JPH0510624A - Air conditioner - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the time from the start of a heating operation command until the actual blowing of warm air. A means for stopping the operation of the refrigerant heater 9 when the refrigerant temperature Teo detected by the refrigerant temperature sensor 22 becomes equal to or higher than the set temperature Teo1 and restarting the operation of the refrigerant heater when the refrigerant temperature Teo becomes lower than the set temperature Teo1. , The refrigerant temperature Teo detected by the refrigerant temperature sensor 22 is the set temperature Teo1
A means for counting the number n of times the temperature has changed from the smaller state to the set temperature Teo1 or more, and after the number of times n exceeds the set number, the operating frequency of the compressor 1 is increased by one step from the maximum frequency FN set in the heating operation. And means for driving.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner equipped with a refrigerant heater.

[0002]

2. Description of the Related Art FIG. 1 shows an air conditioner refrigeration system that includes a heat pump type refrigeration cycle and a refrigerant heater, and combines the heat pumping action of the heat pump type refrigeration cycle and the refrigerant heating action of the refrigerant heater to heat the room. It is a block diagram which shows a cycle. In FIG. 1, a variable capacity compressor 1, a four-way valve 2, an outdoor heat exchanger 3, a check valve 4 (forward direction), a pressure reducer such as an electric expansion valve 5, an indoor heat exchanger 6, the four-way valve 2, Further, the check valve 7 (forward direction) is sequentially connected to form a heat pump type refrigeration cycle. The two-way valve 8 is connected from the communication portion between the check valve 4 and the expansion valve 5 to the suction port of the compressor 1.
And the refrigerant heater 9 are sequentially connected.

The refrigerant heater 9 is equipped with a gas burner 10 as an accessory, and the gas burner 10 is connected to a fuel supply source (not shown) via a proportional valve 11 and a two-way valve 11a. .. It should be noted that the outdoor fan 12 is provided near the outdoor heat exchanger 3.
And an indoor fan 13 is provided near the indoor heat exchanger 6.

Further, 21 is a first refrigerant temperature sensor for detecting the refrigerant temperature Tei at the inlet of the refrigerant heater 9, 22 is a second refrigerant temperature sensor for detecting the refrigerant temperature Teo at the outlet of the refrigerant heater 9, and 23. Is an indoor heat exchanger sensor for detecting the temperature Tc of the indoor heat exchanger 6.

In the air conditioner having the refrigeration cycle shown in FIG. 1, the compressor 1 is operated, the four-way valve 2 is switched, the two-way valve 8 is opened, and the refrigerant heater 9 is operated (gas burner 1
(Combustion of 0) is set, and the refrigerant discharged from the compressor 1 is passed through the four-way valve 2, the indoor heat exchanger 6, the external heat exchanger 3, the check valve 4, the electric expansion valve 5, and the two-way valve 8. Pour into the heater 9,
The refrigerant that has passed through the refrigerant heater 9 is returned to the compressor 1 through the four-way valve 2 and the heating operation is executed. Then, during this heating operation, the difference between the set temperature of the remote controller (not shown) and the room temperature is obtained as the heating load, and the operating frequency of the compressor 1 (the output frequency of the inverter circuit) is controlled according to the heating load.

Further, during the heating operation, the detected temperature Teo of the second refrigerant temperature sensor 22 is the set value T for preventing the excessive temperature rise.
When it exceeds eo1, the two-way valve 11a is closed to stop the heating of the refrigerant heater 9 (combustion of the gas burner 10), and the detected temperature Teo of the second refrigerant temperature sensor 22 is set value T for preventing overheating.
When it falls below eo1, control is performed to open the two-way valve 11a and restart heating of the refrigerant heater 9 (combustion of the gas burner 10).

