A Cd Question

Hi! I hope everyone is staying safe and warm!

I have a question about CD drives. My question is : I thought that CD drives used a set of magnets to spin the CD (or DVDs even). Is this true? Or do they now have some sort of direct drive?

Thanks in advance!

Mark

 

https://electronics.howstuffworks.com/cd.htm
a motor; that's why optical drives need a power source.

 

Thanks plodr. I read that article a day or so ago. My problem was that I read (years and years ago) that the CD drive used tiny magnets to spin the motor. This goes back to the "No moving parts" things they used to talk about with CD drives. So it is my guess that CD drives changed to a direct drive center motor. However, both CD and DVD drives will still spin for a few seconds after they turn off. Still thinking about this but thanks for the reply.

 

Magnets inside a computer, near a spinning hard drive? I doubt that!

We used to erase things using magnets.

 

Read this.
https://en.m.wikipedia.org/wiki/Optical_disc_drive

The magnets (permanent or electro) are inside the motor. That's how DC motors work.

 

@plodr - It depends upon the strength of the magnets. Super-duper-yanks your teeth out - no. Magnets like those used on phone covers - yeah, I can see it.

@Eldon - off to read.

Just read this from Eldon's info: "Half height drives fasten the disc using 2 spindles containing a magnet each, one under and one above the disc tray."

 

Also : "In the third photo, the components under the cover of the lens mechanism are visible. The two permanent magnets on either side of the lens holder as well as the coils that move the lens can be seen. This allows the lens to be moved up, down, forwards, and backwards to stabilize the focus of the beam."

And : "After the disc tray stops moving inward, as the motor and its attached parts rise, a magnet near the top of the rotating assembly contacts and strongly attracts the clamp to hold and center the disc."

I think this Wikipedia write-up asnwers my questions. Thanks to both plodr and Eldon.