JPH05248716A - Operation control device for air conditioner - Google Patents

Abstract

PURPOSE:To perform a positive restriction of increasing of a high pressure of refrigerant even in the case that a saturation temperature corresponding to a condensing pressure under an overload condition is rapidly increased. CONSTITUTION:When an outer heat exchanger sensor (Thc) and an inner heat exchanger sensor. The detected in a refrigerant circuit 9 are increased up to the first set temperatures, a capacity of a compressor 1 is decreased by one step N by these heat exchanging sensors. In turn, as an outer heat exchanging temperature Tc during a cooling cycle exceeds 56 deg.C which is lower than the first set temperature, an increasing rate of the outer heat exchanging temperature Tc is judged and the first increasing rate judgment means 12 is operated to output a rapid increasing signal when the increasing rate is more than a predetermined value. There is provided the second capacity decreasing means 14 for decreasing a capacity of the compressor 1 only by two steps N as each of the rapid increasing signals is outputted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner operation controller, and more particularly to a compressor capacity control measure.

[0002]

2. Description of the Related Art Conventionally, an air conditioner has been disclosed in Japanese Patent Laid-Open No.
As disclosed in Japanese Patent Laid-Open No. 147270, a compressor whose capacity is controlled by an inverter, a four-way switching valve, an outdoor heat exchanger, an electric expansion valve, and an indoor heat exchanger are connected in order, and a refrigerant There is one in which the operating frequency of the inverter is controlled on the basis of the evaporation temperature to control the capacity of the compressor.

Further, in the air conditioner, the saturation temperature equivalent to the condensation pressure is detected, for example, the condensation temperature of the outdoor heat exchanger during the cooling cycle is detected, and when the condensation temperature rises, a predetermined temperature is reached. In some cases, the operating frequency of the inverter is reduced by a predetermined amount to reduce the compressor capacity and suppress the increase in high-pressure refrigerant pressure.

[0004]

In the above-mentioned air conditioner, when the high pressure rises, only one predetermined temperature is set so that the compressor capacity is reduced.
There is a problem that the high-pressure refrigerant pressure on the discharge side of the compressor rises to an abnormal pressure value at the time of start-up and the high-pressure switch operates.

That is, in an overloaded state such as at the time of start-up, the condensing temperature may rise rapidly, and at this time, even if the compressor capacity is reduced while the condensing temperature exceeds a predetermined temperature,
There has been a problem that the drooping of the operating frequency cannot catch up, the high pressure refrigerant pressure overshoots the abnormal pressure value, and the high pressure switch is activated, so that the air conditioning operation is stopped.

The present invention has been made in view of the above circumstances, and is intended to reliably suppress the increase in the high-pressure refrigerant pressure even when the condensation pressure-equivalent saturation temperature sharply increases due to overload or the like. ..

[0007]

In order to achieve the above object, the means taken by the present invention is to determine a sudden rise in the saturation temperature equivalent to the condensing pressure and increase the decrease in the compressor capacity at the sudden rise. It was done.

Concretely, as shown in FIG. 1, the means taken by the invention according to claim 1 is as follows.
It is premised on an air conditioner including a refrigerant circuit (9) in which a heat source side heat exchanger (3), an expansion mechanism (5), and a use side heat exchanger (6) are sequentially connected.

A saturation temperature detecting means (Thc, The) for detecting a saturation temperature corresponding to the condensation pressure in the refrigerant circuit (9).
When the saturation temperature equivalent to the condensation pressure detected by the saturation temperature detecting means (Thc, The) rises to the first set temperature, the compressor (1)
To reduce the capacity of the first predetermined amount by a first predetermined amount
Capacity lowering means (11) is provided. Furthermore, when the condensation pressure equivalent saturation temperature detected by the saturation temperature detecting means (Thc, The) rises to a second set temperature lower than the first set temperature, the rate of increase of the condensation pressure equivalent saturation temperature is determined, An increase rate determination means (12) is provided which outputs a sudden increase signal when the increase rate is a predetermined value or more. In addition, when the rate of rise determination means (12) outputs a sudden rise signal, the second capacity reducing means (14) that reduces the capacity of the compressor (1) by a second predetermined amount larger than the first predetermined amount. The configuration is provided.

