The company investigated alternate methods of harness assembly. "We didn't even consider resistance welding or clip and dip soldering. They were just too labor intensive," said Freimuth. Ultrasonic splicers, which were recommended to the company by a wire harness expert, have long been used in the automotive industry (see sidebar). For many years, large OEM suppliers have used ultrasonic welders because the welds produced can withstand the rugged environment an automotive harness is subjected to, including vibration and corrosion. "Bikes are out in all kinds of weather and we wanted to eliminate any possibility of corrosion," said Cook. "We had already decided to go to a sealed connector system, but we were unable to accomplish that with our previous bench termination method."
A decision was made to redesign the FLT's harness in order to accommodate the use of ultrasonic splicers. Says Friemuth; "Our harness redesign incorporated a sealed connector system. Wires are cut, stripped, and terminated as needed for production using our existing wire processing equipment. Terminals are applied automatically to one end of the assembly and the other end is stripped for ultrasonic splicing. Wires requiring ultrasonic splicing have both ends terminated with the automatic equipment."
"We've gained more in process capability than in process improvement," Freimuth continued. "Our setup person sets up and qualifies each splice, putting it in memorystorage. Selecting the right splice combinations is very simple because the splicer software is user-friendly. We selected a system that had a fully automatic setup."
"Our operators are extremely comfortable with the ultrasonic splicers," agreed Cook.
"They find them easy to use and very consistent. Any changes in sequence can be made with a touch of the finger. We've eliminated our bench top operations and our quality assurance is more controlled than with a manual process."
The mystique of a Harley Davidson cycle has not only been in its sheer automotive power, but in its appearance. Harley enthusiasts are well known for the value they place on the smallest detail of their vehicles. While many manufacturers have switched to ultrasonic splicing of harnesses for the cleanliness of the manufacturing process and lower utility costs, these were not issues at Harley-Davidson.
"Previously, we used an open air connections on the FLT's wire harness," said Cook. "With a typical automotive harness, everything is hidden under the hood, trunk, or body panel. On a Harley, the harness is in the open and part of the bike's cosmetic appearance."
"The new harness design allows for sealing the connection after the ultrasonic splice is made. A heat shrink with sealing adhesive is applied that not only protects the connection, but makes for a pleasing appearance on the outside of the bike. Styling and cosmetic appearance were big factors for us," explains Cook.
Manufacturers switch to ultrasonic splicers from other methods for a variety of reasons. Reduced maintenance cost, increased productivity, and improved quality are the three typical motivating factors for splicing ultrasonically.
