JP2007212135A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid a reduction in air conditioning performance when restarting a compressor stopped as a result of an abnormal operation such as an overload. <P>SOLUTION: An air conditioner that has a refrigerant circulation circuit configured to circulate a refrigerant discharged from the compressor from a condenser to an evaporator, an electric expansion valve which is disposed in a liquid pipe between the condenser and the evaporator and whose travel is controlled by an electrical signal, and a microcomputer for controlling the operation of the compressor and electric expansion valve, comprises a control means for, when the microcomputer restarts the compressor after stopping it as a result of an abnormal operation, such as an overload, causing any one of the temperature, pressure and direct current of the refrigerant circulation circuit to deviate from a predetermined range, controlling the travel of the electric expansion valve in an opening direction beyond that in the stop phase. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an air conditioner.

As a conventional air conditioner control device, for example, JP-A-59-183255 shown in FIG. 13 can be mentioned.
In the figure, 1 is a compressor, 2 is a condenser, 3 is an electric expansion valve, and 4 is an evaporator. Reference numeral 5 denotes an expansion valve control circuit for adjusting the valve opening degree of the electric expansion valve 3, and an inlet of the evaporator 4 detected by a temperature detector 5A provided at the inlet of the evaporator 4 and a temperature detector 5B provided at the outlet, An electric signal for controlling the opening of the electric expansion valve 3 is output so that the temperature difference at the outlet becomes a constant value. 6 is a control circuit for controlling the operation of the compressor 1 of the air conditioner, and controls the operation and stop of the compressor 1 by the difference between the setting device 6A for inputting the set temperature and the room temperature detector 6b for detecting the room temperature. Yes.

  Next, the operation will be described. FIG. 14 is an operation explanatory diagram of a compressor and an electric expansion valve of a conventional air conditioner. In the operation state of the air conditioner, the operation control of the compressor 1 is performed by comparing the temperature set by the setting device 6A by the compressor control circuit 6 with the temperature detected by the room temperature detector 6B. The opening degree of the expansion valve 3 is controlled so that the temperature difference between the inlet and outlet of the evaporator 4 detected by the temperature detectors 5A and 5B by the circuit 5 is constant. When the compressor stops at time T0, a signal is transmitted from the compressor control circuit 6 to the expansion valve control circuit 5 to control the valve opening of the electric expansion valve 3 to be fully open. As a result, the refrigerant easily flows, and the pressure balance between the high-pressure side and the low-pressure side is quickly performed in about several tens of seconds. When the compressor is restarted at time T1, a control signal is transmitted from the compressor control circuit 6 to the electric expansion valve 3 via the expansion valve control circuit 5, and the throttle valve is controlled to an appropriate throttle state so that the air conditioner is in a normal operating state. Will be.

FIG. 15 is a configuration diagram of a conventional electric expansion valve. In the figure, reference numeral 7 denotes a driving pulse motor which can be rotated at almost an arbitrary angle in either forward or reverse directions in accordance with an electric signal from the control circuit 5. Reference numeral 8 denotes a drive screw that converts the rotary motion of the output shaft of the drive pulse motor 7 into a reciprocating motion to move the valve 9 up and down. Reference numeral 10 denotes a valve seat, and the refrigerant flows between the valve 9 and the valve seat 10, and the pressure reduction amount can be adjusted by adjusting this interval by the vertical movement of the valve 9.
JP 59-183255 A JP 63-163748 A Japanese Unexamined Patent Publication No. 64-19256 JP-A-61-92375 JP-A-5-346279

  Since the conventional air conditioner is configured as described above, when the compressor 1 is stopped, the opening degree of the electric expansion valve 3 is used to balance the pressure on the high pressure side and the low pressure side where a pressure difference occurs. Since this is fully open, there was a problem that sound was generated when pressure was equalized.

  Moreover, since the opening degree of the electric expansion valve 3 is fully opened regardless of the capacity and capacity of the outdoor unit when the compressor 1 is stopped, the outdoor unit is secured so that a uniform pressure can be secured when the electric expansion valve 3 is fully opened. Therefore, it is necessary to mount the electric expansion valve 3 according to the capacity and capacity.

