Engineers are increasingly incorporating advanced electronic systems into today's automobiles. The automobile's growing electronic content is creating huge new business opportunities for processors with the right molding capabilities, and will change future materials requirements as OEMs prepare to convert to a new power technology.
April 1, 2003 by Michael R. LeGault, editor
Electronics were in the spotlight at this year’s Society of Automotive Engineers 2003 World Congress in Detroit, and for good reason. As keynote speaker Hans-Georg Frischkorn, BMW senior engineering vice-president, electric/electronics, observed in his speech to show attendees, electronics technology now dominates the automotive industry, accounting for 90% of innovation taking place in new vehicles. Plastics is playing, and will continue to play, a critical role in the design and development of these new electrical systems.
Indeed plastic is one of the key, integral materials of the on-going automotive electronics revolution. Applications for plastic include everything from “internals”, such as circuits and switches, to under-the-hood housings and instrument panel control clusters.
PLASTIC BELLS AND WHISTLES
A new seat-belt technology from TRW demonstrates how the increasing use of electronics is driving new plastics applications and greater plastic content in today’s vehicles. The device, called a reversible belt pretensioner, gives the driver and other vehicle occupants enhanced protection compared with conventional seat belt systems. The device works by assessing vehicle dynamics before a crash. In the event that the electronic sensors detect a pre-crash condition, an electric motor is activated to minimize seat belt slack.
Plastic is an important part of this application in two respects: First, the motor is activated by an electronic control unit (ECU), the heart of which is usually some type of circuitry embedded in high-heat resistant plastic or components contained in a plastic module. Second, several components of the reversible seat belt pretensioner, including housing, parts of the motor and seat belt roller, are plastic.
Siemens VDO Automotive AG has introduced the first car instrument-panel cluster with a thin-film transistor (flat panel) display system. The system, which was first introduced in the new Audi A8, points to the future direction of advanced driver information systems laden with hosts of bells and whistles. The flat panel display is actually the heart of the car’s multimedia interface (MMI). Situated in the middle of instrument panel console, the MMI provides the driver with car-function, navigational and other data. Much of the MMI, including display screen housing, interface buttons, circuit backing materials, is manufactured of various grades of plastic.
BMW’s Frischkorn sees these and other new electronic-based features of automobiles as being driven by three revolutionary trends. The first is that vehicles are becoming more attached to the Internet and must now be capable of receiving data such as GPS navigation data, telephone numbers and e-mail. Another driver of change is the so-called “X By-Wire” technology, which is being used to replace previously-based mechanical systems, such as acceleration, with entirely electrical systems (See sidebar “42-volt system will require new materials”). Lastly, Frischkorn said the demand for creature comforts and personalization, such as back seat entertainment and pre-set seating positions, will continue to influence the way new vehicle models are designed.
“The amount of software in a car is doubling every two to three years, and we do not see that changing in the next generation of cars,” Frischkorn observed. “Software is at the point where it will increase to about one-third the cost of a car in the next few years.”
PROCESSORS REAPING SPOILS
The evolution of the increasingly electronic car has boosted demand for electronic components such as switches, connectors and other electronic controls and assemblies. The result has been a boom in business for processors with specialized molding capabilities and the right position in the supply chain.
Polymer Technologies Inc., based in Cambridge, ON, is one of those. Five years ago the Tier 2 automotive supplier had one large customer who accounted for over 50 percent of the company’s sales. Today, it has eight major clients, including Magna International, TRW and Valeo. Customer orders for the company’s high-end, electromechanical switches, relays and other components have resulted in an unprecedented sales surge. In the last 12 months Polymer’s annual sales have grown to $50 million, from $30 million. In this twelve-month period Polymer has put 120 new tools into production and hired 200 additional employees.
“We’re finally seeing the pay-off from our strategic initiative to diversify our customer base,” said Michael Ritchie, business development manager, during the SAE show, where the company was exhibiting as part of the Canadian pavilion.
The company displayed clusters of small, intricate plastic parts inlaid with electrical circuits, connectors and graphics. The parts are made by specialized plastic injection molding processes such as insert molding and two-shot molding. For insert-molded parts, Polymer stamps the metal and molds the final plastic part; as well, handles other auxiliary production operations such as printing and contact welding. The company has its own tool room, but also outsources tooling to a number of moldmakers in the U.S. and Canada.
Ritchie reported that the company has purchased approximately 10 new injection molding machines in the last year, including a number of vertical rotary presses. In total the company now has 60 injection presses, which are roughly split between horizontal- and vertical-style machines.
Polymer has invested heavily in custom automation in order to further enhance efficiency and stay a step ahead of the competition. One of the company’s automated lights-out production line produces steering column components, including an air bag sensor, from metal stamping to final testing, without any direct labor.
The influx of new business is the result of a strategic business plan put into place in 1996 when CEO and owner John Bell bought the company. At the time, Polymer was a manufacturer of commodity cosmetic packaging with flat sales of about $9 million annually. Bell moved the company’s business in the direction of more advanced engineered components, a decision he said was based more on the necessity to change and survive than it was on insight that automotive electronics molding would take off.
“The growth in electronics systems in automobiles has definitely resulted in new business for us, but we’ve just been in a position to be reactive to the movement,” Bell said. “We’re too far down on the food chain to influence these types of trends.”
Such quick growth has required an all-hands-on-deck approach at Polymer’s 65,000 sq. ft. facility in Cambridge, ON. The company’s 470 employees are working three shifts, seven days a week to meet all customer orders. At the same time, Bell and his staff are laying the groundwork for the company’s next phase of expansion.
