Shown: the follow-on four-machine cellTwo Robots, Three Spline Rollers, One Operator
Robotic cells took over loading three spline-rolling machines, cut the crew from three people to one and kept the line running through breaks.
A manufacturer of spline shafts for truck and four-wheel-drive transfer cases was loading three spline-rolling machines by hand. It took three people, bins of half-finished shafts moved by fork truck, and production stopped at every break.
Han-Tek built two identical robotic cells, each with two FANUC robots, dual grippers and a pallet conveyor. The crew dropped from three people to one, the cells beat the 21-second target with one spline every 18 seconds, and the line now runs three shifts a day.
Three machines, three people, and nothing ran at break time
Each shaft goes through three spline-rolling machines, which press the teeth onto the shaft so it can lock into a transfer case. People loaded and unloaded every machine by hand.
Uneven pace
Each person loaded and unloaded at a different rate, so output varied.
Bins and fork trucks
Bins of half-finished shafts had to be moved from one machine to the next.
Breaks stopped the line
When the operators stepped away, spline rolling stopped.
The goal: one finished spline every 21 seconds, with less labor and less downtime.
Two robots pass each shaft through three machines
Han-Tek designed, built and installed two identical robotic cells. Here is how a shaft moves through one.
- 1
Load a pallet
The operator loads four blank shafts onto a custom pallet, which rides the roller conveyor to the robots.
- 2
Robot 1: machines 1 and 2
With a part in each side of its dual gripper, Robot 1 swaps a blank into machine 1, then carries the finished part to machine 2.
- 3
Robot 2: machine 3 and back
Robot 2 moves parts from machine 2 to machine 3, then onto an outfeed pallet that returns to the operator.
- Shared machine, no collisions: a programmed handshake lets both robots work at machine 2 without interfering.
- Smart pallet handling: the robot finds the next available shaft without wasted motion, and empty pallets shift to the outfeed automatically.
- Restart where it stopped: after any shutdown, the robots pick up where they left off instead of starting over.
- Safe entry: request-to-enter moves the robots to a safe stop, and opening any fence door shuts the cell down.
- Tested first: each cell was set up at Han-Tek with mock-up machine fixtures, and run off with part-number changes and each machine taken offline in turn.
One operator, faster than the target, running through breaks
| Area | Before: manual | After: robotic |
|---|---|---|
| People to run three machines | Three | One |
| Cycle time | Goal of 21 seconds | One spline every 18 seconds |
| During breaks | Production stopped | Robots keep running |
| Moving parts between machines | Bins and fork trucks | Robots, machine to machine |
| After a stoppage | Start the cycle over | Resume where it stopped |
| What came next | Two cells, three machines each | Repeat order for a four-machine cell |
- About 67% less labor: two of the three people were no longer needed to run the machines.
- Faster than required: one spline every 18 seconds with both cells running at 80%, beating the 21-second goal.
- Uninterrupted production: pallets accumulate at both ends, so the cells run three shifts a day, 365 days a year.
- Safer maintenance: request-to-enter and interlocked fencing keep people clear of moving robots.
- Repeat order: in 2004 the customer came back for a cell serving four spline rollers, again with two FANUC M-710iB robots and dual grippers, on a continuous-loop pallet conveyor.
Questions about robotic machine tending
Can two robots share the same machine?
Yes. In this cell, both robots work at the second spline-rolling machine, and a programmed handshake keeps them from interfering with each other.
How does a robot cell keep running during breaks?
Pallets of parts queue up on the conveyor at both ends, so the robots keep loading machines while the operator is away.
What is a dual gripper?
A robot gripper that holds two parts at once. The robot pulls the finished part and drops in the next blank in one visit, which saves a trip on every cycle.
Can a robot cell be tested before it reaches our plant?
Yes. These cells were set up and run off at Han-Tek with mock-up machine fixtures to confirm cycle times before shipping.
More robotic machine tending projects
Let robots do the loading.
Tell us the machines, the parts and how many people it takes today. A Han-Tek engineer will tell you what a robot cell could do.
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