JP4893025B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner, and more specifically to a technique for improving the dehumidification (latent heat) capability by changing the sensible heat / latent heat ratio of an indoor heat exchanger during cooling cycle operation.

  The air conditioner of the air conditioning type has a refrigeration cycle including a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger. During heating operation, the compressor → the four-way valve → the indoor heat exchanger → the expansion valve → Recirculate refrigerant to outdoor heat exchanger → four-way valve → compressor, use indoor heat exchanger as condenser and outdoor heat exchanger as evaporator.

  On the other hand, during the cooling cycle operation including dehumidification, the refrigerant is circulated through the compressor → four-way valve → outdoor heat exchanger → expansion valve → indoor heat exchanger → four-way valve → compressor to evaporate the indoor heat exchanger. And outdoor heat exchangers are used as condensers. At the time of dehumidification, weak operation of cooling operation (so-called simple cooling operation) is performed. By the way, during the cooling / dehumidifying operation, if the temperature of the indoor heat exchanger does not reach the dew point, the room relative humidity only increases and the indoor relative humidity increases, which may cause discomfort.

  That is, the rate of change of latent heat is smaller than the rate of change of sensible heat by the indoor heat exchanger, and only sensible heat is exhibited, and the relative humidity rises to almost 100% as the room temperature is lowered. You will feel chilly. In recent years, air volume has been increased for the purpose of energy saving, but as the air volume increases, the temperature of the indoor heat exchanger increases and the dehumidification performance is sacrificed.

  For example, Patent Document 1 discloses a proposal for increasing the temperature of air blown from an indoor unit so as not to feel chills in the air during cooling and dehumidifying operations. In the invention described in Patent Document 1, a part of the indoor air sucked into the indoor unit is passed through the indoor heat exchanger to be cold air of 12 to 15 ° C. On the other hand, the remaining air bypasses the indoor heat exchanger, mixes with cool air cooled to 12 to 15 ° C. by the indoor heat exchanger in the mixing chamber before the air outlet, and blows out from the air outlet.

JP 2000-88327 A

  According to the invention described in Patent Document 1, the temperature of the blown air can be set to 20 to 25 ° C., and a temperature at which the feeling of cold air is not felt. However, the invention described in Patent Document 1 does not disclose a technique for increasing the amount of dehumidification when the damper for bypassing the indoor heat exchanger is opened or closed, or the timing for opening or closing the damper.

  Accordingly, an object of the present invention is to open and close the damper at an appropriate timing to raise the temperature of the blown air, and to improve the dehumidifying performance during cooling and dehumidifying operation to improve comfort.

In order to solve the above problems, the present invention is disposed on the air inlet side in an air passage connecting the housing having an air inlet and an air outlet, and the air inlet and the air outlet in the housing. Air having an indoor heat exchanger, an indoor fan disposed on the air outlet side in the air passage, and a refrigeration cycle including at least the indoor heat exchanger and a control means for controlling the indoor fan. In the conditioner, the raw gas introduction unit that brings the raw gas of indoor air and / or outdoor air to the indoor blower without passing through the indoor heat exchanger, and the control by the control means during the cooling cycle operation of the refrigeration cycle And a damper that opens and closes the raw gas introduction section, and the control means sets the rotation speed when the damper is in a closed state as a rotation speed mode of the indoor blower. 1. It has at least three rotation speed modes, ie, a rotation speed R2 (<R1) when the damper is in an open state and a rotation speed R3 (<R2) before the damper is opened, and a predetermined damper opening condition is satisfied. When the damper is changed from the closed state to the open state, the first step of changing the rotational speed of the indoor blower from the rotational speed R1 to the rotational speed R3, and the second step of maintaining the rotational speed R3 for a predetermined time. And a third step of opening the damper after the second step, and changing the rotational speed of the indoor blower from the rotational speed R3 to the rotational speed R2 when the damper reaches a predetermined open position. The fourth step is performed.

According to the onset bright, as the rotation speed mode of the indoor blower, damper rotational speed R1 of the closed state, the rotation number before the damper is a rotational speed R2 (<R1) and damper the open state to the open state R3 (<R2) at least three rotational speed modes are prepared, and when a predetermined damper opening condition is satisfied and the damper is opened from the closed state, the rotational speed of the indoor fan is changed from the rotational speed R1 to the rotational speed R3. The rotation speed R3 is maintained for a predetermined time and the damper is opened, and then the rotation speed of the indoor fan is changed from the rotation speed R3 to the rotation speed R2. The damper can be opened in the state.

  First, a basic embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing an internal structure of an indoor unit included in an air conditioner of the present invention, FIG. 2 is a block diagram showing a control system of the present invention, and FIGS. 3 and 4 show a first control operation example of the present invention. FIG. 5 and FIG. 6 are flowcharts showing a second control operation example and a humidity control zone according to the present invention. FIGS. 7 and 8 are third control operation examples according to the present invention. It is explanatory drawing which shows the flowchart and the dew point temperature control zone which show.

  The air conditioner of this invention is provided with the indoor unit 10 shown in FIG. The indoor unit 10 in this example has a wall-mounted housing (housing) 11, and the housing 11 includes a base plate 20 attached to a wall surface in the room and an exterior panel 30 supported by the base plate 20. include.

