Iscar Metals
Interiors: Craftsmanship And Innovation: Low-Cost Craftsmanship

Expanding the capabilities of standard injection molding machines is key to JCI's CrafTec process

The trend toward hard plastic interior parts started to take hold in the late 1990s, and continues to accelerate. However, these materials often fell short in terms of craftsmanship. To compensate, soft-feel coatings and fabrics were added in tactile areas to give "high-touch" elements an upscale feel. However, weight, panel thickness, and cost all increased. At the same time, entry-level vehicles–where differentiation comes through color, not fabrics–became increasingly monochromatic. Adding colors to the basic palette required a second tool set, and added time to the injection molding process. With OEMs squeezing suppliers for lower prices and higher craftsmanship and value, something had to give.

"We knew we had to act in order to meet the needs we noticed in certain segments of the market," says Dave Phillips, business development director, Interiors, at Johnson Controls (Plymouth, MI). Out of this need arose CrafTec, a contraction of the words "craftsmanship" and "technology," and two main processes: Partial Mold Behind (PMB) and Multi-Color Injection (MCI).

 

Partial Mold Behind

Conventional mold behind technology starts with an injection molded substrate wrapped with the fabric covering and then heat staked to a carrier. Not only are there multiple layers, it requires adhesives that can moisture cure in the lines as humidity levels change in the plant–necessitating replacement of hoses, valves, and fittings–and which give off VOCs that add to a plant's pollution footprint. "Since we were already melting the plastic in the injection molding process," says Phillips, "we decided to see if we could use it as a mechanical attachment that eliminates the need for separate carriers and adhesives." The process worked.

PMB takes die-cut material, places it in the injection molding machine, and injects the plastic substrate behind it. Heavier textiles, like vinyl, are pre-formed before insertion to get a good grain and depth-of-draw, and pre-formed decorative trim elements replicating wood, aluminum, or other materials can be added. "You have to make sure you have a good seal to prevent bleed-through of the plastic," says Phillips, "so we bond them by melting them together at the ditch joint prior to molding. We've found that if it'll hold water, it'll hold back the plastic."

An unexpected use of PMB has arisen with the move to stitched panels. A single piece of material is pre-stitched and inserted into the mold. The injection pressure squeezes the padding and grabs the stitch, giving it a three-dimensional look. "The single piece of material reduces the variation you'd get from using multiple pieces," says Phillips, "and allows you to introduce a variety of seam styles for different trim levels or to differentiate shared door panels."

 

Multi-Color Injection

Color, not fabric, is the main differentiator in entry-level vehicles. However, though insert and two-shot molding can create a homogenous two-color panel, reliability, craftsmanship, and speed suffer. "MCI has a moving part line on the tool," says Phillips, "and we shoot one color before quickly pulling back some lifters and shooting the second color right behind it before it has a chance to cool and shrink. It takes maybe seven seconds longer than a conventional one-shot process but the equipment is pretty standard."

In order to make MCI as cost-effective as possible, Phillips suggests that the spread between colors not exceed 70:30, though 50:50 is optimal. "At those ratios, you really begin to see a cost advantage compared to more conventional processes," says Phillips.

JCI envisioned hard instrument panels with thermoplastic olefins (TPO) upper and polypropylene (PP) lower sections, each in different shades or colors. Since both are part of the olefin family, there would be no trouble with bonding the two plastics, or concerns about recycling. A number of OEMs have expressed interest in this design, but their interest didn't end there. 

Based on MCI's quality level, an automaker suggested it be combined with a slush foam-in-place upper skin for a luxury SUV application. In this process, the skin is applied directly on top of the single piece two-color lower section, eliminating the need for a separate substrate, and the same process is used for door panels. According to Phillips, "It's a case where the customer got a little bit ahead of us, but the process was robust enough to accommodate what they wanted." Domestic automakers were the first to discover and use the CrafTec processes, but the Asians and Europeans aren't far behind. Given the competitive nature of the industry, JCI is working to expand its capabilities in order to stay ahead. "We know other companies are going to try to do the same thing," says Phillips, "but we're spending a lot of time and putting in a lot of effort to push these processes beyond where they are today. We have to keep reinventing the portfolio if we want to stay ahead."

 

Shelby GR-1 Gauges

Yes, this is an expensive, hand-built, one-off gauge cluster, but Robert Viscosi, program manager for the project at Stewart-Warner Performance (Lancaster, PA; [ www.sw-performance.com), says a production unit would look very similar. The two-in-one oil temperature/pressure gauge uses a miniature motor with a high-torque neodymium armature in place of the more common ferrite-filled plastic piece used in high-volume gauge clusters. Expect that to change if the GR-1 reaches production. Also, the analog tachometer with integrated digital speedometer has an LED pointer – a first for Stewart-Warner – and would be a challenge to bring to production. "We burned a hole with a diameter of 0.016-in. into the armature spindle that is itself a 1.0-in. long shaft with a diameter of 0.040 in.," says Viscosi. "Through that is threaded a fiber optic cable with a diameter of 0.010 in." For volume production, a less-expensive process would be required. Dual microprocessors – one for each function – are found on the combination gauges, with single units on each of the remaining instruments. Some have direct data bus interfaces with no sending device, and communicate directly with the vehicle's ECU. Package depth is 6.0 in. at its maximum, and encompasses an external watch-style bezel that sits atop the gauge package. The complete unit – there's only one – took approximately four months to design, develop, and build.


