Back to results
US 5,174,339 AGranted
Fluid flow control valve
OwnerGerald W. Pickardinventor
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
OwnerGerald W. Pickardinventor
Estimating the term…
A fluid flow control valve includes a first spool member (1) the position of which controls an output fluid flow from the valve, and a control (23, MP) which controls the position of the first spool member (1), a second spool member (6), independent of the first spool member (2), is mounted in a common chamber (1) with the first spool member (6) so as to cooperate with an outlet port (15) through which the output fluid flow passes and to be movable in response to the pressure drop across the outlet port (15) so that its position is related to the output fluid flow. A feedback (22', 24) is responsive to the position of the second spool member (16) and provides an input to the control (23, MP) so that the control operates as a servo control system. The first spool member (2) includes two landed sections (3, 4) which are spaced apart with the second spool member (6) therebetween. The feedback is a mechanical feedback connection (24) to servo valve (23), and an electrical feedback signal (22') to a microprocessor (MP).
A fluid flow control valve comprising a first spool member the position of which controls an output fluid flow from the valve, said first spool member having two landed sections spaced apart in a chamber in said valve, control means which controls the position of the first spool member, a second spool member, independent of the first spool member, said second spool member being mounted in said chamber between the two landed sections of the first spool member so as to cooperate with an outlet port of said valve through which said output fluid flow passes and to be movable in response to a pressure drop across said outlet port so that the position of said second spool member is related to said output fluid flow, and feedback means which is responsive to the position of the second spool member and provides an input to said control means so that the control means operates as a servo control system.
Dependencies are inferred from the claim text.