JPH1183214A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To materialize the capacity control in multistage while materializing the reduction of energy consumption and the curtailment of the number of constituent parts. SOLUTION: A refrigerant pipe 23 (high-pressure circuit) and a refrigerant pipe 32 (low-pressure circuit) are connected with each other by a supply pipe 41, and further the first to third introduction pipes 42-44 are branched in order from the side of the refrigerant pipe 23 from the supply pipe 41. The first to third pipes 42-44 are connected all to the first compressor 3, as the drive sources for a power control mechanism. Moreover, in the supply pipe 41, normal-close type of first to third shutoff valves 45-47 on high pressure side are interposed on the side of the refrigerant pipe 23 from each divergence position of the first to third introduction pipe 42-44, and also a normal-close shutoff valve on low pressure side is interposed on the side of the refrigerant pipe 32 from the divergence position of the third introduction pipe 44.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner equipped with a variable capacity compressor and a constant capacity compressor on a heat source side, while reducing energy consumption and the number of constituent parts. The present invention relates to a technology for achieving capability control at a stage.

[0002]

2. Description of the Related Art In recent air conditioners, in order to prevent overshooting and hunting at room temperature during cooling and heating, capacity control is performed on a heat source side (compressor) according to a capacity requirement on a user side (indoor heat exchanger). Is the mainstream. As a method of controlling the capacity of a compressor, there are many methods of converting the frequency of AC power using an inverter device and thereby linearly controlling the driving rotation speed of the compressor. According to this method, since the capacity of the compressor can be arbitrarily varied from 0 to the rated point, substantially perfect air conditioning control can be realized. However, the inverter device has various problems such as inevitable energy loss due to frequency conversion, emission of undesired higher harmonics to the environment, and increase in device cost for large inverter devices.

In Japanese Patent Application Laid-Open No. Hei 8-247560, a power control mechanism is incorporated into one constant speed compressor while using two constant speed compressors having a compression mechanism driven at a constant speed. A variable capacity compressor (hereinafter, referred to as a PC compressor) and further provided with a refrigerant return circuit has been proposed. The power control mechanism is
A valve device is attached to the cylinder side wall of the compression mechanism.
By opening this valve device, for example, compression work in the first half of the compression stroke is not performed. The power control mechanism uses a high pressure and a low pressure as a driving source, and introduces pressure supply piping that connects the high pressure circuit and the low pressure circuit, or branches from the pressure supply piping to supply pressure to the power control mechanism. Piping and the like are provided in the apparatus. In the pressure supply pipe, a high-pressure side shut-off valve is interposed on the high-pressure circuit side, and a low-pressure side shut-off valve is interposed on the low-pressure circuit side, and these shut-off valves are opened and closed by a control device. Further, the refrigerant return circuit, for example, by providing a bypass pipe between the discharge-side refrigerant circuit and the suction-side refrigerant circuit of both compressors, by opening a shut-off valve interposed in this bypass pipe, after compression, Part of the high-pressure refrigerant gas is returned to the suction-side refrigerant circuit.

When a PC compressor and a normal constant speed compressor are combined, multi-stage capacity control is performed by operating or stopping both compressors individually or by driving a power control mechanism and a refrigerant return circuit. It becomes possible. For example,
Assuming that the rated capacity of the PC compressor is 4 hp, the rated capacity of the constant speed compressor is 6 hp, the capacity reduction of the PC compressor by the power control mechanism is 2 hp, and the capacity reduction by the refrigerant return circuit is 1 hp, The ability can be switched every 1 horsepower (that is, 10 steps) in the range of 1 to 10 horsepower.

[0005]

When the above-described refrigerant return circuit is opened, a part of the compressed high-pressure refrigerant gas flows back to the suction-side refrigerant circuit, so that the compressor performs unnecessary compression work. become. For example, when operating at a capacity of 9 hp, compression work of 1 hp is discarded by the refrigerant return circuit, but energy consumption is substantially the same as when operating at a capacity of 10 hp. As a result, the same or more energy loss as in the case of using the inverter device occurs, and this is a factor that makes it difficult to employ a PC compressor. In addition, although it was considered that the capacity control was performed only by the power control mechanism without providing the refrigerant return circuit, in such a case, in the above-described compressor configuration, the capacity switching was performed every two horsepower (that is, five stages). Would. Therefore, in an air conditioner, when the capacity demand on the user side is small (for example, about 1 to 3 horsepower), overshoot and hunting at room temperature are likely to occur,
There is a possibility that the user's comfort in the conditioned space may be impaired.

