The customer’s request
Our customer contacted us about making an automated assembly system for an engine mount for a major automobile manufacturer. Not an uncommon request, until we found out the idea was to create an automotive engine mount filled with fluid, a hydraulic engine mount. Our customer brought us the parts and part designs and asked us for custom automation equipment needed to assemble the mount.
Their goal in requesting this automated equipment was multi-fold: Remove the human element, limit the number of machines required to assemble and increase the production rate.
The challenges and solutions
There were a few challenges along the way. The first was developing an entirely new process. The part required the completion of multiple assembly processes along with verification of correct and successful assembly. At the time we built the equipment, there wasn’t a machine that existed addressing all the requirements. This was a new part, requiring a new assembly process.
Another challenge was manufacturing the interior of the engine mount. The fluid passageways within the interior of the engine mount are particularly complex. Inside the mount, the orifice assembly –made up of a plastic body, rubber membrane and steel plate –had to be staked via hot air cold stake, prior to placement within the engine mount. The stake pins for the process were so close together, specialized tooling had to be created.
Additionally, there are five different components requiring assembly prior to the part being filled with fluid. The assembly process for each component is a little bit different. The engineering team had to sort out how to fit all the assembly processes for each component within one machine. The components of the part had to be swaged down before they could be assembled. The swaging process had to be built into the machine to not only fit the parts within each other but also seal up the mount before adding fluid.
Lastly, when the mount has the air vacuumed out and fluid is injected in its place, if any amount of air is still present, the part will fail the inspection test. A tremendous amount of research and development went into ensuring the removal of all the air and the subsequent replacement with fluid within the required cycle time. To complete this, engineers developed a specialized valve that didn’t exist before. It is a 3-way valve that engages the engine mount and shifts from vacuum to fill within the cycle without ever disengaging from the part and without letting any air in.
The finished machine
Arnold Machine built the assembly machine using laser cutting, CNC forming, welding, CNC milling and turning. The machine utilizes a Fanuc robot, hydraulics and custom built tooling to assemble the components together and then crimp and seal the mount. Once sealed, the mount is moved to a station where the 3-way valve is affixed, air is vacuumed out, glycol is injected to fill the mount and an o-ring rivet replaces the valve to seal and finish the process. The total machine cycle time is less than 45 seconds.
The final result is a single machine that removed the human element from difficult to verify processes and provided an increase in production rate while maintaining consistency and accuracy.
This dry fill hydro-mount assembly machine is merely one of the many customized solutions we’ve provided automotive manufacturers from around the world. If you’re ready to begin discussing tailored solutions for your business, contact one of our automation experts.