New Valves Simplify Robot Arm Wiring

New valve technology from IMI Norgren Inc. (www.norgren.com) is simplifying the wiring and plumbing of factory robots, in some cases reducing pneumatic manifold change-outs from 30 minutes to as little as three.

Norgren engineers say that the company's new VM10 valve islands are being employed on industrial robots made by Kuka Roboter GmbH, where they reduce end-of-arm cabling and tubing. Furthermore, they say that the design's light weight enables users to mount manifolds at the end of a robot arm.

The design is being tested out on an assembly line where automotive engine connecting rods are loaded and unloaded for precision machining and grinding. There, the VM10 valve islands mount directly on the end of the robot arms, which employ pneumatically powered grippers, rotary actuators, or vacuum cups, to move the connecting rods.

"Ordinarily, the manufacturer would put the valve manifold away from the robot in a more stable area, and then run the tubing along the robot arm to the different actuators," explains Bradlee Dittmer, product line sales champion for valves and fittings at Norgren. "But instead of having the manifold back on the assembly line, this design allows them to bring it right out to the end of the robot arm."

By doing so, Kuka needs only to run a single pneumatic line out to the manifold, and then run separate lines across the short distance from the manifold to the actuators. In contrast, industrial robots often have up to eight separate pneumatic lines running along the length of the arm.

Electrical wiring in the robot application is similarly reduced because the VM10 is endowed with field bus connections and protocols. The Kuka application requires only a single, twisted-pair wire, using a field bus protocol, running the length of the robot arm.

"That's a big part of reducing the complexity," Dittmer says. "If you have an eight-station manifold with double-solenoids, you would have 16 wires. Here, we only have one."

Norgren also reduces the size of the manifold by incorporating field bus technology right into the V10's printed circuit board.

For time-conscious manufacturers, however, one of the biggest advantages of the new design might be its use of an aluminum sub-base known as Pneumapole. The sub-base incorporates all of the fittings and connections, and can be easily disconnected from the manifold. By doing so, the Pneumapole sub-base reportedly enables assembly line users to swap out a hard-wired, hard-plumbed VM10 manifold in as little as three minutes.

"Even if you just need to change one valve, this allows you to quickly pop the manifold off, and pop a new one on," Dittmer says.