US 12,546,339 B1Granted

Actuator load and slew rate limiting via pressure throttling shutoff valve

AssigneeHamilton Sundstrand Corporation

InventorsFrank Perrelli, Sachin Ramprashad

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Abstract

A system includes a control valve with a first control port and a second control port. An actuator of the system includes a piston between an extend chamber and a retract chamber. The system also includes a shutoff valve fluidically connected between the control valve and the actuator. The shutoff valve is passively controlled by a pressure differential between the extend chamber and the retract chamber. If the pressure differential between the extend chamber and the retract chamber exceeds normal operating pressures for the actuator, the shutoff valve closes to stop pressure and flow communication between the control valve and the actuator, thereby pausing the actuator. When the pressure differential between the extend chamber and the retract chamber returns to the normal operating pressures for the actuator, the shutoff valve passively returns to an equilibrium position that allows the actuator to resume operation.

Claims20

Dependent claims

An actuation system comprising:

an electrohydraulic servo valve comprising:
a first control port;
and
a second control port;
a hydraulic actuator comprising:
an actuator housing;
a piston inside the actuator housing;
an extend chamber in the actuator housing on a first side of the piston;
a retract chamber in the actuator housing on a second side of the piston;
and
a linkage arm extending from the piston through the actuator housing;
a shutoff valve comprising:
a valve housing extending axially from a first end of the shutoff valve to a second end of the shutoff valve relative to a center axis of the shutoff valve;
a first valve seat formed in the valve housing and axially between the first end and the second end of the shutoff valve;
a first port extending through the valve housing and axially between the first end of the shutoff valve and the first valve seat, wherein the first port is fluidically connected to the extend chamber of the hydraulic actuator;
a second port extending through the valve housing and axially between the first valve seat and the second end of the shutoff valve, wherein the second port is fluidically connected to the first control port;
and
a third port extending through the valve housing and axially between the second port and the second end of the shutoff valve, wherein the third port is fluidically connected to the second control port or the retract chamber of the hydraulic actuator;
a spool inside the valve housing and comprising:
a land in the valve housing and axially between the first valve seat and the second end of the shutoff valve;
and
a first spring between the spool and the valve housing, wherein the first spring biases the land to an equilibrium position between the second port and the third port.

19 more elements

A shutoff valve comprising:

a valve housing extending axially from a first end of the shutoff valve to a second end of the shutoff valve relative to a center axis of the shutoff valve;
a first valve seat formed in the valve housing and axially between the first end and the second end of the shutoff valve;
a first port extending through the valve housing and axially between the first end of the shutoff valve and the first valve seat;
a second port extending through the valve housing and axially between the first valve seat and the second end of the shutoff valve;
and
a third port extending through the valve housing and axially between the second port and the second end of the shutoff valve;
a spool inside the valve housing and comprising:
a land in the valve housing and axially between the first valve seat and the second end of the shutoff valve;
and
a first spring between the spool and the valve housing, wherein the first spring biases the land to an equilibrium position between the second port and the third port.

7 more elements

Dependencies are inferred from the claim text.