JPH109725A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a feeling of cold air due to simultaneous defrosting of two cycles and ensure reliability of a heating operation cycle during one machine heating operation by preventing, when one unit of or one air conditioner starts defrosting operation, the other air conditioner from entering defrosting operation. SOLUTION: An indoor fan 6 and an indoor fan 7 corresponding to an indoor heat exchanger 2 and an indoor heat exchanger 3 in an indoor unit 1 are mounted over the entire surface of each indoor heat exchanger, and are connected with indoor electric boxes 4, 5. Hereby, a defrosting control signal outputted from outdoor units 8, 9 connected with the indoor electric boxes is received to individually control the indoor fans 6, 7 and hence ensure air amount control of the indoor fan in response to conditions. Further, an outdoor electric box 10 and an outdoor electric box 11 are connected with each other through a transmission line to exchange information such as defrosting operation information whereby control is ensured to prevent simultaneous defrosting operation from being started.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an air conditioner.

[0002]

2. Description of the Related Art Conventional technology is disclosed in Hitachi Review, Vol. 77,
No. 886, November 1995, page 9, single outdoor unit combined with one indoor unit, single outdoor unit combined with multiple indoor units Multi-machines are common.

[0003]

The problem to be solved by the present invention is that an indoor unit has two independent heat exchangers and a blower, and an outdoor unit corresponding to each heat exchanger is connected. Is about.

When the two outdoor units start defrosting at the same time, the air is cooled by the evaporative action of the heat exchanger in the indoor unit, giving a sense of cool air to a person in the room.

When one cycle in the indoor unit is operated for heating and one cycle is operated for defrosting, and two blowers in the indoor unit are controlled by one electric motor, the two blowers are driven by a weak wind. Need to run or stop. At this time, the condensing pressure of the cycle during the heating operation increases, which causes heating of the electric motor in the compressor and further deterioration of the refrigerating machine oil, which causes a failure of the compressor.

An object of the present invention is to prevent a feeling of cool air by simultaneous defrosting of two cycles, and to ensure the reliability of a heating operation cycle during one defrosting operation and one heating operation.

[0007]

According to the present invention, an indoor electric box 4 for controlling an indoor blower 6 and an indoor electric box 5 for controlling an indoor blower 7 are mounted on an indoor unit.

Further, the outdoor electric box 10 and the outdoor electric box 11 are connected by a transmission line and control signals are exchanged, so that the outdoor unit performing the defrosting operation and the outdoor unit performing the heating operation are distinguished, and the defrosting operation is performed. The control signal is sent from the outdoor unit to the electric box of the indoor unit performing the defrosting operation, and only the blower on the side performing the defrosting operation controls the air volume.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

The indoor unit 1 developed in the present invention has an indoor heat exchanger 2 and an indoor heat exchanger 3 having independent cycle paths mounted on a common base, and an outdoor unit 8 and an outdoor unit 8 corresponding to each indoor heat exchanger. Connect to outdoor unit 9.
Accordingly, by performing the capacity control and the start / stop control of the outdoor unit, it becomes possible to cope with various operating conditions. Further, the capacity control of the indoor unit 1 can be easily performed only by the start / stop control of the outdoor unit.

The indoor heat exchanger 2 in the indoor unit 1
The indoor blower 6 and the indoor blower 7 corresponding to the indoor heat exchanger 3 are attached to the front of each indoor heat exchanger, and the indoor electric boxes 4 and 5 are connected to each other. The defrost control signals output from the connected outdoor unit 8 and the outdoor unit 9 are received, and the indoor blower 6 and the indoor blower 7 can be individually controlled,
It became possible to control the air volume of the indoor blower according to the situation.

Also, the outdoor unit electric box 10 and the outdoor unit electric box 1
1 is connected by a transmission line, and by exchanging information such as defrosting operation information, it has become possible to control not to enter the defrosting operation at the same time.

FIG. 2 shows a flowchart of the main defrost control.

After the start of the heating operation, if the defrosting start condition is satisfied according to the time condition such as the accumulated time of the heating operation and the temperature condition such as the outside air temperature and the pipe temperature, the outdoor unit enters the defrosting preparation control. A signal to prohibit defrosting operation is sent from the electric box of the outdoor unit that has entered the defrost preparation control operation to the electric box of the outdoor unit for which the defrosting start condition has not been established. The heating operation is forcibly continued until the defrosting operation described below ends. At this time, the air flow rate of the indoor blower during the heating operation is kept at the set air flow rate, and the compressor of the outdoor unit is operated at a variable operating frequency by an inverter, thereby preventing a condensing pressure increase in the heating operation cycle. Next, the outdoor unit during the defrost preparation operation starts the defrost operation after a lapse of a predetermined time. The blower of the outdoor unit that has entered the defrosting operation stops, and the blower of the indoor unit stops or starts the breeze operation depending on the type of the outdoor unit. The defrosting of the frost adhering to the heat exchanger in the outdoor unit is performed by the heat of condensation released from the heat exchanger in the outdoor unit for defrosting. When the defrost ending condition is satisfied by the time condition such as the accumulated time of the defrosting operation and the temperature condition such as the pipe temperature and the outside air temperature, the air volume of the indoor blower and the outdoor blower is returned to the set air volume, and the operation returns to the heating operation.

The outdoor unit that satisfies the defrost start condition based on the time condition and the temperature condition similarly to the previous time enters the defrost preparation control. At that time, it is determined by exchanging information between the unit that performed the previous defrost operation, the unit that performed the heating operation, and the electric box for the outdoor unit, and the unit that performed the previous defrost operation continues the heating operation, The unit that has performed the operation continues the defrost preparation control operation. The defrost operation is started, and when the defrost end condition is satisfied, the operation returns to the heating operation.

By repeatedly performing such control, it becomes possible to alternately perform the defrosting operation and the heating operation until the unit is stopped, and not to enter the defrosting operation at the same time.

[0017]

According to the present invention, after the defrosting operation control is started, it is determined whether the outdoor unit has been subjected to the previous defrosting operation or the outdoor unit which has been subjected to the heating operation. By performing such control, the heating operation can be continued without giving a feeling of cool air to a person or the like in the room.

Further, when one of the outdoor units performs the defrosting operation, the blower in the indoor unit connected to the outdoor unit that continues the heating operation is maintained at the set airflow in the normal operation state. By changing the operating frequency of the compressor, it is possible to prevent an increase in the condensing pressure in the heating operation cycle, to suppress the failure of the compressor, and to ensure the reliability of the cycle.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a connection example of an indoor unit and an outdoor unit according to an embodiment of the present invention.

FIG. 2 is a flowchart of defrost control corresponding to the embodiment of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Indoor unit, 2, 3 ... Indoor heat exchanger, 4, 5 ... Indoor electric box, 6, 7 ... Indoor blower, 8, 9 ... Outdoor unit, 10, 11 ... Outdoor electric box.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Fumio Suzuki 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Air Conditioning Systems Division, Hitachi, Ltd.

Claims (1)

[Claims] In a plurality of independent air conditioners having the same air conditioning target, when one or one of the air conditioners starts a defrosting operation, another air conditioner switches to a defrosting operation. An air conditioner characterized by preventing entry.