  In this example, the exterior panel 30 has a panel body 31 that covers from the bottom surface to the front surface, and a top panel 32 that covers the top surface, and an air outlet 311 is provided on the bottom surface side of the panel body 31. The upper panel 32 is a grill panel having an air inlet 321.

  The air outlet 311 is provided with an up-and-down air direction plate 312 and a diffuser plate 313 that is opened at the time of rapid heating or rapid cooling. Instead of the diffuser plate 313, two up-and-down air direction plates 312 may be used. .

  The air outlet 311 may be provided with left and right wind direction plates (not shown). An air filter (not shown) is provided on the inner surface side of the air inlet 321 of the upper panel 32. An air inlet may also be provided on the front side of the panel body 31.

  In the housing 11, an indoor heat exchanger 40 and an indoor blower (indoor fan) 50 are disposed in an air passage extending from the air inlet 321 of the upper panel 32 to the air outlet 311 of the panel body 31. The indoor heat exchanger 40 and the indoor blower 50 are supported between side plates (not shown) provided at both ends of the base plate 20. Usually, a cross flow fan is used for the indoor blower 50.

  The indoor heat exchanger 40 includes a first heat exchanger unit 41 disposed on the front surface side of the panel body 31 and a second heat exchanger disposed on the back surface side of the panel body 31 as divided heat exchanger units. At least two heat exchanger units of unit 42 are provided.

  The first heat exchanger unit 41 and the second heat exchanger unit 42 are combined in a lambda (Λ) shape and arranged around the air suction side of the indoor blower 50. As in this example, A third heat exchanger unit 43 may be further provided below the first heat exchanger unit 41.

  On the inner surface side of the panel body 31, a drain pan 314 that receives dew that drops from the first heat exchanger unit 41 and the third heat exchanger unit 43 is formed. On the other hand, the base plate 20 is provided with a blower guide plate 21 that forms a blower path from the indoor blower 50 to the air outlet 311 between the bottom surface of the drain pan 314, and the blower guide plate 21 is provided with the second heat A drain pan 22 for the exchanger unit 42 is provided.

  In this example, an electric dust collector 60 is provided in the first heat exchanger unit 41, and a console box 70 is provided on the front surface of the panel body 31. The console box 70 houses a light receiving element that receives an infrared remote control signal, for example, a circuit board on which a display for displaying an operation mode or room temperature is mounted.

  Although not shown, the housing 11 includes a room temperature sensor that detects the temperature (room temperature) of the room air, a humidity sensor that detects the relative humidity of the room air, and a heat exchanger temperature sensor that detects the temperature of the indoor heat exchanger 40. Provided. The room temperature sensor and the humidity sensor are preferably arranged on the air suction surface side of the indoor heat exchanger 40.

  In the present invention, in the cooling cycle operation including the weak cooling operation at the time of dehumidification, the dehumidification performance due to latent heat is enhanced and the temperature of the blown air during the cooling cycle operation is increased. An opening 80 that directly introduces air (sometimes referred to as raw gas) without heat exchange and a damper 91 for adjusting the opening ratio of the opening 80 are provided.

  In this example, the opening 80 is provided between the upper ends of the first heat exchanger unit 41 and the second heat exchanger unit 42. The damper 91 is a slide type and is driven by a motor 92 via a pinion-rack mechanism. A stepping motor is preferably used as the motor 92. Unlike this example, the damper 91 may be a rotary type.

  By opening the damper 91 and introducing the raw gas from the opening 80, the amount of air passing through the indoor heat exchanger 40 is relatively reduced and the passing wind speed is slowed. As a result, the temperature of the indoor heat exchanger 40 is reduced. Is maintained at a temperature lower than the dew point temperature of the room air, the difference between the dew point temperature of the room air and the heat exchange temperature of the indoor heat exchanger 40 is increased, and the dehumidification (latent heat) performance is improved. In addition, the temperature of the air blown out from the air outlet 311 is increased by the introduction of the raw gas, and the sensation of chill that has been a problem during the cooling / dehumidifying operation is solved.

  Depending on the temperature conditions, the temperature of the indoor heat exchanger 40 can be maintained at a temperature lower than the dew point temperature of the indoor air without changing the rotational speed of the indoor blower 50 or the rotational speed of the compressor. The temperature of the indoor heat exchanger 40 is set to a temperature lower than the dew point temperature of the indoor air by changing the rotation speed of the indoor blower 50 and / or the rotation speed of the compressor and the throttle degree of the expansion valve included in the refrigeration cycle. May be.

  On the other hand, by introducing the raw gas from the opening 80, it is possible to make it difficult for condensation to occur in the indoor blower 50. That is, dew condensation of the indoor blower occurs when air having a high dew point temperature comes into contact with the indoor blower cooled by the cold air from the heat exchanger. In the present invention, the raw gas introduced from the opening 80 is indoors. It is mixed with the cold air from the heat exchanger 40, the temperature of the raw gas is lowered, and the dew point temperature of the raw gas is lowered accordingly, so that condensation in the indoor blower 50 is less likely to occur.