Further, the means taken by the invention according to claim 2 is, in place of the rate of rise determination means (12) in the invention according to claim 1, during the cooling cycle detected by the saturation temperature detecting means (Thc, The). When the saturation pressure-equivalent saturation temperature rises to a second set temperature that is lower than the first set temperature, the rate of increase of the condensation pressure-equivalent saturation temperature is determined. First rising rate judging means for outputting (12)
And, when the condensation pressure equivalent saturation temperature during the heating cycle detected by the saturation temperature detecting means (Thc, The) rises to the third set temperature lower than the second set temperature, the rate of increase of the condensation pressure equivalent saturation temperature. Second rising rate determining means (13) for outputting a sudden rising signal when the rising rate is equal to or more than a predetermined value.
And are provided. Then, the second capacity lowering means (14), when the first rising rate judging means (12) or the second rising rate judging means (13) outputs a sudden rising signal, the compressor
The capacity of (1) is reduced by a second predetermined amount larger than the first predetermined amount.

[0011]

With the above structure, in the invention according to claim 1,
First, in the refrigerant circuit (9), for example, the liquid refrigerant condensed and liquefied in the heat source side heat exchanger (3) is decompressed by the expansion mechanism (5) and then evaporated in the use side heat exchanger (6). Then it returns to the compressor (1).

During the air conditioning operation, the saturation temperature detecting means (Thc, The) detects the saturation temperature corresponding to the condensation pressure,
For example, during the cooling cycle, the heat source side heat exchanger (3)
The external heat exchange temperature Tc is read from the external heat exchange sensor (Thc) provided in the.

Thereafter, the rate of rise determination means (12) determines whether the outside heat exchange temperature Tc, which is the saturation temperature equivalent to the condensation pressure, exceeds a second predetermined temperature, for example, 56 ° C., and determines the rate of temperature rise. Then, for example, it is determined whether or not the temperature rises by 2 ° C. or more in 15 seconds. And, the outside heat exchange temperature Tc is 56 ° C. or lower,
Alternatively, if the temperature does not rise by 2 ° C. or more in 15 seconds even if it exceeds 56 ° C., the first capacity lowering means (11) determines the external heat exchange temperature Tc.
Exceeds a first predetermined temperature, for example 62 ° C., the capacity of the compressor (1) is reduced by a first predetermined amount.

On the other hand, when the rise rate determining means (12) determines that the external heat exchange temperature Tc exceeds 56 ° C. and rises by 2 ° C. or more in 15 seconds, it outputs a rapid rise signal and the second capacity lowering means. (14) The capacity of the compressor (1) is larger than the first predetermined amount
Decrease by a predetermined amount. As a result, the capacity of the compressor (1) decreases greatly when the external heat exchange temperature Tc rises sharply.

Further, in the invention according to claim 2, during the cooling cycle, the increase rate determining means (12) of the invention of claim 1 becomes the first increase rate determining means (12), and the compressor is the same as in claim 1. Control the capacity of (1).

On the other hand, during the heating cycle, the second rise rate determining means (13) is the condensation pressure equivalent saturation temperature detected by the internal heat exchange sensor (The) provided in the utilization side heat exchanger (6). It is determined whether the internal heat exchange temperature Te exceeds a third set temperature, for example, 54 ° C., and the temperature rise rate is determined.
It is determined whether or not the temperature has risen by 2 ° C. or more in 15 seconds. And, the internal heat exchange temperature Te is 54 ° C. or lower, or 54 ° C.
If the temperature does not rise more than 2 ° C for 15 seconds even if the temperature exceeds the limit, the first capacity reducing means (11) controls the compressor (1) as described above.
Will control the capacity of.

Further, when the second rate-of-increasing determination means (13) determines that the internal heat exchange temperature Te exceeds 54 ° C. and rises by 2 ° C. or more in 15 seconds, it outputs a sudden increase signal and outputs the second capacitance. The lowering means (14) lowers the capacity of the compressor (1) by a second predetermined amount.

