US3250069A - Fluid take-off from turbine pump for cooling systems - Google Patents

Description

R. A. RHODA 3,250,069

FLUID TAKE-OFF FROM TURBINE PUMP FOR COOLING SYSTEMS May 10, 1966 Filed Nov. 4, 1965 q-L-V INVENTOR. RALPH A. RHODA FIG. .1.

ATTORNEYS United States Patent 3,250,069 FLUID TAKE-OFF FROM TURBINE PUMP F0 COOLING SYSTEMS I Ralph A. Rhoda, Berkeley, Calif., assignor to Berkeley Pump Company, Berkeley, Calif., a corporation of California Filed Nov. 4, 1963, Ser. No. 321,035 4 Claims. (Cl. 60-355) This invention relates to cooling systems for engines supplied with water from the discharge end of a hydropump. The invention more particularly involves the location and construction of a fluid take-off from hydropumps through which large quantities of foreign material may passduring normal usage.

Many conventional drive system for watercraft com-, prise a water-cooled engine that drives a turbine-type hydropump. The main discharge from the pump is used for propelling the watercraft, but a fluid take-oil. from the pumps discharge is commonly used for supplying water to acoolant manifold of the engine. Because of the great quantity of foreign material which may pass through the pump, it is necessary to separate out such material before piping the pumps discharge into the coolant manifold. For this purpose, settling chambers and/ or filters are normally used to'separate grit and other particles that might tend to clog the cooling system. While filtering arrangements of various kinds have been used with different success, each suffers from the common disadvantage that frequent periodic cleaning is required.

vanes, and radially inward relative to the trailing edges of the impeller vanes on the downstream side ,of the impeller. Thus, any fluid (and foreign material) which reaches the take-off opening must first pass forward and radially inward. Because of the greater momentum of foreign material compared with the water, very little grit or sand finds its way into the neighboring region of the opening; and since the take-off opening is located radially inward relative to outermost inner surface of the bowl, any material approaching the opening must have been carried against the centrifugal force which normally holds the material against the inside of the impeller bowl, which stream joins the main discharge flow from the pump.

Various objects of this invention will become, apparent in view of the following description and the accompanying drawings.

In the drawings forming a part of this application and in which like parts are designated by like reference numerals throughout the same.

FIG. 1 is a side elevation of a power drive system including a turbine pump for propelling watercraft;

FIG. 2 is an enlarge section and detail taken on lines 22 of FIG. 1' and showing the location and preferred construction of the fluid take-off; and

FIG. 3 is a section and detail taken on lines 3--3 of FIG. 2.

Referring to FIG. 1, there is illustrated a typical pumping system for propelling a watercraft. (not shown). This system essentially comprises a water-cooled engine 10 that drives a turbine pump 11 from which water is conducted through a conduit 12 to the coolant manifold 13 of the engine. In the normal manner of operation, water 3,250,069 Patented 'May 1 0, 1966 from beneath the watercraft is taken into the pump through a bottom inlet 14. The water is then pressurized by the pump and discharged from the end of an impeller bowl 15. A small portion of the pumped and pressurized fluid is also discharged into conduit 12 for cooling engine 10.

This invention is more particularly directed to the location of the point from which water is taken out of pump 11. .The importance of its location is that water fed through conduit 12 will contain very little grit or foreign material, although the main stream of the pump may, in fact, contain a greatdeal. It is-to be recognized that the point of water take-off is of particular importance to a pumping system for propelling watercraft because of the vast amounts of foreign material that are normally taken in and expelled during operation. With standard take-offs, it is essential to employ sometype of filter, and these filters must be cleaned with great frequency and regularity.

Referring to FIG. 2, impeller bowl 15 comprises a twopart assembly of a seal housing 16 having a seal ring 17 and a main bowl housing 18. The general arrangement of this assembly, including the mounting of an impeller 19, is known, but the location of the take-01f passageway 20 is believed to be novel. More particularly, passageway 20 is formed circumferentially of seal ring 17 in housing 16, and terminates with an inner inlet opening 21 located peripherally of and intermediate the travelled paths of the leading edges 22 and trailing edges 23 of impeller vanes 24. Opening 21 is more particularly oriented so that the passageway 20 is exposed radially and atva point radially inward of impeller vane edges 23.

