JP3308845B2 - Cooling start control device for air conditioner with refrigerant heating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling start control device for a refrigerant heating type air conditioner.

[0002]

2. Description of the Related Art Conventionally, in an air conditioner using a general air heat source as a main heat source, a high / low pressure bypass circuit is used at the start of a cooling operation for the purpose of capacity control, avoiding liquid back of a compressor, and reducing noise. Refrigeration cycles and control schemes for bypassing gas to low pressure gas have been proposed. But,
In the cooling operation of the refrigerant heating air conditioner, a high / low pressure bypass circuit is not particularly configured.

FIG. 8 shows a conventional example of a refrigerant-heated air conditioner (Japanese Patent Application No. 60-264522). 8, 30 is a frequency control device, 31 is a high voltage detection element, 3
2 is a low pressure detecting element, 33 is a second decompression device (for example, an electronic expansion valve or the like), 34 is a compressor, 35 is a four-way valve, 36 is an outdoor heat exchanger, 37 is a first decompression device, and 38 is a chamber. Inner heat exchanger, 39 is a decompressor, 40 is an indoor piping temperature sensor, 4
1 is a suction temperature sensor, 42 is an indoor side control device, 43 is a compressor drive unit, and 44 is a power supply.

When the operation of the air conditioner is started, or when the set temperature is largely changed, the driving frequency may increase rapidly, the discharge pressure may increase, and the load may temporarily increase. Therefore, the outputs of both the high-pressure detection element 31 and the low-pressure detection element 32 are input to the frequency control device 30, and the output opens the second pressure reducing device 33 to reduce the load. Then, when the discharge pressure is dispersed to the heat exchanger and the like and the pressure decreases, the second pressure reducing device 33 is gradually closed to stabilize the refrigerant system while maintaining the rotation of the compressor at the target frequency. In this way, the increase in the load on the compressor due to the temporary increase in the discharge pressure can be gradually absorbed while taking into account the delay in the refrigerant system, and the operation can be performed without reducing the drive frequency. Can be used for

As described above, the bypass circuit having the second decompression device 33 is provided between the refrigerant discharge pipe and the suction pipe of the compressor, and the control element of the second decompression device 33 is provided. By adjusting the difference between the high and low pressures of the refrigerant system, the capacity of the compressor and inverter can be fully utilized.

[0006]

At present, there is a demand in the market for a refrigerant-heated air conditioner, and there is a demand for long piping for mounting indoor units on the second and third floors. However, if a long pipe is used, the amount of refrigerant becomes a multi-refrigerant. If the cooling operation is performed in the state of the multi-refrigerant, the liquid refrigerant suddenly returns at the time of startup, and the variable frequency compressor causes the liquid compression. A technique to avoid this is required.

[0007] For this reason, it is necessary to cope with long piping and multiple refrigerants in the cooling operation of the heat transfer type air conditioner. If this countermeasure is performed by a conventional high / low pressure bypass at the time of starting the cooling operation, there is a problem that a dedicated bypass circuit is required, the structure is complicated, and the cost is increased.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems.
It is an object of the present invention to provide a cooling start control device of a refrigerant heating type air conditioner capable of coping with multiple refrigerants and realizing the reliability of a variable frequency compressor at low cost.

[0009]

According to a first aspect of the present invention, there is provided a cooling start control apparatus for a refrigerant heating type air conditioner, comprising: a variable frequency compressor, a four-way valve, an outdoor heat exchanger, a first decompressor, a first decompressor. A cooling-operable refrigeration cycle in which a check valve, a second pressure reducer, an indoor heat exchanger, a four-way valve, a second check valve, and a variable frequency compressor are connected in this order in a ring shape; Machine,
A four-way valve, an indoor heat exchanger, a third check valve connected in parallel with the second decompressor, a two-way valve, a heater, and a variable frequency compressor are connected in this order in a ring-like manner to enable heating operation. Upon receiving the refrigerant heating type refrigeration cycle and the cooling start signal, the variable frequency compressor is started.
After the elapse of the clock time, the two-way valve is controlled to open,
After the elapse of the second clock time from the opening direction control, the two-way valve is closed.
Is obtained and control means for controlling the.

