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Any of various types of jet pumps used to withdraw fluid materials from a space. Also known as eductor.
A device that ejects the finished casting from a mold.
A device in the breech mechanism of a gun, rifle, or other firearm which automatically throws out an empty cartridge case, or unfired cartridge, from the breech or receiver.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a device in which kinetic energy is transferred from a medium that is moving at high velocity to another medium. The energy is transferred as the media are mixed (seeJET APPARATUS). Ejectors are used in jet and vacuum pumps. They are widely used as mixers in the chemical and petroleum-refining industries.


Sokolov, E. Ia., and N. M. Zinger. Struinye apparaty, 2nd ed. Moscow, 1970.
Gubin, M. F., Iu. N. Gornostaev, and K. A. Liubitskii. Primenenie ezhektorov na gidroelektrostantsiiakh. Moscow, 1971.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

ejector, ejector pump

1.A type of pump for ejecting liquid, as from a sump; induces fluid flow by entraining the liquid in the flow of a stream of air, steam, or water.
2. A cleanout, 1.

sump pump, ejector

sump pump
A pump used to remove the accumulated waste in a sump.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.


i. A form of jet pump used to transfer fluids from one location to another. Ejectors are normally used in the feeder or the main tank, in which the booster pump is installed to ensure that this tank is never empty. The ejectors suck in fuel from the other tanks.
ii. Any device to eject something (e.g., links of gun ammunition in a belt are ejected from the gun into the aircraft fuselage or the atmosphere by an ejector).
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved
References in periodicals archive ?
The small spring is quite powerful, requiring eight to nine pounds of pressure to push the ejector pin flush with the bolt face surface.
Few modeling works are available on Coanda-effect ejectors, which gives rise to improving some existing devices.
Ejector cooling cycles using low-pressure refrigerants, such as R134a or R1234yf, can also have noticeable performance improvements.
In 1915 the Triple-Lock was removed from production to be replaced by the 2nd Model Hand Ejector without the third lock and without the enclosed ejector rod.
The key to these opportunities is in finding a suitable high-pressure fluid capable of driving (motivating) the ejector. In many cases the motive fluid used is energy normally wasted, thereby making the ejectors free to operate.
Products in the piCompact10 range are smaller and lighter than conventional ejectors, reducing the total weight of vacuum handling systems, which also allows vacuum systems to move more quickly to increase production capacity.
It is also insurance against a prolonged outage, as most large ejectors are custom-designed and delivery of parts, even on a rush basis, will take at least a few weeks.
Ejector vacuum systems, for example, have been common in the chemical industry for nearly a hundred years.
[ClickPress, Wed Aug 21 2019] Jet ejectors are the simplest devices among compressors and vacuum pumps.
Expansion work recovery devices such as ejectors which recover the kinetic energy released during the expansion instead of dissipating it in a throttling process are known to be beneficial to cycle performance.