Solenoids and actuator confusion

Technical Pneumatics
1

Ive been experimenting with pneumatics lately. When a solenoid valve opens, does it have a specific time to open and it automatically closes, or do you need to pull a trigger to open and another trigger to close it? Just the output of the solenoid from the stored air.

And is it possible to connect two solenoids to the input of one actuator? For example a 40psi solenoid and a 60 psi solenoid to one cylinder and have both open at the same time.

Kevin

2

The solenoids must be ordered to open and close by your code. They are not momentary, and they will only open and close by your software command. There is one exception and that is a single solenoid will automatically return to it’s home position when your robot is disabled (a double solenoid will not).

  • You can write code that, on a single button push, opens a solenoid for a set time, then closes it again automatically.
  • You can code a solenoid to only be open while you push & hold a button.
  • You can code a solenoid to reverse position with every push of a button.
    *]You can set one button to open and a different button to close.
    You can connect the pneumatic tubing from two different solenoids to a single cylinder. Usually not two different pressures opened at the same time however.
3

There are two types of solenoids: single-coil and double-coil. You can tell the difference by looking at the number of wires; single coils have one pair of wires, double coils have two pairs of wires.

Single-coil:
as long as the red wire is recieving power (cRio output is on), the cylinder is in one position. As long as it isnt recieving power, the cylinder is in the other position. If you have it mapped to a trigger, then you must hold the trigger for as long as you want it in one position, then when you release it it will go to the other position

Double-coil:
When one pair recieves power (turned on by the cRio), the cyllinder moves to a position and stays there until power is applied to the other pair. As soon as it switches, you can remove power and it will stay there. In this case, you would have one button to go to position A and another to go to position B. Don’t press both at the same time, it is impossible to tell what will happen (it will go to a random position).

Having a 40psi and 60psi solenoid on one cylinder will not help. It is probably not a good idea. The opposite, two cylinders to one solenoid, is quite common, for applications where an apparatus has two symmetrical cylinders, such as two transmissions (left and right) or a large device that needs a cylinder on each side.

4

That explains alot. :slight_smile:
Thanks for your help.