JPH04208366A - air conditioner - Google Patents

Abstract

PURPOSE:To prevent heating, deforming of a scroll blade of a compressor at the time of recovering refrigerant by controlling to close a first two-way valve at the time of recovering the refrigerant, controlling to open a second two-way valve, and, recovering the refrigerant stored at an outdoor side heat exchanger side to a scroll compressor side through a bypass tube and the second valve by the suction pressure of the scroll compressor. CONSTITUTION:When a room heating is started, a scroll compressor 1 is operated, a four-way valve 2 is switched, a two-way valve 8 is closed and a two-way valve 14 is opened for a predetermined time. Thus, refrigerant stored at an outdoor side heat exchanger side is recovered to the compressor 1 side through a bypass tube B, the valve 14 and a capillary tube 15 by the suction pressure of the compressor 1. In this case, a scroll blade is cooled by cooled liquid refrigerant recovered to the compressor 1. As a result overheating, deforming of the blade can be prevented.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to an air conditioner equipped with a refrigerant heater.

(Prior art) Some air conditioners are equipped with a heat pump refrigeration cycle and a refrigerant heater, and perform indoor heating by combining the heat pumping action of the heat pump refrigeration cycle and the refrigerant heating action of the refrigerant heater. be. - An example is shown in FIG.

Variable capacity compressor 1, four-way valve 2, outdoor heat exchanger 3, check valve 4 (forward), pressure reducer such as electric expansion valve 5, indoor heat exchanger 6, four-way valve 2, and check valve 7 (in the forward direction) to form a heat pump refrigeration cycle.

A two-way valve 8 and a refrigerant heater 9 are successively communicated from the communication portion between the check valve 4 and the expansion valve 5 to the suction port of the compressor 1.

The refrigerant heater 9 is additionally equipped with a gas burner 10, which is connected via a proportional valve 11 to a fuel supply source (not shown).

Note that an outdoor fan 12 is provided near the outdoor heat exchanger 3,
An indoor fan 13 is provided near the indoor heat exchanger 6.

Explain the action.

When cooling a room, the compressor 1 is started with the two-way valve 8 closed, and the refrigerant is flowed in the direction of the solid arrow shown in the figure, so that the outdoor heat exchanger 3 becomes a condenser and the indoor heat exchanger 6 becomes an evaporator. and perform cooling operation.

When heating a room, the compressor 1 is started with the two-way valve 8 open, the four-way valve 2 is switched, and the refrigerant heater 9 is operated (the gas burner 10 is combusted). The indoor heat exchanger 6 works as a condenser and the refrigerant heater 9 works as an evaporator by flowing the refrigerant in the direction of the heating operation.

At the start of this heating operation, the two-way valve 8 is kept open and the refrigerant heater 9 is kept off for a predetermined period of time, and the refrigerant (including the lubricating oil of the compressor 1) accumulated in the outdoor heat exchanger 3 is compressed. The air is recovered to the compressor 1 side by the suction pressure of the compressor 1. This prevents the amount of refrigerant circulating during the refrigeration cycle from becoming insufficient.

(Problem to be solved by the invention) However, in an air conditioner using a scroll compressor as the compressor 1, when refrigerant recovery as described above is performed, negative pressure occurs in the case of the scroll compressor, and the scroll blades There is a problem that cooling is insufficient. Therefore, there is a problem in that the scroll blades become overheated and deformed.

The present invention has been made in view of the above points, and its purpose is to provide an air conditioner using a scroll compressor that can prevent overheating and deformation of the scroll blades of the compressor that occurs during refrigerant recovery. The aim is to provide the opportunity.

[Structure of the invention] (Means for solving the three problems) The subject of the present invention is a scroll compressor and a four-way valve.

