US20100037642A1 - Compressor capacity control operation mechanism and air conditioner provided with same - Google Patents
Compressor capacity control operation mechanism and air conditioner provided with same Download PDFInfo
- Publication number
- US20100037642A1 US20100037642A1 US12/531,099 US53109908A US2010037642A1 US 20100037642 A1 US20100037642 A1 US 20100037642A1 US 53109908 A US53109908 A US 53109908A US 2010037642 A1 US2010037642 A1 US 2010037642A1
- Authority
- US
- United States
- Prior art keywords
- compressor
- pipe
- capillary tube
- valve
- flow channel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B13/00—Compression machines, plants or systems, with reversible cycle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
- F04C28/24—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valves
- F04C28/26—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valves using bypass channels
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/02—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
- F04C18/0207—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form
- F04C18/0215—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form where only one member is moving
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
- F25B41/24—Arrangement of shut-off valves for disconnecting a part of the refrigerant cycle, e.g. an outdoor part
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B49/00—Arrangement or mounting of control or safety devices
- F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
- F25B49/022—Compressor control arrangements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
- F25B2313/027—Compression machines, plants or systems with reversible cycle not otherwise provided for characterised by the reversing means
- F25B2313/02741—Compression machines, plants or systems with reversible cycle not otherwise provided for characterised by the reversing means using one four-way valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2500/00—Problems to be solved
- F25B2500/01—Geometry problems, e.g. for reducing size
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2600/00—Control issues
- F25B2600/02—Compressor control
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2600/00—Control issues
- F25B2600/02—Compressor control
- F25B2600/026—Compressor control by controlling unloaders
- F25B2600/0261—Compressor control by controlling unloaders external to the compressor
Definitions
- the present invention relates to a compressor capacity control operation mechanism and an air conditioner provided with the same; and particularly relates to a compressor capacity control operation mechanism connected to a compressor and capable of controlling the capacity of the compressor, and to an air conditioner provided with this mechanism.
- air conditioners including a vapor-compression refrigerant circuit.
- air conditioners including this type of refrigerant circuit there are those that use a configuration in which a compressor capacity control operation circuit is connected to a compressor, thereby making it possible to perform capacity control for switching the operating state of the compressor between a full load operation for bringing the discharge capacity to 100% with respect to the suction capacity, and an unload operation for reducing the discharge capacity relative to the suction capacity.
- the compressor capacity control operation circuit has a bypass pipe for connecting a cylinder intermediate part of the compressor and a suction pipe of the compressor, an electromagnetic valve provided to the bypass pipe and functioning as a two-way valve, a pilot pipe for connecting the discharge pipe of the compressor and the cylinder intermediate part of the compressor, and a capillary tube provided to the pilot pipe; wherein the compressor can be controlled into the full load operation by closing the electromagnetic valve, and the compressor can be controlled into the unload operation by opening the electromagnetic valve (for example, see Patent Document 1).
- an electromagnetic valve functioning as a two-way valve is provided not only to the bypass pipe but to the pilot pipe as well, and the electromagnetic valve provided to the bypass pipe is opened and the electromagnetic valve provided to the pilot pipe is closed during the unload operation, thereby making it possible to ensure that refrigerant does not flow from the discharge pipe into the bypass pipe through the pilot pipe.
- the compressor capacity control operation circuit requires two electromagnetic valves functioning as two-way valves, and the cost increases.
- An object of the present invention is to provide a compressor capacity control operation mechanism and an air conditioner provided with this mechanism, wherein cost increases can be prevented and the capacity of the compressor can be controlled in the same manner as in a case of using two two-way valves.
- a compressor capacity control operation mechanism is a compressor capacity control operation mechanism that is connected to a compressor and is capable of controlling the capacity of the compressor, comprising a flow channel switching valve, a suction branching pipe, an intermediate pipe, a discharge branching pipe, and a fixing member.
- the flow channel switching valve has a valve main body, a first capillary tube, a second capillary tube, and a third capillary tube.
- the valve main body has the same function as when two two-way valves are used to form a flow channel configuration capable of switching between a first state in which a first flow channel and a second flow channel are connected and a third flow channel is not connected to either the first or second flow channel, and a second state in which the second flow channel and the third flow channel are connected and the first flow channel is not connected to either the second or third flow channel.
- the first capillary tube constitutes the first flow channel and extends from the valve main body.
- the second capillary constitutes the second flow channel extends from the valve main body.
- a third capillary tube constitutes the third flow channel and extends from the valve main body.
- the suction branching pipe is a pipe that branches off from a suction pipe of the compressor, is connected to the first capillary tube, and has a larger diameter than the first capillary tube.
- the intermediate pipe is a pipe connected to a cylinder intermediate part of the compressor, connected to the second capillary tube, and provided with a larger diameter than the second capillary tube.
- the discharge branching pipe is a pipe that branches off from a discharge pipe of the compressor, is connected to the third capillary tube, and has a larger diameter than the third capillary tube.
- the fixing member fixes the flow channel switching valve and at least one of the suction branching pipe, the intermediate pipe, and the discharge branching pipe.
- the compressor capacity control operation mechanism is configured using a valve having the first, second, and third capillary tubes extending from the valve main body as the flow channel switching valve, strength is reduced in the portion of the first capillary tube connected to the suction branching pipe, the portion of the second capillary tube connected to the intermediate pipe, and the portion of the third capillary tube connected to the discharge branching pipe.
- the compressor capacity control operation mechanism In view of this, in the compressor capacity control operation mechanism, excessive stress is prevented from acting on the first, second, and third capillary tubes by fixing the flow channel switching valve and at least one of the suction branching pipe, the intermediate pipe, and the discharge branching pipe to the fixing member.
- a compressor capacity control operation mechanism can be provided, whereby the cost increase resulting from the use of two two-way valves is prevented and the same compressor capacity control is achieved as in the case of using two two-way valves.
- a compressor capacity control operation mechanism is the compressor capacity control operation mechanism according to the first aspect of the present invention, wherein among the suction branching pipe, the intermediate pipe, and the discharge branching pipe, one or those fixed to the fixing member are fixed to the fixing member at the portions in proximity to the corresponding capillary tubes.
- a compressor capacity control operation mechanism is a compressor capacity control operation mechanism connected to a compressor and capable of controlling the capacity of the compressor, the compressor capacity control operation mechanism comprising a pilot valve for use as a four-way switching valve having four connecting capillary tubes, a suction branching pipe, an intermediate pipe, and a discharge branching pipe.
- the suction branching pipe is connected to a first capillary tube as one of the four connecting capillary tubes and is branched off from a suction pipe of the compressor.
- the intermediate pipe is connected to a second capillary tube as one of the four connecting capillary tubes and is connected to a cylinder intermediate part of the compressor.
- the discharge branching pipe is connected to a third capillary tube as one of the four connecting capillary tubes and is branched off from a discharge pipe of the compressor.
- a compressor capacity control operation mechanism is the compressor capacity control operation mechanism according to the third aspect of the present invention, wherein a fourth capillary tube as one of the four connecting capillary tubes is closed off.
- the configuration is simplified because the same flow channel configuration as one configured from two two-way valves can be achieved by a simple process of closing off one of the four connecting capillary tubes of the pilot valve for use as a four-way switching valve.
- An air conditioner comprises a vapor-compression main refrigerant circuit including the compressor, a four-way switching valve, a first heat exchanger, an expansion mechanism, and a second heat exchanger; and the compressor capacity control operation mechanism according to the third or fourth aspect of the present invention; wherein the same valve as a pilot valve for use as a four-way switching valve constituting the four-way switching valve is used as the pilot valve for use as a four-way switching valve.
- the pilot valve for use as a four-way switching valve used in the compressor capacity control operation mechanism is the same pilot valve for use as a four-way switching valve constituting the four-way switching valve included in the main refrigerant circuit.
- FIG. 1 is a schematic configuration diagram of an air conditioner in which a compressor capacity control operation mechanism according to an embodiment of the present invention is used.
- FIG. 2 is a perspective view showing the schematic internal structure of an outdoor unit.
- FIG. 3 is a schematic longitudinal cross-sectional view showing the structure of part A in FIG. 1 (i.e., the structure of a compressor and a compressor capacity control operation circuit).
- FIG. 1 is a schematic configuration diagram of an air conditioner 1 in which a compressor capacity control operation mechanism according to an embodiment of the present invention is used.
- the air conditioner 1 is an apparatus used for cooling and heating a room interior, and is a so-called separated type air conditioner comprising primarily an outdoor unit 2 , an indoor unit 4 , and a first refrigerant communication pipe 6 and a second refrigerant communication pipe 7 connecting the outdoor unit 2 and the indoor unit 4 .
- the outdoor unit 2 and the indoor unit 4 are configured by being connected by the refrigerant communication pipes 6 , 7 constructed on site, after the outdoor and indoor units are shipped to the site of installation and installed.
- a refrigerant circuit 10 of the air conditioner 1 of the present embodiment is configured by connecting the outdoor unit 2 and the indoor unit 4 via the refrigerant communication pipes 6 , 7 .
- the indoor unit 4 is connected to the outdoor unit 2 via the first refrigerant communication pipe 6 and the second refrigerant communication pipe 7 , and the indoor unit 4 constitutes a part of the refrigerant circuit 10 .
- the indoor unit 4 primarily has an indoor refrigerant circuit 10 b constituting the part of the refrigerant circuit 10 .
- the indoor refrigerant circuit 10 b primarily has an indoor heat exchanger 41 as a second heat exchanger.
- the indoor heat exchanger 41 is a heat exchanger that functions as a refrigerant heater during cooling, and as a refrigerant cooler during heating.
- One end of the indoor heat exchanger 41 is connected to the second refrigerant communication pipe 7 , and the other end is connected to the first refrigerant communication pipe 6 .
- the indoor unit 4 comprises an indoor fan 42 for taking indoor air into the unit and supplying the air to the room interior after heat exchange has been conducted, and the indoor unit 4 is capable of conducting heat exchange between the indoor air and the refrigerant flowing through the indoor heat exchanger 41 .
- the indoor fan 42 is rotatably driven by an indoor fan motor 42 a.
- the indoor unit 4 also comprises an indoor controller 43 for controlling the operations of the components constituting the indoor unit 4 .
- the indoor controller 43 has a microcomputer, a memory and the like provided in order to control the indoor unit 4 , and is designed so as to be capable of exchanging control signals and the like with an outdoor controller 37 (described hereinafter) of the outdoor unit 2 .
- FIG. 2 is a perspective view showing the internal structure of the outdoor unit 2 .
- FIG. 3 is a schematic longitudinal cross-sectional view showing the structure of part A in FIG. 1 (i.e., the structure of a compressor 22 and a compressor capacity control operation circuit 35 ).
- the outdoor unit 2 is connected to the indoor unit 4 via the first refrigerant communication pipe 6 and the second refrigerant communication pipe 7 , and the outdoor unit 2 constitutes an outdoor refrigerant circuit 10 a as a part of the refrigerant circuit 10 .
- the outdoor unit 2 has a structure (a so-called trunk structure) in which the interior of a unit casing 51 shaped as substantially rectangular parallelepiped box is divided into an air blower chamber S 1 and a machinery chamber S 2 by a vertically extending partitioning plate 56 , and the outdoor unit 2 primarily has the unit casing 51 , outdoor refrigerant circuit structural components (described hereinafter) constituting the outdoor refrigerant circuit 10 a , an outdoor fan 36 , and an electrical component assembly (not shown in FIG. 2 ) which functions as an outdoor controller 37 (see FIG. 1 ) for controlling the operations of the components constituting the outdoor unit 2 .
- a structure a so-called trunk structure in which the interior of a unit casing 51 shaped as substantially rectangular parallelepiped box is divided into an air blower chamber S 1 and a machinery chamber S 2 by a vertically extending partitioning plate 56 , and the outdoor unit 2 primarily has the unit casing 51 , outdoor refrigerant circuit structural components (described hereinafter) constitu
- the unit casing 51 primarily has a bottom plate 52 , a top plate 53 (shown by chain double-dashed lines in FIG. 2 ), a front plate 54 (shown by chain double-dashed lines in FIG. 2 ), a side plate 55 (shown by chain double-dashed lines in FIG. 2 ), and a partitioning plate 56 .
- the bottom plate 52 is a horizontally-long substantially rectangular metal plate-shaped member constituting the bottom surface portion of the unit casing 51 .
- the peripheral edges of the bottom plate 52 are folded upward.
- the outer surface of the bottom plate 52 is provided with two fixing arms 57 fixed to the on-site installation surface.
- the fixing arms 57 are metal plate-shaped members having substantially U shapes in a front view of the unit casing 51 and extending from the front of the unit casing 51 toward the rear.
- the top plate 53 is a horizontally-long substantially rectangular metal plate-shaped member constituting the top surface portion of the outdoor unit 2 .
- the front plate 54 is primarily a metal plate-shaped member constituting the front surface portion and the front part of the right-side surface of the unit casing 51 , and the bottom part of the front plate 54 is fixed to the bottom plate 52 by screws or the like.
- a discharge port 54 a for blowing out air that has been taken into the air blower chamber S 1 through suction ports (not shown) formed in the back surface and left-side surface of the unit casing 51 .
- the side plate 55 is primarily a metal plate-shaped member constituting the rear part of the right-side surface and the right back surface portion of the unit casing 51 , and the bottom part of the side plate 55 is fixed to the bottom plate 52 by screws or the like.
