Traveling finger lock for an actuator

A method of locking a linear actuator, the method comprising:

• urging axial movement of a piston within an axial cavity defined by an inner surface of a housing, away from a first piston position and toward a second piston position, wherein the piston has a first piston end and a second piston end axially opposite the first piston end;
• urging, by the piston, axial movement of a lock finger affixed to the first piston end at a first finger end and extending away from the piston to a second finger end in an extended configuration;
• contacting, by the second finger end, a face defined by the inner surface between a first housing portion wherein the axial cavity has a first lateral size to a second housing portion wherein the axial cavity has a second lateral size that is larger than the first lateral size;
• preventing, by the contacting, movement of the piston to the second piston position, the preventing comprising:
• contacting, by the second finger end, a second face defined by the piston;
• and
• transferring, by the second finger end, an axial force of the piston to the housing;
• urging movement of a sleeve axially from a first sleeve position to a second sleeve position within the axial cavity;
• contacting, by the sleeve, the lock finger;
• urging, by the sleeve, the lock finger from the extended configuration to a retracted configuration in which the lock finger fits within the first housing portion;
• and
• moving the piston to the second piston position.

A thrust reverser actuator system comprising:

• an airframe structure;
• a thrust reverser cowl configured to move relative to the airframe structure;
• a linear actuator configured to move the thrust reverser cowl relative to the airframe structure, and comprising:
• a housing having an inner surface defining an axial cavity comprising:
• a first housing portion wherein the axial cavity has a first lateral size;
• a second housing portion wherein the axial cavity has a second lateral size that is larger than the first lateral size;
• and
• a face defined by the inner surface from the first housing portion to the second housing portion;
• a piston having a first piston end and a second piston end axially opposite the first piston end, wherein the piston is configured for axial movement within the axial cavity between a first piston position and a second piston position;
• and
• a lock apparatus comprising:
• a lock finger affixed to the first piston end at a first finger end and extending away from the piston to a second finger end, wherein the second finger end is configured to contact the face axially and contact the piston axially in an extended configuration and fit within the first housing portion in a retracted configuration;
• and
• a sleeve arranged within the second housing portion and configured to move axially within the second housing portion between a first sleeve position in which the lock finger is permitted to extend to the extended configuration and a second sleeve position configured to contact the lock finger and urge the lock finger to the retracted configuration.