  The opening 80 may be provided between the first heat exchanger unit 41 and the third heat exchanger unit 43, but the air cooled by the indoor heat exchanger 40 and the raw air introduced from the opening 80. In order to improve the mixing with gas (in this specification, this mixing is sometimes referred to as a premix), the opening 80 is most distant from the indoor blower 50 as shown in FIG. It is preferable to arrange at a distant position (in this example, between the upper ends of the first heat exchanger unit 41 and the second heat exchanger unit 42).

  Moreover, in FIG. 1, the flow direction of the raw gas which goes through the opening part 80 to the indoor air blower 50 is set to HG, and the flow direction of the cold air which goes to the indoor air blower 50 through the 1st heat exchanger unit 41 is set to CG1, 2nd heat. Assuming that the flow direction of the cold air flowing through the exchanger unit 42 toward the indoor blower 50 is CG2, the angle θ1 where HG and CG1 intersect and the angle θ2 where HG and CG2 intersect are preferably 30 degrees or more.

  According to this, since the raw gas is sandwiched between cold air and the angle at which the raw gas intersects is large, mixing of the raw gas and cold air is further promoted, and condensation of the indoor blower 50 can be more effectively prevented. it can.

  Next, the control system will be described with reference to FIG. The control system includes an indoor unit control unit 100 and an outdoor unit control unit 200. The indoor unit controller 100 receives signals from a remote controller, a room temperature sensor, a humidity sensor, a heat exchanger temperature sensor, and a damper position detection limit switch (all not shown).

  The indoor unit control unit 100 includes a remote control signal determination unit 110, an operation mode memory 120, an operation state determination unit 130, a set temperature memory 140, a room temperature memory 150, an indoor humidity memory 160, a room temperature-set temperature comparison unit 170, and a dew point temperature calculation unit. 180 and a damper state determination unit 190, which control the damper drive motor 92 and the indoor fan motor of the indoor blower 50 based on each input signal described above, and output a compressor control signal to the outdoor unit control unit 200.

  The outdoor unit control unit 200 includes an operation mode determination unit 210, a compressor control unit 220, and a four-way valve control unit 230. Based on the compressor control signal from the indoor unit control unit 100, the outdoor unit motor and the four-way valve control unit 230 Control the valve.

  Next, a first control operation example of the damper 91 that adjusts the aperture ratio of the opening 80 will be described with reference to FIGS. 3 and 4. In this first control operation example, the opening degree of the damper 91 is adjusted by the temperature difference (Tr−Ts) between the room temperature Tr and the set temperature Ts by the remote controller.

  In this case, for example, the temperature control zone shown in FIG. 4 is set. A to D are threshold values. As an example, A is 4 [K], B is 2 [K], C is 3.5 [K], and D is 1.5 [K] (K is Kelvin). The reason why C and D are shifted by 0.5 [K] from A and B is to prevent chattering.

  With reference to the flowchart of FIG. 3, when the operation is started, it is determined whether the operation is a heating operation or a cooling (dehumidification) operation (step ST31). If it is heating operation, the damper 91 is fully closed (step ST32). If it is a cooling operation, it is determined whether the blown air volume is automatically set (step ST33).

  If the blown air volume is automatically set, the room temperature Tr is monitored (step ST34A), and it is determined whether the temperature difference (Tr−Ts) between the room temperature Tr and the set temperature Ts is larger than A ((Tr−Ts)> A). (Step ST35A). As a result, if (Tr−Ts)> A, the sensible heat capacity is required for the indoor heat exchanger 40, and therefore the damper 91 is fully closed and the blown air volume is set to be a weak wind (step ST36A). ), The process returns to step ST34A (note that the inequality sign “>” may be replaced by an inequality sign with an equal sign “≧”. The same applies to the following description).

  If (Tr-Ts)> A is not satisfied, it is next determined whether (Tr-Ts)> B (step ST37A). As a result, if (Tr−Ts)> B, the damper 91 is opened halfway, the sensible heat / latent heat ratio of the indoor heat exchanger 40 is changed, and the amount of blown air is changed to a slight wind (step ST38A), and then step ST34A. Return to.

  If (Tr−Ts)> B is not satisfied, the damper 91 is fully opened to increase the latent heat capacity of the indoor heat exchanger 40, and the blowing air volume is set to be silent (step ST39A), and the process returns to step ST34A.

  In step ST33, when the blown air volume is not automatically set but manually set by the remote controller, steps ST34M to ST39M similar to steps ST34A to ST39A are executed. In this case, regardless of opening / closing of the damper 91, Let the blown air volume be the set air volume.

  In step ST38A (ST38M), ST39A (ST39M), when opening the damper 91, it is preferable to increase the rotational speed of the compressor according to the opening degree to maintain the cooling capacity.

  Next, a second control operation example of the damper 91 that adjusts the opening ratio of the opening 80 will be described with reference to FIGS. 5 and 6. In this second control operation example, the opening degree of the damper 91 is adjusted by the indoor humidity (relative humidity) RH. In this case, as shown in FIG. 6, threshold values are set at, for example, 70% and 60% humidity.

