US Patent 7723651 Heating pad

A heating pad is disclosed. The heating pad has a heating line received in a bag, wherein a plurality of heat preservation elements are slipped over the heating line; when the heating pad is electrified, a controller controls the temperature of the heating line for heat applying on a human body; when a electric source is turned off, the heating line stops being heated up, the heat preservation elements keeps on scattering heat outwards to extend the time of heat applying. The heat preservation elements can be ceramic pipes able to emit far infrared ray, so that during heat applying, the ceramic pipes can emit far infrared ray to get an effect of health care.