SEALING DEVICE FOR A GAS INLET TO AN OVEN OR THE LIKE

Abstract

A pipe for feeding a gas into an oven, a furnaces, or the like (such as a CVI/CVD oven), and in particular into a reaction chamber structure inside the oven, is provided with a gastight tubular sealing device extending radially outside the pipe and defining a path that is practically gastight, along which there extends the as feed pipe. The tubular sealing device is preferably at least partially flexible in the transverse direction and/or the axial direction so as to accommodate positioning defects between a location situated in the reaction chamber and a location where the gas feed pipe penetrates into the oven (which defects may be due, for example, to asymmetrical thermal expansion/contraction).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be better understood with reference to the accompanying figures, in which:

FIG. 1 is a diagrammatic cross-section view of an oven of the present invention, at the location where a reagent gas inlet pipe enters into the body of the oven and terminates in the vicinity of a gas inlet opening formed in a reaction chamber disposed in the body of the oven;

FIG. 2 is an exploded perspective view of the tubular sealing device of the present invention; and

FIG. 3 is a fragmentary view on a larger scale of a connection between first and second axial portions of the tubular sealing device of the invention.

Claims

1. A gas inlet device for causing a gas to pass into an oven from a portion external to the oven towards a gas inlet passage formed in a reaction chamber situated inside the oven, the inlet device comprising: a gas pipe for transporting a gas into the oven, the gas pipe extending between an outside portion of the oven and an inside portion of the oven, and having one end terminating at least in the vicinity of the gas inlet passage formed in the reaction chamber; anda tubular sealing device situated radially outwards relative to the gas pipe, the tubular sealing device being secured in gastight manner to a first end thereof, at a location of the inside surface of the oven adjacent to a location where the gas pipe penetrates into the oven, and extends towards a location adjacent to the gas inlet passage, being secured thereto in sealed manner;wherein the tubular sealing device comprises a first axial portion that is flexible and a second axial portion that is relatively rigid.

2. A gas inlet device according to claim 1, wherein the first axial portion has a bellows structure.

3. A gas inlet device according to claim 1, wherein the first axial portion is made of metal.

4. A gas inlet device according to claim 1, wherein the first axial portion is made of stainless steel.

5. A gas inlet device according to claim 1, wherein the second axial portion of the tubular sealing portion is made of metal.

6. A gas inlet device according to claim 1, wherein the second axial portion is made of Inconel.

7. A method of feeding a gas to a gas inlet passage of a susceptor in a reaction chamber, the method consisting in: placing a gas transport pipe putting an outside portion of the oven into communication with an inside portion thereof, the pipe terminating at least in the vicinity of the gas inlet passage; andsubstantially isolating the gas transport pipe by surrounding the gas transport pipe with a tubular sealing device that is practically gastight and that extends from an inside wall of the oven at the location where the pipe penetrates into the oven to a location adjacent to the gas inlet passage of the reaction chamber;wherein the tubular sealing device is secured in place in such a manner to form a part that is practically gastight through which the pipe extends, and wherein at least a portion of the tubular sealing device is flexible transversely to accommodate differences in position between the respective ends of the tubular sealing device at the locations where the sealing assembly is secured to the wall of the oven and is adjacent to the gas inlet passage.