JP3798418B2 - air conditioner - Google Patents

Description

  The present invention relates to an air conditioner, and more particularly to an air conditioner that minimizes the flow of liquid refrigerant into a compressor during initial driving.

  In general, an air conditioner is an apparatus that realizes air conditioning by adjusting a state quantity such as a room temperature and humidity in a main building or office building using a refrigeration cycle. Here, the air conditioner is a device that realizes heating by heat dissipation by condensation in winter and cooling by heat absorption by evaporation in the summer by repeating compression, condensation, expansion, and evaporation of the refrigerant.

  Among the air conditioners, the GHP (Gas engine-driven heat pump) type air conditioner is an air conditioner that operates the compressor by the driving force of the gas engine and uses engine waste heat due to an increase in cooling demand in summer. It is widely used as an alternative to an EHP (Electric motor-drive Pump) type air conditioner that may cause an unstable power supply and demand problem.

  However, in such a conventional air conditioner, a liquid refrigerant (hereinafter referred to as “liquid refrigerant”) may flow into the compressor when the compressor is initially driven. For example, the compression of the liquid refrigerant flowing into the compressor before the evaporation of the liquid refrigerant in the pipe sucked into the compressor during the initial driving of the compressor, i.e., liquid compression occurs. Adversely affect.

  Thus, a method has been proposed in which the capacity of the accumulator is designed to be large in order to prevent the liquid refrigerant from flowing into the compressor to prevent the liquid refrigerant from flowing in, but the capacity of the accumulator is increased. As a result, the manufacturing cost is increased. In addition, in order to increase the amount of refrigerant that has flowed into the accumulator, hot gas bypass is used. In this case, there is a problem that the capacity of the system is reduced.

  Accordingly, an object of the present invention is to provide an air conditioner capable of minimizing the flow of liquid refrigerant into the compressor during initial driving while reducing the manufacturing cost.

  To achieve the above object, according to the present invention, an indoor heat exchange unit and an outdoor heat exchange unit, a compressor that forms a closed loop with the indoor heat exchange unit and the outdoor heat exchange unit, and compresses the refrigerant, and the compression An air conditioner having a compressor driving unit for driving the machine, a power opening and closing unit for opening and closing power transmission between the compressor driving unit and the compressor, and for cooling the compressor driving unit Cooling water circulates and forms a refrigerant heating circulation path for heating the refrigerant flowing into the compressor by the cooling water that has cooled the compressor driving unit, and the refrigerant heating circulation of the cooling water pipe A refrigerant heating unit that is provided on the path and heats the refrigerant flowing into the compressor with cooling water that has cooled the compressor driving unit, and cooling water that has cooled the compressor driving unit is the refrigerant heating Along the circulation path A cooling water valve for opening and closing the ring, and driving the compressor driving unit with the power opening and closing unit and the cooling water valve closed when the compressor driving unit is initially driven. It includes a control unit that opens the power opening / closing unit and the cooling water valve after elapse of time.

  The control unit further includes a temperature sensing unit that senses a temperature of cooling water that has cooled the compressor driving unit, and the control unit closes the power opening / closing unit and the cooling water valve when the compressor driving unit is initially driven. After the compressor driving unit is driven in the state of being operated, it is preferable to open the power opening / closing unit and the cooling water valve when the temperature sensed by the temperature sensing unit exceeds a predetermined reference temperature.

  In addition, the control unit senses the temperature sensing unit after driving the compressor driving unit with the power opening / closing unit and the cooling water valve closed when the compressor driving unit is initially driven. When the temperature exceeds the predetermined reference temperature, it is preferable that the power opening / closing part is opened after a predetermined time has elapsed after the cooling water valve is opened.

  And an expansion valve provided between the indoor heat exchange unit and the outdoor heat exchange unit to expand the refrigerant, and the control unit includes the power opening and closing unit and the power opening and closing unit when the compressor driving unit is initially driven. After the compressor driving unit is driven in a state where the cooling water valve is closed, the expansion valve is preferably opened when the temperature sensed by the temperature sensing unit exceeds the predetermined reference temperature.

