Citation
(1998), "Award-winning toolchange", Aircraft Engineering and Aerospace Technology, Vol. 70 No. 1. https://doi.org/10.1108/aeat.1998.12770aab.011
Publisher
:Emerald Group Publishing Limited
Copyright © 1998, MCB UP Limited
Award-winning toolchange
Award-winning toolchange
The award-winning Bridgeport 22-station toolchanger carousel, which originally comprised 160 parts and weighed 15kg has now been superseded by a new version consisting of 22 identical segments and weighing 5kg!
Benefits to users are faster toolchange times, down from 7.5 to 5.2 seconds; increased tool storage capacity from 20 to 22 tools; easier servicing; and reduced downtime.
One of the biggest problems engineers face when designing rotating assemblies, such as toolchangers, is that of reducing the mass to be accelerated and decelerated without compromising the strength, stiffness, creep and flex fatigue resistance and reliability of the whole assembly. Quite a tall order.
Bridgeport's
upgraded award winning toolchanger which allows accurate selection and transfer
from up to 22 tools at high speed
Seeking ways of designing a new toolchanger for the (then) model VMC 760 Vertical Machining Centre that would be both faster and able to carry heavier tools than its predecessor, Bridgeport engineers decided to make significant use of DELRIN, an engineering polymer from DuPont. The wedge-shaped segments, with integrally moulded spring fingers which hold the tools, slot into one another to form the whole carousel including the drive mechanism. In the event of a segment being accidentally damaged it can be replaced in minutes.
The new toolchanger is now available for use across the whole Bridgeport Vertical Machining Centre range, from the VMC 600 upwards, as well as being an option on the new VMC 1500 portal machine.
Prototypes were tested in a simulator for an equivalent of ten years' normal use before Bridgeport went ahead with its introduction and engineers say that an analysis of service reports shows that it has now established for itself a proven track record for reliability.
Details from Bridgeport Machines Ltd, PO Box 22, Forest Road, Leicester LE5 0FJ. Tel: 0116 253 1122; Fax: 0116 253 9960.