air conditioner 1 in the first embodiment includes an outdoor unit 2 installed outdoors, and an indoor unit 3 connected to the outdoor unit 2 with a liquid pipe 4 and a gas pipe 5. It has. Specifically, the liquid pipe 4 has one end connected to the closing valve 25 of the outdoor unit 2 and the other end connected to the liquid pipe connecting portion 34 of the indoor unit 3. The gas pipe 5 has one end connected to the closing valve 26 of the outdoor unit 2 and the other end connected to the gas pipe connecting portion 35 of the indoor unit 3. The refrigerant circuit 10 of the air conditioner 1 is configured as described above.

  First, the outdoor unit 2 will be described. The outdoor unit 2 includes a compressor 20, a four-way valve 22, an outdoor heat exchanger 23, a closing valve 25 to which one end of the liquid pipe 4 is connected, a closing valve 26 to which one end of the gas pipe 5 is connected, An accumulator 21 and an outdoor fan 24 are provided. And these each apparatus except the outdoor fan 24 is mutually connected by each refrigerant | coolant piping explained in full detail below, and the outdoor unit refrigerant circuit 10a which makes a part of the refrigerant circuit 10 is comprised.

  The compressor 20 is a variable-capacity compressor that can vary the operation capacity by being driven by a motor 201 whose rotational speed is controlled by an inverter (not shown). The refrigerant discharge side of the compressor 20 is connected to the port a of the four-way valve 22 by a discharge pipe 61, and the refrigerant suction side of the compressor 20 is connected to the refrigerant outflow side of the accumulator 21 by a suction pipe 66. Yes.

  The four-way valve 22 is a valve for switching the direction in which the refrigerant flows, and includes four ports a, b, c, and d. The port a is connected to the refrigerant discharge side of the compressor 20 by the discharge pipe 61 as described above. The port b is connected to one refrigerant inlet / outlet of the outdoor heat exchanger 23 by a refrigerant pipe 62. The port c is connected to the refrigerant inflow side of the accumulator 21 by a refrigerant pipe 65. The port d is connected to the shutoff valve 26 and the outdoor unit gas pipe 64.

  The outdoor heat exchanger 23 exchanges heat between the refrigerant and the outside air taken into the outdoor unit 2 by the rotation of the outdoor fan 24 described later. As described above, one refrigerant inlet / outlet of the outdoor heat exchanger 23 is connected to the port b of the four-way valve 22 by the refrigerant pipe 62, and the other refrigerant inlet / outlet is connected to the closing valve 25 by the outdoor unit liquid pipe 63.

  The expansion valve 27 is provided in the outdoor unit liquid pipe 63. The expansion valve 27 is an electronic expansion valve. A detailed description of the opening degree control of the expansion valve 27 will be described later.

  The outdoor fan 24 is formed of a resin material and is disposed in the vicinity of the outdoor heat exchanger 23. The outdoor fan 24 is rotated by a fan motor (not shown) to take outside air into the outdoor unit 2 from a suction port (not shown), and the outdoor air heat exchanged with the refrigerant in the outdoor heat exchanger 23 is sent from the blower outlet (not shown) to the outdoor unit 2. To the outside.

  As described above, in the accumulator 21, the refrigerant inflow side is connected to the port c of the four-way valve 22 by the refrigerant pipe 65, and the refrigerant outflow side is connected to the refrigerant intake side of the compressor 20 by the intake pipe 66. The accumulator 21 separates the refrigerant flowing into the accumulator 21 from the refrigerant pipe 65 into a gas refrigerant and a liquid refrigerant and causes the compressor 20 to suck only the gas refrigerant.

  In addition to the configuration described above, the outdoor unit 2 is provided with various sensors. As shown in FIG. 1A, the discharge pipe 61 is provided with a discharge temperature sensor 73 that detects the temperature of the refrigerant discharged from the compressor 20.

  The outdoor heat exchanger 23 is provided with an outdoor heat exchanger temperature sensor 75 for detecting the temperature of the refrigerant flowing out of the outdoor heat exchanger 23 or flowing into the outdoor heat exchanger 23. An outdoor air temperature sensor 76 that detects the temperature of the outside air flowing into the outdoor unit 2, that is, the outside air temperature, is provided near the suction port (not shown) of the outdoor unit 2.