According to the cooling start control device for a refrigerant heating type air conditioner according to the present invention, when the two-way valve at the inlet of the heater is controlled to open, the refrigerant at the time of starting the cooling operation becomes a circuit at the time of using the heating operation. And return to the variable frequency compressor, the hot gas refrigerant returns to the variable frequency compressor even if the connection pipe is a long pipe. That is, the refrigerant and oil that have flowed out of the variable frequency compressor are quickly returned to the variable frequency compressor, and abnormal pressure drop and oil drop of the variable frequency compressor can be prevented. In addition, by adding hot gas to the liquid bag at the time of starting, the liquid bag can be avoided, and highly reliable start control can be performed. Furthermore, since a circuit for heating operation is used, a bypass circuit dedicated to cooling is not required. Ma
The opening direction of the two-way valve is controlled by starting the variable frequency compressor.
By delaying, when the variable frequency compressor starts,
No excessive load is applied to the variable frequency compressor without causing
Start control that is not possible and realizes highly reliable start control.
Wear. After a lapse of a predetermined time, the closing direction of the two-way valve is controlled.
Control to minimize cooling capacity degradation, and
Minimizing sound generation from variable frequency compressors
it can.

[0011]

According to a second aspect of the present invention, there is provided a cooling start control apparatus for a refrigerant heating type air conditioner, comprising: a variable frequency compressor, a four-way valve, an outdoor side.
Heat exchanger, first pressure reducer, first check valve, second pressure reduction
Heat exchanger, indoor heat exchanger, four-way valve, second check valve, variable frequency
Cooling operation is possible by connecting several compressors in this order in a ring.
Refrigeration cycle, variable frequency compressor, four-way valve, indoor heat
Exchanger, a third check valve connected in parallel with the second decompressor,
The two-way valve, heater, and variable frequency compressor are connected in this order in a ring.
A refrigerant-heated refrigeration cycle operable for heating,
Upon receiving the cooling start signal, start the variable frequency compressor,
At the same time, the two-way valve is controlled to open, and when the detected temperature of the variable frequency compressor is lower than the first set temperature, after the elapse of the third clock time, the two-way valve is controlled to close, and the variable frequency compressor is controlled. When the detected temperature of the machine is equal to or higher than the first set temperature, the control means controls the two-way valve in the closing direction after a fourth clock time longer than the third clock time .

[0013] According to the cooling start control apparatus according to claim 2 refrigerant heating type air conditioner according, the two-way valve of the heater inlet opening direction
When the cooling operation is started, the refrigerant at the time of starting the cooling operation uses the heating operation.
Return to the variable frequency compressor through the circuit of the time, the connection
Hot to variable frequency compressor even if long piping is used
The gas refrigerant will return. That is, variable frequency compression
Quickly returns refrigerant and oil from the compressor to the variable frequency compressor
To prevent abnormal pressure drop and oil drop of the variable frequency compressor
be able to. Also, hot against liquid back at startup
By adding gas, liquid back can be avoided and high reliability
Startup control is possible. In addition, use the circuit for heating operation.
This eliminates the need for a cooling-only bypass circuit. Ma
In addition, the temperature of the variable frequency compressor is detected to control the control time of the two-way valve, and it is determined whether the startup control of the variable frequency compressor is cold or hot. The opening direction time of the two-way valve is shortened because the number is reduced, and the opening time of the two-way valve is increased because the amount of liquid back increases when hot. That is, by determining the amount of liquid back to the variable frequency compressor based on the temperature of the variable frequency compressor and changing the bypass time, the refrigerant is accumulated by the heat radiation action of the outdoor heat exchanger due to the operation of the variable frequency compressor. , The reliability of the variable frequency compressor can be ensured, and efficient two-way valve control can be realized.

