441 Chandler Street, Jamestown, NY 14701
Weber Knapp

Case Study: Concealed Hinges for the Hidden Fridge

The kitchen has achieved unprecedented status in today’s homes. As the modern-day hub for family interaction and entertaining, its new generation of high-end appliances has taken center stage, merging high style with performance. While one popular design trend calls attention to distinctive appliance design, another growing trend utilizes wood-paneled doors that blend into kitchen cabinetry to make appliances as inconspicuous as possible.

Recently, the design collaboration between OEM and supplier continued when the refrigerator maker issued Weber-Knapp another challenge. For its new 700 Series, which was unveiled at the Kitchen & Bath Show earlier this year, Sub-Zero developed a 36-in. wide full-size refrigerator unit with two freezer drawers below it. This meant that the new hinge would have to support a 36-in. door weighing 143 lbs. Weber-Knapp accomplished the mission, producing a concealed hinge that handled the extra duty, while resisting door sag and still functions within parameters after 300,000 test cycles double the number expected in a typical refrigerator door’s lifespan.

The stealthy appliance trend was boosted by high-end refrigerator maker Sub-Zero, Madison, Wis., and was made possible in part by a concealed hinge designed by Weber-Knapp, Jamestown, N.Y., a designer of custom hinges and other products.  Weber-Knapp was approached in 1988 by Sub-Zero after the appliance maker was dissatisfied with the concealed hinge designed for them by a large Midwestern University.

The challenge was to produce a concealed hinge that was no more than 3/4-in. high yet would support a 107-lb. door with its shelves and bins loaded. None of the hinge could protrude or even be visible when the door was closed. The Weber-Knapp hinge design proved successful and helped spawn a trend that continues to grow.

Both hinge versions, the original and the new one, allow flexibility in kitchen layout. For example, the standard full-open position swings the door 105 . But that can be easily changed in the field to accommodate kitchen designs in which a 90 angle is the maximum the space allows, protecting adjacent walls or other cabinetry from door impacts. Adding to functionality is the self-closing feature, which creates a bias toward the closed position over a 30 angle. The hinge design features a four-bar linkage system adapted to support the door’s width, weight and the frequency of use. Design parameters can be adjusted to meet specific product configurations.

Reprinted with permission from an article written by Richard Babyak and published in an issue of Appliance Design – November 2004