Variable Speed Chain Drive

I'm quite sure what you actualy found was a "Variable Speed Chain Drive" of sorts. Why not send the literature that you are refering to?

Hi Tim, Here is the picture courtesy of the link.

www.made-in-china.com/showroom/qjchain/product-detailiMKnJxdwbEkq/China-Roller-Type-Infinitely-Variable-Speed-Chains.html

Tony

Then the first two links by first Guest should help you understand.

Put that chain into a gearbox with variable pulleys that open/close due to centrifugal force (just like the animated gif on the "how stuff works" page with substituting the belt for the chain)

The picture was worth a thousand words Tony, however before my first cup of coffee I see your question has been answered.

Id rather control speed some other way.

transfer power via a centrifugal clutch to a suitable sprocket and `viola

This chain is made for stepless variable speed driver.

http://www.zjhql.com/product_show.asp?id=12

this is the manufacture address, you can see more specification on the page and how to connect them.

they also produce silence chain and etc.

It is called PIV drive which provides posative variable speed drive and should be available with your local gear box dealer. Now a days people use VFD drive,variable frequency drive, which is electronic drive and does not need mechanical hardware. These are mfd. by Siemens and others.

Sure this is known as PIV (Positive Infinitely Variable) Gear box.

The principle is that you have a fixed length of chain running between two cone pulleys operating at fixed centres. One of the cone pulley is spring loaded and other can be opened and closed manually to achieve desired ratio of out put. It is like having a stepless combination of drive and driven pulleys. For a given input rpm, you can either reduce the output rpm or increase it to suitable requirement in the given range. A word of caution, remember to change the speed ratios only when the gear box is running as when you manually open or close one set of cones, the other, which is spring loaded one, accomodates itself to a different diameter due to fixed chain length.

I had no time to go through the links provided by other gentlemen. You may find a better explaination there.