JPS61110833A - Heat recovery type air conditioner - Google Patents

Abstract

PURPOSE:To contrive to operate the compressor related to the utilizing coil side under efficient condition by a method wherein a compressor mechanism is divided into two systems, the intaking side of one side system is connected to a gas pipe side and the intaking side of the other side system is connected to an indoor unit. CONSTITUTION:A compressor mechanism 1 is provided in parallel with two compressors 1A, 1B of which each discharging side is connected collectively to the high pressure side port of an open/close valve 3D, and the intaking side of the one side compressor 1A is connected to the intake side port of an open/ close valve 3S. An open/close valve 16 is interposed at intermediate position between the compressor 1A and 1B. In above structure, a heat source side soil 2 is acted as an evaporator, further, the open/close valve 3S is opened and the open/close valve 3D is closed according to the requirement for an operational control. In case that the heat source side coil 2 is acted as the evaporator, the open/close valve 16 is closed, then the coolant sucking from the heat source side coil 2 and the coolant sucking from the utilizing side coil 9 are respectively performed partially by the compressor 1A and the compressor 1B.

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention connects a plurality of indoor units to one outdoor unit so that cooling or heating operation can be selected individually, so that the outdoor unit can accurately control the capacity corresponding to the total load. (Conventional technique #I) A plurality of indoor units are connected in parallel to one outdoor unit, and at least one indoor unit is operated for cooling. An air conditioner capable of so-called heat recovery, in which at least one remaining indoor unit can be operated for heating when the room is in use, and the heat radiated for cooling can be directly used as a heat source for heating during this operation, is disclosed in Japanese Patent Application Laid-Open No. 55. This is known from Japanese Patent No. 12372. This known example is an outdoor unit (outdoor unit) (as shown schematically in FIG. 7).
Al includes a compressor 11.1, a heat source side coil (21, a discharge gas on-off valve (3D), an intake gas on-off valve (3s),
Equipped with branch main pipe (51), high pressure gas side main pipe (61), low pressure gas side main pipe (7), and heating expansion valve (goods), each indoor unit (IA), (1A), (1B), ( Engineering C)
The high-pressure gas side branch pipes (111, on-off valves (14A) to (140) each have a cooling expansion valve (8), a usage-side coil (9), and on-off valves (13A) to (13o), respectively. In the above air conditioner, the indoor units (IA) and (IB) that are to be cooled have on-off valves (14A), (
14B) and, on the other hand, open the on-off valve (130) in the indoor unit (work 0) that attempts to perform heating, but on the other hand, in the outdoor unit (AI) Depending on the operating condition, if the cooling load is large, the heat source side coil (21) must act as a condenser, so open the on-off valve (3D); conversely, if the heating load is large, the heat source side Since the coil has to act as an evaporator, it is necessary to open the on-off valve (3S). (Problem to be solved by the invention) An air conditioner with such a structure has a part in the cooling operation and the rest in the cooling operation. When performing heat recovery operation by operating heating operation, there are states in which the heating load and cooling load are balanced, states in which the heating load is greater, and states in which the cooling load is greater, especially in winter. When the heating load is larger, the heat source side coil (2) naturally acts as an evaporator, but in that case, since the outside air temperature is low, it is necessary to lower the evaporation temperature of the heat source side coil (21). As a result, frost rapidly grows on the user-side coil (9) of the indoor unit running the cooling operation, which is a great inconvenience as it has to be defrosted repeatedly. This had the disadvantage of increasing the frequency of shutdowns, resulting in severe fluctuations in the temperature of the room temperature, and a poor coefficient of performance.In this way, conventional heat recovery type air conditioners had the disadvantage of frequent formation of frost that interfered with cooling operation. The present invention has been made in view of a certain point, and only when the heat source side coil is performing heat absorption operation in the compression mechanism in the outdoor unit, the heat source side coil for low temperature evaporation and the heat source side coil for high temperature evaporation are connected. By making it possible to operate in two systems, separated from the user-side filter, frost formation is eliminated, the coefficient of performance is improved, and the temperature is stable and smooth, making it possible to perform two heat