  Further, the outdoor unit 2 is provided with an outdoor unit control means 100. The outdoor unit control means 100 is mounted on a control board stored in an electrical component box (not shown) of the outdoor unit 2. As shown in FIG. 1B, the outdoor unit control means 100 includes a CPU 110, a storage unit 120, a communication unit 130, a detection value input unit 140, and a compressor control unit 150.

  The storage unit 120 includes a ROM and a RAM, and stores a control program for the outdoor unit 2, detection values corresponding to detection signals from various sensors, control states of the compressor 20 and the outdoor fan 24, and the like. The communication unit 130 is an interface for performing communication with the indoor unit 3. The detection value input unit 140 captures detection results from various sensors of the outdoor unit 2 and outputs them to the CPU 110. The compressor control unit 150 performs control so that the compressor 20 is operated at the number of revolutions necessary for exhibiting the capability requested by the user.

  The CPU 110 takes in the detection results of the various sensors of the outdoor unit 2 described above via the detection value input unit 140. Further, the CPU 110 takes in a control signal transmitted from the indoor unit 3 via the communication unit 130. Further, the CPU 110 performs drive control of the compressor 20 and the outdoor fan 24 based on the captured control signal. Furthermore, the CPU 110 performs switching control of the four-way valve 22 based on the acquired detection result and control signal.

  Next, the indoor unit 3 will be described with reference to FIG. The indoor unit 3 includes an indoor heat exchanger 31, a liquid pipe connection part 34 to which the other end of the liquid pipe 4 is connected, a gas pipe connection part 35 to which the other end of the gas pipe 5 is connected, an indoor fan 33, It has. And these each apparatus except the indoor fan 33 is mutually connected by each refrigerant | coolant piping explained in full detail below, and the indoor unit refrigerant circuit 10b which comprises a part of refrigerant circuit 10 is comprised.

  The indoor heat exchanger 31 exchanges heat between the refrigerant and the indoor air taken into the interior of the indoor unit 3 from a suction port (not shown) by an indoor fan 33, which will be described later. The other refrigerant inlet / outlet port is connected to the gas pipe connecting portion 35 via the indoor unit gas pipe 69. The indoor heat exchanger 31 functions as an evaporator when the indoor unit 3 performs a cooling operation, and functions as a condenser when the indoor unit 3 performs a heating operation. In addition, in the liquid pipe connection part 34 and the gas pipe connection part 35, each refrigerant | coolant piping is connected by welding, a flare nut, etc.

  The indoor fan 33 is disposed in the vicinity of the indoor heat exchanger 31 and is rotated by a fan motor (not shown) to take indoor air into the indoor unit 3 from a suction port (not shown). The room air that has undergone heat exchange is blown into the room through a blowout port (not shown).

  In addition to the configuration described above, the indoor unit 3 is provided with various sensors. The indoor heat exchanger 31 is provided with an indoor heat exchanger temperature sensor 78 that detects the temperature of the refrigerant passing through the indoor heat exchanger 31. The indoor unit 3 is provided with an indoor temperature sensor 79 that detects the temperature of indoor air, that is, the indoor temperature. The mounting position of the indoor temperature sensor 79 is preferably arranged away from heat-generating components such as the indoor heat exchanger 31 and the control board (indoor unit control means 200) provided in the indoor unit 3. Further, instead of attaching to the indoor unit 3, it may be attached to a remote controller (not shown).

  The indoor unit 3 is provided with an indoor unit control means 200. The indoor unit control means 200 is mounted on a control board stored in an electrical component box (not shown) of the indoor unit 3. As shown in FIG. 1B, the indoor unit control means 200 includes a CPU 210, a storage unit 220, a communication unit 230, a detection value input unit 240, and an indoor fan control unit 250.

  The storage unit 220 includes a ROM and a RAM, and stores a control program for the indoor unit 3, detection values corresponding to detection signals from various sensors, a control state of the indoor fan 33, and the like. The communication unit 230 is an interface for performing communication with the outdoor unit 2. The detection value input unit 240 captures detection results from various sensors of the indoor unit 3 and outputs them to the CPU 210. The indoor fan control unit 250 performs control to prevent the indoor fan 33 from operating at the number of revolutions necessary for exhibiting the capability requested by the user, and performs cold air prevention control to be described later.