According to a third aspect of the present invention, there is provided a cooling start control apparatus for a refrigerant heating type air conditioner, comprising: a variable frequency compressor, a four-way valve, and an outdoor side.
Heat exchanger, first pressure reducer, first check valve, second pressure reduction
Heat exchanger, indoor heat exchanger, four-way valve, second check valve, variable frequency
Cooling operation is possible by connecting several compressors in this order in a ring.
Refrigeration cycle, variable frequency compressor, four-way valve, indoor heat
Exchanger, a third check valve connected in parallel with the second decompressor,
The two-way valve, heater, and variable frequency compressor are connected in this order in a ring.
A refrigerant-heated refrigeration cycle operable for heating,
Upon receiving the cooling start signal, start the variable frequency compressor,
At the same time, the two-way valve is controlled to open, and when the outside air temperature is higher than the second set temperature, after the elapse of a fifth clock time, the two-way valve is controlled to be closed, and the outside air temperature is controlled to the second set temperature. In the following cases, a control means is provided for controlling the two-way valve in the closing direction after a sixth clock time longer than the fifth clock time has elapsed.
You.

According to the third aspect of the present invention, the two-way valve at the inlet of the heater is opened in the opening direction.
When the cooling operation is started, the refrigerant at the time of starting the cooling operation uses the heating operation.
Return to the variable frequency compressor through the circuit of the time, the connection
Hot to variable frequency compressor even if long piping is used
The gas refrigerant will return. That is, variable frequency compression
Quickly returns refrigerant and oil from the compressor to the variable frequency compressor
To prevent abnormal pressure drop and oil drop of the variable frequency compressor
be able to. Also, hot against liquid back at startup
By adding gas, liquid back can be avoided and high reliability
Startup control is possible. In addition, use the circuit for heating operation.
This eliminates the need for a cooling-only bypass circuit. Ma
Also, by controlling the control time of the two-way valve by detecting the outside air temperature, it is determined whether or not the liquid refrigerant easily accumulates in the outdoor unit. The higher the temperature, the shorter the opening time of the two-way valve. That is, by judging the amount of liquid back due to the amount of accumulated refrigerant in the outdoor heat exchanger at the outside air temperature and changing the bypass time, liquid back is properly avoided to ensure the reliability of the variable frequency compressor. And efficient two-way valve control can be realized.

According to a fourth aspect of the present invention, there is provided a cooling start control device for a refrigerant heating type air conditioner, comprising: a variable frequency compressor, a four-way valve, an outdoor side.
Heat exchanger, first pressure reducer, first check valve, second pressure reduction
Heat exchanger, indoor heat exchanger, four-way valve, second check valve, variable frequency
Cooling operation is possible by connecting several compressors in this order in a ring.
Refrigeration cycle, variable frequency compressor, four-way valve, indoor heat
Exchanger, a third check valve connected in parallel with the second decompressor,
The two-way valve, heater, and variable frequency compressor are connected in this order in a ring.
A refrigerant-heated refrigeration cycle operable for heating,
Upon receiving the cooling start signal, start the variable frequency compressor,
Control means for simultaneously controlling the two-way valve in the opening direction, starting the outdoor blower after a lapse of a seventh clock time from the opening direction control of the two-way valve, and simultaneously controlling the two-way valve in the closing direction . In things
is there. According to the cooling start control device for a refrigerant heating type air conditioner according to the fourth aspect, the two-way valve at the inlet of the heater is controlled in the opening direction.
Then, the refrigerant at the time of starting the cooling operation is recirculated at the time of using the heating operation.
Return to the variable frequency compressor through the
Hot gas cooling to variable frequency compressor even when using long piping
The medium will return. That is, from the variable frequency compressor
Returned refrigerant and oil to variable frequency compressor
It prevents abnormal pressure drop and oil drop of the frequency compressor.
Wear. In addition, hot gas is added to the liquid bag at the time of startup.
To prevent liquid backing, and highly reliable start-up control
Can be. In addition, the circuit for heating operation is used.
This eliminates the need for a cooling-dedicated bypass circuit. In addition, by activating the variable frequency compressor, and after a predetermined time has elapsed, by controlling the outdoor blower to operate, before operating the outdoor blower, the compressed air remains compressed by the variable frequency compressor. Since the hot gas passes through the heater and directly enters the variable frequency compressor, the liquid bag can be avoided by supplying the hot gas to the liquid back state at the time of starting the variable frequency compressor and reheating the liquid gas.

[0017]

Embodiment

First Embodiment FIGS. 1 to 3 show a first embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 shows a refrigeration cycle of a refrigerant-heated air conditioner, which is composed of a refrigeration cycle capable of cooling operation and a refrigeration cycle capable of heating operation.

