JP2012237482A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner that can evade a significant decrease of a heating capacity while suppressing frost formation.SOLUTION: The air conditioner in which an indoor unit and an outdoor unit are connected includes an outdoor heat exchanger temperature sensor that detects a temperature of an outdoor heat exchanger. At a heating operation, components which effect the pressure fluctuation of a refrigeration cycle are controlled so that the temperature of the outdoor heat exchanger is within a predetermined range. Accordingly, a defrosting operation is suppressed to the utmost extent, and the deterioration of amenities of a room can be avoided as much as possible.

Description

  The present invention relates to an air conditioner that can vary the operating frequency of a compressor.

  Conventionally, in the heating operation of an air conditioner in which the operating frequency of the compressor is variable, particularly when the outdoor temperature is low, the operating frequency of the compressor is maximized to ensure high heating capacity. However, when the outdoor temperature is low and the temperature of the outdoor heat exchanger drops below the freezing point due to the low outdoor temperature, frost adheres to and grows on the outdoor heat exchanger, and the efficiency of taking heat from the outdoor air decreases. , Heating capacity is greatly reduced.

  Therefore, when a certain condition is satisfied, a method of defrosting the outdoor heat exchanger by temporarily interrupting the heating operation and switching the refrigeration cycle in reverse is widely used (for example, see Patent Document 1).

JP-A-8-338673

  However, in the conventional air conditioner, during the defrosting operation, the heating is a reverse cycle operation, and it is necessary to interrupt the heating operation. Furthermore, once frosting starts even before the frost operation starts, The air flow is hindered by this, the heat exchange efficiency of the outdoor heat exchanger is reduced at an accelerated rate, and the heating capacity is greatly reduced.

  This invention solves the said conventional subject, and it aims at providing the air conditioner which can suppress frost formation and can avoid the significant fall of heating capability.

  In order to solve the conventional problems, the present invention is an air conditioner configured by connecting an indoor unit and an outdoor unit, and includes an outdoor heat exchanger temperature detection unit that detects the temperature of the outdoor heat exchanger. In the heating operation, by controlling the components that affect the pressure fluctuation of the refrigeration cycle so that the temperature of the outdoor heat exchanger is within a predetermined range, the defrosting operation can be suppressed as much as possible. It is possible to avoid the loss of indoor comfort as much as possible.

  The present invention can provide an air conditioner that can suppress frost formation and avoid a significant decrease in heating capacity.

1 is a block diagram of an air conditioner according to Embodiment 1 of the present invention. Conceptual diagram in the first embodiment The block diagram of the air conditioner in Embodiment 2 of this invention The block diagram of the air conditioner in Embodiment 3 of this invention

An air conditioner according to a first aspect of the present invention is an air conditioner configured by connecting an indoor unit and an outdoor unit, and includes an outdoor heat exchanger temperature detector that detects the temperature of the outdoor heat exchanger. During operation, by controlling the components that affect the pressure fluctuation of the refrigeration cycle so that the temperature of the outdoor heat exchanger is within a predetermined range, it is possible to suppress entry into the defrosting operation as much as possible. It can avoid impairing comfort as much as possible.

  An air conditioner according to a second aspect of the present invention is the air conditioner according to the first aspect of the present invention, which includes an indoor fan that blows air into the room, and that the indoor heat exchanger has a temperature within a predetermined range during heating operation. By lowering the fan speed, lowering the high-pressure side raises the low-pressure side and prevents frosting as much as possible.

  An air conditioner according to a third aspect of the invention includes the indoor fan for blowing air into the room, and the up / down air direction changing blades for changing the air direction up and down in the first or second invention, and the outdoor heat exchange during heating operation. Frosting as much as possible by lowering the high-pressure side and raising the low-pressure side by driving the upper and lower airflow direction changing blades in a direction that reduces the air flow rate into the room so that the temperature of the chamber is within a predetermined range Prevent entry into state.

  An air conditioner according to a fourth aspect of the present invention is the air conditioner according to the first to third aspects of the invention, comprising an indoor blower for blowing air into the room and a left / right wind direction changing blade for changing the wind direction to the left and right. By driving the left and right wind direction change blades in a direction to reduce the air flow rate into the room so that the temperature of the vessel is within a predetermined range, the low pressure side is raised by lowering the high pressure side, and frost formation is performed as much as possible Prevent entry into state.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a block diagram of an air conditioner according to a first embodiment of the present invention.

  In FIG. 1, a microcomputer 1, a compressor 2 having a variable operating frequency, and an outdoor heat exchanger temperature detection unit 3 that detects an outdoor heat exchanger temperature and sends the value to the microcomputer 1 are provided. The data table 4 in which the upper limit temperature and the lower limit temperature of the outdoor heat exchanger outside air temperature are set, and the outdoor heat exchanger temperature from the outdoor heat exchanger temperature detection unit 3 are compared by the data comparison unit 6, The calculation unit 7 predicts the frosting state.