  The CPU 210 takes in the detection results of the various sensors of the indoor unit 3 described above via the detection value input unit 240. Further, the CPU 210 takes in a control signal transmitted from the outdoor unit 2 via the communication unit 230. Further, the CPU 210 performs drive control of the indoor fan 33 based on the captured control signal. Further, the CPU 210 is provided with time measuring means (timer T) (not shown), and is used for cold air prevention control, which will be described later.

  Next, the flow of the refrigerant and the operation of each part in the refrigerant circuit 10 during the air conditioning operation of the air-conditioning apparatus 1 in the present embodiment will be described with reference to FIG. In the following description, the case where the indoor unit 3 performs the heating operation will be described, and the detailed description of the case where the indoor unit 3 performs the cooling operation will be omitted. Moreover, the arrow in FIG. 1 (A) has shown the flow of the refrigerant | coolant at the time of heating operation.

  As shown in FIG. 1 (A), when the indoor unit 3 performs a heating operation, the outdoor unit control means 100 is in a state where the four-way valve 22 is indicated by a solid line, that is, the port a and the port d of the four-way valve 22 communicate with each other. And switching so that the port b and the port c communicate with each other. Thereby, the outdoor heat exchanger 23 functions as an evaporator, and the indoor heat exchanger 31 functions as a condenser.

  The high-pressure refrigerant discharged from the compressor 20 flows through the discharge pipe 61 and flows into the four-way valve 22, flows from the four-way valve 22 through the outdoor unit gas pipe 64, and flows into the gas pipe 5 through the closing valve 26. The refrigerant that has flowed through the gas pipe 5 flows into the indoor unit gas pipe 69 of the indoor unit 3 through the gas pipe connecting portion 35. The refrigerant flowing through the indoor unit gas pipe 69 flows into the indoor heat exchanger 31 and condenses by exchanging heat with the indoor air taken into the interior of the indoor unit 3 by the rotation of the indoor fan 33. As described above, the indoor heat exchanger 31 functions as a condenser, and heat is exchanged with the refrigerant in the indoor heat exchanger 31, and heated indoor air is blown into the room from a blower outlet (not shown), whereby the indoor unit 3 The room where the is installed is heated. The refrigerant flowing out of the indoor heat exchanger 31 flows through the indoor unit liquid pipe 68 and flows into the liquid pipe 4 via the liquid pipe connecting portion 34.

  The refrigerant flowing through the liquid pipe 4 and flowing into the outdoor unit 2 through the closing valve 25 flows into the expansion valve 27 provided in the outdoor unit liquid pipe 63. The refrigerant that has passed through the expansion valve 27 is decompressed and becomes a low-pressure refrigerant. The refrigerant that has passed through the expansion valve 27 then flows into the outdoor heat exchanger 23. The refrigerant flowing into the outdoor heat exchanger 23 evaporates by exchanging heat with the outside air taken into the outdoor unit 2 by the rotation of the outdoor fan 24. The refrigerant flowing out of the outdoor heat exchanger 23 sequentially flows through the refrigerant pipe 62, the four-way valve 22, the refrigerant pipe 65, the accumulator 21, and the suction pipe 66, and is sucked into the compressor 20 and compressed again. As described above, the heating operation of the air conditioner 1 is performed by circulating the refrigerant through the refrigerant circuit 10.

  When the indoor unit 3 performs a cooling operation, the outdoor unit control means 100 is configured so that the four-way valve 22 is in a state indicated by a broken line, that is, the port a and the port b of the four-way valve 22 communicate with each other. Switch so that port d communicates. Thereby, the outdoor heat exchanger 23 functions as a condenser, and the indoor heat exchanger 31 functions as an evaporator.

  Next, a conventional control method at the start of the heating operation of the air conditioner 1 will be described in detail with reference to FIG.

  When the air conditioner 1 receives a heating operation start command by a user's remote control operation or the like, the air conditioner 1 activates the compressor 20 to circulate the refrigerant in the refrigerant circuit 10.