The refrigeration cycle capable of cooling operation includes a variable frequency compressor 1, a four-way valve 10, an outdoor heat exchanger 5, a first pressure reducer 6a, a first check valve 7a, a second pressure reducer 6b, The indoor heat exchanger 2 and the second check valve 7b are connected in a ring shape. In addition, the refrigeration cycle capable of performing the heating operation is configured by connecting the variable frequency compressor 1, the four-way valve 10, the indoor heat exchanger 2, the third check valve 7c, the two-way valve 3, and the heater 4 in a ring shape. .

In FIG. 1, reference numeral 8 denotes an indoor unit main body;
Is an outdoor unit main body, 11a is a compressor temperature thermistor, 11b
Is an outside air temperature thermistor, and 15 is an outdoor unit blower. Further, the flow of the refrigerant in the normal cooling operation is shown by a solid line, and the flow of the refrigerant in the bypass control by the two-way valve 3 at the time of startup is shown by a broken line. FIG. 2 shows a control circuit device of a refrigerant heating type air conditioner. Reference numeral 12 denotes a microcomputer serving as control means, which includes a cooling start signal, a compressor temperature thermistor 11a,
The signal of the outside air temperature thermistor 11b is input. Here, the cooling start signal is a signal from an indoor unit or an outdoor unit, or a signal from the switch 22. 14a is a compressor temperature comparison unit that compares the temperature detected by the compressor temperature thermistor 11a with the set temperature, and 14b is the outside air that compares the temperature detected by the outside air temperature thermistor 11b with the set temperature. This is a temperature comparison unit.

The output of the control circuit device includes a microcomputer 1
2, a driving unit 16 that outputs a signal to drive the variable frequency compressor 1. Also, a signal is output from the microcomputer 12 to energize the relay coil 20 of the two-way valve 3,
0a is input to turn on the two-way valve 3. Further, a signal is output from the microcomputer 12, the relay coil 21 is energized, the contact 21a is turned on, and the outdoor unit blower 15 is turned on. In addition, 17 is an amplifier, 18 is a power supply, and 19 is a power switch.

FIG. 3 shows a control operation diagram, the operation of which will be described below. First, the microcomputer 12 sets the switch 22
Receives more cooling start signal, it starts the cooling operation (step S _11). Next, the variable frequency compressor 1 is turned on and operates at the set operating frequency (step
S _12). After the variable frequency compressor 1 is operated, the microcomputer
12 to wait until the first clock time T ₁ has elapsed
(Step S _13). Next, T ₁ after the first clock time,
It controls the two-way valve 3 in the opening direction (step S _14). Two-way valve
After the opening direction of 3 is controlled, the second clock time T ₂ elapses.
To wait until the (step S _15). Next, the second clock
After between T ₂ has elapsed, it controls the two-way valve 3 in the closing direction (step
S _16).

According to the cooling start control device for a refrigerant heating type air conditioner constructed as described above, when the two-way valve 3 at the inlet of the heater 4 is controlled to open, the refrigerant at the time of starting the cooling operation becomes
By returning to the variable frequency compressor 1 through the circuit at the time of using the heating operation, the hot gas refrigerant returns to the variable frequency compressor 1 even if the connection pipe is a long pipe. That is, the refrigerant and the oil that have flowed out of the variable frequency compressor 1 are quickly returned to the variable frequency compressor 1, and the abnormal pressure drop and the oil drop of the variable frequency compressor 1 can be prevented. In addition, by adding hot gas to the liquid bag at the time of starting, the liquid bag can be avoided, and highly reliable start control can be performed. In this way, long pipes and multiple refrigerants can be handled, and the reliability of the variable frequency compressor 1 can be ensured.

Also, since a circuit for heating operation is used, a bypass circuit dedicated to cooling is not required, and the structure is simple at low cost. Furthermore, the opening direction of the two-way valve 3 can be controlled.
By delaying the start of the variable frequency compressor 1, the variable frequency
When the compressor 1 is started, the refrigerant does not change suddenly,
Start-up control that does not apply excessive load to the frequency compressor 1
And highly reliable startup control can be realized. Also, at a predetermined time
After a lapse of time, by performing the closing direction control of the two-way valve 3,
Variable frequency compressor with minimum cooling capacity reduction
It is possible to minimize the generation of sound from No. 1.

