Abstract
The invention relates to a furnace having a vertical orientation for dental components, comprising a combustion chamber, which is open at the bottom and the opening of which can be closed by means of a furnace door, which is lowered in the vertical direction in the open position, and comprising a depositing region for the heated component, which depositing region is arranged at a distance from the opening in the combustion chamber. The depositing region is part of the furnace, and a cooling device that acts on the depositing region is arranged on or in the furnace. A heat-resistant base has a heat-resistant support arranged in a housing, which support has an active or passive cooling device, which, for example, has a Peltier element.
Claims
1. Furnace having a vertical orientation for heating at least one dental component, comprising a combustion chamber, which is open at the bottom, and the opening of which can be closed by means of a furnace door, which is lowered in the vertical direction in the open position, and comprising a depositing region for a heated component, which depositing region is arranged at a distance from the opening in the combustion chamber, wherein the depositing region is part of the furnace, and a cooling device that acts on the depositing region is arranged on or in the furnace, wherein the depositing region comprises a heat-resistant support for the heated component and that the cooling device acts on the support, and wherein the support (i) comprises ventilation openings, by means of which a cooling air flow is guided onto the heated component to be arranged in the depositing region on the support or (ii) is cooled with the aid of a Peltier element, which is thermally coupled directly to the support.
2. Furnace according to claim 1, wherein when the support region comprises ventilation openings, the ventilation openings are fluidically connected to a fan to provide a cooling air flow.
3. Furnace according to claim 2, wherein when the support region comprises ventilation openings an air-permeable, heat-insulating insert part is arranged between the fan and the support.
4. Furnace according to claim 1, wherein the depositing region is arranged outside a thermal radiation field of the open combustion chamber.
5. Furnace according to claim 1, wherein the furnace comprises two furnace doors, of which one furnace door is brought into a cooling position after the opening of the combustion chamber has been cleared, while the other furnace door closes the combustion chamber in the closed position.
6. Furnace according to claim 1, further comprising a device for automatically repositioning the heated component from the open combustion chamber into the depositing region.
7. Furnace according to claim 6, wherein the device for automatically repositioning the heated component comprises a gripper arm or a robot arm.
8. Furnace according to claim 6, wherein the device for automatically repositioning the heated component comprises a tappet, a chute and a collecting basket.
9. Furnace according to claim 1, wherein the depositing region or the support comprises means for temperature measurement in the depositing region or the support or the component to be cooled.
10. Furnace according to claim 9, wherein comparison means and display means are provided, to compare the temperature of the component to be cooled to a predetermined limit temperature and to display said temperature when the limit temperature is reached.
11. Furnace according to claim 9, wherein, with the aid of a control unit, the cooling device provides a cooling output which is dependent on the signal of the means for temperature measurement.
12. Furnace according to claim 1, wherein a plurality of supports having a plurality of cooling devices are provided in a housing.
13. Furnace according to claim 12, wherein the cooling output of each support is individually controllable.
14. Furnace according to claim 1, wherein the cooling device is arranged at a distance from the depositing region in a housing section, past which the component is moved when the component is brought out of the combustion chamber.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Design examples of the invention are shown in the drawing. The drawing shows:
(2) FIG. 1 a lower part of a dental furnace with an open combustion chamber and a depositing region arranged in front of it;
(3) FIG. 1A the depositing region of FIG. 1 in detail with the component placed upon it;
(4) FIG. 2 a dental furnace with an open combustion chamber and a depositing region arranged on the combustion chamber;
(5) FIG. 3 a heat-resistant base, which is formed independently of a dental furnace;
(6) FIG. 4 a dental furnace with an open combustion chamber and a depositing region arranged below the open furnace door;
(7) FIG. 5 a dental furnace with an open combustion chamber and a depositing region with free convection arranged in front of the combustion chamber;
(8) FIG. 6 a dental furnace with an open combustion chamber and a depositing region with a Peltier element arranged in front of the combustion chamber;
(9) FIG. 7 the dental furnace of FIG. 1 with automatic repositioning of the hot component by means of a gripper arm or robot arm;
(10) FIG. 8 the dental furnace of FIG. 1 with automatic repositioning of the hot component by means of a tappet (e.g. linear actuator or compressed air pipe), a chute and a collecting basket;
(11) FIG. 9 a dental furnace with an open combustion chamber and a depositing region arranged on the furnace door of the open combustion chamber, with a ventilation system mounted in the housing of the furnace;
(12) FIG. 10 the dental furnace of FIG. 9 with two furnace doors, one of which is moved into a special cooling position, while the other closes the combustion chamber;
(13) FIG. 11 a plurality of supports having a plurality of cooling devices arranged in a housing;
(14) FIG. 12 a base with a control unit.
