JP6237755B2 - Indoor unit - Google Patents

Description

  The present invention relates to an indoor unit. More specifically, the present invention relates to an indoor unit that corrects a measured value of a suction temperature sensor in accordance with a flap posture.

  Conventionally, in an indoor unit of an air conditioner, a suction temperature sensor is provided in the vicinity of the suction port of the indoor unit, and the temperature measured by the suction temperature sensor (room temperature) and a set temperature or a target temperature (hereinafter, “target temperature”). Based on the temperature difference from the above, the cooling capacity or the heating capacity is controlled so that the room temperature approaches the target temperature.

  However, due to the influence of the air blown out from the indoor unit, specifically, when the flap position is controlled so that the air is blown downward, a part of the air blown out from the indoor unit is short-circuited. In consideration of the fact that the suction temperature sensor cannot accurately measure the room temperature by reaching the vicinity of the suction temperature sensor, it has been proposed to correct the measurement value of the suction temperature sensor (for example, Patent Document 1).

  In the air conditioner described in Patent Document 1, when the air volume blown out from the air outlet is large, in consideration of the fact that a short circuit is unlikely to occur, not only the posture of the flap, that is, the air direction, The measured value of the suction temperature sensor is corrected in consideration of the size.

JP 2014-55730 A

By the way, at the initial stage of operation, for example, it is conceivable to increase the wind speed of the air blown from the air outlet and supply the conditioned air to every corner of the air-conditioned room in order to quickly and uniformly bring the room temperature close to the target temperature. For example, in a four-way blowout ceiling embedded indoor unit, a mode in which a cycle consisting of the following first to fourth steps is repeated a predetermined number of times until the room temperature reaches a target temperature (hereinafter, this operation mode is referred to as “circulation airflow mode”). Is considered to be executed.
1st step: While controlling the attitude | position of a pair of opposing flap so that a horizontal air current may be blown off, air is not blown off substantially from the blower outlet in which the attitude | position of the said other pair of opposing flap is arrange | positioned In this way, the wind speed of the horizontal airflow is increased.
Second step: The posture is controlled so that the downward airflow is blown out of all the flaps of the four outlets, and the air is blown out.
Third step: controlling the flap posture of the outlet that blows out the horizontal airflow in the first step so that air is not substantially blown out, and controlling the remaining flap posture so that the horizontal airflow is blown out Increase the wind speed of the horizontal airflow.
Fourth step: The posture is controlled so that the downward airflow is blown out of all the flaps of the four outlets, and the air is blown out.

By adopting the circulating airflow mode, the room temperature of the air-conditioned room can be brought closer to the target temperature faster than the conventional indoor unit, but it is assumed that the following problems may occur.
That is, in the circulating airflow mode, the flap posture needs to be changed frequently, but the flap posture is changed (change from a posture that generates a downward airflow to another posture, or a downward airflow from a certain posture). When a command to change the posture to be generated) is issued from the control unit, a command to correct the measured value of the suction temperature sensor is also issued in accordance with the command, so the suction temperature after correction changes immediately. In, the posture of the flap cannot change immediately. In other words, the suction temperature is corrected immediately, even though it takes time until the short circuit is affected, or the short circuit is eliminated, so when the flap attitude change command is issued. There may occur a phenomenon in which the corrected suction temperature rapidly increases or decreases in a short time (hereinafter, this phenomenon is also referred to as “hunting”).

  FIG. 5 is an explanatory diagram showing the behavior of the correction temperature when the indoor unit is operated in the circulating airflow mode described above during heating in a four-way blowout ceiling embedded indoor unit employing a conventional correction method. In FIG. 4, the suction temperature, the correction temperature, and the room temperature from the first step to the third step in the circulating airflow mode are shown as time passes.

  In FIG. 5, at the time of switching from the first step to the second step indicated by A, a command for correcting the measured value of the suction temperature sensor is issued simultaneously with a command for changing the posture of the flap. Although the correction temperature drops rapidly, the flap posture cannot be changed immediately, and it takes time until the short circuit is affected. Similarly, in FIG. 5, when switching from the second step to the third step indicated by B, a command for correcting the measured value of the suction temperature sensor is issued simultaneously with a command for changing the posture of the flap. The correction temperature rapidly increases in accordance with the correction command, but the flap posture cannot be changed immediately, and it takes time until the influence of the short circuit is eliminated. As described above, when the indoor unit adopting the conventional correction method is operated so as to periodically change the flap posture, the hunting in which the correction temperature rapidly rises or falls when the flap posture is changed occurs. End up.