  The cooling water pipe forms an outdoor heat exchange circulation path through which the cooling water that has cooled the compressor driving unit circulates to the outdoor heat exchanger, and the cooling water valve cools the compressor driving unit. The cooled cooling water can be selectively circulated along one of the refrigerant heating circulation path and the outdoor heat exchange circulation path.

  The control unit may be configured such that the cooling water that has cooled the compressor driving unit circulates along the outdoor heat exchange circulation path during cooling operation and circulates along the refrigerant heating circulation path during heating operation. It is preferable to control the cooling water valve.

  The control unit further includes a superheat degree detection unit that detects a superheat degree of the refrigerant flowing into the compressor, and the control unit closes the power opening / closing unit and the cooling water valve when the compressor drive unit is initially driven. After the compressor driving unit is driven in a heated state, the degree of superheat detected by the superheat degree detecting unit in a state where the temperature sensed by the temperature sensing unit exceeds a predetermined reference temperature is a predetermined reference overheating. When the temperature exceeds, the cooling water valve can be controlled corresponding to the cooling operation or the heating operation.

  The power transmission unit preferably includes a magnetic clutch.

  As described above, according to the present invention, it is possible to provide an air conditioner that can reduce manufacturing costs and minimize the inflow of liquid refrigerant into the compressor during initial driving.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

  As shown in FIG. 1, the air conditioner according to the present invention includes a compressor 6, an outdoor heat exchange unit 2, an expansion valve 7, and an indoor heat exchange unit 1 that are sequentially connected by a refrigerant pipe so as to form a closed loop. . The refrigerant pipe that connects the discharge side of the compressor 6 and the expansion valve 7 in the refrigerant pipe is a high-pressure pipe that guides the flow of the high-pressure refrigerant discharged from the compressor 6, and the expansion valve 7 and the compressor 6. The refrigerant pipe connecting the suction side is a low-pressure pipe for guiding the flow of the low-pressure refrigerant expanded by the expansion valve 7.

  The low pressure pipe and the high pressure pipe are crossed by a four-way valve 10. The four-way valve 10 selectively cools and heats the air conditioner according to the present invention by switching the flow of the refrigerant. Here, during the heating operation, as shown in FIG. 1, the refrigerant is in the direction of the dotted arrow, that is, the compressor 6, the four-way valve 10, the indoor heat exchange unit 1, the expansion valve 7, the outdoor heat exchange unit 2, the four-way valve 10, It will circulate along the compressor 6. As a result, the high pressure pipe during heating operation becomes a refrigerant pipe connecting the discharge side of the compressor 6, the four-way valve 10, the indoor heat exchange unit 1 and the expansion valve 7, and the low pressure pipe is the expansion valve 7 and the outdoor heat exchange. It becomes a refrigerant pipe which connects section 2, four-way valve 10, and the suction side of compressor 6. In the cooling operation, the direction of the solid arrow in FIG. 1, that is, along the compressor 6, the four-way valve 10, the outdoor heat exchange unit 2, the expansion valve 7, the indoor heat exchange unit 1, the four-way valve 10, and the compressor 6. Circulate. As a result, the high pressure pipe during the cooling operation becomes a refrigerant pipe connecting the discharge side of the compressor 6, the four-way valve 10, the outdoor heat exchange unit 2 and the expansion valve 7, and the low pressure pipe is the expansion valve 7 and the indoor heat exchange. It becomes a refrigerant pipe which connects section 1, four-way valve 10, and the suction side of compressor 6.

  An oil separator 8 is provided on the high-pressure pipe between the discharge side of the compressor 6 and the four-way valve 10. The oil separator 8 filters the oil contained in the refrigerant discharged from the compressor 6 and further moves it to the compressor 6. Here, the oil is used for lubrication when the compressor 6 is driven.