DETAILED DESCRIPTION OF THE INVENTION
(15) FIG. 1 shows a lower part of a vertically oriented dental furnace 1 with a combustion chamber 2, which is open at the bottom, and the opening 2.1 of which can be closed by means of a furnace door 3, which is lowered in the vertical direction in the open position. The lowered furnace door 3, which is in a loading position, comprises a plate-shaped wall section 4, on which a lower and an upper door stone 5, 6 are provided to insulate the combustion chamber. On its upper side, the upper door stone 6 comprises a support surface 7 for a component for heat treatment in the combustion chamber 2. To charge the furnace, the component is placed on the support surface 7 of the furnace door, which is in the loading position, and the furnace door is moved vertically upward and closes the combustion chamber in the closed position. After the conclusion of the heat treatment in the closed combustion chamber 2, the furnace door is opened by lowering and, after reaching the loading position, the component, which still has residual heat, is removed from the support surface 7 and brought into a depositing region 10, which is arranged at a distance from the opening 2.1 of the combustion chamber 2 as part of the furnace 1, in this case in front of the opening 2.1 of the combustion chamber 2. It is equally conceivable, however, to arrange the depositing region 10 laterally adjacent to the opening 2.1 of the combustion chamber.
(16) The component 11, which is to be subjected or has been subjected to the heat treatment in the combustion chamber 2, can be set down on said depositing region 10.
(17) As can be seen from FIG. 1A, the depositing region 10 comprises a heat-resistant support 12, on which the heated component 11 can be deposited. The depositing region 10 is formed as part of a housing 13 of the dental furnace 1, more precisely as part of a base plate.
(18) Provided in the depositing region 10 is a cooling device 14, which acts on the support 12 and comprises a fan 15 mounted to the housing 13. Via ventilation slits 16 in the support 12, said fan directs an air flow 17 onto the component 11, which has been removed from the combustion chamber and placed on the support. In the case of a furnace mounted on a base, there is a gap between the depositing region 10 and the base. Cooling air can pass through this gap to the underside of the support or can also be pulled in by the fan and cool the support.
(19) An air-permeable, heat-insulating insert part 18 is arranged between the fan 15 and the support 12 to prevent the thermal radiation of the component 11 from affecting the fan 15.
(20) FIG. 2 shows a dental furnace 1 with an open furnace door 3 of the combustion chamber 2 and a depositing region 10, which is arranged on the combustion chamber 2 at a distance from the opening 2.1 of the combustion chamber 2 and has a support 12 provided with ventilation slits 16, via which an air flow 17 is directed onto the component 11.
(21) FIG. 3 shows a heat-resistant base 21 for a heated dental component 11, which is formed independently of a dental furnace and has a heat-resistant support, which is arranged in a housing 22 and comprises an active or passive cooling device. In this case, ventilation slits 16, via which an air flow can reach the component 11, are provided in the support as passive cooling device. The air flow 17 can be amplified by a not depicted fan in the housing 22, which creates an active cooling device.
(22) FIG. 4 shows a dental furnace with an open combustion chamber 2 and a depositing region 10, which is arranged below the open furnace door 3 at a distance from the opening 2.1 of the combustion chamber 2, pictured here in partial section. The support 12, on which the component 11 is located, is arranged in the depositing region 10. As already depicted in FIG. 1, ventilation slits 16, through which an air flow 17 can escape onto the component 11, are provided in the support 12. The structure can be the same as that of the base from FIG. 3.
(23) FIG. 5 shows a dental furnace 1 with an open combustion chamber 2 and a depositing region 10 with free convection arranged in front of the combustion chamber 2 at a distance from the opening 2.1 of the combustion chamber 2. Ventilation slits 16 are again provided in the support 10 for this purpose; there is, however, no need for the presence of a fan. An air flow is produced by natural convection of the still warm component 11.
(24) FIG. 6 shows a dental furnace with an open combustion chamber 2 and a depositing region 10, which is arranged in front of the combustion chamber 2 at a distance from the opening 2.1 of the combustion chamber 2 and has a Peltier element 30 instead of a passive or active air flow as in the preceding FIGS. 1 to 5.
(25) The Peltier element 30 is thermally coupled to the support 12 in such a way that its cool side interacts with and cools the support 12, and its warm side is directed downward and is cooled by the ambient air below the housing.
(26) The base from FIG. 3 can likewise comprise a Peltier element as an active cooling device instead of a fan.