Accordingly, the present inventors have developed a PC compressor capable of performing four-stage capacity control using the compressor body, and by combining this with a normal constant-speed compressor (constant-capacity compressor), a large number of compressors have been developed. An air conditioner in which the frequency of use of the refrigerant return circuit has been reduced while performing stepwise capacity control has been realized. That is,
P whose ability can be switched every 1 hp in the range of 1-4 hp
By manufacturing a C compressor and combining it with a constant speed compressor having a capacity of 6 horsepower, the refrigerant return circuit can be operated for 5 horsepower while controlling the capacity in 10 steps as in the above-described conventional apparatus. Only when was able to. As a result, the frequency of discarding the compression work is reduced and energy consumption is naturally reduced, but this time, a problem has arisen that the pressure supply system for the power control mechanism is complicated and expensive.

That is, in order for the PC compressor to perform four-stage capacity control, three power control mechanisms are required, and these power control mechanisms must be individually driven and controlled. Therefore, when the same method as that of the conventional apparatus is adopted, three pressure supply pipes and three introduction pipes are provided in the apparatus, and three high pressure side shut-off valves and three low pressure side shut-off valves are provided. It is provided for each pressure supply pipe. As a result, the layout of the piping and equipment in the apparatus becomes extremely complicated, and the number of steps required for assembly and maintenance and the cost of products are inevitably increased.

The present invention has been made in view of the above circumstances, and has as its object to provide an air conditioner that realizes multi-stage capability control while reducing energy consumption and the number of components. .

[0009]

Therefore, according to the present invention, a variable capacity compressor whose capacity is controlled in three or more stages by a plurality of power control mechanisms is provided on a heat source side.
An air conditioner in which each of the power control mechanisms is driven by a high pressure supplied from a high pressure circuit and a low pressure supplied from a low pressure circuit. The present invention proposes a device provided with a single pressure supply pipe for supplying pressure and a plurality of shut-off valves interposed in the pressure supply pipe.

In the present invention, for example, when the power control mechanism is to reduce the capacity of the compressor by supplying low-pressure refrigerant gas, when the compressor is operated at a predetermined capacity or more, the shut-off valve is opened and each of the compressors is opened. When a high-pressure pressure such as a high-pressure refrigerant gas can be supplied to the power control mechanism and the compressor is operated with the minimum capacity, the shut-off valve is closed to stop the supply of the high-pressure pressure to all the power control mechanisms.

Further, in the air conditioner of the present invention, the pressure supply pipe is connected to the low pressure circuit, branched from the pressure supply pipe at different positions, and supplies a high pressure to each of the power control mechanisms. A plurality of introduction pipes, a high-pressure side cutoff valve provided corresponding to each of these introduction pipes, and interposed in the pressure supply pipe on the high-pressure circuit side from a branch position of each introduction pipe; And a low-pressure side cutoff valve interposed in the pressure supply pipe on the side of the low-pressure circuit from the branch position of the introduction pipe.

For example, in the case where the compressor is provided with three power control mechanisms, when the compressor is operated at the maximum capacity, each high-pressure side shut-off valve is opened and the low-pressure side shut-off valve is closed. Is supplied with a high pressure such as a high pressure refrigerant gas. When the compressor is operated at the minimum capacity, the high pressure side shutoff valve from the highest pressure circuit is closed while the other high pressure side shutoff valve and the low pressure side shutoff valve are opened, and all the power control mechanisms are operated at low pressure. A low pressure such as a refrigerant gas is supplied. When the compressor is operated at the intermediate capacity, one or two power control units are opened by opening the high-pressure side shutoff valve and the low-pressure side shutoff valve from the highest pressure circuit and opening and closing the other high pressure side shutoff valves as appropriate. Have the mechanism supply a low pressure.

Further, in the present invention, the high pressure side shut-off valve provided in the refrigerant gas supply pipe and the number corresponding to the respective power control mechanisms are provided and connected to the refrigerant gas supply pipe. A communication pipe for communication between the circuit and the low-pressure refrigerant circuit; an introduction pipe branched from each of the communication pipes one by one to guide a refrigerant gas to a corresponding power control mechanism; A circuit having a low-pressure side shut-off valve interposed in each communication pipe on the circuit side is proposed.

In the present invention, for example, in the case where the compressor is provided with three power control mechanisms, when the compressor is operated at the maximum capacity, the high-pressure side shut-off valve is opened and each low-pressure side shut-off valve is opened. Close and allow all power control mechanisms to supply high pressure refrigerant gas. Also,
When the compressor is operated at the minimum capacity, the high pressure side shutoff valve is closed and the low pressure side shutoff valves are opened to supply the low pressure refrigerant gas to all the power control mechanisms.
When the compressor is operated at the intermediate capacity, the high-pressure side shut-off valve is opened while the low-pressure side shut-off valves are appropriately opened, and the low-pressure refrigerant gas is supplied to one or two power control mechanisms.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, two embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of an air-conditioning system according to a first embodiment including one outdoor unit 1 and a plurality of indoor units 2. In FIG. 1, a refrigeration cycle is indicated by a solid line, and an alternate long and short dash line. Indicates a control / signal system.