“Within the next year we’ll have a second presence, either in the U.S. or Canada,” he reports. Bell said the company is considering several scenarios, including building a new plant near its current facility, or acquiring existing capacity in a buy-out.
NEW MOLDING PROCESSES, PRODUCTS CATCHING ON
Tricon Industries (Lisle, IL) has legitimate claims as one of the pioneers of high-precision insert molding to make electro-mechanical parts and components. In the early 1960s, IBM contracted the company to manufacture a series of switches for its consumer products. Tricon used a combination of new manufacturing techniques, including insert molding and contact welding, to meet and exceed IBM’s specifications.
Jeff Terrell, manager of product development, said the company is using this experience and expertise in electronics molding to bring a number of new products to the market. It has introduced a new Miniature Universal Socket that provides customers the twin benefits of parts consolidation and cost reduction.
The Miniature Socket interfaces with the insert-molded backplate through a simple snap-in feature. The backplate is molded using Trexel’s MuCell molding technology. The design allows the insert-molded circuit to be routed accordin
g to a variety of design and styling needs, and eliminates the need for a separate pigtail connection in a backplate design.
Terrell said MuCell molding has potentially huge applications in the manufacturing of electrical/electronic components. MuCell is a microcellular foaming process that can be incorporated on standard injection molding machines. The process introduces a supercritical fluid into the molten plastic, reducing viscosity of the melt up to 60%. Reduced viscosity in turn provides a number of advantages, including reduction in cycle time, reduced clamping tonnage, reductions in injection pressure and lower processing temperatures. As the microcellular foam sometimes produces a swirling pattern on the surface of the part, MuCell is generally limited to parts with no cosmetic or appearance requirements.
“This process is ideal for molding electronic parts,” said Terrell. The MuCell-molded Universal Socket is presently undergoing PPAP validation prior to full commercialization. “With this socket, we obtained a 30% reduction in cycle time and a 10% savings in material by going with MuCell.”
These benefits aside, Terrell said MuCell provides a host of other, more significant advantages for molders of automotive electronics. Lower injection pressures means there is less likelihood of blowing out stamping inserts from the mold, reducing costs for pre-mold fixtures and labor to hold the inserts in place. Lower processing temperatures allow complete encapsulation of the electronic circuit in one-step, eliminating any re-soldering. Lastly, Terrell said they have found that MuCell can get rid of warpage in certain types of parts by relieving molded-in stresses.
Tricon has a 110-ton Arburg machine dedicated to running MuCell. The machine can be adjusted to run injection in either a horizontal or vertical configuration, and gives production the flexibility to do “parting-line” injection.
“This one more thing in our toolkit we can offer customers,” said Terrell. “As an automotive supplier today, you need to bring something to the table.”
42-VOLT SYSTEM WILL REQUIRE NEW MATERIALS
The present 14-volt power system in automobiles was adopted in the 1950s and, at tops, can generate about three kilowatts of power. In the near future, vehicles will require between six to 10 kilowatts.
“The old 14-volt system has simply run our of power,” says Dr. Bill Hsu, vice president, DuPont Engineering Polymers.
The replacement power system, 42-volt technology, has already been launched in the Asia-Pacific region. With a more complex mix of vehicle types, North America will likely see 42-volt in automobiles sometime within the next 10 years, according to engineers polled in a survey conducted by DuPont Automotive at the SAE World Congress in Detroit.
Current automotive electrical systems are becoming overtaxed by the increasing number of electrical devices designed into today’s cars and trucks. However, the main reason car companies are interested in 42-volt technology is that it will allow engineers the freedom to convert hydraulic and mechanical systems, such as steering and braking, to electrical, and thus improve fuel efficiency, lower emissions and reduce maintenance. The method by which this conversion will be carried out is referred to as “X By-Wire”, where X is any system being electrified.
According to Jim Hay, global director for DuPont’s Advanced Automotive Electrical/Electronics (AAEE) project, 42-volt technology will require the use of new thermoplastic materials in automotive design.
“42-volt technology will compel the use of materials with physical and chemical properties different than many of the plastic materials currently used,” Hay says. He notes that many of the components comprising the electronic controls and electrical distribution systems (housings, connectors, relays, etc.) will require higher heat resistance, EMI shielding, di-electric and other properties.
Hay says DuPont is working on specific projects, some already commercial, which will have applications in future 42-volt systems. For example, the impeller and housing of the electrical water pump in Toyota’s hybrid car, the Prius, is made of Zytel HTM, a specialty grade of high-heat resistant nylon. As well, the company’s Kaltrel resin was used in the development of heat exchangers for an all-electric air conditioning system.
Dupont Canada Inc.
ELECTROMAGNETIC INTERFERENCE A NEW WORRY
The modern automobile’s growing reliance on electronic systems has presented engineers with a new problem: the increasing potential of interference from radio and microwave frequency emissions from such sources as cellular towers, drive-though windows, high-voltage power lines and airport radar.
Many automotive engineers are now stressing the need for more comprehensive electromagnetic compliance testing. At the recent SAE show, one supplier, Siemens VDO Automotive, touted its advanced electromagnetic compliance (EMC) simulation tools for isolating and resolving electromagnetic interference scenarios in automotive electronics.
EMC simulation functions as a risk management tool, expediting a product’s time to market by determining EMC during the design phase. Since EMC behavior is affected by the electromagnetic environment in which the product is exposed, simulations use virtual tools to model certain characteristics of physical elements. Siemens says its common simulation tool enables different and incompatible analysis data to be universally transferred, allowing EMC simulations to be run worldwide.
Siemens Automotive VDO