When was the electric blanket invented?

ade, a British Bai, invented the electric blanket around February 1948. It has a history of more than 100 years.
It is a kind of contact type electric heating appliance. 

It weaves or sews the special soft cable electric heating element into the blanket in the form of a coil snake, 
which emits heat when it is electrified. 

Besides,the warm blanket, electric mattress 
and electric pad,their working principle and structure are similar to the electric blanket

.
It is mainly used to raise the temperature in the quilt when people sleep to achieve the purpose
 of heating. It can also be used for dehumidification of bedding. 

It has the advantages of low power consumption, adjustable temperature, convenient use and wide use.