On the outdoor unit 1 side, first and second compressors 3 and 4, an electromagnetic four-way valve 5, an outdoor heat exchanger 6, an electric fan 7, an accumulator 8, an oil separator 9 and the like are installed. . An electric expansion valve 11, an indoor heat exchanger 12, an electric fan 13, and the like are installed on each indoor unit 2 side. Among these devices, those constituting a refrigeration cycle are connected by refrigerant pipes 21 to 36 provided for the flow of gas refrigerant or liquid refrigerant. In the figure,
Non-return valves 15 and 16 for preventing the refrigerant from flowing back to the compressors 3 and 4 are interposed in the refrigerant pipes 21 and 22, respectively.

In the case of the first embodiment, the refrigerant pipe 23 forming the high-pressure refrigerant circuit and the refrigerant pipe 3 forming the low-pressure refrigerant circuit
2 is communicated by a refrigerant gas (pressure) supply pipe (hereinafter abbreviated as a supply pipe) 41.
1 to the first to third introduction pipes 4 in order from the refrigerant pipe 23 side.
2-44 are branched. First to third introduction pipes 42 to 4
4 are all connected to the first compressor 3 as drive sources for a power control mechanism described later. Further, the supply pipe 41 is provided with normally-closed first to third high-pressure side shut-off valves 45 to 47 which are interposed from the refrigerant pipe 23 from respective branch positions of the first to third introduction pipes 42 to 44. A normally-closed low-pressure side shut-off valve 48 is also interposed between the refrigerant pipe 32 and the branch position of the 3 introduction pipe 44. In the figure, reference numeral 49 denotes a capillary tube, which is a low pressure side shutoff valve 48 in the supply pipe 41.
And a refrigerant pipe 32.

The outdoor unit 1 includes an outdoor control unit (hereinafter referred to as an outdoor ECU) including a CPU, an input / output interface, a ROM, a RAM, and the like.
51) are provided. The outdoor ECU 51 includes:
Based on input information from a built-in control program and various sensors (not shown), the compressors 3, 4 and the four-way valve 5, the electric fan 7, and the shut-off valves 45 to 48 are drive-controlled.

On the other hand, in each indoor unit 2, an indoor control unit (hereinafter referred to as an indoor ECU) 53 including a CPU, an input / output interface, a ROM, a RAM and the like is installed. Indoor ECU5
2 controls driving of the electric expansion valve 11 and the electric fan 13 based on input signals from a built-in control program, a remote controller (not shown), various sensors, and the like, and communicates with the outdoor ECU 51 via the bus line 55. To exchange signals with each other.

In the case of the first embodiment, each of the first and second compressors 3 and 4 is an electric twin rotor type constant speed compressor having a pair of upper and lower rotary compression elements. The output is 4 hp, and the rated output on the second compressor 4 side is 6 hp. The first compressor 3 is a PC compressor provided with a power control mechanism, and can switch the output between 1 to 4 horsepower every one horsepower.

Hereinafter, the structure of the power control mechanism according to the first embodiment will be described.

The compression mechanism 61 of the first compressor 3 includes a pair of upper and lower cylinders 69 and 70 sandwiched between a main frame 65 and a bearing plate 67, and both cylinders 69, as shown in FIG. , 70 and a pair of upper and lower cylinder chambers 73, 7 defined by the intermediate plate 71.
5 and a pair of upper and lower rotors 77 and 79 which eccentrically rotate with a phase difference of 180 ° while slidingly contacting the inner peripheral surfaces of the two cylinder chambers 73 and 75. In the figure, reference numeral 80 denotes a compressor casing.

The power control mechanism 81 communicates the two cylinder chambers 73 and 75 at three communicating portions (portions which are out of phase by 90 ° and 180 ° with respect to a vane described later). A valve hole 83 penetrating vertically through the outer periphery of the intermediate plate 71, a pair of upper and lower piston valves 85, 86 slidably held in the valve hole 83,
A main component is a valve spring (compression coil spring) 87 that urges the pumps 86 away from each other. In the intermediate plate 71, the inner diameter of the valve hole 83 is smaller than the outer diameter of the piston valves 85 and 86 so as to form stoppers for the piston valves 85 and 86. Further, the valve spring 87 is completely compressed when a high pressure (for example, 20% of the maximum discharge pressure of the first compressor 3) acts on the pressure receiving surfaces of the piston valves 85 and 86 at a predetermined value or more. Is set.

