JP2010261609A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner for finding release of a refrigerant to protect a compressor even while the refrigerant releases to some extent or more. <P>SOLUTION: This air conditioner includes a refrigerating cycle constituted by successively annularly connecting the compressor 8, a four-way valve 9, an outdoor heat exchanger 10, a flow rate-variable electric expansion valve 15 and an indoor heat exchanger 3, an outdoor fan 12 disposed near the outdoor heat exchanger 10, an indoor fan 4 disposed near the indoor heat exchanger 3, a discharge temperature sensor 14 detecting a discharge temperature of the refrigerating cycle, and an outdoor control device 13 memorizing a throttle opening of the electric expansion valve 15 and a discharge temperature. When the throttle opening of the electric expansion valve 15 is a set value or more, and the discharge temperature reaches a discharge temperature set value or more, the compressor 8 is stopped, thus the abnormality is surely determined while the refrigerant releases from a body to some extent, and a compressing mechanism section (not shown in drawing) in the compressor 8 and an oil of a motor (not shown in drawing) are protected from excessive temperature rise. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an air conditioner, and more particularly to protection control of a compressor in a refrigeration cycle.

  In conventional air conditioners, refrigeration cycle when refrigerant is small or refrigerant refrigeration cycle or some part of refrigeration cycle is clogged, especially for compressor protection control, is to protect the compressor from overheating. In general, a compressor temperature sensor and a discharge temperature sensor are attached, or an inner thermal protector is built in the compressor.

  However, the installation of such a sensor and the built-in protector have the problem that the manufacturing cost increases. Conventionally, the temperature of the indoor piping that detects the condensation temperature of the refrigerant in the refrigeration cycle is conventionally used in a heat pump type air conditioner. And a control device that controls the refrigeration cycle and includes an outdoor total operating current detection unit, an outdoor total operating current setting storage unit, an indoor piping temperature setting storage unit, and a determination unit. It is configured to stop the compressor when the indoor pipe temperature exceeds the set temperature for a predetermined time during cooling operation and when the indoor pipe temperature falls below the set temperature for heating operation during cooling operation. (For example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 2003-329312

  However, in the air conditioner having the above-described conventional refrigeration cycle protection control, there is a problem that malfunctions and misjudgments cannot be avoided depending on the air conditioning conditions and operating conditions installed in a state where the refrigerant has been removed to some extent. .

  The present invention solves the above-described conventional problems, and an object of the present invention is to provide an air conditioner that can appropriately perform abnormality determination of a refrigeration cycle from a state in which refrigerant has been removed to some extent.

  In order to solve the above-described conventional problems, the air conditioner of the present invention is formed by annularly connecting a compressor, a four-way valve, an outdoor heat exchanger, a variable flow rate expansion valve, and an indoor heat exchanger in order. A refrigeration cycle; an outdoor fan disposed in the vicinity of the outdoor heat exchanger; an indoor fan disposed in the vicinity of the indoor heat exchanger; a discharge temperature detecting means for detecting a discharge temperature of the refrigeration cycle; Storage means for storing a throttle opening of the expansion valve and a discharge temperature, and when the throttle opening of the expansion valve is equal to or higher than a set value and the discharge temperature is equal to or higher than the discharge temperature set value, the compressor is In this case, the abnormality can be reliably determined from the state in which the refrigerant has escaped from the main body to some extent, and the compression mechanism section in the compressor and the coil of the motor that drives the compression mechanism section can be protected from overheating.

The air conditioner of the present invention includes a compressor, a four-way valve, an outdoor heat exchanger, a variable flow rate expansion valve, an refrigeration cycle formed by sequentially connecting an indoor heat exchanger, and the outdoor heat exchange. An outdoor fan disposed in the vicinity of the cooler, an indoor fan disposed in the vicinity of the indoor heat exchanger, a discharge temperature detecting means for detecting a discharge temperature of the refrigeration cycle, a throttle opening degree and a discharge of the expansion valve Storage means for storing the temperature and the operating frequency of the compressor, the throttle opening of the expansion valve is equal to or greater than a set value, the discharge temperature is equal to or greater than the set value of the discharge temperature, and the operating frequency of the compressor is set to set operation. When the frequency exceeds the frequency, the compressor is stopped. The abnormality of the refrigerant can be reliably determined from the state in which the refrigerant has been removed from the main body to some extent, and the coil of the motor that drives the compression mechanism and the compression mechanism in the compressor. To protect against overheating Can.

  The air conditioner of the present invention is not affected by the installed environment and conditions, and can accurately determine abnormality even when the refrigerant gas is considerably exhausted and the remaining amount is small, and can reliably protect the compressor.

