in older posts, I presented our current solution for pick+place of e-chain parts. Cycle time of 5-6 sec/pick is the most critical issue (we can not operate much faster due to missing stiffness of the igus arm). We now solve this issue by using our arms on drylin rails, in addition we use 2 units to feed one mounting unit.
Result: reduction of cycle time!
We expect a final cycle time of 2,5 sec with this “5+1” unit (or better 2x(5+1): 2 drylin carriages and 2 pcs roboolink arms with 5 DOF). We will present the new mounting unit in operation at SPS show in Nürnberg by the end of NOV. Sales price for total 12 DOF unit will be BELOW 10.000,- € (detailed pricing will be announced at SPS show). We use BECKHOFF control parts here.
We supply 2 options of encoders for our joints / joint arms.
Option 1 (our Standard before HMI 2017): Motorencoder plus Ini switch for 0-point reference on the joint output (PRT bearing)
Option 2): Output encoder on the PRT bearing of the joint. This is our own development, we use a magnetic ring plus Encoderchip on the output with an aditional magnet and Hall Sensor as reference point. Please find attached a description of the output encoder attached in GER and ENGL. Advantage: less cables, higher resolution, more accuracy for the arm.
We have defined 3 different quality standards for our robolink D joints and I want to explain the background of this issue. The 3 qualities are:
The main performance differences are stiffness, friction, precision (reverse play) and on the other hand cost. For size -20 and -30, the price difference between low cost and high end is ~factor 2, for size -50 it is ~factor 1,5. standard version ~ in the middle.
The high end version contains of our lubrication free worm gear with worm wheel made of iglidur J and worm shaft made of aluminum (hard anodized), it has ball bearings for the axial shaft load and for the back side (only version 102). The outer bearings are our PRT-01-xx (= high end rotary table made of aluminum with sliding elements made of iglidur J). Housing and inner connection parts are made of moulded plastic parts (our RN33), screws and nuts are stainless steel.
Most parts of the standard version are the same, but the back side has a sliding bearing (iglidur J) instead of the ball bearing (only version 102) and the PRT itsself is version PRT-02-xx-AL, which is a low cost version of PRT-01-xx. It has more plastic parts and thus is much lighter. Compared with PRT-01 is is a bit less stiff and a bit less precise. In a performanmce comparison of the to joints, we see no big differences for most applicaations as long as we do not get to the limits.
The low cost version of our RL-D in comparison contains a moulded plastic worm shaft and sliding axial bearings instead of the ball bearings. Also the PRT is not build with an aluminum outer ring but a moulded plastic outer ring (PRT-02-xx-LC). Friction is higher and precision worse than our “standard” version. It should be used only for “easy applications” as for example hand adjustments.
For size -20 and -30, all versions are available. For size -50, only version “high end” is available, as PRT-02-50 is yet under construction. We will have it in ~OCT 2015.