US3093085A

US3093085A - Self-priming pump

Info

Publication number: US3093085A
Application number: US46006A
Authority: US
Inventors: Henry M Pollak
Original assignee: Ingersoll Rand Co
Current assignee: Ingersoll Rand Co
Priority date: 1960-07-28
Filing date: 1960-07-28
Publication date: 1963-06-11
Anticipated expiration: 1980-06-11

Description

June 11, 1963 H. M. POLLAK SELF-PRIMING PUMP Filed July 28, 1960 INVENTOR HEN/P) M. P0 LAK 3,093,085 SELF-PRIMHNG PUMP Henry M. Pollalt, Easton, Pa., assignor to Ingersoll-Rand Company, New York, N.Y., a corporation of New Jerse y Filed July 28, 1960, Ser. No. 46,606

6 Claims. (Cl. 103--113) This invention relates to self-priming centrifugal pumps.

The invention is an improvement and modification of a pump of the type described in co-pending application, Serial No. 31,378, filed May 24, 1960, by Alexander Brkich and assigned to the same assignee as the present application, now U.S. Patent No. 3,082,694, dated March 26, 1963, and differs therefrom in at least one respect in that the discharge of the priming pump does not pass into the discharge line of the main pumping element. In accordance with this invention, gas is evacuated from a liquid head to a centrifugal pump and discharged to atmosphere by a priming pump to completely discharge such air from a system, whereupon the priming element substantially ceases to provide an output.

It is accordingly an object of this invention to provide such an arrangement having means to effectively evacuate the liquid head to a main pump of accumulated air to permit effective pumping of liquid by the main pump.

Another object of this invention is to provide the aforementioned arrangement wherein part of the main pump discharge is transmitted through the priming element to the main pump inlet in a direction opposite to normal flow, when the priming element is pumping, to provide along such flow path a cooling and regenerative flow.

This invention contemplates a self-priming pump comprising a centrifugal rotor disposed in a housing having a rotor inlet and discharge. A priming pump is disposed in the housing and has an inlet connected to the rotor in- 'let, and a discharge normally communicating with atmosphere through a valve. The valve is connected to the rotor discharge and is responsive to pressure thereat for closing such communication to atmosphere and for connecting the two discharges for effecting reverse flow through the priming pump to the rotor inlet.

The invention will be more completely understood, as will other objects and the advantages of the invention, by reference to the following description of a preferred embodiment shown in the drawing, in which the single FIG- URE shows in longitudinal section parts of a centrifugal pump and its priming element and the valve by which the evacuated air is discharged to atmosphere.

Referring to the drawing, it will be noted that the centrifugal pump and priming elements thereof are substantially identical with those of the above mentioned copending application wherein a centrifugal main pump rotor 12 is disposed in a casing or housing having a rotor inlet portion or nozzle 14 leading to the eye of rotor 12 and a rotor discharge passage 16. Housing 10 has a hollow cylindrical extension 18 disposed longitudinally therefrom to house a water ring type pump having a casing 26 and rotor 22 for priming the main pump rotor. For priming the system, air is evacuated from an inlet passage 24 within inlet nozzle 14 by a suitable inlet passage 26, diagrammatically indicated, connected to an inlet cavity 28 within extension 18 of casing 10. Rotation of the priming pump 22 causes discharge of air into a discharge passage 30 having a discharge pipe 32 leading to a valve 34.

As has been said above, the pump, as regards centrifugal and priming parts, is identical with those parts as shown and described in the aforementioned co-pending patent application, and for convenience the foregoing is abridged.

Patented June 11, 1963 Valve 34 consists of a hollow tubular body portion 36, very similar to a pipe T fitting. Two ends of body 36 are fitted with

plugs

38 and 40, while a side aperture 42 and pipe 32 are threadedly connected. Plug 38 has a threaded aperture 44 to receive a suitable lead-off pipe 46. The inner end of aperture 44 forms a port seat 48 adapted to 'be closed by the end of a reciprocal element 50 which may be cylindrical, as shown. Element 50 is also adapted to cooperate with another seat port 52 in plug 40 at the inner end of an aperture 54 threaded to receive a pipe 56 leading to discharge passage 16. Reciprocal element 50 is guided within a sleeve 58 which fits element 50 very loosely. Normally element 50 is held on its seat 52 by a spring 6!) fitting about a reduced end portion 62 of element 5t).

Discharge passage or nozzle 16 is connected to a discharge line 64, and nozzle 16 is preferably provided with a check valve 66 of any suitable and well known construction for sealing the discharge system of the unit so a vacuum is created in the system during the priming cycle to prime the centrifugal impeller 12.

In operation, starting the apparatus by rotation of rotor 12 and the priming pump rotor 22 starts evacuation of air from inlet passage 24, via conduit 26 and discharge passage 32, into the interior of valve body 34, and thence out through pipe 46 to atmosphere or to any convenient place of disposal. Pump rotor 12 is very ineffective at pumping gaseous fluid or air and, therefore, until substantially all the air is evacuated from the system or until at least enough air to submerge rotor 12 has been removed, a vacuum of appreciable value will exist in discharge 16 and in pipe 56. However, as soon as rotor 12 begins to operate on liquid instead of air, pressure will develop in discharge passage 16 and pipe 56' and exerts a pressure against pressure face 68 on the end of element 5t} and in opposition to the force of spring 60 to urge element 50 to close seat port 48. This closure concludes the priming or effective pumping action of the Water ring pump, as rotor 22 is not adapted to develop pressures of any considerable range.

However, rotor 22 will normally continue to churn liquid. Without circulation of liquid the rotor would become heated and consequently troublesome. This heating is prevented by the introduction of liquid in a reverse direction through discharge pipe 32 by Way of the passage afforded between element 50 and sleeve 58. Such liquid can find its way through the priming pump past and in opposition to the rotor 22, and by way of passage 26 to the inlet passage 24.