The valve hole 83 communicates with the two cylinder chambers 73 and 75 through a pair of communication holes 88 and 89 formed near the intermediate plate 71. In both cylinders 69, 70 and intermediate plate 71, valve holes 83 are provided.
A gas refrigerant from the introduction pipe 42 (43, 44) is introduced into the refrigerant introduction hole 91. Further, communication recesses 93 and 94 are formed in the main frame 65 and the bearing plate 67 to communicate the valve hole 83 and the coolant introduction hole 91, respectively.

When the low-pressure refrigerant gas is introduced into the refrigerant introduction hole 91, the piston valves 85 and 86 are actuated by the spring force of the valve spring 87, as shown in FIG. Pressed to. As a result, both cylinder chambers 73 and 75
The gas refrigerant flows through the communication holes 88 and 89, the valve hole 83, and the check valve 90, and flows out of the compression space of one cylinder chamber 75 (73) into the suction space of the other cylinder chamber 73 (75). On the other hand, when high-pressure refrigerant gas is introduced into the refrigerant introduction hole 91, a high pressure acts on the pressure receiving surfaces of the piston valves 85 and 86, and the valve spring 87 is compressed. It comes into contact with the plate 71. As a result, both piston valves 85, 8
The communication holes 88 and 89 are closed by the outer peripheral surface of 6, and the communication between the two cylinder chambers 73 and 75 is stopped.

FIG. 4 is a schematic diagram showing an arrangement of the power control mechanism 81 with respect to the compression mechanism 61, and FIG. 5 is a schematic diagram showing a refrigerant gas circuit and a control system for each power control mechanism 81. As described above, the power control mechanism 81 is disposed at a position shifted by 90 ° and 180 ° with respect to the vane 95, respectively.
The first introduction pipe 42 is connected to the power control mechanism 81 on the discharge port 97 side, and the second introduction pipe 43 is connected to the power control mechanism 81 facing the vane 95.
The third introduction pipe 44 is connected to the power control mechanism 81 on the suction port 98 side.

Hereinafter, the capacity of the outdoor unit 1 and the ON / OF of the first and second compressors 3 and 4 and the shutoff valves 45 to 48 will be described.
Referring to the table of FIG. 6 showing the relationship with the F state,
The operation of the first embodiment will be described.

In the first embodiment, when the power control mechanism 81 is operated, the outdoor ECU 51 sets
The third high pressure side cutoff valves 45 to 47 and the low pressure side cutoff valve 48 are appropriately driven and controlled. For example, the first to third high pressure side shutoff valves 45
If the low pressure side shut-off valve 48 is closed (OFF operation) by opening the low pressure side shut-off valve 48 (ON operation), the high pressure refrigerant gas in the refrigerant pipe 23 is first to the first pressure as shown by the solid arrow in FIG. Third
The power is introduced into each power control mechanism 81 through the introduction pipes 42 to 44, whereby the two cylinder chambers 73 and 75 are introduced.
All communication between them is cut off, and the first compressor 3 performs a compression work of 4 hp during its operation. When the low-pressure side shutoff valve 48 is opened (ON operation) from this state, the low-pressure refrigerant gas in the refrigerant pipe 32 is introduced into the power control mechanism 81 on the suction port 98 side through the third introduction pipe 44, As a result, the communication between the two cylinder chambers 73 and 75 is interrupted by 3/4, and the first compressor 3 is turned off during operation.
It will do the work of compressing horsepower.

When the third high-pressure side shut-off valve 47 is further opened (ON operation) from this state, the power control in which the low-pressure refrigerant gas in the refrigerant pipe 32 faces the vane 95 via the second introduction pipe 43. It is also introduced into the mechanism 81, whereby the communication between the two cylinder chambers 73 and 75 is cut off by half, and the first compressor 3 performs a compression work of 2 hp during its operation. Then, when the second high-pressure side shut-off valve 47 is further opened (ON operation) from this state, the low-pressure refrigerant gas in the refrigerant pipe 32 becomes the first to third introduction pipes 42 to 44.
, The communication between the two cylinder chambers 73 and 75 is cut off by ４, and the first compressor 3 performs 1 hp compression work during its operation. become.

