JPH0743180B2 - Heat pump type air conditioner - Google Patents

Description

The present invention relates to a heat pump type air conditioner, and more particularly to a measure for improving the controllability of the opening of an electric expansion valve when it is arranged in a refrigerant circulation system.

(Prior Art) Conventionally, in an air conditioner, for example, JP-A-61-963
As disclosed in JP-A-76, an electric expansion valve is arranged in a refrigerant circulation system, and room temperature detection means for detecting an indoor temperature (room temperature) is provided in the vicinity of a load side heat exchanger of the refrigerant circulation system to provide air conditioning. At the time of operation, the target opening value of the electric expansion valve is calculated according to the deviation between the actual room temperature detected by the room temperature detecting means and the room temperature target value, and the opening of the electric expansion valve is changed so as to reach this target opening value. It is known whether the comfortable air conditioning of the room is performed by controlling the air conditioning capacity to correspond to the air conditioning load by controlling.

(Problems to be solved by the invention) By the way, as a type of air conditioner, a four-way switching valve is provided in a refrigerant circulation system so that switching between a cooling operation cycle and a heating operation cycle is possible, and an indoor cooling operation is appropriately performed. And there is a heat pump type that can perform heating operation. In this type of air conditioner, when the heat source side heat exchanger of the refrigerant circulation system is frosted during the heating operation or the amount of lubricating oil in the compressor is insufficient, the refrigerant circulation system is switched to the cooling operation cycle. At the same time, the rotation of the blower fan of the heat source side heat exchanger may be stopped to perform special operations such as defrosting operation of the heat exchanger and oil recovery operation to the compressor.

However, when the heating operation is stopped and the special operation different from the heating operation is performed during the heating operation as described above, the refrigerant circulation system is switched to the cooling operation cycle during the special operation. The room temperature detecting means in the vicinity of the (evaporator) is cooled by the cold air that has been heat-exchanged by the load side heat exchanger, and is at a temperature lower than room temperature. As a result, even when the indoor heating operation is started after that, the room temperature detection means erroneously detects the room temperature at a temperature lower than the actual value, and the opening control of the electric expansion valve during the heating operation becomes an appropriate value. There is a drawback that it becomes too large in comparison. In particular, when shifting from the special operation to the heating operation, in order to increase the heating capacity at the beginning of the heating operation, for example, the initial opening value of the electric expansion valve is set according to the deviation between the room temperature and the room temperature target value. In this case, since the opening value of the electric expansion valve becomes a larger value, even if the temperature of the room temperature detecting means gradually rises thereafter, the electric expansion valve is gradually reduced accordingly. Even if the opening value is controlled to be gradually decreased, it takes a long time to converge to the room temperature target value, the control system becomes unstable, and the controllability deteriorates.

The present invention has been made in view of these points, and an object thereof is to perform heating operation and special operation such as defrosting operation as described above, and to end the special operation and perform heating operation. In addition, by prohibiting the opening control of the electric expansion valve in the heating operation until the temperature of the room temperature detecting means is not lowered due to the cooling cycle in the special operation and becomes almost equal to the room temperature value, The purpose of this is to prevent an increase in valve opening due to low temperature side erroneous detection, improve convergence to a room temperature target value, improve control stability, and improve indoor comfort.

(Means for Solving Problems) In order to achieve the above object, the solving means of the present invention is
As shown in the figure, the compressor (1, 2), the four-way switching valve (3),
It is premised on a heat pump type air conditioner including a refrigerant circulation system (14) in which a heat source side heat exchanger (4), an electric expansion valve (11) and a load side heat exchanger (10) are formed in a closed circuit. A room temperature detecting means (TH ₁ ) arranged near the load side heat exchanger (10) for detecting room temperature and the refrigerant circulation system (1
4) as a heating operation cycle and the electric expansion valve (11)
Heating operation control means (50) for variably controlling the opening degree of the room temperature detection means (TH ₁ ) according to the deviation between the room temperature and the room temperature target value.
And a refrigerant circulation system (1) at a special time different from the heating operation by the heating operation control means (50).
4) is the cooling operation cycle and the load side heat exchanger (1
0) Special operation control means (51) for stopping the blower fan (10a). Furthermore, the special operation control means (5
When the end detection means (52) for detecting the end of the special operation by 1) and the output of the end detection means (52) are received, the temperature of the room temperature detection means (TH ₁ ) is changed after the end of the special operation. The heating operation control means (5
The control prohibiting means (53) for prohibiting the variable control of the opening degree of the electric expansion valve (11) by (0) is provided.

