Valves And Valve Actuation Patents (Class 251)
Blow-out preventers (i.e., cooperating segments of annulus) (Class 251/1.1)
Pattern tracer controlled actuator (Class 251/3)
Tube compressors (Class 251/4)
Heat or buoyancy motor actuated (Class 251/11)
Fluid actuated or retarded (Class 251/12)
With non-fluid retarder (Class 251/64)
Permanent or constantly energized magnet actuator (Class 251/65)
Biased trip (Class 251/66)
With snap action (Class 251/75)
Impact type actuator (Class 251/76)
Lost motion between actuator and valve (Class 251/77)
Valve head movably connected for accommodation to seat (Class 251/84)
With means for blocking or disabling actuator (Class 251/89)
With restrictor in parallel to main valve (Class 251/117)
With material guide or restrictor (Class 251/118)
With detachable actuator and means to prevent leakage when actuator is detached (Class 251/128)
Electrically actuated valve (Class 251/129.01)
With correlated flow path (Class 251/142)
With means to increase head and seat contact pressure (Class 251/157)
With selective flow regulation (Class 251/205)
Sequential opening or closing of serial ports in single flow line (e.g., anti-scoring) (Class 251/210)
Serial alternately closed ports (Class 251/211)
Relatively movable valve elements form single port closure (e.g., iris diaphragm) (Class 251/212)
Mechanical movement actuator (Class 251/213)
Balanced valves (Class 251/281)
Limit stop (Class 251/284)
Valve actuable from plural positions (Class 251/289)
Plural selective neutral positions for valve or actuator (Class 251/290)
Detachable actuator (Class 251/291)
Extension for actuator (Class 251/293)
Flexible actuator (e.g., bowden wire; chain) (Class 251/294)
Pedal actuator (Class 251/295)
Plural motions of actuator (Class 251/296)
With friction detent (Class 251/297)
Pivoted valves (Class 251/298)
Rotary valves (Class 251/304)
Reciprocating valve (Class 251/318)
Hermetic flexible wall seal for actuator (Class 251/335.1)
Biased valve (Class 251/336)
Valve actuator extending through fluid inlet or outlet (Class 251/339)
Valve actuator surrounding pipe, inlet or outlet (Class 251/340)
Valve actuator is valve casing or extension thereof (Class 251/341)
Valve actuator is inlet or outlet (Class 251/349)
With actuation lubricating means (Class 251/355)
Valve (Class 251/356)
Miscellaneous (Class 251/369)

Cross-Reference Art Collections

Valves with o-rings (Class 251/900)
Curtain type valves (Class 251/901)
Springs employed as valves (Class 251/902)
Needle valves (Class 251/903)
Snap fit plug valves (Class 251/904)
Movable coil electrical actuator (e.g., voice coil) (Class 251/905)

Foreign Patent Art Collections

Class-related foreign documents (Class 251/FOR000)