recovery operations with cooling operation. The purpose of the present invention is to fully adapt to the demands of the demand side. (Means for solving the problem) Therefore, the present invention provides a heat source side that can be switched to a compression mechanism +1+, a condenser or an evaporator. The outdoor unit has an AJ, a cooling pressure reducer (81, and a user-side coil (91), and can be individually switched to cooling operation or heating operation. In a heat recovery air conditioner consisting of a plurality of indoor units (IA) and (IB) connected in parallel to each other, the compression mechanism (1) is divided into two systems. A part of each indoor unit (IA) performs cooling operation, and the remaining part performs two heating operations, and the heat source side coil (21) performs two heating operations. During air conditioning operation that functions as an evaporator, the suction side of one system in the compression mechanism Fll is separated into the outdoor unit (AJ gas side pipe), and the suction side of the other system is separated into the indoor unit during cooling operation. (In other air conditioning operations, the suction sides of both systems are connected to the outdoor unit.) (A switching device α6j that is commonly connected to the AI suction line or to the indoor unit during cooling operation is attached to the compression mechanism tl+. It is structured as follows. Further, the present invention provides that the compression mechanism (1) has a switching port at one end of the suction side 2 of one system and the heat source side coil +21, each compressor (1A) of the compression mechanism (1), (1A), (
1B), the high pressure side port is commonly connected to the low pressure side port of the first switching valve system 131, and the suction side of the other system is connected to the low pressure side port of each indoor unit (IA). , (1A) and (1B) are connected to the branch-connected low-pressure gas side main pipe (71), and
It is also a preferred embodiment that the switching device α mark is constituted by an on-off valve αG that is openable and closable in the middle of the piping that connects the suction sides of both systems in the compression mechanism (1). be. (Function) Therefore, in the present invention, when the heating load is larger than the cooling load and the heat source side coil (21 serves as an evaporator and performs endothermic operation),
The compression mechanism (the compressor (IA) whose mouth is connected to the heat source side coil (21) to operate for low-temperature evaporation, and the user-side coil (91) that acts as an evaporator to operate for high-temperature evaporation By operating the compressor (IB) separately from the compressor (IB), it is possible to perform compression operation adapted to the respective conditions, reducing the required power and improving the overall coefficient of performance. It is possible to suppress frost formation on the coil (91) as much as possible. (Example) An example will be described in detail below based on the attached drawings. In Fig. 1 (AJ is an outdoor unit) (IA), (IB
). (IC) is an indoor unit, and these indoor units (IA
], (IB), (Eng.
7). The outdoor unit (A) is a compression mechanism capable of capacity control, such as a capacity control device (19A) such as a frequency converter, (19
Two compressors (1A), (1A), (1
B) and the heat source side coil

[2] and the refrigerant flow control device (4
) For example, the refrigerant circuit is equipped with an electric refrigerant flow control valve (41), a first valve switching device (31, a switching device αa, for example, an on-off valve αe, and a liquid receiver 4), and an outdoor fan (281
It is available with attached. The refrigerant flow control valve (41 (hereinafter abbreviated as control valve +41) is interposed in the branch main pipe (51), and has an electric device such as a pulse motor or an electromagnetic plunger as a driving element to receive input electricity. It is an expansion valve whose opening degree can be adjusted according to the amount, and the valve opening degree can be easily adjusted by electrical control.The first switching valve device [31 is two on-off valves (3]: L),
(3S) is an element, and has a high pressure side port, a low pressure side port, and a switching port for switching and communicating with both ports, and an on-off valve (3S) on the discharge side of the compression mechanism (1).
) is formed so that it can be alternately switched and communicated with the heat source side coil (21) by opening the heat source side coil (21). (1B) in parallel, and the discharge side is connected to the high pressure side port of the on-off valve (3D) and the high pressure gas side main pipe (61), while the suction of one compressor (IA) The side is the on-off valve (3S)
The suction side of the other compressor (IB) is connected to the suction side port of the other compressor (IB). Connect them with piping and install a switching device α mark in the middle of this piping.