  Further, even when the compressor 1 is stopped due to any of the refrigerant cycle temperature, pressure, or current being out of a predetermined range as a result of abnormal operation such as overload, the electric expansion is performed regardless of the cause of the compressor 1 being stopped. Since the opening degree of the valve 3 is the same as the opening degree of the compressor stop due to the air conditioning temperature, there is a problem that it is impossible to avoid an overload state while the compressor is stopped.

  Further, as a result of abnormal operation such as overload, any of the refrigerant cycle temperature, pressure, and current becomes outside the predetermined range, and after the compressor 1 is stopped for a certain period of time, the outdoor unit is Regardless of the capacity and capacity, the opening degree of the electric expansion valve 3 is controlled, so that there is a problem that the air-conditioning capacity is lowered and the air expansion capacity does not cool or warm.

  Moreover, since the electric expansion valve control is performed so that the temperature difference between the inlet and outlet of the evaporator 4 is constant regardless of the form or capacity of the indoor unit, there is a problem as described above.

  Further, the electric expansion valve 3 repeats the opening operation and the closing operation, so that an error occurs between the electric expansion valve 3 and the set opening degree command position from the expansion valve control circuit unit 5 due to the error and variation of the electric expansion valve 3. In order to avoid this error, it is necessary to perform the reference position resetting process. However, since the reference position resetting process temporarily applies stress to the electric expansion valve 3, the electric expansion valve is frequently used. 3 is a factor of quality degradation.

  The present invention has been made to solve such a problem. When the compressor is stopped, the starting characteristic for restarting the compressor is ensured, and generation of sound at the time of pressure equalization by the electric expansion valve is achieved. It aims at suppressing.

  It is another object of the present invention to share parts of the electric expansion valve.

  It is another object of the present invention to avoid an overload condition when the compressor is stopped when the compressor is stopped due to an abnormal operation such as an overload.

  It is another object of the present invention to prevent the air conditioning capacity from being lowered when the compressor is stopped and restarted as a result of abnormal operation such as overload.

  Moreover, it aims at suppressing the fall of an air-conditioning capability by controlling an electric expansion valve according to the form or capacity | capacitance of an indoor unit.

  It is another object of the present invention to reduce the frequency of the process for resetting the reference position of the electric expansion valve and suppress the deterioration of the quality of the electric expansion valve.

  The air conditioner according to the present invention constitutes a refrigerant circulation circuit that circulates refrigerant discharged from the compressor from the condenser to the evaporator, and opens a valve by an electric signal in a liquid pipe between the condenser and the evaporator. In an air conditioner having a microcomputer that controls the operation of the compressor and the electric expansion valve by adjusting the degree of the electric expansion valve, as a result of abnormal operation such as overload, the temperature, pressure, DC current of the refrigerant circuit When one of the above is outside the specified range and the microcomputer stops the compressor, when the microcomputer restarts the compressor, the opening of the electric expansion valve is expanded from the opening at the stop to the opening direction. It is characterized by comprising control means for controlling.

  The air conditioner according to the present invention can avoid the problem that the air conditioning capability is reduced and the air conditioner does not cool or warm.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of an air conditioner according to Embodiment 1 of the present invention. In the figure, 1 is a compressor, and the compressor 1, the condenser 2, the electric expansion valve 3, and the evaporator 4 are sequentially connected in an annular manner through a refrigerant pipe to constitute a refrigeration cycle. 5 is a blower fan of the condenser 2, and 6 is a blower fan of the evaporator 4.

  The compressor 1 is controlled via a compressor control relay 10 based on a command from the outdoor unit control microcomputer 11.

  The electric expansion valve 3 is controlled via the expansion valve circuit control unit 12 based on a command from the outdoor unit control microcomputer 11.

