US2028783A - Centrifugal pump - Google Patents

Description

' 1935- o. JACOBSEN CENTRIFUGAL PUMP Filed June 5, 1935 2 Sheets-Sheet 2 INVENTOR. CQBO ATTORNEY.

0 rs Tex/v an Patented Jan. 28, 1936 UNITED STATES CENTRIFUGAL PUMP Oystein Jacobsen, Dayton, Ohio, assignor to The Durlron Company, Inc., a corporation of New York Application June 5, 1935, Serial No. 25,101

1 Claim.

The invention relates to centrifugal pumps. It has for its principal object the provision of a construction which will prevent pressure from being built up back of the runner, so that end thrust will be eliminated, and the efliciency of the pump improved. The invention is applicable to both the open and closed type of runner, and briefly stated, involves the-use of a sealing and wear ring at the periphery of. the runner for cutting down leakage from the volute to the rear side of the runner in conjunction with relief ports for permitting a discharge through the runner of any liquid which leaks past the ring. In the open type of runner, the discharge of the leakage to the front side of the runner is promoted by the use of blades or fins on the rear side of the runners which carry the leakage outward to the sealing ring where the discharge ports are located. Certain embodiments of the invention are illustrated in the accompanying drawings, wherein:

Figure 1 is a vertical section through a centrifugal pump of the open runner type embodying the invention. Fig. 2 is a face view of the runner. And Fig. 3 is a section through a modification involving a pump of the closed runner type.

Referring to Figs. 1 and 2 of the drawings which show the invention as applied to the open type of runner, 4 and 5 are parts, of the pump casing which are clamped or bolted together; 6 is the drive shaft provided at one end with an impeller or runner 'l and at the other end having a suitable driving means (not shown), such as a pulley; and 8 is the suction inlet discharging through the eye 9 of the pump.

Extending around the periphery of the casing is the volute I which discharges at I i into the lower end of the outlet passage l2 connected with the usual discharge pipe.

The runner comprises a body portion in the form of the disc l3 provided on its front side or face with the vanes l4, between which are the curved passages l5 (Fig. 2) leading to the periphery of the disc. Extending around the periphcry of the disc is a sealing or wear ring l6, preferably of rectangular cross section having its rear face in parallel with the rear wall of the pump casing, and in close proximity thereto. Although some leakage can occur from the volute to the space back of the runner disc, the arrangement as just described reduces such leakage to a minimum. In order to relieve any pressure which would otherwise accumulate in the space back of the runner disc, the series of ports [I are provided through the disc just inside the sealing ring. The flow of liquid through the passages l5 at the front of the disc applies a suction effect at the ports, so that any liquid back of the disc immediately discharges through the ports. End thrust is thus avoided, and frictional resistance due to the presence of a body of liquid back of the runner disc is avoided.

In order to still further promote the discharge of any liquid in the space back of the runner disc, the rear face of such disc is provided with the seriesof radial vanes or ribs l8 which cause any liquid back of the disc to flow outward to 10 the discharge ports II. The inner wall of the sealing ring, into which the vanes l8 merge, diverts the liquid forced outward by the vanes through the ports. In addition to its sealing function, the ring reinforces the runner and adds 15 to its strength and rigidity.

Fig. 3 illustrates a construction which differs from that of Figs. 1 and 2 in that the runner I9 is of the closed type and no vanes or ribs are applied to the outer faces of the runner disc. In 20 this construction the passages 20 through the disc are similar in shape to those of the open runner construction, and extend from the inlet opening 2| at the center of the runner to the periphery thereof. As in the open type construction, the 25 periphery of the runner is provided with a sealing and wear ring 22, substantially rectangular in cross section, as shown, and having its side faces in parallel with the side walls of the casing and in close proximity thereto, in order to reduce to any leakage to the spaces 23 and 24 to a minimum as heretofore explained. Sets of ports 25 and 26 are provided through the runner disc which function in the same manner as the ports I1, such ports being preferably located just inward of the sealing ring.

What'I claim is:

In combination in a centrifugal pump, 2, casing having an inlet eye at one side and a volute around its periphery, a runner of the open type 40 comprising a disc having on its side next to the eye a series of outwardly extending curved vanes,

a sealing ring of substantially rectangular cross section around the periphery of the disc projecting to the rear of the body of the disc with its rear face in parallel with the side Wall of the casing and in close proximity thereto, a second series of outwardly extending vanes on the rear side of the disc curved reversely of the vanes on the front side of the disc terminating at said ring and arranged so that the two sets of vanes cross intermediate their ends, and ports through the disc in the angles formed. where the concave sides of the vanes of said second series join the sealing ring.

O. JACOBSEN.

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