Circumferential Seal with Ceramic Runner

Abstract

The disclosure describes a circumferential seal applicable to turbine engines. The circumferential seal includes a ceramic runner, an annular seal ring, at least one tolerance ring, and a pair of sealing rings. The runner is circumscribed about a shaft or a carrier within a recess along the shaft and is bounded by a shoulder and a clamping ring. At least one non-sealing spring mechanism is disposed between and directly contacts the shoulder and the first end of the runner. A second end of the runner directly contacts the clamping ring. In other embodiments, at least one non-sealing spring mechanism is disposed between and directly contacts the second end and the clamping ring and the first end directly contacts the shoulder. An anti-rotation element is attached to the clamping ring, carrier, or shaft and extends into a slot or hole or slot along the runner. The spring(s) applies a biasing force onto the runner toward the clamping ring or shoulder. The annular seal ring is rotationally stationary and circumscribed about the runner. The tolerance ring(s) directly contacts the runner and the shaft. The runner is fixed to the shaft or carrier via the tolerance ring(s), anti-rotation element, and spring(s) so that the runner rotates with the shaft. The sealing rings directly contact the runner and the shaft along the annular gap about the tolerance ring(s).

What is claimed is: 
     
         1 . A circumferential seal comprising:
 (a) a ceramic runner circumscribed about a recess along a shaft, said recess bounded by a shoulder and a clamping ring, a first annular gap disposed between a first end of said ceramic runner and said shoulder, a second end of said ceramic runner directly contacts said clamping ring, an anti-rotation pin attached to said clamping ring and extends into a slot along said ceramic runner, at least one non-sealing spring mechanism disposed between and directly contacts said shoulder and said first end along said first annular gap, said at least one non-sealing spring mechanism applies a biasing force onto said ceramic runner toward said clamping ring;   (b) an annular seal ring circumscribed about said ceramic runner and disposed within a seal housing so that said annular seal ring is rotationally stationary;   (c) at least one tolerance ring directly contacts said ceramic runner and said shaft along a second annular gap between said ceramic runner and said shaft, said ceramic runner fixed to said shaft via said at least one tolerance ring, said anti-rotation pin, and said at least one non-sealing spring mechanism so that said ceramic runner rotates with said shaft, said at least one non-sealing spring mechanism expands and contracts in response to expansion and contraction of said ceramic runner; and   (d) a pair of sealing rings directly contacts said ceramic runner and said shaft between said pair of sealing rings.   
     
     
         2 . The circumferential seal of  claim 1 , wherein said at least one non-sealing spring mechanism is a wave spring. 
     
     
         3 . The circumferential seal of  claim 1 , wherein said at least one non-sealing spring mechanism is a compression spring. 
     
     
         4 . The circumferential seal of  claim 1 , wherein said at least one non-sealing spring mechanism is a plurality of compression springs separately disposed about said first annular gap, each said compression spring separately attached to said shoulder. 
     
     
         5 . The circumferential seal of  claim 1 , wherein each said tolerance ring and each said sealing ring separately disposed within an equal number of annular grooves along said ceramic runner. 
     
     
         6 . The circumferential seal of  claim 1 , wherein each said tolerance ring and each said sealing ring separately disposed within an equal number of annular grooves along said shaft. 
     
     
         7 . The circumferential seal of  claim 1 , wherein said annular seal ring forms a contact seal about said ceramic runner. 
     
     
         8 . The circumferential seal of  claim 1 , wherein said annular seal ring forms a non-contact seal about said ceramic runner. 
     
     
         9 . The circumferential seal of  claim 1 , wherein at least one said sealing ring is an O-ring, a spring-energized seal, or a high-temperature metallic seal ring. 
     
