US853334A - Turbine-vane. - Google Patents

Description

No. 853,334. PATENTED MAY 14, 1907.

' c. A. BAGKSTROM'.

TURBINE VANB.

APPLICATION FILED 001'. 24.1904.

1' 6 INVENTOR ATTORNEY! WIINESS5= 6 i UN TED sTA Es PATENT OFFICE.

- CHARLES A. BACKSTROM, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO BACK- line of the series.

' for casting, the interior portion of the vane beportion of a running wheel with the vanes in STROMSMITH STEAM TURBINE & PORATION WISCONSIN.

MANUFACTURING COMPANY, A COR- TURBINE-VANE- Specification of Letters Patent.

Patented May 14, 1907.

Be it known that I, CHARLES A. BACK- sTRoM, a citizen of the United States, residing at Milwaukee, county of Milwaukee, and State of Wisconsin, have invented new and useful Improvements in Turbine-Vanes, of which the following is a specification.

My invention relates to improvements in I turbine vanes.

The objects of my invention are to secure absolute uniformity and accuracy in the contour of the vanes as well as in their position in the running wheel, and to avoid the necessity of finishing and she ing the surfaces of the vanes by machine tools. Also to providefor casting the vanes in a set or series of connected vanes which may be unitedly secured in position in the running wheel, thus avoiding-the labor of assembling the vanes separately and dis ensing with numerous rivets.

A further 0 ject of my invention is to pro.- vide the vanes with exterior shells of smoother and harder material than that ordinarily used To all, whom it may concern: I

mg composed of softer material which, however,is integrally united to the hard outer shell. In the following descri tion reference, is had to the accompanying awings in which Figure 1 is a View 'of a series of vanes ready for insertion in a running wheel. Fig. 2 is a peripheral view of the same with two of the vanes partially broken away along the center Fig. 3 is a transverse sectional view drawn on line XX of Fig. 1. Fig. 4 is an end view of one of the shells showing the edges of the curved walls. Fig. 5 is a similar view showing a modified form of construction. Fig. 6 is a view of the concave side of a shell such as is shown in Fig. 5. Fig. 7 is a plan view of a portion of the mold, with the cope partially broken away to show the upper ends of shells similar to those shown in igs. 5 and 6. Fig. 8 is a vertical sectional view of the mold, drawn transversely to a row of shells. Fig. 9 is a sectional view of a position.

Like parts are identified by the same reference characters throughout the several views. The drawings are illustrations of the construction of vanes designed for use in an impulse turbine arranged for inward-radial attack, and the vanes 1 are to be mounted between disks 2 which constitute the sides of a running wheel as shown in Fig. 8. In constructing these vanes, a series of shells are formed, preferably by stamping them from sheet metal, such as nickel-steel, and each shell, in the construction shown, is rovided I with an end wall 3 and two curve walls 4 and 5, the inner faces of which constitute finished concave and convex surfaces of the bucket .cavities when the vanes are com-' pleted. The walls 4 and 5 may, if desired, be extended in the form of wings 6 and 7 on each side and the space between these wings, if used, and the walls 4 and 5, is filled with a core of molding sand or other suitable material. A mold is then prepared, having a curved channel in which the shells are placed in a row with the walls 4 of one shell abutting the walls 5 of the next at the side edges and with open cavities 11 between the divergent central portions of these walls. The space between the walls 4 and 5 of each shell constitutes a bucket cavity in the com leted series of vanes and in the mold. Tliis cavity is covered by the wall 3. The cope is then prepared with a channel 10, corres onding ln'position with the row of shells, an molten metal is then flowed into this channel 10 to fill it, and the cavities'll between theshells,

under conditions of temperature to cause it to fuse with the shell surfaces with which it contacts. On removing the casting with the shells thus integrally connected, the vanes are completed by merel trimming off the edges, or thawings 6 an 7 if such wings are employed. The walls 4 and 5 of each shell form the concave wall of one vane and the convex wall of the-next succeeding vane.

. The object of the wings 6 and 7 is to keep the molten metal from entering the bucket cavities where the cores are imperfect, but if the molds and cores are carefully prepared, the wings may be dispensed with and the work of trimming the edges of the vanes lar ely if not entirely avoided.

l the vanes thus produced in a single casting operation. are inte rally connected and held in position by the in of cast metal which filled the channel 10 in the mold, and

this bar ma be "formed to fit a channel 15 in one of the isks 2 of the running wheel, thus accurately determining the position of the vanes and facilitating their attachment to the disks.

It will be understood that while I have shown and described the invention with reference to a s ecia'l form of turbine, it may be adapted to t e'requirements of any style of turbine, and, if desired, the connecting bars may be'formed at both ends of the vanes, or

the vanes may be separately formed, or connected in series, having any desired number.

-By stamping the surface walls of the vanes from sheet metal, absolute uniformity and accuracy 1s insured in any case, and the vanes are rovided With smooth hard surfaces who require no finishing.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is,r

' 1.. A turbine vane having a stamped exterior surface of relatively hard material and a filling of cast metal between the surface walls, 1

2. A cast metal turbine vane provided 3. A series of turbine vanes integrally surface of stamped metal fused to the cast metal interior.

ing-bar, each vane being surfaced with metal of a diiferent character from that composin the bar, and connected with the bar throug projections on the latter extending between the surface walls.

5. A series of turbine vanes havin body portions of cast-metal formed integrally with a curved metallic eonnectin bar and having surfaces of different materia froni that composing the bodyortions. r

in the presence of two witnesses.

CHARLES A'. BACKSTROM.

Witnesses: I

JAB. B. ERWIN, LEVERETT 0. WHEELER.

, 45 In testimonyw ereof I' aflix'my signature

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