| 摘要 |
PROBLEM TO BE SOLVED: To overcome the following problems of conventional columnar type ceramic heaters: a conventional heater is inadequate in dimensional stability because of its periphery made of ceramic, which consequently worsens the heat transmission to an object to be heated; and a conventional one is fragile to a thermal shock because of being made of ceramic; as to the means for using a whole glass ceramic body enclosed in a metal cylinder, which was devised as a solution to the above problems, there is still the impossibility of putting the glass ceramic body and the metal cylinder in absolute contact with each other; and a metal powder may be filled between the glass ceramic body and the metal cylinder to achieve such absolute contact for better heat transmission but, it is difficult to achieve such absolutely filling and the heat transmission still remains insufficient.SOLUTION: A heater comprises: a ceramic heater; a metal cylindrical body which contains the ceramic heater and opens at one end thereof; and metal powder filled between the ceramic heater and the metal cylindrical body. The outer diameter of the metal cylindrical body is smaller by 5-15% in comparison to that before containing the ceramic heater; and the opening is closed by an inorganic material.SELECTED DRAWING: Figure 1 |
