Re: [CAD_CAM_EDM_DRO] Re: VFD and inverter duty 3phase motors

In a message dated 7/31/2004 12:42:57 PM Eastern Daylight Time,
greg@... writes:

High end machine tools will vary bearing preload on the fly to get over this
problem.



Yes and the bearings and designs for this are rather expensive. In the
woodworking industry we run most spindles at 18,000 rpm or higher. However, many
plastics fabricators are using machine tools designed for the woodworking
industry and also a lot of the display manufacturers are doing the same. This
means that the spindles need to be able to run, in some cases, below 1,000
rpm, then the next application may require they go back to the higher spindle
speeds. The spindle motors for this are not very cheap and the bearings they
use aren't either. Perske is probably the best known supplier of motors for
these applications. There are some others like HSD (High Speed Devices), a
division of the Biesse Group in Italy and also Columbo another Italian high
frequency motor OEM.

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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