  The outdoor heat exchanging unit 2 is provided outside the outdoor heat exchanger 3 in which the refrigerant circulates, the cooling water radiator 4 in which the cooling water of the compressor driving unit 12 to be described later circulates, the outdoor heat exchanger 3 and the cooling A blower fan 5 for blowing air to the water radiator 4. The indoor heat exchanging unit 1 is provided in a room for cooling or heating, and performs a cooling or heating function by exchanging heat with indoor air when the refrigerant is circulated.

  An accumulator 9 is provided on the low pressure pipe on the suction side of the compressor 6. The accumulator 9 is provided to suppress the inflow of liquid refrigerant into the compressor 6.

  The expansion valve 7 can include an indoor expansion valve 7 a provided in the indoor heat exchange unit 1 and an outdoor expansion valve 7 b provided in the vicinity of the outdoor heat exchange unit 2. Here, the indoor expansion valve 7a expands the refrigerant flowing from the outdoor heat exchange unit 2 to the indoor heat exchange unit 1 during cooling, and the outdoor expansion valve 7b communicates with the outdoor heat exchange unit 2 from the indoor heat exchange unit 1 during heating. Expand the flowing refrigerant.

  Further, the air conditioner according to the present invention includes a compressor driving unit 12 that supplies driving force to the compressor 6. The GHP system using a gas engine driven by gas is applied to the air conditioner according to the present invention. Here, engine waste heat generated when the compressor drive unit 12 is driven is transmitted to the cooling water according to the circulation of the cooling water.

  The air conditioner according to the present invention includes a power opening / closing unit 13 that is controlled by the control unit 22 and opens and closes a power voltage between the compressor driving unit 12 and the compressor 6. In the present invention, the power opening / closing part 13 is compared with a magnetic clutch that connects the compressor driving part 12 and the compressor 6 in an axial manner.

  The air conditioner according to the present invention includes a cooling water circulation system for removing and / or utilizing engine waste heat generated when the compressor driving unit 12 is driven. The cooling water circulation system includes a cooling water pipe 23 that forms a closed loop, and a cooling water pump 19 that induces a flow of the cooling water. The cooling water formed along the cooling water pipe 23 by the cooling water pump 19 absorbs engine waste heat generated in the compressor driving unit 12 to cool the compressor driving unit 12, and the engine for cooling the compressor driving unit 12. The cooling water that has absorbed the waste heat is heated.

  Cooling water that has cooled the compressor driving unit 12, that is, cooling water heated by engine waste heat, returns to the compressor driving unit 12 through the thermostat 14 and flows to the cooling water valve 15. The thermostat 14 returns to the compressor driving unit 12 so that the cooling water cools the compressor driving unit 12 when the temperature of the heated cooling water is equal to or lower than a predetermined temperature, and the temperature of the heated cooling water is The cooling water flows to the cooling water valve 15 when the predetermined temperature is exceeded.

  The cooling water valve 15 is opened and closed so that the cooling water flowing from the thermostat 14 selectively flows to one of the refrigerant heating unit 11 and the outdoor heat exchange unit 2 under the control of the control unit 22. Hereinafter, the circulation path of the cooling water flowing to the outdoor heat exchange unit 2 side is referred to as an outdoor heat exchange circulation path, and the circulation path of the cooling water flowing to the refrigerant heating unit 11 side is referred to as a refrigerant heating circulation path.

  The control unit 22 controls the cooling water valve 15 so that the cooling water flowing from the thermostat 14 during the heating operation flows to the refrigerant heating unit 11 along the refrigerant heating circulation path, and the cooling flowing from the thermostat 14 during the cooling operation. The cooling water valve 15 is controlled so that water is supplied to the cooling water radiator 4 of the outdoor heat exchange unit 2 along the outdoor heat exchange circulation path.

  Further, the air conditioner according to the present invention includes a temperature sensing unit 20 that senses the temperature of the cooling water heated by the compressor driving unit 12, and a superheat degree detection unit 21 that detects the superheat degree of the refrigerant sucked into the compressor 6. Further included. Here, information on the temperature of the cooling water sensed by the temperature sensing unit 20 and information on the superheat degree of the refrigerant detected by the superheat degree detection unit 21 are transmitted to the control unit 22.

