4058787 A abstract a drawer type electrode of a thermistor for sensing high temperatures wherein a shaft and a sheath are connected to a thermistor is constructed such that the shaft and the sheath are brought into contact with the positive and negative electrode surfaces of the thermistor through precious metal chips so that electrical connection between the precious metals the shaft and the sheath will not be impaired in any way even if oxidation penetrates into the interior from the shaft and the sheath surface due to high temperature application_number US 66970276 A description the temperature sensor shown in fig1 is for example used for giving an alarm in case the temperature within a catalytic converter for use in an automobile exceeds the preset value for the protection of the converter the negative electrode surface 1a of a thermistor 1 is brought into contact with a precious metal such as a platinum chip 3a which is welded to the interior of a cylindrical sheath 2 made of an electrically conductive and heat resistant metal further the sheath 2 is solidly secured to an electrically conductive plug body 4 a grounding conductor 5 is a belt like thin metallic plate which is highly heat resistant and is secured to the plug body 4 by spot welding the positive electrode surface 1b of the thermistor 1 is brought into contact with an end face of a shaft 6 made of a heat.