JP2001141341A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner in which moisture in a refrigeration cycle can be removed and molecular sieves can be protected against fracture. SOLUTION: In a refrigeration cycle, a bypass circuit having a dryer 13 provided with molecular sieves 11 in the central part and a filter or filters 12 for capturing foreign matters, e.g. dust or metal powder, in front and rear or on one side thereof is provided between an outdoor heat exchanger 4 and an expansion valve or a capillary tube 8. Furthermore, a calendar detection means 16 for measuring the time of every day, means 17 for switching a refrigerant circuit to the bypass circuit side in response to a signal from the calendar detection means 16 when a predetermined time is measured, and means for switching back the refrigerant circuit in response to a signal when the time elapsed after switching to the bypass circuit reaches a predetermined value are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heat pump type air conditioner.

[0002]

2. Description of the Related Art The production and use of refrigerants that are capable of depleting the ozone layer among the refrigerants that are working media used in air conditioners until now are being restricted internationally in order to protect the earth's ozone layer. Efforts are being made to change to environmentally safe properties.

[0003] In order to actually use some of the selected refrigerants in the refrigeration cycle, it is necessary that these refrigerants be compatible with refrigeration oil required for lubrication of the compressor. As the suitable conditions, it is necessary to be mutually soluble with the refrigerant, to be chemically stable, and to have high electric insulation.

Conventionally used refrigerating machine oils such as mineral oil and alkyl benzene have a small hygroscopicity, so that a small amount of water penetrates into the system and the performance required for a dryer is small. In the case of mineral oil, alkyl benzene and the like, hydrolysis occurs. As a result, no acid is basically generated in the refrigeration cycle by hydrolysis.

However, conventionally used mineral oils, alkylbenzenes, and the like have poor compatibility with alternative refrigerants, and it is difficult to apply them to alternative refrigerants in consideration of the return of refrigerating machine oil to the compressor. The refrigerating machine oil satisfying the above conditions has, for example, a drawback that it has high hygroscopicity and is easily hydrolyzed like ester-based refrigerating machine oil.

[0006] When a refrigerant having a capability of depleting the ozone layer is produced and produced as a working medium that has been used in air conditioners up to now, outside air enters into the inside, and refrigeration oil in the air conditioner absorbs moisture. At the time of installation, rain and dew may enter the pipes that have been left unattended. The amount of water penetration
Currently not managed.

As described above, the following problems occur in the case of ester-based refrigerating machine oil due to the infiltration of water, which impairs the reliability of the air conditioner.

That is, since ester-based refrigerating machine oil is obtained by removing water from the reaction between an acid and an alcohol, if there is water in the refrigeration cycle, a hydrolysis reaction occurs to generate an acid, and further hydrolysis proceeds. Due to its characteristics, it leads to a very serious situation.

In other words, the acid reacts with the metal in the refrigeration cycle to form a metal carboxylate. The metal carboxylate is clogged in various places and reduces reliability. For example, when the metal carboxylate is produced,
This causes clogging of a capillary tube or the like, a decrease in the amount of circulating refrigerant, a shortage of cooling capacity, and furthermore, a failure of the compressor.

Conventionally, in order to cope with these problems, infiltration of water into the refrigeration cycle at the time of production is prevented so as to keep the temperature below a certain value. As a means of capturing water, a dryer filled with synthetic zeolite that adsorbs moisture is placed beforehand in the air conditioner cycle.To check the amount of water, it discolors in response to water, such as sight glass provided in a refrigerant pipe. When using ester-based refrigerating machine oil, for example, when using an ester-based refrigerating machine oil, for example, an acid-moisture scavenger or a hydrolysis inhibitor is added to the refrigerating machine oil to suppress the hydrolysis itself, and the generated acid is trapped in the acid. It was common to take measures such as reacting with an agent to suppress the amount of acid.

A switching valve is provided in the middle of a refrigeration cycle as described in JP-A-8-86544,
The desiccant-containing container and the like are connected through the switching valve, and the desiccant-containing container and the like can be separated from the refrigeration cycle by opening and closing the valve.

Hereinafter, the conventional refrigeration cycle will be described with reference to the drawings. FIG. 9 is a refrigeration cycle diagram of a conventional air conditioner. 9, 101 is a compressor, 102 is an outdoor unit heat exchanger, 103 is an indoor unit heat exchanger, 104 is a decompressor, 105 is a container containing a desiccant 106, 107 is a four-way valve, and 108a and 108b are services. A valve 109 is a flare joint, 110a and 110b are pipes connecting the outdoor unit and the indoor unit, and the apparatus is operated with the service valves 108a and 108b opened for removing moisture, and the refrigerant is stored in the container 105 containing the desiccant 106. When it is determined that the water has been removed after a certain period of time, the operation is stopped and the service valves 108a and 108b are closed,
The configuration is such that the container containing the desiccant can be removed from the service valves 108a and 108b.

[0013]

However, in the above-mentioned conventional configuration, it is impossible to adsorb moisture in the system to the desiccant 106 by the desiccant 106 in the air conditioning operation which is the original purpose of the air conditioner. In order to adsorb moisture to the desiccant 106, it is necessary to perform the operation separately from the air conditioning operation. Further, when the desiccant-containing container 105 is opened and connected by a pipe between the service valves 108a and 108b, more moisture is adsorbed to the desiccant 106 in terms of the opening time of the desiccant-containing container 105 and the opening time of the piping. There was a possibility.

SUMMARY OF THE INVENTION The present invention solves the conventional problems and prevents the capillary tube from being clogged by removing water in the refrigeration cycle in parallel with the air conditioning operation of a commercial air conditioner and the like, and further destroys the desiccant. It is an object of the present invention to provide an air conditioner that prevents an increase in the amount of blockage of a capillary tube due to the above, and prevents abrasive wear of a compressor.