[0018]

Therefore, according to the invention of claim 1,
Compressor when the rate of increase in saturation temperature equivalent to the condensation pressure is large
Since the lowering capacity of (1) is increased, it is possible to reliably suppress the increase of the high pressure refrigerant pressure in an overload state such as at the time of starting. As a result, since the operation of the high pressure switch can be suppressed, the air conditioning operation can be continued and the comfort can be improved.

Further, according to the second aspect of the present invention, the capacity of the compressor (1) is lowered during the heating cycle in a state where the saturation temperature corresponding to the condensation pressure is lower than during the cooling cycle, so that it depends on the pipe length. Even when the responsiveness is poor, the increase in the high-pressure refrigerant pressure can be reliably suppressed, and the operation of the high-pressure pressure switch can be suppressed, so that the comfort can be improved.

[0020]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 2 shows a refrigerant piping system of an air conditioner to which the present invention is applied, which is a so-called separate type in which one indoor unit (B) is connected to one outdoor unit (A). Is.

The outdoor unit (A) includes a scroll type compressor (1) whose operating frequency is variably adjusted by an inverter, and a solid line in the figure during cooling operation and a broken line in the figure during heating operation. Four-way switching valve to replace (2)
And an outdoor heat exchanger that is a heat source side heat exchanger that functions as a condenser during cooling operation and as an evaporator during heating operation.
(3), a decompression section (20) for decompressing the refrigerant, and a compressor
An accumulator (7) for removing the liquid refrigerant in the suction refrigerant, which is provided in the suction pipe of (1), is arranged as a main device. Further, the indoor unit (B) is provided with an indoor heat exchanger (6) which is a utilization side heat exchanger that functions as an evaporator during cooling operation and as a condenser during heating operation. The compressor (1), the four-way switching valve (2), the outdoor heat exchanger (3), the pressure reducing section (20), the indoor heat exchanger (6), and the accumulator (7) are connected to the pipe ( 8) are connected sequentially,
A refrigerant circuit (9) is configured so that heat is transferred by circulating the refrigerant.

Here, the decompression section (20) includes a bridge-shaped rectifier circuit (8a) and a pair of connection points in the rectifier circuit (8a).
A common path (8a) connected to (P, Q), and the common path (8a)
Includes a receiver (4) for storing the liquid refrigerant, an auxiliary heat exchanger (3a) for the outdoor heat exchanger (3), and an electric expansion mechanism that is an expansion mechanism that has a pressure reducing function and a flow rate adjusting function for the liquid refrigerant. Valve (5)
And are arranged in series. And the rectifying circuit (8a)
The other pair of connection points (R, S) in the
The piping (8) on the (3) side and the piping (8) on the indoor heat exchanger (6) side are connected. Furthermore, the rectifier circuit (8a) connects the upstream connection point (P) of the common path (8a) and the connection point (S) of the outdoor heat exchanger (3) side from the external heat exchanger (3). Indoor heat exchange with the first inflow passage (8b1) equipped with the first check valve (D1) that allows only refrigerant flow to the receiver (4), the upstream connection point (P) of the common passage (8a) The indoor heat exchanger (6) is connected to the connection point (R) on the side of the heat exchanger (6).
Second inflow path (8b2) equipped with a second check valve (D2) that allows only the flow of refrigerant from the receiver to the receiver (4), the downstream connection point (Q) of the common path (8a) and the indoor heat A first check valve (D3) that connects the connection point (R) on the exchanger (6) side and allows only the refrigerant to flow from the electric expansion valve (5) to the indoor heat exchanger (6). Outflow channel (8
c1), the downstream side connection point (Q) of the common path (8a) and the connection point (S) on the outdoor heat exchanger (3) side, and the electric expansion valve (5) to the outdoor heat exchanger (3). The second outflow passage (8c2) provided with the fourth check valve (D4) which allows only the refrigerant flow to (4).