It will be understood that the elements,

rotors

12 and 22, may be driven by an suitable means, in this instance, a motor 70 suitably supported on casing 10 by a frame 72.

Thus, by the above construction are accomplished, among others, the objects hereinbefore referred to.

I claim:

1. A self-priming centrifugal pump comprising a housing for a rotor and a priming ump and having rotor inlet and discharge passages, a centrifugal rotor disposed in said housing, a priming pump disposed in said housing having an inlet connected to the rotor inlet and a discharge passage, and a valve connected to the priming pump discharge passage normally open to pass fluid from the priming pump to atmosphere, said valve having a pressure face connected to the rotor discharge passage to effect closing of said valve to atmosphere upon development of pressure in the rotor discharge passage and to connect the rotor discharge passage to the priming pump discharge passage.

2. A self-priming centrifugal pump comprising a housing for a rotor and a priming pump and having rotor inlet and discharge passages, a centrifugal rotor disposed in said housing, a priming pump disposed in said housing having an inlet connected to the rotor inlet and a discharge passage, and a valve connected to the priming pump discharge passage normally open to pass fluid from the priming pump to atmosphere, said valve having a pressure face connected to the rotor discharge passage to effect closing of said valve to atmosphere upon development of pressure in said rotor discharge passage, said valve providing a passage connecting the rotor and priming pump discharge passages to each other when said valve is closed to atmosphere and being controlled by said pressure face.

3. A self-priming centrifugal pump comprising a housing for a rotor and a priming pump and having rotor inlet and discharge passages, a centrifugal rotor disposed in said housing, a priming pump disposed in said housing having an inlet connected to the rotor inlet and a discharge passage, a valve having a hollow body portion connected to the rotor discharge passage by a seat port and having another seat port communicating with atmosphere, said valve being connected to the priming pump discharge passage, and a reciprocating element in said valve cooperating with said seat ports to connect said priming pump discharge passage alternatively to said ports.

4. A self-priming centrifugal pump comprising a housin g for a rotor and a priming pump and having rotor inlet and discharge passages, a centrifugal rotor disposed in said housing, a priming pump disposed in said housing having an inlet connected to the rotor inlet and a discharge passage, a valve having a hollow body portion connected to the rotor discharge passage by a seat port and having a second seat port communicating with atmosphere, said valve being connected to the priming pump discharge passage, and a reciprocating element in said valve cooperating with said seat ports to connect said priming pump discharge passage alternatively to said ports, said element having a pressure face associated with said rotor discharge passage closing the first seat port during priming and being responsive to the rotor output to eifect such reciprocations.

5. A self-priming centrifugal pump comprising a housing for a rotor and a priming pump and having rotor inlet and discharge passages, a centrifugal rotor disposed in said housing, a priming pump disposed in said housing having an inlet connected to the rotor inlet and a discharge passage, a valve having a hollow body portion connected to the priming pump discharge passage, said valve having a seat port connected to the rotor discharge passage and another seat port communicating with atmosphere, a reciprocating element in said valve cooperating with said seat ponts to connect said priming pump discharge passage alternatively to said seat ports, and a sleeve fixed in said valve and disposed about said reciprocating element to form a restricted passage from said rotor discharge passage seat port to the interior of said hollow valve body portion.

6. A self-priming centrifugal pump comprising a housing for a priming pump and a pump rotor and having rotor inlet and discharge passages, a rotor disposed in said housing, a priming pump disposed in said housing having an inlet connected to the rotor inlet and a discharge passage, I8, valve having a hollow body portion connected to the priming pump discharge passage and having a pair of seat ports one being connected to the rotor discharge and the other communicating with atmosphere, a reciprocating element in said hollow body portion cooperating with said seat ports to connect said priming pump discharge passage alternatively to atmosphere and the rotor discharge passage, a sleeve fixed in said valve and disposed about said reciprocating element to form 'a restricted passage from said rotor discharge passage seat port to the interior of said hollow body portion, and a spring normally holding said reciprocating element on said rotor discharge passage seat port.

References Cited in the file of this patent UNITED STATES PATENTS 2,149,454 McBath Mar. 7, 1939 FOREIGN PATENTS 304,905 Great Britain Jan. 31, 1929 319,176 Germany Mar. 1, 1920 361,480 Germany Oct. 14, 1922 430,421 Italy Feb. 13, 1948 462,232 Germany July 6, 1928 462,233 Germany July 6, 1928

Claims

1. A SELF-PRIMING CENTRIFUGAL PUMP COMPRISING A HOUSING FOR A ROTOR AND A PRIMING PUMP AND HAVING ROTOR INLET AND DISCHARGE PASSAGES, A CENTRIFUGAL ROTOR DISPOSED IN SAID HOUSING, A PRIMING PUMP DISPOSED IN SAID HOUSING HAVING AN INLET CONNECTED TO THE ROTOR INLET AND A DISCHARGE PASSAGE, AND A VALVE CONNECTED TO THE PRIMING PUMP DISCHARGE PASSAGE NORMALLY OPEN TO PASS FLUID FROM THE PRIMING PUMP TO ATMOSPHERE, SAID VALVE HAVING A PRESSURE FACE CONNECTED TO THE ROTOR DISCHARGE PASSAGE TO EFFECT CLOSING OF SAID VALVE TO ATMOSPHERE UPON DEVELOPMENT OF PRESSURE IN TEH ROTOR DISCHARGE PASSAGE AND TO CONNECT THE ROTOR DISCHARGE PASSAGE TO THE PRIMING PUMP DISCHARGE PASSAGE.