Patent ID: 6737612
Filing Date: 2004-05-18
Classification: F23Q,H05B

Abstract:
A ceramic heater comprising:a rod-shaped heater body having an insulating ceramic substrate, a heating resistor embedded in a front end portion of the ceramic substrate and an electric conductor embedded in the ceramic substrate with a front end portion thereof electrically connected to the heating resistor and a rear end portion thereof exposed at a rear end surface of the heater body; and a lead-out member having a front surface joined to part of the rear end surface of the heater body via a metallic layer so as to cover the exposed rear end portion of the electric conductor and to be kept from covering an outer circumferential surface of the heater body, wherein the metallic layer is made of a brazing material, and wherein the lead-out member is formed into a plate and has a low-expansion metal layer at least in part of a rear surface thereof while keeping the front surface of the lead-out member in contact with the metallic layer, and the low-expansion metal layer is made of a metal having a lower coefficient of linear expansion than the brazing material for the metallic layer.