Help finding a "small" linear actuator???

I'm wondering if anybody could tell me where I could find a "small" linear actuator. So far all the ones I have found are either scaled
down versions similar to heavy-duty industrial type actuators, which are too big for my application, or super small nano positioning actuators such as piezo actuators or the "smoovy" (http://www.mpsag.com ) or the "squiggle" (http://www.newscaletech.com/squiggle.htm ), which are too small and too slow.
I would like to find something in the middle. I'm looking for something that runs on 12V DC (or less) and has at least roughly 25mm travel, 25 mm/s speed, and at least 1-2 pounds max force. Something approximately pen size would be great, but I'm guessing it would have to be a little bigger. The smaller, the better though.
So far the smallest one I've found which has the required power, travel, and speed is about 170 mm in length, and 27 mm in diameter. (http://www.physikinstrumente.de/pdf/M235_Datasheet.pdf ). This one has a little more than I need but I'd gladly give that up for smaller size.
If anybody could point me in the right direction your help would be greatly appreciated. Thanks, Jason
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jpoge66 wrote:

Have you looked at stepper motor lead screw actuators? http://www.motionshop.com/pr/HSI-Size-11-LinAct.shtml
--
John Popelish

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Dear jpoge66:

If you don't need much in the way of positioning, except at two extremes, a solenoid would be just the ticket.
David A. Smith
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Check out the motor in the new remote control cars that are about an inch long.
The motor is supposed to be about 1/4 inch od.
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Model airplane servos and some leverage?
MG
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Does anyone think there's actually a market for such as this? If so, who'd buy it? What kind of precision would be required by the typical buyer? I'm not talking about hobbyists -- maybe the pharmaceutical industry, nuclear industry or microelectronics industry. And obviously with the latter the precision would have to be outrageous. I'd design one and sell it, perhaps, using "hobby servos" to drive it -- but probably not at the precision required for microelectronics. I've already been closely involved in designing larger actuators, timing belt driven, in various combinations and with specialized end-effectors for XYZ transfer of fairly weighty equipment over distances up to several yards. Some of what we found for use (like linear bearings) was so small it was useless to us, but could be useful for this type of stuff perhaps.
Mark 'Sporky' Stapleton Watermark Design, LLC http://www.h2omarkdesign.com
jpoge66 wrote:

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The medical electronics industry does a lot of fluid handling on a small scale. There's a potentially huge market for 'syringe drives', of 60mm stroke or so.
Several manufacturers have attempted to crack it, but it's a tough market, for some odd reasons.
In some applications, the motion has to be ultra- smooth, because the motor drives a syringe that pushes fluid through a very small pipe, and the area ratio between the syringe and the pipe amplifies position errors and mechanical noise.
You always wind up trying to sell to electronics engineers, who think that a hole punched in a sheet of aluminum is a perfectly good bearing, and can't understand why everything except electronics costs actual money.
Or, worse, the electronics engineers are busy, and you talk to the 'mechanical designers', who are really drafters and not very good ones, and are even more clueless about mechanical stuff because they don't realize the depth of their ignorance.
And you're always competing with the inside guys who will buy one of your products and knock off a cheap copy, with just the features they need for one application.
-Mike-
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Mike Halloran wrote:
-- snip --

Which is, of course, what an "inside guy" is supposed to do in a high-volume environment -- why pay _me_ tons of money for features you don't need when _you_ can spend pounds of money copying the the design features that are essential for you?
--

Tim Wescott
Wescott Design Services
  Click to see the full signature.
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Interesting reply, Mike, and your comments about selling to small-minded myopics parallel my own experiences in some ways. Certainly I can imagine the accuracy problem with such as "syringe drives", but I rather don't think I'd be as interested in driving syringes as I would be in positioning them (or something else) on small scales. Small scale programmable XYZ positioning robots, basically. If Jason's experience accurately reflects a very limited market availability of small positioning linear actuators then perhaps there might be a market there. Maybe (!) I'm just hoping someone can suggest such a niche. One niche leads to another (sometimes). Say, wasn't there a song with lyrics like that?
Regards, Mark
Mike Halloran wrote:

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www.merkle-korff.com

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How about a voice coil (similar to solenoid) http://www.beikimco.com/products/vca.php

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Check out http://www.hsi-inc.com /
They build them all to order with whatever thrust/travel you need.
snipped-for-privacy@hotmail.com (jpoge66) wrote in message

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On 19 May 2004 14:39:31 -0700, snipped-for-privacy@hotmail.com (jpoge66) wrote:

Try pneumatic actuators such as those Manufactured by Festo.
JPG
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www.edmundoptics.com p/n R56-539 28mm range, 25mm diameter, 93mm long

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