Re: INDEXER ?

"Arne Chr.Jorgensen" wrote:

> From: "Arne Chr.Jorgensen" <instel@...>
>
> Hi all,
>
> A lot of interesting stuff here, - but then I start to wonder a
> bit. I may have some wrong idea of what an indexer is all about ?
>
> 1. Would anyone care to enlighten me ? ( more down to bits and
> pieces )

There are two things related to machines called indexers. One is a
device, usually connected to a stepper driver, that makes the stepper
step through so many steps when given one pulse. Modern ones do
accel/decel on those steps, as well. This is an electronics-only box.

The other thing is more completely described as an indexing head.
As used with a general, 3-axis CNC machine, it looks kind of like
a dividing head (which has a crank on the side, and each revolution
of the crank turns a lathe chuck so many degrees (often 9 degrees)).
Instead of the crank, there is a button which can be pressed by a
tool in the spindle of the CNC, and it advances the lathe chuck by
a predetermined angle.

Other, somewhat similar devices are CNC-modified dividing heads
(I have the dividing head, when EMC gets the 4th axis support, I
will CNC it). There are also commercial rotary indexers, usually
completely separate from the machine tool. We have a couple of
Yuasa indexers at work, they look like a CNC'd rotary table.

>
> 2. How do you sync steps with this ?

Not sure exactly what you are asking, here, partly because I
don't know which of the above things that are all called indexers
you are talking about.

Jon