The outdoor ECU 51 provides the outdoor unit 1 with 1
When the capacity of 10 to 10 hp is generated, the operation control of the first and second compressors 3 and 4 and the drive control of the power control mechanism 81 are performed as follows. That is, while operating only the first compressor 3, the first to third high-pressure side shutoff valves 45 to 47
By driving and controlling the low-pressure side shut-off valve 48 in the above-described procedure, it is possible to obtain the capability for each 1 hp between 1 and 4 hp. In addition, if only the second compressor 4 is operated, a capacity of 6 horsepower can be naturally obtained. And
While operating the first and second compressors 3 and 4 simultaneously, the first
By driving and controlling the third to third high pressure side shutoff valves 45 to 47 and the low pressure side shutoff valve 48, it is possible to obtain a capacity for each 1 hp from 7 to 10 hp.

In the first embodiment, when the outdoor unit 1 is to generate a power of 5 hp, the outdoor ECU 51 is provided with the second ECU.
At the same time that only the compressor 4 is operated, all of the first to third high-pressure side shutoff valves 45 to 47 and the low-pressure side shutoff valve 48 are opened (O
N operation). Then, the refrigerant pipe 23 and the refrigerant pipe 32
The high-pressure refrigerant gas flowing through the refrigerant pipe 23 flows out to the refrigerant pipe 32 side, as indicated by a broken arrow in FIG. 5, and the compression performed by the second compressor 4 is performed. Some of the work will be wasted. That is, the supply pipe 41 has the same operation as the refrigerant return circuit in the conventional device when the first to third high-pressure side shutoff valves 45 to 47 and the low-pressure side shutoff valve 48 are all opened. is there. When only the second compressor 4 is operated, the capillary tube 49 interposed in the supply pipe 41 becomes one.
It is set so that a high-pressure gas refrigerant for horsepower is circulated.

Next, a second embodiment of the present invention will be described. The second embodiment starts with the overall configuration of the air conditioner.
The structures of the first compressor 3 and the power control mechanism 81 are the same as those of the first embodiment. FIG. 7 is a schematic diagram illustrating a refrigerant gas circuit and a control system for each power control mechanism 81 in the second embodiment. In the case of the second embodiment, as shown in FIG. 7, the refrigerant pipe 23 (high-pressure refrigerant circuit)
And the refrigerant pipe 32 (low-pressure refrigerant circuit) are communicated by a supply pipe 41 in which a normally-closed high-pressure side shutoff valve 101 is interposed and first to third communication pipes 105 to 107 connected thereto. .

From the first communication pipe 105, the first introduction pipe 4
2 is branched, a first capillary tube 111 is provided on the refrigerant pipe 23 side from the branch position, and a normally-closed first low-pressure side shutoff valve 102 is provided on the refrigerant pipe 32 side from the branch position. Is equipped. Further, a second introduction pipe 43 branches from the second communication pipe 106, a second capillary tube 112 is interposed on the refrigerant pipe 23 side from the branch position, and a second capillary pipe 112 is interposed on the refrigerant pipe 32 side from the branch position. A normally closed second low pressure side shutoff valve 103 is interposed. And
A third introduction pipe 44 branches from the third communication pipe 107, and a third capillary tube 113 is interposed on the refrigerant pipe 23 side from the branch position, and is normally closed on the refrigerant pipe 32 side from the branch position. A third low pressure side shutoff valve 104 of a type is interposed. The high-pressure side cutoff valve 101 and the first to third low-pressure side cutoff valves 102 to 104 are all connected to the outdoor ECU 5.
1 is driven and controlled. In the case of the present embodiment, the flow resistance of the first capillary tube 111 is set relatively small, and the second and third capillary tubes 112 and 11 are set.
The circulation resistance of No. 3 is set relatively large.

Hereinafter, the capacity of the outdoor unit 1 and the ON / OFF of the first and second compressors 3 and 4 and each of the shut-off valves 101 to 104 will be described.
The operation of the second embodiment will be described with reference to the table of FIG. 8 showing the relationship with the OFF state.

In the second embodiment, when the power control mechanism 81 is operated, the outdoor ECU 51 includes the high-pressure side shutoff valve 101 and the first to third low-pressure side shutoff valves 102 to 104.
Are appropriately controlled. For example, the high pressure side cutoff valve 101 is opened (ON operation), and the first to third low pressure side cutoff valves 10 are opened.
When the valves 2 to 104 are closed (OFF operation), the high-pressure refrigerant gas in the refrigerant pipe 23 is controlled by the power control via the first to third introduction pipes 42 to 44 as shown by solid arrows in FIG. The communication between the two cylinder chambers 73 and 75 is completely interrupted, and the first compressor 3
Will perform 4 hp compression work during its operation.