The circuit diagram of the refrigerant circuit of the air conditioner in Embodiment 1 of this invention Flow chart for explaining a control example of the air conditioner The flowchart explaining the other control example of the air conditioner The flowchart explaining the other control example of the air conditioner The flowchart explaining the other control example of the air conditioner

  A first invention includes a refrigeration cycle formed by sequentially connecting a compressor, a four-way valve, an outdoor heat exchanger, a variable flow rate expansion valve, and an indoor heat exchanger, and in the vicinity of the outdoor heat exchanger. An outdoor fan arranged, an indoor fan arranged in the vicinity of the indoor heat exchanger, a discharge temperature detecting means for detecting a discharge temperature of the refrigeration cycle, a throttle opening degree and a discharge temperature of the expansion valve are stored. Storage means for stopping the compressor when the throttle opening of the expansion valve is equal to or higher than a set value and the discharge temperature is equal to or higher than the discharge temperature set value. Thus, it is possible to reliably determine the abnormality from the state, and to protect the compression mechanism section in the compressor and the coil of the motor that drives the compression mechanism section from excessive temperature rise.

  A second invention includes a refrigeration cycle formed by sequentially connecting a compressor, a four-way valve, an outdoor heat exchanger, a variable flow rate expansion valve, and an indoor heat exchanger in an annular manner, and in the vicinity of the outdoor heat exchanger. An outdoor fan arranged, an indoor fan arranged in the vicinity of the indoor heat exchanger, a discharge temperature detecting means for detecting a discharge temperature of the refrigeration cycle, a throttle opening degree, a discharge temperature and the compression of the expansion valve Storage means for storing the operating frequency of the compressor, the throttle opening of the expansion valve is equal to or higher than a set value, the discharge temperature is equal to or higher than the discharge temperature set value, and the operating frequency of the compressor is equal to or higher than the set operating frequency. In this case, the compressor is stopped, so that abnormality can be reliably determined from the state in which the refrigerant has been removed from the main body to some extent, and the temperature of the compression mechanism section in the compressor and the motor coil that drives the compression mechanism section is excessively increased. Can be protected from.

  The third aspect of the invention is to stop the compressor particularly when the throttle opening degree of the expansion valve of the first aspect of the invention is equal to or higher than a set value and the discharge temperature is equal to or higher than the discharge temperature set value for a predetermined time. Thus, since the compressor does not stop in a transient state, the reliability of the compressor is improved.

  In particular, according to the fourth invention, the throttle opening degree of the expansion valve of the second invention is equal to or higher than a set value, the discharge temperature is equal to or higher than the discharge temperature set value, and the operating frequency of the compressor is equal to or higher than the set operating frequency for a predetermined time. In this case, the compressor is stopped, and the compressor does not stop in a transient state, so that the reliability of the compressor is improved.

  In the fifth aspect of the invention, when the compressor of the fourth aspect of the invention is stopped, the refrigerant shortage abnormality code is transmitted to the indoor unit of the air conditioner, and the indoor side user is notified of the refrigerant shortage. be able to.

  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)
The air conditioner in Embodiment 1 of this invention is demonstrated using FIG.1 and FIG.2.

FIG. 1 shows a circuit diagram of a refrigerant circuit of an air conditioner in the present embodiment. In FIG. 1, the air conditioner in this Embodiment forms the refrigerant circuit of the outdoor unit 2 with the compressor 8, the four-way valve 9, the outdoor heat exchanger 10, and the variable flow-type electric expansion valve 15, A refrigerant circuit is constituted by a connecting pipe 20 connecting the indoor heat exchanger 3 of the indoor unit 1.

The air conditioner also includes an indoor fan 4 disposed in the vicinity of the indoor heat exchanger 3, a fan motor 5 that drives the indoor fan 4, a temperature sensor 6 that detects room temperature, and detects and controls these. An indoor control device 7 to be performed, an outdoor fan 12, an outdoor air temperature sensor 11 for detecting outdoor air temperature, a discharge temperature sensor 14 as discharge temperature detecting means for detecting discharge temperature, a compressor 8, an electric expansion valve 15, and four-way An outdoor control device 13 for controlling the valve 9 is provided. The air conditioner is controlled by the indoor control device 7 and the outdoor control device 13.

  Next, the operation of the air conditioner in the present embodiment will be described according to the flowchart of FIG.

  First, when the processing of the air conditioner is started, it is determined whether the compressor 8 is operating. If the compressor 8 is operating, the current opening degree EXP of the electric expansion valve 15 is stored in the outdoor control device 13. To do. In other words, in the present embodiment, the outdoor control device 13 also serves as storage means for storing various data such as the opening degree EXP.

  When the current opening EXP is smaller than the set value exp1, normal operation is performed. When the current opening EXP is larger than the set value exp1, the discharge temperature Td detected by the discharge temperature sensor 14 is stored in the outdoor control device 13. Next, when the current discharge temperature Td is lower than the discharge temperature set value t1, the operation returns to the normal operation, and when it becomes higher than the discharge temperature set value t1, the compressor 8 is stopped.

