Dental furnace as well as method for operating a dental furnace

Patent metadata

Field	Value
Publication number	US-10955192-B2
Application number	US-201816128672-A
Country	US
Kind code	B2
Filing date	Sep 12, 2018
Priority date	Sep 18, 2017
Publication date	Mar 23, 2021
Grant date	Mar 23, 2021

Abstract

A dental furnace having closed or closeable firing chamber ( 12 ), which is surrounded by thermal insulation ( 20 ) and which comprises at least one inlet terminal ( 22 ) and at least one outlet terminal ( 24 ). Via said two terminals, a gas, especially air, may be passed through the firing chamber ( 12 ) and/or may be discharged from the firing chamber ( 12 ), wherein a vacuum source ( 44 ) is provided, which is in direct or indirect communication with the outlet terminal ( 24 ) and via which the outlet terminal ( 24 ) may be set under vacuum pressure. At the outlet terminal ( 24 ), an especially T-shaped or Y-shaped connector ( 26 ) is attached. The connector ( 26 ) comprises two entrance ports ( 32, 24 ) and an exit ( 40 ), wherein the exit ( 40 ) is in communication with the vacuum source ( 44 ) and a first entrance port is in communication with the firing chamber ( 12 ), and especially is flange-mounted at the outlet terminal ( 24 ) thereof, and a second entrance port ( 34 ) is in communication with ambient air.

First claim

The invention claimed is:

1. A dental furnace comprising a closed or closable firing chamber, which is surrounded by thermal insulation,
at least one inlet terminal and at least one outlet terminal, through both of which a gas is passed through the firing chamber and/or us evacuated through the firing chamber,
a vacuum source in direct or indirect communication with the at least one outlet terminal and by which the at least one outlet terminal is depressurized,
wherein at the at least one outlet terminal a T-shaped or Y-shaped connecter is directly attached, wherein the connector comprises two entrance ports and one exit wherein the exit is in communication which the vacuum source, and a first entrance port is in communication with the firing chamber and a second entrance port is in communication with the ambient air.

2. The dental furnace according to claim 1 ,
wherein the gas comprises air and the first entrance port is flange-mounted to the at least one outlet terminal.

3. The dental furnace according to claim 1 ,
wherein the second entrance port of the connector is connected to a first air line having a flow resistor.

4. The dental furnace according to claim 3 ,
wherein the flow resistor comprises a valve.

5. The dental furnace according to claim 1 ,
wherein the at least one inlet terminal and the at least one outlet terminal are arranged opposite to each other on the firing chamber of the dental furnace, such that at least one part of the firing chamber extends there between.

6. The dental furnace according to claim 3 ,
wherein the at least one inlet terminal is connected to a second air line which comprises a valve and/or a filter.

7. The dental furnace according to claim 3 ,
wherein a suction line extends between the connector and the vacuum source, enabling heat exchange between the ambient air of the first air line and the aspirated air passing through the suction line due to the material used for the suction line.

8. The dental furnace according to claim 7 ,
wherein the suction line comprises a heat exchanger, which is also connected to the first air line of the entrance port of the dental furnace.

9. The dental furnace according to claim 8 ,
wherein the heat exchanger is provided with a bypass line located on the suction line, which bypass line is provided with a switching valve.

10. The dental furnace according to claim 1 ,
wherein the connector is fabricated of a thermally conductive material, and
wherein the connector near the second entrance port is provided with a connecting piece predetermined length.

11. The dental furnace according to claim 10 ,
wherein the thermally conductive material comprises metal, and
wherein the predetermined length equals 10 cm in length.

12. The dental furnace according to claim 10 ,
wherein the connector comprises cooling ribs.

13. The dental furnace according to claim 1 ,
wherein the fresh air line supplying fresh air to the second entrance port of the connector, is connected to external heat sources of the dental furnace and
wherein the fresh air supplied cooling air to the external heat sources for cooling and evacuation of hot air.

14. The dental furnace according to claim 13 ,
wherein the external heat sources of the dental furnace comprise power electronics.

15. The dental furnace according to claim 1 ,
wherein at least two inlet terminals for supplying fresh air to the firing chamber are provided, which are arranged spaced apart from each other and are located opposite of the at least one outlet terminal.

16. A method for operating a dental furnace,
the method comprising
providing the dental furnace
wherein the dental furnace comprises
a closed or closable firing chamber, which is surrounded by a thermal insulation,
at least one inlet terminal and at least one outlet terminal, through both of which a gas is passed through the firing chamber and/or is discharged through the firing chamber,
a vacuum source in direct or indirect communication with the outlet terminal and by which the outlet terminal is depressurized,
wherein at the at least one outlet terminal a T-shaped or Y-shaped connector is directly attached, wherein the connector comprises two entrance ports, and a first entrance is in communication with the firing chamber and a second entrance port is in communication with ambient air,

evacuating gas from the firing chamber using vacuum pressure via the at least one outlet terminal prior to starting the heat treatment process,
performing the heat treatment process in an evacuated state, and
supplying the firing chamber with ambient air at a predetermined temperature via an inlet terminal.

17. The method according to claim 16 , comprising
starting from a predetermined temperature during cool down or at any other point of time during the heat treatment process, continuously aspirating ambient air through the firing chamber by intervention of the vacuum source.

Assignees

• Ivoclar Vivadent Ag

Inventors

• Jussel Rudolf
• Schlegel Manuel

Classifications

• F27B17/025 Primary

  for dental workpieces · CPC title

• A61C13/20 Primary

  Methods or devices for soldering, casting, moulding or melting {(A61C13/04, A61C13/081 take precedence)} · CPC title

• F27D2021/0007

  Monitoring the pressure · CPC title