Problem: Pushing the Button
What will the cylinder do if the push button is pushed and held?
What will the cylinder do if the push button is pushed and released with a 50-psi load on the cylinder?
Find Out the Solution
The cylinder will extend, dwell, and then retract after a period of time for both answers.
The operator will push the left valve directing air to the shuttle valve and to the pilot-operated air valve. When the valve shifts, it directs air to the cylinder and also to both pilot lines. Air will go to the left pilot line, through the shuttle valve, and hold the main valve energized after the operator lets go of the push-button valve. Air also goes to the right pilot line, through the flow control, and fills the air tank. When the pressure gets close to the system pressure on the right end pilot, the spring will take over, pushing the valve to the left and retracting the cylinder.
This is a one-shot circuit. It does not matter if the operator just pushes the button momentary or holds the button; the cylinder will respond the same.
Deadline past. Not available for submissions.
By Ernie Parker, AI, AJPP, AJPPCC, S, MT, MM, MIH, MIP, MMH,
Fluid Power Instructor, Hennepin Technical College, EParker@Hennepintech.edu
This teaser is printed in the Fluid Power Journal. Those who submit the correct answer before the deadline will have their names printed in the Society Page newsletter and in Fluid Power Journal. The winners will also be entered into a drawing for a special gift.
