Jck57's Full Auto Scanner Scheme #6

[M@rtijn]

Does the cam in the current design has to have a small variable offset that can self adjust, so it can accommodate for the changing drop depth of the wedge needed in varying book thickness? Or is something already pushing the wedge down?

I am having difficulty visualizing the workings of the idea. I probably need to see it actuality work.

Some ideas for offset on the disk cam.







A roller guide on each cam would be a nice feature for easy rotations.

[M@rtijn]

An excellent design, I can now see the workings of the idea. Would you care to build a demo so to see if any fine-tuning is needed?
Actually a lightweight construction can be made, it just needs little support. I will contemplate over this a idea and post it later on.

[dbmoura]

I've made a quick version with rollers. Is it your idea M@rtijn?
The fine-tunings could be made by drawing over or directly in the model. As the full mechanism is not in place, the adjustments of pieces, like the extension of the axe, is uncertain for me at this moment.
Jck57 should have some drawings or models of the cradle he made. I saw the videos in the Youtube but is there detais of measurements used. I am thinking that this would be the starting idea of this building.

[M@rtijn]

Great 3d skills dbmoura and yes these are the rollers I mean. Indeed it's better to do fine-tuning in a 3d drawing first.

I made a concept with a different pivot and a base that can either stand vertical or attached horizontally to the cradle platform.

In the horizontal orientation, the follower is to be attached along the base, but than it needs to be extending over to align it with the cam.

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[jck57]

Beautiful work dbmoura. Yes, I agree the cam followers must be ball bearings. Started fabricating the working prototype, steel Wedge made adjustable for experimenting. Thanks, guys.

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[jck57]

Cradle drawing made with instruments:

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We need the working faces of the cam and follower to be parallel with the radius line of the pivot:

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[jck57]

Another way is to use a disc cam and a longer roller on the cam follower. The working surface of the cam could be contoured to squarely meet the follower during 360 degrees of rotation. Going out of town for five days starting Wednesday so I'm trying to get more stuff up on here for M@rtijn and dbmoura to play with.

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[dbmoura]

I've made smaller cams put the rollers but for future test I am building models that we could see in movement. For that I'll use Inventor Fusion (free for mac, at least for while)

[M@rtijn]

New setup with a gear/slider mechanism (mangle drive) as a wedge.

The rotational motion is transformed in rectilinear motion with quick return.

The concept of the self-centering clamps can also be applied to the wedge stands.

The gear and frame should be height adjustable on the stand, similar to a vernier caliper.

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[jck57]

dbmoura: I'm excited about the possibility of kinematic modeling for this project.

M@rtijn: Interesting gear mechanism. I'm already with you on the self-centering stands. Just planned on getting to that later. With the present cradle design, the wedges should be able to stay at about the same height for various books.

Next come the cams and followers. Hope to get some shop time tomorrow.

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