【課題】 高出力かつ高信頼性の面状発熱体を提供する ことを目的とする。
【解決手段】 開口部を有するケース１２内に収納する とともにその一部をケース１２外に引き出した一対の熊 手状板バネ端子１３ａ，１３ｂと、この熊手状板バネ端 子１３ａ，１３ｂ上に設けるとともに、一方の主面に少 なくとも一対の櫛形電極１１ａを有するＰＴＣサーミス タ素子１１と、このＰＴＣサーミスタ素子１１上に設け るとともにケース１２の開口部を覆うように設けた放熱 板１４とを備えたものである。
PROBLEM TO BE SOLVED: To provide a planar heating element with its high output and high reliability by comprising at least one pair of rake shaped spring terminal partly induced to the outside of a case, a PTC thermister having at least one pair of comb-shaped electrodes at one main face, and a heat radiating plate provided so as to cover a case opening. SOLUTION: Two rake shaped plate spring terminals 13a and 13b are disposed inside of a case 12 so that part thereof is exposed to the outside of the case 12, and a PTC termister element 11 is disposed at the upper part. Then, an insulation plate 15 and a heat radiating plate 14 are disposed at the upper part of the PTC thermister element 11, and the heat radiating plate 14 is caulked with the case 12. Since power can be supplied to the PTC thermister element 11 without conductive adhesive by employing the rake-shaped plate spring terminals 13a and 13b, a heating temperature of the PTC thermister can be highly set. Since the PTC thermister element 11 is brought into closely adhered with the insulation plate 14 with a high spring pressure, high output can be obtained.