How do store security devices work?

February 12, 2005 2:26 AM

BlockbusterPseudoTheftFilter: OK, not really stealing, just curious. I rented a DVD from Blockbuster the other day only to find (on returning home) that the clerk had not removed the yellow security tab. On calling the store, I was given the go-ahead to cut the box apart so I could watch the movie without making the trek back. It was easy enough to cut it open from the other side, but it's made me really curious about that security tab, which I thought would come apart much more easily. Which brings me to the question, which has been brewing in the back of my head forever ... does anyone know how these things work, exactly? The best I've been able to discern so far is that magnets are involved.
posted by Sinner to science & nature (8 comments total)

Having worked at a Blockbuster some years ago, I can tell you that each store has 2 or 3 openers for the dvd's drilled into the counters. From what I remember, you place it in the holder, hold the dvd with one hand and the lock with the other and pull.

Lucky for me, before I left, I took one of these openers home with me so I didn't ever have to return to the store. If you get lucky, they leave them lying around in the back room, along with all sorts of other goodies.

Not that I permit stealing or anything...

Do it
posted by Derek at 3:51 AM on February 12, 2005

There are a few different methods. I read this explanation (with more detail here) a few weeks or months ago which seemed pretty thorough.
posted by cardboard at 4:04 AM on February 12, 2005

cardboard-- the post isn't about the anti-theft device you cite, but rather the anti-theft device that (unless removed) makes it difficult to open a Blockbuster DVD case.

Derek-- can you describe, erm, how it works?
posted by trharlan at 8:09 AM on February 12, 2005

I had the same problem a few months back. The person at Blockbuster forgot to remove the yellow tab when rented our movie. I was afraid that I wasn't going to be able to watch the League of Extraordinary Gentleman. Thankfully I had a screwdriver and ten minutes to spare. After some poking and prodding, Sean Connery awfulness ensued.

I can't tell you how it works, except that there's a few magnets you have to pull out of place and the yellow strip pulls right out.
posted by Arch Stanton at 8:31 AM on February 12, 2005

trharlan : Thanks for covering for me on the clarification front. I'm still hopeful that Derek can provide more of an explanation or that someone else might have a link.

cardboard: Thanks, but as trharlan said, I have a rough understanding of how the kind of anti-theft mechanism mentioned in your link works, but I'm asking about the yellow plastic strips that run (internally) along the spine of the DVD case.

Unfortunately, I still don't really get it beyond knowing, as Arch Stanton echoed, that magnets are involved. I have a pretty powerful magnet that I keep lying around for no good reason, and running it along the spine of the case, it encounters at least two magnets, but I can't figure out how they conspire to lock the strip into place. I don't want to completely tear the case apart to figure it out (although it's already split open from the other side courtesy of a large steak knife).
posted by Sinner at 11:13 AM on February 12, 2005

OK, I had a little more time to look (and help from a friend) and while I'd still like a detailed explanation, I can provide more information. First, this picture shows what what the case looks like when opened with lock still inserted.

It appears that at least one manufacturer of this type of locks (if not the only one) is a company called Clear-Vu. The product they use is the reusable Clear-Vu Zenith-Pac (or a reasonable facsimile thereof), although Clear-Vu also makes a Clear-VU One-Time pack and several others. Apparently, the lock comes separately (as does the unlocking mechanism).

Follow this link to QT animations of the reusable lock and the one-time lock.

Having gathered all this information, I'm still curious as to exactly how this product actually works. "Magnets" isn't quite sufficient.
posted by Sinner at 11:54 AM on February 12, 2005

As far as I could ever tell, the magnet from the base unit reversed the polarity of the two magnets creating the lock. Making it so that you could pull the lock from the case.

After looking at the picture you provided, these are different from the cases we used to use with the locks being encased in another sheeth of plastic. Now that the lock (yellow part) is inside the actual case, this may have another locking mechanism that still involves magnets.

I'll talk to my undercover resources and find out more.

Derek - Over and Out
posted by Derek at 8:11 PM on February 12, 2005

There are magnets at the end of a hinged lever. When not in the unlocking device the hinged lever rests in a pocket of the case. While in that pocket the security strip can not be pulled out, similar to opening a door without turning the nob. Placing the case in the unlocking device aligns magnets on the opposite side of the pocket drawing the magnet out of the pocket along with the hinged lever lock.
posted by darkmatter at 3:18 PM on February 13, 2005