  7a is a discharge refrigerant temperature detection thermistor that detects the temperature of the refrigerant discharged from the compressor 1, 7b is a condenser temperature detection thermistor that detects the temperature of the condenser 2, and 7c is a condenser outlet that detects the temperature of the outlet of the condenser 2. It is a temperature detection thermistor, and data from each thermistor is taken into the microcomputer 11 for outdoor unit control. Reference numeral 8a denotes a high pressure switch operated by pressure, and reference numeral 8b denotes a low pressure switch operated by pressure. The operating states of the high pressure switch 8a and the low pressure switch 8b are taken into the microcomputer 11. Reference numeral 9 denotes a thermo switch that operates according to temperature, and the operating state of the thermo switch 9 is taken into the microcomputer 11.

  15a is an indoor temperature detection thermistor that detects the temperature of the indoor temperature, 15b is an evaporator temperature detection thermistor that detects the temperature of the evaporator 4, and 15c is an evaporator inlet temperature detection thermistor that detects the temperature of the inlet of the evaporator 4. The data from each thermistor is taken into the indoor unit control microcomputer 14.

  Reference numeral 13 denotes a remote controller for selecting an operation command and a state such as cooling or heating. The contents of the set state of the remote controller 13 are taken into the indoor unit control microcomputer 14. The indoor unit control microcomputer 14 controls the blower fan 6 and transmits an operation command to the outdoor control microcomputer 11 based on the set state of the remote controller 13.

The operation of the air conditioner configured as described above will be described.
First, when the air conditioner is operated, the outdoor control microcomputer 11 compares the temperature set by the remote controller 13 with the temperature detected by the indoor temperature detection thermistor 15a to control the operation of the compressor 1. Is done.

  FIG. 2 is a diagram showing the sound during pressure equalization by the setting of the opening degree of the electric expansion valve when the compressor is stopped and the starting characteristics at the time of restart. As shown in the figure, the opening setting of the electric expansion valve that can minimize the sound during pressure equalization and ensure sufficient start characteristics at restart is the point where both curves intersect. The opening of the electric expansion valve is S1.

  Here, when the room temperature deviates from the temperature set by the remote controller 13 or when the operation is stopped by the remote controller 13, the compressor 1 is stopped. At this time, the opening degree of the electric expansion valve 3 attached to the outlet of the condenser 2 is set to S1 obtained in FIG.

FIG. 3 is an explanatory view of the operation of the compressor and the electric expansion valve. As shown in the figure, when the compressor 1 is stopped at time T0, a signal is transmitted from the outdoor control microcomputer 11 to the expansion valve circuit controller 12, and the opening degree of the electric expansion valve 3 is controlled to S1. When the compressor 1 is restarted at time T1, the electric expansion valve 3 is controlled to an appropriate throttle state.

  As a result, when the compressor 1 is stopped, the opening degree of the electric expansion valve 3 is set to a constant opening degree (S1) that is not fully opened, thereby ensuring the starting characteristics for restarting the compressor 1. And the sound at the time of equalization can be suppressed.

  An air conditioner according to an embodiment of the present invention constitutes a refrigerant circulation circuit that circulates refrigerant discharged from a compressor from a condenser to an evaporator, and electrically connects a liquid pipe between the condenser and the evaporator. In an air conditioner having a microcomputer that controls the operation of the compressor and the electric expansion valve by providing an electric expansion valve that adjusts the valve opening according to the signal, when the compressor stops, the compressor is restarted Control means is provided for setting the opening degree of the electric expansion valve to a predetermined opening degree that is not fully open so as to ensure the starting characteristics and suppress the sound during pressure equalization.

  The air conditioner according to the embodiment of the present invention ensures start characteristics for restarting the compressor by setting the opening of the electric expansion valve to a predetermined opening that is not fully opened when the compressor stops. In addition, it is possible to suppress the possibility of sound being generated during pressure equalization.

Embodiment 2. FIG.
Embodiment 2 of the present invention will be described below with reference to the drawings. 4 and 5 are diagrams showing the second embodiment. FIG. 4 is a diagram for explaining the operation of the compressor and the electric expansion valve. FIG. 5 is a diagram illustrating when the pressure is equalized by setting the opening of the electric expansion valve when the compressor is stopped. It is a figure showing the starting characteristic at the time of a sound and a restart.

