US2057979A

US2057979A - Water wheel bucket

Info

Publication number: US2057979A
Application number: US726699A
Authority: US
Inventors: Joseph J Ring
Original assignee: Allis Chalmers Corp
Current assignee: Allis Chalmers Corp
Priority date: 1934-05-21
Filing date: 1934-05-21
Publication date: 1936-10-20
Anticipated expiration: 1953-10-20

Description

Oct. 20, 1936. J. J. RING WATER WHEEL BUCKET Fi led Mag, 21, 1934 Patented Oct. 20, 1936 PATENT OFFICE WATER WHEEL BUCKET Joseph J. Ring, Wauwatosa, Wis., assignor to Allis-Chalmers Manufacturing Company, Milwaukee, Wis.,,a corporation of Delaware Application May 21, 1934, Serial No. 726,699 4 Claims. (01. 253-114) This invention relates to improvements in the construction of buckets for hydraulic turbinesof the impulse type and more particularly tobuckets which are built up from several elements rather than formed as an integral structure.

Heretofore the buckets of impulse hydraulic turbines were formed as single units by processes such as casting by which the ellipsoids forming the bucket itself and the means for attaching the bucket to the rotor disc were formed at the same time. Such integral construction however required a separate pattern for each type and size of bucket and each bucket had to be separately cast. After casting, the buckets had to 15 be annealed to relieve casting stresses and each bucket then had to be separately finished. Such finishing required that the bucket be balanced and also finished to obtain uniform weight distribution in each bucket to avoid unbalance 20 stresses acting either centrifugally or laterally.

It is readily apparent to even those not skilled in the art, that the above process is uneconomic and must result both in lack of uniformity of the product and in high cost.

25 It is therefore among the objects of the present invention to provide a bucket construction for impulse hydraulic turbines in which the bucket is assembled from a plurality of separably formed elements rather than formed as an in- 30 tegral structure.

Another object of the invention is to provide a bucket construction for impulse hydraulic turbines in which a bucket is built up from a plurality of elements which are each interchange- 35 able with similar elements.

Another object of the invention is to provide a bucket for impulse hydraulic turbines in which the bucket is built up from a plurality of elements which are in substantially finished condition thus 40 avoiding extended finishing operations on the irregular outline structure formed by the bucket.

Another object of the invention isto provide a bucket construction for hydraulic turbines'of the impulse type in which the bucket is built up from a plurality of elements which can be separately replaced to avoid scrapping the entire bucket upon wearing out of one portion thereof.

impulse wheel bucket built up from a pluralityv 55 of separate elements;

. type.

- Fig. '2 is a side elevational view of the structur illustrated in Fig. 1; and

. Fig. 3 is a cross-sectional view taken on the plane III-III of Fig. 2 to illustrate the arrangement of the elements receiving and retaining the 5 ellipsoids forming the jet receiving portion of the bucket and to illustrate the manner in which the receiving and retaining portions are interconnected.

Referringmore particularly to the drawing by characters of reference, the reference numerals 5 and 6 designate adjacent ellipsoids which are preferably forged or stamped from a single piece of sheet material such as boiler plate and which form the jet receiving portion of a bucket construction for a hydraulic turbine of the impulse Due to the construction of the ellipsoids from sheet material, it may be diificult to secure a properly shaped jet divider or splitter at the intersection of the surfaces of the ellipsoids. If a sharpened and extended splitter-is required, a separate knife shaped member I is suitably segurec; in the ellipsoids as shown in section in The ellipsoids are set into and retained within a retaining structure or holder which may be termed a reinforcement, preferably formed from separate elements. The major elements of the holder are

plates

8 and 9 which are cut out to receive the ellipsoids. The

plates

8 and 9 extend about the ellipsoids in a direction substantially parallel with the greater axis thereof and extend rearwardly from the ellipsoids to provide means for engaging the rotor disc (not shown) to which the plates are to be secured by suitable means employing the apertures formed therein. The

plates

8, 9 are spaced by a bracing member ll extending from the outer convex surface of the ellipsoids, at approximately the midpoint thereof, downwardly and rearwardly between and in contact with the plates. The

plates

8, 9 and the brace II are joined by suitable means such as welding, bolting or riveting. The forward edge of the plates and the portions thereof adjacent the rear portion of the ellipsoids are joined by substantially semi-circular straps l2 and 13 to which the ellipsoids are attached by suitable means. The upper edge portions of the ellipsoids between the

plates

8, 9 are secured to a plate M which is suitably attached to the 7

plates

8, 9 and extends therebetween. The semicircular straps I2, l3 are further stiffened by arc shaped straps I6 and I! which extend from approximately the center section of the straps I2, [3 about the ellipsoids and extend into contact with the

plates

8, 9 to which they are attached. The several elements of the holder are thus formed and joined in such manner as to form a basket-like structure into which the ellipsoids are set and in which such ellipsoids are retained.

From the above it will be apparent that the several elements of the bucket are separately formed from plates or sheet material which is commercially manufactured to close limits and in highly finished form. The probabilities of deviation of weight in any number of the several elements are accordingly very slight thus eliminating the necessity for finishing of the completed structure to remain within predetermined weight limits. The several portions are produced in quantities by machine and are already in highly finished condition and require only such finishing asmay be desired from the view point of appearance. Any one of the portions may be removed from a completed structure and be replaced without damage to'the other portions thereof thus greatly reducing maintenance cost. The ellipsoids are firmly retained in the holder which is stayed and braced by the reinforcement, in every direction in which forces act thereon. The ellipsoids themselves therefore need be made only heavy enough to withstand corrosion and erosion because the forces tending to deform them are taken up by the various elements of the holder. Such elements are sufficiently uniform in shape to render calculation of the strength thereof relatively simple.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

portion thereof.

It is claimed and desired to secure by Letters Patent:

1. A built up bucket for hydraulic turbines of the impulse type comprising jet receiving ellipsoids, and a reinforcement, for said ellipsoids, and comprising members respectively engaging a substantial portion of the edges of said ellipsoids, and extending transversely of and engaging the bottoms of said ellipsoids.

2. A built up bucket for hydraulic turbines of the impulse type comprising a plurality of joined jet receiving bowls of substantially ellipsoidal form, and a holder for said bowls forming a reinforcement comprising members extending around the periphery of said bowls from one end of the jet entering portion thereof to the other end of the jet entering portion thereof and members respectively extending along the convex surface and longitudinally of said bowls from the jet entering edge of the bucket to and beyond the opposite edge thereof to serve as lugs for attaching the buckets.

- 3. A built up bucket for hydraulic turbines of the impulse type comprising a plurality of joined jet receiving bowls of substantially ellipsoidal form, and a reinforcementcomprising a member extending around the periphery of said bowls from one end of the jet entering portion thereof to the other end of the jet entering portion thereof.

4. A built up bucket for hydraulic turbines of the impulse type comprising a plurality of joined jet receiving bowls of substantially ellipsoidal form, and a reinforcement comprising members respectively ext-ending along the convex surface and longitudinally of said bowls, transversely of said bowls, and around the periphery of each of said bowls from one end of the jet entering portion thereof to the opposite end of the'jet entering JOSEPH J. RING.