Electro-mecahnical locks used in a turnstile

[bobdxcool]

I was looking to build a RFID operated turnstile similar to picture below. I will have RFID readers on both ends where the door would open from either end only if the RFID is authenticated on either end. I was wondering what are the type of locks used in these turnstiles which open the turnstiles when an RFID authenticated and then lock these turnstiles and prevent them from moving after a person enters through the turnstile after successful authentication. Are these special locks or some kind of electromagnetic locks ?

 

[MikeHalloran]

I'd bet you can buy the turnstile assembly for less than the cost of developing it.

Mike Halloran
Pembroke Pines, FL, USA

 

[bobdxcool]

@Mike It's not about the cost. I have different plans when compared to build plan compared to your regular ones. So, I wanted to know what kind of locks are used to startoff with.

 

[itsmoked]

The lock would normally NOT be something you buy off-the-shelf it would simply be a solenoid that pulls a pin out of a toothed disk. The pin is spring applied and solenoid removed. Once the solenoid is activated the turnstile can start turning and the solenoid doesn't need to be energized because the pin now rides on the disk until it comes to the first index hole and drops in by spring force. The pin holes are located such that the person can easily fit thru between single indexing points. In the picture shown there would be three index points.

Another method that is 'analog' instead of the rather 'digital' method just described is to use a standard electrical brake that is, again, spring applied and electrically released. The the turnstile shaft runs thru the center of the brake.

How will you deal with the RFID carrier standing next to the turn style and letting it run for 37 people?

Best would be the indexed method and only one cycle per minute or something like that.


Keith Cress
kcress -

http://www.flaminsystems.com

 

[Compositepro]

If a lock has to be operated electrically, of course it will be an electromagnetically operated lock. I think you should devote a little bit more thought to your questions before you ask.

 

[IRstuff]

You may need to reconsider forcing the RFID for both directions. This is typically a bad idea for buildings, since it means that in an emergency, the people are trapped behind what is essentially a locked door. Be ready to sued out of existence if that ever happens. The ones that I've used are only locked in the inward direction. However, there may still be a rationale for having a reader for the entering direction, simply to keep track of people and for forensic examination in case of issues.

The logic to prevent multiple activations is pretty straightforward. Once someone goes through the gate, there's no plausible way for that person to be waiting to go through from the same side again, so that particular RFID can be disabled for at least a minute, unless an entrance reader detects the RIF re-entering a gate.

TTFN
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