(Operation) With the above configuration, in the present invention, during the heating operation, the opening degree of the electric expansion valve (11) is controlled by the heating operation control means (50), and the deviation between the room temperature and the room temperature target value is large. Since the opening degree is sometimes adjusted to a large opening and the heating capacity is increased, the degree of increase in room temperature is increased and the room temperature target value is quickly converged. When the deviation is a small value, it is adjusted to a small opening value and the heating capacity is reduced, so that the heating capacity is not excessive and the room temperature converges to the target value satisfactorily.

On the other hand, during special operations such as defrosting operation and oil recovery operation, which are different from the above heating operation, the special operation control means (51) switches the refrigerant circulation system (14) to the cooling cycle, and the load side heat exchanger. The blower fan (10a) of (10) is stop-controlled to defrost the load-side heat exchanger (10) and recover oil to the compressors (1, 2). At this time, since the refrigerant circulation system (14) is switched to the cooling operation cycle, the room temperature detection means (T) near the load side heat exchanger (evaporator) (10)
H ₁ ) is cooled by cold air and becomes lower than room temperature.

However, when the special operation is finished and the heating operation is started thereafter, the opening control of the electric expansion valve (11) by the heating operation control means (50) is prohibited by the control prohibiting means (53). , This prohibition control is based on the above room temperature detection means (T
The temperature of H ₁ ) is maintained for a set time equal to room temperature. As a result, since the room temperature detecting means (TH ₁ ) accurately detects the room temperature when the set time has elapsed, the opening degree of the electric expansion valve (11) is determined based on the opening degree detection value. Controlled by (50), the opening value of the electric expansion valve (11) becomes an appropriate value that corresponds well to room temperature, and the convergence of room temperature to the room temperature target value will be performed well in a short time. .

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings starting from FIG.

FIG. 2 shows an embodiment in which the present invention is applied to a multi-type air conditioner, where (A) is an outdoor unit and (B) to (F) are five indoor units having the same internal configuration, Inside the outdoor unit (A), there are a first compressor (1) and a second compressor (2) connected in parallel with each other, a four-way switching valve (3), and an outdoor blower fan (4a). An outdoor heat exchanger (4) as a heat source side heat exchanger and an expansion valve (5) are provided, and each of the devices (1) to (5) is a refrigerant pipe (6).
Is connected so that the refrigerant can flow. Further, each of the indoor units (B) to (F) includes an indoor heat exchanger (10) as a load side heat exchanger having an indoor blower fan (10a),
An indoor electric expansion valve (11) for adjusting the air conditioning capacity is provided, and the devices (10) and (11) are connected to each other through a refrigerant pipe (12) so that the refrigerant can flow.

The five indoor units (B) to (F) are connected in parallel to each other by refrigerant pipes (13) ... And are connected to the outdoor unit (A) so that the refrigerant can circulate. 14) is formed, and during the cooling operation, the four-way switching valve (3) is switched as shown by the broken line in the drawing to circulate the refrigerant as shown by the broken line arrow in the drawing, whereby each indoor heat exchanger (10) is
The indoor heat exchanger (4) repeatedly radiates the amount of heat absorbed from the room to the outside air to cool each room, while switching the four-way selector valve (3) as shown by the solid line during heating operation. By circulating the refrigerant as shown by the solid line arrow in the figure, heat exchange is performed in the opposite manner to heat the room.