FIG . 4 shows another control operation diagram.
The operation will be described below. First, the microcomputer 12 is switched.
A cooling start signal is received from the switch 22 and the cooling operation is started.
(Step S ₁ ). Next, the variable frequency compressor 1
on, and operate at the set operation frequency (step
Flop S _2). Simultaneously when variable frequency compressor 1 is turned on
Then, the two-way valve 3 is turned on and controlled in the opening direction (step
Flop S _3). It is also possible to control in this way,
The fourth to fourth embodiments have this operation.

[0025]

[0026] A second embodiment of the second embodiment the present invention, FIG. 1, FIG. 2 will be described with reference to FIG. FIG. 5 shows a control operation diagram, and the operation will be described below. First, microcomputer 1
2 receives the cooling start signal from the switch 22, start the cooling operation (step S _21). Then, for detecting the temperature Ta of the variable frequency compressor 1 by the compressor temperature thermistor 11a (step S _22). Next, variable frequency compressor 1 becomes on, operated at a set operating frequency (step S _23). At the same time, it controls the two-way valve 3 in the opening direction (step S _24). Then, after the two-way valve 3 is opened direction control compares the temperature Ta detected by the compressor temperature thermistor 11a, and a temperature To that is set in the temperature setting section (step S _25). As a result of the comparison, the compressor temperature thermistor 11
If the detected temperature Ta is low, the third clock time T
₃ and waits until the expiration of (step S _26). afterwards,
After the third clock time T _3, and controls the two-way valve 3 in the closing direction (step S _27). As a result of the comparison, if the temperature Ta detected by the compressor temperature thermistor 11a is high,
Waits until the expiration of the third long fourth clock time T ₄ from the clock time T ₃ (step S _28). Then, after the fourth clock time T _4, controls the two-way valve 3 in the closing direction (step S _29).

In the cooling start control device for a refrigerant-heated air conditioner thus configured , the first embodiment differs from the first embodiment.
At the same time as the variable frequency compressor 1 was turned on,
The difference is that the two-way valve 3 is turned on and controlled in the opening direction.
However, otherwise, the same effects as in the first embodiment are obtained. Further, the control time of the two-way valve 3 is controlled by detecting the temperature of the variable frequency compressor 1, and it is determined whether the startup control of the variable frequency compressor 1 is cold or hot. Since the back amount is reduced, the opening time of the two-way valve 3 is shortened,
If it is hot, the amount of liquid back increases, so the opening time of the two-way valve 3 is increased. That is, the variable frequency compressor 1
The amount of liquid back to the variable frequency compressor 1 is determined based on the temperature of the variable frequency compressor 1 and the bypass time is changed.
Thus, it is possible to accurately prevent the refrigerant from accumulating due to the heat radiation action of the outdoor heat exchanger due to the operation described above, to ensure the reliability of the variable frequency compressor 1, and to realize efficient two-way valve control.

The third embodiment of the third embodiment of the present invention, FIG. 1, FIG. 2, will be described with reference to FIG. FIG. 6 shows a control operation diagram, and the operation will be described below. First, the microcomputer 12
There receives the cooling start signal from the switch 22, start the cooling operation (step S _31). Next, the temperature Tb of the outside air temperature is detected by the outside air temperature thermistor 11b (step _S32 ). Next, the variable frequency compressor 1 is turned on, and operates at the set operation frequency (step _S33 ). At the same time, the two-way valve 3 is controlled to open (step _S34 ). Then, after the two-way valve 3 is opened direction control compares the temperature Tb detected by the outside air temperature thermistor 11b, and the temperature To 'that is set in the temperature setting section (step S _35). As a result of the comparison, if the temperature Tb detected by the outside air temperature thermistor 11b is high, the process stands by until the _fifth clock time T5 has elapsed (step _S36 ). Then, the fifth clock time T
After elapse of ₅ , the two-way valve 3 is controlled to close (step S
37). Also, as a result of the comparison, the outside air temperature thermistor 11b
A low in the detected temperature Tb is the fifth clock time T ₅
Waits until the elapsed clock time T ₆ of the longer sixth (step S _38). Then, after the sixth clock time T _6, and controls the two-way valve 3 in the closing direction (step S _39).

