The engineer's role in transforming the domestic environment throughout the century has been enormous. It began with electrification, which brought light and power into homes. The household appliances that followed in the first half of the century depended on two basic engineering innovations - resistance heating and small, efficient motors. These technologies were incorporated into devices ranging from electric stoves and heaters to vacuum cleaners and dishwashers. In the second half of the century new technologies like the magnetron and microprocessor transformed the household environment yet again, spawning new appliances with sensors, timers, and programming devices. Always, design innovations focused on making appliances lighter, smaller, more energy efficient, and more useful.
Until these products arrived, most women organized household work by day. Families were generally large, and chores took a long time. One day was set aside for laundry. The tools at hand were wash boards and tubs, boilers, and clothes lines. Another day was for ironing and sewing. Heating heavy flat irons on the stove, keeping two or three going at the same time so there was always a hot one, keeping the fire stoked with coal or wood. Cutting cloth and stitching it by hand. Making one's own patterns for dresses and shirts. Another day was for cleaning -- sweeping with brooms, scrubbing and waxing floors by hand, taking rugs to the clothes line to beat the dust and dirt away. One day was set aside for baking, canning and preserving.
By contrast, the modern family may program the coffee-maker before going to bed at night so it turns on when the alarm goes off in the morning. Refrigeration, freezers, blenders, waffle makers, food processors, bread machines, and other kitchen appliances make breakfast preparation a chore that takes minutes instead of hours. Automatic washers and dryers allow one to do the laundry and clean the house at the same time. Machines to shampoo carpets, wax and polish floors, and steam clean upholstery are easy to operate and efficient, cutting labor time from a long day to a short few hours.
One of the first appliances to help end hours of drudgery was the vacuum cleaner. James W. Spangler received the first U.S. patent for an electric vacuum cleaner in 1908. Early models were clumsy and difficult to maneuver. The first Hoovers weighed 40 pounds, most of it the weight of motor. In 1909 a small, high-speed universal motor was developed that greatly reduced the weight.
Early clothes washers appeared in the mid 1920s and were wringer types that were hand-cranked and had a foot pump to start the motor. By 1953 automatics were outselling wringer washers 10 to one. Innovations have resulted in modern machines that offer cycles for different types of garments, water temperature and level options. The first dryer manufactured by a company weighed 700 pounds. Realizing the model would be impossible to install in homes, engineers returned to the drawing board and designed a 200-pound model.
The electric toaster was a small, but important device to many. Numerous attempts to find the proper heating element were tried by dozens of engineers and inventors, including Thomas Edison. Finally, in 1905 an engineer solved the problem. Albert Marsh received a patent on an alloy of nickel and chromium, Nichrome. Dozens of designs for electric toasters followed within two months.
Percy L. Spencer, an electrical engineer, developed the microwave oven in the 1940s. While touring a laboratory at the Raytheon Company, he stopped momentarily in front of a magnetron, the power tube that drives a radar set. Spencer noticed that the chocolate bar in his pocket had begun to melt. He immediately experimented with a bag of unpopped corn, holding it next to the magnetron. His quick observation powers and this simple experiment led to his development of the microwave oven.
A major event that contributed to the success of electrical appliances was the standardization of electric outlets and plugs in the 1920s. Early versions of many appliances had wiring with plugs that screwed into an overhead light or a wall sconce - wall outlets did not appear until much later. Revisions to the National Electric Code and National Housing Code encouraged the installation of high capacity wiring and multitudes of wall outlets in new houses, providing further safety for families. Safety standards for appliances were outlined by the Underwriters Laboratories, Inc., to ensure that appliances sold to consumers minimized the risk of fire and electric shock.
For women in the last half of the century, the domestic engineering revolution began to include digital technology. For the majority of women in the workforce, having the added convenience of timing and programming devices helped to maintain high standards in caring for the family. This technology also made it easier to delegate chores among family members - more young children know things about a microwave oven than many of their grandparents.
Household appliances give us more free time, and their related industries contribute significantly to our economy. Their impact on life in the 20th century has been immense.