(27) As in the other embodiments, in the case of a furnace mounted on a base, there is a gap between the depositing region and the base. Cooling air can pass through this gap to the underside of the support or can also be pulled in by the fan and cool said support.
(28) FIG. 7 shows the dental furnace from FIG. 1 with automatic repositioning of the hot component 11′, 11 disposed on the open furnace door 3 with the aid of a gripper arm 41′, 41 or a robot arm from the upper door stone 7 into the depositing region 10, and with additional temperature measurement via a sensor 42 for measuring the temperature in the depositing region 10.
(29) FIG. 8 shows the dental furnace from FIG. 1 with automatic repositioning of the hot component 11′, 11 disposed on the open furnace door 3 with the aid of a tappet 51, which can, for example, be designed as a linear actuator or as a compressed air pipe, a chute 52 and a collecting basket 53 from the upper door stone 7 into the depositing region 10, likewise with additional temperature measurement in the depositing region via a sensor 42. A thermal imaging camera 54 is provided as well, which is directed toward the component disposed on the support 12 and captures a thermal image.
(30) FIG. 9 shows a dental furnace 1 with an open combustion chamber 2 and a support surface 7 for the component 11 arranged on the upper door stone 6 of the furnace door 3, which is in a loading position. A cooling device is mounted in the housing 13, at a distance from the support surface 7. In this case, the support surface 7 fulfills the function of a depositing region, because the component remains on the support surface 7 during cooling. Cooling occurs with the aid of an air flow 17, which is produced by a fan 15 and escapes from the housing 13 via ventilation slits 16 in the housing 13 directed onto the component 11. To change the location from which the air flow 17 directed onto the component 11 leaves the housing 13, the fan 15 can optionally be adjustable relative to the housing. In this case, the loading position of the furnace door is also the same as the cooling position and repositioning is not necessary, because the sinter support and the cooling support are one and the same. In order to improve cooling, provision can be made to change the cooling position relative to the loading position instead of changing the position of the fan.
(31) During the cooling of the component 11, the temperature is measured via a sensor 42 for temperature measurement in the upper door stone 6; thermal image acquisition with a thermal imaging camera 54 mounted in the housing 13 can optionally be provided as well.
(32) The cooling device acting on the depositing region is arranged in a housing section, past which the component 11 is moved when it is brought out of the combustion chamber 2. The cooling device is mounted in an already existing housing section. The thermal imaging camera can additionally also be arranged in this housing section, to record the cooling of the component or to evaluate said cooling for the purpose of controlling the cooling device.
(33) FIG. 10 shows the dental furnace from FIG. 9 with two furnace doors 3, 3′, one of which, namely furnace door 3, is moved into a cooling position corresponding to that of FIG. 9 after the opening 2.1 of the combustion chamber 2 has been cleared, while the other furnace door 3′ closes the combustion chamber 2 in the closed position. In the case of a depicted vertical furnace, the closed position is the upper position, the cooling position is the lower position, and the cooling device is arranged in the housing between these two positions.
(34) The alternating adjustment of the two furnace doors 3, 3′ is effected via one respective adjusting mechanism 61, 62 for each one of the two furnace doors 3, 3′. For at least one adjusting mechanism 62, a pivoting movement for the furnace door 3 can furthermore be provided to prevent a collision between the two furnace doors 3, 3′ during lowering out of the combustion chamber 2 and raising up into the combustion chamber.
(35) With the exception of the embodiment of FIG. 9, the depositing region is always arranged outside the direct thermal radiation field of the open combustion chamber 2. As is the case here in a vertical furnace, this can, for example, be below the furnace door or on the furnace itself or even laterally adjacent to it.
(36) FIG. 11 shows a plurality of supports 71-74, 75, 76 of different sizes arranged in a housing 70, each of which interacts with one respective, not depicted, cooling device. Such a plurality of supports can be provided in both the furnace and the base. In the case in which measurement of the temperature via a sensor is provided individually for each support, the cooling device can provide a cooling output, which is dependent on the signal from the temperature sensor, by means of a control unit. The cooling output of the plurality of cooling devices can therefore be operated individually and in a temperature-dependent manner with the aid of a not depicted controller.
(37) FIG. 12 shows a base 80 with a temperature sensor 42 in the support 12 and with comparison means 81, to compare the temperature of the component 11 to be cooled and arranged on the support, which is measured by the temperature sensor 42, to a predetermined limit temperature. The reaching of the limit temperature is displayed via display means 82.
(38) The comparison means 81 can be part of a control unit 83 for the cooling device, which provides a cooling output that is dependent on the signal of the means for temperature measurement 42, for example by controlling the speed of the fan 15.
