Dental furnace

Abstract

The invention relates to a dental furnace (10) for dental restorations comprising a firing chamber into which, in particular between a furnace bottom part (14) and a furnace upper part (12), the dental restoration, in particular within a muffle, can be introduced, and a sensor that is connected with a control device (52) for the dental furnace (10), characterized in that the sensor, in particular the temperature sensor (22), is arranged outside the firing chamber and comprises a detection range (40) that also extends outside the firing chamber.

Claims

1. A dental furnace for dental restorations comprising a furnace bottom part, a furnace upper part, a firing chamber into which the dental restorations can be introduced, a sensor that is remotely or locally connected to a control device for the dental furnace, the sensor detecting and recognizing an approaching object and a user of the dental furnace, wherein the sensor is arranged outside the firing chamber and comprises a detection range that also extends outside the firing chamber, wherein the said sensor is formed as a proximity and/or a temperature sensor, and wherein the sensor is configured to respond to an elevated temperature compared to room temperature.

2. The dental furnace according to claim 1, wherein the dental furnace is formed as a muffle press furnace for dental restoration parts, wherein the firing chamber is adapted for the accommodation of a muffle and wherein an object that is to be detected in the detection range comprises the muffle of the muffle press furnace.

3. The dental furnace according to claim 1, wherein the control device performs a special control function if the muffle or the dental restoration reaches the detection range of the sensor.

4. The dental furnace according to claim 3, wherein the control function includes a function that is associated with a start of a firing process of the dental furnace.

5. The dental furnace according to claim 4, wherein the start of the firing process comprises switching on of the dental furnace.

6. The dental furnace according to claim 5, wherein the switching on of the dental furnace comprises opening of the dental furnace.

7. The dental furnace according to claim 1, wherein the detection range of the temperature sensor enlarges in a direction transverse to the temperature sensor if starting from the temperature sensor, and that the detection range extends obliquely to a lateral surface of the dental furnace.

8. The dental furnace according to claim 1, wherein the detection range of the temperature sensor extends along the furnace upper part.

9. The dental furnace according to claim 1, wherein the detection range of the temperature sensor substantially extends horizontally or obliquely upwards or obliquely downwards and covers an area to the side of the furnace upper part.

10. The dental furnace according to claim 1, wherein the temperature sensor is attached to the furnace bottom part and wherein the detection range of the sensor extends upwards about the optical axis of the sensor.

11. The dental furnace according claim 1, wherein the detection range of the temperature sensor, starting from the furnace bottom part, extends upwards or obliquely upwards along the furnace upper part.

12. The dental furnace according to claim 1, wherein the temperature sensor has an optical axis facing towards the furnace and wherein the optical axis of the temperature sensor hits a reflector that is formed in a manner for reflecting the heat radiation that impinges on the temperature sensor.

13. The dental furnace according to claim 1, wherein the optical axis of the temperature sensor intersects the vertical axis of the firing chamber in the furnace upper part or extends at an angle that deviates at most 15° C. from a straight line that connects the vertical axis with the temperature sensor.

14. The dental furnace according to claim 1, wherein the temperature sensor comprises a spectral sensitivity with a focus in the infrared wavelength range, and responds to objects that are located within the detection range and have an elevated temperature.

15. The dental furnace according to claim 14, wherein the elevated temperature is a higher temperature than room temperature.

16. The dental furnace according to claim 15, wherein the elevated temperature is more than 100 C.

17. The dental furnace according to claim 14, wherein the elevated temperature is more than 300 C.

18. The dental furnace according to claim 1, wherein the temperature sensor is a thermal imaging camera that detects image information of objects located within the detection range as far as they exhibit an elevated temperature.

19. The dental furnace according to claim 1, wherein the control device opens the dental furnace when the temperature sensor detects the presence of an object having an elevated temperature in the detection range.

20. The dental furnace according to claim 1, wherein the temperature sensor comprises a detection range which is subdivided into two subdetection ranges, and wherein the control device opens the dental furnace when the temperature sensor first detects an object in the first subdetection range that is more distant from the furnace, and subsequently detects the object in a detection range that is closer to the furnace.

21. The dental furnace according to claim 1, wherein the temperature sensor detects a certain approach of an object to the furnace.

22. The dental furnace according claim 1, wherein the temperature sensor is embodied as a one- or two-dimensional field of infrared-sensitive diodes and wherein the temperature sensor is arranged at least ten centimeters away from the firing chamber.

23. The dental furnace according to claim 1, wherein said sensor is arranged and adapted to detect firing carriers for dental restoration parts.

24. The dental furnace according to claim 1, wherein said sensor is arranged and adapted to detect auxiliary filing parts such as susceptors.

25. The dental furnace according to claim 1, wherein said sensor is arranged remote from the dental furnace and is connected by a remote connection like WIFI, LAN or Bluetooth, and wherein said sensor is arranged to detect an object which is remote from that dental furnace.

26. The dental furnace according to claim 1, wherein said sensor is arranged to detect the direction of motion and that control device provides a control function dependent on the direction of motion.

27. The dental furnace according to claim 1, wherein said sensor is arranged to detect the status of a debinding oven which is located close to or remote from said dental furnace, wherein said control device is adapted to control the status of the dental furnace based on an output signal received from said sensor, and wherein said dental furnace preferably is a sintering furnace.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages, details and features emerge from the following description of an exemplary embodiment in conjunction with the drawings, in which:

(2) FIG. 1 illustrates a schematic view of an inventive dental furnace in one exemplary embodiment;

(3) FIG. 2 illustrates a side view of a further embodiment of a dental furnace according to the invention; and

(4) FIG. 3 illustrates a schematic view of an inventive dental furnace in one exemplary embodiment.

