US908685A - Radial turbine. - Google Patents

Description

B. LJUNGSTRM.

RADIAL TUBBINE.

APPLICATION FILED APRA, 1907.

Patented Jan. 5, 1909.

PATENT orrron.

BIRGER'LJUNGSTRM, OF STOGKHOLM,SWEDEN. i

RADIAL TURBINE.

i I Specification of Letters Patent.

Patented Jane, 1909.

applicaties nea Api-u 4, 1907. 'serial No. 366,344.

To all whom it ma/y concern:

Be it known that I, BIRGER LJUNGSTRM, a subject of the King of Sweden, residingat 8 Flemminggaten, Stockholm,--Swed.en, have invented certain new and useful Im rovements in Radial-'Flow Turbines, of whlch the following is a specication'.- j

This invention has for its object to provide means for balancing the axial thrust upon the rotor of a turbinewhen under the actionv of the pressure medium. j

In order to carry out the purposes of this invention `a baffling device of s ecial conside of the same.

struction has been made use of W ich by being positioned upon those faces of the vane supporting disks' op osite to the faces upon which the vanes t emselves are secured,

brings about a compensation inthe pressures wherebyl the pressure upon one side of said rotating vane-supporting disk is automatically regulated to balance that on the other In furtherance of this object, it is of importance-that the arrangement of the baffling device should be self-regulating so as to meet the requirements placed upon it when working under either constant steam pressure or under sudden alterations in the same, such as occurs when the admission of steam to the vanes is brought about in greater or less degree. To attainthese re- .sults the bafliing means are arranged in suitable casings in directicommunication with the ring-shaped interspaces between the vanesupporting disks.

In the accompanying drawin s, Figure 1 is a sectional view of a radial ow turbine showing one embodiment of my invention; Fig. 2is a view-also in section showing another embodiment of my invention; Fig. 3 is a view in section, of an embodiment of my invention in which there are two op ositely rotating shafts each provided with) pressurebalancing vanes; Fig. 4 is a view in section of still another embodiment; and Fig. 5 is a view in section of another embodiment in which the baiing device is shown incased in an elongated portion of the casing.

Referring nowto the accom anying drawings in which like characters re er to the same parts wherever used, in Fig. 1, is shown the turbine casing b carrying upon the interior wall thereof, a series of iixed Vanesal while u on the rotor shaft dis secured a disk e upon w 'ch are mounted a series of rotating vanes c. Upon the back of said disk e are mounted a sel'ies of bafliing rings f which in conjunc- E tion with a series of similar rings `secured to the back wall lof casing b lafford a ready means of'balancing the axial thrust from the How of steam through blades or vanes a and c.

Piercing the disk care a number of regularly interspersed holes or channels g which serve for the passage of the pressure medium from the blade-containing chamber to the labyrinth rings in the rear whereby the compensation in pressures is effected by the inter-disposition of said rings. These rings are mounted in such manner as to cause the outer edge of each ring to project over into the space between the two adjacent and opposite rings thereby adapting the labyrinth .to permit a slow passage of steam therefthrough. To insure a minimum v loss of steam the labyrinth rings are mounted to have the smallest degree of play consistent with smooth running.

In Fi 2 will be seen a modification of the device (Fescribed above, while constructed on the same general principle, it will be noticed that the baffling device has been placed between the back wall ofthe turbine and aplate h connected to the-plate `carrying the vanes c. In this embodiment communication between the lblade-containing 'and labyrinth chambers is effected by means of a plurality of tubes or pipes i.

Referring now to Fig. 3 there is shown a air of conical blade-su orting plates j and carrying two series of i; ades a and c which are made longer as their distance from the rotor-shaftsl and m increases. Since in this embodiment both shaftsv are rotatin ,it becomes necessary to have a series of affling rings for each rotor having the same general arrangement and connections as described above with the exception that in this case the casing of the turbine is better adapted to` be cast in halves with aparting lane through the axis of the shaft. This is acilitated by the method of setting up employed which consists in first introducing the rings into the casing'loosely and afterwards tighteningthe same therein.

Referring now to Fig. 4, the vane-supporting disks will be seen to be made up of a number of concentric'annular fiat surfaces offset `one from the other outwardly as the f near the periphery of the rotor. AThe bla e-supporting plates as well as the walls of the casing, are by this construction formed with a step-like coned surface which while aiiording the greater strength in a direction along the lll' axis, at' -the same time makes it possible to maintain a uniform radial arrangement of the ballling rings. In the arrangement of the thrust counterbalancing device upon the outer surfaces of the vane-supporting plates,

a pressure is maintained upon said plates in f such a direction as to ho d them together against the pressure tending to spread them apart. In Fig. 5 is shown an embodiment of my invention in which the baffling device is not placed within the casing b proper but in a specially constructed chamber 0 oli'set from casing b and communicating therewith by means of a connecting pipe. bodiment the vanes and rings while they are mounted in separate casings, will be seen to besubject to the same general principles'as the foregoing embodiment since a single Lshaft serves to mount both.

Having thus described my invention what I claim is:

1. In a radial Ilow turbine, the combination with a housing, two rotor shafts coaxially mounted within said housing, a disk carried on each rotor shaft, and blades proj ecting from each of the adjacent faces of said disks in such manner as to cause rotations of said shafts in opposite directions ,'of pressure receiving surfaces having substantially equal areas with the areas covered by the blades, each of said surfaces being oppositelyfaced to the blade-bearing surfaces with which it rotates; means for leading the pressure medium from in and about the blades to each of said surfaces opposed thereto; and a plu- In this em! rality of concentriclabyrinth rings projecting 2 from each of said pressure-receiving sui-, faces and housing wall ad]acent thereto, sald f rings overlapping each other in such manner as to form a circultous passage for the pressure medlum whereby pressure 1s created and l l i l applied to compensate the axial thrust ofthe blades.

2. In a radial flow turbine of the type oescribed, the combination With va housing and o positely rotating rotors mounted Within t e housing; of ya substantially cone-formed blade-bearing disk forming a part of each of said rotors, blades mounted on the conveXed surface of said disk; concentric labyrinth ring mounted in the concaved surface of the disk; a plurality of perforations in said disk whereby the pressure medium is conveyed from the bladed surface to the ring-bearing l surface; and a plurality of labyrinth rings connected with the wall ofthe ousing and adapted to form a running joint with the rings carried by the disk in such manner as to check the passage of the pressure medium,

ywherebypressure is created upon the pressure-receiving surface-of the disk to compensate the axial thrust of the bladed surface.

3. In a radial ow turbine of the type described, the combination with a housing, of a rotor mounted in the housing said rotor comprising a blade-bearing face, a ring bearing face opposed thereto, passages for conveying .the pressure medium from action upon one of said faces to action upon the other of said faces, anda ring-bearing surface carried by the housing and in conjunction with the rotor ring-bearing surface, forming a circuitous passage for the pressure medium whereby an opposite and compensating pressure is caused to react against the axial thrust on said blade-bearing surface.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

, BIRGER LJUNGSTROh-.

l/Vitnesses l CARL FRIBERG, E. RBERG.

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