JPS6015849B2 - air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric circuit for an air conditioner in which two indoor units are connected in parallel to one outdoor unit, and the indoor units are operated for cooling simultaneously or by switching.

When a conventional air conditioner is shown in Figure 1, 1 is a compressor, 2 is a
is a condenser, 3 is a first pressure reducer, 4 is a second pressure reducer, 5 is a first evaporator, 6 is a second evaporator, 7 is a first valve, 8 is a second valve, 9, 10, 11, 12 are connecting pipes, 13, 14
, 15 is a blower, 16 is an outdoor unit, and 17 and 18 are indoor units.

The soot discharged by the compressor 1 is liquefied in the condenser 2 and evaporated in the evaporators 5 and 6 for cooling. By opening and closing the valves 7 and 8, the refrigerant can flow to the indoor unit 17 and the indoor unit 18 simultaneously or selectively, and the two rooms can be cooled simultaneously or selectively. The electric circuit of the refrigeration cycle as described above is shown in Figure 2. 19 is the power supply, 20, 21
is the main switch, 22 and 23 are the blower switches, 24,
25 is a cooling switch, 26 and 27 are thermostats,
Reference numerals 28 and 29 indicate power relays that operate the compressor 1 and blower 13, and A, B, C, D, and E indicate contacts that connect the outdoor unit 16 and the indoor units 17 and 18. In such an air conditioner, indoor units 17 and 18
When the valve stops, the first valve 7 and the second valve 8 close,
Refrigerant 0 is divided into the high pressure side of the condenser 2 and the low pressure side of the evaporators 5 and 6, and even after a long period of time, the pressures on the high pressure side and low pressure side are not balanced, so when restarting the compressor 1. The problem was that the load was large and it would not start. Therefore, conventionally, a special compressor 1 with a large starting torque has been used so that it can be started even if there is a pressure difference between the discharge side and the suction side of the compressor 1. However, operating the compressor 1 with a heavy load from the beginning poses problems such as increased wear because the lubricating oil is not sufficiently circulated. 0 In order to eliminate the above-mentioned defects, the present invention makes sure that when the indoor blowers 14 and 15 are rotating and the compressor 1 is stopped, the first valve 7 and the second valve
When the valve 8 of the indoor unit opens, the cooling operation of one indoor unit stops, and then the cooling operation of the other indoor unit starts.
The first valve 7 and the second valve 8 are kept open and the startup of the compressor 1 is delayed, and even if the main switch is turned off, the first valve 7 and the second valve 8 are kept open until the pressure on the discharge side and the suction side are balanced. This relates to an electric circuit that opens the first valve 7 and the second valve 8 so that the pressure is always balanced.

When the electric circuit of the present invention is shown in FIG. 3, 29 and 30 are la
, lc contacts, 31 are la, la', lb
A power relay having contacts, 32 a delay relay having LB contacts, and 33 a delay relay having LA contacts.

In the delay relay 32, the contact lb is closed before energization, and when energized, the contact lb is opened by the heater 34, and remains open for several minutes even after the energization stops. The delay relay 33 has a contact la open before energization, and when energized, the contact la is closed by the heater 35, and remains closed for several minutes even after energization stops. The actual operating state of this device will be explained with reference to FIG. 4. When the main switches 20 and 21 and the blower switches 22 and 23 are turned on, the valves 7 and 8 are energized and opened. The contact la of the relay 29 that the thermostat 24 enters is closed, and the power relay 31 is activated by the electricity that passes through the delay relay 32, and the compressor 1 and the blower 13 are started, the valve 7 is opened, and the first valve 8 is closed. Then, the indoor unit 17 enters cooling operation.
When the thermostat 26 is turned off, the compressor 1 and the blower 13 are stopped, and the first valve 7 and the second valve 8 are opened to balance the pressures. When thermostat 27 turns on, relay 30 goes on.
Contact la is closed, and the indoor unit 18 enters cooling operation. Even if the thermostat 26 of the indoor unit 17 is turned on within the time E (approximately 0 to 3 minutes) when the thermostat 27 is turned off and the compressor 1 and blower 13 are stopped and the pressures are not balanced, the delay relay 32 works to close contact lb. is open for several minutes until the pressure is balanced, so the power relay 31 will not operate and the compressor 1 and blower 13 will not start. After a time F (approximately 3 minutes) during which the pressures are balanced, the contact lb of the delay relay 32 is turned on and the compressor 1 is started. Even if the main switches 20 and 21 of the indoor units 17 and 18 are turned off, the delay relay 33 remains in operation for a period of time G (approximately 3 minutes).
Since the contact lb is closed, the first valve 7 and the second valve 8 are energized and the opening pressures are balanced. As described above, the present invention connects two indoor units to one outdoor unit in parallel, opens and closes the flow of cold soot using the first valve 7 and the second valve 8, and cools the indoor units simultaneously or selectively. In an air conditioner, when the contacts of the thermostats 24 and 25 close, the contacts la of the relays 29 and 30 are closed. Along with starting 1,
Both ends of contact 1a' of power relay 31 are connected to delay relay 32.
A delay relay 33 is connected to both sides of the contact lb of the main switch 20, 21, and has a contact la that remains open for several minutes even after the power is turned off. The first valve 7 and the second valve 8 are opened to balance the pressure, and an electric circuit is provided in which the pressure is always balanced during startup.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional refrigeration cycle, FIG. 2 is an explanatory diagram of a conventional electric circuit, FIG. 3 is an explanatory diagram of the electric circuit of the present invention, and FIG. 4 is an explanatory diagram of the operation of the present invention. 1... Compressor, 2... Condenser, 3...
...First pressure reducer, 4...Second pressure reducer, 5.
...First evaporator, 6... Second evaporator, 7... First valve, 8... Second valve,
13, 14, 15...Blower, 20, 21, 22, 23
, 24, 25... Switch, 26... First thermostat, 27... Second thermostat, 28, 29, 3
0, 31...Relay, 32...Delay relay for starting, 33...Delay relay for stopping, l
a, 1, lb...contact, 35...heater. 1 diagram, 2 diagrams, 4 diagrams

Claims (1)

[Claims] 1 In an air conditioner in which one outdoor unit and multiple indoor units are connected in parallel through valves that open and close the flow of refrigerant, a restart delay is implemented to prevent the compressor from restarting immediately after it has stopped operating. An air conditioner characterized by comprising a control circuit and a pressure balance control circuit that opens the valve for a certain period of time when the pressure on the discharge side and suction side of the compressor is balanced to some extent when the main switch of the indoor unit is open. .