Abstract:
A nozzle guide support device, that supports a nozzle guide of a fuel nozzle on an open flange part encircling a fuel supply hole of a combustor of a gas turbine engine, is foamed by fixing a cap that supports the nozzle guide in a floating state to the open flange part by means of a rivet. Rotation of the nozzle guide relative to the open flange part is restricted by engagement between a recess portion of the nozzle guide and a spacer fitted to the rivet. Accordingly, not only is it possible to cut production time and production cost compared with a case in which the nozzle guide support device is fixed by welding or brazing, but it is also possible to suppress unlimited rotation of the fuel nozzle guide while enabling the fuel nozzle guide to float in a radial direction and a axial direction.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0001]    The present invention relates to a structure for supporting a nozzle guide of a gas turbine engine in which a nozzle guide of a fuel nozzle is supported in a radially and axially floating state on an open flange part encircling a fuel supply hole formed in a combustor of the gas turbine engine by nozzle guide support means. 
       Description of Related Art 
       [0002]    Such a structure for supporting a nozzle guide of a gas turbine engine is known from Japanese Patent Application Laid-open No. 4-244513. This invention enables a constant amount of air to flow in a gap between a support plate  50  (open flange part) and a fuel injection nozzle  32  (fuel nozzle) fitted into a ferrule  58  (nozzle guide), even when the fuel injection nozzle  32  moves relative to the support plate  50 , by welding a retaining plate  74  (cap) to extremities of elliptical flanges  70   a  to  70   d  projectingly provided on the support plate  50  encircling a dome inlet  28  (fuel supply hole) of a combustor  10  and by supporting the ferrule  58  in a floating state in a space formed between the support plate  50  and the retaining plate  74 . 
         [0003]    However, the above arrangement not only has the problem that production time and production cost are high because the retaining plate  74  is welded to an entire periphery of the flanges  70   a  to  70   d  of the support plate  50  encircling the dome inlet  28  of the combustor  10 , but there is also a possibility that, since rotation of the ferrule  58  relative to the support plate  50  is prevented by fitting the elliptical ferrule  58  into an interior of the elliptical flanges  70   a  to  70   d  of the support plate  50 , the rotation-preventing structure will increase in size to thus become a main cause for an increase in weight. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention has been accomplished in light of the above circumstances, and it is an object thereof to support a nozzle guide on an open flange part of a combustor in a simple manner and to reliably prevent rotation of the nozzle guide relative to the open flange part. 
         [0005]    In order to achieve the object, according to a first aspect of the present invention, there is provided a structure for supporting a nozzle guide of a gas turbine engine in which a nozzle guide of a fuel nozzle is supported in a radially and axially floating state on an open flange part encircling a fuel supply hole formed in a combustor of the gas turbine engine by nozzle guide support means, wherein the nozzle guide support means is fixed to the open flange part by swage-joining, and rotation of the nozzle guide relative to the open flange part is restricted by engagement between a recess portion provided in the nozzle guide and a projecting part provided on a swaged member of the nozzle guide support means. 
         [0006]    In accordance with the first aspect, the nozzle guide of the fuel nozzle is supported in a radially and axially floating state on the open flange part encircling the fuel supply hole formed in the combustor of the gas turbine engine by the nozzle guide support means. Since the nozzle guide support means is fixed to the open flange part by swage-joining, and rotation of the nozzle guide relative to the open flange part is restricted by engagement between the recess portion provided in the nozzle guide and the projecting part provided on the swaged member of the nozzle guide support means, not only is it possible to cut production time and production cost compared with a case in which the nozzle guide support means is fixed by welding or brazing, but it is also possible to suppress unlimited rotation of the fuel nozzle guide while enabling the fuel nozzle guide to float in the radial direction and the axial direction. 
         [0007]    According to a second aspect of the present invention, in addition to the first aspect, a plurality of the nozzle guide support means are disposed at predetermined intervals in a circumferential direction of the open flange part. 
         [0008]    In accordance with the second aspect, since the plurality of nozzle guide support means are disposed at predetermined intervals in the circumferential direction of the open flange part, it is possible to cut total weight of the nozzle guide support means compared with a case in which one nozzle guide support means is provided so as to follow an entire periphery of the open flange part. 
         [0009]    According to a third aspect of the present invention, in addition to the first or second aspect, the nozzle guide support means comprises a cap that supports the nozzle guide in a radially and axially floating state, a rivet that fixes the cap to the open flange part, and a spacer that is fitted around the outer periphery of the rivet to thus form the projecting part. 