An inverter (15) is connected to the first compressor (1), and its capacity is increased or decreased by adjusting the operating frequency of the compressor (1), and the second compressor (2) is also adjusted. Has an unloading mechanism (2a), and when the pilot solenoid valve (17) in the pilot pressure introducing passage (16) of the unloading mechanism (2a) is closed, the high pressure acts on the second compressor (2). While the pilot solenoid valve (17) is opened, the low pressure acts to unload the capacity of the second compressor (2) to 50% while the capacity of is fully loaded.

Further, in FIG. 2, (20) is a pressure equalizing hot gas bypass circuit that connects the refrigerant pipes (6) and (6) (the discharge pipe and the suction pipe) before and after the four-way switching valve (3), The bypass circuit (20) is provided with a hot gas solenoid valve (21) which is opened when the load is low in the cooling operation state, the defrosting operation of the outdoor heat exchanger (4), and the like.

Further, (22) is a heating overload bypass circuit connected to the refrigerant pipe (6) serving as a discharge pipe during the heating operation, and the bypass circuit (22) includes an auxiliary capacitor (23).
Further, a high pressure control valve (24) which is opened when the pressure of the refrigerant is high is interposed, and the refrigerant from the compressors (1) and (2) is exchanged with the heat of each room through the bypass circuit (22) at the time of heating overload. Bowl (1
0) The refrigerant pipe (6) on the downstream side is bypassed.

In addition, (25) is the heating overload bypass circuit (22).
Is a liquid injection bypass circuit that connects the downstream side of the auxiliary condenser (23) to the refrigerant pipe (6) (suction pipe) on the downstream side of the four-way switching valve (3), and the liquid injection bypass circuit (25) includes Compressor (1),
An injection solenoid valve (26) that opens and closes in conjunction with the operation of (2) and an expansion valve (27) are interposed.

Also, (30) is the receiver, (31) is the accumulator,
(32) is a supercooling coil, (33) is an oil separator, and the lubricating oil separated by the oil separator (33) passes through an oil passage (34) to both compressors (1), (2 ).

Furthermore, in each indoor unit (B) to (F), (TH
1) is a room temperature sensor that is fixedly arranged immediately below the corresponding indoor heat exchanger (10) and detects the temperature of the indoor air (more specifically, the intake air temperature), (TH2) and (TH2)
3) is a temperature sensor for detecting the superheat degree that detects the temperature of the refrigerant before and after the indoor heat exchanger (10). In the outdoor unit (A), (TH4) is a refrigerant discharge temperature sensor that detects the refrigerant discharge temperature of the first and second compressors (1) and (2), and (TH5) is the outdoor heat exchanger during heating operation. Evaporation temperature sensor to detect the evaporation temperature of refrigerant in (4), (TH6)
Is a suction gas temperature sensor for detecting the temperature of suction gas to the first and second compressors (1) and (2). Further, (P1) is a pressure sensor that detects the discharge gas pressure during heating operation, and the suction gas pressure during cooling operation, and (HPS) is a high-pressure pressure switch for protecting the compressor.

Next, FIG. 3 shows an internal configuration of the indoor control device (40) incorporated in each of the indoor units (B) to (F). In the figure, an indoor control device (40) includes a remote control device (41) that is operated by a person in the room and sets a room temperature target value, and an outdoor control device built in the outdoor unit (A). (42) are connected to each other so that signals can be transmitted and received, and the indoor electric expansion valve (11) and the blower fan motor (MF) of the indoor blower fan (10a) are connected to each other, and the blower fan motor ( MF) power supply circuit (46),
Three normally open contacts (RY1) that adjust the rotation speed in four steps
~ (RY3) is installed. In addition, the indoor control device (4
0) is provided with an indoor CPU (45), and the indoor CPU (45)
The detection signals of the room temperature sensor (TH1) and the two temperature sensors (TH2) and (TH3) for grasping the degree of superheat are input to the indoor CPU (45), and the detection signals are input to the detection signals. Based on the calculated superheat of the refrigerant and the air conditioning load, the opening degree of the indoor electric expansion valve (11) and the three normally open contacts (RY1) to (RY
A control relay (not shown) having 3) is operated and controlled.

