Top hat bearing retainer for variable vane actuator

Abstract

A variable vane actuation system with a plurality of vanes which may be rotated to change an approach angle of associated airfoils. A cylinder drives a piston rod to in turn cause a linkage system to vary the approach angle of the airfoils. The cylinder has a tailstock at an end remote from the piston rod. A spherical bearing mounts the tailstock. A bearing retainer provides a stop to prevent undue rotation of the tailstock relative to the bearing. A compressor and a gas turbine engine are also disclosed.

1 . A variable vane actuator comprising:
 a plurality of vanes which may be rotated to change an approach angle of associated airfoils;   a cylinder mounted to drive a piston rod to in turn cause a linkage system to vary the approach angle of said airfoils, said cylinder having a tailstock at an end remote from the piston rod, with said tailstock being pivotably mounted within a clevis, and on a bolt;   a spherical bearing between said bolt and said tailstock, with said spherical bearing including an inner member riding on said bolt and having a spherical outer surface, and an outer member which moves with said tailstock, and has an spherical inner surface moveable on said spherical outer surface of said inner member;   said clevis including two spaced ledges; and   a bearing retainer between one of said ledges and said spherical bearing, said bearing retainer being formed of a material that is softer than a material forming said tailstock such that said bearing retainer provides a stop to prevent undue rotation of said tailstock and said outer member relative to said inner member.   
     
     
         2 . The variable vane actuator as set forth in  claim 1 , wherein said bearing retainer has a shape of a top hat, with an extension extending from a planer section, said planer section abutting said spherical bearing, and said extension fitting within an opening in said one of said ledges, with said bolt extending through said extension, through said planer portion, through said inner member, and then through a second of said ledges. 
     
     
         3 . The variable vane actuator as set forth in  claim 1 , wherein said bearing retainer is generally cylindrical. 
     
     
         4 . The variable vane actuator as set forth in  claim 3 , wherein said bearing retainer has a truncated portion associated with a limited circumferential extent of said bearing retainer, with said truncated portion being positioned adjacent an under surface of said cylinder from which said tailstock extends. 
     
     
         5 . The variable vane actuator as set forth in  claim 1 , wherein said bearing retainer is formed of one of a composite or metal. 
     
     
         6 . The variable vane actuator as set forth in  claim 1 , wherein a first gap is defined between said bearing retainer and said tailstock, and a second gap is defined between a second of said ledges and said tailstock, and said first gap being smaller than said second gap. 
     
     
         7 . The variable vane actuator as set forth in  claim 1 , wherein said one of said ledges receives a head of said bolt. 
     
     
         8 . A compressor section comprising:
 a plurality of compressor stages spaced for rotation about a central axis;   a plurality of vanes positioned between adjacent ones of said plurality of compressor stages, with said plurality of vanes being provided with an airfoil for directing air to a downstream compressor stage, and an approach angle of said plurality of airfoils being changeable by an actuator;   the actuator including a cylinder mounted to drive a piston rod to in turn cause a linkage system to vary the approach angle of said airfoils, said cylinder having a tailstock at an end remote from the piston rod, with said tailstock being pivotably mounted within a clevis, and on a bolt;   a spherical bearing between said bolt and said tailstock, with said spherical bearing including an inner member riding on said bolt and having a spherical outer surface, and an outer bearing member which moves with said tailstock, and has a spherical inner surface moveable on said spherical outer surface of said inner member;   said clevis including two spaced ledges; and   a bearing retainer between one of said ledges and said spherical bearing and said tailstock, said bearing retainer being formed of a material that is softer than a material forming said tailstock such that said bearing retainer provides a stop to prevent undue rotation of said tailstock and said outer member relative to said inner member.   
     
     
         9 . The compressor as set forth in  claim 8 , wherein said bearing retainer has a shape of a top hat, with an extension extending from a planer section, said planer section abutting said spherical bearing, and said extension fitting within an opening in said one of said ledges, with said bolt extending through said extension, through said planer portion, through said inner member, and then through a second of said ledges. 
     
     
         10 . The compressor as set forth in  claim 8 , wherein said bearing retainer is generally cylindrical. 
     
     
         11 . The compressor as set forth in  claim 10 , wherein said bearing retainer has a truncated portion associated with a limited circumferential extent of said bearing retainer, with said truncated portion being positioned adjacent an under surface of said cylinder from which said tailstock extends. 
     
     
         12 . The compressor as set forth in  claim 8 , wherein said bearing retainer is formed of one of a composite or metal. 
     
     
         13 . The compressor as set forth in  claim 8 , wherein a first gap is defined between said bearing retainer and said tailstock, and a second gap is defined between a second of said ledges and said tailstock, and said first gap being smaller than said second gap. 
     
     
         14 . The compressor as set forth in  claim 8 , wherein said one of said ledges receives a head of said bolt. 
     
     
         15 . A gas turbine engine comprising:
 a compressor section, a combustor, and a turbine section;   said compressor section including a plurality of compressor stages spaced for rotation about a central axis;   a plurality of vanes positioned between adjacent ones of said plurality of compressor stages, with said plurality of vanes being provided with an airfoil for directing air to a downstream compressor stage, and an approach angle of said plurality of airfoils being changeable by an actuator;   the actuator including a cylinder mounted to drive a piston rod to in turn cause an actuator to vary the approach angle of said airfoils, said cylinder having a tailstock at an end remote from the piston rod, with said tailstock being pivotably mounted within a clevis, and on a bolt;   a spherical bearing between said bolt and said tailstock, with said spherical bearing including an inner member riding on said bolt and having a spherical outer surface, and an outer bearing member which moves with said tailstock, and has a spherical inner surface moveable on said spherical outer surface of said inner member;   said clevis including two spaced ledges; and   a bearing retainer between one of said ledges and said spherical bearing and said tailstock, said bearing retainer being formed of a material that is softer than a material forming said tailstock such that said bearing retainer provides a stop to prevent undue rotation of said tailstock and said outer member relative to said inner member and said bolt.   
     
     
         16 . The engine as set forth in  claim 15 , wherein said bearing retainer has a shape of a top hat, with an extension extending from a planer section, said planer section abutting said spherical bearing, and said extension fitting within an opening in said one of said ledges, with said bolt extending through said extension through said planer portion, through said inner member, and then through a second of said ledges. 
     
     
         17 . The engine actuator as set forth in  claim 15 , wherein said bearing retainer is generally cylindrical. 
     
     
         18 . The engine as set forth in  claim 17 , wherein said bearing retainer has a truncated portion associated with a limited circumferential extent of said bearing retainer, with said truncated portion being positioned adjacent an under surface of said cylinder from which said tailstock extends. 
     
     
         19 . The engine as set forth in  claim 15 , wherein a first gap is defined between said bearing retainer and said tailstock, and a second gap is defined between a second of said ledges and said tailstock, and said first gap being smaller than said second gap. 
     
     
         20 . The engine as set forth in  claim 15 , wherein said one of said ledges receives a head of said bolt.