Low profile vane retention

Patent metadata

Field	Value
Publication number	US-9506361-B2
Application number	US-201313789756-A
Country	US
Kind code	B2
Filing date	Mar 8, 2013
Priority date	Mar 8, 2013
Publication date	Nov 29, 2016
Grant date	Nov 29, 2016

Abstract

A gas turbine having an annular casing with a series of circumferentially spaced openings defined therethrough; a plurality of vanes extending radially inwardly though respective casing openings, an outer end of the vanes projecting radially outwardly from the casing through the respective openings and located within the respective openings by grommets, and an inner end of the vanes being mounted to an inner portion of the casing; a flexible, segmented strap extending around the annular casing, surrounding the projecting outer ends of the vanes; and a spring radially loading the flexible strap configured to apply a tension force to the flexible strap.

First claim

The invention claimed is:

1. A gas turbine engine having an annular casing with a series of circumferentially spaced openings defined therethrough; a plurality of vanes extending radially inwardly through respective casing openings, an outer end of the vanes projecting radially outwardly from the casing through the respective openings and located within the respective openings by grommets, and an inner end of the vanes being mounted to an inner portion of the casing; a flexible, segmented strap extending around the annular casing surrounding the projecting outer ends of the vanes; and a spring strip surrounding the plurality of vanes and positioned radially between the flexible strap and the vanes to press radially against the respective flexible strap and vanes wherein the segmented flexible strap is in the form of a plurality of segments joined end to end by clasps, and wherein the clasps each have a web portion and a securing means near each end of the web to engage a respective segment end wherein the segment end is provided with mating means to be engaged by the securing means of the clasp.

2. The gas turbine engine as defined in claim 1 wherein each segment has a laterally extending bead at each end thereof with a reverse hook formed therein for receiving the clasp.

3. The gas turbine engine as defined in claim 1 wherein each segment has a laterally extending bead at each end thereof with an eyelet extending axially thereof.

4. The gas turbine engine as defined in claim 2 wherein each bead has an eyelet extending axially thereof.

5. The gas turbine engine as defined in claim 2 wherein each clasp has a web and a reverse hook formed at each end of the web to matingly engage the reverse hooks at the beads.

6. The gas turbine engine as defined in claim 3 wherein the clasp comprises a web with bead engaging means at each end thereof and a pair of separate C-shaped spring wires adapted to engage the respective eyelets in the beads and trap the web of the clasp.

7. The gas turbine engine as defined in claim 4 wherein the clasp comprises a web and a reverse hook formed at each end of the web to matingly engage the reverse hooks at the beads and a pair of separate C-shaped spring wires adapted to engage the respective eyelets in the beads and trap the web of the clasp.

8. The gas turbine engine as defined in claim 1 wherein the spring strip comprises an elongated web in the form of a circumferential ring and a plurality of laterally extending spring fingers projecting over the web in an alternating and crossing fashion from either edge of the web.

9. A gas turbine engine having an annular casing with a series of circumferentially spaced openings defined therethrough; a plurality of vanes extending radially inwardly through respective casing openings, an outer end of the vanes projecting radially outwardly from the casing through the respective openings and located within the respective openings by grommets, and an inner end of the vanes being mounted to an inner portion of the casing; a flexible strap extending around the annular casing surrounding the projecting outer ends of the vanes; the improvement comprising a spring strip surrounding the plurality of vanes and positioned radially between the flexible strap and the vanes, the spring strip including an elongated web in the form of a circumferential ring and a plurality of laterally extending spring fingers projecting over the web in an alternating and crossing fashion from either edge of the web to press radially against the respective flexible strap and vanes.

10. The gas turbine engine as defined in claim 9 wherein the web engages the vanes while the spring fingers engage and apply tension to the flexible strap.

11. The gas turbine engine as defined in claim 9 wherein the web engages the flexible strap while the spring fingers engage the casing and the vanes.

12. A vane retention apparatus for retaining an array of radially extending stator vanes arranged and protruding from an annular casing in a gas turbine engine; comprising a flexible, segmented strap extending around the annular casing surrounding the vanes; and a spring strip surrounding the plurality of stator vanes and positioned radially between the flexible strap and the stator vanes to press against the respective flexible strap and stator vanes wherein the flexible strap is in the form of a plurality of segments joined end to end by clasps, and wherein each segment has a laterally extending bead at each end thereof with a reverse hook formed therein for receiving one of the clasps and each bead has an eyelet extending axially thereof.

13. The vane retention apparatus as defined in claim 12 wherein the clasp comprises a web and a reverse hook formed at each end of the web to matingly engage the reverse hooks at the beads and a pair of separate C-shaped spring wires adapted to engage the respective eyelets in the beads and trap the web of the clasp.

14. A vane retention apparatus for retaining an array of radially extending stator vanes arranged and protruding from an annular casing in a gas turbine engine; comprising a flexible strap extending around the annular casing surrounding the vanes; the improvement comprising a spring strip surrounding the stator vanes and positioned radially between the flexible strap and the stator vanes, the spring strip including an elongated web in the form of a circumferential ring and a plurality of laterally extending spring fingers projecting over the web in an alternating and crossing fashion from either edge of the web to press radially against the respective flexible strap and stator vanes.

15. A method of retaining vanes in a gas turbine engine case, the case having a plurality of slots circumferentially distributed therearound, the vanes extending radially through each slot such that an end of the vane projects outwardly from the slot, the method comprising steps of placing a circumferentially continuous spring strip to surround the vane ends; placing a flexible strap made of a plurality of strap segments around the spring strip; and joining the ends of the strap segments by using respective clasps having a web portion and securing means near ends of the web portion to engage with mating means provided on the respective ends of the strap segments, to provide a continuous strap wrapped around the circumferentially continuous spring strip such that the spring strip presses radially outwardly against the flexible strap and radially inwardly against the respective vanes in position.

Assignees

• Pratt & Whitney Canada

Inventors

• Fielding Bruce
• Tomes Nathan
• Veitch Thomas

Classifications

• F05D2260/12

  Testing on a test bench · CPC title

• Y10T29/4995

  Nonthreaded · CPC title

• F01D25/246

  Fastening of diaphragms or stator-rings · CPC title

• F01D9/042 Primary

  fixing blades to stators (fixing stator-rings in the casing or to each other F01D25/246) · CPC title

• F01D9/041 Primary

  using blades (F01D5/148 takes precedence) · CPC title