[0015]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention relates to a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like, which are sequentially connected by refrigerant piping. In the cycle in which the refrigerant is circulated, a molecular sieve is provided in the center between the outdoor heat exchanger and the expansion valve or the capillary tube, and a filter for capturing foreign matter such as dust and metal powder is provided before and / or after the molecular sieve. A bypass circuit having a dryer, a calendar detecting means for measuring daily time, and a switching means for switching to a bypass circuit for switching the refrigerant circuit to the bypass circuit side by a signal from the calendar detecting means when the time reaches a predetermined time; , The elapsed time since switching to the bypass circuit is measured, and when that time reaches a predetermined value, It is provided with a switching means to the refrigerant circuit returns to the refrigerant circuit of Rimoto.

The present invention also provides a cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate the refrigerant. A bypass circuit is provided between the heat exchanger and the expansion valve or the capillary tube, which has a molecular sieve in the center and a dryer provided with a filter for capturing foreign matter such as dust and metal powder before and / or after the molecular sieve. To an air conditioner operating time measuring means for measuring the operating time of the air conditioner main body, and to a bypass circuit for switching the refrigerant circuit to the bypass circuit side by a signal from the air conditioner operating time measuring means when the operating time reaches a predetermined value. And the elapsed time since switching to the bypass circuit is measured, and when the time reaches a predetermined value, A switching circuit for returning to the refrigerant circuit, an air conditioner operating time integrating means for calculating a total value of operating times detected by the air conditioner operating time measuring means, and a bypass circuit side by the air conditioner operating time integrating means. The switching means for switching to the bypass circuit which determines whether or not to switch to the bypass circuit and stops the switching to the bypass circuit when the time reaches a predetermined value is provided.

The present invention also relates to a cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator and the like are sequentially connected by a refrigerant pipe to circulate the refrigerant. Air conditioning is provided between the heat exchanger and the expansion valve or the capillary tube, and a bypass circuit having a molecular sieve in the center and a dryer in front and / or behind which is provided with a filter for capturing foreign matter such as dust and metal powder. During the time T (t) determined by the accumulated time t from the installation of the air conditioner, the refrigerant flows through the bypass circuit for the time T (t) after a predetermined time from the start of the operation of the air conditioner, and the accumulated time When t exceeds a predetermined time, the bypass circuit is not switched to the bypass circuit. And those having a circuit switching means for switching the normal refrigerant circuit.

The present invention also relates to a cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator and the like are sequentially connected by a refrigerant pipe to circulate the refrigerant. Air conditioning is provided between the heat exchanger and the expansion valve or the capillary tube, and a bypass circuit having a molecular sieve in the center and a dryer in front and / or behind which is provided with a filter for capturing foreign matter such as dust and metal powder. During the time T (t) determined by the accumulated time t from the installation of the air conditioner, the refrigerant flows through the bypass circuit for the time T (t) after a predetermined time from the start of the operation of the air conditioner, and the accumulated time When t exceeds a predetermined time, the refrigerant circuit control means for fixing the switching time to the bypass circuit to a predetermined value and a signal from the refrigerant circuit control means. And it has a circuit switching means for switching the bypass circuit and the normal of the refrigerant circuit.

According to these inventions, prevention of blockage of the capillary tube by removing moisture in the refrigeration cycle of the air conditioner during air-conditioning operation, and prevention of increase in the amount of blockage of the capillary tube due to destruction of the desiccant, and An air conditioner that prevents the abrasive wear of the compressor is obtained.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is to connect a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like in order by a refrigerant pipe. In the cycle in which the refrigerant is circulated, a molecular sieve is provided in the center between the outdoor heat exchanger and the expansion valve or the capillary tube, and a filter for capturing foreign matter such as dust and metal powder is provided before and / or after the molecular sieve. A bypass circuit having a dryer, a calendar detecting means for measuring daily time, and a switching means for switching to a bypass circuit for switching the refrigerant circuit to the bypass circuit side by a signal from the calendar detecting means when the time reaches a predetermined time; , The elapsed time since switching to the bypass circuit is measured, and when the time reaches a predetermined value, A switching means for switching to a refrigerant circuit for returning to the refrigerant circuit is provided.When a predetermined time is reached every day, the refrigerant circuit is switched to the bypass circuit side, and after a predetermined time elapses, the refrigerant is returned to the original circuit. , The powdered molecular sieves in the dryer can be suppressed. Further, since the switching control of the refrigerant circuit uses a calendar, the control is very simple.

According to a second aspect of the present invention, a refrigerant is circulated by sequentially connecting a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like through a refrigerant pipe. In the cycle, a bypass is provided between the outdoor heat exchanger and the expansion valve or the capillary tube, in which a molecular sieve is provided at a central portion, and a dryer provided with a filter for capturing foreign matter such as dust and metal powder is provided before and / or after the molecular sieve. An air conditioner operating time measuring means for measuring the operating time of the air conditioner body, and a bypass circuit for the refrigerant circuit by a signal from the air conditioner operating time measuring means when the operating time reaches a predetermined value. The switching means for switching to the bypass circuit, and the elapsed time since switching to the bypass circuit is measured, and the time is determined by a predetermined value. Air conditioner operating time integrating means for calculating the total value of the operating time detected by the air conditioner operating time measuring means, the air conditioner operating time integrating means, and the air conditioner operating time. The switching means for switching to the bypass circuit, which determines whether or not the switching to the bypass circuit is performed by the integrating means and stops the switching to the bypass circuit when the time reaches a predetermined value, is provided. When the time reaches a predetermined time, the refrigerant circuit is switched to the bypass circuit side, and the refrigerant circuit is returned to the original circuit after the predetermined time elapses in the bypass circuit, so that the refrigerant does not pass through the dryer more than necessary. Water is removed by the molecular sieves adsorbing moisture when the refrigerant circuit of the air conditioner is switched to the bypass circuit. Possible it is.

Further, when the operation time of the air conditioner reaches a predetermined value, the switching to the bypass circuit is stopped, so that the refrigerant does not pass through the dryer, so that the molecular sieves in the dryer are not powdered by the passage of the refrigerant. Further, the molecular sieve powder remaining in the dryer does not flow out into the system because there is no switching to the bypass circuit, the capillary clogging due to the molecular sieve powder increases, and the molecular sieve powder flows into the compressor. Abrasive wear and the like of the sliding member can be prevented.

