BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a jet engine as known in the prior art.
FIG. 2 shows a portion of a structure for adjusting the cross-sectional area of a nozzle.
FIG. 3 shows a portion of a liner attachment as known in the prior art.
FIG. 4 shows an improved liner attachment.
FIG. 5 is an exploded view of a convergent flap and seal along with the liner attachments.
FIG. 6 is an exploded view of the improved flap liner attachment.
FIG. 7 is an exploded view of the improved seal attachment.
FIG. 8 is an exploded view of the seal.
FIG. 9 is an exploded view of the flap.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a gas turbine engine 10. As known, a fan section 11 moves air and rotates about an axial center line 12. A compressor section 13, a combustion section 14, and a turbine section 15 are also centered on the axial center line 12. A nozzle section of the turbine discharges gas downstream. A convergent section 36 leads into a throat and a divergent section 31 leads away. FIG. 1 is a schematic view, however, it does show the main components of the gas turbine engine.
FIG. 2 shows a prior art structure to change a cross-sectional area of the nozzle. As known, an actuator 34 drives a piston to cause the divergent section 31 and the convergent section 36 to pivot to change the cross-sectional area of the throat between the two. This structure is shown schematically, and may be as known in the art.
As shown at 36, convergent flaps and seals extend from a pivotal connection to the divergent section 31, and upwardly to a housing 37. This structure prevents hot gasses from an area 39 inward of the convergent section 36 from reaching a housing 41 housing the linkages and actuator 34. As known, a liner 38 faces the hot gas, and provides some thermal protection for the flap and seals 36.
As shown at 38 in FIG. 3, in the prior art, this liner included a plate 40, a separate dam 42, and rivets 44 attaching the plate 40 to an underlying plate 43.
A bracket 46 includes an opening 48 to secure the liner 38 to the flap or seal. In addition, a lower surface 50 of the bracket 46 is welded at 51 to the plate 43 along its entire length. A forward portion 52 of the bracket 46 extends beyond the dam 42. As known, the dam 42 provides a pressure differential between an upstream area forward of the dam 42, and a downstream area adjacent to the bracket 46.
As explained above, in this prior art structure, an upstream end 54 of the bracket 46 is cooler than a downstream end 56. Thus, there is a thermal gradient along the lower surface 50 and the weld joint 51. This causes stresses and other challenges. The prior art has addressed these challenges by forming the bracket 46 out of materials such as columbium, which have low coefficients of thermal expansion (CTE). However, recently, it has become desirable to have more freedom in the material selected for the bracket 46. In one bracket, it is desirable to use INCO 625, which has a relatively high CTE.
As shown in FIG. 4, an inventive liner and bracket assembly 60 includes a pair of forward plates 61 and 62. A leg 64 on the rear plate 62 extends rearwardly. Another plate 65 has a rear face 66 abutting faces 68 and 69 from the plates 61 and 62. As shown, a rivet 70 connects the three plates. Features with regard to this structure can be best understood from co-pending patent application entitled “Axially Split Nozzle Liner for Convergent Nozzle,” filed on even date herewith and assigned Ser. No. ______.
The improved bracket 72 has spaced legs 74 and 75 along with an intermediate notch 76. A second pair of legs 74 and 75 is on the opposed end of the bracket. Rivets 78 secure the bracket 72 to the plate 65. Due to the notch 76, there are axially spaced legs 74 and 75, which contact the hot plate 65, reducing the footprint or contact area compared to the prior art. Notch 76 results in an area spaced away from the hot plate 65. Now, when the downstream end of the bracket is subjected to greater heat than the upstream end, the spaced legs can allow some adjustment, such as by the leg 75 expanding away from the leg 74, but with the expansion being compensated for within the notch 76.
Further, the inventive bracket 72 will provide some circumferential adjusting ability also due to the rivet connection at 78.
As shown in FIG. 5, an 38 secures the liner and bracket to an underlying convergent flap 83. As known, an opening 184 in the flap 83 receives a bolt 86 through the opening 84 in the bracket 72. A washer 88 and nut 90 secure the bolt. The opening 184 in the flap 83 has spring fingers 92 which serve to hold the washer 88 during assembly. Features of this structure can be best understood from the co-pending application entitled “Quick Change Fastener System for Attaching Liner Bracket to Convergent Flap and Seal in Turbine Nozzle,” filed on even date herewith, and assigned Ser. No. ______. The structure of the liner and bracket as shown in FIG. 5 is the prior art structure. This view is intended to provide an understanding of how the combined liner and bracket assembly is attached to the flap or seal. However, the quick change coupling is inventive to this application.
A similar bracket and liner arrangement 161 has backing plate 165, and is attached to a seal 81, again through an arrangement similar to that shown with regard to the flap 83.
FIG. 6 is an exploded view of the liner and bracket assembly 60. As can be appreciated, the bracket 72 is positioned on the plate 65. The rivets 70 secure the plates 61, 62 and 65. An alternative rivet arrangement is disclosed in the co-pending patent application entitled “Thermally Compliant Rivet Connection for Connecting Turbine Engine Liner to Convergent Flap and Seal for Turbine Nozzle,” filed on even date herewith and assigned Ser. No. ______.
The plate 65 has a turned in end 100. FIG. 7 shows the similar liner and bracket assembly 261. In general, the difference is that the plate 165 has a more complex, turned in end 166.
FIG. 8 shows an exploded view of the components of the liner and bracket 261 to the convergent seals 81. FIG. 9 shows a similar exploded view of the components of the bracket and liner 60 being attached to the convergent flap 83.
Although a preferred embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.
Patent Application
20080078163
