News

CASE HISTORY:
Designing with Glass — Get Bent

From Appliance Magazine, June 2001

Get Bent
For the past several years, fabricated glass and injection-molded plastic parts maker Gemtron Corporation, headquartered in Sweetwater, TN, has been inviting appliance OEMs to get bent - bent glass, that is. Company executives felt that cylindrically bent or curved glass could give numerous appliances a refined, modern look while allowing designers greater freedom to create less-conventional shapes. The problem: curved glass takes significantly longer to produce than flat varieties and may cost up to twice as much.

"Glass is a substrate that has been around forever. It's a mature and classy product, but it's more expensive than other substrates used for decorative purposes," says Brian Marchand, director of product development, Gemtron.

Undeterred by its higher cost, several European appliance makers have begun using curved glass in their latest models. To differentiate its high-end Jenn-Air wall ovens, Maytag Corporation (Newton, IA) wanted to be the first to introduce curved glass to the North American market.

Gemtron, one of Maytag's long-time suppliers, was selected to provide the glass after showing the appliance OEM several full-size mock-ups of oven doors featuring curved glass windows.

A strategic partnership with switch maker TouchSensor Technologies (TST) offered Gemtron another enviable advantage. Gemtron recognized that TST's patented electronic touch keypad, which works exceptionally well when glass is used as a substrate, would be an excellent way of promoting the creative use of glass in the appliance industry, the company became a shareholder in the Wheaton, IL-based company 2 years ago.

According to Mark Buss, vice president and general manager, cooking category, Maytag, the idea of using touch controls was appealing because the components would enhance cleanability while creating a modern, seamless look. "Jenn-Air's tag line is 'The Sign of a Great Cook.' Styling is very critical for the Jenn-Air brand. We want to be perceived as the leading innovator in both gourmet cooking performance and style."

Around the Bend
Gemtron, which has six facilities in North America, implemented into its Sweetwater, TN facility - a mere 30-min drive from Maytag's Cleveland, TN range plant - the ability to manufacture and assemble the electronic and glass panels to be closer to its customer.

The company decorates and bends two pieces of glass for each oven - one for the Panaview™ oven door window and one for the control panel. Both have radiused corners to minimize breakage and must be bent to the same 9-degree convex curve to ensure a proper match as well as a snug fit with the surrounding surfaces.

"The bend is critical," says Mr. Marchand. "The window employs what is called a 'free-floating' look, meaning there is no frame around it. When Maytag mounts this together, the tolerances have to be very tight to maintain a nice cylindrical look and to ensure everything fits flush."

The electronic touch keypads, manufactured by TST, use patented field-effect sensors which generate an electrodynamic field at the surface of the glass. Tom Schreiber, vice president, business development, explains that as a finger enters the field, it is recognized as human, and the switch is actuated. "The sensors are solid-state devices and therefore don't wear out like mechanical membrance or tactile switches," he adds.

The biggest challenge for TST, explains Mr. Schreiber, was achieving the curvature of the electronics. "The printed circuit board containing our electronics had to be bent to match the contours of the glass," he says. "The Maytag and TST engineers determined this to be a critical design factor at the project kick-off meeting. Prototypes were under test within 4 weeks so we were able to verify the robustness of design at the first phase of the project."

While the industry has sought to use touch controls more extensively for years, these components have been too costly to implement in the past, explains Mark Delp, senior vice president, sales and marketing, Gemtron. "It's been cost-prohibitive because to have [such controls] on glass in the past, a conductive trace was required to conduct current. We would have to screen print these big, thick pads on the front of the glass. When the operator touched the pad, it would activate the switch or control to which it was attached."

Mr. Delp continues: "The other way [to achieve a similar operation] was a conductive coating, generally tin oxide, which would have to be selectively coated on the glass. That was very expensive from a glass and decoration standpoint. TST allowed us to simply attach their system on the back of our glass without any special details or decoration."

TST ships the controls to Gemtron's Sweetwater facility, where they are applied to the back of the control panel and tested. The assembled control panel and curved glass window are then sent to Maytag, where they are simply "assembled into the range," says Mr. Marchand.

A 'Win-Win' Situation
Thanks to careful planning and communication between Maytag, Gemtron, and TST, the Jenn-Air Curved Glass Wall Oven, which made its debut in January 1999, at the International Homebuilders' Show in Dallas, was ready for production in only 15 months - considerably shorter than the 18-24 months Maytag says generally are required to develop a cooking product of similar complexity.

The project was labeled as a "dream project." Gemtron's Mr. Marchand explains further: "The electronics and assembly of the electronics went without a glitch; the actual bending went without a glitch; and the look went without a glitch. There were some revisions to the bend, but no major problems."

In addition, he adds, "Everyone involved did their homework 16 months in advance. Maytag worked with a supplier prior to the product being made to develop the tolerances; so when the final blueprints came for the appliance's production, both had done the design up front. Everyone talks that way; but it's unusual that it actually happens to this extent."
Not only is the oven the only curved glass wall oven available in North America, but Maytag says it is the only self-cleaning, curved glass oven on the market, including Europe.

"This is one of the few opportunities I have witnessed where the customer [Maytag] sat down with us before drawings were derived and asked what our capabilities were and asked how they should approach the project," says Mr. Delp.

The project proved to be a 'win-win' situation for all involved. In addition to the benefits associated with being first to market, Maytag comes out ahead because the upscale new look and touch sensor technology allowed the company to increase the retail price of its Jenn-Air wall ovens, says Mr. Buss.

Gemtron and TST, in turn, received greater exposure for its curved glass and touch keypads respectively. In addition, the company became more of a system supplier and not just a glass supplier. "We supply the curved oven door and the curved control panel; apply the electronics to the back of the panel; and assemble, market, and sell it as a package."

What's more, adds Mr. Marchand, the innovation has caused many designers to "look at other product lines that historically never used glass to see if the combination of glass and electronics might go well with other white goods. That's totally amazing to me," he says, "and it opens a huge marketplace for us. Maytag's introduction of the bent glass panel has got everyone scurrying to look and see what they can have."

Maytag's Jenn-Air curved glass wall ovens offer a well-rounded solution for consumers who enjoy the cooking process and desire striking aesthetics.

"Now, cost doesn't seem to be the major driver; product distinction, product look, and product value seems to be making a comeback into the appliance market," adds Mr. Marchand.

A comeback that is much welcomed.

> Return to News Page