Specifically, an on-off valve α0 is provided. Next, the indoor units (IA) to (Engine C) all have a cooling pressure reducer +81 and a user side coil (9) connected in series, and a check valve - to the pressure reducer 18. It has a circuit configuration with parallel reading, in which the inflow sides of the cooling pressure reducers (81) are respectively connected to the branch main pipe (5), and one end of the utilization side fill (9) which becomes the outlet during cooling operation, Open/close valve (1
3A) (130) are interposed respectively in the high pressure gas side branch pipes [
+11 connects to the high pressure gas side main pipe (6), and
On-off valves (14A) to (14) are connected to the low-pressure gas side main pipe (7) by t-pressure gas side branches!F (+21), and two types of on-off valves (13A) to (13 (1 and on-off valves (14A) to (140) are combined to form a second switching valve device (IOA) to (100). Note that Q51 is a fan for the user side coil (91). The air conditioner with the above circuit configuration is an indoor unit (I
If you want to perform cooling operation in A) ~ (step 0), open the on-off valves (14A) ~ (140), and open the on-off valves (13A) ~
Open (130) and open/close valves (14A) to (140)
It is intended to close the On the other hand, in the outdoor unit (A), depending on whether the total load on the indoor side is a cooling load or a heating load, the heat source side coil +21 needs to act as a condenser or an evaporator, and in the former case, an on-off valve is required. (3D) is opened, on-off valve (3D) is opened.
S), and in the latter case, conversely, close the on-off valve (
3S) and close the on-off valve (3D). In addition, the capacity control of compressor +11 is performed by each capacity control device (
19A) and (19B), while the control valve (4) controls the amount of refrigerant flowing into the heat source side coil (21).
These devices (19A) and (19B), and a switching controller (211) that switches the valve of the first switching valve device (31), and further, The on-off controller (a) that opens and closes the on-off valve Q6) is formed into the control device αη.As mentioned above, in the indoor units (IA) to (work 0), the air conditioner pz is optionally switched to the heating mode. If switching is possible and simultaneous operation of cooling and heating is performed, the condensing capacity or evaporation capacity corresponding to the difference between the cooling load and the heating load is carried by the heat source side coil (2) outside the room. Heat recovery operation using heat efficiently becomes possible. What is the operation mode of the heat source side coil +21 in this case? The relationship between the cooling load and the heating load, the capacity of the compression mechanism +11, the opening degree of the control valve +41, and the opening/closing valve. (3D), (3S)・α
FIG. 3 shows the relationship between the opening and closing states of 0 and 0, and in FIG. There is. As is clear from Fig. 3, if you want to make the heat source side coil (2) act as a condenser and control its capacity, the on-off valve (
Open the on-off valve (3D), close the on-off valve (3S), and open the control valve (4).
].On the contrary, if you want to operate as an evaporator and control the capacity, open the on-off valve (3S), close the on-off valve (3D), and adjust the opening of the control valve (41). In addition, if you want the heat source side coil +21E to act as a condenser, open the on-off valve αe and compressor (1A), (1
A) and (1B) are operated in parallel, and if you wish to operate them conversely as an evaporator, close the on-off valve αe and connect the compressor (IA
) draws refrigerant from the heat source side coil (2) to the compressor (1
A) and (1B) are configured to share the refrigerant suction from the user side coil (91).Furthermore, the capacity control of the compressors (1A), (1A), and (1B) is also performed. By doing so, it is possible to perform refrigeration operation without excess or deficiency commensurate with the air conditioning load.Although not shown in Figure 3, the indoor unit (I
When all of A) to (IB) are operating for cooling or heating, the on-off valve OG is kept open. The control command means α& for giving control commands to the control device αη that meet the purpose of the refrigeration operation described above will be explained below based on the drawings. The control command means 081 includes a high pressure and force detection circuit, a low pressure and force detection circuit, a superheat degree detection circuit (to), a secondary capacity determination circuit, a switching valve control circuit (), a first switching valve control circuit ( 3
z and on/off valve control circuit @ 8 circuits of 4. The functions of each circuit are explained below. ◎ High pressure and force detection circuit. Pressure sensor that detects the pressure of the high pressure gas side main pipe f6i1 (
