Plug valve having a dual diaphragm three position actuator

Claim 2

The combination of a rotary plug valve, a multi-position expansible chamber vacuum actuator and a common support mounting both said valve and actuator in assembled operative relationship; said valve including a housing rigidly secured to said support and a control lever to rotatE said plug; said actuator comprising housing means secured to said support, at least two diaphragms secured within said housing to define two vacuum operating chambers, one of said chambers located in the space between the two diaphragms, said diaphragms cooperating with said housing to provide fluid tight isolation between said operating chambers, means providing fluid communication through said housing into each of said operating chambers from the exterior of said housing, motion transmitting means secured at one end to one of said diaphragms exterior of said two operating chambers and projecting exterior of said housing,means coacting with said diaphragms urging them in a direction causing maximum extension of said motion transmitting means from said housing including a collapsible device located between and connected to both of said diaphragms enabling said diaphragms to move relatively toward and away from each other between a substantially fixed maximum distance at least when one of said chambers is selectively subjected to vacuum and a closely spaced adjacent disposition of said two diaphragms at the end of said housing means opposite the motion transmitting means when both of said chambers are subjected to vacuum; a pivot connection between the other end of said motion transmitting means and said plug control lever; and said collapsible device permitting tilting of at least said one of said diaphragms and said motion transmitting means relative to said actuator housing means to accommodate an arcuate swinging of said pivot connection about the axis of the rotary plug of said rotary plug valve as the actuator moves said rotary plug through an intermediate flow control position between its operating limit positions.

Claim 3

The plug valve and actuator combination as deffined in claim 1, wherein said collapsible device located between and connected to said two diaphragms comprises diaphragm support plate means secured to each of said diaphragms in facing relationship, anchor means on each of said support plate means, a collapsing link secured to both of said anchor means, and means for positively preventing a non-collapsing condition of said collapsing link when disposed in its extended position.

Claim 4

The plug valve and actuator combination as defined in claim 2, wherein said collapsing link comprises two U-shaped bails, the stems thereof pivotally connected to said anchor means, said means for positively preventing a non-collapsing condition of said link comprising a bracket hinging the center portions of said U-shaped bails, and having portions cooperating with said bails limiting extension thereof to less than a 180* disposition.

Claim 5

The plug valve and actuator combination as defined in claim 1, wherein said motion transmitting means comprises an elongate rod rigidly secured at said one end to said one of said diaphragms.

Claim 6

The plug valve and actuator combination as defined in claim 4, wherein said pivot connection between the other end of said motion transmitting means and said plug control lever comprises a cooperating pin and aperture connection between the outer free end of said elongate rod and said plug control lever.

Claim 7

The plug valve and actuator combination as recited in claim 5, wherein said cooperating pin and aperture connection between the outer free end of said elongate rod and said plug control lever comprises an L-shaped extension formed on said elongate rod free end and means defining a mating aperture for said L-shaped extension in the outer free end of said plug control lever.

Claim 8

The combination of a rotary plug valve, an expansible chamber motor actuator and a common support mounting both said valve and actuator in assembled operative relationship; said valve including a housing rigidly secured to said support and a control lever to rotate said plug; said actuator comprising housing means secured to said support, at least two diaphragms mounted within said housing to define two operating chambers, one of said Chambers located in the space between the two diaphragms, said diaphragms cooperating with said housing to provide fluid tight isolation between said operating chambers, means providing fluid communication through said housing into each of said operating chambers from the exterior of said housing, motion transmitting means secured at one end to one of said diaphragms exterior of said operating chambers and projecting exterior of said housing, means coacting with said diaphragms urging them in a direction causing maximum extension of said motion transmitting means from said housing including a collapsible device located between and connected to said two diaphragms enabling said diaphragms to move relatively away from and toward each other between a substantially fixed maximum distance and a closely spaced adjacent disposition of said two diaphragms and resilient expansion coil spring means disposed in said operating chambers, said coil spring means together urging said diaphragms toward a maximum volume condition of said operating chambers; and a pivot connection between the other end of said motion transmitting means and said plug control lever; said collapsible device permitting tilting of at least said one of said diaphragms and said motion transmitting means relative to said actuator housing means to accommodate an arcuate swinging of said pivot connection about the axis of the rotary plug of said rotary plug valve as the actuator moves said rotary plug through an intermediate flow control position between its operating limit positions.