Outdoor heat exchanger 1 communicates with a heat pump type refrigeration cycle formed by communicating an electric expansion valve and an indoor heat exchanger from a communication part between the outdoor heat exchanger and the electric expansion valve to the suction port of the scroll compressor. a refrigerant heater provided at the refrigerant heater, an i-th two-way valve provided at the inlet of the refrigerant heater, and a bypass pipe that bypasses the refrigerant heater and the first two-way valve;
A second two-way valve disposed in the bypass pipe and the first two-way valve are controlled to close, and the second two-way valve is controlled to open to remove the refrigerant accumulated on the outdoor heat exchanger side. means for recovering refrigerant to the scroll compressor side via the bypass pipe and the second two-way valve; a four-way valve, an indoor heat exchanger, an electric expansion valve, a first The present invention is solved by an air conditioner characterized in that it is equipped with a two-way valve, a means for flowing a refrigerant through a refrigerant heater, and a means for operating the refrigerant heater to perform heating operation.

(Function) At the time of refrigerant recovery, the first two-way valve is closed and the second two-way valve is closed.
The two-way valve is controlled to open and the refrigerant accumulated on the outdoor heat exchanger side is transferred to the bypass pipe and the second
is recovered to the scroll compressor side via the two-way valve.

Thereafter, the first two-way valve is controlled to open, and the second two-way valve is controlled to close, so that the refrigerant discharged from the scroll compressor is transferred to the four-way valve, the indoor heat exchanger, the electric expansion valve, and the first two-way valve. Flow through the two-way valve, refrigerant heater, and operate the refrigerant heater to perform heating operation.

(Example) An example of the present invention will be described below with reference to the drawings. In Fig. 1, the same parts as in Fig. 4 are given the same numbers; however, 1 is a variable capacity scroll compressor),
The explanation thereof will be omitted.

In FIG. 1, a bypass pipe B is provided to bypass the refrigerant heater 9 and the two-way valve (first two-way valve) 8. A two-way valve (second two-way valve) 14. A cabling tube 15 is provided.

In addition, the variable capacity scroll compressor 1, four-way valve 2, outdoor heat exchanger 3, check valve 4, electric expansion valve 5, check valve 7, two-way valve 8.14, refrigerant heater 9 (burner 10 and Proportional valve 1
1), an outdoor fan 12, and the like constitute an outdoor unit.

Moreover, at least the indoor heat exchanger 6 and the indoor fan 13
This constitutes an indoor unit.

The control circuit is shown in FIG.

Connect the power terminal of the indoor control unit 40 to the commercial AC power supply 30, and connect the power line 31 to the power terminal of the indoor control unit 40.
The outdoor control section 50 is connected via the.

An indoor temperature sensor 41, a light receiving circuit 42, and a fan motor 13M of the indoor fan 13 are connected to the indoor control section 40. The light receiving circuit 42 includes a remote control operation unit (
It receives infrared light transmitted from a remote controller (hereinafter abbreviated as remote controller) 43.

The four-way valve 2, the electric expansion valve 5, the two-way valves 8 and 14, the proportional valve 11, the fan motor 12M of the outdoor fan 12, and the inverter circuit 51 are connected to the outdoor control section 50.

The inverter circuit 51 rectifies the alternating voltage of the power supply line 31, converts it into an alternating voltage of a frequency corresponding to a command from the outdoor control section 50, and outputs the alternating voltage. A compressor motor IM of the variable capacity scroll compressor 1 is connected to the output end of the inverter circuit 51.

The indoor control section 40 and the outdoor control section 50 are connected to each other by a serial signal line 32 synchronized with the power supply voltage, thereby enabling data transfer between the two.

The indoor control section 40 and the outdoor control section 50 each include a microcomputer and its peripheral circuits, and perform overall control of the air conditioner. That is, in the indoor control section 40 and the outdoor control section 50,
It is equipped with the following Keyaki Noh means.

(2) The operation of the scroll compressor 1, the non-switching of the four-way valve 2, the closing of the two-way valves 8 and 14, and the operation off of the refrigerant heater 9 are set, and the refrigerant discharged from the compressor 1 is switched to the four-way valve 2. The refrigerant flows into the indoor heat exchanger 6 through the outdoor heat exchanger 3, the check valve 4, and the electric expansion valve 5, and the refrigerant that has passed through the indoor heat exchanger 6 is returned to the scroll compressor 1 through the four-way valve 2 and the check valve 7. , a means of performing cooling operation.