  Usually, since the rotation speed of the compressor is controlled based on the corrected suction temperature value, the compressor rotation speed is frequently switched by the hunting of the corrected suction temperature, thereby improving the reliability of the compressor. There is a risk of hindrance. Specifically, for example, the life of the compressor may be reduced, or the outlet temperature may change due to a sudden change in the refrigerant temperature of the indoor unit.

  This invention is made | formed in view of such a situation, and it aims at providing the indoor unit which can avoid that hunting arises in the suction | inhalation temperature after correction | amendment.

The indoor unit of the present invention is
(1) An indoor unit including a suction temperature sensor and a control unit that corrects a measurement value of the suction temperature sensor based on a posture of a flap.
The control unit performs first flap temperature correction based on the first suction temperature correction based on the flap posture and second suction temperature correction based on the average value of the suction temperature after the first suction temperature correction. Select according to the indoor unit operation mode.

  In the indoor unit of the present invention, since the type of suction temperature correction can be selected according to the operation mode of the indoor unit including the flap posture control, the operation mode with frequent flap posture change that is likely to cause hunting. When it is adopted, it is possible to avoid the occurrence of hunting by selecting the second suction temperature correction and setting the corrected average value of the suction temperature to a value that is compared with the target temperature. By using the average value, even if hunting occurs in the suction temperature after correction by the first suction temperature correction, which is normal temperature correction, the influence of this hunting can be substantially eliminated.

(2) In the indoor unit of (1), the correction of the measured value of the suction temperature sensor may be performed when the flap posture is the flap posture closest to the suction port of the indoor unit. In this case, a short circuit to the suction port of the blown air is likely to occur when the flap posture is closest to the suction port of the indoor unit, and in such a case, by correcting the measured value of the suction temperature sensor, The temperature can be accurately detected.

(3) In the indoor unit of (1) or (2), the second suction temperature correction may be selected in an operation mode in which the flap posture is periodically switched. In this case, in the operation mode in which the flap posture is periodically switched, the flap posture is frequently changed. Therefore, by using the average value, the suction after the correction by the first suction temperature correction which is the normal temperature correction is used. Even if hunting occurs in the temperature, the influence of this hunting can be substantially eliminated.

(4) In the indoor units of (1) to (3), the second suction temperature correction may be a correction based on a moving average value of the suction temperature after the first suction temperature correction. In this case, by using the moving average value, even if hunting occurs in the suction temperature after correction by the first suction temperature correction, which is normal temperature correction, the influence of this hunting can be substantially eliminated.

(5) In the indoor units of (1) to (4), the indoor unit can be a ceiling-suspended or ceiling-buried indoor unit that blows out in four directions. In this case, in a ceiling-suspended or ceiling-buried indoor unit with four-way blowing, the posture of the flap is frequently changed. For example, the effect of the circulating airflow mode is expected. It is beneficial to be able to select either the first suction temperature correction or the second suction temperature correction to avoid hunting.

  According to the indoor unit of the present invention, it is possible to avoid the occurrence of hunting at the corrected suction temperature.

It is a perspective explanatory view of one embodiment of the indoor unit of the present invention. It is a section explanatory view of the indoor unit shown in FIG. It is a figure explaining the state of blowing air when employ | adopting circulating airflow operation mode in the indoor unit of 4 way blowing. It is a figure explaining the example of the 1st correction temperature when the circulating air current operation mode is adopted, and the 2nd correction temperature. It is a figure explaining the behavior of the correction temperature in the conventional correction method.

Hereinafter, embodiments of an indoor unit of the present invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited to these illustrations, is shown by the claim, and intends that all the changes within the meaning and range equivalent to the claim are included.
FIG. 1 is a perspective explanatory view of an indoor unit 1 according to an embodiment of the present invention, and FIG. 2 is a cross-sectional explanatory view of the indoor unit 1 shown in FIG.

