US974160A

US974160A - Turbine-bucket.

Info

Publication number: US974160A
Application number: US38863907A
Authority: US
Inventors: Alfred H Kudlich
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1907-08-15
Filing date: 1907-08-15
Publication date: 1910-11-01
Anticipated expiration: 1927-11-01

Description

TURBINE BUCKET.

APPLIOATION FILED AUG..15. 1907. 974.160. Patented Nov. 1, 1910.

IrwVenbor-g oql'Fr-'ed H. udiich,

narrow mouth of the vundercutgroove in UNITED STATES PArENr oEEIoE.

l. ALIg'RED H. KUDLICH, 0F LYNN, MASSACHUSETTS, .ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION F NEW YORK.

TURBINE-BUCKET.

Specification of Letters Patent.

' Application ined August-15, 1907. serial No. 588,639.

Patented Nuv.1,'191o.

To all whom tt may concern.' f I Be it known that I, ALFRED H. KUDLIGH,

a citizen of the United States, residing at bin'es, in whichftherotating element is provided with a' plurality of 'curved blades upon which the steam lmpinges; It is customary, in large units, to make the blades separate and secure them in rows upon the periphery of the bucket wheel. A common Inode of fastening the bucket is to cut away one end of it to frm a dovetailed tenon which is inserted' insan undercut groove in the edge of thebucket wheel, or in a segment which. is afterwardattached to the wheel. The cutting of the tenon wastes a rconsiderable quantity-of the metal, and one of theobjectsof my invention is to prevent this waste. Furthermore, owingfto the thinning ,of the bucket toward its edges, the tips of the `\do'vetailed ten`onare its narrowest and weakes portions, whereas the parts which 'engage .the lowest part of the side walls of the undercutg'roove should be the strongest, because at Athat point there is a greater thickness of metal in the wheel to resist centrifugal force.` Then vit is reme`m-v bered that a bucket weighing one pound mounted on the vperiphery of a. twelve foot wheel making 600 revolutions per minute exerts a centrifugal force of 736 pounds, the necessity for a strong and unyielding fastenina becomes apparent. A further object, therefore, of my invention, is to strengthen the parts which retain the bucket in the groove.

I accomplish the results aimed at by slotting the sides of the bucket in toward the middle thereof, leaving sufficient metal between the inner ends ofthe slots to fill the the bucket-wheel or segment. The horns .produced these slots arethen-,bent in a forward and backward direction; beyond the plane of'lthe bucket, and preferably toward th concave side of the bucket so that their outer'ed'ges'are parallel and stand just far' enough apart to t against the side walls of the undercut portion of the groove. The

customary spacing blocks are interposed between the bases ofthe adjacent buckets.

In the aceomp'an'yin" drawings, Figure 1 is a side elevation, art y in section, of a portion of a bucket vv eel and a ewrbucltets se cured thereto after the manner of my invention; Fig. 2 is a. longitudinal crossf'section thereof, on' the line 2 2, Fig. ltFig. is a radial cross-section on the' line B-3, Fig, 2; and Fig. 4 is a perspective view er eue of the buckets y The wheel 1 has an undercut groove in its periphery. At some convenient point the side of the wheel is cut away to foi-in a lat eral inlet to said groove. "Ths inletis closed by a block 2, conforming to theshape of the groove and secured by a transverse .rivet 3.

