Sealing apparatus and method and machinery utilizing same

Claim 2

Structure having a housing defining an opening, a relatively rotatable shaft means received in said opening, and a seal apparatus circumscribing said shaft means and cooperating with said housing and said shaft means to substantially prevent leakage of a liquid through said opening in response to a flow of pressurized sealing fluid to said seal apparatus, and centrifugally responsive valve means upstream of said seal apparatus and rotating to control said sealing fluid flow as a function of rotational speed.

Claim 3

The invention of claim 1 wherein said shaft means is rotatable and defines flow path means for conducting said flow of sealing fluid to said seal apparatus, said centrifugally responsive valve means being carried by said shaft means for rotation therewith.

Claim 4

The invention of claim 2 wherein said shaft means defines a chamber therein, said chamber defining a portion of said flow path means, said valve means including a centrifugally responsive valve element disposed in said chamber, said valve element shifting between a first position and a second position in response to centrifugal force to control said flow of sealing fluid.

Claim 5

The invention of claim 3 wherein said chamber is annular, said valve element extending circumferentially within said annular chamber.

Claim 6

The invention of claim 4 wherein said valve element comprises an elongate strip of resilient shape-retaining material, said valve element strip including a portion thereof which is spaced radially inwardly of a radially outer wall of said chamber in said first position of said valve element, said portion moving radially outwardly in response to centrifugal force to engage said wall in said second position of said valve element.

Claim 7

The invention of claim 5 wherein said wall defines a passage leading to said seal apparatus and defining a part of said flow path means, said passage opening to said chamber on said radially outer wall, said valve element portion spanning said passage opening in said second position of said valve element to control said flow of sealing fluid.

Claim 8

The invention of claim 6 wherein said valve element portion defines a flow restricting metering orifice aligning with said passage in second position of said valve element.

Claim 9

The invention of claim 6 wherein said valve element strip portion defines a radius which is greater than the radius defined by said radially outer wall of said annular chamber, said elongate valve element strip defining a pair of opposite end sections engaging said radially outer wall, one of said end sections slidably engaging said wall.

Claim 10

The invention of claim 6 wherein said valve element elongate strip defines a pair of opposite end sections, said valve element strip being secured to said shaft means adjacent one of said pair of end sections.

Claim 11

The invention of claim 9 wherein said pair of end sections are secured to said radially outer wall, said valve element strip including a pair of serpentine-shaped elastic sections, one of said pair of serpentine-shaped elastic sections being interposed between each one of said pair of end sections and said portion to allow relative motion therebetween in response to centrifugal force.

Claim 12

The invention of claim 9 wherein said valve element strip in said first position defines a spiral shape within said annular chamber.

Claim 13

The invention of claim 11 wherein said one end section extends readially inwardly from said radially outer wall of said annular chamber to define an abutment engageable by the other of said pair of end sections.

Claim 14

The invention of claim 12 wherein said valve element strip is substantially U-shaped in transverse cross section.

Claim 15

The invention of claim 1 wherein said housing includes an axially and circumferentially extending wall substantially defining said opening, said housing wall being spaced radially outwardly of the radially outer surface of said shaft means to define an axially extending clearance therebetween, said seal apparatus including at least two circumferentially extending and axially spaced apart knife-edge seal elements extending radially between said housing wall and shaft means for cooperating therewith to substantially define an annular chamber circumscribing said shaft means.

Claim 16

A turbo machine comprising: a housing defining a bore; a rotatable shaft means received in said bore; a compressor wheel mounted on said shaft means for rotation therewith, said compressor wheel discharging pressurized air to a discharge area; a sealing structure circumscribing said shaft means and cooperating with said shaft means and said housing to resist leakage therepast of a liquid in response to a flow of pressurized air into a chamber of said sealing structure; flow path means within said shaft means communicating said compressor discharge area with said chamber of said sealing structure for supplying said flow of pressurized air to the latter; and centrifugally responsive valve means carried by said shaft means for controlling said flow of pressurized air as a function of shaft means rotational speed.

Claim 17

A turbo machine comprising: a housing defining a bore; a rotatable shaft means received in said bore; a compressor wheel mounted on said shaft means for rotation therewith, said compressor wheel discharging pressurized air to a discharge area; a sealing structure circumscribing said shaft means and cooperating with said shaft means and said housing to resist leakage therepast of a liquid in response to a flow of pressurized air into a chamber of said sealing structure; flow path means within said shaft means communicating said compressor discharge area with said chamber of said sealing structure for supplying said flow of pressurized air to the latter; and centrifugally responsive valve means carried by said shaft means for controlling said flow of pressurized air as a function of shaft means rotational speed.

