Patent ID: 8330120

Claim:
An electron beam sterilizer provided with electron beam irradiating means ( 28 ) that irradiates electron beam through an irradiation window ( 46 ) and vessel conveying means ( 24 ) that conveys a vessel ( 2 ) passing in front of the irradiation window ( 46 ), in which the vessel ( 2 ) is sterilized by irradiating the vessel ( 2 ) with the electron beam emitted from the electron beam irradiating means ( 28 ), characterized in that the irradiation window ( 46 ) has a length in the vessel conveying direction (X) larger than a vessel moving distance during an electron beam irradiation interruption time caused by generation of a spark by the electron beam irradiating means ( 28 ), the electron beam irradiation means ( 28 ) is arranged to output a detection signal when the spark is generated and the detection signal is input from the electron beam irradiation means to a controller, the controller recognizes a pulse of an encoder of the vessel conveying means ( 24 ) and specifies the vessel in question which passes in front of the irradiation window while the electron beam irradiation is interrupted so as to reject the vessel at a given reject position and the irradiation window has a length in the vessel conveying direction (X) larger than a vessel moving distance during an electron beam irradiation interruption time caused by generation of a spark by the electron beam irradiating means ( 28 ) so as to allow the rejected vessel to be subject to the electron beam irradiation.