Holding Vacuum during air dump

Hello,

If you need to dump the air to allow someone to enter the cell, how do you handle situations where the vacuum is still holding something up and you need air to prevent it from dropping the part?

I was thinking you could have two air dumps and only drop one during normal entrance.


Thanks in advance?

That sounds plausible. We have palletizing cells with a pump generatng the vacuum. The vacuum pump continues to run upon entry while all motion is disabled. Definitely have a risk analysis done by a quaified party.

For planned controlled entry, the empty pick head goes to a park position. Sometimes when things go awry, the head could be stopped with a pallet board or cases hanging. After 15 minutes the pump shuts off and the load drops.

Just mentioning that to say know your system. We weren't made aware of that when the cells were installed and the first board drop was a surprise.

In concert with the air you can and install a physical blocking device that you can deploy to lock the load in place.

Nova5 said:

In concert with the air you can and install a physical blocking device that you can deploy to lock the load in place.

Click to expand...

I'm talking more about vacuum like the air ejectors, where if no air is flowing, it loses vacuum immediately.

Thanks for the comments.

First and foremost, do a risk assessment, then design your safety system around that.

Timeismoney08 said:

I'm talking more about vacuum like the air ejectors, where if no air is flowing, it loses vacuum immediately.

Thanks for the comments.

Click to expand...

A single point of control for a load held UP is a bad idea. If you have a failure and someone is under it.. that someone will get hurt. I am suggesting add a secondary along with solving your air control issue.

Timeismoney08 said:

I'm talking more about vacuum like the air ejectors, where if no air is flowing, it loses vacuum immediately...

Click to expand...

I may be incorrect, but are you referring to venturi effected vacuum pressure (positive air pressure restricted to create negative air pressure)?

If the positive air pressure is lost to venturi units, where a Risk Assessment deems it necessary to maintain the vacuum pressure, then there should be a safety check valve fitted or built-in to the venturi units.

If it is venturi, then one example check valve I've used before is the piSECURE check valve from piab. Have a look here and click on the Youtube video link down the page for a quick demo where they remove the inlet pressure tube and the check valve maintains the vacuum pressure...

https://www.piab.com/en-US/news/product-news/pisecure-creates-safe-vacuum-in-case-of-system-failure/

Regards,
George

Thanks GeoSpark... Great alternative to what we do at our site - plumb an unswitched manifold into cells that require retained parts during a guard door opening.
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