JPS63148058A - Air conditioner - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to refrigeration cycle control for air conditioners and the like.

Conventional technology A conventional air conditioner will be explained with reference to FIG.

1 is an indoor unit, which includes a compressor 2, a four-way valve 3, and an indoor heat exchanger 4.
, an expansion valve 5, and an outdoor fan 6 are installed. 7 is an indoor unit, which has an indoor heat exchanger 8 and an indoor blower 9.

A refrigeration cycle is formed by connecting a 2t\-no compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an expansion valve 6, and an indoor heat exchanger 8 in an annular manner.

The expansion valve 6 is fixed at a throttle amount that provides the maximum capacity while the compressor 2 is in operation.

Problems to be Solved by the Invention However, when the throttle amount of the expansion valve 5 is fixed, when the compressor 2 is started after being stopped for a long period of time, the refrigerant is dissolved in the refrigerating machine oil in the stopped compressor 2. Due to the existence of the refrigerant in a uniform two-phase gas-liquid phase within the cycle, the operation tends to be short on refrigerant at the initial stage of startup, and the state of the refrigerant in front of the expansion valve 4 is mostly in the gas phase. As a result, the pressure difference before and after the expansion valve 4 becomes large, and the suction pressure of the compressor 2 becomes low, resulting in the drawback that it takes time to achieve sufficient cooling and heating capacity.

In order to solve these conventional problems, the present invention reduces the resistance of the refrigerant flow path when starting the compressor and speeds up the start-up.

Means for Solving Problems 31, -7 The present invention uses an electric expansion valve in the pressure reducing device, and minimizes the amount of throttling when starting the compressor.

According to the above-mentioned structure, the present invention provides a valve opening degree that maximizes the flow rate of the electric expansion valve after the compressor is started until the refrigerant becomes a liquid in front of the electric expansion valve. As a result, blockage caused by gas refrigerant immediately after startup can be reduced, and the compression function can be built up quickly.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1, and the same components as those of the conventional system are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

1o is an electric expansion valve, a compressor 2, a four-way valve 3, an outdoor heat exchanger; 4. , electric expansion valve 10, indoor heat exchanger 8
are connected in a ring to form a refrigeration cycle. Reference numeral 11 denotes a control device for the electric expansion valve 10, which can arbitrarily adjust the valve opening degree.

When the compressor 2 is activated, the refrigerant begins to circulate within the refrigeration cycle. At this time, the electric expansion valve 10 is fully opened by the control device 11.

At this time, the refrigerant is not sufficiently condensed, and the refrigerant passing through the electric expansion valve 1Q has a high proportion of gas phase, but since the electric expansion valve 10 is fully open, refrigerant can be circulated.

When the condensing pressure and temperature rise and the refrigerant in front of the electric expansion valve 1o becomes supercooled, the control device 11 controls whether the refrigerant flows into the electric expansion valve 10 after a certain period of time after starting the compressor 2 or when the refrigerant flows into the electric expansion valve 10. The valve opening degree of the electric expansion valve 10 is set to a preset optimal throttle amount, and the normal operating state is entered.

In this manner, by preventing the gas refrigerant from clogging the electric expansion valve 10 at the initial stage of starting up the compressor 2, and in particular by preventing a drop in the suction pressure of the compressor 2, a quick start-up operation is possible.

Effects of the Invention As is clear from the above explanation, the air conditioner of the present invention has the following effects:
A refrigeration cycle is constructed by connecting a compressor, a four-way valve, an outdoor heat exchanger, an electric expansion valve, and an outdoor heat exchanger in an annular manner, and the electric expansion valve can arbitrarily change the valve opening degree, and the compression Since the electric expansion valves 51 and -7 are fully opened when the machine is started, it is possible to prevent a large drop in the compressor suction pressure due to gas refrigerant blockage in the expansion valve, which occurs in the early stages of compressor startup, thereby reducing the heating and cooling capacity. It has a quick start-up and has a great effect in terms of comfort.

[Brief explanation of the drawing]

Fig. 1 is a refrigeration cycle diagram of an air conditioner that is an embodiment of the present invention, and Fig. 2 is a control flow diagram of an electric expansion valve at the initial stage of compression start-up in Fig. 1. Fig. 3 is a diagram of a conventional air conditioner. It is a refrigeration cycle diagram. 2... Compressor, 3... Four-way valve, 4...
...Outdoor heat exchanger, 8...Indoor heat exchanger, 1o...Electric expansion valve. Name of agent: Patent attorney Toshio Nakao and 1 other person2-
Compressor 3 --- vrt: 2F valve 4- Outdoor 4m'l portable cup 8- Indoor I regular magazine exchange) Moxibustion cup 10--1 Electric expansion valve Fig. 1 Fig. 2 Fig. 3 L J

Claims (1)

[Claims] In a refrigeration cycle in which a compressor, a four-way valve, an outdoor heat exchanger, an electric expansion valve, and an indoor heat exchanger are connected in a ring, the electric expansion valve can arbitrarily vary the throttle amount, and when the compressor is started, An air conditioner with an electric expansion valve that minimizes the throttle amount and maximizes the flow rate.