US 2003/0116894 A1 · Multi-cell thermal processing unit

Abstract

The present invention relates to a multi cell thermal processing unit. The thermal processing unit comprises an air tight common chamber containing an atmosphere other than ambient air. A loading cell is linked to the common chamber via a gas tight door for providing to and receiving from the common chamber a workpiece. Further, a preheating cell is linked to the common chamber via a heat insulating door. The preheating cell provides a substantially fixed temperature for activating the workpiece. Thermochemical processing of the workpiece is provided by a first and a second thermochemical processing cell each linked to the common chamber via a heat insulating door. The first thermochemical processing cell provides substantially fixed first thermochemical processing conditions for nitriding the workpiece. The second thermochemical processing cell provides substantially fixed second thermochemical processing conditions for post nitriding treatment of the workpiece. A cooling cell linked to the common chamber provides controlled cooling of the workpiece. The thermal processing unit according to the invention, wherein thermochemical processing cells are operated under substantially constant conditions considerably facilitates control functions for providing predetermined conditions. This allows a substantially more accurate control of the thermochemical processing conditions which is especially advantageous for reproducibly thermochemical processing workpieces using nitriding processes.

Claims31

Dependent claims

A multi cell thermal processing unit comprising:

an air tight expandable common chamber module for containing an atmosphere other than ambient air, the chamber module comprising N ports;
a loading cell linked to the first port of the common chamber module via a gas tight door for providing to and receiving from the common chamber module a first and a second workpiece;
a first thermochemical processing cell linked to the second port of the common chamber module via a heat insulating door, the first thermochemical processing cell for providing substantially fixed first thermochemical processing conditions for thermochemical processing the first workpiece;
a second thermochemical processing cell linked to the third port of the common chamber module via a heat insulating door, the second thermochemical processing cell for providing substantially fixed second thermochemical processing conditions for thermochemical processing the second workpiece;
a transport mechanism disposed within the common chamber module for handling and transporting the first and the second workpiece within the thermal processing unit;
and,
N-3 sealing covers for airtightly sealing the remaining N-3 ports, the covers being removable for mating the common chamber module to a processing cell or another common chamber module.

4 more elements

A multi cell thermal processing unit comprising:

an air tight common chamber for containing an atmosphere other than ambient air;
a loading cell linked to the common chamber via a gas tight door for providing to and receiving from the common chamber a first and a second workpiece;
a preheating cell linked to the common chamber via a heat insulating door, the preheating cell for providing a substantially fixed temperature for activating the workpiece;
a first thermochemical processing cell linked to the common chamber via a heat insulating door, the first thermochemical processing cell for providing substantially fixed first thermochemical processing conditions for thermochemical processing the first workpiece;
a second thermochemical processing cell linked to the common chamber via a heat insulating door, the second thermochemical processing cell for providing substantially fixed second thermochemical processing conditions for thermochemical processing the second workpiece;
and,
a transport mechanism disposed within the common chamber for handling and transporting the first and the second workpiece within the thermal processing unit.

4 more elements

A method for thermal processing a workpiece comprising the steps of:

providing a first workpiece to a first thermochemical processing cell linked to a common chamber containing an atmosphere other than ambient air;
thermochemical processing the first workpiece by providing a first portion of thermochemical processing conditions of a first thermochemical process;
transferring via the common chamber the first workpiece from the first thermochemical processing cell to a second thermochemical processing cell linked to the common chamber after elapse of a first predetermined time interval;
thermochemical processing the first workpiece by providing a second portion of the thermochemical processing conditions of the first thermochemical processing process;
and, removing the first workpiece from the second thermochemical processing cell after elapse of a second predetermined time interval.

2 more elements

Dependencies are inferred from the claim text.

Multi-cell thermal processing unit

Life of this patent

Multi-cell thermal processing unit

Life of this patent

Abstract

Claims31