US2354304A - Turbine runner - Google Patents

Description

July 25, 1944.

O. CELlO TURBINE RUNNER Filed Feb. 22, 1943 lnventor Orlano Celio Patented July 25, 1944 vori-.milo Celio, Soleure, switzerland Application February 22, 1943, Serial No. 476,783

, In Switzerland July 2, 1942 9 claims.

lon'a.- mass production basis Moreover, owing to the precise workmanship required in their construction and the complicated mounting of the blades which must be' assembled in correct spaced relation to each other, such'runners are very expensive.'

-The novel construction of this invention inherently eliminates the aboveand like disadvantages of known arrangements and methods of mounting turbine runners Iby employing a laminated core xed preferably between two coaxial -circular half-sections of the vrunner body and consistingl of a plurality of superposed plates disposed concentrically to the axis of rotation of the runner, said plates being provided with a series of notches around their periphery, the

A,notches of each plate being angularly displaced with respect to the notches of adjacent plates so as to .form in said core stepped grooves con- `forrningvto the cross sectional contour of the blades which are inserted into said grooves and held therein against removal in vboth axial and radial direction by inwardly directed flange portions of the runner body overlapping the inserted ends of said blades. z v

The invention also consists in the further features as. hereinafter described and set forth' in the dependent claims.

In the accompanying .sheetY of explanatory drawing: s

Fig. 1 is a front elevation partially in section of the assembled turbine runner according to the invention; y y f Fig. 2 is a side elevation of said runner looking in vfrom the -left of Fig. 1; 1

Fig. 3 is a detail View showing a singleelement of the blade carrying coreof the runner;

Fig. 4 lis ra detail front elevation and Fig. 5 is a top planv view Vof a single blade, the latter of said gures showing also adjacent portions of the blade carrying core;

Fig. 6 is a detail view showing elements ofthe blade carrying core in displaced relation.

Referring to the drawing, wherein like numerals of reference designate corresponding parts throughout the several views, the improved construction comprises a runner disk formed with two coaxial circular half-sections I and 2 whichV are united at their inner ends, .and 'a laminated core 3 mounted between said half-sections and carrying a series of radial blades 4 equally distributed along the periphery ofltherunner. As shown in Figs. 4 and 5, the blades '4 may be bounded by a' 'convex cylindrical surface on their leading side and by a concave cylindrical surface on their trailing or'reaction side, the elements of these twocylindrical-surfaces being normally parallel and extending from end to end of the blades.

The core V3 is shown composed of a plurality of superposed circular plates 5 disposed perpendicularly and concentrically to the laxis of rotationrof the runner and formedeach with a centrally disposed circular recess 6 anda seriesvof holes 9 alining with corresponding Aholes ID in the two half-sections I and. 2 ofthe runner disk, said holes being adapted to receive rivet pins Il or any suitable equivalent by means of whichsaid plates n mayl be assembled and fixed tothe runner disk.

Moreover, the plates 5 are shown vprovided with a series of milled notches extending between radial teeth l, the notches being preferably of the same size and uniform spacing around the periphery of any one yplate. However, the width of the notches 'on successiveplates may be varied. Further, as clearlyshown in Fig, 6, thenotchesand teeth 'l of each plate are angularly displaced with respect to, the notches and teeth .,'l and l ofadjacentplates so as to form in the c ore 3 stepped grooves 8 the inner and outer edges of which merge into a curved or rounded contour that is adapted to conform to the contour of the blades 4 (Fig. 5). To ensurethe desired angularity ofthe notches of superposed plates, the teeth 'l of each plate are set at a determined distance e from the radius interconnecting the centers of thekrecess 6 and one of the holes 9 (Fig. 3). ,It'will Ibe seen that the distance exon successive plates is a vfunction of the curve of the blade. l Y

, The facing central bosses of the parts I and 2 of the runner diskform an internal hub I2 upon which vmay be seated a centering ring `I3 having an outer diameter equalito the inner diameter of the recess 6 in the'plates 5. vThe said ring may be used to center-the core 3 on the runner disk and also to hold thetwo half-sections of said disk in correct `position with respect to each other.