  As described above, in the present embodiment, even if the refrigerant is normally removed to some extent, the electric expansion valve 15 is opened to lower the discharge temperature, and the refrigeration cycle of the compressor 8 and the like does not become abnormal. When the indoor / outdoor load is high, the opening degree of the electric expansion valve 15 exceeds the set opening degree, the temperature control of the refrigeration cycle by the electric expansion valve 15 becomes impossible, and the discharge temperature rises. A motor that drives the compression mechanism part and the compression mechanism part in the compressor 8 that is configured to judge the abnormality and stop the compressor 8 so that the abnormality can be reliably judged from a state in which the refrigerant has escaped from the main body to some extent. This coil can be protected from overheating.

  Next, another control example of the air conditioner according to the present embodiment will be described with reference to the flowchart of FIG.

  When the processing of the air conditioner starts, it is determined whether the compressor 8 is operating. When the compressor 8 is operating, the current opening degree EXP of the electric expansion valve 15 is stored in the outdoor control device 13. When the current opening degree EXP of the electric expansion valve 15 is smaller than the set value exp2, normal operation is performed, and when the current value EXP is larger than the set value exp2, the current frequency CompHz of the compressor 8 is stored in the outdoor control device 13. To do.

When the current frequency CompHz of the compressor 8 is lower than the set operation frequency Hz2, the normal operation is performed, and when the frequency CompHz is higher than the set operation frequency Hz2, the discharge temperature Td detected by the discharge temperature sensor 14 is measured outdoors. Store in the control device 13. Next, when the current discharge temperature Td is smaller than the discharge temperature set value t2, the compressor 8 is stopped when returning to normal operation and greater than the discharge temperature set value t2.

As described above, in this control example, even if the refrigerant is normally removed to some extent, the electric expansion valve 15 is opened to lower the discharge temperature, and the refrigeration cycle of the compressor 8 and the like does not become abnormal. When the indoor or outdoor load is high, etc., it is configured to determine the abnormality based on the expansion valve opening degree and discharge temperature, and to prevent false detection by determining the compressor frequency above the set operating frequency. Abnormality can be reliably determined from the state in which the refrigerant has escaped from the main body to some extent, and the motor coil and compressor parts of the compressor 8 can be protected from excessive temperature rise.

  Next, another control example of the air conditioner in the present embodiment will be described with reference to the flowchart of FIG.

  First, when the processing of the air conditioner is started, it is determined whether the compressor 8 is operating. If the compressor 8 is operating, the timer count is set at time T1, and the current opening of the electric expansion valve 15 is set. EXP is stored in the outdoor control device 13. When the current opening degree EXP of the electric expansion valve 15 is smaller than the set value exp3, a normal operation is performed, and when the current opening EXP is larger than the set value exp3, the discharge temperature Td detected by the discharge temperature sensor 14 is used as the outdoor control device. 13 is stored.

  Next, when the current discharge temperature Td is smaller than the discharge temperature set value t3, the current state is maintained, and when the current discharge temperature Td is larger than the discharge temperature set value t3, the opening degree EXP and the discharge temperature until the time T1 becomes equal to or greater than the predetermined time Ts3. When the state where Td is larger than the respective set values is continued, the compressor 8 is stopped. When the opening degree EXP and the discharge temperature Td cannot be maintained higher than the set values, the operation is continued until the predetermined time Ts3 or more.

  As described above, in this control example, even when the refrigerant is normally removed to some extent, the electric expansion valve 15 is opened to lower the discharge temperature, and the refrigeration cycle such as the compressor 8 does not become abnormal. When the outdoor load is high, the abnormality is determined based on the opening degree of the expansion valve and the discharge temperature, and the compressor 8 is not stopped in a transient state by continuing for a certain period of time. Therefore, it is possible to reliably determine the abnormality from the state in which the refrigerant has escaped to some extent, and to protect the motor coil and the compression mechanism of the compressor 8 from excessive temperature rise.

  Next, another control example of the air conditioner according to the present embodiment will be described with reference to the flowchart of FIG.

  When the processing of the air conditioner is started, it is determined whether the compressor 8 is operating. If the compressor 8 is operating, the timer count set at time T1 is set and the timer count set at time T2 is set. The opening degree EXP of the electric expansion valve 15 is stored in the outdoor control device 13. When the current opening EXP is smaller than the set value exp4, normal operation is performed, and when the current opening EXP is larger than the set value exp4, the current frequency CompHz of the compressor 8 is stored in the outdoor control device 13. When the current frequency CompHz is smaller than the set operation frequency Hz4, normal operation is performed. When the current frequency CompHz is greater than the set operation frequency Hz4, the opening degree EXP and the frequency CompHz are respectively set until the time T1 becomes equal to or greater than the predetermined time Ts4. When the state larger than the set value is continued, the discharge temperature Td detected by the discharge temperature sensor 14 is stored in the outdoor control device 13.

