JPS61213560A - Multi-chamber type 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 [Field of Application of the Invention] The present invention relates to a multi-room air conditioner, and more particularly to solenoid valve switching suitable for preventing the generation of impact noise in an indoor unit due to refrigerant pressure during operation switching.

[Background of the invention]

In conventional multi-room air conditioners, when one unit or a small number of units are operated during heating operation, where the capacity of the indoor unit is smaller than the capacity of the outdoor unit, the discharge pressure of the compressor becomes high. When a stopped indoor unit is operated, high-pressure refrigerant suddenly flows into the indoor unit, causing an impact noise from the indoor heat exchanger.

Incidentally, examples related to this type of multi-room air conditioner capable of cooling and heating include Utility Model Publication No. 58-3015.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a multi-room air conditioner that prevents the generation of impact noise in indoor units when switching from a small number of units operation to a multiple unit operation during heating operation.

[Summary of the invention]

The present invention provides a three-way solenoid valve between a compressor and an indoor unit, a refrigerant pipe between a second opening B of the three-way solenoid valve and a heat exchanger of the indoor unit, and a refrigerant pipe that is parallel to the refrigerant pipe. A capillary tube is disposed between the third opening C of the three-way solenoid valve and the heat exchanger of the indoor unit so that when additional operation of the indoor unit is started during heating operation, 3.
The solenoid valve connects the first opening A and the third opening C to prevent high-pressure refrigerant from rapidly flowing into the indoor unit.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure shows an example of a refrigeration cycle circuit diagram of a multi-room air conditioner capable of heating and cooling to which the present invention is applied.

In FIG. 1, a compressor 1 compresses a refrigerant and discharges it as a high-pressure gas refrigerant. 3 is an outdoor heat exchanger, which functions as a condenser during cooling operation and as a heat absorber during heating operation to maintain the temperature at a low temperature. Reference numeral 2 denotes a circuit switching valve that switches between air conditioning and heating, allowing the refrigerant to flow to the outdoor heat exchanger during cooling, and to flow to the piping 24 side during heating operation. 4 is a check valve that allows refrigerant to flow only in the direction of the arrow; during cooling, the refrigerant passes through this check valve and flows in the direction of the arrow.

Reference numeral 5 denotes a heating capillary tube, which allows the liquid refrigerant that has radiated and condensed heat from the indoor unit to flow under reduced pressure to the outdoor heat exchanger 3 side. Reference numeral 6.7 is a refrigerant branching solenoid valve, which functions as a refrigerant artificial valve during cooling operation, and functions as a refrigerant outlet valve during heating operation to select the refrigerant and flow only the indoor unit side port to which the operation command is issued. 1
0.11 is a check valve that allows refrigerant to flow only in the direction of the arrow. Therefore, no refrigerant is allowed to flow during heating operation. 8.9 is a capillary tube for cooling, which reduces the pressure of the refrigerant flowing into the indoor heat exchangers 12 and 13 during cooling. 20, 21, and 22 are pipes that are at low pressure during cooling and high pressure during heating, and 23 are pipes that are always at low pressure. 14.15 is a 3-way solenoid valve,
The first opening A communicates with the four-way valve, the second opening B communicates with the indoor heat exchanger, and the third opening C communicates with the indoor heat exchanger via capillary tubes 16 and 17. ing.

The three-way solenoid valve always opens between the second opening B and the first opening A and closes between the third opening C and the first opening A during cooling.

Moreover, at the time of starting heating operation, the circuit between the third opening C and the first opening A is opened, and the circuit between the second opening B and the first opening A is closed.

Then, the heating operation starts, and after a few seconds have passed, the third opening C-first
The opening A is closed, and the second opening B and the first opening A are opened.

22 is a pipe that has low pressure during cooling and high pressure during heating. 23 is a suction pipe. In such a refrigeration cycle, well-known cooling and heating operations are performed.

FIG. 2 shows the relationship between the discharge pressure and the change in outside air temperature depending on the number of indoor units in operation during heating operation. As is clear from FIG. 2, when one unit is in operation, the refrigerant discharge pressure from the compressor is high. When the second room is operated in such a state, this high-pressure refrigerant rapidly tries to flow into the indoor unit heat exchanger that has started operating. However, for a few seconds at the start of heating operation, the three-way solenoid valves 14 and 15 operate from the first opening A to the third opening C.
In order to open the circuit, the high pressure refrigerant is decompressed in the capillary tubes 16 and 17. Therefore, high-pressure refrigerant does not suddenly flow into the indoor unit.

On the other hand, in cooling operation, the cooling capillary tube 8
．． The refrigerant reduced in pressure at step 9 flows to the indoor heat exchanger 12,13.

As described above, at the start of the heating operation, the high-pressure refrigerant is depressurized by the capillary tube 16 or 17 and flows into the indoor heat exchanger 12 or 13, so that the impact is reduced and the generation of hammering noise can be prevented. FIG. 3 is a flowchart showing the operation. During cooling operation, the circuit is opened from the second opening valve B to the first opening valve A. During heating operation, when an operation command signal is received, the solenoid valve 14.15 is opened for 3 seconds. Open the circuit between open rotor A and third open rotor C. After 3 seconds have elapsed, the circuit between A and C is closed, and the circuit between A and 8 is opened, and normal heating operation begins. Said first opening rotor A → second opening rotor C
Since it takes only a few seconds to open a circuit between the two and allow the refrigerant, which has been depressurized in the capillary tube, to flow into the indoor unit, there is virtually no occurrence of cold air blowing into the room to be heated.

Furthermore, at the start of heating operation in this embodiment, even if only one indoor unit is in operation, it is operated for several seconds through the capillary tube, but after the compressor is started, the refrigerant discharge pressure does not rise suddenly. There is no overload operation, and on the contrary, it has the effect of making control easier.

〔Effect of the invention〕

According to the present invention, when the number of operating indoor units is increased during heating operation, it is possible to prevent the generation of tapping noise due to sudden behavior of refrigerant in the heat exchanger of the indoor unit.

[Brief explanation of the drawing]

FIG. 1 is a refrigeration cycle circuit diagram showing an embodiment of the present invention.
FIG. 2 is a diagram showing discharge gas pressure in one room operation and two room operation in heating operation, and FIG. 3 is an operation flowchart showing one embodiment of the present invention. 1...Compressor, 2...Circuit switching valve, 3...Outdoor heat exchanger, 12.13...Indoor heat exchanger, 14.1
5... Solenoid valve, 16.17... Capillary tube for pressure reduction. Agent: Patent attorney Masao Ogawa V: 1 Not shown, 21.1 Associate (Ton)

Claims (1)

[Claims] 1. In a multi-room air conditioner in which a plurality of indoor units are connected to one outdoor unit, a three-way solenoid valve is provided between the compressor of the outdoor unit and the plurality of indoor units; The solenoid valve has a first opening, a second opening, and a third opening, the first opening is connected to a pipe communicating with the compressor, the second opening is connected to a pipe communicating with the indoor unit, and the third opening is connected to a pipe communicating with the indoor unit.
A multi-room air conditioner characterized in that the opening is connected to a pipe having a capillary tube in parallel to the second opening, and the first opening and the third opening are opened for several seconds at the start of heating operation.