SI) as a detection end, and if the high pressure force detected by the sensor (S, If the pressure is too high, a high pressure shortage signal will be generated, and if the pressure is too high, a high pressure excess signal will be generated.Instead of the pressure sensor (Si), a temperature sensor that can detect the discharge side saturation temperature and convert it into pressure may be used. Force detection circuit. Pressure sensor (S) that detects the pressure of the low pressure gas side main pipe (71
J as a detection end, and if the low pressure force detected by the sensor (S,) is within the range of the set conditions, that is, within the pressure band, it is a low pressure appropriate signal, if it is low, it is a low pressure insufficient signal, and if it is high, it is a low pressure excessive signal. This pressure sensor (S
i) may be replaced with a temperature sensor similar to the pressure sensor (Sθ). ◎ Superheat degree detection circuit (241 degrees) It has a sensor (sa) and (sJ) for detecting the refrigerant temperature, and the temperature difference between these two sensors (sJ) and (Sa) is the degree of superheat.The sensor (Sa) detects the pressure. This may be electrically converted into a temperature signal. ◎ Primary ability judgment circuit. The output signal is obtained by receiving the divided output signals of the high pressure and force detection circuit and the low pressure and force detection circuit, and by combining them. It is a logic circuit that distinguishes 9 types of signals and converts them into 5 types of output signals.The compressor (1A)
(1B) That is, a capacity increase signal for increasing the capacity of the compressor whose suction side is connected to the low-pressure gas side main pipe (7) is issued to the capacity control device (19B), and a high-pressure excessive signal and a low-pressure insufficient signal are generated. AND the compression 1 (1A), (1B)
The device (19B) sends a capacity reduction signal to reduce the capacity of the device (19B).
emanates from. Also, each AND of the high pressure shortage signal and the low pressure appropriate signal, the high pressure shortage signal and the low pressure shortage signal, and the high pressure appropriate signal and the low pressure shortage signal
QR is taken to issue a cold/warm mode signal, and the O'R of the appropriate high pressure signal and excessive low pressure signal, excessive high pressure signal and excessive low pressure signal, and excessive high pressure signal and appropriate low pressure signal is taken to set the cool/warm mode. emit a signal. Furthermore, a hold signal is generated by ANDing the high voltage appropriate signal and the low voltage appropriate signal. ◎Second ability judgment circuit□□□. It receives the output signals of the high pressure and force detection circuit (231), the low pressure and force detection circuit (231), and the primary ability determination circuit (to) and outputs the following signals. (1') Primary ability determination Output group under the condition that circuit 4 is cold and generates a warm mode signal, and when high pressure power detection circuit ■ generates a high pressure shortage signal, the low pressure side port of the compressor (IA) 1, that is, the on-off valve (3S) A capacity increase signal to increase the capacity of the compressor connected to the suction side is sent to the capacity control device (19A), and when a high pressure excessive signal is sent to the high pressure and force detection circuit, the compressor (IA) is A capacity reduction signal to decrease the capacity is issued to the device (19A). Also, when the low pressure and force detection circuit is connected and a low pressure excessive signal is issued, a capacity increase signal is issued to increase the capacity of the compressors (1A) and (1B). is sent to the capacity control device (19B), and conversely, when a low pressure excessive signal is being generated, the compressor (1A), (
a capacity reduction signal to reduce the capacity of said device (1B);
9B). Further, a hold signal is generated by ANDing the high pressure appropriate signal and the low pressure appropriate signal [231] to both pressure detection circuits. [q 1st performance judgment @ Roko is cold] Output group under the condition that the warm mode signal is issued, high pressure insufficient signal in the high pressure and force detection circuit and low pressure appropriate signal or low pressure excessive signal in the low pressure and force detection circuit The compressor (
1A), (1A), (1B) capacity? A capacity increase signal to increase the capacity is issued to the capacity control devices (19A) and (19B), and an AND between a high voltage excessive statement and a low pressure signal or a low pressure insufficient signal, and an AN between a high voltage appropriate signal and a low pressure insufficient signal are issued.