The bucket thas two eppostely located slots a 5 extending into its 'sides parallel with and near its bottom. The portion of the neck or shank 6 of the bucket petween the inner 'ends of said slots is just wide enough tol fit snugly in the narrow mouth of the underout groove in the wheel. The horns 7 formed on the flower end of the, neck or shank by cutting these slots are then bent beyond the plane of the bucket and preferably both toward the concave side of the bucket until their Youter sides stand parallel with each other; that is, transverse to a line joining the outer edges of the bucket.r The outer walls of the groove are ofa the roper height to recevetbese horns, so that tile-y lie snugly between the bottom of the roove and the overhanging metal above. he upper edges of the horns aiforda long bearing' surface to resist the radial strain on lthe bucket dueto centrifugal force. p y g The buckets are assembled in ithegroojve b y removin the block '2 and slipping the buckets in tterally through the inlet and then sliding them along the groove. Space ing or filling blocks 8 are interposed between adjacent buckets, fitting(- also between the horns 7. If desired, the pitch maybe regulated by machining oit the tips of the horns so that the length of the horns is the same on all the buckets. 4The tips of the horns on one vbucket are then abutted against the convex back of the next bucket, thus spacing all the buckets at e ual distances. The lilling between the bucrets may then be effected by lpouring in melted tvpe-metal or thellike, instead of using solid blocks slipped in alternately with the buckets.

It will be seen that the above-described construction cuts down stresses in the blade or bucket to something like and affords greater utilization of stock by increase of holding surface thereby affording a much stronger fastening for the buckets.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my device together with the apparatus which I now consider to represent the best embodiment thereof; but I desireto have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means.

NVhat I claim as new and desire to secure by Letters Patent of the United States, is,-

1. A turbine bucket, the middle portion of which. is. thicker than its edges, said bucket having its base provided with a neck of less width than the bucket and of the same thickness as the. adjoiningportion of the body of the bucket, and horns extending from the base in a direction transverse to a line joining the outer edges of the bucket.

2. A curved turbine bucket the middle portion of which is thicker than its edges, said bucket having its base formed from a neck projecting'from its middle portion and horns on the outer end of the neck extending in a forward and backward direction beyond ,the body of the bucket.

3. A curved turbine bucket the middle portion of which is thicker than its edges, said bucket having its base provided with a neck projecting from said middle portion that is of less width4 than the bucket and horns extending from the outer end of the neck on the concave side of the bucket with their outer faces parallel.

al. The combination with a turbine Wheel having an undercut groove, of a turbine bucket having forwardly extending horns whose outer sides are parallel and whose upper edges lit under the over-hanging portion of said groove.

5. The combination with a turbine Wheel having an undercut groove, ofa bucket provided with holding members which extend along said groove beyond the plane of said bucket and engage the walls of the groove. G. The combination with a turbine wheel having an undercut groove, ofa bucket having horns at its lower endv which extend along said groove.

7. The combination with a turbine wheel having an undercut groove, of a plurality of buckets, each having horns which extend along said groove, and abut against thc next bucket.

8. The combination with a turbine wheel having an undercut groove, of a plurality of buckets each having horns which extend along said groove, and filling between said buckets and between said horns.

9. The combinationwith a turbine Wheel having an undercut groove, of a plurality of buckets each having horns lying in said groove and abutting against the vnext bucket, and fusible material filling the spaces between said buckets.

10. A turbine bucket having a substantially central neck or shank of less width than the portions of the bucket above and below said neck or shank, one of said portions being provided with parallel retaining horns extending 1n a direction transverse to the face of the bucket.

ll.A A curved turbine bucket having a body the middle portion of which is thicker than its edgesa substantially centrally arranged neck projecting downward from the body which is of less Width than the body and has the same thickness and curvature as the corresponding part of said body, and horns extending from each side of the lower end of the neck in a direction transverse to the faces of the bucket.

l2. A. curved turbine bucket having a body the middle portion of which is thicker than .its edges, a neck forming an extension from the middle portion of the bodythat is of less width than said body, and horns projecting from each side of the neck in a direction transverse to the faces of the bucket, the distance between the outer faces of the horns being greater than the `width of the neck.

13. The combination with a turbine wheel having an undercut groove in its periphery, o f buckets having their bases secured in the groove, eachbase comprising a neck which engages the narrow portion of the groove and horns that project from the neck and extend along the groove in engagement with the overhanging walls of said groove.

In witness whereof, I have hereunto set my hand this twelfth day of August, 1907.

ALFRED H. KULIC'H. iVitnesses ALEX. F. MACDONALD, JOHN A. MCMANUS, Jr.