John L Webb

US Patent:

39727041, Aug 3, 1976

Filed:

Aug 5, 1974

Appl. No.:

5/495129

Inventors:

Ted A. Loxley - Mentor OH
Walter G. Barber - North Perry OH
Walter W. Combs - Mentor OH
John M. Webb - Chagrin Falls OH

Assignee:

Sherwood Refractories, Inc. - East Cleveland OH

International Classification:

C03B 2900

US Classification:

65157

Abstract:

Apparatus is disclosed for automated mass production of precision transparent silica glass products in accordance with a unique process in which slip-cast fused silica articles are rapidly heated and sintered in a vacuum or in a helium or hydrogen atmosphere at high temperatures, such as 2950. degree. to 3150. degree. F. A heated graphite susceptor shaped to conform to the outer surface of the fused silica article is automatically moved between a cooling zone and an induction furnace chamber which is opened momentarily to admit the article. The furnace and the graphite susceptor are designed to cause the trapped gases in the article to move radially outwardly and to effect rapid heating so as to avoid substantial devitrification during sintering.

US Patent:

40724891, Feb 7, 1978

Filed:

May 10, 1976

Appl. No.:

5/684730

Inventors:

Ted A. Loxley - Mentor OH
Walter G. Barber - Mentor OH
Walter W. Combs - Mentor OH
John M. Webb - Chagrin Falls OH

Assignee:

Sherwood Refractories, Inc. - Cleveland OH

International Classification:

C03B 2320
C03B 3200

US Classification:

65 18

Abstract:

A process is disclosed for making vitreous silica crucibles of exceptional high quality for use in the growing of a silicon crystal from molten silicon. The crucibles are formed from fine particles of high purity fused silica by slip casting or other suitable process, are dried and fired to provide a rigid porous body, and are thereafter sintered to a high density, preferably to the transparent state. The invention solves the problem of spalling, blistering and cracking during crystal growing and the resulting contamination of the molten silicon, which has long plagued the industry, by eliminating water from the fused silica particles before the porous body is sintered to the transparent state. Said body is thoroughly dried in a vacuum furnace at a high temperature and at a sub-atmospheric pressure low enough to remove the chemically bound water which cannot be removed by heat alone. The crucibles of this invention retain their transparency and high quality without spalling or introducing microscopic particles of silica into the silicon, thereby making it possible to grow a silicon crystal of highest quality without dislocations and imperfections due to contamination by said particles.

Address:

24925 Shaker Blvd, Beachwood, OH 44122

Phone:

2167650634

VIN:

JNKBV61F57M802982

Make:

INFINITI

Model:

G35

Year:

2007