초록 ▼

A method and apparatus for operating a fluid actuated actuator between one and another alternate positions provides different forces for locking and unlocking the actuator. The actuator may use the same fluid pressure to operate a primary piston within a cylinder and to operate the locking mechanism

A method and apparatus for operating a fluid actuated actuator between one and another alternate positions provides different forces for locking and unlocking the actuator. The actuator may use the same fluid pressure to operate a primary piston within a cylinder and to operate the locking mechanism. Actuator fluid is communicated to unlock the lock member and to move the piston back to its open or unactuated position. A sequencing valve determines the proper sequence of actuating the primary piston before the locking mechanism is driven in place, and clearing the locking mechanism prior to reciprocating the piston back to its unactuated position. Different forces for locking and unlocking the locking mechanism is provided by a free-floating piston mounted on a guide rod. The invention may also be applied to a BOP or the like where different opening and closing forces are desired.

대표청구항 ▼

[ I claim:] [1.] A fluid actuator comprising:a. an actuator body defining an actuator cylinder having opposing ends;b. a piston in the actuator cylinder, the piston positionable between alternate positions within the actuator cylinder;c. a rod on the piston extending through one end of the cylinder

[ I claim:] [1.] A fluid actuator comprising:a. an actuator body defining an actuator cylinder having opposing ends;b. a piston in the actuator cylinder, the piston positionable between alternate positions within the actuator cylinder;c. a rod on the piston extending through one end of the cylinder for connection with a part to be moved, and a tail rod on the piston having an outer end extending through the opposite end of the cylinder;d. a lock member coupled to the actuator body, the lock member comprising:i. a lock member body;ii. a locking mechanism in the lock member body, the locking mechanism having a wedge reciprocable between a first position in which the wedge is disposed to one side of the tail rod, wherein the piston is moved to one of its alternate positions, and a second position in which the wedge is disposed across the outer end of the tail rod, as the piston is moved toward its other alternate position,iii. means for communicating actuating fluid to the cylinder and to the locking mechanism which maintains the wedge and the tail rod outer end in locking relation as the piston moves to and is in the other alternate position;iv. means including passage means and normally closed valve means therein for controlling communication of actuation fluid to the cylinder for moving the piston to the one alternate position;v. means for communicating actuating fluid to the locking mechanism for moving the lock member to the first position;vi. means operable by the locking mechanism wherein it is moved to the first position to open the valve means and communicate actuating fluid to the cylinder to move the piston to the one alternate position; andvii. a floating piston in the lock member body, wherein the floating piston disengages the wedge in one direction of travel, in order to reduce the effective working area of the floating piston, but engages the wedge in the opposite direction of travel in order to increase the effective area exposed to the hydraulic pressure for movement of the wedge.