  After the compressor 20 is started, cold air prevention control is performed in which the rotational speed N of the indoor fan 33 is operated at an extremely low speed N1 until the temperature Tc of the indoor heat exchanger 31 reaches a predetermined temperature Tcs. The reason why the indoor fan 33 is operated immediately after the compressor 20 is started is to circulate indoor air and accurately detect the indoor temperature, but the indoor heat exchanger 31 has not yet been warmed. Nevertheless, when the indoor fan 33 is operated at a high speed, cold air close to the room temperature is blown out from the outlet (not shown) of the indoor unit 3 and the user feels chilly. Therefore, the extremely low rotation N1 is a low rotation that does not reach the user from the air blown from the air outlet (not shown) of the indoor unit 3 even when the indoor fan 33 is operated. As shown in FIG. 2B, after the compressor 20 is started, the indoor heat exchanger temperature Tc increases, and when the indoor heat exchanger temperature Tc reaches a predetermined value Tcs, the rotational speed of the indoor fan 33 is set. The rotation speed is increased from the extremely low rotation N1 to the rotation speed (N2 in this case) corresponding to the capability requested by the user (release of the cool air prevention control).

  At this time, after starting, the compressor 20 gradually increases from a low rotational speed to a rotational speed necessary for exhibiting the capability requested from the indoor unit control unit 200 (approximately the maximum rotational speed when heating operation is started). To be controlled. This is because if the rotational speed of the compressor 20 is driven at the maximum rotational speed immediately after startup, a large amount of refrigerating machine oil accumulated in the compressor 20 is discharged and the reliability of the compressor 20 is lowered. .

  In addition, as a countermeasure when the condition that “the indoor heat exchanger temperature Tc is equal to or higher than the predetermined value Tcs”, which is the condition for canceling the cold air prevention control, is not satisfied even after a long time, a predetermined time from the start of operation of the compressor 20 When the time elapses, the rotational speed of the indoor fan 33 is increased. This is because, for example, in a multi-type air conditioner in which a plurality of indoor units 3 are connected to one outdoor unit 2, especially when the pipe connecting the indoor unit 2 and the outdoor unit 3 is long, it takes time to circulate the refrigerant. This is to solve the problem that the temperature of the heat exchanger 31 rises slowly and does not reach a predetermined value or higher, and as a result, it takes time until the warm air can be blown out from the indoor unit 3. . By increasing the rotational speed of the indoor fan 33 when a predetermined time has elapsed from the start of the operation of the compressor 20, the temperature of the indoor heat exchanger does not exceed a predetermined value, so that hot air blowing is not started and heating starts Is preventing the delay.

  However, in the case of the above control, when the predetermined time has elapsed from the start of the operation of the compressor 20, even if the indoor heat exchanger temperature does not exceed the predetermined value, the rotational speed of the indoor fan 33 is increased. There will be no wind and the comfort will be reduced. If the rotational speed of the compressor 20 at this time is not the maximum rotational speed, there is a possibility that the indoor heat exchanger temperature can be raised to a predetermined value by increasing the rotational speed of the compressor 20. If the rotational speed of the indoor fan 33 is increased after waiting for the rotational speed of 20 to increase, the comfort of the user can be improved without being hit by unwarmed wind.

  Therefore, at the time of starting the heating operation of the air conditioner 1, it is necessary to appropriately control the timing of increasing the rotational speed N of the indoor fan 33 after the compressor 20 is activated. The cold air prevention control, which is a feature of the present invention, will be described in detail below.

  3 and 4 are flowcharts showing the cold air prevention control of the air conditioner 1 at the time of activation. The number after ST represents the step number, Y represents Yes, and N represents No.

  This control is started by receiving a heating operation start command by a user's remote control operation or the like. First, heating operation is started in step ST101, and the compressor 20 is started. The compressor 20 performs control to gradually increase the rotational speed from the low rotational speed to the maximum rotational speed after startup. Subsequently, in step ST102, control is performed so that the rotational speed N of the indoor fan 33 becomes the extremely low rotational speed N1, which is the first rotational speed. The extremely low rotational speed N1 is low enough that the wind blown from the air outlet (not shown) of the indoor unit 3 does not reach the user even when the indoor fan 33 is operated as in the conventional control method shown in FIG. Thus, the rotation speed is not used during normal heating (and cooling) operation. In step ST103, the detected value Tc of the indoor heat exchanger temperature sensor 78 is input to the indoor unit control means 200. In the indoor unit control means 200, the detection value Tc is converted into digital data by the detection value input unit 240 and input to the CPU 210 as a detection value corresponding to the detection signal of the indoor heat exchanger temperature sensor 78. CPU 210 determines whether or not detected value Tc is equal to or higher than predetermined value Tcs, which is a predetermined temperature, according to a control program stored in storage unit 220 (step ST104).