In addition, the common path (8
Between both connection points (P, Q) in a), the capillary tube (C)
A liquid seal prevention bypass passage (8f) is provided,
The liquid seal prevention bypass passage (8f) prevents liquid seal when the compressor (1) is stopped, while opening and closing between the upper part of the receiver (4) and the downstream side of the common passage (8a). A degassing passage (4a) equipped with a valve (SV) is connected. The degree of pressure reduction of the capillary tube (C) is set to be sufficiently higher than that of the electric expansion valve (5), and the function of adjusting the refrigerant flow rate by the electric expansion valve (5) during normal operation is maintained well. It is designed to be profitable.

Further, (F1 to F4) are filters for removing dust in the refrigerant, and (ER) is a silencer for reducing the operation noise of the compressor (1).

Further, the air conditioner is provided with sensors, (Thd) is a discharge pipe sensor (Tha) arranged in the discharge pipe of the compressor (1) for detecting the discharge pipe temperature Td. Is
An outdoor suction sensor, which is located at the air suction port of the outdoor unit (A) and detects the suction air temperature Ta, which is the outside air temperature, (Thc)
Is placed in the outdoor heat exchanger (3) and has an outside heat exchange sensor (saturation temperature) that detects the outside heat exchange temperature Tc, which is the condensation temperature equivalent to the condensation pressure during cooling operation and the evaporation temperature during heating operation. (Detection means), (Thr) is the indoor unit (B)
The intake air temperature that is the room temperature that is placed at the air intake port of
Indoor suction sensor that detects Tr, (The) is an indoor heat exchanger
The internal heat exchange sensor (saturation temperature detecting means) for detecting the internal heat exchange temperature Te, which is arranged in (6), becomes the evaporation temperature during the cooling operation and becomes the condensation temperature corresponding to the condensation pressure during the heating operation. ) Is a high-pressure pressure switch that is a high-pressure detection unit that detects the high-pressure refrigerant pressure and outputs a high-pressure signal when the high-pressure refrigerant pressure rises excessively, and (LPS) detects the low-pressure refrigerant pressure. A low pressure switch that is turned on when the low pressure refrigerant pressure is excessively low and outputs a low pressure signal.

The output signals of the sensors (Thd, ..., The) and switches (HPS, LPS) are output to the controller (10).
The controller (10) is configured to control the air conditioning operation based on the input signal.

In the above-mentioned refrigerant circuit (9), during the cooling operation, the liquid refrigerant condensed and liquefied in the outdoor heat exchanger (3) flows from the first inflow passage (8b1), and the first check valve (D1) ) And then stored in the receiver (4), decompressed by the electric expansion valve (5), then evaporated in the indoor heat exchanger (6) through the first outflow path (8c1) and returned to the compressor (1). While circulating, during heating operation,
Liquid refrigerant condensed and liquefied in the indoor heat exchanger (6) flows in from the second inflow path (8b2), passes through the second check valve (D2), and is received.
After being stored in (4) and decompressed by the electric expansion valve (5), the second
Compressor by evaporating in the outdoor heat exchanger (3) via the outflow passage (8c2)
The cycle returns to (1).

On the other hand, as a feature of the present invention, the controller (10) includes a first capacity lowering means (11) and a first rising rate judging means (11) for controlling the capacity of the compressor (1). 12)
A second rate of increase determination means (13) and a second capacity reduction means (14)
And are provided.

Therefore, the compressor (1) divides the operating frequency of the inverter into 20 steps N from zero to the maximum frequency, and sets each step N based on the discharge pipe temperature Td. Is configured to control the capacity of the.

On the other hand, in the first capacity lowering means (11), the external heat exchange temperature Tc and the internal heat exchange temperature Te, which are the condensation temperatures detected by the external heat exchange sensor (Thc) and the internal heat exchange sensor (The), are When the temperature rises to the first set temperature, specifically, it rises to 62 ° C. in the cooling cycle, and 56 ° C. and 5 ° C. in the heating cycle.
When the temperature rises to 7.5 ° C., the capacity of the compressor (1) is decreased by a preset first predetermined amount, that is, the operating frequency by one step N.

