Shop OBEX P1 Docs P2 Docs Learn Events
small piezoelectric buttons for a no-battery keyboard? — Parallax Forums

small piezoelectric buttons for a no-battery keyboard?

ReachReach Posts: 107
edited 2013-09-10 10:42 in General Discussion
Hi,

I am in search for small piezoelectric buttons for a IR no-battery keyboard that I am designing. Really nothing new here as these devices are currently made in TV remotes etc, I need your help in finding a source for my new invention.

I need small or better yet surface mounted packages. It seems all I am able to find are bulkhead mounted types.

Thank you,
Reach...

Comments

  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2013-09-08 10:01
    Parallax has sold a piezo-electric sensor in the past that might do. While it is a through-hole item, the tabs could be bent 90 degrees to make a keyboard configuration. I am not sure if these tabs can be cut down or ordered in smaller sizes, but at $2.50 each frop Parallax.. it may be prohibitively expensive.

    You might use a super-capacitor for storage of power generated to drive your keyboard communications and encoding. These on a separate backplane would provide the power from all the button pushing.

    http://www.parallax.com/product/605-00004
  • xanaduxanadu Posts: 3,347
    edited 2013-09-08 10:17
    You mean the "clicker" remote style buttons? Their mechanical nature and distance they need to emit, smaller may not be better. Are you talking a full size 101 key keyboard?

    I am not sure if this helps, but a piezo disc element by itself generates a small amount of voltage when tapped hard enough. I have a pile of them but they're probably too large for a keyboard. When I saw this I ordered a pile of them - http://youtu.be/Xuw9frP1GNo
  • ReachReach Posts: 107
    edited 2013-09-08 10:30
    I am specifically looking for smd piezo buttons or speakers smaller than 10 mm but I may have to settle on the 10 mm piezo speakers. Now as I type this Ill even try to use them as logic gates too :) a battery-less logic gate kind of interesting wouldn't you think? :thumb:
  • ReachReach Posts: 107
    edited 2013-09-08 10:32
    Thinking more on the uses for piezo devices - I would love to find a source for a very large piezo device as in FEET? Imagine a flag pole piezo device as it sways in the wind creating mega volts? My sailboat will be all electric someday.
  • xanaduxanadu Posts: 3,347
    edited 2013-09-08 10:40
    I don't know much about it, but in working with larger piezos I can tell that anything less than 10mm may not be able to produce a workable signal. If it did I think it would need to be spring loaded with a striker, like the ol "clicker" remotes.

    I find a battery-less very interesting, especially the stuff people are doing with peltier and energy harvesting. Crystal radio is another one of my all time favorites :) Solar not so much but hey maybe it can be a hybrid design and use more than one way to produce the power.
  • ReachReach Posts: 107
    edited 2013-09-08 14:10
    So how large are the piezo's you're working with? Im very curious to harvest energy too.

    I'm thinking that if I cant find BIG piezo's then i would sew many small ones into a fabric and hank it on my jib sail allowing it to flap freely in the wind. better yet drag it in the sea during a storm - but water penetration would be difficult to overcome cheaply.

    On the button topic the power needed could be small for my project.
  • xanaduxanadu Posts: 3,347
    edited 2013-09-10 10:42
    They are 50mm diameter with wires soldered on already. http://www.eio.com/p-33137-avx-kbs-50da-1c-piezoelectric-acoustic-generator.aspx

    They sent me a box of them 50 I think for $10 plus shipping. They seem to produce good voltage with little mechanical action, I guess due to their size. I can't even remember what I was going to try to use them for :(

    I sail too. As far as dragging stuff goes I always thought about dragging copper and aluminum conductors to produce some power but haven't tried.
Sign In or Register to comment.