According to a third aspect of the present invention, the refrigerant is circulated by sequentially connecting a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like via a refrigerant pipe. In the cycle, a bypass is provided between the outdoor heat exchanger and the expansion valve or the capillary tube, in which a molecular sieve is provided at a central portion, and a dryer provided with a filter for capturing foreign matter such as dust and metal powder is provided before and / or after the molecular sieve. A circuit is provided, and the time T (t) determined by the integrated time t of the air conditioner operation
During a predetermined time after the start of the operation of the air conditioner,
(T) The refrigerant is caused to flow through the bypass circuit for a period of time, and when the integrated time t exceeds a predetermined time, switching to the bypass circuit is not performed. It has circuit switching means for switching the normal refrigerant circuit. When the operation time t of the air conditioner reaches a predetermined time, the refrigerant circuit is switched to the bypass circuit side, and after the passage of T (t) in the bypass circuit, the refrigerant circuit is switched. By returning the air to the original circuit, the refrigerant does not pass through the dryer more than necessary, so that the molecular sieves in the dryer can be suppressed from pulverizing.When the refrigerant circuit for air conditioner operation switches to the bypass circuit, the molecular sieve The water can be removed by adsorbing the water.

Further, when the accumulated operation time of the air conditioner exceeds a predetermined value, the switching to the bypass circuit is stopped, so that the refrigerant does not pass through the dryer, so that the molecular sieves in the dryer are not powdered by the passage of the refrigerant. . In addition, since the amount of water adsorbed on the molecular sieve gradually decreases in the initial stage, the switching time to the bypass circuit is shortened by the refrigerant circuit control means, thereby suppressing the time for the refrigerant to pass between the molecular sieves more than necessary. Therefore, powdering of molecular sieves can be suppressed.

Further, the molecular sieve powder remaining in the dryer does not flow out into the system because there is no switching to the bypass circuit, the clogging of the capillary by the molecular sieve powder increases, and the molecular sieve powder flows into the compressor. By doing so, it is possible to prevent abrasive wear and the like of the sliding member.

According to a fourth aspect of the present invention, a refrigerant is circulated by sequentially connecting a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like via a refrigerant pipe. In the cycle, a bypass is provided between the outdoor heat exchanger and the expansion valve or the capillary tube, in which a molecular sieve is provided at a central portion, and a dryer provided with a filter for capturing foreign matter such as dust and metal powder is provided before and / or after the molecular sieve. A circuit is provided, and the time T (t) determined by the integrated time t of the air conditioner operation
During a predetermined time after the start of the operation of the air conditioner,
(T) a signal from the refrigerant circuit control means and the refrigerant circuit control means for causing the refrigerant to flow through the bypass circuit during the time and fixing the switching time to the bypass circuit to a predetermined value when the integrated time t exceeds the predetermined time; When the operation time t of the air conditioner reaches a predetermined time, the refrigerant circuit is switched to the bypass circuit side, and T (t) is set in the bypass circuit.
By returning the refrigerant circuit to the original circuit after the lapse of time, the refrigerant does not pass through the dryer more than necessary, so that the molecular sieves in the dryer can be suppressed from being powdered, and the refrigerant circuit for operating the air conditioner is connected to the bypass circuit. The water can be removed by the adsorption of the water by the molecular sieve at the time of switching.

Also, since the amount of water adsorbed on the molecular sieve gradually decreases in the initial stage, the switching time to the bypass circuit is shortened by the air conditioner operating time integrating means, so that the refrigerant is unnecessarily discharged between the molecular sieves. Can reduce the time required for the molecular sieves to pass through.

Further, when the integrated operation time of the air conditioner reaches a predetermined time, the switching time to the bypass circuit is fixed to a short time, so that the refrigerant passes through the dryer for a short predetermined time. Due to the passage of the refrigerant, the amount of the powder is suppressed to a small level, and the water gradually coming out of the compressor can be adsorbed.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the air conditioner of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a refrigeration cycle diagram of an air conditioner according to Embodiment 1 of the present invention, and FIG. 2 is a flowchart showing the operation of the air conditioner of the embodiment. In the figure, an air conditioner 1 constitutes a cycle in which a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, a pipe 5, and an indoor heat exchanger 6 are connected in a ring by pipes to circulate a refrigerant reversibly. Before and after the indoor heat exchanger 6, a liquid-side opening / closing electromagnetic valve 7 composed of, for example, an electromagnetic valve, and a throttle mechanism 8, such as an indoor-side capillary tube,
The gas side opening / closing solenoid valve 9 is interposed.

An accumulator 10 is provided behind the indoor heat exchanger 6, and the accumulator 10 is connected to the compressor 2 by piping. Further, between the outdoor heat exchanger 4 and the pipe 5, a molecular sieve 11 is filled in a central portion as a bypass circuit, and a filter 12 for capturing foreign matter such as dust and metal powder is provided before and / or after the molecular sieve 11. The dryer 13 is provided via two three-way valves 14 and 15.

Reference numeral 16 denotes calendar detecting means for detecting the date and time of the day, and reference numeral 17 denotes a refrigerant circuit switching means for operating the three-way valves 14 and 15 based on a signal from the calendar detecting means 16. Reference numeral 18 denotes a throttle mechanism such as an outdoor capillary tube. The compressor 2 is filled with an ester oil having good compatibility with the HFC-based refrigerant.
407C (R32 / R125 / R134a = 23wt%
/ 25 wt% / 52 wt%).

The operation of the air conditioner configured as described above will be described.

When the air conditioner 1 of this embodiment is operated,
The refrigerant is compressed to a high-temperature and high-pressure state by the compressor 2 and the four-way valve 3, liquefied in the outdoor heat exchanger 4, and reaches the indoor heat exchanger 6 through a throttle mechanism 8 such as an indoor capillary tube.
After the refrigerant removes heat from the surrounding air and evaporates in the indoor heat exchanger 6, the refrigerant passes through the accumulator 10 and is compressed.
The air conditioning by cooling is performed by performing the circulation of returning to.

