Valve actuator and pilot assembly therefor

In a flow line actuator respondable to fluid pressure for manipulation of operative means of a valve between open and closed position, a pilot assembly comprising:

• a housing;
• valve means within said housing having valve seat means thereon;
• normally free traveling spherical members immediate said valve means defining valve head means and sealingly engagable on said valve seat means and wipable thereoff to selectively open and close said valve means to control fluid flow therethrough;
• spool means shiftable in one of linear and rotational directions within said housing immediate said valve means and not constrained against the other of linear and rotational directions, said spool means being operably associated with said valve seat means and said valve head means to permit selective engagement of said valve head means onto said valve seat means upon only one of linear and rotational shifting of said spool means, the selective engagement of said head and seat means being sealingly insensitive to the other of linear and rotational shifting of said spool means, said spool means being selectively shiftable to manipulate said operative means between open and closed position.

In a flow line actuator respondable to a source of fluid pressure for manipulation of operative means of a valve between open and closed position, a pilot assembly comprising:

• a housing;
• pilot means within said housing having valve seat means thereon;
• normally free traveling spherical members immediate said pilot means defining valve head means and sealingly engagable onto said pilot means and wipable thereoff to selectively open and close said pilot means to control fluid flow therethrough, said pilot means comprising first, second and third pilot members, said first pilot member being selectively communicable with said source of fluid pressure, one of said second and third pilot members having one of said spherical members in sealing engaged position on its seat and the other of said second and third pilot members having said spherical members in disengaged position with respect to its seat when said first pilot member is in fluid communication with the source fluid pressure to permit said source fluid pressure to be transmitted through said pilot means and act within said actuator to move said operative means to one of open and closed position, said second and said third pilot members each having its respective spherical members in disengaged position with respect to its seat when said first pilot member has one of said spherical members in sealing engaged position on its seat whereby fluid pressure within said actuator is transmitted within said pilot means to act within said actuator to move said operative means to one of open and closed position, one of said second and third pilot members having one of said spherical members in sealing engaged position on its seat when said first pilot member has its respective spherical members in disengaged position with respect to its seat to isolate fluid pressure within said actuator from said source of fluid pressure and permit fluid pressure within said actuator to be transmitted through said pilot means and to act within said actuator to move said operative means to one of open and closed position.

In a flow line actuator respondable to a source of fluid pressure for manipulation of operative means of a valve between open and closed position, a pilot assembly comprising:

• a housing;
• pilot means within said housing having valve seat means thereon;
• normally free traveling spherical members immediate said pilot means defining valve head means and sealingly engagable onto said pilot means and wipable thereoff to selectively open and close said pilot means to control fluid flow therethrough;
• said pilot means having first, second and third pilot members, said first pilot member being selectively communicable with said source of fluid pressure, one of said second and third pilot members having one of said spherical members in sealingly engaged position on its seat and the other of said second and third pilot members having said spherical members in disengaged position with respect to its seat when said first pilot member is in fluid communication with the source of fluid pressure to permit said source of fluid pressure to be transmitted through said pilot means and to act within said actuator to move said operative means to one of open and closed position, said second and said third pilot members each having its respective spherical members in disengaged position with respect to its seat when said first pilot member has one of said spherical members in sealing engaged position on its seat to permit fluid pressure within said actuator to be transmitted within said pilot means and to act within said actuator to move said operative means to one of open and closed position, one of said second and third pilot members having one of said spherical members in sealing engaged position on its seat when said first pilot member has its respective spherical members in disengaged position with respect to its seat to isolate fluid pressure within said actuator from said source of fluid pressure and permit fluid pressure within said actuator to be transmitted through said pilot means and to act within said actuator to move said operative means to one of open and closed position;
• pilot spool means within said housing immediate said pilot means and operably associatable with said pilot means and said spherical members to permit selective engagement of said spherical members onto said valve seat means of said pilot means;
• stem means within said housing and engaged to said pilot spool means;
• means within said housing and carried around said stem for resisting travel of said spool means in a first direction;
• and differential area means across said spool means responsive to differential pressure to selectively overcome travel resistance of said spool means by said resisting means and to shift said spool means in a second direction, said spool means being selectively shiftable in response to variation of fluid pressure to permit fluid pressure to act within said actuator to manipulate said operative means between open and closed position, said spool means being shiftable in a first direction to normal position by increase of source fluid pressure sufficient to overcome resistance to travel of said spool means by said resisting means to permit said first pilot member to be communicable with said source of fluid pressure, to permit one of the spherical members of one of said second and third pilot members to be in sealing engaged position on its seat, and to permit the spherical members of the other of said second and third pilot members to be in disengaged position with respect to its seat to permit said source fluid pressure to be transmitted through said pilot means and to act within said actuator to move said operative means to one of open and closed position, said spool means being shiftable to a second position overcoming the resistance afforded by said spool travel resisting means when source fluid pressure exceeds a predetermined value to permit the respective spherical members of each of said second and third pilot members to be in disengaged position with respect to its seat and to permit one of said spherical members to be in sealing engaged position on the seat of the first pilot member to permit fluid pressure to be transmitted within said pilot means and to act within said actuator to move said operative means to one of open and closed position, the spool means being shiftable to a third position by decrease in source fluid pressure below a predetermined value and by said spool travel resisting means to permit one of said spherical members to be in sealing engaged position on the seat of one of said second and third pilot members and to permit the spherical members to be disengaged from the seat of said first pilot member whereby fluid pressure within said actuator is isolated from said source of fluid pressure and fluid pressure within said actuator is transmittable through said pilot means to act within said actuator to move said operative means to one of open and closed position.

