US1048564A - Elastic-fluid turbine. - Google Patents

Description

J. F. METTEN.

ELASTIC FLUID TURBINE.

APPLICATION FILED NOV. 9, 1911. RENEWED NOV. 9, 1912 W/T/VL'SSES Patented Dec. 31, 1912.

I I I l UNITED STATES PATENT OFFICE.

JOHN F. METTEN, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE WM. CHAMP & SONS SHIP 8:. ENGINE BUILDING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELASTIC-FLUID TURBINE.

vApplication filed November 9, 1911, Serial No. 659,839. Renewed November 9, 1912.

Y '0 all whomit may concern Be it. known that I, JOHN F. ME'rrnN, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Elastic-I luid Turbines, of WlllCh the following is a full, clear, and exact specification.

Thisinvention relatesto elastic fluid turbines and has for its objectan improved mounting for the blades in the revolving or stationary member of a steam or gas turbine, by means of which they are more securely locked against displacement under cent-rifugal thrust and torsional strainsand may be assembled with greater convenience than by the methods commonly employed, and by which a lighter and stronger structure may be secured.

Various methods of securing the blades to the elements of a turbine have been heretofore employed. In one method, grooves are cut in the drums the full width of the blades, which are held in place by soft metal packing pieces spaced between, and calked so as to be swelled into serrations cut into the grooves and the adjacent sides of the blades. This method,-although cheap in construction, is objectionable in that, if any calked section is defective, the blades are liable to strip under the centrifugal strains, which produces disastrous results to the machine. Other methods are to rivet the blade to a strip of metal and bend the latter to fit a groove of the drum; or to provide an undercut groove and mill the roots of the blades of a proper shape to dovetail with the undercut channels' In all of these types a shallow groove is employed so that with Weak or careless calkin'g the blades are liable to work loose and become displaced under the combined effort of rotary and centrifugal strain or the blades; will lack proper lateral rigidity if the lit in the grooves is not perfectly tight. By reason of theirditlicult mechanical structure, some of them are, moreover, open to objection on account of manufacturing expense.

, By my construction I overcome possibility of damage through defective local callging and secure the blades in position by a Specification of Letters Patent.

Patented Dec. 31, 1912.

Serial No. 730,492.

cross section of the support. I secure these" desirable results by making the root of the blade deep relatively to its width and lock the blades to their support by milling hemispherical recesses on opposite sides of the root to receive steel balls by which the blades are firmly locked against relative slip. Wide shoulders are formed near the junction of the root of the bladewhich find a secure abutting surface on the face of the drum or disk, and the blades are assembled with intervening soft metal space blocks and then driven into undercut or serrated channels until the shoulders squarely engage the face of the drum, the space blocks thereby extending into the serrations and in conjunction with the steel balls, anchoring the root in two planes against displacement under centrifugal thrust or circumferential strain or flexure. i 1

My invention, therefore, consists in a turbine blade mounted in a deep and relatively narrow recessed groove in the rotary element and locked in place by unyielding walls at all faces of its root.

I t embodies also various other more specific features, the noveltyofWhich will be hereinafter more fully describedin the speci' fication and definitely indicated in the claims.

in the accompanying drawings which illustrate my invention, Figure 1 is a part sectional view of a blade mounting embody iug my invention; Fig. 2 is a similar View on a plane at right angles to that of Fig. 1; Fig. 3 is a top plan view of Fig. 1; Fig. 4 is a sectional view showin my invention as applied to a disk rotor o a turbine.

Referring now to the drawings in detail, 1 represents the turbine blade, the root of which, 2, is milled off with square shoulders 3 to engage corresponding'wall's on the face of the drum or disk of the rotary element of the turbine. Suitable slots are milled in the face of the .drum or disk in which the ratio of the width to the depth is very much less than in the systems of mounting heretofore in vogue. or serrated as indicatedat t, to it .int.e

being; died with a smell hemispherical recess :2 adopted to form a seat for a rein-tirely hard ball, such as steel, or other si' itable key toloclt the blades and the filling meets in position;