According to the present embodiment, the following operations are performed to remove water from the air conditioner 1, prevent the molecular sieve 11 from being powdered, a throttle mechanism 8 such as an indoor capillary tube, and a throttle mechanism such as an outdoor capillary tube. 18 can be prevented from clogging.

That is, in the cooling operation, for example, the refrigerant is compressed by the compressor 2 to a high temperature and high pressure state and
The R407C liquefied in the above circulates through the pipe 5, the throttle mechanism 8, such as the indoor side capillary tube, the indoor heat exchanger 6, and the accumulator 10, and returns to the compressor 2. At this time, R40
7C evaporates in the indoor heat exchanger 6, deprives the room of heat and cools the room.

In this cycle, the calendar detecting means 16 detects the time at that time, and when the predetermined time comes, a signal is sent to the refrigerant circuit switching means 17 as shown in steps 2 and 3, and the refrigerant circuit switching means 17 Moves the three-way valves 14 and 15 to change the refrigerant circuit to the bypass circuit side.

Thus, the refrigerant passes through the outdoor heat exchanger 4, passes through the dryer 13 via the three-way valve 14, and is contained in the refrigerant and the refrigerating machine oil by the molecular sieves 11 filled in the dryer 13. Moisture is adsorbed.

Further, as shown in step 4, when the calendar detecting means 16 detects the next predetermined time, a signal is sent to the refrigerant circuit switching means 17, and the refrigerant circuit switching means 17 moves the three-way valves 14 and 15 and the refrigerant circuit Is returned from the bypass circuit, and the refrigerant circulates through the refrigerant circuit without the dryer 13.

As a result, the water in the refrigerant circuit is adsorbed by the molecular sieves 11 filled in the dryer 13, and the water in the refrigerant circuit is reduced. Blockage of the throttle mechanisms 8, 18 such as a capillary tube by the metal carboxylate generated by decomposition can be prevented.

Further, by using the bypass circuit, the refrigerant does not pass through the dryer 13 more than necessary, so that the molecular sieves 11 in the dryer 13 can be suppressed from being powdered. Abrasion of the sliding material and the carboxylate metal salt are deposited on the squeezing mechanisms 8 and 18 such as a capillary tube, or the squeezing mechanism of a capillary tube or the like due to trapped powder of the molecular sieves 11 in the carboxylate metal salt. The clogging of 8, 18 can be prevented. Further, since the switching control of the refrigerant circuit uses a daily calendar, an effect that the control is very simple can be obtained.

(Embodiment 2) FIG. 3 is a refrigeration cycle diagram of an air conditioner according to Embodiment 2 of the present invention, and FIG. 4 is a flowchart showing the operation of the air conditioner of the embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In FIGS. 3 and 4, reference numeral 19 denotes an air conditioner operating time detecting means for detecting an elapsed time from the start of operation of the air conditioner, and reference numeral 20 denotes an air conditioner operating time detecting means 1.
Refrigerant circuit switching means for operating the three-way valves 14 and 15 in response to the signal 9.

The operation of the air conditioner configured as described above will be described.

When the air conditioner 1 of this embodiment is operated,
The refrigerant is compressed to a high-temperature and high-pressure state by the compressor 2 and the four-way valve 3, liquefied in the outdoor heat exchanger 4, and reaches the indoor heat exchanger 6 through a throttle mechanism 8 such as an indoor capillary tube.
After the refrigerant removes heat from the surrounding air and evaporates in the indoor heat exchanger 6, the refrigerant passes through the accumulator 10 and is compressed.
The air conditioning by cooling is performed by performing the circulation of returning to.

According to the present embodiment, the following operations are performed to remove moisture in the air conditioner 1, prevent the molecular sieve 11 from being powdered, a throttle mechanism 8 such as an indoor capillary tube, and a throttle mechanism such as an outdoor capillary tube. 18 can be prevented from clogging.

That is, in the cooling operation, for example, the refrigerant is compressed by the compressor 2 to a high temperature and high pressure state, and
The R407C liquefied in the above circulates through the pipe 5, the throttle mechanism 8, such as the indoor side capillary tube, the indoor heat exchanger 6, and the accumulator 10, and returns to the compressor 2. At this time, R40
7C evaporates in the indoor heat exchanger 6, deprives the room of heat and cools the room.

In this cycle, as shown in step 3, the air conditioner operation time detecting means 19 detects the elapsed time since the start of the operation of the air conditioner 1, and when a predetermined time has elapsed, the operation proceeds to step 4 As shown in the above, the air conditioner operation time detecting means 19 sends a signal to the refrigerant circuit switching means 20, and the refrigerant circuit switching means 20 operates the three-way valves 14, 15 to change the refrigerant circuit to the bypass circuit side.

Thus, the refrigerant passes through the outdoor heat exchanger 4, passes through the dryer 13 via the three-way valve 14, and is contained in the refrigerant and the refrigerating machine oil by the molecular sieves 11 filled in the dryer 13. Moisture is adsorbed.

As shown in step 5, when the air conditioner operating time detecting means 19 detects that a predetermined time has elapsed since the refrigerant circuit of the air conditioner 1 was switched to the bypass circuit, this is detected by the refrigerant circuit. A signal is sent to the switching means 20, and the refrigerant circuit switching means 20 operates the three-way valves 14 and 15 to switch the refrigerant circuit from the bypass circuit to the normal circuit,
The refrigerant circulates through the refrigerant circuit without the dryer 13.

As a result, the water in the refrigerant circuit is adsorbed by the dryer 13 and the water in the refrigerant circuit is reduced.
Hydrolysis of the refrigerating machine oil can be suppressed, and blockage of the restricting mechanisms 8, 18 such as a capillary tube by the metal carboxylate generated by the decomposition of the refrigerating machine oil can be prevented.

Further, since the refrigerant does not pass through the dryer 13 more than necessary by using the bypass circuit, the molecular sieves 11 in the dryer 13 can be suppressed from being powdered. Abrasion of the sliding material and the carboxylate metal salt are deposited on the squeezing mechanisms 8 and 18 such as a capillary tube, or the squeezing mechanism of a capillary tube or the like due to trapped powder of the molecular sieves 11 in the carboxylate metal salt. The clogging of 8, 18 can be prevented.