  Here, the predetermined value Tcs is based on an experiment or the like in order to determine that the indoor heat exchanger 31 has been sufficiently warmed to the extent that hot air can be blown even when the rotational speed N of the indoor fan 33 is operated at a high speed. It is a predetermined value.

  If the detected value Tc is equal to or greater than the predetermined value Tcs (ST104-Y), the CPU 210 cancels the cool air prevention control, and the rotational speed N of the indoor fan 33 is greater than the extremely low rotational speed N1, and the user The system shifts to normal operation in which the engine speed is increased according to the required performance. When the detected value Tc is less than the predetermined value Tcs (ST104-N), the process proceeds to step ST105 and it is determined whether or not the rotational speed F of the compressor 20 is the maximum rotational speed Fmax (step ST105).

  If the rotation speed F of the compressor 20 is the maximum rotation speed Fmax in step ST105 (ST105-Y), the timer T provided in the CPU 210 is started (step ST106) and the process proceeds to step ST201 in FIG. When the rotation speed F of the compressor 20 is not the maximum rotation speed Fmax (ST105-N), the process returns to step ST103.

  In step ST201, the indoor heat exchanger temperature sensor 78 detects the temperature Tc of the indoor heat exchanger, and the detected value Tc is input to the indoor unit control means 200. In the indoor unit control means 200, the detection value Tc is converted into digital data by the detection value input unit 240 and input to the CPU 210 as a detection value corresponding to the detection signal of the indoor heat exchanger temperature sensor 78. CPU 210 stores detected value Tc in storage unit 220 as Tc0 (step ST202).

  Subsequently, in step ST203, it is determined whether or not the time measured by the timer T has passed a control interval time t0 (for example, 1 minute). When the control interval time t0 has passed, in step ST204, the indoor heat exchanger temperature at that time The sensor 78 detects the temperature Tc of the indoor heat exchanger, and the detected value Tc is input to the indoor unit control means 200. In the indoor unit control means 200, the detection value Tc is converted into digital data by the detection value input unit 240 and input to the CPU 210 as a detection value corresponding to the detection signal of the indoor heat exchanger temperature sensor 78. CPU 210 stores detected value Tc in storage unit 220 as Tc1 (step ST205).

  The CPU 210 calculates the increase amount (Tc1-Tc0 / t0) of the indoor heat exchanger temperature Tc per unit time (during t0) according to the control program stored in the storage unit 220, and the value is less than the predetermined value α. Is determined (step ST206). Here, the predetermined value α means that even if a predetermined time ts1 to be described later elapses after the rotation speed F of the compressor 20 reaches the maximum rotation speed Fmax while the increase amount of the indoor heat exchanger temperature Tc is less than α, A value that can be predicted that the indoor heat exchanger temperature Tc does not exceed the predetermined value Tcs (the temperature does not rise moderately) is set.

  When the increase amount (Tc1-Tc0 / t0) of the indoor heat exchanger temperature Tc during t0 is less than the predetermined value α (ST206-Y), the rotational speed N of the indoor fan 33 is set to the current rotational speed in step ST207. The number of revolutions is controlled to be the number of revolutions (N + n) increased by the number of revolutions n. Therefore, when the rotation speed of the compressor 20 is the maximum and the indoor heat exchanger temperature Tc does not rise, the amount of heat exchange in the indoor heat exchanger 31 is increased by increasing the rotation speed of the indoor fan 33. As a result, the heating capacity is increased, the indoor heat exchanger temperature Tc is increased, and the room temperature is increased. Thereafter, the process proceeds to step ST208. In step ST206, when the increase amount (Tc1-Tc0 / t0) of the indoor heat exchanger temperature Tc during t0 is equal to or greater than the predetermined value α (ST206-N), the process proceeds to step ST208.

  In step ST208, the indoor heat exchanger temperature sensor 78 detects the temperature Tc of the indoor heat exchanger, and the detected value Tc is input to the indoor unit control means 200. In the indoor unit control means 200, the detection value Tc is converted into digital data by the detection value input unit 240 and input to the CPU 210 as a detection value corresponding to the detection signal of the indoor heat exchanger temperature sensor 78. CPU 210 determines whether or not detected value Tc is equal to or greater than predetermined value Tcs in accordance with a control program stored in storage unit 220 (step ST209).

