Holder driving unit
Patent 6805487 Issued on October 19, 2004. Estimated Expiration Date: 
October 17, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
October 17, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesFluid pressure seal arrangement Rotatable seal assembly Linear gas bearing with integral vacuum seal for use in serial process ion implantation equipment Static pressure bearing Manipulator for vacuum applications Method and apparatus for continuous throughput in a vacuum environment Patent #: 4812101 InventorsAssigneeApplicationNo. 08953638 filed on 10/17/1997US Classes:384/16, Annular277/431, Formed by pressurized sealing fluid introduced to form barrier277/913, SEAL FOR FLUID PRESSURE BELOW ATMOSPHERIC (E.G., VACUUM, ETC.)384/12Fluid bearingExaminersPrimary: Hannon, Thomas R.Attorney, Agent or FirmForeign Patent References
International ClassesF16C 3372F16J 1540 AbstractA holder driving device has: a holder holding a substrate, a shaft supporting the holder, a driver for driving the shaft reciprocatingly and linearly in the direction along the shaft, a bearing unit having mechanical linear motion bearings for supporting the shaft thereon and having one or more stages of exhaust chambers surrounding the shaft; a vacuum pump for vacuum-pumping the exhaust chambers of the bearing unit; and a gas replacement mechanism for supplying dry gas, the humidity of which is lower than that of at least the surrounding atmosphere and the pressure of which is positive, from the outside of the bearing unit to at least the neighborhood of an atmosphere-side entrance portion of a gap between an end portion of the bearing unit one the side opposite to the vacuum vessel and the shaft passing the end portion, so as to replace the atmosphere near the entrance portion by the dry gas. | |
