# Stuck on axial cam, to rotate and reciprocate cylinder.

1. Nov 1, 2013

### revive

Hello,
Although I've been reading and gleaning from the forum for a while, this is my first post. Thanks for reading!

I'm trying to automate a manual process process. The concept is simple enough, but I need some expert input on how to accomplish it with the least amount of components.

Here is what we're trying to accomplish:
we have a cylinder (max 0.75 in diameter) that we need to rotate (90 degrees) AND drive back (.0500 inch) against a drive spring.. at 90 degrees the cylinder needs to drive forward, over-traveling 0.250 inch (a total linear motion of 0.750 inch). The cylinder will have a hardened steel 'punch' attached that needs to impact a plate at approx. 100 ounce/inches. All this needs to be actuated by a single movement of a lever. Upon returning the lever to its start position, the cylinder needs to be ready to complete another punch cycle.. with a max of about 120 cycles per minute.

My initial thought (for which I've attached an incomplete drawing of) was to have the lever act upon an axial cam running around the diameter of the cylinder. That will turn the cylinder providing the rotation and at the front of the cylinder we can utilize 'lobes' that will drive the cylinder rearward (providing the linear action) against the drive spring. The main aspects I can't resolve are:

1) controlling the forward, over-travel motion of the cylinder and
2) when the lever moves to it's forward starting position, we need to make sure that the axial cams are aligned to allow the lever to rotate it again. And the cylinder cannot be allowed to freely rotate or lose orientation to the pin holes.

The only way I can think of to do that, is to have to lever initially rotate the cylinder a portion of the 90 degress as it returns to it's start position, then as the lever travels rearward rotating the cylinder, it only has to complete the 90 degree movement... So, once the cylinder drives forward, and the lever moves forward to rest, that last forward movement of the lever will have slightly rotated the cylinder to align the next axial cam for the levers bearing..

Any help is greatly appreciated and I am open to any ideas on how to complete this.

Here is a link to the rough drawing I've created:
https://www.dropbox.com/s/rwybduokzr4ovba/punch-cylinder.jpg

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