BRIAN JOHN WURTZ
Engineers in Levittown, PA
License number
Pennsylvania PE059505
Category
Engineers
Type
Professional Engineer
Address
Address
Levittown, PA 19055
Professional information
Dual Seal For A Vacuum Heat Treating Furnace
US Patent:
5709544, Jan 20, 1998
Filed:
Apr 16, 1996
Appl. No.:
8/639033
Inventors:
Brian J. Wurtz - Levittown PA
Assignee:
Abar Ipsen Industries, Inc. - Bensalem PA
International Classification:
F27D 118
US Classification:
432242
Abstract:
A vacuum heat treating furnace includes a pressure vessel having a wall that defines a chamber wherein metal parts are vacuum heat treated. A fan is disposed inside the chamber for circulating a cooling gas therein. An electric motor is mounted externally to the pressure vessel for driving the fan. A drive shaft interconnects the fan and the electric motor through an opening in the wall of the pressure vessel. The vacuum furnace incorporates a dual seal for providing a vacuum-tight seal and a gas-tight seal where the drive shafts passes through the pressure vessel wall. The dual seal includes an inflatable seal surrounding the drive shaft for providing a vacuum-tight seal around said drive shaft when the furnace chamber is evacuated to a subatmospheric pressure. The dual seal also includes one or more lip seals surrounding the drive shaft adjacent to said inflatable seal for providing a gas-tight seal around said drive shaft when the furnace chamber is backfilled with a superatmospheric pressure of the cooling gas and while the drive shaft is rotating.