Chuck Safety

So are you using an inductive prox? If so, what if a chip gets in there?

Hell of a lot nicer than those spring loaded chuck keys. Yuck.

Wes

-- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller

The bottom has slots in it to help with chips,doubt if they will.

They machine a lot of plastics and composites so wasn't much of a concern.

They used spring loaded ones but the guys were complaining about them. Dave B

Just put in series with the foot pedal for the break.

Dave

Good. As soon as one fits something to do the thinking, I think a lawyer is born.

No kidding. They put spring loaded ones out in the tool room. I made my own chuck keys the next night.

Wes

There is a simpler solution.

I left the key in a chuck in High School shop class (took something out of the chuck, and walked away with the key in the chuck). I got my butt paddled. Never did it again.

I try to keep the key glued to my hand but a holder and prox beats that spring thing.

To the op, having logic that requires a key raise before every start would prove the key was in the holder instead of chips. There are very small PLC's that can provide this function. If it wasn't late I'd likely come up with a relay based solution. I'm off to bed now.

Wes

-- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller

On Thu, 20 Nov 2008 13:26:00 -0800, the infamous Dave B scrawled the following:

Good idea.

So, who golfs? Is that Aridzona?

-- Laziness is nothing more than the habit of resting before you get tired. -- Jules Renard

That's a very neat arrangement. I saw an idea years ago to hang the key on a lever type microswitch connected to open the power leads if the key was not present. Your idea would be more foolproof.

Don Young

Never underestimate fools. I see irritated users just dropping a big drill bit or boring bar in there to eliminate the hassles.

Try something better to detect when the chuck key is in the vicinity of the chuck, not when it's in a specific holder. if the chucks aren't changed often, I can see an arc of hall effect sensors positioned around the chuck to detect a magnet epoxied on the chuck key. Detect when the chuck key is in the chuck to disable, as long as it's not in the chuck let 'er rip. Why would one care if the operator puts the chuck key on the tool cart, in their back pocket, etc.

Even simpler would be a curved piece of plexiglass as a flip down shield over the chuck, with a switch to detect when it's down. Flip the shield up and do your thing with the chuck key, when you take the key out flip the shield back. If the key is in the chuck, the shield can't come down and the lathe can't start. Flipping the shield down as you take the chuck key out takes less time and effort than inserting the chuck key into a little tube much further away.

Las Vegas

The only thing stopping them in this place is they will be fired on the spot.

Howeve,r I like the idea and Thanks

Remember -- they keep making better idiots. :-)

Enjoy, DoN.

I am not sure why the need for so much engineering here. They sell lathe chuck keys with built in springs, so that you need to push it into the chuck and it falls out as soon as pressure is released. McMaster has plenty of them.

Interesting. I've got a spring loaded one for my 3-jaw chuck, and it still is spring loaded. I'd much rather have it there than to work without it -- and I *trust* myself to remove the key. :-)

Enjoy, DoN.

No kidding...............howbout because they suck?

They are different lengths and are color coded. The switches adjusted to each one.

They never change chucks as they are dedicated machines.

This was just a simple solution and beats what they had (spring loaded keys)

Thanks for the comments

Dave B

Seems like the idea is to prevent errors, not intentional stupidity. I presume the operator has a vested interest in not starting the lathe with a chuck key still in it, and if there is a good, safe, convenient place to put it that both allows it to start the lathe and keeps it in one place so you can find it right away the next time, why would an operator not put it there? Seems like defeating the purpose of the sensor could easily be made grounds for termination, and problem solved. The sensor eliminates mistakes, the rules kick out the malicious.

Looks like a very practical solution. Seems that is the hardest thing to get my students to do, is not leave the chuck wrench in the spindle.