[0007]

By the way, when the outside air temperature is low, the operating frequency of the compressor 1 is increased step by step from the start of heating as shown in FIG. 5, and at the maximum frequency FN set during heating operation. You will be driven.
However, since the predetermined refrigerant circulation amount cannot be obtained even if the operating frequency of the compressor 1 is operated at the maximum frequency FN, the detected temperature Teo of the second refrigerant temperature sensor 22 exceeds the set value Teo1 for preventing excessive temperature rise. The two-way valve 11a is controlled to be closed, and the heating of the refrigerant heater 9 (combustion of the gas burner 10) is stopped. Heating of the refrigerant heater 9 (combustion of the gas burner 10)
The temperature Teo detected by the second refrigerant temperature sensor 22 falls below the set value Teo1 for preventing overheating, and the two-way valve 11a is controlled to be closed to heat the refrigerant heater 9 (of the gas burner 10). Combustion) is restarted.

Since such control is repeatedly performed,
As shown in FIG. 5, the time from the start of the heating operation until the temperature Tc of the indoor heat exchanger 6 rises to a set temperature Tco at which the operation of the indoor fan 13 is started and the control for blowing hot air is started. t1 was long.

The present invention has been made in view of the above points, and an object thereof is to provide an air conditioner capable of shortening the time from the start of a heating operation command to the blowing of warm air. Especially.

[0010]

The present invention relates to a heat pump type refrigeration cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an electric expansion valve, and an indoor heat exchanger communicate with each other, and the outdoor heat exchanger. A refrigerant heater provided so as to communicate from the communication portion of the electric expansion valve to the suction port of the compressor, and a four-way valve for discharging the refrigerant discharged from the compressor, an indoor heat exchanger, an electric expansion valve, a refrigerant heater Through which the refrigerant heater is driven to perform the heating operation, a refrigerant temperature sensor for detecting the refrigerant temperature Teo flowing out from the refrigerant heater, and an operating frequency of the compressor according to the heating load during the heating operation. When the refrigerant temperature detected by the refrigerant temperature sensor is equal to or higher than the set temperature Teo1, the operation of the refrigerant heater is stopped and the refrigerant temperature is set to the set temperature. Means for restarting the heating operation of the refrigerant heater when it becomes smaller than Teo1, means for counting the number n of times when the refrigerant temperature detected by the refrigerant temperature sensor has changed from a state smaller than the set temperature Teo1 to a set temperature Teo1 or more, After the number of times n exceeds the set number of times, the operating frequency of the compressor is increased by one step from the maximum frequency FN set during the heating operation, and the air conditioner is operated.

[0011]

[Operation] During heating operation, the operating frequency of the compressor is controlled to the maximum frequency FN according to the heating load, and the number of times the refrigerant temperature detected by the refrigerant temperature sensor is smaller than the set temperature Teo1 or has changed to the set temperature Teo1 or more. After n exceeds the set number of times, the operating frequency of the compressor is controlled to be increased by one step from the maximum frequency FN set in the heating operation. As a result, the required refrigerant circulation amount is secured, and the time from the start of the heating operation command to the actual blowing of warm air is shortened.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing a refrigeration cycle of an air conditioner that includes a heat pump type refrigeration cycle and a refrigerant heater, and combines the heat pumping action of the heat pump type refrigeration cycle and the refrigerant heating action of the refrigerant heater to heat the room. Is. In FIG. 1, a variable capacity compressor 1, a four-way valve 2, an outdoor heat exchanger 3, a check valve 4 (forward direction), a pressure reducer such as an electric expansion valve 5, an indoor heat exchanger 6, the four-way valve 2, Further, the check valve 7 (forward direction) is sequentially connected to form a heat pump type refrigeration cycle. The two-way valve 8 is connected from the communication portion between the check valve 4 and the expansion valve 5 to the suction port of the compressor 1.
And the refrigerant heater 9 are sequentially connected.

The refrigerant heater 9 is provided with a gas burner 10 as an accessory, and the gas burner 10 is connected to a fuel supply source (not shown) via a proportional valve 11 and a two-way valve 11a. .. An outdoor fan 12 is provided near the outdoor heat exchanger 3, and an indoor fan 13 is provided near the indoor heat exchanger 6.

