GRS makes it possible to build flexible computerised systems where the robots can be transferred to a specific production or assembly line track using the most space efficient layout for the factory.
Lucas needed a Heavy Duty routing system comprising a centralised length of track 2m long where robots are positioned prior to being transferred. Track lengths are typically 10-20m long.
Transferring a 2 tonne robot from a centralised station to a remote track by first rotating the holding station up to 360 degrees and lining up with a track is not without a number of technical challenges. Unless guides and drive racks are aligned exactly making the transfer would be difficult if not impossible without damaging the system.
Lucas use their own proprietary steel construction beam and fit HepcoMotion HDS2 guides CHSS25NK in parallel spaced apart 350mm. The central rotating station at 2m long is shorter than the gap between opposing tracks to allow rotation. This means that having rotated the station to line up with the requisite track, it has to be indexed to butt to the mating track so the transfer can take place.
This is achieved by a clever cam mechanism that locates in the central station and pulls the whole station towards the track until it makes contact.
For the main assembly tracks the precision CHSS25 NK – HDS2 guides are available in lengths up to 4m in one piece, for longer lengths they can be butted. The immediate problem, though, is controlling the central station 2m guide lengths accurately so that there is no joint gap when the central station is indexed.
At the end of the guides HepcoMotion machine an angle in two planes so that the V bearing will cross an angled butt joint as opposed to a square butt joint. This and tight size control of the V profile size together with ensuring the guides are the same length ensures a successful transfer.
– HDS2 – CHSS25,
– CHSS33 single edge slides cut to length plus THJR95,
– 120 or 150 bearings depending on robot
The whole system is very low maintenance, V technology only requires small amounts of lubricant to spread over the V guide surfaces to achieve a long and trouble free life. Low maintenance cap wipers are fitted to completely cover the bearings preventing the ingress of dirt and apply the lubrication. With the cap wiper felts soaked in oil they will perform for long periods without the need for re – lubrication.
In most cases grease is supplied as the lubricant and the action of the bearing rotating within the cap seal effectively liquefies the grease and feeds the lubricators. With such high duty robot assembly systems the HepcoMotion standard bleed lubrication system fitted to the guides with time regulated canister will ensure no maintenance for at least 6 months.
The Gear Robot System can handle payloads from 100kg to 6 tonnes. Within the medium load range, HDS2 guides with V bearings 95, 120 or even 150mm diameter are used. For the top load range the HepcoMotion MHD system which uses large diameter rollers running on hardened and ground flat track will offer a higher load capacity with all the inherent benefits of HDS2.
GRS is targeted as an innovative solution for moving cartesian, polyarticulated and “hybrid motion” robots, however, potential users will find the principle of the system highly useful as a means of feeding parts to specific production lines.
This sort of application can be seen in many production facilities, the robot could easily be replaced with a tooling fixture or carrier for storing components.