US2444615A

US2444615A - Eductor

Info

Publication number: US2444615A
Application number: US711306A
Authority: US
Inventors: Albrecht E Reinhardt
Original assignee: Derbyshire Machine & Tool Comp
Current assignee: Derbyshire Machine & Tool Co; Derbyshire Machine & Tool Comp
Priority date: 1946-11-21
Filing date: 1946-11-21
Publication date: 1948-07-06
Anticipated expiration: 1965-07-06

Description

as the inlet 26. This nozzle member may be made of a special erosion-resisting material such as Bakelite, and may be press-fitted in a groove at the upper end of the inlet member, or as shown may be removably mounted on the inlet member by screw threads 3l. A complementary frusto-conical nozzle member 32 is press-fitted or screwed onv the adjacent end of tube l5, and is of such dimensions as to receive nozzle member 3d and thus provide a narrow jet opening 33 which is of least width adjacent the free end of nozzle member 39. In other Words, the outer Wall of nozzle member 3B converges toward the inner wail of nozzle member 32, as is known in the art of jet pumps. The

periphery nozzle

30, 32 may be replaced by a Succession of four or more individual nozzles (not shown) equally spaced circumferentially. Passageway Siri leads to a cleecting surface 35 formed on the upper end of inlet member 25` and adapted to reverse the how of the water jet frompassageway 34 and project it into the space between the

nozzle members

30, 32.

The illustrative jet pump or eductor is a twostage pump, the first stage being the suction caused by the jet opening 33 and the water under very high pressure issuing therefrom into tube I6. This suction draws water and any of its contents from the flooded compartment through openings 26 and 39a and the bore of the tube. A second stage of greater thrust is provided at the upper end of the tube, where a nozzle member 36 is secured by press-fitting or screw threads, and is surrounded by a nozzle member 31. All the nozzle members are preferably of the same material. A jet opening 38 is provided by the converging wells of

nozzle members

36, 31. The effect of the throttling orifice I9 is to diminish the pressure in the chamber 34. A volume greater than one-half of the total ow through conduit Il passes through the second stage of the pump, so that the impelling effect or lift of the jet at the upper end of tube I6 is greater than the `jet at the lower end of said tube. A collar 4D, which is annular, ts around the outside of nozzle member 3l and is screw-threaded as at 4I for engagement with the Aupper end of body I0, thereby holding nozzle member 31 in position. A sealing ring 42, like sealing ring 28, abuts the end of body l and is compressed by a packing and locking ring 43 screwed on threads 4| of the collar 40, so as to form a seal around the jet nozzle.

Secured by screw threads 44 to the inside of collar 40 and in axial alignment with the tube l-S is a diffuser 45 which is: essentially a conduit whose bore 46 for a portion of its length is of the salme size as the bore of tube I6 but for the remainder of its length uniformly increases, as indicated `at 45e. At its upper end diiuser 45 carries a hose coupling 41 or standard pipe connection (not shown and unnecessary to describe), which permits connecting a hose line or pipe to the pump to conduct away the water and debris. A perforated ear 48 is integral with body I0 and projects radially from the cylindrical wall of the body to provide convenient means by which the eductor may be hooked onto a hoist cable or the like for lowering into a compartment and afterwards for raising it without subjecting thecouplings and connections Ato undue stresses. Actually there are preferably two such ears on diametrically opposite sides of the body l0, both in a plane at right angles to the ear 48 shown in the drawing, but for convenience of illustration only a single ear is shown, and in the wrong position.

The enicient conversion of the kinetic energy of liquid flowing through the throat section (i. e., tube I6) into static pressure requires a properly proportioned diffuser 45. Insofar as the interna] diameter of the discharge conduit or hose (which is coupled to the discharge end of the diffuser) determines the maximum diameter of the diiuser at the vdischarge end, and the length and angle of divergence of part 46a of the diffuser have certain critical values for best efficiency, it is apparent that the diameter of said throat section has a maximum value which is a function of the geometry of the diffuser as well as of the operating conditions. Accordingly the internal diameter of the discharge conduit has a very denite influence on the diameter of said throat section. For optimum performance the area of said throat section should be approximately 0.35 times the area at the discharge end of the diffuser. The jet nozzles should be spaced apart a. distance equal to approximately 4 to 5 times the diameter of said throat section, and the lower nozzle should discharge into the throat as near the plane A-A as possible. The upper nozzle should discharge into the diffuser at a point spaced from the lower end of part 46a a distance about equal to the diameter of the throat section.