- the partitioning plate 56 is a metal plate-shaped member disposed on the bottom plate 52 and extending vertically, and is disposed so as to partition the internal space in the unit casing 51 into two left and right spaces (i.e., the air blower chamber S 1 and the machinery chamber S 2 ).
- the bottom part of the partitioning plate 56 is fixed to the bottom plate 52 by screws or the like.
- the internal space of the unit casing 51 is divided into the air blower chamber S 1 and the machinery chamber S 2 by the partitioning plate 56 .
- the air blower chamber S 1 is a space enclosed by the bottom plate 52 , the top plate 53 , the front plate 54 , and the partitioning plate 56 ; and the machinery chamber S 2 is a space enclosed by the bottom plate 52 , the top plate 53 , the front plate 54 , the side plate 55 , and the partitioning plate 56 .
- An outdoor heat exchanger 24 and the outdoor fan 36 are disposed in the air blower chamber S 1 , and the compressor 22 , a four-way switching valve 23 , and other outdoor refrigerant circuit structural components, as well as the electrical component assembly (not shown) are disposed in the machinery chamber S 2 , as will be described hereinafter.
- the interior of the machinery chamber S 2 can be made visible by removing the portion of the front plate 54 that faces the machinery chamber S 2 .
- the outdoor refrigerant circuit structural components constituting the outdoor refrigerant circuit 10 a include primarily an accumulator 21 , the compressor 22 , the four-way switching valve 23 , the outdoor heat exchanger 24 as a first heat exchanger, an expansion valve 25 (not shown in FIG. 2 ) as an expansion mechanism, a first stop valve 26 , and a second stop valve 27 .
- the outdoor heat exchanger 24 is herein disposed in the air blower chamber S 1 , and the outdoor refrigerant circuit structural components other than the outdoor heat exchanger 24 are disposed in the machinery chamber S 2 .
- the accumulator 21 is a container for temporarily retaining a low-pressure refrigerant circulating within the refrigerant circuit 10 connected between the suction port of the compressor 22 and the four-way switching valve 23 , and is disposed in the right rear corner of the machinery chamber S 2 in the present embodiment (see FIG. 2 ).
- the outlet of the accumulator 21 is connected to the suction port of the compressor 22 by a first suction pipe 28 , and the inlet of the accumulator 21 is connected to the four-way switching valve 23 by a second suction pipe 29 .
- the compressor 22 is a compressor having the function of taking in and compressing low-pressure refrigerant and discharging the resulting high-pressure refrigerant, and is disposed in the substantial center of the machinery chamber S 2 in a plan view (see FIG. 2 ) in the present embodiment, in a state in which the space for accommodating the electrical component assembly (not shown in FIG. 2 ) and the four-way switching valve 23 and other outdoor refrigerant circuit structural components is opened on the upper side.
- the discharge port of the compressor 22 is connected to the four-way switching valve 23 by a discharge pipe 30 .
- the internal structure of the compressor 22 will be described hereinafter, as will be the compressor capacity control operation circuit 35 (not shown in FIG. 2 ) as a compressor capacity control operation mechanism connected to the compressor 22 .
- the compressor capacity control operation circuit 35 and the components other than the compressor capacity control operation circuit 35 in the refrigerant circuit 10 are described separately below.
- the components other than the compressor capacity control operation circuit 35 in the refrigerant circuit 10 are referred to as the main refrigerant circuit.
- the four-way switching valve 23 is a valve for switching the direction of refrigerant flow when switching between cooling and heating; and the valve is capable of connecting the discharge port of the compressor 22 with the outdoor heat exchanger 24 and the accumulator 21 with the second stop valve 27 during cooling, and of connecting the discharge port of the compressor 22 with the second stop valve 27 and the accumulator 21 with the outdoor heat exchanger 24 during heating.
- the four-way switching valve 23 is connected to the outdoor heat exchanger 24 by a first refrigerant pipe 31 (only partially shown in FIG. 2 ) and is connected to the second stop valve 27 by a fourth refrigerant pipe 34 .
- the four-way switching valve 23 has a four-way switching valve main component 23 a , and a pilot valve 23 b (not shown in FIG. 1 ) connected to the four-way switching valve main component 23 a .
- the pilot valve 23 b is referred to as a pilot valve for use as a four-way switching valve for operating the four-way switching valve main component 23 a when the aforementioned switch between cooling and heating is made, and the pilot valve 23 b is fixed to the four-way switching valve main component 23 a (see FIG. 2 ).
- the outdoor heat exchanger 24 is a heat exchanger that functions as a refrigerant cooler using outdoor air as a heat source during cooling, and as a refrigerant heater using outdoor air as a heat source during heating.
- One end of the outdoor heat exchanger 24 is connected to the first refrigerant pipe 31 (only partially shown in FIG. 2 ) via a plurality of branching pipes 24 a (not shown in FIG. 2 ).
- the other end of the outdoor heat exchanger 24 is connected to a second refrigerant pipe 32 via a plurality of branching pipes 24 b (not shown in FIG. 2 ) and a flow distributor 24 c (not shown in FIG. 2 ).
- the outdoor heat exchanger 24 is a cross-fin type fin-and-tube heat exchanger configured from a heat transfer tube and numerous fins, and is disposed in the air blower chamber S 1 .
- the outdoor heat exchanger 24 has an L shape in a plan view, and is disposed along the left side surface and back surface of the unit casing 51 .
- a tube plate 24 d is provided to the right end of the outdoor heat exchanger 24 .
- the expansion valve 25 (not shown in FIG. 2 ) is an electrical expansion valve capable of depressurizing the high-pressure refrigerant cooled in the outdoor heat exchanger 24 during cooling before the refrigerant is fed to the indoor heat exchanger 41 , and of depressurizing the high-pressure refrigerant cooled in the indoor heat exchanger 41 during heating before the refrigerant is fed to the outdoor heat exchanger 24 .
- One end of the expansion valve 25 is connected to the second refrigerant pipe 32 .
- the other end of the expansion valve 25 is connected to the first stop valve 26 by a third refrigerant pipe 33 .
- the first stop valve 26 is a valve provided to the connecting portion between the refrigerant pipe in the outdoor unit 2 (the third refrigerant pipe 33 in the present embodiment) the first refrigerant communication pipe 6 (shown by chain double-dashed lines in FIG. 2 ).
- the second stop valve 27 is a valve provided to the connecting portion between the refrigerant pipe in the outdoor unit 2 (the fourth refrigerant pipe 34 in the present embodiment) connects with the second refrigerant communication pipe 7 (shown by chain double-dashed lines in FIG. 2 ).
- the second stop valve 27 is connected to the four-way switching valve 23 by the fourth refrigerant pipe 34 .
- the outdoor fan 36 is an air-blowing fan that functions so as to take air into the air blower chamber S 1 through suction ports (not shown) formed in the left side surface and back surface of the unit casing 51 , and to blow the air from the discharge port 54 a formed in the front surface of the unit casing 51 after the air has passed through the outdoor heat exchanger 24 .
- the outdoor fan 36 is a propeller fan and is disposed downstream of the outdoor heat exchanger 24 in the air blower chamber S 1 .
- the outdoor fan 36 is configured so as to be rotatably driven by an outdoor fan motor 36 a.
- the electrical component assembly (not shown) is disposed in the upper space of the machinery chamber S 2 , and the assembly has a control board including a microcomputer or the like for performing operation control, an inverter board, and various other electrical components.
- the compressor 22 is a hermetic compressor in which primarily a compression element 62 , an Oldham ring 73 , a compressor motor 75 , and a bottom main bearing 76 are housed inside a casing 61 , which is an upright cylindrical container.
- the casing 61 primarily has a substantially cylindrical core plate 61 a , a top panel 61 b fixed by welding to the top end of the core plate 61 a , and a bottom panel 61 c fixed by welding to the bottom end of the core plate 61 a.
- the compression element 62 is a scroll-type compression element primarily having a housing 63 , a fixed scroll 64 disposed above the housing 63 , and an orbiting scroll 65 that meshes with the fixed scroll 64 .
- the housing 63 is fixed by press-fitting into the core plate 61 a in the external peripheral surface throughout the entire circumferential direction.
- the interior of the casing 61 is thereby partitioned into a high-pressure space S 3 at the lower part of the housing 63 and a low-pressure space S 4 at the upper part of the housing 63 .
- a housing concave part 63 a recessed in the center of the top surface and a bearing part 63 b extending downward from the center of the bottom surface are also formed in the housing 63 .
- a bearing hole 63 c penetrating through the bearing part 63 b in the vertical direction is formed therein, and a drive shaft 66 is rotatably fitted into the bearing hole 63 c via a bearing 67 .
- the fixed scroll 64 primarily has a panel 64 a , a spiral (involute) wrap 64 b formed on the bottom surface of the panel 64 a , and a second external peripheral wall 64 c enclosing the wrap 64 b .
- a discharge channel 69 communicated with a compression chamber 68 (described hereinafter) and an expanding concave part 70 communicated with the discharge channel 69 are formed in the panel 64 a .
- the discharge channel 69 is formed so as to extend vertically in the middle portion of the panel 64 a .
- the expanding concave part 70 is configured from a horizontally expanding concave part that is recessed in the top surface of the panel 64 a .
- a lid 71 is fixed by a bolt 72 to the top surface of the fixed scroll 64 so as to close off the expanding concave part 70 .
- the expanding concave part 70 is partitioned from the low-pressure space S 4 (i.e., communicated with the high-pressure space S 3 ), forming a muffler space S 5 composed of an expansion chamber for muffling operation noises in the compression element 62 .
- the orbiting scroll 65 primarily has a panel 65 a , a spiraling (involute) wrap 65 b formed on the top surface of the panel 65 a , a bearing part 65 c formed in the bottom surface of the panel 65 a , and a groove 65 d formed in both ends of the panel 65 a .
- the orbiting scroll 65 is supported on the housing 63 by fitting the Oldham ring 73 into the groove 65 d .
- the top end of the drive shaft 66 is also fitted into the bearing part 65 c .
- the orbiting scroll 65 is thus incorporated into the compression element 62 , whereby the orbiting scroll 65 revolves within the housing 63 without rotating on its axis due to the rotation of the drive shaft 66 .
- the wrap 65 b of the orbiting scroll 65 is meshed with the wrap 64 b of the fixed scroll 64 , and the compression chamber 68 is formed between the contact parts of the wraps 64 b , 65 b .
- the compression chamber 68 is designed so that the volume between the wraps 64 b , 65 b constricts toward the center along with the revolution of the orbiting scroll 65 .
- a communication channel 74 is formed through the fixed scroll 64 and the housing 63 in the compression element 62 .
- the communication channel 74 is formed so that a scroll-side channel 74 a formed in the fixed scroll 64 and a housing-side channel 74 b formed in the housing 63 are communicated with each other.
- the top end of the communication channel 74 i.e., the top end of the scroll-side channel 74 a , opens into the expanding concave part 70 ; and the bottom end of the communication channel 74 , i.e., the bottom end of the housing-side channel 74 b , opens into the high-pressure space S 3 from the bottom end surface of the housing 63 .
- the Oldham ring 73 is a member for preventing rotational movement of the orbiting scroll 65 as described above, and is fitted into an Oldham groove (not shown) formed in the housing 63 .
- the compressor motor 75 is a motor whose frequency can be controlled by an inverter control element or the like mounted on the electrical component assembly (not shown), and the motor is disposed below the compression element 62 .
- the compressor motor 75 primarily has an annular stator 75 a fixed to the internal wall surface of the casing 61 , and a rotor 75 b rotatably housed at a slight gap (air gap channel) from the internal peripheral side of the stator 75 a .
- a copper wire is wound around the stator 75 a , and coil ends are formed above and below.
- the rotor 75 b is linked to the orbiting scroll 65 of the compression element 62 by the vertically extending drive shaft 66 .
- the bottom main bearing 76 is disposed in a bottom space below the compressor motor 75 .
- the bottom main bearing 76 is fixed to the core plate 61 a , forms a bearing at the bottom end of the drive shaft 66 , and supports the drive shaft 66 .
- the top panel 61 b of the casing 61 is provided with a suction nozzle 77 running vertically through the low-pressure space S 4 and having an internal end fitted into the fixed scroll 64 to form the suction port of the compressor 22 .
- the core plate 61 a of the casing 61 is also provided with a discharge nozzle 78 whose inside end opens into the high-pressure space S 3 to form the discharge port of the compressor 22 .
- the compressor capacity control operation circuit 35 is connected to the compressor 22 of the present embodiment to allow capacity to be controlled so that the operating state is switched between a full load operation in which the discharge capacity is 100% with respect to the suction capacity, and an unload operation in which the discharge capacity is reduced with respect to the suction capacity.
- a cylinder intermediate part 79 is provided in order to implement this type of capacity control.
- the cylinder intermediate part 79 primarily has an unload channel 80 , a valve hole 81 , a bypass channel 82 , a valve 83 , a spring 84 , the above-described lid 71 , and an intermediate nozzle 85 .
- the unload channel 80 is formed in the fixed scroll 64 so as to extend vertically, and the bottom end of the unload channel is communicated with the compression chamber 68 .
- the valve hole 81 is formed in the fixed scroll 64 so as to extend upward from the top end of the unload channel 80 , and the top end of the valve hole 81 is covered by the lid 71 .
- the bypass channel 82 is a channel for guiding the refrigerant from the compression chamber 68 to the low-pressure space S 4 during the unload operation by establishing communication between the low-pressure space S 4 and the compression chamber 68 via the unload channel 80 and the valve hole 81 , thereby substantially delaying the start of compression.