Dual-Depth Airbags

The 2006 Buick Lucerne and Cadillac DTS sedans feature dual-depth front passenger airbags. Unlike dual-stage airbags which inflate with different pressures but to a single shape, the Delphi design deploys to either a small or large size depending on seat position, seatbelt use, and crash severity. Inflation energy also is adjusted to one of two pressures according to crash severity. Delphi says the technology is compatible with existing restraint electronics, and requires no changes in vehicle architecture.

 

BE Cool: A New Approach for Seats

The outlook for one supplier of climatized seating systems is one where cooled seats are going to be hot.

"In North America, we have roughly 64% market share." That's Andreas Brand, president and CEO, of W.E.T. Automotive Systems Ltd. (Windsor, Ontario, Canada; www.wet-group.com). That rough estimate is of the piece of the heated seat market that W.E.T. has. (The acronym? From the German Wärmeund Electrotechnik, or warmth and electric technology.) W.E.T. started producing seat heating units for vehicles in 1973, based on the company's experience with mechanical cables and heating systems. The company now produces steering wheel heaters control modules, and wiring harnesses. As Rob Klein, Director, Sales & Marketing, notes, "We design and develop all of the components that go into a system."

While there is certainly experience and dominance in the heated seat arena, Brand thinks that the Next Big Thing for automotive interiors will be what he calls the "climatized seat." Some people might simply describe this as being the "cooled seat." In the case of what W.E.T. has developed, this goes beyond simply blowing conditioned air on the driver in order to cool her down. Brand says that it took some 12 years for heated seats to get penetration on the order of 20 to 25% of the market (starting with the European luxury brands, then proliferating downward and to North American and Asian products). He thinks it will take about half of that time for the cooling function to achieve the same level of acceptance in the market. One of the factors that he sees driving this is actually coming from the Asian vehicle manufacturers, who are considering offering the cooled seat on cars at a price point of $30,000 or less. Consequently, this will not only be a case where the heated and cooled seat is available in the premium vehicles, but also for those that are significantly less expensive.

THE COOL APPROACH. The cooling systems that W.E.T. has developed are of two types. One is ComfortCools; the other is ActiveCool. The former includes at least one mechanical blower. However, rather than blowing cold air at the occupant, the ambient air in the vehicle is drawn through the seat, thereby removing heat and moisture from the individual. The blower also acts to circulate air. It works in conjunction with the heating system, as well. The design of this system is said to have a minimum impact on the seat design, such that it can be introduced as a mid-cycle option. One of the things that Brand emphasizes when talking about what W.E.T. brings to the table is systems integration: it isn't a matter of saying, in effect, "Here's our heating/cooling elements; you, seat manufacturer, figure out how to make it work."

 

 

The ActiveCool is the newer of the systems. As its name implies, beyond just drawing the air away from the seated occupant, this system has two channels, one of which includes blowing cool air generated through the use of a thermal change insert (i.e., a Peltier device, a small ceramic-based solid-state unit that works as a heat pump) so that when the occupant gets into a hot car there is the sensation of cooling.

In the case of both systems, the main element is a "trim bag," which is tailored to the design of the seat and fitted between the foam and the outer fabric. (The bag approach was pioneered by W.E.T. when it developed its seat heating system.) This configuration, Brand says, is a distinct advantage to the W.E.T. approach versus competitors: "The installation is much easier." Fundamentally, there is the bag, a snap ring to attach to the blower, and the control unit. Other systems, he says, require ducting through the seat and channels in the foam to circulate the conditioned air. This approach can necessitate the use of different foam for those vehicles that don't have the heating/cooling option. What's more, he says, there is the potential of the foam with the ducts and channels to collapse. "Our system sits on top of the foam." So whether the option is for a heated seat or an active or passive climatized seat, the W.E.T. approach is essentially the same, so production complexity is minimized.–GSV

 

Sliding Load Floor

It's an idea that was borrowed from the Mercedes E-Class wagon, and one you can expect to see more of in the coming years: a load floor made of a rugged textured vinyl that slides over a pair of rails in the load area of a vehicle. In this case, the vehicle is the Dodge Nitro SUV concept. This construction allows the floor to be pulled over and just beyond the face of the rear bumper to ease loading and unloading. The sliding function can't be used if items are significantly over 150 lb. However, the extra reach is perfect for stowing and retrieving groceries and gear.

 

Common Touch

Although the way something feels is subjective, Renault has actually codified a reference frame for the tactile sense. This development has become available from a French company, Quinte&sens. It is called "Sensotact" (www.sensotact.com). Fundamentally, they've created a series of 10 descriptors and 50 references. These are standardized. The elements are housed in a suitcase. The tactile reference frame used includes subcategories for what are three primary aspects of the sense of touch: orthogonal (e.g., hardness); tangential (e.g., roughness), thermal. By codifying these attributes and by having standard references for them, it is said that users such as vehicle interior designers are able to more precisely achieve the feel that is being sought for a particular vehicle. Apparently, one of the drivers behind Renault's development of the tactile reference frame was the need to communicate with the company's colleagues at Nissan. The frame was used in the development of the Renault Modus minicar.