Electric blanket

Heating pads and electric blankets, heat donors, electrically operated, enabling a continuous, tight-fitting heat. Heating pads are used by heat needy people and animals in order to protect themselves from the cold or to warm the bed. A further application is the heat treatment of chronic pain.

History

The first heating pads and electric blankets already arrived in the late 19th and early 20th century with the beginning of the supply of the population with electric energy. They replaced the operated with glowing coal bed pans and heat in the oven to be heated heat stones almost completely, but could not dislodge the emerging in the 1920s, hot water bottles made ​​of rubber.

Function and nature

Unlike heating pads that give off a chemical reaction temporarily heat, heating pads and electric blankets are heated by an electric heater. In the electric devices, heating wires are ( resistance wires ), which convert the electrical current supplied to heat. The need for heating power is comparatively small and is only about 60W with heating pads and approximately 100 - 200W with electric blankets. Already in older devices enabled tap changer to operate different sets of parallel heating wires and thus to control the size of the heat supply. Modern heating pads and blankets have an electronic temperature control and automatic shut-off to prevent overheating. Characterized a largely unattended operation is possible, such as during sleep.

Most devices are operated directly from the mains with an AC voltage of 230 volts and at the same time close to directly on the human body. Therefore, high demands are placed on safety. So is the wrapping of the heating wires, at the same time desired flexibility should be vandal resistant and waterproof insulated. The only way to ensure that when in contact with body fluids, such as during heavy sweating, urinary and fecal incontinence or spills electrical accidents can be avoided.