In this state, the third low-pressure side cutoff valve 10
4 is opened (ON operation), the low-pressure refrigerant gas in the refrigerant pipe 32 flows into the third communication pipe 107 and the third introduction pipe 44.
Power control mechanism 8 on the suction port 98 side through the
1, the communication between the two cylinder chambers 73 and 75 is cut off by 3/4, and the first compressor 3 performs a compression work of 3 hp during its operation. At this time, the refrigerant pipe 23 and the refrigerant pipe 32 communicate with each other through the supply pipe 41 and the third communication pipe 107. However, since the flow resistance of the third capillary tube 113 is large, the refrigerant pipe 23 has Of the high-pressure refrigerant gas to the refrigerant pipe 32 side is negligible.

When the second low-pressure side shut-off valve 103 is further opened (ON operation) from this state, the low-pressure refrigerant gas in the refrigerant pipe 32 is vaned via the second communication pipe 106 and the second introduction pipe 43. 95 is also introduced into the power control mechanism 81 opposed to the first and second cylinder chambers 7.
The communication between the first and third compressors 3 and 75 is blocked by half.
Will perform 2 hp compression work during its operation. At this time, the refrigerant pipe 23 and the refrigerant pipe 32 are communicated with each other through the supply pipe 41 and the second communication pipe 106. However, since the flow resistance of the second capillary tube 112 is large, the refrigerant pipe The amount of the high-pressure refrigerant gas in the pipe 23 flowing out to the refrigerant pipe 32 is negligible.

Then, the high pressure side shutoff valve 101 is closed (OF).
F operation), and the first to third low pressure side shutoff valves 102 to 10
4 is opened (ON operation), the low-pressure refrigerant gas in the refrigerant pipe 32 is supplied to each power control mechanism 81 via the first to third communication pipes 105 to 107 and the first to third introduction pipes 42 to 44. Is introduced, which allows both cylinder chambers 7
1/4 of the communication between the first and third compressors 3 and 75 is interrupted.
Will perform 1 hp compression work during its operation.

The outdoor ECU 51 provides the outdoor unit 1 with 1
When the capacity of 10 to 10 hp is generated, the operation control of the first and second compressors 3 and 4 and the drive control of the power control mechanism 81 are performed as follows. That is, while operating only the first compressor 3, the first to third high-pressure side shutoff valves 45 to 47
By driving and controlling the low-pressure side shut-off valve 48 in the above-described procedure, it is possible to obtain the capability for each 1 hp between 1 and 4 hp. In addition, if only the second compressor 4 is operated, a capacity of 6 horsepower can be naturally obtained. And
While operating the first and second compressors 3 and 4 simultaneously, the first
By driving and controlling the third to third high pressure side shutoff valves 45 to 47 and the low pressure side shutoff valve 48, it is possible to obtain a capacity for each 1 hp from 7 to 10 hp.

In the second embodiment, when the outdoor unit 1 is to be capable of generating 5 horsepower, the outdoor ECU 51 is provided with the second ECU.
At the same time as operating only the compressor 4,
1 and the first low pressure side shutoff valve 102 are opened (ON operation). Then, the refrigerant pipe 23 and the refrigerant pipe 32 are connected by the supply pipe 41 and the first communication pipe 105, and the flow resistance of the first capillary tube 111 is small.
As shown by the broken arrows in FIG. 7, the high-pressure refrigerant gas flowing through the refrigerant pipe 23 flows out to the refrigerant pipe 32 side,
A part of the compression work performed by the compressor 4 will be discarded. That is, the supply pipe 41 and the first communication pipe 105
This means that when all of the high-pressure side shutoff valve 101 and the first low-pressure side shutoff valve 102 are opened, the same operation as the refrigerant return circuit in the conventional device is obtained. The first capillary tube 111 is set so that a high-pressure gas refrigerant for one horsepower flows when only the second compressor 4 is operated.

As described above, in the air conditioning systems of both the above embodiments, the four-stage capacity control of the variable capacity compressor is enabled by the four shut-off valves, and the piping for controlling the power control mechanism is also compared. I was able to reduce the target. In addition, since the supply pipe and the shutoff valve also function as the refrigerant return circuit, there is no need to provide a dedicated bypass pipe or a shutoff valve in the refrigerant return circuit, which further simplifies the equipment configuration and reduces costs. I realized it.

Next, a third embodiment of the present invention will be described.
FIG. 9 is a schematic configuration diagram of an air conditioning system according to the third embodiment. The same components as those in the configuration of FIG. 1 described in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The difference from FIG. 1 is that the supply pipe 41 has no capillary tube, and the bypass pipe 2 in which the normally closed refrigerant return shutoff valve 201 and the capillary tube 202 are interposed.
00 is provided between the refrigerant pipe 24 and the refrigerant pipe 32, and the rated output of the second compressor 4 'is 4 horsepower.

