Greetings to all,
I am the volunteer lighting director & special effects technical advisor for a church sponsored community theater group in eastern PA. Specifically, I have a scene (in the play Cinderella) where a set of hinged windows need to open "magically" three times. The actress can close the windows each time, but they need to reopen on their own.
I have a plan on paper, but am open to any suggestions/improvements:
I had thought about using (2) side by side windows, hinged on their sides, that open "outward"--rather than a vertically hung window. I would attach horizontally mounted springs to the windows (out of sightlines) that would provide the necessary force to pull the windows open on demand. I was considering the use of solenoids that could act as mechanised door release latches; attaching (1) solenoid to a small spring clip placed along the bottom edge of each window frame. The solenoid plunger would need to be in a "normally extended" position when no power was applied. This would keep the spring clips under no tension, thereby holding windows in a "normally closed" position. When the windows needed to "fly open", I would energize the solenoid--thereby moving the spring clips downward. The windows would now be subjected to the force of the horizontal springs, pulling the windows to open.
But I have some questions about this: Can the solenoid remain powered on for ~20 seconds--keeeping the spring clips out the windows path-thereby allowing the actress to "close" the window? Next question: when solenoid is de-energized, will the plunger automatically return to the extended position--thereby releasing tension on the spring clips--resulting in the windws being held closed?
Thanks again for your input--John A
I am the volunteer lighting director & special effects technical advisor for a church sponsored community theater group in eastern PA. Specifically, I have a scene (in the play Cinderella) where a set of hinged windows need to open "magically" three times. The actress can close the windows each time, but they need to reopen on their own.
I have a plan on paper, but am open to any suggestions/improvements:
I had thought about using (2) side by side windows, hinged on their sides, that open "outward"--rather than a vertically hung window. I would attach horizontally mounted springs to the windows (out of sightlines) that would provide the necessary force to pull the windows open on demand. I was considering the use of solenoids that could act as mechanised door release latches; attaching (1) solenoid to a small spring clip placed along the bottom edge of each window frame. The solenoid plunger would need to be in a "normally extended" position when no power was applied. This would keep the spring clips under no tension, thereby holding windows in a "normally closed" position. When the windows needed to "fly open", I would energize the solenoid--thereby moving the spring clips downward. The windows would now be subjected to the force of the horizontal springs, pulling the windows to open.
But I have some questions about this: Can the solenoid remain powered on for ~20 seconds--keeeping the spring clips out the windows path-thereby allowing the actress to "close" the window? Next question: when solenoid is de-energized, will the plunger automatically return to the extended position--thereby releasing tension on the spring clips--resulting in the windws being held closed?
Thanks again for your input--John A