The first capacity lowering means (11) changes the external heat exchange temperature Tc, which is the condensation temperature during the cooling cycle detected by the external heat exchange sensor (Thc), to the second set temperature lower than the first set temperature. When it rises, specifically, when it rises above 56 ° C. in the cooling cycle, the rate of rise of the outside heat exchange temperature Tc is judged, and when the rate of rise exceeds a predetermined value, that is, 2 ° C. in 15 seconds, a rapid rise signal Is configured to output.

The second capacity lowering means (14) changes the internal heat exchange temperature Te, which is the condensation temperature during the heating cycle detected by the internal heat exchange sensor (The), to the third set temperature lower than the second set temperature. When the temperature rises, specifically, when the temperature rises above 54 ° C. in the heating cycle, the rate of increase of the internal heat exchange temperature Te is determined, and when the rate of increase exceeds a predetermined value, that is, 2 ° C. in 15 seconds, a rapid increase signal Is configured to output. The reason why the set temperature during the heating cycle is lower than that during the cooling cycle is that the pipe length from the compressor (1) to the indoor heat exchanger (6) is longer than the pipe length from the outdoor heat exchanger (3). Therefore, the responsiveness is poor.

The second capacity lowering means (14) reduces the capacity of the compressor (1) when the first rising rate judging means (12) or the second rising rate judging means (13) outputs a rapid rising signal. The capacity is reduced by a second predetermined amount that is larger than the first predetermined amount, that is, two steps N.

Next, the capacity control operation of the compressor (1) will be described based on the control flow of FIG.

First, in the air conditioning operation during the cooling cycle, first, in step ST1, it is determined whether the sampling timer T exceeds 5 seconds or 0 seconds, that is, sampling is performed every 5 seconds. It is determined whether the time has come, and until the sampling time comes, the process moves from step ST1 to step ST2, the non-change area of the compressor (1) is released, and the capacity of the compressor (1) can be changed. And return. When the sampling time comes, the process moves from step ST1 to step ST3 to read the external heat exchange temperature Tc from the external heat exchange sensor (Thc) and set the sampling timer T to zero.

After that, from step ST3 to step ST
4, the first rising rate determination means (12) determines whether or not the external heat exchange temperature Tc, which is the condensation temperature, exceeds 56 ° C., and the previously detected external heat exchange temperature Tc and the current external heat It is determined whether the temperature difference from the intersection temperature Tc is 2 ° C. or more. That is, since the sampling time is 5 seconds, it is determined whether or not the temperature rises by 2 ° C. or more in 15 seconds. And the outside heat exchange temperature Tc
Is less than 56 ° C, or exceeds 56 ° C, 2 in 15 seconds
If the temperature has not risen above 0 ° C., the determination in step ST4 is NO, the process proceeds to step ST2, and normal capacity control is performed. Specifically, the capacity step N of the compressor (1) is set based on the discharge pipe temperature Td, and
The capacity lowering means (11) lowers the capacity of the compressor (1) by 1 step N when the external heat exchange temperature Tc exceeds 62 ° C.

On the other hand, in step ST4, the first heat-up rate determining means (12) determines that the external heat exchange temperature Tc, which is the condensation temperature, is 56.
If it is judged that the temperature exceeds 2 ℃ and rises by 2 ℃ or more in 15 seconds, a rapid rise signal is output and the judgment in step ST4 is YES.
Then, the process moves to step ST5. The step
In ST5, it is determined whether or not the capacity step N of the compressor (1) is 4 or more. If the capacity is 4 or more, the process proceeds from step ST5 to step ST6 and the step change amount dN is set to -2. To do. That is, the first rising rate determination means (12)
The second capacity reducing means (14) sets the capacity of the compressor (1) to decrease by 2 steps N based on the above judgment.

Then, in step ST7, the sampling timer T is started, and then in step ST8, it is judged whether the capacity step N of the compressor (1) is 2, that is, the capacity When the step N is 0, the operating frequency is 0 and the compressor (1) is stopped. When the capacity step N is 2, the capacity of the compressor (1) is It is set to the minimum, and if it is not this minimum capacity, the determination in step ST8 is N.
It becomes O.