Claim 9

The combination of a rotary plug valve, an expansible chamber motor actuator and a common support mounting both said valve and actuator in assembled operative relationship; said valve including a housing rigidly secured to said support and a control lever to rotate said plug; said actuator comprising housing means secured to said support, at least two diaphragms mounted within said housing to define two operating chambers, one of said Chambers located in the space between the two diaphragms, said diaphragms cooperating with said housing to provide fluid tight isolation between said operating chambers, means providing fluid communication through said housing into each of said operating chambers from the exterior of said housing, motion transmitting means secured at one end to one of said diaphragms exterior of said operating chambers and projecting exterior of said housing, means coacting with said diaphragms urging them in a direction causing maximum extension of said motion transmitting means from said housing including a collapsible device located between and connected to said two diaphragms enabling said diaphragms to move relatively away from and toward each other between a substantially fixed maximum distance and a closely spaced adjacent disposition of said two diaphragms and resilient expansion coil spring means disposed in said operating chambers, said coil spring means together urging said diaphragms toward a maximum volume condition of said operating chambers; and a pivot connection between the other end of said motion transmitting means and said plug control lever; said collapsible device permitting tilting of at least said one of said diaphragms and said motion transmitting means relative to said actuator housing means to accommodate an arcuate swinging of said pivot connection about the axis of the rotary plug of said rotary plug valve as the actuator moves said rotary plug through an intermediate flow control position between its operating limit positions.

Claim 10

The plug valve and actuator combination as defined in claim 7, wherein said means providing fluid communication through said housing into each of said operating chambers from the exterior of said housing comprise independent piping means connected to independent vacuum sources for selective and combined evacuation of said operating chambers against the urging of said resilient expansion coil spring means.

Claim 11

The combination of a rotary plug valve, an expansible chamber motor actuator and a common support mounting both said valve and actuator in assembled operative relationship; said valve including a housing rigidly secured to said support and a control lever to rotate said plug; said actuator comprising housing means secured to said support, at least two diaphragms mounted within said housing to define two operating chambers, one of said chambers located in the space between the two diaphragms, said diaphragms cooperating with said housing to provide fluid tight isolation between said operating chambers, means providing fluid communication through said housing into each of said operating chambers from the exterior of said housing, motion transmitting means secured at one end to one of said diaphragms exterior of said operating chambers and projecting exterior of said housing, means coacting with said diaphragms urging them in a direction causing maximum extension of said motion transmitting means from said housing including a collapsible device located between and connected to said two diaphragms enabling said diaphragms to move relatively away from and toward each other between a substantially fixed maximum distance and a closely spaced adjacent disposition of said two diaphragms; said housing means further comprise a spacer ring between said diaphragms urging the peripheries of said diaphragms into fluid seal relationship with said housing, one of said means providing fluid communication into said operating chambers comprising a portion of said spacer ring and including a fluid passageway through said spacer ring to said space between the two diaphragms: additional spacing means located between said diaphragms for preventing a fluid tight seal of one diaphragm against the other when said diaphragms are in said closely spaced adjacent disposition; a pivot connection between the other end of said motion transmitting means and said plug control lever; and said collapsible device permitting tilting of at least said one of said diapHragms and said motion transmitting means relative to said actuator housing means to accommodate an arcuate swinging of said pivot connection about the axis of the rotary plug of said rotary plug valve as the actuator moves said rotary plug through an intermediate flow control position between its operating limit positions.

Claim 12

The combination of a rotary plug valve, an expansible chamber motor actuator and a common support mounting both said valve and actuator in assembled operative relationship; said valve including a housing rigidly secured to said support and a control lever to rotate said plug; said actuator comprising housing means secured to said support, at least two diaphragms mounted within said housing to define two operating chambers, one of said chambers located in the space between the two diaphragms, said diaphragms cooperating with said housing to provide fluid tight isolation between said operating chambers, means providing fluid communication through said housing into each of said operating chambers from the exterior of said housing, motion transmitting means secured at one end to one of said diaphragms exterior of said operating chambers and projecting exterior of said housing, means coacting with said diaphragms urging them in a direction causing maximum extension of said motion transmitting means from said housing including a collapsible device located between and connected to said two diaphragms enabling said diaphragms to move relatively away from and toward each other between a substantially fixed maximum distance and a closely spaced adjacent disposition of said two diaphragms; said housing means further comprise a spacer ring between said diaphragms urging the peripheries of said diaphragms into fluid seal relationship with said housing, one of said means providing fluid communication into said operating chambers comprising a portion of said spacer ring and including a fluid passageway through said spacer ring to said space between the two diaphragms: additional spacing means located between said diaphragms for preventing a fluid tight seal of one diaphragm against the other when said diaphragms are in said closely spaced adjacent disposition; a pivot connection between the other end of said motion transmitting means and said plug control lever; and said collapsible device permitting tilting of at least said one of said diapHragms and said motion transmitting means relative to said actuator housing means to accommodate an arcuate swinging of said pivot connection about the axis of the rotary plug of said rotary plug valve as the actuator moves said rotary plug through an intermediate flow control position between its operating limit positions.

