DENTAL FURNACE AND METHOD FOR OPERATING A DENTAL FURNACE

Abstract

A dental furnace for firing dental-ceramic compounds, comprising a combustion chamber for receiving ceramic elements to be fired. The heating of the combustion chamber is carried out using a heating device. The heating device is connected to an evaluation device via a resistance measuring device. The temperature in the combustion chamber and/or an operating state of the dental furnace can be determined using the evaluation device.

Claims

1. A dental furnace for firing dental ceramic compounds, comprising a combustion chamber for receiving ceramic elements to be fired, an electric heating device for heating/firing the ceramic element, a resistance measurement device connected to the heating device, wherein the resistance measurement device is connected to the heating device at least at the two electrical connection points of the heating device, and an evaluation device for determining a temperature in the firing chamber and/or an operating state of the dental furnace, said evaluation device being connected to the resistance measurement device.

2. The dental furnace for firing dental ceramic compounds according to claim 1, wherein the heating device comprises a heating wire.

3. The dental furnace for firing dental ceramic compounds according to claim 2, wherein the connection points are arranged at the two ends of the heating wire, wherein preferably one of the connection points is arranged at the beginning and the second connection point is arranged at the end of the heating wire, wherein it is particularly preferred that one of the connection points is provided in the cover area of the firing chamber.

4. The dental furnace for firing dental ceramic compounds according to claim 1, wherein the heating device comprises one or a plurality of radiant heaters in particular connected in series.

5. The dental furnace for firing dental ceramic compounds according to claim 3, wherein at least one further connection point is provided in a central portion of the heating device.

6. The dental furnace for firing dental ceramic compounds according to claim 5, wherein the at least one further connection point is provided between the two electrical connection points of the heating device, in particular between the connection point at the beginning and the connection point at the end of the heating wire.

7. The dental furnace for firing dental ceramic compounds according to claim 1, wherein the evaluation device determines a resistance change and/or that a temperature measurement device is provided in particular in the area of the ceramic element to be fired.

8. The dental furnace for firing dental ceramic compounds according to claim 7, wherein the evaluation device is connected to the temperature measurement device and establishes a relationship between the measured resistance and the measured temperature.

9. The dental furnace for firing dental ceramic compounds according to claim 1, wherein the evaluation device is connected to a data storage element in which in particular measurement data can be stored, wherein the evaluation device compares measurement data in order to determine the wear of the heating device.

10. A method for operating a dental furnace according to claim 1, comprising the following steps: measuring a resistance of the heating device using the resistance measurement device, transmitting the measured resistance to the evaluation device and determining a temperature and/or an operating state by the evaluation device, wherein the evaluation device is calibrated by establishing a relationship between a measured resistance and a measured temperature.

11. The method for operating a dental furnace according to claim 10, wherein a resistance change is measured and a temperature change is determined therefrom.

12. The method for operating a dental furnace according to claim 10, wherein the measured resistance data are stored in the data storage elements in particular together with measuring times, wherein a wear of the heating element is determined in particular based on the stored data.

13. The method for operating a dental furnace according to claim 10, wherein the resistance measurement is performed with the firing chamber open.

14. The method for operating a dental furnace according to claim 10, wherein the resistance measurement and the characteristics calibration is performed with the firing chamber closed.

15. The method for operating a dental furnace according to claim 10, wherein subsequent process steps, e.g. the sequential opening and closing of the firing chamber, are controlled in dependence on the temperature determined.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0020] The FIGURE shows a highly simplified schematic sectional view of the dental furnace according to the dental furnace.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0021] The dental furnace has a base element 10 on which a base 12 is arranged. The base 12 serves for arranging a schematically illustrated ceramic element 14 thereon. In the FIGURE, a housing 16 is arranged in the open position and can be displaced in the direction of an arrow 18 for closing, so that a firing chamber 20 is formed.

[0022] A heating device 24 arranged helically as a heating wire is schematically illustrated in the side wall 22 which is in particular cylindrical in shape.

[0023] For determining the resistance of the heating wire 24, an evaluation device 26 is connected to the heating wire at two connection points 28, 30. The connection points 28, 30 are arranged at the two ends of the heating wire or the heating elements 24, so that, for example, the connection point 28 is arranged at the beginning and the connection point 30 is arranged at the end of the part of the heating wire 24 that is relevant for heating the firing chamber 20.

[0024] A resistance measurement device 25 is connected to the connection points 28, 30. The resistance data determined by the resistance measurement device 25 are transmitted to the evaluation device 26. The resistance measurement device 25 can also be integrated in the evaluation device 26.

[0025] Furthermore, a further connection point 38 can be provided in particular in a central portion of the heating wire 24. The latter is in turn connected to the resistance measurement device 25.

[0026] By means of the evaluation device 26, a resistance of the heating wire 24 or a change in resistance can be determined. For calibration and thus for determining a defined temperature, a temperature sensor 32 is arranged within the base 12, which is also connected to the evaluation device 26.

[0027] The data determined in the evaluation device 26 are transmitted to a data storage element 34. By a corresponding evaluation of the data, it is possible, for example, to determine the wear of the heating wire. Further, the data determined by the evaluation device can be transmitted to a control device 36. The control device 36 may, for example, control an opening or closing of the housing 16.