  Referring to the flowchart of FIG. 5, when the operation is started, it is determined whether the operation is a heating operation or a cooling (dehumidification) operation (step ST51). If it is heating operation, the damper 91 is fully closed (step ST52). If it is a cooling operation, the indoor humidity RH is monitored (step ST53), and it is determined whether RH> 70% (step ST54).

  As a result, if RH> 70%, the damper 91 is fully closed (step ST55), and the process returns to step ST53. If RH> 70% is not satisfied, it is next determined whether RH> 60% (step ST56). As a result, if RH> 60%, the damper 91 is half opened (step ST57), and the process returns to step ST53. Unless RH> 60%, the damper 91 is fully opened (step ST58), and the process returns to step ST53.

  In order to simplify the control, for example, the threshold value may be 60% only, and may be fully closed when RH> 60%, and fully open when RH> 60%. Thus, the present invention includes a case where there are only two states of fully closed and fully open. That is, the aperture ratio is 0% when fully closed and the aperture ratio is 100% when fully open. This is also included in the present invention as one aspect of adjusting the aperture ratio of the opening 80.

  Next, a third control operation example of the damper 91 that adjusts the opening ratio of the opening 80 will be described with reference to FIGS. 7 and 8. In this third control operation example, the opening degree of the damper 91 is adjusted by the temperature difference (Tw−Te) between the dew point temperature Tw of the indoor air and the heat exchanger temperature Te of the indoor heat exchanger 40. The temperature control zone used in this case is shown in FIG. The thresholds A to D may be the same as in FIG. 4, and these thresholds A to D may be determined empirically.

  Referring to the flowchart of FIG. 7, when the operation is started, it is determined whether the operation is a heating operation or a cooling (dehumidification) operation (step ST71). If it is heating operation, the damper 91 is fully closed (step ST72). If it is a cooling operation, the room temperature Tr and the humidity RH are monitored (step ST73), and the dew point temperature Tw of the room air is calculated (step ST74).

  Next, the heat exchanger temperature Te is monitored (step ST75), and whether the temperature difference (Tw−Te) between the dew point temperature Tw and the heat exchanger temperature Te is larger than A ((Tw−Te)> A). Judgment is made (step ST76). As a result, if (Tw−Te)> A, the damper 91 is fully closed (step ST77), and the process returns to step ST73.

  If (Tw−Te)> A is not satisfied, it is next determined whether (Tw−Te)> B (step ST78). As a result, if (Tw−Te)> B, the damper 91 is opened halfway (step ST79), and the process returns to step ST73. If (Tw−Te)> B is not satisfied, the damper 91 is fully opened (step ST80), and the process returns to step ST73.

  As described above, according to the present invention, the opening ratio of the opening 80 for introducing raw gas can be adjusted by the damper 91, and the sensible heat / latent heat ratio of the indoor heat exchanger 40 can be arbitrarily changed. Thus, the dehumidifying performance during cooling can be enhanced, and the relative humidity of the indoor environment can be lowered. Moreover, since the temperature of the blown air rises due to the introduction of the raw gas, the sensation of chilling that has been a problem during the cooling cycle operation is solved.

  Further, since the relative humidity is lowered and the comfort at the same set temperature is improved, that is, the set temperature can be increased to obtain the same comfort, the power consumption can be reduced. In addition, the raw gas introduced from the opening 80 and the cold air passing through the indoor heat exchanger 40 are mixed in front of the indoor blower 50, the temperature of the raw gas is lowered, and the dew point temperature of the raw gas is accordingly reduced. Therefore, condensation in the indoor blower 50 is less likely to occur.

  In addition, when the indoor humidity is high and indoor conditions in which condensation is likely to occur in the indoor blower 50, the condensation on the indoor blower 50 can be prevented by closing the damper 91. Further, when the difference between the room temperature and the set temperature is large and the sensible heat capacity is required, the shortage of the sensible heat capacity can be solved by closing the damper 91.

  Next, another embodiment of the raw gas introducing means for guiding the raw gas (indoor air or outdoor air (outside air)) into the housing 10 without passing through the indoor heat exchanger 40 will be described with reference to FIGS.

  In this other embodiment, ducts 80D1 and 80D2 shown in FIGS. 9 and 10 are used. When there is no need to distinguish between the two ducts 80D1 and 80D2, they are collectively referred to as a duct 80D. 9 and 10 are exploded perspective views of the ducts 80D1 and 80D2.

  A duct 80 </ b> D <b> 1 illustrated in FIG. 9 includes a long rectangular tube 81 having a trapezoidal cross section, for example, and a damper 82 disposed in the rectangular tube 81. On the upper surface of the rectangular cylinder 81, air inlets 811 for introducing the raw gas into the duct are formed in a plurality of slit shapes, for example.

  Further, on the bottom surface of the rectangular cylinder 81, air outlets 812 for leading the raw gas in the duct toward the indoor blower 50 are formed, for example, as a plurality of slit shapes. Both ends of the rectangular cylinder 81 are closed. Note that the air inlet 811 and the air outlet 812 may be provided on different surfaces of the rectangular cylinder 81.