- the bypass channel 82 is formed in the fixed scroll 64 so as to cause the valve holes 81 to communicate with the low-pressure space S 4 .
- the valve 83 is disposed in the valve hole 81 in a state of being urged upward by the spring 84 , and is designed to be capable of moving vertically within the valve hole 81 due to the balance between the urging force of the spring 84 and the pressure in an operational pressure chamber 86 formed above the valve 83 . Therefore, the unload channel 80 and the bypass channel 82 become divided by the valve 83 when the valve 83 has moved downward (i.e., the pressure in the operational pressure chamber 86 is greater than the urging force of the spring 84 ), and the unload channel 80 and the bypass channel 82 communicate with each other when the valve 83 has moved upward (i.e., the pressure in the operational pressure chamber 86 is less than the urging force of the spring 84 ).
- the intermediate nozzle 85 is provided so as to pass vertically through the top panel 61 b of the casing 61 , the low-pressure space S 4 , and the lid 71 ; and to be communicated with the operational pressure chamber 86 of the valve hole 81 .
- the valve 83 is operated according to the pressure applied to the operational pressure chamber 86 through the intermediate nozzle 85 , thereby forming a cylinder intermediate part 79 capable of opening and closing the unload channel 80 .
- the compressor capacity control operation circuit 35 is connected to the compressor 22 having this cylinder intermediate part 79 , as described above.
- the compressor capacity control operation circuit 35 primarily has a suction branching pipe 87 , an intermediate pipe 88 , a discharge branching pipe 89 , and a pilot valve 90 as a flow-channel switching valve, and is disposed in the space between the compressor 22 and the four-way switching valve 23 placed one above the other in the present embodiment (not shown in FIG. 2 ).
- the suction branching pipe 87 is a refrigerant pipe that branches off from the suction pipe 28 of the compressor 22 , and is smaller in diameter than the suction pipe 28 in the present embodiment.
- the intermediate pipe 88 is a refrigerant pipe connected to the cylinder intermediate part 79 of the compressor 22 (more specifically, the intermediate nozzle 85 ), and is substantially the same in diameter as the intermediate nozzle 85 in the present embodiment.
- the discharge branching pipe 89 is a refrigerant pipe that branches off from the discharge pipe 30 of the compressor 22 , and is smaller in diameter than the discharge pipe 30 in the present embodiment.
- the pilot valve 90 is a pilot valve for use as a four-way switching valve, primarily having a valve main body 91 , an electromagnetic coil 92 , and four connecting capillary tubes 93 a , 93 b , 93 c , 93 d .
- the valve main body 91 primarily has a valve case 94 , a valve body 95 , and a plunger 96 .
- the valve case 94 is a substantially cylindrical member having a hollow space in the interior, wherein four ports 94 a , 94 b , 94 c , 94 d communicated with the interior space are formed in the external periphery of the valve case 94 , and an opening 94 e through which the plunger 96 is reciprocatingly inserted is formed in a portion at one axial end.
- the second port 94 b , the first port 94 a , and the fourth port 94 d are disposed at substantially equal intervals in the axial direction from a position near the opening 94 e
- the third port 94 c is disposed so as to face the first port 94 a .
- the valve body 95 is disposed inside the valve case 94 and is linked to the axially distal end of the portion of the plunger 96 inserted into the valve case 94 .
- the valve body 95 has a bowl shape. Inserting the plunger 96 deep into the valve case 94 causes the valve body 95 to move away from the opening 94 e , allowing the first port 94 a and the fourth port 94 d to communicate with each other and also the second port 94 b and the third port 94 c to communicate with each other; and reducing the depth of the insertion of the plunger 96 in the valve case 94 causes the valve body 95 to move toward the opening 94 e , allowing the first port 94 a and the second port 94 b to communicate with each other and also the third port 94 c and the fourth port 94 d to communicate with each other.
- the electromagnetic coil 92 is disposed so as to enclose the external periphery of the portion of the plunger 96 protruding axially out of the valve case 94 .
- the plunger 96 in the nonconductive state, the plunger 96 is inserted deep into the valve case 94 , whereby the valve body 95 moves away from the opening 94 e , the first port 94 a and the fourth port 94 d are brought in communication with each other, and the second port 94 b and the third port 94 c are brought in communication with each other; and in the conductive state, the depth of the insertion of the plunger 96 into the valve case 94 is reduced, whereby the valve body 95 moves toward the opening 94 e , the first port 94 a and the second port 94 b are brought in communication with each other, and the third port 94 c and the fourth port 94 d are brought in communication with each other.
- One end of the first capillary tube 93 a is connected to the first port 94 a , and the other end is connected to the suction branching pipe 87 , which is larger in diameter than the first capillary tube 93 a .
- One end of the second capillary tube 93 b is connected to the second port 94 b , and the other end is connected to the intermediate pipe 88 , which is larger in diameter than the second capillary tube 93 b .
- One end of the third capillary tube 93 c is connected to the third port 94 c , and the other end is connected to the discharge branching pipe 89 , which is larger in diameter than the third capillary tube 93 c .
- One end of the fourth capillary tube 93 d is connected to the fourth port 94 d , and the other end is closed off.
- the valve main body 91 of the pilot valve 90 has the same function as when two two-way valves are used to form a flow channel configuration in which the suction branching pipe 87 and the first capillary tube 93 a communicated with the first port 94 a constitute a first flow channel, the intermediate pipe 88 and the second capillary tube 93 b communicated with the second port 94 b constitute a second flow channel, and the discharge branching pipe 89 and the third capillary tube 93 c communicated with the third port 94 c constitute a third flow channel; in which case it is possible to switch between a first state (corresponding to the conductive state of the electromagnetic coil 92 in the present embodiment) in which the first flow channel and the second flow channel are connected and the third flow channel is not connected to
- the state of the pilot valve 90 in FIG. 3 corresponds to a case in which the electromagnetic coil 92 is in the nonconductive state.
- the solid lines associated with the pilot valve 90 in FIG. 1 correspond to a case in which the electromagnetic coil 92 is in the nonconductive state, and the dashed lines associated with the pilot valve 90 in FIG. 1 correspond to a case in which the electromagnetic coil 92 is in the conductive state.
- the electromagnetic coil 92 When the full load operation is performed, the electromagnetic coil 92 is in the nonconductive state, whereby the second port 94 b and the third port 94 c of the pilot valve 90 are brought into communication with each other, and the first port 94 a is not communicated with either of the second or third ports 94 b , 94 c .
- the pressure of the cylinder intermediate part 79 in the operational pressure chamber 86 thereby increases, and the unload channel 80 and the bypass channel 82 are divided by the valve 83 , therefore allowing compression work to be performed without delaying the start of compression.
- the first port 94 a and the second port 94 b of the pilot valve 90 are brought into communication with each other, and the third port 94 c is not communicated with either of the first or second ports 94 a , 94 b .
- the pressure of the cylinder intermediate part 79 in the operational pressure chamber 86 thereby decreases, and the unload channel 80 and the bypass channel 82 are brought into communication with each other, the refrigerant is guided into the low-pressure space S 4 from the compression chamber 68 , and compression work is therefore performed with a delay in the start of compression.
- the compressor capacity control operation circuit 35 of the present embodiment uses the pilot valve 90 for the four-way switching valve instead of two two-way valves, the cost increase from using two two-way valves can be prevented, and the same capacity control for the compressor 22 can be achieved as in the case of using two two-way valves.
- the pilot valve 90 is given a flow channel configuration identical to a flow channel configuration composed of two two-way valves, this is achieved by a simple process of closing off one (the fourth capillary tube 93 d in the present embodiment) of the four connecting capillary tubes 93 a , 93 b , 93 c , 93 d , and the configuration is therefore simplified.
- valve used as the pilot valve 90 is the same as the pilot valve 23 b for use as a four-way switching valve constituting the four-way switching valve 23 included in the main refrigerant circuit, and components can therefore be shared, thereby contributing to reducing the cost of the entire air conditioner 1 .
- the pilot valve 90 for use as a four-way switching valve is used as a flow channel switching valve in the compressor capacity control operation circuit 35 of the present embodiment
- a valve is used in which the first, second, and third capillary tubes 93 a , 93 b , 93 c extend from the valve main body 91 . Therefore, strength is reduced in the portion of the first capillary tube 93 a connected with the suction branching pipe 87 , in the portion of the second capillary tube 93 b connected with the intermediate pipe 88 , and in the portion of the third capillary tube 93 c connected with the discharge branching pipe 89 .
- the pilot valve 90 and at least one of the suction branching pipe 87 , the intermediate pipe 88 , and the discharge branching pipe 89 are fixed to a fixing member 98 , thereby ensuring that excessive stress does not act on the first, second, and third capillary tubes 93 a , 93 b , 93 c , and enabling the use of the pilot valve 90 for use as a four-way switching valve.
- the fixing member 98 herein is a sheet-shaped member made of sheet metal, and is disposed in the present embodiment so as to at least face the connecting portion between the second capillary tube 93 b and the intermediate pipe 88 and the connecting portion between the third capillary tube 93 c and the discharge branching pipe 89 .
- the electromagnetic coil 92 is fixed to the fixing member 98 by a band member 97 e .
- the intermediate pipe 88 and the discharge branching pipe 89 are fixed to the fixing member 98 by band members 97 b , 97 c , respectively.
- the pipes fixed to the fixing member 98 among the suction branching pipe 87 , the intermediate pipe 88 , and the discharge branching pipe 89 are fixed to the fixing member 98 by the portions thereof in proximity to the corresponding capillary tubes 93 b , 93 c . Therefore, positional misalignment or the like in the capillary tube proximities of the suction branching pipe 87 , the intermediate pipe 88 , and the discharge branching pipe 89 can be reliably prevented, whereby stress acting on the first, second, and third capillary tubes 93 a , 93 b , 93 c can be reliably reduced.
- the connecting portion between the first capillary tube 93 a and the suction branching pipe 87 is not fixed to the fixing member 98 , but at least one of the suction branching pipe 87 , the intermediate pipe 88 , and the discharge branching pipe 89 is preferably fixed to the fixing member 98 .
- the suction branching pipe 87 may be fixed to the fixing member 98 by a band member similar to the intermediate pipe 88 and the discharge branching pipe 89 , or any one of the suction branching pipe 87 , the intermediate pipe 88 , and the discharge branching pipe 89 may be fixed to the fixing member 98 .
- the outdoor controller 37 has a microcomputer, a memory and the like provided in order to control the outdoor unit 2 , and the outdoor controller 37 is designed to be capable of exchanging control signals or the like with the indoor controller 43 of the indoor unit 4 .
- a controller as an operation control means for performing operation control for the air conditioner 1 is configured by the indoor controller 43 and the outdoor controller 37 .
- the outdoor refrigerant circuit 10 a , the indoor refrigerant circuit 10 b , and the refrigerant communication pipes 6 , 7 are connected as described above to form the refrigerant circuit 10 that is capable of heating and cooling a room interior and that has the main refrigerant circuit including the compressor 22 , the four-way switching valve 23 , the outdoor heat exchanger 24 as a first heat exchanger, the expansion valve 25 as an expansion mechanism, and the indoor heat exchanger 41 as a second heat exchanger, and also has the compressor capacity control operation circuit 35 connected to the compressor 22 and used to enable the capacity of the compressor 22 to be controlled.
- the air conditioner 1 of the present embodiment is designed to be capable of controlling the devices of the outdoor unit 2 and the indoor unit 4 by a controller configured from the indoor controller 43 and the outdoor controller 37 .
- the four-way switching valve 23 is in the state shown by the solid lines in FIG. 1 ; i.e., a state in which the discharge side of the compressor 22 is connected to the outdoor heat exchanger 24 and the suction side of the compressor 22 is connected to the second stop valve 27 .
- the degree of opening of the expansion valve 25 is adjustable.
- the stop valves 26 , 27 are in an open state.
- the electromagnetic coil 92 of the pilot valve 90 is in the nonconductive state.
- the low-pressure refrigerant is taken in by the compressor 22 and compressed to be a high-pressure refrigerant. Since the electromagnetic coil 92 of the pilot valve 90 is in the nonconductive state herein, the result is a state in which the second port 94 b and the third port 94 c of the pilot valve 90 are brought into communication with each other, and the first port 94 a is not communicated with either of the second or third ports 94 b , 94 c , whereby compression work is performed in the compressor 22 without delaying the start of compression, and a full load operation is performed in which the discharge capacity is 100% with respect to the suction capacity.
- the high-pressure refrigerant is then fed via the four-way switching valve 23 to the outdoor heat exchanger 24 functioning as a refrigerant cooler, heat exchange is conducted between the refrigerant and outdoor air supplied by the outdoor fan 36 , and the refrigerant is cooled.
- the high-pressure refrigerant cooled in the outdoor heat exchanger 24 is depressurized by the expansion valve 25 to be a low-pressure gas-liquid two-phase refrigerant, which is fed via the first stop valve 26 and the first refrigerant communication pipe 6 to the indoor unit 4 .
- the low-pressure gas-liquid two-phase refrigerant fed to the indoor unit 4 is heated through heat exchange with indoor air in the indoor heat exchanger 41 functioning as a refrigerant heater, and the refrigerant is thereby evaporated to be a low-pressure refrigerant.
- the low-pressure refrigerant heated in the indoor heat exchanger 41 is then fed via the second refrigerant communication pipe 7 to the outdoor unit 2 , and is again taken in by the compressor 22 via the second stop valve 27 , the four-way switching valve 23 , and the accumulator 21 .