  In FIG. 1, reference numeral 16 is a cooling water tank in which cooling water is stored, reference numeral 17 is an exhaust gas heat exchanging section, and reference numeral 18 is an exhaust muffler.

  The flow of the refrigerant and the cooling water during the cooling operation and the heating operation of the air conditioner according to the present invention will be described as follows.

  First, during the cooling operation, the refrigerant sucked into the compressor 6 is compressed and discharged to the high-pressure pipe. Here, the oil contained in the high-temperature and high-pressure refrigerant discharged from the compressor 6 is filtered while passing through the oil separator 8 and further moves to the compressor 6. The refrigerant discharged from the compressor 6 moves to the outdoor heat exchange unit 2 through the four-way valve 10.

  Next, the refrigerant that has passed through the four-way valve 10 is condensed in the outdoor heat exchanger 2 and then moves to the indoor expansion valve 7a. In addition, the refrigerant expanded in a low temperature and low pressure state while passing through the indoor expansion valve 7a moves to the indoor heat exchanging unit 1 to exchange heat with the room, thereby performing a cooling function.

  Next, the refrigerant that has passed through the indoor heat exchanging unit 1 further flows into the compressor 6 through the four-way valve 10 and the accumulator 9.

  Here, the waste heat of the engine generated in the compressor driving unit 12 during the cooling operation is sucked into the cooling water and radiated to the outside through the cooling water radiator 4 of the outdoor heat exchange unit 2.

  Further, during the heating operation, the refrigerant discharged from the compressor 6 is condensed in the indoor heat exchange unit 1 through the oil separator and the four-way valve 10. Here, the heating function is performed by the heat dissipated during the condensation of the refrigerant in the indoor heat exchange unit 1.

  Next, the refrigerant condensed in the indoor heat exchange unit 1 is expanded by the outdoor expansion valve 7 b and flows into the outdoor heat exchanger 3. The refrigerant that has passed through the outdoor heat exchanger 3 passes through the four-way valve 10 and the refrigerant heating unit 11, but the control unit 22 uses the cooling water heated by the compressor driving unit 12 during the heating operation to enter the refrigerant heating circulation path. The refrigerant passing through the refrigerant heating unit 11 absorbs heat from the heated cooling water flowing through the refrigerant heating unit 11 to control the cooling water valve 15 so as to circulate along and flow toward the refrigerant heating unit 11. Thus, the refrigerant that has passed through the four-way valve 10 flows into the compressor 6 via the refrigerant heating unit 11 and the accumulator 9.

  In addition, a control process during initial driving of the air conditioner according to the present invention will be described with reference to FIG.

  First, when the cooling or heating function is selected, the control unit 22 drives the compressor driving unit 12 (S10). At this time, the control unit 22 controls the cooling water valve 15 so that the cooling water passing through the cooling water valve 15 circulates along the outdoor heat exchange circulation path and flows to the cooling water radiator 4 side, Keep it closed. Further, the power opening / closing unit 13 is closed so that the driving force from the compressor driving unit 12 is not transmitted to the compressor 6 (S11). Accordingly, the refrigerant is prevented from flowing into the compressor 6 during the initial driving, and the liquid refrigerant contained in the refrigerant flowing into the compressor 6 is temporarily blocked from flowing.

  At this time, the temperature sensing unit 20 senses the temperature of the cooling water heated by the compressor driving unit 12 and transmits it to the control unit 22. The control unit 22 detects the temperature of the cooling water sensed by the temperature sensing unit 20. Is inspected whether or not a predetermined reference temperature is exceeded (S12).

  Next, when the temperature of the cooling water sensed by the temperature sensing unit 20 exceeds the reference temperature, the control unit 22 causes the cooling water passing through the cooling water valve 15 to move toward the refrigerant heating unit 11 along the refrigerant heating circulation path. The cooling water valve 15 is controlled so as to flow to (S13). Thereby, the liquid refrigerant in the refrigerant can be removed by heating the refrigerant passing through the refrigerant heating unit 11 by the heated cooling water flowing toward the refrigerant heating unit 11.