When the operation time of the air conditioner 1 reaches a predetermined time, the refrigerant circuit is switched to the bypass circuit side, and after a predetermined time has passed in the bypass circuit, the refrigerant circuit is returned to the normal circuit. , The powdering of the molecular sieve 11 in the dryer 13 can be suppressed, and the molecular sieve 11 adsorbs moisture when the refrigerant circuit of the air conditioner 1 is switched to the bypass circuit, thereby removing moisture. It is possible.

Further, when the operation time of the air conditioner 1 reaches a predetermined value, the switching to the bypass circuit is stopped, so that the refrigerant does not pass through the dryer 13, so that the molecular sieves 11 in the dryer 13 are powdered by the passage of the refrigerant. Is not converted.
Further, the molecular sieve 11 powder remaining in the dryer 13 does not flow into the system because there is no switching to the bypass circuit, and the clogging of the capillary tube due to the molecular sieve 13 powder increases, and the molecular sieve 13 powder is compressed. 2 can be prevented from abrasion of the sliding member due to flowing into the inside of the sliding member.

(Embodiment 3) FIG. 5 is a refrigeration cycle diagram of an air conditioner according to Embodiment 3 of the present invention, and FIG. 6 is a flowchart showing the operation of the air conditioner of the embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In FIGS. 5 and 6, reference numeral 21 denotes a refrigerant circuit control means for detecting an elapsed time from the start of operation of the air conditioner and determining a time for the refrigerant to flow through the bypass circuit. Reference numeral 22 denotes a refrigerant circuit control means. Three-way valve 1 according to signal 21
This is a refrigerant circuit switching means for performing operations of 4, 15.

The operation of the system configured as described above will be described.

When the air conditioner 1 of the present invention is operated, the refrigerant is compressed to a high temperature and high pressure state by the compressor 2 and the four-way valve 3 and liquefied in the outdoor heat exchanger 4, and a throttle mechanism 8 such as an indoor capillary tube. To the indoor heat exchanger 6. After the refrigerant takes heat from the surrounding air and evaporates in the indoor heat exchanger 6, the refrigerant passes through the accumulator 10 and returns to the compressor 2 so as to perform air conditioning by cooling.

According to the present embodiment, the following operations are performed to remove moisture in the air conditioner 1, prevent the molecular sieve 11 from being powdered, a throttle mechanism 8 such as an indoor capillary tube, and a throttle mechanism such as an outdoor capillary tube. 18 can be prevented from clogging.

That is, for example, in the case of the cooling operation, the refrigerant is compressed to a high temperature and a high pressure state by the compressor 2 and the outdoor heat exchanger 4
The R407C liquefied in the above circulates through the pipe 5, the throttle mechanism 8, such as the indoor side capillary tube, the indoor heat exchanger 6, and the accumulator 10, and returns to the compressor 2. At this time, R40
7C evaporates in the indoor heat exchanger 6, deprives the room of heat and cools the room.

In this cycle, as shown in steps 2 and 3, the refrigerant circuit control means 21 detects the elapsed time from the start of the operation of the air conditioner 1, and when this operation time reaches a predetermined time, As shown in steps 4 and 5, the refrigerant circuit control means 21 sets the time T for switching to the bypass circuit side based on the accumulated operation time t after the air conditioner 1 starts operating.
(T) is calculated.

Then, the refrigerant circuit control means 21 sends a signal to the refrigerant circuit switching means 22, and the refrigerant circuit switching means 22 operates the three-way valves 14, 15 to change the refrigerant circuit to the bypass circuit side. As a result, the refrigerant passes through the outdoor heat exchanger 4, passes through the dryer 13 via the three-way valve 14, and adsorbs moisture contained in the refrigerant and the refrigerating machine oil by the molecular sieves 11 filled in the dryer 13. Is done.

Next, as shown in Steps 6 and 7, when the refrigerant circuit control means 21 detects that the elapsed time from the switching of the refrigerant circuit of the air conditioner 1 to the bypass circuit reaches the predetermined time T (t). A signal is sent to the refrigerant circuit switching means 20, and the refrigerant circuit switching means 20 operates the three-way valves 14, 15 to return the refrigerant circuit from the bypass circuit, and the refrigerant circulates in the refrigerant circuit without the dryer 13.

Further, as shown in steps 8 and 9, the refrigerant circuit control means 21 detects an integrated operation time t after the air conditioner 1 is installed and starts operation, and the integrated operation time t is set to a predetermined integrated operation time. If the time is exceeded, the switching time to the bypass circuit is set to 0 hour.

As a result, the water in the refrigerant circuit is adsorbed by the dryer 13 and the water in the refrigerant circuit is reduced.
Hydrolysis of the refrigerating machine oil can be suppressed, and blockage of the restricting mechanisms 8, 18 such as a capillary tube by the metal carboxylate generated by the decomposition of the refrigerating machine oil can be prevented.

Further, when the integrated operation time of the air conditioner 1 reaches a predetermined time, the refrigerant circuit is switched to the bypass circuit side, and the refrigerant circuit is returned to the original circuit after the predetermined time has passed in the bypass circuit, so that the refrigerant becomes unnecessary. Since the powder does not pass through the dryer 13, powdering of the molecular sieves 11 in the dryer 13 can be suppressed.

As a result, the abrasive wear of the sliding material of the compressor 2 due to the crushed powder and the metal carboxylate precipitate on the drawing mechanisms 8 and 18 such as a capillary tube, and the molecular sieve 11 is damaged by the metal carboxylate. The air conditioner 1 can prevent clogging of the throttle mechanisms 8 and 18 such as a capillary tube due to trapped powder.
When the operation refrigerant circuit is switched to the bypass circuit, the molecular sieve 11 adsorbs the water, so that the water can be removed.

