US 8,262,058 B2Granted

Balanced pilot operated check valve

OwnerNorbert J. Kotinventor

Life of this patent

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Abstract

A valve assembly includes a check valve element in an output chamber. The check valve element opens to permit forward flow of fluid under pressure in the output chamber from an input port to an output port. The check valve element closes to block back flow of fluid under pressure in the output chamber from the output port toward the input port. The back flow of fluid under pressure exerts a closing force upon the check valve element from within the output chamber. A counter force generating element, or pilot element, communicates with the valve element, to selectively open the valve, even in the presence of back flow pressure. The counter force generating element may apply a counter force to the check valve element, which urges the valve element toward the opened condition. The counter force may be less than the closing force, so the check valve element remains closed.

Claims12

Dependent claims

A valve comprising:

a valve body comprising:
a cartridge bore comprising a piston bore, an input counterbore, an output counterbore, and a bearing sleeve counterbore, said input counterbore and said output counterbore meeting at a sealing ledge;
an input reentrant bore which intersects said input counterbore;
an output reentrant bore which intersects said output counterbore;
and
a pilot reentrant bore which intersects said piston bore;
and
a counterbalance reentrant bore, said counterbalance reentrant bore intersecting said pilot reentrant bore and said output reentrant bore and said counterbalance reentrant bore being free of obstruction between said pilot reentrant bore and said output reentrant bore;
a piston cartridge disposed at least partially within said cartridge bore, said piston cartridge comprising:
a longitudinal piston rod;
a first piston head secured to one end of said piston rod;
a second piston head secured to a second end of said piston rod, said second piston head disposed in said piston bore;
a poppet member slidably disposed on said piston rod within said output counterbore;
and
a poppet bias spring located between said poppet member and said first piston head biasing said poppet member in a poppet bias direction against said sealing ledge;
an end cap spring acting against said first piston head, biasing said piston rod in said poppet bias direction;
and
a bearing sleeve inserted into said bearing counterbore, extending into said output counterbore,
wherein said first piston head is disposed in said bearing sleeve and said second piston head is disposed in said piston bore.

16 more elements

A valve comprising:

a valve body comprising:
a cartridge bore comprising a piston bore, an input counterbore, an output counterbore, and a bearing sleeve counterbore, said input counterbore and said output counterbore meeting at a sealing ledge;
an input reentrant bore which intersects said input counterbore;
an output reentrant bore which intersects said output counterbore;
a sensor reentrant bore formed into said valve body, said sensor reentrant bore in fluid communication with said output counterbore and spaced from said output reentrant bore;
and
a pilot reentrant bore which intersects said piston bore;
a piston cartridge disposed at least partially within said cartridge bore, said piston cartridge comprising:
a longitudinal piston rod;
a first piston head secured to one end of said piston rod;
a second piston head secured to a second end of said piston rod, said second piston head disposed in said piston bore;
a poppet member slidably disposed on said piston rod within said output counterbore;
and
a poppet bias spring located between said poppet member and said first piston head biasing said poppet member in a poppet bias direction against said sealing ledge;
an end cap spring acting against said first piston head, biasing said piston rod in said poppet bias direction;
and
a bearing sleeve inserted into said bearing counterbore, extending into said output counterbore,
wherein said first piston head is disposed in said bearing sleeve and said second piston head is disposed in said piston bore.

15 more elements

Dependencies are inferred from the claim text.

Facts

Application: 12/583,980Filed 28 Aug 2009 · us provisional application
Priority: 28 Aug 2008
Published: US 2010/0059125 A111 Mar 2010
Granted: 11 Sep 2012
Term ends: Not estimatedThe source records don’t support an estimate.

Classification11 codes

F16K 27/003
Construction of housing ; Use of materials therefor: housing formed from a plurality of the same valve elements
F15B 13/01
Details of servomotor systems ; Valves for servomotor systems: locking-valves or other detent i.e. load-holding devices
F16K 31/1221
The fluid acting on a piston: one side of the piston being spring-loaded
F16K 31/124
The fluid acting on a piston: servo actuated