DETAILED DESCRIPTION

(5) The dental furnace 10 illustrated in FIG. 1 comprises a furnace hood 12 as a furnace upper part, as well as a furnace bottom part 14. It is configured as a muffle press furnace, and the circular furnace hood 12 forms inside in a firing chamber, whose diameter is also sufficient for accommodating the likewise circular and substantially cylindrical muffle.

(6) The furnace bottom part comprises an inclined plane 16 which supports a touch-sensitive display 18 via which the inventive dental furnace 10 can be actuated.

(7) The furnace hood 12 is supported in a manner known per se on the furnace lower part 14 via a lifting/pivoting device so that it may be lifted off the furnace lower part and swung open by leaving a gap. In also a manner known per se, the furnace can perform a firing operation by switching on the heating in the furnace hood with the furnace hood being closed and by inserting a press stamp or plunger into the muffle with the muffle being heated, said press stamp or plunger pressing the dental restoration material in the muffle into prepared mold cavities.

(8) According to an embodiment of the invention it is provided that a temperature sensor 22 is supportedly attached to the furnace bottom part which sensor is directed towards the vertical axis 24 of the dental furnace. The support of the temperature sensor 22 is immediately effected on the upper side 26 of the furnace bottom part 14, i.e., at the lower end of the furnace hood 12.

(9) Further, a reflector 30 is attached to the outer periphery of the furnace hood 14 next to the temperature sensor 22.

(10) The reflector 30 is formed as a sheet metal strip, for example from aluminum foil, or as some other metal plate and is suitable for reflecting the heat radiation. It extends away from the furnace hood at a slight angle, for example at an angle of 45°. It is to be understood that the exact orientation can be adapted to the requirements within wide ranges.

(11) In case of a tilt angle of 45° of the reflector, a detection range 40 extends at an angle of 90° relative to the optical axis 42 of the temperature sensor 22. It is to be understood that the detection range 40 conically widens or expands in a manner known per se. Preferably a quite strong bunching is provided that enables a particularly sensitive detection of the temperature also in case of a larger distance. The bunching can also be improved by forming the reflector 30 according to the type of a concave mirror.

(12) In the illustrated exemplary embodiment a muffle 50 is schematically illustrated at a position in which the heat radiation emitted by it lies within the detection range 40 of the temperature sensor 22.

(13) The muffle has previously been heated in a pre-heating furnace to a temperature of 700° C. and still has a temperature of approximately 500° C. at its outside. The heat radiation emitted by the muffle now impinges on the temperature sensor 22 in the detection range 40 via the reflector 30. The temperature sensor 22 is electrically connected to a control device 52 that is preferably received within the furnace bottom part 14. In case of the approach of the hot muffle 50, the control device triggers an opening signal for the lifting/pivoting device 20 which, activated by the signal, lifts the furnace hood 12 and enables the muffle 50 to be placed on the furnace bottom part below the optical axis 42, and the movement of the muffle 50 towards the dental furnace does not have to be decelerated.

(14) It is to be understood that the connection between the temperature sensor 22 and the control device 52 can be formed in any suitable manner. The temperature sensor 22 is in fact fixedly installed on a base, preferably is attached to the dental furnace, but is electrically connected to the control device in any suitable manner, such as, for example by radio, by Bluetooth or via an infrared connection, or via an electric line in a manner known per se.

(15) It is to be understood that the orientation of the detection range can be effected in any suitable manner. If necessary, also several reflectors 30 can for example be attached to the furnace hood 12 as standard. Moreover, the temperature sensor 22 may be positioned at several possible attachment positions. The dental technician, even also as a left-hander for example, can then install the temperature sensor 22 in any suitable manner and can automatically start the opening upon an approach of the muffle 50 to the dental furnace 10.

(16) FIG. 2 shows a modified embodiment of a dental furnace. The same reference numerals indicate the same or corresponding components.

(17) In contrast to the embodiment according to FIG. 1, the detection range 40 of the temperature sensor 22 is substantially aligned vertically. The optical axis 42 of the temperature sensor 22 extends, starting from the furnace lower part 14, vertically upwards, for example at an oblique angle laterally in front of the furnace hood 12.

(18) It is to be understood that also in this case several attachment possibilities for the temperature sensor 22 can be provided if necessary that enable the modification of the detection range at the option of the dental technician. In this case, too, the triggering of the temperature sensor 22 is effected by the fact that the muffle 50 at least partially enters the detection range 40 and that the heat radiation emitted by the muffle 50 lifts the furnace hood 12 via the control device 52 in the furnace bottom part.

(19) In a further embodiment, the sensor is located remote from the dental furnace but connected to its control device via a suitable remote connection path, such as e.g. WIFI, LAN or Bluetooth. The status of a remote object is sensed by the sensor, and the dental furnace is controlled based on the sensed status of this object.

(20) Such an object may be a preheating oven. If it opens as the dental restoration parts are sufficiently preheated, the opening process is detected by the sensor.

(21) Then the dental furnace is automatically opened with a preselected delay. Thus the user when arriving at the dental furnace with the hot (i.e., about 700° C. hot) dental restoration parts will not have to wait until the dental furnace is ready to receive these parts.

(22) By this, an undue handling delay of e.g., 10 seconds may be avoided.

(23) Another example is to use the status of a debinding oven 60, shown in FIG. 3, for controlling the status of the dental furnace. Such oven may be arranged close to the dental furnace, or remote from it, and the control device may select a suitable timing to optimize the handling processes in dental laboratories.

(24) Although preferred embodiments have been depicted and described in detail herein, it will be apparent to those skilled in the relevant art that various modifications, additions, substitutions, and the like can be made without departing from the spirit of the invention and these are therefore considered to be within the scope of the invention as defined in the claims which follow.