  In FIG. 5, 25a is a pressure equalizing sound of an outdoor unit of 3 hp, 25b is a pressure equalizing sound of an outdoor unit of 4 hp, and 25c is a pressure equalizing sound of an outdoor unit of 5 hp. The opening degree setting of the electric expansion valve 3 that can suppress the sound during pressure equalization to a minimum and sufficiently ensure the starting characteristics at the time of restart is a point where the respective curves intersect. The opening of the valve 3 is S1 for an outdoor unit of 3 horsepower, S2 for an outdoor unit of 4 horsepower, and S3 for an outdoor unit of 5 horsepower.

  Here, when the room temperature deviates from the temperature set by the remote controller 13 or when the operation is stopped by the remote controller 13, the compressor 1 is stopped. At this time, as shown in FIG. 4, the opening degree of the electric expansion valve 3 attached to the outlet of the condenser 2 is set to S1, S2, or S3 obtained in FIG. 5 according to the capacity of the outdoor unit. Set.

  As a result of the above, it is possible to make the parts of the electric expansion valve 3 common by changing the constant opening of the electric expansion valve 3 when the compressor 1 is stopped according to the capacity and capacity of the outdoor unit. Become.

  In the air conditioner according to the embodiment of the present invention, the predetermined opening degree of the electric expansion valve when the compressor is stopped is set to the opening degree according to the capacity and capacity of the outdoor unit.

  In the air conditioner according to the embodiment of the present invention, the opening of the electric expansion valve when the compressor is stopped is set to an opening according to the capacity and capacity of the outdoor unit, so that the components of the electric expansion valve Can be made common.

Embodiment 3 FIG.
Embodiment 3 of the present invention will be described below with reference to the drawings. 6 and 7 are diagrams showing the third embodiment, FIG. 6 is a control flowchart of the electric control valve, and FIG. 7 is an operation explanatory diagram of the compressor and the electric expansion valve.

  In FIG. 6, first, in step 101, data of the discharge refrigerant temperature detection thermistor 7a, the condenser temperature detection thermistor 7b, and the condenser outlet temperature detection thermistor 7c that detect the temperature of the refrigeration cycle are captured. Next, in step 102, the operating states of the high pressure switch 8a and the low pressure switch 8b for detecting the pressure state of each part of the refrigeration cycle are captured. Next, in step 103, the operating state of the thermo switch 9 is captured.

  Next, in step 104, it is determined whether or not the compressor 1 is in operation. If the compressor 1 is not in operation, the process returns to step 101, and the temperature of each part of the refrigeration cycle is captured.

  If the compressor 1 is in operation at step 104, it is determined at step 105 whether any of the data fetched at steps 101, 102, 103 is within a predetermined range.

  In step 105, if any of the data fetched in steps 101, 102, 103 is within a predetermined range, the process returns to step 101, and the temperature of each part of the refrigeration cycle is fetched.

  In step 105, if the data fetched in steps 101, 102, 103 is outside the predetermined range, in step 106, after resetting the 3-minute timer t for stopping the compressor 1 for 3 minutes, A timer t for stopping the compressor 1 for 3 minutes is set at 107, and the compressor 1 is stopped at step 108.

  Next, at step 109, as shown in FIG. 7, the opening degree of the electric expansion valve 3 is set in the opening direction.

  Next, at step 110, the compressor 1 stop 3-minute timer t set at step 107 is decremented.

  Next, in step 111, it is determined whether or not the 3-minute timer t for stopping the compressor 1 has become zero. If the 3-minute timer t for stopping the compressor 1 is not 0 in step 111, the process returns to step 108 and the compressor 1 is stopped. If the 3-minute timer t for stopping the compressor 1 is 0 in step 111, the operation of the compressor 1 is restarted in step 112, and the process returns to step 101.

  As a result, in the case of abnormal operation such as overload, when the outdoor unit control microcomputer 11 stops the compressor 1, the opening degree of the electric expansion valve 3 can be controlled to be widened in the opening direction. As a result, it is possible to avoid an overload condition when the compressor is stopped.

