JPS634108B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a refrigerant removal operation in an air conditioner equipped with a refrigerant heater that improves heating capacity at low outside temperatures.

Conventional configuration and problems Generally, in this type of air conditioner, when the refrigerant is passed through the outdoor heat exchanger during refrigerant heating operation, heat is radiated due to the influence of the wind and outside temperature, reducing the heating capacity and reducing the outdoor heat. There are drawbacks such as the inability to stabilize the refrigeration cycle because refrigerant and oil accumulate in the exchanger. Therefore, conventionally, during heating operation, the refrigerant was not passed through the outdoor heat exchanger, and the refrigerant and oil accumulated in the outdoor heat exchanger were removed for a certain period of time at the start of refrigerant heating operation and stored in the indoor heat exchanger. , control is implemented to normalize the refrigeration cycle by keeping the amount of refrigerant and oil constant.
By the way, conventionally, if the room temperature detection device is lower than the set temperature, the refrigeration cycle is operated normally and refrigerant drain control is performed at the same time, but if the room temperature is higher than the set temperature, the refrigeration cycle operation and the refrigerant drain control are also stopped. However, in this case, if the room temperature changes during the refrigerant bleeding control and the room temperature becomes higher than the set temperature and the refrigerant bleeding control stops, the refrigerant will be drained again. Extraction control will be performed. When this happens, it takes time to start the refrigerant heating operation, resulting in a disadvantage that the start-up becomes slow.

Purpose of the Invention In order to solve the above-mentioned conventional drawbacks, the present invention ignores the room temperature detection device during the set time at the start of refrigerant heating operation, and performs refrigerant removal control by constantly operating the refrigeration cycle without detecting the room temperature. It was designed so that

Composition of the Invention In order to achieve the above object, the heating operation control device for an air conditioner according to the present invention includes a control device for controlling the refrigerant heating operation and the refrigerant removal operation, which detects the room temperature as shown in FIG. a detection means, an operation detection means for detecting that the refrigerant extraction operation is in progress, and a stop for stopping the temperature capture operation of the room temperature detection means until the refrigerant extraction operation is completed based on an operation detection signal of the operation detection means; and a control means that receives a signal from the room temperature detection means via the stop means and controls the operation of the compressor and refrigerant heater, and controls the room temperature to a predetermined high temperature during the refrigerant removal operation. Even if it reaches this point, the refrigerant draining operation is continued as it is, and the refrigerant draining operation is completed preferentially to maintain good start-up characteristics.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, 1 is a compressor, 2 is a four-way switching valve as a cooling/heating switching valve, 3 is an indoor heat exchanger, 4 is a pressure reducing device for cooling, 5 is a check valve that passes refrigerant during cooling, and 6
is an outdoor heat exchanger; 7 is a check valve; 8 is an on-off valve that changes the flow of refrigerant during heating operation, that is, during refrigerant heating operation and during cooling operation; 9 is heating the refrigerant bunched into the compressor 1; The vaporizing refrigerant heater 9 includes a heat medium 9a such as water and a heating device for heating the heat medium 9a. In this heating device, 15 is a combustion fan, 16 is a rotating plate, and 17 is a motor interlocked with the combustion fan 15 and the rotating plate 16. 18 is a pipe provided so that liquid fuel is sprayed on the rotary plate 16; 19 is an on-off valve that controls the supply of liquid fuel flowing through the pipe 18; 20 is an electric heater;
1 is a spark plug, and 22 is an exhaust port. 10 is an on-off valve that connects the discharge side and suction side of the compressor 1. 11 and 12 are an indoor blower and an outdoor blower, respectively. 23 is a room temperature detection device provided on the air suction side of the indoor heat exchanger 6. A refrigeration cycle is constructed by connecting these in a ring as shown in the figure. Here, 24 is a control device that controls the compressor 1, indoor blower 11, outdoor blower 12, four-way switching valve 2, on-off valves 8, 10, 19, combustion fan 17, spark plug 21, and electric heater 20, each with a relay. are connected as shown in FIG. That is, the compressor 1, four-way switching valve 2, on-off valves 8 and 10, indoor blower 11, outdoor blower 12, motor 17, on-off valve 19, electric heater 20, and spark plug 21 are relay contacts 1a, 2a, 8a, and 10a, respectively. ,11
a, 12a, 17a, 19a, 20a, and 21a, and these series circuits are connected in parallel to each other.

Further, the control device 24 includes a room temperature detection device 2 corresponding to room temperature detection means, as shown in FIG.
In addition to 3, there is also an operation detection means for detecting that the refrigerant extraction operation is in progress, and a stop for stopping the temperature capturing operation of the room temperature detection means until the refrigerant extraction operation is completed based on an operation detection signal of the operation detection means. means, a function of taking in the signal of the room temperature detection means via the stop means and controlling the operation of the compressor 1 and the refrigerant heater 9, and an output of the room temperature detection means when the stop means is not operating. The system is equipped with a control means having a function of controlling the operation of the compressor 1 and the refrigerant heater 9, and is realized by a microcomputer or the like.

In the above configuration, during cooling operation, the refrigerant discharged from the compressor 1 is transferred to the four-way switching valve 2, the outdoor heat exchanger 6, the check valve 5, the pressure reducer 4, the indoor heat exchanger 3, the four-way switching valve 2, A refrigeration cycle is configured in which the refrigeration cycle passes through the check valve 7 and returns to the compressor 1. Note that if the room temperature is lower than the set temperature, the contact of the room temperature detection device 23 is opened and the cooling operation is stopped.