Claim 13

The combination of a rotary plug valve, an expansible chamber motor actuator and a common support mounting both said valve and actuator in assembled operative relationship; said valve including a housing rigidly secured to said support and a control lever to rotate said plug; said actuator comprising housing means secured to said support, at least two diaphragms mounted within said housing to define two operating chambers, one of said chambers located in the space between the two diaphragms, said diaphragms cooperating with said housing to provide fluid tight isolation between said operating chambers, means providing fluid communication through said housing into each of said operating chambers from the exterior of said housing, motion transmitting means secured at one end to one of said diaphragms exterior of said operating chambers and projecting exterior of said housing, means coacting with said diaphragms urging them in a direction causing maximum extension of said motion transmitting means from said housing including a collapsible device located between and connected to said two diaphragms enabling said diaphragms to move relatively away from and toward each other between a substantially fixed maximum distance and a closely spaced adjacent disposition of said two diaphragms; a pivot connection between the other end of said motion transmitting means and said plug control lever; said collapsible device comprising diaphragm support plate means secured to each of said diaphragms in facing relationship, anchor means on each of said support plate means, a collapsing link secured to both of said anchor means, and means for positively preventing a non-collapsing condition of said collapsing link when disposed in its extended position; and said collapsing link comprising two U-shaped bails, the stems thereof pivotally connected to said anchor means, said means for positively preventing a non-collapsing condition of said link comprising a bracket hinging the center portions of said U-shaped bails, and having portions cooperating with said bails limiting extension thereof to less than a 180* disposition: said collapsible device permitting tilting of at least said one of said diaphragms and said motion transmitting means relative to said actuator housing means to accommodate an arcuate swinging of said pivot connection about the axis of the rotary plug of said rotary plug valve as the actuator moves said rotary plug through an intermediate flow control position between its operating limit positions.

Claim 14

The combination of a rotary plug valve, an expansible chamber motor actuator and a common support mounting both said valve and actuator in assembled operative relationship; said valve including a housing rigidly secured to said support and a control lever to rotate said plug; said actuator comprising housing means secured to said support, at least two diaphragms mounted within said housing to define two operating chambers, one of said chambers located in the space between the two diaphragms, said diaphragms cooperating with said housing to provide fluid tight isolation between said operating chambers, means providing fluid communication through said housing into each of said operating chambers from the exterior of said housing, motion transmitting means secured at one end to one of said diaphragms exterior of said operating chambers and projecting exterior of said housing, means coacting with said diaphragms urging them in a direction causing maximum extension of said motion transmitting means from said housing including a collapsible device located between and connected to said two diaphragms enabling said diaphragms to move relatively away from and toward each other between a substantially fixed maximum distance and a closely spaced adjacent disposition of said two diaphragms; a pivot connection between the other end of said motion transmitting means and said plug control lever; said collapsible device comprising diaphragm support plate means secured to each of said diaphragms in facing relationship, anchor means on each of said support plate means, a collapsing link secured to both of said anchor means, and means for positively preventing a non-collapsing condition of said collapsing link when disposed in its extended position; and said collapsing link comprising two U-shaped bails, the stems thereof pivotally connected to said anchor means, said means for positively preventing a non-collapsing condition of said link comprising a bracket hinging the center portions of said U-shaped bails, and having portions cooperating with said bails limiting extension thereof to less than a 180* disposition: said collapsible device permitting tilting of at least said one of said diaphragms and said motion transmitting means relative to said actuator housing means to accommodate an arcuate swinging of said pivot connection about the axis of the rotary plug of said rotary plug valve as the actuator moves said rotary plug through an intermediate flow control position between its operating limit positions.