In a flow line actuator respondable to a source of fluid pressure for moving an operative means of a valve between open and closed position, a pilot control assembly comprising:

• a housing having flow passageways therethrough;
• valve means with valve seat members having flow paths therein selectively communicable with said flow passageways, each of said valve members defining thereon a seal bore;
• normally free traveling spherical head members immediate each of said valve seat members for selective sealing engagement on the seal bore of each of said valve seat members;
• and shiftable spool means carrying said spherical members and operably responsive to fluid pressure to selectively permit movement of at least one of said valve head members to sealing engagement on the seal bore of at least one of said valve seat members, said valve means comprising:
• first, second and third valve seat and head members, said first seat member being selectively communicable with said source of fluid pressure, one of said second and third seat members being in sealing engaged position with one of its head members when said first seat member is in fluid communication with the source of fluid pressure to permit said source of fluid pressure to be transmitted through said pilot means and to act within said actuator to move said operative means to one of open and closed position, each of said second and third valve seat members being in disengaged position with its valve head member when said first valve seat is engaged with one of its valve heads to permit fluid pressure in said actuator to be transmitted within said pilot means and to act within said actuator to move said operative means to one of open and closed position, one of said second and third valve seats having one of its valve heads in sealing engaged position thereon when said first valve seat is disengaged from its valve heads to isolate fluid pressure within said actuator from said source of fluid pressure to permit fluid pressure within said actuator to be transmitted through said pilot means and to act within said actuator to move said operative means to one of open and closed position.

In a flow line actuator respondable to a source of fluid pressure for moving an operative means of a valve between open and closed position, a pilot control assembly comprising:

• a housing having flow passageways therethrough;
• a plurality of valve means with valve seat members having flow paths therein selectively communicable with said flow passageways, each of said valve seat members defining thereon a seal bore;
• normally free traveling spherical valve head members immediate each of said valve seat members for selective sealing engagement on the seal bore of each of said valve seat members;
• and spool means carrying said spherical members and operably responsive to fluid pressure to selectively move at least one of said valve head members to sealing engagement on the seal bore of at least one of said valve seat members and to selectively move said valve head members to disengaged position from the seal bore of another of said valve seat members, said spool means being shiftable in one of linear and rotational directions and not constrained against the other of linear and rotational directions, the selective engagement of said head and seat means being sealingly insensitive to the other of linear and rotational shifting of said spool means.

