Re: [CAD_CAM_EDM_DRO] Linear vs. Rotary Enc.

In a message dated 8/10/2004 8:32:32 PM Eastern Daylight Time,
bussema@... writes:

Howdy. I have a few questions about encoders. . . the main one being: Is it
possible to use linear and rotary encoders interchangeably? If both give the
same quadrature feedback. . . is there even a difference besides the obvious
mechanical differences (and price)? For that matter, I guess I could ask the
same of laser linear encoders. Has anyone tried to use linears on a small
machine tool? I would sure like to see some pictures, because it seems like
mounting them might be a little tricky.

Thanks,

John

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In my industry, woodworking machinery, both are used. The linear needs a
machined surface that is long enough to allow full travel over the encoder
strip and that can make mounting it a bit more of a problem. As far as cost
goes, that would depend upon the quality and resolution you would need, the same
would go for a rotary encoder as well.

Mounting rotary encoders might be a little easier as you can just mount them
on a shaft, such as the lead screw or even use a small timing belt and
pulley to drive them. Not as much room needed.

I have heard pros and cons regarding both. The biggest con regarding linear
is that you MUST protect the strip from being damaged and that can be a real
trick. Rotory encoders are fairly easy to protect with just a cover over
them.

Well, hope this helps some.

Randy Abernathy
4626 Old Stilesboro Road NW
Acworth, GA 30101-4066
Phone / Fax: 770-974-5295
Cell: 678-772-4113
E-mail: Cnc002@...

I furnish technical support, repair, and other related services for your
industrial woodworking machinery. My background as Senior Service Engineer for
the SCMI Group for nearly fifteen years with factory training, combines with
my extensive background in electronics, mechanics, pneumatics, electrical and
CNC machinery to offer you needed support for your machinery.


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