The bypass pipe 200 is connected to the refrigerant return shutoff valve 2.
By opening 01, a refrigerant return circuit is formed in which a part of the compressed high-pressure refrigerant gas is returned to the compressors 3 and 4 'via the low-pressure refrigerant circuits 32-35. In this embodiment, the flow resistance and the like of the capillary tube 202 are set so as to reduce the capacity by 0.5 horsepower by the refrigerant return circuit.

Hereinafter, a table of FIG. 10 showing the relationship between the capacity of the outdoor unit 1 and the ON / OFF states of the first and second compressors 3 and 4 'and the shut-off valves 45 to 48 and 201 will be described. The operation of the third embodiment will be described.

In the third embodiment, the power control mechanism of the first compressor 3 operates in the same manner as in the first embodiment in the case of 1 to 4 horsepower. When operating the refrigerant return circuit, the outdoor ECU 51 opens (turns on) the refrigerant return shutoff valve 201, and recirculates a part of the high-pressure refrigerant gas to the compressors 3 and 4 'through the suction-side refrigerant circuits 32-35. , 0.5 hp compression work is discarded. Activating the refrigerant return circuit wastes compression work by that amount, but reduces the work amount by half as compared with the related art.

The outdoor ECU 51 controls the operation of the first and second compressors 3 and 4 ′ and the power control mechanism 81 when the outdoor unit 1 generates a capacity of 0.5 to 8 hp.
The drive control of the refrigerant return circuit is performed as follows. That is, while operating only the first compressor 3, the first to third
The high pressure side shutoff valves 45 to 47 and the low pressure side shutoff valve 48 are drive-controlled in the same procedure as in the first embodiment and the drive control of the refrigerant return shutoff valve 201, so that 0 to 0.5 horsepower is achieved. .5 horsepower. While operating the first and second compressors 3, 4 'simultaneously, the first
If the third high pressure side shutoff valve 45 to 47, the low pressure side shutoff valve 48, and the refrigerant return shutoff valve 201 are drive-controlled, 4.5 to 8
Between horsepower you can get the ability every 0.5 horsepower.

In the air conditioning system according to the third embodiment, the operation control of the first and second compressors and the operation of the power control mechanism and the refrigerant return circuit make the capacity control 0.5 to 8 horsepower in the range of 0.5 to 8 hp. Since 16 levels can be switched for each horsepower and fine control can be performed, user comfort in the conditioned space is improved.

The description of the specific embodiment has been completed.
Aspects of the present invention are not limited to this embodiment.
For example, in the above-described embodiment, the present invention is applied to an air conditioning system including one variable capacity compressor and one fixed capacity compressor. Or may be applied to a machine having only a variable capacity compressor. Further, in the above embodiment, the power control mechanism of the four-stage control is provided in the twin rotor type constant speed compressor. However, the power control by the power control mechanism may be three or less stages or five or more stages. A machine having a compression mechanism of a triple rotor or more may be used. Further, regarding the structure of the power control mechanism, for example, a communication passage or a shutoff valve may be provided outside the compressor casing, or one end of a pressure supply pipe may be connected to a lower part of the compressor casing or a high pressure circuit side of an oil separator. Various configurations are conceivable, such as a configuration in which the refrigeration cycle is operated, and other specific configurations in the refrigeration cycle can be appropriately changed without departing from the spirit of the present invention.

[0049]

As described above in detail, according to the present invention, a variable capacity compressor whose capacity is controlled in three or more stages by a plurality of power control mechanisms is provided on the heat source side, and each of the power An air conditioner in which a control mechanism is driven by a high pressure supplied from a high pressure circuit and a low pressure supplied from inside a low pressure circuit, wherein the air conditioning apparatus is connected to the high pressure circuit to supply high pressure to each of the power control mechanisms. Since a single pressure supply pipe provided for supply and a plurality of shutoff valves interposed in the pressure supply pipe are provided, the number of pipes and the number of shutoff valves for the power control mechanism can be reduced. As a result, simplification of the device configuration and reduction of the manufacturing cost can be achieved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of an air conditioning system according to the present invention.

FIG. 2 is a half vertical sectional view showing the structure and operation of a power control mechanism.

FIG. 3 is a half vertical sectional view showing the structure and operation of a power control mechanism.

FIG. 4 is a schematic diagram showing an arrangement of a power control mechanism with respect to a compression mechanism.

FIG. 5 is a schematic diagram showing a refrigerant gas circuit and a control system for a power control mechanism in the first embodiment.

FIG. 6 is a table showing the relationship between the capacity of the outdoor unit and the ON / OFF states of the first and second compressors and each shutoff valve in the first embodiment.