Between each pair er blades is placed a filling block t of metal, the lateral faces of which are recessed to form. nseat for the balls. A group of the blades are assembled in the slot side by, side with the intcrveiling packing blocks, steel bells fitting: snugly between the corresponding cavities block and. root of the blade, and the blocks are subjected to pressure by milking the exposed ends so as to cause the soft metal to expand into the serrations or groo es in the walls of the drum. The bells thus form a rigid connection between the block 6 and the root. of the blude,'encl if any peeking block should. not be czi-lked hard enough to thoroughly iillthe'serrations in th groove, the balls will form an interlock between it and the adjacent'blades, which will preventthecentrifugal force due to the revolution of the cylinder or disk carrying the blades from pulling out the blade without also drawing out the packing block. An important. advantage of: this form of construction is the great. rigidity due to the milled shoulders 2, 3 and the depth of the slot; moreover, as the s.ots are cut in raised shoulders on the surface oi the drum, as indicatcd in Fig. l, the thickness of metallic Wall between these shoulders can be less than the thickness required. if the slots were the full width of" the blade, which means-a vli ghtcr form tion, the space he dcrs being adapted for the shrouding on nudes, scly to ether, to fill the groove, and the exposed ends of the blocks culkcd so as to expand into the serrations in side of groove. It ll be evident that, by reason of the =tiun oi the milking material into the Tutituis of the grooves and by reason of completely embeddiu the interlocking the blades are rigidly supported centrifugal thrust on all sides of the root. Elorerrser, by reason of the depth of the root, a nnich more stable construction is provided against circumferential thrust asihe distance is greater between the tor on the shoulder-*5 2, 3, and the If the blades are lines show the section of metal required in revolving disks with undercut slots to receive the blade, and the full lines show the section of metal required for the type of binding herein described, It will be noted that tlupart represented the reference characters 6, 7, 8, 9 replaces the packing sections or dislzn'ico pieces between the blades of this type of turbine and that this is not addiiionel weight, might at first appear.

Higving thus described my invention, I ileclai'e that what I claim as new and desire to secure by Letters Patent, is:

1. In a turbine, the combination of a blade having a root embedded in serrated groove in a, supporting member, hard metal keys interlocl-zing with sockets in the root, and soft metal packing filling the groove and embedding the keys and serrations.

2. In a turbine, the combination or a se ries of blades having roots embedded in a serrated groove in a supporting member, a series of steel balls seated in cavities in the roots, and soft-metal compressible pecking separating the roots of the hind In a turbine, the cornhi blade having a root deep cliiti width with wide bearing shcmldcrs to engage the periphery of the support, and. rigid k ys. iniei'lnclt ug on all sides with the root 7. 2 wells to prevent displaceci' centrifugal or rotary thrust. -l. ln a turbine, the combiimtion of a series of blades with intervening soft metal dercut groove in one of the elements, space blocks of soft metalcompressed in serrations of the grooves, and a of steel halls interlocking with recessed surfaces of the roots of the blades and with the compressed'spaee blocks.

6. In a till-blue, the combination of a series of grooved blades having'deep roots with hearing shoulders engaging the face of the rotary -element, an undercut g'oove in the rotary element, a series of steel balls interlockingwith the side walls of thejroots, and soft metal space blocks partly surrounding each ball and the undercut groove and compacted into tight engagement therewith.

7. 1m a turbine, thecombination of a series of 'groove-d blades having roots .relatively deep to their thlckness'and right on gled bearing shoulders engaging the face of the rotary element, an undercut groove in the face of the rotary element, a sericsof steel-balls engaging hemispherical steel neccsses in the side walls of the roots, and soft motel space blocks with corrcsgwnding hemispherical recesses, the space blocks being compacted into the grooves to, .mnbed the 1 In testimonv whereof I afiix my signature, roots and undercut grooves. 111 Drogonmr of two witncssis.

S. In :1 turbine. the combination of :1 W V. v

' JOHN P. MIJL'ILA.

groovad support, :1 plurality of blades spare 5 blocks and interlocking balls botweon the \\'irm;-s es:

blades, whereby the blades are locked in lsur Ax-nxovr, position. Cum. \V \VILLIAM.

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