     
         10 . A circumferential seal comprising:
 (a) a ceramic runner circumscribed about a recess along a shaft, said recess bounded by a shoulder and a clamping ring, a first annular gap disposed between a second end of said ceramic runner and said clamping ring, a first end of said ceramic runner directly contacts said shoulder along said shaft, an anti-rotation pin attached to said shoulder and extends into a slot along said ceramic runner, at least one non-sealing spring mechanism disposed between and directly contacts said clamping ring and said second end along said first annular gap, said at least one non-sealing spring mechanism applies a biasing force onto said ceramic runner toward said shoulder;   (b) an annular seal ring circumscribed about said ceramic runner and disposed within a seal housing so that said annular seal ring is rotationally stationary;   (c) at least one tolerance ring directly contacts said ceramic runner and said shaft along a second annular gap between said ceramic runner and said shaft, said ceramic runner fixed to said shaft via said at least one tolerance ring, said anti-rotation pin, and said at least one non-sealing spring mechanism so that said ceramic runner rotates with said shaft, said at least one non-sealing spring mechanism expands and contracts in response to expansion and contraction of said ceramic runner; and   (d) a pair of sealing rings directly contacts said ceramic runner and said shaft along said second annular gap, said at least one tolerance ring disposed between said pair of sealing rings.   
     
     
         11 . The circumferential seal of  claim 10 , wherein said at least one non-sealing spring mechanism is a wave spring. 
     
     
         12 . The circumferential seal of  claim 10 , wherein said at least one non-sealing spring mechanism is a compression spring. 
     
     
         13 . The circumferential seal of  claim 10 , wherein said at least one non-sealing spring mechanism is a plurality of compression springs separately disposed about said first annular gap, each said compression spring separately attached to said clamping ring. 
     
     
         14 . The circumferential seal of  claim 10 , wherein each said tolerance ring and each said sealing ring separately disposed within an equal number of annular grooves along said ceramic runner. 
     
     
         15 . The circumferential seal of  claim 10 , wherein each said tolerance ring and each said sealing ring separately disposed within an equal number of annular grooves along said shaft. 
     
     
         16 . The circumferential seal of  claim 10 , wherein said annular seal ring forms a contact seal about said ceramic runner. 
     
     
         17 . The circumferential seal of  claim 10 , wherein said annular seal ring forms a non-contact seal about said ceramic runner. 
     
     
         18 . The circumferential seal of  claim 10 , wherein at least one said sealing ring is an O-ring, a spring-energized seal, or a high-temperature metallic seal ring. 
     
     
         19 . A circumferential seal comprising:
 (a) a carrier disposed about and directly contacts a shaft within a recess along said shaft, said carrier rotatable with said shaft, said carrier having a shoulder at one end;   (b) a ceramic runner circumscribed about said carrier, said ceramic runner disposed between said shoulder and a clamping ring, a first annular gap disposed between a first end of said ceramic runner and said shoulder, a second end of said ceramic runner directly contacts said clamping ring, an anti-rotation key attached to said clamping ring and extends into a slot along said ceramic runner, at least one non-sealing spring mechanism directly contacts said shoulder and said first end along said first annular gap, said at least one non-sealing spring mechanism applies a biasing force onto said ceramic runner toward said clamping ring;   (c) an annular seal ring circumscribed about said ceramic runner and disposed within a seal housing so that said annular seal ring is rotationally stationary;   (d) at least one tolerance ring directly contacts said ceramic runner and said carrier along a second annular gap between said ceramic runner and said carrier, said ceramic runner fixed to said carrier via said at least one tolerance ring, said anti-rotation key, and said at least one non-sealing spring mechanism so that said ceramic runner rotates with said carrier, said at least one non-sealing spring mechanism expands and contracts in response to expansion and contraction of said ceramic runner; and   (e) a pair of sealing rings directly contacts said ceramic runner and said carrier along said second annular gap, said at least one tolerance ring disposed between said pair of sealing rings.   
     
     
         20 . The circumferential seal of  claim 19 , wherein said at least one non-sealing spring mechanism is a wave spring. 
     
     
         21 . The circumferential seal of  claim 19 , wherein said at least one non-sealing spring mechanism is a compression spring. 
     
     
         22 . The circumferential seal of  claim 19 , wherein said at least one non-sealing spring mechanism is a plurality of compression springs separately disposed about said first annular gap, each said compression spring separately attached to said shoulder. 
     
     
         23 . The circumferential seal of  claim 19 , wherein each said tolerance ring and each said sealing ring separately disposed within an equal number of annular grooves along said carrier. 
     
     
         24 . The circumferential seal of  claim 19 , wherein each said tolerance ring and each said sealing ring separately disposed within an equal number of annular grooves along said ceramic runner. 
     
     
         25 . The circumferential seal of  claim 19 , wherein said annular seal ring forms a contact seal about said ceramic runner. 
     
