Patent ID: 7692118

Claim:
A glow plug comprising: a center pole extending along an axial direction; a heater including a heating element, said heater being connected to a leading end portion of the center pole; a metal shell which has an axial hole extending in the axial direction, the center pole being inserted into the axial hole so as to be spaced apart from an inner peripheral surface of the axial hole, the metal shell radially holding a rear end portion of the center pole directly or indirectly while causing the rear end portion of the center pole to project from a rear end portion of the metal shell, the metal shell at its leading end portion radially holding directly or indirectly the heater; and a vibration preventing member for preventing vibration of the center pole, the vibration preventing member being fixed on an outer peripheral surface of the center pole at an axial position corresponding to a portion where an inside diameter of the axial hole of the metal shell is constant.