- the capacity of the compressor 22 during the full load operation is controlled primarily by frequency control of the compressor motor 75 .
- the four-way switching valve 23 is in the state shown by the dashed lines in FIG. 1 ; i.e., a state in which the discharge side of the compressor 22 is connected to the second stop valve 27 , and the suction side of the compressor 22 is connected to the outdoor heat exchanger 24 .
- the degree of opening of the expansion valve 25 is adjustable.
- the stop valves 26 , 27 are in an open state.
- the electromagnetic coil 92 of the pilot valve 90 is in the nonconductive state.
- the low-pressure refrigerant is taken in by the compressor 22 and compressed to be a high-pressure refrigerant. Since the electromagnetic coil 92 of the pilot valve 90 is in the nonconductive state herein, the result is a state in which the second port 94 b and the third port 94 c of the pilot valve 90 are brought into communication with each other and the first port 94 a is not communicated with either of the second or third ports 94 b , 94 c , whereby compression work is performed in the compressor 22 without delaying the start of compression, and a full load operation is performed in which the discharge capacity is 100% with respect to the suction capacity.
- the high-pressure refrigerant is then fed via the four-way switching valve 23 , the second stop valve 27 , and the second refrigerant communication pipe 7 to the indoor unit 4 .
- the high-pressure refrigerant fed to the indoor unit 4 is then cooled through heat exchange with indoor air in the indoor heat exchanger 41 functioning as a refrigerant cooler, and the refrigerant is then fed via the first refrigerant communication pipe 6 to the outdoor unit 2 .
- the high-pressure refrigerant fed to the outdoor unit 2 is depressurized by the expansion valve 25 to be a low-pressure gas-liquid two-phase refrigerant, and then flows into the outdoor heat exchanger 24 functioning as a refrigerant heater.
- the low-pressure gas-liquid two-phase refrigerant that has flowed into the outdoor heat exchanger 24 is heated through heat exchange with outdoor air supplied by the outdoor fan 36 , the refrigerant is thereby evaporated to be a low-pressure refrigerant, and the refrigerant is taken back into the compressor 22 via the four-way switching valve 23 and the accumulator 21 . Thus, heating is performed.
- the capacity of the compressor 22 during the full load operation is controlled primarily by performing frequency control of the compressor motor 75 .
- the full load operation as described above is performed in areas in which the operating efficiency of the refrigeration cycle is comparatively favorable in cases in which the ratio of the pressure of the high-pressure refrigerant with respect to the pressure of the low-pressure refrigerant in the refrigeration cycle is suppressed at a predetermined range or lower, or in cases in which the frequency of the compressor motor 75 is in a comparatively high range. Therefore, there are many cases in which controlling the frequency of the compressor motor 75 is sufficient to control the capacity of the compressor 22 .
- the electromagnetic coil 92 of the pilot valve 90 is switched to the conductive state in such a case, creating a state in which the first port 94 a and the second port 94 b of the pilot valve 90 are brought into communication with each other, and the third port 94 c is not communicated with either of the first or second ports 94 a , 94 b , thereby creating a state in which the unload channel 80 and the bypass channel 82 are communicated with each other and the refrigerant is guided from the compression chamber 68 to the low-pressure space S 4 .
- Compression work is thereby performed in the compressor 22 in a state in which the start of compression is delayed, an unload operation is performed in which the discharge capacity is reduced with respect to the suction capacity, and an operation in the state in which the compressor motor 75 has a low frequency is avoided.
- the operating efficiency can thereby be prevented as much as possible from decreasing, even in cases in which the ratio of the pressure of the high-pressure refrigerant with respect to the pressure of the low-pressure refrigerant in the refrigeration cycle exceeds the predetermined range, or in cases in which the frequency of the compressor motor 75 is in a low range.
- the pilot valve 90 is designed so that there are no situations in which some of the refrigerant discharged from the compressor 22 is needlessly bypassed to the suction pipe 28 from the discharge pipe 30 , similar to a case of using two two-way valves, and increases in power consumption in the compressor 22 during the unload operation can therefore be suppressed.
- the number of electrical wires can be reduced and the control specifics can be simplified because it is only necessary to control just the pilot valve 90 .
- the fourth capillary tube 93 d was closed off among the four connecting capillary tubes 93 a to 93 d of the pilot valve 90 , but the present invention is not limited to this option, and any one of the four connecting capillary tubes 93 a to 93 d can be can be closed off.
- the capillary tubes connected to the suction branching pipe 87 , the intermediate pipe 88 , and the discharge branching pipe 89 are changed according to the closed off capillary tube, whereby the pilot valve 90 preferably has the same flow channel configuration as one configured from two two-way valves, similar to the embodiment described above.
- a scroll compressor was used as the compressor 22 , and the compressor motor 75 was disposed in the high-pressure space S 3 filled with high-pressure refrigerant, but the present invention is not limited to this option, and a rotary compressor or another such compressor may be used, and the compressor motor 75 may be disposed in a space filled with low-pressure refrigerant.
- the outdoor unit 2 had a design in which the interior of the unit casing 51 was divided by the partitioning plate 56 into the air blower chamber S 1 and the machinery chamber S 2 and the air taken into the unit casing 51 was blown out from the front surface of the unit casing 51 , but the present invention is not limited to this option, and another type of outdoor unit may be used, such as an outdoor unit having a design in which air taken into the unit casing is blown out from the top surface of the unit casing.
- the air conditioner 1 was a so-called paired and separated type air conditioner in which one indoor unit 4 was connected to one outdoor unit 2 , but other types of air conditioner may also be used, such as a remote-condenser type air conditioner or a multi-type air conditioner in which a plurality of indoor units are connected to one or more outdoor unit.
- Utilizing the present invention makes it possible to provide a compressor capacity control operation mechanism and an air conditioner comprising the mechanism wherein cost increases can be prevented and the capacity of the compressor can be controlled in the same manner as in a case of using two two-way valves.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Fluid Mechanics (AREA)
- Applications Or Details Of Rotary Compressors (AREA)
- Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
- Air Conditioning Control Device (AREA)
- Control Of Positive-Displacement Pumps (AREA)
Abstract
A compressor capacity control operation mechanism includes a pilot valve (flow channel switching valve) having capillary tubes, a suction branching pipe, an intermediate pipe, and a discharge branching pipe. The suction branching pipe is connected to a first capillary tube and branches off from a compressor suction pipe. The intermediate pipe is connected to a second capillary tube and a compressor cylinder intermediate part. The discharge branching pipe is connected to a third capillary tube and branches off from a compressor discharge pipe. Preferably, the suction, intermediate and discharge branching pipes have larger diameters than the first second and third capillary tubes. Also, the pilot valve preferably has a flow channel configuration switchable between first and second states in which the first, second and third capillary tubes are connected differently in the first and second states.
Description
- The present invention relates to a compressor capacity control operation mechanism and an air conditioner provided with the same; and particularly relates to a compressor capacity control operation mechanism connected to a compressor and capable of controlling the capacity of the compressor, and to an air conditioner provided with this mechanism.
- Conventionally, there have been air conditioners including a vapor-compression refrigerant circuit. Among air conditioners including this type of refrigerant circuit, there are those that use a configuration in which a compressor capacity control operation circuit is connected to a compressor, thereby making it possible to perform capacity control for switching the operating state of the compressor between a full load operation for bringing the discharge capacity to 100% with respect to the suction capacity, and an unload operation for reducing the discharge capacity relative to the suction capacity. The compressor capacity control operation circuit has a bypass pipe for connecting a cylinder intermediate part of the compressor and a suction pipe of the compressor, an electromagnetic valve provided to the bypass pipe and functioning as a two-way valve, a pilot pipe for connecting the discharge pipe of the compressor and the cylinder intermediate part of the compressor, and a capillary tube provided to the pilot pipe; wherein the compressor can be controlled into the full load operation by closing the electromagnetic valve, and the compressor can be controlled into the unload operation by opening the electromagnetic valve (for example, see Patent Document 1).
- <Patent Document 1>
- Japanese Laid-open Patent Application No. 9-72625
- However, in the compressor capacity control operation circuit described above, since merely the capillary tube is provided to the pilot pipe, the refrigerant flowing from the discharge pipe into the bypass pipe through the pilot pipe is added to the refrigerant flowing from the cylinder intermediate part into the suction pipe through the bypass pipe during the unload operation, and a situation occurs in which some of the refrigerant discharged from the compressor is needlessly bypassed to the suction pipe, which is a cause of an increase in power consumption in the compressor during the unload operation.
- To overcome this problem, an electromagnetic valve functioning as a two-way valve is provided not only to the bypass pipe but to the pilot pipe as well, and the electromagnetic valve provided to the bypass pipe is opened and the electromagnetic valve provided to the pilot pipe is closed during the unload operation, thereby making it possible to ensure that refrigerant does not flow from the discharge pipe into the bypass pipe through the pilot pipe. However, in this case, the compressor capacity control operation circuit requires two electromagnetic valves functioning as two-way valves, and the cost increases.
- An object of the present invention is to provide a compressor capacity control operation mechanism and an air conditioner provided with this mechanism, wherein cost increases can be prevented and the capacity of the compressor can be controlled in the same manner as in a case of using two two-way valves.
- A compressor capacity control operation mechanism according to a first aspect of the present invention is a compressor capacity control operation mechanism that is connected to a compressor and is capable of controlling the capacity of the compressor, comprising a flow channel switching valve, a suction branching pipe, an intermediate pipe, a discharge branching pipe, and a fixing member. The flow channel switching valve has a valve main body, a first capillary tube, a second capillary tube, and a third capillary tube. The valve main body has the same function as when two two-way valves are used to form a flow channel configuration capable of switching between a first state in which a first flow channel and a second flow channel are connected and a third flow channel is not connected to either the first or second flow channel, and a second state in which the second flow channel and the third flow channel are connected and the first flow channel is not connected to either the second or third flow channel. The first capillary tube constitutes the first flow channel and extends from the valve main body. The second capillary constitutes the second flow channel extends from the valve main body. A third capillary tube constitutes the third flow channel and extends from the valve main body. The suction branching pipe is a pipe that branches off from a suction pipe of the compressor, is connected to the first capillary tube, and has a larger diameter than the first capillary tube. The intermediate pipe is a pipe connected to a cylinder intermediate part of the compressor, connected to the second capillary tube, and provided with a larger diameter than the second capillary tube. The discharge branching pipe is a pipe that branches off from a discharge pipe of the compressor, is connected to the third capillary tube, and has a larger diameter than the third capillary tube. The fixing member fixes the flow channel switching valve and at least one of the suction branching pipe, the intermediate pipe, and the discharge branching pipe.
- Since the compressor capacity control operation mechanism is configured using a valve having the first, second, and third capillary tubes extending from the valve main body as the flow channel switching valve, strength is reduced in the portion of the first capillary tube connected to the suction branching pipe, the portion of the second capillary tube connected to the intermediate pipe, and the portion of the third capillary tube connected to the discharge branching pipe.
- In view of this, in the compressor capacity control operation mechanism, excessive stress is prevented from acting on the first, second, and third capillary tubes by fixing the flow channel switching valve and at least one of the suction branching pipe, the intermediate pipe, and the discharge branching pipe to the fixing member. Thus, a compressor capacity control operation mechanism can be provided, whereby the cost increase resulting from the use of two two-way valves is prevented and the same compressor capacity control is achieved as in the case of using two two-way valves.
- A compressor capacity control operation mechanism according to a second aspect of the present invention is the compressor capacity control operation mechanism according to the first aspect of the present invention, wherein among the suction branching pipe, the intermediate pipe, and the discharge branching pipe, one or those fixed to the fixing member are fixed to the fixing member at the portions in proximity to the corresponding capillary tubes.
- In this compressor capacity control operation mechanism, since one or those fixed to the fixing member among the suction branching pipe, the intermediate pipe, and the discharge branching pipe are fixed to the fixing member at the portions in proximity to the corresponding capillary tubes, it is possible to reliably prevent positional misalignment and the like in proximity to the capillary tubes of the suction branching pipe, the intermediate pipe, and the discharge branching pipe. The stress applied to the first, second, and third capillary tubes can thereby be reliably reduced.
- A compressor capacity control operation mechanism according to a third aspect of the present invention is a compressor capacity control operation mechanism connected to a compressor and capable of controlling the capacity of the compressor, the compressor capacity control operation mechanism comprising a pilot valve for use as a four-way switching valve having four connecting capillary tubes, a suction branching pipe, an intermediate pipe, and a discharge branching pipe. The suction branching pipe is connected to a first capillary tube as one of the four connecting capillary tubes and is branched off from a suction pipe of the compressor. The intermediate pipe is connected to a second capillary tube as one of the four connecting capillary tubes and is connected to a cylinder intermediate part of the compressor. The discharge branching pipe is connected to a third capillary tube as one of the four connecting capillary tubes and is branched off from a discharge pipe of the compressor.
- In this compressor capacity control operation mechanism, since the pilot valve for use as a four-way switching valve is used instead of two two-way valves, it is possible to provide a compressor capacity control operation mechanism whereby the cost increase resulting from the use of two two-way valves is prevented, and the same compressor capacity control is achieved as in the case of using two two-way valves.
- A compressor capacity control operation mechanism according to a fourth aspect of the present invention is the compressor capacity control operation mechanism according to the third aspect of the present invention, wherein a fourth capillary tube as one of the four connecting capillary tubes is closed off.
