Patent dates don't have anything to do with
manufacture date. Some people don't realize that patents aren't
like copyrights. When you publish a book, the copyright date is
the year in which it was written. If you update the book and publish a
second edition, the copyright will often include both years or a range
of years.
When you are issued a patent for an invention,
the patent is good for many years and never changes. The Sunbeam Radiant
Control toasters contain a number of patented inventions but none later
than the 50's. Even though the toaster was manufactured in the 1990's,
it doesn't necessarily need to get a new patent number issued in the
1990's. If it uses only "old" patents, then that's all it
needs to list.
Polarized plugs were introduced in the US sometime in
the mid-1960's as far as I can tell. Appliances use polarized plugs when
it is necessary for the appliance to be plugged in a certain way in
order to function correctly, or in order to be safe. If an appliance
doesn't need to be plugged in a certain way, it need not have a
polarized plug. So the absence of a polarized plug doesn't mean your
toaster was manufactured in the 1950's.
Labeling is inconsistent across the life of the
product line. The early T-20 models had a manufacturing date stamped
inside the toaster. This practice only lasted a few years. Later models
do not have manufacture dates anywhere on them.
The box is the only place you'll find the real
model number. Starting in the 1970's, Sunbeam stamped "Service
AT-W" on the bottom of all the Radiant Control toasters, regardless
of what the model number was on the box or in the catalog. So the box
might say 20-30, 20300, or even AT-35A but the toaster just says AT-W.
The design of the darkness control could be markedly different between a
toaster made in 1975 and one made in 1985, but they both just say AT-W
on the bottom. Sometimes, the picture on the box didn't match the exact
design of the toaster inside.
When you don't have a box, it's impossible to know what
model number your toaster was sold as. Even if you do have a box, you
can't tell the date of manufacture unless the distributor or retailer
happened to stamp a date on it. The best way to know when a toaster was
sold is if the person who bought it knows when they bought it. Much of
the information here is derived from these firsthand accounts.
Models and Dates
The table below tells you how to identify a particular
model and approximately when it was manufactured based on our research.