Ejector-type refrigeration cycle

Patent metadata

Field	Value
Publication number	US-10495350-B2
Application number	US-201515513508-A
Country	US
Kind code	B2
Filing date	Aug 18, 2015
Priority date	Oct 24, 2014
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

An ejector-type refrigeration cycle has a compressor, an ejector module, a discharge capacity control section, and a pressure difference determining section. The ejector module has a body providing a gas-liquid separating space. The pressure difference determining section determines whether a low pressure difference operating condition is met. The low pressure difference operating condition is an operating condition in which a pressure difference obtained by subtracting a low-pressure side refrigerant pressure from a high-pressure side refrigerant pressure a predetermined reference pressure difference or lower. The body is provided with an oil return passage that guides a part of a liquid-phase refrigerant to flow from the gas-liquid separating space to a suction side of the compressor. The discharge capacity control section sets a refrigerant discharge capacity to be a predetermined reference discharge capacity or higher when the low pressure difference operating condition is determined to be met.

First claim

What is claimed is:

1. An ejector-type refrigeration cycle comprising:
a compressor that compresses a refrigerant and discharges the refrigerant, the refrigerant being mixed with a refrigerant oil;
a radiator that causes the refrigerant discharged from the compressor to radiate heat;
an ejector module having a body, the body providing
a nozzle portion that reduces a pressure of the refrigerant flowing out of the radiator,
a refrigerant suction port that draws a refrigerant as a suction refrigerant using a suction action of an injection refrigerant jetting out of the nozzle portion,
a diffuser passage that mixes the injection refrigerant and the suction refrigerant and increases a pressure of the refrigerant, and
a gas-liquid separating space that separates the refrigerant flowing out of the diffuser passage into a gas-phase refrigerant and a liquid-phase refrigerant;

an evaporator that evaporates the liquid-phase refrigerant separated in the gas-liquid separating space; and
a controller programmed to:
control a refrigerant discharge capacity of the compressor; and
determine whether a low pressure difference operating condition is met, the low pressure difference operating condition being defined as an operating condition in which a pressure difference obtained by subtracting a low-pressure side refrigerant pressure in the ejector-type refrigeration cycle from a high-pressure side refrigerant pressure in the ejector-type refrigeration cycle is equal to or lower than a predetermined reference pressure difference, wherein

the body is provided with an oil return passage that guides a part of the liquid-phase refrigerant, which is separated in the gas-liquid separating space, to flow from the gas-liquid separating space to a suction side of the compressor, and
the controller sets the refrigerant discharge capacity of the compressor to be higher than or equal to a predetermined reference discharge capacity when the low pressure difference operating condition is determined to be met,
the predetermined reference pressure difference is a value at which the liquid-phase refrigerant separated in the gas-liquid separating space can be reliably returned to the suction side of the compressor through the oil return passage, and
the predetermined reference discharge capacity is a value at which the liquid-phase refrigerant separated in the gas-liquid separating space can be reliably returned to the suction side of the compressor through the oil return passage.

2. The ejector-type refrigeration cycle according to claim 1 , further comprising
an outside air temperature detector that detects an outside air temperature, wherein
the controller determines that the low pressure difference operating condition is met when a detection value of the outside air temperature detector is equal to or lower than a predetermined reference outside air temperature.

Assignees

• Denso Corp

Inventors

• Kume Makoto
• Yamada Masahiro
• Tashiro Toshiyuki
• Araki Yoshinori
• Nishijima Haruyuki
• Nagano Youhei
• Yokoyama Yoshiyuki

Classifications

• F25B41/00

  Fluid-circulation arrangements · CPC title

• F25B2341/0012

  Ejectors with the cooled primary flow at high pressure · CPC title

• F25B2700/2117

  of an evaporator · CPC title

• F25B49/02

  for compression type machines, plants or systems · CPC title

• F25B2700/1931

  Discharge pressures · CPC title