  In this example, the damper 82 is composed of a long shutter plate that is slidably disposed on the bottom surface side in the rectangular cylinder 81, and a plurality of slit holes 821 corresponding to the air outlet 812 are formed in this. ing.

  The damper 82 is moved between a fully open position where the air outlet 812 and the slit hole 821 are matched by a driving means such as a motor (not shown) and a fully closed position where the slit hole 821 is shifted with respect to the air outlet 812. It is driven reciprocally. The sliding direction may be either the length direction or the width direction of the damper 82.

  The damper 82 is preferably disposed on the air outlet port 812 side so that air (cold air) does not flow backward in the duct 80D1, but may be provided on the air inlet port 811 side. .

  A duct 80 </ b> D <b> 2 shown in FIG. 10 includes a long rectangular tube 83 having a trapezoidal cross section, for example, whose upper surface is covered with a lid plate 84, and a damper 85 disposed in the rectangular tube 83. In this duct 80D2, an air inlet 831 is formed on one end surface of the rectangular tube 83, and an air outlet 832 is formed in a plurality of slit shapes on one side surface facing in the width direction of the rectangular tube 83. Yes.

  The damper 85 is a long shutter plate that is slidably disposed on the side surface on the air outlet side in the rectangular tube 83, and a plurality of slit holes 851 corresponding to the air outlet 832 are formed in the damper 85. Yes. The damper 85 is moved between a fully open position where the air outlet 832 and the slit hole 851 match each other and a fully closed position where the slit hole 821 is shifted with respect to the air outlet 832 by a driving unit such as a motor (not shown). It is driven reciprocally.

  Also in this duct 80D2, in order to prevent air (cold air) from flowing backward in the duct and causing condensation, the damper 85 is preferably disposed on the air outlet 832 side, but on the air inlet 831 side. For example, a flap valve-like damper may be provided. In addition, the air outlet 832 may be provided on the bottom surface of the rectangular tube 83 similarly to the duct 80D1.

  In this duct 80D2, the indoor air is sucked into the duct with the operation of the indoor blower 50 by causing the air inlet 831 formed on one end surface to face the side surface of the housing 10, for example. In the case of a model having a ventilation fan 51 for taking air into the room, outdoor air can be introduced into the duct from the ventilation fan 51.

  For example, as shown in FIG. 11, the duct 80 </ b> D has a triangular cross section along the inner side of the upper end connection portion between the first indoor heat exchanger 41 on the front side and the second indoor heat exchanger 42 on the rear side. Can be arranged. Also, as shown in FIG. 12, a gap is provided between the upper ends of the first indoor heat exchanger 41 and the second indoor heat exchanger 42, and a duct 80D is provided in the gap (a portion corresponding to the opening 80 in FIG. 1). Can also be arranged.

  As illustrated in FIG. 13, the duct 80 </ b> D may be disposed along the outside of the upper end connection portion between the first indoor heat exchanger 41 and the second indoor heat exchanger 42. The duct 80D can also be provided in the indoor heat exchanger. In that case, as shown in FIG. 14, for example, the duct 80D may be embedded so as to penetrate the fin group of the first indoor heat exchanger 41 on the front side. Alternatively, as shown in FIG. 15, it may be embedded in a part of the front side of the fin group of the first indoor heat exchanger 41.

  11, duct 80D2 shown in FIG. 10 is preferably used for duct 80D, and any of ducts 80D1 and 80D2 may be used in the examples of FIGS. In any case, the length of the duct 80D is preferably ½ or more of the width in the longitudinal direction of the indoor heat exchanger so that the introduced air can be evenly sent to the indoor fan 50. .

  Further, the damper 82 of the duct 80D1 and the damper 85 of the duct 80D2 are driven and controlled by the control means similarly to the damper 91 of FIG. In the case of the example of FIG. 13 and the example of FIG. 15, the air derived from the duct 80 </ b> D passes through the heat exchanger. It may be.

  Next, conditions for opening and closing the damper 91 (including the dampers 82 and 85) will be described. As described above, the damper 91 is controlled to open and close using the room temperature, humidity, dew point temperature, and the like as parameters. However, the damper 91 is opened in a state where the temperature difference between the actual room temperature Tr and the set temperature Ts by the remote controller is large. Then, the time required for the sensible heat capacity to fall to the set temperature Ts becomes longer, which may cause discomfort to the user.

  Therefore, in the present invention, the temperature zone shown in FIG. 16 is set as an example, and the damper 91 is opened when the temperature difference between the room temperature Tr and the set temperature Ts becomes small. This temperature zone is for controlling the rotation speed of the compressor. The left side of FIG. 16 is a temperature zone applied when the room temperature decreases, and the right side is a temperature applied when the room temperature increases. It is a zone. In order to prevent chattering, the temperature threshold is different between when the room temperature is lowered and when the room temperature is raised.

  The values in parentheses are temperature thresholds when the room temperature rises. When the room temperature Tr is Ts + 1.0 ° C or higher (Ts + 2.0 ° C or higher), the X zone, Ts + 1.0 ° C (Ts + 2.0 ° C) to Ts-1.5 ° C Between Ts-0.5 ° C) is F zone, and between Ts-1.5 ° C (Ts-0.5 ° C) to Ts-2.5 ° C (Ts-1.5 ° C) is G zone, Ts- The temperature of 2.5 ° C. (Ts−1.5 ° C.) or less is in the Y zone, and the rotational speed of the compressor is decreased in the order of X → F → G, and the compressor is stopped in the Y zone.

