Back to results
US 2004/0175279 A1Published application
Self priming centrifugal pump
AssigneesRomeo Ramacciotti, Renzo Biondi, Enrico Menegoni
InventorRomeo Ramacciotti
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneesRomeo Ramacciotti, Renzo Biondi, Enrico Menegoni
InventorRomeo Ramacciotti
Estimating the term…
A centrifugal pump comprising a pump body (1) housing an impeller (3) keyed onto a motor shaft (4) and provided with a suction mouth (7) and a discharge mouth (8) capable of being made to communicate with, respectively, a suction pipe (9) and a discharge pipe (10). Between the suction mouth (7) and the suction pipe (9) there is provided a chamber (22) that communicates with a tank (11) situated at a level higher than the level of the pump, said tank being interposed between the discharge mouth (8) and the discharge pipe (10) and in communication with both of them and communicating also with the chamber (22) through a recirculation duct (28) having a section smaller than the section of the suction pipe (9). Between the tank (11) and the chamber (22) there is also provided means (13) for cutting off the flow that are controlled by the pressure existing in the tank to automatically cause the liquid to be recirculated in the tank to automatically cause the liquid to be recirculated through the chamber 822) and into the pump whenever the pressure in the tank drops below a predetermined value.
A centrifugal pump comprising a pump body (1) housing an impeller (3) keyed onto a motor shaft (4) and provided with a suction mouth (7) and a discharge mouth (8) capable of being made to communicate with, respectively, a suction pipe (9) and a discharge pipe (10), characterized in that between said suction mouth and said suction pipe there is provided a chamber (22) that communicates with a tank (11) situated at a higher level than said pump, said tank being interposed between said discharge mouth (8) and said discharge pipe (10) and in communication with both of them and communicating also with said chamber (22) through a recirculation duct (28) having a section smaller than that of the suction pipe (9), between said tank (11) and said chamber (22) there being also provided means (13) for cutting off the flow that are controlled by the pressure existing in said tank and to automatically cause the fluid to be recirculated through said chamber (22) and into the pump whenever the pressure in said tank drops below a predetermined value.
A centrifugal pump in accordance with any one of the preceding claims, wherein said tank (11) comprises an internal wall (12) for dividing it into a first and a second chamber (11a,b) such that the first chamber (11a) communicates with the discharge mouth (8) and the discharge pipe (10) and the second chamber (11b) with the recirculation duct (28), said first and second chamber communicating with each other through an opening (5) formed in said wall (12) where it meets the bottom of the tank, said means (13) for cutting off the flow being interposed between said second chamber (11b) and the recirculation duct (28).
A centrifugal pump in accordance with any one of the preceding claims, wherein the section of said recirculation duct (28) is about half the section of the suction duct (9).
A centrifugal pump in accordance with any one of the preceding claims, wherein the flow section of said annular passage (29) is smaller than the section of said recirculation duct (28).
A centrifugal pump in accordance with any one of the preceding claims, wherein the liquid is discharged into said tank (11) through a nozzle in the form of a right-angle bend (31) that extends from the tank bottom into said first chamber (11a).
A device for rendering a centrifugal pump self-priming, characterized in that it comprises a body (21) capable of being interposed between the suction pipe (9) and the suction mouth (7) of the pump, said body delimiting an internal chamber (22) that can be communicated with the suction pipe by means of a first inlet port (24) and to the suction mouth by means of an outlet port (25) and being further provided with a second inlet port (23) that communicates through a recirculation duct (28) with a tank (11) arranged at a level higher than the level of the pump and communicating with both the discharge mouth (8) of the pump and a discharge pipe (10), said recirculation duct (28) having a section smaller than the section of the suction pipe (9) and comprising means (13) for cutting off the flow that are controlled by the pressure existing in said tank, so that recirculation of the liquid through said chamber (22) and into the pump will be automatically started whenever the pressure in said tank (11) drops below a predetermined value.
Dependencies are inferred from the claim text.