     
         26 . The circumferential seal of  claim 19 , wherein said annular seal ring forms a non-contact seal about said ceramic runner. 
     
     
         27 . The circumferential seal of  claim 19 , wherein at least one said sealing ring is an O-ring, a spring-energized seal, or a high-temperature metallic seal ring. 
     
     
         28 . A circumferential seal comprising:
 (a) a carrier disposed about and directly contacts a shaft within a recess along said shaft, said carrier rotatable with said shaft, said carrier having a shoulder at one end;   (b) a ceramic runner circumscribed about said carrier, said ceramic runner disposed between said shoulder and a clamping ring, a first annular gap disposed between a second end of said ceramic runner and said clamping ring, a first end of said ceramic runner directly contacts said shoulder, an anti-rotation key attached to said shoulder and extends into a slot along said ceramic runner, at least one non-sealing spring mechanism directly contacts said clamping ring and said second end along said first annular gap, said at least one non-sealing spring mechanism applies a biasing force onto said ceramic runner toward said shoulder;   (c) an annular seal ring circumscribed about said ceramic runner and disposed within a seal housing so that said annular seal ring is rotationally stationary;   (d) at least one tolerance ring directly contacts said ceramic runner and said carrier along a second annular gap between said ceramic runner and said carrier, said ceramic runner fixed to said carrier via said at least one tolerance ring, said anti-rotation key, and said at least one non-sealing spring mechanism so that said ceramic runner rotates with said carrier, said at least one non-sealing spring mechanism expands and contracts in response to expansion and contraction of said ceramic runner; and   (e) a pair of sealing rings directly contacts said ceramic runner and said carrier along said second annular gap, said at least one tolerance ring disposed between said pair of sealing rings.   
     
     
         29 . The circumferential seal of  claim 28 , wherein said at least one non-sealing spring mechanism is a wave spring. 
     
     
         30 . The circumferential seal of  claim 28 , wherein said at least one non-sealing spring mechanism is a compression spring. 
     
     
         31 . The circumferential seal of  claim 28 , wherein said at least one non-sealing spring mechanism is a plurality of compression springs separately disposed about said first annular gap, each said compression spring separately attached to said clamping ring. 
     
     
         32 . The circumferential seal of  claim 28 , wherein each said tolerance ring and each said sealing ring separately disposed within an equal number of annular grooves along said carrier. 
     
     
         33 . The circumferential seal of  claim 28 , wherein each said tolerance ring and each said sealing ring separately disposed within an equal number of annular grooves along said ceramic runner. 
     
     
         34 . The circumferential seal of  claim 28 , wherein said annular seal ring forms a contact seal about said ceramic runner. 
     
     
         35 . The circumferential seal of  claim 28 , wherein said annular seal ring forms a non-contact seal about said ceramic runner. 
     
     
         36 . The circumferential seal of  claim 28 , wherein at least one said sealing ring is an O-ring, a spring-energized seal, or a high-temperature metallic seal ring. 
     
     
         37 . A circumferential seal comprising:
 (a) a carrier disposed about and directly contacts a shaft within a recess along said shaft, said carrier rotatable with said shaft, said carrier having a shoulder at one end;   (b) a ceramic runner circumscribed about said carrier, said ceramic runner disposed between said shoulder and a clamping ring, a first annular gap disposed between a first end of said ceramic runner and said shoulder, a second end of said ceramic runner directly contacts said clamping ring, an anti-rotation screw attached to said carrier and extends into a hole along said ceramic runner, at least one non-sealing spring mechanism directly contacts said shoulder and said first end along said first annular gap, said at least one non-sealing spring mechanism applies a biasing force onto said ceramic runner toward said clamping ring;   (c) an annular seal ring circumscribed about said ceramic runner and disposed within a seal housing so that said annular seal ring is rotationally stationary;   (d) at least one tolerance ring directly contacts said ceramic runner and said carrier along a second annular gap between said ceramic runner and said carrier, said ceramic runner fixed to said carrier via said at least one tolerance ring, said anti-rotation screw, and said at least one non-sealing spring mechanism so that said ceramic runner is rotatable with said carrier, said at least one non-sealing spring mechanism expands and contracts in response to expansion and contraction of said ceramic runner; and   (e) a pair of sealing rings, at least one said sealing ring directly contacts said ceramic runner and said carrier along said second annular gap, said at least one tolerance ring and said anti-rotation screw disposed between said pair of sealing rings.   
     