FIG. 7 is a schematic diagram showing a refrigerant gas circuit and a control system for a power control mechanism in a second embodiment.

FIG. 8 is a table showing the relationship between the capacity of the outdoor unit and the ON / OFF states of the first and second compressors and each shutoff valve in the second embodiment.

FIG. 9 is a schematic configuration diagram showing a third embodiment of the air conditioning system according to the present invention.

FIG. 10 is a table showing the relationship between the capacity of an outdoor unit and the ON / OFF states of the first and second compressors and each shutoff valve in the third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outdoor unit 2 Indoor unit 3 1st compressor (variable capacity type compressor) 4 2nd compressor (constant capacity type compressor) 4 '2nd compressor (constant capacity type compressor) 23 Refrigerant piping (high pressure circuit) 32 Refrigerant pipe (low pressure circuit) 41 Refrigerant gas (pressure) supply pipe 42 First introduction pipe 43 Second introduction pipe 44 Third introduction pipe 45 First high pressure side shutoff valve 46 Second high pressure side shutoff valve 47 Third high pressure side shutoff Valve 48 Low pressure side cutoff valve 49 Capillary tube 51 Outdoor ECU 101 High pressure side cutoff valve 102 First low pressure side cutoff valve 103 Second low pressure side cutoff valve 104 Third low pressure side cutoff valve 106 First communication pipe 107 First communication pipe 111 1st capillary tube 112 2nd capillary tube 113 3rd capillary tube 201 Refrigerant return shutoff valve

Claims (5)

[Claims] 1. A variable capacity compressor whose capacity is controlled in three or more stages by a plurality of power control mechanisms on a heat source side, and each of the power control mechanisms is controlled by a high pressure pressure and a low pressure circuit supplied from a high pressure circuit. A single pressure supply pipe connected to the high-pressure circuit for supplying high-pressure pressure to each of the power control mechanisms, the air-conditioning apparatus being driven by the supplied low-pressure pressure; An air conditioner, comprising: a plurality of shut-off valves interposed in a pipe. 2. The pressure supply pipe is connected to the low-pressure circuit, branches off from the pressure supply pipe at different positions, and supplies a plurality of introduction pipes for supplying high-pressure pressure to each of the power control mechanisms. A high-pressure side shut-off valve that is provided corresponding to each of the introduction pipes and is interposed in the pressure supply pipe on the high-pressure circuit side from a branch position of each introduction pipe, and is closest to the low-pressure circuit among the introduction pipes. 2. The air conditioner according to claim 1, further comprising a low-pressure side shut-off valve provided on the pressure supply pipe on a side of the low-pressure circuit from a branch position of the introduction pipe. . 3. A variable capacity compressor whose capacity is controlled in three or more stages by a plurality of power control mechanisms on a heat source side, wherein each of the power control mechanisms includes a high pressure refrigerant gas flowing through a high pressure refrigerant circuit and a low pressure refrigerant gas. An air conditioner driven by a low-pressure refrigerant gas flowing in a refrigerant circuit, wherein a single refrigerant gas connected to the high-pressure refrigerant circuit and supplied to supply the high-pressure refrigerant gas to each of the power control mechanisms. An air conditioner comprising: a supply pipe; and a plurality of shutoff valves interposed in the refrigerant gas supply pipe. 4. The refrigerant gas supply pipe is connected to the low pressure refrigerant circuit so as to communicate the high pressure refrigerant circuit and the low pressure refrigerant circuit, and branches off from the refrigerant gas supply pipe at different positions. A plurality of inlet pipes for guiding the refrigerant gas to each power control mechanism, and a plurality of inlet pipes are provided corresponding to each of the inlet pipes, and the refrigerant gas supply pipe is interposed on the high-pressure refrigerant circuit side from a branch position of each inlet pipe. A high pressure side shutoff valve, which is provided corresponding to the one of the introduction pipes closest to the low pressure refrigerant circuit, and is interposed in the refrigerant gas supply pipe on the low pressure refrigerant circuit side from a branch position of the introduction pipe. The air conditioner according to claim 3, further comprising a low-pressure side shutoff valve. 5. A high pressure side shut-off valve interposed in the refrigerant gas supply pipe, and a number corresponding to each of the power control mechanisms are provided, and the high pressure side cutoff valves are connected to the refrigerant gas supply pipe and the high pressure refrigerant circuit and the low pressure A communication pipe that communicates with the refrigerant circuit; an introduction pipe that branches one by one from each of the communication pipes and guides the refrigerant gas to a corresponding power control mechanism; The air conditioner according to claim 3, further comprising a low-pressure side shutoff valve interposed in each communication pipe.