  In this example, when the room temperature Tr is in the X zone, for example, even if the humidity is high and dehumidification is required, the cooling operation is performed with the damper 91 closed, and the room temperature Tr decreases and the X The damper 91 is opened when the zone enters the F zone, that is, when the temperature difference between the room temperature Tr and the set temperature Ts becomes 1.0 ° C. or less.

  Thereby, when the temperature difference between the room temperature Tr and the set temperature Ts is large, it is possible to shorten the arrival time until the set temperature Ts is reached. In a temperature setting priority mode called a powerful mode set by the remote controller, the damper may not be opened until the powerful mode is canceled.

  The damper open state is maintained while the room temperature Tr is in the F zone, the G zone, and the Y zone. On the other hand, when the room temperature Tr starts to rise and passes through the F zone and enters the X zone, that is, when the temperature difference between the room temperature Tr and the set temperature Ts becomes 2.0 ° C. or more, the damper 91 is closed.

  Further, in the present invention, for example, the following measures are taken in order to prevent the chattering of the damper open / close due to the fluctuation of the humidity detection value. As the damper opening condition, the indoor humidity is monitored. For example, when the humidity becomes 65% or less, the damper 91 is opened when the humidity 65% or less is detected continuously three times every minute thereafter. Moreover, once opened, the open state is maintained unconditionally for a predetermined time (for example, 5 minutes).

  On the other hand, as the damper closing condition, the indoor humidity is monitored. For example, when the humidity becomes 75% or more, the damper 91 is closed when 75% or more of the humidity is detected three times continuously every minute thereafter. ing.

  Since the original purpose of the premix is to increase the dehumidifying capacity, once the damper is opened, it will not close early even if the damper closing conditions are in place. Is preferably increased. On the other hand, when the damper is opened from the closed state, it is preferable that the damper is opened as soon as the damper opening condition is satisfied in order to increase the amount of dehumidification as much as possible.

  Therefore, as one method of achieving both the prevention of chattering of opening / closing of the damper and the increase of the dehumidifying amount, when the damper is opened to closed, for example, for 6 minutes (the above three times) (Confirmation time of +3 minutes) If the damper is opened from the closed state, and the damper is opened from the closed state, the closed state is maintained for 4 minutes (the above three confirmation times + 1 minute) after the opening condition is satisfied. It is preferable to maintain a time difference between the case of opening → closed and the case of closing → opening.

  Further, when the damper 91 is opened, the ventilation resistance is lowered, so that the rotational speed of the indoor blower 50 is increased, the air volume is suddenly increased, and the noise is increased accordingly. In order to prevent this, the present invention takes the following measures, which will be described with reference to the timing chart of FIG.

  First, as the rotational speed control mode of the indoor blower 50, the normal rotational speed R1 when the damper is closed, the rotational speed R2 when the damper is opened, and the rotational speed R3 before opening the damper (both are rpm) are R1> R2> R3. For example, R3 is set to about R2-60 rpm.

  When the damper is closed and operated at the normal rotation speed R1, the damper 91 is not opened immediately even if the condition for opening the damper is satisfied. First, when the damper is opened from the normal rotation speed R1 to the rotation speed of the indoor blower 50 The speed is reduced to the previous rotational speed R3, for example, masked for 3 seconds (ignoring the damper open signal).

  After 3 seconds, the damper 91 is opened, and after confirming that the damper 91 is opened, the rotational speed of the indoor blower 50 is changed from the rotational speed R3 before the damper is opened to the rotational speed R2 when the damper is opened. increase. By executing this control, it is possible to prevent an increase in air volume and noise when the damper 91 is opened.

  Next, the control performed in the present invention when the damper 91 has failed will be described. Referring again to FIG. 1, the damper 91 is driven by a stepping motor 92, the open position is detected by a limit switch (not shown), and the closed position is monitored by the number of rotation pulses applied to the stepping motor 92.

  The failure of the damper means that the damper 91 does not open, does not close, or is caught in something and stopped in the middle. If the cooling operation is continued with the damper 91 particularly open, Condensation is likely to occur inside.

  Therefore, when the damper 91 breaks down, it is conceivable to stop the operation. However, since the damper 91, which is a raw gas introduction means for the air conditioner, is an additional function, the cooling operation is stopped due to the failure. This makes it difficult to adjust the indoor environment, which inconveniences the user. Therefore, in the present invention, it is a principle that the cooling operation is continued even when a failure of the damper 91 is detected.

  Moreover, when the damper 91 is in the open state, the temperature of the indoor heat exchanger 40 tends to decrease, and the heat exchanger may freeze. Once icing occurs, the heat exchanger's condensate may adhere sequentially and freeze. This problem is likely to occur particularly in the case of an air conditioner having a large cooling capacity (for example, a capacity of about 5 kW or 6.3 kW).