  And by reducing the rotation speed of the indoor air blower 8, the low pressure is raised and the temperature of the outdoor heat exchanger is raised so as not to be in a frosting state as much as possible.

  The data table is created based on the comparison of the frost formation on the outdoor heat exchanger at any outdoor heat exchanger temperature, and the measured outdoor heat exchange for the frost formation on the outdoor heat exchanger. It can be inferred from the vessel temperature.

  As described above, in the present embodiment, the measured outdoor heat exchanger temperature is compared with the data table, and the outdoor heat exchanger is compared with the upper limit value of the outdoor heat exchanger temperature set in advance in the data table. By reducing the rotation speed of the indoor unit before starting to form frost, the low pressure can be increased with increasing the high pressure, and frost formation on the outdoor heat exchanger can be suppressed. As a result, the heat exchange efficiency of the outdoor heat exchanger is ensured, and the comfort of the indoor living environment is ensured.

FIG. 2 is an operation conceptual diagram of the indoor blower in the present embodiment. In FIG. 2, when the lower limit temperature T1 of the outdoor heat exchanger set in advance in the data table 4 is reached, the rotation speed of the indoor unit is set to a value (constant −n1) from the current rotation speed N, and the upper limit T2 is reached. For example, the number of rotations of the indoor unit is set to a value that is (constant + n2) from the current number of rotations N. This calculation is repeated, and when the rotation speed of the indoor unit reaches the lower limit value n3, this is set as the lower limit.

  As a result, it is possible to accurately predict the frost formation state on the outdoor heat exchanger while preventing a large decrease in capacity due to excessive reduction in the rotation speed of the indoor unit, and suppress frost formation on the outdoor heat exchanger. be able to. As a result, the heat exchange efficiency of the outdoor heat exchanger is ensured, and the comfort of the indoor living environment is ensured.

  Furthermore, the air conditioner of the present invention is configured such that the control for changing the rotation speed of the indoor unit can be interrupted by the operation of the main body operation switch 10 provided in the main body. This makes it possible to perform the same compressor frequency control as before without relying on the above control as necessary.

  The microcomputer 1 described above may be provided in either the indoor unit or the outdoor unit, and does not limit the installation position. The main body operation switch 10 may be provided in a remote controller or the like.

(Embodiment 2)
FIG. 3 is a block diagram of an air conditioner according to the second embodiment of the present invention. The difference from the first embodiment is that the vertical wind direction changing blade 11 is driven.

  And the up-and-down air direction change blade | wing 11 is driven and ventilation resistance is increased, the low pressure | voltage is raised and the temperature of an outdoor heat exchanger is raised, and it is trying not to be in a frosting state as much as possible.

(Embodiment 3)
FIG. 4 is a block diagram of an air conditioner according to the third embodiment of the present invention. The difference from the first and second embodiments is that the left and right wind direction changing blades 12 are driven.

  And by driving the right and left wind direction changing blades 12 and increasing the ventilation resistance, the low pressure is raised and the temperature of the outdoor heat exchanger is raised, so that the frosting state is prevented as much as possible. In addition, it is good also as control which drives the up-and-down wind direction change blade | wing 11 together.

  As described above, the air conditioner according to the present invention avoids a state in which ventilation is hindered by frost, the heat exchange efficiency of the outdoor heat exchanger is accelerated, and the heating capacity is greatly reduced. By suppressing frost formation on the outdoor heat exchanger during heating operation, the heating capacity is not significantly reduced, and the frequency of defrosting operation is also reduced, improving the comfort of the indoor living environment. Is.

DESCRIPTION OF SYMBOLS 1 Microcomputer 2 Compressor 3 Outdoor heat exchanger temperature detection part 8 Indoor fan 11 Vertical wind direction change blade 12 Left and right wind direction change blade

Claims (4)

An air conditioner configured by connecting an indoor unit and an outdoor unit, comprising an outdoor heat exchanger temperature detection unit that detects the temperature of the outdoor heat exchanger, and during the heating operation, An air conditioner that controls components that affect pressure fluctuations in a refrigeration cycle so that the temperature falls within a predetermined range. The indoor fan which ventilates indoors is provided, The rotation speed of the said indoor fan is lowered | hung so that the temperature of the said outdoor heat exchanger may become in a predetermined range at the time of heating operation. Air conditioner. Equipped with an indoor blower that blows into the room and an up / down air direction change blade that changes the wind direction up and down, and reduces the amount of air blown into the room so that the temperature of the outdoor heat exchanger is within a predetermined range during heating operation The air conditioner according to claim 1 or 2, wherein the up-and-down wind direction changing blade is driven in a direction to be moved. An indoor blower that blows into the room and a left / right wind direction change blade that changes the wind direction to the left and right are provided, and the amount of air blown into the room is reduced so that the temperature of the outdoor heat exchanger is within a predetermined range during heating operation. The air conditioner according to any one of claims 1 to 3, wherein the left and right wind direction changing blades are driven in a direction to be moved.

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