초록 ▼

A modulating relief valve comprising a main relief valve and a dome pressure control system. The main relief valve has an inlet subject to system pressure, an outlet, a valve member normally sealing the inlet, a piston that rises and falls wit the valve member, and a dome adjacent to the piston, the

A modulating relief valve comprising a main relief valve and a dome pressure control system. The main relief valve has an inlet subject to system pressure, an outlet, a valve member normally sealing the inlet, a piston that rises and falls wit the valve member, and a dome adjacent to the piston, the dome having a dome pressure. The dome pressure control system is attached to the main relief valve. In one embodiment, the dome pressure control system has a body, a beam inside the body attached to the body at a pivot point, an input pressure module creating a first force on the beam, the first force being related to the system pressure and tending to rotate the beam in a first direction, a mechanism for setting a set-point pressure, the set-point pressure creating a second force on the beam, tending to rotate the beam in a second direction opposite the first direction, a control valve that exerts an additional force on the beam tending to rotate the beam in the first direction, the additional force having one component that is related to the dome pressure, the control valve allowing dome pressure to be exhausted when the beam is rotated in the first direction thereby allowing the main valve member to open, and the control valve allowing system pressure to pressurize the dome when the beam is rotated in the second direction. In another embodiment, the dome pressure control system further includes a negative feedback system. In another embodiment, the dome pressure control system does not include a beam and is instead configured in a stacked arrangement.

대표청구항 ▼

[ What is claimed is:] [18.] A modulating relief valve for use on a pressure vessel having a system pressure, the modulating relief valve comprising:a) a main relief valve having:i) an inlet subject to the system pressure,ii) an outlet,iii) a valve member normally sealing the inlet,iv) a piston that

[ What is claimed is:] [18.] A modulating relief valve for use on a pressure vessel having a system pressure, the modulating relief valve comprising:a) a main relief valve having:i) an inlet subject to the system pressure,ii) an outlet,iii) a valve member normally sealing the inlet,iv) a piston that rises and falls with the valve member, andv) a dome adjacent to the piston, the dome having a dome pressure; andb) a dome pressure control system attached to the main relief valve, the dome pressure control system having:i) a body,ii) an input pressure module at least partially in the body creating a first force proportional to the system pressure and tending to allow dome pressure to exhaust,iii) a mechanism for setting a set-point pressure, the set-point pressure creating a second force tending to prevent dome pressure exhaust, andiv) a control valve having an exhaust valve seat and an exhaust valve member against which the dome pressure applies a net force, the control valve being at least partially in the body, wherein an additional force tends to allow exhaust of the dome pressure by tending to remove the exhaust valve member from the exhaust valve seat, the additional force having one component that is proportional to the dome pressure, the control valve allowing dome pressure to be exhausted when there is a difference between the system pressure and the set-point pressure such that the first force and the additional force exceed the second force, thereby allowing the main valve member to open an amount, the amount the main valve opens being proportional to the difference between the system pressure and the set-point pressure, and the control valve allowing system pressure to pressurize the dome when the second force exceeds the sum of the first force and the additional force.