         [0010]    In accordance with the third aspect, since the nozzle guide support means includes the cap supporting the nozzle guide in a radially and axially floating state, the rivet fixing the cap to the open flange part, and the spacer fitted onto the outer periphery of the rivet to thus form a projecting part, not only is it possible to easily and reliably fix the cap to the open flange part, but it is also possible to restrict the gap between the open flange part and the cap with good precision by utilizing the spacer forming the projecting part. 
         [0011]    According to a fourth aspect of the present invention, in addition to the third aspect, the spacer is formed integrally with the open flange part. 
         [0012]    In accordance with the fourth aspect, since the spacer is formed integrally with the open flange part, not only is it possible to cut the number of components, but ease of operation when securing the cap and the spacer by means of the rivet also improves. 
         [0013]    According to a fifth aspect of the present invention, in addition to the third or fourth aspect, the cap comprises a stopper portion that can abut against an outer peripheral face of the open flange part. 
         [0014]    In accordance with the fifth aspect, since the cap includes the stopper portion, which can abut against the outer peripheral face of the open flange part, it is possible to prevent the cap from rotating around the rivet. 
         [0015]    According to a sixth aspect of the present invention, in addition to the first or second aspect, the nozzle guide support means comprises a clip that is joined by swaging to the open flange part, the clip integrally comprising a retaining portion that supports the nozzle guide in a radially and axially floating state, and the projecting part that engages with the recess portion of the nozzle guide. 
         [0016]    In accordance with the sixth aspect, since the nozzle guide support means is formed from the clip joined to the open flange part by swaging, and the clip integrally includes the retaining portion supporting the nozzle guide in a radially and axially floating state and the projecting part engaging with the recess portion of the nozzle guide, it is possible to form the nozzle guide support means from a single component, thus cutting the number of components and the number of assembly steps. 
         [0017]    Note that a spacer  19  of embodiments corresponds to the projecting part of the present invention, and a rivet  21  and a clip  23  of the embodiments correspond to the swaged member of the present invention. 
         [0018]    The above and other objects, characteristics and advantages of the present invention will be clear from detailed descriptions of the preferred embodiments which will be provided below while referring to the attached drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  to  FIG. 4  show a first embodiment of the present invention: 
           [0020]      FIG. 1  is a longitudinal sectional view of a combustor of a gas turbine engine; 
           [0021]      FIG. 2  is an enlarged view of part  2  in  FIG. 1 ; 
           [0022]      FIG. 3  is a view in the direction of arrow  3  in  FIG. 1 ; and 
           [0023]      FIG. 4  is a view in the direction of arrow  4  in  FIG. 1 . 
           [0024]      FIG. 5  and  FIG. 6  show a second embodiment of the present invention: 
           [0025]      FIG. 5  is a diagram corresponding to  FIG. 2  of the first embodiment; and 
           [0026]      FIG. 6  is a diagram corresponding to  FIG. 3  of the first embodiment. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0027]    A first embodiment of the present invention is explained below by reference to  FIG. 1  to  FIG. 4 . 
         [0028]    As shown in  FIG. 1 , a combustor  11  disposed so as to encircle an engine axis of a gas turbine engine includes an annular combustor main body part  12  and a dome part  13  blocking one end part of the combustor main body part  12 . A plurality of open flange parts  14  are disposed, at equal intervals on a circumference having the engine axis as the center, on the semicircular cross section dome part  13 , and the extremities of fuel nozzles  15  for injecting fuel into the interior of the combustor  11  via fuel supply holes  13   a  foamed in the center of the open flange parts  14  are covered with a nozzle guide  22  supported in a floating state by nozzle guide support means  16 . Furthermore, a plurality of spark plug fitting holes  12   a  are formed in an outer peripheral wall of the combustor main body part  12  at equal intervals in the circumferential direction, and the extremities of spark plugs  18  are inserted into spark plug support collars  24  supported in a floating state by spark plug support means  17  provided on the spark plug fitting holes  12   a.  The fuel nozzle  15  includes an air supply hole encircling the periphery of the fuel injection hole, and air passing through the air supply hole is supplied into the interior of the combustor  11  via the periphery of the fuel injection hole in a swirl flow. The combustor  11  is cantilever-supported on a casing of the gas turbine engine via an inner peripheral part thereof, and since base end parts of the fuel nozzles  15  and the spark plugs  18  are cantilever-supported on the casing, the fuel nozzles  15  and the spark plugs  18  move relative to the combustor  11  due to a difference in the amount of thermal expansion of each part accompanying change in temperature of the gas turbine engine. In order to allow this relative movement, the extremities of the fuel nozzles  15  are covered with the nozzle guide  22  supported on the nozzle guide support means  16  in a floating state, and the extremities of the spark plugs  18  are inserted into spark plug support collars  24  supported by the spark plug support means  17  in a floating state. Formed in the outer peripheral wall and an inner peripheral wall of the combustor main body part  12  are a plurality of air inlet holes  12   b  for introducing air for combustion into the interior of the combustor  11 . 
