Medical Device Mfr. Upgrades Actuators and Saves $900,000 Per Year

A large medical device manufacturer in Southern California was faced with a dilemma.  A machine they rely on to manufacture most of a particular product was designed and, most importantly, certified for the medical manufacturing of this product.  The machine is very complicated and has more than 58 axes.  More than half of these axes are following either one or more virtual master axes and one or more real axes.  Many use cam profiles for their individual processes.  The dilemma arose when 12 linear actuators, manufactured by Exlar, had been discontinued.  These actuators were a roller screw and motor combination.  They were manufactured with a unique feedback system that was compatible with the drives that controlled them.  The medical supply manufacturer could not change the drive that controlled the actuators without replacing the entire control system on the machine, so they continued to send the actuators back to Exlar for repair.   Each time they did so, the people at Exlar told them that the day would come when they would not be able to get the actuators repaired.

Since Valin was familiar with the control system used on this machine, the medical supply manufacturer reached out to us for help.   After performing an analysis on the performance of every actuator on the machine in production, Valin specified a Parker ETH80 electric rod-style actuator similar in form factor to the existing Exlar actuators.  This included a wrap-around motor mount, gear box and a replacement motor compatible with the existing drives and controls.  The actuator was customized with a special front flange mounting kit with all the dimensions necessary to ensure it would bolt directly in the same location as the old Exlar actuators without modifications being necessary for the mounting.  The hole pattern and rod end were all made to be exact replacements for the existing Exlar actuator.
The second step in the process to getting the solution certified was to back up every parameter for a single axis and then set up the drive to work with the new actuator and motor.  The actuator was dry tested on the floor to confirm its functionality, then tested in a simulated production of the machine.  The original Exlar actuator was returned to service until the Parker ETH actuator replacement was certified for use on this medical machine.  Having passed the certification, the customer is waiting for approval for their capital budget to purchase 11 more actuators for production and 2 spare actuators.  

By converting the machine from the Exlar actuators, Valin is saving the customer at least $500,000 for a complete controls upgrade…not counting the loss in production for the extensive time the machine would be inoperable.  

This upgrade design also includes a feature that potentially saves the customer hours every day in unproductive down time.  The new motors used on this retrofit have multi-turn absolute encoders which no longer require homing like the existing axes did.  This saves the customer about 15 minutes re-starting the machine every time there is a jam or recovering from an emergency stop situation every time the e-stop button is pressed. 15-minutes down costs the company at least $500.  Re-homing the machine 5 times a day on average means that the new feature will save the customer $2,500 a day which is over $900,000/year if they operate 365 days a year.

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