.. The blades 4 of the runner., which arebest seen in Figs. 4 and 5 of the drawing, may be of any suitable form to which the staggering or angular displacement of the notches in successive plates can always be adapted. It will be seen that the precision of conformity of the grooves 8 formed in the laminated core 3 to the contour of the blades increases with the number of plates used.

The inner ends of the blades 4 are narrowed as at I4 to form a neck wherein are engaged the inwardly directed outer anges I and 2 of parts I and 2 of the runner disk. The sides of the neck I4 being flat, the neck is closely confined between the said anges on the runner disk and, hence, also serves to maintain the desired angularity of the blades.

The assembling of this runner is the following:

The laminated core 3 is built up on' the ring I3, the various notched plates 5 being combined and superposed in a manner to form the stepped grooves 8 conforming to the contour of the blades 4. The precise mutual angular adjustment of successive plates is obtained by keeping their holes 9 in alignment. A blade is` then inserted into each one of said grooves and, nally, the half-sections I and 2 of theA runner Vdisk are placed laterally on the ring I3 thereby overlapping the neck I4 0f the blades at I and 2 which are thus secured in position and retained against removal. The whole of this structure is held together by the rivets II.

The necks I4 are formed to fit closely the flanges I `and 2, and it isA immaterial to the final form of the device whether theblades are indi# vidually machined to form thenecks or are machined as a group to form theY necks while the blades are spaced by the laminated core 3.

It will be seen that the laminated core 3 maintains the circumferential spacing of the blades and assists in maintaining their radial position. Besides, it has also the function of transmitting the force reaction of the blades to the clamping halves of the runner disk. On the other hand, the opposed flanges at the periphery of the disk by which this clamping effect is produced hold;

the blades against motion in the axial as well as in an outward radial direction and, at the same time, maintain their angularity under the action of jets.

From the foregoing, it is believed that the construction and advantages of the present invention may be readily understood by those skilled in the art without further description, it being borne in mind that numerous changes may be made in the details disclosed without departing from the spirit of. the invention as set out in the following claims.

I claim:

l. A turbine runner, in particular for steam and gas turbines, having in combination a runner disk, at least one series of .appropriately contoured blades extending substantially radially from the periphery of said disk, a blade carrying laminated core mounted on said disk and comprising a plurality of superposed plates disposed concentrically to the axis of rotation of the run* ner, said plates being provided witha series of notches around their periphery, the notches of each plate being angularly displaced with respect to the notches of adjacent plates so as to form in said core stepped grooves approximately conforming to the cross sectional contour of the blades which are Y inserted into said grooves, means for centering said core on the runner disk, and means formed on said disk and directly engaging portions of the blades to retain the blades against removal in both axial and radial directions.

2. A turbine runner, in particular for steam and gas turbines, having in combination a runner disk, at least one series of appropriately contoured blades extending substantially radially from the periphery of said disk, a blade carrying laminated core mounted on said disk and comprising a plurality of superposed plates disposed concentrically to the axis of rotation of the runner, said plates being provided with .a series of lnotches around their periphery, the width of the notches on successive plates being varied and the notches of each plate being angularly displaced with respect to the notches of adjacent plates so as to form in said core stepped grooves the inner and outer edges of which merge into a curved contour conforming to the cross sectional contour of the blades which are inserted into said grooves,

means for centering said core on the runner disk, and clamping means on said disk directly engaging portions of the blades Ato fix the radial and axial position of the blades and also their angularity. l