- In this compressor capacity control operation mechanism, the configuration is simplified because the same flow channel configuration as one configured from two two-way valves can be achieved by a simple process of closing off one of the four connecting capillary tubes of the pilot valve for use as a four-way switching valve.
- An air conditioner according to a fifth aspect of the present invention comprises a vapor-compression main refrigerant circuit including the compressor, a four-way switching valve, a first heat exchanger, an expansion mechanism, and a second heat exchanger; and the compressor capacity control operation mechanism according to the third or fourth aspect of the present invention; wherein the same valve as a pilot valve for use as a four-way switching valve constituting the four-way switching valve is used as the pilot valve for use as a four-way switching valve.
- In this air conditioner, components can be shared, thereby contributing to reducing the cost of the entire air conditioner, because the pilot valve for use as a four-way switching valve used in the compressor capacity control operation mechanism is the same pilot valve for use as a four-way switching valve constituting the four-way switching valve included in the main refrigerant circuit.
-
FIG. 1 is a schematic configuration diagram of an air conditioner in which a compressor capacity control operation mechanism according to an embodiment of the present invention is used. -
FIG. 2 is a perspective view showing the schematic internal structure of an outdoor unit. -
FIG. 3 is a schematic longitudinal cross-sectional view showing the structure of part A inFIG. 1 (i.e., the structure of a compressor and a compressor capacity control operation circuit). -
-
- 1 Air conditioner
- 22 Compressor
- 23 Four-way switching valve
- 24 Outdoor heat exchanger (first heat exchanger)
- 25 Expansion valve (expansion mechanism)
- 41 Indoor heat exchanger (second heat exchanger)
- 28 Suction pipe
- 30 Discharge pipe
- 79 Cylinder intermediate part
- 87 Suction branching pipe
- 88 Intermediate pipe
- 89 Discharge branching pipe
- 90, 23 b Pilot valve (flow channel switching valve, pilot valve for use as a four-way switching valve)
- 91, Valve main body
- 93 a First capillary tube
- 93 b Second capillary tube
- 93 c Third capillary tube
- 93 d Fourth capillary tube
- 98 Fixing member
- Embodiments of the compressor capacity control operation mechanism according to the present invention, and an air conditioner comprising this mechanism are described herein below with reference to the drawings.
-
FIG. 1 is a schematic configuration diagram of an air conditioner 1 in which a compressor capacity control operation mechanism according to an embodiment of the present invention is used. In the present embodiment, the air conditioner 1 is an apparatus used for cooling and heating a room interior, and is a so-called separated type air conditioner comprising primarily anoutdoor unit 2, an indoor unit 4, and a firstrefrigerant communication pipe 6 and a secondrefrigerant communication pipe 7 connecting theoutdoor unit 2 and the indoor unit 4. Specifically, in the present embodiment, theoutdoor unit 2 and the indoor unit 4 are configured by being connected by therefrigerant communication pipes refrigerant circuit 10 of the air conditioner 1 of the present embodiment is configured by connecting theoutdoor unit 2 and the indoor unit 4 via therefrigerant communication pipes - <Indoor Unit>
- Next, the configuration of the indoor unit 4 will be described using
FIG. 1 . - The indoor unit 4 is connected to the
outdoor unit 2 via the firstrefrigerant communication pipe 6 and the secondrefrigerant communication pipe 7, and the indoor unit 4 constitutes a part of therefrigerant circuit 10. The indoor unit 4 primarily has anindoor refrigerant circuit 10 b constituting the part of therefrigerant circuit 10. Theindoor refrigerant circuit 10 b primarily has anindoor heat exchanger 41 as a second heat exchanger. - In the present embodiment, the
indoor heat exchanger 41 is a heat exchanger that functions as a refrigerant heater during cooling, and as a refrigerant cooler during heating. One end of theindoor heat exchanger 41 is connected to the secondrefrigerant communication pipe 7, and the other end is connected to the firstrefrigerant communication pipe 6. - In the present embodiment, the indoor unit 4 comprises an
indoor fan 42 for taking indoor air into the unit and supplying the air to the room interior after heat exchange has been conducted, and the indoor unit 4 is capable of conducting heat exchange between the indoor air and the refrigerant flowing through theindoor heat exchanger 41. Theindoor fan 42 is rotatably driven by anindoor fan motor 42 a. - The indoor unit 4 also comprises an
indoor controller 43 for controlling the operations of the components constituting the indoor unit 4. Theindoor controller 43 has a microcomputer, a memory and the like provided in order to control the indoor unit 4, and is designed so as to be capable of exchanging control signals and the like with an outdoor controller 37 (described hereinafter) of theoutdoor unit 2. - <Outdoor Unit>
- Next, the configuration of the
outdoor unit 2 will be described usingFIGS. 1 through 3 .FIG. 2 is a perspective view showing the internal structure of theoutdoor unit 2.FIG. 3 is a schematic longitudinal cross-sectional view showing the structure of part A inFIG. 1 (i.e., the structure of acompressor 22 and a compressor capacity control operation circuit 35). - The
outdoor unit 2 is connected to the indoor unit 4 via the firstrefrigerant communication pipe 6 and the secondrefrigerant communication pipe 7, and theoutdoor unit 2 constitutes an outdoorrefrigerant circuit 10 a as a part of therefrigerant circuit 10. - The
outdoor unit 2 has a structure (a so-called trunk structure) in which the interior of aunit casing 51 shaped as substantially rectangular parallelepiped box is divided into an air blower chamber S1 and a machinery chamber S2 by a vertically extendingpartitioning plate 56, and theoutdoor unit 2 primarily has theunit casing 51, outdoor refrigerant circuit structural components (described hereinafter) constituting the outdoorrefrigerant circuit 10 a, anoutdoor fan 36, and an electrical component assembly (not shown inFIG. 2 ) which functions as an outdoor controller 37 (seeFIG. 1 ) for controlling the operations of the components constituting theoutdoor unit 2. - The
unit casing 51 primarily has abottom plate 52, a top plate 53 (shown by chain double-dashed lines inFIG. 2 ), a front plate 54 (shown by chain double-dashed lines inFIG. 2 ), a side plate 55 (shown by chain double-dashed lines inFIG. 2 ), and apartitioning plate 56. - The
bottom plate 52 is a horizontally-long substantially rectangular metal plate-shaped member constituting the bottom surface portion of theunit casing 51. The peripheral edges of thebottom plate 52 are folded upward. The outer surface of thebottom plate 52 is provided with two fixingarms 57 fixed to the on-site installation surface. The fixingarms 57 are metal plate-shaped members having substantially U shapes in a front view of theunit casing 51 and extending from the front of theunit casing 51 toward the rear. - The
top plate 53 is a horizontally-long substantially rectangular metal plate-shaped member constituting the top surface portion of theoutdoor unit 2. - The
front plate 54 is primarily a metal plate-shaped member constituting the front surface portion and the front part of the right-side surface of theunit casing 51, and the bottom part of thefront plate 54 is fixed to thebottom plate 52 by screws or the like. Formed in thefront plate 54 is a discharge port 54 a for blowing out air that has been taken into the air blower chamber S1 through suction ports (not shown) formed in the back surface and left-side surface of theunit casing 51. - The
side plate 55 is primarily a metal plate-shaped member constituting the rear part of the right-side surface and the right back surface portion of theunit casing 51, and the bottom part of theside plate 55 is fixed to thebottom plate 52 by screws or the like. - The
partitioning plate 56 is a metal plate-shaped member disposed on thebottom plate 52 and extending vertically, and is disposed so as to partition the internal space in theunit casing 51 into two left and right spaces (i.e., the air blower chamber S1 and the machinery chamber S2). The bottom part of thepartitioning plate 56 is fixed to thebottom plate 52 by screws or the like. - Thus, the internal space of the
unit casing 51 is divided into the air blower chamber S1 and the machinery chamber S2 by thepartitioning plate 56. More specifically, the air blower chamber S1 is a space enclosed by thebottom plate 52, thetop plate 53, thefront plate 54, and thepartitioning plate 56; and the machinery chamber S2 is a space enclosed by thebottom plate 52, thetop plate 53, thefront plate 54, theside plate 55, and thepartitioning plate 56. Anoutdoor heat exchanger 24 and theoutdoor fan 36 are disposed in the air blower chamber S1, and thecompressor 22, a four-way switching valve 23, and other outdoor refrigerant circuit structural components, as well as the electrical component assembly (not shown) are disposed in the machinery chamber S2, as will be described hereinafter. In theunit casing 51, the interior of the machinery chamber S2 can be made visible by removing the portion of thefront plate 54 that faces the machinery chamber S2. - The outdoor refrigerant circuit structural components constituting the outdoor
refrigerant circuit 10 a include primarily anaccumulator 21, thecompressor 22, the four-way switching valve 23, theoutdoor heat exchanger 24 as a first heat exchanger, an expansion valve 25 (not shown inFIG. 2 ) as an expansion mechanism, afirst stop valve 26, and asecond stop valve 27. Theoutdoor heat exchanger 24 is herein disposed in the air blower chamber S1, and the outdoor refrigerant circuit structural components other than theoutdoor heat exchanger 24 are disposed in the machinery chamber S2. - The
accumulator 21 is a container for temporarily retaining a low-pressure refrigerant circulating within therefrigerant circuit 10 connected between the suction port of thecompressor 22 and the four-way switching valve 23, and is disposed in the right rear corner of the machinery chamber S2 in the present embodiment (seeFIG. 2 ). The outlet of theaccumulator 21 is connected to the suction port of thecompressor 22 by afirst suction pipe 28, and the inlet of theaccumulator 21 is connected to the four-way switching valve 23 by asecond suction pipe 29. - The
compressor 22 is a compressor having the function of taking in and compressing low-pressure refrigerant and discharging the resulting high-pressure refrigerant, and is disposed in the substantial center of the machinery chamber S2 in a plan view (seeFIG. 2 ) in the present embodiment, in a state in which the space for accommodating the electrical component assembly (not shown inFIG. 2 ) and the four-way switching valve 23 and other outdoor refrigerant circuit structural components is opened on the upper side. The discharge port of thecompressor 22 is connected to the four-way switching valve 23 by adischarge pipe 30. The internal structure of thecompressor 22 will be described hereinafter, as will be the compressor capacity control operation circuit 35 (not shown inFIG. 2 ) as a compressor capacity control operation mechanism connected to thecompressor 22. The compressor capacitycontrol operation circuit 35 and the components other than the compressor capacitycontrol operation circuit 35 in therefrigerant circuit 10 are described separately below. In this description, the components other than the compressor capacitycontrol operation circuit 35 in therefrigerant circuit 10 are referred to as the main refrigerant circuit. - The four-
way switching valve 23 is a valve for switching the direction of refrigerant flow when switching between cooling and heating; and the valve is capable of connecting the discharge port of thecompressor 22 with theoutdoor heat exchanger 24 and theaccumulator 21 with thesecond stop valve 27 during cooling, and of connecting the discharge port of thecompressor 22 with thesecond stop valve 27 and theaccumulator 21 with theoutdoor heat exchanger 24 during heating. The four-way switching valve 23 is connected to theoutdoor heat exchanger 24 by a first refrigerant pipe 31 (only partially shown inFIG. 2 ) and is connected to thesecond stop valve 27 by a fourthrefrigerant pipe 34. In the present embodiment, the four-way switching valve 23 has a four-way switching valvemain component 23 a, and apilot valve 23 b (not shown inFIG. 1 ) connected to the four-way switching valvemain component 23 a. Thepilot valve 23 b is referred to as a pilot valve for use as a four-way switching valve for operating the four-way switching valvemain component 23 a when the aforementioned switch between cooling and heating is made, and thepilot valve 23 b is fixed to the four-way switching valvemain component 23 a (seeFIG. 2 ). - In the present embodiment, the
outdoor heat exchanger 24 is a heat exchanger that functions as a refrigerant cooler using outdoor air as a heat source during cooling, and as a refrigerant heater using outdoor air as a heat source during heating. One end of theoutdoor heat exchanger 24 is connected to the first refrigerant pipe 31 (only partially shown inFIG. 2 ) via a plurality of branchingpipes 24 a (not shown inFIG. 2 ). The other end of theoutdoor heat exchanger 24 is connected to a secondrefrigerant pipe 32 via a plurality of branchingpipes 24 b (not shown inFIG. 2 ) and aflow distributor 24 c (not shown inFIG. 2 ). In the present embodiment, theoutdoor heat exchanger 24 is a cross-fin type fin-and-tube heat exchanger configured from a heat transfer tube and numerous fins, and is disposed in the air blower chamber S1. Theoutdoor heat exchanger 24 has an L shape in a plan view, and is disposed along the left side surface and back surface of theunit casing 51. Atube plate 24 d is provided to the right end of theoutdoor heat exchanger 24. - In the present embodiment, the expansion valve 25 (not shown in
FIG. 2 ) is an electrical expansion valve capable of depressurizing the high-pressure refrigerant cooled in theoutdoor heat exchanger 24 during cooling before the refrigerant is fed to theindoor heat exchanger 41, and of depressurizing the high-pressure refrigerant cooled in theindoor heat exchanger 41 during heating before the refrigerant is fed to theoutdoor heat exchanger 24. One end of theexpansion valve 25 is connected to the secondrefrigerant pipe 32. The other end of theexpansion valve 25 is connected to thefirst stop valve 26 by a thirdrefrigerant pipe 33. - The
first stop valve 26 is a valve provided to the connecting portion between the refrigerant pipe in the outdoor unit 2 (the thirdrefrigerant pipe 33 in the present embodiment) the first refrigerant communication pipe 6 (shown by chain double-dashed lines inFIG. 2 ). Thesecond stop valve 27 is a valve provided to the connecting portion between the refrigerant pipe in the outdoor unit 2 (the fourthrefrigerant pipe 34 in the present embodiment) connects with the second refrigerant communication pipe 7 (shown by chain double-dashed lines inFIG. 2 ). Thesecond stop valve 27 is connected to the four-way switching valve 23 by the fourthrefrigerant pipe 34. - The
outdoor fan 36 is an air-blowing fan that functions so as to take air into the air blower chamber S1 through suction ports (not shown) formed in the left side surface and back surface of theunit casing 51, and to blow the air from the discharge port 54 a formed in the front surface of theunit casing 51 after the air has passed through theoutdoor heat exchanger 24. In the present embodiment, theoutdoor fan 36 is a propeller fan and is disposed downstream of theoutdoor heat exchanger 24 in the air blower chamber S1. Theoutdoor fan 36 is configured so as to be rotatably driven by anoutdoor fan motor 36 a. - The electrical component assembly (not shown) is disposed in the upper space of the machinery chamber S2, and the assembly has a control board including a microcomputer or the like for performing operation control, an inverter board, and various other electrical components.
