Intake heating apparatus of an internal combustion engine

摘要

An intake heating apparatus of an internal combustion engine, comprising a hollow heater vessel which is placed in an intake passage of the engine and which comprises an inner pipe, an outer pipe in which said inner pipe is press-fitted, peripherally spaced PTC elements located between the inner and outer pipes, and an annular elastic electrode located between the PTC elements and the outer pipe. The improvement comprises means for preventing the PTC elements from being broken when and after the inner pipe is press-fitted in the outer pipe.