Ejector

Patent metadata

Field	Value
Publication number	US-11549522-B2
Application number	US-201916452758-A
Country	US
Kind code	B2
Filing date	Jun 26, 2019
Priority date	Jan 26, 2017
Publication date	Jan 10, 2023
Grant date	Jan 10, 2023

Abstract

An ejector includes a nozzle, a needle and a body. The nozzle reduces a pressure of a fluid and discharges the fluid as an injected fluid from a fluid injection port. The body includes a fluid suction port and a pressure increasing portion. The fluid suction port draws, as a suction fluid, a fluid from an outside of the body by using a suction force generated by the injected fluid. The pressure increasing portion increases a pressure of a mixture of the injected fluid and the suction fluid. The nozzle includes a throat portion and a nozzle-side tapered portion. The throat portion reduces a passage cross-sectional area of the fluid passage to be smallest in the fluid passage at the throat portion. The nozzle-side tapered portion expands the passage cross-sectional area of the fluid passage toward the downstream side in the flow direction of the fluid. In an axial cross section, an injection-flow spread angle formed on the downstream side in the flow direction of the fluid between a central axis and a tangent line of an injection-flow center line at the fluid injection port is 0° or greater.

First claim

The invention claimed is:

1. An ejector comprising: a nozzle that reduces a pressure of a fluid in a liquid phase or a fluid in a gas-liquid two-phase and discharges, as an injected fluid, the fluid in the liquid phase or the fluid in the gas-liquid two phase at a high speed from a fluid injection port; a needle that is disposed in a fluid passage defined in the nozzle and extends along a central axis of the nozzle; and a body including a fluid suction port that draws, as a suction fluid, a fluid from an outside of the body by using a suction force generated by the injected fluid, and a pressure increasing portion that increases a pressure of a mixture of the injected fluid and the suction fluid, wherein the needle includes a tip portion that protrudes from the fluid injection port toward a downstream side of the fluid injection port along a flow direction of the fluid, the nozzle includes a throat portion that reduces a passage cross-sectional area of the fluid passage to be smallest in the fluid passage at the throat portion, and a nozzle-side tapered portion that extends from the throat portion to the fluid injection port and expands the passage cross-sectional area of the fluid passage toward the downstream side in the flow direction of the fluid, the needle is configured to close the fluid passage, in an axial cross section of the ejector along which the central axis extends, lines perpendicular to the central axis are defined as virtual vertical lines, points at which the virtual vertical lines intersect with an outer surface of the needle are defined as needle-side intersection points, points at which the virtual vertical lines intersect with an inner surface of the nozzle-side tapered portion are defined as nozzle-side intersection points, middle points between the needle-side intersection points and the nozzle-side intersection points on the virtual vertical lines are defined as midpoints, and a line passing through the midpoints is defined as an injection-flow center line, wherein in the axial cross section, an injection-flow spread angle formed on the downstream side in the flow direction of the fluid between the central axis and a tangent line of the injection-flow center line at the fluid injection port is 0 or greater, the needle includes a needle-side p located radially inside the nozzle-side tapered portion, and an outline of the needle-side portion is curved convexly along the flow direction of the fluid maximum outer diameter portion of the needle in the axial cross section.

2. The ejector according to claim 1 , wherein
the fluid passage of the nozzle includes a pre-injection passage that is defined between the outer surface of the needle and the inner surface of the nozzle-side tapered portion, and
the pre-injection passage has a passage cross-sectional area that increases toward the downstream side along the flow direction of the fluid.

3. The ejector according to claim 1 , wherein
the needle-side portion has a cross section that increases toward the downstream side along the flow direction of the fluid.

4. The ejector according to claim 1 , wherein
an outline of the nozzle-side tapered portion linearly extends in the axial cross-section.

Assignees

• Denso Corp

Inventors

• Suzuki Tatsuhiro
• Ogata Gota
• Kawamoto Yoichiro
• Fukushima Ryu

Classifications

• F04F5/04 Primary

  displacing elastic fluids · CPC title

• B60H2001/3298

  Ejector-type refrigerant circuits · CPC title

• F04F5/46

  Arrangements of nozzles · CPC title

• F04F5/461

  Adjustable nozzles · CPC title

• F25B5/04

  arranged in series · CPC title