Further, when the accumulated operation time of the air conditioner 1 reaches a predetermined value, the switching to the bypass circuit is stopped, so that the refrigerant does not pass through the dryer 13, so that the molecular sieves 11 in the dryer 13 are powdered by the passage of the refrigerant. Is not converted.

Further, the molecular sieve 11 powder remaining in the dryer 13 does not flow into the system because there is no switching to the bypass circuit, and the clogging of the capillary tube due to the molecular sieve 13 powder increases.
The effect is obtained that it is possible to prevent the abrasive wear of the sliding material due to the flow of the molecular sieves 13 powder into the compressor 2.

(Embodiment 4) FIG. 7 is a refrigeration cycle diagram of an air conditioner according to Embodiment 4 of the present invention, and FIG. 8 is a flowchart of the air conditioner of the embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In FIGS. 7 and 8, reference numeral 23 denotes a refrigerant circuit control means for detecting an elapsed time from the start of operation of the air conditioner and determining a time for the refrigerant to flow through the bypass circuit. Reference numeral 24 denotes a refrigerant circuit control means. Refrigerant circuit switching means for operating the three-way valves 14 and 15 in accordance with the signal 23.

The operation of the air conditioner configured as described above will be described.

When the air conditioner 1 of this embodiment is operated,
The refrigerant is compressed to a high-temperature and high-pressure state by the compressor 2 and the four-way valve 3, liquefied in the outdoor heat exchanger 4, and reaches the indoor heat exchanger 6 through a throttle mechanism 8 such as an indoor capillary tube.
After the refrigerant removes heat from the surrounding air and evaporates in the indoor heat exchanger 6, the refrigerant passes through the accumulator 10 and is compressed.
The air conditioning by cooling is performed by performing the circulation of returning to.

According to the present embodiment, the following operations are performed to remove moisture from the air conditioner 1, prevent the molecular sieve 11 from being powdered, a throttle mechanism 8 such as an indoor capillary tube, and a throttle mechanism such as an outdoor capillary tube. 18 can be prevented from clogging.

That is, for example, in the case of the cooling operation, the refrigerant is compressed by the compressor 2 to a high-temperature and high-pressure state and the outdoor heat exchanger 4
The R407C liquefied in the above circulates through the pipe 5, the throttle mechanism 8, such as the indoor side capillary tube, the indoor heat exchanger 6, and the accumulator 10, and returns to the compressor 2. At this time, R40
7C evaporates in the indoor heat exchanger 6, deprives the room of heat and cools the room.

In this cycle, as shown in steps 2 and 3, the refrigerant circuit control means 23 detects the elapsed time from the start of the operation of the air conditioner 1, and when this operation time reaches a predetermined time, As shown in steps 4 and 5, the refrigerant circuit control means 23 calculates the switching time T (t) to the bypass circuit side based on the integrated operation time t from the start of the operation of the air conditioner 1. Then, the refrigerant circuit control means 23 sends a signal to the refrigerant circuit switching means 24, and the refrigerant circuit switching means 24 operates the three-way valves 14, 15 to change the refrigerant circuit to the bypass circuit side.

Thus, the refrigerant passes through the outdoor heat exchanger 4, passes through the dryer 13 via the three-way valve 14, and is contained in the refrigerant and the refrigerating machine oil by the molecular sieves 11 filled in the dryer 13. Moisture is adsorbed.

Next, as shown in steps 6 and 7, when the refrigerant circuit control means 23 detects that the elapsed time from the switching of the refrigerant circuit of the air conditioner 1 to the bypass circuit reaches the predetermined time T (t). A signal is sent to the refrigerant circuit switching means 24, and the refrigerant circuit switching means 24 operates the three-way valves 14, 15 to return the refrigerant circuit from the bypass circuit, and the refrigerant circulates in the refrigerant circuit without the dryer 13.

Further, as shown in steps 8 and 9, the refrigerant circuit control means 23 detects an integrated operation time t after the air conditioner 1 is installed and starts operation, and the integrated operation time t is calculated by a predetermined integration. When the operation time is exceeded, the switching time to the bypass circuit is set to a predetermined time.

As a result, the water in the refrigerant circuit is adsorbed by the dryer 13 and the water in the refrigerant circuit is reduced.
Hydrolysis of the refrigerating machine oil can be suppressed, and blockage of the restricting mechanisms 8, 18 such as a capillary tube by the metal carboxylate generated by the decomposition of the refrigerating machine oil can be prevented.

Further, when the integrated operation time of the air conditioner 1 reaches a predetermined time, the refrigerant circuit is switched to the bypass circuit side, and the refrigerant circuit is returned to the original circuit after the predetermined time has passed in the bypass circuit, so that the refrigerant becomes unnecessary. Since the powder does not pass through the dryer 13, powdering of the molecular sieves 11 in the dryer 13 can be suppressed.

As a result, the abrasive wear of the sliding material of the compressor 2 due to the crushed powder and the metal carboxylate precipitate on the drawing mechanisms 8 and 18 such as the capillary tube, and the molecular sieve 11 is damaged by the metal carboxylate. The clogging of the throttle mechanisms 8 and 18 such as the capillary tube due to the trapping of the powder can be prevented, and the molecular sieve 11 adsorbs moisture when the refrigerant circuit for operating the air conditioner 1 switches to the bypass circuit. Can be removed.

Further, when the integrated operation time of the air conditioner 1 reaches a predetermined value, the switching time to the bypass circuit is fixed.
Since the refrigerant does not pass through the dryer 13 more than necessary, the molecular sieves 11 in the dryer 13 are not powdered by the passage of the refrigerant.

Further, when the accumulated operation time of the air conditioner 1 reaches a predetermined time, the switching time to the bypass circuit is fixed to the predetermined time, so that the refrigerant passes through the dryer 13 for a short predetermined time, so that the molecular sieve in the dryer 13 is removed. Since the amount of the powder is reduced to a small level by the passage of the refrigerant, and is used in the compressor 2, the water 11 can adsorb moisture gradually coming out of the metal material.