Further, 21 is a first refrigerant temperature sensor for detecting the refrigerant temperature Tei at the inlet of the refrigerant heater 9, 22 is a second refrigerant temperature sensor for detecting the refrigerant temperature Teo at the outlet of the refrigerant heater 9, and 23. Is an indoor heat exchanger sensor for detecting the temperature Tc of the indoor heat exchanger 6. The control circuit is shown in FIG.
The power supply terminal of the indoor control unit 40 is connected to the commercial AC power supply 30, and the outdoor control unit 50 is connected to the power supply terminal of the indoor control unit 40 via the power supply line 31.

The indoor heat exchange temperature sensor 23, the indoor temperature sensor 41, the light receiving circuit 42, and the fan motor 13M of the indoor fan 13 are connected to the indoor control section 40. Light receiving circuit 42
Is to receive infrared light transmitted from a remote control type operation unit (hereinafter, abbreviated as remote controller) 43.

The outdoor control unit 50 includes a four-way valve 2, an electric expansion valve 5, two-way valves 8 and 14, a proportional valve 11 and a two-way valve 11.
a, the fan motor 12M of the outdoor fan 12, the first refrigerant temperature sensor 21, the second refrigerant temperature sensor 22, and the inverter circuit 51 are connected.

The inverter circuit 51 rectifies the AC voltage of the power supply line 31, converts it into an AC voltage of a frequency according to the command of the outdoor control unit 50, and outputs it. The compressor motor 1M of the variable capacity compressor 1 is connected to the output terminal of the inverter circuit 51. Then, the indoor control unit 40
The outdoor control unit 50 and the outdoor control unit 50 are connected to each other by a serial signal line 32 synchronized with the power supply voltage, and data transfer between them is enabled.

The indoor control unit 40 and the outdoor control unit 50 are
Each is composed of a microcomputer and its peripheral circuits, and controls the air conditioner in general. That is, the indoor control unit 40 and the outdoor control unit 5
0, the following functional means are provided.

(1) The operation of the compressor 1, the non-switching of the four-way valve 2, the closing of the two-way valve 8 and the operation of the refrigerant heater 9 are set to turn off the refrigerant discharged from the compressor 1 by the four-way valve. 2, it flows to the indoor heat exchanger 6 through the outdoor heat exchanger 3, the check valve 4, and the electric expansion valve 5, and the refrigerant passing through the indoor heat exchanger 6 is passed to the compressor 1 through the four-way valve 2 and the check valve 7. A means for returning and performing a cooling operation.

(2) During the cooling operation, the difference between the temperature detected by the indoor temperature sensor 41 and the set temperature of the remote controller 43 is obtained, and the operating frequency of the compressor 1 (the inverter circuit 5 is calculated according to the obtained difference).
Output frequency of 1).

(3) Operation of the compressor 1, switching of the four-way valve 2,
The opening of the two-way valve 8 and the operation of the refrigerant heater 9 (combustion of the gas burner 10) are set so that the refrigerant discharged from the compressor 1 is transferred to the four-way valve 2, the indoor heat exchanger 6, the outdoor heat exchanger 3, and the reverse. A means for causing a refrigerant heater 9 to flow through the stop valve 4, the electric expansion valve 5, and the two-way valve 8, returning the refrigerant passing through the refrigerant heater 9 to the compressor 1 through the four-way valve 2, and performing a heating operation.

(4) During heating operation, the difference between the temperature detected by the remote controller 43 and the temperature detected by the indoor temperature sensor 41 is obtained as a heating load, and the operating frequency of the compressor 1 (output of the inverter circuit 51 is determined according to the heating load. Frequency) in a range up to the maximum frequency FN set during heating operation. (5) During heating operation, the difference Δ between the detected temperature Teo of the second refrigerant temperature sensor 22 and the detected temperature Tei of the first refrigerant temperature sensor 21.
Calculation means for calculating T (= Teo-Tei).

(6) Temperature difference Δ calculated above during heating operation
T, that is, the degree of refrigerant superheat is set value ΔTsa (for example, 5 to 8 d
eg) means for controlling the opening degree of the electric expansion valve 5 so as to be constant.