In the cooling start control device for a refrigerant-heated air conditioner having the above-described configuration , the first embodiment is different from the first embodiment.
At the same time as the variable frequency compressor 1 was turned on,
The difference is that the two-way valve 3 is turned on and controlled in the opening direction.
However, otherwise, the same effects as in the first embodiment are obtained. Further, by controlling the control time of the two-way valve 3 by detecting the outside air temperature, it is determined whether the liquid refrigerant easily accumulates in the outdoor unit,
If the outside air temperature is low, the opening time of the two-way valve 3 is extended,
If the outside air temperature is high, the time in the opening direction of the two-way valve 3 is shortened. That is, by judging the amount of liquid back due to the amount of accumulated refrigerant in the outdoor heat exchanger at the outside air temperature and changing the bypass time, liquid back is properly avoided, and the reliability of the variable frequency compressor 1 is improved. As a result, efficient two-way valve control can be realized.

The fourth embodiment of the fourth embodiment of the present invention, FIG. 1, FIG. 2 will be described with reference to FIG. FIG. 7 shows a control operation diagram, and the operation will be described below. First, the microcomputer 12
Receives the cooling start signal from the switch 22, and starts the cooling operation (step _S41 ). Next, the variable frequency compressor 1 is turned on, and operates at the set operation frequency (step _S42 ). At the same time, it controls the two-way valve 3 in the opening direction (step S _43). Next, after the two-way valve 3 is controlled to open, the process waits until the _seventh clock time T7 has elapsed (step _S44 ). Next, the seventh clock time T ₇ after the elapse of,
The outdoor blower 15 is operated (step _S45 ). Thereafter, the two-way valve 3 is controlled to close (step _S46 ).

In the cooling start control device for a refrigerant-heated air conditioner thus configured , the first embodiment differs from the first embodiment.
At the same time as the variable frequency compressor 1 was turned on,
The difference is that the two-way valve 3 is turned on and controlled in the opening direction.
However, otherwise, the same effects as in the first embodiment are obtained. Further, by starting the variable frequency compressor 1 and controlling the outdoor blower to operate after a predetermined time has elapsed, the compressor is compressed by the variable frequency compressor 1 before the outdoor blower 15 is operated. Since the hot gas as it is passes directly through the heater 4 and directly enters the variable frequency compressor 1, the hot gas is supplied to the liquid back state at the start of the variable frequency compressor 1 and reheated to avoid liquid back. it can.

[0032]

According to the cooling start control device for a refrigerant heating type air conditioner of the present invention, when the two-way valve at the inlet of the heater is controlled in the opening direction, the refrigerant at the time of starting the cooling operation is used during the heating operation. Returning to the variable frequency compressor through the circuit described above, the hot gas refrigerant returns to the variable frequency compressor even if the connection pipe is a long pipe. That is, the refrigerant and oil that have flowed out of the variable frequency compressor are quickly returned to the variable frequency compressor, and abnormal pressure drop and oil drop of the variable frequency compressor can be prevented. In addition, by adding hot gas to the liquid bag at the time of starting, the liquid bag can be avoided, and highly reliable start control can be performed. Furthermore, since a circuit for heating operation is used, a bypass circuit dedicated to cooling is not required. Ma
The opening direction of the two-way valve is controlled by starting the variable frequency compressor.
By delaying, when the variable frequency compressor starts,
No excessive load is applied to the variable frequency compressor without causing
Start control that is not possible and realizes highly reliable start control.
Wear. After a lapse of a predetermined time, the closing direction of the two-way valve is controlled.
Control to minimize cooling capacity degradation, and
Minimizing sound generation from variable frequency compressors
it can.