Next, when performing a heating operation using the vaporization type refrigerant heater 9, that is, a refrigerant heating operation, the refrigerant is sent to the compressor 1, the four-way switching valve 2, the indoor heat exchanger 3, the on-off valve 8, and the vaporization type refrigerant heater 9. Two cycles are constructed: a refrigeration cycle in which the air flows into the compressor 1, and a refrigeration cycle in which the air flows from the compressor 1 through the on-off valve 10 to the compressor 1. However, in the case of refrigerant heating operation, the refrigerant does not pass through the outdoor heat exchanger 6 due to the check valves 5 and 7. Further, at the same time as the refrigerant heating operation, the heater 20 is energized until the temperature rises to a certain level or higher. Note that if the room temperature is higher than the set temperature, the contact of the room temperature detection device 23 is opened and the refrigerant heating operation is stopped.

Here, when starting the refrigerant heating operation using the evaporative refrigerant heater 9, in order to obtain a stable refrigeration cycle,
It is necessary to remove the refrigerant accumulated in the outdoor heat exchanger. This refrigerant removal is performed as follows. First, by closing the on-off valves 8 and 10 for a certain period of time, the refrigerant accumulated in the outdoor heat exchanger 6 passes through the four-way switching valve 2, the check valve 7, the compressor 1, and the four-way switching valve 2.
After passing through the indoor heat exchanger 3, the refrigerant does not flow any further due to the on-off valve 8 and the check valve 5, and eventually accumulates inside the indoor heat exchanger 3. In addition, the evaporative refrigerant heater 9
The refrigerant that had accumulated inside the indoor heat exchanger 3 similarly accumulates inside the indoor heat exchanger 3. After this refrigerant removal control is completed, the motor 17 rotates, and the combustion fan 15 and the rotating plate 16 are rotated.
rotates, the on-off valve 19 opens at the same time, and the liquid fuel flows from the pipe 18 to the rotary plate 16 and is stirred. When it becomes a mist, it is heated by the electric heater 20 and vaporized, and is ignited by the spark plug 21. be done.

By the way, within a certain period of time during this refrigerant removal control, the room temperature detection device 23 is ignored and the control device 24 forcibly performs the refrigerant removal control.

Specifically, as shown in FIG. 4, when the refrigerant extraction operation is started (step 2) while the indoor temperature t is being captured (step 1), the capture of the indoor temperature t is stopped (step 3), The on-off valves 8 and 10 are closed to perform refrigerant removal operation (step 4). Then, the set time T is measured (step 5), and when the set time T has elapsed (step 6), the indoor temperature is taken in again (step 1), and the refrigerant heating operation (step 7) starts from step 2. The control device 24 operates to continue until the refrigerant removal operation is performed again.

In this manner, the control device 24 ignores the room temperature detection device 23 during the refrigerant removal control, so that the refrigerant removal control can be performed regardless of changes in the room temperature.
Therefore, the refrigerant heating operation can be performed at the time when the refrigerant extraction control is completed, so that stable refrigeration cycle operation can be performed because the start-up characteristics are good and the refrigerant extraction is not performed many times.

Effects of the Invention As is clear from the description of the embodiments above, the heating operation control device for an air conditioner of the present invention detects the indoor temperature during the operation of removing refrigerant from the outdoor heat exchanger during heating. The room temperature detection device that controls the operation and stop of the refrigeration cycle detects the room temperature and forces the refrigeration cycle to operate even if the control mode is set to stop, thereby controlling refrigerant removal even if the room temperature becomes high during refrigerant removal. to continue a stable refrigeration cycle. Furthermore, since the time between refrigerant removal control is shortened, there are effects such as good start-up performance and improved feeling.

[Brief explanation of the drawing]

Fig. 1 is a refrigeration cycle diagram of an air conditioner equipped with a heating operation control device according to an embodiment of the present invention, Fig. 2 is a partial electrical circuit diagram of the air conditioner, and Fig. 3 is a heating operation according to the present invention. FIG. 4 is a block diagram representing the control device using function realizing means, and is a flowchart for explaining the operation of the control device in this embodiment. 1... Compressor, 2... Four-way switching valve, 3... Indoor heat exchanger, 4... Cooling pressure reducing device, 5... Check valve, 6... Outdoor heat exchanger, 7... Check valve , 8...
Opening/closing valve, 9... vaporizing refrigerant heater, 23... room temperature detection device.

Claims (1)

[Claims] 1 A refrigeration cycle is constructed by connecting a compressor, a heating/cooling switching valve, an outdoor heat exchanger that acts as a condenser during cooling, a pressure reducing device, and an indoor heat exchanger that acts as an evaporator during cooling and a radiator during heating. Further, this refrigeration cycle is provided with a refrigerant heater having one end connected between the indoor heat exchanger and the pressure reducing device via an on-off valve, and the other end connected to the suction side of the compressor, and further When the indoor temperature falls below a set temperature, the opening/closing valve is opened to allow the refrigerant from the indoor heat exchanger to flow to the refrigerant heater and the refrigerant heating operation is heated there, and the cooling/heating switching valve is switched. A control device is provided for controlling a refrigerant extraction operation in which the on-off valve is closed to cause the refrigerant discharged from the compressor to flow from the outdoor heat exchanger to the indoor heat exchanger, and the refrigerant is stored in the indoor heat exchanger, and the control device A room temperature detection means detects the room temperature, an operation detection means detects that the refrigerant extraction operation is in progress, and an operation detection signal of the operation detection means causes the room temperature detection means to operate until the refrigerant extraction operation is completed. stopping means for stopping the temperature capturing operation and canceling the temperature capturing stop of the room temperature detecting means in response to a failure detection signal; capturing the room temperature detection signal via the stopping means;
A heating operation control device for an air conditioner, comprising a control means for operating the compressor when the room temperature is below a set value, and operating the refrigerant heater and the compressor after the refrigerant extraction operation is completed.