Quote:
Originally Posted by Peter Matteson
Not true. Just be more creative and you'll figure it out.
|
I can think of being able to evacuate with a partial throw and continue to slightly move the piston as one way.
Another way is when the end of the stroke is reached, switch the vacuum side of the piston to atmospheric pressure (solenoid with other outlet blocked) and move piston to starting position, swithc to open to the suction device again and then continue to evacuate.
Or the third is to run two connected pistons driven by a crank shaft with switching between the two vacuum chambers via solenoid.
The third is the most complex and closest to a continous vacuum. The second you have to stop for a bit to move and the first you still are stuck at the end of the throw.
edit: actually a single piston would work for the third. Just use a solenoid to switch because either way you pull/push the piston you will get a vacuum. Still this isn't continous because of the stops at the ends of motion. Also without care the switching may introduce enough atmospheric air to break the seal.