[0033]

[0034] According to the cooling start control apparatus according to claim 2 refrigerant heating type air conditioner according, the two-way valve of the heater inlet opening direction
When the cooling operation is started, the refrigerant at the time of starting the cooling operation uses the heating operation.
Return to the variable frequency compressor through the circuit of the time, the connection
Hot to variable frequency compressor even if long piping is used
The gas refrigerant will return. That is, variable frequency compression
Quickly returns refrigerant and oil from the compressor to the variable frequency compressor
To prevent abnormal pressure drop and oil drop of the variable frequency compressor
be able to. Also, hot against liquid back at startup
By adding gas, liquid back can be avoided and high reliability
Startup control is possible. In addition, use the circuit for heating operation.
This eliminates the need for a cooling-only bypass circuit. Ma
In addition, the temperature of the variable frequency compressor is detected to control the control time of the two-way valve, and it is determined whether the startup control of the variable frequency compressor is cold or hot. The opening direction time of the two-way valve is shortened because the number is reduced, and the opening time of the two-way valve is increased because the amount of liquid back increases when hot. That is, by determining the amount of liquid back to the variable frequency compressor based on the temperature of the variable frequency compressor and changing the bypass time, the refrigerant is accumulated by the heat radiation action of the outdoor heat exchanger due to the operation of the variable frequency compressor. , The reliability of the variable frequency compressor can be ensured, and efficient two-way valve control can be realized.

According to the third aspect of the present invention, the two-way valve at the inlet of the heater is opened in the opening direction.
When the cooling operation is started, the refrigerant at the time of starting the cooling operation uses the heating operation.
Return to the variable frequency compressor through the circuit of the time, the connection
Hot to variable frequency compressor even if long piping is used
The gas refrigerant will return. That is, variable frequency compression
Quickly returns refrigerant and oil from the compressor to the variable frequency compressor
To prevent abnormal pressure drop and oil drop of the variable frequency compressor
be able to. Also, hot against liquid back at startup
By adding gas, liquid back can be avoided and high reliability
Startup control is possible. In addition, use the circuit for heating operation.
This eliminates the need for a cooling-only bypass circuit. Ma
Also, by controlling the control time of the two-way valve by detecting the outside air temperature, it is determined whether or not the liquid refrigerant easily accumulates in the outdoor unit.If the outside air temperature is low, the time in the opening direction of the two-way valve is extended, and the outside air temperature is increased. The higher the temperature, the shorter the opening time of the two-way valve. That is, by judging the amount of liquid back due to the amount of accumulated refrigerant in the outdoor heat exchanger at the outside air temperature and changing the bypass time, liquid back is properly avoided and the reliability of the variable frequency compressor is secured. And efficient two-way valve control can be realized.

According to the fourth aspect of the present invention, the two-way valve at the inlet of the heater is opened in the opening direction.
When the cooling operation is started, the refrigerant at the time of starting the cooling operation uses the heating operation.
Return to the variable frequency compressor through the circuit of the time, the connection
Hot to variable frequency compressor even if long piping is used
The gas refrigerant will return. That is, variable frequency compression
Quickly returns refrigerant and oil from the compressor to the variable frequency compressor
To prevent abnormal pressure drop and oil drop of the variable frequency compressor
be able to. Also, hot against liquid back at startup
By adding gas, liquid back can be avoided and high reliability
Startup control is possible. In addition, use the circuit for heating operation.
This eliminates the need for a cooling-only bypass circuit. Ma
Also, by activating the variable frequency compressor and after a predetermined time has elapsed, by controlling the outdoor blower to operate,
Before the outdoor blower is operated, the hot gas compressed by the variable frequency compressor passes through the heater and directly enters the variable frequency compressor, so that the hot gas enters the liquid back state when the variable frequency compressor starts up. Liquid back can be avoided by supplying gas and reheating.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a refrigeration cycle of a refrigerant-heated air conditioner according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a cooling start control device for the refrigerant-heated air conditioner according to the embodiment of the present invention.

FIG. 3 is a flowchart illustrating a control operation of the refrigerant-heated air conditioner according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing another control operation in the embodiment of the present invention.

FIG. 5 is a flowchart illustrating a control operation of the refrigerant-heated air conditioner according to the second embodiment of the present invention.

FIG. 6 is a flowchart illustrating a control operation of the refrigerant-heated air conditioner according to the third embodiment of the present invention.

FIG. 7 is a flowchart illustrating a control operation of a refrigerant-heated air conditioner according to a fourth embodiment of the present invention.