(7) Second heating temperature sensor 2 during heating operation
When the detected temperature Teo of 2 becomes equal to or higher than the set value Teo1 for preventing overheating, the two-way valve 11a is closed to stop the heating of the refrigerant heater 9 (combustion of the gas burner 10), and the detection of the second refrigerant temperature sensor 22 is performed. Temperature Teo is set value Teo1 to prevent overheating.
When it becomes smaller, the two-way valve 11a is opened and the refrigerant heater 9 is opened.
Means for starting the heating operation (combustion of the gas burner 10).

(8) The second refrigerant temperature sensor 2 during the heating operation
A means for counting the number n of times when the refrigerant temperature Teo detected by 2 changes from the state where it is lower than the set temperature Teo1 to the set temperature Teo1 or higher.

(9) When the refrigerant temperature Teo detected by the second refrigerant temperature sensor 22 subsequently changes from the state smaller than the set temperature Teo1 to the set temperature Teo1 or more after the number of times n exceeds the set number of times, the compressor is A means for operating by increasing the operating frequency of 1 from the maximum frequency FN set in heating operation by one step. Next, the operation will be described. When the desired room temperature is set by the remote controller 43 and the heating operation is started, the detected temperature of the room temperature sensor 41 is first compared with the set room temperature.

If the temperature detected by the room temperature sensor 41 is lower than the set room temperature, the compressor 1 is started with the two-way valves 8 and 14 opened, the four-way valve 2 is switched, and the refrigerant heater is further activated. 9 heating operation (burning gas burner 10)
To do. Then, the refrigerant flows in the direction of the dashed arrow in FIG.
One heating cycle is formed, the indoor heat exchanger 6 functions as a condenser, and the refrigerant heater 9 functions as an evaporator.

During this heating operation, the difference between the set room temperature based on the operation of the remote controller 43 and the temperature detected by the room temperature sensor 41 is obtained as a heating load, and the operating frequency of the compressor 1 is controlled according to the heating load.

During the heating operation, the first refrigerant temperature sensor 2
The detected temperature Tei of 1 (the temperature of the refrigerant flowing into the refrigerant heater 9 through the expansion valve 5) is taken in, and the detected temperature Teo of the second refrigerant temperature sensor 22 (the temperature of the refrigerant flowing out of the refrigerant heater 9) is taken in. , Difference between both detected temperatures ΔT (= Teo-Tei)
To calculate. This temperature difference ΔT corresponds to the degree of refrigerant superheat in the refrigerant heater 9. Then, the temperature difference ΔT is the set value T
The opening degree of the electric expansion valve 5 is controlled so as to be constant at sa.

Further, considering the temperature difference ΔT and the heating amount control condition, if the temperature difference ΔT is less than the set value Ts2 (for example, 26 ° C.), the opening of the proportional valve 11 is adjusted according to the heating load. , The heating amount of the refrigerant heater 9 (combustion amount of the gas burner 10) is controlled.

When the heating operation is started in this way,
Flow chart processing as shown in FIG. 3 is performed. First,
The flag F and the counter C are cleared to zero (step S
1). This flag F indicates that the detected temperature Teo of the second refrigerant temperature sensor 22 is lower than the set temperature Teo1 from the set temperature Teo.
It is set to "1" when it changes to eo1 or more, and the counter C counts the number of times n.

Then, it is judged whether the detected temperature Teo of the second refrigerant temperature sensor 22 is equal to or higher than the set temperature Teo1 (step S2), and if "NO", the two-way valve 11a is opened and the refrigerant heater 9 is heated. (The gas burner 10 is burned) and the flag F is reset (step S3). In addition,
If the two-way valve 11a has already been opened, that state is maintained.

Due to the heating of the refrigerant heater 9, the outlet temperature Teo of the refrigerant heater 9 gradually rises. And time Ta
If so, it is determined to be "YES" in step S2, and if the flag F is not set to "1" (step S2).
4), it is determined whether the counter C is "1" (step S5).

