push pull type solenoid valve

[RobertHasty]

Hello,

Does anybody know what does this term mean? by looking at a photo, It should be a spring centered, solenoid operated DCV with manual actuation. But what does this term push pull type solenoid valve mean?

 

[Oldhydroman]

Hi Robert

Can't see any photo, but a push-pull type solenoid valve has both coils on the same end of the spool. There is a common armature which is spring centered to sit between the two coils. When you energise the coil furthest from the spool the armature (which is connected to the spool) is pulled away from the valve body. When you energise the coil closest to the spool the armature (and spool) is pushed towards the valve body. See attached file.

By adding some "steering" diodes you can make the select which coil energises by changing the polarity of the enrgisation supply. Sometimes both coils are built into the one housing.

If you do have a manual actuation it will be a type that you have to PULL to attain one switched position and PUSH to get the other switched position.

There is also a type of solenoid used in some high response proportional valve where the armature is a magnet and sits inside a single coil. When you energise the coil one way it attracts the magnet, when you energise the coil the other way it repells the magnet. I suppose you could describe this as a push-pull solenoid as well.

DOL

 

[RobertHasty]

Hello,

Thanks for answer and for great attachment.

I didn't put picture anywhere. The valve that I'm talking about can be seen here. There' s a datasheet for download. By Your description and photo, I think that is what it means.