In actual usein the field, the described eductor will e'iciently clean out flooded compartments, etc., including any muck and debris therein, without ever clogging anything which enters the inlet end being passed on through. Even coarse or large articles such as overalls will be handled without clogging. The jet nozzles are easily removed when worn by erosion and new parts iare readily substituted.

Obviously the present invention is not limited to the preferred embodiment thereof herein described and shown.

Having described one embodiment of my inveritiony what I claim as new and desire to protect by Letters Patent is:

1. An eductor comprising an elongated hollow body having an inlet at its lower end, a tube coaxialiy held within the body to provide an annular passageway for fluid under pressure, a pair of jet nozzles secured at opposite ends of the annular passageway, said jet nozzles co-operating to lift water and debris entrained therein through said inlet and tube, a conduit secured to said hollow body and extending generally -parallel thereto and havingmeans at its upper end for attachment of a hose or the like, said conduit being bent at its lower end to discharge into the annular passageway in a direction at right angies to the common axis of the body and tube, a guide vane within the bent portion of the conduit and dividing the fluid flowing through the conduit into two streams, and a crowned flow-dividing member secured to the body within said annular passageway in the direct vpath of the fluid discharged from the con-duit and co-operating with the guide vane to divide the uid into two streams moving in opposite directions through said passageway to said jet nozzles.

2. An eductor consisting of an elongated hollow body, a straight tube secured co-axially of and within the body and providing therewith an annular passageway for iiuid under pressure, conduit means secured to the body and discharging into the annular passageway at a point about midway between the ends of the tube, means secured to the body to divide the ow from the discharge end of the conduit means into two rl J parts one of which moves toward the upper end of the annular passageway while the other moves toward the lower end, a jet nozzle at the upper end of the annular passageway and another jet nozzle at the lower end, sets of guide vanes extending between the body and tube in said annular passageway and interposed between the two jet nozzles and the discharge end of said conduit and arranged to insure a uniform peripheral jet from each nozzle, an inlet member secured to the lower end of the body and having a central opening which is aligne-d with the tube, said inlet member also having a rounded surface on its upper end to reverse flow of fluid and direct it into the lower jet nozzle, the outer part of the lower jet nozzle being secured to the lower end of the tube and the inner part of the lower jet nozzle being secured to the upper end of the inlet member and surrounding the central opening therein and being surrounded by said rounded surface.

3. An eductor consisting of a hollow elongated body, a straight hollow tube co-axia1 with the body, means to hold the tube rigidly within the body so as to provide an annular passageway for uid, conduit means connected to the body and discharging into said annular passageway midway of its ends, a guide vane in said conduit means near its discharge end and adapted to divide the fluid into two streams, flow-dividing means within the annular passageway and adapted to turn the two streams discharged by the conduit toward opposite ends of the annular passageway, a throttling orifice provided near the lower end of the annular passageway, means ibelow the throttling orifice to reverse the flow of v fluid, a jet nozzle sc disposed as to receive all the fluid whose flow is thus reversed and discharge it into the lower end of the tube, an inlet member secured to the lower end of the body and having a central opening aligned with the tube opening, said jet nozzle being mounted partly on the inlet member and partly on'the tube, another jet nozzle in the upper part of the body and carried ypartly by the body and partly by the tube, the jet nozzles being at the ends of the annular passageway and together discharging all iiuid flowing through the annular passageway, a diffuser secured to the upper end of the body and receiving the discharge jet of the upper jet nozzle, and guide vanes in the annular passageway and so constructed and arranged as to insure a uniform peripheral jet at each j et nozzle.

ALBRECl-IT E. REINHARDT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 47,174 Turrell Apr. 5, 1865 284,962 Huston Sept. 11, 1883 l302,182 Zotoi July 15, 1884 334,597 Marsh Jan. 19, 1886 2,100,185 Engstrand Nov. 23, 1937 2,396,290 Schwarz Mar, 12, 1946