Then, in step ST9, the compressor
(1) The non-change region control is performed, the capacity of the compressor (1) is fixed for a predetermined time to prevent hunting of capacity change, and in step ST10, the capacity step N is linked with the electric expansion valve (5). Predicting the amount of change in step ST11 and interlocking the electric expansion valve (5) in step ST11, and then controlling the operating frequency of the compressor (1) in step ST12, that is, the second capacity lowering means (14) , Capacity step N of compressor (1) is 2 step N
Will only lower it. After that, step ST2 above
Then, the above operation is repeated. As a result,
When the outside heat exchange temperature Tc rises sharply, the capacity of the compressor (1) is increased to 2
It will be decreased by step N.

In step ST5, the compressor
If the capacity step N in (1) is smaller than 4, the determination is NO.
Then, the process proceeds to step ST13, and since the capacity of the compressor (1) is low, the step change amount dN is set to -1 and step ST7
Will move to. Then, the above operation is performed.

In step ST8, the compressor
If the capacity step N of (1) is 2, the determination is YES, the process proceeds to step ST14, the frequency OFF circuit is executed, that is, if the capacity step N is 2, the compressor
Since the capacity of (1) is the lowest, stop the operation of the compressor (1). After that, the process proceeds to step ST15, the thermostat is turned off, and the process returns to the main flow.

Further, during the heating cycle, in step ST4, the second rate of rise determination means (13) determines whether the internal heat exchange temperature Te, which is the condensation temperature, exceeds 54 ° C., and for 15 seconds. It is determined whether or not the temperature has risen by 2 ° C or more. When the internal heat exchange temperature Te is 54 ° C. or lower, or when it exceeds 54 ° C. and has not risen by 2 ° C. or higher in 15 seconds, the process proceeds to step ST2, and normal capacity control is performed. Specifically, the capacity step N of the compressor (1)
Is set based on the discharge pipe temperature Td, and the first capacity lowering means (11) lowers the capacity of the compressor (1) by 1 step N when the internal heat exchange temperature Te exceeds 56 ° C. When the internal heat exchange temperature Te exceeds 57.5 ° C, the capacity of the compressor (1) is decreased by 1 step N.

On the other hand, in step ST4, the second heat-up rate determining means (13) determines that the internal heat exchange temperature Te, which is the condensation temperature, is 54.
If it is determined that the temperature has exceeded 0 ° C. and has increased by 2 ° C. or more in 15 seconds, a rapid increase signal is output and the process proceeds to step ST5. Then, thereafter, as in the case of the cooling cycle, the second capacity reducing means (14) reduces the capacity of the compressor (1) by 2 steps N based on the determination of the second increase rate determining means (13). I will let you. As a result, the capacity of the compressor (1) is decreased by 2 steps N when the internal heat exchange temperature Te rises sharply.

Therefore, according to the present embodiment, when the increase rate of the external heat exchange temperature Tc or the internal heat exchange temperature Te, which is the condensation temperature, is large, the decreasing capacity of the compressor (1) is made large. It is possible to reliably suppress an increase in high-pressure refrigerant pressure in an overload state such as at the time of starting. As a result, since the operation of the high pressure switch (HPS) can be suppressed, the air conditioning operation can be continued and the comfort can be improved.

Further, since the capacity of the compressor (1) is reduced in the heating cycle in a state where the condensing temperature is lower than in the cooling cycle, the high pressure refrigerant pressure is surely maintained even when the response due to the pipe length is poor. Since the rise can be suppressed and the operation of the high pressure switch (HPS) can be suppressed, the comfort can be improved.

Further, as an embodiment of the invention according to claim 1, in the step ST4, the condensing temperature which is the second set temperature is set to the same temperature during the cooling cycle and the heating cycle. The first rate-of-increasing determination means (12) of the previous embodiment constitutes one rate-of-increasing determination means (12) for determining a sudden rise in the condensation temperature. Other configurations and operations are similar to those in the cooling cycle of the previous embodiment. As a result, similarly to the previous embodiment, it is possible to reliably suppress the rise of the high pressure refrigerant pressure in the overload state such as at the time of starting.

