US1418921A - Rotary pump with ejector - Google Patents

Description

G. HANDLEY.

ROTARY PUMP WITH EJECTOR.

APPLICATaoN man Nov. 23, 1920.

l ,41 8,92 l Patented June 6, 1922.

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GEORGE HANDLEY, OF PALMERS GREEN, ENGLAND, ASSIGNOR 0F ONE-HALF T0 PERCY WILLIAM BULLOCK, 0F LONDON, ENGLAND.

IR'OTAIB'Yv PUMP WITH EJECTOR.

Specification of Letters Patent.

Patented June c, 192e.

Application filed November 23, 1920. Serial No. 426,039.

(GRANTED UNDER THE rRovIsIoNs 0E THE Ac'r 0E Manen 3, 1921, 41 sur. L., 1313.)

To all whom t may concern:

Be it known that I, GEORGE HANoLEY, a subject of the King of Great Britain, residing at Palmers Green, in the county of Middlesex, England, have invented new and useful Improvements Relatin vto Rotary Pumps with Ejectors, (for W ich I have filed application in Great Britain Nov. 13, 1919, Patent No. 159,258), of which the following is a specification.

As is well known, in the operation of a centrifugal pump, the liquid in passing therethrough acquires potential energy which at the outlet from the pump exists largely as pressure. On the other hand, 1n a rotary displacement pump, the energy stored in the liquid at the outlet from the pump is largely kinetic and, consequently, this type of pump has only a lou7 eliiclency when working against low heads. H eretofore it has been proposed to provide an arrangement in which liquid from a vforce pump is delivered through the nozzle o f an injector device whereby additional liquid 1s drawn into the delivery pipe to mingle with that which has passed through the pump. This known arrangement is advantageous in some instances, for example, in pumping from wells or bore holes, by reason of the particular situation from which the liquid is to be raised. The use of an ejector device in combination with a pump of the reciprocatory or oscillating type, does not however suggest that a rotary displacement pump can be made more economical and eicient in operation by providing an ejector device arranged in combination therewith so as to usefully employ the kinetic energy of the liquid issuing from the pump since the potential energy of the issuing liquid in other forms of pump may exist as pressure and therefore may not be so susceptible of being usefully taken out by directing this liquid through the nozzle feed pipe of an ejector.

Now it has been found by experiment that this kinetic energy can be very eliiciently utilized to draw in additional liquid to mingle with the efliuent from the pump by conducting the effluent through an ejector device of the Venturi tube type, and this invention provides a pumping installation wherein a rotary displacement pump has arranged in combination therewith in the delivery pipe-leading from the pump an ejector device of the Venturi tube type operating to draw in additional liquid to mingle with that discharge from the pump chamber. f

In the accompanying drawing which shows how the said invention may be con- Veneniently and advantageously carried into practice:- .f Figure 1 is a vie'w showing a rotary displacement pump having a Venturi tube ejector device arranged in combination therewith in accordance with this invention.

FigureI 2 is a view illustrating a modified arrangement.

As shown in Figure 1, a is a rotary displacementpump having an outlet at `b to which is connected a short length of pipe 'c having a collar d screwed thereon. A gland e is formed between this collar and the pipe 0 in which a cone f is mounted.'

The other end of this cone is scewed in an aperture in the wall of a jet-chamber gand which is made in two parts and a branch.

connection for an auxiliary suction pipe opens at an angle into the lower part of the said chamber.

The upper part of the jet chamber is provided with an outlet lo directly opposite to and in line with the nozzle h. Fitting to this outlet is a pressure cone Z converging in the direction of How of the liquid from the pump, to a narrow throat m of a Venturi tube and from thence increasing in diameter to that of the delivery pipe n to which it i'sjoined.

The operation of these parts is as follows r-Liquid leaving the pump outlet b passes into the cone f which conserves and increases its velocity which becomes a maximum at the mouth of the nozzle h. Crossing the jet chamber g, by virtue of its velocity, the jet of liquid passes into the throat m of the pressure cone Z creating a partial vacuum in the jet chamber. A stream of liquid is therefore drawn into the jet chamber through the suction. pipe j and branch z',

and the combined streams are forced through the throat m into the diverging or expanding part of the cone and into the delivery pipe n.

The liquid drawn in through the suction pipe j may be of a different nature from that issuing from the nozzle h, in any case where it is desired that two different liquids shall' mix whilst being pumped.

In the modified arrangement shown in Figure 2 vihichfshows the invention applied for the purpose of raising water from a well o, a rising main p is provided leading from the lowest level from which water is to be raised and emptying into a tank g placed above theinlet to the pump a. The latter is placed in an inverted position, that is tosa with the inlet above land the discharge be ow, or the pump may be specially constructed for this purpose with the inlet and discharge openings in the required positions. A conduit r is provided for leading a supply of liquid from the tank g to the pump, the surplus liquid accumulating in the tank being led away through an loutflow pipe s.

The pump a imparts energy to a stream of water or other liquid which is forced through a downcast or descendin pipe t running parallel with and beside t e rising main p. The pipes t, p may if desired be arranged one within the other. At its lower end the pipe t terminates in an upwardly directed nozzle u arranged to project a stream of liquid fromthe pipe t at a` high' velocity into the throat v or constricted portion of a Venturi tube w which is formed on the lower end of the rising main p and serves as an ejector device or augmenter. The artial vacuum thereby created raises the llquid surrounding the lower open end of the Venturi tube fw and lifts it into the throat o where it comes into contact-with the stream issuing from the nozzle u and is -carried into the rising main p. This portion of the contrivance is an adaptation of a known device, called a jet pump, by which a certain quantity of liquid can be made to set in motion a much larger quantity by Y reason of its superior pressure head.

It will be seen that therotary pump a does not act directly on the liquid to be raised from the bottom of the well o, but

' operates through the medium of the hquid propelled through the downcast pipe t. The advantage of this arrangement is that the pump can be installed at the surfaceofl the ground, only the downcast pipe augmentor w and rising main p being placed 1n the well. of augmentors can be arranged instages so that the pressurer in the pipes need not eX- ceed that required to lift the liquid from stage to stage.

The advantageof the inverted arrangement of pump is that liquid from the container or tank can flow directly into the inlet, thus enabling the pump to be run at a higher speed than if a suction supply is provided. Also, the pump delivery being beneath, enables the pump to be placed directly over the downcast pipe, thus avoiding loss of velocity by bends in the pipe. This is a special advantage in the case of rotary pumps which impart their rotary or centrifugalvelocity to the water. For pumps of the positive rotary type the supply can be strained off from the main outiow. i Y

The improved arrangements hereinabove described can be applied to raising fluids as well as liquids.

vWhat I claim is A The combination, with a rotary displacement pump, of a Venturi tube ejector, which For excessive depths a number` pump and comprises a jet chamber having a shouldered socket, a nozzle fttin into said shouldered socket in said jet-c amber, a conical tube having its smaller end engaging said shouldered socket in .said jet-chamber, and a` gland connected tothe outlet of said pump and securing the larger end of said conical tube.

Signed at London, England this 10th day of November, 1920. Y

GEORGE HANDLEY.

In the presence of- HERBERT A. BEEs'roN,

E. MURPHY.

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