  The indoor unit 1 is a ceiling-embedded indoor unit, and includes a casing 2 that houses various elements such as an indoor fan and a heat exchanger described later, and a decorative panel 3. The casing 2 is formed of a box-like body having an open lower end surface, and is disposed in an opening formed in the ceiling C as shown in FIG. The decorative panel 3 is formed of a quadrangular plate, and a suction port 4 for sucking air in the air-conditioned room is formed at the center. In addition, an elongated rectangular air outlet 5 that blows out conditioned air into the air-conditioned room is formed around the inlet 4 so as to extend along each side of the decorative panel 3.

  Each air outlet 5 is provided with a flap 5a that adjusts the direction of the conditioned air blown from the air outlet 5 into the air-conditioned room. The flap 5a can be rotated around an axis along the longitudinal direction of the outlet 5. The flap 5a can be rotated by a motor (not shown). The flap 5a has a size and shape that can substantially close the air outlet 5 as shown in the flap 5a on the left side of FIG. By rotating the flap 5a about the axis, the wind direction of the conditioned air blown out from the blowout port 5 can be made substantially horizontal (horizontal airflow) or almost downward (downward airflow). The left flap 5a in FIG. 2 is in a posture to generate a downward airflow, and the right flap 5a is in a posture to generate a horizontal airflow.

  A suction grill 6 and a filter 7 for removing dust in the indoor air sucked from the suction port 4 are arranged in this order in the suction port 4 of the decorative panel 3 from the indoor side.

  Inside the casing 2, the air in the air-conditioned room is sucked from the suction port 4 of the decorative panel 3, and after heat exchange is performed on the air, the indoor fan 8 that blows conditioned air into the air-conditioned room from the outlet 5 of the decorative panel 3. And the heat exchanger 9 arrange | positioned so that the said indoor fan 8 may be enclosed. The indoor fan 8 has a motor 10 and an impeller 11. Further, a control unit P for controlling the opening / closing of the air outlet 5 by the rotation of the flap 5 a and the operation of the indoor fan 8 is disposed in the casing 2. The control unit P further has a function of selecting the type of suction temperature correction described later according to the operation mode of the indoor unit including the posture control of the flap 5a.

  The heat exchanger 9 is a cross fin tube type heat exchanger formed by being bent so as to surround the indoor fan 8. Below the heat exchanger 9, the heat exchanger 9 is in the air where heat is exchanged by the heat exchanger 9. A drain pan 12 is provided for receiving drainage generated by the condensation of water.

  In the drain pan 12, a suction hole 13 corresponding to the suction port 4 of the decorative panel 3 and a blowout hole 14 corresponding to the blowout port 5 of the decorative panel 3 are formed. A bell mouth 15 for guiding air sucked from the suction port 4 of the decorative panel 3 to the impeller 11 of the indoor fan 8 is attached to the inner edge of the suction hole 13. A suction temperature sensor 16 for detecting the temperature of air sucked from the suction port 8 of the decorative panel 7 is provided adjacent to the control unit P.

  In the present embodiment, during the heating operation, the automatic air volume operation is performed in which the rotation speed of the motor 14 of the indoor fan 12 is changed based on the temperature difference between the target temperature and the suction temperature detected by the suction temperature sensor 16. And when performing this air volume automatic driving | operation, it measured in order not to employ | adopt the suction temperature detected by the said suction temperature sensor 16 as it is, but to eliminate or reduce the influence of the short circuit of the conditioned air which was blown out. The corrected suction temperature is used to correct the suction temperature. The correction method is not particularly limited in the present invention, and a conventional correction method can be appropriately employed. For example, the measured value of the suction temperature sensor 16 may be corrected only according to the posture of the flap, that is, the wind direction, and it is blown out from the air outlet as well as the wind direction as in the air conditioner described in Patent Document 1. The measured value of the suction temperature sensor 16 may be corrected in consideration of the air volume.