Next, control in the heating operation by the indoor CPU (45) and the oil recovery operation for the compressors (1) and (2) will be described with reference to FIGS. 4 and 5. First, as will be described from the state transition diagram of FIG. 4, the opening degree of the indoor electric expansion valve (11) belonging to the indoor units (B) to (F) during the heating operation during normal heating operation in the figure. The EV is variably controlled within a predetermined opening change range according to the room temperature (suction air temperature Ta). If the thermoflag TOF = 0 during overheating when the room temperature exceeds the room temperature target value during this normal time, the operation shifts to the stop in the figure through the figure, and the opening EV is set to a small value E here. Control to _K.

Then, at the time of the above stop, a shortage of the lubricating oil of the compressors (1) and (2) occurs due to the operation of the other indoor units, and the recovery of the lubricating oil to the compressors (1) and (2) is requested. When the oil recovery operation flag DAF = 1, the operation proceeds to oil recovery during stop in the figure, the refrigerant circulation system (14) is switched to the cooling cycle by the four-way switching valve (3), and the indoor heat exchanger ( Ten)
When the ventilation fan (10a) is controlled to stop and the opening EV is controlled to the maximum opening value EV _M , and then the oil recovery is completed and the oil recovery operation flag DAF = 0, immediately Transition when stopped inside. Thus, in the case of shifting to this figure, when the thermo flag TOF = 1 and the operation is requested, it shifts to the hot start in the figure and switches the refrigerant circulation system (14) to the heating cycle during the heating operation. However, first, while maintaining the stop control of the blower fan (10a) of the indoor heat exchanger (10), the opening EV is controlled to the set intermediate opening value AS within the predetermined opening change range, and the condensing temperature of the refrigerant is Wait until the temperature rises to a specified value (eg 35 ° C). Then, after that, when the condensing temperature rises to a predetermined value and the hot start end flag HSEF = 1, the heating operation is started by shifting to the normal time in the figure.

Also, at the time of the above hot start, the oil recovery operation flag
When DAF = 1, the operation proceeds to oil recovery during operation in the figure, the refrigerant circulation system (14) is switched to the cooling cycle, the opening EV is controlled to the maximum opening value EV _M , and the operation flag NDF is set in this state. When = 0, the operation shifts to the oil recovery during stop in the above figure in order to stop the heating operation, and conversely, when the operation flag NDF = 1 in this state, the operation shifts to the oil recovery during operation. Furthermore, when the oil recovery is completed by this oil recovery during operation, the operation shifts to the stop in the figure and the opening EV is set to a minute value E _K.
To control.

In addition, the oil recovery operation flag DAF = 1 at the above normal time
If it becomes, the operation shifts to oil recovery during operation in the figure to control the opening EV to the maximum opening value EV _M , while if an overload signal is input, the operation shifts to the overload in the figure. The opening
The EV is controlled to the maximum opening value A _MAX that can be taken according to the room temperature at that time, and returns to the normal time when the input of the overload signal disappears.

Next, the opening control during the above normal time and hot start will be described based on the control flow of FIG.

At step S ₁ , the room temperature (intake air temperature Ta) signal from the room temperature sensor (TH ₁ ) is input, and this intake air temperature value Ta is multiplied by a constant K ₁ to obtain the intake air temperature value Ta. calculated according the indoor electric expansion valve maximum opening value Amax (11), comparing the maximum opening value Amax this that computed as the maximum opening value EV _M on the structure of the electric expansion valve (11) in step S ₂ and, Amax> only if the EV _M, the maximum opening value Amax described above calculated in step S ₃
To the maximum opening value EV _M on the structure.