Embodiment 4 FIG.
Embodiment 4 of the present invention will be described below with reference to the drawings. 8 and 9 are diagrams showing the fourth embodiment, FIG. 8 is a control flowchart of the electric control valve, and FIG. 9 is an operation explanatory diagram of the compressor and the electric control valve.

In FIG. 8, steps 101 to 111 are the same as those in the third embodiment.
If the 3-minute timer t for stopping the compressor 1 is 0 in step 111, the capacity and capacity of the outdoor unit are recognized in step 113, and the capacity and capacity of the outdoor unit recognized in step 113 are determined in step 114. The opening degree of the electric expansion valve corresponding to the opening direction is output to the electric expansion valve 3, and the compressor 1 is restarted in step 112.

  As a result of the above, when the outdoor unit controlling microcomputer 11 restarts the compressor 1 after the outdoor unit controlling microcomputer 11 stops the compressor 1 in the case of abnormal operation such as overload, it is shown in FIG. Thus, since it can control so that the opening degree of the electric expansion valve 3 may be expanded in the opening direction by the capacity and capacity of the outdoor unit, it is possible to suppress a decrease in air conditioning capacity.

  In the air conditioner according to the embodiment of the present invention, as a result of abnormal operation such as overload, any one of the temperature, pressure, and direct current in the refrigerant circuit becomes outside the predetermined range, and the microcomputer stops the compressor. When the microcomputer restarts the compressor, the microcomputer is provided with control means for controlling the opening degree of the electric expansion valve in the opening direction in accordance with the capacity and capacity of the outdoor unit.

  In the air conditioner according to the embodiment of the present invention, as a result of abnormal operation such as overload, any one of the temperature, pressure, and direct current in the refrigerant circuit becomes outside the predetermined range, and the microcomputer stops the compressor. When the microcomputer restarts the compressor, the air-conditioning capacity is reduced and the cooling does not cool by controlling the opening of the electric expansion valve to open in the open direction according to the capacity and capacity of the outdoor unit. Or the problem of not warming can be avoided.

Embodiment 5 FIG.
Embodiment 5 of the present invention will be described below with reference to the drawings. FIG. 10 is a diagram showing the fifth embodiment, and is a control flowchart of the electric expansion valve.

  The electric expansion valve 3 detects the subcooling temperature detected by the outdoor condenser temperature detection thermistor 7b and the outdoor condenser outlet temperature detection thermistor 7c in the cooling operation, and the indoor evaporator temperature in the heating operation. The subcooling temperature detected by the thermistor 15b and the indoor evaporator outlet thermistor 15c is controlled to be constant.

  In the figure, first, in step 201, the indoor unit generates correction data indicating the target subcooling temperature based on the form or capacity.

  Next, in step 202, the outdoor unit receives the correction data generated by the indoor unit in step 201 from the indoor unit by communication.

  Next, the outdoor unit converts the correction data obtained in step 202 into control data in step 203.

  Next, in step 204, the outdoor unit starts control of the electric expansion valve 3 based on the control data converted in step 203.

  As a result, since the outdoor unit can perform the opening degree control of the electric expansion valve according to the form or capacity of the indoor unit, it is possible to suppress a decrease in air conditioning capability.

  The air conditioner according to the embodiment of the present invention includes a control means for the outdoor unit to recognize the form or capacity of the indoor unit and to control the opening degree of the electric expansion valve according to the recognized result. is there.

  The air conditioner according to the embodiment of the present invention includes a control means for the outdoor unit to recognize the form or capacity of the indoor unit and to control the opening degree of the electric expansion valve according to the recognized result. The problem that the air-conditioning capacity is reduced and the air does not cool or warm can be avoided.

Embodiment 6 FIG.
Embodiment 6 of the present invention will be described below with reference to the drawings.
11 and 12 show the sixth embodiment, FIG. 11 is a control flowchart of the electric expansion valve, and FIG. 12 is an operation explanatory view of the electric expansion valve.
In FIG. 11, first, in step 301, it is detected whether the operation mode setting content of the remote controller 13 has changed to the stop mode or the air blowing mode.

