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note I know essentially nothing about solenoids

I brought this solenoid thinking that I could use it to hit an object, but when I put it to a power supply, the only direction that it would go is down. I tried changing the direction of the current but that did nothing. Is there anyway I could get the solenoid to push out instead of pull in?

enter image description here

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  1. No.
  2. Yes.

    :-).

The solenoid will "insist on pulling in" as it is built.
There are solenoids which can be made to repell the armature from the core, but they need permanent(usually) magnets in the core to work.

BUT

You can get essentially the same result by adding a non ferrous* extension to the core so that when it travels inwards the extension moves outwards.

See diagrams below:

Diagrammatic -

enter image description here

As typically implemented:

enter image description here

The above images are from this page.

If the coil end at the "pushing" end is open it will be relatively easy to insert something which can b pushed. If it is closed you may or may not be able to add a hole. Be careful not to drill through coild or wiring.


Many images from Google - most will be push solendoids - each is hot linked to a webpage.


Many for sale - some of these may LOOK like genuine push type but it is almost 100% certain that they will be pull type with an extension.


Dismantled:

enter image description here

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  • \$\begingroup\$ A side question, could you replace the plunger with a permanent magnet so that you could get both both push and pull simply by reversing the current? \$\endgroup\$ – Faken Feb 27 '12 at 21:16
  • \$\begingroup\$ @Faken - Better to make that a separate question, not a comment thread. \$\endgroup\$ – Kevin Vermeer Feb 27 '12 at 21:27
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I know this is an old thread, but If you don't want to buy a new solenoid, you have a couple of things you can do.

  1. Add an attachment like the one in the following pic:

    diagram

    Note: The object being pushed will be on the other side of the thrust pin.

  2. You can just keep current going through the solenoid (only if it's rated continuous) and remove the current when you want to push.

    I think you can use an NPN transistor to do that.

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you can replace the plunger with a permanent magnet and by reversing the current you could get both push and pull action.

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  • 1
    \$\begingroup\$ What sort of relationship would there be between applied current, position, and force? I would think that force would be greatest near the "start" position and fall off as the solenoid moved (the opposite of normal solenoid behavior) but I don't really know. \$\endgroup\$ – supercat Nov 4 '14 at 21:16

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