         [0029]    The structure of the nozzle guide support means  16  is now explained by reference to  FIG. 2  to  FIG. 4 . 
         [0030]    The open flange part  14  of the combustor  11  includes a conical portion  14   a  that enlarges in a conical manner from the outer periphery of the fuel supply hole  13   a  along an axis L of the fuel nozzle  15 , a flat portion  14   b  that extends from the extremity of the conical portion  14   a  radially outward with respect to the axis L, and two projecting portions  14   c  that project radially outward from two positions, having the axis L interposed therebetween, at the radially outer ends of the flat portion  14   b,  rivet holes  14   d  extending through extremities of the projecting portions  14   c.  A cylindrical spacer  19  and a cap  20  formed by bending a plate material are superimposed on the projecting portion  14   c  and are fixed by swaging the extremity of a rivet  21  extending in the axis L direction through a rivet hole  20   a  of the cap  20 , the spacer  19 , and the rivet hole  14   d  of the projecting portion  14   c.  Formed at the radially outer end of the cap  20  is a stopper portion  20   b  that is bent at right angles, the stopper portion  20   b  engaging with an outer peripheral face of the radially outer end of the projecting portion  14   c  of the open flange part  14 . 
         [0031]    The nozzle guide  22 , which is formed into an annular shape, includes a cylindrical portion  22   a  into which the fuel nozzle  15  is fitted and a bottom flange portion  22   c  that is bent from a corner portion  22   b  at one end of the cylindrical portion  22   a  at right angles and extends radially outward, and a plurality of cooling holes  22   d  extending in the axis L direction extend through a radially inner end part of the bottom flange portion  22   c  that is adjacent to the corner portion  22   b.  Two projecting portions  22   e  superimposed on the two projecting portions  14   c  of the open flange part  14  project from radially outer ends of the bottom flange portion  22   c  of the nozzle guide  22 , and U-shaped recess portions  22   f  opening radially outward are formed in the projecting portions  22   e.    
         [0032]    The projecting portion  22   e  of the nozzle guide  22  is sandwiched between the cap  20  and the projecting portion  14   c  of the open flange part  14 , and the recess portion  22   f  of the nozzle guide  22  is loosely fitted onto the outer periphery of the spacer  19 . In this state, the bottom flange portion  22   c  and the projecting portion  22   e  of the nozzle guide  22  have a gap a (see  FIG. 2 ) in the axis L direction between the cap  20  and the flat portion  14   b  and the projecting portion  14   c  of the open flange part  14 . The recess portion  22   f  of the nozzle guide  22  has a gap β (see  FIG. 2 ) in the radial direction and a gap γ (see  FIG. 3 ) in the circumferential direction between itself and the outer periphery of the spacer  19 . Therefore, the nozzle guide  22  can move in the axis L direction, the radial direction, and the circumferential direction relative to the open flange part  14 . 
         [0033]    The operation of the embodiment of the present invention having the above arrangement is now explained. 
         [0034]    During running of the gas turbine engine, air that has been compressed by a compressor is supplied to a space around the combustor  11  and is supplied therefrom to the interior of the combustor  11  after passing through the air inlet holes  12   b  of the combustor main body part  12  and the interior of the fuel nozzles  15 , and the air is mixed with fuel injected from the fuel nozzle  15  in the interior of the combustor  11 , thus carrying out combustion. Combustion gas generated by combustion is discharged from the combustor  11  and drives a turbine, and is then discharged via an exhaust nozzle and generates thrust. The spark plugs  18  ignite the mixed gas when the gas turbine engine is started, and combustion of the mixed gas continues automatically after starting the gas turbine engine. Furthermore, air in the space around the combustor  11  passes through the cooling holes  22   d  of the nozzle guide  22  and is supplied to the interior of the combustor  11 , and in this process it cools the open flange part  14  and the fuel nozzle  15 . 
         [0035]    Since the annular combustor  11  is cantilever-supported on the casing of the gas turbine engine via its inner peripheral part, and the base end parts of the fuel nozzles  15  and the spark plugs  18  are also cantilever-supported on the casing of the gas turbine engine, the fuel nozzles  15  and the spark plugs  18  move relative to the combustor  11  due to differences in the amount of thermal expansion accompanying change in temperature of the gas turbine engine. 