[0085]

As described above, according to the first aspect of the present invention,
The invention described in (1) is a cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate the refrigerant, A bypass circuit having a molecular sieve in the center and a dryer provided with a filter for trapping foreign matter such as dust and metal powder is provided between the center and the molecular sieve, and before and / or after the filter. Calendar detecting means to be measured, switching means to a bypass circuit for switching the refrigerant circuit to the bypass circuit side by a signal from the calendar detecting means when the time reaches a predetermined time, and measuring the elapsed time since switching to the bypass circuit. Means for switching to a refrigerant circuit for returning to the original refrigerant circuit by a signal when the time reaches a predetermined value The refrigerant circuit is switched to the bypass circuit side at a predetermined time every day at a predetermined time, and the refrigerant does not pass through the dryer more than necessary to return the refrigerant to the original circuit after the predetermined time elapses. Powdering can be suppressed. Further, since the switching control of the refrigerant circuit uses a calendar, the control is very simple.

The invention according to claim 2 of the present invention provides:
A cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate a refrigerant, and the outdoor heat exchanger and an expansion valve or a capillary tube are circulated. In between, a bypass circuit having a dryer provided with a molecular sieve in the center and a filter for capturing foreign matter such as dust and metal powder is provided before and after or at one of the molecular sieves, and the operation time of the air conditioner body is measured. Air conditioner operating time measuring means, switching means for switching the refrigerant circuit to the bypass circuit by a signal from the air conditioner operating time measuring means when the operating time reaches a predetermined value, and switching to the bypass circuit The elapsed time from the start of the refrigerant circuit is measured, and when the time reaches a predetermined value, the refrigerant circuit returns to the original refrigerant circuit. Switching means and the air conditioner operating time integrating means for calculating the total value of the operating time detected by the air conditioner operating time measuring means and the air conditioner operating time integrating means determine the presence or absence of switching to the bypass circuit side. Switching means for switching to a bypass circuit that stops switching to the bypass circuit when the time reaches a predetermined value, and switches the refrigerant circuit to the bypass circuit side when the operation time of the air conditioner reaches the predetermined time. By returning the refrigerant circuit to the original circuit after a lapse of a predetermined time in the bypass circuit, the refrigerant does not pass through the dryer more than necessary, so that powdering of molecular sieves in the dryer can be suppressed, and the operation of the air conditioner can be suppressed. When the refrigerant circuit is switched to the bypass circuit, water can be removed by the molecular sieve absorbing the water.

Further, when the operation time of the air conditioner reaches a predetermined value, the switching to the bypass circuit is stopped, so that the refrigerant does not pass through the dryer, so that the molecular sieves in the dryer are not powdered by the passage of the refrigerant. Further, the molecular sieve powder remaining in the dryer does not flow out into the system because there is no switching to the bypass circuit, the capillary clogging due to the molecular sieve powder increases, and the molecular sieve powder flows into the compressor. Abrasive wear and the like of the sliding member can be prevented.

The invention according to claim 3 of the present invention provides
A cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate a refrigerant, and the outdoor heat exchanger and an expansion valve or a capillary tube are circulated. In between, a bypass circuit having a dryer provided with a molecular sieve in the center and a filter for capturing foreign matter such as dust and metal powder is provided before and after or in one of the molecular sieves, and is determined by the accumulated time t of the operation of the air conditioner. Time T
During (t), the refrigerant is caused to flow through the bypass circuit for the T (t) time after a predetermined time from the start of the operation of the air conditioner, and when the accumulated time t exceeds the predetermined time, switching to the bypass circuit is performed. A circuit switching means for switching between a bypass circuit and a normal refrigerant circuit in accordance with a signal from the refrigerant circuit control means and a refrigerant circuit control means which does not perform the operation, and bypasses the refrigerant circuit when the operation time t of the air conditioner reaches a predetermined time. By switching to the circuit side and returning the refrigerant circuit to the original circuit after the elapse of T (t) in the bypass circuit, since the refrigerant does not pass through the dryer more than necessary, powdering of molecular sieves in the dryer can be suppressed. Water can be removed by the molecular sieves adsorbing water when the refrigerant circuit for air conditioner operation switches to the bypass circuit.

Further, when the accumulated operation time of the air conditioner exceeds a predetermined value, the switching to the bypass circuit is stopped, so that the refrigerant does not pass through the dryer, so that the molecular sieves in the dryer are not powdered by the passage of the refrigerant. . In addition, since the amount of water adsorbed on the molecular sieve gradually decreases in the initial stage, the switching time to the bypass circuit is shortened by the refrigerant circuit control means, thereby suppressing the time for the refrigerant to pass between the molecular sieves more than necessary. Therefore, powdering of molecular sieves can be suppressed.

Further, the molecular sieve powder remaining in the dryer does not flow into the system because there is no switching to the bypass circuit, so that the clogging of the capillary due to the molecular sieve powder increases, and the molecular sieve powder flows into the compressor. By doing so, it is possible to prevent abrasive wear and the like of the sliding member.

The invention according to claim 4 of the present invention provides:
A cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate a refrigerant, and the outdoor heat exchanger and an expansion valve or a capillary tube are circulated. In between, a bypass circuit having a dryer provided with a molecular sieve in the center and a filter for capturing foreign matter such as dust and metal powder is provided before and after or in one of the molecular sieves, and is determined by the accumulated time t of the operation of the air conditioner. Time T
During (t), the refrigerant is caused to flow through the bypass circuit for the time T (t) after a predetermined time from the start of the operation of the air conditioner, and when the accumulated time t exceeds the predetermined time, the switching time to the bypass circuit is set. And a circuit switching means for switching between a bypass circuit and a normal refrigerant circuit by a signal of the refrigerant circuit control means for fixing the air conditioner to a predetermined value. The refrigerant circuit is switched to the bypass circuit side, and T (t)
By returning the refrigerant circuit to the original circuit after the lapse of time, the refrigerant does not pass through the dryer more than necessary, so that the molecular sieves in the dryer can be suppressed from being powdered, and the refrigerant circuit for operating the air conditioner is connected to the bypass circuit. The water can be removed by the molecular sieve adsorbing the water at the time of switching.