- Next, the internal structure of the
compressor 22 and the compressor capacitycontrol operation circuit 35 will be described in detail. - In the present embodiment, the
compressor 22 is a hermetic compressor in which primarily acompression element 62, anOldham ring 73, acompressor motor 75, and a bottommain bearing 76 are housed inside acasing 61, which is an upright cylindrical container. - The
casing 61 primarily has a substantiallycylindrical core plate 61 a, atop panel 61 b fixed by welding to the top end of thecore plate 61 a, and abottom panel 61 c fixed by welding to the bottom end of thecore plate 61 a. - The
compression element 62 is a scroll-type compression element primarily having ahousing 63, a fixedscroll 64 disposed above thehousing 63, and anorbiting scroll 65 that meshes with the fixedscroll 64. Thehousing 63 is fixed by press-fitting into thecore plate 61 a in the external peripheral surface throughout the entire circumferential direction. The interior of thecasing 61 is thereby partitioned into a high-pressure space S3 at the lower part of thehousing 63 and a low-pressure space S4 at the upper part of thehousing 63. A housingconcave part 63 a recessed in the center of the top surface and a bearingpart 63 b extending downward from the center of the bottom surface are also formed in thehousing 63. A bearinghole 63 c penetrating through the bearingpart 63 b in the vertical direction is formed therein, and adrive shaft 66 is rotatably fitted into the bearinghole 63 c via abearing 67. The fixedscroll 64 primarily has apanel 64 a, a spiral (involute) wrap 64 b formed on the bottom surface of thepanel 64 a, and a second externalperipheral wall 64 c enclosing thewrap 64 b. Adischarge channel 69 communicated with a compression chamber 68 (described hereinafter) and an expandingconcave part 70 communicated with thedischarge channel 69 are formed in thepanel 64 a. Thedischarge channel 69 is formed so as to extend vertically in the middle portion of thepanel 64 a. The expandingconcave part 70 is configured from a horizontally expanding concave part that is recessed in the top surface of thepanel 64 a. Alid 71 is fixed by abolt 72 to the top surface of the fixedscroll 64 so as to close off the expandingconcave part 70. By covering up the expandingconcave part 70 with thelid 71, the expandingconcave part 70 is partitioned from the low-pressure space S4 (i.e., communicated with the high-pressure space S3), forming a muffler space S5 composed of an expansion chamber for muffling operation noises in thecompression element 62. The orbitingscroll 65 primarily has apanel 65 a, a spiraling (involute) wrap 65 b formed on the top surface of thepanel 65 a, a bearingpart 65 c formed in the bottom surface of thepanel 65 a, and agroove 65 d formed in both ends of thepanel 65 a. The orbitingscroll 65 is supported on thehousing 63 by fitting theOldham ring 73 into thegroove 65 d. The top end of thedrive shaft 66 is also fitted into the bearingpart 65 c. The orbitingscroll 65 is thus incorporated into thecompression element 62, whereby the orbitingscroll 65 revolves within thehousing 63 without rotating on its axis due to the rotation of thedrive shaft 66. Thewrap 65 b of the orbitingscroll 65 is meshed with thewrap 64 b of the fixedscroll 64, and thecompression chamber 68 is formed between the contact parts of thewraps compression chamber 68 is designed so that the volume between thewraps scroll 65. Acommunication channel 74 is formed through the fixedscroll 64 and thehousing 63 in thecompression element 62. Thecommunication channel 74 is formed so that a scroll-side channel 74 a formed in the fixedscroll 64 and a housing-side channel 74 b formed in thehousing 63 are communicated with each other. The top end of thecommunication channel 74, i.e., the top end of the scroll-side channel 74 a, opens into the expandingconcave part 70; and the bottom end of thecommunication channel 74, i.e., the bottom end of the housing-side channel 74 b, opens into the high-pressure space S3 from the bottom end surface of thehousing 63. - The
Oldham ring 73 is a member for preventing rotational movement of the orbitingscroll 65 as described above, and is fitted into an Oldham groove (not shown) formed in thehousing 63. - In the present embodiment, the
compressor motor 75 is a motor whose frequency can be controlled by an inverter control element or the like mounted on the electrical component assembly (not shown), and the motor is disposed below thecompression element 62. Thecompressor motor 75 primarily has anannular stator 75 a fixed to the internal wall surface of thecasing 61, and arotor 75 b rotatably housed at a slight gap (air gap channel) from the internal peripheral side of thestator 75 a. A copper wire is wound around thestator 75 a, and coil ends are formed above and below. Therotor 75 b is linked to theorbiting scroll 65 of thecompression element 62 by the vertically extendingdrive shaft 66. - The bottom
main bearing 76 is disposed in a bottom space below thecompressor motor 75. The bottommain bearing 76 is fixed to thecore plate 61 a, forms a bearing at the bottom end of thedrive shaft 66, and supports thedrive shaft 66. - The
top panel 61 b of thecasing 61 is provided with asuction nozzle 77 running vertically through the low-pressure space S4 and having an internal end fitted into the fixedscroll 64 to form the suction port of thecompressor 22. Thecore plate 61 a of thecasing 61 is also provided with adischarge nozzle 78 whose inside end opens into the high-pressure space S3 to form the discharge port of thecompressor 22. - Furthermore, the compressor capacity
control operation circuit 35 is connected to thecompressor 22 of the present embodiment to allow capacity to be controlled so that the operating state is switched between a full load operation in which the discharge capacity is 100% with respect to the suction capacity, and an unload operation in which the discharge capacity is reduced with respect to the suction capacity. A cylinderintermediate part 79 is provided in order to implement this type of capacity control. The cylinderintermediate part 79 primarily has an unloadchannel 80, avalve hole 81, abypass channel 82, avalve 83, a spring 84, the above-describedlid 71, and anintermediate nozzle 85. - The unload
channel 80 is formed in the fixedscroll 64 so as to extend vertically, and the bottom end of the unload channel is communicated with thecompression chamber 68. - The
valve hole 81 is formed in the fixedscroll 64 so as to extend upward from the top end of the unloadchannel 80, and the top end of thevalve hole 81 is covered by thelid 71. - The
bypass channel 82 is a channel for guiding the refrigerant from thecompression chamber 68 to the low-pressure space S4 during the unload operation by establishing communication between the low-pressure space S4 and thecompression chamber 68 via the unloadchannel 80 and thevalve hole 81, thereby substantially delaying the start of compression. Thebypass channel 82 is formed in the fixedscroll 64 so as to cause the valve holes 81 to communicate with the low-pressure space S4. - The
valve 83 is disposed in thevalve hole 81 in a state of being urged upward by the spring 84, and is designed to be capable of moving vertically within thevalve hole 81 due to the balance between the urging force of the spring 84 and the pressure in an operational pressure chamber 86 formed above thevalve 83. Therefore, the unloadchannel 80 and thebypass channel 82 become divided by thevalve 83 when thevalve 83 has moved downward (i.e., the pressure in the operational pressure chamber 86 is greater than the urging force of the spring 84), and the unloadchannel 80 and thebypass channel 82 communicate with each other when thevalve 83 has moved upward (i.e., the pressure in the operational pressure chamber 86 is less than the urging force of the spring 84). - The
intermediate nozzle 85 is provided so as to pass vertically through thetop panel 61 b of thecasing 61, the low-pressure space S4, and thelid 71; and to be communicated with the operational pressure chamber 86 of thevalve hole 81. Thus, in thecompressor 2, thevalve 83 is operated according to the pressure applied to the operational pressure chamber 86 through theintermediate nozzle 85, thereby forming a cylinderintermediate part 79 capable of opening and closing the unloadchannel 80. - The compressor capacity
control operation circuit 35 is connected to thecompressor 22 having this cylinderintermediate part 79, as described above. The compressor capacitycontrol operation circuit 35 primarily has asuction branching pipe 87, anintermediate pipe 88, adischarge branching pipe 89, and apilot valve 90 as a flow-channel switching valve, and is disposed in the space between thecompressor 22 and the four-way switching valve 23 placed one above the other in the present embodiment (not shown inFIG. 2 ). - The
suction branching pipe 87 is a refrigerant pipe that branches off from thesuction pipe 28 of thecompressor 22, and is smaller in diameter than thesuction pipe 28 in the present embodiment. - The
intermediate pipe 88 is a refrigerant pipe connected to the cylinderintermediate part 79 of the compressor 22 (more specifically, the intermediate nozzle 85), and is substantially the same in diameter as theintermediate nozzle 85 in the present embodiment. - The
discharge branching pipe 89 is a refrigerant pipe that branches off from thedischarge pipe 30 of thecompressor 22, and is smaller in diameter than thedischarge pipe 30 in the present embodiment. - In the present embodiment, the
pilot valve 90 is a pilot valve for use as a four-way switching valve, primarily having a valvemain body 91, anelectromagnetic coil 92, and four connectingcapillary tubes main body 91 primarily has avalve case 94, avalve body 95, and aplunger 96. Thevalve case 94 is a substantially cylindrical member having a hollow space in the interior, wherein fourports valve case 94, and anopening 94 e through which theplunger 96 is reciprocatingly inserted is formed in a portion at one axial end. In the present embodiment, thesecond port 94 b, thefirst port 94 a, and thefourth port 94 d are disposed at substantially equal intervals in the axial direction from a position near theopening 94 e, and thethird port 94 c is disposed so as to face thefirst port 94 a. Thevalve body 95 is disposed inside thevalve case 94 and is linked to the axially distal end of the portion of theplunger 96 inserted into thevalve case 94. In the present embodiment, thevalve body 95 has a bowl shape. Inserting theplunger 96 deep into thevalve case 94 causes thevalve body 95 to move away from theopening 94 e, allowing thefirst port 94 a and thefourth port 94 d to communicate with each other and also thesecond port 94 b and thethird port 94 c to communicate with each other; and reducing the depth of the insertion of theplunger 96 in thevalve case 94 causes thevalve body 95 to move toward theopening 94 e, allowing thefirst port 94 a and thesecond port 94 b to communicate with each other and also thethird port 94 c and thefourth port 94 d to communicate with each other. Theelectromagnetic coil 92 is disposed so as to enclose the external periphery of the portion of theplunger 96 protruding axially out of thevalve case 94. In the present embodiment, in the nonconductive state, theplunger 96 is inserted deep into thevalve case 94, whereby thevalve body 95 moves away from theopening 94 e, thefirst port 94 a and thefourth port 94 d are brought in communication with each other, and thesecond port 94 b and thethird port 94 c are brought in communication with each other; and in the conductive state, the depth of the insertion of theplunger 96 into thevalve case 94 is reduced, whereby thevalve body 95 moves toward theopening 94 e, thefirst port 94 a and thesecond port 94 b are brought in communication with each other, and thethird port 94 c and thefourth port 94 d are brought in communication with each other. One end of the firstcapillary tube 93 a is connected to thefirst port 94 a, and the other end is connected to thesuction branching pipe 87, which is larger in diameter than the firstcapillary tube 93 a. One end of the secondcapillary tube 93 b is connected to thesecond port 94 b, and the other end is connected to theintermediate pipe 88, which is larger in diameter than the secondcapillary tube 93 b. One end of the thirdcapillary tube 93 c is connected to thethird port 94 c, and the other end is connected to thedischarge branching pipe 89, which is larger in diameter than the thirdcapillary tube 93 c. One end of the fourthcapillary tube 93 d is connected to thefourth port 94 d, and the other end is closed off. Thus, one of the four connecting capillary tubes, the fourthcapillary tube 93 d, is closed off, whereby the valvemain body 91 of thepilot valve 90 has the same function as when two two-way valves are used to form a flow channel configuration in which thesuction branching pipe 87 and the firstcapillary tube 93 a communicated with thefirst port 94 a constitute a first flow channel, theintermediate pipe 88 and the secondcapillary tube 93 b communicated with thesecond port 94 b constitute a second flow channel, and thedischarge branching pipe 89 and the thirdcapillary tube 93 c communicated with thethird port 94 c constitute a third flow channel; in which case it is possible to switch between a first state (corresponding to the conductive state of theelectromagnetic coil 92 in the present embodiment) in which the first flow channel and the second flow channel are connected and the third flow channel is not connected to either the first or second flow channel, and a second state (corresponding to the nonconductive state of theelectromagnetic coil 92 in the present embodiment) in which the second flow channel and the third flow channel are connected and the first flow channel is not connected to either the second or third flow channel. The state of thepilot valve 90 inFIG. 3 corresponds to a case in which theelectromagnetic coil 92 is in the nonconductive state. The solid lines associated with thepilot valve 90 inFIG. 1 correspond to a case in which theelectromagnetic coil 92 is in the nonconductive state, and the dashed lines associated with thepilot valve 90 inFIG. 1 correspond to a case in which theelectromagnetic coil 92 is in the conductive state. - When the full load operation is performed, the
