Telescopic actuator with automatic locking

Patent metadata

Field	Value
Publication number	US-10801530-B2
Application number	US-201916410063-A
Country	US
Kind code	B2
Filing date	May 13, 2019
Priority date	May 18, 2018
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

The invention relates to a telescopic actuator comprising a cylinder ( 1 ) having a closed end ( 2 ) and an open end ( 3 ) for passing a hollow rod ( 4 ) mounted to slide axially in the cylinder. The actuator includes a central support ( 10 ) that extends from the closed end of the cylinder inside the rod and that carries obstacles ( 15 ) that are movable radially between a setback position leaving the rod free to slide and a projecting position in which the obstacles are engaged in a groove ( 9 ) in the rod in order to lock the rod axially relative to the cylinder, the flanks of the obstacles and of the groove being shaped so as to prevent any setting back of the obstacles by movement of the rod, the obstacles being arranged at the ends of spring blades ( 14 ) extending longitudinally and arranged to urge the obstacles from the setback position towards the projecting position, the central support carrying controlled means ( 20 ) for flexing the blades in order to cause the obstacles to be set back towards the setback position.

First claim

The invention claimed is:

1. A telescopic actuator comprising:
a cylinder having a closed end and an open end for passing a hollow rod mounted to slide axially in the cylinder; and
a central support that extends from the closed end of the cylinder inside the rod and that carries obstacles that are movable radially between a setback position leaving the rod free to slide and a projecting position in which the obstacles are engaged in a groove in the rod in order to lock the rod axially relative to the cylinder, flanks of the obstacles and of the groove being shaped so as to prevent any setting back of the obstacles by any movement of the rod, the obstacles being arranged at ends of spring blades extending longitudinally and arranged to urge the obstacles from the setback position towards the projecting position, the central support carrying a device that flexes the blades in response to a command in order to cause the obstacles to be set back towards the setback position.

2. A telescopic actuator according to claim 1 , wherein the device that flexes the blades comprises:
an unlocking piston mounted to slide axially on the central support between a rest position in which the unlocking position is remote from the obstacles, and an unlocking position in which a conical hollow end of the unlocking piston co-operates with fingers secured to each of the obstacles in order to cause the blades to flex and thus the obstacles to be set back from the projecting position to the setback position.

3. An actuator according to claim 1 , wherein the rod is associated with a piston, the groove for receiving the obstacles being made level with the piston.

4. An actuator according to claim 1 , wherein the rod is associated with a piston that includes a deflection cone for forcing the obstacles to be set back by flexing the blades while the rod is being retracted.

Assignees

• Safran Landing Systems

Inventors

• Lecourtier Gilbert
• Le Breton Arnaud

Classifications

• F15B2015/268

  Fluid supply for locking or release independent of actuator pressurisation · CPC title

• F15B15/261 Primary

  using positive interengagement, e.g. balls and grooves, for locking in the end positions · CPC title

• F15B15/16

  of the telescopic type · CPC title

• F15B15/1423

  Component parts; Constructional details · CPC title

• F15B15/1466 Primary

  Hollow piston sliding over a stationary rod inside the cylinder · CPC title