Abstract:
A brush seal assembly is formed of a bristle array receiving at least one housing member. Alignment structures are formed on the housing and bristle assembly to ensure that the bristle assembly will be properly positioned in a working environment.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This application relates to a brush seal, such as is used in turbine engines, wherein an assembly aid ensures seal bristles are properly positioned when assembled to a housing. 
         [0002]    Brush seals are utilized to block the flow of gases or other fluids in many applications. One common application is in a turbine engine. As known, a turbine engine, such as a gas turbine engine, includes a compressor for compressing air and delivering it downstream into a combustion section. The air is mixed with fuel in the combustion section and burned. Products of this combustion then pass over turbine rotors, which are driven to rotate. 
         [0003]    Several locations along this assembly require sealing to direct the various fluid flows in proper directions. One known seal type is a brush seal. In a known brush seal, a bristle array is mounted between an upstream housing and a downstream housing. The housings provide some structural rigidity to the bristles and also mount the seal assembly in a housing. The bristles in the array have a proper orientation relative to a flow direction, in that the bristles extend at an angle which is common with a direction of rotation of a part against which the brush seal seals. Thus, there is a desired orientation for the bristle array, and a desired side of the bristle array which is to receive the upstream housing and a side which receives the downstream housing. Unfortunately, in the prior art, the housings have sometimes been mounted to the improper side of the bristle array. When this occurs, the bristle array may be improperly mounted, causing a shorter life and a less effective seal than would be desirable. 
       SUMMARY OF THE INVENTION 
       [0004]    In the disclosed embodiment of this invention, a bristle array and at least one housing have corresponding structure such that the bristle array is mounted to the housing in the correct orientation. In this manner, it is most unlikely that the bristle array would be improperly mounted to its housing. Thus, it is properly mounted when placed in the field. In one embodiment, there is an upstream housing and a downstream housing, and one of these housings has a recess for receiving an alignment member attached to the bristle array. 
         [0005]    These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a schematic view of a gas turbine engine. 
           [0007]      FIG. 2  shows a prior art seal. 
           [0008]      FIG. 3A  is a perspective view of a portion of an inventive seal. 
           [0009]      FIG. 3B  shows a first embodiment. 
           [0010]      FIG. 3C  shows a second embodiment. 
           [0011]      FIG. 3D  shows a third embodiment. 
           [0012]      FIG. 3E  shows a fourth embodiment. 
           [0013]      FIG. 4  shows the first embodiment of the present invention mounted in an operative environment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0014]    A gas turbine engine  10 , such as a turbofan gas turbine engine, circumferentially disposed about an engine centerline, or axial centerline axis  12  is shown in  FIG. 1 . The engine  10  includes a fan  14 , a compressor  16 , a combustion section  18  and a turbine  20 . As is well known in the art, air compressed in the compressor  16  is mixed with fuel which is burned in the combustion section  18  and expanded in turbine  20 . The turbine  20  includes rotors  22  which rotate in response to the expansion, driving the compressor  16  and fan  14 . The turbine  20  comprises alternating rows of rotary airfoils or blades  24  and static airfoils or vanes  26 . This structure is shown somewhat schematically in  FIG. 1 . While a particular turbine engine is shown, it should be understood that this invention extends to all turbines for any application. 
         [0015]    At several locations along the gas turbine as shown in  FIG. 1 , brush seals such as shown at  50  in  FIG. 2  may be utilized. As shown, the brush seal  50  seals against a rotating shaft  52 . The seal can seal against other rotating components, such as a rotor. Further, the seal can also seal between two fixed components. The locations for using such seals are generally as known. A bristle array  54  is sandwiched between an upstream housing  56  and a downstream housing  58  to provide rigidity to the bristle array. A weld bead  60  secures the bristles together into the array. The bristle array is then secured to the upstream housing  56  and downstream housing  58 , and the entire brush seal  50  may then be mounted within the gas turbine engine such as at housing  100 . The mounting to housing  100  is shown schematically and forms no part of this invention. 
         [0016]    As can be appreciated from  FIG. 3A , the bristle array  54  has bristles which extend along a direction which is in the same direction as the direction of the rotation of the port  52  which is to mount the brush seal. That is, the bristles extend inwardly at an angle that is not perpendicular to axis  12 . Thus, there is a desired orientation or upstream end and downstream end for the bristle array such as shown in  FIG. 2 . In the past, it is sometimes been the case that the upstream housing  56  has been mounted to the wrong face of the bristle array  54  as has been the downstream housing  58 . When this occurs the brush assembly  50  will then be mounted facing in the wrong direction within the gas turbine engine, or other application. As mentioned above, this is undesirable. 
         [0017]    Returning to  FIG. 3A , an inventive bristle array  62  is illustrated. As shown, the typical weld bead  64  secures the bristles into the bristle array  54 . However, an alignment feature  66  is also added. As shown in  FIG. 3B , the alignment feature  66  may be generally circular. As shown in  FIG. 3C , the bristle array  64  may have an alignment feature  70  which is generally rectangular. As shown in  FIG. 3D , the bristle array  172  may have an alignment feature  74  which is generally triangular. As shown in  FIG. 3E , the bristle array  76  may have an alignment feature  78  which is generally a trapezoid. Many other shapes can be utilized. The alignment feature can be formed of a material similar to bead  64 . 
         [0018]    As shown in  FIG. 4 , when assembling the brush assembly  80  including the inventive bristle array  62 , the alignment structure  66  is received in a recess  70  in a housing  68 . Of course, the recess could be formed in the other housing  72 . In addition, the recess could be formed in the weld bead  64 , with the alignment structure formed in one of the housings  68 . All that is required there be some corresponding structure in the bristle array and at least one of the housings that ensures the housing will be assembled to the proper face of the bristle array  62 . 
         [0019]    In the disclosed embodiment, the alignment feature  66 , and hence the recess  70 , extend across the entire circumference of the brush assembly. However, as can be appreciated, circumferentially spaced partial alignment features may be sufficient. 
         [0020]    Although an 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.