electromagnetic coil 92 is in the nonconductive state, whereby thesecond port 94 b and thethird port 94 c of thepilot valve 90 are brought into communication with each other, and thefirst port 94 a is not communicated with either of the second orthird ports intermediate part 79 in the operational pressure chamber 86 thereby increases, and the unloadchannel 80 and thebypass channel 82 are divided by thevalve 83, therefore allowing compression work to be performed without delaying the start of compression. When the unload operation is performed, thefirst port 94 a and thesecond port 94 b of thepilot valve 90 are brought into communication with each other, and thethird port 94 c is not communicated with either of the first orsecond ports intermediate part 79 in the operational pressure chamber 86 thereby decreases, and the unloadchannel 80 and thebypass channel 82 are brought into communication with each other, the refrigerant is guided into the low-pressure space S4 from thecompression chamber 68, and compression work is therefore performed with a delay in the start of compression. - Thus, since the compressor capacity
control operation circuit 35 of the present embodiment uses thepilot valve 90 for the four-way switching valve instead of two two-way valves, the cost increase from using two two-way valves can be prevented, and the same capacity control for thecompressor 22 can be achieved as in the case of using two two-way valves. Moreover, when thepilot valve 90 is given a flow channel configuration identical to a flow channel configuration composed of two two-way valves, this is achieved by a simple process of closing off one (the fourthcapillary tube 93 d in the present embodiment) of the four connectingcapillary tubes pilot valve 90 is the same as thepilot valve 23 b for use as a four-way switching valve constituting the four-way switching valve 23 included in the main refrigerant circuit, and components can therefore be shared, thereby contributing to reducing the cost of the entire air conditioner 1. - However, since the
pilot valve 90 for use as a four-way switching valve is used as a flow channel switching valve in the compressor capacitycontrol operation circuit 35 of the present embodiment, a valve is used in which the first, second, and thirdcapillary tubes main body 91. Therefore, strength is reduced in the portion of the firstcapillary tube 93 a connected with thesuction branching pipe 87, in the portion of the secondcapillary tube 93 b connected with theintermediate pipe 88, and in the portion of the thirdcapillary tube 93 c connected with thedischarge branching pipe 89. - In view of this, in the compressor capacity
control operation circuit 35 of the present embodiment, thepilot valve 90 and at least one of thesuction branching pipe 87, theintermediate pipe 88, and the discharge branching pipe 89 (theintermediate pipe 88 and thedischarge branching pipe 89 herein) are fixed to a fixingmember 98, thereby ensuring that excessive stress does not act on the first, second, and thirdcapillary tubes pilot valve 90 for use as a four-way switching valve. The fixingmember 98 herein is a sheet-shaped member made of sheet metal, and is disposed in the present embodiment so as to at least face the connecting portion between the secondcapillary tube 93 b and theintermediate pipe 88 and the connecting portion between the thirdcapillary tube 93 c and thedischarge branching pipe 89. In thepilot valve 90, theelectromagnetic coil 92 is fixed to the fixingmember 98 by aband member 97 e. Theintermediate pipe 88 and thedischarge branching pipe 89 are fixed to the fixingmember 98 byband members member 98 among thesuction branching pipe 87, theintermediate pipe 88, and the discharge branching pipe 89 (theintermediate pipe 88 and thedischarge branching pipe 89 herein) are fixed to the fixingmember 98 by the portions thereof in proximity to the correspondingcapillary tubes suction branching pipe 87, theintermediate pipe 88, and thedischarge branching pipe 89 can be reliably prevented, whereby stress acting on the first, second, and thirdcapillary tubes capillary tube 93 a and thesuction branching pipe 87 is not fixed to the fixingmember 98, but at least one of thesuction branching pipe 87, theintermediate pipe 88, and thedischarge branching pipe 89 is preferably fixed to the fixingmember 98. For example, thesuction branching pipe 87 may be fixed to the fixingmember 98 by a band member similar to theintermediate pipe 88 and thedischarge branching pipe 89, or any one of thesuction branching pipe 87, theintermediate pipe 88, and thedischarge branching pipe 89 may be fixed to the fixingmember 98. - The
outdoor controller 37 has a microcomputer, a memory and the like provided in order to control theoutdoor unit 2, and theoutdoor controller 37 is designed to be capable of exchanging control signals or the like with theindoor controller 43 of the indoor unit 4. Specifically, a controller as an operation control means for performing operation control for the air conditioner 1 is configured by theindoor controller 43 and theoutdoor controller 37. - The outdoor
refrigerant circuit 10 a, theindoor refrigerant circuit 10 b, and therefrigerant communication pipes refrigerant circuit 10 that is capable of heating and cooling a room interior and that has the main refrigerant circuit including thecompressor 22, the four-way switching valve 23, theoutdoor heat exchanger 24 as a first heat exchanger, theexpansion valve 25 as an expansion mechanism, and theindoor heat exchanger 41 as a second heat exchanger, and also has the compressor capacitycontrol operation circuit 35 connected to thecompressor 22 and used to enable the capacity of thecompressor 22 to be controlled. The air conditioner 1 of the present embodiment is designed to be capable of controlling the devices of theoutdoor unit 2 and the indoor unit 4 by a controller configured from theindoor controller 43 and theoutdoor controller 37. - First, the operation during cooling will be described using
FIGS. 1 and 3 . - During cooling, the four-
way switching valve 23 is in the state shown by the solid lines inFIG. 1 ; i.e., a state in which the discharge side of thecompressor 22 is connected to theoutdoor heat exchanger 24 and the suction side of thecompressor 22 is connected to thesecond stop valve 27. The degree of opening of theexpansion valve 25 is adjustable. Thestop valves electromagnetic coil 92 of thepilot valve 90 is in the nonconductive state. - When the
compressor 22, theoutdoor fan 36, and theindoor fan 42 are started up while therefrigerant circuit 10 is in this state, the low-pressure refrigerant is taken in by thecompressor 22 and compressed to be a high-pressure refrigerant. Since theelectromagnetic coil 92 of thepilot valve 90 is in the nonconductive state herein, the result is a state in which thesecond port 94 b and thethird port 94 c of thepilot valve 90 are brought into communication with each other, and thefirst port 94 a is not communicated with either of the second orthird ports compressor 22 without delaying the start of compression, and a full load operation is performed in which the discharge capacity is 100% with respect to the suction capacity. The high-pressure refrigerant is then fed via the four-way switching valve 23 to theoutdoor heat exchanger 24 functioning as a refrigerant cooler, heat exchange is conducted between the refrigerant and outdoor air supplied by theoutdoor fan 36, and the refrigerant is cooled. The high-pressure refrigerant cooled in theoutdoor heat exchanger 24 is depressurized by theexpansion valve 25 to be a low-pressure gas-liquid two-phase refrigerant, which is fed via thefirst stop valve 26 and the firstrefrigerant communication pipe 6 to the indoor unit 4. The low-pressure gas-liquid two-phase refrigerant fed to the indoor unit 4 is heated through heat exchange with indoor air in theindoor heat exchanger 41 functioning as a refrigerant heater, and the refrigerant is thereby evaporated to be a low-pressure refrigerant. The low-pressure refrigerant heated in theindoor heat exchanger 41 is then fed via the secondrefrigerant communication pipe 7 to theoutdoor unit 2, and is again taken in by thecompressor 22 via thesecond stop valve 27, the four-way switching valve 23, and theaccumulator 21. Thus, cooling is performed. The capacity of thecompressor 22 during the full load operation is controlled primarily by frequency control of thecompressor motor 75. - Next, the operation during heating will be described using
FIGS. 1 and 3 . - During heating, the four-
way switching valve 23 is in the state shown by the dashed lines inFIG. 1 ; i.e., a state in which the discharge side of thecompressor 22 is connected to thesecond stop valve 27, and the suction side of thecompressor 22 is connected to theoutdoor heat exchanger 24. The degree of opening of theexpansion valve 25 is adjustable. Thestop valves electromagnetic coil 92 of thepilot valve 90 is in the nonconductive state. - When the
compressor 22, theoutdoor fan 36, and theindoor fan 42 are started up while therefrigerant circuit 10 is in this state, the low-pressure refrigerant is taken in by thecompressor 22 and compressed to be a high-pressure refrigerant. Since theelectromagnetic coil 92 of thepilot valve 90 is in the nonconductive state herein, the result is a state in which thesecond port 94 b and thethird port 94 c of thepilot valve 90 are brought into communication with each other and thefirst port 94 a is not communicated with either of the second orthird ports compressor 22 without delaying the start of compression, and a full load operation is performed in which the discharge capacity is 100% with respect to the suction capacity. The high-pressure refrigerant is then fed via the four-way switching valve 23, thesecond stop valve 27, and the secondrefrigerant communication pipe 7 to the indoor unit 4. The high-pressure refrigerant fed to the indoor unit 4 is then cooled through heat exchange with indoor air in theindoor heat exchanger 41 functioning as a refrigerant cooler, and the refrigerant is then fed via the firstrefrigerant communication pipe 6 to theoutdoor unit 2. The high-pressure refrigerant fed to theoutdoor unit 2 is depressurized by theexpansion valve 25 to be a low-pressure gas-liquid two-phase refrigerant, and then flows into theoutdoor heat exchanger 24 functioning as a refrigerant heater. The low-pressure gas-liquid two-phase refrigerant that has flowed into theoutdoor heat exchanger 24 is heated through heat exchange with outdoor air supplied by theoutdoor fan 36, the refrigerant is thereby evaporated to be a low-pressure refrigerant, and the refrigerant is taken back into thecompressor 22 via the four-way switching valve 23 and theaccumulator 21. Thus, heating is performed. The capacity of thecompressor 22 during the full load operation is controlled primarily by performing frequency control of thecompressor motor 75. - <Action During Unload Operation>
- The full load operation as described above is performed in areas in which the operating efficiency of the refrigeration cycle is comparatively favorable in cases in which the ratio of the pressure of the high-pressure refrigerant with respect to the pressure of the low-pressure refrigerant in the refrigeration cycle is suppressed at a predetermined range or lower, or in cases in which the frequency of the
compressor motor 75 is in a comparatively high range. Therefore, there are many cases in which controlling the frequency of thecompressor motor 75 is sufficient to control the capacity of thecompressor 22. - However, in cases in which the ratio of the pressure of the high-pressure refrigerant with respect to the pressure of the low-pressure refrigerant in the refrigeration cycle exceeds the predetermined range, or in cases in which the frequency of the
compressor motor 75 is in a low range, conditions arise in which the capacity of thecompressor 22 cannot be sufficiently controlled merely by controlling the frequency of thecompressor motor 75, or the operation is performed in an area of poor operating efficiency. - In view of this, the
electromagnetic coil 92 of thepilot valve 90 is switched to the conductive state in such a case, creating a state in which thefirst port 94 a and thesecond port 94 b of thepilot valve 90 are brought into communication with each other, and thethird port 94 c is not communicated with either of the first orsecond ports channel 80 and thebypass channel 82 are communicated with each other and the refrigerant is guided from thecompression chamber 68 to the low-pressure space S4. Compression work is thereby performed in thecompressor 22 in a state in which the start of compression is delayed, an unload operation is performed in which the discharge capacity is reduced with respect to the suction capacity, and an operation in the state in which thecompressor motor 75 has a low frequency is avoided. - The operating efficiency can thereby be prevented as much as possible from decreasing, even in cases in which the ratio of the pressure of the high-pressure refrigerant with respect to the pressure of the low-pressure refrigerant in the refrigeration cycle exceeds the predetermined range, or in cases in which the frequency of the
compressor motor 75 is in a low range. Moreover, thepilot valve 90 is designed so that there are no situations in which some of the refrigerant discharged from thecompressor 22 is needlessly bypassed to thesuction pipe 28 from thedischarge pipe 30, similar to a case of using two two-way valves, and increases in power consumption in thecompressor 22 during the unload operation can therefore be suppressed. Furthermore, when switching between the full load operation and the unload operation, unlike a case of using two two-way valves, the number of electrical wires can be reduced and the control specifics can be simplified because it is only necessary to control just thepilot valve 90. - An embodiment of the present invention was described above with reference to the drawings, but the specific configuration is not limited to this embodiment, and modifications can be made within a range that does not deviate from the scope of the invention.