In a flow line actuator respondable to a source of fluid pressure for manipulation of operative means of a valve between open and closed position, a pilot assembly comprising:

• a housing;
• pilot means within said housing having valve seat means thereon;
• normally free traveling spherical members immediate said pilot means defining valve head means and sealingly engagable onto said pilot means and wipable thereoff to selectively open and close said pilot means to control fluid flow therethrough;
• pilot spool means within said housing immediate said pilot means and operably associatable with said pilot means and said spherical members to permit selective engagement of said spherical members onto said valve seat means of said pilot means, said spool means being selectively shiftable in one of linear and rotational directions in response to variation of said fluid pressure and not constrained against the other of linear and rotational directions to permit said fluid pressure to act within said actuator to manipulate said operative means between open and closed position;
• stem means within said housing and engaged to said spool;
• means within said housing and carried around said stem means for resisting travel of said spool means in a first direction;
• and piston means on said spool means having equivalent differential areas responsive to fluid pressure variance to selectively overcome travel resistance of said spool means and to shift said spool means in a second direction, the selective engagement of said head and seat means being sealingly insensitive to the other of linear and rotational shifting of said spool means.

A pilot assembly respondable to a source of fluid pressure for manipulation of an operative means of a valve between open and closed position, comprising:

• a housing;
• pilot means within said housing having valve seat means thereon;
• normally free traveling spherical members immediate said pilot means defining valve head means and sealingly engagable on said pilot means and wipable thereoff to selectively open and close said pilot means to control fluid flow therethrough;
• pilot spool means within said housing immediate said pilot means and operably associatable with said pilot means and said spherical members to permit selective engagement of said spherical members onto said valve seat means of said pilot means, said spool means being selectively shiftable in one of linear and rotational directions in response to variation of said fluid pressure and not constrained against the other of linear and rotational directions to permit said fluid pressure to act within said pilot assembly to manipulate said operative means between open and closed position, the selective engagement of said head and seat means being sealingly insensitive to the other of linear and rotational shifting of said spool means.

A pilot control assembly for moving an operative means of a valve between open and closed position and respondable to a source of fluid pressure, said pilot control assembly comprising:

• a housing having flow passageways therethrough;
• valve means with valve seat members having flow paths therein selectively communicable with said flow passageways, each of said valve members defining thereon a seal bore;
• normally free traveling spherical valve head members immediate each of said valve seat members for selective sealing engagement on the seal bore of each of said valve seat members;
• and spool means carrying said spherical members shiftable in one of linear and rotational directions and not constrained against the other of linear and rotational directions, said spool means being operably responsive to fluid pressure to selectively move at least one of said valve head members to sealing engagement on the seal bore of at least one of said valve seat members to move the operative means between open and closed position, the selective engagement of said head and seat means being sealingly insensitive to the other of linear and rotational shifting of said spool means.

In a flow line actuator respondable to a source of fluid pressure for moving an operative means of a valve between open and closed position, a pilot control assembly comprising:

• a housing having flow passageway members therethrough;
• valve means with valve seat members having flow paths therein selectively communicable with said flow passageway members, each of said valve seat members defining thereon a seal bore;
• normally free traveling spherical valve head members immediate each of said valve seat members for selective sealing engagement on the seal bore of each of said valve seat members;
• shiftable spool means carrying said spherical members and operably responsive to fluid pressure to selectively permit movement of at least one of said valve head members to sealing engagement on the seal bore of at least one of said valve seat members;
• and check valve means within one of said flow passageway members to permit transmission of fluid pressure from said source therethrough in a first direction and to prevent transmission of fluid pressure from said source therethrough in a second direction.

A pilot assembly for manipulation of a valve operative means between open and closed position in response to detection of pressure in excess of a preselected operating range, said pilot assembly comprising:

• a housing;
• first and second valve means within said housing having valve seat means thereon;
• normally free traveling spherical members immediate said valve means defining valve head means and sealingly engagable onto said valve seat means and wipable thereoff to selectively open and close said valve means to control fluid flow therethrough;
• spool means shiftable in one of linear and rotational directions within said housing immediate said valve means and not constrained against the other of linear and rotational directions, said spool means being operably associated with said valve seat means and said valve head means to permit selective movement of said head means to said seat means and selective engagement of said head and seat means upon only one of linear and rotational shifting of said spool means, the selective engagement of said head and seat means being sealingly insensitive to the other of linear and rotational shifting of said spool means.