Correction of the measured value of the suction temperature sensor 16 is performed when the posture of the flap 5a is the posture closest to the suction port 4 of the indoor unit 1. That is, it is performed when the upper surface or the lower surface of the strip-like flap 5a is most facing the suction port 4 side. In the present embodiment, the correction is performed when the lower surface 5a1 (see FIG. 2) of the flap 5a is facing the suction port 4 side most in the movable range of the flap 5a (so-called downward blowing).
When the position of the flap is closest to the air inlet of the indoor unit, in the case of a ceiling-mounted type (ceiling-buried type and ceiling-mounted type) as in the indoor unit 1 according to the present embodiment, when the bottom blowing that generates a downward airflow In the case of a wall-mounted indoor unit that has a suction port on the top surface, it is a top-blowing indoor unit that has an air outlet on the top surface and a suction port on the side surface or bottom surface, when the top blows to generate upward airflow In the case of horizontal blowing, a horizontal air flow is generated.

  In this embodiment, the type of suction temperature correction can be selected according to the operation mode of the indoor unit 1 including the attitude control of the flap 5a. Specifically, for example, the circulating airflow with the first suction temperature correction based on the posture of the flap 5a and frequent or periodic posture change of the flap 5a as in the case where the user selects the downward wind direction, for example, The second suction temperature correction when the operation mode such as the mode is adopted can be selected.

  In the circulating airflow mode, as described above, the cycle including the first to fourth steps is repeated a predetermined number of times until the room temperature reaches the target temperature. Although the time of each step is not particularly limited in the present invention, it can be, for example, about 1 to 10 minutes. Since this circulation airflow mode is intended to bring the indoor temperature close to the target temperature quickly and uniformly, it stops when there is no difference between the indoor temperature and the target temperature, and switches to the predetermined operation mode of the indoor unit 1. .

FIG. 3 is a diagram for explaining the state of the blown air when the circulating airflow operation mode is adopted in the indoor unit 1 according to the present embodiment. It is explanatory drawing which looked at the indoor unit 1 from upper direction, and each blower outlet 5 is described with the dotted line.
In the first step, as shown in FIG. 3 (a), the postures of the pair of opposing flaps are controlled so that a horizontal air current is blown out like the right flap 5a of FIG. The posture of the pair of flaps to be controlled is controlled so that air is not substantially blown out from the outlet 5 where the flap is disposed, thereby increasing the wind speed of the horizontal airflow. In the example shown in FIG. 3, horizontal airflow is blown from the left and right outlets 5, and the postures of the flaps of the upper and lower outlets 5 are controlled so that air is not substantially blown from the outlets 5. In FIG. 3, the horizontal airflow is indicated by a white arrow, and the downward airflow is indicated by a black arrow.

In the subsequent second step, as shown in FIG. 3B, all the flaps of the four outlets 5 are subjected to posture control so that the downward airflow is blown out like the flap 5a on the left side of FIG. And blow out the air.
In the subsequent third step, as shown in FIG. 3 (c), the horizontal airflow is blown out in the first step, and the flap postures of the left and right outlets in FIG. 3 are controlled so that air is not substantially blown out. At the same time, the posture of the remaining upper and lower flaps is controlled so that the horizontal air current is blown out, and the wind speed of the horizontal air current is increased.
In the subsequent fourth step, as shown in FIG. 3 (d), the posture is controlled so that the downward airflow is blown out of all the flaps of the four outlets 5, and the air is blown out.

  For example, when switching from the first step to the second step or when switching from the second step to the third step, the suction temperature correction is performed at the time of switching between the steps. In this embodiment, the posture of the flap 5a is a period. In the circulating airflow mode that switches automatically, the second suction based on the moving average value, which is the average value of the suction temperature after the first suction temperature correction, rather than the first suction temperature correction based on the posture of the flap 5a. Perform temperature correction.

