Furnace for heat treatment of dental materials

• US 6,252,202 B1
• Filed: 02/04/1999
• Issued: 06/26/2001
• Est. Priority Date: 02/10/1998
• Status: Expired due to Fees

• Current Assignee: Jeneric/Pentron Incorporated (Danaher Corporation)
• Original Assignee: Jeneric/Pentron Incorporated (Danaher Corporation)
• Inventors: Zychek, George N.
• Primary Examiner(s): Jeffery, John A.
• Application Number:
  US09/243,985
• Time in Patent Office: 873 Days
• Field of Search: A61/C 1.320, F27/B 1.702, 219/390, 219/391, 219/420, 219/424, 219/476-480, 219/388, 219/541, 219/521, 219/385, 126/343.54, 164/34, 164/35, 164/246, 164/376, 264/16, 264/17, 264/19, 433/25, 433/32, 433/213, 432/229, 432/239, 432/241, 432/121, 432/253, 432/258, 432/135, 392/418, 373/115, 373/109, 373/112, 414/147, 414/153, 414/154, 414/172
• US Class Current: 219/390
• CPC Class Codes: A61C 13/20 Methods or devices for soldering, casting, moulding or melting A61C13/04, A61C13/081 take precedence
• CPC Class Codes: F27B 17/025 for dental workpieces

Abstract

A furnace is provided generally including an upper heating chamber and a lower work base or firing platform. The upper chamber provides the main source of heat to the materials to be heat-treated. The upper chamber contains a muffle within which is located a heater ring assembly. The heater ring assembly is located in the middle to upper half of the muffle and includes an annular heating element that is located between an outer insulation ring and an inner quartz sleeve. A cavity or channel extends through the muffle into which insulation materials and the heater ring assembly is located. The channel area in the muffle below the heater ring assembly allows for the placement of the firing platform therein. The firing platform includes insulation material and a heating element located in the upper portion thereof. The heating element located in the firing platform provides heat to the firing platform such that when the firing platform is positioned within the muffle channel, heat is more evenly distributed throughout the heating area.

Claims

1. A furnace for heating a dental material comprising:

an upper chamber having an upper heating element therein; and

a movable work base having a lower heating element therein;

a linear rail;

a movable bracket coupled to the linear rail and movable vertically along the rail;

a platform bar coupled to the bracket;

a work base plate disposed on the platform bar for holding the work base;

a linear conductor assembly; and

a brush holder assembly coupled to the platform bar, movable in the vertical direction, in contact with the linear conductor assembly, and linked to the heating elements.

2. The furnace of claim 1 wherein the linear conductor assembly comprises:

a mounting bar;

a series of insulator blocks mounted to the mounting bar; and

a series of conductor rods mounted between the insulator blocks.

3. The furnace of claim 2 wherein the brush holder assembly comprises:

a series of spring loaded brushes, which maintain contact with the conductor rods.

4. The furnace of claim 1 wherein the dental material is selected from a facing, a veneer, a bridge, an inlay, or a crown.

5. The furnace of claim 1 wherein the upper chamber includes a second upper heating element located above the first upper heating element.

6. The furnace of claim 5 wherein the second upper heating element located above the first upper heating element comprises a single spiral unit positioned over and above the firing platform.

7. The furnace of claim 1 further comprising a vacuum atmosphere.

8. The furnace of claim 1 further comprising a cap positioned on the work base wherein the heating element is positioned substantially parallel to the top of the workbase.

9. The furnace of claim 1 further comprising a cap positioned on the work base wherein the heating element is positioned substantially parallel to the cap.