US1345674A - Elastic-fluid turbine - Google Patents

Description

F. HODGKINSON.

ELASTIC FLUID TURBINE- APPLICATION FILED JAN- 30. 1915.

IN VE N TOR.

HIS ATTORNEY IN FACT luuiran stares PATENT tJE-FIQE runners nonen nson, or snenwocn PARK,PENNSYLVA1\TIA, assienoa are when menousnnnncrnrc a MANUFACTURING COMPANY, a coaronarion or rennilti measure,

ELASTIC-FLUID TURBIJEIE.

' atcntedJuly (i, ltltith Application filed January 30, 1915. Serial No. 5,249.

lie it known that 1, Francis l-looeninson,

a subject the liing of Great Britain and ciency of turbines by reducing losses caused by the productionof eddy currents in the fluid passages between the separate stages or sections of the turbine.

lurbines of the reaction type, are usually built in more than one diameter, and it is.

desirable that the fluid passages between the working sections of different diametersbe soarranged as to provide an easy passage for the fiuid without the production of objectionable countencurrents oreddies and resultant losses in f, efliciency i Such fluid passages are located between the rotor and the stator elements and in turbineshaving high blade speeds, in which the blades are carried, for example, on disks or wheels, it is impossible to construct a rotor element having the necessary contour to provide fluid passages of the desired shape, without materially increasing the weight of the rotor element. It will also be apparent that the outer surface of the turbine rotor built up to form portions of different diameters cannot be constructed to provide a smooth and continuous surface between the working passages of different diameters without materially changing the rotor construction and adding materially to the weight of the rotor.

in accordance with my invention, ll form fluid pas ages between the separate sections or stages of the turbine which are wholly located within stationary members and,

which, in the present embodiment of the invention, are shown mounted 011 the stator element of the turbine.

In the single sheet drawing accompanying and forming a part hereof, Figure 1 is a fragmental longitudinal section of a turbine equipped with stationary fluid passages for delivering the motive fluid from sections of the working passage of smaller diameter to sections of larger diameter.

, Fig, 2 is a transverse section through a stationary fluid passageon a smaller scale.

Referring to the drawing: T he rotor element illustrated consists of a cylinder 3, bolted or otherwise secured to a wheel a, which as shown, is formed integrally with a drum 5, on which two wheels 6 and 7 are mounted. The peripheral face of the cylinder 3,011 which the blades or buckets 8 are mounted, is of less diameter than the blade carrying rim 9 of the wheel fl, and this rim is of less diameter than the blade carrying rims 10 of the wheels 6 and 7. Consequently, the portion of the rotor element shown, is equipped with three sets of blades, each of whlch iorms a separate working section of the turbine of diiferent diameter from the other two.

The stator 11 inclosing the rotor is of I usual construction and is formed in two sections, as is customary. lts inner face corresponds generally to the contour of the turhine," rotor and is of such diameter to pro recting vanes 12 are located. Inasmuch as the stator increases in diameter from the admission end of the turbine to the exhaust end and, inasmuch as the working blades of the turbine increase in length toward the exhaust end of the turbine but are arranged in groups including several rows of blades or vanes of the same length, it is customary to increase the diameter of the stator in steps corresponding somewhat to the step formation of the rotor.

In turbines having high blade speeds practice indicates the advisability of mounting the blades on wheels or disks, since such a constiuiction provides the necessary strength without unduly increasing the weight of the rotor element. Rotors constructed in this manner with wheels or disks of different diameters form pockets or sharp ion the other in which there are no pockets or sharp turns capable of producing retarding or eddying currents in the motive fluid.

In the present embodiment of the inventionthese passages are formed in separate annular members 13, which, as shown, are bolted or otherwise secured to the stator and are formed in sections corresponding to the sections of the stator. Each member 13 is provided with an annular fluid passage let, which is adapted to receive motive fluid issuing from the blades of one section and to direct it into the blades of the next adjacent section. The annular inlet to the passage A may be of less diameter than the outlet and the walls of the passage are curved so as to direct the fluid to the section of larger diameter with minimum losses due to friction or reversal in flow. As illustrated, the inner wall 15' of the passage is secured to the outer wall by means or" radially extending webs 16, which are preferably located so as to conform to the direction of flow ot the steam through the passage.

In other words, the webs 1.6 will be so located that they will be substantially parallel to the direction of flow of the steam or motive fluid issuing from the last row of blades delivering steam or fluid to the passage 2-1. As illustrated, the member l3 is so formed that its outer wall in effeet forms a continuation of the inner surface of the stator between the portions of different diameters, and the inner wall in effect forms a continuation of the peripheral face of the rotor between portions of different diameters, a small clearance only being maintained between it and each adjacent portion of the rotor.

It will be apparent that these passages .14 may be formed within the stator element and that various changes, modifications, substitutions, additions and omissions may be made in the apparatus illustrated without departing from the spirit and scope of my invention.

\Vhat I claim is:

A fluid conduit member for turbines having spaced rotor elements, comprising a pair of concentrically disposed stationam annular walls adapted to fit between the rotor elements, and having their outsile surfaces conforming in contour to their inside. surfaces, and having their inside surface curved to form a passage oll'ering minimum resistance to the flow oi fluid from one rotor of small diameter to a rotor oi larger diameter, the outer wall of the said member being provided with a radially extending flange whereby the member is secured to the turbine stator and the inner wall being connected to the outer wall by fluiil directing vanes whereby the inner wall is supported by the outer wall.

In testimony whereof l have hereunto subscribed my name this 21st day of January, 1915.

FRANClS HODGKINSON.

itnesses (J. V. MeGrinm, it. M. MoGALLrsTER.

Images