D sends a capacity reduction signal to both the devices (19A) to reduce the capacities of the compressors (1A), (1A), and (1B).
. (19B). On the other hand, AND of the low pressure excessive signal and the high pressure proper signal or the high pressure excessive signal, and the AND of the low pressure proper signal and the high pressure excessive signal
A signal for increasing the opening of the control valve (41) is issued to the control valve control circuit, and a low pressure shortage signal and a high pressure shortage signal or a high pressure appropriate signal are ANDed, and a low pressure appropriate signal and a high pressure shortage signal are generated. Control valve +41 by AND with
A valve opening signal that decreases the opening of the circuit [sent to the circuit board]. Further, a hold signal is generated by AND- of the high voltage appropriate signal and the low voltage appropriate signal. ◎ A signal smaller than a predetermined superheat degree so that the signal of the superheat degree detection circuit example becomes a low pressure appropriate signal by the control valve control circuit (311゜the primary capacity determination circuit) emitting a cold/warm mode signal. A valve opening control signal is issued to the valve opening control device (20) to decrease the valve opening of the control valve (41) and to increase the valve opening by a large signal. is a stepless control over the control valve (41, which is the heat source side coil that acts as an evaporator + 21)!i - corresponds to control to maintain the degree of superheat constant T. On the other hand, as mentioned above, the primary capacity determination circuit (251 is cold〉
It receives a valve opening increase signal or a valve opening decrease signal when two warm mode signals are issued, and sends this to the valve opening control device. This is step control and corresponds to capacity control that attempts to adjust the heat radiation capacity of the heat source side fill (21) that acts as a condenser to the difference between the cooling load and the heating load. ◎ First switching control circuit Gz. The capability determination circuitry opens the on-off valve (3S) by issuing a cold/warm mode signal, and also opens the on-off valve (3S).
D] is issued to the switching controller (211), and on the other hand, the on-off valve (3) is closed by issuing a cold/warm mode signal.
The switching controller issues a signal to open D) and close the on-off valve (3S). ◎ Open/close valve control circuit. By issuing a cold/warm mode signal, the primary capacity determination circuit issues a signal to the on/off valve controller (to) to close the on/off valve Q61i, and on the other hand, by issuing a cold>warm mode signal, the on/off valve Q61i is closed. A signal to open αeB is sent to the on-off valve controller. The contents of the control command means α& have been explained above.Next, the outline of the operating mode of the air conditioner shown in FIG. 1 will be further explained with reference to FIGS. 2 to 6. On-off valve (3S) '2 open, on-off valve (3D) and on-off valve 0
61 and assumes that the heating cycle is the basic one and that the heating load and the cooling load are balanced, set this as the initial condition and start operation. Note that under this initial condition, the compression The compressor (IA) is stopped, the compressors (1A) and (1B) are driven at the medium capacity of the initial operation, and the control valve +41 is fully closed (waiting for an opening command). After the start of operation, at 1-minute intervals, etc. This state is maintained for a predetermined period of time, and the check signal issued here causes the primary capability determination circuit (to) to perform a capability determination. By detecting the pressure in the low-pressure force detection circuit, nine types of signals obtained by the combination are discriminated, and the compressor (1A),
A capacity increase signal (EI), a capacity decrease signal (K), a hold signal (K,) to increase the capacity of (1B), a cold signal to increase the capacity of the compression mechanism 111 because the heating load is larger. Warm mode signal (X,), when the cooling load is larger, the compression mechanism (moon capacity control and heat source side coil (21) capacity control is desired. Cool>Warm mode signal CI [ii)
Selectively emit and close. When the hold signal (IJ) is being issued, the current operation is continued and the capacity judgment is made again after one minute has passed.On the other hand, when the capacity increase signal (El) is being issued,
Compressor (1A), (1
Increase the capacity of B) by 1 step, Q, and perform ability judgment 2 again after 1 minute has passed. On the other hand, when the capacity reduction signal UC, ) is being issued, the capacity control device (19B) reduces the compressor (IB) by 1
Decrease the capacity by the step (■), and after 1 minute has passed, perform ability judgment 2 again. Furthermore, when the cold/warm mode signal (E4) is being issued, the control valve control circuit (3I) is switched to the constant superheat control side and the capacity is judged by the second capacity judgment circuit Th f301. When the cold>warm mode signal (E,) is issued, the control valve control circuit (switches to the opening step control side for 3υ and the first switching valve control circuit @
2, a command to open the on-off valve (3D) and close the on-off valve (3S), a command to open the on-off valve Q61 to the on-off valve control circuit (33), and a command to open the on-off valve Q61 to the on-off valve control circuit (33), and a command to open the on-off valve Q61 to the on-off valve control circuit (33). Therefore, the operation based on the former cold/warm mode signal (E4) is performed.