When the state in which the opening degree EXP and the frequency CompHz are continuously larger than the set value and the set operation frequency cannot be maintained continuously, the operation is performed again by resetting the time T1.

Next, when the current discharge temperature Td is smaller than the set value t4, the opening degree EXP, the frequency CompHz, the discharge temperature Td until the time T2 becomes equal to or greater than the predetermined time Ts5 when the current discharge temperature Td is larger than the set value t4. When the state continues larger than the set value and the set operating frequency, the compressor 8 is stopped. If the opening EXP, the frequency CompHz, and the discharge temperature Td cannot be maintained higher than the set value and the set operating frequency, the operation is continued until the predetermined time Ts5 is reached. With the compressor 8 stopped, the indoor control device 7 and the outdoor control device 13 store the refrigerant missing abnormality.

As described above, in this control example, even when the refrigerant is normally removed to some extent, the electric expansion valve 15 is opened to lower the discharge temperature, and the refrigeration cycle such as the compressor 8 does not become abnormal. When the outdoor load is high, etc., it is configured to prevent false detection by judging abnormality when the expansion valve opening, discharge temperature, and compressor frequency are higher than the set value and set operating frequency for a certain period of time. And by memorizing that an abnormality has occurred in the indoor control device 7 and the outdoor control device 13, for example, if an abnormality occurs four times in one hour, by not operating the air conditioner again, The motor coil and compressor parts of the compressor 8 can be protected from excessive temperature rise.

  Further, when it is determined that the refrigeration cycle is abnormal and the compressor 8 is stopped, if an abnormal code indicating that the refrigerant is insufficient is transmitted to the indoor unit 1 of the air conditioner, the user in the room is informed that the refrigerant is insufficient. Announcements can be made promptly.

  As described above, the air conditioner according to the present invention can appropriately determine the abnormality of the refrigeration cycle, and can be applied to various domestic and commercial air conditioners.

DESCRIPTION OF SYMBOLS 1 Indoor unit 2 Outdoor unit 3 Indoor heat exchanger 4 Indoor fan 5 Fan motor 6 Temperature sensor 7 Indoor control apparatus 8 Compressor 9 Four way valve 10 Outdoor heat exchanger 11 Outdoor air temperature sensor 12 Outdoor fan 13 Outdoor control apparatus (memory | storage means)
14 Discharge temperature sensor (Discharge temperature detection means)
15 Electric expansion valve (expansion valve)

Claims (5)

A refrigeration cycle formed by sequentially connecting a compressor, a four-way valve, an outdoor heat exchanger, a variable flow rate expansion valve, and an indoor heat exchanger, and an outdoor fan arranged in the vicinity of the outdoor heat exchanger; An indoor fan disposed in the vicinity of the indoor heat exchanger, discharge temperature detection means for detecting the discharge temperature of the refrigeration cycle, and storage means for storing the throttle opening and discharge temperature of the expansion valve, An air conditioner characterized in that the compressor is stopped when a throttle opening degree of the expansion valve is equal to or greater than a set value and a discharge temperature is equal to or greater than a discharge temperature set value. A refrigeration cycle formed by sequentially connecting a compressor, a four-way valve, an outdoor heat exchanger, a variable flow rate expansion valve, and an indoor heat exchanger, and an outdoor fan arranged in the vicinity of the outdoor heat exchanger; Storing an indoor fan disposed in the vicinity of the indoor heat exchanger, discharge temperature detecting means for detecting the discharge temperature of the refrigeration cycle, throttle opening and discharge temperature of the expansion valve, and operating frequency of the compressor Storage means for performing the compression when the throttle opening of the expansion valve is equal to or higher than a set value, the discharge temperature is equal to or higher than the discharge temperature set value, and the operating frequency of the compressor is equal to or higher than the set operating frequency. An air conditioner characterized by stopping the machine. The air conditioner according to claim 1, wherein the compressor is stopped when the throttle opening of the expansion valve is equal to or greater than a set value and the discharge temperature is equal to or greater than a set value for a predetermined time. . Stop the compressor when the throttle opening of the expansion valve is equal to or higher than the set value, the discharge temperature is equal to or higher than the discharge temperature set value, and the compressor operating frequency is equal to or higher than the set operating frequency for a predetermined time. The air conditioner according to claim 2, wherein The air conditioner according to claim 4, wherein when the compressor is stopped, an abnormal code indicating insufficient refrigerant is transmitted to the indoor unit of the air conditioner.

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