Claim 18

A turbo machine comprising: a housing defining a bore; a rotatable shaft means received in said bore; a compressor wheel mounted on said shaft means for rotation therewith, said compressor wheel discharging pressurized air to a discharge area; a sealing structure circumscribing said shaft means and cooperating with said shaft means and said housing to resist leakage therepast of a liquid in response to a flow of pressurized air into a chamber of said sealing structure; flow path means within said shaft means communicating said compressor discharge area with said chamber of said sealing structure for supplying said flow of pressurized air to the latter; and centrifugally responsive valve means carried by said shaft means for controlling said flow of pressurized air as a function of shaft means rotational speed; wherein said compressor wheel defines a back face communicating with said discharge area, said turbo machine further including a turbine wheel mounted on said shaft means for rotation therewith, said compressor wheel and said turbine wheel being axially spaced apart in back-to-back relation to define a radially extending axial space therebetween, said housing including a partition member extending radially inwardly toward said shaft means within said space, said partition member defining an opening circumscribing said shaft means and cooperating with said back face to define a clearance space, a seal apparatus cooperating with said partition member and with said shaft means to substantially prevent fluid flow therebetween, said flow path means including a fluid flow passage opening to said clearance space and communicating said discharge area with said chamber of said sealing structure.

Claim 19

A turbo machine comprising: a housing defining a bore; a rotatable shaft means received in said bore; a compressor wheel mounted on said shaft means for rotation therewith, said compressor wheel discharging pressurized air to a discharge area; a sealing structure circumscribing said shaft means and cooperating with said shaft means and said housing to resist leakage therepast of a liquid in response to a flow of pressurized air into a chamber of said sealing structure; flow path means within said shaft means communicating said compressor discharge area with said chamber of said sealing structure for supplying said flow of pressurized air to the latter; and centrifugally responsive valve means carried by said shaft means for controlling said flow of pressurized air as a function of shaft means rotational speed; wherein said compressor wheel defines a back face communicating with said discharge area, said turbo machine further including a turbine wheel mounted on said shaft means for rotation therewith, said compressor wheel and said turbine wheel being axially spaced apart in back-to-back relation to define a radially extending axial space therebetween, said housing including a partition member extending radially inwardly toward said shaft means within said space, said partition member defining an opening circumscribing said shaft means and cooperating with said back face to define a clearance space, a seal apparatus cooperating with said partition member and with said shaft means to substantially prevent fluid flow therebetween, said flow path means including a fluid flow passage opening to said clearance space and communicating said discharge area with said chamber of said sealing structure.

Claim 20

The invention of claim 16 wherein each of said compressor wheel and said turbine wheel define a shoulder confronting the respective shoulder of the other, said seal apparatus being annular and disposed upon the shoulders of said compressor wheel and turbine wheel, said seal apparatus defining a radially extending notch communicationg therethrough and opening to said clearance space, said notch defining said fluid flow passage.

Claim 21

The invention of claim 16 wherein said shaft means defines a cavity therein, the centrifugally responsive valve means being received in said cavity.

Claim 22

The invention of claim 18 wherein said cavity is annular and includes a radially outer wall, said shaft means defining a passage opening on said radially outer wall and communicating with said chamber of said sealing structure, said valve means moving between a first position spaced from said radially outer wall and a second position engaging said radially outer wall adjacent said passage opening in response to centrifugal force.

Claim 23

The invention of claim 19 wherein said valve means includes an elongate strip of resilient shape-retaining material extending circumferentially within said annular cavity.

Claim 24

The invention of claim 20 wherein said elongate strip defines a pair of opposite ends and in said first position a spiral shape within said annular cavity, said elongate strip being secured to said radially outer wall adjacent one of said pair of opposite ends, the other of said pair of opposite ends moving into and out of engagement with said radially outer wall in response to centrifugal force to move said valve means respectively between said first and said second positions.

Claim 25

The invention of claim 21 wherein said elongate strip is U-shaped in transverse cross section.

Claim 26

The invention of claim 21 wherein said one end of said elongate strip extends radially to define an abutment engageable by the other of said ends.

Claim 27

The invention of claim 20 wherein said elongate strip defines a pair of opposite ends both engaging said radially outer wall, said elongate strip being secured to said outer wall adjacent one of said pair of ends, the other of said pair of ends slidably engaging said outer wall, an intermediate portion of said elongate strip defining a radius greater than the radius of said outer wall, said intermediate portion moving radially into and out of engagement with said outer wall in response to centrifugal force to move said valve means respectively between said first and said second positions.