Here, since the counter C remains "0", the counter C is incremented by 1, the counter C is set by "1", the flag F is set by "1", and the two-way valve 1
1a is controlled to open and the refrigerant heater 9 stops heating (gas bar).
The combustion of the engine 10 is stopped) (steps S6 and S7).

When the combustion of the gas burner 10 is stopped, the outlet temperature Teo of the refrigerant heater 9 drops. Then, after the time Tb, the determination in step S2 is "NO", the refrigerant heater 9 is heated (the gas burner 10 is burned), and the flag F is reset. As a result, the outlet temperature Teo of the refrigerant heater 9 rises after a while. When the detected temperature Teo of the second refrigerant temperature sensor 22 reaches the time Tc at which the set temperature Teo1 or more is reached again, it is determined to be "YES" in step S2, "NO" in step S4, and "YES" in step S5. The determined operating frequency of the compressor 1 is set to the maximum frequency FN + 1 step set in the heating operation (step S8). By increasing the operating frequency of the compressor 1 by one step from the maximum frequency FN set in the heating operation in this way, the refrigerant circulation amount can be secured, so that the outlet temperature Teo of the refrigerant heater 9 becomes equal to or higher than the set temperature Teo1. As a result, the combustion of the burner 10 is stopped and the time delay for the indoor heat exchange temperature Tc to rise can be eliminated. Therefore, the time t2 from when the heating is started until the indoor heat exchange temperature Tc becomes the temperature Tco and the indoor fan 13 is rotated and hot air is blown out can be made shorter than before.

It should be noted that the set temperature Teo is changed from the state where the detected temperature Teo of the second refrigerant temperature sensor 22 is smaller than the set temperature Teo1.
If the operating frequency of the compressor 1 is increased by 1 step from the maximum frequency FN after changing only once more than 1,
A flag may be used instead of the counter C.

[0037]

As described in detail above, according to the present invention, it is possible to provide an air conditioner capable of shortening the time from the start of a heating operation command until the warm air is blown out. ..

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a refrigeration cycle according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a control circuit of the same embodiment.

FIG. 3 is a flow chart for explaining the operation of the embodiment.

FIG. 4 is a timing chart for explaining the operation of the embodiment.

FIG. 5 is a timing chart for explaining the operation of the conventional example.

[Explanation of symbols]

1 ... Variable capacity compressor, 2 ... Four-way valve, 3 ... Outdoor heat exchanger,
5 ... Electric expansion valve, 6 ... Indoor heat exchanger, 8, 11a, 1
4 ... 2-way valve, 9 ... Refrigerant heater, 10 ... Gas burner, 21
... first refrigerant temperature sensor, 22 ... second refrigerant temperature sensor, 2
3 ... Outdoor temperature sensor, 40 ... Indoor control unit, 50 ... Outdoor control unit.

Claims (1)

Claim: What is claimed is: 1. A heat pump type refrigeration cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an electric expansion valve, and an indoor heat exchanger communicate with each other, and the outdoor heat exchanger and an electric motor. Refrigerant heater provided in communication from the communication section of the expansion valve to the suction port of the compressor, and the refrigerant discharged from the compressor through a four-way valve, an indoor heat exchanger, an electric expansion valve, and a refrigerant heater. A means for flowing the refrigerant heater to perform the heating operation, a refrigerant temperature sensor for detecting the refrigerant temperature Teo flowing out from the refrigerant heater, and an operating frequency of the compressor according to the heating load during the heating operation. When the refrigerant temperature detected by the means for controlling the maximum frequency FN set during the heating operation and the refrigerant temperature sensor becomes equal to or higher than the set temperature Teo1, the operation of the refrigerant heater is stopped and the refrigerant temperature is set to the set temperature To.
A means for restarting the heating operation of the refrigerant heater when it becomes smaller than eo1 and a state where the refrigerant temperature detected by the refrigerant temperature sensor is smaller than the set temperature Teo1 from the set temperature Teo
A means for counting the number of times n changed to 1 or more;
And a means for operating the compressor by increasing the operating frequency of the compressor by one step from the maximum frequency FN set during heating operation after the number exceeds the set number of times.