  The control unit 22 also includes a power opening / closing unit 13 so that the driving force from the compressor driving unit 12 is transmitted to the compressor 6 when the temperature of the cooling water detected by the temperature detecting unit 20 exceeds the reference temperature. (S14), the compressor 6 is driven. Here, as shown in FIG. 4, the compressor 6 is preferably driven after a predetermined time has elapsed after the control of the cooling water valve 15 in order to minimize the inflow of liquid refrigerant. 4A is a diagram showing the drive time of the compressor drive unit 12, FIG. 4B is the compressor 6, FIG. 4C is a diagram showing the drive time of the cooling water valve 15, and the B region of FIG. 4C is the heated cooling water. Is a region facing the refrigerant heating unit 11 along the refrigerant heating circulation path, and region A represents a region where the heated cooling water is directed to the outdoor heat exchange unit 2 along the outdoor heat exchange circulation path. That is, FIG. 4C illustrates that the air conditioner is initially driven during the cooling operation. However, when the air conditioner performs the heating operation, the A region maintains the same state as the B region.

  Further, the control unit 22 opens the expansion valve 7 when the temperature of the cooling water detected by the temperature detection unit 20 exceeds the reference temperature (S15), so that the refrigerant flows into the compressor 6. To do.

  Next, the control unit 22 determines whether or not the superheat degree of the refrigerant detected by the superheat degree detection unit 21 exceeds a predetermined reference superheat degree (S16). Here, the control part 22 operates the cooling water valve 15 steadily, when the superheat degree detected by the superheat degree detection part 21 exceeds a reference | standard superheat degree (S17). That is, as described above, the control unit 22 controls the cooling water 15 according to the heating operation or the cooling operation.

  In the above-described embodiment, the control unit 22 controls the cooling water valve 15 and the power switching unit 13 based on the temperature sensed by the temperature sensing unit 20 at the initial startup of the compressor driving unit 12. After a predetermined time elapses during the initial driving, the cooling water valve 15 may be opened and the power opening / closing unit 13 may be opened.

  In this way, the power opening / closing unit 13 that opens and closes the power transmission between the compressor driving unit 12 and the compressor 6 and the cooling water for cooling the compressor driving unit 12 circulates to cool the compressor driving unit 12. The cooling water pipe 23 that forms the refrigerant heating circulation path for heating the refrigerant flowing into the compressor 6 by the cooled cooling water, and the refrigerant driving circulation path of the cooling water pipe 23 provided on the cooling water pipe 23 cools the compressor driving unit 12. The refrigerant heating unit 11 that heats the refrigerant flowing into the compressor 6 by the cooled cooling water, and the cooling water that opens and closes the cooling water that has cooled the compressor driving unit 12 circulates along the refrigerant heating circulation path After driving the compressor drive unit 12 in a state in which the power opening / closing unit 13 and the cooling water valve 15 are closed when the valve 15 and the compressor driving unit 12 are initially driven, the power opening / closing unit 13 and the cooling water are passed after a predetermined time has elapsed. Control unit 2 for opening the valve 15 By providing, it is possible to minimize the inflow of the liquid refrigerant to the compressor 6 at the time of initial drive.

  Further, it is not necessary to increase the capacity of the accumulator 9 in order to prevent the liquid refrigerant from flowing into the compressor 6 during the initial drive, and the manufacturing cost can be reduced.

