US2677273A

US2677273A - Turbine, compressor, or like rotary machine having a pivoted indicator blade responsive to operating conditions

Info

Publication number: US2677273A
Application number: US67406A
Authority: US
Inventors: Johnson William Evelyn Patrick
Original assignee: Power Jets Research and Development Ltd
Current assignee: Power Jets Research and Development Ltd
Priority date: 1948-01-07
Filing date: 1948-12-27
Publication date: 1954-05-04
Anticipated expiration: 1971-05-04
Also published as: BE486585A; FR978207A; GB641998A

Description

May 4, 1954 W. E. P. JOHNSON TURBINE, COMPRESSOR, OR LIKE ROTARY MACHINE HAVING A PIVOTED INDICATOR BLADE RESPONSIVE TO OPERATING CONDITIONS Filed Dec. 2?, 194a 2 Sheets-Sheet 1 Fig. 2 9 O 6 4 May 4, 1954 w. E. P. JOH ON 2,677,273 TURBINE, COMPRESSO 0 L ROT MACH HAVING A PIVOTED I D CATOR LADE E PONSI TO OPERA co TIO Filed Dec. 27, 1948 2 Sheets-Sheet 2 J5 .4770 NEYS Patented May 4, 1954 DICATOR BLADE RESPONSIVE T O OPER- ATING CONDITIONS William Evelyn Patrick Johnson, Hampstead,

London, England, assignor to Power Jets (Research and Development) England, a British company Limited, London,

I Application December 27, 1948, Serial No. 67,406

Claims priority, application Great Britain January 7, 1948 This invention relates to bladed rotary fluid.- flow machines, such as turbines or compressors, and is primarily concerned with machines in which the fluid-flow is in the axial direction.

One object of the invention is to afford means adapted to respond toan operating condition of the machine, and either to give an indication of variations in such operating condition, or to influence the operation of control means in accordance with such variations.

With this object in view the invention in its broad scope provides a bladed rotary fluid-flow machine such as a compressor or turbine comprising a stationary structure, in part defining a fluid flow passage through the machine, a row of stator blades supported by the said structure and disposed across the passage, a pivot mounting for at least one of the said stator blades, the axis of pivoting extending in the general direction of the machine axis, further mounting means forsecurely holding the remaining blades, an extension of the said movable blade beyond the confine of the passage, and an element abutting the said extension and resiliently opposing movement of the said extension, which element is operable to initiate an external indication of the extent of the said movement, whereby a reading proportional to the fluid forces acting. on the movable blade is obtainable.

The invention may be used to indicate the torque of a turbine (or compressor) and therefore the power delivered or absorbed by integra tion with R. P. M.

For the sake of example, two constructional embodiments of the invention will now be described in greater detail with reference to the accompanying diagrammatic drawings, in which:

Figure 1 is a fragmentary transverse section through an axial flow turbine according to a first embodiment.

Figure 2 is a section on the line II-II in Figure 1.

Figure 3 is a similar view to Figure 1, but showing the second embodiment.

Figure 4 is a section on the line IV-IV of Figure 3.

In the construction shown in Figures 1-2. the casing I of an axial flow turbine carries stator blades, of which only one row is shown. of that row one blade 2 is pivotally mounted on an axis parallel to that of the turbine, while the remaining blades 3 are fixed.

That part of the turbine casing adjacent the row of stator blades shown comprises a pair of

annuli

4, 5, secured in abutting relationship to 6 Claims. Cl. 73-133) each other, and to the remainder of the casing'I,

by suitable axial bolts (not shown). The annuli 4', 5, are formed with complementary recesses 5,

I, which co-operate to form an opening in which the blade 2 is pivotally suspended by a pin 8, and

needle bearings 9. The blade 2 is provided with an outward lever arm extension I0 connected to a suitably-supported piezo-electric pressure element I I forming part of an electrical circuit indil0 cated generally by I2 and which includes an electrical indicating device I3 of any suitable known type.

The tangential component of fluid force on the blade 2 causes slight movement of the blade about its pivot, resulting in deformation of the piezoelectric element II by thelever arm l0, thus in known manner generating in the circuit I2 an E. M. F. which produces at the indicating device I3 a'response proportional to the angular displacement-ofthe blade due to the tangentialcomponent of fluid force. This latter, being proportional to the reaction in the blade-row, is a measure of torque.

To seal a leakage of Working fluid at theblade' pivot a chamber I4. is provided enclosing the lever arm I0 and associated parts.