3. A turbine runner, in particular for steam and gas turbines, comprising in combination a runner disk constructed of two coaxial half-sections having each a centrally disposedhub and an inwardlyl directed circular ange portion at the periphery, at least one series of blades extending radially from the periphery of `said disk, said blades being bounded by a convex cylindrical surface on their leading side and by a concave cylindrical surface on their trailing ror re actionl side, a blade carrying laminated core mounted between said half-sections and centered on the hubs thereof, said core consisting of a plurality of superposed circular plates disposed perpendicularly to the axis of rotation of the runner, said plates being provided with a series of notches around their periphery, the width of the notches on successive plates being varied and the notches of each plate being angularly displaced with respect to the notches of adjacent plates so as to form in said corerstepped grooves the inner and outer edges of which merge into a curved contour conforming tothe cross sectional contour of the blades which are inserted with one end into said grooves and held therein against removal in both axial and radial direc tion by the inwardly directed flange portions of the runner disk overlapping the inserted ends of said blades.

4. A turbine runner as claimed in claim 3, the inserted end of the blades being narrowed toform a neck having flat sides adapted to be closely conned between the inwardly directed flange por# tions of the runner disk.

5. A turbine runner as claimed in claim 3, wherein the blade carrying laminated core is centered on the hubs of the half-sections of the runner disk by the intermediary of a centering ring serving, at the same time, to hold said half,- sections in correct position with respect4 to each other, and wherein common means are provided for assembling the plates of the laminated core and fixing the assembled core to both the half-sections of said runner disk.

6. A turbine runner comprising in combination a pair of mating disks having complementary hubforming portions and having on and near the periphery of their proximate faces, annular grooves adapted to receive and confine lugs on turbine blades; a circumferential series of concavo-convex turbine blades mounted around the periphery of said disks and retained between the same, said blades having lugs closely confined in said grooves; a laminated core interposed between said disks and made up of a plurality of plates each plate having a notched periphery, successive blades being received in and confined by successive notches in said laminated core and the plates being angularly offset so that their notches lit the concavo-convex curvature of the blades; and means clamping said disks together upon said core and blades and serving to prevent rotation of said laminated core relatively to said disks.

'7. The combination defined in claim 6 in which the means which connects the disks passes through the core and thus serves as means for preventing relative rotation of the core and the disks.

8. A turbine runner comprising a plurality of radiating blades, each blade being formed with a convex cylindrical leading face and a concave cylindrical reaction face, the edges of said blades being cut away near their inner ends to produce a reduced neck and an adjacent larger head at the inner end of the blades, at least the neck having flat parallel surfaces at a definite angle to the reaction face of the blade; a pair of complemental disks having a peripheral annular rib, the ribs on the two disks being presented toward each other and engaging the necks of the blades, such engagement fixing the angular position of the blades and the heads preventing outward movement of the blades; a laminated core comprising a plurality of circumferentially notched circular plates conned between said disks with successive blades received in successive notches of the plates, the dimension of the notches in each plate and the positions of the plates being so chosen as closely to coniine the portion of the blade with which each plate coacts; and means for locking the disks and plates into a rigid structure whereby the disks confine theblades against radial and angular movement and the plates space the blades and transmit their face reaction to the disks.

9. A turbine runner comprising a pair of mating disks having complementaryr hub forming portions, and having near the periphery of their proximatefaces an' offset forming an annular rib; a ring surrounding and centering the hubforming portions of said disks; a plurality of appropriately contoured turbine blades mounted in a circular series around, and projecting beyond, the periphery of said disks, said blades being arranged approximately radially with respect to the disks and having neck forming grooves which receive and closely iit the ribs on the disks, whereby the disks positively position the blades angularly and against motion in radial directions; a laminated core comprising a plurality of plates interposed between said disks and centered by said ring, each plate having a circumferential series of peripheral notches which closely confine the inner ends of said blades; and means connecting the disks and the laminated core to form a unitary structure in which the laminated core serves to space the blades circumferentially and the disks positively position the blades in all other respects.

ORLANDO CELIO.

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