X-Ray apparatus and closure mechanism therefor

An apparatus for inspecting various articles comprising

• a chamber defining structure including enclosing walls and a retractable door, said structure being substantially impermeable to X-rays,
• a shaft member inside said structure and provided for carrying said retractable door, said retractable door including a flexible construction windable on said shaft member, wherein winding said flexible construction onto said shaft member opens said chamber and unwinding said flexible construction from said shaft member closes said chamber,
• motor means for driving said shaft member in rotation,
• a gear train mechanically linking said motor means and said shaft member, said gear train including a drive gear driven by said motor means and having gear teeth only about a portion of its circumference, and a driven gear connected to said shaft member and having gear teeth only about a portion of its circumference,
• said driven gear being moved independently of said drive gear upon closing said chamber, and said drive gear engaging said driven gear upon opening said chamber, and
• switch means actuated by said drive gear for controlling said motor means.