It is desirable for the .pivot' of the blade to be; so constructed that the internal surface of the fluid passage of the machine is as uninterrupted as is possible, and leakage offluid at'the actual" pivot is reduced to a minimum. To this end the" pivot may, if preferred, be formed by arcuate surfaces at the blade root and complementary surfaces in the casing, as in the construction hereinafter described with reference to Figures 3 and 4.

If desired there may be more than one pivoted blade in a row, or one or more pivoted blades in successive rows. In these latter cases the measuring blades may be commonly connected to one indicator.

In the embodiment shown in Figures 3 and 4 pivotally movable stator blade I5 is secured in the abutting annuli I9, 20 which constitute part of the stator casing and are held together and to the remaining part of the stator casing by axial bolts (not shown). Arcuate surfaces I6 on the root portion of the blade I5 cooperate with corresponding arcuate surfaces formed in the recesses II, I8 provided in the annuli I9, 20. The blade I5 has a lever arm extension l0 which, as in the previous example, is connected to a suitably supported piezo-electric element II forming part of an electric circuit indicated generally by I2 and including an electric indieating device l3, As in the previous example the lever. armfilflxis housed in. a chamber H so as to sealany working fluid which may have leaked between the cooperating surfaces at the blade root.

As before the tangential component of fluid force on the blade l5 causes' deformati'on of the for at least one of the said stator blades, the

axis of pivoting extending in the general direction of the machine axis, mounting means for securely holding the remaining blades of the said row, a chamber external to; thercasing and :posi tioned .in alignment-with"the said pivctable blade, alever arm on said pivotabl e blade extendingbeyond said pivot mounting into said chamber,

and an element supported within the chamberabutting the said zlever arm for opposing resiliently movement of: the said lever arm and.

operable to produce electric Signals which vary in proportionto the lever arm movement, and an electric circuit connected to-said element for transmission of said signals, whereby signals proportional to fluid forces acting on said pivota-ble blade-are obtained;

2. A bladed rotary fluid flow machine as claimed'in claim '1 'andicomprising an indicator in said circuit bymeans of" which earlings of torque 'acting upon said pivotable blade are directly obtained.

'3. A bladed. roan-y fluid flow machine as: claimed in claim 1" and: comprising arcuate sur-- faces-a1; the root of said pivotable blade and complementary surfaces,- to-said arcuate surfaces formed in said casing so as to cooperate togethertoform said pivot-mounting.

4'. A bladed rotary fluid flow machine asclaimed in claim 1 in which said-stationary casing comprisestwoabutting annuli and complementary recesses in the abutting iaces' ofsaid annuli together forming. an apertu're through the casing, and in which the pivot mounting for said pivotableblad'e comprises a needle bearing within the blade-and-a pin passing through said bearing and "extending across said aperture.

5,. Aibladedrntary fluid flowumachine such as a compressor or turbine comprising a stationary casing, in .part' defining an axially-extending fluid flowpassage through themachine, a row-of stator blades mounted inside said casing and disposed across said passage, a pivot mounting for at least one oi said stator blades, the axis of pivoting extending'in the general direction of the machineaxis, mounting means for securely holding theremaining blades of the said row, a chamber external to the casing and positioned in alignment with the saidpivotable blade, a lever arm on said pivotalaleblade extending beyond said pivot mounting into said chamber, a piezoelectric crystal element supported Within the chamber and abutting said lever arm so as to prevent more than limited movement of said leverarm and an electric circuit connected to said element for transmission of signals therefrom-which are proportional to the deformation of the element by lever arm movement, whereby signals proportional itofluidforces acting on said pivotable blade are. obtained.

6. A'bladed rotaryfiuid'flow machine such as a compressor or turbine comprising a stationary the passage, a pivot mounting for at least one of the said stator blades, the axis of pivoting extending in the general direction of the ma-- chine-axis, further mounting means for securely holding the remaining blades, an extension of the said movable blade beyond the confine of' the passage, and an elementabuttingthe said extension andresilientlyopposing movement of the-said extension, which element is operable toinitiate an externalindica-tion of, the extent of the. said movement, whereby a. reading proportional to the fluid forces :acting on the 'movable blade is obtainable.-

- Number Name Date 1,401,668 Brown et a1 Dec. 27, 1921 2,014,684 Junkers Sept. 1'7, 1935 2,173,382 West Sept. 19,1939 2,311,684 Okamura et a1 Feb. 23, 1943 2,378,958v Troller June 26, 1945' 2,388,208 Foss Oct. 130, 1945. 2,409,837 Alford Oct. 22, 1946; 2,460,778 'Willgoos Feb..1, 1949 2,477,954 Blanc Aug. .2, 1949