In step S _4, the minimum opening value at the time of heating operation Amin
Is calculated by the following formula Amin = K ₂ × Amax (K ₂ ; a constant, for example 0.4), and the opening change width of the indoor electric expansion valve (11) is calculated between the maximum opening value Amax and the minimum opening value Amin. and sets the width, the target opening value a _R of the indoor electric expansion valve (11), the suction air temperature value Ta and the deviation between the room temperature target value Ts (Ts-Ta) and on the basis of the maximum opening value Amax the The following formula A _R = K ₃ × (Ts-Ta) × Amax K ₃ ; calculated by a constant, and then the current opening value of the indoor electric expansion valve (11) so that the value corresponds to the temperature deviation (Ts-Ta) EV
Then, the deviation ΔA (ΔA = A _R −EV) between the current opening value EV and the target opening value A _R is calculated.

Then, the determines whether immediately after the hot start at step S _5, only if the YES immediately after completion, to set the opening fixing flag STAF after hot start in step S ₆ in STAF = 1, the electric EV of the expansion valve (11) (initial value)
Is held at the opening value AS (set intermediate opening value within the predetermined opening change range Amax to Amin) during the hot start, and then
A predetermined time T from the end of hot start until the temperature of the room temperature sensor (TH ₁ ) becomes almost equal to room temperature in step S _7.
to determine the presence or absence of course of s, in the case where the elapse of a period of the predetermined time Ts, the routine proceeds immediately to step S ₂₂ described later without performing variable control of the opening degree EV. Then, during the predetermined time Ts is because it is opening fixing flag STAF = 1 in step S _8, without variable control of the opening degree EV, in step S ₉ Upon expiration of the predetermined time Ts, open Degree fixed flag STAF = 0,
Proceeds to step S ₁₀ to start variably control the opening degree of the electronic expansion valve (11).

That is, the opening deviation ΔA between the target opening A _R + side of the small value in step S ₁₀ and S ₁₁ (for example opening value corresponding to 16 pulses) - side small value (e.g., -16 pulses min opening value) and compares corresponding, in opening the small state of .DELTA.A> 16, in order to increase the opening degree EV, set a dose control width ΔEV to +16 in step S _12, .DELTA.A < the opening size of the state of -16, so as to reduce the opening degree EV, set a dose control width ΔEV -16 in step S _13, -16 <almost target opening value a _R of .DELTA.A <16 If it has converged, the control width ΔEV for one time is set to a value of “0” in step S ₁₄ , and then each step is executed.
Assumptions opening EV after control S ₁₅ is calculated by the equation EV = EV + .DELTA.EV.

Then, in step S ₁₆ , the value of the assumed opening EV is set to the maximum opening value Ama.
Compare with x and if EV> Amax is YES, step S
_{In step 17} , the assumed opening EV is corrected to the maximum opening value Amax. Further, when assuming the opening EV is less than the minimum opening value Amin in step S _18, to correct the opening degree EV to the minimum opening value Amin in step S _19. Thereafter, counting the timer at step S _20, the timer value TMS is the sampling period in step S ₂₁ (e.g.
If YES that takes longer than 20 seconds), the above steps S ₁ back. In the case of TMS <20 seconds NO, step S ₂₂ and
Determine the value of each oil recovery operation flag DAF and thermo flag TOF in S _23, in the case of DAF = 1 is to perform the opening control during operation in the oil recovery of the Figure 4, during operation oil recovery during flow (Not shown). When TOF = 0,
In order to perform the opening degree control at the time of stop in the drawing of FIG. 4, the process proceeds to a stop flow (not shown).