Also, since the amount of water adsorbed on the molecular sieve gradually decreases in the initial stage, the switching time to the bypass circuit is shortened by the air conditioner operation time integrating means, so that the refrigerant is unnecessarily discharged from the molecular sieve. Can reduce the time required for the molecular sieves to pass through.

Further, when the accumulated operation time of the air conditioner reaches a predetermined time, the switching time to the bypass circuit is fixed to a short time, so that the refrigerant passes through the dryer for a short predetermined time. Due to the passage of the refrigerant, the amount of the powder is suppressed to a small level, and the water gradually coming out of the compressor can be adsorbed.

[Brief description of the drawings]

FIG. 1 is a refrigeration cycle diagram of an air conditioner according to Embodiment 1 of the present invention.

FIG. 2 is a flowchart illustrating an operation of the air conditioner according to the first embodiment of the present invention.

FIG. 3 is a refrigeration cycle diagram of an air conditioner according to a second embodiment of the present invention.

FIG. 4 is a flowchart illustrating an operation of the air conditioner according to the second embodiment of the present invention.

FIG. 5 is a refrigeration cycle diagram of an air conditioner according to Embodiment 3 of the present invention.

FIG. 6 is a flowchart illustrating an operation of the air conditioner according to the third embodiment of the present invention.

FIG. 7 is a refrigeration cycle diagram of an air conditioner according to a fourth embodiment of the present invention.

FIG. 8 is a flowchart illustrating an operation of the air conditioner according to the fourth embodiment of the present invention.

FIG. 9 is a sectional view of a conventional air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air conditioner 2 Compressor 3 Four-way valve 4 Outdoor heat exchanger 6 Indoor heat exchanger 8 Indoor capillary tube 10 Accumulator 11 Molecular sieves 12 Filter 13 Dryer 14, 15 Three-way valve 16 Calendar detection means 17, 20, 22, 24 Refrigerant circuit switching means 18 Outdoor capillary tube 19 Air conditioner operation time detecting means 21, 23 Refrigerant circuit control means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Takeya 4-5-2-5 Takaida Hondori, Higashi-Osaka City, Osaka Inside Matsushita Refrigerating Machinery Co., Ltd. (72) Inventor Hiroyuki Tanaka 4-chome, Takaida Hondo, Higashi-Osaka City, Osaka Prefecture No. 2 Matsushita Refrigerator Co., Ltd. (72) Inventor Masatoshi Takahashi 4-5-2 Takaida Hondori, Higashi-Osaka City, Osaka Prefecture No. 2 Matsushita Refrigerator Co., Ltd. Matsushita Refrigerating Machinery Co., Ltd. 4-5-2, Hondori (72) Inventor Akihiko Hyodo 4-5-2-5 Takaidahondori, Matsushita Refrigerating Machinery Co., Ltd., Higashi-Osaka, Osaka Matsushita Refrigeration Machinery Co., Ltd. (72) Inventor Masato Ariki 4-2-5 Takaida Hondori, Higashi Osaka City, Osaka Prefecture

Claims (4)

[Claims] 1. A cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate a refrigerant. Between the expansion valve and the capillary tube, a molecular sieve is provided in the center, and a bypass circuit is provided before and after or on one side of which is equipped with a filter that has a filter for trapping foreign substances such as dust and metal powder, and the daily time is measured. A switching means for switching to a bypass circuit for switching a refrigerant circuit to a bypass circuit side by a signal from the calendar detection means when the time reaches a predetermined time, and measuring an elapsed time since switching to the bypass circuit, When the time reaches a predetermined value, switching means for a refrigerant circuit to return to the original refrigerant circuit by a signal is provided. An air conditioner characterized by being radiated. 2. A cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate the refrigerant. Between the expansion valve and the capillary tube, there is provided a bypass circuit having a molecular sieve in the center and a dryer provided with a filter for capturing foreign matter such as dust and metal powder before and / or after the molecular sieve. Air conditioner operating time measuring means for measuring the operating time, and switching means to a bypass circuit for switching the refrigerant circuit to the bypass circuit side by a signal from the air conditioner operating time measuring means when the operating time reaches a predetermined value. Measure the elapsed time since switching to the bypass circuit, and return to the original refrigerant circuit when the time reaches a predetermined value Switching to the bypass circuit side by the air conditioner operating time integrating means for calculating the total value of the operating time detected by the switching means to the refrigerant circuit and the air conditioner operating time measuring means and the air conditioner operating time integrating means. An air conditioner comprising: a switching unit for switching to a bypass circuit, which determines whether or not the switching is performed and stops switching to the bypass circuit when the time reaches a predetermined value. 3. A cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate a refrigerant. Between the expansion valve and the capillary tube, a bypass circuit having a molecular sieve in the center and a dryer with a filter for capturing foreign matter such as dust and metal powder is provided before and / or after the molecular sieve. During the time T determined by the time t, the refrigerant is caused to flow through the bypass circuit for a predetermined time after the start of the operation of the air conditioner, and when the accumulated time t exceeds the predetermined time, switching to the bypass circuit is performed. Circuit switching that switches between the bypass circuit and the normal refrigerant circuit according to the signal of the refrigerant circuit control means and the refrigerant circuit control means that does not perform the operation. An air conditioner comprising means. 4. A cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve or a capillary tube, an indoor heat exchanger, an accumulator, and the like are sequentially connected by a refrigerant pipe to circulate a refrigerant. Between the expansion valve and the capillary tube, a bypass circuit having a molecular sieve in the center and a dryer with a filter for capturing foreign matter such as dust and metal powder is provided before and / or after the molecular sieve. During the time T determined by the time t, the refrigerant is caused to flow through the bypass circuit for a predetermined time after the start of the operation of the air conditioner, and when the accumulated time t exceeds the predetermined time, switching to the bypass circuit is performed. Switching between the bypass circuit and the normal refrigerant circuit by a signal of the refrigerant circuit control means for fixing the time to a predetermined value and the refrigerant circuit control means. An air conditioner having circuit switching means for performing the operation.