FIG. 8 is a schematic diagram showing a refrigeration cycle of a conventional refrigerant-heated air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Variable frequency compressor 2 Indoor heat exchanger 3 Two-way valve 4 Heater 5 Outdoor heat exchanger 6 Pressure reducer 7 Check valve 8 Indoor unit main body 9 Outdoor unit main body 10 Four-way valve 11a Compressor temperature thermistor 11b Outside air temperature Thermistor 12 Microcomputer (control means) 15 Outdoor blower

Continuation of the front page (72) Inventor Shinichi Sato 1006 Kazuma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (56) References JP-A-7-35432 (JP, A) (58) Fields investigated ( Int.Cl. ⁷ , DB name) F25B 13/00

Claims (4)

(57) [Claims] 1. A variable frequency compressor, a four-way valve, an outdoor heat exchanger, a first decompressor, a first check valve, a second decompressor, an indoor heat exchanger, the four-way valve, a second A refrigeration cycle in which the check valve and the variable frequency compressor are connected in a ring in this order in order to perform a cooling operation; and the variable frequency compressor, the four-way valve, the indoor heat exchanger, and the second pressure reducer. A third check valve connected in parallel with
Two-way valve, the heater, the variable frequency compressor starts and the heating operation can refrigerant heating type refrigeration cycle formed by connecting in a ring in this order, the variable frequency compressor and to receive a cooling start signal, the variable frequency The first clock time elapsed from the start of the compressor
After passing, the two-way valve is controlled to open, and the two-way valve is controlled to open.
After a lapse of the second clock time from the control, the two-way valve is controlled to close.
Cooling activation control apparatus of the refrigerant heating type air conditioner and a control means for control. 2. A variable frequency compressor, a four-way valve, an outdoor heat exchanger, a first decompressor, a first check valve, a second decompressor, an indoor heat exchanger, the four-way valve, a second A refrigeration cycle in which the check valve and the variable frequency compressor are connected in a ring in this order in order to perform a cooling operation; and the variable frequency compressor, the four-way valve, the indoor heat exchanger, and the second pressure reducer. A third check valve connected in parallel with
A refrigerant-heated refrigeration cycle capable of heating operation in which a two-way valve, a heater, and the variable frequency compressor are connected in a ring in this order; and a variable frequency compressor is activated upon receiving a cooling start signal. controls way valve in the opening direction, the variable frequency
When the detected temperature of the compressor is less than the first set temperature,
After the elapse of the clock time of 3, the two-way valve is controlled to close,
The detected temperature of the variable frequency compressor is equal to or higher than the first set temperature.
Sometimes the fourth clock time longer than the third clock time
And a control means for controlling the two-way valve in a closing direction after a lapse of time. 3. A variable frequency compressor, a four-way valve, an outdoor heat exchanger, a first decompressor, a first check valve, a second decompressor, an indoor heat exchanger, the four-way valve, a second A refrigeration cycle in which the check valve and the variable frequency compressor are connected in a ring in this order in order to perform a cooling operation; and the variable frequency compressor, the four-way valve, the indoor heat exchanger, and the second pressure reducer. A third check valve connected in parallel with
A refrigerant-heated refrigeration cycle capable of heating operation in which a two-way valve, a heater, and the variable frequency compressor are connected in a ring in this order; and a variable frequency compressor is activated upon receiving a cooling start signal. Control the valve in the opening direction, and
When the temperature is higher than the set temperature of 2, after the elapse of the fifth clock time,
The two-way valve is controlled in the closing direction, and the outside air temperature is controlled to the second setting.
When the temperature is equal to or lower than the constant temperature, the sixth clock longer than the fifth clock time is used.
Control means for controlling the two-way valve in the closing direction after the elapse of the clock time . 4. A variable frequency compressor, a four-way valve, an outdoor heat exchanger, a first decompressor, a first check valve, a second decompressor, an indoor heat exchanger, the four-way valve, a second A refrigeration cycle in which the check valve and the variable frequency compressor are connected in a ring in this order in order to perform a cooling operation; and the variable frequency compressor, the four-way valve, the indoor heat exchanger, and the second pressure reducer. A third check valve connected in parallel with
A refrigerant-heated refrigeration cycle capable of heating operation in which a two-way valve, a heater, and the variable frequency compressor are connected in a ring in this order; and a variable frequency compressor is activated upon receiving a cooling start signal. Control the one-way valve in the opening direction and open the two-way valve.
After the elapse of the seventh clock time from the direction control, the outdoor blower is started
And a control means for simultaneously controlling the two-way valve in the closing direction .