     
         38 . The circumferential seal of  claim 37 , wherein said at least one non-sealing spring mechanism is a wave spring. 
     
     
         39 . The circumferential seal of  claim 37 , wherein said at least one non-sealing spring mechanism is a compression spring. 
     
     
         40 . The circumferential seal of  claim 37 , wherein said at least one non-sealing spring mechanism is a plurality of compression springs separately disposed about said first annular gap, each said compression spring separately attached to said shoulder. 
     
     
         41 . The circumferential seal of  claim 37 , wherein each said tolerance ring and one said sealing ring separately disposed within an equal number of annular grooves along said carrier and another said sealing ring disposed within another said annular groove along said clamping ring. 
     
     
         42 . The circumferential seal of  claim 37 , wherein each said tolerance ring and one said sealing ring separately disposed within an equal number of annular grooves along said ceramic runner and another said sealing ring disposed within another said annular groove along said clamping ring. 
     
     
         43 . The circumferential seal of  claim 37 , wherein said annular seal ring forms a contact seal about said ceramic runner. 
     
     
         44 . The circumferential seal of  claim 37 , wherein said annular seal ring forms a non-contact seal about said ceramic runner. 
     
     
         45 . The circumferential seal of  claim 37 , wherein at least one said sealing ring is an O-ring, a spring-energized seal, or a high-temperature metallic seal ring. 
     
     
         46 . A circumferential seal comprising:
 (a) a carrier disposed about and directly contacts a shaft within a recess along said shaft, said carrier rotatable with said shaft, said carrier having a shoulder at one end;   (b) a ceramic runner circumscribed about said carrier, said ceramic runner disposed between said shoulder and a clamping ring, a first annular gap disposed between a second end of said ceramic runner and said clamping ring, a first end of said ceramic runner directly contacts said shoulder, an anti-rotation screw attached to said carrier and extends into a hole along said ceramic runner, at least one non-sealing spring mechanism directly contacts said clamping ring and said second end along said first annular gap, said at least one non-sealing spring mechanism applies a biasing force onto said ceramic runner toward said shoulder;   (c) an annular seal ring circumscribed about said ceramic runner and disposed within a seal housing so that said annular seal ring is rotationally stationary;   (d) at least one tolerance ring directly contacts said ceramic runner and said carrier along a second annular gap between said ceramic runner and said carrier, said ceramic runner fixed to said carrier via said at least one tolerance ring, said anti-rotation screw, and said at least one non-sealing spring mechanism so that said ceramic runner is rotatable with said carrier, said at least one non-sealing spring mechanism expands and contracts in response to expansion and contraction of said ceramic runner; and   (e) a pair of sealing rings, at least on said sealing ring directly contacts said ceramic runner and said carrier along said second annular gap, said at least one tolerance ring and said anti-rotation screw disposed between said pair of sealing rings.   
     
     
         47 . The circumferential seal of  claim 46 , wherein said at least one non-sealing spring mechanism is a wave spring. 
     
     
         48 . The circumferential seal of  claim 46 , wherein said at least one non-sealing spring mechanism is a compression spring. 
     
     
         49 . The circumferential seal of  claim 46 , wherein said at least one non-sealing spring mechanism is a plurality of compression springs separately disposed about said first annular gap, each said compression spring separately attached to said clamping ring. 
     
     
         50 . The circumferential seal of  claim 46 , wherein each said tolerance ring and one said sealing ring separately disposed within an equal number of annular grooves along said carrier and another said sealing ring disposed within another said annular groove along said clamping ring. 
     
     
         51 . The circumferential seal of  claim 46 , wherein each said tolerance ring and one said sealing ring separately disposed within an equal number of annular grooves along said ceramic runner and another said sealing ring disposed within another said annular groove along said clamping ring. 
     
     
         52 . The circumferential seal of  claim 46 , wherein said annular seal ring forms a contact seal about said ceramic runner. 
     
     
         53 . The circumferential seal of  claim 46 , wherein said annular seal ring forms a non-contact seal about said ceramic runner. 
     
     
         54 . The circumferential seal of  claim 46 , wherein at least one said sealing ring is an O-ring, a spring-energized seal, or a high-temperature metallic seal ring.