■Means for determining the difference between the temperature detected by the indoor temperature sensor 41 and the set temperature of the remote controller 43 during cooling operation, and controlling the operating frequency of the scroll compressor 1 (output frequency of the inverter circuit 51) according to the determined difference. .

■ Set the operation of the scroll compressor 1, switching of the four-way valve 2, closing of the two-way valve 8, and opening of the two-way valve 14, and transfer the refrigerant accumulated on the outdoor heat exchanger side to the bypass pipe B and the two-way valve. 14 to the scroll compressor 1 side.

■ Set the operation of the scroll compressor 1, switching of the four-way valve 2, opening of the two-way valve 8, closing of the two-way valve 14, and operation of the refrigerant heater 9 (combustion of the gas burner 10), The discharged refrigerant flows 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 to the refrigerant heater 9. A means for returning the refrigerant that has passed through the four-way valve 2 to the scroll compressor 1 to perform heating operation.

■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 determined as the heating load, and the operating frequency of the scroll compressor 1 (output frequency of the inverter circuit 51) is controlled according to the heating load. means to do.

Next, the operation will be explained.

When the desired room temperature is set using the remote controller 43 and the heating operation is started, the scroll compressor 1 is operated and the four-way valve 2 is switched over as shown in FIG. is closed, and the two-way valve 14 is opened.

As a result, the refrigerant accumulated on the outdoor heat exchanger side is transferred to the bypass pipe B by the suction pressure of the scroll compressor 1 to the bypass pipe 1.
4. Recover to the scroll compressor 1 side via the cabling tube 15.

At this time, the scroll blades are cooled by the cooled liquid refrigerant collected in the scroll compressor 1. As a result, overheating and deformation of the scroll blades are prevented.

When the refrigerant recovery for the predetermined period of time is completed, first, the temperature detected by the indoor temperature sensor 41 and the set indoor temperature are compared.

If the temperature detected by the indoor temperature sensor 41 is lower than the set indoor temperature, the two-way valve 8 is opened as shown in FIG. The direction valve 14 is closed, and the refrigerant heater 9 is operated (
combust the gas burner 10).

Then, the refrigerant flows in the direction of the broken line arrow of the first cause, forming a heating cycle, the indoor heat exchanger 6 acts as a condenser, the refrigerant heater 9 acts as an evaporator, and warm air is blown into the room. .

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

C Effects of the Invention As detailed above, according to the present invention, an air conditioner employing a scroll compressor is capable of preventing heating and deformation of the scroll blades of the compressor during refrigerant recovery. can be provided.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a refrigeration cycle according to an embodiment of the present invention, FIG. 2 is a diagram showing the configuration of a control circuit of the same embodiment, FIG. 3 is a timing diagram for explaining the operation, and FIG. The figure is a diagram showing the configuration of a refrigeration cycle of a conventional air conditioner. 1... variable capacity scroll compressor, 2... four-way valve,
3... Outdoor heat exchanger, 5... Electric expansion valve, 6...
, indoor heat exchanger, 8, 14... three-way valve, 15...
Calibration tube, 9... Refrigerant heater, 10...
Gas burner 40...indoor control section, 50...outdoor control section, B...bypass pipe. Applicant's agent Patent attorney Takehiko Suzue No. 1 [! ff 2nd rM

Claims (1)

[Claims] A heat pump type refrigeration cycle consisting of a scroll compressor, a four-way valve, an outdoor heat exchanger, an electric expansion valve, and an indoor heat exchanger are connected to each other, and the scroll compressor is connected to a communication section between the outdoor heat exchanger and the electric expansion valve. A refrigerant heater provided in communication with the suction port of the machine, a first two-way valve provided at the inlet of the refrigerant heater, and a bypass pipe that bypasses the refrigerant heater and the first two-way valve. , a second two-way valve disposed in the bypass pipe, and controlling the first two-way valve to close and controlling the second two-way valve to open the refrigerant accumulated on the outdoor heat exchanger side. means for recovering the refrigerant to the scroll compressor side via the bypass pipe and the second two-way valve; 1. An air conditioner comprising: a two-way valve; a means for causing a refrigerant to flow through a refrigerant heater and operating the refrigerant heater to perform a heating operation.