Oil return device and oil return method of compressor for dual-temperature air conditioner and air conditioning system

Abstract

The invention discloses an oil return device and oil return method of a compressor for a dual-temperature air conditioner and an air conditioning system. The oil return device comprises a double-suction double-discharge compressor, an oil separator and an oil return assembly, wherein the oil return assembly comprises an oil return control valve and a connecting pipe. The oil return device is characterized in that the oil return control valve comprises a shaft, a valve needle, a valve body and a valve seat, wherein the valve body is sleeved with a sleeve; core irons are arranged on the inner wall of the valve body; the shaft is arranged in the middle of the valve body and positioned between the core irons; the lower end of the shaft is connected with the valve needle; the valve seat is arranged at the lower end of the valve body; the valve needle is matched with an inner cavity of the valve seat; an outlet connecting pipe is arranged at the lower end of the valve seat; and the side wallof the valve body is connected with an inlet connecting pipe. The problems that the double-suction double-discharge compressor directly exhausts oil, oil discharging rate in a compression cylinder ishigh, lubricating oil is difficult to return, oil is returned by controlling an adjusting valve, and control is complex can be solved; and the requirement of step heating or refrigerating of indoor air is met, the abrasion of the compressor is reduced, and the service life is prolonged.

Description

technical field [0001] The invention relates to the technical field of air-conditioning systems, in particular to an oil return device for a compressor used in a dual-temperature air conditioner, an oil return method, and an air-conditioning system. Background technique [0002] Existing air-conditioning systems usually use a single-suction single-row compressor, which forms a refrigeration cycle with indoor and outdoor single-row or multi-row heat exchangers to heat or cool indoor air to meet the comfort requirements of the indoor environment. Since the air conditioning system has only one pair of suction and exhaust ports connected to the indoor and outdoor heat exchangers, only one evaporation temperature and condensation temperature can be realized. In order to realize cascaded heating or cooling of indoor air, the patent application number CN105444453A proposes the use of figure 1 The dual-temperature air-conditioning system with dual-cylinder parallel compressors show...

AI Technical Summary

Problems solved by technology

However, in this oil return control method, different operating conditions need to be considered, and the regulating valve on the bypass regulating branch is adjusted to meet oil return and prevent gas leakage. The control of the regulating valve is relatively complicated and costly

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