It has been found that the greater density and momentum of foreign material (compared with water) tends to keep it in the main flow stream, while only the water will travel forward relative to the trailing edge 23 of vanes 24. In some instances, some small grains of sand may move to a position circumferentially of vanes 24, but the rotation of impeller 19 will normally keep these grains in movement while centrifugal forces hold the grains against the inner surface of the impeller housing until they are returned to the main discharge stream. Further, since the take-off opening 21 is only radially exposed to the interior of the housing, and at a point radially inward relative to edges 23, any material which passes in front of the opening must be carried against the centrifugal forces acting thereon. This fact alone insures that very little sand can reach opening 21.

FIG. 3 illustrates the preferred shape and location of opening 21 relative to vanes 24. It will be seen that the mouth of opening 21 includes a radial lead 21a that extends radially away from the inner surface of housing 16 but also in the direction opposite to impeller rotation, said lead terminating at an inner circular port 21b, the entry to passageway 20. Lead 21a is thus defined by a projection 25, which extends radially inwardly as well as circumferentially relative to bowl 15 and a relieved surface 26. The function of projection 25 is to shield port 21b from any grains of sand as they are swirled about the inner surface and to force them radially away from said port. While some grains of sand or foreign material may pass across and in front of opening 21, the greater momentum of the grains will cause such material to be bounced across from the surface of projection 25 to the surface 26. At this point the grains will be carried back into the bowl.

It is to be understood that although a preferred embodiment of this invention has been shown and described, various changes may be made without departing from the spirit of the invention or the scope of the attached claims, and each of such changes is contemplated.

What I claim and desire to secure by Letters Patent is:

1. A water craftand propulsion unit comprising:

(a) a water-cooled engine mounted to said craft;

(b) a turbine pump mounted to said craft, said turbine pump comprising: i

(1) an impeller bowl having an inner circular seal located at the intake end thereof;

(2) an impeller disposed within said bowl, said impeller having radial vanes extending into proximate relation to said inner seal and a shroud on the outer radial ends of said vanes, said shroud being supported for rotation by said inner seal and flaring radially outwardly from the leading edge of said vanes in proximate relation to said inner seal, to the trailing edge of said vanes;

(3) said impeller bowl defining a fluid passageway extending radially outward and circumferentially in a direction opposite to impeller rotation from the inner surface of said impeller bowl.

3. A water takeoff as set forth in claim 1 wherein the 5 opening of said passageway is radially shielded by a projection on the leading side thereof relative to impeller rotation and is exposed radially and circumferentially on the trailing side thereof by a relieved surface.

4. A water take-off as set forth in claim 1 wherein the opening of said passageway is located radially inward relative to the trailing edges of said vanes.

References Cited by the Examiner UNITED STATES PATENTS 1,257,793 2/1918 Bodinson 103-102. 1,500,607 7/1924 Conant l03l02 3,030,909 4/1962 Barnes et al. 103-88 FOREIGN PATENTS 188,547 11/ 1922 Great Britain.

SAMUEL LEVINE, Primary Examiner.

HENRY F. RADUA ZO, Examiner.

Claims (1)

1. A WATER CRAFT AND PROPULSION UNIT COMPRISING: (A) A WATER-COOLED ENGINE MOUNTED TO SAID CRAFT; (B) A TURBINE PUMP MOUNTED TO SAID CRAFT, SAID TURBINE PUMP COMPRISING: (1) AN IMPELLER BOWL HAVING AN INNER CIRCULAR SEAL LOCATED AT THE INTAKE END THEREOF; (2) AN IMPELLER DISPOSED WITHIN SAID BOWL, SAID IMPELLER HAVING RADIAL VANES EXTENDING INTO PROXIMATE RELATION TO SAID INNER SEAL AND A SHROUD ON THE OUTER RADIAL ENS OF SAID VANES, SAID SHROUD BEING SUPPORTED FOR ROTATION BY SAID INNER SEAL AND FLARING RADIALLY OUTWARDLY FROM THE LEADING EDGE OF SAID VANES IN PROXIMATE RELATION TO SAID INNER SEAL, TO THE TRAILING EDGE OF SAID VANES; (3) SAID IMPELLER BOWL DEFINING A FLUID PASSAGEWAY EXTENDING THERETHROUGH, SAID PASSAGEWAY OPENING INTO SAID BOWL AT A POINT ON THE DOWNSTREAM SIDE OF SAID INNER SEAL IN PROXIMATE RELATION TO SAID INNER SEAL AND SAID SHROUD, RADIALLY INWARDLY FROM SAID TRAILING EDGES; AND (C) MEANS COMMUNICATION FROM SAID PASSAGEWAY TO SAID WATER-COOLED ENGINE.

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