Jck57's Full Auto Scanner Scheme #6

Built a scanner? Started to build a scanner? Record your progress here. Doesn't need to be a whole scanner - triggers and other parts are fine. Commercial scanners are fine too.

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jck57
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Joined: 23 Nov 2009, 15:21

Jck57's Full Auto Scanner Scheme #6

Post by jck57 »

Using the cradle from #5. Two gearmotors with long axles coming up on 45 degree angles toward each open end of the book. Sorta like the page flipper from Servo Auto Scanner:
flipper.JPG
flipper.JPG (62.48 KiB) Viewed 14158 times
But instead of a servo motor it's a gearmotor with continuous rotation at 20 RPM.

So there are two of these and one has the rubber doo-hicky that lifts the page and the opposite one has the doo-hicky that flips the lifted page. And each axle has a wedge-shaped thing that holds the border of the page down as the cameras fire. As the hold-downs rotate into position, they drop down and hold tight to the page because there is an axial cam that effectively lenghtens and shortens the axles of each motor. I couldn't find a good pic of an axial cam. Think of a cup with a wavy rim that is attached to the axle. As it rotates, the cup's edge rides on a cam follower. The axle shaft is splined to the motor shaft and can move axially. The cup's irregular shape acting on the follower will raise and lower the whole deal during the 360 degree rotation cycle.

So these two motor/axle/doo-hicky things perform all the page fipping ops. A few micro-switches and relays handle the control logic without need for a microprocessor. The page lifter doo-hickey features adjusters for page size and downforce.

What do you think?
M@rtijn
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Country: Netherlands

Re: Jck57's Full Auto Scanner Scheme #6

Post by M@rtijn »

Cool stuff!

How about making the wedge-shaped thing rotatable so it can wobble to prevent any page damages and to help the adjustable cradle a bit when pages are turned.
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jck57
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Re: Jck57's Full Auto Scanner Scheme #6

Post by jck57 »

So the wedge rotates with the axle except it can free spin a few degrees on the axle. This means that as the axle is rotating the wedge into position, the cam drops the wedge down but with the wobble on the shaft the wedge can drop straight down as the shaft still turns. And when the wedge needs to rise again, the wobble mount allows the wedge to pull out of the book gutter without rotating at the same time. The cam lifts the wedge straight out and then rotates it.

Yes. Great idea, M@rtijn.
M@rtijn
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Joined: 13 Feb 2012, 16:18
Country: Netherlands

Re: Jck57's Full Auto Scanner Scheme #6

Post by M@rtijn »

Would you consider a vacuum clamping system to hold books down on the cradle to be a workable option in the current design? With aluminum plates on the cradle wings for a clean surface, I believe only a small pump is needed for those few psi to hold a book down.

cradle.jpg
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Last edited by M@rtijn on 01 May 2013, 09:21, edited 1 time in total.
M@rtijn
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Joined: 13 Feb 2012, 16:18
Country: Netherlands

Re: Jck57's Full Auto Scanner Scheme #6

Post by M@rtijn »

The idea is to have some adhesive tape around the edges of the wing to create space between the wood and the aluminum plate. By having a hole drilled down the middle of the cradle wing for a valve and tube, it can than be connected to a small pump.
cradle.jpg
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jck57
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Re: Jck57's Full Auto Scanner Scheme #6

Post by jck57 »

That should work. You could make the hole pattern to match the smallest book and it would still work for the largest without any leakage.
M@rtijn
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Joined: 13 Feb 2012, 16:18
Country: Netherlands

Re: Jck57's Full Auto Scanner Scheme #6

Post by M@rtijn »

This pattern I believe has good airflow for small and large books.
grid.jpg
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Last edited by M@rtijn on 04 May 2013, 09:27, edited 5 times in total.
dtic
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Re: Jck57's Full Auto Scanner Scheme #6

Post by dtic »

As an alternative to vaccuum clamping check if regular anti-slip material is good enough, e.g. http://www.ikea.com/us/en/catalog/products/60098895/ .
M@rtijn
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Joined: 13 Feb 2012, 16:18
Country: Netherlands

Re: Jck57's Full Auto Scanner Scheme #6

Post by M@rtijn »

A setup similar to a laptop cooler with a heavy fan or a small handheld vacuum cleaner motor beneath each cradle wing would be an idea.
setup.jpg
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jck57
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Re: Jck57's Full Auto Scanner Scheme #6

Post by jck57 »

Interesting work, M@rtijn.

I've put together an axial cam prototype. Video here: http://www.youtube.com/watch?v=7hm8J2Dv7bI
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