  Therefore, in the present invention, the rotational speed of the compressor is changed between when the damper is closed and when the damper is opened, regardless of whether or not the damper 91 has failed. For example, when the damper is open, the rotational speed of the compressor is reduced by about 10% from the rotational speed when the damper is closed, so that the temperature of the heat exchanger does not drop too much. Further, when the damper 91 fails, the cooling operation is performed at the rotation speed of the compressor when the damper is opened.

  This control will be described with reference to the flowchart of FIG. FIG. 18A is a flowchart when the damper closing operation is changed to the damper opening operation, and the damper 91 is opened under the damper opening condition. At this time, if the damper 91 is opened without any trouble, the rotation of the compressor is performed. The number is made lower than the number of revolutions when the damper is closed, and the operation shifts to the damper opening operation.

  However, when the damper opening is not confirmed, for example, an LED (not shown) in the console box 70 is turned on or blinked to display an error, and the operation proceeds to the damper opening operation. That is, the rotational speed of the compressor is set lower than the rotational speed when the damper is closed.

  FIG. 18B is a flowchart when the damper opening operation is changed to the damper closing operation. When the damper closing condition is satisfied, the damper 91 is closed. If the damper 91 is closed without any trouble at that time, the rotational speed of the compressor is changed. Is set higher than the number of revolutions when the damper is opened, and the operation shifts to the damper closing operation.

  However, if it is not confirmed that the damper is closed, for example, an LED (not shown) in the console box 70 is turned on or blinked to display an error, and the rotational speed of the compressor is made lower than the rotational speed when the damper is closed. The damper is opened.

  In this way, when the damper fails, the rotation speed of the compressor is reduced to lower the cooling capacity, thereby making the interior of the indoor unit less susceptible to condensation. In order to prevent the temperature of the heat exchanger from being lowered too much, the rotational speed of the compressor is decreased, the rotational speed of the indoor blower 50 is increased, and preferably the rotational speed of the outdoor blower is decreased.

  For example, in the case of an air conditioner of 2.8 kW class with a relatively low cooling capacity, the temperature of the indoor heat exchanger does not drop significantly even if the damper is opened. It is not necessary to change the rotational speed of the compressor, and the rotational speed of the compressor may be maintained when the damper is open and when the damper is closed.

  In the present invention, raw gas is introduced into the housing 10 from the opening 80 in FIG. 1 or the duct 80D shown in FIGS. 9 and 10, but the raw gas (warm air) does not cause condensation in the indoor blower 50. Therefore, it is necessary to sufficiently cool the raw gas with air (cold air) that has passed through the indoor heat exchanger 40 on the upstream side of the indoor blower 50. In the description here, the raw gas introduction portions 80 and 80D including the opening 80 and the duct 80D are used.

  Therefore, in the present invention, the raw gas is effectively mixed with the air that has passed through the indoor heat exchanger 40 and sufficiently cooled in relation to the refrigerant flow path that flows through the indoor heat exchanger 40. The basic configuration is that the raw gas introduction sections 80 and 80D are arranged on the downstream side of the refrigerant flow path, and the refrigerant is flowed from the upstream side with respect to the air flow direction in the refrigerant flow path. Moreover, the temperature of a refrigerant | coolant can be lowered | hung by making a refrigerant circuit branch into plurality and lowering | hanging the pressure of a refrigerant | coolant. One example will be described with reference to FIG.

  FIG. 19A is a schematic diagram showing a refrigerant flow path (refrigerant pipe) of the indoor heat exchanger 40. The first indoor heat exchanger 41 and the second indoor heat exchanger 42 are opened and closed for reheat dehumidification. The valve 45 and the capillary tube 46 are connected via a parallel circuit, and the refrigerant flows from the second indoor heat exchanger 42 to the first indoor heat exchanger 41, but the on-off valve 45 and the capillary tube 46 are omitted. Also good.

  As shown in FIG. 19 (a), when the raw gas introduction sections 80 and 80D are arranged between the upper ends of the first indoor heat exchanger 41 and the second indoor heat exchanger 42, each indoor heat exchanger 41, 42 has, for example, three rows of refrigerant channels, PA3 and PB3 are the refrigerant channels closest to the raw gas introduction sections 80 and 80D, PA2 and PB2 are the refrigerant channels in the outer rows, and further outside If the refrigerant flow paths in this row are PA1 and PB1, in the second indoor heat exchanger 42, the refrigerant flows from the refrigerant flow path PB1 toward the refrigerant flow path PB3. Similarly, in the first indoor heat exchanger 41, the refrigerant flows. The refrigerant is caused to flow from the flow path PA1 side toward the refrigerant flow path PA3.

  Thus, with respect to the air flow direction, the refrigerant flow paths PA1 and PB1 are on the upstream side, and the refrigerant flow paths PA3 and PB3 closest to the raw gas introduction portions 80 and 80D are on the downstream side. In general, since the pressure of the refrigerant gradually decreases due to a loss due to the flow path resistance of the pipe, the temperature of the refrigerant decreases as it goes to the outlet side of the refrigerant flow path.

