Product category:
Control systems, DROs, etc, for machine tools
News Release from: DigiBall Division of L R Petrie | Subject: DigiBall DRO system
Edited by the Manufacturingtalk Editorial
Team on 22 November 2006
Robust linear encoder added to PC-based
DRO system
A new, tough linear encoder that has exceptional IP68 ingress protection is now available for the high-end DigiBall DRO system.
A new, tough linear encoder that has exceptional IP68 ingress protection is now available for the high-end DigiBall DRO system This robust incremental linear encoder compliments perfectly the DigiBall PC-based DRO system and is ideal for fitting to all types of conventional machine tools including mills, lathes, and grinders - and is particularly suitable for installations where a high degree of accuracy and reliability is required over many years say, for instance, in a maintenance department or RandD facility
This article was originally published on Manufacturingtalk on 8 Nov 2006 at 8.00am (UK)
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Free CAD viewer added to PC-based DRO system
The PC2DRO+ software of the DigiBall DRO system now includes a powerful 2-D CAD viewer that also displays axis readings on the same screen to increase operator productivity.
PC-based DRO system has USB connection
A PC-based digital readout with USB connection interfaces compatible ball-type linear encoders to a PC, laptop or notebook - and interfacing to glass-scale linear encoders will follow.
Careful attention to design detail enables this rugged linear encoder to work accurately, reliably and consistently in the harshest of workshop conditions - even when totally submerged in contaminated oil, dirty coolant, hot swarf, sticky sawdust, grinding dust, debris, or perhaps, outdoors in driving rain and snow.
The DigiBall linear encoder is a truly "fit and forget" product that is highly tolerant to shock and vibration: with a workshop usable accuracy of +/- 0.01mm per metre; resolutions as small as 0.005mm; a repeatability of 0.005mm; an operating speed of up to 2 m/s; and with the really big benefit of the encoder never needing any regular cleaning.
Innovatively, the encoder reader head occupies only about 75% of the space volume of its nearest equivalent competitor system, enabling the DigiBall encoder to fit easily into small spaces.
Further reading
Large CNC millers/machining centres introduced
C Dugard, UK, is introducing CME bed-type and floor type CNC borer/miller/machining centres, which include ram-type universal head and travelling column designs with up to 20m of travel in the X-axis.
Floor-type HMC has X-axis travel of 6m
For machining medium sized components, Asquith Butler has introduced its PowerCentre - S , floor-type horizontal machining centre with standard X-axis travel of 6m.
CAD/CAM reduces overall CNC milling costs
VX Corporation claimed that to machine cavities and pockets safely and efficiently, its SmoothFlow CAD/CAM maintains constant material removal and reduces roughing time.
This reader head comes with a standard 3.5 metre long connecting cable, additionally protected by a flexible stainless steel conduit cover, and has a 9-pin D-type connector that plugs directly into the standard DigiBall PC-Decoder.
Other cables lengths of up to 6 metres are also available.
The fitting of DigiBall linear encoders to any machine is extremely simple and requires the making of only four tapped holes.
Two of these are for the M5 cap head socket screws that fasten the reader head to the axis slide.
The other two holes are for the M8 studs that fasten the very effective universal brackets which self-align the BallScale to the reader head.
These brackets dispense with the usual need for machined surfaces and/or backing bars that are typical of other DRO systems.
Working on well-tried and tested electromagnetic principles developed over the years, the innovative DigiBall encoder uses a completely sealed reader head that traverses over an equally completely sealed BallScale.
The encoder design does not rely on rolling bearings of any type whatsoever - thus ensuring years of trouble-free service for the user.
Prior to the introduction of the DigiBall linear encoder, and to be certain of their ruggedness, for the last five years pre-production prototypes have undergone extensive testing.
This testing took place not only in machine shops throughout the world, but also in selected gold mines located in the harsh Western Australian desert and on commercial fishing boats working in the cyclone prone Indian Ocean.
This type of testing closely mirrors the DigiBall ethos - that there can never ever be a real substitute for quality manufacture and rigorous testing.
To this end, the DigiBall linear encoder uses only parts machined from solid materials, unlike other makes of linear encoders that usually include a plurality of cheaper die-castings.
This concept of inherent quality extends throughout the manufacturing process with, for instance, the whole reader head assembly being stress cycled at low and high temperatures in a specially constructed environmental chamber for 72 hours.
Only after passing this exacting test, is the reader head then finally calibrated in a dedicated calibration room maintained at a constant temperature of 20C.
Immediately after calibration, the reader head is finally epoxy potted for IP 68 protection.
The manufacturing specifications for the BallScale are no less stringent with, as another example, only centreless-ground, cross-woven, carbon fibre tubes used for their construction - to ensure a truly non-magnetic and temperature stable measuring reference.
However, it is the secret know-how, used in the magnetic grading of the ultra-precision steel balls which are used in the DigiBall linear encoder, that really distinguishes these quality products from those of competitors who use similar technology.
Indeed, the use of this expertise means that every single nickel chrome ball is graded magnetically no less than four times - thus ensuring exemplary accuracy in the final BallScale assembly.
With a pedigree such as this, it is no small wonder that every DigiBall encoder has a six-year, no questions asked, warranty - believed to be the longest and best in the DRO business.
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