Radiant energy – Photocells; circuits and apparatus – With circuit for evaluating a web – strand – strip – or sheet
Patent
1994-08-15
1996-11-05
Westin, Edward P.
Radiant energy
Photocells; circuits and apparatus
With circuit for evaluating a web, strand, strip, or sheet
25055914, 250237R, 250214PR, 356386, G01N 2186
Patent
active
055720390
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to the observing of the magnitude of an axial gap between relatively rotating parts in a fluid flow engine.
SUMMARY OF THE INVENTION
The invention has particular efficacy when used to observe the running clearance between, say, fixed stators and rotating turbine blades and between blade shroud fins and a casing surrounding them.
According to the present invention a method of observing a gap between relatively rotating parts comprises connecting first and second radiation transmitting members to a fixed part of a turbine, the first and second members being in a spaced relationship and are arranged so that the members protrude towards an opposing face of a rotatable part of the turbine, the first and second members being adapted and aligned relative to one another to direct a beam of radiation from the first transmitting member to the second transmitting member, positioning a projection on said opposing face to ensure passage thereof between the first and second members during rotation of the rotatable part, measuring the amount by which the beam of radiation passing between the first and second members is obscured by the projection so as to provide an indication of the magnitude of the gap.
The invention further provides apparatus for effecting the method. Apparatus fixed in a turbine comprises first and second radiation transmitting members which are connected in spaced relationship to a fixed part of the turbine so that the members protrude towards an opposing face of a rotatable part of the turbine, the first and second members being adapted and aligned relative to one another to direct a beam of radiation from the first transmitting member to the second transmitting member characterised in that a projection is positioned on the opposing face to ensure passage thereof between the first and second members during rotation of the rotatable part, means being provided for measuring the amount by which the beam of radiation passing between the first and second members is obstructed when the projection on the opposing face of the rotatable part of the turbine passes between the members.
The invention will now be described, by way of example and with reference to the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic, axial cross sectional view of an array of fixed stators and rotatable turbine blades, incorporating an embodiment of the present invention.
FIG. 2 is an exploded view of one embodiment of radiation beam reflecting means in accordance with the present invention and
FIGS. 3, 3A, 4, 4A, 5, 5A, 6, 6A, 7, and 7A depict various beam obsuring features which enable signals to be extracted when applied to the embodiments of FIGS. 1 and 2.
FIG. 8 depicts an alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1. A turbine 2 includes a casing 4 in which two stages of stator blades 6 and 6a are fixed via their outer ends.
A first stage of blades 8 lies immediately downstream of the stator stage 6 and a second stage of blades 8a lies immediately downstream of stator stage 6a.
Both stages of blades 8 and 8a are carried in a drum for rotation about an axis 12.
The blades 8a have shrouds 12a at their outer ends in known manner. Each shroud 12a has an axially directed fin, 14a extending towards the opposing face of roots 16a at the outer ends of stators 6a. The fins 14a together provide an annular seal against massive egress of fluid from the turbine annulus 18.
It is known to provide fins of the kind described herein for the stated purpose. Such arrangements however, have drawbacks, e.g. the fins can have their sealing efficiency destroyed as a result of excessive rubbing against the opposing face of the stator roots. In the present example therefore, the blades 8 are modified, which modification, in conjunction with a device 20 to be described hereinafter, enables the observation of the changes in the gap between the extremity of the fins 14 and the opposing face of t
REFERENCES:
patent: 3859617 (1975-01-01), Oka et al.
patent: 3908444 (1975-09-01), Peter
patent: 4021119 (1977-05-01), Stauffer
patent: 4049644 (1977-09-01), Wennerstrom
patent: 4114035 (1978-09-01), Herzog
patent: 4180931 (1980-01-01), Osch
patent: 4284885 (1981-08-01), Swensen
patent: 4584510 (1986-04-01), Hollow
patent: 4716942 (1988-01-01), Jensen et al.
patent: 4812635 (1989-03-01), Kaufmann et al.
patent: 5079432 (1992-01-01), Miller
NTIS Tech Notes Feb. 1988, Springfield, VA US p. 100, XP2538 `fibre optic lateral displacement sensor`.
Jenkins Michael P.
Sweeney Michael
Calogero Stephen
Rolls-Royce Power Engineering plc
Westin Edward P.
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