- Joined
- Feb 8, 2014
- Messages
- 11,145
As some of may know I'm building a small punch press for a customer. https://www.hobby-machinist.com/threads/servo-punch-press.72601/ This press is going to be out of my control and operated by unskilled or semi-skilled labor so it must be designed to be as safe as possible short of welding a large steel box around the entire unit and welding the main power switch in the Off position. In the die area there are no pinch points, completely finger safe. No reason to be poking around in there, but ya never know. It will be guarded anyway with a lexan guard. And that guard will contact a limit switch that is in the E-stop circuit and must be in place to operate the machine. Designed to not be easily defeatable.
I had to add a stiffener to the press frame to keep it squared up, and in doing so created a pinch point at the wrist pin.
Without the stiffener installed
And with the stiffener in place. The bolt head moves up & down with the ram.
No problem, just build a lexan guard to cover the pocket.
But, this guard is WRONG. Mechanically it will work fine, the lexan is well suited for this application, and is completely finger safe. The guard allows easy access for removal of the wrist pin for die maintenance. Die maintenance would be done by skilled personnel, this is not an operator function. I have a fix for the problem and will implement it as the build continues, there are two solutions that I thought of.
But I wanted to post this to see if anybody else can point out the problems (there are more than one) with this design, it took me a day to realize that it wasn't right.
Time to put on your thinking caps. Looking forward to your comments.
I had to add a stiffener to the press frame to keep it squared up, and in doing so created a pinch point at the wrist pin.
Without the stiffener installed
And with the stiffener in place. The bolt head moves up & down with the ram.
No problem, just build a lexan guard to cover the pocket.
But, this guard is WRONG. Mechanically it will work fine, the lexan is well suited for this application, and is completely finger safe. The guard allows easy access for removal of the wrist pin for die maintenance. Die maintenance would be done by skilled personnel, this is not an operator function. I have a fix for the problem and will implement it as the build continues, there are two solutions that I thought of.
But I wanted to post this to see if anybody else can point out the problems (there are more than one) with this design, it took me a day to realize that it wasn't right.
Time to put on your thinking caps. Looking forward to your comments.
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