초록 ▼

A statically and dynamically pressure balanced fluid control valve. The valve contains a spool that is moved within an inner chamber of a valve housing by a pair of solenoids. The ports are symmetrically located on each side of a center port, wherein the resultant fluid forces on the spool are in op

A statically and dynamically pressure balanced fluid control valve. The valve contains a spool that is moved within an inner chamber of a valve housing by a pair of solenoids. The ports are symmetrically located on each side of a center port, wherein the resultant fluid forces on the spool are in opposite directions. The opposing forces create a net fluid force of approximately zero, so that the spool is dynamically pressure balanced when the valve is switched to a new position. The spool also has an inner channel and a pair of end openings that are in fluid communication with the inner chamber of the valve. When the spool is pulled to a new position, the end openings and inner channel allow fluid within the inner chamber to flow out of the space between the end of the spool and the housing. The flow of fluid through the end openings and inner channel prevent the formation of hydrostatic fluid pressure that will counteract the movement of the spool. The end openings and inner channel thus statically pressure balance the spool within the valve.

대표청구항 ▼

A fluid control valve, comprising: a housing that has a first external port and a pair of second external ports; a spool that can move between a first position and a second position within said housing, said spool having a ridge that cooperates with said housing to prevent fluid communication betwee

A fluid control valve, comprising: a housing that has a first external port and a pair of second external ports; a spool that can move between a first position and a second position within said housing, said spool having a ridge that cooperates with said housing to prevent fluid communication between said first external ports and said second external ports when said spool is in the first position, and a plurality of outer grooves that each have a pair of opposing walls and which provide fluid communication between said first external port and both second external ports when said spool is in the second position, wherein fluid flows between said first and second external ports such that the fluid exerts essentially equal and opposite fluid forces on said walls of said outer grooves; and, a first solenoid that moves said spool to the first position.