  Therefore, since the temperature of the air passing through the heat exchanger decreases in order from the upstream side toward the downstream side, the refrigerant flow paths PA3 and PB3 closest to the raw gas introduction portions 80 and 80D are set to the downstream side as described above. Thus, the raw gas introduced into the housing 10 can be sufficiently cooled to the extent that condensation does not occur before reaching the indoor blower 50.

  More preferably, as shown in FIG. 19 (b), one refrigerant flow path connecting the downstream refrigerant flow paths PA3 and PB3 of the indoor heat exchangers 41 and 42 and straddling the raw gas introduction sections 80 and 80D. It is good to do. According to this, since the introduced raw gas is cooled substantially uniformly by the downstream refrigerant flow path PA3 on the indoor heat exchanger 41 side and the downstream refrigerant flow path PB3 on the indoor heat exchanger 42 side, The variation of can be reduced. In addition, even if foreign matters are mixed in other refrigerant flow paths and the balance of the refrigerant flow rate is lost, cooling is performed by one refrigerant flow path, so that variations in cooling temperature can be further reduced.

  Further, as shown in FIG. 20 (a), the upstream refrigerant flow path PA1 on the indoor heat exchanger 41 side and the downstream refrigerant flow path on the indoor heat exchanger 42 side in a portion straddling the raw gas introduction sections 80 and 80D. You may make it connect with PB3.

  In addition, as shown in FIG. 20B, when the raw gas introduction sections 80 and 80D are embedded in, for example, the fin group of the indoor heat exchanger 41 and the refrigerant flow path in the vicinity thereof is configured with a plurality of paths, By disposing the refrigerant outlet side of each path in the raw gas introduction sections 80 and 80D, the introduced raw gas can be sent into the room without being cooled more than necessary, and the room temperature is not excessively lowered. That's it.

Sectional drawing which shows the internal structure of the indoor unit with which the air conditioner of this invention is provided. The block diagram which shows the control system of this invention. The flowchart which shows the 1st control operation example of this invention. Explanatory drawing which shows the temperature control zone | band in the said 1st control operation example. The flowchart which shows the 2nd control operation example of this invention. Explanatory drawing which shows the temperature control zone | band in the said 2nd control operation example. The flowchart which shows the 3rd control operation example of this invention. Explanatory drawing which shows the temperature control zone | band in the said 3rd control operation example. The disassembled perspective view which shows the 1st example of the duct for raw gas introduction. The disassembled perspective view which shows the 2nd example of the duct for raw gas introduction. The typical sectional view showing the 1st example of arrangement of the above-mentioned duct in a housing. The typical sectional view showing the 2nd example of arrangement of the above-mentioned duct in a housing. The typical sectional view showing the 3rd example of arrangement of the above-mentioned duct in a housing. The typical sectional view showing the 4th example of arrangement of the above-mentioned duct in a housing. The typical sectional view showing the 5th example of arrangement of the above-mentioned duct in a housing. Explanatory drawing which shows the temperature zone for demonstrating the opening / closing conditions of a damper. The timing chart for operation | movement explanation at the time of opening a damper. The flowchart for demonstrating the operation mode at the time of a damper failure. The schematic diagram which shows the refrigerant | coolant flow path of the heat exchanger which cools raw gas effectively. The schematic diagram which shows the other refrigerant | coolant flow path of the heat exchanger which cools raw gas effectively.

DESCRIPTION OF SYMBOLS 10 Indoor unit 11 Housing 20 Base plate 21 Blower guide plate 22 Drain pan 30 Exterior panel 31 Panel main body 311 Air blower outlet 312 Vertical wind direction plate 314 Drain pan 32 Top panel 321 Air inlet 40 Indoor heat exchanger 41 1st heat exchanger unit 42 Second heat exchanger unit 43 Third heat exchanger unit 50 Indoor fan 80 Opening 80D (80D1, 80D2) Duct 82, 85, 91 Damper 92 Damper drive motor 100 Indoor unit control unit 200 Outdoor unit control unit

Claims (1)

A housing having an air inlet and an air outlet, an indoor heat exchanger disposed on the air inlet side in an air passage connecting the air inlet and the air outlet in the housing, and the air passage In an air conditioner comprising an indoor blower arranged on the air outlet side, a refrigeration cycle including at least the indoor heat exchanger, and a control means for controlling the indoor blower.
A raw gas introduction section for bringing the raw gas of indoor air and / or outdoor air to the indoor blower without passing through the indoor heat exchanger, and the raw gas under the control of the control means during the cooling cycle operation of the refrigeration cycle Including a damper for opening and closing the gas inlet,
The control means sets the rotational speed mode of the indoor blower as a rotational speed R1 when the damper is closed, a rotational speed R2 when the damper is open (<R1), and a rotation before the damper is opened. Comprising at least three rotational speed modes of number R3 (<R2);
When the predetermined damper opening condition is satisfied and the damper is changed from the closed state to the open state, a first step of changing the rotational speed of the indoor fan from the rotational speed R1 to the rotational speed R3, and the rotational speed R3, A second step for maintaining a predetermined time; a third step for opening the damper after the second step; and a rotation speed of the indoor blower from the rotation speed R3 when the damper reaches a predetermined open position. An air conditioner that performs the fourth step of changing to the rotational speed R2.

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