| 摘要 |
The present invention relates to a screen lock-unlock system for automatically locking and unlocking a screen that is within a fluid channel wherein the screen is rotatable relative to the channel from closed to open. The system includes an actuator comprising a flapper and a trigger, wherein the flapper is rotatably connectable to the back of the screen. The flapper is operably connected to the trigger for moving the trigger. And, the system is further summarized, according to one aspect, as follows. It includes a lock bar wherein the lock bar is rotatably attachable to a screen support structure, the lock bar being rotatable by movement of the trigger. The lock bar intercepts the rearward arc path of a blockable part (such as a flange extending laterally from the screen). The flapper is located and oriented with respect to the closed screen for at least part of the flapper to be rotatable in response to pressure from impact fluid. The trigger is located sufficiently close to the lock bar for rotation of the trigger to move the lock bar in a direction and amount needed for at least part of the lock bar to clear the blockable part, allowing the screen to open in response to pressure against the front of the screen. The screen is rotatable toward a closed position in response to the diminishment of the pressure against the front of the screen. And, the lock bar is biased in a counter-rotation direction (by part of the lock bar and/or another biasing device) to at least help hold the lock bar in and/or return it to a locked position.
|