  FIG. 4 is a diagram illustrating an example of the first correction temperature and the second correction temperature when the circulating airflow operation mode is employed. In FIG. 4, the thick solid line a indicates the first temperature correction, and the thin dotted line b indicates the second temperature correction. In the lower region of the figure, the solid line indicated by c represents the number of pulses corresponding to the posture of the flap 5a of the pair of opposed outlets 5 (the flap position represents the minimum, in the indoor unit 1 according to the present embodiment, That is, the “0” pulse indicates the fully closed position, and the flap opens as the pulse increases, and the dotted line indicated by d indicates a pulse corresponding to the posture of the flaps 5 a of the remaining pair of outlets 5. Shows the number. When the number of pulses is the minimum value (zero pulse), the flap 5a is in a closed state, and when the number of pulses is the maximum value, the flap 5a blows out downward airflow (downward blowing), and the number of pulses is maximum. When the value is approximately halfway between the minimum value and the minimum value, the flap 5a blows a horizontal air current (horizontal blowing). In other words, in FIG. 4, the periods indicated by I to IV indicate the first to fourth steps in the circulating airflow mode, respectively.

  In the first temperature correction, as indicated by symbol h in FIG. 4, a phenomenon called hunting occurs in which the corrected suction temperature rapidly rises or falls in a short time. In this embodiment, after the correction, The moving average value of the suction temperature is used as the corrected suction temperature, and as shown by the thin dotted line b in FIG. 4, the hunting is absorbed or relaxed to obtain a corrected temperature that changes gently. As a result, the rotation speed of the compressor controlled based on the corrected suction temperature value can be prevented from frequently switching, the life of the compressor is reduced, or the refrigerant temperature of the indoor unit is suddenly changed. This prevents the blowout temperature from changing. Note that the rotation speed of the compressor is controlled not only based on the corrected suction temperature but also based on other measured values such as the floor temperature of the air-conditioning room and the outside air temperature.

[Other variations]
The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.
For example, in the embodiment described above, the ceiling embedded type is exemplified as the indoor unit, but the present invention is not limited to this, and as long as the suction temperature correction is performed, for example, the ceiling type The present invention can also be applied to indoor units, wall-mounted indoor units, floor-standing indoor units, and the like.

  In the above-described embodiment, the circulation airflow mode is exemplified as a case where the flap posture is periodically changed. However, the present invention is not limited to this, and the flap posture is, for example, a horizontal blowing mode. The present invention can also be applied when performing a so-called swing operation mode in which the period from the start to the downward blowing is continuously changed.

  In the above-described embodiment, the second suction temperature correction is performed based on the moving average value of the first suction temperature correction. However, the present invention is not limited to this, and some past Other “average values” such as the average value of the suction temperature after the first suction temperature correction at the time (for example, one minute before) and the suction temperature after the first suction temperature correction at the present time are adopted. You can also.

Moreover, although embodiment mentioned above demonstrated taking the case of the heating operation as an example, this invention is not limited to this, This invention is applicable also at the time of air_conditionaing | cooling operation.
In the above-described embodiment, the temperature correction is performed when the flap posture is closest to the suction port. However, the temperature correction may be performed in a case other than this state.

1: Indoor unit 2: Casing 3: Cosmetic panel 4: Suction port 5: Air outlet 5a: Flap 6: Suction grill 7: Filter 8: Indoor fan 9: Heat exchanger 10: Motor 11: Impeller 12: Drain pan 13: Suction hole 14: Blowout hole 15: Bell mouth 16: Suction temperature sensor C; Ceiling P: Control unit

Claims (5)

An indoor unit (1) comprising a suction temperature sensor (16) and a control unit (P) for correcting the measured value of the suction temperature sensor (16) based on the posture of the flap (5a),
The control unit (P) performs a first suction temperature correction based on the posture of the flap (5a) and a second suction temperature correction based on an average value of the suction temperature after the first suction temperature correction. The indoor unit (1) selected according to the operation mode of the indoor unit (1) including posture control of the flap (5a).   The correction of the measured value of the suction temperature sensor (16) is performed when the posture of the flap (5a) is a flap posture closest to the suction port (4) of the indoor unit (1). Indoor unit (1).   The indoor unit (1) according to claim 1 or 2, wherein the second suction temperature correction is selected in an operation mode in which the posture of the flap (5a) is periodically switched.   The indoor unit (1) according to any one of claims 1 to 3, wherein the second suction temperature correction is a correction based on a moving average value of the suction temperature after the first suction temperature correction. . The indoor unit (1) according to any one of claims 1 to 4, wherein the indoor unit (1) is a ceiling-mounted or ceiling-buried type indoor unit (1) that blows out in four directions.

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