Patent ID: 6491178
Filing Date: 2002-12-10
Classification: H01L

Abstract:
An upper cover plate for an air-tight chamber, for engaging a chamber body to form the air-tight chamber, the chamber body including a top surface for matching with a bottom surface of the upper cover plate, further including a plurality of thread holes engageable respectively with a plurality of tools, and characterized in that: at least one of the plurality of thread holes is formed as a through thread hole connecting to the bottom surface, and the respective tool for engaging with the through thread hole includes a portion thereof for penetrating the through thread hole and going beyond the bottom surface, wherein said tool for engaging with said through thread hole includes:a hand bar, for receiving a torque to drive said tool helically along said through thread hole; a stem bar, formed as a rotation axis for the hand bar, having thereof a first end connecting fixedly with the hand bar; and a thread part, fixedly connecting with a second end of the stem bar, engageable with said through thread hole; wherein while said tool is being applied to said through thread hole, the torque is applied to the hand bar to rotate the thread part feeding along said through thread hole until a portion of the thread part goes beyond said bottom surface of said upper cover plate, wherein said thread part further includes an extended portion for going beyond said bottom surface of said upper cover plate, said extended portion further including a friction sleeve wrapping an exterior thereof.