It is a figure which shows the structure of the air conditioner by this invention. It is a control block diagram of the air conditioner by this invention. It is a control flowchart of the air conditioner by this invention. It is a figure which shows the drive time of the compressor drive part of an air conditioner by this invention, a compressor, and a cooling water valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Indoor heat exchange part 2 Outdoor heat exchange part 3 Outdoor heat exchange part 4 Cooling water radiator 5 Blower fan 6 Compressor 7 Expansion valve 8 Oil separator 9 Accumulator 10 Four-way valve 11 Refrigerant heating part 12 Compressor drive part 13 Power opening and closing Unit 14 Thermostat 15 Cooling water valve 16 Cooling water tank 17 Exhaust gas heat exchange unit 18 Exhaust muffler 19 Cooling water pump 20 Temperature sensing unit 21 Superheat detection unit 22 Control unit

Claims (8)

An indoor heat exchange unit and an outdoor heat exchange unit, a compressor that forms a closed loop with the indoor heat exchange unit and the outdoor heat exchange unit, and compresses the refrigerant; and a compressor drive unit for driving the compressor; In an air conditioner having
A power opening and closing unit for opening and closing power transmission between the compressor driving unit and the compressor;
Cooling water pipes that form a refrigerant heating circulation path for circulating cooling water for cooling the compressor driving unit and heating the refrigerant flowing into the compressor by the cooling water that has cooled the compressor driving unit When,
A refrigerant heating unit that is provided on the refrigerant heating circulation path of the cooling water pipe and that heats the refrigerant flowing into the compressor with cooling water that has cooled the compressor driving unit;
A cooling water valve that opens and closes that the cooling water that has cooled the compressor driving unit circulates along the refrigerant heating circulation path;
After the compressor driving unit is driven in a state where the power opening / closing unit and the cooling water valve are closed at the time of initial driving of the compressor driving unit, the power switching unit and the cooling water are passed after a predetermined time has elapsed An air conditioner comprising a control unit for opening a valve. A temperature sensing unit for sensing a temperature of cooling water that has cooled the compressor driving unit;
The controller drives the compressor drive unit with the power opening / closing unit and the cooling water valve closed when the compressor drive unit is initially driven, and then the temperature sensed by the temperature sensing unit is predetermined. 2. The air conditioner according to claim 1, wherein when the reference temperature is exceeded, the power opening and closing unit and the cooling water valve are opened.   The controller drives the compressor driving unit with the power opening / closing unit and the cooling water valve closed when the compressor driving unit is initially driven, and then detects the temperature detected by the temperature sensing unit. The air conditioner according to claim 2, wherein when the predetermined reference temperature is exceeded, the power opening / closing part is opened after a lapse of a predetermined time after the cooling water valve is opened. An expansion valve provided between the indoor heat exchange unit and the outdoor heat exchange unit to expand the refrigerant;
The controller drives the compressor driving unit with the power opening / closing unit and the cooling water valve closed when the compressor driving unit is initially driven, and then detects the temperature detected by the temperature sensing unit. The air conditioner according to claim 2, wherein the expansion valve is opened when the predetermined reference temperature is exceeded. The cooling water pipe forms an outdoor heat exchange circulation path through which the cooling water that has cooled the compressor driving unit circulates to the outdoor heat exchanger side,
The cooling water valve selectively circulates cooling water that has cooled the compressor driving unit along one of the refrigerant heating circulation path and the outdoor heat exchange circulation path. The air conditioner according to claim 4.   The controller is configured so that the cooling water that has cooled the compressor driving unit circulates along the outdoor heat exchange circulation path during cooling operation and circulates along the refrigerant heating circulation path during heating operation. The air conditioner according to claim 5, wherein the air valve is controlled. Further comprising a superheat degree detection unit for detecting the superheat degree of the refrigerant flowing into the compressor,
The control unit drives the compressor driving unit in a state where the power opening / closing unit and the cooling water valve are closed during initial driving of the compressor driving unit, and then the temperature sensed by the temperature sensing unit is detected. When the superheat degree detected by the superheat degree detection unit exceeds a predetermined reference superheat degree in a state where a predetermined reference temperature is exceeded, the cooling water valve is controlled corresponding to a cooling operation or a heating operation. The air conditioner according to claim 6. The air conditioner according to claim 1, wherein the power transmission unit includes a magnetic clutch.

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