Claim 28

The invention of claim 20 wherein said elongate strip defines a pair of opposite ends, said elongate strip being formed into a circular shape with said pair of opposite ends secured to said outer wall adjacent to one another, an intermediate portion of said elongate strip in said first position of said valve means confronting said passage opening on said outer wall in spaced relation thereto, said elongate strip including a pair of elastic sections between said intermediate portion and said pair of opposite ends to allow relative movement therebetween, said intermediate portion moving radially outwardly in response to centrifugal force to engage said outer wall in said second position of said valve means.

Claim 29

A combustion turbine machine including structure having a housing defining an opening, a relatively rotatable shaft means received in said opening, and a seal apparatus circumscribing said shaft means and cooperating with said housing and said shaft means to substantially prevent leakage of a liquid through said opening in response to a flow of pressurized sealing fluid to said seal apparatus, and centrifugally responsive valve means upstream of said seal apparatus and rotating to control said sealing fluid flow as a function of rotational speed.

Claim 30

A combustion turbine machine including structure having a housing defining an opening, a relatively rotatable shaft means received in said opening, and a seal apparatus circumscribing said shaft means and cooperating with said housing and said shaft means to substantially prevent leakage of a liquid through said opening in response to a flow of pressurized sealing fluid to said seal apparatus, and centrifugally responsive valve means upstream of said seal apparatus and rotating to control said sealing fluid flow as a function of rotational speed.

Claim 33

In a turbo machine having a housing journaling a shaft means, said shaft means carrying a compressor wheel discharging pressurized air to a discharge area; the method of forming a seal between said housing and said shaft means which is resistant to the leakage of a liquid therepast, said method comprising the steps of: forming a sealing structure between said housing and said shaft means, said sealing structure resisting the leakage of said liquid therepast in response to a flow of pressurized air into a chamber of said sealing structure; forming flow path means within said shaft means leading from said discharge area to said chamber of said sealing structure for communicating a flow of said pressurized air to the latter; disposing a centrifugally responsive valve means in said flow path means for controlling said flow of pressurized air as a function of shaft means rotational speed; and utilizing said flow of pressurized air to resist leakage of a liquid between said housing and shaft means at said seal structure.

Claim 34

In a turbo machine having a housing journaling a shaft means, said shaft means carrying a compressor wheel discharging pressurized air to a discharge area; the method of forming a seal between said housing and said shaft means which is resistant to the leakage of a liquid therepast, said method comprising the steps of: forming a sealing structure between said housing and said shaft means, said sealing structure resisting the leakage of said liquid therepast in response to a flow of pressurized air into a chamber of said sealing structure; forming flow path means within said shaft means leading from said discharge area to said chamber of said sealing structure for communicating a flow of said pressurized air to the latter; disposing a centrifugally responsive valve means in said flow path means for controlling said flow of pressurized air as a function of shaft means rotational speed; and utilizing said flow of pressurized air to resist leakage of a liquid between said housing and shaft means at said seal structure.

Claim 35

The method of claim 16 wherein said step of disposing centrifugally responsive valve means includes: forming a circumferentially extending annular chamber within said shaft means and substantially coaxial therewith, said annular chamber defining a part of said flow path means and including a radially outer circumferential wall, said outer wall defining a passage opening thereon and leading to said chamber of said sealing structure; and disposing a circumferentially extending resilient element within said annular chamber, said resilient element including a portion which is yieldably biased radially inwardly to a first position spaced from said passage opening, said portion of said resilient element shifting radially outwardly to a seoond position wherein said portion spans said passage opening in response to centrifugal force.

Claim 36

The method claim 29 wherein said step of forming flow path means within said shaft means includes: forming a clearance space extending radially inwardly from said discharge area toward said shaft adjacent a back face of said compressor wheel; forming a cavity within said shaft means communicating with said clearance space; and forming a passage within said shaft means communicating said cavity with said annular chamber.

Claim 37

The method of claim 30 wherein said step of forming a sealing structure includes: forming an axially extending circumferential surface on said shaft means; forming an axially and circumferentially extending wall part of said housing to define an opening receiving said shaft means, said wall being spaced radially outwardly of and confronting said shaft means to define an axially extending clearance therebetween; forming at least a pair of circumferentially extending and axially spaced apart knife-edge elements extending radially between said wall and shaft means for cooperating therewith to substantially define said chamber of said sealing structure, said sealing structure chamber circumscribing said shaft means.