In this case, the nine types of signals obtained by the combination of pressure detection in the high pressure and pressure detection circuit (1) and pressure detection in the low pressure and pressure detection circuit (2) increase the capacity of the compressor (IA). , and a signal (θ,) that decreases the capacity of the compressors (1A) and (1B), a signal (e,) that increases the capacity of the compressor (IA), and a signal that increases the capacity of both compressors (LA) and (1B). (eΩ, signal (e,) that reduces the capacity of only compressors (1A) and (1B), both compressors (1A),
A signal (e6) that increases the capacity of only the compressors (1A), (1B), both compressors (1A), (1A), (
Signal (e?) to reduce capacity of 1B), compressor (IA)
A signal (,,) that causes the capacity of only the compressor (IA) to decrease and a signal (e,) that causes the capacity of the compressors (1A) and (1B) to increase are selected and emitted. Compatible compressor (IA). (1A) and (1B) capacity control is performed. Then, check whether the capacity of the compressor (IA) is zero, that is, the cooling load and the heating load are balanced, and the compressor (IA) stops.■ Check the pressure again at θ every minute until the compressor (IA) stops.■ When the control valve (41) is fully closed, the capacity judgment by the original primary capacity judgment circuit is repeated. On the other hand, the operation based on the latter cooling/warming mode signal (Ka) is performed.
In the case of , nine types of signals are obtained by the combination of the pressure detection (1) of the high pressure and force detection circuit and the pressure detection of the low pressure and force detection circuit, that is, the opening degree 2 of the control valve (4). A signal (θ′,) that decreases the opening degree step by step,
Similarly, a signal (,',) that gradually decreases the opening of the control valve (41) and increases the capacity of both compressors (1A), (1A), (1B), both compressors (1A), ( 1A), (
1B), a signal (e'J) that increases the capacity of both compressors (I
A), reducing the capacity of (1A) and (1B), and
A signal (e') that gradually decreases the valve opening degree of the control valve (4).
t), control valve (opening degree of 41 and both compressors (1A), (
1A), (1B) are kept at their current capacity (bold), signal (e',), both compressors (1A), (1A), (
1B), and a signal (e'l) that increases the valve opening degree of control valve +41 in stages, both compressors (LA),
Signal (e') that reduces the capacitance of (1A) and (1B)
), a signal ("II") that reduces the capacity of both compressors (1A), (1A), (1B) and increases the valve opening degree of control valve (41) in stages ("II), A signal (e'o) that increases the opening stepwise is selected and emitted, and the compressors (1A), (1A), (1
To perform the capacity control of B) and the valve opening control of control valve +41) to (B). Then check whether the opening degree of the control valve (41) is fully closed.