  When the operation mode setting content of the remote controller 13 is changed to the stop mode or the air blowing mode at step 301, the change counter n is incremented at step 302.

  Next, in step 303, it is determined whether or not the change count counter n has reached 10 or more. If the change number counter n is less than 10 in step 303, the process returns to step 301.

  If the change number counter n is 10 times or more at step 303, the process of setting the reference position of the opening degree of the electric expansion valve 3 shown in FIG.

  In step 304, after the setting process of the reference position of the opening degree of the electric expansion valve 3 is completed, the change counter n = 0 is set in step 305, and the process returns to step 301.

  As a result, the quality of the electric expansion valve 3 can be prevented from being lowered without frequently performing the process of resetting the reference position of the electric expansion valve 3.

It is a whole block diagram of the air conditioner of this invention. It is a figure which shows Embodiment 1, and is a figure showing the sound at the time of equalization by the opening degree setting of the electric expansion valve when a compressor stops, and the starting characteristic at the time of restart. It is a figure which shows Embodiment 1 and is operation | movement explanatory drawing of the compressor and electric expansion valve of an air conditioner. It is a figure which shows Embodiment 2, and is operation | movement explanatory drawing of the compressor and electric expansion valve of an air conditioner. It is a figure which shows Embodiment 2, and is the figure showing the sound at the time of pressure equalization by the opening degree setting of the electric expansion valve when the compressor by the capacity | capacitance of an outdoor unit stops, and the starting characteristic at the time of restart. It is a figure which shows Embodiment 3, and is a control flowchart figure of an electric expansion valve. It is a figure which shows Embodiment 3, and is operation | movement explanatory drawing of the compressor and electric expansion valve of an air conditioner. It is a figure which shows Embodiment 4, and is a control flowchart figure of an electric expansion valve. It is a figure which shows Embodiment 4, and is operation | movement explanatory drawing of the compressor and electric expansion valve of an air conditioner. It is a figure which shows Embodiment 5, and is a control flowchart figure of an electric expansion valve. It is a figure which shows Embodiment 6, and is a control flowchart figure of an electric expansion valve. It is a figure which shows Embodiment 6, and is operation | movement explanatory drawing of an electric expansion valve. It is a refrigeration cycle figure of the conventional air conditioner. It is a block diagram of the electric expansion valve used for the conventional air conditioner. It is operation | movement explanatory drawing of the compressor and electric expansion valve of the conventional air conditioner.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Compressor, 2 Condenser, 3 Electric expansion valve, 4 Evaporator, 5 Blower fan, 6 Blower fan, 7a Discharge refrigerant temperature detection thermistor, 7b Condenser temperature detection thermistor, 7c Thermistor which detects condenser outlet temperature, 8a High pressure Pressure switch, 8b Low pressure switch, 9 Thermo switch, 10 Compressor control relay, 11 Outdoor unit control microcomputer, 12 Expansion valve circuit control unit, 13 Remote control, 14 Indoor unit control microcomputer, 15a Indoor temperature detection thermistor, 15b Evaporation Temperature detector thermistor, 15c Evaporator outlet temperature detection thermistor.

Claims (2)

  An electric expansion valve that forms a refrigerant circulation circuit that circulates refrigerant discharged from the compressor from the condenser to the evaporator, and adjusts the valve opening degree by an electric signal in a liquid pipe between the condenser and the evaporator In the air conditioner having a microcomputer that controls the operation of the compressor and the electric expansion valve, as a result of abnormal operation such as overload, any one of the temperature, pressure, or direct current of the refrigerant circulation circuit is When the microcomputer restarts the compressor after the microcomputer stops the compressor outside the predetermined range, the opening of the electric expansion valve is expanded in the opening direction from the opening at the time of stop. An air conditioner comprising control means for controlling as described above.   2. The air conditioner according to claim 1, further comprising a control unit configured to control the opening degree of the electric expansion valve so that the opening degree of the electric expansion valve is expanded in an opening direction from an opening degree when the outdoor expansion unit is open according to the capacity and capacity of the outdoor unit. Machine.

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