Therefore, the room temperature sensor (TH ₁ ) is set by the steps S _{1 to} S ₄ and S _{10 to} S _{23 in} the control flow shown in FIG. 4 and FIG.
When the room is heated, the refrigerant circulation system (14) is switched to the heating cycle by the four-way switching valve (3) and the temperature of the room temperature (suction air temperature Ta) and the room temperature target value Ts Depending on the deviation (Ta-Ts), the predetermined opening change width (Amax
The target opening value A _R is calculated sequentially within
A heating operation control means (50) which variably controls the opening EV of the indoor electric expansion valve (11) by a small value (16 pulse equivalent value) every time the sampling period TMS (for example, 20 seconds) has reached A _R. ) Is composed. In addition, due to and in the drawing of FIG. 4, the refrigerant circulation system (14) is operated at a special time during the oil recovery operation of the compressors (1) and (2), which is different from the heating operation by the heating operation control means (50). ) Is a four-way switching valve (3)
In the cooling operation cycle, a special operation control means (51) is configured to stop the blower fan (10a) of the indoor heat exchanger (10).

Further, at the step S5 in FIG. ₅ , the end time detection means for detecting the end time of the special operation of the oil recovery operation for the compressors (1), (2) by the special operation control means (51). together constitute a (52), in step S ₆ to S _9, receives the output of the end detection means (52), after the end of the special operation, the room temperature of the room detector (TH ₁₎ is During the equal set time Ts, the variable control of the opening EV of the electric expansion valve (11) by the heating operation control means (50) is prohibited,
Set intermediate opening value within the specified opening change range (Amax to Amin)
The control prohibiting means (53) is fixed to the AS.

Therefore, in the above-described embodiment, during normal heating operation of each room, the room temperature sensor (TH ₁ ) detects the intake air temperature Ta of each room and corresponds to each intake air temperature Ta. Temperature deviation (Ts-T
target opening value according to a) A _R ... is respectively calculated, is variably controlled by the indoor electric expansion valve (11) ... actual opening EV is heating operation control means (50), a predetermined opening variation Width (Amax ~
In Amin), since the minute value (16 pulse equivalent value) at a time as appropriate magnitude changes at every elapse of the corresponding target opening value A toward the _R sampling period TMS (e.g. 20 seconds), the air conditioning load is changed Also, in each of the indoor units (B) to (F), the heating capacity corresponds well to this, and each room is satisfactorily cooled and air-conditioned.

On the other hand, during the oil recovery operation (special operation) to the compressors (1) and (2), the refrigerant circulation system (14) is switched to the cooling cycle by the four-way switching valve (3) by the special operation control means (51). At the same time, the blower fan (10a) of the indoor heat exchanger (10) is stopped and controlled, and in this state, the opening degree of the electric expansion valve (11) is controlled to the maximum value EV _M as shown in Fig. 6 (c). As a result, the lubricating oil accumulated in the refrigerant circulation system (14) is successively recovered by the compressors (1) and (2). At this time, the room temperature sensor (TH ₁ ) directly below the indoor heat exchanger (10) (evaporator) is cooled by cold air as shown in FIG. It will be in a lower temperature than.

When the oil recovery operation is completed, the refrigerant circulation system (14) is switched to the heating cycle again, and the indoor blower fan (10a) is maintained in the stopped state. In this state, the opening degree of the electric expansion valve (11) is increased. The EV is controlled to decrease from the maximum value EV _M to the set intermediate opening value AS, and hot start is started. Then, with the hot start, the condensing temperature of the refrigerant rises, and when it reaches a predetermined temperature (for example, 35 ° C.), the hot start ends, the indoor blower fan (10a) operates, and the heating operation starts, In this case, the temperature of the room temperature sensor (TH ₁ ) is warmed by the warm air of the indoor value exchanger (evaporator) and rises during the predetermined time Ts at the beginning of heating operation (immediately after the end of hot start), and becomes almost equal to room temperature. Until
The variable control of the opening EV of the electric expansion valve (11) is prohibited by the control prohibiting means (53) and is fixedly held at the set intermediate opening value AS during the hot start. It is possible to prevent erroneous control of the opening EV in (11). In particular, when the initial opening of the electric expansion valve (11) is set in accordance with the deviation between the room temperature and the room temperature target value in order to increase the heating capacity immediately after the hot start, As shown by the phantom line, this initial opening value is the room temperature sensor (T
Maximum value Am due to the false detection of room temperature due to the low temperature state of H ₁ ).
Since it is set near ax, the sampling period TM
S (e.g., 20 seconds) even if the opening degree EV at every elapse of the minute value (16 pulse equivalent value) at a time reduction control, takes a long time to convergence time to the target opening value A _R. However, as described above, the opening EV is fixed to the set intermediate opening value AS and does not increase, and the deviation from the target opening value A _R is small, so that the target opening value A _R is good in a short time. Will converge to. Therefore, the stability of control is improved, and the comfort of the room can be improved.