When the detected value Tc is equal to or greater than the predetermined value Tcs (ST209-Y), the CPU 210 increases the indoor heat exchanger temperature Tc to such an extent that the user does not feel the wind blown from the indoor unit 3 uncomfortable. Therefore, the cold wind prevention control is canceled, and the routine proceeds to “normal operation start” in FIG. When the detected value Tc is less than the predetermined value Tcs (ST209-N), the process proceeds to step ST210.
In step ST210, it is determined whether or not the time t of the timer T is equal to or greater than a predetermined time ts1. When the time t is equal to or greater than the predetermined time ts1 (ST210-Y), the cool air prevention control is canceled and the rotational speed N of the indoor fan 33 is increased to the rotational speed corresponding to the capability requested by the user. Move to “Normal operation start”. Thus, when the predetermined time ts1 has elapsed from the start of the operation of the compressor 20, the number of revolutions of the indoor fan 33 is increased so that the temperature of the indoor heat exchanger does not exceed a predetermined value, so that hot air blowing is started. This prevents the problem of delaying the start-up of heating.

  If the time t is less than the predetermined time ts1 (ST210-N), the process returns to step ST201. That is, it is determined again in steps ST201 to ST206 whether or not the increase amount of the indoor heat exchanger temperature Tc is less than the predetermined value α, and if it is less than the predetermined value α, the rotational speed N of the indoor fan 33 is set to the current rotational speed. The number of revolutions is increased to the number of revolutions (N + n) (step ST207). These are repeated until the indoor heat exchanger temperature Tc becomes equal to or higher than the predetermined value Tcs in step ST209 or the time t of the timer T becomes equal to or higher than the predetermined time t1 in step ST210.

  As described above, in the present embodiment, after the rotation speed of the compressor 20 is maximized, it is determined whether or not the increase amount (Tc1−Tc0 / t0) of the indoor heat exchanger temperature Tc is less than the predetermined value α. When the increase amount is less than the predetermined value α, the rotation speed N of the indoor fan 33 is controlled to be the rotation speed (N + n) obtained by increasing the rotation speed N of the indoor fan 33 by the predetermined rotation speed n. Therefore, when the rotation speed of the compressor 20 is the maximum and the indoor heat exchanger temperature Tc does not rise sharply, the heat exchange amount in the indoor heat exchanger 31 is increased by increasing the rotation speed of the indoor fan 33. . This improves the problem that the indoor heat exchanger temperature Tc rises and the indoor heat exchanger temperature does not exceed a predetermined value, so that hot air blowing is not started and the start-up of the heating is delayed.

DESCRIPTION OF SYMBOLS 1 Air conditioning apparatus 2 Outdoor unit 3 Indoor unit 20 Compressor 31 Indoor heat exchanger 33 Indoor fan

Claims (2)

A compressor, an indoor heat exchanger, an indoor fan,
An indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger;
An air conditioner comprising control means for controlling the indoor fan,
The control means includes
When the air conditioning apparatus starts heating operation, the indoor fan is operated at the first rotational speed simultaneously with the start of the compressor,
After the compressor is started, when the detected value of the indoor heat exchanger temperature detecting means is equal to or higher than a predetermined temperature, the indoor fan is rotated at a second rotational speed greater than the first rotational speed. Drive,
When the detected value of the indoor heat exchanger temperature detecting means is lower than a predetermined temperature, the unit of the detected value of the indoor heat exchanger temperature detecting means after increasing the rotational speed of the compressor to the maximum rotational speed The amount of increase per hour is calculated. If the amount of increase is equal to or greater than a predetermined value, the current rotational speed of the indoor fan is maintained. If the amount of increase is less than the predetermined value, the rotational speed of the indoor fan is determined. An air conditioner that is increased by a predetermined number of revolutions. The detected value of the indoor heat exchanger temperature detecting means is lower than a predetermined temperature, and when a predetermined time elapses after the rotation speed of the compressor is increased to the maximum rotation speed, the increase is not related to the increase amount. The air conditioner according to claim 1, wherein the indoor fan is operated at the second rotational speed.

Images