- <A>
- In the embodiment described above, the fourth
capillary tube 93 d was closed off among the four connectingcapillary tubes 93 a to 93 d of thepilot valve 90, but the present invention is not limited to this option, and any one of the four connectingcapillary tubes 93 a to 93 d can be can be closed off. In this case, the capillary tubes connected to thesuction branching pipe 87, theintermediate pipe 88, and thedischarge branching pipe 89 are changed according to the closed off capillary tube, whereby thepilot valve 90 preferably has the same flow channel configuration as one configured from two two-way valves, similar to the embodiment described above. - <B>
- In the embodiment described above, a scroll compressor was used as the
compressor 22, and thecompressor motor 75 was disposed in the high-pressure space S3 filled with high-pressure refrigerant, but the present invention is not limited to this option, and a rotary compressor or another such compressor may be used, and thecompressor motor 75 may be disposed in a space filled with low-pressure refrigerant. - <C>
- In the embodiment described above, the
outdoor unit 2 had a design in which the interior of theunit casing 51 was divided by thepartitioning plate 56 into the air blower chamber S1 and the machinery chamber S2 and the air taken into theunit casing 51 was blown out from the front surface of theunit casing 51, but the present invention is not limited to this option, and another type of outdoor unit may be used, such as an outdoor unit having a design in which air taken into the unit casing is blown out from the top surface of the unit casing. In the embodiment described above, the air conditioner 1 was a so-called paired and separated type air conditioner in which one indoor unit 4 was connected to oneoutdoor unit 2, but other types of air conditioner may also be used, such as a remote-condenser type air conditioner or a multi-type air conditioner in which a plurality of indoor units are connected to one or more outdoor unit. - Utilizing the present invention makes it possible to provide a compressor capacity control operation mechanism and an air conditioner comprising the mechanism wherein cost increases can be prevented and the capacity of the compressor can be controlled in the same manner as in a case of using two two-way valves.
Claims (8)
1. A compressor capacity control operation mechanism configured to be connected to a compressor and to control capacity of the compressor; the compressor capacity control operation mechanism comprising:
a flow channel switching valve including
a valve main body having a flow channel configuration switchable between
a first state in which a first flow channel and a second flow channel are connected and a third flow channel is not connected to either the first flow channel or the second flow channel, and
a second state in which the second flow channel and the third flow channel are connected and the first flow channel is not connected to either the second flow channel or the third flow channel; with
a first capillary tube forming the first flow channel and extending from the valve main body;
a second capillary tube forming the second flow channel and extending from the valve main body; and
a third capillary tube forming the third flow channel and extending from the valve main body;
a suction branching pipe branching off from a suction pipe of the compressor and having a larger diameter than the first capillary tube, the suction branching pipe being connected to the first capillary tube;
an intermediate pipe connected to a cylinder intermediate part of the compressor and having a larger diameter than the second capillary tube, the intermediate pipe being connected to the second capillary tube;
a discharge branching pipe branching off from a discharge pipe of the compressor and having a larger diameter than the third capillary tube, the discharge branching pipe being connected to the third capillary tube; and
a fixing member having
the flow channel switching valve fixed thereto, and
at least one of the suction branching pipe, the intermediate pipe, and the discharge branching pipe fixed thereto.
2. The compressor capacity control operation mechanism according to claim 1 , wherein
the at least one of the suction branching pipe, the intermediate pipe, and the discharge branching pipe fixed to the fixing member being fixed to the fixing member in proximity to the capillary tube connected thereto.
3. A compressor capacity control operation mechanism configured to control compressor capacity; the compressor capacity control operation mechanism comprising:
a first pilot valve having four connecting capillary tubes connected thereto, the first pilot valve being operable as a first four-way switching valve;
a suction branching pipe connected to a first capillary tube of the four connecting capillary tubes and branched off from a compressor suction pipe;
an intermediate pipe connected to a second capillary tube of the four connecting capillary tubes and connected to a compressor cylinder intermediate part; and
a discharge branching pipe connected to a third capillary tube of the four connecting capillary tubes and branched off from a compressor discharge pipe.
4. The compressor capacity control operation mechanism according to claim 3 , wherein
a fourth capillary tube of the four connecting capillary tubes is closed off.
5. An air conditioner including the compressor capacity control operation mechanism according to claim 3 , the air conditioner further comprising:
a vapor-compression main refrigerant circuit including
a compressor,
a switching valve including a second pilot valve operable as a second four-way switching valve,
a first heat exchanger,
an expansion mechanism, and
a second heat exchanger, with
the first pilot valve operable as the first four-way switching valve being identical to the second pilot valve operable as the second four-way switching valve.
6. An air conditioner including the compressor capacity control operation mechanism according to claim 4 , the air conditioner further comprising:
a vapor-compression main refrigerant circuit including
a compressor,
a four-way switching valve,
a first heat exchanger,
an expansion mechanism, and
a second heat exchanger, with
the first pilot valve operable as the first four-way switching valve being identical to the second pilot valve operable as the second four-way switching valve.
7. The compressor capacity control operation mechanism according to claim 3 , further comprising
a fixing member having
the first pilot valve fixed thereto, and
at least one of the suction branching pipe, the intermediate pipe, and the discharge branching pipe fixed thereto; wherein
the first pilot valve includes a valve main body having a flow channel configuration switchable between
a first state in which the first and second capillary tubes are connected and the third capillary tube is not connected to either the first capillary tube or the second capillary tube, and
a second state in which the second and third capillary tubes are connected and the first capillary tube is not connected to either the second capillary tube or the third capillary tube;
the suction branching pipe has a larger diameter than the first capillary tube;
the intermediate pipe has a larger diameter than the second capillary tube;
the discharge branching pipe has a larger diameter than the third capillary tube.
8. The compressor capacity control operation mechanism according to claim 7 , wherein
the at least one of the suction branching pipe, the intermediate pipe, and the discharge branching pipe fixed to the fixing member is fixed to the fixing member in proximity to the capillary tube connected thereto.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2007-085368 | 2007-03-28 | ||
JP2007085368A JP2008240699A (en) | 2007-03-28 | 2007-03-28 | Compressor displacement control operation mechanism, and air conditioning device provided with same |
PCT/JP2008/055367 WO2008123171A1 (en) | 2007-03-28 | 2008-03-24 | Mechanism for controlling and operating compressor capacity and air conditioner having the same |
Publications (1)
Publication Number | Publication Date |
---|---|
US20100037642A1 true US20100037642A1 (en) | 2010-02-18 |
Family
ID=39830668
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/531,099 Abandoned US20100037642A1 (en) | 2007-03-28 | 2008-03-24 | Compressor capacity control operation mechanism and air conditioner provided with same |
Country Status (7)
Country | Link |
---|---|
US (1) | US20100037642A1 (en) |
EP (1) | EP2143952A4 (en) |
JP (1) | JP2008240699A (en) |
KR (1) | KR101212642B1 (en) |
CN (1) | CN101652570A (en) |
AU (1) | AU2008236150B2 (en) |
WO (1) | WO2008123171A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120255323A1 (en) * | 2011-04-07 | 2012-10-11 | Juhyok Kim | Air conditioner |
US20140318165A1 (en) * | 2011-12-13 | 2014-10-30 | Daikin Industries, Ltd. | Refrigeration apparatus |
CN115917157A (en) * | 2020-07-01 | 2023-04-04 | 大金工业株式会社 | Heat source unit and scroll compressor |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2012247097A (en) * | 2011-05-26 | 2012-12-13 | Panasonic Corp | Refrigerating cycle apparatus |
JP5971633B2 (en) * | 2011-05-26 | 2016-08-17 | パナソニックIpマネジメント株式会社 | Refrigeration cycle equipment |
FR2976052B1 (en) * | 2011-06-06 | 2013-06-28 | Gen Accessoires De Chauffage Gac | CONTROLLED MECHANICAL VENTILATION OF DOUBLE TYPE REVERSIBLE THERMODYNAMIC FLOW |
JP5976333B2 (en) * | 2012-02-13 | 2016-08-23 | 三菱重工業株式会社 | Air conditioner and four-way valve control method for air conditioner |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20060093504A1 (en) * | 2004-11-04 | 2006-05-04 | Lg Electronics Inc. | Apparatus for varying capacity of scroll compressor |
US20080193310A1 (en) * | 2005-02-23 | 2008-08-14 | Lg Electronics Inc. | Capacity Varying Type Rotary Compressor and Refrigeration System Having the Same |
US7870752B2 (en) * | 2004-07-27 | 2011-01-18 | Emerson Electric Gmbh & Co. Ohg | Heat extraction machine and a method of operating a heat extraction machine |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6245993A (en) * | 1985-08-24 | 1987-02-27 | Toyoda Autom Loom Works Ltd | Volume control mechanism for variable delivery compressor |
JPS6346761U (en) * | 1986-09-10 | 1988-03-30 | ||
JPH02191882A (en) * | 1989-01-20 | 1990-07-27 | Hitachi Ltd | Displacement control device for compressor and control method thereof |
JPH05340485A (en) * | 1992-06-05 | 1993-12-21 | Hitachi Ltd | Control valve |
JPH062688A (en) * | 1992-06-19 | 1994-01-11 | Matsushita Refrig Co Ltd | Refrigerant compressor |
JPH1114097A (en) * | 1997-06-20 | 1999-01-22 | Fujitsu General Ltd | Outdoor unit of air conditioner |
JP2002147627A (en) * | 2000-11-07 | 2002-05-22 | Fuji Koki Corp | Change-over valve |
JP3698132B2 (en) * | 2002-08-26 | 2005-09-21 | ダイキン工業株式会社 | Air conditioner |
-
2007
- 2007-03-28 JP JP2007085368A patent/JP2008240699A/en active Pending
-
2008
- 2008-03-24 EP EP08722683.3A patent/EP2143952A4/en not_active Withdrawn
- 2008-03-24 KR KR1020097021309A patent/KR101212642B1/en not_active IP Right Cessation
- 2008-03-24 AU AU2008236150A patent/AU2008236150B2/en not_active Ceased
- 2008-03-24 US US12/531,099 patent/US20100037642A1/en not_active Abandoned
- 2008-03-24 CN CN200880010351A patent/CN101652570A/en active Pending
- 2008-03-24 WO PCT/JP2008/055367 patent/WO2008123171A1/en active Application Filing
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7870752B2 (en) * | 2004-07-27 | 2011-01-18 | Emerson Electric Gmbh & Co. Ohg | Heat extraction machine and a method of operating a heat extraction machine |
US20060093504A1 (en) * | 2004-11-04 | 2006-05-04 | Lg Electronics Inc. | Apparatus for varying capacity of scroll compressor |
US20080193310A1 (en) * | 2005-02-23 | 2008-08-14 | Lg Electronics Inc. | Capacity Varying Type Rotary Compressor and Refrigeration System Having the Same |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120255323A1 (en) * | 2011-04-07 | 2012-10-11 | Juhyok Kim | Air conditioner |
US20140318165A1 (en) * | 2011-12-13 | 2014-10-30 | Daikin Industries, Ltd. | Refrigeration apparatus |
EP2792971A4 (en) * | 2011-12-13 | 2015-10-07 | Daikin Ind Ltd | Refrigeration device |
US9464830B2 (en) * | 2011-12-13 | 2016-10-11 | Daikin Industries, Ltd. | Refrigeration apparatus for executing a pump down |
CN115917157A (en) * | 2020-07-01 | 2023-04-04 | 大金工业株式会社 | Heat source unit and scroll compressor |
US11802721B2 (en) * | 2020-07-01 | 2023-10-31 | Daikin Industries, Ltd. | Heat source unit and scroll compressor |
Also Published As
Publication number | Publication date |
---|---|
KR101212642B1 (en) | 2012-12-14 |
CN101652570A (en) | 2010-02-17 |
AU2008236150B2 (en) | 2011-04-28 |
JP2008240699A (en) | 2008-10-09 |
EP2143952A1 (en) | 2010-01-13 |
AU2008236150A1 (en) | 2008-10-16 |
KR20090130043A (en) | 2009-12-17 |
EP2143952A4 (en) | 2015-06-17 |
WO2008123171A1 (en) | 2008-10-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20100037642A1 (en) | Compressor capacity control operation mechanism and air conditioner provided with same | |
KR100741241B1 (en) | Refrigerating apparatus and refrigerator | |
JP5556499B2 (en) | Two-stage boost refrigeration cycle | |
EP2578886B1 (en) | Scroll compressor and air conditioner including the same | |
JP2007232263A (en) | Refrigeration unit | |
AU756840B2 (en) | Air conditioner | |
JP4219198B2 (en) | Refrigerant cycle equipment | |
US10563891B2 (en) | Variable displacement scroll compressor | |
WO2020202515A1 (en) | Compressor and air conditioner | |
EP3043125B1 (en) | Air conditioner | |
EP1426710B1 (en) | Refrigerant cycling device | |
JP5515289B2 (en) | Refrigeration equipment | |
JP2010156498A (en) | Refrigerating device | |
JP2007113447A (en) | Expander integrated compressor and refrigeration cycle device | |
JP2006177194A (en) | Multiple cylinder rotary compressor | |
JP2012002473A (en) | Fluid compression device, and heat pump cycle using the same | |
JP2006169978A (en) | Multi-cylinder rotary compressor | |
JP7445623B2 (en) | Scroll compressor and refrigeration cycle equipment | |
WO2024069829A1 (en) | Scroll compressor and air conditioner | |
EP2169180A1 (en) | Fluid machine | |
JP4055264B2 (en) | Air conditioner | |
JP2006275035A (en) | Refrigerating device, refrigerator and compressor | |
JP2003106741A (en) | Defrosting device of refrigerant circuit | |
CN115371310A (en) | Gas-liquid separator, compressor assembly and air conditioner with compressor assembly | |
KR101206575B1 (en) | Air Conditioner |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: DAIKIN INDUSTRIES, LTD.,JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SHIMODA, JUNICHI;TAKEICHI, HISASHI;UKAI, TAKEOMI;AND OTHERS;SIGNING DATES FROM 20080414 TO 20080524;REEL/FRAME:023224/0276 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO PAY ISSUE FEE |