Then, the pressure is detected again by θ every minute until the cooling load and heating load are balanced. When the compressor (IA) is fully closed, the compressor (IA) is stopped and the original primary capacity is restored. The ability judgment by the judgment circuit is repeated. In addition, in the 70-diagram, rpa J is high pressure force, rpeJ
indicates a low pressure, and ``old age'', ``high pressure'', and ``high pressure'' indicate a high pressure insufficient signal, a high pressure appropriate signal, and a high pressure excessive signal, respectively. Further, low/low, low proper/low excessive indicate a low pressure insufficient signal, a low pressure appropriate signal, and a low pressure excessive signal, respectively. As is clear from the above explanation, depending on the difference between the cooling load and the heating load, the capacity control of the compressor (1) and the control valve +
41 opening degree control, the first valve switching device (31 switching control, and the opening/closing control of the on-off valve Q61), highly effective heat recovery operation is possible. In particular, the utilization side fill (9) When at least a part and the heat source side coil (21) are used as an evaporator at the same time, the on-off valve αG is closed and the compressor (1A), ( 1B) at a suction pressure of, for example, 5,000 yen, as a separate system, the indoor compressors (1A) and (1B) can be used under advantageous conditions, and the frosting of the user-side coil (9) can be reduced. In addition, it is expected that the capacity of the compressors (1A) and (1B) will be reduced and the coefficient of performance will be improved. (Effects of the Invention) The present invention divides the compression mechanism fl+ in a heat recovery air conditioner into two systems. When some of the indoor units (IA) and (1B) are in cooling operation and the rest are in heating operation, and the heat source side coil (2) is in air conditioning operation where it acts as an evaporator, one of the compression mechanisms +i+ Fill the system on the heat source side (2)
The other system is used for refrigerant suction from the coil f9+
Since the compressor is used separately for suction of refrigerant from It is possible to expect a reduction in machine capacity and an improvement in the coefficient of performance.

[Brief explanation of the drawing]

FIG. 1 is a refrigeration circuit diagram according to an embodiment of the present invention, FIG. 2 is an electric circuit block diagram, FIG. 3 is an explanatory diagram of the operating state of the apparatus shown in FIG. 1, and FIGS. 4 to 6 are FIG. 1 is a flow diagram showing the operation control mode of the apparatus shown in FIG. 1, and FIG. 7 is a refrigeration circuit diagram of a conventional air conditioner. Hl... Compression mechanism, (1A) (1A), (1B
)...Compressor. (2) Heat source side coil, (3)... First switching valve device. (41... Refrigerant flow rate control device. (71... Low pressure gas side main pipe, (81... Air conditioning pressure reducer. (91... Utilization side coil, θ61... Switching device. (Al... Outdoor unit, (A) (IB)... Indoor unit.

Claims (1)

[Claims] 1. A compression mechanism (1), a heat source side coil (2) that can act as a condenser or an evaporator, and a refrigerant flow rate control device (
4) and an outdoor unit (A) having a cooling pressure reducer (8).
) and a user-side coil (9), a plurality of indoor units (I_A) connected in parallel to the outdoor unit (A) so as to be individually switchable to cooling operation or heating operation;
In a heat recovery air conditioner consisting of (I ＿B),
The compression mechanism (1) is composed of a plurality of compressors (1A) and (1B) divided into two systems, while a part of each indoor unit (I_A) and (I_B) performs cooling operation. ,
The remainder performs heating operation, and the heat source side coil (2)
During air conditioning operation in which the compressor functions as an evaporator, the suction side of one system in the compression mechanism (1) is connected to the gas side pipe of the outdoor unit (A), and the suction side of the other system is connected to the indoor unit during cooling operation. For other air conditioning operations, connect the suction sides of both systems to the outdoor unit (A
The switching device (16), which is commonly connected to the suction line of the compressor ( ) or the indoor unit in cooling operation, is connected to the
A heat recovery type air conditioner characterized by being attached to 1). 2. Multiple compressors divided into 2 systems (1A), (1
A compression mechanism (1) consisting of a plurality of compressors (1A), (B) has a switching port at one end of the heat source side coil (2), and
The suction side of one system is connected to the low pressure side port of the first switching valve device (3), which has a high pressure side port commonly connected to each discharge side of 1B), and the suction side of the other system The suction side of each indoor unit (I ＿A), (I ＿B)
is connected to the branch-connected low-pressure gas side main pipe (7), and furthermore, a switching device (16) is openably and closably interposed in the middle of the pipe connecting the suction sides of both systems in the compression mechanism (1). A heat recovery type air conditioner according to claim 1, wherein the heat recovery type air conditioner is formed of an on-off valve (16).