         [0036]    However, since the nozzle guide  22  of the fuel nozzle  15  is supported on the open flange part  14  of the combustor  11  via the nozzle guide support means  16 , this nozzle guide support means  16  enables the nozzle guide  22  to move relative to the open flange part  14  in the axis L direction in a range of the gap α, in the radial direction in a range of the gap β, and in the circumferential direction in a range of the gap γ, these relative movements being allowed by the action of the gaps α, β, and γ. 
         [0037]    Since assembly of the nozzle guide support means  16  is carried out by swaging the extremity of the rivet  21  extending through the rivet hole  20   a  of the cap  20 , the spacer  19 , and the rivet hole  14   d  of the projecting portion  14   c  of the open flange part  14  in the axis L direction, it becomes possible to cut the production time and the production cost compared with a case in which the nozzle guide support means  16  is assembled by welding or brazing. Furthermore, since the nozzle guide support means  16 , which are divided into two parts, are disposed on the open flange part  14  at intervals of 180° in the circumferential direction, it is possible to cut the total weight of the nozzle guide support means  16  compared with a case in which one nozzle guide support means  16  is provided so as to follow the entire periphery of the open flange part  14 . 
         [0038]    Moreover, since the nozzle guide support means  16  includes the cap  20  supporting the nozzle guide  22  in a floating state, the rivet  21  fixing the cap  20  to the open flange part  14 , and the spacer  19  fitted onto the outer periphery of the rivet  21  to thus form a projecting part for preventing rotation, it is possible to prevent rotation of the nozzle guide  22 , and not only is it possible to easily and reliably fix the cap  20  to the open flange part  14 , but it is also possible to restrict the gap in the axis L direction between the open flange part  14  and the cap  20  with good precision by utilizing the spacer  19  forming the projecting part. Furthermore, it becomes easy to replace the nozzle guide  22  with a new product when it has deteriorated, thus improving the ease of maintenance. 
         [0039]    Moreover, since the cap  20  includes the stopper portion  20   b,  which can abut against the outer peripheral face of the projecting portion  14   c  of the open flange part  14 , it is possible by means of the stopper portion  20   b  to prevent the cap  20  from rotating around the rivet  21 . 
         [0040]    A second embodiment of the present invention is now explained by reference to  FIG. 5  and  FIG. 6 . 
         [0041]    The second embodiment is different from the first embodiment in terms of the structure of nozzle guide support means  16 , the nozzle guide support means  16  being formed from a clip  23 , which is a single member. The clip  23 , which is formed by bending a substantially rectangular plate material through 180° via its middle part, is fixed to a projecting portion  14   c  of an open flange part  14  by swaging, and includes two projecting portions  23   a  and  23   b  fitted into indentations  14   e  and  14   f  formed in opposite faces of the projecting portion  14   c  of the open flange part  14 . One projecting portion  23   a  is formed into a hemispherical shape, is fixed to the indentation  14   e,  which is hemispherical, of the projecting portion  14   c  of the open flange part  14 , and is loosely fitted into a recess portion  22   f  of a projecting portion  22   e  of a nozzle guide  22 , and a retaining portion  23   c  extending radially inward from the projecting portion  23   a  opposes a bottom flange portion  22   c  and the projecting portion  22   e  of the nozzle guide  22  across a gap. The other projecting portion  23   b  is formed into a semi-cylindrical shape and is fixed to the indentation  14   f,  which is semi-cylindrical, of the projecting portion  14   c  of the open flange part  14 . Furthermore, a bent portion  23   d  at the radially outer end of the clip  23  abuts against a radially outer end face of the projecting portion  14   c  of the open flange part  14 , thus suppressing rotation of the clip  23  around the projecting portion  23   a.    
         [0042]    In accordance with the present embodiment, the same effects as those of the first embodiment can be achieved and, furthermore, since the nozzle guide support means  16  is formed from the clip  23 , which is a single member, joined by swaging to the open flange part  14 , it is possible to cut the number of components and the number of assembly steps compared with the nozzle guide support means  16  of the first embodiment. 
         [0043]    Embodiments of the present invention are explained above, but the present invention may be modified in a variety of ways as long as the modifications do not depart from the gist thereof. 
         [0044]    For example, in the embodiment, the spacer  19  is formed from an independent component, but this spacer  19  may be formed integrally with the open flange part  14 , and by so doing not only can the number of components be cut, but the ease of operation when securing the cap  20  and the spacer  19  by means of the rivet  21  also improves.