In each of the embodiments, the separate type air conditioner has been described, but it goes without saying that the present invention can be applied to various air conditioners.

In each of the embodiments, the external heat exchange sensor (Thc) and the internal heat exchange sensor (Thc) are used as the saturation temperature detecting means.
Although e) is provided, it goes without saying that a pressure sensor or the like may be used.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a refrigerant circuit diagram showing a refrigerant piping system of the air conditioner.

FIG. 3 is a control flow chart showing a control for reducing the capacity of a compressor.

[Explanation of symbols]

 1 Compressor 3 Outdoor heat exchanger (heat source side heat exchanger) 5 Electric expansion valve (expansion mechanism) 6 Indoor heat exchanger (use side heat exchanger) 9 Refrigerant circuit 10 Controller 11 1st capacity reduction means 12 Rate of rise determination Means (first rise rate determination means) 13 Second rise rate determination means 14 Second capacity reduction means Thc Outer heat exchange sensor (saturation temperature detection means) The Inner heat exchange sensor (saturation temperature detection means)

Claims (2)

[Claims] 1. A refrigerant circuit (1) comprising a variable capacity compressor (1), a heat source side heat exchanger (3), an expansion mechanism (5) and a utilization side heat exchanger (6) connected in order. In the air conditioner equipped with 9), the saturation temperature detecting means (Thc, The) for detecting the saturation temperature equivalent to the condensation pressure in the refrigerant circuit (9), and the condensation detected by the saturation temperature detecting means (Thc, The) When the pressure-equivalent saturation temperature rises to the first set temperature, the first capacity decreasing means (11) for decreasing the capacity of the compressor (1) by a preset first predetermined amount, and the saturation temperature detecting means (Thc, When the condensation pressure equivalent saturation temperature detected by (The) rises to a second set temperature lower than the first set temperature, the rate of increase of the condensation pressure equivalent saturation temperature is determined, and the increase rate is equal to or more than a predetermined value. , A rising rate determination means (12) for outputting a rapid rising signal, and when the rising rate determination means (12) outputs a rapid rising signal, the compressor ( An operation control device for an air conditioner, comprising: a second capacity reducing means (14) for reducing the capacity of 1) by a second predetermined amount larger than the first predetermined amount. 2. A variable capacity compressor (1), a heat source side heat exchanger (3), an expansion mechanism (5), and a use side heat exchanger (6) are connected in sequence to provide a cooling cycle and heating. In an air conditioner equipped with a refrigerant circuit (9) capable of reversible operation in a cycle, a saturation temperature detection means (Thc, The) for detecting a saturation temperature equivalent to the condensation pressure in the refrigerant circuit (9), and the saturation temperature detection When the saturation temperature corresponding to the condensation pressure detected by the means (Thc, The) rises to the first set temperature, the capacity of the compressor (1) is decreased by a preset first predetermined amount. And, when the saturation temperature equivalent to the condensation pressure during the cooling cycle detected by the saturation temperature detecting means (Thc, The) rises to the second set temperature lower than the first set temperature, the rate of increase of the condensation pressure equivalent saturation temperature. And the rise rate is equal to or higher than a predetermined value, a first rise rate determination that outputs a sudden rise signal When the saturation temperature equivalent to the condensation pressure during the heating cycle detected by the stage (12) and the saturation temperature detecting means (Thc, The) rises to the third preset temperature lower than the second preset temperature, the condensation pressure equivalent saturation A rate of temperature increase is determined, and when the rate of increase is equal to or higher than a predetermined value, a second rate-of-increasing determination means (13) that outputs a sudden increase signal and the first rate-of-increasing determination means (12) or the second rate of increase Judgment means (1
3) is provided with a second capacity reducing means (14) for decreasing the capacity of the compressor (1) by a second predetermined amount larger than the first predetermined amount when the sudden increase signal is output. Operation control device for air conditioner.