The invention relates to a sintering furnace (1) for components (15) made of a sintered material, in particular for dental components, comprising a furnace chamber (2) having a chamber volume (VK), wherein a heating device (5), a receiving space (9) having a gross volume (VB) located in the chamber volume (VK) and delimited by the heating device (5), and a useful region (10) having a useful volume (VN) located in the gross volume (VB), are disposed in the furnace chamber (2). The furnace chamber (2) has an outer wall (3) consisting of a plurality of walls having a wall portion (7) to be opened for introduction of a component to be sintered having an object volume (VO) into the receiving space (9). In the furnace chamber (2) the heating device (5) has a thermal radiator (6) having a radiation field (13) which is disposed on at least one side of the receiving space (9). At least the useful volume (NV) disposed in the receiving space (9) is disposed in the radiation field (13) of the radiator (6), wherein the maximum possible distance (d) of the component (15) to be sintered from the radiator (6) corresponds to at most twice the dimension (D.sub.y) of the maximum useful volume (VN).

A sintering furnace (1) for sintering dental workpieces (2), wherein the sintering furnace (1) has a heating element (3) with a receiving space (4) for receiving the workpiece (2) during sintering. The receiving space (4) is a portion of an interior space (5) within the heating element (3), and the heating element (3) comprises or consists of silicon carbide, wherein the heating element (3) is designed, at least in parts, as a slotted tube, and the slot (6) in the tube forming the heating element (3) has a helical configuration in a heating region (7), in which the heating element (3) encloses the receiving space (4).

The invention relates to a dental furnace, in particular a high-temperature dental furnace for oxide ceramics such as zirconium dioxide having sintering temperatures of between 1300 and 1850° C., comprising a heating element (10) which is intended to give off heating energy to the firing chamber. It is provided that the heating element (10) comprises at least two heating element sections (48, 50) adjoining one another at a transition area (34) which is not current-carrying and/or which extends away laterally, that the transition area (34) is supported on a position, in particular on the free end, spaced apart from the electrical connections (16, 18) on the dental furnace and carries at least the two adjoining parts of heating element sections (48, 50).

The invention relates to a dental furnace, in particular a high-temperature dental furnace for oxide ceramics such as zirconium dioxide with sintering temperatures of between 1350° C. and 1650° C., having heating elements (14, 16) which are intended to give off heating energy to a firing chamber (12) in the dental furnace (10). The heating elements (14, 16) are configured as electrical resistance heating elements and supported below the firing chamber (12) each by means of at least one heating element support foot (18). The heating elements (14, 16) extend vertically to the top starting from the heating element support feet (18) and at the top, end in an arch (46), in particular in a semicircular arch or possibly in a pointed arch, without an upper lateral support, in particular not in the region of the arch (46).

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.

A sintering furnace for components made of a sintered material, in particular for dental components, having a furnace chamber having a chamber volume (VK). A heating device, a receiving space having a gross volume (VB) located in the chamber volume (VK) and delimited by the heating device, and a useful region having a useful volume (VN) located in the gross volume (VB), are disposed in the furnace chamber. The furnace chamber has an outer wall consisting of walls having a wall portion to be opened for introduction of a component to be sintered having an object volume (VO) into the receiving space. In the furnace chamber the heating device has a thermal radiator having a radiation field which is disposed on at least one side of the receiving space. At least the useful volume (NV) disposed in the receiving space is disposed in the radiation field of the radiator.

A sintering furnace for components made of a sintered material, in particular for dental components, having a furnace chamber having a chamber volume (VK). A heating device, a receiving space having a gross volume (VB) located in the chamber volume (VK) and delimited by the heating device, and a useful region having a useful volume (VN) located in the gross volume (VB), are disposed in the furnace chamber. The furnace chamber has an outer wall consisting of walls having a wall portion to be opened for introduction of a component to be sintered having an object volume (VO) into the receiving space. In the furnace chamber the heating device has a thermal radiator having a radiation field which is disposed on at least one side of the receiving space. At least the useful volume (NV) disposed in the receiving space is disposed in the radiation field of the radiator.

The invention relates to an arrangement of a furnace and of bulk material of glass particles, said furnace (10) comprising a pressing punch (36), a pressure, distance and/or speed sensor and a control device for controlling a pressing process based on the output signal of the sensor. The sensor detects at least a pressure, position and/or motion parameter of the pressing punch (36). The pressing punch (36) acts on the bulk material of glass particles (32)—possibly via an interposed ram (28)—, said glass particles being guided and crystallizable in a press channel (30). The trigger criterion for the process control is a change of at least a motion parameter of the pressing punch (36) upon softening of the bulk material of glass particles (32) which change is detected by the sensor.

A microwave furnace has a furnace chamber formed between a chamber housing and a sintering platform for an object to be sintered. A microwave source is arranged for emitting microwaves into the furnace chamber. The microwave furnace further has a susceptor that comprises a material which over a temperature range of the material of at least 23 C to 700 C couples into microwaves. The susceptor and the furnace chamber are movable relative to each other between a first position, in which the susceptor is positioned relative to the furnace chamber, and a second position in which the susceptor is positioned further retracted from the furnace chamber relative to the first position. The invention helps providing a zirconia material with a relative homogeneous material structure.

The application basically comprises supplying a high-temperature ultra-high vacuum furnace, the sole chamber of which is metal, in which an electrically conductive crucible, preferably made of tantalum, is placed onto an insulating support, preferably a ceramic, and is induction heated by a winding wound around the crucible. The insulating tube, preferably made of quartz, that is arranged between the induction winding and the crucible, advantageously acts as a surface on which the condensable species can condense. The quartz insulating tube especially allows the induction winding to be protected.