In the above embodiment, the oil recovery operation to the compressors (1) and (2) has been described as the special operation mode, but the defrosting operation of the indoor heat exchanger (4) may be used. Further, the application of the present invention is not limited to a multi-type air conditioner, but an ordinary air conditioner in which one indoor unit corresponds to one outdoor unit, or an indoor and outdoor unit integrated It goes without saying that the same can be applied to.

(Invention of Invention) As described above, according to the heat pump type air conditioner of the present invention, at the time of the special operation in which the operation is performed in the cooling cycle, such as the oil recovery operation to the compressor and the defrost operation of the heat exchanger. After the transition from the heating operation to the heating operation, the variable control of the opening degree of the electric expansion valve is forcibly prohibited until the room temperature detecting means disappears the low temperature state due to the operation in the cooling operation cycle at the beginning. Then, the variable control of the opening was started from the state that it became almost equal to the room temperature, so it is possible to prevent erroneous control of the opening, improve the stability and reliability of the control, and improve the indoor comfort. Can be achieved.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 to 6 show an embodiment of the present invention, FIG. 2 is a refrigerant piping system diagram applied to a multi-type air conditioner, FIG. 3 is an internal configuration diagram of an indoor control device, and FIG. FIG. 5 is a state transition diagram between the normal time and the special time, FIG. 5 is a flow chart showing the operation control at the normal time and hot start, and FIG. 6 is an operation explanatory view. (1), (2) ... compressor, (3) ... four-way switching valve,
(4) …… Outdoor heat exchanger, (10) …… Indoor heat exchanger,
(10a) ... indoor blower fan, (11) ... electric expansion valve,
(TH ₁ ): Room temperature sensor, (14): Refrigerant piping system, (5
0) ... heating operation control means, (51) ... special operation control means, (52) ... end time detection means, (53) ... control prohibition means.

Claims (1)

[Claims] 1. A closed circuit comprising a compressor (1, 2), a four-way switching valve (3), a heat source side heat exchanger (4), an electric expansion valve (11) and a load side heat exchanger (10). In the heat pump type air conditioner having the refrigerant circulation system (14), the room temperature detection means (TH ₁ ) arranged near the load side heat exchanger (10) for detecting room temperature, and the refrigerant circulation system (14) ) Is a heating operation cycle and the opening degree of the electric expansion valve (11) is variably controlled according to the deviation between the room temperature of the room temperature detecting means (TH ₁ ) and the room temperature target value, and a heating operation control means (50), A special case where the refrigerant circulation system (14) is set to a cooling operation cycle and the blower fan (10a) of the load side heat exchanger (10) is stopped at a special time different from the heating operation by the heating operation control means (50). The special operation control means (51) is provided with the special operation control means (51). The end time detection means (52) for detecting the end time of the rotation, and the room temperature detection means (T) after receiving the output of the end time detection means (52) after the end of the special operation.
And a control prohibiting means (53) for prohibiting variable control of the opening degree of the electric expansion valve (11) by the heating operation control means (50) during a set time when the temperature of (H ₁ ) becomes equal to room temperature. An electric expansion valve control device for an air conditioner, which is characterized in that: